u5500: leds: add ab5500v2 HVLED blink feature

This patch adds support for AB5500 v2.0 HVLED hardware blink feature
in existing driver.

ST-Ericsson Linux next: ER 336280
ST-Ericsson FOSS-OUT ID: Trivial
ST-Ericsson ID: ER 364964

Change-Id:I73e1caeac14774b7d3e03d1e7c5e4bd16fc7d06a
Signed-off-by: Shreshtha Kumar Sahu <shreshthakumar.sahu@stericsson.com>
Reviewed-on: http://gerrit.lud.stericsson.com/gerrit/27547
Reviewed-by: Srinidhi KASAGAR <srinidhi.kasagar@stericsson.com>
Reviewed-on: http://gerrit.lud.stericsson.com/gerrit/32746
Reviewed-by: Naga RADHESH Y <naga.radheshy@stericsson.com>
Tested-by: Naga RADHESH Y <naga.radheshy@stericsson.com>

3 files changed, 461 insertions, 72 deletions

diff --git a/arch/arm/mach-ux500/board-u5500.c b/arch/arm/mach-ux500/board-u5500.c
index 7a1715ea4aa..b2056bd28bb 100644
--- a/arch/arm/mach-ux500/board-u5500.c
+++ b/arch/arm/mach-ux500/board-u5500.c
@@ -108,24 +108,30 @@ static struct lm3530_platform_data u5500_als_platform_data = {
 
 /* leds-ab5500 */
 static struct ab5500_hvleds_platform_data ab5500_hvleds_data = {
-	.hw_blink = false,
+	.hw_fade = false,
 	.leds = {
 		[0] = {
 			.name = "red",
+			.led_on = true,
 			.led_id = 0,
-			.status = AB5500_LED_ON,
+			.fade_hi = 255,
+			.fade_lo = 0,
 			.max_current = 10, /* wrong value may damage h/w */
 		},
 		[1] = {
 			.name = "green",
+			.led_on = true,
 			.led_id = 1,
-			.status = AB5500_LED_ON,
+			.fade_hi = 255,
+			.fade_lo = 0,
 			.max_current = 10, /* wrong value may damage h/w */
 		},
 		[2] {
 			.name = "blue",
+			.led_on = true,
 			.led_id = 2,
-			.status = AB5500_LED_ON,
+			.fade_hi = 255,
+			.fade_lo = 0,
 			.max_current = 10, /* wrong value may damage h/w */
 		},
 	},
diff --git a/drivers/leds/leds-ab5500.c b/drivers/leds/leds-ab5500.c
index 94db3a6feea..294551b1962 100644
--- a/drivers/leds/leds-ab5500.c
+++ b/drivers/leds/leds-ab5500.c
@@ -1,13 +1,47 @@
 /*
+ * leds-ab5500.c - driver for High Voltage (HV) LED in ST-Ericsson AB5500 chip
+ *
  * Copyright (C) 2011 ST-Ericsson SA.
  *
  * License Terms: GNU General Public License v2
  *
- * Driver for LED in ST-Ericsson AB5500 v1.0 Analog baseband Controller
- *
  * Author: Shreshtha Kumar SAHU <shreshthakumar.sahu@stericsson.com>
  */
 
+/*
+ * Driver for HVLED in ST-Ericsson AB5500 analog baseband controller
+ *
+ * This chip can drive upto 3 leds, of upto 40mA of led sink current.
+ * These leds can be programmed to blink between two intensities with
+ * fading delay of half, one or two seconds.
+ *
+ * Leds can be controlled via sysfs entries in
+ *	"/sys/class/leds/< red | green | blue >"
+ *
+ * For each led,
+ *
+ * Modes of operation:
+ *  - manual:	echo 0 > fade_auto (default, no auto blinking)
+ *  - auto:	echo 1 > fade_auto
+ *
+ * Soft scaling delay between two intensities:
+ *  - 1/2 sec:	echo 1 > fade_delay
+ *  - 1 sec:	echo 2 > fade_delay
+ *  - 2 sec:	echo 3 > fade_delay
+ *
+ * Possible sequence of operation:
+ *  - continuous glow: set brightness (brt)
+ *  - blink between LED_OFF and LED_FULL:
+ *	set fade delay -> set fade auto
+ *  - blink between previous two brightness (only for LED-1):
+ *	set brt1 -> set brt2 -> set fade auto
+ *
+ * Delay can be set in any step, its affect will be seen on switching mode.
+ *
+ * Note: Blink/Fade feature is supported in AB5500 v2 onwards
+ *
+ */
+
 #include <linux/leds.h>
 #include <linux/slab.h>
 #include <linux/device.h>
@@ -18,45 +52,67 @@
 #include <linux/leds-ab5500.h>
 #include <linux/types.h>
 
+#include <mach/hardware.h>
+
 #define AB5500LED_NAME		"ab5500-leds"
+#define AB5500_LED_MAX		0x03
 
 /* Register offsets */
 #define AB5500_LED_REG_ENABLE	0x03
-#define AB5500_LED_FADE_CTL	0x0D
+#define AB5500_LED_FADE_CTRL	0x0D
 
-/* LED-0 */
+/* LED-0 Register Addr. Offsets */
 #define AB5500_LED0_PWM_DUTY	0x01
 #define AB5500_LED0_PWMFREQ	0x02
 #define AB5500_LED0_SINKCTL	0x0A
+#define AB5500_LED0_FADE_HI	0x11
+#define AB5500_LED0_FADE_LO	0x17
 
-/* LED-1 */
+/* LED-1 Register Addr. Offsets */
 #define AB5500_LED1_PWM_DUTY	0x05
 #define AB5500_LED1_PWMFREQ	0x06
 #define AB5500_LED1_SINKCTL	0x0B
+#define AB5500_LED1_FADE_HI	0x13
+#define AB5500_LED1_FADE_LO	0x19
 
-/* LED-2 */
+/* LED-2 Register Addr. Offsets */
 #define AB5500_LED2_PWM_DUTY	0x08
 #define AB5500_LED2_PWMFREQ	0x09
 #define AB5500_LED2_SINKCTL	0x0C
+#define AB5500_LED2_FADE_HI	0x15
+#define AB5500_LED2_FADE_LO	0x1B
+
+/* led-0/1/2 enable bit */
+#define AB5500_LED_ENABLE_MASK	0x04
 
-/* pwm duty cycle */
-#define AB5500_LED_PWMDUTY_OFF	0x0
-#define AB5500_LED_PWMDUTY_MAX	0x3FF
-#define AB5500_LED_PWMDUTY_STEP	(AB5500_LED_PWMDUTY_MAX/LED_FULL)
+/* led intensity */
+#define AB5500_LED_INTENSITY_OFF	0x0
+#define AB5500_LED_INTENSITY_MAX	0x3FF
+#define AB5500_LED_INTENSITY_STEP	(AB5500_LED_INTENSITY_MAX/LED_FULL)
 
 /* pwm frequency */
-#define AB5500_LED_PWMFREQ_MAX	0x0F	/* 373.39 @sysclk=26MHz */
+#define AB5500_LED_PWMFREQ_MAX		0x0F	/* 373.39 @sysclk=26MHz */
 #define AB5500_LED_PWMFREQ_SHIFT	4
 
 /* LED sink current control */
-#define AB5500_LED_SINKCURR_MAX	0x0F	/* 40mA */
+#define AB5500_LED_SINKCURR_MAX		0x0F	/* 40mA MAX */
 #define AB5500_LED_SINKCURR_SHIFT	4
 
+/* fade Control shift and masks */
+#define AB5500_FADE_DELAY_SHIFT		0x00
+#define AB5500_FADE_MODE_MASK		0x80
+#define AB5500_FADE_DELAY_MASK		0x03
+#define AB5500_FADE_START_MASK		0x04
+#define AB5500_FADE_ON_MASK		0x70
+#define AB5500_LED_FADE_ENABLE(ledid)	(0x40 >> (ledid))
+
 struct ab5500_led {
 	u8 id;
 	u8 max_current;
 	u16 brt_val;
-	enum ab5500_led_status status;
+	u16 fade_hi;
+	u16 fade_lo;
+	bool led_on;
 	struct led_classdev led_cdev;
 	struct work_struct led_work;
 };
@@ -66,26 +122,41 @@ struct ab5500_hvleds {
 	struct device *dev;
 	struct ab5500_hvleds_platform_data *pdata;
 	struct ab5500_led leds[AB5500_HVLEDS_MAX];
+	bool hw_fade;
+	bool fade_auto;
+	enum ab5500_fade_delay fade_delay;
 };
 
-static u8 ab5500_led_pwmduty_reg[] = {
+static u8 ab5500_led_pwmduty_reg[AB5500_LED_MAX] = {
 			AB5500_LED0_PWM_DUTY,
 			AB5500_LED1_PWM_DUTY,
 			AB5500_LED2_PWM_DUTY,
 };
 
-static u8 ab5500_led_pwmfreq_reg[] = {
+static u8 ab5500_led_pwmfreq_reg[AB5500_LED_MAX] = {
 			AB5500_LED0_PWMFREQ,
 			AB5500_LED1_PWMFREQ,
 			AB5500_LED2_PWMFREQ,
 };
 
-static u8 ab5500_led_sinkctl_reg[] = {
+static u8 ab5500_led_sinkctl_reg[AB5500_LED_MAX] = {
 			AB5500_LED0_SINKCTL,
 			AB5500_LED1_SINKCTL,
 			AB5500_LED2_SINKCTL
 };
 
+static u8 ab5500_led_fade_hi_reg[AB5500_LED_MAX] = {
+			AB5500_LED0_FADE_HI,
+			AB5500_LED1_FADE_HI,
+			AB5500_LED2_FADE_HI,
+};
+
+static u8 ab5500_led_fade_lo_reg[AB5500_LED_MAX] = {
+			AB5500_LED0_FADE_LO,
+			AB5500_LED1_FADE_LO,
+			AB5500_LED2_FADE_LO,
+};
+
 #define to_led(_x)	container_of(_x, struct ab5500_led, _x)
 
 static inline struct ab5500_hvleds *led_to_hvleds(struct ab5500_led *led)
@@ -93,19 +164,74 @@ static inline struct ab5500_hvleds *led_to_hvleds(struct ab5500_led *led)
 	return container_of(led, struct ab5500_hvleds, leds[led->id]);
 }
 
+static int ab5500_led_enable(struct ab5500_hvleds *hvleds,
+		unsigned int led_id)
+{
+	int ret;
+
+	ret = abx500_mask_and_set_register_interruptible(
+			hvleds->dev, AB5500_BANK_LED,
+			ab5500_led_pwmduty_reg[led_id],
+			AB5500_LED_ENABLE_MASK,
+			AB5500_LED_ENABLE_MASK);
+	if (ret < 0)
+		dev_err(hvleds->dev, "reg[%d] w failed: %d\n",
+				ab5500_led_pwmduty_reg[led_id], ret);
+
+	return ret;
+
+}
+
+static int ab5500_led_start_manual(struct ab5500_hvleds *hvleds)
+{
+	int ret;
+
+	mutex_lock(&hvleds->lock);
+
+	ret = abx500_mask_and_set_register_interruptible(
+			hvleds->dev, AB5500_BANK_LED,
+			AB5500_LED_FADE_CTRL, AB5500_FADE_START_MASK,
+			AB5500_FADE_START_MASK);
+	if (ret < 0)
+		dev_err(hvleds->dev, "update reg 0x%x failed - %d\n",
+				AB5500_LED_FADE_CTRL, ret);
+
+	mutex_unlock(&hvleds->lock);
+
+	return ret;
+}
+
+static int ab5500_led_disable(struct ab5500_hvleds *hvleds,
+		unsigned int led_id)
+{
+	int ret;
+
+	ret = abx500_set_register_interruptible(
+			hvleds->dev, AB5500_BANK_LED,
+			ab5500_led_pwmduty_reg[led_id] - 1, 0);
+	ret |= abx500_set_register_interruptible(
+			hvleds->dev, AB5500_BANK_LED,
+			ab5500_led_pwmduty_reg[led_id], 0);
+	if (ret < 0)
+		dev_err(hvleds->dev, "reg[%d] w failed: %d\n",
+			ab5500_led_pwmduty_reg[led_id], ret);
+
+	return ret;
+}
+
 static int ab5500_led_pwmduty_write(struct ab5500_hvleds *hvleds,
 			unsigned int led_id, u16 val)
 {
 	int ret;
-	int val_lsb = val & 0xFF;
-	int val_msb = (val & 0x300) >> 8;
+	u8 val_lsb = val & 0xFF;
+	u8 val_msb = (val & 0x300) >> 8;
 
 	mutex_lock(&hvleds->lock);
 
 	dev_dbg(hvleds->dev, "ab5500-leds: reg[%d] w val = %d\n"
-		 "reg[%d] w val = %d\n",
-		 ab5500_led_pwmduty_reg[led_id] - 1, val_lsb,
-		 ab5500_led_pwmduty_reg[led_id], val_msb);
+		"reg[%d] w val = %d\n",
+		ab5500_led_pwmduty_reg[led_id] - 1, val_lsb,
+		ab5500_led_pwmduty_reg[led_id], val_msb);
 
 	ret = abx500_set_register_interruptible(
 			hvleds->dev, AB5500_BANK_LED,
@@ -116,6 +242,7 @@ static int ab5500_led_pwmduty_write(struct ab5500_hvleds *hvleds,
 	if (ret < 0)
 		dev_err(hvleds->dev, "reg[%d] w failed: %d\n",
 			ab5500_led_pwmduty_reg[led_id], ret);
+
 	mutex_unlock(&hvleds->lock);
 
 	return ret;
@@ -139,6 +266,7 @@ static int ab5500_led_pwmfreq_write(struct ab5500_hvleds *hvleds,
 	if (ret < 0)
 		dev_err(hvleds->dev, "reg[%d] w failed: %d\n",
 			ab5500_led_pwmfreq_reg[led_id], ret);
+
 	mutex_unlock(&hvleds->lock);
 
 	return ret;
@@ -149,19 +277,58 @@ static int ab5500_led_sinkctl_write(struct ab5500_hvleds *hvleds,
 {
 	int ret;
 
-	val = (val & 0x0F) << AB5500_LED_SINKCURR_SHIFT;
+	if (val > AB5500_LED_SINKCURR_MAX)
+		val = AB5500_LED_SINKCURR_MAX;
 
-	mutex_lock(&hvleds->lock);
+	val = (val << AB5500_LED_SINKCURR_SHIFT);
 
 	dev_dbg(hvleds->dev, "ab5500-leds: reg[%d] w val=%d\n",
 			ab5500_led_sinkctl_reg[led_id], val);
 
+	mutex_lock(&hvleds->lock);
+
 	ret = abx500_set_register_interruptible(
 			hvleds->dev, AB5500_BANK_LED,
 			ab5500_led_sinkctl_reg[led_id], val);
 	if (ret < 0)
 		dev_err(hvleds->dev, "reg[%d] w failed: %d\n",
 			ab5500_led_sinkctl_reg[led_id], ret);
+
+	mutex_unlock(&hvleds->lock);
+
+	return ret;
+}
+
+static int ab5500_led_fade_write(struct ab5500_hvleds *hvleds,
+			unsigned int led_id, bool on, u16 val)
+{
+	int ret;
+	int val_lsb = val & 0xFF;
+	int val_msb = (val & 0x300) >> 8;
+	u8 *fade_reg;
+
+	if (on)
+		fade_reg = ab5500_led_fade_hi_reg;
+	else
+		fade_reg = ab5500_led_fade_lo_reg;
+
+	dev_dbg(hvleds->dev, "ab5500-leds: reg[%d] w val = %d\n"
+		"reg[%d] w val = %d\n",
+		fade_reg[led_id] - 1, val_lsb,
+		fade_reg[led_id], val_msb);
+
+	mutex_lock(&hvleds->lock);
+
+	ret = abx500_set_register_interruptible(
+			hvleds->dev, AB5500_BANK_LED,
+			fade_reg[led_id] - 1, val_lsb);
+	ret |= abx500_set_register_interruptible(
+			hvleds->dev, AB5500_BANK_LED,
+			fade_reg[led_id], val_msb);
+	if (ret < 0)
+		dev_err(hvleds->dev, "reg[%d] w failed: %d\n",
+			fade_reg[led_id], ret);
+
 	mutex_unlock(&hvleds->lock);
 
 	return ret;
@@ -174,6 +341,7 @@ static int ab5500_led_sinkctl_read(struct ab5500_hvleds *hvleds,
 	u8 val;
 
 	mutex_lock(&hvleds->lock);
+
 	ret = abx500_get_register_interruptible(
 			hvleds->dev, AB5500_BANK_LED,
 			ab5500_led_sinkctl_reg[led_id], &val);
@@ -183,7 +351,9 @@ static int ab5500_led_sinkctl_read(struct ab5500_hvleds *hvleds,
 		mutex_unlock(&hvleds->lock);
 		return ret;
 	}
+
 	val = (val & 0xF0) >> AB5500_LED_SINKCURR_SHIFT;
+
 	mutex_unlock(&hvleds->lock);
 
 	return val;
@@ -196,7 +366,8 @@ static void ab5500_led_brightness_set(struct led_classdev *led_cdev,
 
 	/* adjust LED_FULL to 10bit range */
 	brt_val &= LED_FULL;
-	led->brt_val = brt_val * AB5500_LED_PWMDUTY_STEP;
+	led->brt_val = brt_val * AB5500_LED_INTENSITY_STEP;
+
 	schedule_work(&led->led_work);
 }
 
@@ -205,8 +376,13 @@ static void ab5500_led_work(struct work_struct *led_work)
 	struct ab5500_led *led = to_led(led_work);
 	struct ab5500_hvleds *hvleds = led_to_hvleds(led);
 
-	if (led->status == AB5500_LED_ON)
+	if (led->led_on == true) {
 		ab5500_led_pwmduty_write(hvleds, led->id, led->brt_val);
+		if (hvleds->hw_fade && led->brt_val) {
+			ab5500_led_enable(hvleds, led->id);
+			ab5500_led_start_manual(hvleds);
+		}
+	}
 }
 
 static ssize_t ab5500_led_show_current(struct device *dev,
@@ -248,9 +424,122 @@ static ssize_t ab5500_led_store_current(struct device *dev,
 	return len;
 }
 
+static ssize_t ab5500_led_store_fade_auto(struct device *dev,
+			struct device_attribute *attr,
+			const char *buf, size_t len)
+{
+	int ret;
+	u8 fade_ctrl = 0;
+	unsigned long fade_auto;
+	struct led_classdev *led_cdev = dev_get_drvdata(dev);
+	struct ab5500_led *led = to_led(led_cdev);
+	struct ab5500_hvleds *hvleds = led_to_hvleds(led);
+
+	if (strict_strtoul(buf, 0, &fade_auto))
+		return -EINVAL;
+
+	if (fade_auto > 1) {
+		dev_err(hvleds->dev, "invalid mode\n");
+		return -EINVAL;
+	}
+
+	mutex_lock(&hvleds->lock);
+
+	ret = abx500_get_register_interruptible(
+			hvleds->dev, AB5500_BANK_LED,
+			AB5500_LED_FADE_CTRL, &fade_ctrl);
+	if (ret < 0) {
+		dev_err(hvleds->dev, "reg[%d] w failed: %d\n",
+				AB5500_LED_FADE_CTRL, ret);
+		goto unlock_and_return;
+	}
+
+	/* manual mode */
+	if (fade_auto == false) {
+		fade_ctrl &= ~(AB5500_LED_FADE_ENABLE(led->id));
+		if (!(fade_ctrl & AB5500_FADE_ON_MASK))
+			fade_ctrl = 0;
+
+		ret = ab5500_led_disable(hvleds, led->id);
+		if (ret < 0)
+			goto unlock_and_return;
+	} else {
+		/* set led auto enable bit */
+		fade_ctrl |= AB5500_FADE_MODE_MASK;
+		fade_ctrl |= AB5500_LED_FADE_ENABLE(led->id);
+
+		/* set fade delay */
+		fade_ctrl &= ~AB5500_FADE_DELAY_MASK;
+		fade_ctrl |= hvleds->fade_delay << AB5500_FADE_DELAY_SHIFT;
+
+		/* set fade start manual */
+		fade_ctrl |= AB5500_FADE_START_MASK;
+
+		/* enble corresponding led */
+		ret = ab5500_led_enable(hvleds, led->id);
+		if (ret < 0)
+			goto unlock_and_return;
+
+	}
+
+	ret = abx500_set_register_interruptible(
+				hvleds->dev, AB5500_BANK_LED,
+				AB5500_LED_FADE_CTRL, fade_ctrl);
+	if (ret < 0) {
+		dev_err(hvleds->dev, "reg[%d] w failed: %d\n",
+			       AB5500_LED_FADE_CTRL, ret);
+		goto unlock_and_return;
+	}
+
+	hvleds->fade_auto = fade_auto;
+
+	ret = len;
+
+unlock_and_return:
+	mutex_unlock(&hvleds->lock);
+
+	return ret;
+}
+
+static ssize_t ab5500_led_show_fade_auto(struct device *dev,
+			struct device_attribute *attr, char *buf)
+{
+	struct led_classdev *led_cdev = dev_get_drvdata(dev);
+	struct ab5500_led *led = to_led(led_cdev);
+	struct ab5500_hvleds *hvleds = led_to_hvleds(led);
+
+	return sprintf(buf, "%d\n", hvleds->fade_auto);
+}
+
+static ssize_t ab5500_led_store_fade_delay(struct device *dev,
+			struct device_attribute *attr,
+			const char *buf, size_t len)
+{
+	unsigned long fade_delay;
+	struct led_classdev *led_cdev = dev_get_drvdata(dev);
+	struct ab5500_led *led = to_led(led_cdev);
+	struct ab5500_hvleds *hvleds = led_to_hvleds(led);
+
+	if (strict_strtoul(buf, 0, &fade_delay))
+		return -EINVAL;
+
+	if (fade_delay > AB5500_FADE_DELAY_TWOSEC) {
+		dev_err(hvleds->dev, "invalid mode\n");
+		return -EINVAL;
+	}
+
+	hvleds->fade_delay = fade_delay;
+
+	return len;
+}
+
 /* led class device attributes */
 static DEVICE_ATTR(led_current, S_IRUGO | S_IWUGO,
 	       ab5500_led_show_current, ab5500_led_store_current);
+static DEVICE_ATTR(fade_auto, S_IRUGO | S_IWUGO,
+	       ab5500_led_show_fade_auto, ab5500_led_store_fade_auto);
+static DEVICE_ATTR(fade_delay, S_IRUGO | S_IWUGO,
+	       NULL, ab5500_led_store_fade_delay);
 
 static int ab5500_led_init_registers(struct ab5500_hvleds *hvleds)
 {
@@ -258,30 +547,52 @@ static int ab5500_led_init_registers(struct ab5500_hvleds *hvleds)
 	unsigned int led_id;
 
 	/*  fade - manual : dur mid : pwm duty mid */
-	ret = abx500_set_register_interruptible(
+	if (!hvleds->hw_fade) {
+		ret = abx500_set_register_interruptible(
 				hvleds->dev, AB5500_BANK_LED,
 				AB5500_LED_REG_ENABLE, true);
-	if (ret < 0) {
-		dev_err(hvleds->dev, "reg[%d] w failed: %d\n",
-			       AB5500_LED_REG_ENABLE,	ret);
-		return ret;
+		if (ret < 0) {
+			dev_err(hvleds->dev, "reg[%d] w failed: %d\n",
+					AB5500_LED_REG_ENABLE, ret);
+			return ret;
+		}
 	}
 
 	for (led_id = 0; led_id < AB5500_HVLEDS_MAX; led_id++) {
-		/* Set pwm freq. and sink current to mid values */
-		ret = ab5500_led_pwmfreq_write(
-				hvleds, led_id, AB5500_LED_PWMFREQ_MAX);
-		if (ret < 0)
-			return ret;
+		if (hvleds->leds[led_id].led_on == false)
+			continue;
 
 		ret = ab5500_led_sinkctl_write(
-				hvleds, led_id, AB5500_LED_SINKCURR_MAX);
+				hvleds, led_id,
+				hvleds->leds[led_id].max_current);
 		if (ret < 0)
 			return ret;
 
+		if (hvleds->hw_fade) {
+			ret = ab5500_led_pwmfreq_write(
+					hvleds, led_id,
+					AB5500_LED_PWMFREQ_MAX / 2);
+			if (ret < 0)
+				return ret;
+
+			/* fade high intensity */
+			ret = ab5500_led_fade_write(
+					hvleds, led_id, true,
+					hvleds->leds[led_id].fade_hi);
+			if (ret < 0)
+				return ret;
+
+			/* fade low intensity */
+			ret = ab5500_led_fade_write(
+					hvleds, led_id, false,
+					hvleds->leds[led_id].fade_lo);
+			if (ret < 0)
+				return ret;
+		}
+
 		/* init led off */
-		ret = ab5500_led_pwmduty_write(
-				hvleds, led_id, AB5500_LED_PWMDUTY_OFF);
+		ret |= ab5500_led_pwmduty_write(
+				hvleds, led_id, AB5500_LED_INTENSITY_OFF);
 		if (ret < 0)
 			return ret;
 	}
@@ -294,12 +605,18 @@ static int ab5500_led_register_leds(struct device *dev,
 			struct ab5500_hvleds *hvleds)
 {
 	int i_led;
-	int err;
+	int ret = 0;
 	struct ab5500_led_conf *pled;
 	struct ab5500_led *led;
 
 	hvleds->dev = dev;
 	hvleds->pdata = pdata;
+
+	if (abx500_get_chip_id(dev) == AB5500_2_0)
+		hvleds->hw_fade = true;
+	else
+		hvleds->hw_fade = false;
+
 	for (i_led = 0; i_led < AB5500_HVLEDS_MAX; i_led++) {
 		pled = &pdata->leds[i_led];
 		led = &hvleds->leds[i_led];
@@ -308,84 +625,137 @@ static int ab5500_led_register_leds(struct device *dev,
 
 		led->id = pled->led_id;
 		led->max_current = pled->max_current;
-		led->status = pled->status;
+		led->led_on = pled->led_on;
 		led->led_cdev.name = pled->name;
 		led->led_cdev.brightness_set = ab5500_led_brightness_set;
 
-		err = led_classdev_register(dev, &led->led_cdev);
-		if (err < 0) {
-			dev_err(dev, "Register led class failed: %d\n", err);
+		/* Provide interface only for enabled LEDs */
+		if (led->led_on == false)
+			continue;
+
+		if (hvleds->hw_fade) {
+			led->fade_hi = (pled->fade_hi & LED_FULL);
+			led->fade_hi *= AB5500_LED_INTENSITY_STEP;
+			led->fade_lo = (pled->fade_lo & LED_FULL);
+			led->fade_lo *= AB5500_LED_INTENSITY_STEP;
+		}
+
+		ret = led_classdev_register(dev, &led->led_cdev);
+		if (ret < 0) {
+			dev_err(dev, "Register led class failed: %d\n", ret);
 			goto bailout1;
 		}
 
-		err = device_create_file(led->led_cdev.dev,
+		ret = device_create_file(led->led_cdev.dev,
 						&dev_attr_led_current);
-		if (err < 0) {
-			dev_err(dev, "sysfs device creation failed: %d\n", err);
+		if (ret < 0) {
+			dev_err(dev, "sysfs device creation failed: %d\n", ret);
 			goto bailout2;
 		}
+
+		if (hvleds->hw_fade) {
+			ret = device_create_file(led->led_cdev.dev,
+					&dev_attr_fade_auto);
+			if (ret < 0) {
+				dev_err(dev, "sysfs device "
+					"creation failed: %d\n", ret);
+				goto bailout3;
+			}
+
+			ret = device_create_file(led->led_cdev.dev,
+					&dev_attr_fade_delay);
+			if (ret < 0) {
+				dev_err(dev, "sysfs device "
+					"creation failed: %d\n", ret);
+				goto bailout4;
+			}
+		}
 	}
 
-	return err;
+	return ret;
 	for (; i_led >= 0; i_led--) {
-		device_remove_file(led->led_cdev.dev, &dev_attr_led_current);
+		if (hvleds->leds[i_led].led_on == false)
+			continue;
+
+		if (hvleds->hw_fade) {
+			device_remove_file(hvleds->leds[i_led].led_cdev.dev,
+					&dev_attr_fade_delay);
+bailout4:
+			device_remove_file(hvleds->leds[i_led].led_cdev.dev,
+					&dev_attr_fade_auto);
+		}
+bailout3:
+		device_remove_file(hvleds->leds[i_led].led_cdev.dev,
+				&dev_attr_led_current);
 bailout2:
 		led_classdev_unregister(&hvleds->leds[i_led].led_cdev);
 bailout1:
 		cancel_work_sync(&hvleds->leds[i_led].led_work);
 	}
-	return err;
+	return ret;
 }
 
 static int __devinit ab5500_hvleds_probe(struct platform_device *pdev)
 {
 	struct ab5500_hvleds_platform_data *pdata = pdev->dev.platform_data;
 	struct ab5500_hvleds *hvleds = NULL;
-	int err = 0, i;
+	int ret = 0, i;
 
 	if (pdata == NULL) {
 		dev_err(&pdev->dev, "platform data required\n");
-		err = -ENODEV;
+		ret = -ENODEV;
 		goto err_out;
 	}
 
 	hvleds = kzalloc(sizeof(struct ab5500_hvleds), GFP_KERNEL);
 	if (hvleds == NULL) {
-		err = -ENOMEM;
+		ret = -ENOMEM;
 		goto err_out;
 	}
 
 	mutex_init(&hvleds->lock);
 
 	/* init leds data and register led_classdev */
-	err = ab5500_led_register_leds(&pdev->dev, pdata, hvleds);
-	if (err < 0) {
-		dev_err(&pdev->dev, "leds registeration failed\n");
+	ret = ab5500_led_register_leds(&pdev->dev, pdata, hvleds);
+	if (ret < 0) {
+		dev_err(&pdev->dev, "leds registration failed\n");
 		goto err_out;
 	}
 
 	/* init device registers and set initial led current */
-	err = ab5500_led_init_registers(hvleds);
-	if (err < 0) {
-		dev_err(&pdev->dev, "reg init failed: %d\n", err);
+	ret = ab5500_led_init_registers(hvleds);
+	if (ret < 0) {
+		dev_err(&pdev->dev, "reg init failed: %d\n", ret);
 		goto err_reg_init;
 	}
 
-	dev_info(&pdev->dev, "enabled\n");
+	if (hvleds->hw_fade)
+		dev_info(&pdev->dev, "v2 enabled\n");
+	else
+		dev_info(&pdev->dev, "v1 enabled\n");
 
-	return err;
+	return ret;
 
 err_reg_init:
 	for (i = 0; i < AB5500_HVLEDS_MAX; i++) {
 		struct ab5500_led *led = &hvleds->leds[i];
 
-		led_classdev_unregister(&led->led_cdev);
+		if (led->led_on == false)
+			continue;
+
 		device_remove_file(led->led_cdev.dev, &dev_attr_led_current);
+		if (hvleds->hw_fade) {
+			device_remove_file(led->led_cdev.dev,
+					&dev_attr_fade_auto);
+			device_remove_file(led->led_cdev.dev,
+					&dev_attr_fade_delay);
+		}
+		led_classdev_unregister(&led->led_cdev);
 		cancel_work_sync(&led->led_work);
 	}
 err_out:
 	kfree(hvleds);
-	return err;
+	return ret;
 }
 
 static int __devexit ab5500_hvleds_remove(struct platform_device *pdev)
@@ -396,8 +766,17 @@ static int __devexit ab5500_hvleds_remove(struct platform_device *pdev)
 	for (i = 0; i < AB5500_HVLEDS_MAX; i++) {
 		struct ab5500_led *led = &hvleds->leds[i];
 
-		led_classdev_unregister(&led->led_cdev);
+		if (led->led_on == false)
+			continue;
+
 		device_remove_file(led->led_cdev.dev, &dev_attr_led_current);
+		if (hvleds->hw_fade) {
+			device_remove_file(led->led_cdev.dev,
+					&dev_attr_fade_auto);
+			device_remove_file(led->led_cdev.dev,
+					&dev_attr_fade_delay);
+		}
+		led_classdev_unregister(&led->led_cdev);
 		cancel_work_sync(&led->led_work);
 	}
 	kfree(hvleds);
diff --git a/include/linux/leds-ab5500.h b/include/linux/leds-ab5500.h
index 2db6ffd188e..9ba9ac61d90 100644
--- a/include/linux/leds-ab5500.h
+++ b/include/linux/leds-ab5500.h
@@ -13,19 +13,23 @@
 #define AB5500_HVLED2		2
 #define AB5500_HVLEDS_MAX	3
 
-enum ab5500_led_status {
-	AB5500_LED_OFF = 0x00,
-	AB5500_LED_ON,
+enum ab5500_fade_delay {
+	AB5500_FADE_DELAY_BYPASS = 0,
+	AB5500_FADE_DELAY_HALFSEC,
+	AB5500_FADE_DELAY_ONESEC,
+	AB5500_FADE_DELAY_TWOSEC
 };
 
 struct ab5500_led_conf {
 	char *name;
 	u8 led_id;
-	enum ab5500_led_status status;
 	u8 max_current;
+	u8 fade_hi;
+	u8 fade_lo;
+	bool led_on;
 };
 
 struct ab5500_hvleds_platform_data {
-	bool hw_blink;
+	bool hw_fade;
 	struct ab5500_led_conf leds[AB5500_HVLEDS_MAX];
 };