USB: cdc-wdm: reset handling according to new requirements

This patch
- ensures no IO takes place during resets
- reports resets to user space

Signed-off-by: Oliver Neukum <oneukum@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 14 insertions, 0 deletions

diff --git a/drivers/usb/class/cdc-wdm.c b/drivers/usb/class/cdc-wdm.c
index a97c018dd419..2b9ff518b509 100644
--- a/drivers/usb/class/cdc-wdm.c
+++ b/drivers/usb/class/cdc-wdm.c
@@ -542,6 +542,8 @@ static int wdm_open(struct inode *inode, struct file *file)
 
         mutex_lock(&desc->lock);
         if (!desc->count++) {
+                desc->werr = 0;
+                desc->rerr = 0;
                 rv = usb_submit_urb(desc->validity, GFP_KERNEL);
                 if (rv < 0) {
                         desc->count--;
@@ -853,6 +855,18 @@ static int wdm_pre_reset(struct usb_interface *intf)
         struct wdm_device *desc = usb_get_intfdata(intf);
 
         mutex_lock(&desc->lock);
+        kill_urbs(desc);
+
+        /*
+         * we notify everybody using poll of
+         * an exceptional situation
+         * must be done before recovery lest a spontaneous
+         * message from the device is lost
+         */
+        spin_lock_irq(&desc->iuspin);
+        desc->rerr = -EINTR;
+        spin_unlock_irq(&desc->iuspin);
+        wake_up_all(&desc->wait);
         return 0;
 }