Commit 26adde04 authored by Pawel Laszczak's avatar Pawel Laszczak Committed by Greg Kroah-Hartman
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usb: gadget: uvc: add bInterval checking for HS mode 



Patch adds extra checking for bInterval passed by configfs.
The 5.6.4 chapter of USB Specification (rev. 2.0) say:
"A high-bandwidth endpoint must specify a period of 1x125 µs
(i.e., a bInterval value of 1)."

The issue was observed during testing UVC class on CV.
I treat this change as improvement because we can control
bInterval by configfs.

Reviewed-by: default avatarPeter Chen <peter.chen@kernel.org>
Reviewed-by: default avatarLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: default avatarPawel Laszczak <pawell@cadence.com>
Link: https://lore.kernel.org/r/20210308125338.4824-1-pawell@gli-login.cadence.com


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 064ece8d

drivers/usb/gadget/function/f_uvc.c

+6 −1
Original line number Diff line number Diff line
@@ -633,6 +633,11 @@ uvc_function_bind(struct usb_configuration *c, struct usb_function *f) 


	uvc_hs_streaming_ep.wMaxPacketSize =

		cpu_to_le16(max_packet_size | ((max_packet_mult - 1) << 11));



	/* A high-bandwidth endpoint must specify a bInterval value of 1 */

	if (max_packet_mult > 1)

		uvc_hs_streaming_ep.bInterval = 1;

	else

		uvc_hs_streaming_ep.bInterval = opts->streaming_interval;



	uvc_ss_streaming_ep.wMaxPacketSize = cpu_to_le16(max_packet_size);