diff options
| author | Sarah Sharp <sarah.a.sharp@linux.intel.com> | 2012-10-04 09:53:43 -0700 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2012-10-28 10:56:14 -0700 |
| commit | 094c5b6410392321492c59603879f8ec7d87358a (patch) | |
| tree | 693386a5229b281a7f3f74bc71987e8895f817cb /drivers | |
| parent | 6a154bb60bfcbc91b515a94ee68e35c3b4b01b7c (diff) | |
USB: Enable LPM after a failed probe.
commit d01f87c0ffa96cb44faa78710711eb6e974b891c upstream.
Before a driver is probed, we want to disable USB 3.0 Link Power
Management (LPM), in case the driver needs hub-initiated LPM disabled.
After the probe finishes, we want to attempt to re-enable LPM, order to
balance the LPM ref count.
When a probe fails (such as when libusual doesn't want to bind to a USB
3.0 mass storage device), make sure to balance the LPM ref counts by
re-enabling LPM.
This patch 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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/usb/core/driver.c | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/drivers/usb/core/driver.c b/drivers/usb/core/driver.c index 445455a4429..fb6e97f5278 100644 --- a/drivers/usb/core/driver.c +++ b/drivers/usb/core/driver.c @@ -372,6 +372,10 @@ static int usb_probe_interface(struct device *dev) intf->condition = USB_INTERFACE_UNBOUND; usb_cancel_queued_reset(intf); + /* If the LPM disable succeeded, balance the ref counts. */ + if (!lpm_disable_error) + usb_unlocked_enable_lpm(udev); + /* Unbound interfaces are always runtime-PM-disabled and -suspended */ if (driver->supports_autosuspend) pm_runtime_disable(dev); |