Merge branch 'timers-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel...

[pandora-kernel.git] / drivers / usb / core / message.c

diff --git a/drivers/usb/core/message.c b/drivers/usb/core/message.c
index 2bed83c..9720e69 100644 (file)
--- a/drivers/usb/core/message.c
+++ b/drivers/usb/core/message.c
@@ -806,6 +806,48 @@ static int usb_string_sub(struct usb_device *dev, unsigned int langid,
        return rc;
 }
 
+static int usb_get_langid(struct usb_device *dev, unsigned char *tbuf)
+{
+       int err;
+
+       if (dev->have_langid)
+               return 0;
+
+       if (dev->string_langid < 0)
+               return -EPIPE;
+
+       err = usb_string_sub(dev, 0, 0, tbuf);
+
+       /* If the string was reported but is malformed, default to english
+        * (0x0409) */
+       if (err == -ENODATA || (err > 0 && err < 4)) {
+               dev->string_langid = 0x0409;
+               dev->have_langid = 1;
+               dev_err(&dev->dev,
+                       "string descriptor 0 malformed (err = %d), "
+                       "defaulting to 0x%04x\n",
+                               err, dev->string_langid);
+               return 0;
+       }
+
+       /* In case of all other errors, we assume the device is not able to
+        * deal with strings at all. Set string_langid to -1 in order to
+        * prevent any string to be retrieved from the device */
+       if (err < 0) {
+               dev_err(&dev->dev, "string descriptor 0 read error: %d\n",
+                                       err);
+               dev->string_langid = -1;
+               return -EPIPE;
+       }
+
+       /* always use the first langid listed */
+       dev->string_langid = tbuf[2] | (tbuf[3] << 8);
+       dev->have_langid = 1;
+       dev_dbg(&dev->dev, "default language 0x%04x\n",
+                               dev->string_langid);
+       return 0;
+}
+
 /**
  * usb_string - returns UTF-8 version of a string descriptor
  * @dev: the device whose string descriptor is being retrieved
@@ -837,24 +879,9 @@ int usb_string(struct usb_device *dev, int index, char *buf, size_t size)
        if (!tbuf)
                return -ENOMEM;
 
-       /* get langid for strings if it's not yet known */
-       if (!dev->have_langid) {
-               err = usb_string_sub(dev, 0, 0, tbuf);
-               if (err < 0) {
-                       dev_err(&dev->dev,
-                               "string descriptor 0 read error: %d\n",
-                               err);
-               } else if (err < 4) {
-                       dev_err(&dev->dev, "string descriptor 0 too short\n");
-               } else {
-                       dev->string_langid = tbuf[2] | (tbuf[3] << 8);
-                       /* always use the first langid listed */
-                       dev_dbg(&dev->dev, "default language 0x%04x\n",
-                               dev->string_langid);
-               }
-
-               dev->have_langid = 1;
-       }
+       err = usb_get_langid(dev, tbuf);
+       if (err < 0)
+               goto errout;
 
        err = usb_string_sub(dev, dev->string_langid, index, tbuf);
        if (err < 0)