ARM: tegra: add USB ULPI PHY reset GPIO to device tree

ULPI PHYs have a reset signal, and different boards use a different GPIO
for this task. Add a property to device tree to represent this.

I'm not sure if adding this property to the EHCI controller node is
entirely correct; perhaps eventually we should have explicit separate
nodes for the various PHYs. However, we don't have that right now, so this
binding seems like a reasonable choice.

Cc: <devicetree-discuss@lists.ozlabs.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: <linux-usb@vger.kernel.org>
Signed-off-by: Stephen Warren <swarren@nvidia.com>

9 files changed, 41 insertions, 6 deletions

diff --git a/Documentation/devicetree/bindings/usb/tegra-usb.txt b/Documentation/devicetree/bindings/usb/tegra-usb.txt
index 007005ddbe12..e9b005dc7625 100644
--- a/Documentation/devicetree/bindings/usb/tegra-usb.txt
+++ b/Documentation/devicetree/bindings/usb/tegra-usb.txt
@@ -12,6 +12,9 @@ Required properties :
  - nvidia,vbus-gpio : If present, specifies a gpio that needs to be
    activated for the bus to be powered.
 
+Required properties for phy_type == ulpi:
+  - nvidia,phy-reset-gpio : The GPIO used to reset the PHY.
+
 Optional properties:
   - dr_mode : dual role mode. Indicates the working mode for
    nvidia,tegra20-ehci compatible controllers.  Can be "host", "peripheral",
diff --git a/arch/arm/boot/dts/tegra-harmony.dts b/arch/arm/boot/dts/tegra-harmony.dts
index 1a0b1f182944..59bf1cf6a65c 100644
--- a/arch/arm/boot/dts/tegra-harmony.dts
+++ b/arch/arm/boot/dts/tegra-harmony.dts
@@ -336,4 +336,8 @@
                 power-gpios = <&gpio 70 0>; /* gpio PI6 */
                 support-8bit;
         };
+
+        usb@c5004000 {
+                nvidia,phy-reset-gpio = <&gpio 169 0>; /* gpio PV1 */
+        };
 };
diff --git a/arch/arm/boot/dts/tegra-paz00.dts b/arch/arm/boot/dts/tegra-paz00.dts
index 10943fb2561c..fad92f2dbff0 100644
--- a/arch/arm/boot/dts/tegra-paz00.dts
+++ b/arch/arm/boot/dts/tegra-paz00.dts
@@ -351,4 +351,8 @@
                         linux,default-trigger = "rfkill0";
                 };
         };
+
+        usb@c5004000 {
+                nvidia,phy-reset-gpio = <&gpio 168 0>; /* gpio PV0 */
+        };
 };
diff --git a/arch/arm/boot/dts/tegra-seaboard.dts b/arch/arm/boot/dts/tegra-seaboard.dts
index ec33116f5df9..ed0a2f5bf918 100644
--- a/arch/arm/boot/dts/tegra-seaboard.dts
+++ b/arch/arm/boot/dts/tegra-seaboard.dts
@@ -415,4 +415,8 @@
                                 0x00000000 0x00000000 0x00000000 0x00000000 >;
                 };
         };
+
+        usb@c5004000 {
+                nvidia,phy-reset-gpio = <&gpio 169 0>; /* gpio PV1 */
+        };
 };
diff --git a/arch/arm/boot/dts/tegra-trimslice.dts b/arch/arm/boot/dts/tegra-trimslice.dts
index 98efd5b0d7f9..71b73aab87ff 100644
--- a/arch/arm/boot/dts/tegra-trimslice.dts
+++ b/arch/arm/boot/dts/tegra-trimslice.dts
@@ -304,4 +304,8 @@
                 cd-gpios = <&gpio 121 0>;
                 wp-gpios = <&gpio 122 0>;
         };
+
+        usb@c5004000 {
+                nvidia,phy-reset-gpio = <&gpio 168 0>; /* gpio PV0 */
+        };
 };
diff --git a/arch/arm/boot/dts/tegra-ventana.dts b/arch/arm/boot/dts/tegra-ventana.dts
index 71eb2e50a668..bd074cfb338f 100644
--- a/arch/arm/boot/dts/tegra-ventana.dts
+++ b/arch/arm/boot/dts/tegra-ventana.dts
@@ -335,4 +335,8 @@
         sdhci@c8000600 {
                 support-8bit;
         };
+
+        usb@c5004000 {
+                nvidia,phy-reset-gpio = <&gpio 169 0>; /* gpio PV1 */
+        };
 };
diff --git a/arch/arm/mach-tegra/include/mach/usb_phy.h b/arch/arm/mach-tegra/include/mach/usb_phy.h
index de1a0f602b28..935ce9f65590 100644
--- a/arch/arm/mach-tegra/include/mach/usb_phy.h
+++ b/arch/arm/mach-tegra/include/mach/usb_phy.h
@@ -61,8 +61,8 @@ struct tegra_usb_phy {
         struct usb_phy *ulpi;
 };
 
-struct tegra_usb_phy *tegra_usb_phy_open(int instance, void __iomem *regs,
-                        void *config, enum tegra_usb_phy_mode phy_mode);
+struct tegra_usb_phy *tegra_usb_phy_open(struct device *dev, int instance,
+        void __iomem *regs, void *config, enum tegra_usb_phy_mode phy_mode);
 
 int tegra_usb_phy_power_on(struct tegra_usb_phy *phy);
 
diff --git a/arch/arm/mach-tegra/usb_phy.c b/arch/arm/mach-tegra/usb_phy.c
index d71d2fed6721..54e353c8e304 100644
--- a/arch/arm/mach-tegra/usb_phy.c
+++ b/arch/arm/mach-tegra/usb_phy.c
@@ -26,6 +26,7 @@
 #include <linux/platform_device.h>
 #include <linux/io.h>
 #include <linux/gpio.h>
+#include <linux/of_gpio.h>
 #include <linux/usb/otg.h>
 #include <linux/usb/ulpi.h>
 #include <asm/mach-types.h>
@@ -654,8 +655,8 @@ static void ulpi_phy_power_off(struct tegra_usb_phy *phy)
         clk_disable(phy->clk);
 }
 
-struct tegra_usb_phy *tegra_usb_phy_open(int instance, void __iomem *regs,
-                        void *config, enum tegra_usb_phy_mode phy_mode)
+struct tegra_usb_phy *tegra_usb_phy_open(struct device *dev, int instance,
+        void __iomem *regs, void *config, enum tegra_usb_phy_mode phy_mode)
 {
         struct tegra_usb_phy *phy;
         struct tegra_ulpi_config *ulpi_config;
@@ -711,6 +712,16 @@ struct tegra_usb_phy *tegra_usb_phy_open(int instance, void __iomem *regs,
                         err = -ENXIO;
                         goto err1;
                 }
+                if (!gpio_is_valid(ulpi_config->reset_gpio))
+                        ulpi_config->reset_gpio =
+                                of_get_named_gpio(dev->of_node,
+                                                  "nvidia,phy-reset-gpio", 0);
+                if (!gpio_is_valid(ulpi_config->reset_gpio)) {
+                        pr_err("%s: invalid reset gpio: %d\n", __func__,
+                               ulpi_config->reset_gpio);
+                        err = -EINVAL;
+                        goto err1;
+                }
                 gpio_request(ulpi_config->reset_gpio, "ulpi_phy_reset_b");
                 gpio_direction_output(ulpi_config->reset_gpio, 0);
                 phy->ulpi = otg_ulpi_create(&ulpi_viewport_access_ops, 0);
diff --git a/drivers/usb/host/ehci-tegra.c b/drivers/usb/host/ehci-tegra.c
index 9692bef159f5..14532fe04f5e 100644
--- a/drivers/usb/host/ehci-tegra.c
+++ b/drivers/usb/host/ehci-tegra.c
@@ -708,8 +708,9 @@ static int tegra_ehci_probe(struct platform_device *pdev)
                 }
         }
 
-        tegra->phy = tegra_usb_phy_open(instance, hcd->regs, pdata->phy_config,
-                                                TEGRA_USB_PHY_MODE_HOST);
+        tegra->phy = tegra_usb_phy_open(&pdev->dev, instance, hcd->regs,
+                                        pdata->phy_config,
+                                        TEGRA_USB_PHY_MODE_HOST);
         if (IS_ERR(tegra->phy)) {
                 dev_err(&pdev->dev, "Failed to open USB phy\n");
                 err = -ENXIO;