USB: handle errors in power/level attribute
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 <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/drivers/usb/core/sysfs.c b/drivers/usb/core/sysfs.c
index e7c9823..be37c86 100644
--- a/drivers/usb/core/sysfs.c
+++ b/drivers/usb/core/sysfs.c
@@ -232,12 +232,15 @@
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 @@
} 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);
}