Commit 19bc535e authored Jan 22, 2019 by Tejas Joglekar Committed by Greg Kroah-Hartman Feb 12, 2019

usb: dwc3: gadget: Handle 0 xfer length for OUT EP



commit 1e19cdc8060227b0802bda6bc0bd22b23679ba32 upstream.

For OUT endpoints, zero-length transfers require MaxPacketSize buffer as
per the DWC_usb3 programming guide 3.30a section 4.2.3.3.

This patch fixes this by explicitly checking zero length
transfer to correctly pad up to MaxPacketSize.

Fixes: c6267a51 ("usb: dwc3: gadget: align transfers to wMaxPacketSize")
Cc: stable@vger.kernel.org

Signed-off-by: Tejas Joglekar <joglekar@synopsys.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

parent a8438c38

drivers/usb/dwc3/gadget.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -1110,7 +1110,7 @@ static void dwc3_prepare_one_trb_linear(struct dwc3_ep *dep,
		unsigned int maxp = usb_endpoint_maxp(dep->endpoint.desc);
		unsigned int rem = length % maxp;

		if (rem && usb_endpoint_dir_out(dep->endpoint.desc)) {
		if ((!length \|\| rem) && usb_endpoint_dir_out(dep->endpoint.desc)) {
		struct dwc3 *dwc = dep->dwc;
		struct dwc3_trb *trb;