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-rw-r--r--Documentation/powerpc/dts-bindings/gpio/led.txt17
-rw-r--r--drivers/leds/leds-gpio.c20
-rw-r--r--include/linux/leds.h9
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;
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