serial: mctrl_gpio: use gpiod_set_array function

Make the serial_mctrl_gpio driver the first user of the new gpiod_set_array
function, which is now available in the linux-gpio devel tree.
All modem control output signals are now set simultaneously.
Signed-off-by: NRojhalat Ibrahim <imr@rtschenk.de>
Reviewed-by: NAlexandre Courbot <acourbot@nvidia.com>
Acked-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

drivers/tty/serial/serial_mctrl_gpio.c

@@ -44,15 +44,21 @@ static const struct {
 void mctrl_gpio_set(struct mctrl_gpios *gpios, unsigned int mctrl)
 {
 	enum mctrl_gpio_idx i;
+	struct gpio_desc *desc_array[UART_GPIO_MAX];
+	int value_array[UART_GPIO_MAX];
+	unsigned int count = 0;
 
 	if (IS_ERR_OR_NULL(gpios))
 		return;
 
 	for (i = 0; i < UART_GPIO_MAX; i++)
 		if (!IS_ERR_OR_NULL(gpios->gpio[i]) &&
-		    mctrl_gpios_desc[i].dir_out)
-			gpiod_set_value(gpios->gpio[i],
-					!!(mctrl & mctrl_gpios_desc[i].mctrl));
+		    mctrl_gpios_desc[i].dir_out) {
+			desc_array[count] = gpios->gpio[i];
+			value_array[count] = !!(mctrl & mctrl_gpios_desc[i].mctrl);
+			count++;
+		}
+	gpiod_set_array(count, desc_array, value_array);
 }
 EXPORT_SYMBOL_GPL(mctrl_gpio_set);