phy: sun4i-usb: Refactor VBUS detection to match Linux

The Linux driver checks the VBUS detection GPIO first; then VBUS power
supply; then finally assumes VBUS is present. When adding VBUS power
supply support, we want to match that order, so we get the same behavior
in case both a GPIO and a power supply are provided in the device tree.

So refactor the function a bit to remove the early return, and use the
same "assume VBUS is present" final fallback.

Signed-off-by: Samuel Holland <samuel@sholland.org>
Acked-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Andre Przywara <andre.przywara@arm.com>

diff --git a/drivers/phy/allwinner/phy-sun4i-usb.c b/drivers/phy/allwinner/phy-sun4i-usb.c
index 5302b809ee633d114b603ca8c4c115d960bcb826..827ecd70f276890e3521f765d6d4874a3fdcd795 100644 (file)
--- a/drivers/phy/allwinner/phy-sun4i-usb.c
+++ b/drivers/phy/allwinner/phy-sun4i-usb.c
@@ -391,20 +391,19 @@ int sun4i_usb_phy_vbus_detect(struct phy *phy)
 {
        struct sun4i_usb_phy_data *data = dev_get_priv(phy->dev);
        struct sun4i_usb_phy_plat *usb_phy = &data->usb_phy[phy->id];
-       int err, retries = 3;
-
-       if (usb_phy->gpio_vbus_det < 0)
-               return usb_phy->gpio_vbus_det;
-
-       err = gpio_get_value(usb_phy->gpio_vbus_det);
-       /*
-        * Vbus may have been provided by the board and just been turned of
-        * some milliseconds ago on reset, what we're measuring then is a
-        * residual charge on Vbus, sleep a bit and try again.
-        */
-       while (err > 0 && retries--) {
-               mdelay(100);
+       int err = 1, retries = 3;
+
+       if (usb_phy->gpio_vbus_det >= 0) {
                err = gpio_get_value(usb_phy->gpio_vbus_det);
+               /*
+                * Vbus may have been provided by the board and just turned off
+                * some milliseconds ago on reset. What we're measuring then is
+                * a residual charge on Vbus. Sleep a bit and try again.
+                */
+               while (err > 0 && retries--) {
+                       mdelay(100);
+                       err = gpio_get_value(usb_phy->gpio_vbus_det);
+               }
        }
 
        return err;