On Wed, 20 Aug 2014, Lothar Waßmann wrote:
> commit 257462dbf3ed ("pwm-backlight: switch to gpiod interface")
> introduced a regression leading to acquiring a bogus GPIO-0 when
> configured from DT without an 'enable-gpios' property.
> The driver will happily accept the 0 initialized 'enable_gpio' member
> of the struct platform_pwm_backlight_data as valid gpio number, and
> request this GPIO as enable pin. In case of multiple driver instances,
> the second will fail to register with the error message:
> pwm-backlight backlight1.23: failed to request GPIO#0: -16
>
> Fix this by setting enable_gpio in the pdata struct to -EINVAL.
>
> Signed-off-by: Lothar Waßmann <l...@karo-electronics.de>
> ---
> drivers/video/backlight/pwm_bl.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
Applied to -fixes with Thierry's Ack and the blank line left.
> diff --git a/drivers/video/backlight/pwm_bl.c
> b/drivers/video/backlight/pwm_bl.c
> index d7a3d13..e6ef6b4 100644
> --- a/drivers/video/backlight/pwm_bl.c
> +++ b/drivers/video/backlight/pwm_bl.c
> @@ -172,7 +172,7 @@ static int pwm_backlight_parse_dt(struct device *dev,
> data->dft_brightness = value;
> data->max_brightness--;
> }
> -
> + data->enable_gpio = -EINVAL;
> return 0;
> }
>
--
Lee Jones
Linaro STMicroelectronics Landing Team Lead
Linaro.org │ Open source software for ARM SoCs
Follow Linaro: Facebook | Twitter | Blog
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
