1 files changed, 47 insertions, 20 deletions

diff --git a/drivers/usb/misc/usblcd.c b/drivers/usb/misc/usblcd.c
index 12bad8a205a7..504f7221b0d0 100644
--- a/drivers/usb/misc/usblcd.c
+++ b/drivers/usb/misc/usblcd.c
@@ -45,13 +45,13 @@ struct usb_lcd {
         struct kref             kref;
         struct semaphore        limit_sem;              /* to stop writes at full throttle from
                                                          * using up all RAM */
+        struct usb_anchor       submitted;              /* URBs to wait for before suspend */
 };
 #define to_lcd_dev(d) container_of(d, struct usb_lcd, kref)
 
 #define USB_LCD_CONCURRENT_WRITES       5
 
 static struct usb_driver lcd_driver;
-static DEFINE_MUTEX(usb_lcd_open_mutex);
 
 
 static void lcd_delete(struct kref *kref)
@@ -68,35 +68,35 @@ static int lcd_open(struct inode *inode, struct file *file)
 {
         struct usb_lcd *dev;
         struct usb_interface *interface;
-        int subminor;
-        int retval = 0;
+        int subminor, r;
 
         subminor = iminor(inode);
 
-        mutex_lock(&usb_lcd_open_mutex);
         interface = usb_find_interface(&lcd_driver, subminor);
         if (!interface) {
                 err ("USBLCD: %s - error, can't find device for minor %d",
                      __FUNCTION__, subminor);
-                retval = -ENODEV;
-                goto exit;
+                return -ENODEV;
         }
 
         dev = usb_get_intfdata(interface);
-        if (!dev) {
-                retval = -ENODEV;
-                goto exit;
-        }
+        if (!dev)
+                return -ENODEV;
 
         /* increment our usage count for the device */
         kref_get(&dev->kref);
 
+        /* grab a power reference */
+        r = usb_autopm_get_interface(interface);
+        if (r < 0) {
+                kref_put(&dev->kref, lcd_delete);
+                return r;
+        }
+
         /* save our object in the file's private structure */
         file->private_data = dev;
 
-exit:
-        mutex_unlock(&usb_lcd_open_mutex);
-        return retval;
+        return 0;
 }
 
 static int lcd_release(struct inode *inode, struct file *file)
@@ -108,6 +108,7 @@ static int lcd_release(struct inode *inode, struct file *file)
                 return -ENODEV;
 
         /* decrement the count on our device */
+        usb_autopm_put_interface(dev->interface);
         kref_put(&dev->kref, lcd_delete);
         return 0;
 }
@@ -233,12 +234,14 @@ static ssize_t lcd_write(struct file *file, const char __user * user_buffer, siz
                           usb_sndbulkpipe(dev->udev, dev->bulk_out_endpointAddr),
                           buf, count, lcd_write_bulk_callback, dev);
         urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
+
+        usb_anchor_urb(urb, &dev->submitted);
         
         /* send the data out the bulk port */
         retval = usb_submit_urb(urb, GFP_KERNEL);
         if (retval) {
                 err("USBLCD: %s - failed submitting write urb, error %d", __FUNCTION__, retval);
-                goto error;
+                goto error_unanchor;
         }
         
         /* release our reference to this urb, the USB core will eventually free it entirely */
@@ -246,7 +249,8 @@ static ssize_t lcd_write(struct file *file, const char __user * user_buffer, siz
 
 exit:
         return count;
-
+error_unanchor:
+        usb_unanchor_urb(urb);
 error:
         usb_buffer_free(dev->udev, count, buf, urb->transfer_dma);
         usb_free_urb(urb);
@@ -291,6 +295,7 @@ static int lcd_probe(struct usb_interface *interface, const struct usb_device_id
         }
         kref_init(&dev->kref);
         sema_init(&dev->limit_sem, USB_LCD_CONCURRENT_WRITES);
+        init_usb_anchor(&dev->submitted);
 
         dev->udev = usb_get_dev(interface_to_usbdev(interface));
         dev->interface = interface;
@@ -358,22 +363,41 @@ error:
         return retval;
 }
 
+static void lcd_draw_down(struct usb_lcd *dev)
+{
+        int time;
+
+        time = usb_wait_anchor_empty_timeout(&dev->submitted, 1000);
+        if (!time)
+                usb_kill_anchored_urbs(&dev->submitted);
+}
+
+static int lcd_suspend(struct usb_interface *intf, pm_message_t message)
+{
+        struct usb_lcd *dev = usb_get_intfdata(intf);
+
+        if (!dev)
+                return 0;
+        lcd_draw_down(dev);
+        return 0;
+}
+
+static int lcd_resume (struct usb_interface *intf)
+{
+        return 0;
+}
+
 static void lcd_disconnect(struct usb_interface *interface)
 {
         struct usb_lcd *dev;
         int minor = interface->minor;
 
-        /* prevent skel_open() from racing skel_disconnect() */
-        mutex_lock(&usb_lcd_open_mutex);
-
         dev = usb_get_intfdata(interface);
         usb_set_intfdata(interface, NULL);
 
         /* give back our minor */
         usb_deregister_dev(interface, &lcd_class);
  
-        mutex_unlock(&usb_lcd_open_mutex);
-
         /* decrement our usage count */
         kref_put(&dev->kref, lcd_delete);
 
@@ -384,7 +408,10 @@ static struct usb_driver lcd_driver = {
         .name =         "usblcd",
         .probe =        lcd_probe,
         .disconnect =   lcd_disconnect,
+        .suspend =      lcd_suspend,
+        .resume =       lcd_resume,
         .id_table =     id_table,
+        .supports_autosuspend = 1,
 };
 
 static int __init usb_lcd_init(void)