diff options
| author | Thomas Pugliese <thomas.pugliese@gmail.com> | 2013-06-24 19:26:35 (GMT) |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2013-06-24 23:20:43 (GMT) |
| commit | a899575191ba85a71401f2c8f36bec7b14487043 (patch) | |
| tree | 74070049b20ec44cf625db68ac62751e4b33cab0 /drivers/usb/wusbcore/pal.c | |
| parent | 6e6581e0a94758a4e69fab82407d39312eeff5c4 (diff) | |
| download | linux-fsl-qoriq-a899575191ba85a71401f2c8f36bec7b14487043.tar.xz | |
USB: HWA: fix device probe failure
This patch fixes a race condition that caused the HWA_HC interface probe
function to occasionally fail. The HWA_HC would attempt to register
itself with the HWA_RC by searching for a uwb_rc class device with the
same parent device ptr. If the probe function for the HWA_RC interface
had yet to run, the uwb_rc class device would not have been created
causing the look up to fail and the HWA_HC probe function to return an
error causing the device to be unusable.
The fix is for the HWA to delay registering with the HWA_RC until
receiving the command from userspace to start the wireless channel. It
is the responsibility of userspace to ensure that the uwb_rc class
device has been created before starting the HWA channel.
Signed-off-by: Thomas Pugliese <thomas.pugliese@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/usb/wusbcore/pal.c')
| -rw-r--r-- | drivers/usb/wusbcore/pal.c | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/drivers/usb/wusbcore/pal.c b/drivers/usb/wusbcore/pal.c index d0b172c..59e100c 100644 --- a/drivers/usb/wusbcore/pal.c +++ b/drivers/usb/wusbcore/pal.c @@ -45,10 +45,11 @@ int wusbhc_pal_register(struct wusbhc *wusbhc) } /** - * wusbhc_pal_register - unregister the WUSB HC as a UWB PAL + * wusbhc_pal_unregister - unregister the WUSB HC as a UWB PAL * @wusbhc: the WUSB HC */ void wusbhc_pal_unregister(struct wusbhc *wusbhc) { - uwb_pal_unregister(&wusbhc->pal); + if (wusbhc->uwb_rc) + uwb_pal_unregister(&wusbhc->pal); } |