lantiq: Configure gpio power output pin when initializing dwc2 usb

Port gpio code from original ltq-hcd driver to dwc2.

Signed-off-by: Antti Seppälä <a.seppala@gmail.com>
Signed-off-by: Vincent Pelletier <plr.vincent@gmail.com>

SVN-Revision: 44673

target/linux/lantiq/patches-3.18/0040-USB-DWC2-enable-usb-power-gpio.patch

@@ -0,0 +1,35 @@
+--- a/drivers/usb/dwc2/platform.c	2015-02-06 16:53:48.000000000 +0200
++++ b/drivers/usb/dwc2/platform.c	2015-02-09 19:22:41.974089626 +0200
+@@ -40,6 +40,7 @@
+ #include <linux/device.h>
+ #include <linux/dma-mapping.h>
+ #include <linux/of_device.h>
++#include <linux/of_gpio.h>
+ #include <linux/platform_device.h>
+ 
+ #include <linux/usb/of.h>
+@@ -154,6 +155,7 @@
+ 	struct resource *res;
+ 	int retval;
+ 	int irq;
++	int gpio_count;
+ 
+ 	if (usb_disabled())
+ 		return -ENODEV;
+@@ -173,6 +175,16 @@
+ 		defparams.dma_desc_enable = 0;
+ 	}
+ 
++	gpio_count = of_gpio_count(dev->dev.of_node);
++	while (gpio_count > 0) {
++		enum of_gpio_flags flags;
++		int gpio = of_get_gpio_flags(dev->dev.of_node, --gpio_count, &flags);
++		if (gpio_request(gpio, "usb"))
++			continue;
++		dev_info(&dev->dev, "requested GPIO %d\n", gpio);
++		gpio_direction_output(gpio, (flags & OF_GPIO_ACTIVE_LOW) ? (0) : (1));
++	}
++
+ 	hsotg = devm_kzalloc(&dev->dev, sizeof(*hsotg), GFP_KERNEL);
+ 	if (!hsotg)
+ 		return -ENOMEM;