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linux/drivers/usb/core/hub.c
Alan Stern 2425e9fe67 [PATCH] USB: Don't assume root-hub resume succeeds 
This patch (as614) makes a small change to the part of the hub driver
responsible for remote wakeup of root hubs.  When these wakeups occur
the driver is suspended, and in case the resume fails the driver should
remain suspended -- it shouldn't try to proceed with its normal
processing.

This will hardly ever matter in normal use, but it did crop up while I
was debugging a different problem.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-01-04 13:51:40 -08:00

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/*
* USB hub driver.
*
* (C) Copyright 1999 Linus Torvalds
* (C) Copyright 1999 Johannes Erdfelt
* (C) Copyright 1999 Gregory P. Smith
* (C) Copyright 2001 Brad Hards (bhards@bigpond.net.au)
*
*/
#include <linux/config.h>
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/completion.h>
#include <linux/sched.h>
#include <linux/list.h>
#include <linux/slab.h>
#include <linux/smp_lock.h>
#include <linux/ioctl.h>
#include <linux/usb.h>
#include <linux/usbdevice_fs.h>
#include <linux/kthread.h>
#include <asm/semaphore.h>
#include <asm/uaccess.h>
#include <asm/byteorder.h>
#include "usb.h"
#include "hcd.h"
#include "hub.h"
/* Protect struct usb_device->state and ->children members
* Note: Both are also protected by ->dev.sem, except that ->state can
* change to USB_STATE_NOTATTACHED even when the semaphore isn't held. */
static DEFINE_SPINLOCK(device_state_lock);
/* khubd's worklist and its lock */
static DEFINE_SPINLOCK(hub_event_lock);
static LIST_HEAD(hub_event_list); /* List of hubs needing servicing */
/* Wakes up khubd */
static DECLARE_WAIT_QUEUE_HEAD(khubd_wait);
static struct task_struct *khubd_task;
/* cycle leds on hubs that aren't blinking for attention */
static int blinkenlights = 0;
module_param (blinkenlights, bool, S_IRUGO);
MODULE_PARM_DESC (blinkenlights, "true to cycle leds on hubs");
/*
* As of 2.6.10 we introduce a new USB device initialization scheme which
* closely resembles the way Windows works. Hopefully it will be compatible
* with a wider range of devices than the old scheme. However some previously
* working devices may start giving rise to "device not accepting address"
* errors; if that happens the user can try the old scheme by adjusting the
* following module parameters.
*
* For maximum flexibility there are two boolean parameters to control the
* hub driver's behavior. On the first initialization attempt, if the
* "old_scheme_first" parameter is set then the old scheme will be used,
* otherwise the new scheme is used. If that fails and "use_both_schemes"
* is set, then the driver will make another attempt, using the other scheme.
*/
static int old_scheme_first = 0;
module_param(old_scheme_first, bool, S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(old_scheme_first,
"start with the old device initialization scheme");
static int use_both_schemes = 1;
module_param(use_both_schemes, bool, S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(use_both_schemes,
"try the other device initialization scheme if the "
"first one fails");
#ifdef DEBUG
static inline char *portspeed (int portstatus)
{
if (portstatus & (1 << USB_PORT_FEAT_HIGHSPEED))
return "480 Mb/s";
else if (portstatus & (1 << USB_PORT_FEAT_LOWSPEED))
return "1.5 Mb/s";
else
return "12 Mb/s";
}
#endif
/* Note that hdev or one of its children must be locked! */
static inline struct usb_hub *hdev_to_hub(struct usb_device *hdev)
{
return usb_get_intfdata(hdev->actconfig->interface[0]);
}
/* USB 2.0 spec Section 11.24.4.5 */
static int get_hub_descriptor(struct usb_device *hdev, void *data, int size)
{
int i, ret;
for (i = 0; i < 3; i++) {
ret = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
USB_REQ_GET_DESCRIPTOR, USB_DIR_IN | USB_RT_HUB,
USB_DT_HUB << 8, 0, data, size,
USB_CTRL_GET_TIMEOUT);
if (ret >= (USB_DT_HUB_NONVAR_SIZE + 2))
return ret;
}
return -EINVAL;
}
/*
* USB 2.0 spec Section 11.24.2.1
*/
static int clear_hub_feature(struct usb_device *hdev, int feature)
{
return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
USB_REQ_CLEAR_FEATURE, USB_RT_HUB, feature, 0, NULL, 0, 1000);
}
/*
* USB 2.0 spec Section 11.24.2.2
*/
static int clear_port_feature(struct usb_device *hdev, int port1, int feature)
{
return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
USB_REQ_CLEAR_FEATURE, USB_RT_PORT, feature, port1,
NULL, 0, 1000);
}
/*
* USB 2.0 spec Section 11.24.2.13
*/
static int set_port_feature(struct usb_device *hdev, int port1, int feature)
{
return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
USB_REQ_SET_FEATURE, USB_RT_PORT, feature, port1,
NULL, 0, 1000);
}
/*
* USB 2.0 spec Section 11.24.2.7.1.10 and table 11-7
* for info about using port indicators
*/
static void set_port_led(
struct usb_hub *hub,
int port1,
int selector
)
{
int status = set_port_feature(hub->hdev, (selector << 8) | port1,
USB_PORT_FEAT_INDICATOR);
if (status < 0)
dev_dbg (hub->intfdev,
"port %d indicator %s status %d\n",
port1,
({ char *s; switch (selector) {
case HUB_LED_AMBER: s = "amber"; break;
case HUB_LED_GREEN: s = "green"; break;
case HUB_LED_OFF: s = "off"; break;
case HUB_LED_AUTO: s = "auto"; break;
default: s = "??"; break;
}; s; }),
status);
}
#define LED_CYCLE_PERIOD ((2*HZ)/3)
static void led_work (void *__hub)
{
struct usb_hub *hub = __hub;
struct usb_device *hdev = hub->hdev;
unsigned i;
unsigned changed = 0;
int cursor = -1;
if (hdev->state != USB_STATE_CONFIGURED || hub->quiescing)
return;
for (i = 0; i < hub->descriptor->bNbrPorts; i++) {
unsigned selector, mode;
/* 30%-50% duty cycle */
switch (hub->indicator[i]) {
/* cycle marker */
case INDICATOR_CYCLE:
cursor = i;
selector = HUB_LED_AUTO;
mode = INDICATOR_AUTO;
break;
/* blinking green = sw attention */
case INDICATOR_GREEN_BLINK:
selector = HUB_LED_GREEN;
mode = INDICATOR_GREEN_BLINK_OFF;
break;
case INDICATOR_GREEN_BLINK_OFF:
selector = HUB_LED_OFF;
mode = INDICATOR_GREEN_BLINK;
break;
/* blinking amber = hw attention */
case INDICATOR_AMBER_BLINK:
selector = HUB_LED_AMBER;
mode = INDICATOR_AMBER_BLINK_OFF;
break;
case INDICATOR_AMBER_BLINK_OFF:
selector = HUB_LED_OFF;
mode = INDICATOR_AMBER_BLINK;
break;
/* blink green/amber = reserved */
case INDICATOR_ALT_BLINK:
selector = HUB_LED_GREEN;
mode = INDICATOR_ALT_BLINK_OFF;
break;
case INDICATOR_ALT_BLINK_OFF:
selector = HUB_LED_AMBER;
mode = INDICATOR_ALT_BLINK;
break;
default:
continue;
}
if (selector != HUB_LED_AUTO)
changed = 1;
set_port_led(hub, i + 1, selector);
hub->indicator[i] = mode;
}
if (!changed && blinkenlights) {
cursor++;
cursor %= hub->descriptor->bNbrPorts;
set_port_led(hub, cursor + 1, HUB_LED_GREEN);
hub->indicator[cursor] = INDICATOR_CYCLE;
changed++;
}
if (changed)
schedule_delayed_work(&hub->leds, LED_CYCLE_PERIOD);
}
/* use a short timeout for hub/port status fetches */
#define USB_STS_TIMEOUT 1000
#define USB_STS_RETRIES 5
/*
* USB 2.0 spec Section 11.24.2.6
*/
static int get_hub_status(struct usb_device *hdev,
struct usb_hub_status *data)
{
int i, status = -ETIMEDOUT;
for (i = 0; i < USB_STS_RETRIES && status == -ETIMEDOUT; i++) {
status = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_HUB, 0, 0,
data, sizeof(*data), USB_STS_TIMEOUT);
}
return status;
}
/*
* USB 2.0 spec Section 11.24.2.7
*/
static int get_port_status(struct usb_device *hdev, int port1,
struct usb_port_status *data)
{
int i, status = -ETIMEDOUT;
for (i = 0; i < USB_STS_RETRIES && status == -ETIMEDOUT; i++) {
status = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_PORT, 0, port1,
data, sizeof(*data), USB_STS_TIMEOUT);
}
return status;
}
static void kick_khubd(struct usb_hub *hub)
{
unsigned long flags;
spin_lock_irqsave(&hub_event_lock, flags);
if (list_empty(&hub->event_list)) {
list_add_tail(&hub->event_list, &hub_event_list);
wake_up(&khubd_wait);
}
spin_unlock_irqrestore(&hub_event_lock, flags);
}
void usb_kick_khubd(struct usb_device *hdev)
{
kick_khubd(hdev_to_hub(hdev));
}
/* completion function, fires on port status changes and various faults */
static void hub_irq(struct urb *urb, struct pt_regs *regs)
{
struct usb_hub *hub = (struct usb_hub *)urb->context;
int status;
int i;
unsigned long bits;
switch (urb->status) {
case -ENOENT: /* synchronous unlink */
case -ECONNRESET: /* async unlink */
case -ESHUTDOWN: /* hardware going away */
return;
default: /* presumably an error */
/* Cause a hub reset after 10 consecutive errors */
dev_dbg (hub->intfdev, "transfer --> %d\n", urb->status);
if ((++hub->nerrors < 10) || hub->error)
goto resubmit;
hub->error = urb->status;
/* FALL THROUGH */
/* let khubd handle things */
case 0: /* we got data: port status changed */
bits = 0;
for (i = 0; i < urb->actual_length; ++i)
bits |= ((unsigned long) ((*hub->buffer)[i]))
<< (i*8);
hub->event_bits[0] = bits;
break;
}
hub->nerrors = 0;
/* Something happened, let khubd figure it out */
kick_khubd(hub);
resubmit:
if (hub->quiescing)
return;
if ((status = usb_submit_urb (hub->urb, GFP_ATOMIC)) != 0
&& status != -ENODEV && status != -EPERM)
dev_err (hub->intfdev, "resubmit --> %d\n", status);
}
/* USB 2.0 spec Section 11.24.2.3 */
static inline int
hub_clear_tt_buffer (struct usb_device *hdev, u16 devinfo, u16 tt)
{
return usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
HUB_CLEAR_TT_BUFFER, USB_RT_PORT, devinfo,
tt, NULL, 0, 1000);
}
/*
* enumeration blocks khubd for a long time. we use keventd instead, since
* long blocking there is the exception, not the rule. accordingly, HCDs
* talking to TTs must queue control transfers (not just bulk and iso), so
* both can talk to the same hub concurrently.
*/
static void hub_tt_kevent (void *arg)
{
struct usb_hub *hub = arg;
unsigned long flags;
spin_lock_irqsave (&hub->tt.lock, flags);
while (!list_empty (&hub->tt.clear_list)) {
struct list_head *temp;
struct usb_tt_clear *clear;
struct usb_device *hdev = hub->hdev;
int status;
temp = hub->tt.clear_list.next;
clear = list_entry (temp, struct usb_tt_clear, clear_list);
list_del (&clear->clear_list);
/* drop lock so HCD can concurrently report other TT errors */
spin_unlock_irqrestore (&hub->tt.lock, flags);
status = hub_clear_tt_buffer (hdev, clear->devinfo, clear->tt);
spin_lock_irqsave (&hub->tt.lock, flags);
if (status)
dev_err (&hdev->dev,
"clear tt %d (%04x) error %d\n",
clear->tt, clear->devinfo, status);
kfree(clear);
}
spin_unlock_irqrestore (&hub->tt.lock, flags);
}
/**
* usb_hub_tt_clear_buffer - clear control/bulk TT state in high speed hub
* @udev: the device whose split transaction failed
* @pipe: identifies the endpoint of the failed transaction
*
* High speed HCDs use this to tell the hub driver that some split control or
* bulk transaction failed in a way that requires clearing internal state of
* a transaction translator. This is normally detected (and reported) from
* interrupt context.
*
* It may not be possible for that hub to handle additional full (or low)
* speed transactions until that state is fully cleared out.
*/
void usb_hub_tt_clear_buffer (struct usb_device *udev, int pipe)
{
struct usb_tt *tt = udev->tt;
unsigned long flags;
struct usb_tt_clear *clear;
/* we've got to cope with an arbitrary number of pending TT clears,
* since each TT has "at least two" buffers that can need it (and
* there can be many TTs per hub). even if they're uncommon.
*/
if ((clear = kmalloc (sizeof *clear, SLAB_ATOMIC)) == NULL) {
dev_err (&udev->dev, "can't save CLEAR_TT_BUFFER state\n");
/* FIXME recover somehow ... RESET_TT? */
return;
}
/* info that CLEAR_TT_BUFFER needs */
clear->tt = tt->multi ? udev->ttport : 1;
clear->devinfo = usb_pipeendpoint (pipe);
clear->devinfo |= udev->devnum << 4;
clear->devinfo |= usb_pipecontrol (pipe)
? (USB_ENDPOINT_XFER_CONTROL << 11)
: (USB_ENDPOINT_XFER_BULK << 11);
if (usb_pipein (pipe))
clear->devinfo |= 1 << 15;
/* tell keventd to clear state for this TT */
spin_lock_irqsave (&tt->lock, flags);
list_add_tail (&clear->clear_list, &tt->clear_list);
schedule_work (&tt->kevent);
spin_unlock_irqrestore (&tt->lock, flags);
}
static void hub_power_on(struct usb_hub *hub)
{
int port1;
unsigned pgood_delay = hub->descriptor->bPwrOn2PwrGood * 2;
u16 wHubCharacteristics = le16_to_cpu(hub->descriptor->wHubCharacteristics);
/* if hub supports power switching, enable power on each port */
if ((wHubCharacteristics & HUB_CHAR_LPSM) < 2) {
dev_dbg(hub->intfdev, "enabling power on all ports\n");
for (port1 = 1; port1 <= hub->descriptor->bNbrPorts; port1++)
set_port_feature(hub->hdev, port1,
USB_PORT_FEAT_POWER);
}
/* Wait at least 100 msec for power to become stable */
msleep(max(pgood_delay, (unsigned) 100));
}
static inline void __hub_quiesce(struct usb_hub *hub)
{
/* (nonblocking) khubd and related activity won't re-trigger */
hub->quiescing = 1;
hub->activating = 0;
hub->resume_root_hub = 0;
}
static void hub_quiesce(struct usb_hub *hub)
{
/* (blocking) stop khubd and related activity */
__hub_quiesce(hub);
usb_kill_urb(hub->urb);
if (hub->has_indicators)
cancel_delayed_work(&hub->leds);
if (hub->has_indicators || hub->tt.hub)
flush_scheduled_work();
}
static void hub_activate(struct usb_hub *hub)
{
int status;
hub->quiescing = 0;
hub->activating = 1;
hub->resume_root_hub = 0;
status = usb_submit_urb(hub->urb, GFP_NOIO);
if (status < 0)
dev_err(hub->intfdev, "activate --> %d\n", status);
if (hub->has_indicators && blinkenlights)
schedule_delayed_work(&hub->leds, LED_CYCLE_PERIOD);
/* scan all ports ASAP */
kick_khubd(hub);
}
static int hub_hub_status(struct usb_hub *hub,
u16 *status, u16 *change)
{
int ret;
ret = get_hub_status(hub->hdev, &hub->status->hub);
if (ret < 0)
dev_err (hub->intfdev,
"%s failed (err = %d)\n", __FUNCTION__, ret);
else {
*status = le16_to_cpu(hub->status->hub.wHubStatus);
*change = le16_to_cpu(hub->status->hub.wHubChange);
ret = 0;
}
return ret;
}
static int hub_port_disable(struct usb_hub *hub, int port1, int set_state)
{
struct usb_device *hdev = hub->hdev;
int ret;
if (hdev->children[port1-1] && set_state) {
usb_set_device_state(hdev->children[port1-1],
USB_STATE_NOTATTACHED);
}
ret = clear_port_feature(hdev, port1, USB_PORT_FEAT_ENABLE);
if (ret)
dev_err(hub->intfdev, "cannot disable port %d (err = %d)\n",
port1, ret);
return ret;
}
/* caller has locked the hub device */
static void hub_pre_reset(struct usb_hub *hub, int disable_ports)
{
struct usb_device *hdev = hub->hdev;
int port1;
for (port1 = 1; port1 <= hdev->maxchild; ++port1) {
if (hdev->children[port1 - 1]) {
usb_disconnect(&hdev->children[port1 - 1]);
if (disable_ports)
hub_port_disable(hub, port1, 0);
}
}
hub_quiesce(hub);
}
/* caller has locked the hub device */
static void hub_post_reset(struct usb_hub *hub)
{
hub_activate(hub);
hub_power_on(hub);
}
static int hub_configure(struct usb_hub *hub,
struct usb_endpoint_descriptor *endpoint)
{
struct usb_device *hdev = hub->hdev;
struct device *hub_dev = hub->intfdev;
u16 hubstatus, hubchange;
u16 wHubCharacteristics;
unsigned int pipe;
int maxp, ret;
char *message;
hub->buffer = usb_buffer_alloc(hdev, sizeof(*hub->buffer), GFP_KERNEL,
&hub->buffer_dma);
if (!hub->buffer) {
message = "can't allocate hub irq buffer";
ret = -ENOMEM;
goto fail;
}
hub->status = kmalloc(sizeof(*hub->status), GFP_KERNEL);
if (!hub->status) {
message = "can't kmalloc hub status buffer";
ret = -ENOMEM;
goto fail;
}
hub->descriptor = kmalloc(sizeof(*hub->descriptor), GFP_KERNEL);
if (!hub->descriptor) {
message = "can't kmalloc hub descriptor";
ret = -ENOMEM;
goto fail;
}
/* Request the entire hub descriptor.
* hub->descriptor can handle USB_MAXCHILDREN ports,
* but the hub can/will return fewer bytes here.
*/
ret = get_hub_descriptor(hdev, hub->descriptor,
sizeof(*hub->descriptor));
if (ret < 0) {
message = "can't read hub descriptor";
goto fail;
} else if (hub->descriptor->bNbrPorts > USB_MAXCHILDREN) {
message = "hub has too many ports!";
ret = -ENODEV;
goto fail;
}
hdev->maxchild = hub->descriptor->bNbrPorts;
dev_info (hub_dev, "%d port%s detected\n", hdev->maxchild,
(hdev->maxchild == 1) ? "" : "s");
wHubCharacteristics = le16_to_cpu(hub->descriptor->wHubCharacteristics);
if (wHubCharacteristics & HUB_CHAR_COMPOUND) {
int i;
char portstr [USB_MAXCHILDREN + 1];
for (i = 0; i < hdev->maxchild; i++)
portstr[i] = hub->descriptor->DeviceRemovable
[((i + 1) / 8)] & (1 << ((i + 1) % 8))
? 'F' : 'R';
portstr[hdev->maxchild] = 0;
dev_dbg(hub_dev, "compound device; port removable status: %s\n", portstr);
} else
dev_dbg(hub_dev, "standalone hub\n");
switch (wHubCharacteristics & HUB_CHAR_LPSM) {
case 0x00:
dev_dbg(hub_dev, "ganged power switching\n");
break;
case 0x01:
dev_dbg(hub_dev, "individual port power switching\n");
break;
case 0x02:
case 0x03:
dev_dbg(hub_dev, "no power switching (usb 1.0)\n");
break;
}
switch (wHubCharacteristics & HUB_CHAR_OCPM) {
case 0x00:
dev_dbg(hub_dev, "global over-current protection\n");
break;
case 0x08:
dev_dbg(hub_dev, "individual port over-current protection\n");
break;
case 0x10:
case 0x18:
dev_dbg(hub_dev, "no over-current protection\n");
break;
}
spin_lock_init (&hub->tt.lock);
INIT_LIST_HEAD (&hub->tt.clear_list);
INIT_WORK (&hub->tt.kevent, hub_tt_kevent, hub);
switch (hdev->descriptor.bDeviceProtocol) {
case 0:
break;
case 1:
dev_dbg(hub_dev, "Single TT\n");
hub->tt.hub = hdev;
break;
case 2:
ret = usb_set_interface(hdev, 0, 1);
if (ret == 0) {
dev_dbg(hub_dev, "TT per port\n");
hub->tt.multi = 1;
} else
dev_err(hub_dev, "Using single TT (err %d)\n",
ret);
hub->tt.hub = hdev;
break;
default:
dev_dbg(hub_dev, "Unrecognized hub protocol %d\n",
hdev->descriptor.bDeviceProtocol);
break;
}
/* Note 8 FS bit times == (8 bits / 12000000 bps) ~= 666ns */
switch (wHubCharacteristics & HUB_CHAR_TTTT) {
case HUB_TTTT_8_BITS:
if (hdev->descriptor.bDeviceProtocol != 0) {
hub->tt.think_time = 666;
dev_dbg(hub_dev, "TT requires at most %d "
"FS bit times (%d ns)\n",
8, hub->tt.think_time);
}
break;
case HUB_TTTT_16_BITS:
hub->tt.think_time = 666 * 2;
dev_dbg(hub_dev, "TT requires at most %d "
"FS bit times (%d ns)\n",
16, hub->tt.think_time);
break;
case HUB_TTTT_24_BITS:
hub->tt.think_time = 666 * 3;
dev_dbg(hub_dev, "TT requires at most %d "
"FS bit times (%d ns)\n",
24, hub->tt.think_time);
break;
case HUB_TTTT_32_BITS:
hub->tt.think_time = 666 * 4;
dev_dbg(hub_dev, "TT requires at most %d "
"FS bit times (%d ns)\n",
32, hub->tt.think_time);
break;
}
/* probe() zeroes hub->indicator[] */
if (wHubCharacteristics & HUB_CHAR_PORTIND) {
hub->has_indicators = 1;
dev_dbg(hub_dev, "Port indicators are supported\n");
}
dev_dbg(hub_dev, "power on to power good time: %dms\n",
hub->descriptor->bPwrOn2PwrGood * 2);
/* power budgeting mostly matters with bus-powered hubs,
* and battery-powered root hubs (may provide just 8 mA).
*/
ret = usb_get_status(hdev, USB_RECIP_DEVICE, 0, &hubstatus);
if (ret < 2) {
message = "can't get hub status";
goto fail;
}
le16_to_cpus(&hubstatus);
if (hdev == hdev->bus->root_hub) {
if (hdev->bus_mA == 0 || hdev->bus_mA >= 500)
hub->mA_per_port = 500;
else {
hub->mA_per_port = hdev->bus_mA;
hub->limited_power = 1;
}
} else if ((hubstatus & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
dev_dbg(hub_dev, "hub controller current requirement: %dmA\n",
hub->descriptor->bHubContrCurrent);
hub->limited_power = 1;
if (hdev->maxchild > 0) {
int remaining = hdev->bus_mA -
hub->descriptor->bHubContrCurrent;
if (remaining < hdev->maxchild * 100)
dev_warn(hub_dev,
"insufficient power available "
"to use all downstream ports\n");
hub->mA_per_port = 100; /* 7.2.1.1 */
}
} else { /* Self-powered external hub */
/* FIXME: What about battery-powered external hubs that
* provide less current per port? */
hub->mA_per_port = 500;
}
if (hub->mA_per_port < 500)
dev_dbg(hub_dev, "%umA bus power budget for each child\n",
hub->mA_per_port);
ret = hub_hub_status(hub, &hubstatus, &hubchange);
if (ret < 0) {
message = "can't get hub status";
goto fail;
}
/* local power status reports aren't always correct */
if (hdev->actconfig->desc.bmAttributes & USB_CONFIG_ATT_SELFPOWER)
dev_dbg(hub_dev, "local power source is %s\n",
(hubstatus & HUB_STATUS_LOCAL_POWER)
? "lost (inactive)" : "good");
if ((wHubCharacteristics & HUB_CHAR_OCPM) == 0)
dev_dbg(hub_dev, "%sover-current condition exists\n",
(hubstatus & HUB_STATUS_OVERCURRENT) ? "" : "no ");
/* set up the interrupt endpoint */
pipe = usb_rcvintpipe(hdev, endpoint->bEndpointAddress);
maxp = usb_maxpacket(hdev, pipe, usb_pipeout(pipe));
if (maxp > sizeof(*hub->buffer))
maxp = sizeof(*hub->buffer);
hub->urb = usb_alloc_urb(0, GFP_KERNEL);
if (!hub->urb) {
message = "couldn't allocate interrupt urb";
ret = -ENOMEM;
goto fail;
}
usb_fill_int_urb(hub->urb, hdev, pipe, *hub->buffer, maxp, hub_irq,
hub, endpoint->bInterval);
hub->urb->transfer_dma = hub->buffer_dma;
hub->urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
/* maybe cycle the hub leds */
if (hub->has_indicators && blinkenlights)
hub->indicator [0] = INDICATOR_CYCLE;
hub_power_on(hub);
hub_activate(hub);
return 0;
fail:
dev_err (hub_dev, "config failed, %s (err %d)\n",
message, ret);
/* hub_disconnect() frees urb and descriptor */
return ret;
}
static unsigned highspeed_hubs;
static void hub_disconnect(struct usb_interface *intf)
{
struct usb_hub *hub = usb_get_intfdata (intf);
struct usb_device *hdev;
usb_set_intfdata (intf, NULL);
hdev = hub->hdev;
if (hdev->speed == USB_SPEED_HIGH)
highspeed_hubs--;
/* Disconnect all children and quiesce the hub */
hub_pre_reset(hub, 1);
usb_free_urb(hub->urb);
hub->urb = NULL;
spin_lock_irq(&hub_event_lock);
list_del_init(&hub->event_list);
spin_unlock_irq(&hub_event_lock);
kfree(hub->descriptor);
hub->descriptor = NULL;
kfree(hub->status);
hub->status = NULL;
if (hub->buffer) {
usb_buffer_free(hdev, sizeof(*hub->buffer), hub->buffer,
hub->buffer_dma);
hub->buffer = NULL;
}
kfree(hub);
}
static int hub_probe(struct usb_interface *intf, const struct usb_device_id *id)
{
struct usb_host_interface *desc;
struct usb_endpoint_descriptor *endpoint;
struct usb_device *hdev;
struct usb_hub *hub;
desc = intf->cur_altsetting;
hdev = interface_to_usbdev(intf);
/* Some hubs have a subclass of 1, which AFAICT according to the */
/* specs is not defined, but it works */
if ((desc->desc.bInterfaceSubClass != 0) &&
(desc->desc.bInterfaceSubClass != 1)) {
descriptor_error:
dev_err (&intf->dev, "bad descriptor, ignoring hub\n");
return -EIO;
}
/* Multiple endpoints? What kind of mutant ninja-hub is this? */
if (desc->desc.bNumEndpoints != 1)
goto descriptor_error;
endpoint = &desc->endpoint[0].desc;
/* Output endpoint? Curiouser and curiouser.. */
if (!(endpoint->bEndpointAddress & USB_DIR_IN))
goto descriptor_error;
/* If it's not an interrupt endpoint, we'd better punt! */
if ((endpoint->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK)
!= USB_ENDPOINT_XFER_INT)
goto descriptor_error;
/* We found a hub */
dev_info (&intf->dev, "USB hub found\n");
hub = kzalloc(sizeof(*hub), GFP_KERNEL);
if (!hub) {
dev_dbg (&intf->dev, "couldn't kmalloc hub struct\n");
return -ENOMEM;
}
INIT_LIST_HEAD(&hub->event_list);
hub->intfdev = &intf->dev;
hub->hdev = hdev;
INIT_WORK(&hub->leds, led_work, hub);
usb_set_intfdata (intf, hub);
if (hdev->speed == USB_SPEED_HIGH)
highspeed_hubs++;
if (hub_configure(hub, endpoint) >= 0)
return 0;
hub_disconnect (intf);
return -ENODEV;
}
static int
hub_ioctl(struct usb_interface *intf, unsigned int code, void *user_data)
{
struct usb_device *hdev = interface_to_usbdev (intf);
/* assert ifno == 0 (part of hub spec) */
switch (code) {
case USBDEVFS_HUB_PORTINFO: {
struct usbdevfs_hub_portinfo *info = user_data;
int i;
spin_lock_irq(&device_state_lock);
if (hdev->devnum <= 0)
info->nports = 0;
else {
info->nports = hdev->maxchild;
for (i = 0; i < info->nports; i++) {
if (hdev->children[i] == NULL)
info->port[i] = 0;
else
info->port[i] =
hdev->children[i]->devnum;
}
}
spin_unlock_irq(&device_state_lock);
return info->nports + 1;
}
default:
return -ENOSYS;
}
}
/* grab device/port lock, returning index of that port (zero based).
* protects the upstream link used by this device from concurrent
* tree operations like suspend, resume, reset, and disconnect, which
* apply to everything downstream of a given port.
*/
static int locktree(struct usb_device *udev)
{
int t;
struct usb_device *hdev;
if (!udev)
return -ENODEV;
/* root hub is always the first lock in the series */
hdev = udev->parent;
if (!hdev) {
usb_lock_device(udev);
return 0;
}
/* on the path from root to us, lock everything from
* top down, dropping parent locks when not needed
*/
t = locktree(hdev);
if (t < 0)
return t;
/* everything is fail-fast once disconnect
* processing starts
*/
if (udev->state == USB_STATE_NOTATTACHED) {
usb_unlock_device(hdev);
return -ENODEV;
}
/* when everyone grabs locks top->bottom,
* non-overlapping work may be concurrent
*/
usb_lock_device(udev);
usb_unlock_device(hdev);
return udev->portnum;
}
static void recursively_mark_NOTATTACHED(struct usb_device *udev)
{
int i;
for (i = 0; i < udev->maxchild; ++i) {
if (udev->children[i])
recursively_mark_NOTATTACHED(udev->children[i]);
}
udev->state = USB_STATE_NOTATTACHED;
}
/**
* usb_set_device_state - change a device's current state (usbcore, hcds)
* @udev: pointer to device whose state should be changed
* @new_state: new state value to be stored
*
* udev->state is _not_ fully protected by the device lock. Although
* most transitions are made only while holding the lock, the state can
* can change to USB_STATE_NOTATTACHED at almost any time. This
* is so that devices can be marked as disconnected as soon as possible,
* without having to wait for any semaphores to be released. As a result,
* all changes to any device's state must be protected by the
* device_state_lock spinlock.
*
* Once a device has been added to the device tree, all changes to its state
* should be made using this routine. The state should _not_ be set directly.
*
* If udev->state is already USB_STATE_NOTATTACHED then no change is made.
* Otherwise udev->state is set to new_state, and if new_state is
* USB_STATE_NOTATTACHED then all of udev's descendants' states are also set
* to USB_STATE_NOTATTACHED.
*/
void usb_set_device_state(struct usb_device *udev,
enum usb_device_state new_state)
{
unsigned long flags;
spin_lock_irqsave(&device_state_lock, flags);
if (udev->state == USB_STATE_NOTATTACHED)
; /* do nothing */
else if (new_state != USB_STATE_NOTATTACHED) {
udev->state = new_state;
if (new_state == USB_STATE_CONFIGURED)
device_init_wakeup(&udev->dev,
(udev->actconfig->desc.bmAttributes
& USB_CONFIG_ATT_WAKEUP));
else if (new_state != USB_STATE_SUSPENDED)
device_init_wakeup(&udev->dev, 0);
} else
recursively_mark_NOTATTACHED(udev);
spin_unlock_irqrestore(&device_state_lock, flags);
}
EXPORT_SYMBOL(usb_set_device_state);
#ifdef CONFIG_PM
/**
* usb_root_hub_lost_power - called by HCD if the root hub lost Vbus power
* @rhdev: struct usb_device for the root hub
*
* The USB host controller driver calls this function when its root hub
* is resumed and Vbus power has been interrupted or the controller
* has been reset. The routine marks all the children of the root hub
* as NOTATTACHED and marks logical connect-change events on their ports.
*/
void usb_root_hub_lost_power(struct usb_device *rhdev)
{
struct usb_hub *hub;
int port1;
unsigned long flags;
dev_warn(&rhdev->dev, "root hub lost power or was reset\n");
spin_lock_irqsave(&device_state_lock, flags);
hub = hdev_to_hub(rhdev);
for (port1 = 1; port1 <= rhdev->maxchild; ++port1) {
if (rhdev->children[port1 - 1]) {
recursively_mark_NOTATTACHED(
rhdev->children[port1 - 1]);
set_bit(port1, hub->change_bits);
}
}
spin_unlock_irqrestore(&device_state_lock, flags);
}
EXPORT_SYMBOL_GPL(usb_root_hub_lost_power);
#endif
static void choose_address(struct usb_device *udev)
{
int devnum;
struct usb_bus *bus = udev->bus;
/* If khubd ever becomes multithreaded, this will need a lock */
/* Try to allocate the next devnum beginning at bus->devnum_next. */
devnum = find_next_zero_bit(bus->devmap.devicemap, 128,
bus->devnum_next);
if (devnum >= 128)
devnum = find_next_zero_bit(bus->devmap.devicemap, 128, 1);
bus->devnum_next = ( devnum >= 127 ? 1 : devnum + 1);
if (devnum < 128) {
set_bit(devnum, bus->devmap.devicemap);
udev->devnum = devnum;
}
}
static void release_address(struct usb_device *udev)
{
if (udev->devnum > 0) {
clear_bit(udev->devnum, udev->bus->devmap.devicemap);
udev->devnum = -1;
}
}
/**
* usb_disconnect - disconnect a device (usbcore-internal)
* @pdev: pointer to device being disconnected
* Context: !in_interrupt ()
*
* Something got disconnected. Get rid of it and all of its children.
*
* If *pdev is a normal device then the parent hub must already be locked.
* If *pdev is a root hub then this routine will acquire the
* usb_bus_list_lock on behalf of the caller.
*
* Only hub drivers (including virtual root hub drivers for host
* controllers) should ever call this.
*
* This call is synchronous, and may not be used in an interrupt context.
*/
void usb_disconnect(struct usb_device **pdev)
{
struct usb_device *udev = *pdev;
int i;
if (!udev) {
pr_debug ("%s nodev\n", __FUNCTION__);
return;
}
/* mark the device as inactive, so any further urb submissions for
* this device (and any of its children) will fail immediately.
* this quiesces everyting except pending urbs.
*/
usb_set_device_state(udev, USB_STATE_NOTATTACHED);
dev_info (&udev->dev, "USB disconnect, address %d\n", udev->devnum);
usb_lock_device(udev);
/* Free up all the children before we remove this device */
for (i = 0; i < USB_MAXCHILDREN; i++) {
if (udev->children[i])
usb_disconnect(&udev->children[i]);
}
/* deallocate hcd/hardware state ... nuking all pending urbs and
* cleaning up all state associated with the current configuration
* so that the hardware is now fully quiesced.
*/
usb_disable_device(udev, 0);
usb_notify_remove_device(udev);
/* Free the device number, remove the /proc/bus/usb entry and
* the sysfs attributes, and delete the parent's children[]
* (or root_hub) pointer.
*/
dev_dbg (&udev->dev, "unregistering device\n");
release_address(udev);
usb_remove_sysfs_dev_files(udev);
/* Avoid races with recursively_mark_NOTATTACHED() */
spin_lock_irq(&device_state_lock);
*pdev = NULL;
spin_unlock_irq(&device_state_lock);
usb_unlock_device(udev);
device_unregister(&udev->dev);
}
static inline const char *plural(int n)
{
return (n == 1 ? "" : "s");
}
static int choose_configuration(struct usb_device *udev)
{
int i;
u16 devstatus;
int bus_powered;
int num_configs;
struct usb_host_config *c, *best;
/* If this fails, assume the device is bus-powered */
devstatus = 0;
usb_get_status(udev, USB_RECIP_DEVICE, 0, &devstatus);
le16_to_cpus(&devstatus);
bus_powered = ((devstatus & (1 << USB_DEVICE_SELF_POWERED)) == 0);
dev_dbg(&udev->dev, "device is %s-powered\n",
bus_powered ? "bus" : "self");
best = NULL;
c = udev->config;
num_configs = udev->descriptor.bNumConfigurations;
for (i = 0; i < num_configs; (i++, c++)) {
struct usb_interface_descriptor *desc =
&c->intf_cache[0]->altsetting->desc;
/*
* HP's USB bus-powered keyboard has only one configuration
* and it claims to be self-powered; other devices may have
* similar errors in their descriptors. If the next test
* were allowed to execute, such configurations would always
* be rejected and the devices would not work as expected.
*/
#if 0
/* Rule out self-powered configs for a bus-powered device */
if (bus_powered && (c->desc.bmAttributes &
USB_CONFIG_ATT_SELFPOWER))
continue;
#endif
/*
* The next test may not be as effective as it should be.
* Some hubs have errors in their descriptor, claiming
* to be self-powered when they are really bus-powered.
* We will overestimate the amount of current such hubs
* make available for each port.
*
* This is a fairly benign sort of failure. It won't
* cause us to reject configurations that we should have
* accepted.
*/
/* Rule out configs that draw too much bus current */
if (c->desc.bMaxPower * 2 > udev->bus_mA)
continue;
/* If the first config's first interface is COMM/2/0xff
* (MSFT RNDIS), rule it out unless Linux has host-side
* RNDIS support. */
if (i == 0 && desc->bInterfaceClass == USB_CLASS_COMM
&& desc->bInterfaceSubClass == 2
&& desc->bInterfaceProtocol == 0xff) {
#ifndef CONFIG_USB_NET_RNDIS
continue;
#else
best = c;
#endif
}
/* From the remaining configs, choose the first one whose
* first interface is for a non-vendor-specific class.
* Reason: Linux is more likely to have a class driver
* than a vendor-specific driver. */
else if (udev->descriptor.bDeviceClass !=
USB_CLASS_VENDOR_SPEC &&
desc->bInterfaceClass !=
USB_CLASS_VENDOR_SPEC) {
best = c;
break;
}
/* If all the remaining configs are vendor-specific,
* choose the first one. */
else if (!best)
best = c;
}
if (best) {
i = best->desc.bConfigurationValue;
dev_info(&udev->dev,
"configuration #%d chosen from %d choice%s\n",
i, num_configs, plural(num_configs));
} else {
i = -1;
dev_warn(&udev->dev,
"no configuration chosen from %d choice%s\n",
num_configs, plural(num_configs));
}
return i;
}
#ifdef DEBUG
static void show_string(struct usb_device *udev, char *id, char *string)
{
if (!string)
return;
dev_printk(KERN_INFO, &udev->dev, "%s: %s\n", id, string);
}
#else
static inline void show_string(struct usb_device *udev, char *id, char *string)
{}
#endif
#ifdef CONFIG_USB_OTG
#include "otg_whitelist.h"
#endif
/**
* usb_new_device - perform initial device setup (usbcore-internal)
* @udev: newly addressed device (in ADDRESS state)
*
* This is called with devices which have been enumerated, but not yet
* configured. The device descriptor is available, but not descriptors
* for any device configuration. The caller must have locked either
* the parent hub (if udev is a normal device) or else the
* usb_bus_list_lock (if udev is a root hub). The parent's pointer to
* udev has already been installed, but udev is not yet visible through
* sysfs or other filesystem code.
*
* Returns 0 for success (device is configured and listed, with its
* interfaces, in sysfs); else a negative errno value.
*
* This call is synchronous, and may not be used in an interrupt context.
*
* Only the hub driver or root-hub registrar should ever call this.
*/
int usb_new_device(struct usb_device *udev)
{
int err;
int c;
err = usb_get_configuration(udev);
if (err < 0) {
dev_err(&udev->dev, "can't read configurations, error %d\n",
err);
goto fail;
}
/* read the standard strings and cache them if present */
udev->product = usb_cache_string(udev, udev->descriptor.iProduct);
udev->manufacturer = usb_cache_string(udev,
udev->descriptor.iManufacturer);
udev->serial = usb_cache_string(udev, udev->descriptor.iSerialNumber);
/* Tell the world! */
dev_dbg(&udev->dev, "new device strings: Mfr=%d, Product=%d, "
"SerialNumber=%d\n",
udev->descriptor.iManufacturer,
udev->descriptor.iProduct,
udev->descriptor.iSerialNumber);
show_string(udev, "Product", udev->product);
show_string(udev, "Manufacturer", udev->manufacturer);
show_string(udev, "SerialNumber", udev->serial);
#ifdef CONFIG_USB_OTG
/*
* OTG-aware devices on OTG-capable root hubs may be able to use SRP,
* to wake us after we've powered off VBUS; and HNP, switching roles
* "host" to "peripheral". The OTG descriptor helps figure this out.
*/
if (!udev->bus->is_b_host
&& udev->config
&& udev->parent == udev->bus->root_hub) {
struct usb_otg_descriptor *desc = 0;
struct usb_bus *bus = udev->bus;
/* descriptor may appear anywhere in config */
if (__usb_get_extra_descriptor (udev->rawdescriptors[0],
le16_to_cpu(udev->config[0].desc.wTotalLength),
USB_DT_OTG, (void **) &desc) == 0) {
if (desc->bmAttributes & USB_OTG_HNP) {
unsigned port1 = udev->portnum;
struct usb_device *root = udev->parent;
dev_info(&udev->dev,
"Dual-Role OTG device on %sHNP port\n",
(port1 == bus->otg_port)
? "" : "non-");
/* enable HNP before suspend, it's simpler */
if (port1 == bus->otg_port)
bus->b_hnp_enable = 1;
err = usb_control_msg(udev,
usb_sndctrlpipe(udev, 0),
USB_REQ_SET_FEATURE, 0,
bus->b_hnp_enable
? USB_DEVICE_B_HNP_ENABLE
: USB_DEVICE_A_ALT_HNP_SUPPORT,
0, NULL, 0, USB_CTRL_SET_TIMEOUT);
if (err < 0) {
/* OTG MESSAGE: report errors here,
* customize to match your product.
*/
dev_info(&udev->dev,
"can't set HNP mode; %d\n",
err);
bus->b_hnp_enable = 0;
}
}
}
}
if (!is_targeted(udev)) {
/* Maybe it can talk to us, though we can't talk to it.
* (Includes HNP test device.)
*/
if (udev->bus->b_hnp_enable || udev->bus->is_b_host) {
static int __usb_suspend_device(struct usb_device *,
int port1);
err = __usb_suspend_device(udev, udev->bus->otg_port);
if (err < 0)
dev_dbg(&udev->dev, "HNP fail, %d\n", err);
}
err = -ENODEV;
goto fail;
}
#endif
/* put device-specific files into sysfs */
err = device_add (&udev->dev);
if (err) {
dev_err(&udev->dev, "can't device_add, error %d\n", err);
goto fail;
}
usb_create_sysfs_dev_files (udev);
usb_lock_device(udev);
/* choose and set the configuration. that registers the interfaces
* with the driver core, and lets usb device drivers bind to them.
*/
c = choose_configuration(udev);
if (c >= 0) {
err = usb_set_configuration(udev, c);
if (err) {
dev_err(&udev->dev, "can't set config #%d, error %d\n",
c, err);
/* This need not be fatal. The user can try to
* set other configurations. */
}
}
/* USB device state == configured ... usable */
usb_notify_add_device(udev);
usb_unlock_device(udev);
return 0;
fail:
usb_set_device_state(udev, USB_STATE_NOTATTACHED);
return err;
}
static int hub_port_status(struct usb_hub *hub, int port1,
u16 *status, u16 *change)
{
int ret;
ret = get_port_status(hub->hdev, port1, &hub->status->port);
if (ret < 0)
dev_err (hub->intfdev,
"%s failed (err = %d)\n", __FUNCTION__, ret);
else {
*status = le16_to_cpu(hub->status->port.wPortStatus);
*change = le16_to_cpu(hub->status->port.wPortChange);
ret = 0;
}
return ret;
}
#define PORT_RESET_TRIES 5
#define SET_ADDRESS_TRIES 2
#define GET_DESCRIPTOR_TRIES 2
#define SET_CONFIG_TRIES (2 * (use_both_schemes + 1))
#define USE_NEW_SCHEME(i) ((i) / 2 == old_scheme_first)
#define HUB_ROOT_RESET_TIME 50 /* times are in msec */
#define HUB_SHORT_RESET_TIME 10
#define HUB_LONG_RESET_TIME 200
#define HUB_RESET_TIMEOUT 500
static int hub_port_wait_reset(struct usb_hub *hub, int port1,
struct usb_device *udev, unsigned int delay)
{
int delay_time, ret;
u16 portstatus;
u16 portchange;
for (delay_time = 0;
delay_time < HUB_RESET_TIMEOUT;
delay_time += delay) {
/* wait to give the device a chance to reset */
msleep(delay);
/* read and decode port status */
ret = hub_port_status(hub, port1, &portstatus, &portchange);
if (ret < 0)
return ret;
/* Device went away? */
if (!(portstatus & USB_PORT_STAT_CONNECTION))
return -ENOTCONN;
/* bomb out completely if something weird happened */
if ((portchange & USB_PORT_STAT_C_CONNECTION))
return -EINVAL;
/* if we`ve finished resetting, then break out of the loop */
if (!(portstatus & USB_PORT_STAT_RESET) &&
(portstatus & USB_PORT_STAT_ENABLE)) {
if (portstatus & USB_PORT_STAT_HIGH_SPEED)
udev->speed = USB_SPEED_HIGH;
else if (portstatus & USB_PORT_STAT_LOW_SPEED)
udev->speed = USB_SPEED_LOW;
else
udev->speed = USB_SPEED_FULL;
return 0;
}
/* switch to the long delay after two short delay failures */
if (delay_time >= 2 * HUB_SHORT_RESET_TIME)
delay = HUB_LONG_RESET_TIME;
dev_dbg (hub->intfdev,
"port %d not reset yet, waiting %dms\n",
port1, delay);
}
return -EBUSY;
}
static int hub_port_reset(struct usb_hub *hub, int port1,
struct usb_device *udev, unsigned int delay)
{
int i, status;
/* Reset the port */
for (i = 0; i < PORT_RESET_TRIES; i++) {
status = set_port_feature(hub->hdev,
port1, USB_PORT_FEAT_RESET);
if (status)
dev_err(hub->intfdev,
"cannot reset port %d (err = %d)\n",
port1, status);
else {
status = hub_port_wait_reset(hub, port1, udev, delay);
if (status && status != -ENOTCONN)
dev_dbg(hub->intfdev,
"port_wait_reset: err = %d\n",
status);
}
/* return on disconnect or reset */
switch (status) {
case 0:
/* TRSTRCY = 10 ms; plus some extra */
msleep(10 + 40);
/* FALL THROUGH */
case -ENOTCONN:
case -ENODEV:
clear_port_feature(hub->hdev,
port1, USB_PORT_FEAT_C_RESET);
/* FIXME need disconnect() for NOTATTACHED device */
usb_set_device_state(udev, status
? USB_STATE_NOTATTACHED
: USB_STATE_DEFAULT);
return status;
}
dev_dbg (hub->intfdev,
"port %d not enabled, trying reset again...\n",
port1);
delay = HUB_LONG_RESET_TIME;
}
dev_err (hub->intfdev,
"Cannot enable port %i. Maybe the USB cable is bad?\n",
port1);
return status;
}
/*
* Disable a port and mark a logical connnect-change event, so that some
* time later khubd will disconnect() any existing usb_device on the port
* and will re-enumerate if there actually is a device attached.
*/
static void hub_port_logical_disconnect(struct usb_hub *hub, int port1)
{
dev_dbg(hub->intfdev, "logical disconnect on port %d\n", port1);
hub_port_disable(hub, port1, 1);
/* FIXME let caller ask to power down the port:
* - some devices won't enumerate without a VBUS power cycle
* - SRP saves power that way
* - ... new call, TBD ...
* That's easy if this hub can switch power per-port, and
* khubd reactivates the port later (timer, SRP, etc).
* Powerdown must be optional, because of reset/DFU.
*/
set_bit(port1, hub->change_bits);
kick_khubd(hub);
}
#ifdef CONFIG_USB_SUSPEND
/*
* Selective port suspend reduces power; most suspended devices draw
* less than 500 uA. It's also used in OTG, along with remote wakeup.
* All devices below the suspended port are also suspended.
*
* Devices leave suspend state when the host wakes them up. Some devices
* also support "remote wakeup", where the device can activate the USB
* tree above them to deliver data, such as a keypress or packet. In
* some cases, this wakes the USB host.
*/
static int hub_port_suspend(struct usb_hub *hub, int port1,
struct usb_device *udev)
{
int status;
// dev_dbg(hub->intfdev, "suspend port %d\n", port1);
/* enable remote wakeup when appropriate; this lets the device
* wake up the upstream hub (including maybe the root hub).
*
* NOTE: OTG devices may issue remote wakeup (or SRP) even when
* we don't explicitly enable it here.
*/
if (device_may_wakeup(&udev->dev)) {
status = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
USB_REQ_SET_FEATURE, USB_RECIP_DEVICE,
USB_DEVICE_REMOTE_WAKEUP, 0,
NULL, 0,
USB_CTRL_SET_TIMEOUT);
if (status)
dev_dbg(&udev->dev,
"won't remote wakeup, status %d\n",
status);
}
/* see 7.1.7.6 */
status = set_port_feature(hub->hdev, port1, USB_PORT_FEAT_SUSPEND);
if (status) {
dev_dbg(hub->intfdev,
"can't suspend port %d, status %d\n",
port1, status);
/* paranoia: "should not happen" */
(void) usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
USB_REQ_CLEAR_FEATURE, USB_RECIP_DEVICE,
USB_DEVICE_REMOTE_WAKEUP, 0,
NULL, 0,
USB_CTRL_SET_TIMEOUT);
} else {
/* device has up to 10 msec to fully suspend */
dev_dbg(&udev->dev, "usb suspend\n");
usb_set_device_state(udev, USB_STATE_SUSPENDED);
msleep(10);
}
return status;
}
/*
* Devices on USB hub ports have only one "suspend" state, corresponding
* to ACPI D2, "may cause the device to lose some context".
* State transitions include:
*
* - suspend, resume ... when the VBUS power link stays live
* - suspend, disconnect ... VBUS lost
*
* Once VBUS drop breaks the circuit, the port it's using has to go through
* normal re-enumeration procedures, starting with enabling VBUS power.
* Other than re-initializing the hub (plug/unplug, except for root hubs),
* Linux (2.6) currently has NO mechanisms to initiate that: no khubd
* timer, no SRP, no requests through sysfs.
*
* If CONFIG_USB_SUSPEND isn't enabled, devices only really suspend when
* the root hub for their bus goes into global suspend ... so we don't
* (falsely) update the device power state to say it suspended.
*/
static int __usb_suspend_device (struct usb_device *udev, int port1)
{
int status = 0;
/* caller owns the udev device lock */
if (port1 < 0)
return port1;
if (udev->state == USB_STATE_SUSPENDED
|| udev->state == USB_STATE_NOTATTACHED) {
return 0;
}
/* all interfaces must already be suspended */
if (udev->actconfig) {
int i;
for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
struct usb_interface *intf;
intf = udev->actconfig->interface[i];
if (is_active(intf)) {
dev_dbg(&intf->dev, "nyet suspended\n");
return -EBUSY;
}
}
}
/* we only change a device's upstream USB link.
* root hubs have no upstream USB link.
*/
if (udev->parent)
status = hub_port_suspend(hdev_to_hub(udev->parent), port1,
udev);
if (status == 0)
udev->dev.power.power_state = PMSG_SUSPEND;
return status;
}
#endif
/*
* usb_suspend_device - suspend a usb device
* @udev: device that's no longer in active use
* Context: must be able to sleep; device not locked; pm locks held
*
* Suspends a USB device that isn't in active use, conserving power.
* Devices may wake out of a suspend, if anything important happens,
* using the remote wakeup mechanism. They may also be taken out of
* suspend by the host, using usb_resume_device(). It's also routine
* to disconnect devices while they are suspended.
*
* This only affects the USB hardware for a device; its interfaces
* (and, for hubs, child devices) must already have been suspended.
*
* Suspending OTG devices may trigger HNP, if that's been enabled
* between a pair of dual-role devices. That will change roles, such
* as from A-Host to A-Peripheral or from B-Host back to B-Peripheral.
*
* Returns 0 on success, else negative errno.
*/
int usb_suspend_device(struct usb_device *udev)
{
#ifdef CONFIG_USB_SUSPEND
if (udev->state == USB_STATE_NOTATTACHED)
return -ENODEV;
return __usb_suspend_device(udev, udev->portnum);
#else
/* NOTE: udev->state unchanged, it's not lying ... */
udev->dev.power.power_state = PMSG_SUSPEND;
return 0;
#endif
}
/*
* If the USB "suspend" state is in use (rather than "global suspend"),
* many devices will be individually taken out of suspend state using
* special" resume" signaling. These routines kick in shortly after
* hardware resume signaling is finished, either because of selective
* resume (by host) or remote wakeup (by device) ... now see what changed
* in the tree that's rooted at this device.
*/
static int finish_device_resume(struct usb_device *udev)
{
int status;
u16 devstatus;
/* caller owns the udev device lock */
dev_dbg(&udev->dev, "finish resume\n");
/* usb ch9 identifies four variants of SUSPENDED, based on what
* state the device resumes to. Linux currently won't see the
* first two on the host side; they'd be inside hub_port_init()
* during many timeouts, but khubd can't suspend until later.
*/
usb_set_device_state(udev, udev->actconfig
? USB_STATE_CONFIGURED
: USB_STATE_ADDRESS);
udev->dev.power.power_state = PMSG_ON;
/* 10.5.4.5 says be sure devices in the tree are still there.
* For now let's assume the device didn't go crazy on resume,
* and device drivers will know about any resume quirks.
*/
status = usb_get_status(udev, USB_RECIP_DEVICE, 0, &devstatus);
if (status < 2)
dev_dbg(&udev->dev,
"gone after usb resume? status %d\n",
status);
else if (udev->actconfig) {
unsigned i;
int (*resume)(struct device *);
le16_to_cpus(&devstatus);
if ((devstatus & (1 << USB_DEVICE_REMOTE_WAKEUP))
&& udev->parent) {
status = usb_control_msg(udev,
usb_sndctrlpipe(udev, 0),
USB_REQ_CLEAR_FEATURE,
USB_RECIP_DEVICE,
USB_DEVICE_REMOTE_WAKEUP, 0,
NULL, 0,
USB_CTRL_SET_TIMEOUT);
if (status) {
dev_dbg(&udev->dev, "disable remote "
"wakeup, status %d\n", status);
status = 0;
}
}
/* resume interface drivers; if this is a hub, it
* may have a child resume event to deal with soon
*/
resume = udev->dev.bus->resume;
for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
struct device *dev =
&udev->actconfig->interface[i]->dev;
down(&dev->sem);
(void) resume(dev);
up(&dev->sem);
}
status = 0;
} else if (udev->devnum <= 0) {
dev_dbg(&udev->dev, "bogus resume!\n");
status = -EINVAL;
}
return status;
}
#ifdef CONFIG_USB_SUSPEND
static int
hub_port_resume(struct usb_hub *hub, int port1, struct usb_device *udev)
{
int status;
// dev_dbg(hub->intfdev, "resume port %d\n", port1);
/* see 7.1.7.7; affects power usage, but not budgeting */
status = clear_port_feature(hub->hdev,
port1, USB_PORT_FEAT_SUSPEND);
if (status) {
dev_dbg(hub->intfdev,
"can't resume port %d, status %d\n",
port1, status);
} else {
u16 devstatus;
u16 portchange;
/* drive resume for at least 20 msec */
if (udev)
dev_dbg(&udev->dev, "RESUME\n");
msleep(25);
#define LIVE_FLAGS ( USB_PORT_STAT_POWER \
| USB_PORT_STAT_ENABLE \
| USB_PORT_STAT_CONNECTION)
/* Virtual root hubs can trigger on GET_PORT_STATUS to
* stop resume signaling. Then finish the resume
* sequence.
*/
devstatus = portchange = 0;
status = hub_port_status(hub, port1,
&devstatus, &portchange);
if (status < 0
|| (devstatus & LIVE_FLAGS) != LIVE_FLAGS
|| (devstatus & USB_PORT_STAT_SUSPEND) != 0
) {
dev_dbg(hub->intfdev,
"port %d status %04x.%04x after resume, %d\n",
port1, portchange, devstatus, status);
} else {
/* TRSMRCY = 10 msec */
msleep(10);
if (udev)
status = finish_device_resume(udev);
}
}
if (status < 0)
hub_port_logical_disconnect(hub, port1);
return status;
}
#endif
/*
* usb_resume_device - re-activate a suspended usb device
* @udev: device to re-activate
* Context: must be able to sleep; device not locked; pm locks held
*
* This will re-activate the suspended device, increasing power usage
* while letting drivers communicate again with its endpoints.
* USB resume explicitly guarantees that the power session between
* the host and the device is the same as it was when the device
* suspended.
*
* Returns 0 on success, else negative errno.
*/
int usb_resume_device(struct usb_device *udev)
{
int status;
if (udev->state == USB_STATE_NOTATTACHED)
return -ENODEV;
#ifdef CONFIG_USB_SUSPEND
/* selective resume of one downstream hub-to-device port */
if (udev->parent) {
if (udev->state == USB_STATE_SUSPENDED) {
// NOTE swsusp may bork us, device state being wrong...
// NOTE this fails if parent is also suspended...
status = hub_port_resume(hdev_to_hub(udev->parent),
udev->portnum, udev);
} else
status = 0;
} else
#endif
status = finish_device_resume(udev);
if (status < 0)
dev_dbg(&udev->dev, "can't resume, status %d\n",
status);
/* rebind drivers that had no suspend() */
if (status == 0) {
usb_unlock_device(udev);
bus_rescan_devices(&usb_bus_type);
usb_lock_device(udev);
}
return status;
}
static int remote_wakeup(struct usb_device *udev)
{
int status = 0;
#ifdef CONFIG_USB_SUSPEND
/* don't repeat RESUME sequence if this device
* was already woken up by some other task
*/
usb_lock_device(udev);
if (udev->state == USB_STATE_SUSPENDED) {
dev_dbg(&udev->dev, "RESUME (wakeup)\n");
/* TRSMRCY = 10 msec */
msleep(10);
status = finish_device_resume(udev);
}
usb_unlock_device(udev);
#endif
return status;
}
static int hub_suspend(struct usb_interface *intf, pm_message_t msg)
{
struct usb_hub *hub = usb_get_intfdata (intf);
struct usb_device *hdev = hub->hdev;
unsigned port1;
/* fail if children aren't already suspended */
for (port1 = 1; port1 <= hdev->maxchild; port1++) {
struct usb_device *udev;
udev = hdev->children [port1-1];
if (udev && (udev->dev.power.power_state.event
== PM_EVENT_ON
#ifdef CONFIG_USB_SUSPEND
|| udev->state != USB_STATE_SUSPENDED
#endif
)) {
dev_dbg(&intf->dev, "port %d nyet suspended\n", port1);
return -EBUSY;
}
}
/* "global suspend" of the downstream HC-to-USB interface */
if (!hdev->parent) {
struct usb_bus *bus = hdev->bus;
if (bus) {
int status = hcd_bus_suspend (bus);
if (status != 0) {
dev_dbg(&hdev->dev, "'global' suspend %d\n",
status);
return status;
}
} else
return -EOPNOTSUPP;
}
/* stop khubd and related activity */
hub_quiesce(hub);
return 0;
}
static int hub_resume(struct usb_interface *intf)
{
struct usb_device *hdev = interface_to_usbdev(intf);
struct usb_hub *hub = usb_get_intfdata (intf);
int status;
/* "global resume" of the downstream HC-to-USB interface */
if (!hdev->parent) {
struct usb_bus *bus = hdev->bus;
if (bus) {
status = hcd_bus_resume (bus);
if (status) {
dev_dbg(&intf->dev, "'global' resume %d\n",
status);
return status;
}
} else
return -EOPNOTSUPP;
if (status == 0) {
/* TRSMRCY = 10 msec */
msleep(10);
}
}
hub_activate(hub);
/* REVISIT: this recursion probably shouldn't exist. Remove
* this code sometime, after retesting with different root and
* external hubs.
*/
#ifdef CONFIG_USB_SUSPEND
{
unsigned port1;
for (port1 = 1; port1 <= hdev->maxchild; port1++) {
struct usb_device *udev;
u16 portstat, portchange;
udev = hdev->children [port1-1];
status = hub_port_status(hub, port1, &portstat, &portchange);
if (status == 0) {
if (portchange & USB_PORT_STAT_C_SUSPEND) {
clear_port_feature(hdev, port1,
USB_PORT_FEAT_C_SUSPEND);
portchange &= ~USB_PORT_STAT_C_SUSPEND;
}
/* let khubd handle disconnects etc */
if (portchange)
continue;
}
if (!udev || status < 0)
continue;
usb_lock_device(udev);
if (portstat & USB_PORT_STAT_SUSPEND)
status = hub_port_resume(hub, port1, udev);
else {
status = finish_device_resume(udev);
if (status < 0) {
dev_dbg(&intf->dev, "resume port %d --> %d\n",
port1, status);
hub_port_logical_disconnect(hub, port1);
}
}
usb_unlock_device(udev);
}
}
#endif
return 0;
}
void usb_suspend_root_hub(struct usb_device *hdev)
{
struct usb_hub *hub = hdev_to_hub(hdev);
/* This also makes any led blinker stop retriggering. We're called
* from irq, so the blinker might still be scheduled. Caller promises
* that the root hub status URB will be canceled.
*/
__hub_quiesce(hub);
mark_quiesced(to_usb_interface(hub->intfdev));
}
void usb_resume_root_hub(struct usb_device *hdev)
{
struct usb_hub *hub = hdev_to_hub(hdev);
hub->resume_root_hub = 1;
kick_khubd(hub);
}
/* USB 2.0 spec, 7.1.7.3 / fig 7-29:
*
* Between connect detection and reset signaling there must be a delay
* of 100ms at least for debounce and power-settling. The corresponding
* timer shall restart whenever the downstream port detects a disconnect.
*
* Apparently there are some bluetooth and irda-dongles and a number of
* low-speed devices for which this debounce period may last over a second.
* Not covered by the spec - but easy to deal with.
*
* This implementation uses a 1500ms total debounce timeout; if the
* connection isn't stable by then it returns -ETIMEDOUT. It checks
* every 25ms for transient disconnects. When the port status has been
* unchanged for 100ms it returns the port status.
*/
#define HUB_DEBOUNCE_TIMEOUT 1500
#define HUB_DEBOUNCE_STEP 25
#define HUB_DEBOUNCE_STABLE 100
static int hub_port_debounce(struct usb_hub *hub, int port1)
{
int ret;
int total_time, stable_time = 0;
u16 portchange, portstatus;
unsigned connection = 0xffff;
for (total_time = 0; ; total_time += HUB_DEBOUNCE_STEP) {
ret = hub_port_status(hub, port1, &portstatus, &portchange);
if (ret < 0)
return ret;
if (!(portchange & USB_PORT_STAT_C_CONNECTION) &&
(portstatus & USB_PORT_STAT_CONNECTION) == connection) {
stable_time += HUB_DEBOUNCE_STEP;
if (stable_time >= HUB_DEBOUNCE_STABLE)
break;
} else {
stable_time = 0;
connection = portstatus & USB_PORT_STAT_CONNECTION;
}
if (portchange & USB_PORT_STAT_C_CONNECTION) {
clear_port_feature(hub->hdev, port1,
USB_PORT_FEAT_C_CONNECTION);
}
if (total_time >= HUB_DEBOUNCE_TIMEOUT)
break;
msleep(HUB_DEBOUNCE_STEP);
}
dev_dbg (hub->intfdev,
"debounce: port %d: total %dms stable %dms status 0x%x\n",
port1, total_time, stable_time, portstatus);
if (stable_time < HUB_DEBOUNCE_STABLE)
return -ETIMEDOUT;
return portstatus;
}
static void ep0_reinit(struct usb_device *udev)
{
usb_disable_endpoint(udev, 0 + USB_DIR_IN);
usb_disable_endpoint(udev, 0 + USB_DIR_OUT);
udev->ep_in[0] = udev->ep_out[0] = &udev->ep0;
}
#define usb_sndaddr0pipe() (PIPE_CONTROL << 30)
#define usb_rcvaddr0pipe() ((PIPE_CONTROL << 30) | USB_DIR_IN)
static int hub_set_address(struct usb_device *udev)
{
int retval;
if (udev->devnum == 0)
return -EINVAL;
if (udev->state == USB_STATE_ADDRESS)
return 0;
if (udev->state != USB_STATE_DEFAULT)
return -EINVAL;
retval = usb_control_msg(udev, usb_sndaddr0pipe(),
USB_REQ_SET_ADDRESS, 0, udev->devnum, 0,
NULL, 0, USB_CTRL_SET_TIMEOUT);
if (retval == 0) {
usb_set_device_state(udev, USB_STATE_ADDRESS);
ep0_reinit(udev);
}
return retval;
}
/* Reset device, (re)assign address, get device descriptor.
* Device connection must be stable, no more debouncing needed.
* Returns device in USB_STATE_ADDRESS, except on error.
*
* If this is called for an already-existing device (as part of
* usb_reset_device), the caller must own the device lock. For a
* newly detected device that is not accessible through any global
* pointers, it's not necessary to lock the device.
*/
static int
hub_port_init (struct usb_hub *hub, struct usb_device *udev, int port1,
int retry_counter)
{
static DECLARE_MUTEX(usb_address0_sem);
struct usb_device *hdev = hub->hdev;
int i, j, retval;
unsigned delay = HUB_SHORT_RESET_TIME;
enum usb_device_speed oldspeed = udev->speed;
/* root hub ports have a slightly longer reset period
* (from USB 2.0 spec, section 7.1.7.5)
*/
if (!hdev->parent) {
delay = HUB_ROOT_RESET_TIME;
if (port1 == hdev->bus->otg_port)
hdev->bus->b_hnp_enable = 0;
}
/* Some low speed devices have problems with the quick delay, so */
/* be a bit pessimistic with those devices. RHbug #23670 */
if (oldspeed == USB_SPEED_LOW)
delay = HUB_LONG_RESET_TIME;
down(&usb_address0_sem);
/* Reset the device; full speed may morph to high speed */
retval = hub_port_reset(hub, port1, udev, delay);
if (retval < 0) /* error or disconnect */
goto fail;
/* success, speed is known */
retval = -ENODEV;
if (oldspeed != USB_SPEED_UNKNOWN && oldspeed != udev->speed) {
dev_dbg(&udev->dev, "device reset changed speed!\n");
goto fail;
}
oldspeed = udev->speed;
/* USB 2.0 section 5.5.3 talks about ep0 maxpacket ...
* it's fixed size except for full speed devices.
*/
switch (udev->speed) {
case USB_SPEED_HIGH: /* fixed at 64 */
udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(64);
break;
case USB_SPEED_FULL: /* 8, 16, 32, or 64 */
/* to determine the ep0 maxpacket size, try to read
* the device descriptor to get bMaxPacketSize0 and
* then correct our initial guess.
*/
udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(64);
break;
case USB_SPEED_LOW: /* fixed at 8 */
udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(8);
break;
default:
goto fail;
}
dev_info (&udev->dev,
"%s %s speed USB device using %s and address %d\n",
(udev->config) ? "reset" : "new",
({ char *speed; switch (udev->speed) {
case USB_SPEED_LOW: speed = "low"; break;
case USB_SPEED_FULL: speed = "full"; break;
case USB_SPEED_HIGH: speed = "high"; break;
default: speed = "?"; break;
}; speed;}),
udev->bus->controller->driver->name,
udev->devnum);
/* Set up TT records, if needed */
if (hdev->tt) {
udev->tt = hdev->tt;
udev->ttport = hdev->ttport;
} else if (udev->speed != USB_SPEED_HIGH
&& hdev->speed == USB_SPEED_HIGH) {
udev->tt = &hub->tt;
udev->ttport = port1;
}
/* Why interleave GET_DESCRIPTOR and SET_ADDRESS this way?
* Because device hardware and firmware is sometimes buggy in
* this area, and this is how Linux has done it for ages.
* Change it cautiously.
*
* NOTE: If USE_NEW_SCHEME() is true we will start by issuing
* a 64-byte GET_DESCRIPTOR request. This is what Windows does,
* so it may help with some non-standards-compliant devices.
* Otherwise we start with SET_ADDRESS and then try to read the
* first 8 bytes of the device descriptor to get the ep0 maxpacket
* value.
*/
for (i = 0; i < GET_DESCRIPTOR_TRIES; (++i, msleep(100))) {
if (USE_NEW_SCHEME(retry_counter)) {
struct usb_device_descriptor *buf;
int r = 0;
#define GET_DESCRIPTOR_BUFSIZE 64
buf = kmalloc(GET_DESCRIPTOR_BUFSIZE, GFP_NOIO);
if (!buf) {
retval = -ENOMEM;
continue;
}
/* Use a short timeout the first time through,
* so that recalcitrant full-speed devices with
* 8- or 16-byte ep0-maxpackets won't slow things
* down tremendously by NAKing the unexpectedly
* early status stage. Also, retry on all errors;
* some devices are flakey.
*/
for (j = 0; j < 3; ++j) {
buf->bMaxPacketSize0 = 0;
r = usb_control_msg(udev, usb_rcvaddr0pipe(),
USB_REQ_GET_DESCRIPTOR, USB_DIR_IN,
USB_DT_DEVICE << 8, 0,
buf, GET_DESCRIPTOR_BUFSIZE,
(i ? USB_CTRL_GET_TIMEOUT : 1000));
switch (buf->bMaxPacketSize0) {
case 8: case 16: case 32: case 64:
if (buf->bDescriptorType ==
USB_DT_DEVICE) {
r = 0;
break;
}
/* FALL THROUGH */
default:
if (r == 0)
r = -EPROTO;
break;
}
if (r == 0)
break;
}
udev->descriptor.bMaxPacketSize0 =
buf->bMaxPacketSize0;
kfree(buf);
retval = hub_port_reset(hub, port1, udev, delay);
if (retval < 0) /* error or disconnect */
goto fail;
if (oldspeed != udev->speed) {
dev_dbg(&udev->dev,
"device reset changed speed!\n");
retval = -ENODEV;
goto fail;
}
if (r) {
dev_err(&udev->dev, "device descriptor "
"read/%s, error %d\n",
"64", r);
retval = -EMSGSIZE;
continue;
}
#undef GET_DESCRIPTOR_BUFSIZE
}
for (j = 0; j < SET_ADDRESS_TRIES; ++j) {
retval = hub_set_address(udev);
if (retval >= 0)
break;
msleep(200);
}
if (retval < 0) {
dev_err(&udev->dev,
"device not accepting address %d, error %d\n",
udev->devnum, retval);
goto fail;
}
/* cope with hardware quirkiness:
* - let SET_ADDRESS settle, some device hardware wants it
* - read ep0 maxpacket even for high and low speed,
*/
msleep(10);
if (USE_NEW_SCHEME(retry_counter))
break;
retval = usb_get_device_descriptor(udev, 8);
if (retval < 8) {
dev_err(&udev->dev, "device descriptor "
"read/%s, error %d\n",
"8", retval);
if (retval >= 0)
retval = -EMSGSIZE;
} else {
retval = 0;
break;
}
}
if (retval)
goto fail;
i = udev->descriptor.bMaxPacketSize0;
if (le16_to_cpu(udev->ep0.desc.wMaxPacketSize) != i) {
if (udev->speed != USB_SPEED_FULL ||
!(i == 8 || i == 16 || i == 32 || i == 64)) {
dev_err(&udev->dev, "ep0 maxpacket = %d\n", i);
retval = -EMSGSIZE;
goto fail;
}
dev_dbg(&udev->dev, "ep0 maxpacket = %d\n", i);
udev->ep0.desc.wMaxPacketSize = cpu_to_le16(i);
ep0_reinit(udev);
}
retval = usb_get_device_descriptor(udev, USB_DT_DEVICE_SIZE);
if (retval < (signed)sizeof(udev->descriptor)) {
dev_err(&udev->dev, "device descriptor read/%s, error %d\n",
"all", retval);
if (retval >= 0)
retval = -ENOMSG;
goto fail;
}
retval = 0;
fail:
if (retval)
hub_port_disable(hub, port1, 0);
up(&usb_address0_sem);
return retval;
}
static void
check_highspeed (struct usb_hub *hub, struct usb_device *udev, int port1)
{
struct usb_qualifier_descriptor *qual;
int status;
qual = kmalloc (sizeof *qual, SLAB_KERNEL);
if (qual == NULL)
return;
status = usb_get_descriptor (udev, USB_DT_DEVICE_QUALIFIER, 0,
qual, sizeof *qual);
if (status == sizeof *qual) {
dev_info(&udev->dev, "not running at top speed; "
"connect to a high speed hub\n");
/* hub LEDs are probably harder to miss than syslog */
if (hub->has_indicators) {
hub->indicator[port1-1] = INDICATOR_GREEN_BLINK;
schedule_work (&hub->leds);
}
}
kfree(qual);
}
static unsigned
hub_power_remaining (struct usb_hub *hub)
{
struct usb_device *hdev = hub->hdev;
int remaining;
int port1;
if (!hub->limited_power)
return 0;
remaining = hdev->bus_mA - hub->descriptor->bHubContrCurrent;
for (port1 = 1; port1 <= hdev->maxchild; ++port1) {
struct usb_device *udev = hdev->children[port1 - 1];
int delta;
if (!udev)
continue;
/* Unconfigured devices may not use more than 100mA,
* or 8mA for OTG ports */
if (udev->actconfig)
delta = udev->actconfig->desc.bMaxPower * 2;
else if (port1 != udev->bus->otg_port || hdev->parent)
delta = 100;
else
delta = 8;
if (delta > hub->mA_per_port)
dev_warn(&udev->dev, "%dmA is over %umA budget "
"for port %d!\n",
delta, hub->mA_per_port, port1);
remaining -= delta;
}
if (remaining < 0) {
dev_warn(hub->intfdev, "%dmA over power budget!\n",
- remaining);
remaining = 0;
}
return remaining;
}
/* Handle physical or logical connection change events.
* This routine is called when:
* a port connection-change occurs;
* a port enable-change occurs (often caused by EMI);
* usb_reset_device() encounters changed descriptors (as from
* a firmware download)
* caller already locked the hub
*/
static void hub_port_connect_change(struct usb_hub *hub, int port1,
u16 portstatus, u16 portchange)
{
struct usb_device *hdev = hub->hdev;
struct device *hub_dev = hub->intfdev;
u16 wHubCharacteristics = le16_to_cpu(hub->descriptor->wHubCharacteristics);
int status, i;
dev_dbg (hub_dev,
"port %d, status %04x, change %04x, %s\n",
port1, portstatus, portchange, portspeed (portstatus));
if (hub->has_indicators) {
set_port_led(hub, port1, HUB_LED_AUTO);
hub->indicator[port1-1] = INDICATOR_AUTO;
}
/* Disconnect any existing devices under this port */
if (hdev->children[port1-1])
usb_disconnect(&hdev->children[port1-1]);
clear_bit(port1, hub->change_bits);
#ifdef CONFIG_USB_OTG
/* during HNP, don't repeat the debounce */
if (hdev->bus->is_b_host)
portchange &= ~USB_PORT_STAT_C_CONNECTION;
#endif
if (portchange & USB_PORT_STAT_C_CONNECTION) {
status = hub_port_debounce(hub, port1);
if (status < 0) {
dev_err (hub_dev,
"connect-debounce failed, port %d disabled\n",
port1);
goto done;
}
portstatus = status;
}
/* Return now if nothing is connected */
if (!(portstatus & USB_PORT_STAT_CONNECTION)) {
/* maybe switch power back on (e.g. root hub was reset) */
if ((wHubCharacteristics & HUB_CHAR_LPSM) < 2
&& !(portstatus & (1 << USB_PORT_FEAT_POWER)))
set_port_feature(hdev, port1, USB_PORT_FEAT_POWER);
if (portstatus & USB_PORT_STAT_ENABLE)
goto done;
return;
}
#ifdef CONFIG_USB_SUSPEND
/* If something is connected, but the port is suspended, wake it up. */
if (portstatus & USB_PORT_STAT_SUSPEND) {
status = hub_port_resume(hub, port1, NULL);
if (status < 0) {
dev_dbg(hub_dev,
"can't clear suspend on port %d; %d\n",
port1, status);
goto done;
}
}
#endif
for (i = 0; i < SET_CONFIG_TRIES; i++) {
struct usb_device *udev;
/* reallocate for each attempt, since references
* to the previous one can escape in various ways
*/
udev = usb_alloc_dev(hdev, hdev->bus, port1);
if (!udev) {
dev_err (hub_dev,
"couldn't allocate port %d usb_device\n",
port1);
goto done;
}
usb_set_device_state(udev, USB_STATE_POWERED);
udev->speed = USB_SPEED_UNKNOWN;
udev->bus_mA = hub->mA_per_port;
/* set the address */
choose_address(udev);
if (udev->devnum <= 0) {
status = -ENOTCONN; /* Don't retry */
goto loop;
}
/* reset and get descriptor */
status = hub_port_init(hub, udev, port1, i);
if (status < 0)
goto loop;
/* consecutive bus-powered hubs aren't reliable; they can
* violate the voltage drop budget. if the new child has
* a "powered" LED, users should notice we didn't enable it
* (without reading syslog), even without per-port LEDs
* on the parent.
*/
if (udev->descriptor.bDeviceClass == USB_CLASS_HUB
&& udev->bus_mA <= 100) {
u16 devstat;
status = usb_get_status(udev, USB_RECIP_DEVICE, 0,
&devstat);
if (status < 2) {
dev_dbg(&udev->dev, "get status %d ?\n", status);
goto loop_disable;
}
le16_to_cpus(&devstat);
if ((devstat & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
dev_err(&udev->dev,
"can't connect bus-powered hub "
"to this port\n");
if (hub->has_indicators) {
hub->indicator[port1-1] =
INDICATOR_AMBER_BLINK;
schedule_work (&hub->leds);
}
status = -ENOTCONN; /* Don't retry */
goto loop_disable;
}
}
/* check for devices running slower than they could */
if (le16_to_cpu(udev->descriptor.bcdUSB) >= 0x0200
&& udev->speed == USB_SPEED_FULL
&& highspeed_hubs != 0)
check_highspeed (hub, udev, port1);
/* Store the parent's children[] pointer. At this point
* udev becomes globally accessible, although presumably
* no one will look at it until hdev is unlocked.
*/
status = 0;
/* We mustn't add new devices if the parent hub has
* been disconnected; we would race with the
* recursively_mark_NOTATTACHED() routine.
*/
spin_lock_irq(&device_state_lock);
if (hdev->state == USB_STATE_NOTATTACHED)
status = -ENOTCONN;
else
hdev->children[port1-1] = udev;
spin_unlock_irq(&device_state_lock);
/* Run it through the hoops (find a driver, etc) */
if (!status) {
status = usb_new_device(udev);
if (status) {
spin_lock_irq(&device_state_lock);
hdev->children[port1-1] = NULL;
spin_unlock_irq(&device_state_lock);
}
}
if (status)
goto loop_disable;
status = hub_power_remaining(hub);
if (status)
dev_dbg(hub_dev, "%dmA power budget left\n", status);
return;
loop_disable:
hub_port_disable(hub, port1, 1);
loop:
ep0_reinit(udev);
release_address(udev);
usb_put_dev(udev);
if (status == -ENOTCONN)
break;
}
done:
hub_port_disable(hub, port1, 1);
}
static void hub_events(void)
{
struct list_head *tmp;
struct usb_device *hdev;
struct usb_interface *intf;
struct usb_hub *hub;
struct device *hub_dev;
u16 hubstatus;
u16 hubchange;
u16 portstatus;
u16 portchange;
int i, ret;
int connect_change;
/*
* We restart the list every time to avoid a deadlock with
* deleting hubs downstream from this one. This should be
* safe since we delete the hub from the event list.
* Not the most efficient, but avoids deadlocks.
*/
while (1) {
/* Grab the first entry at the beginning of the list */
spin_lock_irq(&hub_event_lock);
if (list_empty(&hub_event_list)) {
spin_unlock_irq(&hub_event_lock);
break;
}
tmp = hub_event_list.next;
list_del_init(tmp);
hub = list_entry(tmp, struct usb_hub, event_list);
hdev = hub->hdev;
intf = to_usb_interface(hub->intfdev);
hub_dev = &intf->dev;
i = hub->resume_root_hub;
dev_dbg(hub_dev, "state %d ports %d chg %04x evt %04x%s\n",
hdev->state, hub->descriptor
? hub->descriptor->bNbrPorts
: 0,
/* NOTE: expects max 15 ports... */
(u16) hub->change_bits[0],
(u16) hub->event_bits[0],
i ? ", resume root" : "");
usb_get_intf(intf);
spin_unlock_irq(&hub_event_lock);
/* Is this is a root hub wanting to reactivate the downstream
* ports? If so, be sure the interface resumes even if its
* stub "device" node was never suspended.
*/
if (i) {
dpm_runtime_resume(&hdev->dev);
dpm_runtime_resume(&intf->dev);
usb_put_intf(intf);
continue;
}
/* Lock the device, then check to see if we were
* disconnected while waiting for the lock to succeed. */
if (locktree(hdev) < 0) {
usb_put_intf(intf);
continue;
}
if (hub != usb_get_intfdata(intf))
goto loop;
/* If the hub has died, clean up after it */
if (hdev->state == USB_STATE_NOTATTACHED) {
hub_pre_reset(hub, 0);
goto loop;
}
/* If this is an inactive or suspended hub, do nothing */
if (hub->quiescing)
goto loop;
if (hub->error) {
dev_dbg (hub_dev, "resetting for error %d\n",
hub->error);
ret = usb_reset_device(hdev);
if (ret) {
dev_dbg (hub_dev,
"error resetting hub: %d\n", ret);
goto loop;
}
hub->nerrors = 0;
hub->error = 0;
}
/* deal with port status changes */
for (i = 1; i <= hub->descriptor->bNbrPorts; i++) {
if (test_bit(i, hub->busy_bits))
continue;
connect_change = test_bit(i, hub->change_bits);
if (!test_and_clear_bit(i, hub->event_bits) &&
!connect_change && !hub->activating)
continue;
ret = hub_port_status(hub, i,
&portstatus, &portchange);
if (ret < 0)
continue;
if (hub->activating && !hdev->children[i-1] &&
(portstatus &
USB_PORT_STAT_CONNECTION))
connect_change = 1;
if (portchange & USB_PORT_STAT_C_CONNECTION) {
clear_port_feature(hdev, i,
USB_PORT_FEAT_C_CONNECTION);
connect_change = 1;
}
if (portchange & USB_PORT_STAT_C_ENABLE) {
if (!connect_change)
dev_dbg (hub_dev,
"port %d enable change, "
"status %08x\n",
i, portstatus);
clear_port_feature(hdev, i,
USB_PORT_FEAT_C_ENABLE);
/*
* EM interference sometimes causes badly
* shielded USB devices to be shutdown by
* the hub, this hack enables them again.
* Works at least with mouse driver.
*/
if (!(portstatus & USB_PORT_STAT_ENABLE)
&& !connect_change
&& hdev->children[i-1]) {
dev_err (hub_dev,
"port %i "
"disabled by hub (EMI?), "
"re-enabling...\n",
i);
connect_change = 1;
}
}
if (portchange & USB_PORT_STAT_C_SUSPEND) {
clear_port_feature(hdev, i,
USB_PORT_FEAT_C_SUSPEND);
if (hdev->children[i-1]) {
ret = remote_wakeup(hdev->
children[i-1]);
if (ret < 0)
connect_change = 1;
} else {
ret = -ENODEV;
hub_port_disable(hub, i, 1);
}
dev_dbg (hub_dev,
"resume on port %d, status %d\n",
i, ret);
}
if (portchange & USB_PORT_STAT_C_OVERCURRENT) {
dev_err (hub_dev,
"over-current change on port %d\n",
i);
clear_port_feature(hdev, i,
USB_PORT_FEAT_C_OVER_CURRENT);
hub_power_on(hub);
}
if (portchange & USB_PORT_STAT_C_RESET) {
dev_dbg (hub_dev,
"reset change on port %d\n",
i);
clear_port_feature(hdev, i,
USB_PORT_FEAT_C_RESET);
}
if (connect_change)
hub_port_connect_change(hub, i,
portstatus, portchange);
} /* end for i */
/* deal with hub status changes */
if (test_and_clear_bit(0, hub->event_bits) == 0)
; /* do nothing */
else if (hub_hub_status(hub, &hubstatus, &hubchange) < 0)
dev_err (hub_dev, "get_hub_status failed\n");
else {
if (hubchange & HUB_CHANGE_LOCAL_POWER) {
dev_dbg (hub_dev, "power change\n");
clear_hub_feature(hdev, C_HUB_LOCAL_POWER);
if (hubstatus & HUB_STATUS_LOCAL_POWER)
/* FIXME: Is this always true? */
hub->limited_power = 0;
else
hub->limited_power = 1;
}
if (hubchange & HUB_CHANGE_OVERCURRENT) {
dev_dbg (hub_dev, "overcurrent change\n");
msleep(500); /* Cool down */
clear_hub_feature(hdev, C_HUB_OVER_CURRENT);
hub_power_on(hub);
}
}
hub->activating = 0;
/* If this is a root hub, tell the HCD it's okay to
* re-enable port-change interrupts now. */
if (!hdev->parent)
usb_enable_root_hub_irq(hdev->bus);
loop:
usb_unlock_device(hdev);
usb_put_intf(intf);
} /* end while (1) */
}
static int hub_thread(void *__unused)
{
do {
hub_events();
wait_event_interruptible(khubd_wait,
!list_empty(&hub_event_list) ||
kthread_should_stop());
try_to_freeze();
} while (!kthread_should_stop() || !list_empty(&hub_event_list));
pr_debug("%s: khubd exiting\n", usbcore_name);
return 0;
}
static struct usb_device_id hub_id_table [] = {
{ .match_flags = USB_DEVICE_ID_MATCH_DEV_CLASS,
.bDeviceClass = USB_CLASS_HUB},
{ .match_flags = USB_DEVICE_ID_MATCH_INT_CLASS,
.bInterfaceClass = USB_CLASS_HUB},
{ } /* Terminating entry */
};
MODULE_DEVICE_TABLE (usb, hub_id_table);
static struct usb_driver hub_driver = {
.name = "hub",
.probe = hub_probe,
.disconnect = hub_disconnect,
.suspend = hub_suspend,
.resume = hub_resume,
.ioctl = hub_ioctl,
.id_table = hub_id_table,
};
int usb_hub_init(void)
{
if (usb_register(&hub_driver) < 0) {
printk(KERN_ERR "%s: can't register hub driver\n",
usbcore_name);
return -1;
}
khubd_task = kthread_run(hub_thread, NULL, "khubd");
if (!IS_ERR(khubd_task))
return 0;
/* Fall through if kernel_thread failed */
usb_deregister(&hub_driver);
printk(KERN_ERR "%s: can't start khubd\n", usbcore_name);
return -1;
}
void usb_hub_cleanup(void)
{
kthread_stop(khubd_task);
/*
* Hub resources are freed for us by usb_deregister. It calls
* usb_driver_purge on every device which in turn calls that
* devices disconnect function if it is using this driver.
* The hub_disconnect function takes care of releasing the
* individual hub resources. -greg
*/
usb_deregister(&hub_driver);
} /* usb_hub_cleanup() */
static int config_descriptors_changed(struct usb_device *udev)
{
unsigned index;
unsigned len = 0;
struct usb_config_descriptor *buf;
for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
if (len < le16_to_cpu(udev->config[index].desc.wTotalLength))
len = le16_to_cpu(udev->config[index].desc.wTotalLength);
}
buf = kmalloc (len, SLAB_KERNEL);
if (buf == NULL) {
dev_err(&udev->dev, "no mem to re-read configs after reset\n");
/* assume the worst */
return 1;
}
for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
int length;
int old_length = le16_to_cpu(udev->config[index].desc.wTotalLength);
length = usb_get_descriptor(udev, USB_DT_CONFIG, index, buf,
old_length);
if (length < old_length) {
dev_dbg(&udev->dev, "config index %d, error %d\n",
index, length);
break;
}
if (memcmp (buf, udev->rawdescriptors[index], old_length)
!= 0) {
dev_dbg(&udev->dev, "config index %d changed (#%d)\n",
index, buf->bConfigurationValue);
break;
}
}
kfree(buf);
return index != udev->descriptor.bNumConfigurations;
}
/**
* usb_reset_device - perform a USB port reset to reinitialize a device
* @udev: device to reset (not in SUSPENDED or NOTATTACHED state)
*
* WARNING - don't reset any device unless drivers for all of its
* interfaces are expecting that reset! Maybe some driver->reset()
* method should eventually help ensure sufficient cooperation.
*
* Do a port reset, reassign the device's address, and establish its
* former operating configuration. If the reset fails, or the device's
* descriptors change from their values before the reset, or the original
* configuration and altsettings cannot be restored, a flag will be set
* telling khubd to pretend the device has been disconnected and then
* re-connected. All drivers will be unbound, and the device will be
* re-enumerated and probed all over again.
*
* Returns 0 if the reset succeeded, -ENODEV if the device has been
* flagged for logical disconnection, or some other negative error code
* if the reset wasn't even attempted.
*
* The caller must own the device lock. For example, it's safe to use
* this from a driver probe() routine after downloading new firmware.
* For calls that might not occur during probe(), drivers should lock
* the device using usb_lock_device_for_reset().
*/
int usb_reset_device(struct usb_device *udev)
{
struct usb_device *parent_hdev = udev->parent;
struct usb_hub *parent_hub;
struct usb_device_descriptor descriptor = udev->descriptor;
struct usb_hub *hub = NULL;
int i, ret = 0;
int port1 = udev->portnum;
if (udev->state == USB_STATE_NOTATTACHED ||
udev->state == USB_STATE_SUSPENDED) {
dev_dbg(&udev->dev, "device reset not allowed in state %d\n",
udev->state);
return -EINVAL;
}
if (!parent_hdev) {
/* this requires hcd-specific logic; see OHCI hc_restart() */
dev_dbg(&udev->dev, "%s for root hub!\n", __FUNCTION__);
return -EISDIR;
}
parent_hub = hdev_to_hub(parent_hdev);
/* If we're resetting an active hub, take some special actions */
if (udev->actconfig &&
udev->actconfig->interface[0]->dev.driver ==
&hub_driver.driver &&
(hub = hdev_to_hub(udev)) != NULL) {
hub_pre_reset(hub, 0);
}
set_bit(port1, parent_hub->busy_bits);
for (i = 0; i < SET_CONFIG_TRIES; ++i) {
/* ep0 maxpacket size may change; let the HCD know about it.
* Other endpoints will be handled by re-enumeration. */
ep0_reinit(udev);
ret = hub_port_init(parent_hub, udev, port1, i);
if (ret >= 0)
break;
}
clear_bit(port1, parent_hub->busy_bits);
if (ret < 0)
goto re_enumerate;
/* Device might have changed firmware (DFU or similar) */
if (memcmp(&udev->descriptor, &descriptor, sizeof descriptor)
|| config_descriptors_changed (udev)) {
dev_info(&udev->dev, "device firmware changed\n");
udev->descriptor = descriptor; /* for disconnect() calls */
goto re_enumerate;
}
if (!udev->actconfig)
goto done;
ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
USB_REQ_SET_CONFIGURATION, 0,
udev->actconfig->desc.bConfigurationValue, 0,
NULL, 0, USB_CTRL_SET_TIMEOUT);
if (ret < 0) {
dev_err(&udev->dev,
"can't restore configuration #%d (error=%d)\n",
udev->actconfig->desc.bConfigurationValue, ret);
goto re_enumerate;
}
usb_set_device_state(udev, USB_STATE_CONFIGURED);
for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
struct usb_interface *intf = udev->actconfig->interface[i];
struct usb_interface_descriptor *desc;
/* set_interface resets host side toggle even
* for altsetting zero. the interface may have no driver.
*/
desc = &intf->cur_altsetting->desc;
ret = usb_set_interface(udev, desc->bInterfaceNumber,
desc->bAlternateSetting);
if (ret < 0) {
dev_err(&udev->dev, "failed to restore interface %d "
"altsetting %d (error=%d)\n",
desc->bInterfaceNumber,
desc->bAlternateSetting,
ret);
goto re_enumerate;
}
}
done:
if (hub)
hub_post_reset(hub);
return 0;
re_enumerate:
hub_port_logical_disconnect(parent_hub, port1);
return -ENODEV;
}
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