1 files changed, 22 insertions, 11 deletions

diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
index 7e3db00e9759..c0c89374716b 100644
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -331,9 +331,17 @@ int dwc3_send_gadget_ep_cmd(struct dwc3_ep *dep, unsigned int cmd,
 		}
 	}
 
-	dwc3_writel(dep->regs, DWC3_DEPCMDPAR0, params->param0);
-	dwc3_writel(dep->regs, DWC3_DEPCMDPAR1, params->param1);
-	dwc3_writel(dep->regs, DWC3_DEPCMDPAR2, params->param2);
+	/*
+	 * For some commands such as Update Transfer command, DEPCMDPARn
+	 * registers are reserved. Since the driver often sends Update Transfer
+	 * command, don't write to DEPCMDPARn to avoid register write delays and
+	 * improve performance.
+	 */
+	if (DWC3_DEPCMD_CMD(cmd) != DWC3_DEPCMD_UPDATETRANSFER) {
+		dwc3_writel(dep->regs, DWC3_DEPCMDPAR0, params->param0);
+		dwc3_writel(dep->regs, DWC3_DEPCMDPAR1, params->param1);
+		dwc3_writel(dep->regs, DWC3_DEPCMDPAR2, params->param2);
+	}
 
 	/*
 	 * Synopsys Databook 2.60a states in section 6.3.2.5.6 of that if we're
@@ -357,6 +365,12 @@ 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 +412,7 @@ 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) {
@@ -4067,7 +4082,6 @@ static irqreturn_t dwc3_process_event_buf(struct dwc3_event_buffer *evt)
 	struct dwc3 *dwc = evt->dwc;
 	irqreturn_t ret = IRQ_NONE;
 	int left;
-	u32 reg;
 
 	left = evt->count;
 
@@ -4099,9 +4113,8 @@ static irqreturn_t dwc3_process_event_buf(struct dwc3_event_buffer *evt)
 	ret = IRQ_HANDLED;
 
 	/* Unmask interrupt */
-	reg = dwc3_readl(dwc->regs, DWC3_GEVNTSIZ(0));
-	reg &= ~DWC3_GEVNTSIZ_INTMASK;
-	dwc3_writel(dwc->regs, DWC3_GEVNTSIZ(0), reg);
+	dwc3_writel(dwc->regs, DWC3_GEVNTSIZ(0),
+		    DWC3_GEVNTSIZ_SIZE(evt->length));
 
 	if (dwc->imod_interval) {
 		dwc3_writel(dwc->regs, DWC3_GEVNTCOUNT(0), DWC3_GEVNTCOUNT_EHB);
@@ -4130,7 +4143,6 @@ static irqreturn_t dwc3_check_event_buf(struct dwc3_event_buffer *evt)
 	struct dwc3 *dwc = evt->dwc;
 	u32 amount;
 	u32 count;
-	u32 reg;
 
 	if (pm_runtime_suspended(dwc->dev)) {
 		pm_runtime_get(dwc->dev);
@@ -4157,9 +4169,8 @@ static irqreturn_t dwc3_check_event_buf(struct dwc3_event_buffer *evt)
 	evt->flags |= DWC3_EVENT_PENDING;
 
 	/* Mask interrupt */
-	reg = dwc3_readl(dwc->regs, DWC3_GEVNTSIZ(0));
-	reg |= DWC3_GEVNTSIZ_INTMASK;
-	dwc3_writel(dwc->regs, DWC3_GEVNTSIZ(0), reg);
+	dwc3_writel(dwc->regs, DWC3_GEVNTSIZ(0),
+		    DWC3_GEVNTSIZ_INTMASK | DWC3_GEVNTSIZ_SIZE(evt->length));
 
 	amount = min(count, evt->length - evt->lpos);
 	memcpy(evt->cache + evt->lpos, evt->buf + evt->lpos, amount);