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gerrit-public.fairphone.software / kernel / msm-4.9 / 7d35b9298539d2818c51fe9070b08cf9876016f4 / . / drivers / usb / core / hub.c
blob: 63ee3d97b6a968571bc1b706bd3e0cc4169f885c [file] [log] [blame]
/*
* 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>
#ifdef CONFIG_USB_DEBUG
#define DEBUG
#else
#undef DEBUG
#endif
#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 <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 ->serialize, 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 pid_t khubd_pid = 0; /* PID of khubd */
static DECLARE_COMPLETION(khubd_exited);
/* 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;
/* if hub supports power switching, enable power on each port */
if ((hub->descriptor->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 for power to be enabled */
msleep(hub->descriptor->bPwrOn2PwrGood * 2);
}
static void hub_quiesce(struct usb_hub *hub)
{
/* stop khubd and related activity */
hub->quiescing = 1;
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;
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_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;
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");
le16_to_cpus(&hub->descriptor->wHubCharacteristics);
if (hub->descriptor->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 (hub->descriptor->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 (hub->descriptor->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;
}
switch (hub->descriptor->wHubCharacteristics & HUB_CHAR_TTTT) {
case 0x00:
if (hdev->descriptor.bDeviceProtocol != 0)
dev_dbg(hub_dev, "TT requires at most 8 FS bit times\n");
break;
case 0x20:
dev_dbg(hub_dev, "TT requires at most 16 FS bit times\n");
break;
case 0x40:
dev_dbg(hub_dev, "TT requires at most 24 FS bit times\n");
break;
case 0x60:
dev_dbg(hub_dev, "TT requires at most 32 FS bit times\n");
break;
}
/* probe() zeroes hub->indicator[] */
if (hub->descriptor->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 < 0) {
message = "can't get hub status";
goto fail;
}
le16_to_cpus(&hubstatus);
if (hdev == hdev->bus->root_hub) {
struct usb_hcd *hcd =
container_of(hdev->bus, struct usb_hcd, self);
hub->power_budget = min(500u, hcd->power_budget) / 2;
} else if ((hubstatus & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
dev_dbg(hub_dev, "hub controller current requirement: %dmA\n",
hub->descriptor->bHubContrCurrent);
hub->power_budget = (501 - hub->descriptor->bHubContrCurrent)
/ 2;
}
if (hub->power_budget)
dev_dbg(hub_dev, "%dmA bus power budget for children\n",
hub->power_budget * 2);
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 ((hub->descriptor->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;
if (!hub)
return;
hdev = hub->hdev;
if (hdev->speed == USB_SPEED_HIGH)
highspeed_hubs--;
usb_set_intfdata (intf, NULL);
hub_quiesce(hub);
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;
}
/* Free the memory */
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 = kmalloc(sizeof(*hub), GFP_KERNEL);
if (!hub) {
dev_dbg (&intf->dev, "couldn't kmalloc hub struct\n");
return -ENOMEM;
}
memset(hub, 0, sizeof(*hub));
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;
}
}
/* caller has locked the hub device */
static void hub_pre_reset(struct usb_hub *hub)
{
struct usb_device *hdev = hub->hdev;
int i;
for (i = 0; i < hdev->maxchild; ++i) {
if (hdev->children[i])
usb_disconnect(&hdev->children[i]);
}
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);
}
/* 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;
for (t = 0; t < hdev->maxchild; t++) {
if (hdev->children[t] == udev) {
/* everything is fail-fast once disconnect
* processing starts
*/
if (udev->state == USB_STATE_NOTATTACHED)
break;
/* when everyone grabs locks top->bottom,
* non-overlapping work may be concurrent
*/
down(&udev->serialize);
up(&hdev->serialize);
return t + 1;
}
}
usb_unlock_device(hdev);
return -ENODEV;
}
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;
else
recursively_mark_NOTATTACHED(udev);
spin_unlock_irqrestore(&device_state_lock, flags);
}
EXPORT_SYMBOL(usb_set_device_state);
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);
/* lock the bus list on behalf of HCDs unregistering their root hubs */
if (!udev->parent) {
down(&usb_bus_list_lock);
usb_lock_device(udev);
} else
down(&udev->serialize);
dev_info (&udev->dev, "USB disconnect, address %d\n", udev->devnum);
/* 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);
/* 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);
usbfs_remove_device(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);
if (!udev->parent) {
usb_unlock_device(udev);
up(&usb_bus_list_lock);
} else
up(&udev->serialize);
device_unregister(&udev->dev);
}
static int choose_configuration(struct usb_device *udev)
{
int c, i;
/* NOTE: this should interact with hub power budgeting */
c = udev->config[0].desc.bConfigurationValue;
if (udev->descriptor.bNumConfigurations != 1) {
for (i = 0; i < udev->descriptor.bNumConfigurations; i++) {
struct usb_interface_descriptor *desc;
/* heuristic: Linux is more likely to have class
* drivers, so avoid vendor-specific interfaces.
*/
desc = &udev->config[i].intf_cache[0]
->altsetting->desc;
if (desc->bInterfaceClass == USB_CLASS_VENDOR_SPEC)
continue;
/* COMM/2/all is CDC ACM, except 0xff is MSFT RNDIS.
* MSFT needs this to be the first config; never use
* it as the default unless Linux has host-side RNDIS.
* A second config would ideally be CDC-Ethernet, but
* may instead be the "vendor specific" CDC subset
* long used by ARM Linux for sa1100 or pxa255.
*/
if (desc->bInterfaceClass == USB_CLASS_COMM
&& desc->bInterfaceSubClass == 2
&& desc->bInterfaceProtocol == 0xff) {
c = udev->config[1].desc.bConfigurationValue;
continue;
}
c = udev->config[i].desc.bConfigurationValue;
break;
}
dev_info(&udev->dev,
"configuration #%d chosen from %d choices\n",
c, udev->descriptor.bNumConfigurations);
}
return c;
}
#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
static void get_string(struct usb_device *udev, char **string, int index)
{
char *buf;
if (!index)
return;
buf = kmalloc(256, GFP_KERNEL);
if (!buf)
return;
if (usb_string(udev, index, buf, 256) > 0)
*string = buf;
else
kfree(buf);
}
#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 udev and
* 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 should ever call this; root hub registration
* uses it indirectly.
*/
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 */
get_string(udev, &udev->product, udev->descriptor.iProduct);
get_string(udev, &udev->manufacturer, udev->descriptor.iManufacturer);
get_string(udev, &udev->serial, 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;
struct usb_device *root = udev->parent;
for (port1 = 1; port1 <= root->maxchild;
port1++) {
if (root->children[port1-1] == udev)
break;
}
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, pm_message_t state);
err = __usb_suspend_device(udev,
udev->bus->otg_port,
PMSG_SUSPEND);
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);
/* 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)
dev_warn(&udev->dev,
"can't choose an initial configuration\n");
else {
err = usb_set_configuration(udev, c);
if (err) {
dev_err(&udev->dev, "can't set config #%d, error %d\n",
c, err);
usb_remove_sysfs_dev_files(udev);
device_del(&udev->dev);
goto fail;
}
}
/* USB device state == configured ... usable */
/* add a /proc/bus/usb entry */
usbfs_add_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)
dev_dbg(hub->intfdev,
"port_wait_reset: err = %d\n",
status);
}
/* return on disconnect or reset */
switch (status) {
case 0:
/* TRSTRCY = 10 ms */
msleep(10);
/* 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;
}
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;
}
/*
* 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
* - usb_suspend_device(dev, PMSG_SUSPEND)
* 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 (udev->actconfig
// && FIXME (remote wakeup enabled on this bus)
// ... currently assuming it's always appropriate
&& (udev->actconfig->desc.bmAttributes
& USB_CONFIG_ATT_WAKEUP) != 0) {
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.
*/
static int __usb_suspend_device (struct usb_device *udev, int port1,
pm_message_t state)
{
int status;
/* caller owns the udev device lock */
if (port1 < 0)
return port1;
if (udev->state == USB_STATE_SUSPENDED
|| udev->state == USB_STATE_NOTATTACHED) {
return 0;
}
/* suspend interface drivers; if this is a hub, it
* suspends the child devices
*/
if (udev->actconfig) {
int i;
for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
struct usb_interface *intf;
struct usb_driver *driver;
intf = udev->actconfig->interface[i];
if (state <= intf->dev.power.power_state)
continue;
if (!intf->dev.driver)
continue;
driver = to_usb_driver(intf->dev.driver);
if (driver->suspend) {
status = driver->suspend(intf, state);
if (intf->dev.power.power_state != state
|| status)
dev_err(&intf->dev,
"suspend %d fail, code %d\n",
state, status);
}
/* only drivers with suspend() can ever resume();
* and after power loss, even they won't.
* bus_rescan_devices() can rebind drivers later.
*
* FIXME the PM core self-deadlocks when unbinding
* drivers during suspend/resume ... everything grabs
* dpm_sem (not a spinlock, ugh). we want to unbind,
* since we know every driver's probe/disconnect works
* even for drivers that can't suspend.
*/
if (!driver->suspend || state > PM_SUSPEND_MEM) {
#if 1
dev_warn(&intf->dev, "resume is unsafe!\n");
#else
down_write(&usb_bus_type.rwsem);
device_release_driver(&intf->dev);
up_write(&usb_bus_type.rwsem);
#endif
}
}
}
/*
* FIXME this needs port power off call paths too, to help force
* USB into the "generic" PM model. At least for devices on
* ports that aren't using ganged switching (usually root hubs).
*
* NOTE: SRP-capable links should adopt more aggressive poweroff
* policies (when HNP doesn't apply) once we have mechanisms to
* turn power back on! (Likely not before 2.7...)
*/
if (state > PM_SUSPEND_MEM) {
dev_warn(&udev->dev, "no poweroff yet, suspending instead\n");
}
/* "global suspend" of the HC-to-USB interface (root hub), or
* "selective suspend" of just one hub-device link.
*/
if (!udev->parent) {
struct usb_bus *bus = udev->bus;
if (bus && bus->op->hub_suspend) {
status = bus->op->hub_suspend (bus);
if (status == 0) {
dev_dbg(&udev->dev, "usb suspend\n");
usb_set_device_state(udev,
USB_STATE_SUSPENDED);
}
} else
status = -EOPNOTSUPP;
} else
status = hub_port_suspend(hdev_to_hub(udev->parent), port1,
udev);
if (status == 0)
udev->dev.power.power_state = state;
return status;
}
/**
* usb_suspend_device - suspend a usb device
* @udev: device that's no longer in active use
* @state: PMSG_SUSPEND to suspend
* Context: must be able to sleep; device not locked
*
* 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.
*
* 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, pm_message_t state)
{
int port1, status;
port1 = locktree(udev);
if (port1 < 0)
return port1;
status = __usb_suspend_device(udev, port1, state);
usb_unlock_device(udev);
return status;
}
/*
* 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_port_resume(struct usb_device *udev)
{
int status;
u16 devstatus;
/* caller owns the udev device lock */
dev_dbg(&udev->dev, "usb 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 < 0)
dev_dbg(&udev->dev,
"gone after usb resume? status %d\n",
status);
else if (udev->actconfig) {
unsigned i;
le16_to_cpus(&devstatus);
if (devstatus & (1 << USB_DEVICE_REMOTE_WAKEUP)) {
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
* resumes the child devices
*/
for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
struct usb_interface *intf;
struct usb_driver *driver;
intf = udev->actconfig->interface[i];
if (intf->dev.power.power_state == PMSG_SUSPEND)
continue;
if (!intf->dev.driver) {
/* FIXME maybe force to alt 0 */
continue;
}
driver = to_usb_driver(intf->dev.driver);
/* bus_rescan_devices() may rebind drivers */
if (!driver->resume)
continue;
/* can we do better than just logging errors? */
status = driver->resume(intf);
if (intf->dev.power.power_state != PMSG_ON
|| status)
dev_dbg(&intf->dev,
"resume fail, state %d code %d\n",
intf->dev.power.power_state, status);
}
status = 0;
} else if (udev->devnum <= 0) {
dev_dbg(&udev->dev, "bogus resume!\n");
status = -EINVAL;
}
return status;
}
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_port_resume(udev);
}
}
if (status < 0)
hub_port_logical_disconnect(hub, port1);
return status;
}
static int hub_resume (struct usb_interface *intf);
/**
* usb_resume_device - re-activate a suspended usb device
* @udev: device to re-activate
* Context: must be able to sleep; device not locked
*
* 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 port1, status;
port1 = locktree(udev);
if (port1 < 0)
return port1;
/* "global resume" of the HC-to-USB interface (root hub), or
* selective resume of one hub-to-device port
*/
if (!udev->parent) {
struct usb_bus *bus = udev->bus;
if (bus && bus->op->hub_resume) {
status = bus->op->hub_resume (bus);
} else
status = -EOPNOTSUPP;
if (status == 0) {
dev_dbg(&udev->dev, "usb resume\n");
/* TRSMRCY = 10 msec */
msleep(10);
usb_set_device_state (udev, USB_STATE_CONFIGURED);
udev->dev.power.power_state = PMSG_ON;
status = hub_resume (udev
->actconfig->interface[0]);
}
} else if (udev->state == USB_STATE_SUSPENDED) {
// NOTE this fails if parent is also suspended...
status = hub_port_resume(hdev_to_hub(udev->parent),
port1, udev);
} else {
status = 0;
}
if (status < 0) {
dev_dbg(&udev->dev, "can't resume, status %d\n",
status);
}
usb_unlock_device(udev);
/* rebind drivers that had no suspend() */
if (status == 0) {
usb_lock_all_devices();
bus_rescan_devices(&usb_bus_type);
usb_unlock_all_devices();
}
return status;
}
static int remote_wakeup(struct usb_device *udev)
{
int status = 0;
/* don't repeat RESUME sequence if this device
* was already woken up by some other task
*/
down(&udev->serialize);
if (udev->state == USB_STATE_SUSPENDED) {
dev_dbg(&udev->dev, "RESUME (wakeup)\n");
/* TRSMRCY = 10 msec */
msleep(10);
status = finish_port_resume(udev);
}
up(&udev->serialize);
return status;
}
static int hub_suspend(struct usb_interface *intf, pm_message_t state)
{
struct usb_hub *hub = usb_get_intfdata (intf);
struct usb_device *hdev = hub->hdev;
unsigned port1;
int status;
/* stop khubd and related activity */
hub_quiesce(hub);
/* then suspend every port */
for (port1 = 1; port1 <= hdev->maxchild; port1++) {
struct usb_device *udev;
udev = hdev->children [port1-1];
if (!udev)
continue;
down(&udev->serialize);
status = __usb_suspend_device(udev, port1, state);
up(&udev->serialize);
if (status < 0)
dev_dbg(&intf->dev, "suspend port %d --> %d\n",
port1, status);
}
intf->dev.power.power_state = state;
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);
unsigned port1;
int status;
if (intf->dev.power.power_state == PM_SUSPEND_ON)
return 0;
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;
down (&udev->serialize);
if (portstat & USB_PORT_STAT_SUSPEND)
status = hub_port_resume(hub, port1, udev);
else {
status = finish_port_resume(udev);
if (status < 0) {
dev_dbg(&intf->dev, "resume port %d --> %d\n",
port1, status);
hub_port_logical_disconnect(hub, port1);
}
}
up(&udev->serialize);
}
intf->dev.power.power_state = PMSG_ON;
hub->resume_root_hub = 0;
hub_activate(hub);
return 0;
}
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);
}
#else /* !CONFIG_USB_SUSPEND */
int usb_suspend_device(struct usb_device *udev, pm_message_t state)
{
return 0;
}
int usb_resume_device(struct usb_device *udev)
{
return 0;
}
#define hub_suspend NULL
#define hub_resume NULL
#define remote_wakeup(x) 0
#endif /* CONFIG_USB_SUSPEND */
EXPORT_SYMBOL(usb_suspend_device);
EXPORT_SYMBOL(usb_resume_device);
/* 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;
unsigned i;
remaining = hub->power_budget;
if (!remaining) /* self-powered */
return 0;
for (i = 0; i < hdev->maxchild; i++) {
struct usb_device *udev = hdev->children[i];
int delta, ceiling;
if (!udev)
continue;
/* 100mA per-port ceiling, or 8mA for OTG ports */
if (i != (udev->bus->otg_port - 1) || hdev->parent)
ceiling = 50;
else
ceiling = 4;
if (udev->actconfig)
delta = udev->actconfig->desc.bMaxPower;
else
delta = ceiling;
// dev_dbg(&udev->dev, "budgeted %dmA\n", 2 * delta);
if (delta > ceiling)
dev_warn(&udev->dev, "%dmA over %dmA budget!\n",
2 * (delta - ceiling), 2 * ceiling);
remaining -= delta;
}
if (remaining < 0) {
dev_warn(hub->intfdev,
"%dmA over power budget!\n",
-2 * 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;
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 ((hub->descriptor->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;
/* 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
&& hub->power_budget) {
u16 devstat;
status = usb_get_status(udev, USB_RECIP_DEVICE, 0,
&devstat);
if (status < 0) {
dev_dbg(&udev->dev, "get status %d ?\n", status);
goto loop_disable;
}
cpu_to_le16s(&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.
*/
down (&udev->serialize);
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);
}
}
up (&udev->serialize);
if (status)
goto loop_disable;
status = hub_power_remaining(hub);
if (status)
dev_dbg(hub_dev,
"%dmA power budget left\n",
2 * 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;
dev_dbg(hub_dev, "state %d ports %d chg %04x evt %04x\n",
hdev->state, hub->descriptor
? hub->descriptor->bNbrPorts
: 0,
/* NOTE: expects max 15 ports... */
(u16) hub->change_bits[0],
(u16) hub->event_bits[0]);
usb_get_intf(intf);
i = hub->resume_root_hub;
spin_unlock_irq(&hub_event_lock);
/* Is this is a root hub wanting to be resumed? */
if (i)
usb_resume_device(hdev);
/* 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);
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 (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)
{
/*
* This thread doesn't need any user-level access,
* so get rid of all our resources
*/
daemonize("khubd");
allow_signal(SIGKILL);
/* Send me a signal to get me die (for debugging) */
do {
hub_events();
wait_event_interruptible(khubd_wait, !list_empty(&hub_event_list));
try_to_freeze();
} while (!signal_pending(current));
pr_debug ("%s: khubd exiting\n", usbcore_name);
complete_and_exit(&khubd_exited, 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 = {
.owner = THIS_MODULE,
.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)
{
pid_t pid;
if (usb_register(&hub_driver) < 0) {
printk(KERN_ERR "%s: can't register hub driver\n",
usbcore_name);
return -1;
}
pid = kernel_thread(hub_thread, NULL, CLONE_KERNEL);
if (pid >= 0) {
khubd_pid = pid;
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)
{
int ret;
/* Kill the thread */
ret = kill_proc(khubd_pid, SIGKILL, 1);
wait_for_completion(&khubd_exited);
/*
* 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, port1 = -1;
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;
}
for (i = 0; i < parent_hdev->maxchild; i++)
if (parent_hdev->children[i] == udev) {
port1 = i + 1;
break;
}
if (port1 < 0) {
/* If this ever happens, it's very bad */
dev_err(&udev->dev, "Can't locate device's port!\n");
return -ENOENT;
}
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);
}
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;
}