linux/drivers/platform/x86/dell-wmi.c
Pali Rohár 83fc44c32a dell-wmi: Update code for processing WMI events
The WMI buffer can contain multiple events. First value in buffer is
length of event followed by data of specified length. After that is next
length and next data.  When length is zero then there is no more events
in bufffer.

This patch adds support for processing all events in buffer (not only
first) and parse more event types (not only hotkey events). Because of
variable length of events sometimes BIOS fills more hotkeys (or other
values) into single WMI event. In this case this patch also processes
these multiple hotkeys (and not only first one).

Some event types are just ignored because kernel is not interested in
them (e.g. NIC Link status, battery unplug, ...).

This patch is based on DSDT table from Dell Latitude E6440. Code should
be backward compatible so will process other events of old types same as
before this patch.

This patch also fixes a problem with unknown WMI event messages being
written to the log. Now all known events are parsed and those which are
not interesting to the kernel are dropped without an unknown WMI event
message.

Signed-off-by: Pali Rohár <pali.rohar@gmail.com>
Tested-by: Pali Rohár <pali.rohar@gmail.com>
Signed-off-by: Darren Hart <dvhart@linux.intel.com>
2014-11-19 09:25:31 -08:00

421 lines
11 KiB
C

/*
* Dell WMI hotkeys
*
* Copyright (C) 2008 Red Hat <mjg@redhat.com>
*
* Portions based on wistron_btns.c:
* Copyright (C) 2005 Miloslav Trmac <mitr@volny.cz>
* Copyright (C) 2005 Bernhard Rosenkraenzer <bero@arklinux.org>
* Copyright (C) 2005 Dmitry Torokhov <dtor@mail.ru>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/types.h>
#include <linux/input.h>
#include <linux/input/sparse-keymap.h>
#include <linux/acpi.h>
#include <linux/string.h>
#include <linux/dmi.h>
MODULE_AUTHOR("Matthew Garrett <mjg@redhat.com>");
MODULE_DESCRIPTION("Dell laptop WMI hotkeys driver");
MODULE_LICENSE("GPL");
#define DELL_EVENT_GUID "9DBB5994-A997-11DA-B012-B622A1EF5492"
static int acpi_video;
MODULE_ALIAS("wmi:"DELL_EVENT_GUID);
/*
* Certain keys are flagged as KE_IGNORE. All of these are either
* notifications (rather than requests for change) or are also sent
* via the keyboard controller so should not be sent again.
*/
static const struct key_entry dell_wmi_legacy_keymap[] __initconst = {
{ KE_IGNORE, 0x003a, { KEY_CAPSLOCK } },
{ KE_KEY, 0xe045, { KEY_PROG1 } },
{ KE_KEY, 0xe009, { KEY_EJECTCD } },
/* These also contain the brightness level at offset 6 */
{ KE_KEY, 0xe006, { KEY_BRIGHTNESSUP } },
{ KE_KEY, 0xe005, { KEY_BRIGHTNESSDOWN } },
/* Battery health status button */
{ KE_KEY, 0xe007, { KEY_BATTERY } },
/* This is actually for all radios. Although physically a
* switch, the notification does not provide an indication of
* state and so it should be reported as a key */
{ KE_KEY, 0xe008, { KEY_WLAN } },
/* The next device is at offset 6, the active devices are at
offset 8 and the attached devices at offset 10 */
{ KE_KEY, 0xe00b, { KEY_SWITCHVIDEOMODE } },
{ KE_IGNORE, 0xe00c, { KEY_KBDILLUMTOGGLE } },
/* BIOS error detected */
{ KE_IGNORE, 0xe00d, { KEY_RESERVED } },
/* Wifi Catcher */
{ KE_KEY, 0xe011, {KEY_PROG2 } },
/* Ambient light sensor toggle */
{ KE_IGNORE, 0xe013, { KEY_RESERVED } },
{ KE_IGNORE, 0xe020, { KEY_MUTE } },
/* Shortcut and audio panel keys */
{ KE_IGNORE, 0xe025, { KEY_RESERVED } },
{ KE_IGNORE, 0xe026, { KEY_RESERVED } },
{ KE_IGNORE, 0xe02e, { KEY_VOLUMEDOWN } },
{ KE_IGNORE, 0xe030, { KEY_VOLUMEUP } },
{ KE_IGNORE, 0xe033, { KEY_KBDILLUMUP } },
{ KE_IGNORE, 0xe034, { KEY_KBDILLUMDOWN } },
{ KE_IGNORE, 0xe03a, { KEY_CAPSLOCK } },
{ KE_IGNORE, 0xe045, { KEY_NUMLOCK } },
{ KE_IGNORE, 0xe046, { KEY_SCROLLLOCK } },
{ KE_IGNORE, 0xe0f7, { KEY_MUTE } },
{ KE_IGNORE, 0xe0f8, { KEY_VOLUMEDOWN } },
{ KE_IGNORE, 0xe0f9, { KEY_VOLUMEUP } },
{ KE_END, 0 }
};
static bool dell_new_hk_type;
struct dell_bios_keymap_entry {
u16 scancode;
u16 keycode;
};
struct dell_bios_hotkey_table {
struct dmi_header header;
struct dell_bios_keymap_entry keymap[];
};
static const struct dell_bios_hotkey_table *dell_bios_hotkey_table;
static const u16 bios_to_linux_keycode[256] __initconst = {
KEY_MEDIA, KEY_NEXTSONG, KEY_PLAYPAUSE, KEY_PREVIOUSSONG,
KEY_STOPCD, KEY_UNKNOWN, KEY_UNKNOWN, KEY_UNKNOWN,
KEY_WWW, KEY_UNKNOWN, KEY_VOLUMEDOWN, KEY_MUTE,
KEY_VOLUMEUP, KEY_UNKNOWN, KEY_BATTERY, KEY_EJECTCD,
KEY_UNKNOWN, KEY_SLEEP, KEY_PROG1, KEY_BRIGHTNESSDOWN,
KEY_BRIGHTNESSUP, KEY_UNKNOWN, KEY_KBDILLUMTOGGLE,
KEY_UNKNOWN, KEY_SWITCHVIDEOMODE, KEY_UNKNOWN, KEY_UNKNOWN,
KEY_SWITCHVIDEOMODE, KEY_UNKNOWN, KEY_UNKNOWN, KEY_PROG2,
KEY_UNKNOWN, KEY_UNKNOWN, KEY_UNKNOWN, KEY_UNKNOWN,
KEY_UNKNOWN, KEY_UNKNOWN, KEY_UNKNOWN, KEY_MICMUTE,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, KEY_PROG3
};
static struct input_dev *dell_wmi_input_dev;
static void dell_wmi_process_key(int reported_key)
{
const struct key_entry *key;
key = sparse_keymap_entry_from_scancode(dell_wmi_input_dev,
reported_key);
if (!key) {
pr_info("Unknown key %x pressed\n", reported_key);
return;
}
pr_debug("Key %x pressed\n", reported_key);
/* Don't report brightness notifications that will also come via ACPI */
if ((key->keycode == KEY_BRIGHTNESSUP ||
key->keycode == KEY_BRIGHTNESSDOWN) && acpi_video)
return;
sparse_keymap_report_entry(dell_wmi_input_dev, key, 1, true);
}
static void dell_wmi_notify(u32 value, void *context)
{
struct acpi_buffer response = { ACPI_ALLOCATE_BUFFER, NULL };
union acpi_object *obj;
acpi_status status;
acpi_size buffer_size;
u16 *buffer_entry, *buffer_end;
int len, i;
status = wmi_get_event_data(value, &response);
if (status != AE_OK) {
pr_warn("bad event status 0x%x\n", status);
return;
}
obj = (union acpi_object *)response.pointer;
if (!obj) {
pr_warn("no response\n");
return;
}
if (obj->type != ACPI_TYPE_BUFFER) {
pr_warn("bad response type %x\n", obj->type);
kfree(obj);
return;
}
pr_debug("Received WMI event (%*ph)\n",
obj->buffer.length, obj->buffer.pointer);
buffer_entry = (u16 *)obj->buffer.pointer;
buffer_size = obj->buffer.length/2;
if (!dell_new_hk_type) {
if (buffer_size >= 3 && buffer_entry[1] == 0x0)
dell_wmi_process_key(buffer_entry[2]);
else if (buffer_size >= 2)
dell_wmi_process_key(buffer_entry[1]);
else
pr_info("Received unknown WMI event\n");
kfree(obj);
return;
}
buffer_end = buffer_entry + buffer_size;
while (buffer_entry < buffer_end) {
len = buffer_entry[0];
if (len == 0)
break;
len++;
if (buffer_entry + len > buffer_end) {
pr_warn("Invalid length of WMI event\n");
break;
}
pr_debug("Process buffer (%*ph)\n", len*2, buffer_entry);
switch (buffer_entry[1]) {
case 0x00:
for (i = 2; i < len; ++i) {
switch (buffer_entry[i]) {
case 0xe043:
/* NIC Link is Up */
pr_debug("NIC Link is Up\n");
break;
case 0xe044:
/* NIC Link is Down */
pr_debug("NIC Link is Down\n");
break;
case 0xe045:
/* Unknown event but defined in DSDT */
default:
/* Unknown event */
pr_info("Unknown WMI event type 0x00: "
"0x%x\n", (int)buffer_entry[i]);
break;
}
}
break;
case 0x10:
/* Keys pressed */
for (i = 2; i < len; ++i)
dell_wmi_process_key(buffer_entry[i]);
break;
case 0x11:
for (i = 2; i < len; ++i) {
switch (buffer_entry[i]) {
case 0xfff0:
/* Battery unplugged */
pr_debug("Battery unplugged\n");
break;
case 0xfff1:
/* Battery inserted */
pr_debug("Battery inserted\n");
break;
case 0x01e1:
case 0x02ea:
case 0x02eb:
case 0x02ec:
case 0x02f6:
/* Keyboard backlight level changed */
pr_debug("Keyboard backlight level "
"changed\n");
break;
default:
/* Unknown event */
pr_info("Unknown WMI event type 0x11: "
"0x%x\n", (int)buffer_entry[i]);
break;
}
}
break;
default:
/* Unknown event */
pr_info("Unknown WMI event type 0x%x\n",
(int)buffer_entry[1]);
break;
}
buffer_entry += len;
}
kfree(obj);
}
static const struct key_entry * __init dell_wmi_prepare_new_keymap(void)
{
int hotkey_num = (dell_bios_hotkey_table->header.length - 4) /
sizeof(struct dell_bios_keymap_entry);
struct key_entry *keymap;
int i;
keymap = kcalloc(hotkey_num + 1, sizeof(struct key_entry), GFP_KERNEL);
if (!keymap)
return NULL;
for (i = 0; i < hotkey_num; i++) {
const struct dell_bios_keymap_entry *bios_entry =
&dell_bios_hotkey_table->keymap[i];
keymap[i].type = KE_KEY;
keymap[i].code = bios_entry->scancode;
keymap[i].keycode = bios_entry->keycode < 256 ?
bios_to_linux_keycode[bios_entry->keycode] :
KEY_RESERVED;
}
keymap[hotkey_num].type = KE_END;
return keymap;
}
static int __init dell_wmi_input_setup(void)
{
int err;
dell_wmi_input_dev = input_allocate_device();
if (!dell_wmi_input_dev)
return -ENOMEM;
dell_wmi_input_dev->name = "Dell WMI hotkeys";
dell_wmi_input_dev->phys = "wmi/input0";
dell_wmi_input_dev->id.bustype = BUS_HOST;
if (dell_new_hk_type) {
const struct key_entry *keymap = dell_wmi_prepare_new_keymap();
if (!keymap) {
err = -ENOMEM;
goto err_free_dev;
}
err = sparse_keymap_setup(dell_wmi_input_dev, keymap, NULL);
/*
* Sparse keymap library makes a copy of keymap so we
* don't need the original one that was allocated.
*/
kfree(keymap);
} else {
err = sparse_keymap_setup(dell_wmi_input_dev,
dell_wmi_legacy_keymap, NULL);
}
if (err)
goto err_free_dev;
err = input_register_device(dell_wmi_input_dev);
if (err)
goto err_free_keymap;
return 0;
err_free_keymap:
sparse_keymap_free(dell_wmi_input_dev);
err_free_dev:
input_free_device(dell_wmi_input_dev);
return err;
}
static void dell_wmi_input_destroy(void)
{
sparse_keymap_free(dell_wmi_input_dev);
input_unregister_device(dell_wmi_input_dev);
}
static void __init find_hk_type(const struct dmi_header *dm, void *dummy)
{
if (dm->type == 0xb2 && dm->length > 6) {
dell_new_hk_type = true;
dell_bios_hotkey_table =
container_of(dm, struct dell_bios_hotkey_table, header);
}
}
static int __init dell_wmi_init(void)
{
int err;
acpi_status status;
if (!wmi_has_guid(DELL_EVENT_GUID)) {
pr_warn("No known WMI GUID found\n");
return -ENODEV;
}
dmi_walk(find_hk_type, NULL);
acpi_video = acpi_video_backlight_support();
err = dell_wmi_input_setup();
if (err)
return err;
status = wmi_install_notify_handler(DELL_EVENT_GUID,
dell_wmi_notify, NULL);
if (ACPI_FAILURE(status)) {
dell_wmi_input_destroy();
pr_err("Unable to register notify handler - %d\n", status);
return -ENODEV;
}
return 0;
}
module_init(dell_wmi_init);
static void __exit dell_wmi_exit(void)
{
wmi_remove_notify_handler(DELL_EVENT_GUID);
dell_wmi_input_destroy();
}
module_exit(dell_wmi_exit);