Some touchscreens have buggy firmware which claims
remote wakeup to be enabled after a reset. They nevertheless
crash if the feature is cleared by the host.
Add a check for reset resume before checking for
an enabled remote wakeup feature. On compliant
devices the feature must be cleared after a reset anyway.
Signed-off-by: Oliver Neukum <oneukum@xxxxxxx>
---
drivers/usb/core/hub.c | 10 ++++++++--
1 files changed, 8 insertions(+), 2 deletions(-)
diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c
index 1af04bd..ded05b0 100644
--- a/drivers/usb/core/hub.c
+++ b/drivers/usb/core/hub.c
@@ -2899,7 +2899,7 @@ int usb_port_suspend(struct usb_device *udev, pm_message_t msg)
static int finish_port_resume(struct usb_device *udev)
{
int status = 0;
- u16 devstatus;
+ u16 devstatus = 0;
/* caller owns the udev device lock */
dev_dbg(&udev->dev, "%s\n",
@@ -2944,7 +2944,13 @@ static int finish_port_resume(struct usb_device *udev)
if (status) {
dev_dbg(&udev->dev, "gone after usb resume? status %d\n",
status);
- } else if (udev->actconfig) {
+ /*
+ * There are a few quirky devices which violate the standard
+ * by claiming to have remote wakeup enabled after a reset,
+ * which crash if the feature is cleared, hence check for
+ * udev->reset_resume
+ */
+ } else if (udev->actconfig && !udev->reset_resume) {
le16_to_cpus(&devstatus);
if (devstatus & (1 << USB_DEVICE_REMOTE_WAKEUP)) {
status = usb_control_msg(udev,
--
1.7.7
--
To unsubscribe from this list: send the line "unsubscribe linux-usb" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
