On Wed, Nov 21, 2018 at 10:26:30AM +0100, Marek Szyprowski wrote: > On 2018-11-20 18:25, Marek Szyprowski wrote: > > On 2018-11-20 18:01, Charles Keepax wrote: > > ------------[ cut here ]------------ > > WARNING: CPU: 0 PID: 1 at drivers/gpio/gpiolib.c:2421 > > regulator_ena_gpio_free+0x70/0xa0 > > I've checked a bit more and it looks that the issue is caused by > gpiod_put() in regulator_ena_gpio_free(). I've removed gpiod_put() call > from wm8994_ldo_remove(), switched to regulator_register() in > wm8994_ldo_probe() and added regulator_unregister() in > wm8994_ldo_remove(). This way the warning is gone. If there is any > other, simpler way to fix it, let me know. When regulator_register() > fails, gpiod will be freed only in some cases, depending what caused > failure. It looks that this needs some clarification... >
Ah.. ok, so is perhaps what is happening here that both the devm_gpio_get and the regualtor_ena_gpio_free are both trying to free the GPIO? I assume the regulator core does this to handle the case of shared GPIOs, so presumably the correct fix would just be to switch from devm_gpiod_get to just plain gpiod_get and not add the additional gpiod_put in wm8994_ldo_remove, as the regulator core will handle freeing the GPIO for us. I will respin the patch and lets see where that gets us to. Thanks, Charles
