[PATCHv2] leds: add regulator to lm3530 driver

[Shreshtha Kumar SAHU <shreshthakumar.sahu@stericsson.com>]

From: Shreshtha Kumar Sahu <shreshthakumar.sahu@stericsson.com>

This patch adds regulator support to lm3530 driver. lm3530 driver
need to get proper regulator during device probe and enable it
before accessing the device. Also it disables the regulator in
case of brightness == LED_OFF, and put back during driver remove.

Signed-off-by: Shreshtha Kumar Sahu <shreshthakumar.sahu@stericsson.com>
---
changes in v2:
  fixed checkpatch errors

 drivers/leds/leds-lm3530.c |   73 +++++++++++++++++++++++++++++++++++++++-----
 1 files changed, 65 insertions(+), 8 deletions(-)

diff --git a/drivers/leds/leds-lm3530.c b/drivers/leds/leds-lm3530.c
index b37e618..4d7ce76 100644
--- a/drivers/leds/leds-lm3530.c
+++ b/drivers/leds/leds-lm3530.c
@@ -17,6 +17,7 @@
 #include <linux/input.h>
 #include <linux/led-lm3530.h>
 #include <linux/types.h>
+#include <linux/regulator/consumer.h>
 
 #define LM3530_LED_DEV "lcd-backlight"
 #define LM3530_NAME "lm3530-led"
@@ -96,12 +97,18 @@ static struct lm3530_mode_map mode_map[] = {
  * @client: i2c client
  * @pdata: LM3530 platform data
  * @mode: mode of operation - manual, ALS, PWM
+ * @regulator: regulator
+ * @brighness: previous brightness value
+ * @enable: regulator is enabled
  */
 struct lm3530_data {
 	struct led_classdev led_dev;
 	struct i2c_client *client;
 	struct lm3530_platform_data *pdata;
 	enum lm3530_mode mode;
+	struct regulator *regulator;
+	enum led_brightness brightness;
+	bool enable;
 };
 
 static const u8 lm3530_reg[LM3530_REG_MAX] = {
@@ -172,7 +179,10 @@ static int lm3530_init_registers(struct lm3530_data *drvdata)
 	brt_ramp = (pltfm->brt_ramp_fall << LM3530_BRT_RAMP_FALL_SHIFT) |
 			(pltfm->brt_ramp_rise << LM3530_BRT_RAMP_RISE_SHIFT);
 
-	brightness = pltfm->brt_val;
+	if (drvdata->brightness)
+		brightness = drvdata->brightness;
+	else
+		brightness = drvdata->brightness = pltfm->brt_val;
 
 	reg_val[0] = gen_config;	/* LM3530_GEN_CONFIG */
 	reg_val[1] = als_config;	/* LM3530_ALS_CONFIG */
@@ -190,6 +200,16 @@ static int lm3530_init_registers(struct lm3530_data *drvdata)
 	reg_val[13] = LM3530_DEF_ZT_3;	/* LM3530_ALS_Z3T_REG */
 	reg_val[14] = LM3530_DEF_ZT_4;	/* LM3530_ALS_Z4T_REG */
 
+	if (!drvdata->enable) {
+		ret = regulator_enable(drvdata->regulator);
+		if (ret) {
+			dev_err(&drvdata->client->dev,
+					"Enable regulator failed\n");
+			return ret;
+		}
+		drvdata->enable = true;
+	}
+
 	for (i = 0; i < LM3530_REG_MAX; i++) {
 		ret = i2c_smbus_write_byte_data(client,
 				lm3530_reg[i], reg_val[i]);
@@ -210,12 +230,31 @@ static void lm3530_brightness_set(struct led_classdev *led_cdev,
 	switch (drvdata->mode) {
 	case LM3530_BL_MODE_MANUAL:
 
+		if (!drvdata->enable) {
+			err = lm3530_init_registers(drvdata);
+			if (err) {
+				dev_err(&drvdata->client->dev,
+					"Register Init failed: %d\n", err);
+				break;
+			}
+		}
+
 		/* set the brightness in brightness control register*/
 		err = i2c_smbus_write_byte_data(drvdata->client,
 				LM3530_BRT_CTRL_REG, brt_val / 2);
 		if (err)
 			dev_err(&drvdata->client->dev,
 				"Unable to set brightness: %d\n", err);
+		else
+			drvdata->brightness = brt_val / 2;
+
+		if (brt_val == 0) {
+			err = regulator_disable(drvdata->regulator);
+			if (err)
+				dev_err(&drvdata->client->dev,
+					"Disable regulator failed\n");
+			drvdata->enable = false;
+		}
 		break;
 	case LM3530_BL_MODE_ALS:
 		break;
@@ -297,20 +336,31 @@ static int __devinit lm3530_probe(struct i2c_client *client,
 	drvdata->mode = pdata->mode;
 	drvdata->client = client;
 	drvdata->pdata = pdata;
+	drvdata->brightness = LED_OFF;
+	drvdata->enable = false;
 	drvdata->led_dev.name = LM3530_LED_DEV;
 	drvdata->led_dev.brightness_set = lm3530_brightness_set;
 
 	i2c_set_clientdata(client, drvdata);
 
-	err = lm3530_init_registers(drvdata);
-	if (err < 0) {
-		dev_err(&client->dev, "Register Init failed: %d\n", err);
-		err = -ENODEV;
-		goto err_reg_init;
+	drvdata->regulator = regulator_get(&client->dev, "vin");
+	if (IS_ERR(drvdata->regulator)) {
+		dev_err(&client->dev, "regulator get failed\n");
+		err = PTR_ERR(drvdata->regulator);
+		drvdata->regulator = NULL;
+		goto err_regulator_get;
 	}
 
-	err = led_classdev_register((struct device *)
-				      &client->dev, &drvdata->led_dev);
+	if (drvdata->pdata->brt_val) {
+		err = lm3530_init_registers(drvdata);
+		if (err < 0) {
+			dev_err(&client->dev,
+				"Register Init failed: %d\n", err);
+			err = -ENODEV;
+			goto err_reg_init;
+		}
+	}
+	err = led_classdev_register(&client->dev, &drvdata->led_dev);
 	if (err < 0) {
 		dev_err(&client->dev, "Register led class failed: %d\n", err);
 		err = -ENODEV;
@@ -330,6 +380,9 @@ err_create_file:
 	led_classdev_unregister(&drvdata->led_dev);
 err_class_register:
 err_reg_init:
+	regulator_put(drvdata->regulator);
+err_regulator_get:
+	i2c_set_clientdata(client, NULL);
 	kfree(drvdata);
 err_out:
 	return err;
@@ -340,6 +393,10 @@ static int __devexit lm3530_remove(struct i2c_client *client)
 	struct lm3530_data *drvdata = i2c_get_clientdata(client);
 
 	device_remove_file(drvdata->led_dev.dev, &dev_attr_mode);
+
+	if (drvdata->enable)
+		regulator_disable(drvdata->regulator);
+	regulator_put(drvdata->regulator);
 	led_classdev_unregister(&drvdata->led_dev);
 	kfree(drvdata);
 	return 0;
-- 
1.7.2.dirty