Hi,
We're using the HID gadget driver as the basis for a multi-touch gadget
driver. When connected to a VIA VL800 (3.0) USB controller, Windows 7 says:
"Hardware Id Missing. Windows cannot identify the device plugged into
the VIA USB 2 Hub".
The following patch fixes that problem (and works fine with other USB
controller drivers, at least Renesas and Intel).
http://www.usb.org/developers/devclass_docs/HID1_11.pdf is quite
specific about the HID device class:
"The bDeviceClass and bDeviceSubClass fields in the Device Descriptor
should not be used to identify a device as belonging to the HID class.
Instead use the bInterfaceClass and bInterfaceSubClass fields in the
Interface descriptor."
I couldn't find the original rationale for setting the device class to
"misc" (0xEF).
diff --git a/drivers/usb/gadget/hid.c b/drivers/usb/gadget/hid.c
index f888c3e..3493adf 100644
--- a/drivers/usb/gadget/hid.c
+++ b/drivers/usb/gadget/hid.c
@@ -60,9 +60,9 @@ static struct usb_device_descriptor device_desc = {
/* .bDeviceClass = USB_CLASS_COMM, */
/* .bDeviceSubClass = 0, */
/* .bDeviceProtocol = 0, */
- .bDeviceClass = 0xEF,
- .bDeviceSubClass = 2,
- .bDeviceProtocol = 1,
+ .bDeviceClass = USB_CLASS_PER_INTERFACE,
+ .bDeviceSubClass = 0,
+ .bDeviceProtocol = 0,
/* .bMaxPacketSize0 = f(hardware) */
--
Orjan Friberg
FlatFrog Laboratories AB
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