Hi Song, On 5.9.2018 04:34, Song Qiang wrote:
Some leds on our board are active low leds, which means these leds are lighted when the corresponding gpio line is low, while the original leds-gpio driver default all leds are active high leds. This patch adds a devicetree node "light-state", whose value should be "high" for active high leds and "low" for active low leds. The default value is "high" for compatible for the original driver.Signed-off-by: Song Qiang <songqiang.1304...@gmail.com> --- .../devicetree/bindings/leds/leds-gpio.txt | 15 +++++++++++ drivers/leds/leds-gpio.c | 25 +++++++++++++++++-- 2 files changed, 38 insertions(+), 2 deletions(-) diff --git a/Documentation/devicetree/bindings/leds/leds-gpio.txt b/Documentation/devicetree/bindings/leds/leds-gpio.txt index a48dda268f81..0a8fad75c704 100644 --- a/Documentation/devicetree/bindings/leds/leds-gpio.txt +++ b/Documentation/devicetree/bindings/leds/leds-gpio.txt @@ -23,6 +23,9 @@ LED sub-node properties: remains up. - panic-indicator : (optional) see Documentation/devicetree/bindings/leds/common.txt +- light-state: (optional) Values should be "high" or "low", which indicates + the state of the GPIO pin when the led is on. + see Documentation/devicetree/bindings/leds/common.txtExamples: @@ -64,3 +67,15 @@ leds {retain-state-suspended; }; }; + +leds { + compatible = "gpio-leds"; + + led0 { + label = "led0"; + gpios = <&gpio1 19 GPIO_ACTIVE_HIGH>;
With this patch you are introducing one more way to invert the logic. If your LED is active LOW, you should use GPIO_ACTIVE_LOW in your DT. All should work as expected then. Best regards, Michal
+ linux,default-trigger = "heartbeat"; + default-state = "off"; + light-state = "low"; + }; +} diff --git a/drivers/leds/leds-gpio.c b/drivers/leds/leds-gpio.c index 764c31301f90..463ded0c71ac 100644 --- a/drivers/leds/leds-gpio.c +++ b/drivers/leds/leds-gpio.c @@ -26,9 +26,13 @@ struct gpio_led_data { struct gpio_desc *gpiod; u8 can_sleep; u8 blinking; + u8 light_state; gpio_blink_set_t platform_gpio_blink_set; };+#define LEDS_GPIO_LIGHTSTATE_HIGH 0+#define LEDS_GPIO_LIGHTSTATE_LOW 1 + static inline struct gpio_led_data * cdev_to_gpio_led_data(struct led_classdev *led_cdev) { @@ -42,9 +46,15 @@ static void gpio_led_set(struct led_classdev *led_cdev, int level;if (value == LED_OFF)- level = 0; + if (led_dat->light_state == LEDS_GPIO_LIGHTSTATE_HIGH) + level = 0; + else + level = 1; else - level = 1; + if (led_dat->light_state == LEDS_GPIO_LIGHTSTATE_HIGH) + level = 1; + else + level = 0;if (led_dat->blinking) {led_dat->platform_gpio_blink_set(led_dat->gpiod, level, @@ -205,6 +215,17 @@ static struct gpio_leds_priv *gpio_leds_create(struct platform_device *pdev) led.default_state = LEDS_GPIO_DEFSTATE_OFF; }+ if (!fwnode_property_read_string(child, "light-state",+ &state)) { + if (!strcmp(state, "low")) + led_dat->light_state = + LEDS_GPIO_LIGHTSTATE_LOW; + else{ + led_dat->light_state = + LEDS_GPIO_LIGHTSTATE_HIGH; + } + } + if (fwnode_property_present(child, "retain-state-suspended")) led.retain_state_suspended = 1; if (fwnode_property_present(child, "retain-state-shutdown"))
