From stern@rowland.harvard.edu Tue May 22 09:20:39 2007 From: Alan Stern Date: Tue, 22 May 2007 11:38:19 -0400 (EDT) Subject: USB: handle errors in power/level attribute To: Greg KH Message-ID: From: Alan Stern This patch (as906) improves the error handling for the USB power/level attribute file. If an error occurs, the original power-level settings will be restored. Signed-off-by: Alan Stern Signed-off-by: Greg Kroah-Hartman --- drivers/usb/core/sysfs.c | 7 +++++++ 1 file changed, 7 insertions(+) --- a/drivers/usb/core/sysfs.c +++ b/drivers/usb/core/sysfs.c @@ -232,12 +232,15 @@ set_level(struct device *dev, struct dev int len = count; char *cp; int rc = 0; + int old_autosuspend_disabled, old_autoresume_disabled; cp = memchr(buf, '\n', count); if (cp) len = cp - buf; usb_lock_device(udev); + old_autosuspend_disabled = udev->autosuspend_disabled; + old_autoresume_disabled = udev->autoresume_disabled; /* Setting the flags without calling usb_pm_lock is a subject to * races, but who cares... @@ -263,6 +266,10 @@ set_level(struct device *dev, struct dev } else rc = -EINVAL; + if (rc) { + udev->autosuspend_disabled = old_autosuspend_disabled; + udev->autoresume_disabled = old_autoresume_disabled; + } usb_unlock_device(udev); return (rc < 0 ? rc : count); }