USB: autosuspend for usb printer driver

this implements autosuspend for usb printers. It compiles and is tested.

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

1 files changed, 5 insertions, 11 deletions

diff --git a/drivers/usb/class/usblp.c b/drivers/usb/class/usblp.c
index 6377db1b446d..63e50a1f1396 100644
--- a/drivers/usb/class/usblp.c
+++ b/drivers/usb/class/usblp.c
@@ -398,6 +398,9 @@ static int usblp_open(struct inode *inode, struct file *file)
         retval = 0;
 #endif
 
+        retval = usb_autopm_get_interface(intf);
+        if (retval < 0)
+                goto out;
         usblp->used = 1;
         file->private_data = usblp;
 
@@ -442,6 +445,7 @@ static int usblp_release(struct inode *inode, struct file *file)
         usblp->used = 0;
         if (usblp->present) {
                 usblp_unlink_urbs(usblp);
+                usb_autopm_put_interface(usblp->intf);
         } else          /* finish cleanup from disconnect */
                 usblp_cleanup (usblp);
         mutex_unlock (&usblp_mutex);
@@ -1203,14 +1207,9 @@ static int usblp_suspend (struct usb_interface *intf, pm_message_t message)
 {
         struct usblp *usblp = usb_get_intfdata (intf);
 
-        /* this races against normal access and open */
-        mutex_lock (&usblp_mutex);
-        mutex_lock (&usblp->mut);
         /* we take no more IO */
         usblp->sleeping = 1;
         usblp_unlink_urbs(usblp);
-        mutex_unlock (&usblp->mut);
-        mutex_unlock (&usblp_mutex);
 
         return 0;
 }
@@ -1220,15 +1219,9 @@ static int usblp_resume (struct usb_interface *intf)
         struct usblp *usblp = usb_get_intfdata (intf);
         int r;
 
-        mutex_lock (&usblp_mutex);
-        mutex_lock (&usblp->mut);
-
         usblp->sleeping = 0;
         r = handle_bidir (usblp);
 
-        mutex_unlock (&usblp->mut);
-        mutex_unlock (&usblp_mutex);
-
         return r;
 }
 
@@ -1251,6 +1244,7 @@ static struct usb_driver usblp_driver = {
         .suspend =      usblp_suspend,
         .resume =       usblp_resume,
         .id_table =     usblp_ids,
+        .supports_autosuspend = 1,
 };
 
 static int __init usblp_init(void)