gpio: pcf857x: use new GPIO line value setter callbacks

struct gpio_chip now has callbacks for setting line values that return
an integer, allowing to indicate failures. Convert the driver to using
them.

Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Bartosz Golaszewski <[e-mail]>

drivers/gpio/gpio-pcf857x.c

···
 	return status;
 }
 
-static void pcf857x_set(struct gpio_chip *chip, unsigned int offset, int value)
+static int pcf857x_set(struct gpio_chip *chip, unsigned int offset, int value)
 {
-	pcf857x_output(chip, offset, value);
+	return pcf857x_output(chip, offset, value);
 }
 
-static void pcf857x_set_multiple(struct gpio_chip *chip, unsigned long *mask,
-				 unsigned long *bits)
+static int pcf857x_set_multiple(struct gpio_chip *chip, unsigned long *mask,
+				unsigned long *bits)
 {
 	struct pcf857x *gpio = gpiochip_get_data(chip);
+	int status;
 
 	mutex_lock(&gpio->lock);
 	gpio->out &= ~*mask;
 	gpio->out |= *bits & *mask;
-	gpio->write(gpio->client, gpio->out);
+	status = gpio->write(gpio->client, gpio->out);
 	mutex_unlock(&gpio->lock);
+
+	return status;
 }
 
 /*-------------------------------------------------------------------------*/
···
 	gpio->chip.owner		= THIS_MODULE;
 	gpio->chip.get			= pcf857x_get;
 	gpio->chip.get_multiple		= pcf857x_get_multiple;
-	gpio->chip.set			= pcf857x_set;
-	gpio->chip.set_multiple		= pcf857x_set_multiple;
+	gpio->chip.set_rv		= pcf857x_set;
+	gpio->chip.set_multiple_rv	= pcf857x_set_multiple;
 	gpio->chip.direction_input	= pcf857x_input;
 	gpio->chip.direction_output	= pcf857x_output;
 	gpio->chip.ngpio		= (uintptr_t)i2c_get_match_data(client);