From: Oliver Neukum Date: Thu, 29 Nov 2012 14:05:57 +0000 (+0100) Subject: USB: hub: handle claim of enabled remote wakeup after reset X-Git-Tag: firefly_0821_release~7541^2~108 X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=b30765e89105c321ed5a5259dc6b05752cbc8137;p=firefly-linux-kernel-4.4.55.git USB: hub: handle claim of enabled remote wakeup after reset commit 07e72b95f5038cc82304b9a4a2eb7f9fc391ea68 upstream. 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 Acked-by: Alan Stern Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c index 0ad69361a4f1..be9cac6e3b9e 100644 --- a/drivers/usb/core/hub.c +++ b/drivers/usb/core/hub.c @@ -2413,7 +2413,7 @@ 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", @@ -2458,7 +2458,13 @@ 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,