sunxi: musb: Power off OTG port VBUS when disabled

The Linux kernel musb driver expects VBUS to be off while initializing
musb. Having it on results in a repeating string of warnings, followed
by an unusable peripheral. The peripheral is only usable after
physically removing the OTG adapter, letting musb reset its state.

This partially reverts commit c9f8947e6604 ("sunxi: usb-phy: Never
power off the usb ports")

Signed-off-by: Chen-Yu Tsai <wens@csie.org>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>

arch/arm/include/asm/arch-sunxi/usb_phy.h

@@ -16,7 +16,6 @@ void sunxi_usb_phy_init(int index);
 void sunxi_usb_phy_exit(int index);
 void sunxi_usb_phy_power_on(int index);
 void sunxi_usb_phy_power_off(int index);
-int sunxi_usb_phy_power_is_on(int index);
 int sunxi_usb_phy_vbus_detect(int index);
 int sunxi_usb_phy_id_detect(int index);
 void sunxi_usb_phy_enable_squelch_detect(int index, int enable);

arch/arm/mach-sunxi/usb_phy.c

@@ -296,13 +296,6 @@ void sunxi_usb_phy_power_off(int index)
 		gpio_set_value(phy->gpio_vbus, 0);
 }
 
-int sunxi_usb_phy_power_is_on(int index)
-{
-	struct sunxi_usb_phy *phy = &sunxi_usb_phy[index];
-
-	return phy->power_on_count > 0;
-}
-
 int sunxi_usb_phy_vbus_detect(int index)
 {
 	struct sunxi_usb_phy *phy = &sunxi_usb_phy[index];

drivers/usb/musb-new/sunxi.c

@@ -205,6 +205,8 @@ static struct musb *sunxi_musb;
 
 static int sunxi_musb_enable(struct musb *musb)
 {
+	int ret;
+
 	pr_debug("%s():\n", __func__);
 
 	musb_ep_select(musb->mregs, 0);
@@ -217,26 +219,17 @@ static int sunxi_musb_enable(struct musb *musb)
 	musb_writeb(musb->mregs, USBC_REG_o_VEND0, 0);
 
 	if (is_host_enabled(musb)) {
-		int id = sunxi_usb_phy_id_detect(0);
-
-		if (id == 1 && sunxi_usb_phy_power_is_on(0))
-			sunxi_usb_phy_power_off(0);
-
-		if (!sunxi_usb_phy_power_is_on(0)) {
-			int vbus = sunxi_usb_phy_vbus_detect(0);
-			if (vbus == 1) {
-				printf("A charger is plugged into the OTG: ");
-				return -ENODEV;
-			}
+		ret = sunxi_usb_phy_vbus_detect(0);
+		if (ret == 1) {
+			printf("A charger is plugged into the OTG: ");
+			return -ENODEV;
 		}
-
-		if (id == 1) {
+		ret = sunxi_usb_phy_id_detect(0);
+		if (ret == 1) {
 			printf("No host cable detected: ");
 			return -ENODEV;
 		}
-
-		if (!sunxi_usb_phy_power_is_on(0))
-			sunxi_usb_phy_power_on(0);
+		sunxi_usb_phy_power_on(0); /* port power on */
 	}
 
 	USBC_ForceVbusValidToHigh(musb->mregs);
@@ -252,6 +245,9 @@ static void sunxi_musb_disable(struct musb *musb)
 	if (!enabled)
 		return;
 
+	if (is_host_enabled(musb))
+		sunxi_usb_phy_power_off(0); /* port power off */
+
 	USBC_ForceVbusValidToLow(musb->mregs);
 	mdelay(200); /* Wait for the current session to timeout */