[U-Boot] [PATCH] drivers: usb: xhci-fsl: Implement Erratum A-010151 for FSL USB3 controller

[Sriram Dash]

Currently the controller by default enables the Receive Detect feature in P3
mode in USB 3.0 PHY. However, USB 3.0 PHY does not reliably support receive
detection in P3 mode.
Enabling the USB3 controller to configure USB in P2 mode whenever the Receive
Detect feature is required.

Signed-off-by: Sriram Dash <sriram.dash at nxp.com>
Signed-off-by: Rajesh Bhagat <rajesh.bhagat at nxp.com>
---
 drivers/usb/host/xhci-dwc3.c | 5 +++++
 drivers/usb/host/xhci-fsl.c  | 7 +++++++
 include/linux/usb/dwc3.h     | 2 ++
 3 files changed, 14 insertions(+)

diff --git a/drivers/usb/host/xhci-dwc3.c b/drivers/usb/host/xhci-dwc3.c
index 33961cd..adbd9b5 100644
--- a/drivers/usb/host/xhci-dwc3.c
+++ b/drivers/usb/host/xhci-dwc3.c
@@ -97,3 +97,8 @@ void dwc3_set_fladj(struct dwc3 *dwc3_reg, u32 val)
 	setbits_le32(&dwc3_reg->g_fladj, GFLADJ_30MHZ_REG_SEL |
 			GFLADJ_30MHZ(val));
 }
+
+void dwc3_set_rxdetect_power_mode(struct dwc3 *dwc3_reg, u32 val)
+{
+	setbits_le32(&dwc3_reg->g_usb3pipectl[0], val);
+}
diff --git a/drivers/usb/host/xhci-fsl.c b/drivers/usb/host/xhci-fsl.c
index bdcd4f1..d9dbf1f 100644
--- a/drivers/usb/host/xhci-fsl.c
+++ b/drivers/usb/host/xhci-fsl.c
@@ -74,6 +74,13 @@ static int fsl_xhci_core_init(struct fsl_xhci *fsl_xhci)
 	/* Set GFLADJ_30MHZ as 20h as per XHCI spec default value */
 	dwc3_set_fladj(fsl_xhci->dwc3_reg, GFLADJ_30MHZ_DEFAULT);
 
+	/*
+	 * A-010151: USB controller to configure USB in P2 mode
+	 * whenever the Receive Detect feature is required
+	 */
+	dwc3_set_rxdetect_power_mode(fsl_xhci->dwc3_reg,
+				     DWC3_GUSB3PIPECTL_DISRXDETP3);
+
 	return ret;
 }
 
diff --git a/include/linux/usb/dwc3.h b/include/linux/usb/dwc3.h
index 6d1e365..f68cdd2 100644
--- a/include/linux/usb/dwc3.h
+++ b/include/linux/usb/dwc3.h
@@ -184,6 +184,7 @@ struct dwc3 {					/* offset: 0xC100 */
 
 /* Global USB3 PIPE Control Register */
 #define DWC3_GUSB3PIPECTL_PHYSOFTRST		(1 << 31)
+#define DWC3_GUSB3PIPECTL_DISRXDETP3		(1 << 28)
 #define DWC3_GUSB3PIPECTL_SUSPHY		(1 << 17)
 
 /* Global TX Fifo Size Register */
@@ -205,5 +206,6 @@ void dwc3_set_mode(struct dwc3 *dwc3_reg, u32 mode);
 void dwc3_core_soft_reset(struct dwc3 *dwc3_reg);
 int dwc3_core_init(struct dwc3 *dwc3_reg);
 void dwc3_set_fladj(struct dwc3 *dwc3_reg, u32 val);
+void dwc3_set_rxdetect_power_mode(struct dwc3 *dwc3_reg, u32 val);
 #endif
 #endif /* __DWC3_H_ */
-- 
2.1.0