usb: dwc3: meson-g12a: refactor usb init

Refactor the USB init code patch to handle the Amlogic GXL/GXM needing
to initialize the OTG port as Peripheral mode for the DWC2 IP to probe
correctly.

A secondary, post_init callback is added to setup the OTG PHY mode after
powering up the PHYs and before probing the DWC2 and DWC3 controllers.
Reviewed-by: NMartin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: NNeil Armstrong <narmstrong@baylibre.com>
Signed-off-by: NFelipe Balbi <balbi@kernel.org>

drivers/usb/dwc3/dwc3-meson-g12a.c

@@ -140,6 +140,8 @@ struct dwc3_meson_g12a_drvdata {
 			     enum phy_mode mode);
 	int (*set_phy_mode)(struct dwc3_meson_g12a *priv, int i,
 			    enum phy_mode mode);
+	int (*usb_init)(struct dwc3_meson_g12a *priv);
+	int (*usb_post_init)(struct dwc3_meson_g12a *priv);
 };
 
 static int dwc3_meson_g12a_setup_regmaps(struct dwc3_meson_g12a *priv,
@@ -151,6 +153,8 @@ static int dwc3_meson_g12a_usb2_init_phy(struct dwc3_meson_g12a *priv, int i,
 static int dwc3_meson_g12a_set_phy_mode(struct dwc3_meson_g12a *priv,
 					int i, enum phy_mode mode);
 
+static int dwc3_meson_g12a_usb_init(struct dwc3_meson_g12a *priv);
+
 static struct dwc3_meson_g12a_drvdata g12a_drvdata = {
 	.otg_switch_supported = true,
 	.clks = meson_g12a_clocks,
@@ -160,6 +164,7 @@ static struct dwc3_meson_g12a_drvdata g12a_drvdata = {
 	.setup_regmaps = dwc3_meson_g12a_setup_regmaps,
 	.usb2_init_phy = dwc3_meson_g12a_usb2_init_phy,
 	.set_phy_mode = dwc3_meson_g12a_set_phy_mode,
+	.usb_init = dwc3_meson_g12a_usb_init,
 };
 
 static struct dwc3_meson_g12a_drvdata a1_drvdata = {
@@ -171,6 +176,7 @@ static struct dwc3_meson_g12a_drvdata a1_drvdata = {
 	.setup_regmaps = dwc3_meson_g12a_setup_regmaps,
 	.usb2_init_phy = dwc3_meson_g12a_usb2_init_phy,
 	.set_phy_mode = dwc3_meson_g12a_set_phy_mode,
+	.usb_init = dwc3_meson_g12a_usb_init,
 };
 
 struct dwc3_meson_g12a {
@@ -231,15 +237,11 @@ static int dwc3_meson_g12a_usb2_init_phy(struct dwc3_meson_g12a *priv, int i,
 	return 0;
 }
 
-static int dwc3_meson_g12a_usb2_init(struct dwc3_meson_g12a *priv)
+static int dwc3_meson_g12a_usb2_init(struct dwc3_meson_g12a *priv,
+				     enum phy_mode mode)
 {
 	int i, ret;
 
-	if (priv->otg_mode == USB_DR_MODE_PERIPHERAL)
-		priv->otg_phy_mode = PHY_MODE_USB_DEVICE;
-	else
-		priv->otg_phy_mode = PHY_MODE_USB_HOST;
-
 	for (i = 0; i < priv->drvdata->num_phys; ++i) {
 		if (!priv->phys[i])
 			continue;
@@ -247,7 +249,7 @@ static int dwc3_meson_g12a_usb2_init(struct dwc3_meson_g12a *priv)
 		if (!strstr(priv->drvdata->phy_names[i], "usb2"))
 			continue;
 
-		ret = priv->drvdata->usb2_init_phy(priv, i, priv->otg_phy_mode);
+		ret = priv->drvdata->usb2_init_phy(priv, i, mode);
 		if (ret)
 			return ret;
 	}
@@ -284,9 +286,10 @@ static void dwc3_meson_g12a_usb3_init(struct dwc3_meson_g12a *priv)
 			FIELD_PREP(USB_R1_P30_PCS_TX_SWING_FULL_MASK, 127));
 }
 
-static void dwc3_meson_g12a_usb_otg_apply_mode(struct dwc3_meson_g12a *priv)
+static void dwc3_meson_g12a_usb_otg_apply_mode(struct dwc3_meson_g12a *priv,
+					       enum phy_mode mode)
 {
-	if (priv->otg_phy_mode == PHY_MODE_USB_DEVICE) {
+	if (mode == PHY_MODE_USB_DEVICE) {
 		regmap_update_bits(priv->usb_glue_regmap, USB_R0,
 				USB_R0_U2D_ACT, USB_R0_U2D_ACT);
 		regmap_update_bits(priv->usb_glue_regmap, USB_R0,
@@ -301,11 +304,12 @@ static void dwc3_meson_g12a_usb_otg_apply_mode(struct dwc3_meson_g12a *priv)
 	}
 }
 
-static int dwc3_meson_g12a_usb_init(struct dwc3_meson_g12a *priv)
+static int dwc3_meson_g12a_usb_init_glue(struct dwc3_meson_g12a *priv,
+					 enum phy_mode mode)
 {
 	int ret;
 
-	ret = dwc3_meson_g12a_usb2_init(priv);
+	ret = dwc3_meson_g12a_usb2_init(priv, mode);
 	if (ret)
 		return ret;
 
@@ -327,7 +331,7 @@ static int dwc3_meson_g12a_usb_init(struct dwc3_meson_g12a *priv)
 	if (priv->usb3_ports)
 		dwc3_meson_g12a_usb3_init(priv);
 
-	dwc3_meson_g12a_usb_otg_apply_mode(priv);
+	dwc3_meson_g12a_usb_otg_apply_mode(priv, mode);
 
 	return 0;
 }
@@ -406,7 +410,7 @@ static int dwc3_meson_g12a_otg_mode_set(struct dwc3_meson_g12a *priv,
 	if (ret)
 		return ret;
 
-	dwc3_meson_g12a_usb_otg_apply_mode(priv);
+	dwc3_meson_g12a_usb_otg_apply_mode(priv, mode);
 
 	return 0;
 }
@@ -555,6 +559,11 @@ static int dwc3_meson_g12a_setup_regmaps(struct dwc3_meson_g12a *priv,
 	return 0;
 }
 
+static int dwc3_meson_g12a_usb_init(struct dwc3_meson_g12a *priv)
+{
+	return dwc3_meson_g12a_usb_init_glue(priv, priv->otg_phy_mode);
+}
+
 static int dwc3_meson_g12a_probe(struct platform_device *pdev)
 {
 	struct dwc3_meson_g12a	*priv;
@@ -622,7 +631,12 @@ static int dwc3_meson_g12a_probe(struct platform_device *pdev)
 	/* Get dr_mode */
 	priv->otg_mode = usb_get_dr_mode(dev);
 
-	ret = dwc3_meson_g12a_usb_init(priv);
+	if (priv->otg_mode == USB_DR_MODE_PERIPHERAL)
+		priv->otg_phy_mode = PHY_MODE_USB_DEVICE;
+	else
+		priv->otg_phy_mode = PHY_MODE_USB_HOST;
+
+	ret = priv->drvdata->usb_init(priv);
 	if (ret)
 		goto err_disable_clks;
 
@@ -640,6 +654,12 @@ static int dwc3_meson_g12a_probe(struct platform_device *pdev)
 			goto err_phys_exit;
 	}
 
+	if (priv->drvdata->usb_post_init) {
+		ret = priv->drvdata->usb_post_init(priv);
+		if (ret)
+			goto err_phys_power;
+	}
+
 	ret = of_platform_populate(np, NULL, NULL, dev);
 	if (ret)
 		goto err_phys_power;
@@ -741,7 +761,9 @@ static int __maybe_unused dwc3_meson_g12a_resume(struct device *dev)
 
 	reset_control_deassert(priv->reset);
 
-	dwc3_meson_g12a_usb_init(priv);
+	ret = priv->drvdata->usb_init(priv);
+	if (ret)
+		return ret;
 
 	/* Init PHYs */
 	for (i = 0 ; i < PHY_COUNT ; ++i) {