diff options
| -rw-r--r-- | Documentation/powerpc/dts-bindings/gpio/led.txt | 17 | ||||
| -rw-r--r-- | drivers/leds/leds-gpio.c | 20 | ||||
| -rw-r--r-- | include/linux/leds.h | 9 |
3 files changed, 40 insertions, 6 deletions
diff --git a/Documentation/powerpc/dts-bindings/gpio/led.txt b/Documentation/powerpc/dts-bindings/gpio/led.txt index 4fe14de..064db92 100644 --- a/Documentation/powerpc/dts-bindings/gpio/led.txt +++ b/Documentation/powerpc/dts-bindings/gpio/led.txt @@ -16,10 +16,17 @@ LED sub-node properties: string defining the trigger assigned to the LED. Current triggers are: "backlight" - LED will act as a back-light, controlled by the framebuffer system - "default-on" - LED will turn on + "default-on" - LED will turn on, but see "default-state" below "heartbeat" - LED "double" flashes at a load average based rate "ide-disk" - LED indicates disk activity "timer" - LED flashes at a fixed, configurable rate +- default-state: (optional) The initial state of the LED. Valid + values are "on", "off", and "keep". If the LED is already on or off + and the default-state property is set the to same value, then no + glitch should be produced where the LED momentarily turns off (or + on). The "keep" setting will keep the LED at whatever its current + state is, without producing a glitch. The default is off if this + property is not present. Examples: @@ -30,14 +37,22 @@ leds { gpios = <&mcu_pio 0 1>; /* Active low */ linux,default-trigger = "ide-disk"; }; + + fault { + gpios = <&mcu_pio 1 0>; + /* Keep LED on if BIOS detected hardware fault */ + default-state = "keep"; + }; }; run-control { compatible = "gpio-leds"; red { gpios = <&mpc8572 6 0>; + default-state = "off"; }; green { gpios = <&mpc8572 7 0>; + default-state = "on"; }; } diff --git a/drivers/leds/leds-gpio.c b/drivers/leds/leds-gpio.c index 76895e6..6b06638 100644 --- a/drivers/leds/leds-gpio.c +++ b/drivers/leds/leds-gpio.c @@ -76,7 +76,7 @@ static int __devinit create_gpio_led(const struct gpio_led *template, struct gpio_led_data *led_dat, struct device *parent, int (*blink_set)(unsigned, unsigned long *, unsigned long *)) { - int ret; + int ret, state; /* skip leds that aren't available */ if (!gpio_is_valid(template->gpio)) { @@ -99,11 +99,15 @@ static int __devinit create_gpio_led(const struct gpio_led *template, led_dat->cdev.blink_set = gpio_blink_set; } led_dat->cdev.brightness_set = gpio_led_set; - led_dat->cdev.brightness = LED_OFF; + if (template->default_state == LEDS_GPIO_DEFSTATE_KEEP) + state = !!gpio_get_value(led_dat->gpio) ^ led_dat->active_low; + else + state = (template->default_state == LEDS_GPIO_DEFSTATE_ON); + led_dat->cdev.brightness = state ? LED_FULL : LED_OFF; if (!template->retain_state_suspended) led_dat->cdev.flags |= LED_CORE_SUSPENDRESUME; - ret = gpio_direction_output(led_dat->gpio, led_dat->active_low); + ret = gpio_direction_output(led_dat->gpio, led_dat->active_low ^ state); if (ret < 0) goto err; @@ -223,12 +227,22 @@ static int __devinit of_gpio_leds_probe(struct of_device *ofdev, memset(&led, 0, sizeof(led)); for_each_child_of_node(np, child) { enum of_gpio_flags flags; + const char *state; led.gpio = of_get_gpio_flags(child, 0, &flags); led.active_low = flags & OF_GPIO_ACTIVE_LOW; led.name = of_get_property(child, "label", NULL) ? : child->name; led.default_trigger = of_get_property(child, "linux,default-trigger", NULL); + state = of_get_property(child, "default-state", NULL); + if (state) { + if (!strcmp(state, "keep")) + led.default_state = LEDS_GPIO_DEFSTATE_KEEP; + else if(!strcmp(state, "on")) + led.default_state = LEDS_GPIO_DEFSTATE_ON; + else + led.default_state = LEDS_GPIO_DEFSTATE_OFF; + } ret = create_gpio_led(&led, &pdata->led_data[pdata->num_leds++], &ofdev->dev, NULL); diff --git a/include/linux/leds.h b/include/linux/leds.h index c7f0b14..62af629 100644 --- a/include/linux/leds.h +++ b/include/linux/leds.h @@ -143,9 +143,14 @@ struct gpio_led { const char *name; const char *default_trigger; unsigned gpio; - u8 active_low : 1; - u8 retain_state_suspended : 1; + unsigned active_low : 1; + unsigned retain_state_suspended : 1; + unsigned default_state : 2; + /* default_state should be one of LEDS_GPIO_DEFSTATE_(ON|OFF|KEEP) */ }; +#define LEDS_GPIO_DEFSTATE_OFF 0 +#define LEDS_GPIO_DEFSTATE_ON 1 +#define LEDS_GPIO_DEFSTATE_KEEP 2 struct gpio_led_platform_data { int num_leds; |