From 9dfdcdfed4726f94fc38d94f29f8214f38058576 Mon Sep 17 00:00:00 2001 From: Igor Grinberg Date: Fri, 8 Nov 2013 01:03:52 +0200 Subject: [PATCH] gpio_led: add support for inverted polarity 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 Tested-by: Ilya Ledvich --- README | 7 +++++++ drivers/misc/gpio_led.c | 27 +++++++++++++++++++++++++-- 2 files changed, 32 insertions(+), 2 deletions(-) diff --git a/README b/README index 7b393b79b3..5def773ff5 100644 --- a/README +++ b/README @@ -1971,6 +1971,13 @@ 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 de2041956b..3e95727d79 100644 --- a/drivers/misc/gpio_led.c +++ b/drivers/misc/gpio_led.c @@ -9,19 +9,42 @@ #include #include +#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) -- 2.25.1