Re: [PATCH 2/2] leds: pwm: Add optional DT property default-brightness

Hello Lee

Thanks for the review!

On 10/31/24 17:32, Lee Jones wrote:

On Tue, 15 Oct 2024, George Stark wrote:

quoted

When probing if default LED state is on then default brightness will be
applied instead of max brightness.

Signed-off-by: George Stark <redacted>
---
  drivers/leds/leds-pwm.c | 13 ++++++++++---
  1 file changed, 10 insertions(+), 3 deletions(-)

diff --git a/drivers/leds/leds-pwm.c b/drivers/leds/leds-pwm.c
index 7961dca0db2f..514fc8ca3e80 100644
--- a/drivers/leds/leds-pwm.c
+++ b/drivers/leds/leds-pwm.c

@@ -65,7 +65,8 @@ static int led_pwm_set(struct led_classdev *led_cdev,
  
  __attribute__((nonnull))
  static int led_pwm_add(struct device *dev, struct led_pwm_priv *priv,
-		       struct led_pwm *led, struct fwnode_handle *fwnode)
+		       struct led_pwm *led, struct fwnode_handle *fwnode,
+		       unsigned int default_brightness)
  {
  	struct led_pwm_data *led_data = &priv->leds[priv->num_leds];
  	struct led_init_data init_data = { .fwnode = fwnode };

@@ -104,7 +105,7 @@ static int led_pwm_add(struct device *dev, struct led_pwm_priv *priv,
  	/* set brightness */
  	switch (led->default_state) {
  	case LEDS_DEFSTATE_ON:
-		led_data->cdev.brightness = led->max_brightness;
+		led_data->cdev.brightness = default_brightness;
  		break;
  	case LEDS_DEFSTATE_KEEP:
  		{

@@ -141,6 +142,7 @@ static int led_pwm_add(struct device *dev, struct led_pwm_priv *priv,
  static int led_pwm_create_fwnode(struct device *dev, struct led_pwm_priv *priv)
  {
  	struct led_pwm led;
+	unsigned int default_brightness;
  	int ret;
  
  	device_for_each_child_node_scoped(dev, fwnode) {

@@ -160,7 +162,12 @@ static int led_pwm_create_fwnode(struct device *dev, struct led_pwm_priv *priv)
  
  		led.default_state = led_init_default_state_get(fwnode);
  
-		ret = led_pwm_add(dev, priv, &led, fwnode);
+		ret = fwnode_property_read_u32(fwnode, "default-brightness",
+					       &default_brightness);
+		if (ret < 0 || default_brightness > led.max_brightness)
+			default_brightness = led.max_brightness;
+
+		ret = led_pwm_add(dev, priv, &led, fwnode, default_brightness);

This creates a lot more hopping around than is necessary.

Since led_pwm_add() already has access to the fwnode, why not look up
the property in there instead, thus massively simplifying things.

I looked up the new property here to be near to
led_init_default_state_get (both props are from the same group) and
led_pwm_add is big enough already. And you're absolutely right that the
patch can be optimized. Please take a look at the v2

quoted

  		if (ret)
  			return ret;
  	}
-- 
2.25.1

-- 
Best regards
George