phy: tusb1210: make better use of gpiod API

Since 39b2bbe3 (gpio: add flags argument to gpiod_get*() functions)
which appeared in v3.17-rc1, the gpiod_get* functions take an additional
parameter that allows to specify direction and initial value for output.

Furthermore there is devm_gpiod_get_optional which is designed to get
optional gpios.

Simplify driver accordingly.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>

drivers/phy/phy-tusb1210.c

@@ -61,32 +61,26 @@ static struct phy_ops phy_ops = {
 
 static int tusb1210_probe(struct ulpi *ulpi)
 {
-	struct gpio_desc *gpio;
 	struct tusb1210 *tusb;
 	u8 val, reg;
-	int ret;
 
 	tusb = devm_kzalloc(&ulpi->dev, sizeof(*tusb), GFP_KERNEL);
 	if (!tusb)
 		return -ENOMEM;
 
-	gpio = devm_gpiod_get(&ulpi->dev, "reset");
-	if (!IS_ERR(gpio)) {
-		ret = gpiod_direction_output(gpio, 0);
-		if (ret)
-			return ret;
-		gpiod_set_value_cansleep(gpio, 1);
-		tusb->gpio_reset = gpio;
-	}
+	tusb->gpio_reset = devm_gpiod_get_optional(&ulpi->dev, "reset",
+						   GPIOD_OUT_LOW);
+	if (IS_ERR(tusb->gpio_reset))
+		return PTR_ERR(tusb->gpio_reset);
 
-	gpio = devm_gpiod_get(&ulpi->dev, "cs");
-	if (!IS_ERR(gpio)) {
-		ret = gpiod_direction_output(gpio, 0);
-		if (ret)
-			return ret;
-		gpiod_set_value_cansleep(gpio, 1);
-		tusb->gpio_cs = gpio;
-	}
+	gpiod_set_value_cansleep(tusb->gpio_reset, 1);
+
+	tusb->gpio_cs = devm_gpiod_get_optional(&ulpi->dev, "cs",
+						GPIOD_OUT_LOW);
+	if (IS_ERR(tusb->gpio_cs))
+		return PTR_ERR(tusb->gpio_cs);
+
+	gpiod_set_value_cansleep(tusb->gpio_cs, 1);
 
 	/*
 	 * VENDOR_SPECIFIC2 register in TUSB1210 can be used for configuring eye