gnss: ubx: add support for the reset gpio

The Renesas KingFisher board includes a U-Blox Neo-M8 chip. This chip
has a reset pin which is also wired on the board. When Linux starts,
reset is asserted by the firmware. Deassert the reset pin when probing
this driver.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
[ johan: rename gpio descriptor variable ]
Signed-off-by: Johan Hovold <johan@kernel.org>
This commit is contained in:
Wolfram Sang 2023-11-12 19:51:51 -05:00 committed by Johan Hovold
parent aba9f8b07d
commit 0cbbbe09d4

View file

@ -7,6 +7,7 @@
#include <linux/errno.h>
#include <linux/gnss.h>
#include <linux/gpio/consumer.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/module.h>
@ -65,6 +66,7 @@ static const struct gnss_serial_ops ubx_gserial_ops = {
static int ubx_probe(struct serdev_device *serdev)
{
struct gnss_serial *gserial;
struct gpio_desc *reset;
struct ubx_data *data;
int ret;
@ -90,6 +92,13 @@ static int ubx_probe(struct serdev_device *serdev)
if (ret < 0 && ret != -ENODEV)
goto err_free_gserial;
/* Deassert reset */
reset = devm_gpiod_get_optional(&serdev->dev, "reset", GPIOD_OUT_LOW);
if (IS_ERR(reset)) {
ret = PTR_ERR(reset);
goto err_free_gserial;
}
ret = gnss_serial_register(gserial);
if (ret)
goto err_free_gserial;