USB: bcma: switch to GPIO descriptor for power control

So far we were using simple (legacy) GPIO functions & some poor logic to
control power. It got many drawbacks: we were ignoring OF flags
(GPIO_ACTIVE_LOW), we were not setting direction to output and we were
assuming gpio_request success all the time.
Fix it by switching to gpiod functions and adding appropriate checks.
Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
Acked-by: Hauke Mehrtens <hauke@hauke-m.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/host/bcma-hcd.c

@@ -21,6 +21,7 @@
  */
 #include <linux/bcma/bcma.h>
 #include <linux/delay.h>
+#include <linux/gpio/consumer.h>
 #include <linux/platform_device.h>
 #include <linux/module.h>
 #include <linux/slab.h>
@@ -36,6 +37,7 @@ MODULE_LICENSE("GPL");
 struct bcma_hcd_device {
 	struct platform_device *ehci_dev;
 	struct platform_device *ohci_dev;
+	struct gpio_desc *gpio_desc;
 };
 
 /* Wait for bitmask in a register to get set or cleared.
@@ -228,19 +230,12 @@ static void bcma_hcd_init_chip_arm(struct bcma_device *dev)
 
 static void bcma_hci_platform_power_gpio(struct bcma_device *dev, bool val)
 {
-	int gpio;
+	struct bcma_hcd_device *usb_dev = bcma_get_drvdata(dev);
 
-	gpio = of_get_named_gpio(dev->dev.of_node, "vcc-gpio", 0);
-	if (!gpio_is_valid(gpio))
+	if (IS_ERR_OR_NULL(usb_dev->gpio_desc))
 		return;
 
-	if (val) {
-		gpio_request(gpio, "bcma-hcd-gpio");
-		gpio_set_value(gpio, 1);
-	} else {
-		gpio_set_value(gpio, 0);
-		gpio_free(gpio);
-	}
+	gpiod_set_value(usb_dev->gpio_desc, val);
 }
 
 static const struct usb_ehci_pdata ehci_pdata = {
@@ -314,7 +309,11 @@ static int bcma_hcd_probe(struct bcma_device *dev)
 	if (!usb_dev)
 		return -ENOMEM;
 
-	bcma_hci_platform_power_gpio(dev, true);
+	if (dev->dev.of_node)
+		usb_dev->gpio_desc = devm_get_gpiod_from_child(&dev->dev, "vcc",
+							       &dev->dev.of_node->fwnode);
+	if (!IS_ERR_OR_NULL(usb_dev->gpio_desc))
+		gpiod_direction_output(usb_dev->gpio_desc, 1);
 
 	switch (dev->id.id) {
 	case BCMA_CORE_NS_USB20: