From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Greg Kroah-Hartman , alan@lxorguk.ukuu.org.uk, Oliver Neukum , Alan Stern Subject: [ 178/221] USB: hub: handle claim of enabled remote wakeup after reset Date: Tue, 15 Jan 2013 10:51:45 -0800 Message-Id: <20130115185010.880210531@linuxfoundation.org> In-Reply-To: <20130115184958.025580322@linuxfoundation.org> References: <20130115184958.025580322@linuxfoundation.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: 3.7-stable review patch. If anyone has any objections, please let me know. ------------------ From: Oliver Neukum 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 --- drivers/usb/core/hub.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) --- a/drivers/usb/core/hub.c +++ b/drivers/usb/core/hub.c @@ -2960,7 +2960,7 @@ int usb_port_suspend(struct usb_device * 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", @@ -3005,7 +3005,13 @@ static int finish_port_resume(struct usb 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,