diff options
| author | Tilman Schmidt <tilman@imap.cc> | 2012-10-24 08:44:32 +0000 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2012-10-26 02:20:36 -0400 |
| commit | c6fdd8e5d0c65bb8821dc6da26ee1a2ddd58b3cc (patch) | |
| tree | 3a7b4adf2480e45fdc07702d2708291a496a7c9b | |
| parent | 910a578f7e9400a78a3b13aba0b4d2df16a2cb05 (diff) | |
bas_gigaset: fix pre_reset handling
The delayed work function int_in_work() may call usb_reset_device()
and thus, indirectly, the driver's pre_reset method. Trying to
cancel the work synchronously in that situation would deadlock.
Fix by avoiding cancel_work_sync() in the pre_reset method.
If the reset was NOT initiated by int_in_work() this might cause
int_in_work() to run after the post_reset method, with urb_int_in
already resubmitted, so handle that case gracefully.
Signed-off-by: Tilman Schmidt <tilman@imap.cc>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | drivers/isdn/gigaset/bas-gigaset.c | 19 |
1 files changed, 16 insertions, 3 deletions
diff --git a/drivers/isdn/gigaset/bas-gigaset.c b/drivers/isdn/gigaset/bas-gigaset.c index 527588708948..c44950d3eb7b 100644 --- a/drivers/isdn/gigaset/bas-gigaset.c +++ b/drivers/isdn/gigaset/bas-gigaset.c @@ -617,7 +617,13 @@ static void int_in_work(struct work_struct *work) if (rc == 0) /* success, resubmit interrupt read URB */ rc = usb_submit_urb(urb, GFP_ATOMIC); - if (rc != 0 && rc != -ENODEV) { + + switch (rc) { + case 0: /* success */ + case -ENODEV: /* device gone */ + case -EINVAL: /* URB already resubmitted, or terminal badness */ + break; + default: /* failure: try to recover by resetting the device */ dev_err(cs->dev, "clear halt failed: %s\n", get_usb_rcmsg(rc)); rc = usb_lock_device_for_reset(ucs->udev, ucs->interface); if (rc == 0) { @@ -2442,7 +2448,9 @@ static void gigaset_disconnect(struct usb_interface *interface) } /* gigaset_suspend - * This function is called before the USB connection is suspended. + * This function is called before the USB connection is suspended + * or before the USB device is reset. + * In the latter case, message == PMSG_ON. */ static int gigaset_suspend(struct usb_interface *intf, pm_message_t message) { @@ -2498,7 +2506,12 @@ static int gigaset_suspend(struct usb_interface *intf, pm_message_t message) del_timer_sync(&ucs->timer_atrdy); del_timer_sync(&ucs->timer_cmd_in); del_timer_sync(&ucs->timer_int_in); - cancel_work_sync(&ucs->int_in_wq); + + /* don't try to cancel int_in_wq from within reset as it + * might be the one requesting the reset + */ + if (message.event != PM_EVENT_ON) + cancel_work_sync(&ucs->int_in_wq); gig_dbg(DEBUG_SUSPEND, "suspend complete"); return 0; |