diff options
| author | Sarah Sharp <sarah.a.sharp@linux.intel.com> | 2012-07-03 23:22:38 -0700 |
|---|---|---|
| committer | Sarah Sharp <sarah.a.sharp@linux.intel.com> | 2012-07-11 07:06:46 -0400 |
| commit | 9cf65991dd93ac3d5f97f536171c388918b7c1a9 (patch) | |
| tree | 06d01607f5667fe43cca031bbeef94bd2cfec5ec /drivers/usb/core/message.c | |
| parent | 6d1d051330ee096f575523647fbd8ffe703600b5 (diff) | |
| download | talos-obmc-linux-9cf65991dd93ac3d5f97f536171c388918b7c1a9.tar.gz talos-obmc-linux-9cf65991dd93ac3d5f97f536171c388918b7c1a9.zip | |
USB: Disable LPM while the device is unconfigured.
The USB 3.0 Set/Clear Feature U1/U2 Enable cannot be sent to a device in
the Default or Addressed state. It can only be sent to a configured
device. Change the USB core to initialize the LPM disable count to 1
(disabled), which reflects this limitation.
Change usb_set_configuration() to ensure that if the device is
unconfigured on entry, usb_lpm_disable() is not called. This avoids
sending the Clear Feature U1/U2 when the device is in the Addressed
state. When usb_set_configuration() exits with a successfully installed
configuration, usb_lpm_enable() will be called.
Once the new configuration is installed, make sure
usb_set_configuration() only calls usb_enable_lpm() if the device moved
to the Configured state. If we have unconfigured the device by sending
it a Set Configuration for config 0, don't enable LPM.
This commit should be backported to kernels as old as 3.5, that contain
the commit 8306095fd2c1100e8244c09bf560f97aca5a311d "USB: Disable USB
3.0 LPM in critical sections."
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Cc: stable@vger.kernel.org
Diffstat (limited to 'drivers/usb/core/message.c')
| -rw-r--r-- | drivers/usb/core/message.c | 7 |
1 files changed, 4 insertions, 3 deletions
diff --git a/drivers/usb/core/message.c b/drivers/usb/core/message.c index 8b9d669e3784..37239048be14 100644 --- a/drivers/usb/core/message.c +++ b/drivers/usb/core/message.c @@ -1792,14 +1792,15 @@ free_interfaces: * installed, so that the xHCI driver can recalculate the U1/U2 * timeouts. */ - if (usb_disable_lpm(dev)) { + if (dev->actconfig && usb_disable_lpm(dev)) { dev_err(&dev->dev, "%s Failed to disable LPM\n.", __func__); mutex_unlock(hcd->bandwidth_mutex); return -ENOMEM; } ret = usb_hcd_alloc_bandwidth(dev, cp, NULL, NULL); if (ret < 0) { - usb_enable_lpm(dev); + if (dev->actconfig) + usb_enable_lpm(dev); mutex_unlock(hcd->bandwidth_mutex); usb_autosuspend_device(dev); goto free_interfaces; @@ -1819,7 +1820,7 @@ free_interfaces: if (!cp) { usb_set_device_state(dev, USB_STATE_ADDRESS); usb_hcd_alloc_bandwidth(dev, NULL, NULL, NULL); - usb_enable_lpm(dev); + /* Leave LPM disabled while the device is unconfigured. */ mutex_unlock(hcd->bandwidth_mutex); usb_autosuspend_device(dev); goto free_interfaces; |
