Commit 7086625f authored by Eddie James's avatar Eddie James Committed by Pavel Machek
Browse files

leds: pca955x: Add brightness_get function 



Add a function to fetch the state of the hardware LED.

Signed-off-by: default avatarEddie James <eajames@linux.ibm.com>
Signed-off-by: default avatarPavel Machek <pavel@ucw.cz>
parent 2420ae02

drivers/leds/leds-pca955x.c

+52 −0
Original line number Diff line number Diff line
@@ -233,6 +233,57 @@ static int pca955x_read_ls(struct i2c_client *client, int n, u8 *val) 
	return 0;

}



static int pca955x_read_pwm(struct i2c_client *client, int n, u8 *val)

{

	struct pca955x *pca955x = i2c_get_clientdata(client);

	u8 cmd = pca95xx_num_input_regs(pca955x->chipdef->bits) + 1 + (2 * n);

	int ret;



	ret = i2c_smbus_read_byte_data(client, cmd);

	if (ret < 0) {

		dev_err(&client->dev, "%s: reg 0x%x, err %d\n",

			__func__, n, ret);

		return ret;

	}

	*val = (u8)ret;

	return 0;

}



static enum led_brightness pca955x_led_get(struct led_classdev *led_cdev)

{

	struct pca955x_led *pca955x_led = container_of(led_cdev,

						       struct pca955x_led,

						       led_cdev);

	struct pca955x *pca955x = pca955x_led->pca955x;

	u8 ls, pwm;

	int ret;



	ret = pca955x_read_ls(pca955x->client, pca955x_led->led_num / 4, &ls);

	if (ret)

		return ret;



	ls = (ls >> ((pca955x_led->led_num % 4) << 1)) & 0x3;

	switch (ls) {

	case PCA955X_LS_LED_ON:

		ret = LED_FULL;

		break;

	case PCA955X_LS_LED_OFF:

		ret = LED_OFF;

		break;

	case PCA955X_LS_BLINK0:

		ret = LED_HALF;

		break;

	case PCA955X_LS_BLINK1:

		ret = pca955x_read_pwm(pca955x->client, 1, &pwm);

		if (ret)

			return ret;

		ret = 255 - pwm;

		break;

	}



	return ret;

}



static int pca955x_led_set(struct led_classdev *led_cdev,

			    enum led_brightness value)

{
@@ -512,6 +563,7 @@ static int pca955x_probe(struct i2c_client *client, 


			led->name = pca955x_led->name;

			led->brightness_set_blocking = pca955x_led_set;

			led->brightness_get = pca955x_led_get;



			err = devm_led_classdev_register(&client->dev, led);

			if (err)