[PATCH 0/2] usb: dwc3: Valid HW capability

[PATCH 0/2] usb: dwc3: Valid HW capability

[Thinh Nguyen]

The field dwc->maximum_speed captures the device "maximum-speed" property. If
the property is not set, then default the field to the maximum speed the HW
supports.

This series makes sure that the user input takes precedence and only prints
warning if the user specifies a maximum-speed higher than what the HW shows.


Thinh Nguyen (2):
  usb: dwc3: core: Properly default unspecified speed
  usb: dwc3: core: Print warning on unsupported speed

 drivers/usb/dwc3/core.c | 44 +++++++++++++++++++++++++++-----------------
 1 file changed, 27 insertions(+), 17 deletions(-)


base-commit: a95fcda246dc3e9f5d00222c9a8f0a76aa0bb950
-- 
2.11.0

[PATCH 1/2] usb: dwc3: core: Properly default unspecified speed

[Thinh Nguyen]

If the maximum_speed is not specified, default the device speed base on
its HW capability. Don't prematurely check HW capability before
validating the maximum_speed device property. The device property takes
precedence in dwc->maximum_speed.

Fixes: 0e1e5c47f7a9 ("usb: dwc3: add support for USB 2.0-only core configuration")
Reported-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
Signed-off-by: Thinh Nguyen <thinhn@synopsys.com>
---
 drivers/usb/dwc3/core.c | 35 ++++++++++++++++++-----------------
 1 file changed, 18 insertions(+), 17 deletions(-)

diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
index 422aea24afcd..7f6f5567b118 100644
--- a/drivers/usb/dwc3/core.c
+++ b/drivers/usb/dwc3/core.c
@@ -930,13 +930,6 @@ static int dwc3_core_init(struct dwc3 *dwc)
 	 */
 	dwc3_writel(dwc->regs, DWC3_GUID, LINUX_VERSION_CODE);
 
-	/* Handle USB2.0-only core configuration */
-	if (DWC3_GHWPARAMS3_SSPHY_IFC(dwc->hwparams.hwparams3) ==
-			DWC3_GHWPARAMS3_SSPHY_IFC_DIS) {
-		if (dwc->maximum_speed == USB_SPEED_SUPER)
-			dwc->maximum_speed = USB_SPEED_HIGH;
-	}
-
 	ret = dwc3_phy_setup(dwc);
 	if (ret)
 		goto err0;
@@ -1382,6 +1375,8 @@ bool dwc3_has_imod(struct dwc3 *dwc)
 static void dwc3_check_params(struct dwc3 *dwc)
 {
 	struct device *dev = dwc->dev;
+	unsigned int hwparam_gen =
+		DWC3_GHWPARAMS3_SSPHY_IFC(dwc->hwparams.hwparams3);
 
 	/* Check for proper value of imod_interval */
 	if (dwc->imod_interval && !dwc3_has_imod(dwc)) {
@@ -1413,17 +1408,23 @@ static void dwc3_check_params(struct dwc3 *dwc)
 			dwc->maximum_speed);
 		/* fall through */
 	case USB_SPEED_UNKNOWN:
-		/* default to superspeed */
-		dwc->maximum_speed = USB_SPEED_SUPER;
-
-		/*
-		 * default to superspeed plus if we are capable.
-		 */
-		if ((DWC3_IP_IS(DWC31) || DWC3_IP_IS(DWC32)) &&
-		    (DWC3_GHWPARAMS3_SSPHY_IFC(dwc->hwparams.hwparams3) ==
-		     DWC3_GHWPARAMS3_SSPHY_IFC_GEN2))
+		switch (hwparam_gen) {
+		case DWC3_GHWPARAMS3_SSPHY_IFC_GEN2:
 			dwc->maximum_speed = USB_SPEED_SUPER_PLUS;
-
+			break;
+		case DWC3_GHWPARAMS3_SSPHY_IFC_GEN1:
+			if (DWC3_IP_IS(DWC32))
+				dwc->maximum_speed = USB_SPEED_SUPER_PLUS;
+			else
+				dwc->maximum_speed = USB_SPEED_SUPER;
+			break;
+		case DWC3_GHWPARAMS3_SSPHY_IFC_DIS:
+			dwc->maximum_speed = USB_SPEED_HIGH;
+			break;
+		default:
+			dwc->maximum_speed = USB_SPEED_SUPER;
+			break;
+		}
 		break;
 	}
 }
-- 
2.11.0

[PATCH 2/2] usb: dwc3: core: Print warning on unsupported speed

[Thinh Nguyen]

The user may have more information to override the HW parameter to
specify the maximum_speed. However, if the user specifies a
maximum_speed that the controller doesn't support, print out a warning.

Signed-off-by: Thinh Nguyen <thinhn@synopsys.com>
---
 drivers/usb/dwc3/core.c | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
index 7f6f5567b118..b2ea96d2db04 100644
--- a/drivers/usb/dwc3/core.c
+++ b/drivers/usb/dwc3/core.c
@@ -1400,8 +1400,17 @@ static void dwc3_check_params(struct dwc3 *dwc)
 	case USB_SPEED_LOW:
 	case USB_SPEED_FULL:
 	case USB_SPEED_HIGH:
+		break;
 	case USB_SPEED_SUPER:
+		if (hwparam_gen == DWC3_GHWPARAMS3_SSPHY_IFC_DIS)
+			dev_warn(dev, "UDC doesn't support Gen 1\n");
+		break;
 	case USB_SPEED_SUPER_PLUS:
+		if ((DWC3_IP_IS(DWC32) &&
+		     hwparam_gen == DWC3_GHWPARAMS3_SSPHY_IFC_DIS) ||
+		    (!DWC3_IP_IS(DWC32) &&
+		     hwparam_gen != DWC3_GHWPARAMS3_SSPHY_IFC_GEN2))
+			dev_warn(dev, "UDC doesn't support SSP\n");
 		break;
 	default:
 		dev_err(dev, "invalid maximum_speed parameter %d\n",
-- 
2.11.0