[PATCH 52/74] USB: hub: handle claim of enabled remote wakeup after reset
From: Herton Ronaldo Krzesinski <hidden>
Date: 2013-01-24 03:36:59
Also in:
lkml
Subsystem:
the rest, usb subsystem · Maintainers:
Linus Torvalds, Greg Kroah-Hartman
3.5.7.4 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Oliver Neukum <oliver@neukum.org> 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 <redacted> Acked-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Herton Ronaldo Krzesinski <redacted> --- drivers/usb/core/hub.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-)
diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c
index 2532bdc..92c0229 100644
--- a/drivers/usb/core/hub.c
+++ b/drivers/usb/core/hub.c@@ -2840,7 +2840,7 @@ 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",
@@ -2885,7 +2885,13 @@ 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,
--
1.7.9.5