usb: dwc3: add ULPI interface support

Registers DWC3's ULPI interface with the ULPI bus when it's
available.

Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Acked-by: David Cohen <david.a.cohen@linux.intel.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

1 files changed, 31 insertions, 3 deletions

diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
index 0de8968a2e97..5c110d8e293b 100644
--- a/drivers/usb/dwc3/core.c
+++ b/drivers/usb/dwc3/core.c
@@ -394,10 +394,15 @@ static void dwc3_cache_hwparams(struct dwc3 *dwc)
 /**
  * dwc3_phy_setup - Configure USB PHY Interface of DWC3 Core
  * @dwc: Pointer to our controller context structure
+ *
+ * Returns 0 on success. The USB PHY interfaces are configured but not
+ * initialized. The PHY interfaces and the PHYs get initialized together with
+ * the core in dwc3_core_init.
  */
-static void dwc3_phy_setup(struct dwc3 *dwc)
+static int dwc3_phy_setup(struct dwc3 *dwc)
 {
 	u32 reg;
+	int ret;
 
 	reg = dwc3_readl(dwc->regs, DWC3_GUSB3PIPECTL(0));
 
@@ -443,13 +448,30 @@ static void dwc3_phy_setup(struct dwc3 *dwc)
 	case DWC3_GHWPARAMS3_HSPHY_IFC_UTMI_ULPI:
 		if (!strncmp(dwc->hsphy_interface, "utmi", 4)) {
 			reg &= ~DWC3_GUSB2PHYCFG_ULPI_UTMI;
+			break;
 		} else if (!strncmp(dwc->hsphy_interface, "ulpi", 4)) {
 			reg |= DWC3_GUSB2PHYCFG_ULPI_UTMI;
+			dwc3_writel(dwc->regs, DWC3_GUSB2PHYCFG(0), reg);
 		} else {
 			dev_warn(dwc->dev, "HSPHY Interface not defined\n");
-			break;
+
+			/* Relying on default value. */
+			if (!(reg & DWC3_GUSB2PHYCFG_ULPI_UTMI))
+				break;
 		}
 		/* FALLTHROUGH */
+	case DWC3_GHWPARAMS3_HSPHY_IFC_ULPI:
+		/* Making sure the interface and PHY are operational */
+		ret = dwc3_soft_reset(dwc);
+		if (ret)
+			return ret;
+
+		udelay(1);
+
+		ret = dwc3_ulpi_init(dwc);
+		if (ret)
+			return ret;
+		/* FALLTHROUGH */
 	default:
 		break;
 	}
@@ -467,6 +489,8 @@ static void dwc3_phy_setup(struct dwc3 *dwc)
 		reg &= ~DWC3_GUSB2PHYCFG_SUSPHY;
 
 	dwc3_writel(dwc->regs, DWC3_GUSB2PHYCFG(0), reg);
+
+	return 0;
 }
 
 /**
@@ -906,7 +930,9 @@ static int dwc3_probe(struct platform_device *pdev)
 	platform_set_drvdata(pdev, dwc);
 	dwc3_cache_hwparams(dwc);
 
-	dwc3_phy_setup(dwc);
+	ret = dwc3_phy_setup(dwc);
+	if (ret)
+		goto err0;
 
 	ret = dwc3_core_get_phy(dwc);
 	if (ret)
@@ -994,6 +1020,7 @@ err2:
 
 err1:
 	dwc3_free_event_buffers(dwc);
+	dwc3_ulpi_exit(dwc);
 
 err0:
 	/*
@@ -1029,6 +1056,7 @@ static int dwc3_remove(struct platform_device *pdev)
 	phy_power_off(dwc->usb3_generic_phy);
 
 	dwc3_core_exit(dwc);
+	dwc3_ulpi_exit(dwc);
 
 	pm_runtime_put_sync(&pdev->dev);
 	pm_runtime_disable(&pdev->dev);