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 <grinberg@compulab.co.il>
Tested-by: Ilya Ledvich <ilya@compulab.co.il>
diff --git a/README b/README
index 7b393b7..5def773 100644
--- a/README
+++ b/README
@@ -1971,6 +1971,13 @@
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)