From: Pawel Laszczak pawell@cadence.com
[ Upstream commit 26adde04acdff14a1f28d4a5dce46a8513a3038b ]
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: Peter Chen peter.chen@kernel.org Reviewed-by: Laurent Pinchart laurent.pinchart@ideasonboard.com Signed-off-by: Pawel Laszczak pawell@cadence.com Link: https://lore.kernel.org/r/20210308125338.4824-1-pawell@gli-login.cadence.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/usb/gadget/function/f_uvc.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-)
diff --git a/drivers/usb/gadget/function/f_uvc.c b/drivers/usb/gadget/function/f_uvc.c index fb0a892687c0..79ecdbb936c1 100644 --- a/drivers/usb/gadget/function/f_uvc.c +++ b/drivers/usb/gadget/function/f_uvc.c @@ -633,7 +633,12 @@ 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)); - uvc_hs_streaming_ep.bInterval = opts->streaming_interval; + + /* 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); uvc_ss_streaming_ep.bInterval = opts->streaming_interval;