[U-Boot] [PATCH 3/3] gpio_led: add support for inverted polarity

[Igor Grinberg]

On 11/08/13 01:03, Igor Grinberg wrote:
> Some GPIO connected LEDs have inverted polarity.
> Introduce new config option: CONFIG_GPIO_LED_INVERTED_TABLE for the
> specifying the inverted GPIO LEDs list and add support for this in the
> gpio_led driver.
> 
> Signed-off-by: Igor Grinberg <grinberg at compulab.co.il>

Tested-by: Ilya Ledvich <ilya at compulab.co.il>

on cm-t335.

> ---
>  README                  |  7 +++++++
>  drivers/misc/gpio_led.c | 27 +++++++++++++++++++++++++--
>  2 files changed, 32 insertions(+), 2 deletions(-)
> 
> diff --git a/README b/README
> index 55c71fa..b8bad51 100644
> --- a/README
> +++ b/README
> @@ -1959,6 +1959,13 @@ CBFS (Coreboot Filesystem) support
>  		status LED backend implementation. Define CONFIG_GPIO_LED
>  		to include the gpio_led driver in the U-Boot binary.
>  
> +		CONFIG_GPIO_LED_INVERTED_TABLE
> +		Some GPIO connected LEDs may have inverted polarity in which
> +		case the GPIO high value corresponds to LED off state and
> +		GPIO low value corresponds to LED on state.
> +		In such cases CONFIG_GPIO_LED_INVERTED_TABLE may be defined
> +		with a list of GPIO LEDs that have inverted polarity.
> +
>  - CAN Support:	CONFIG_CAN_DRIVER
>  
>  		Defining CONFIG_CAN_DRIVER enables CAN driver support
> diff --git a/drivers/misc/gpio_led.c b/drivers/misc/gpio_led.c
> index de20419..3e95727 100644
> --- a/drivers/misc/gpio_led.c
> +++ b/drivers/misc/gpio_led.c
> @@ -9,19 +9,42 @@
>  #include <status_led.h>
>  #include <asm/gpio.h>
>  
> +#ifndef CONFIG_GPIO_LED_INVERTED_TABLE
> +#define CONFIG_GPIO_LED_INVERTED_TABLE {}
> +#endif
> +
> +static led_id_t gpio_led_inv[] = CONFIG_GPIO_LED_INVERTED_TABLE;
> +
> +static int gpio_led_gpio_value(led_id_t mask, int state)
> +{
> +	int i, gpio_value = (state == STATUS_LED_ON);
> +
> +	for (i = 0; i < ARRAY_SIZE(gpio_led_inv); i++) {
> +		if (gpio_led_inv[i] == mask)
> +			gpio_value = !gpio_value;
> +	}
> +
> +	return gpio_value;
> +}
> +
>  void __led_init(led_id_t mask, int state)
>  {
> +	int gpio_value;
> +
>  	if (gpio_request(mask, "gpio_led") != 0) {
>  		printf("%s: failed requesting GPIO%lu!\n", __func__, mask);
>  		return;
>  	}
>  
> -	gpio_direction_output(mask, state == STATUS_LED_ON);
> +	gpio_value = gpio_led_gpio_value(mask, state);
> +	gpio_direction_output(mask, gpio_value);
>  }
>  
>  void __led_set(led_id_t mask, int state)
>  {
> -	gpio_set_value(mask, state == STATUS_LED_ON);
> +	int gpio_value = gpio_led_gpio_value(mask, state);
> +
> +	gpio_set_value(mask, gpio_value);
>  }
>  
>  void __led_toggle(led_id_t mask)
> 

-- 
Regards,
Igor.