net: rfkill: gpio: set GPIO direction

Fix the undefined usage of the GPIO consumer API after retrieving the
GPIO description with GPIO_ASIS. The API documentation mentions that
GPIO_ASIS won't set a GPIO direction and requires the user to set a
direction before using the GPIO.

This can be confirmed on i.MX6 hardware, where rfkill-gpio is no longer
able to enabled/disable a device, presumably because the GPIO controller
was never configured for the output direction.

Fixes: b2f750c3a80b ("net: rfkill: gpio: prevent value glitch during probe")
Cc: stable@vger.kernel.org
Signed-off-by: Rouven Czerwinski <r.czerwinski@pengutronix.de>
Link: https://msgid.link/20231207075835.3091694-1-r.czerwinski@pengutronix.de
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

diff --git a/net/rfkill/rfkill-gpio.c b/net/rfkill/rfkill-gpio.c
index 5a81505fba9ac4091ad5ac968018979d50876c86..4e32d659524e0d82c85cd4c82132cf18c24c3adf 100644 (file)
--- a/net/rfkill/rfkill-gpio.c
+++ b/net/rfkill/rfkill-gpio.c
@@ -126,6 +126,14 @@ static int rfkill_gpio_probe(struct platform_device *pdev)
                return -EINVAL;
        }
 
+       ret = gpiod_direction_output(rfkill->reset_gpio, true);
+       if (ret)
+               return ret;
+
+       ret = gpiod_direction_output(rfkill->shutdown_gpio, true);
+       if (ret)
+               return ret;
+
        rfkill->rfkill_dev = rfkill_alloc(rfkill->name, &pdev->dev,
                                          rfkill->type, &rfkill_gpio_ops,
                                          rfkill);