linux/drivers/hid/hid-core.c

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// SPDX-License-Identifier: GPL-2.0-or-later
/*
* HID support for Linux
*
* Copyright (c) 1999 Andreas Gal
* Copyright (c) 2000-2005 Vojtech Pavlik <vojtech@suse.cz>
* Copyright (c) 2005 Michael Haboustak <mike-@cinci.rr.com> for Concept2, Inc
* Copyright (c) 2006-2012 Jiri Kosina
*/
/*
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/list.h>
#include <linux/mm.h>
#include <linux/spinlock.h>
#include <asm/unaligned.h>
#include <asm/byteorder.h>
#include <linux/input.h>
#include <linux/wait.h>
#include <linux/vmalloc.h>
#include <linux/sched.h>
HID: Fix race condition between driver core and ll-driver HID low level drivers register new devices with the HID core which then adds the devices to the HID bus. The HID bus normally immediately probes an appropriate driver which then handles HID input for this device. The ll driver now uses the hid_input_report() function to report input events for a specific device. However, if the HID bus unloads the driver at the same time (for instance via a call to /sys/bus/hid/devices/<dev>/unbind) then the hdev->driver pointer may be used by hid_input_report() and hid_device_remove() at the same time which may cause hdev->driver to point to invalid memory. This fix adds a semaphore to every hid device which protects hdev->driver from asynchronous access. This semaphore is locked during driver *_probe and *_remove and also inside hid_input_report(). The *_probe and *_remove functions may sleep so the semaphore is good here, however, hid_input_report() is in atomic context and hence only uses down_trylock(). If it cannot acquire the lock it simply drops the input package. The low-level drivers report input events synchronously so hid_input_report() should never be entered twice at the same time on the same device. Hence, the lock should always be available. But if the driver is currently probed/removed then the lock is not available and dropping the package should be safe because this is what would have happened if the package arrived some milliseconds earlier/later. This also fixes another race condition while probing drivers: First the *_probe function of the driver is called and only if that succeeds, the related input device of hidinput is registered. If the low level driver reports input events after the *_probe function returned but before the input device is registered, then a NULL pointer dereference will occur. (Equivalently on driver remove function). This is not possible anymore, since the semaphore lock drops all incoming packages until the driver/device is fully initialized. Signed-off-by: David Herrmann <dh.herrmann@googlemail.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2011-08-10 12:02:07 +00:00
#include <linux/semaphore.h>
#include <linux/hid.h>
#include <linux/hiddev.h>
#include <linux/hid-debug.h>
#include <linux/hidraw.h>
#include "hid-ids.h"
/*
* Version Information
*/
#define DRIVER_DESC "HID core driver"
int hid_debug = 0;
module_param_named(debug, hid_debug, int, 0600);
MODULE_PARM_DESC(debug, "toggle HID debugging messages");
EXPORT_SYMBOL_GPL(hid_debug);
static int hid_ignore_special_drivers = 0;
module_param_named(ignore_special_drivers, hid_ignore_special_drivers, int, 0600);
MODULE_PARM_DESC(ignore_special_drivers, "Ignore any special drivers and handle all devices by generic driver");
/*
* Register a new report for a device.
*/
struct hid_report *hid_register_report(struct hid_device *device,
unsigned int type, unsigned int id,
unsigned int application)
{
struct hid_report_enum *report_enum = device->report_enum + type;
struct hid_report *report;
if (id >= HID_MAX_IDS)
return NULL;
if (report_enum->report_id_hash[id])
return report_enum->report_id_hash[id];
report = kzalloc(sizeof(struct hid_report), GFP_KERNEL);
if (!report)
return NULL;
if (id != 0)
report_enum->numbered = 1;
report->id = id;
report->type = type;
report->size = 0;
report->device = device;
report->application = application;
report_enum->report_id_hash[id] = report;
list_add_tail(&report->list, &report_enum->report_list);
return report;
}
EXPORT_SYMBOL_GPL(hid_register_report);
/*
* Register a new field for this report.
*/
static struct hid_field *hid_register_field(struct hid_report *report, unsigned usages)
{
struct hid_field *field;
if (report->maxfield == HID_MAX_FIELDS) {
hid_err(report->device, "too many fields in report\n");
return NULL;
}
field = kzalloc((sizeof(struct hid_field) +
usages * sizeof(struct hid_usage) +
usages * sizeof(unsigned)), GFP_KERNEL);
if (!field)
return NULL;
field->index = report->maxfield++;
report->field[field->index] = field;
field->usage = (struct hid_usage *)(field + 1);
field->value = (s32 *)(field->usage + usages);
field->report = report;
return field;
}
/*
* Open a collection. The type/usage is pushed on the stack.
*/
static int open_collection(struct hid_parser *parser, unsigned type)
{
struct hid_collection *collection;
unsigned usage;
int collection_index;
usage = parser->local.usage[0];
if (parser->collection_stack_ptr == parser->collection_stack_size) {
unsigned int *collection_stack;
unsigned int new_size = parser->collection_stack_size +
HID_COLLECTION_STACK_SIZE;
collection_stack = krealloc(parser->collection_stack,
new_size * sizeof(unsigned int),
GFP_KERNEL);
if (!collection_stack)
return -ENOMEM;
parser->collection_stack = collection_stack;
parser->collection_stack_size = new_size;
}
if (parser->device->maxcollection == parser->device->collection_size) {
treewide: kmalloc() -> kmalloc_array() The kmalloc() function has a 2-factor argument form, kmalloc_array(). This patch replaces cases of: kmalloc(a * b, gfp) with: kmalloc_array(a * b, gfp) as well as handling cases of: kmalloc(a * b * c, gfp) with: kmalloc(array3_size(a, b, c), gfp) as it's slightly less ugly than: kmalloc_array(array_size(a, b), c, gfp) This does, however, attempt to ignore constant size factors like: kmalloc(4 * 1024, gfp) though any constants defined via macros get caught up in the conversion. Any factors with a sizeof() of "unsigned char", "char", and "u8" were dropped, since they're redundant. The tools/ directory was manually excluded, since it has its own implementation of kmalloc(). The Coccinelle script used for this was: // Fix redundant parens around sizeof(). @@ type TYPE; expression THING, E; @@ ( kmalloc( - (sizeof(TYPE)) * E + sizeof(TYPE) * E , ...) | kmalloc( - (sizeof(THING)) * E + sizeof(THING) * E , ...) ) // Drop single-byte sizes and redundant parens. @@ expression COUNT; typedef u8; typedef __u8; @@ ( kmalloc( - sizeof(u8) * (COUNT) + COUNT , ...) | kmalloc( - sizeof(__u8) * (COUNT) + COUNT , ...) | kmalloc( - sizeof(char) * (COUNT) + COUNT , ...) | kmalloc( - sizeof(unsigned char) * (COUNT) + COUNT , ...) | kmalloc( - sizeof(u8) * COUNT + COUNT , ...) | kmalloc( - sizeof(__u8) * COUNT + COUNT , ...) | kmalloc( - sizeof(char) * COUNT + COUNT , ...) | kmalloc( - sizeof(unsigned char) * COUNT + COUNT , ...) ) // 2-factor product with sizeof(type/expression) and identifier or constant. @@ type TYPE; expression THING; identifier COUNT_ID; constant COUNT_CONST; @@ ( - kmalloc + kmalloc_array ( - sizeof(TYPE) * (COUNT_ID) + COUNT_ID, sizeof(TYPE) , ...) | - kmalloc + kmalloc_array ( - sizeof(TYPE) * COUNT_ID + COUNT_ID, sizeof(TYPE) , ...) | - kmalloc + kmalloc_array ( - sizeof(TYPE) * (COUNT_CONST) + COUNT_CONST, sizeof(TYPE) , ...) | - kmalloc + kmalloc_array ( - sizeof(TYPE) * COUNT_CONST + COUNT_CONST, sizeof(TYPE) , ...) | - kmalloc + kmalloc_array ( - sizeof(THING) * (COUNT_ID) + COUNT_ID, sizeof(THING) , ...) | - kmalloc + kmalloc_array ( - sizeof(THING) * COUNT_ID + COUNT_ID, sizeof(THING) , ...) | - kmalloc + kmalloc_array ( - sizeof(THING) * (COUNT_CONST) + COUNT_CONST, sizeof(THING) , ...) | - kmalloc + kmalloc_array ( - sizeof(THING) * COUNT_CONST + COUNT_CONST, sizeof(THING) , ...) ) // 2-factor product, only identifiers. @@ identifier SIZE, COUNT; @@ - kmalloc + kmalloc_array ( - SIZE * COUNT + COUNT, SIZE , ...) // 3-factor product with 1 sizeof(type) or sizeof(expression), with // redundant parens removed. @@ expression THING; identifier STRIDE, COUNT; type TYPE; @@ ( kmalloc( - sizeof(TYPE) * (COUNT) * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kmalloc( - sizeof(TYPE) * (COUNT) * STRIDE + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kmalloc( - sizeof(TYPE) * COUNT * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kmalloc( - sizeof(TYPE) * COUNT * STRIDE + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kmalloc( - sizeof(THING) * (COUNT) * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kmalloc( - sizeof(THING) * (COUNT) * STRIDE + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kmalloc( - sizeof(THING) * COUNT * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kmalloc( - sizeof(THING) * COUNT * STRIDE + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) ) // 3-factor product with 2 sizeof(variable), with redundant parens removed. @@ expression THING1, THING2; identifier COUNT; type TYPE1, TYPE2; @@ ( kmalloc( - sizeof(TYPE1) * sizeof(TYPE2) * COUNT + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2)) , ...) | kmalloc( - sizeof(TYPE1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2)) , ...) | kmalloc( - sizeof(THING1) * sizeof(THING2) * COUNT + array3_size(COUNT, sizeof(THING1), sizeof(THING2)) , ...) | kmalloc( - sizeof(THING1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(THING1), sizeof(THING2)) , ...) | kmalloc( - sizeof(TYPE1) * sizeof(THING2) * COUNT + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2)) , ...) | kmalloc( - sizeof(TYPE1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2)) , ...) ) // 3-factor product, only identifiers, with redundant parens removed. @@ identifier STRIDE, SIZE, COUNT; @@ ( kmalloc( - (COUNT) * STRIDE * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - COUNT * (STRIDE) * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - COUNT * STRIDE * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - (COUNT) * (STRIDE) * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - COUNT * (STRIDE) * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - (COUNT) * STRIDE * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - (COUNT) * (STRIDE) * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - COUNT * STRIDE * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) ) // Any remaining multi-factor products, first at least 3-factor products, // when they're not all constants... @@ expression E1, E2, E3; constant C1, C2, C3; @@ ( kmalloc(C1 * C2 * C3, ...) | kmalloc( - (E1) * E2 * E3 + array3_size(E1, E2, E3) , ...) | kmalloc( - (E1) * (E2) * E3 + array3_size(E1, E2, E3) , ...) | kmalloc( - (E1) * (E2) * (E3) + array3_size(E1, E2, E3) , ...) | kmalloc( - E1 * E2 * E3 + array3_size(E1, E2, E3) , ...) ) // And then all remaining 2 factors products when they're not all constants, // keeping sizeof() as the second factor argument. @@ expression THING, E1, E2; type TYPE; constant C1, C2, C3; @@ ( kmalloc(sizeof(THING) * C2, ...) | kmalloc(sizeof(TYPE) * C2, ...) | kmalloc(C1 * C2 * C3, ...) | kmalloc(C1 * C2, ...) | - kmalloc + kmalloc_array ( - sizeof(TYPE) * (E2) + E2, sizeof(TYPE) , ...) | - kmalloc + kmalloc_array ( - sizeof(TYPE) * E2 + E2, sizeof(TYPE) , ...) | - kmalloc + kmalloc_array ( - sizeof(THING) * (E2) + E2, sizeof(THING) , ...) | - kmalloc + kmalloc_array ( - sizeof(THING) * E2 + E2, sizeof(THING) , ...) | - kmalloc + kmalloc_array ( - (E1) * E2 + E1, E2 , ...) | - kmalloc + kmalloc_array ( - (E1) * (E2) + E1, E2 , ...) | - kmalloc + kmalloc_array ( - E1 * E2 + E1, E2 , ...) ) Signed-off-by: Kees Cook <keescook@chromium.org>
2018-06-12 20:55:00 +00:00
collection = kmalloc(
array3_size(sizeof(struct hid_collection),
parser->device->collection_size,
2),
GFP_KERNEL);
if (collection == NULL) {
hid_err(parser->device, "failed to reallocate collection array\n");
return -ENOMEM;
}
memcpy(collection, parser->device->collection,
sizeof(struct hid_collection) *
parser->device->collection_size);
memset(collection + parser->device->collection_size, 0,
sizeof(struct hid_collection) *
parser->device->collection_size);
kfree(parser->device->collection);
parser->device->collection = collection;
parser->device->collection_size *= 2;
}
parser->collection_stack[parser->collection_stack_ptr++] =
parser->device->maxcollection;
collection_index = parser->device->maxcollection++;
collection = parser->device->collection + collection_index;
collection->type = type;
collection->usage = usage;
collection->level = parser->collection_stack_ptr - 1;
collection->parent_idx = (collection->level == 0) ? -1 :
parser->collection_stack[collection->level - 1];
if (type == HID_COLLECTION_APPLICATION)
parser->device->maxapplication++;
return 0;
}
/*
* Close a collection.
*/
static int close_collection(struct hid_parser *parser)
{
if (!parser->collection_stack_ptr) {
hid_err(parser->device, "collection stack underflow\n");
return -EINVAL;
}
parser->collection_stack_ptr--;
return 0;
}
/*
* Climb up the stack, search for the specified collection type
* and return the usage.
*/
static unsigned hid_lookup_collection(struct hid_parser *parser, unsigned type)
{
struct hid_collection *collection = parser->device->collection;
int n;
for (n = parser->collection_stack_ptr - 1; n >= 0; n--) {
unsigned index = parser->collection_stack[n];
if (collection[index].type == type)
return collection[index].usage;
}
return 0; /* we know nothing about this usage type */
}
HID: core: check whether Usage Page item is after Usage ID items Upstream commit 58e75155009c ("HID: core: move Usage Page concatenation to Main item") adds support for Usage Page item after Usage ID items (such as keyboards manufactured by Primax). Usage Page concatenation in Main item works well for following report descriptor patterns: USAGE_PAGE (Keyboard) 05 07 USAGE_MINIMUM (Keyboard LeftControl) 19 E0 USAGE_MAXIMUM (Keyboard Right GUI) 29 E7 LOGICAL_MINIMUM (0) 15 00 LOGICAL_MAXIMUM (1) 25 01 REPORT_SIZE (1) 75 01 REPORT_COUNT (8) 95 08 INPUT (Data,Var,Abs) 81 02 ------------- USAGE_MINIMUM (Keyboard LeftControl) 19 E0 USAGE_MAXIMUM (Keyboard Right GUI) 29 E7 LOGICAL_MINIMUM (0) 15 00 LOGICAL_MAXIMUM (1) 25 01 REPORT_SIZE (1) 75 01 REPORT_COUNT (8) 95 08 USAGE_PAGE (Keyboard) 05 07 INPUT (Data,Var,Abs) 81 02 But it makes the parser act wrong for the following report descriptor pattern(such as some Gamepads): USAGE_PAGE (Button) 05 09 USAGE (Button 1) 09 01 USAGE (Button 2) 09 02 USAGE (Button 4) 09 04 USAGE (Button 5) 09 05 USAGE (Button 7) 09 07 USAGE (Button 8) 09 08 USAGE (Button 14) 09 0E USAGE (Button 15) 09 0F USAGE (Button 13) 09 0D USAGE_PAGE (Consumer Devices) 05 0C USAGE (Back) 0a 24 02 USAGE (HomePage) 0a 23 02 LOGICAL_MINIMUM (0) 15 00 LOGICAL_MAXIMUM (1) 25 01 REPORT_SIZE (1) 75 01 REPORT_COUNT (11) 95 0B INPUT (Data,Var,Abs) 81 02 With Usage Page concatenation in Main item, parser recognizes all the 11 Usages as consumer keys, it is not the HID device's real intention. This patch checks whether Usage Page is really defined after Usage ID items by comparing usage page using status. Usage Page concatenation on currently defined Usage Page will always do in local parsing when Usage ID items encountered. When Main item is parsing, concatenation will do again with last defined Usage Page if this page has not been used in the previous usages concatenation. Signed-off-by: Candle Sun <candle.sun@unisoc.com> Signed-off-by: Nianfu Bai <nianfu.bai@unisoc.com> Benjamin Tissoires <benjamin.tissoires@redhat.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2019-10-22 14:21:39 +00:00
/*
* Concatenate usage which defines 16 bits or less with the
* currently defined usage page to form a 32 bit usage
*/
static void complete_usage(struct hid_parser *parser, unsigned int index)
{
parser->local.usage[index] &= 0xFFFF;
parser->local.usage[index] |=
(parser->global.usage_page & 0xFFFF) << 16;
}
/*
* Add a usage to the temporary parser table.
*/
static int hid_add_usage(struct hid_parser *parser, unsigned usage, u8 size)
{
if (parser->local.usage_index >= HID_MAX_USAGES) {
hid_err(parser->device, "usage index exceeded\n");
return -1;
}
parser->local.usage[parser->local.usage_index] = usage;
HID: core: check whether Usage Page item is after Usage ID items Upstream commit 58e75155009c ("HID: core: move Usage Page concatenation to Main item") adds support for Usage Page item after Usage ID items (such as keyboards manufactured by Primax). Usage Page concatenation in Main item works well for following report descriptor patterns: USAGE_PAGE (Keyboard) 05 07 USAGE_MINIMUM (Keyboard LeftControl) 19 E0 USAGE_MAXIMUM (Keyboard Right GUI) 29 E7 LOGICAL_MINIMUM (0) 15 00 LOGICAL_MAXIMUM (1) 25 01 REPORT_SIZE (1) 75 01 REPORT_COUNT (8) 95 08 INPUT (Data,Var,Abs) 81 02 ------------- USAGE_MINIMUM (Keyboard LeftControl) 19 E0 USAGE_MAXIMUM (Keyboard Right GUI) 29 E7 LOGICAL_MINIMUM (0) 15 00 LOGICAL_MAXIMUM (1) 25 01 REPORT_SIZE (1) 75 01 REPORT_COUNT (8) 95 08 USAGE_PAGE (Keyboard) 05 07 INPUT (Data,Var,Abs) 81 02 But it makes the parser act wrong for the following report descriptor pattern(such as some Gamepads): USAGE_PAGE (Button) 05 09 USAGE (Button 1) 09 01 USAGE (Button 2) 09 02 USAGE (Button 4) 09 04 USAGE (Button 5) 09 05 USAGE (Button 7) 09 07 USAGE (Button 8) 09 08 USAGE (Button 14) 09 0E USAGE (Button 15) 09 0F USAGE (Button 13) 09 0D USAGE_PAGE (Consumer Devices) 05 0C USAGE (Back) 0a 24 02 USAGE (HomePage) 0a 23 02 LOGICAL_MINIMUM (0) 15 00 LOGICAL_MAXIMUM (1) 25 01 REPORT_SIZE (1) 75 01 REPORT_COUNT (11) 95 0B INPUT (Data,Var,Abs) 81 02 With Usage Page concatenation in Main item, parser recognizes all the 11 Usages as consumer keys, it is not the HID device's real intention. This patch checks whether Usage Page is really defined after Usage ID items by comparing usage page using status. Usage Page concatenation on currently defined Usage Page will always do in local parsing when Usage ID items encountered. When Main item is parsing, concatenation will do again with last defined Usage Page if this page has not been used in the previous usages concatenation. Signed-off-by: Candle Sun <candle.sun@unisoc.com> Signed-off-by: Nianfu Bai <nianfu.bai@unisoc.com> Benjamin Tissoires <benjamin.tissoires@redhat.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2019-10-22 14:21:39 +00:00
/*
* If Usage item only includes usage id, concatenate it with
* currently defined usage page
*/
if (size <= 2)
complete_usage(parser, parser->local.usage_index);
parser->local.usage_size[parser->local.usage_index] = size;
parser->local.collection_index[parser->local.usage_index] =
parser->collection_stack_ptr ?
parser->collection_stack[parser->collection_stack_ptr - 1] : 0;
parser->local.usage_index++;
return 0;
}
/*
* Register a new field for this report.
*/
static int hid_add_field(struct hid_parser *parser, unsigned report_type, unsigned flags)
{
struct hid_report *report;
struct hid_field *field;
unsigned int usages;
unsigned int offset;
unsigned int i;
unsigned int application;
application = hid_lookup_collection(parser, HID_COLLECTION_APPLICATION);
report = hid_register_report(parser->device, report_type,
parser->global.report_id, application);
if (!report) {
hid_err(parser->device, "hid_register_report failed\n");
return -1;
}
/* Handle both signed and unsigned cases properly */
if ((parser->global.logical_minimum < 0 &&
parser->global.logical_maximum <
parser->global.logical_minimum) ||
(parser->global.logical_minimum >= 0 &&
(__u32)parser->global.logical_maximum <
(__u32)parser->global.logical_minimum)) {
dbg_hid("logical range invalid 0x%x 0x%x\n",
parser->global.logical_minimum,
parser->global.logical_maximum);
return -1;
}
offset = report->size;
report->size += parser->global.report_size * parser->global.report_count;
/* Total size check: Allow for possible report index byte */
if (report->size > (HID_MAX_BUFFER_SIZE - 1) << 3) {
hid_err(parser->device, "report is too long\n");
return -1;
}
if (!parser->local.usage_index) /* Ignore padding fields */
return 0;
usages = max_t(unsigned, parser->local.usage_index,
parser->global.report_count);
field = hid_register_field(report, usages);
if (!field)
return 0;
field->physical = hid_lookup_collection(parser, HID_COLLECTION_PHYSICAL);
field->logical = hid_lookup_collection(parser, HID_COLLECTION_LOGICAL);
field->application = application;
for (i = 0; i < usages; i++) {
unsigned j = i;
/* Duplicate the last usage we parsed if we have excess values */
if (i >= parser->local.usage_index)
j = parser->local.usage_index - 1;
field->usage[i].hid = parser->local.usage[j];
field->usage[i].collection_index =
parser->local.collection_index[j];
field->usage[i].usage_index = i;
field->usage[i].resolution_multiplier = 1;
}
field->maxusage = usages;
field->flags = flags;
field->report_offset = offset;
field->report_type = report_type;
field->report_size = parser->global.report_size;
field->report_count = parser->global.report_count;
field->logical_minimum = parser->global.logical_minimum;
field->logical_maximum = parser->global.logical_maximum;
field->physical_minimum = parser->global.physical_minimum;
field->physical_maximum = parser->global.physical_maximum;
field->unit_exponent = parser->global.unit_exponent;
field->unit = parser->global.unit;
return 0;
}
/*
* Read data value from item.
*/
static u32 item_udata(struct hid_item *item)
{
switch (item->size) {
case 1: return item->data.u8;
case 2: return item->data.u16;
case 4: return item->data.u32;
}
return 0;
}
static s32 item_sdata(struct hid_item *item)
{
switch (item->size) {
case 1: return item->data.s8;
case 2: return item->data.s16;
case 4: return item->data.s32;
}
return 0;
}
/*
* Process a global item.
*/
static int hid_parser_global(struct hid_parser *parser, struct hid_item *item)
{
HID: Fix unit exponent parsing again Revert some changes done in 774638386826621c984ab6994439f474709cac5e. Revert all changes done in hidinput_calc_abs_res as it mistakingly used "Unit" item exponent nibbles to affect resolution value. This wasn't breaking resolution calculation of relevant axes of any existing devices, though, as they have only one dimension to their units and thus 1 in the corresponding nible. Revert to reading "Unit Exponent" item value as a signed integer in hid_parser_global to fix reading specification-complying values. This fixes resolution calculation of devices complying to the HID standard, including Huion, KYE, Waltop and UC-Logic graphics tablets which have their report descriptors fixed by the drivers. Explanations follow. There are two "unit exponents" in HID specification and it is important not to mix them. One is the global "Unit Exponent" item and another is nibble values in the global "Unit" item. See 6.2.2.7 Global Items. The "Unit Exponent" value is just a signed integer and is used to scale the integer resolution unit values, so fractions can be expressed. The nibbles of "Unit" value are used to select the unit system (nibble 0), and presence of a particular basic unit type in the unit formula and its *exponent* (or power, nibbles 1-6). And yes, the latter is in two complement and zero means absence of the unit type. Taking the representation example of (integer) joules from the specification: [mass(grams)][length(centimeters)^2][time(seconds)^-2] * 10^-7 the "Unit Exponent" would be -7 (or 0xF9, if stored as a byte) and the "Unit" value would be 0xE121, signifying: Nibble Part Value Meaning ----- ---- ----- ------- 0 System 1 SI Linear 1 Length 2 Centimeters^2 2 Mass 1 Grams 3 Time -2 Seconds^-2 To give the resolution in e.g. hundredth of joules the "Unit Exponent" item value should have been -9. See also the examples of "Unit" values for some common units in the same chapter. However, there is a common misunderstanding about the "Unit Exponent" value encoding, where it is assumed to be stored the same as nibbles in "Unit" item. This is most likely due to the specification being a bit vague and overloading the term "unit exponent". This also was and still is proliferated by the official "HID Descriptor Tool", which makes this mistake and stores "Unit Exponent" as such. This format is also mentioned in books such as "USB Complete" and in Microsoft's hardware design guides. As a result many devices currently on the market use this encoding and so the driver should support them. Signed-off-by: Nikolai Kondrashov <spbnick@gmail.com> Acked-by: Benjamin Tissoires <benjamin.tissoires@redhat.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2013-10-13 12:09:52 +00:00
__s32 raw_value;
switch (item->tag) {
case HID_GLOBAL_ITEM_TAG_PUSH:
if (parser->global_stack_ptr == HID_GLOBAL_STACK_SIZE) {
hid_err(parser->device, "global environment stack overflow\n");
return -1;
}
memcpy(parser->global_stack + parser->global_stack_ptr++,
&parser->global, sizeof(struct hid_global));
return 0;
case HID_GLOBAL_ITEM_TAG_POP:
if (!parser->global_stack_ptr) {
hid_err(parser->device, "global environment stack underflow\n");
return -1;
}
memcpy(&parser->global, parser->global_stack +
--parser->global_stack_ptr, sizeof(struct hid_global));
return 0;
case HID_GLOBAL_ITEM_TAG_USAGE_PAGE:
parser->global.usage_page = item_udata(item);
return 0;
case HID_GLOBAL_ITEM_TAG_LOGICAL_MINIMUM:
parser->global.logical_minimum = item_sdata(item);
return 0;
case HID_GLOBAL_ITEM_TAG_LOGICAL_MAXIMUM:
if (parser->global.logical_minimum < 0)
parser->global.logical_maximum = item_sdata(item);
else
parser->global.logical_maximum = item_udata(item);
return 0;
case HID_GLOBAL_ITEM_TAG_PHYSICAL_MINIMUM:
parser->global.physical_minimum = item_sdata(item);
return 0;
case HID_GLOBAL_ITEM_TAG_PHYSICAL_MAXIMUM:
if (parser->global.physical_minimum < 0)
parser->global.physical_maximum = item_sdata(item);
else
parser->global.physical_maximum = item_udata(item);
return 0;
case HID_GLOBAL_ITEM_TAG_UNIT_EXPONENT:
HID: Fix unit exponent parsing again Revert some changes done in 774638386826621c984ab6994439f474709cac5e. Revert all changes done in hidinput_calc_abs_res as it mistakingly used "Unit" item exponent nibbles to affect resolution value. This wasn't breaking resolution calculation of relevant axes of any existing devices, though, as they have only one dimension to their units and thus 1 in the corresponding nible. Revert to reading "Unit Exponent" item value as a signed integer in hid_parser_global to fix reading specification-complying values. This fixes resolution calculation of devices complying to the HID standard, including Huion, KYE, Waltop and UC-Logic graphics tablets which have their report descriptors fixed by the drivers. Explanations follow. There are two "unit exponents" in HID specification and it is important not to mix them. One is the global "Unit Exponent" item and another is nibble values in the global "Unit" item. See 6.2.2.7 Global Items. The "Unit Exponent" value is just a signed integer and is used to scale the integer resolution unit values, so fractions can be expressed. The nibbles of "Unit" value are used to select the unit system (nibble 0), and presence of a particular basic unit type in the unit formula and its *exponent* (or power, nibbles 1-6). And yes, the latter is in two complement and zero means absence of the unit type. Taking the representation example of (integer) joules from the specification: [mass(grams)][length(centimeters)^2][time(seconds)^-2] * 10^-7 the "Unit Exponent" would be -7 (or 0xF9, if stored as a byte) and the "Unit" value would be 0xE121, signifying: Nibble Part Value Meaning ----- ---- ----- ------- 0 System 1 SI Linear 1 Length 2 Centimeters^2 2 Mass 1 Grams 3 Time -2 Seconds^-2 To give the resolution in e.g. hundredth of joules the "Unit Exponent" item value should have been -9. See also the examples of "Unit" values for some common units in the same chapter. However, there is a common misunderstanding about the "Unit Exponent" value encoding, where it is assumed to be stored the same as nibbles in "Unit" item. This is most likely due to the specification being a bit vague and overloading the term "unit exponent". This also was and still is proliferated by the official "HID Descriptor Tool", which makes this mistake and stores "Unit Exponent" as such. This format is also mentioned in books such as "USB Complete" and in Microsoft's hardware design guides. As a result many devices currently on the market use this encoding and so the driver should support them. Signed-off-by: Nikolai Kondrashov <spbnick@gmail.com> Acked-by: Benjamin Tissoires <benjamin.tissoires@redhat.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2013-10-13 12:09:52 +00:00
/* Many devices provide unit exponent as a two's complement
* nibble due to the common misunderstanding of HID
* specification 1.11, 6.2.2.7 Global Items. Attempt to handle
* both this and the standard encoding. */
raw_value = item_sdata(item);
if (!(raw_value & 0xfffffff0))
parser->global.unit_exponent = hid_snto32(raw_value, 4);
else
parser->global.unit_exponent = raw_value;
return 0;
case HID_GLOBAL_ITEM_TAG_UNIT:
parser->global.unit = item_udata(item);
return 0;
case HID_GLOBAL_ITEM_TAG_REPORT_SIZE:
parser->global.report_size = item_udata(item);
if (parser->global.report_size > 256) {
hid_err(parser->device, "invalid report_size %d\n",
parser->global.report_size);
return -1;
}
return 0;
case HID_GLOBAL_ITEM_TAG_REPORT_COUNT:
parser->global.report_count = item_udata(item);
if (parser->global.report_count > HID_MAX_USAGES) {
hid_err(parser->device, "invalid report_count %d\n",
parser->global.report_count);
return -1;
}
return 0;
case HID_GLOBAL_ITEM_TAG_REPORT_ID:
parser->global.report_id = item_udata(item);
if (parser->global.report_id == 0 ||
parser->global.report_id >= HID_MAX_IDS) {
hid_err(parser->device, "report_id %u is invalid\n",
parser->global.report_id);
return -1;
}
return 0;
default:
hid_err(parser->device, "unknown global tag 0x%x\n", item->tag);
return -1;
}
}
/*
* Process a local item.
*/
static int hid_parser_local(struct hid_parser *parser, struct hid_item *item)
{
__u32 data;
unsigned n;
__u32 count;
data = item_udata(item);
switch (item->tag) {
case HID_LOCAL_ITEM_TAG_DELIMITER:
if (data) {
/*
* We treat items before the first delimiter
* as global to all usage sets (branch 0).
* In the moment we process only these global
* items and the first delimiter set.
*/
if (parser->local.delimiter_depth != 0) {
hid_err(parser->device, "nested delimiters\n");
return -1;
}
parser->local.delimiter_depth++;
parser->local.delimiter_branch++;
} else {
if (parser->local.delimiter_depth < 1) {
hid_err(parser->device, "bogus close delimiter\n");
return -1;
}
parser->local.delimiter_depth--;
}
return 0;
case HID_LOCAL_ITEM_TAG_USAGE:
if (parser->local.delimiter_branch > 1) {
dbg_hid("alternative usage ignored\n");
return 0;
}
return hid_add_usage(parser, data, item->size);
case HID_LOCAL_ITEM_TAG_USAGE_MINIMUM:
if (parser->local.delimiter_branch > 1) {
dbg_hid("alternative usage ignored\n");
return 0;
}
parser->local.usage_minimum = data;
return 0;
case HID_LOCAL_ITEM_TAG_USAGE_MAXIMUM:
if (parser->local.delimiter_branch > 1) {
dbg_hid("alternative usage ignored\n");
return 0;
}
count = data - parser->local.usage_minimum;
if (count + parser->local.usage_index >= HID_MAX_USAGES) {
/*
* We do not warn if the name is not set, we are
* actually pre-scanning the device.
*/
if (dev_name(&parser->device->dev))
hid_warn(parser->device,
"ignoring exceeding usage max\n");
data = HID_MAX_USAGES - parser->local.usage_index +
parser->local.usage_minimum - 1;
if (data <= 0) {
hid_err(parser->device,
"no more usage index available\n");
return -1;
}
}
for (n = parser->local.usage_minimum; n <= data; n++)
if (hid_add_usage(parser, n, item->size)) {
dbg_hid("hid_add_usage failed\n");
return -1;
}
return 0;
default:
dbg_hid("unknown local item tag 0x%x\n", item->tag);
return 0;
}
return 0;
}
/*
* Concatenate Usage Pages into Usages where relevant:
* As per specification, 6.2.2.8: "When the parser encounters a main item it
* concatenates the last declared Usage Page with a Usage to form a complete
* usage value."
*/
HID: core: check whether Usage Page item is after Usage ID items Upstream commit 58e75155009c ("HID: core: move Usage Page concatenation to Main item") adds support for Usage Page item after Usage ID items (such as keyboards manufactured by Primax). Usage Page concatenation in Main item works well for following report descriptor patterns: USAGE_PAGE (Keyboard) 05 07 USAGE_MINIMUM (Keyboard LeftControl) 19 E0 USAGE_MAXIMUM (Keyboard Right GUI) 29 E7 LOGICAL_MINIMUM (0) 15 00 LOGICAL_MAXIMUM (1) 25 01 REPORT_SIZE (1) 75 01 REPORT_COUNT (8) 95 08 INPUT (Data,Var,Abs) 81 02 ------------- USAGE_MINIMUM (Keyboard LeftControl) 19 E0 USAGE_MAXIMUM (Keyboard Right GUI) 29 E7 LOGICAL_MINIMUM (0) 15 00 LOGICAL_MAXIMUM (1) 25 01 REPORT_SIZE (1) 75 01 REPORT_COUNT (8) 95 08 USAGE_PAGE (Keyboard) 05 07 INPUT (Data,Var,Abs) 81 02 But it makes the parser act wrong for the following report descriptor pattern(such as some Gamepads): USAGE_PAGE (Button) 05 09 USAGE (Button 1) 09 01 USAGE (Button 2) 09 02 USAGE (Button 4) 09 04 USAGE (Button 5) 09 05 USAGE (Button 7) 09 07 USAGE (Button 8) 09 08 USAGE (Button 14) 09 0E USAGE (Button 15) 09 0F USAGE (Button 13) 09 0D USAGE_PAGE (Consumer Devices) 05 0C USAGE (Back) 0a 24 02 USAGE (HomePage) 0a 23 02 LOGICAL_MINIMUM (0) 15 00 LOGICAL_MAXIMUM (1) 25 01 REPORT_SIZE (1) 75 01 REPORT_COUNT (11) 95 0B INPUT (Data,Var,Abs) 81 02 With Usage Page concatenation in Main item, parser recognizes all the 11 Usages as consumer keys, it is not the HID device's real intention. This patch checks whether Usage Page is really defined after Usage ID items by comparing usage page using status. Usage Page concatenation on currently defined Usage Page will always do in local parsing when Usage ID items encountered. When Main item is parsing, concatenation will do again with last defined Usage Page if this page has not been used in the previous usages concatenation. Signed-off-by: Candle Sun <candle.sun@unisoc.com> Signed-off-by: Nianfu Bai <nianfu.bai@unisoc.com> Benjamin Tissoires <benjamin.tissoires@redhat.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2019-10-22 14:21:39 +00:00
static void hid_concatenate_last_usage_page(struct hid_parser *parser)
{
int i;
HID: core: check whether Usage Page item is after Usage ID items Upstream commit 58e75155009c ("HID: core: move Usage Page concatenation to Main item") adds support for Usage Page item after Usage ID items (such as keyboards manufactured by Primax). Usage Page concatenation in Main item works well for following report descriptor patterns: USAGE_PAGE (Keyboard) 05 07 USAGE_MINIMUM (Keyboard LeftControl) 19 E0 USAGE_MAXIMUM (Keyboard Right GUI) 29 E7 LOGICAL_MINIMUM (0) 15 00 LOGICAL_MAXIMUM (1) 25 01 REPORT_SIZE (1) 75 01 REPORT_COUNT (8) 95 08 INPUT (Data,Var,Abs) 81 02 ------------- USAGE_MINIMUM (Keyboard LeftControl) 19 E0 USAGE_MAXIMUM (Keyboard Right GUI) 29 E7 LOGICAL_MINIMUM (0) 15 00 LOGICAL_MAXIMUM (1) 25 01 REPORT_SIZE (1) 75 01 REPORT_COUNT (8) 95 08 USAGE_PAGE (Keyboard) 05 07 INPUT (Data,Var,Abs) 81 02 But it makes the parser act wrong for the following report descriptor pattern(such as some Gamepads): USAGE_PAGE (Button) 05 09 USAGE (Button 1) 09 01 USAGE (Button 2) 09 02 USAGE (Button 4) 09 04 USAGE (Button 5) 09 05 USAGE (Button 7) 09 07 USAGE (Button 8) 09 08 USAGE (Button 14) 09 0E USAGE (Button 15) 09 0F USAGE (Button 13) 09 0D USAGE_PAGE (Consumer Devices) 05 0C USAGE (Back) 0a 24 02 USAGE (HomePage) 0a 23 02 LOGICAL_MINIMUM (0) 15 00 LOGICAL_MAXIMUM (1) 25 01 REPORT_SIZE (1) 75 01 REPORT_COUNT (11) 95 0B INPUT (Data,Var,Abs) 81 02 With Usage Page concatenation in Main item, parser recognizes all the 11 Usages as consumer keys, it is not the HID device's real intention. This patch checks whether Usage Page is really defined after Usage ID items by comparing usage page using status. Usage Page concatenation on currently defined Usage Page will always do in local parsing when Usage ID items encountered. When Main item is parsing, concatenation will do again with last defined Usage Page if this page has not been used in the previous usages concatenation. Signed-off-by: Candle Sun <candle.sun@unisoc.com> Signed-off-by: Nianfu Bai <nianfu.bai@unisoc.com> Benjamin Tissoires <benjamin.tissoires@redhat.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2019-10-22 14:21:39 +00:00
unsigned int usage_page;
unsigned int current_page;
if (!parser->local.usage_index)
return;
usage_page = parser->global.usage_page;
/*
* Concatenate usage page again only if last declared Usage Page
* has not been already used in previous usages concatenation
*/
for (i = parser->local.usage_index - 1; i >= 0; i--) {
if (parser->local.usage_size[i] > 2)
/* Ignore extended usages */
continue;
HID: core: check whether Usage Page item is after Usage ID items Upstream commit 58e75155009c ("HID: core: move Usage Page concatenation to Main item") adds support for Usage Page item after Usage ID items (such as keyboards manufactured by Primax). Usage Page concatenation in Main item works well for following report descriptor patterns: USAGE_PAGE (Keyboard) 05 07 USAGE_MINIMUM (Keyboard LeftControl) 19 E0 USAGE_MAXIMUM (Keyboard Right GUI) 29 E7 LOGICAL_MINIMUM (0) 15 00 LOGICAL_MAXIMUM (1) 25 01 REPORT_SIZE (1) 75 01 REPORT_COUNT (8) 95 08 INPUT (Data,Var,Abs) 81 02 ------------- USAGE_MINIMUM (Keyboard LeftControl) 19 E0 USAGE_MAXIMUM (Keyboard Right GUI) 29 E7 LOGICAL_MINIMUM (0) 15 00 LOGICAL_MAXIMUM (1) 25 01 REPORT_SIZE (1) 75 01 REPORT_COUNT (8) 95 08 USAGE_PAGE (Keyboard) 05 07 INPUT (Data,Var,Abs) 81 02 But it makes the parser act wrong for the following report descriptor pattern(such as some Gamepads): USAGE_PAGE (Button) 05 09 USAGE (Button 1) 09 01 USAGE (Button 2) 09 02 USAGE (Button 4) 09 04 USAGE (Button 5) 09 05 USAGE (Button 7) 09 07 USAGE (Button 8) 09 08 USAGE (Button 14) 09 0E USAGE (Button 15) 09 0F USAGE (Button 13) 09 0D USAGE_PAGE (Consumer Devices) 05 0C USAGE (Back) 0a 24 02 USAGE (HomePage) 0a 23 02 LOGICAL_MINIMUM (0) 15 00 LOGICAL_MAXIMUM (1) 25 01 REPORT_SIZE (1) 75 01 REPORT_COUNT (11) 95 0B INPUT (Data,Var,Abs) 81 02 With Usage Page concatenation in Main item, parser recognizes all the 11 Usages as consumer keys, it is not the HID device's real intention. This patch checks whether Usage Page is really defined after Usage ID items by comparing usage page using status. Usage Page concatenation on currently defined Usage Page will always do in local parsing when Usage ID items encountered. When Main item is parsing, concatenation will do again with last defined Usage Page if this page has not been used in the previous usages concatenation. Signed-off-by: Candle Sun <candle.sun@unisoc.com> Signed-off-by: Nianfu Bai <nianfu.bai@unisoc.com> Benjamin Tissoires <benjamin.tissoires@redhat.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2019-10-22 14:21:39 +00:00
current_page = parser->local.usage[i] >> 16;
if (current_page == usage_page)
break;
complete_usage(parser, i);
}
}
/*
* Process a main item.
*/
static int hid_parser_main(struct hid_parser *parser, struct hid_item *item)
{
__u32 data;
int ret;
HID: core: check whether Usage Page item is after Usage ID items Upstream commit 58e75155009c ("HID: core: move Usage Page concatenation to Main item") adds support for Usage Page item after Usage ID items (such as keyboards manufactured by Primax). Usage Page concatenation in Main item works well for following report descriptor patterns: USAGE_PAGE (Keyboard) 05 07 USAGE_MINIMUM (Keyboard LeftControl) 19 E0 USAGE_MAXIMUM (Keyboard Right GUI) 29 E7 LOGICAL_MINIMUM (0) 15 00 LOGICAL_MAXIMUM (1) 25 01 REPORT_SIZE (1) 75 01 REPORT_COUNT (8) 95 08 INPUT (Data,Var,Abs) 81 02 ------------- USAGE_MINIMUM (Keyboard LeftControl) 19 E0 USAGE_MAXIMUM (Keyboard Right GUI) 29 E7 LOGICAL_MINIMUM (0) 15 00 LOGICAL_MAXIMUM (1) 25 01 REPORT_SIZE (1) 75 01 REPORT_COUNT (8) 95 08 USAGE_PAGE (Keyboard) 05 07 INPUT (Data,Var,Abs) 81 02 But it makes the parser act wrong for the following report descriptor pattern(such as some Gamepads): USAGE_PAGE (Button) 05 09 USAGE (Button 1) 09 01 USAGE (Button 2) 09 02 USAGE (Button 4) 09 04 USAGE (Button 5) 09 05 USAGE (Button 7) 09 07 USAGE (Button 8) 09 08 USAGE (Button 14) 09 0E USAGE (Button 15) 09 0F USAGE (Button 13) 09 0D USAGE_PAGE (Consumer Devices) 05 0C USAGE (Back) 0a 24 02 USAGE (HomePage) 0a 23 02 LOGICAL_MINIMUM (0) 15 00 LOGICAL_MAXIMUM (1) 25 01 REPORT_SIZE (1) 75 01 REPORT_COUNT (11) 95 0B INPUT (Data,Var,Abs) 81 02 With Usage Page concatenation in Main item, parser recognizes all the 11 Usages as consumer keys, it is not the HID device's real intention. This patch checks whether Usage Page is really defined after Usage ID items by comparing usage page using status. Usage Page concatenation on currently defined Usage Page will always do in local parsing when Usage ID items encountered. When Main item is parsing, concatenation will do again with last defined Usage Page if this page has not been used in the previous usages concatenation. Signed-off-by: Candle Sun <candle.sun@unisoc.com> Signed-off-by: Nianfu Bai <nianfu.bai@unisoc.com> Benjamin Tissoires <benjamin.tissoires@redhat.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2019-10-22 14:21:39 +00:00
hid_concatenate_last_usage_page(parser);
data = item_udata(item);
switch (item->tag) {
case HID_MAIN_ITEM_TAG_BEGIN_COLLECTION:
ret = open_collection(parser, data & 0xff);
break;
case HID_MAIN_ITEM_TAG_END_COLLECTION:
ret = close_collection(parser);
break;
case HID_MAIN_ITEM_TAG_INPUT:
ret = hid_add_field(parser, HID_INPUT_REPORT, data);
break;
case HID_MAIN_ITEM_TAG_OUTPUT:
ret = hid_add_field(parser, HID_OUTPUT_REPORT, data);
break;
case HID_MAIN_ITEM_TAG_FEATURE:
ret = hid_add_field(parser, HID_FEATURE_REPORT, data);
break;
default:
hid_warn(parser->device, "unknown main item tag 0x%x\n", item->tag);
ret = 0;
}
memset(&parser->local, 0, sizeof(parser->local)); /* Reset the local parser environment */
return ret;
}
/*
* Process a reserved item.
*/
static int hid_parser_reserved(struct hid_parser *parser, struct hid_item *item)
{
dbg_hid("reserved item type, tag 0x%x\n", item->tag);
return 0;
}
/*
* Free a report and all registered fields. The field->usage and
* field->value table's are allocated behind the field, so we need
* only to free(field) itself.
*/
static void hid_free_report(struct hid_report *report)
{
unsigned n;
for (n = 0; n < report->maxfield; n++)
kfree(report->field[n]);
kfree(report);
}
/*
* Close report. This function returns the device
* state to the point prior to hid_open_report().
*/
static void hid_close_report(struct hid_device *device)
{
unsigned i, j;
for (i = 0; i < HID_REPORT_TYPES; i++) {
struct hid_report_enum *report_enum = device->report_enum + i;
for (j = 0; j < HID_MAX_IDS; j++) {
struct hid_report *report = report_enum->report_id_hash[j];
if (report)
hid_free_report(report);
}
memset(report_enum, 0, sizeof(*report_enum));
INIT_LIST_HEAD(&report_enum->report_list);
}
kfree(device->rdesc);
device->rdesc = NULL;
device->rsize = 0;
kfree(device->collection);
device->collection = NULL;
device->collection_size = 0;
device->maxcollection = 0;
device->maxapplication = 0;
device->status &= ~HID_STAT_PARSED;
}
/*
* Free a device structure, all reports, and all fields.
*/
static void hid_device_release(struct device *dev)
{
struct hid_device *hid = to_hid_device(dev);
hid_close_report(hid);
kfree(hid->dev_rdesc);
kfree(hid);
}
/*
* Fetch a report description item from the data stream. We support long
* items, though they are not used yet.
*/
static u8 *fetch_item(__u8 *start, __u8 *end, struct hid_item *item)
{
u8 b;
if ((end - start) <= 0)
return NULL;
b = *start++;
item->type = (b >> 2) & 3;
item->tag = (b >> 4) & 15;
if (item->tag == HID_ITEM_TAG_LONG) {
item->format = HID_ITEM_FORMAT_LONG;
if ((end - start) < 2)
return NULL;
item->size = *start++;
item->tag = *start++;
if ((end - start) < item->size)
return NULL;
item->data.longdata = start;
start += item->size;
return start;
}
item->format = HID_ITEM_FORMAT_SHORT;
item->size = b & 3;
switch (item->size) {
case 0:
return start;
case 1:
if ((end - start) < 1)
return NULL;
item->data.u8 = *start++;
return start;
case 2:
if ((end - start) < 2)
return NULL;
item->data.u16 = get_unaligned_le16(start);
start = (__u8 *)((__le16 *)start + 1);
return start;
case 3:
item->size++;
if ((end - start) < 4)
return NULL;
item->data.u32 = get_unaligned_le32(start);
start = (__u8 *)((__le32 *)start + 1);
return start;
}
return NULL;
}
static void hid_scan_input_usage(struct hid_parser *parser, u32 usage)
{
struct hid_device *hid = parser->device;
if (usage == HID_DG_CONTACTID)
hid->group = HID_GROUP_MULTITOUCH;
}
static void hid_scan_feature_usage(struct hid_parser *parser, u32 usage)
{
if (usage == 0xff0000c5 && parser->global.report_count == 256 &&
parser->global.report_size == 8)
parser->scan_flags |= HID_SCAN_FLAG_MT_WIN_8;
if (usage == 0xff0000c6 && parser->global.report_count == 1 &&
parser->global.report_size == 8)
parser->scan_flags |= HID_SCAN_FLAG_MT_WIN_8;
}
static void hid_scan_collection(struct hid_parser *parser, unsigned type)
{
struct hid_device *hid = parser->device;
int i;
if (((parser->global.usage_page << 16) == HID_UP_SENSOR) &&
type == HID_COLLECTION_PHYSICAL)
hid->group = HID_GROUP_SENSOR_HUB;
if (hid->vendor == USB_VENDOR_ID_MICROSOFT &&
hid->product == USB_DEVICE_ID_MS_POWER_COVER &&
hid->group == HID_GROUP_MULTITOUCH)
hid->group = HID_GROUP_GENERIC;
if ((parser->global.usage_page << 16) == HID_UP_GENDESK)
for (i = 0; i < parser->local.usage_index; i++)
if (parser->local.usage[i] == HID_GD_POINTER)
parser->scan_flags |= HID_SCAN_FLAG_GD_POINTER;
if ((parser->global.usage_page << 16) >= HID_UP_MSVENDOR)
parser->scan_flags |= HID_SCAN_FLAG_VENDOR_SPECIFIC;
if ((parser->global.usage_page << 16) == HID_UP_GOOGLEVENDOR)
for (i = 0; i < parser->local.usage_index; i++)
if (parser->local.usage[i] ==
(HID_UP_GOOGLEVENDOR | 0x0001))
parser->device->group =
HID_GROUP_VIVALDI;
}
static int hid_scan_main(struct hid_parser *parser, struct hid_item *item)
{
__u32 data;
int i;
HID: core: check whether Usage Page item is after Usage ID items Upstream commit 58e75155009c ("HID: core: move Usage Page concatenation to Main item") adds support for Usage Page item after Usage ID items (such as keyboards manufactured by Primax). Usage Page concatenation in Main item works well for following report descriptor patterns: USAGE_PAGE (Keyboard) 05 07 USAGE_MINIMUM (Keyboard LeftControl) 19 E0 USAGE_MAXIMUM (Keyboard Right GUI) 29 E7 LOGICAL_MINIMUM (0) 15 00 LOGICAL_MAXIMUM (1) 25 01 REPORT_SIZE (1) 75 01 REPORT_COUNT (8) 95 08 INPUT (Data,Var,Abs) 81 02 ------------- USAGE_MINIMUM (Keyboard LeftControl) 19 E0 USAGE_MAXIMUM (Keyboard Right GUI) 29 E7 LOGICAL_MINIMUM (0) 15 00 LOGICAL_MAXIMUM (1) 25 01 REPORT_SIZE (1) 75 01 REPORT_COUNT (8) 95 08 USAGE_PAGE (Keyboard) 05 07 INPUT (Data,Var,Abs) 81 02 But it makes the parser act wrong for the following report descriptor pattern(such as some Gamepads): USAGE_PAGE (Button) 05 09 USAGE (Button 1) 09 01 USAGE (Button 2) 09 02 USAGE (Button 4) 09 04 USAGE (Button 5) 09 05 USAGE (Button 7) 09 07 USAGE (Button 8) 09 08 USAGE (Button 14) 09 0E USAGE (Button 15) 09 0F USAGE (Button 13) 09 0D USAGE_PAGE (Consumer Devices) 05 0C USAGE (Back) 0a 24 02 USAGE (HomePage) 0a 23 02 LOGICAL_MINIMUM (0) 15 00 LOGICAL_MAXIMUM (1) 25 01 REPORT_SIZE (1) 75 01 REPORT_COUNT (11) 95 0B INPUT (Data,Var,Abs) 81 02 With Usage Page concatenation in Main item, parser recognizes all the 11 Usages as consumer keys, it is not the HID device's real intention. This patch checks whether Usage Page is really defined after Usage ID items by comparing usage page using status. Usage Page concatenation on currently defined Usage Page will always do in local parsing when Usage ID items encountered. When Main item is parsing, concatenation will do again with last defined Usage Page if this page has not been used in the previous usages concatenation. Signed-off-by: Candle Sun <candle.sun@unisoc.com> Signed-off-by: Nianfu Bai <nianfu.bai@unisoc.com> Benjamin Tissoires <benjamin.tissoires@redhat.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2019-10-22 14:21:39 +00:00
hid_concatenate_last_usage_page(parser);
data = item_udata(item);
switch (item->tag) {
case HID_MAIN_ITEM_TAG_BEGIN_COLLECTION:
hid_scan_collection(parser, data & 0xff);
break;
case HID_MAIN_ITEM_TAG_END_COLLECTION:
break;
case HID_MAIN_ITEM_TAG_INPUT:
/* ignore constant inputs, they will be ignored by hid-input */
if (data & HID_MAIN_ITEM_CONSTANT)
break;
for (i = 0; i < parser->local.usage_index; i++)
hid_scan_input_usage(parser, parser->local.usage[i]);
break;
case HID_MAIN_ITEM_TAG_OUTPUT:
break;
case HID_MAIN_ITEM_TAG_FEATURE:
for (i = 0; i < parser->local.usage_index; i++)
hid_scan_feature_usage(parser, parser->local.usage[i]);
break;
}
/* Reset the local parser environment */
memset(&parser->local, 0, sizeof(parser->local));
return 0;
}
/*
* Scan a report descriptor before the device is added to the bus.
* Sets device groups and other properties that determine what driver
* to load.
*/
static int hid_scan_report(struct hid_device *hid)
{
struct hid_parser *parser;
struct hid_item item;
__u8 *start = hid->dev_rdesc;
__u8 *end = start + hid->dev_rsize;
static int (*dispatch_type[])(struct hid_parser *parser,
struct hid_item *item) = {
hid_scan_main,
hid_parser_global,
hid_parser_local,
hid_parser_reserved
};
parser = vzalloc(sizeof(struct hid_parser));
if (!parser)
return -ENOMEM;
parser->device = hid;
hid->group = HID_GROUP_GENERIC;
/*
* The parsing is simpler than the one in hid_open_report() as we should
* be robust against hid errors. Those errors will be raised by
* hid_open_report() anyway.
*/
while ((start = fetch_item(start, end, &item)) != NULL)
dispatch_type[item.type](parser, &item);
/*
* Handle special flags set during scanning.
*/
if ((parser->scan_flags & HID_SCAN_FLAG_MT_WIN_8) &&
(hid->group == HID_GROUP_MULTITOUCH))
hid->group = HID_GROUP_MULTITOUCH_WIN_8;
/*
* Vendor specific handlings
*/
switch (hid->vendor) {
case USB_VENDOR_ID_WACOM:
hid->group = HID_GROUP_WACOM;
break;
case USB_VENDOR_ID_SYNAPTICS:
if (hid->group == HID_GROUP_GENERIC)
if ((parser->scan_flags & HID_SCAN_FLAG_VENDOR_SPECIFIC)
&& (parser->scan_flags & HID_SCAN_FLAG_GD_POINTER))
/*
* hid-rmi should take care of them,
* not hid-generic
*/
2017-06-09 11:15:37 +00:00
hid->group = HID_GROUP_RMI;
break;
}
kfree(parser->collection_stack);
vfree(parser);
return 0;
}
/**
* hid_parse_report - parse device report
*
* @hid: hid device
* @start: report start
* @size: report size
*
* Allocate the device report as read by the bus driver. This function should
* only be called from parse() in ll drivers.
*/
int hid_parse_report(struct hid_device *hid, __u8 *start, unsigned size)
{
hid->dev_rdesc = kmemdup(start, size, GFP_KERNEL);
if (!hid->dev_rdesc)
return -ENOMEM;
hid->dev_rsize = size;
return 0;
}
EXPORT_SYMBOL_GPL(hid_parse_report);
static const char * const hid_report_names[] = {
"HID_INPUT_REPORT",
"HID_OUTPUT_REPORT",
"HID_FEATURE_REPORT",
};
/**
* hid_validate_values - validate existing device report's value indexes
*
* @hid: hid device
* @type: which report type to examine
* @id: which report ID to examine (0 for first)
* @field_index: which report field to examine
* @report_counts: expected number of values
*
* Validate the number of values in a given field of a given report, after
* parsing.
*/
struct hid_report *hid_validate_values(struct hid_device *hid,
unsigned int type, unsigned int id,
unsigned int field_index,
unsigned int report_counts)
{
struct hid_report *report;
if (type > HID_FEATURE_REPORT) {
hid_err(hid, "invalid HID report type %u\n", type);
return NULL;
}
if (id >= HID_MAX_IDS) {
hid_err(hid, "invalid HID report id %u\n", id);
return NULL;
}
/*
* Explicitly not using hid_get_report() here since it depends on
* ->numbered being checked, which may not always be the case when
* drivers go to access report values.
*/
if (id == 0) {
/*
* Validating on id 0 means we should examine the first
* report in the list.
*/
report = list_entry(
hid->report_enum[type].report_list.next,
struct hid_report, list);
} else {
report = hid->report_enum[type].report_id_hash[id];
}
if (!report) {
hid_err(hid, "missing %s %u\n", hid_report_names[type], id);
return NULL;
}
if (report->maxfield <= field_index) {
hid_err(hid, "not enough fields in %s %u\n",
hid_report_names[type], id);
return NULL;
}
if (report->field[field_index]->report_count < report_counts) {
hid_err(hid, "not enough values in %s %u field %u\n",
hid_report_names[type], id, field_index);
return NULL;
}
return report;
}
EXPORT_SYMBOL_GPL(hid_validate_values);
static int hid_calculate_multiplier(struct hid_device *hid,
struct hid_field *multiplier)
{
int m;
__s32 v = *multiplier->value;
__s32 lmin = multiplier->logical_minimum;
__s32 lmax = multiplier->logical_maximum;
__s32 pmin = multiplier->physical_minimum;
__s32 pmax = multiplier->physical_maximum;
/*
* "Because OS implementations will generally divide the control's
* reported count by the Effective Resolution Multiplier, designers
* should take care not to establish a potential Effective
* Resolution Multiplier of zero."
* HID Usage Table, v1.12, Section 4.3.1, p31
*/
if (lmax - lmin == 0)
return 1;
/*
* Handling the unit exponent is left as an exercise to whoever
* finds a device where that exponent is not 0.
*/
m = ((v - lmin)/(lmax - lmin) * (pmax - pmin) + pmin);
if (unlikely(multiplier->unit_exponent != 0)) {
hid_warn(hid,
"unsupported Resolution Multiplier unit exponent %d\n",
multiplier->unit_exponent);
}
/* There are no devices with an effective multiplier > 255 */
if (unlikely(m == 0 || m > 255 || m < -255)) {
hid_warn(hid, "unsupported Resolution Multiplier %d\n", m);
m = 1;
}
return m;
}
static void hid_apply_multiplier_to_field(struct hid_device *hid,
struct hid_field *field,
struct hid_collection *multiplier_collection,
int effective_multiplier)
{
struct hid_collection *collection;
struct hid_usage *usage;
int i;
/*
* If multiplier_collection is NULL, the multiplier applies
* to all fields in the report.
* Otherwise, it is the Logical Collection the multiplier applies to
* but our field may be in a subcollection of that collection.
*/
for (i = 0; i < field->maxusage; i++) {
usage = &field->usage[i];
collection = &hid->collection[usage->collection_index];
while (collection->parent_idx != -1 &&
collection != multiplier_collection)
collection = &hid->collection[collection->parent_idx];
if (collection->parent_idx != -1 ||
multiplier_collection == NULL)
usage->resolution_multiplier = effective_multiplier;
}
}
static void hid_apply_multiplier(struct hid_device *hid,
struct hid_field *multiplier)
{
struct hid_report_enum *rep_enum;
struct hid_report *rep;
struct hid_field *field;
struct hid_collection *multiplier_collection;
int effective_multiplier;
int i;
/*
* "The Resolution Multiplier control must be contained in the same
* Logical Collection as the control(s) to which it is to be applied.
* If no Resolution Multiplier is defined, then the Resolution
* Multiplier defaults to 1. If more than one control exists in a
* Logical Collection, the Resolution Multiplier is associated with
* all controls in the collection. If no Logical Collection is
* defined, the Resolution Multiplier is associated with all
* controls in the report."
* HID Usage Table, v1.12, Section 4.3.1, p30
*
* Thus, search from the current collection upwards until we find a
* logical collection. Then search all fields for that same parent
* collection. Those are the fields the multiplier applies to.
*
* If we have more than one multiplier, it will overwrite the
* applicable fields later.
*/
multiplier_collection = &hid->collection[multiplier->usage->collection_index];
while (multiplier_collection->parent_idx != -1 &&
multiplier_collection->type != HID_COLLECTION_LOGICAL)
multiplier_collection = &hid->collection[multiplier_collection->parent_idx];
effective_multiplier = hid_calculate_multiplier(hid, multiplier);
rep_enum = &hid->report_enum[HID_INPUT_REPORT];
list_for_each_entry(rep, &rep_enum->report_list, list) {
for (i = 0; i < rep->maxfield; i++) {
field = rep->field[i];
hid_apply_multiplier_to_field(hid, field,
multiplier_collection,
effective_multiplier);
}
}
}
/*
* hid_setup_resolution_multiplier - set up all resolution multipliers
*
* @device: hid device
*
* Search for all Resolution Multiplier Feature Reports and apply their
* value to all matching Input items. This only updates the internal struct
* fields.
*
* The Resolution Multiplier is applied by the hardware. If the multiplier
* is anything other than 1, the hardware will send pre-multiplied events
* so that the same physical interaction generates an accumulated
* accumulated_value = value * * multiplier
* This may be achieved by sending
* - "value * multiplier" for each event, or
* - "value" but "multiplier" times as frequently, or
* - a combination of the above
* The only guarantee is that the same physical interaction always generates
* an accumulated 'value * multiplier'.
*
* This function must be called before any event processing and after
* any SetRequest to the Resolution Multiplier.
*/
void hid_setup_resolution_multiplier(struct hid_device *hid)
{
struct hid_report_enum *rep_enum;
struct hid_report *rep;
struct hid_usage *usage;
int i, j;
rep_enum = &hid->report_enum[HID_FEATURE_REPORT];
list_for_each_entry(rep, &rep_enum->report_list, list) {
for (i = 0; i < rep->maxfield; i++) {
/* Ignore if report count is out of bounds. */
if (rep->field[i]->report_count < 1)
continue;
for (j = 0; j < rep->field[i]->maxusage; j++) {
usage = &rep->field[i]->usage[j];
if (usage->hid == HID_GD_RESOLUTION_MULTIPLIER)
hid_apply_multiplier(hid,
rep->field[i]);
}
}
}
}
EXPORT_SYMBOL_GPL(hid_setup_resolution_multiplier);
/**
* hid_open_report - open a driver-specific device report
*
* @device: hid device
*
* Parse a report description into a hid_device structure. Reports are
* enumerated, fields are attached to these reports.
* 0 returned on success, otherwise nonzero error value.
*
* This function (or the equivalent hid_parse() macro) should only be
* called from probe() in drivers, before starting the device.
*/
int hid_open_report(struct hid_device *device)
{
struct hid_parser *parser;
struct hid_item item;
unsigned int size;
__u8 *start;
__u8 *buf;
__u8 *end;
__u8 *next;
int ret;
static int (*dispatch_type[])(struct hid_parser *parser,
struct hid_item *item) = {
hid_parser_main,
hid_parser_global,
hid_parser_local,
hid_parser_reserved
};
if (WARN_ON(device->status & HID_STAT_PARSED))
return -EBUSY;
start = device->dev_rdesc;
if (WARN_ON(!start))
return -ENODEV;
size = device->dev_rsize;
buf = kmemdup(start, size, GFP_KERNEL);
if (buf == NULL)
return -ENOMEM;
if (device->driver->report_fixup)
start = device->driver->report_fixup(device, buf, &size);
else
start = buf;
start = kmemdup(start, size, GFP_KERNEL);
kfree(buf);
if (start == NULL)
return -ENOMEM;
device->rdesc = start;
device->rsize = size;
parser = vzalloc(sizeof(struct hid_parser));
if (!parser) {
ret = -ENOMEM;
goto alloc_err;
}
parser->device = device;
end = start + size;
device->collection = kcalloc(HID_DEFAULT_NUM_COLLECTIONS,
sizeof(struct hid_collection), GFP_KERNEL);
if (!device->collection) {
ret = -ENOMEM;
goto err;
}
device->collection_size = HID_DEFAULT_NUM_COLLECTIONS;
ret = -EINVAL;
while ((next = fetch_item(start, end, &item)) != NULL) {
start = next;
if (item.format != HID_ITEM_FORMAT_SHORT) {
hid_err(device, "unexpected long global item\n");
goto err;
}
if (dispatch_type[item.type](parser, &item)) {
hid_err(device, "item %u %u %u %u parsing failed\n",
item.format, (unsigned)item.size,
(unsigned)item.type, (unsigned)item.tag);
goto err;
}
if (start == end) {
if (parser->collection_stack_ptr) {
hid_err(device, "unbalanced collection at end of report description\n");
goto err;
}
if (parser->local.delimiter_depth) {
hid_err(device, "unbalanced delimiter at end of report description\n");
goto err;
}
/*
* fetch initial values in case the device's
* default multiplier isn't the recommended 1
*/
hid_setup_resolution_multiplier(device);
kfree(parser->collection_stack);
vfree(parser);
device->status |= HID_STAT_PARSED;
return 0;
}
}
hid_err(device, "item fetching failed at offset %u/%u\n",
size - (unsigned int)(end - start), size);
err:
kfree(parser->collection_stack);
alloc_err:
vfree(parser);
hid_close_report(device);
return ret;
}
EXPORT_SYMBOL_GPL(hid_open_report);
/*
* Convert a signed n-bit integer to signed 32-bit integer. Common
* cases are done through the compiler, the screwed things has to be
* done by hand.
*/
static s32 snto32(__u32 value, unsigned n)
{
if (!value || !n)
return 0;
switch (n) {
case 8: return ((__s8)value);
case 16: return ((__s16)value);
case 32: return ((__s32)value);
}
return value & (1 << (n - 1)) ? value | (~0U << n) : value;
}
s32 hid_snto32(__u32 value, unsigned n)
{
return snto32(value, n);
}
EXPORT_SYMBOL_GPL(hid_snto32);
/*
* Convert a signed 32-bit integer to a signed n-bit integer.
*/
static u32 s32ton(__s32 value, unsigned n)
{
s32 a = value >> (n - 1);
if (a && a != -1)
return value < 0 ? 1 << (n - 1) : (1 << (n - 1)) - 1;
return value & ((1 << n) - 1);
}
/*
* Extract/implement a data field from/to a little endian report (bit array).
*
* Code sort-of follows HID spec:
* http://www.usb.org/developers/hidpage/HID1_11.pdf
*
* While the USB HID spec allows unlimited length bit fields in "report
* descriptors", most devices never use more than 16 bits.
* One model of UPS is claimed to report "LINEV" as a 32-bit field.
* Search linux-kernel and linux-usb-devel archives for "hid-core extract".
*/
static u32 __extract(u8 *report, unsigned offset, int n)
{
unsigned int idx = offset / 8;
unsigned int bit_nr = 0;
unsigned int bit_shift = offset % 8;
int bits_to_copy = 8 - bit_shift;
u32 value = 0;
u32 mask = n < 32 ? (1U << n) - 1 : ~0U;
while (n > 0) {
value |= ((u32)report[idx] >> bit_shift) << bit_nr;
n -= bits_to_copy;
bit_nr += bits_to_copy;
bits_to_copy = 8;
bit_shift = 0;
idx++;
}
return value & mask;
}
u32 hid_field_extract(const struct hid_device *hid, u8 *report,
unsigned offset, unsigned n)
{
if (n > 32) {
hid_warn_once(hid, "%s() called with n (%d) > 32! (%s)\n",
__func__, n, current->comm);
n = 32;
}
return __extract(report, offset, n);
}
EXPORT_SYMBOL_GPL(hid_field_extract);
/*
* "implement" : set bits in a little endian bit stream.
* Same concepts as "extract" (see comments above).
* The data mangled in the bit stream remains in little endian
* order the whole time. It make more sense to talk about
* endianness of register values by considering a register
* a "cached" copy of the little endian bit stream.
*/
static void __implement(u8 *report, unsigned offset, int n, u32 value)
{
unsigned int idx = offset / 8;
unsigned int bit_shift = offset % 8;
int bits_to_set = 8 - bit_shift;
while (n - bits_to_set >= 0) {
report[idx] &= ~(0xff << bit_shift);
report[idx] |= value << bit_shift;
value >>= bits_to_set;
n -= bits_to_set;
bits_to_set = 8;
bit_shift = 0;
idx++;
}
/* last nibble */
if (n) {
u8 bit_mask = ((1U << n) - 1);
report[idx] &= ~(bit_mask << bit_shift);
report[idx] |= value << bit_shift;
}
}
static void implement(const struct hid_device *hid, u8 *report,
unsigned offset, unsigned n, u32 value)
{
if (unlikely(n > 32)) {
hid_warn(hid, "%s() called with n (%d) > 32! (%s)\n",
__func__, n, current->comm);
n = 32;
} else if (n < 32) {
u32 m = (1U << n) - 1;
if (unlikely(value > m)) {
hid_warn(hid,
"%s() called with too large value %d (n: %d)! (%s)\n",
__func__, value, n, current->comm);
WARN_ON(1);
value &= m;
}
}
__implement(report, offset, n, value);
}
/*
* Search an array for a value.
*/
static int search(__s32 *array, __s32 value, unsigned n)
{
while (n--) {
if (*array++ == value)
return 0;
}
return -1;
}
/**
* hid_match_report - check if driver's raw_event should be called
*
* @hid: hid device
* @report: hid report to match against
*
* compare hid->driver->report_table->report_type to report->type
*/
static int hid_match_report(struct hid_device *hid, struct hid_report *report)
{
const struct hid_report_id *id = hid->driver->report_table;
if (!id) /* NULL means all */
return 1;
for (; id->report_type != HID_TERMINATOR; id++)
if (id->report_type == HID_ANY_ID ||
id->report_type == report->type)
return 1;
return 0;
}
/**
* hid_match_usage - check if driver's event should be called
*
* @hid: hid device
* @usage: usage to match against
*
* compare hid->driver->usage_table->usage_{type,code} to
* usage->usage_{type,code}
*/
static int hid_match_usage(struct hid_device *hid, struct hid_usage *usage)
{
const struct hid_usage_id *id = hid->driver->usage_table;
if (!id) /* NULL means all */
return 1;
for (; id->usage_type != HID_ANY_ID - 1; id++)
if ((id->usage_hid == HID_ANY_ID ||
id->usage_hid == usage->hid) &&
(id->usage_type == HID_ANY_ID ||
id->usage_type == usage->type) &&
(id->usage_code == HID_ANY_ID ||
id->usage_code == usage->code))
return 1;
return 0;
}
static void hid_process_event(struct hid_device *hid, struct hid_field *field,
struct hid_usage *usage, __s32 value, int interrupt)
{
struct hid_driver *hdrv = hid->driver;
int ret;
if (!list_empty(&hid->debug_list))
hid_dump_input(hid, usage, value);
if (hdrv && hdrv->event && hid_match_usage(hid, usage)) {
ret = hdrv->event(hid, field, usage, value);
if (ret != 0) {
if (ret < 0)
hid_err(hid, "%s's event failed with %d\n",
hdrv->name, ret);
return;
}
}
if (hid->claimed & HID_CLAIMED_INPUT)
hidinput_hid_event(hid, field, usage, value);
if (hid->claimed & HID_CLAIMED_HIDDEV && interrupt && hid->hiddev_hid_event)
hid->hiddev_hid_event(hid, field, usage, value);
}
/*
* Analyse a received field, and fetch the data from it. The field
* content is stored for next report processing (we do differential
* reporting to the layer).
*/
static void hid_input_field(struct hid_device *hid, struct hid_field *field,
__u8 *data, int interrupt)
{
unsigned n;
unsigned count = field->report_count;
unsigned offset = field->report_offset;
unsigned size = field->report_size;
__s32 min = field->logical_minimum;
__s32 max = field->logical_maximum;
__s32 *value;
treewide: kmalloc() -> kmalloc_array() The kmalloc() function has a 2-factor argument form, kmalloc_array(). This patch replaces cases of: kmalloc(a * b, gfp) with: kmalloc_array(a * b, gfp) as well as handling cases of: kmalloc(a * b * c, gfp) with: kmalloc(array3_size(a, b, c), gfp) as it's slightly less ugly than: kmalloc_array(array_size(a, b), c, gfp) This does, however, attempt to ignore constant size factors like: kmalloc(4 * 1024, gfp) though any constants defined via macros get caught up in the conversion. Any factors with a sizeof() of "unsigned char", "char", and "u8" were dropped, since they're redundant. The tools/ directory was manually excluded, since it has its own implementation of kmalloc(). The Coccinelle script used for this was: // Fix redundant parens around sizeof(). @@ type TYPE; expression THING, E; @@ ( kmalloc( - (sizeof(TYPE)) * E + sizeof(TYPE) * E , ...) | kmalloc( - (sizeof(THING)) * E + sizeof(THING) * E , ...) ) // Drop single-byte sizes and redundant parens. @@ expression COUNT; typedef u8; typedef __u8; @@ ( kmalloc( - sizeof(u8) * (COUNT) + COUNT , ...) | kmalloc( - sizeof(__u8) * (COUNT) + COUNT , ...) | kmalloc( - sizeof(char) * (COUNT) + COUNT , ...) | kmalloc( - sizeof(unsigned char) * (COUNT) + COUNT , ...) | kmalloc( - sizeof(u8) * COUNT + COUNT , ...) | kmalloc( - sizeof(__u8) * COUNT + COUNT , ...) | kmalloc( - sizeof(char) * COUNT + COUNT , ...) | kmalloc( - sizeof(unsigned char) * COUNT + COUNT , ...) ) // 2-factor product with sizeof(type/expression) and identifier or constant. @@ type TYPE; expression THING; identifier COUNT_ID; constant COUNT_CONST; @@ ( - kmalloc + kmalloc_array ( - sizeof(TYPE) * (COUNT_ID) + COUNT_ID, sizeof(TYPE) , ...) | - kmalloc + kmalloc_array ( - sizeof(TYPE) * COUNT_ID + COUNT_ID, sizeof(TYPE) , ...) | - kmalloc + kmalloc_array ( - sizeof(TYPE) * (COUNT_CONST) + COUNT_CONST, sizeof(TYPE) , ...) | - kmalloc + kmalloc_array ( - sizeof(TYPE) * COUNT_CONST + COUNT_CONST, sizeof(TYPE) , ...) | - kmalloc + kmalloc_array ( - sizeof(THING) * (COUNT_ID) + COUNT_ID, sizeof(THING) , ...) | - kmalloc + kmalloc_array ( - sizeof(THING) * COUNT_ID + COUNT_ID, sizeof(THING) , ...) | - kmalloc + kmalloc_array ( - sizeof(THING) * (COUNT_CONST) + COUNT_CONST, sizeof(THING) , ...) | - kmalloc + kmalloc_array ( - sizeof(THING) * COUNT_CONST + COUNT_CONST, sizeof(THING) , ...) ) // 2-factor product, only identifiers. @@ identifier SIZE, COUNT; @@ - kmalloc + kmalloc_array ( - SIZE * COUNT + COUNT, SIZE , ...) // 3-factor product with 1 sizeof(type) or sizeof(expression), with // redundant parens removed. @@ expression THING; identifier STRIDE, COUNT; type TYPE; @@ ( kmalloc( - sizeof(TYPE) * (COUNT) * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kmalloc( - sizeof(TYPE) * (COUNT) * STRIDE + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kmalloc( - sizeof(TYPE) * COUNT * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kmalloc( - sizeof(TYPE) * COUNT * STRIDE + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kmalloc( - sizeof(THING) * (COUNT) * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kmalloc( - sizeof(THING) * (COUNT) * STRIDE + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kmalloc( - sizeof(THING) * COUNT * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kmalloc( - sizeof(THING) * COUNT * STRIDE + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) ) // 3-factor product with 2 sizeof(variable), with redundant parens removed. @@ expression THING1, THING2; identifier COUNT; type TYPE1, TYPE2; @@ ( kmalloc( - sizeof(TYPE1) * sizeof(TYPE2) * COUNT + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2)) , ...) | kmalloc( - sizeof(TYPE1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2)) , ...) | kmalloc( - sizeof(THING1) * sizeof(THING2) * COUNT + array3_size(COUNT, sizeof(THING1), sizeof(THING2)) , ...) | kmalloc( - sizeof(THING1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(THING1), sizeof(THING2)) , ...) | kmalloc( - sizeof(TYPE1) * sizeof(THING2) * COUNT + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2)) , ...) | kmalloc( - sizeof(TYPE1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2)) , ...) ) // 3-factor product, only identifiers, with redundant parens removed. @@ identifier STRIDE, SIZE, COUNT; @@ ( kmalloc( - (COUNT) * STRIDE * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - COUNT * (STRIDE) * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - COUNT * STRIDE * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - (COUNT) * (STRIDE) * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - COUNT * (STRIDE) * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - (COUNT) * STRIDE * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - (COUNT) * (STRIDE) * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - COUNT * STRIDE * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) ) // Any remaining multi-factor products, first at least 3-factor products, // when they're not all constants... @@ expression E1, E2, E3; constant C1, C2, C3; @@ ( kmalloc(C1 * C2 * C3, ...) | kmalloc( - (E1) * E2 * E3 + array3_size(E1, E2, E3) , ...) | kmalloc( - (E1) * (E2) * E3 + array3_size(E1, E2, E3) , ...) | kmalloc( - (E1) * (E2) * (E3) + array3_size(E1, E2, E3) , ...) | kmalloc( - E1 * E2 * E3 + array3_size(E1, E2, E3) , ...) ) // And then all remaining 2 factors products when they're not all constants, // keeping sizeof() as the second factor argument. @@ expression THING, E1, E2; type TYPE; constant C1, C2, C3; @@ ( kmalloc(sizeof(THING) * C2, ...) | kmalloc(sizeof(TYPE) * C2, ...) | kmalloc(C1 * C2 * C3, ...) | kmalloc(C1 * C2, ...) | - kmalloc + kmalloc_array ( - sizeof(TYPE) * (E2) + E2, sizeof(TYPE) , ...) | - kmalloc + kmalloc_array ( - sizeof(TYPE) * E2 + E2, sizeof(TYPE) , ...) | - kmalloc + kmalloc_array ( - sizeof(THING) * (E2) + E2, sizeof(THING) , ...) | - kmalloc + kmalloc_array ( - sizeof(THING) * E2 + E2, sizeof(THING) , ...) | - kmalloc + kmalloc_array ( - (E1) * E2 + E1, E2 , ...) | - kmalloc + kmalloc_array ( - (E1) * (E2) + E1, E2 , ...) | - kmalloc + kmalloc_array ( - E1 * E2 + E1, E2 , ...) ) Signed-off-by: Kees Cook <keescook@chromium.org>
2018-06-12 20:55:00 +00:00
value = kmalloc_array(count, sizeof(__s32), GFP_ATOMIC);
if (!value)
return;
for (n = 0; n < count; n++) {
value[n] = min < 0 ?
snto32(hid_field_extract(hid, data, offset + n * size,
size), size) :
hid_field_extract(hid, data, offset + n * size, size);
/* Ignore report if ErrorRollOver */
if (!(field->flags & HID_MAIN_ITEM_VARIABLE) &&
value[n] >= min && value[n] <= max &&
value[n] - min < field->maxusage &&
field->usage[value[n] - min].hid == HID_UP_KEYBOARD + 1)
goto exit;
}
for (n = 0; n < count; n++) {
if (HID_MAIN_ITEM_VARIABLE & field->flags) {
hid_process_event(hid, field, &field->usage[n], value[n], interrupt);
continue;
}
if (field->value[n] >= min && field->value[n] <= max
&& field->value[n] - min < field->maxusage
&& field->usage[field->value[n] - min].hid
&& search(value, field->value[n], count))
hid_process_event(hid, field, &field->usage[field->value[n] - min], 0, interrupt);
if (value[n] >= min && value[n] <= max
&& value[n] - min < field->maxusage
&& field->usage[value[n] - min].hid
&& search(field->value, value[n], count))
hid_process_event(hid, field, &field->usage[value[n] - min], 1, interrupt);
}
memcpy(field->value, value, count * sizeof(__s32));
exit:
kfree(value);
}
/*
* Output the field into the report.
*/
static void hid_output_field(const struct hid_device *hid,
struct hid_field *field, __u8 *data)
{
unsigned count = field->report_count;
unsigned offset = field->report_offset;
unsigned size = field->report_size;
unsigned n;
for (n = 0; n < count; n++) {
if (field->logical_minimum < 0) /* signed values */
implement(hid, data, offset + n * size, size,
s32ton(field->value[n], size));
else /* unsigned values */
implement(hid, data, offset + n * size, size,
field->value[n]);
}
}
/*
* Compute the size of a report.
*/
static size_t hid_compute_report_size(struct hid_report *report)
{
if (report->size)
return ((report->size - 1) >> 3) + 1;
return 0;
}
/*
HID: fix data access in implement() implement() is setting bytes in LE data stream. In case the data is not aligned to 64bits, it reads past the allocated buffer. It doesn't really change any value there (it's properly bitmasked), but in case that this read past the boundary hits a page boundary, pagefault happens when accessing 64bits of 'x' in implement(), and kernel oopses. This happens much more often when numbered reports are in use, as the initial 8bit skip in the buffer makes the whole process work on values which are not aligned to 64bits. This problem dates back to attempts in 2005 and 2006 to make implement() and extract() as generic as possible, and even back then the problem was realized by Adam Kroperlin, but falsely assumed to be impossible to cause any harm: http://www.mail-archive.com/linux-usb-devel@lists.sourceforge.net/msg47690.html I have made several attempts at fixing it "on the spot" directly in implement(), but the results were horrible; the special casing for processing last 64bit chunk and switching to different math makes it unreadable mess. I therefore took a path to allocate a few bytes more which will never make it into final report, but are there as a cushion for all the 64bit math operations happening in implement() and extract(). All callers of hid_output_report() are converted at the same time to allocate the buffer by newly introduced hid_alloc_report_buf() helper. Bruno noticed that the whole raw_size test can be dropped as well, as hid_alloc_report_buf() makes sure that the buffer is always of a proper size. Reviewed-by: Benjamin Tissoires <benjamin.tissoires@redhat.com> Acked-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2013-07-10 17:56:27 +00:00
* Create a report. 'data' has to be allocated using
* hid_alloc_report_buf() so that it has proper size.
*/
void hid_output_report(struct hid_report *report, __u8 *data)
{
unsigned n;
if (report->id > 0)
*data++ = report->id;
memset(data, 0, hid_compute_report_size(report));
for (n = 0; n < report->maxfield; n++)
hid_output_field(report->device, report->field[n], data);
}
EXPORT_SYMBOL_GPL(hid_output_report);
HID: fix data access in implement() implement() is setting bytes in LE data stream. In case the data is not aligned to 64bits, it reads past the allocated buffer. It doesn't really change any value there (it's properly bitmasked), but in case that this read past the boundary hits a page boundary, pagefault happens when accessing 64bits of 'x' in implement(), and kernel oopses. This happens much more often when numbered reports are in use, as the initial 8bit skip in the buffer makes the whole process work on values which are not aligned to 64bits. This problem dates back to attempts in 2005 and 2006 to make implement() and extract() as generic as possible, and even back then the problem was realized by Adam Kroperlin, but falsely assumed to be impossible to cause any harm: http://www.mail-archive.com/linux-usb-devel@lists.sourceforge.net/msg47690.html I have made several attempts at fixing it "on the spot" directly in implement(), but the results were horrible; the special casing for processing last 64bit chunk and switching to different math makes it unreadable mess. I therefore took a path to allocate a few bytes more which will never make it into final report, but are there as a cushion for all the 64bit math operations happening in implement() and extract(). All callers of hid_output_report() are converted at the same time to allocate the buffer by newly introduced hid_alloc_report_buf() helper. Bruno noticed that the whole raw_size test can be dropped as well, as hid_alloc_report_buf() makes sure that the buffer is always of a proper size. Reviewed-by: Benjamin Tissoires <benjamin.tissoires@redhat.com> Acked-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2013-07-10 17:56:27 +00:00
/*
* Allocator for buffer that is going to be passed to hid_output_report()
*/
u8 *hid_alloc_report_buf(struct hid_report *report, gfp_t flags)
{
/*
* 7 extra bytes are necessary to achieve proper functionality
* of implement() working on 8 byte chunks
*/
u32 len = hid_report_len(report) + 7;
HID: fix data access in implement() implement() is setting bytes in LE data stream. In case the data is not aligned to 64bits, it reads past the allocated buffer. It doesn't really change any value there (it's properly bitmasked), but in case that this read past the boundary hits a page boundary, pagefault happens when accessing 64bits of 'x' in implement(), and kernel oopses. This happens much more often when numbered reports are in use, as the initial 8bit skip in the buffer makes the whole process work on values which are not aligned to 64bits. This problem dates back to attempts in 2005 and 2006 to make implement() and extract() as generic as possible, and even back then the problem was realized by Adam Kroperlin, but falsely assumed to be impossible to cause any harm: http://www.mail-archive.com/linux-usb-devel@lists.sourceforge.net/msg47690.html I have made several attempts at fixing it "on the spot" directly in implement(), but the results were horrible; the special casing for processing last 64bit chunk and switching to different math makes it unreadable mess. I therefore took a path to allocate a few bytes more which will never make it into final report, but are there as a cushion for all the 64bit math operations happening in implement() and extract(). All callers of hid_output_report() are converted at the same time to allocate the buffer by newly introduced hid_alloc_report_buf() helper. Bruno noticed that the whole raw_size test can be dropped as well, as hid_alloc_report_buf() makes sure that the buffer is always of a proper size. Reviewed-by: Benjamin Tissoires <benjamin.tissoires@redhat.com> Acked-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2013-07-10 17:56:27 +00:00
return kmalloc(len, flags);
}
EXPORT_SYMBOL_GPL(hid_alloc_report_buf);
/*
* Set a field value. The report this field belongs to has to be
* created and transferred to the device, to set this value in the
* device.
*/
int hid_set_field(struct hid_field *field, unsigned offset, __s32 value)
{
unsigned size;
if (!field)
return -1;
size = field->report_size;
hid_dump_input(field->report->device, field->usage + offset, value);
if (offset >= field->report_count) {
hid_err(field->report->device, "offset (%d) exceeds report_count (%d)\n",
offset, field->report_count);
return -1;
}
if (field->logical_minimum < 0) {
if (value != snto32(s32ton(value, size), size)) {
hid_err(field->report->device, "value %d is out of range\n", value);
return -1;
}
}
field->value[offset] = value;
return 0;
}
EXPORT_SYMBOL_GPL(hid_set_field);
static struct hid_report *hid_get_report(struct hid_report_enum *report_enum,
const u8 *data)
{
struct hid_report *report;
unsigned int n = 0; /* Normally report number is 0 */
/* Device uses numbered reports, data[0] is report number */
if (report_enum->numbered)
n = *data;
report = report_enum->report_id_hash[n];
if (report == NULL)
dbg_hid("undefined report_id %u received\n", n);
return report;
}
/*
* Implement a generic .request() callback, using .raw_request()
* DO NOT USE in hid drivers directly, but through hid_hw_request instead.
*/
int __hid_request(struct hid_device *hid, struct hid_report *report,
int reqtype)
{
char *buf;
int ret;
u32 len;
buf = hid_alloc_report_buf(report, GFP_KERNEL);
if (!buf)
return -ENOMEM;
len = hid_report_len(report);
if (reqtype == HID_REQ_SET_REPORT)
hid_output_report(report, buf);
ret = hid->ll_driver->raw_request(hid, report->id, buf, len,
report->type, reqtype);
if (ret < 0) {
dbg_hid("unable to complete request: %d\n", ret);
goto out;
}
if (reqtype == HID_REQ_GET_REPORT)
hid_input_report(hid, report->type, buf, ret, 0);
ret = 0;
out:
kfree(buf);
return ret;
}
EXPORT_SYMBOL_GPL(__hid_request);
int hid_report_raw_event(struct hid_device *hid, int type, u8 *data, u32 size,
int interrupt)
{
struct hid_report_enum *report_enum = hid->report_enum + type;
struct hid_report *report;
struct hid_driver *hdrv;
unsigned int a;
u32 rsize, csize = size;
u8 *cdata = data;
int ret = 0;
report = hid_get_report(report_enum, data);
if (!report)
goto out;
if (report_enum->numbered) {
cdata++;
csize--;
}
rsize = hid_compute_report_size(report);
if (report_enum->numbered && rsize >= HID_MAX_BUFFER_SIZE)
rsize = HID_MAX_BUFFER_SIZE - 1;
else if (rsize > HID_MAX_BUFFER_SIZE)
rsize = HID_MAX_BUFFER_SIZE;
if (csize < rsize) {
dbg_hid("report %d is too short, (%d < %d)\n", report->id,
csize, rsize);
memset(cdata + csize, 0, rsize - csize);
}
if ((hid->claimed & HID_CLAIMED_HIDDEV) && hid->hiddev_report_event)
hid->hiddev_report_event(hid, report);
if (hid->claimed & HID_CLAIMED_HIDRAW) {
ret = hidraw_report_event(hid, data, size);
if (ret)
goto out;
}
if (hid->claimed != HID_CLAIMED_HIDRAW && report->maxfield) {
for (a = 0; a < report->maxfield; a++)
hid_input_field(hid, report->field[a], cdata, interrupt);
hdrv = hid->driver;
if (hdrv && hdrv->report)
hdrv->report(hid, report);
}
if (hid->claimed & HID_CLAIMED_INPUT)
hidinput_report_event(hid, report);
out:
return ret;
}
EXPORT_SYMBOL_GPL(hid_report_raw_event);
/**
* hid_input_report - report data from lower layer (usb, bt...)
*
* @hid: hid device
* @type: HID report type (HID_*_REPORT)
* @data: report contents
* @size: size of data parameter
* @interrupt: distinguish between interrupt and control transfers
*
* This is data entry for lower layers.
*/
int hid_input_report(struct hid_device *hid, int type, u8 *data, u32 size, int interrupt)
{
struct hid_report_enum *report_enum;
struct hid_driver *hdrv;
struct hid_report *report;
int ret = 0;
HID: Fix race condition between driver core and ll-driver HID low level drivers register new devices with the HID core which then adds the devices to the HID bus. The HID bus normally immediately probes an appropriate driver which then handles HID input for this device. The ll driver now uses the hid_input_report() function to report input events for a specific device. However, if the HID bus unloads the driver at the same time (for instance via a call to /sys/bus/hid/devices/<dev>/unbind) then the hdev->driver pointer may be used by hid_input_report() and hid_device_remove() at the same time which may cause hdev->driver to point to invalid memory. This fix adds a semaphore to every hid device which protects hdev->driver from asynchronous access. This semaphore is locked during driver *_probe and *_remove and also inside hid_input_report(). The *_probe and *_remove functions may sleep so the semaphore is good here, however, hid_input_report() is in atomic context and hence only uses down_trylock(). If it cannot acquire the lock it simply drops the input package. The low-level drivers report input events synchronously so hid_input_report() should never be entered twice at the same time on the same device. Hence, the lock should always be available. But if the driver is currently probed/removed then the lock is not available and dropping the package should be safe because this is what would have happened if the package arrived some milliseconds earlier/later. This also fixes another race condition while probing drivers: First the *_probe function of the driver is called and only if that succeeds, the related input device of hidinput is registered. If the low level driver reports input events after the *_probe function returned but before the input device is registered, then a NULL pointer dereference will occur. (Equivalently on driver remove function). This is not possible anymore, since the semaphore lock drops all incoming packages until the driver/device is fully initialized. Signed-off-by: David Herrmann <dh.herrmann@googlemail.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2011-08-10 12:02:07 +00:00
if (!hid)
return -ENODEV;
HID: Fix race condition between driver core and ll-driver HID low level drivers register new devices with the HID core which then adds the devices to the HID bus. The HID bus normally immediately probes an appropriate driver which then handles HID input for this device. The ll driver now uses the hid_input_report() function to report input events for a specific device. However, if the HID bus unloads the driver at the same time (for instance via a call to /sys/bus/hid/devices/<dev>/unbind) then the hdev->driver pointer may be used by hid_input_report() and hid_device_remove() at the same time which may cause hdev->driver to point to invalid memory. This fix adds a semaphore to every hid device which protects hdev->driver from asynchronous access. This semaphore is locked during driver *_probe and *_remove and also inside hid_input_report(). The *_probe and *_remove functions may sleep so the semaphore is good here, however, hid_input_report() is in atomic context and hence only uses down_trylock(). If it cannot acquire the lock it simply drops the input package. The low-level drivers report input events synchronously so hid_input_report() should never be entered twice at the same time on the same device. Hence, the lock should always be available. But if the driver is currently probed/removed then the lock is not available and dropping the package should be safe because this is what would have happened if the package arrived some milliseconds earlier/later. This also fixes another race condition while probing drivers: First the *_probe function of the driver is called and only if that succeeds, the related input device of hidinput is registered. If the low level driver reports input events after the *_probe function returned but before the input device is registered, then a NULL pointer dereference will occur. (Equivalently on driver remove function). This is not possible anymore, since the semaphore lock drops all incoming packages until the driver/device is fully initialized. Signed-off-by: David Herrmann <dh.herrmann@googlemail.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2011-08-10 12:02:07 +00:00
HID: Separate struct hid_device's driver_lock into two locks. This patch separates struct hid_device's driver_lock into two. The goal is to allow hid device drivers to receive input during their probe() or remove() function calls. This is necessary because some drivers need to communicate with the device to determine parameters needed during probe (e.g., size of a multi-touch surface), and if possible, may perfer to communicate with a device on host-initiated disconnect (e.g., to put it into a low-power state). Historically, three functions used driver_lock: - hid_device_probe: blocks to acquire lock - hid_device_remove: blocks to acquire lock - hid_input_report: if locked returns -EBUSY, else acquires lock This patch adds another lock (driver_input_lock) which is used to block input from occurring. The lock behavior is now: - hid_device_probe: blocks to acq. driver_lock, then driver_input_lock - hid_device_remove: blocks to acq. driver_lock, then driver_input_lock - hid_input_report: if driver_input_lock locked returns -EBUSY, else acquires driver_input_lock This patch also adds two helper functions to be called during probe() or remove(): hid_device_io_start() and hid_device_io_stop(). These functions lock and unlock, respectively, driver_input_lock; they also make a note of whether they did so that hid-core knows if a driver has changed the lock state. This patch results in no behavior change for existing devices and drivers. However, during a probe() or remove() function call in a driver, that driver may now selectively call hid_device_io_start() to let input events come through, then optionally call hid_device_io_stop() to stop them. Signed-off-by: Andrew de los Reyes <adlr@chromium.org> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2013-02-18 17:20:21 +00:00
if (down_trylock(&hid->driver_input_lock))
HID: Fix race condition between driver core and ll-driver HID low level drivers register new devices with the HID core which then adds the devices to the HID bus. The HID bus normally immediately probes an appropriate driver which then handles HID input for this device. The ll driver now uses the hid_input_report() function to report input events for a specific device. However, if the HID bus unloads the driver at the same time (for instance via a call to /sys/bus/hid/devices/<dev>/unbind) then the hdev->driver pointer may be used by hid_input_report() and hid_device_remove() at the same time which may cause hdev->driver to point to invalid memory. This fix adds a semaphore to every hid device which protects hdev->driver from asynchronous access. This semaphore is locked during driver *_probe and *_remove and also inside hid_input_report(). The *_probe and *_remove functions may sleep so the semaphore is good here, however, hid_input_report() is in atomic context and hence only uses down_trylock(). If it cannot acquire the lock it simply drops the input package. The low-level drivers report input events synchronously so hid_input_report() should never be entered twice at the same time on the same device. Hence, the lock should always be available. But if the driver is currently probed/removed then the lock is not available and dropping the package should be safe because this is what would have happened if the package arrived some milliseconds earlier/later. This also fixes another race condition while probing drivers: First the *_probe function of the driver is called and only if that succeeds, the related input device of hidinput is registered. If the low level driver reports input events after the *_probe function returned but before the input device is registered, then a NULL pointer dereference will occur. (Equivalently on driver remove function). This is not possible anymore, since the semaphore lock drops all incoming packages until the driver/device is fully initialized. Signed-off-by: David Herrmann <dh.herrmann@googlemail.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2011-08-10 12:02:07 +00:00
return -EBUSY;
if (!hid->driver) {
ret = -ENODEV;
goto unlock;
}
report_enum = hid->report_enum + type;
hdrv = hid->driver;
if (!size) {
dbg_hid("empty report\n");
HID: Fix race condition between driver core and ll-driver HID low level drivers register new devices with the HID core which then adds the devices to the HID bus. The HID bus normally immediately probes an appropriate driver which then handles HID input for this device. The ll driver now uses the hid_input_report() function to report input events for a specific device. However, if the HID bus unloads the driver at the same time (for instance via a call to /sys/bus/hid/devices/<dev>/unbind) then the hdev->driver pointer may be used by hid_input_report() and hid_device_remove() at the same time which may cause hdev->driver to point to invalid memory. This fix adds a semaphore to every hid device which protects hdev->driver from asynchronous access. This semaphore is locked during driver *_probe and *_remove and also inside hid_input_report(). The *_probe and *_remove functions may sleep so the semaphore is good here, however, hid_input_report() is in atomic context and hence only uses down_trylock(). If it cannot acquire the lock it simply drops the input package. The low-level drivers report input events synchronously so hid_input_report() should never be entered twice at the same time on the same device. Hence, the lock should always be available. But if the driver is currently probed/removed then the lock is not available and dropping the package should be safe because this is what would have happened if the package arrived some milliseconds earlier/later. This also fixes another race condition while probing drivers: First the *_probe function of the driver is called and only if that succeeds, the related input device of hidinput is registered. If the low level driver reports input events after the *_probe function returned but before the input device is registered, then a NULL pointer dereference will occur. (Equivalently on driver remove function). This is not possible anymore, since the semaphore lock drops all incoming packages until the driver/device is fully initialized. Signed-off-by: David Herrmann <dh.herrmann@googlemail.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2011-08-10 12:02:07 +00:00
ret = -1;
goto unlock;
}
/* Avoid unnecessary overhead if debugfs is disabled */
if (!list_empty(&hid->debug_list))
hid_dump_report(hid, type, data, size);
report = hid_get_report(report_enum, data);
HID: Fix race condition between driver core and ll-driver HID low level drivers register new devices with the HID core which then adds the devices to the HID bus. The HID bus normally immediately probes an appropriate driver which then handles HID input for this device. The ll driver now uses the hid_input_report() function to report input events for a specific device. However, if the HID bus unloads the driver at the same time (for instance via a call to /sys/bus/hid/devices/<dev>/unbind) then the hdev->driver pointer may be used by hid_input_report() and hid_device_remove() at the same time which may cause hdev->driver to point to invalid memory. This fix adds a semaphore to every hid device which protects hdev->driver from asynchronous access. This semaphore is locked during driver *_probe and *_remove and also inside hid_input_report(). The *_probe and *_remove functions may sleep so the semaphore is good here, however, hid_input_report() is in atomic context and hence only uses down_trylock(). If it cannot acquire the lock it simply drops the input package. The low-level drivers report input events synchronously so hid_input_report() should never be entered twice at the same time on the same device. Hence, the lock should always be available. But if the driver is currently probed/removed then the lock is not available and dropping the package should be safe because this is what would have happened if the package arrived some milliseconds earlier/later. This also fixes another race condition while probing drivers: First the *_probe function of the driver is called and only if that succeeds, the related input device of hidinput is registered. If the low level driver reports input events after the *_probe function returned but before the input device is registered, then a NULL pointer dereference will occur. (Equivalently on driver remove function). This is not possible anymore, since the semaphore lock drops all incoming packages until the driver/device is fully initialized. Signed-off-by: David Herrmann <dh.herrmann@googlemail.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2011-08-10 12:02:07 +00:00
if (!report) {
ret = -1;
goto unlock;
}
if (hdrv && hdrv->raw_event && hid_match_report(hid, report)) {
ret = hdrv->raw_event(hid, report, data, size);
if (ret < 0)
HID: Fix race condition between driver core and ll-driver HID low level drivers register new devices with the HID core which then adds the devices to the HID bus. The HID bus normally immediately probes an appropriate driver which then handles HID input for this device. The ll driver now uses the hid_input_report() function to report input events for a specific device. However, if the HID bus unloads the driver at the same time (for instance via a call to /sys/bus/hid/devices/<dev>/unbind) then the hdev->driver pointer may be used by hid_input_report() and hid_device_remove() at the same time which may cause hdev->driver to point to invalid memory. This fix adds a semaphore to every hid device which protects hdev->driver from asynchronous access. This semaphore is locked during driver *_probe and *_remove and also inside hid_input_report(). The *_probe and *_remove functions may sleep so the semaphore is good here, however, hid_input_report() is in atomic context and hence only uses down_trylock(). If it cannot acquire the lock it simply drops the input package. The low-level drivers report input events synchronously so hid_input_report() should never be entered twice at the same time on the same device. Hence, the lock should always be available. But if the driver is currently probed/removed then the lock is not available and dropping the package should be safe because this is what would have happened if the package arrived some milliseconds earlier/later. This also fixes another race condition while probing drivers: First the *_probe function of the driver is called and only if that succeeds, the related input device of hidinput is registered. If the low level driver reports input events after the *_probe function returned but before the input device is registered, then a NULL pointer dereference will occur. (Equivalently on driver remove function). This is not possible anymore, since the semaphore lock drops all incoming packages until the driver/device is fully initialized. Signed-off-by: David Herrmann <dh.herrmann@googlemail.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2011-08-10 12:02:07 +00:00
goto unlock;
}
ret = hid_report_raw_event(hid, type, data, size, interrupt);
HID: Fix race condition between driver core and ll-driver HID low level drivers register new devices with the HID core which then adds the devices to the HID bus. The HID bus normally immediately probes an appropriate driver which then handles HID input for this device. The ll driver now uses the hid_input_report() function to report input events for a specific device. However, if the HID bus unloads the driver at the same time (for instance via a call to /sys/bus/hid/devices/<dev>/unbind) then the hdev->driver pointer may be used by hid_input_report() and hid_device_remove() at the same time which may cause hdev->driver to point to invalid memory. This fix adds a semaphore to every hid device which protects hdev->driver from asynchronous access. This semaphore is locked during driver *_probe and *_remove and also inside hid_input_report(). The *_probe and *_remove functions may sleep so the semaphore is good here, however, hid_input_report() is in atomic context and hence only uses down_trylock(). If it cannot acquire the lock it simply drops the input package. The low-level drivers report input events synchronously so hid_input_report() should never be entered twice at the same time on the same device. Hence, the lock should always be available. But if the driver is currently probed/removed then the lock is not available and dropping the package should be safe because this is what would have happened if the package arrived some milliseconds earlier/later. This also fixes another race condition while probing drivers: First the *_probe function of the driver is called and only if that succeeds, the related input device of hidinput is registered. If the low level driver reports input events after the *_probe function returned but before the input device is registered, then a NULL pointer dereference will occur. (Equivalently on driver remove function). This is not possible anymore, since the semaphore lock drops all incoming packages until the driver/device is fully initialized. Signed-off-by: David Herrmann <dh.herrmann@googlemail.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2011-08-10 12:02:07 +00:00
unlock:
HID: Separate struct hid_device's driver_lock into two locks. This patch separates struct hid_device's driver_lock into two. The goal is to allow hid device drivers to receive input during their probe() or remove() function calls. This is necessary because some drivers need to communicate with the device to determine parameters needed during probe (e.g., size of a multi-touch surface), and if possible, may perfer to communicate with a device on host-initiated disconnect (e.g., to put it into a low-power state). Historically, three functions used driver_lock: - hid_device_probe: blocks to acquire lock - hid_device_remove: blocks to acquire lock - hid_input_report: if locked returns -EBUSY, else acquires lock This patch adds another lock (driver_input_lock) which is used to block input from occurring. The lock behavior is now: - hid_device_probe: blocks to acq. driver_lock, then driver_input_lock - hid_device_remove: blocks to acq. driver_lock, then driver_input_lock - hid_input_report: if driver_input_lock locked returns -EBUSY, else acquires driver_input_lock This patch also adds two helper functions to be called during probe() or remove(): hid_device_io_start() and hid_device_io_stop(). These functions lock and unlock, respectively, driver_input_lock; they also make a note of whether they did so that hid-core knows if a driver has changed the lock state. This patch results in no behavior change for existing devices and drivers. However, during a probe() or remove() function call in a driver, that driver may now selectively call hid_device_io_start() to let input events come through, then optionally call hid_device_io_stop() to stop them. Signed-off-by: Andrew de los Reyes <adlr@chromium.org> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2013-02-18 17:20:21 +00:00
up(&hid->driver_input_lock);
return ret;
}
EXPORT_SYMBOL_GPL(hid_input_report);
bool hid_match_one_id(const struct hid_device *hdev,
const struct hid_device_id *id)
{
return (id->bus == HID_BUS_ANY || id->bus == hdev->bus) &&
(id->group == HID_GROUP_ANY || id->group == hdev->group) &&
(id->vendor == HID_ANY_ID || id->vendor == hdev->vendor) &&
(id->product == HID_ANY_ID || id->product == hdev->product);
}
const struct hid_device_id *hid_match_id(const struct hid_device *hdev,
const struct hid_device_id *id)
{
for (; id->bus; id++)
if (hid_match_one_id(hdev, id))
return id;
return NULL;
}
static const struct hid_device_id hid_hiddev_list[] = {
{ HID_USB_DEVICE(USB_VENDOR_ID_MGE, USB_DEVICE_ID_MGE_UPS) },
{ HID_USB_DEVICE(USB_VENDOR_ID_MGE, USB_DEVICE_ID_MGE_UPS1) },
{ }
};
static bool hid_hiddev(struct hid_device *hdev)
{
return !!hid_match_id(hdev, hid_hiddev_list);
}
static ssize_t
read_report_descriptor(struct file *filp, struct kobject *kobj,
struct bin_attribute *attr,
char *buf, loff_t off, size_t count)
{
struct device *dev = kobj_to_dev(kobj);
struct hid_device *hdev = to_hid_device(dev);
if (off >= hdev->rsize)
return 0;
if (off + count > hdev->rsize)
count = hdev->rsize - off;
memcpy(buf, hdev->rdesc + off, count);
return count;
}
static ssize_t
show_country(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct hid_device *hdev = to_hid_device(dev);
return sprintf(buf, "%02x\n", hdev->country & 0xff);
}
static struct bin_attribute dev_bin_attr_report_desc = {
.attr = { .name = "report_descriptor", .mode = 0444 },
.read = read_report_descriptor,
.size = HID_MAX_DESCRIPTOR_SIZE,
};
static const struct device_attribute dev_attr_country = {
.attr = { .name = "country", .mode = 0444 },
.show = show_country,
};
int hid_connect(struct hid_device *hdev, unsigned int connect_mask)
{
static const char *types[] = { "Device", "Pointer", "Mouse", "Device",
"Joystick", "Gamepad", "Keyboard", "Keypad",
"Multi-Axis Controller"
};
const char *type, *bus;
char buf[64] = "";
unsigned int i;
int len;
int ret;
if (hdev->quirks & HID_QUIRK_HIDDEV_FORCE)
connect_mask |= (HID_CONNECT_HIDDEV_FORCE | HID_CONNECT_HIDDEV);
if (hdev->quirks & HID_QUIRK_HIDINPUT_FORCE)
connect_mask |= HID_CONNECT_HIDINPUT_FORCE;
if (hdev->bus != BUS_USB)
connect_mask &= ~HID_CONNECT_HIDDEV;
if (hid_hiddev(hdev))
connect_mask |= HID_CONNECT_HIDDEV_FORCE;
if ((connect_mask & HID_CONNECT_HIDINPUT) && !hidinput_connect(hdev,
connect_mask & HID_CONNECT_HIDINPUT_FORCE))
hdev->claimed |= HID_CLAIMED_INPUT;
if ((connect_mask & HID_CONNECT_HIDDEV) && hdev->hiddev_connect &&
!hdev->hiddev_connect(hdev,
connect_mask & HID_CONNECT_HIDDEV_FORCE))
hdev->claimed |= HID_CLAIMED_HIDDEV;
if ((connect_mask & HID_CONNECT_HIDRAW) && !hidraw_connect(hdev))
hdev->claimed |= HID_CLAIMED_HIDRAW;
if (connect_mask & HID_CONNECT_DRIVER)
hdev->claimed |= HID_CLAIMED_DRIVER;
/* Drivers with the ->raw_event callback set are not required to connect
* to any other listener. */
if (!hdev->claimed && !hdev->driver->raw_event) {
hid_err(hdev, "device has no listeners, quitting\n");
return -ENODEV;
}
if ((hdev->claimed & HID_CLAIMED_INPUT) &&
(connect_mask & HID_CONNECT_FF) && hdev->ff_init)
hdev->ff_init(hdev);
len = 0;
if (hdev->claimed & HID_CLAIMED_INPUT)
len += sprintf(buf + len, "input");
if (hdev->claimed & HID_CLAIMED_HIDDEV)
len += sprintf(buf + len, "%shiddev%d", len ? "," : "",
((struct hiddev *)hdev->hiddev)->minor);
if (hdev->claimed & HID_CLAIMED_HIDRAW)
len += sprintf(buf + len, "%shidraw%d", len ? "," : "",
((struct hidraw *)hdev->hidraw)->minor);
type = "Device";
for (i = 0; i < hdev->maxcollection; i++) {
struct hid_collection *col = &hdev->collection[i];
if (col->type == HID_COLLECTION_APPLICATION &&
(col->usage & HID_USAGE_PAGE) == HID_UP_GENDESK &&
(col->usage & 0xffff) < ARRAY_SIZE(types)) {
type = types[col->usage & 0xffff];
break;
}
}
switch (hdev->bus) {
case BUS_USB:
bus = "USB";
break;
case BUS_BLUETOOTH:
bus = "BLUETOOTH";
break;
case BUS_I2C:
bus = "I2C";
break;
case BUS_VIRTUAL:
bus = "VIRTUAL";
break;
default:
bus = "<UNKNOWN>";
}
ret = device_create_file(&hdev->dev, &dev_attr_country);
if (ret)
hid_warn(hdev,
"can't create sysfs country code attribute err: %d\n", ret);
hid_info(hdev, "%s: %s HID v%x.%02x %s [%s] on %s\n",
buf, bus, hdev->version >> 8, hdev->version & 0xff,
type, hdev->name, hdev->phys);
return 0;
}
EXPORT_SYMBOL_GPL(hid_connect);
void hid_disconnect(struct hid_device *hdev)
{
device_remove_file(&hdev->dev, &dev_attr_country);
if (hdev->claimed & HID_CLAIMED_INPUT)
hidinput_disconnect(hdev);
if (hdev->claimed & HID_CLAIMED_HIDDEV)
hdev->hiddev_disconnect(hdev);
if (hdev->claimed & HID_CLAIMED_HIDRAW)
hidraw_disconnect(hdev);
hdev->claimed = 0;
}
EXPORT_SYMBOL_GPL(hid_disconnect);
/**
* hid_hw_start - start underlying HW
* @hdev: hid device
* @connect_mask: which outputs to connect, see HID_CONNECT_*
*
* Call this in probe function *after* hid_parse. This will setup HW
* buffers and start the device (if not defeirred to device open).
* hid_hw_stop must be called if this was successful.
*/
int hid_hw_start(struct hid_device *hdev, unsigned int connect_mask)
{
int error;
error = hdev->ll_driver->start(hdev);
if (error)
return error;
if (connect_mask) {
error = hid_connect(hdev, connect_mask);
if (error) {
hdev->ll_driver->stop(hdev);
return error;
}
}
return 0;
}
EXPORT_SYMBOL_GPL(hid_hw_start);
/**
* hid_hw_stop - stop underlying HW
* @hdev: hid device
*
* This is usually called from remove function or from probe when something
* failed and hid_hw_start was called already.
*/
void hid_hw_stop(struct hid_device *hdev)
{
hid_disconnect(hdev);
hdev->ll_driver->stop(hdev);
}
EXPORT_SYMBOL_GPL(hid_hw_stop);
/**
* hid_hw_open - signal underlying HW to start delivering events
* @hdev: hid device
*
* Tell underlying HW to start delivering events from the device.
* This function should be called sometime after successful call
* to hid_hw_start().
*/
int hid_hw_open(struct hid_device *hdev)
{
int ret;
ret = mutex_lock_killable(&hdev->ll_open_lock);
if (ret)
return ret;
if (!hdev->ll_open_count++) {
ret = hdev->ll_driver->open(hdev);
if (ret)
hdev->ll_open_count--;
}
mutex_unlock(&hdev->ll_open_lock);
return ret;
}
EXPORT_SYMBOL_GPL(hid_hw_open);
/**
* hid_hw_close - signal underlaying HW to stop delivering events
*
* @hdev: hid device
*
* This function indicates that we are not interested in the events
* from this device anymore. Delivery of events may or may not stop,
* depending on the number of users still outstanding.
*/
void hid_hw_close(struct hid_device *hdev)
{
mutex_lock(&hdev->ll_open_lock);
if (!--hdev->ll_open_count)
hdev->ll_driver->close(hdev);
mutex_unlock(&hdev->ll_open_lock);
}
EXPORT_SYMBOL_GPL(hid_hw_close);
/**
* hid_hw_request - send report request to device
*
* @hdev: hid device
* @report: report to send
* @reqtype: hid request type
*/
void hid_hw_request(struct hid_device *hdev,
struct hid_report *report, int reqtype)
{
if (hdev->ll_driver->request)
return hdev->ll_driver->request(hdev, report, reqtype);
__hid_request(hdev, report, reqtype);
}
EXPORT_SYMBOL_GPL(hid_hw_request);
/**
* hid_hw_raw_request - send report request to device
*
* @hdev: hid device
* @reportnum: report ID
* @buf: in/out data to transfer
* @len: length of buf
* @rtype: HID report type
* @reqtype: HID_REQ_GET_REPORT or HID_REQ_SET_REPORT
*
* Return: count of data transferred, negative if error
*
* Same behavior as hid_hw_request, but with raw buffers instead.
*/
int hid_hw_raw_request(struct hid_device *hdev,
unsigned char reportnum, __u8 *buf,
size_t len, unsigned char rtype, int reqtype)
{
if (len < 1 || len > HID_MAX_BUFFER_SIZE || !buf)
return -EINVAL;
return hdev->ll_driver->raw_request(hdev, reportnum, buf, len,
rtype, reqtype);
}
EXPORT_SYMBOL_GPL(hid_hw_raw_request);
/**
* hid_hw_output_report - send output report to device
*
* @hdev: hid device
* @buf: raw data to transfer
* @len: length of buf
*
* Return: count of data transferred, negative if error
*/
int hid_hw_output_report(struct hid_device *hdev, __u8 *buf, size_t len)
{
if (len < 1 || len > HID_MAX_BUFFER_SIZE || !buf)
return -EINVAL;
if (hdev->ll_driver->output_report)
return hdev->ll_driver->output_report(hdev, buf, len);
return -ENOSYS;
}
EXPORT_SYMBOL_GPL(hid_hw_output_report);
#ifdef CONFIG_PM
int hid_driver_suspend(struct hid_device *hdev, pm_message_t state)
{
if (hdev->driver && hdev->driver->suspend)
return hdev->driver->suspend(hdev, state);
return 0;
}
EXPORT_SYMBOL_GPL(hid_driver_suspend);
int hid_driver_reset_resume(struct hid_device *hdev)
{
if (hdev->driver && hdev->driver->reset_resume)
return hdev->driver->reset_resume(hdev);
return 0;
}
EXPORT_SYMBOL_GPL(hid_driver_reset_resume);
int hid_driver_resume(struct hid_device *hdev)
{
if (hdev->driver && hdev->driver->resume)
return hdev->driver->resume(hdev);
return 0;
}
EXPORT_SYMBOL_GPL(hid_driver_resume);
#endif /* CONFIG_PM */
struct hid_dynid {
struct list_head list;
struct hid_device_id id;
};
/**
* new_id_store - add a new HID device ID to this driver and re-probe devices
* @drv: target device driver
* @buf: buffer for scanning device ID data
* @count: input size
*
* Adds a new dynamic hid device ID to this driver,
* and causes the driver to probe for all devices again.
*/
static ssize_t new_id_store(struct device_driver *drv, const char *buf,
size_t count)
{
struct hid_driver *hdrv = to_hid_driver(drv);
struct hid_dynid *dynid;
__u32 bus, vendor, product;
unsigned long driver_data = 0;
int ret;
ret = sscanf(buf, "%x %x %x %lx",
&bus, &vendor, &product, &driver_data);
if (ret < 3)
return -EINVAL;
dynid = kzalloc(sizeof(*dynid), GFP_KERNEL);
if (!dynid)
return -ENOMEM;
dynid->id.bus = bus;
dynid->id.group = HID_GROUP_ANY;
dynid->id.vendor = vendor;
dynid->id.product = product;
dynid->id.driver_data = driver_data;
spin_lock(&hdrv->dyn_lock);
list_add_tail(&dynid->list, &hdrv->dyn_list);
spin_unlock(&hdrv->dyn_lock);
ret = driver_attach(&hdrv->driver);
return ret ? : count;
}
static DRIVER_ATTR_WO(new_id);
static struct attribute *hid_drv_attrs[] = {
&driver_attr_new_id.attr,
NULL,
};
ATTRIBUTE_GROUPS(hid_drv);
static void hid_free_dynids(struct hid_driver *hdrv)
{
struct hid_dynid *dynid, *n;
spin_lock(&hdrv->dyn_lock);
list_for_each_entry_safe(dynid, n, &hdrv->dyn_list, list) {
list_del(&dynid->list);
kfree(dynid);
}
spin_unlock(&hdrv->dyn_lock);
}
const struct hid_device_id *hid_match_device(struct hid_device *hdev,
struct hid_driver *hdrv)
{
struct hid_dynid *dynid;
spin_lock(&hdrv->dyn_lock);
list_for_each_entry(dynid, &hdrv->dyn_list, list) {
if (hid_match_one_id(hdev, &dynid->id)) {
spin_unlock(&hdrv->dyn_lock);
return &dynid->id;
}
}
spin_unlock(&hdrv->dyn_lock);
return hid_match_id(hdev, hdrv->id_table);
}
EXPORT_SYMBOL_GPL(hid_match_device);
static int hid_bus_match(struct device *dev, struct device_driver *drv)
{
struct hid_driver *hdrv = to_hid_driver(drv);
struct hid_device *hdev = to_hid_device(dev);
return hid_match_device(hdev, hdrv) != NULL;
}
/**
* hid_compare_device_paths - check if both devices share the same path
* @hdev_a: hid device
* @hdev_b: hid device
* @separator: char to use as separator
*
* Check if two devices share the same path up to the last occurrence of
* the separator char. Both paths must exist (i.e., zero-length paths
* don't match).
*/
bool hid_compare_device_paths(struct hid_device *hdev_a,
struct hid_device *hdev_b, char separator)
{
int n1 = strrchr(hdev_a->phys, separator) - hdev_a->phys;
int n2 = strrchr(hdev_b->phys, separator) - hdev_b->phys;
if (n1 != n2 || n1 <= 0 || n2 <= 0)
return false;
return !strncmp(hdev_a->phys, hdev_b->phys, n1);
}
EXPORT_SYMBOL_GPL(hid_compare_device_paths);
static int hid_device_probe(struct device *dev)
{
struct hid_driver *hdrv = to_hid_driver(dev->driver);
struct hid_device *hdev = to_hid_device(dev);
const struct hid_device_id *id;
int ret = 0;
HID: Separate struct hid_device's driver_lock into two locks. This patch separates struct hid_device's driver_lock into two. The goal is to allow hid device drivers to receive input during their probe() or remove() function calls. This is necessary because some drivers need to communicate with the device to determine parameters needed during probe (e.g., size of a multi-touch surface), and if possible, may perfer to communicate with a device on host-initiated disconnect (e.g., to put it into a low-power state). Historically, three functions used driver_lock: - hid_device_probe: blocks to acquire lock - hid_device_remove: blocks to acquire lock - hid_input_report: if locked returns -EBUSY, else acquires lock This patch adds another lock (driver_input_lock) which is used to block input from occurring. The lock behavior is now: - hid_device_probe: blocks to acq. driver_lock, then driver_input_lock - hid_device_remove: blocks to acq. driver_lock, then driver_input_lock - hid_input_report: if driver_input_lock locked returns -EBUSY, else acquires driver_input_lock This patch also adds two helper functions to be called during probe() or remove(): hid_device_io_start() and hid_device_io_stop(). These functions lock and unlock, respectively, driver_input_lock; they also make a note of whether they did so that hid-core knows if a driver has changed the lock state. This patch results in no behavior change for existing devices and drivers. However, during a probe() or remove() function call in a driver, that driver may now selectively call hid_device_io_start() to let input events come through, then optionally call hid_device_io_stop() to stop them. Signed-off-by: Andrew de los Reyes <adlr@chromium.org> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2013-02-18 17:20:21 +00:00
if (down_interruptible(&hdev->driver_input_lock)) {
ret = -EINTR;
goto end;
HID: Separate struct hid_device's driver_lock into two locks. This patch separates struct hid_device's driver_lock into two. The goal is to allow hid device drivers to receive input during their probe() or remove() function calls. This is necessary because some drivers need to communicate with the device to determine parameters needed during probe (e.g., size of a multi-touch surface), and if possible, may perfer to communicate with a device on host-initiated disconnect (e.g., to put it into a low-power state). Historically, three functions used driver_lock: - hid_device_probe: blocks to acquire lock - hid_device_remove: blocks to acquire lock - hid_input_report: if locked returns -EBUSY, else acquires lock This patch adds another lock (driver_input_lock) which is used to block input from occurring. The lock behavior is now: - hid_device_probe: blocks to acq. driver_lock, then driver_input_lock - hid_device_remove: blocks to acq. driver_lock, then driver_input_lock - hid_input_report: if driver_input_lock locked returns -EBUSY, else acquires driver_input_lock This patch also adds two helper functions to be called during probe() or remove(): hid_device_io_start() and hid_device_io_stop(). These functions lock and unlock, respectively, driver_input_lock; they also make a note of whether they did so that hid-core knows if a driver has changed the lock state. This patch results in no behavior change for existing devices and drivers. However, during a probe() or remove() function call in a driver, that driver may now selectively call hid_device_io_start() to let input events come through, then optionally call hid_device_io_stop() to stop them. Signed-off-by: Andrew de los Reyes <adlr@chromium.org> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2013-02-18 17:20:21 +00:00
}
hdev->io_started = false;
HID: Fix race condition between driver core and ll-driver HID low level drivers register new devices with the HID core which then adds the devices to the HID bus. The HID bus normally immediately probes an appropriate driver which then handles HID input for this device. The ll driver now uses the hid_input_report() function to report input events for a specific device. However, if the HID bus unloads the driver at the same time (for instance via a call to /sys/bus/hid/devices/<dev>/unbind) then the hdev->driver pointer may be used by hid_input_report() and hid_device_remove() at the same time which may cause hdev->driver to point to invalid memory. This fix adds a semaphore to every hid device which protects hdev->driver from asynchronous access. This semaphore is locked during driver *_probe and *_remove and also inside hid_input_report(). The *_probe and *_remove functions may sleep so the semaphore is good here, however, hid_input_report() is in atomic context and hence only uses down_trylock(). If it cannot acquire the lock it simply drops the input package. The low-level drivers report input events synchronously so hid_input_report() should never be entered twice at the same time on the same device. Hence, the lock should always be available. But if the driver is currently probed/removed then the lock is not available and dropping the package should be safe because this is what would have happened if the package arrived some milliseconds earlier/later. This also fixes another race condition while probing drivers: First the *_probe function of the driver is called and only if that succeeds, the related input device of hidinput is registered. If the low level driver reports input events after the *_probe function returned but before the input device is registered, then a NULL pointer dereference will occur. (Equivalently on driver remove function). This is not possible anymore, since the semaphore lock drops all incoming packages until the driver/device is fully initialized. Signed-off-by: David Herrmann <dh.herrmann@googlemail.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2011-08-10 12:02:07 +00:00
clear_bit(ffs(HID_STAT_REPROBED), &hdev->status);
if (!hdev->driver) {
id = hid_match_device(hdev, hdrv);
if (id == NULL) {
ret = -ENODEV;
goto unlock;
}
if (hdrv->match) {
if (!hdrv->match(hdev, hid_ignore_special_drivers)) {
ret = -ENODEV;
goto unlock;
}
} else {
/*
* hid-generic implements .match(), so if
* hid_ignore_special_drivers is set, we can safely
* return.
*/
if (hid_ignore_special_drivers) {
ret = -ENODEV;
goto unlock;
}
}
/* reset the quirks that has been previously set */
hdev->quirks = hid_lookup_quirk(hdev);
hdev->driver = hdrv;
if (hdrv->probe) {
ret = hdrv->probe(hdev, id);
} else { /* default probe */
ret = hid_open_report(hdev);
if (!ret)
ret = hid_hw_start(hdev, HID_CONNECT_DEFAULT);
}
if (ret) {
hid_close_report(hdev);
hdev->driver = NULL;
}
}
unlock:
HID: Separate struct hid_device's driver_lock into two locks. This patch separates struct hid_device's driver_lock into two. The goal is to allow hid device drivers to receive input during their probe() or remove() function calls. This is necessary because some drivers need to communicate with the device to determine parameters needed during probe (e.g., size of a multi-touch surface), and if possible, may perfer to communicate with a device on host-initiated disconnect (e.g., to put it into a low-power state). Historically, three functions used driver_lock: - hid_device_probe: blocks to acquire lock - hid_device_remove: blocks to acquire lock - hid_input_report: if locked returns -EBUSY, else acquires lock This patch adds another lock (driver_input_lock) which is used to block input from occurring. The lock behavior is now: - hid_device_probe: blocks to acq. driver_lock, then driver_input_lock - hid_device_remove: blocks to acq. driver_lock, then driver_input_lock - hid_input_report: if driver_input_lock locked returns -EBUSY, else acquires driver_input_lock This patch also adds two helper functions to be called during probe() or remove(): hid_device_io_start() and hid_device_io_stop(). These functions lock and unlock, respectively, driver_input_lock; they also make a note of whether they did so that hid-core knows if a driver has changed the lock state. This patch results in no behavior change for existing devices and drivers. However, during a probe() or remove() function call in a driver, that driver may now selectively call hid_device_io_start() to let input events come through, then optionally call hid_device_io_stop() to stop them. Signed-off-by: Andrew de los Reyes <adlr@chromium.org> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2013-02-18 17:20:21 +00:00
if (!hdev->io_started)
up(&hdev->driver_input_lock);
end:
return ret;
}
bus: Make remove callback return void The driver core ignores the return value of this callback because there is only little it can do when a device disappears. This is the final bit of a long lasting cleanup quest where several buses were converted to also return void from their remove callback. Additionally some resource leaks were fixed that were caused by drivers returning an error code in the expectation that the driver won't go away. With struct bus_type::remove returning void it's prevented that newly implemented buses return an ignored error code and so don't anticipate wrong expectations for driver authors. Reviewed-by: Tom Rix <trix@redhat.com> (For fpga) Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org> Reviewed-by: Cornelia Huck <cohuck@redhat.com> (For drivers/s390 and drivers/vfio) Acked-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> (For ARM, Amba and related parts) Acked-by: Mark Brown <broonie@kernel.org> Acked-by: Chen-Yu Tsai <wens@csie.org> (for sunxi-rsb) Acked-by: Pali Rohár <pali@kernel.org> Acked-by: Mauro Carvalho Chehab <mchehab@kernel.org> (for media) Acked-by: Hans de Goede <hdegoede@redhat.com> (For drivers/platform) Acked-by: Alexandre Belloni <alexandre.belloni@bootlin.com> Acked-By: Vinod Koul <vkoul@kernel.org> Acked-by: Juergen Gross <jgross@suse.com> (For xen) Acked-by: Lee Jones <lee.jones@linaro.org> (For mfd) Acked-by: Johannes Thumshirn <jth@kernel.org> (For mcb) Acked-by: Johan Hovold <johan@kernel.org> Acked-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> (For slimbus) Acked-by: Kirti Wankhede <kwankhede@nvidia.com> (For vfio) Acked-by: Maximilian Luz <luzmaximilian@gmail.com> Acked-by: Heikki Krogerus <heikki.krogerus@linux.intel.com> (For ulpi and typec) Acked-by: Samuel Iglesias Gonsálvez <siglesias@igalia.com> (For ipack) Acked-by: Geoff Levand <geoff@infradead.org> (For ps3) Acked-by: Yehezkel Bernat <YehezkelShB@gmail.com> (For thunderbolt) Acked-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> (For intel_th) Acked-by: Dominik Brodowski <linux@dominikbrodowski.net> (For pcmcia) Acked-by: Rafael J. Wysocki <rafael@kernel.org> (For ACPI) Acked-by: Bjorn Andersson <bjorn.andersson@linaro.org> (rpmsg and apr) Acked-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> (For intel-ish-hid) Acked-by: Dan Williams <dan.j.williams@intel.com> (For CXL, DAX, and NVDIMM) Acked-by: William Breathitt Gray <vilhelm.gray@gmail.com> (For isa) Acked-by: Stefan Richter <stefanr@s5r6.in-berlin.de> (For firewire) Acked-by: Benjamin Tissoires <benjamin.tissoires@redhat.com> (For hid) Acked-by: Thorsten Scherer <t.scherer@eckelmann.de> (For siox) Acked-by: Sven Van Asbroeck <TheSven73@gmail.com> (For anybuss) Acked-by: Ulf Hansson <ulf.hansson@linaro.org> (For MMC) Acked-by: Wolfram Sang <wsa@kernel.org> # for I2C Acked-by: Sudeep Holla <sudeep.holla@arm.com> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> Acked-by: Finn Thain <fthain@linux-m68k.org> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Link: https://lore.kernel.org/r/20210713193522.1770306-6-u.kleine-koenig@pengutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-07-13 19:35:22 +00:00
static void hid_device_remove(struct device *dev)
{
struct hid_device *hdev = to_hid_device(dev);
HID: Fix race condition between driver core and ll-driver HID low level drivers register new devices with the HID core which then adds the devices to the HID bus. The HID bus normally immediately probes an appropriate driver which then handles HID input for this device. The ll driver now uses the hid_input_report() function to report input events for a specific device. However, if the HID bus unloads the driver at the same time (for instance via a call to /sys/bus/hid/devices/<dev>/unbind) then the hdev->driver pointer may be used by hid_input_report() and hid_device_remove() at the same time which may cause hdev->driver to point to invalid memory. This fix adds a semaphore to every hid device which protects hdev->driver from asynchronous access. This semaphore is locked during driver *_probe and *_remove and also inside hid_input_report(). The *_probe and *_remove functions may sleep so the semaphore is good here, however, hid_input_report() is in atomic context and hence only uses down_trylock(). If it cannot acquire the lock it simply drops the input package. The low-level drivers report input events synchronously so hid_input_report() should never be entered twice at the same time on the same device. Hence, the lock should always be available. But if the driver is currently probed/removed then the lock is not available and dropping the package should be safe because this is what would have happened if the package arrived some milliseconds earlier/later. This also fixes another race condition while probing drivers: First the *_probe function of the driver is called and only if that succeeds, the related input device of hidinput is registered. If the low level driver reports input events after the *_probe function returned but before the input device is registered, then a NULL pointer dereference will occur. (Equivalently on driver remove function). This is not possible anymore, since the semaphore lock drops all incoming packages until the driver/device is fully initialized. Signed-off-by: David Herrmann <dh.herrmann@googlemail.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2011-08-10 12:02:07 +00:00
struct hid_driver *hdrv;
down(&hdev->driver_input_lock);
HID: Separate struct hid_device's driver_lock into two locks. This patch separates struct hid_device's driver_lock into two. The goal is to allow hid device drivers to receive input during their probe() or remove() function calls. This is necessary because some drivers need to communicate with the device to determine parameters needed during probe (e.g., size of a multi-touch surface), and if possible, may perfer to communicate with a device on host-initiated disconnect (e.g., to put it into a low-power state). Historically, three functions used driver_lock: - hid_device_probe: blocks to acquire lock - hid_device_remove: blocks to acquire lock - hid_input_report: if locked returns -EBUSY, else acquires lock This patch adds another lock (driver_input_lock) which is used to block input from occurring. The lock behavior is now: - hid_device_probe: blocks to acq. driver_lock, then driver_input_lock - hid_device_remove: blocks to acq. driver_lock, then driver_input_lock - hid_input_report: if driver_input_lock locked returns -EBUSY, else acquires driver_input_lock This patch also adds two helper functions to be called during probe() or remove(): hid_device_io_start() and hid_device_io_stop(). These functions lock and unlock, respectively, driver_input_lock; they also make a note of whether they did so that hid-core knows if a driver has changed the lock state. This patch results in no behavior change for existing devices and drivers. However, during a probe() or remove() function call in a driver, that driver may now selectively call hid_device_io_start() to let input events come through, then optionally call hid_device_io_stop() to stop them. Signed-off-by: Andrew de los Reyes <adlr@chromium.org> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2013-02-18 17:20:21 +00:00
hdev->io_started = false;
HID: Fix race condition between driver core and ll-driver HID low level drivers register new devices with the HID core which then adds the devices to the HID bus. The HID bus normally immediately probes an appropriate driver which then handles HID input for this device. The ll driver now uses the hid_input_report() function to report input events for a specific device. However, if the HID bus unloads the driver at the same time (for instance via a call to /sys/bus/hid/devices/<dev>/unbind) then the hdev->driver pointer may be used by hid_input_report() and hid_device_remove() at the same time which may cause hdev->driver to point to invalid memory. This fix adds a semaphore to every hid device which protects hdev->driver from asynchronous access. This semaphore is locked during driver *_probe and *_remove and also inside hid_input_report(). The *_probe and *_remove functions may sleep so the semaphore is good here, however, hid_input_report() is in atomic context and hence only uses down_trylock(). If it cannot acquire the lock it simply drops the input package. The low-level drivers report input events synchronously so hid_input_report() should never be entered twice at the same time on the same device. Hence, the lock should always be available. But if the driver is currently probed/removed then the lock is not available and dropping the package should be safe because this is what would have happened if the package arrived some milliseconds earlier/later. This also fixes another race condition while probing drivers: First the *_probe function of the driver is called and only if that succeeds, the related input device of hidinput is registered. If the low level driver reports input events after the *_probe function returned but before the input device is registered, then a NULL pointer dereference will occur. (Equivalently on driver remove function). This is not possible anymore, since the semaphore lock drops all incoming packages until the driver/device is fully initialized. Signed-off-by: David Herrmann <dh.herrmann@googlemail.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2011-08-10 12:02:07 +00:00
hdrv = hdev->driver;
if (hdrv) {
if (hdrv->remove)
hdrv->remove(hdev);
else /* default remove */
hid_hw_stop(hdev);
hid_close_report(hdev);
hdev->driver = NULL;
}
HID: Separate struct hid_device's driver_lock into two locks. This patch separates struct hid_device's driver_lock into two. The goal is to allow hid device drivers to receive input during their probe() or remove() function calls. This is necessary because some drivers need to communicate with the device to determine parameters needed during probe (e.g., size of a multi-touch surface), and if possible, may perfer to communicate with a device on host-initiated disconnect (e.g., to put it into a low-power state). Historically, three functions used driver_lock: - hid_device_probe: blocks to acquire lock - hid_device_remove: blocks to acquire lock - hid_input_report: if locked returns -EBUSY, else acquires lock This patch adds another lock (driver_input_lock) which is used to block input from occurring. The lock behavior is now: - hid_device_probe: blocks to acq. driver_lock, then driver_input_lock - hid_device_remove: blocks to acq. driver_lock, then driver_input_lock - hid_input_report: if driver_input_lock locked returns -EBUSY, else acquires driver_input_lock This patch also adds two helper functions to be called during probe() or remove(): hid_device_io_start() and hid_device_io_stop(). These functions lock and unlock, respectively, driver_input_lock; they also make a note of whether they did so that hid-core knows if a driver has changed the lock state. This patch results in no behavior change for existing devices and drivers. However, during a probe() or remove() function call in a driver, that driver may now selectively call hid_device_io_start() to let input events come through, then optionally call hid_device_io_stop() to stop them. Signed-off-by: Andrew de los Reyes <adlr@chromium.org> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2013-02-18 17:20:21 +00:00
if (!hdev->io_started)
up(&hdev->driver_input_lock);
}
static ssize_t modalias_show(struct device *dev, struct device_attribute *a,
char *buf)
{
struct hid_device *hdev = container_of(dev, struct hid_device, dev);
return scnprintf(buf, PAGE_SIZE, "hid:b%04Xg%04Xv%08Xp%08X\n",
hdev->bus, hdev->group, hdev->vendor, hdev->product);
}
static DEVICE_ATTR_RO(modalias);
static struct attribute *hid_dev_attrs[] = {
&dev_attr_modalias.attr,
NULL,
};
static struct bin_attribute *hid_dev_bin_attrs[] = {
&dev_bin_attr_report_desc,
NULL
};
static const struct attribute_group hid_dev_group = {
.attrs = hid_dev_attrs,
.bin_attrs = hid_dev_bin_attrs,
};
__ATTRIBUTE_GROUPS(hid_dev);
static int hid_uevent(struct device *dev, struct kobj_uevent_env *env)
{
struct hid_device *hdev = to_hid_device(dev);
if (add_uevent_var(env, "HID_ID=%04X:%08X:%08X",
hdev->bus, hdev->vendor, hdev->product))
return -ENOMEM;
if (add_uevent_var(env, "HID_NAME=%s", hdev->name))
return -ENOMEM;
if (add_uevent_var(env, "HID_PHYS=%s", hdev->phys))
return -ENOMEM;
if (add_uevent_var(env, "HID_UNIQ=%s", hdev->uniq))
return -ENOMEM;
if (add_uevent_var(env, "MODALIAS=hid:b%04Xg%04Xv%08Xp%08X",
hdev->bus, hdev->group, hdev->vendor, hdev->product))
return -ENOMEM;
return 0;
}
struct bus_type hid_bus_type = {
.name = "hid",
.dev_groups = hid_dev_groups,
.drv_groups = hid_drv_groups,
.match = hid_bus_match,
.probe = hid_device_probe,
.remove = hid_device_remove,
.uevent = hid_uevent,
};
EXPORT_SYMBOL(hid_bus_type);
int hid_add_device(struct hid_device *hdev)
{
static atomic_t id = ATOMIC_INIT(0);
int ret;
if (WARN_ON(hdev->status & HID_STAT_ADDED))
return -EBUSY;
hdev->quirks = hid_lookup_quirk(hdev);
/* we need to kill them here, otherwise they will stay allocated to
* wait for coming driver */
if (hid_ignore(hdev))
return -ENODEV;
/*
* Check for the mandatory transport channel.
*/
if (!hdev->ll_driver->raw_request) {
hid_err(hdev, "transport driver missing .raw_request()\n");
return -EINVAL;
}
/*
* Read the device report descriptor once and use as template
* for the driver-specific modifications.
*/
ret = hdev->ll_driver->parse(hdev);
if (ret)
return ret;
if (!hdev->dev_rdesc)
return -ENODEV;
/*
* Scan generic devices for group information
*/
if (hid_ignore_special_drivers) {
hdev->group = HID_GROUP_GENERIC;
} else if (!hdev->group &&
!(hdev->quirks & HID_QUIRK_HAVE_SPECIAL_DRIVER)) {
ret = hid_scan_report(hdev);
if (ret)
hid_warn(hdev, "bad device descriptor (%d)\n", ret);
}
/* XXX hack, any other cleaner solution after the driver core
* is converted to allow more than 20 bytes as the device name? */
dev_set_name(&hdev->dev, "%04X:%04X:%04X.%04X", hdev->bus,
hdev->vendor, hdev->product, atomic_inc_return(&id));
hid_debug_register(hdev, dev_name(&hdev->dev));
ret = device_add(&hdev->dev);
if (!ret)
hdev->status |= HID_STAT_ADDED;
else
hid_debug_unregister(hdev);
return ret;
}
EXPORT_SYMBOL_GPL(hid_add_device);
/**
* hid_allocate_device - allocate new hid device descriptor
*
* Allocate and initialize hid device, so that hid_destroy_device might be
* used to free it.
*
* New hid_device pointer is returned on success, otherwise ERR_PTR encoded
* error value.
*/
struct hid_device *hid_allocate_device(void)
{
struct hid_device *hdev;
int ret = -ENOMEM;
hdev = kzalloc(sizeof(*hdev), GFP_KERNEL);
if (hdev == NULL)
return ERR_PTR(ret);
device_initialize(&hdev->dev);
hdev->dev.release = hid_device_release;
hdev->dev.bus = &hid_bus_type;
device_enable_async_suspend(&hdev->dev);
hid_close_report(hdev);
init_waitqueue_head(&hdev->debug_wait);
INIT_LIST_HEAD(&hdev->debug_list);
HID: debug: fix RCU preemption issue Commit 2353f2bea ("HID: protect hid_debug_list") introduced mutex locking around debug_list access to prevent SMP races when debugfs nodes are being operated upon by multiple userspace processess. mutex is not a proper synchronization primitive though, as the hid-debug callbacks are being called from atomic contexts. We also have to be careful about disabling IRQs when taking the lock to prevent deadlock against IRQ handlers. Benjamin reports this has also been reported in RH bugzilla as bug #958935. =============================== [ INFO: suspicious RCU usage. ] 3.9.0+ #94 Not tainted ------------------------------- include/linux/rcupdate.h:476 Illegal context switch in RCU read-side critical section! other info that might help us debug this: rcu_scheduler_active = 1, debug_locks = 0 4 locks held by Xorg/5502: #0: (&evdev->mutex){+.+...}, at: [<ffffffff81512c3d>] evdev_write+0x6d/0x160 #1: (&(&dev->event_lock)->rlock#2){-.-...}, at: [<ffffffff8150dd9b>] input_inject_event+0x5b/0x230 #2: (rcu_read_lock){.+.+..}, at: [<ffffffff8150dd82>] input_inject_event+0x42/0x230 #3: (&(&usbhid->lock)->rlock){-.....}, at: [<ffffffff81565289>] usb_hidinput_input_event+0x89/0x120 stack backtrace: CPU: 0 PID: 5502 Comm: Xorg Not tainted 3.9.0+ #94 Hardware name: Dell Inc. OptiPlex 390/0M5DCD, BIOS A09 07/24/2012 0000000000000001 ffff8800689c7c38 ffffffff816f249f ffff8800689c7c68 ffffffff810acb1d 0000000000000000 ffffffff81a03ac7 000000000000019d 0000000000000000 ffff8800689c7c90 ffffffff8107cda7 0000000000000000 Call Trace: [<ffffffff816f249f>] dump_stack+0x19/0x1b [<ffffffff810acb1d>] lockdep_rcu_suspicious+0xfd/0x130 [<ffffffff8107cda7>] __might_sleep+0xc7/0x230 [<ffffffff816f7770>] mutex_lock_nested+0x40/0x3a0 [<ffffffff81312ac4>] ? vsnprintf+0x354/0x640 [<ffffffff81553cc4>] hid_debug_event+0x34/0x100 [<ffffffff81554197>] hid_dump_input+0x67/0xa0 [<ffffffff81556430>] hid_set_field+0x50/0x120 [<ffffffff8156529a>] usb_hidinput_input_event+0x9a/0x120 [<ffffffff8150d89e>] input_handle_event+0x8e/0x530 [<ffffffff8150df10>] input_inject_event+0x1d0/0x230 [<ffffffff8150dd82>] ? input_inject_event+0x42/0x230 [<ffffffff81512cae>] evdev_write+0xde/0x160 [<ffffffff81185038>] vfs_write+0xc8/0x1f0 [<ffffffff81185535>] SyS_write+0x55/0xa0 [<ffffffff81704482>] system_call_fastpath+0x16/0x1b BUG: sleeping function called from invalid context at kernel/mutex.c:413 in_atomic(): 1, irqs_disabled(): 1, pid: 5502, name: Xorg INFO: lockdep is turned off. irq event stamp: 1098574 hardirqs last enabled at (1098573): [<ffffffff816fb53f>] _raw_spin_unlock_irqrestore+0x3f/0x70 hardirqs last disabled at (1098574): [<ffffffff816faaf5>] _raw_spin_lock_irqsave+0x25/0xa0 softirqs last enabled at (1098306): [<ffffffff8104971f>] __do_softirq+0x18f/0x3c0 softirqs last disabled at (1097867): [<ffffffff81049ad5>] irq_exit+0xa5/0xb0 CPU: 0 PID: 5502 Comm: Xorg Not tainted 3.9.0+ #94 Hardware name: Dell Inc. OptiPlex 390/0M5DCD, BIOS A09 07/24/2012 ffffffff81a03ac7 ffff8800689c7c68 ffffffff816f249f ffff8800689c7c90 ffffffff8107ce60 0000000000000000 ffff8800689c7fd8 ffff88006a62c800 ffff8800689c7d10 ffffffff816f7770 ffff8800689c7d00 ffffffff81312ac4 Call Trace: [<ffffffff816f249f>] dump_stack+0x19/0x1b [<ffffffff8107ce60>] __might_sleep+0x180/0x230 [<ffffffff816f7770>] mutex_lock_nested+0x40/0x3a0 [<ffffffff81312ac4>] ? vsnprintf+0x354/0x640 [<ffffffff81553cc4>] hid_debug_event+0x34/0x100 [<ffffffff81554197>] hid_dump_input+0x67/0xa0 [<ffffffff81556430>] hid_set_field+0x50/0x120 [<ffffffff8156529a>] usb_hidinput_input_event+0x9a/0x120 [<ffffffff8150d89e>] input_handle_event+0x8e/0x530 [<ffffffff8150df10>] input_inject_event+0x1d0/0x230 [<ffffffff8150dd82>] ? input_inject_event+0x42/0x230 [<ffffffff81512cae>] evdev_write+0xde/0x160 [<ffffffff81185038>] vfs_write+0xc8/0x1f0 [<ffffffff81185535>] SyS_write+0x55/0xa0 [<ffffffff81704482>] system_call_fastpath+0x16/0x1b Reported-by: majianpeng <majianpeng@gmail.com> Reported-by: Benjamin Tissoires <benjamin.tissoires@gmail.com> Reviewed-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2013-05-06 11:05:50 +00:00
spin_lock_init(&hdev->debug_list_lock);
HID: Separate struct hid_device's driver_lock into two locks. This patch separates struct hid_device's driver_lock into two. The goal is to allow hid device drivers to receive input during their probe() or remove() function calls. This is necessary because some drivers need to communicate with the device to determine parameters needed during probe (e.g., size of a multi-touch surface), and if possible, may perfer to communicate with a device on host-initiated disconnect (e.g., to put it into a low-power state). Historically, three functions used driver_lock: - hid_device_probe: blocks to acquire lock - hid_device_remove: blocks to acquire lock - hid_input_report: if locked returns -EBUSY, else acquires lock This patch adds another lock (driver_input_lock) which is used to block input from occurring. The lock behavior is now: - hid_device_probe: blocks to acq. driver_lock, then driver_input_lock - hid_device_remove: blocks to acq. driver_lock, then driver_input_lock - hid_input_report: if driver_input_lock locked returns -EBUSY, else acquires driver_input_lock This patch also adds two helper functions to be called during probe() or remove(): hid_device_io_start() and hid_device_io_stop(). These functions lock and unlock, respectively, driver_input_lock; they also make a note of whether they did so that hid-core knows if a driver has changed the lock state. This patch results in no behavior change for existing devices and drivers. However, during a probe() or remove() function call in a driver, that driver may now selectively call hid_device_io_start() to let input events come through, then optionally call hid_device_io_stop() to stop them. Signed-off-by: Andrew de los Reyes <adlr@chromium.org> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2013-02-18 17:20:21 +00:00
sema_init(&hdev->driver_input_lock, 1);
mutex_init(&hdev->ll_open_lock);
return hdev;
}
EXPORT_SYMBOL_GPL(hid_allocate_device);
static void hid_remove_device(struct hid_device *hdev)
{
if (hdev->status & HID_STAT_ADDED) {
device_del(&hdev->dev);
hid_debug_unregister(hdev);
hdev->status &= ~HID_STAT_ADDED;
}
kfree(hdev->dev_rdesc);
hdev->dev_rdesc = NULL;
hdev->dev_rsize = 0;
}
/**
* hid_destroy_device - free previously allocated device
*
* @hdev: hid device
*
* If you allocate hid_device through hid_allocate_device, you should ever
* free by this function.
*/
void hid_destroy_device(struct hid_device *hdev)
{
hid_remove_device(hdev);
put_device(&hdev->dev);
}
EXPORT_SYMBOL_GPL(hid_destroy_device);
static int __hid_bus_reprobe_drivers(struct device *dev, void *data)
{
struct hid_driver *hdrv = data;
struct hid_device *hdev = to_hid_device(dev);
if (hdev->driver == hdrv &&
!hdrv->match(hdev, hid_ignore_special_drivers) &&
!test_and_set_bit(ffs(HID_STAT_REPROBED), &hdev->status))
return device_reprobe(dev);
return 0;
}
static int __hid_bus_driver_added(struct device_driver *drv, void *data)
{
struct hid_driver *hdrv = to_hid_driver(drv);
if (hdrv->match) {
bus_for_each_dev(&hid_bus_type, NULL, hdrv,
__hid_bus_reprobe_drivers);
}
return 0;
}
static int __bus_removed_driver(struct device_driver *drv, void *data)
{
return bus_rescan_devices(&hid_bus_type);
}
int __hid_register_driver(struct hid_driver *hdrv, struct module *owner,
const char *mod_name)
{
int ret;
hdrv->driver.name = hdrv->name;
hdrv->driver.bus = &hid_bus_type;
hdrv->driver.owner = owner;
hdrv->driver.mod_name = mod_name;
INIT_LIST_HEAD(&hdrv->dyn_list);
spin_lock_init(&hdrv->dyn_lock);
ret = driver_register(&hdrv->driver);
if (ret == 0)
bus_for_each_drv(&hid_bus_type, NULL, NULL,
__hid_bus_driver_added);
return ret;
}
EXPORT_SYMBOL_GPL(__hid_register_driver);
void hid_unregister_driver(struct hid_driver *hdrv)
{
driver_unregister(&hdrv->driver);
hid_free_dynids(hdrv);
bus_for_each_drv(&hid_bus_type, NULL, hdrv, __bus_removed_driver);
}
EXPORT_SYMBOL_GPL(hid_unregister_driver);
int hid_check_keys_pressed(struct hid_device *hid)
{
struct hid_input *hidinput;
int i;
if (!(hid->claimed & HID_CLAIMED_INPUT))
return 0;
list_for_each_entry(hidinput, &hid->inputs, list) {
for (i = 0; i < BITS_TO_LONGS(KEY_MAX); i++)
if (hidinput->input->key[i])
return 1;
}
return 0;
}
EXPORT_SYMBOL_GPL(hid_check_keys_pressed);
static int __init hid_init(void)
{
int ret;
if (hid_debug)
pr_warn("hid_debug is now used solely for parser and driver debugging.\n"
"debugfs is now used for inspecting the device (report descriptor, reports)\n");
ret = bus_register(&hid_bus_type);
if (ret) {
pr_err("can't register hid bus\n");
goto err;
}
ret = hidraw_init();
if (ret)
goto err_bus;
hid_debug_init();
return 0;
err_bus:
bus_unregister(&hid_bus_type);
err:
return ret;
}
static void __exit hid_exit(void)
{
hid_debug_exit();
hidraw_exit();
bus_unregister(&hid_bus_type);
hid_quirks_exit(HID_BUS_ANY);
}
module_init(hid_init);
module_exit(hid_exit);
MODULE_AUTHOR("Andreas Gal");
MODULE_AUTHOR("Vojtech Pavlik");
MODULE_AUTHOR("Jiri Kosina");
MODULE_LICENSE("GPL");