usb: phy: phy-am335x: bypass first VBUS sensing for host-only mode

To prevent VBUS contention, the am335x MUSB phy senses VBUS first before
transitioning to host mode. However, for host-only mode, VBUS could be
directly tied to 5V power rail which could prevent MUSB transitions to
host mode.

This change receives dr_mode of the controller then bypass the first
VBUS sensing for host-only mode, so that MUSB can work in host mode
event if VBUS is tied to 5V.
Signed-off-by: Bin Liu <b-liu@ti.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

drivers/usb/phy/Kconfig

@@ -66,6 +66,7 @@ config AM335X_PHY_USB
 	select USB_PHY
 	select AM335X_CONTROL_USB
 	select NOP_USB_XCEIV
+	select USB_COMMON
 	help
 	  This driver provides PHY support for that phy which part for the
 	  AM335x SoC.

drivers/usb/phy/phy-am335x-control.c

@@ -4,6 +4,7 @@
 #include <linux/of.h>
 #include <linux/io.h>
 #include <linux/delay.h>
+#include <linux/usb/otg.h>
 #include "phy-am335x-control.h"
 
 struct am335x_control_usb {
@@ -58,7 +59,8 @@ static void am335x_phy_wkup(struct  phy_control *phy_ctrl, u32 id, bool on)
 	spin_unlock(&usb_ctrl->lock);
 }
 
-static void am335x_phy_power(struct phy_control *phy_ctrl, u32 id, bool on)
+static void am335x_phy_power(struct phy_control *phy_ctrl, u32 id,
+				enum usb_dr_mode dr_mode, bool on)
 {
 	struct am335x_control_usb *usb_ctrl;
 	u32 val;
@@ -80,8 +82,14 @@ static void am335x_phy_power(struct phy_control *phy_ctrl, u32 id, bool on)
 
 	val = readl(usb_ctrl->phy_reg + reg);
 	if (on) {
-		val &= ~(USBPHY_CM_PWRDN | USBPHY_OTG_PWRDN);
-		val |= USBPHY_OTGVDET_EN | USBPHY_OTGSESSEND_EN;
+		if (dr_mode == USB_DR_MODE_HOST) {
+			val &= ~(USBPHY_CM_PWRDN | USBPHY_OTG_PWRDN |
+					USBPHY_OTGVDET_EN);
+			val |= USBPHY_OTGSESSEND_EN;
+		} else {
+			val &= ~(USBPHY_CM_PWRDN | USBPHY_OTG_PWRDN);
+			val |= USBPHY_OTGVDET_EN | USBPHY_OTGSESSEND_EN;
+		}
 	} else {
 		val |= USBPHY_CM_PWRDN | USBPHY_OTG_PWRDN;
 	}

drivers/usb/phy/phy-am335x-control.h

@@ -2,13 +2,15 @@
 #define _AM335x_PHY_CONTROL_H_
 
 struct phy_control {
-	void (*phy_power)(struct phy_control *phy_ctrl, u32 id, bool on);
+	void (*phy_power)(struct phy_control *phy_ctrl, u32 id,
+			enum usb_dr_mode dr_mode, bool on);
 	void (*phy_wkup)(struct phy_control *phy_ctrl, u32 id, bool on);
 };
 
-static inline void phy_ctrl_power(struct phy_control *phy_ctrl, u32 id, bool on)
+static inline void phy_ctrl_power(struct phy_control *phy_ctrl, u32 id,
+				enum usb_dr_mode dr_mode, bool on)
 {
-	phy_ctrl->phy_power(phy_ctrl, id, on);
+	phy_ctrl->phy_power(phy_ctrl, id, dr_mode, on);
 }
 
 static inline void phy_ctrl_wkup(struct phy_control *phy_ctrl, u32 id, bool on)

drivers/usb/phy/phy-am335x.c

@@ -8,6 +8,7 @@
 #include <linux/regulator/consumer.h>
 #include <linux/of.h>
 #include <linux/of_address.h>
+#include <linux/usb/of.h>
 
 #include "phy-am335x-control.h"
 #include "phy-generic.h"
@@ -16,13 +17,14 @@ struct am335x_phy {
 	struct usb_phy_generic usb_phy_gen;
 	struct phy_control *phy_ctrl;
 	int id;
+	enum usb_dr_mode dr_mode;
 };
 
 static int am335x_init(struct usb_phy *phy)
 {
 	struct am335x_phy *am_phy = dev_get_drvdata(phy->dev);
 
-	phy_ctrl_power(am_phy->phy_ctrl, am_phy->id, true);
+	phy_ctrl_power(am_phy->phy_ctrl, am_phy->id, am_phy->dr_mode, true);
 	return 0;
 }
 
@@ -30,7 +32,7 @@ static void am335x_shutdown(struct usb_phy *phy)
 {
 	struct am335x_phy *am_phy = dev_get_drvdata(phy->dev);
 
-	phy_ctrl_power(am_phy->phy_ctrl, am_phy->id, false);
+	phy_ctrl_power(am_phy->phy_ctrl, am_phy->id, am_phy->dr_mode, false);
 }
 
 static int am335x_phy_probe(struct platform_device *pdev)
@@ -46,12 +48,15 @@ static int am335x_phy_probe(struct platform_device *pdev)
 	am_phy->phy_ctrl = am335x_get_phy_control(dev);
 	if (!am_phy->phy_ctrl)
 		return -EPROBE_DEFER;
+
 	am_phy->id = of_alias_get_id(pdev->dev.of_node, "phy");
 	if (am_phy->id < 0) {
 		dev_err(&pdev->dev, "Missing PHY id: %d\n", am_phy->id);
 		return am_phy->id;
 	}
 
+	am_phy->dr_mode = of_usb_get_dr_mode_by_phy(pdev->dev.of_node);
+
 	ret = usb_phy_gen_create_phy(dev, &am_phy->usb_phy_gen, NULL);
 	if (ret)
 		return ret;
@@ -75,7 +80,7 @@ static int am335x_phy_probe(struct platform_device *pdev)
 	 */
 
 	device_set_wakeup_enable(dev, false);
-	phy_ctrl_power(am_phy->phy_ctrl, am_phy->id, false);
+	phy_ctrl_power(am_phy->phy_ctrl, am_phy->id, am_phy->dr_mode, false);
 
 	return 0;
 }
@@ -105,7 +110,7 @@ static int am335x_phy_suspend(struct device *dev)
 	if (device_may_wakeup(dev))
 		phy_ctrl_wkup(am_phy->phy_ctrl, am_phy->id, true);
 
-	phy_ctrl_power(am_phy->phy_ctrl, am_phy->id, false);
+	phy_ctrl_power(am_phy->phy_ctrl, am_phy->id, am_phy->dr_mode, false);
 
 	return 0;
 }
@@ -115,7 +120,7 @@ static int am335x_phy_resume(struct device *dev)
 	struct platform_device	*pdev = to_platform_device(dev);
 	struct am335x_phy	*am_phy = platform_get_drvdata(pdev);
 
-	phy_ctrl_power(am_phy->phy_ctrl, am_phy->id, true);
+	phy_ctrl_power(am_phy->phy_ctrl, am_phy->id, am_phy->dr_mode, true);
 
 	if (device_may_wakeup(dev))
 		phy_ctrl_wkup(am_phy->phy_ctrl, am_phy->id, false);