usb: gadget: hid: don't STALL when processing a HID Descriptor request

This is a patch to fix an issue with the HID gadget which, at the moment,
returns STALL on a HID descriptor request. Essentially, the patch changes
the hid gadget such that a request for the HID descriptor is handled by
copying the descriptor into the response buffer, rather than falling
through the default case, in which the request is answered by a STALL.

Signed-off-by: Sebastian Bauer <mail@sebastianbauer.info>
Acked-by: Peter Korsgaard <peter.korsgaard@barco.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

diff --git a/drivers/usb/gadget/f_hid.c b/drivers/usb/gadget/f_hid.c
index 403a48b..83a266b 100644 (file)
--- a/drivers/usb/gadget/f_hid.c
+++ b/drivers/usb/gadget/f_hid.c
@@ -367,6 +367,13 @@ static int hidg_setup(struct usb_function *f,
        case ((USB_DIR_IN | USB_TYPE_STANDARD | USB_RECIP_INTERFACE) << 8
                  | USB_REQ_GET_DESCRIPTOR):
                switch (value >> 8) {
+               case HID_DT_HID:
+                       VDBG(cdev, "USB_REQ_GET_DESCRIPTOR: HID\n");
+                       length = min_t(unsigned short, length,
+                                                  hidg_desc.bLength);
+                       memcpy(req->buf, &hidg_desc, length);
+                       goto respond;
+                       break;
                case HID_DT_REPORT:
                        VDBG(cdev, "USB_REQ_GET_DESCRIPTOR: REPORT\n");
                        length = min_t(unsigned short, length,