[PATCH 5.15.y 5/5] serial: sc16is7xx: implement gpio get_direction() callback

From: Hugo Villeneuve <[email protected]>

[ Upstream commit af071d9e07e57cfff239e8d09d2f3b05ebc9c667 ]

It's strongly recommended for GPIO drivers to always implement the
.get_direction() callback - even when the direction is tracked in
software. The GPIO core emits a warning when the callback is missing
and a user reads the direction of a line, e.g. via
/sys/kernel/debug/gpio.

Fixes: dfeae619d781 ("serial: sc16is7xx")
Cc: stable <[email protected]>
Signed-off-by: Hugo Villeneuve <[email protected]>
Acked-by: Bartosz Golaszewski <[email protected]>
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
---
 drivers/tty/serial/sc16is7xx.c | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/drivers/tty/serial/sc16is7xx.c b/drivers/tty/serial/sc16is7xx.c
index bd377488af6d2..e1bb025a700d1 100644
--- a/drivers/tty/serial/sc16is7xx.c
+++ b/drivers/tty/serial/sc16is7xx.c
@@ -1204,6 +1204,17 @@ static void sc16is7xx_gpio_set(struct gpio_chip *chip, unsigned offset, int val)
 			      val ? BIT(offset) : 0);
 }
 
+static int sc16is7xx_gpio_get_direction(struct gpio_chip *chip, unsigned int offset)
+{
+	struct sc16is7xx_port *s = gpiochip_get_data(chip);
+	struct uart_port *port = &s->p[0].port;
+	unsigned int val;
+
+	val = sc16is7xx_port_read(port, SC16IS7XX_IODIR_REG);
+
+	return val & BIT(offset) ? GPIO_LINE_DIRECTION_OUT : GPIO_LINE_DIRECTION_IN;
+}
+
 static int sc16is7xx_gpio_direction_input(struct gpio_chip *chip,
 					  unsigned offset)
 {
@@ -1281,6 +1292,7 @@ static int sc16is7xx_setup_gpio_chip(struct sc16is7xx_port *s)
 	s->gpio.parent		 = dev;
 	s->gpio.label		 = dev_name(dev);
 	s->gpio.init_valid_mask	 = sc16is7xx_gpio_init_valid_mask;
+	s->gpio.get_direction	 = sc16is7xx_gpio_get_direction;
 	s->gpio.direction_input	 = sc16is7xx_gpio_direction_input;
 	s->gpio.get		 = sc16is7xx_gpio_get;
 	s->gpio.direction_output = sc16is7xx_gpio_direction_output;
-- 
2.53.0