From 16bb05d98c904a4f6c5ce7e2d992299f794acbf2 Mon Sep 17 00:00:00 2001 From: Roger Quadros Date: Wed, 8 Mar 2017 16:05:44 +0200 Subject: [PATCH] usb: gadget: f_uvc: Sanity check wMaxPacketSize for SuperSpeed As per USB3.0 Specification "Table 9-20. Standard Endpoint Descriptor", for interrupt and isochronous endpoints, wMaxPacketSize must be set to 1024 if the endpoint defines bMaxBurst to be greater than zero. Reviewed-by: Laurent Pinchart Signed-off-by: Roger Quadros Signed-off-by: Felipe Balbi --- drivers/usb/gadget/function/f_uvc.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/drivers/usb/gadget/function/f_uvc.c b/drivers/usb/gadget/function/f_uvc.c index c7689d0..f8a1881 100644 --- a/drivers/usb/gadget/function/f_uvc.c +++ b/drivers/usb/gadget/function/f_uvc.c @@ -594,6 +594,14 @@ uvc_function_bind(struct usb_configuration *c, struct usb_function *f) opts->streaming_maxpacket = clamp(opts->streaming_maxpacket, 1U, 3072U); opts->streaming_maxburst = min(opts->streaming_maxburst, 15U); + /* For SS, wMaxPacketSize has to be 1024 if bMaxBurst is not 0 */ + if (opts->streaming_maxburst && + (opts->streaming_maxpacket % 1024) != 0) { + opts->streaming_maxpacket = roundup(opts->streaming_maxpacket, 1024); + INFO(cdev, "overriding streaming_maxpacket to %d\n", + opts->streaming_maxpacket); + } + /* Fill in the FS/HS/SS Video Streaming specific descriptors from the * module parameters. * -- 2.7.4