USB: ehci-s5p: Add vbus setup function to the s5p ehci glue layer

This patch retrieves and configures the vbus control gpio via
the device tree. The suspend/resume callbacks will be later
modified for vbus control.
Signed-off-by: Abhilash Kesavan <a.kesavan@samsung.com>
Signed-off-by: Vivek Gautam <gautam.vivek@samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/host/ehci-s5p.c

@@ -15,6 +15,7 @@
 #include <linux/clk.h>
 #include <linux/of.h>
 #include <linux/platform_device.h>
+#include <linux/of_gpio.h>
 #include <plat/ehci.h>
 #include <plat/usb-phy.h>
 
@@ -64,6 +65,24 @@ static const struct hc_driver s5p_ehci_hc_driver = {
 	.clear_tt_buffer_complete	= ehci_clear_tt_buffer_complete,
 };
 
+static void s5p_setup_vbus_gpio(struct platform_device *pdev)
+{
+	int err;
+	int gpio;
+
+	if (!pdev->dev.of_node)
+		return;
+
+	gpio = of_get_named_gpio(pdev->dev.of_node,
+			"samsung,vbus-gpio", 0);
+	if (!gpio_is_valid(gpio))
+		return;
+
+	err = gpio_request_one(gpio, GPIOF_OUT_INIT_HIGH, "ehci_vbus_gpio");
+	if (err)
+		dev_err(&pdev->dev, "can't request ehci vbus gpio %d", gpio);
+}
+
 static u64 ehci_s5p_dma_mask = DMA_BIT_MASK(32);
 
 static int __devinit s5p_ehci_probe(struct platform_device *pdev)
@@ -92,6 +111,8 @@ static int __devinit s5p_ehci_probe(struct platform_device *pdev)
 	if (!pdev->dev.coherent_dma_mask)
 		pdev->dev.coherent_dma_mask = DMA_BIT_MASK(32);
 
+	s5p_setup_vbus_gpio(pdev);
+
 	s5p_ehci = devm_kzalloc(&pdev->dev, sizeof(struct s5p_ehci_hcd),
 				GFP_KERNEL);
 	if (!s5p_ehci)