[PATCH] drivers: usb: host: Fix the write to W1C fields in HPRT register

[teik.heng.chong at intel.com]

From: Teik Heng Chong <teik.heng.chong at intel.com>

Fix the write to the HPRT register which treat W1C fields
as if they were mere RW. This leads to unintended clearing of such fields

Signed-off-by: Teik Heng Chong <teik.heng.chong at intel.com>
---
 drivers/usb/host/dwc2.c | 34 ++++++++--------------------------
 drivers/usb/host/dwc2.h |  4 ++++
 2 files changed, 12 insertions(+), 26 deletions(-)

diff --git a/drivers/usb/host/dwc2.c b/drivers/usb/host/dwc2.c
index 23060fc369..9818f9be94 100644
--- a/drivers/usb/host/dwc2.c
+++ b/drivers/usb/host/dwc2.c
@@ -315,9 +315,7 @@ static void dwc_otg_core_host_init(struct udevice *dev,
 
 	/* Turn on the vbus power. */
 	if (readl(&regs->gintsts) & DWC2_GINTSTS_CURMODE_HOST) {
-		hprt0 = readl(&regs->hprt0);
-		hprt0 &= ~(DWC2_HPRT0_PRTENA | DWC2_HPRT0_PRTCONNDET);
-		hprt0 &= ~(DWC2_HPRT0_PRTENCHNG | DWC2_HPRT0_PRTOVRCURRCHNG);
+		hprt0 = readl(&regs->hprt0) & ~DWC2_HPRT0_W1C_MASK;
 		if (!(hprt0 & DWC2_HPRT0_PRTPWR)) {
 			hprt0 |= DWC2_HPRT0_PRTPWR;
 			writel(hprt0, &regs->hprt0);
@@ -748,7 +746,7 @@ static int dwc_otg_submit_rh_msg_out(struct dwc2_priv *priv,
 	case (USB_REQ_CLEAR_FEATURE << 8) | USB_RECIP_OTHER | USB_TYPE_CLASS:
 		switch (wValue) {
 		case USB_PORT_FEAT_C_CONNECTION:
-			setbits_le32(&regs->hprt0, DWC2_HPRT0_PRTCONNDET);
+			clrsetbits_le32(&regs->hprt0, DWC2_HPRT0_W1C_MASK, DWC2_HPRT0_PRTCONNDET);
 			break;
 		}
 		break;
@@ -759,21 +757,13 @@ static int dwc_otg_submit_rh_msg_out(struct dwc2_priv *priv,
 			break;
 
 		case USB_PORT_FEAT_RESET:
-			clrsetbits_le32(&regs->hprt0, DWC2_HPRT0_PRTENA |
-					DWC2_HPRT0_PRTCONNDET |
-					DWC2_HPRT0_PRTENCHNG |
-					DWC2_HPRT0_PRTOVRCURRCHNG,
-					DWC2_HPRT0_PRTRST);
+			clrsetbits_le32(&regs->hprt0, DWC2_HPRT0_W1C_MASK, DWC2_HPRT0_PRTRST);
 			mdelay(50);
-			clrbits_le32(&regs->hprt0, DWC2_HPRT0_PRTRST);
+			clrbits_le32(&regs->hprt0, DWC2_HPRT0_W1C_MASK | DWC2_HPRT0_PRTRST);
 			break;
 
 		case USB_PORT_FEAT_POWER:
-			clrsetbits_le32(&regs->hprt0, DWC2_HPRT0_PRTENA |
-					DWC2_HPRT0_PRTCONNDET |
-					DWC2_HPRT0_PRTENCHNG |
-					DWC2_HPRT0_PRTOVRCURRCHNG,
-					DWC2_HPRT0_PRTRST);
+			clrsetbits_le32(&regs->hprt0, DWC2_HPRT0_W1C_MASK, DWC2_HPRT0_PRTRST);
 			break;
 
 		case USB_PORT_FEAT_ENABLE:
@@ -1213,14 +1203,9 @@ static int dwc2_init_common(struct udevice *dev, struct dwc2_priv *priv)
 		dwc_otg_core_host_init(dev, regs);
 	}
 
-	clrsetbits_le32(&regs->hprt0, DWC2_HPRT0_PRTENA |
-			DWC2_HPRT0_PRTCONNDET | DWC2_HPRT0_PRTENCHNG |
-			DWC2_HPRT0_PRTOVRCURRCHNG,
-			DWC2_HPRT0_PRTRST);
+	clrsetbits_le32(&regs->hprt0, DWC2_HPRT0_W1C_MASK, DWC2_HPRT0_PRTRST);
 	mdelay(50);
-	clrbits_le32(&regs->hprt0, DWC2_HPRT0_PRTENA | DWC2_HPRT0_PRTCONNDET |
-		     DWC2_HPRT0_PRTENCHNG | DWC2_HPRT0_PRTOVRCURRCHNG |
-		     DWC2_HPRT0_PRTRST);
+	clrbits_le32(&regs->hprt0, DWC2_HPRT0_W1C_MASK | DWC2_HPRT0_PRTRST);
 
 	for (i = 0; i < MAX_DEVICE; i++) {
 		for (j = 0; j < MAX_ENDPOINT; j++) {
@@ -1246,10 +1231,7 @@ static int dwc2_init_common(struct udevice *dev, struct dwc2_priv *priv)
 static void dwc2_uninit_common(struct dwc2_core_regs *regs)
 {
 	/* Put everything in reset. */
-	clrsetbits_le32(&regs->hprt0, DWC2_HPRT0_PRTENA |
-			DWC2_HPRT0_PRTCONNDET | DWC2_HPRT0_PRTENCHNG |
-			DWC2_HPRT0_PRTOVRCURRCHNG,
-			DWC2_HPRT0_PRTRST);
+	clrsetbits_le32(&regs->hprt0, DWC2_HPRT0_W1C_MASK, DWC2_HPRT0_PRTRST);
 }
 
 #if !CONFIG_IS_ENABLED(DM_USB)
diff --git a/drivers/usb/host/dwc2.h b/drivers/usb/host/dwc2.h
index a6f562fe60..6f022e33a1 100644
--- a/drivers/usb/host/dwc2.h
+++ b/drivers/usb/host/dwc2.h
@@ -543,6 +543,10 @@ struct dwc2_core_regs {
 #define DWC2_HPRT0_PRTSPD_LOW				(2 << 17)
 #define DWC2_HPRT0_PRTSPD_MASK				(0x3 << 17)
 #define DWC2_HPRT0_PRTSPD_OFFSET			17
+#define DWC2_HPRT0_W1C_MASK				(DWC2_HPRT0_PRTCONNDET | \
+							DWC2_HPRT0_PRTENA | \
+							DWC2_HPRT0_PRTENCHNG | \
+							DWC2_HPRT0_PRTOVRCURRCHNG)
 #define DWC2_HAINT_CH0					(1 << 0)
 #define DWC2_HAINT_CH0_OFFSET				0
 #define DWC2_HAINT_CH1					(1 << 1)
-- 
2.25.1