[PATCH 3.4 130/177] USB: core: add device-qualifier quirk

From: lizf
Date: Tue Jan 27 2015 - 23:24:35 EST


From: Johan Hovold <johan@xxxxxxxxxx>

3.4.106-rc1 review patch. If anyone has any objections, please let me know.

------------------


commit 2a159389bf5d962359349a76827b2f683276a1c7 upstream.

Add new quirk for devices that cannot handle requests for the
device_qualifier descriptor.

A USB-2.0 compliant device must respond to requests for the
device_qualifier descriptor (even if it's with a request error), but at
least one device is known to misbehave after such a request.

Suggested-by: BjÃrn Mork <bjorn@xxxxxxx>
Signed-off-by: Johan Hovold <johan@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Zefan Li <lizefan@xxxxxxxxxx>
---
drivers/usb/core/hub.c | 3 +++
include/linux/usb/quirks.h | 3 +++
2 files changed, 6 insertions(+)

diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c
index 2d5177a..93f2538 100644
--- a/drivers/usb/core/hub.c
+++ b/drivers/usb/core/hub.c
@@ -3361,6 +3361,9 @@ check_highspeed (struct usb_hub *hub, struct usb_device *udev, int port1)
struct usb_qualifier_descriptor *qual;
int status;

+ if (udev->quirks & USB_QUIRK_DEVICE_QUALIFIER)
+ return;
+
qual = kmalloc (sizeof *qual, GFP_KERNEL);
if (qual == NULL)
return;
diff --git a/include/linux/usb/quirks.h b/include/linux/usb/quirks.h
index 8eeeb87..d0d2af0 100644
--- a/include/linux/usb/quirks.h
+++ b/include/linux/usb/quirks.h
@@ -33,4 +33,7 @@
/* device generates spurious wakeup, ignore remote wakeup capability */
#define USB_QUIRK_IGNORE_REMOTE_WAKEUP 0x00000200

+/* device can't handle device_qualifier descriptor requests */
+#define USB_QUIRK_DEVICE_QUALIFIER 0x00000100
+
#endif /* __LINUX_USB_QUIRKS_H */
--
1.9.1

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