usb: tegra: Use regulators instead of GPIOs for USB PHY VBUS

The tegra ehci driver has enabled USB vbus regulators directly using
GPIOs and the device tree attribute nvidia,vbus-gpio. This is ugly
and causes error messages on boot when both the regulator driver
and the ehci driver want access to the same GPIO.

After this patch, usb vbus regulators for tegra usb phy devices are specified
with the device tree attribute vbus-supply = <&x> where x is a regulator defined
in the device tree. The old nvidia,vbus-gpio property is no longer supported.

Signed-off-by: Mikko Perttunen <mperttunen@nvidia.com>
Reviewed-by: Stephen Warren <swarren@nvidia.com>
Tested-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

1 files changed, 24 insertions, 0 deletions

diff --git a/drivers/usb/phy/phy-tegra-usb.c b/drivers/usb/phy/phy-tegra-usb.c
index 3ecd49871b88..d92a63a5b0c9 100644
--- a/drivers/usb/phy/phy-tegra-usb.c
+++ b/drivers/usb/phy/phy-tegra-usb.c
@@ -34,6 +34,7 @@
 #include <asm/mach-types.h>
 #include <linux/usb/ehci_def.h>
 #include <linux/usb/tegra_usb_phy.h>
+#include <linux/regulator/consumer.h>
 
 #define ULPI_VIEWPORT		0x170
 
@@ -613,6 +614,9 @@ static void tegra_usb_phy_close(struct usb_phy *x)
 {
 	struct tegra_usb_phy *phy = container_of(x, struct tegra_usb_phy, u_phy);
 
+	if (!IS_ERR(phy->vbus))
+		regulator_disable(phy->vbus);
+
 	clk_disable_unprepare(phy->pll_u);
 }
 
@@ -705,6 +709,16 @@ static int tegra_usb_phy_init(struct tegra_usb_phy *phy)
 		goto fail;
 	}
 
+	if (!IS_ERR(phy->vbus)) {
+		err = regulator_enable(phy->vbus);
+		if (err) {
+			dev_err(phy->dev,
+				"failed to enable usb vbus regulator: %d\n",
+				err);
+			goto fail;
+		}
+	}
+
 	if (phy->is_ulpi_phy)
 		err = ulpi_open(phy);
 	else
@@ -896,6 +910,16 @@ static int tegra_usb_phy_probe(struct platform_device *pdev)
 	} else
 		tegra_phy->mode = TEGRA_USB_PHY_MODE_OTG;
 
+	/* On some boards, the VBUS regulator doesn't need to be controlled */
+	if (of_find_property(np, "vbus-supply", NULL)) {
+		tegra_phy->vbus = devm_regulator_get(&pdev->dev, "vbus");
+		if (IS_ERR(tegra_phy->vbus))
+			return PTR_ERR(tegra_phy->vbus);
+	} else {
+		dev_notice(&pdev->dev, "no vbus regulator");
+		tegra_phy->vbus = ERR_PTR(-ENODEV);
+	}
+
 	tegra_phy->dev = &pdev->dev;
 	err = tegra_usb_phy_init(tegra_phy);
 	if (err < 0)