From: Razmik Karapetyan <razmik@synopsys.com>
Date: Wed, 16 Nov 2016 23:33:55 +0000 (-0800)
Subject: usb: dwc2: Don't program DMA address for 0 length request
X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=729e65746d4f225792e33371f3ae6d614ec66032;p=GitHub%2FLineageOS%2Fandroid_kernel_motorola_exynos9610.git

usb: dwc2: Don't program DMA address for 0 length request

Check the request length in dwc2_hsotg_start_req() function. If
length == 0, do not write DMA address to control register.

Signed-off-by: Razmik Karapetyan <razmik@synopsys.com>
Signed-off-by: John Youn <johnyoun@synopsys.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
---

diff --git a/drivers/usb/dwc2/gadget.c b/drivers/usb/dwc2/gadget.c
index ad0cd0e38f06..4dd5f1e2d281 100644
--- a/drivers/usb/dwc2/gadget.c
+++ b/drivers/usb/dwc2/gadget.c
@@ -1018,7 +1018,7 @@ static void dwc2_hsotg_start_req(struct dwc2_hsotg *hsotg,
 		/* write size / packets */
 		dwc2_writel(epsize, hsotg->regs + epsize_reg);
 
-		if (using_dma(hsotg) && !continuing) {
+		if (using_dma(hsotg) && !continuing && (length != 0)) {
 			/*
 			 * write DMA address to control register, buffer
 			 * already synced by dwc2_hsotg_ep_queue().