Re: [linux-pm] 2.6.27-rc2 USB suspend regression

From: Oliver Neukum
Date: Thu Aug 28 2008 - 03:13:09 EST


Am Mittwoch 27 August 2008 23:36:30 schrieb Jeremy Fitzhardinge:
> > Is this still a problem?
> >  
>
> I haven't seen it lately, but it was fairly erratic anyway.  It happened
> a few times in quick succession, and then it all worked fine.  The
> rawhide kernels are getting fairly old (I guess RH is still trying to
> pull its infrastructure together), so I'm running a fairly recent
> self-compiled kernel.  Will report anything I see.
>
> > Is this related to other Bluetooth suspend/resume regressions in
> > 2.6.27?
> >  
>
> I'm not sure if its BT or Sierra wireless related.

The attached patch is reported to make the problem go away for
a user of btusb. He might be able to use it for narrowing down causes.

Regards
Oliver

--- linux-2.6.27-rc4/drivers/usb/core/urb.c 2008-08-21 10:03:44.000000000 +0200
+++ linux-2.6.27-rc3/drivers/usb/core/urb.c 2008-08-22 17:25:49.000000000 +0200
@@ -601,15 +601,20 @@ EXPORT_SYMBOL_GPL(usb_kill_anchored_urbs
void usb_unlink_anchored_urbs(struct usb_anchor *anchor)
{
struct urb *victim;
+ unsigned long flags;

- spin_lock_irq(&anchor->lock);
+ spin_lock_irqsave(&anchor->lock, flags);
while (!list_empty(&anchor->urb_list)) {
victim = list_entry(anchor->urb_list.prev, struct urb,
anchor_list);
+ usb_get_urb(victim);
+ spin_unlock_irqrestore(&anchor->lock, flags);
/* this will unanchor the URB */
usb_unlink_urb(victim);
+ usb_put_urb(victim);
+ spin_lock_irqsave(&anchor->lock, flags);
}
- spin_unlock_irq(&anchor->lock);
+ spin_unlock_irqrestore(&anchor->lock, flags);
}
EXPORT_SYMBOL_GPL(usb_unlink_anchored_urbs);

--- linux-2.6.27-rc4/drivers/bluetooth/btusb.c.alt 2008-08-25 15:02:14.000000000 +0200
+++ linux-2.6.27-rc4/drivers/bluetooth/btusb.c 2008-08-25 15:44:25.000000000 +0200
@@ -169,6 +169,7 @@ static struct usb_device_id blacklist_ta
struct btusb_data {
struct hci_dev *hdev;
struct usb_device *udev;
+ struct usb_interface *acl;
struct usb_interface *isoc;

spinlock_t lock;
@@ -176,6 +177,7 @@ struct btusb_data {
unsigned long flags;

struct work_struct work;
+ struct work_struct waker;

struct usb_anchor tx_anchor;
struct usb_anchor intr_anchor;
@@ -189,6 +191,7 @@ struct btusb_data {
struct usb_endpoint_descriptor *isoc_rx_ep;

int isoc_altsetting;
+ int susp_count;
};

static void btusb_intr_complete(struct urb *urb)
@@ -227,7 +230,7 @@ static void btusb_intr_complete(struct u
}
}

-static int btusb_submit_intr_urb(struct hci_dev *hdev)
+static int btusb_submit_intr_urb(struct hci_dev *hdev, gfp_t gfp)
{
struct btusb_data *data = hdev->driver_data;
struct urb *urb;
@@ -240,13 +243,13 @@ static int btusb_submit_intr_urb(struct
if (!data->intr_ep)
return -ENODEV;

- urb = usb_alloc_urb(0, GFP_ATOMIC);
+ urb = usb_alloc_urb(0, gfp);
if (!urb)
return -ENOMEM;

size = le16_to_cpu(data->intr_ep->wMaxPacketSize);

- buf = kmalloc(size, GFP_ATOMIC);
+ buf = kmalloc(size, gfp);
if (!buf) {
usb_free_urb(urb);
return -ENOMEM;
@@ -262,7 +265,7 @@ static int btusb_submit_intr_urb(struct

usb_anchor_urb(urb, &data->intr_anchor);

- err = usb_submit_urb(urb, GFP_ATOMIC);
+ err = usb_submit_urb(urb, gfp);
if (err < 0) {
BT_ERR("%s urb %p submission failed (%d)",
hdev->name, urb, -err);
@@ -311,7 +314,7 @@ static void btusb_bulk_complete(struct u
}
}

-static int btusb_submit_bulk_urb(struct hci_dev *hdev)
+static int btusb_submit_bulk_urb(struct hci_dev *hdev, gfp_t gfp)
{
struct btusb_data *data = hdev->driver_data;
struct urb *urb;
@@ -324,18 +327,19 @@ static int btusb_submit_bulk_urb(struct
if (!data->bulk_rx_ep)
return -ENODEV;

- urb = usb_alloc_urb(0, GFP_KERNEL);
+ urb = usb_alloc_urb(0, gfp);
if (!urb)
return -ENOMEM;

size = le16_to_cpu(data->bulk_rx_ep->wMaxPacketSize);

- buf = kmalloc(size, GFP_KERNEL);
+ buf = kmalloc(size, gfp);
if (!buf) {
usb_free_urb(urb);
return -ENOMEM;
}

+ usb_mark_last_busy(data->udev);
pipe = usb_rcvbulkpipe(data->udev, data->bulk_rx_ep->bEndpointAddress);

usb_fill_bulk_urb(urb, data->udev, pipe,
@@ -345,7 +349,7 @@ static int btusb_submit_bulk_urb(struct

usb_anchor_urb(urb, &data->bulk_anchor);

- err = usb_submit_urb(urb, GFP_KERNEL);
+ err = usb_submit_urb(urb, gfp);
if (err < 0) {
BT_ERR("%s urb %p submission failed (%d)",
hdev->name, urb, -err);
@@ -514,7 +518,7 @@ static int btusb_open(struct hci_dev *hd
if (test_and_set_bit(BTUSB_INTR_RUNNING, &data->flags))
return 0;

- err = btusb_submit_intr_urb(hdev);
+ err = btusb_submit_intr_urb(hdev, GFP_KERNEL);
if (err < 0) {
clear_bit(BTUSB_INTR_RUNNING, &hdev->flags);
clear_bit(HCI_RUNNING, &hdev->flags);
@@ -523,6 +527,13 @@ static int btusb_open(struct hci_dev *hd
return err;
}

+static void btusb_stop_traffic(struct btusb_data *data)
+{
+ usb_kill_anchored_urbs(&data->intr_anchor);
+ usb_kill_anchored_urbs(&data->bulk_anchor);
+ usb_kill_anchored_urbs(&data->isoc_anchor);
+}
+
static int btusb_close(struct hci_dev *hdev)
{
struct btusb_data *data = hdev->driver_data;
@@ -532,14 +543,12 @@ static int btusb_close(struct hci_dev *h
if (!test_and_clear_bit(HCI_RUNNING, &hdev->flags))
return 0;

- clear_bit(BTUSB_ISOC_RUNNING, &data->flags);
- usb_kill_anchored_urbs(&data->intr_anchor);
+ flush_work(&data->work);

+ clear_bit(BTUSB_ISOC_RUNNING, &data->flags);
clear_bit(BTUSB_BULK_RUNNING, &data->flags);
- usb_kill_anchored_urbs(&data->bulk_anchor);
-
clear_bit(BTUSB_INTR_RUNNING, &data->flags);
- usb_kill_anchored_urbs(&data->intr_anchor);
+ btusb_stop_traffic(data);

return 0;
}
@@ -672,8 +681,19 @@ static void btusb_notify(struct hci_dev

BT_DBG("%s evt %d", hdev->name, evt);

- if (evt == HCI_NOTIFY_CONN_ADD || evt == HCI_NOTIFY_CONN_DEL)
- schedule_work(&data->work);
+ if (hdev->conn_hash.acl_num > 0) {
+ if (!test_and_set_bit(BTUSB_BULK_RUNNING, &data->flags)) {
+ if (btusb_submit_bulk_urb(hdev, GFP_ATOMIC) < 0)
+ clear_bit(BTUSB_BULK_RUNNING, &data->flags);
+ else
+ btusb_submit_bulk_urb(hdev, GFP_ATOMIC);
+ }
+ } else {
+ clear_bit(BTUSB_BULK_RUNNING, &data->flags);
+ usb_unlink_anchored_urbs(&data->bulk_anchor);
+ }
+
+ schedule_work(&data->work);
}

static int inline __set_isoc_interface(struct hci_dev *hdev, int altsetting)
@@ -724,18 +744,6 @@ static void btusb_work(struct work_struc
struct btusb_data *data = container_of(work, struct btusb_data, work);
struct hci_dev *hdev = data->hdev;

- if (hdev->conn_hash.acl_num > 0) {
- if (!test_and_set_bit(BTUSB_BULK_RUNNING, &data->flags)) {
- if (btusb_submit_bulk_urb(hdev) < 0)
- clear_bit(BTUSB_BULK_RUNNING, &data->flags);
- else
- btusb_submit_bulk_urb(hdev);
- }
- } else {
- clear_bit(BTUSB_BULK_RUNNING, &data->flags);
- usb_kill_anchored_urbs(&data->bulk_anchor);
- }
-
if (hdev->conn_hash.sco_num > 0) {
if (data->isoc_altsetting != 2) {
clear_bit(BTUSB_ISOC_RUNNING, &data->flags);
@@ -821,6 +829,7 @@ static int btusb_probe(struct usb_interf
}

data->udev = interface_to_usbdev(intf);
+ data->acl = intf;

spin_lock_init(&data->lock);

@@ -889,7 +898,7 @@ static int btusb_probe(struct usb_interf

if (data->isoc) {
err = usb_driver_claim_interface(&btusb_driver,
- data->isoc, NULL);
+ data->isoc, data);
if (err < 0) {
hci_free_dev(hdev);
kfree(data);
@@ -921,20 +930,92 @@ static void btusb_disconnect(struct usb_

hdev = data->hdev;

- if (data->isoc)
- usb_driver_release_interface(&btusb_driver, data->isoc);
+ /* make sure we have a reference */
+ __hci_dev_hold(hdev);

- usb_set_intfdata(intf, NULL);
+ usb_set_intfdata(data->acl, NULL);
+ if (data->isoc)
+ usb_set_intfdata(data->isoc, NULL);

+ /* unregister before releasing any interface */
hci_unregister_dev(hdev);

+ if (intf == data->isoc)
+ usb_driver_release_interface(&btusb_driver, data->acl);
+ else if (data->isoc)
+ usb_driver_release_interface(&btusb_driver, data->isoc);
+
+ /* release the reference */
+ __hci_dev_put(hdev);
hci_free_dev(hdev);
}

+static int btusb_suspend(struct usb_interface *intf, pm_message_t message)
+{
+ struct btusb_data *data = usb_get_intfdata(intf);
+
+ BT_DBG("%s called\n", __func__);
+
+ if (data->susp_count++)
+ return 0;
+
+ cancel_work_sync(&data->work);
+ btusb_stop_traffic(data);
+ usb_kill_anchored_urbs(&data->tx_anchor);
+ return 0;
+}
+
+static int btusb_resume(struct usb_interface *intf)
+{
+ struct btusb_data *data = usb_get_intfdata(intf);
+ struct hci_dev *hdev = data->hdev;
+ int ret;
+
+ if (--data->susp_count)
+ return 0;
+ if (test_bit(HCI_RUNNING, &hdev->flags)) {
+ ret = btusb_submit_intr_urb(hdev, GFP_NOIO);
+ if (ret < 0) {
+ clear_bit(HCI_RUNNING, &hdev->flags);
+ return ret;
+ }
+ }
+
+ if (hdev->conn_hash.acl_num > 0) {
+ ret = btusb_submit_bulk_urb(hdev, GFP_NOIO);
+ if (ret < 0) {
+ clear_bit(BTUSB_BULK_RUNNING, &data->flags);
+ return ret;
+ } else {
+ ret = btusb_submit_bulk_urb(hdev, GFP_NOIO);
+ if (ret < 0) {
+ clear_bit(BTUSB_BULK_RUNNING, &data->flags);
+ usb_kill_anchored_urbs(&data->bulk_anchor);
+ return ret;
+ }
+ }
+ }
+
+ if (data->isoc) {
+ if (test_bit(BTUSB_ISOC_RUNNING, &data->flags)) {
+ ret = btusb_submit_isoc_urb(hdev);
+ if (ret < 0)
+ clear_bit(BTUSB_ISOC_RUNNING, &data->flags);
+ else
+ btusb_submit_isoc_urb(hdev);
+ }
+ }
+
+ schedule_work(&data->work);
+ return 0;
+}
+
static struct usb_driver btusb_driver = {
.name = "btusb",
.probe = btusb_probe,
.disconnect = btusb_disconnect,
+ .suspend = btusb_suspend,
+ .resume = btusb_resume,
.id_table = btusb_table,
};