[PATCH/RFC v2 2/9] phy: rcar-gen3-usb2: Add vbus-supply to handle VBUS on/off

[Yoshihiro Shimoda]

To handle the VBUS on/off by a regulator driver, this patch adds
regulator APIs calling in the driver and description about vbus-supply
in the rcar-gen3-phy-usb2.txt.

Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda...@renesas.com>
---
 .../devicetree/bindings/phy/rcar-gen3-phy-usb2.txt |  2 ++
 drivers/phy/phy-rcar-gen3-usb2.c                   | 28 ++++++++++++++++++++++
 2 files changed, 30 insertions(+)

diff --git a/Documentation/devicetree/bindings/phy/rcar-gen3-phy-usb2.txt 
b/Documentation/devicetree/bindings/phy/rcar-gen3-phy-usb2.txt
index eaf7e9b..2ffb856 100644
--- a/Documentation/devicetree/bindings/phy/rcar-gen3-phy-usb2.txt
+++ b/Documentation/devicetree/bindings/phy/rcar-gen3-phy-usb2.txt
@@ -15,6 +15,8 @@ To use a USB channel where USB 2.0 Host and HSUSB (USB 2.0 
Peripheral) are
 combined, the device tree node should set interrupt properties to use the
 channel as USB OTG:
 - interrupts: interrupt specifier for the PHY.
+- vbus-supply: Phandle to a regulator that provides power to the VBUS. This
+              regulator will be managed during the PHY power on/off sequence.
 
 Example (R-Car H3):
 
diff --git a/drivers/phy/phy-rcar-gen3-usb2.c b/drivers/phy/phy-rcar-gen3-usb2.c
index 2da2148..c2bfde8 100644
--- a/drivers/phy/phy-rcar-gen3-usb2.c
+++ b/drivers/phy/phy-rcar-gen3-usb2.c
@@ -19,6 +19,7 @@
 #include <linux/of_address.h>
 #include <linux/phy/phy.h>
 #include <linux/platform_device.h>
+#include <linux/regulator/consumer.h>
 
 /******* USB2.0 Host registers (original offset is +0x200) *******/
 #define USB2_INT_ENABLE                0x000
@@ -77,6 +78,7 @@
 struct rcar_gen3_chan {
        void __iomem *base;
        struct phy *phy;
+       struct regulator *vbus;
        bool has_otg;
 };
 
@@ -210,6 +212,13 @@ static int rcar_gen3_phy_usb2_power_on(struct phy *p)
        struct rcar_gen3_chan *channel = phy_get_drvdata(p);
        void __iomem *usb2_base = channel->base;
        u32 val;
+       int ret;
+
+       if (channel->vbus) {
+               ret = regulator_enable(channel->vbus);
+               if (ret)
+                       return ret;
+       }
 
        val = readl(usb2_base + USB2_USBCTR);
        val |= USB2_USBCTR_PLL_RST;
@@ -220,10 +229,22 @@ static int rcar_gen3_phy_usb2_power_on(struct phy *p)
        return 0;
 }
 
+static int rcar_gen3_phy_usb2_power_off(struct phy *p)
+{
+       struct rcar_gen3_chan *channel = phy_get_drvdata(p);
+       int ret = 0;
+
+       if (channel->vbus)
+               ret = regulator_disable(channel->vbus);
+
+       return ret;
+}
+
 static struct phy_ops rcar_gen3_phy_usb2_ops = {
        .init           = rcar_gen3_phy_usb2_init,
        .exit           = rcar_gen3_phy_usb2_exit,
        .power_on       = rcar_gen3_phy_usb2_power_on,
+       .power_off      = rcar_gen3_phy_usb2_power_off,
        .owner          = THIS_MODULE,
 };
 
@@ -289,6 +310,13 @@ static int rcar_gen3_phy_usb2_probe(struct platform_device 
*pdev)
                return PTR_ERR(channel->phy);
        }
 
+       channel->vbus = devm_regulator_get_optional(dev, "vbus");
+       if (IS_ERR(channel->vbus)) {
+               if (PTR_ERR(channel->vbus) == -EPROBE_DEFER)
+                       return PTR_ERR(channel->vbus);
+               channel->vbus = NULL;
+       }
+
        phy_set_drvdata(channel->phy, channel);
 
        provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate);
-- 
1.9.1