From: Thinh Nguyen <Thinh.Nguyen@synopsys.com>
Date: Tue, 30 Nov 2021 02:53:09 +0000 (-0800)
Subject: usb: dwc3: gadget: Skip checking Update Transfer status
X-Git-Tag: block-5.17-2022-01-21~30^2~77
X-Git-Url: https://git.kernel.dk/?a=commitdiff_plain;h=bc27117c7cdd4b57d0f079620b483f3b229074bd;p=linux-block.git

usb: dwc3: gadget: Skip checking Update Transfer status

If we're not setting CMDACT (from "No Response" Update Transfer
command), then there's no point in checking for the command status. So
skip it. This can reduce a register read delay and improve performance.

Signed-off-by: Thinh Nguyen <Thinh.Nguyen@synopsys.com>
Link: https://lore.kernel.org/r/3dc31cf11581ae3ee82d9202dda3fc17d897d786.1638240306.git.Thinh.Nguyen@synopsys.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
index 7e3db00e9759..00b3f19c4d3e 100644
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -357,6 +357,12 @@ int dwc3_send_gadget_ep_cmd(struct dwc3_ep *dep, unsigned int cmd,
 		cmd |= DWC3_DEPCMD_CMDACT;
 
 	dwc3_writel(dep->regs, DWC3_DEPCMD, cmd);
+
+	if (!(cmd & DWC3_DEPCMD_CMDACT)) {
+		ret = 0;
+		goto skip_status;
+	}
+
 	do {
 		reg = dwc3_readl(dep->regs, DWC3_DEPCMD);
 		if (!(reg & DWC3_DEPCMD_CMDACT)) {
@@ -398,6 +404,7 @@ int dwc3_send_gadget_ep_cmd(struct dwc3_ep *dep, unsigned int cmd,
 		cmd_status = -ETIMEDOUT;
 	}
 
+skip_status:
 	trace_dwc3_gadget_ep_cmd(dep, cmd, params, cmd_status);
 
 	if (DWC3_DEPCMD_CMD(cmd) == DWC3_DEPCMD_STARTTRANSFER) {