Commit 3f467ebe authored by Nikolaus Voss's avatar Nikolaus Voss Committed by Thierry Reding
Browse files

leds: pwm: Support ACPI via firmware-node framework 



DT specific handling is replaced by firmware-node abstration to support
ACPI specification of PWM LEDS.

Example ASL:
Device (PWML)
{
    Name (_HID, "PRP0001")
    Name (_DSD, Package () {
          ToUUID("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"),
          Package () { Package () {"compatible",
                                    Package () {"pwm-leds"}}}})

    Device (PWL0)
    {
        Name (_HID, "PRP0001")
        Name (_DSD, Package () {
              ToUUID("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"),
              Package () {
                           Package () {"label", "alarm-led"},
                           Package () {"pwms", Package ()
                                       {\_SB_.PCI0.PWM, 0, 600000, 0}},
                           Package () {"linux,default-state", "off"}}})
    }
}

Signed-off-by: default avatarNikolaus Voss <nikolaus.voss@loewensteinmedical.de>
Acked-by: default avatarPavel Machek <pavel@ucw.cz>
Signed-off-by: default avatarThierry Reding <thierry.reding@gmail.com>
parent 4a6ef8e3

drivers/leds/leds-pwm.c

+27 −18
Original line number Diff line number Diff line
@@ -75,7 +75,7 @@ static inline size_t sizeof_pwm_leds_priv(int num_leds) 
}



static int led_pwm_add(struct device *dev, struct led_pwm_priv *priv,

		       struct led_pwm *led, struct device_node *child)

		       struct led_pwm *led, struct fwnode_handle *fwnode)

{

	struct led_pwm_data *led_data = &priv->leds[priv->num_leds];

	struct pwm_args pargs;
@@ -88,8 +88,8 @@ static int led_pwm_add(struct device *dev, struct led_pwm_priv *priv, 
	led_data->cdev.max_brightness = led->max_brightness;

	led_data->cdev.flags = LED_CORE_SUSPENDRESUME;



	if (child)

		led_data->pwm = devm_of_pwm_get(dev, child, NULL);

	if (fwnode)

		led_data->pwm = devm_fwnode_pwm_get(dev, fwnode, NULL);

	else

		led_data->pwm = devm_pwm_get(dev, led->name);

	if (IS_ERR(led_data->pwm)) {
@@ -114,7 +114,8 @@ static int led_pwm_add(struct device *dev, struct led_pwm_priv *priv, 
	if (!led_data->period && (led->pwm_period_ns > 0))

		led_data->period = led->pwm_period_ns;



	ret = devm_of_led_classdev_register(dev, child, &led_data->cdev);

	ret = devm_of_led_classdev_register(dev, to_of_node(fwnode),

					    &led_data->cdev);

	if (ret == 0) {

		priv->num_leds++;

		led_pwm_set(&led_data->cdev, led_data->cdev.brightness);
@@ -126,27 +127,35 @@ static int led_pwm_add(struct device *dev, struct led_pwm_priv *priv, 
	return ret;

}



static int led_pwm_create_of(struct device *dev, struct led_pwm_priv *priv)

static int led_pwm_create_fwnode(struct device *dev, struct led_pwm_priv *priv)

{

	struct device_node *child;

	struct fwnode_handle *fwnode;

	struct led_pwm led;

	int ret = 0;



	memset(&led, 0, sizeof(led));



	for_each_child_of_node(dev->of_node, child) {

		led.name = of_get_property(child, "label", NULL) ? :

			   child->name;

	device_for_each_child_node(dev, fwnode) {

		ret = fwnode_property_read_string(fwnode, "label", &led.name);

		if (ret && is_of_node(fwnode))

			led.name = to_of_node(fwnode)->name;



		led.default_trigger = of_get_property(child,

						"linux,default-trigger", NULL);

		led.active_low = of_property_read_bool(child, "active-low");

		of_property_read_u32(child, "max-brightness",

		if (!led.name) {

			fwnode_handle_put(fwnode);

			return -EINVAL;

		}



		fwnode_property_read_string(fwnode, "linux,default-trigger",

					    &led.default_trigger);



		led.active_low = fwnode_property_read_bool(fwnode,

							   "active-low");

		fwnode_property_read_u32(fwnode, "max-brightness",

					 &led.max_brightness);



		ret = led_pwm_add(dev, priv, &led, child);

		ret = led_pwm_add(dev, priv, &led, fwnode);

		if (ret) {

			of_node_put(child);

			fwnode_handle_put(fwnode);

			break;

		}

	}
@@ -164,7 +173,7 @@ static int led_pwm_probe(struct platform_device *pdev) 
	if (pdata)

		count = pdata->num_leds;

	else

		count = of_get_child_count(pdev->dev.of_node);

		count = device_get_child_node_count(&pdev->dev);



	if (!count)

		return -EINVAL;
@@ -182,7 +191,7 @@ static int led_pwm_probe(struct platform_device *pdev) 
				break;

		}

	} else {

		ret = led_pwm_create_of(&pdev->dev, priv);

		ret = led_pwm_create_fwnode(&pdev->dev, priv);

	}



	if (ret)

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