USB: add a blacklist for devices that can't handle some things we throw at them.

This adds a blacklist to the USB core to handle some autosuspend and
string issues that devices have.

Originally written by Oliver, but hacked up a lot by Greg.

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

1 files changed, 5 insertions, 1 deletions

diff --git a/drivers/usb/core/message.c b/drivers/usb/core/message.c
index 74edaea5665d..2f17468b5c1e 100644
--- a/drivers/usb/core/message.c
+++ b/drivers/usb/core/message.c
@@ -11,6 +11,7 @@
 #include <linux/timer.h>
 #include <linux/ctype.h>
 #include <linux/device.h>
+#include <linux/usb/quirks.h>
 #include <asm/byteorder.h>
 #include <asm/scatterlist.h>
 
@@ -685,7 +686,10 @@ static int usb_string_sub(struct usb_device *dev, unsigned int langid,
 
         /* Try to read the string descriptor by asking for the maximum
          * possible number of bytes */
-        rc = usb_get_string(dev, langid, index, buf, 255);
+        if (dev->quirks & USB_QUIRK_STRING_FETCH_255)
+                rc = -EIO;
+        else
+                rc = usb_get_string(dev, langid, index, buf, 255);
 
         /* If that failed try to read the descriptor length, then
          * ask for just that many bytes */