1 files changed, 501 insertions, 0 deletions

diff --git a/drivers/leds/leds-lm3530.c b/drivers/leds/leds-lm3530.c
new file mode 100644
index 000000000..2f8362f6b
--- /dev/null
+++ b/drivers/leds/leds-lm3530.c
@@ -0,0 +1,501 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2011 ST-Ericsson SA.
+ * Copyright (C) 2009 Motorola, Inc.
+ *
+ * Simple driver for National Semiconductor LM3530 Backlight driver chip
+ *
+ * Author: Shreshtha Kumar SAHU <shreshthakumar.sahu@stericsson.com>
+ * based on leds-lm3530.c by Dan Murphy <D.Murphy@motorola.com>
+ */
+
+#include <linux/i2c.h>
+#include <linux/leds.h>
+#include <linux/slab.h>
+#include <linux/platform_device.h>
+#include <linux/input.h>
+#include <linux/led-lm3530.h>
+#include <linux/types.h>
+#include <linux/regulator/consumer.h>
+#include <linux/module.h>
+
+#define LM3530_LED_DEV "lcd-backlight"
+#define LM3530_NAME "lm3530-led"
+
+#define LM3530_GEN_CONFIG		0x10
+#define LM3530_ALS_CONFIG		0x20
+#define LM3530_BRT_RAMP_RATE		0x30
+#define LM3530_ALS_IMP_SELECT		0x41
+#define LM3530_BRT_CTRL_REG		0xA0
+#define LM3530_ALS_ZB0_REG		0x60
+#define LM3530_ALS_ZB1_REG		0x61
+#define LM3530_ALS_ZB2_REG		0x62
+#define LM3530_ALS_ZB3_REG		0x63
+#define LM3530_ALS_Z0T_REG		0x70
+#define LM3530_ALS_Z1T_REG		0x71
+#define LM3530_ALS_Z2T_REG		0x72
+#define LM3530_ALS_Z3T_REG		0x73
+#define LM3530_ALS_Z4T_REG		0x74
+#define LM3530_REG_MAX			14
+
+/* General Control Register */
+#define LM3530_EN_I2C_SHIFT		(0)
+#define LM3530_RAMP_LAW_SHIFT		(1)
+#define LM3530_MAX_CURR_SHIFT		(2)
+#define LM3530_EN_PWM_SHIFT		(5)
+#define LM3530_PWM_POL_SHIFT		(6)
+#define LM3530_EN_PWM_SIMPLE_SHIFT	(7)
+
+#define LM3530_ENABLE_I2C		(1 << LM3530_EN_I2C_SHIFT)
+#define LM3530_ENABLE_PWM		(1 << LM3530_EN_PWM_SHIFT)
+#define LM3530_POL_LOW			(1 << LM3530_PWM_POL_SHIFT)
+#define LM3530_ENABLE_PWM_SIMPLE	(1 << LM3530_EN_PWM_SIMPLE_SHIFT)
+
+/* ALS Config Register Options */
+#define LM3530_ALS_AVG_TIME_SHIFT	(0)
+#define LM3530_EN_ALS_SHIFT		(3)
+#define LM3530_ALS_SEL_SHIFT		(5)
+
+#define LM3530_ENABLE_ALS		(3 << LM3530_EN_ALS_SHIFT)
+
+/* Brightness Ramp Rate Register */
+#define LM3530_BRT_RAMP_FALL_SHIFT	(0)
+#define LM3530_BRT_RAMP_RISE_SHIFT	(3)
+
+/* ALS Resistor Select */
+#define LM3530_ALS1_IMP_SHIFT		(0)
+#define LM3530_ALS2_IMP_SHIFT		(4)
+
+/* Zone Boundary Register defaults */
+#define LM3530_ALS_ZB_MAX		(4)
+#define LM3530_ALS_WINDOW_mV		(1000)
+#define LM3530_ALS_OFFSET_mV		(4)
+
+/* Zone Target Register defaults */
+#define LM3530_DEF_ZT_0			(0x7F)
+#define LM3530_DEF_ZT_1			(0x66)
+#define LM3530_DEF_ZT_2			(0x4C)
+#define LM3530_DEF_ZT_3			(0x33)
+#define LM3530_DEF_ZT_4			(0x19)
+
+/* 7 bits are used for the brightness : LM3530_BRT_CTRL_REG */
+#define MAX_BRIGHTNESS			(127)
+
+struct lm3530_mode_map {
+	const char *mode;
+	enum lm3530_mode mode_val;
+};
+
+static struct lm3530_mode_map mode_map[] = {
+	{ "man", LM3530_BL_MODE_MANUAL },
+	{ "als", LM3530_BL_MODE_ALS },
+	{ "pwm", LM3530_BL_MODE_PWM },
+};
+
+/**
+ * struct lm3530_data
+ * @led_dev: led class device
+ * @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;
+};
+
+/*
+ * struct lm3530_als_data
+ * @config  : value of ALS configuration register
+ * @imp_sel : value of ALS resistor select register
+ * @zone    : values of ALS ZB(Zone Boundary) registers
+ */
+struct lm3530_als_data {
+	u8 config;
+	u8 imp_sel;
+	u8 zones[LM3530_ALS_ZB_MAX];
+};
+
+static const u8 lm3530_reg[LM3530_REG_MAX] = {
+	LM3530_GEN_CONFIG,
+	LM3530_ALS_CONFIG,
+	LM3530_BRT_RAMP_RATE,
+	LM3530_ALS_IMP_SELECT,
+	LM3530_BRT_CTRL_REG,
+	LM3530_ALS_ZB0_REG,
+	LM3530_ALS_ZB1_REG,
+	LM3530_ALS_ZB2_REG,
+	LM3530_ALS_ZB3_REG,
+	LM3530_ALS_Z0T_REG,
+	LM3530_ALS_Z1T_REG,
+	LM3530_ALS_Z2T_REG,
+	LM3530_ALS_Z3T_REG,
+	LM3530_ALS_Z4T_REG,
+};
+
+static int lm3530_get_mode_from_str(const char *str)
+{
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(mode_map); i++)
+		if (sysfs_streq(str, mode_map[i].mode))
+			return mode_map[i].mode_val;
+
+	return -EINVAL;
+}
+
+static void lm3530_als_configure(struct lm3530_platform_data *pdata,
+				struct lm3530_als_data *als)
+{
+	int i;
+	u32 als_vmin, als_vmax, als_vstep;
+
+	if (pdata->als_vmax == 0) {
+		pdata->als_vmin = 0;
+		pdata->als_vmax = LM3530_ALS_WINDOW_mV;
+	}
+
+	als_vmin = pdata->als_vmin;
+	als_vmax = pdata->als_vmax;
+
+	if ((als_vmax - als_vmin) > LM3530_ALS_WINDOW_mV)
+		pdata->als_vmax = als_vmax = als_vmin + LM3530_ALS_WINDOW_mV;
+
+	/* n zone boundary makes n+1 zones */
+	als_vstep = (als_vmax - als_vmin) / (LM3530_ALS_ZB_MAX + 1);
+
+	for (i = 0; i < LM3530_ALS_ZB_MAX; i++)
+		als->zones[i] = (((als_vmin + LM3530_ALS_OFFSET_mV) +
+			als_vstep + (i * als_vstep)) * LED_FULL) / 1000;
+
+	als->config =
+		(pdata->als_avrg_time << LM3530_ALS_AVG_TIME_SHIFT) |
+		(LM3530_ENABLE_ALS) |
+		(pdata->als_input_mode << LM3530_ALS_SEL_SHIFT);
+
+	als->imp_sel =
+		(pdata->als1_resistor_sel << LM3530_ALS1_IMP_SHIFT) |
+		(pdata->als2_resistor_sel << LM3530_ALS2_IMP_SHIFT);
+}
+
+static int lm3530_led_enable(struct lm3530_data *drvdata)
+{
+	int ret;
+
+	if (drvdata->enable)
+		return 0;
+
+	ret = regulator_enable(drvdata->regulator);
+	if (ret) {
+		dev_err(drvdata->led_dev.dev, "Failed to enable vin:%d\n", ret);
+		return ret;
+	}
+
+	drvdata->enable = true;
+	return 0;
+}
+
+static void lm3530_led_disable(struct lm3530_data *drvdata)
+{
+	int ret;
+
+	if (!drvdata->enable)
+		return;
+
+	ret = regulator_disable(drvdata->regulator);
+	if (ret) {
+		dev_err(drvdata->led_dev.dev, "Failed to disable vin:%d\n",
+			ret);
+		return;
+	}
+
+	drvdata->enable = false;
+}
+
+static int lm3530_init_registers(struct lm3530_data *drvdata)
+{
+	int ret = 0;
+	int i;
+	u8 gen_config;
+	u8 brt_ramp;
+	u8 brightness;
+	u8 reg_val[LM3530_REG_MAX];
+	struct lm3530_platform_data *pdata = drvdata->pdata;
+	struct i2c_client *client = drvdata->client;
+	struct lm3530_pwm_data *pwm = &pdata->pwm_data;
+	struct lm3530_als_data als;
+
+	memset(&als, 0, sizeof(struct lm3530_als_data));
+
+	gen_config = (pdata->brt_ramp_law << LM3530_RAMP_LAW_SHIFT) |
+			((pdata->max_current & 7) << LM3530_MAX_CURR_SHIFT);
+
+	switch (drvdata->mode) {
+	case LM3530_BL_MODE_MANUAL:
+		gen_config |= LM3530_ENABLE_I2C;
+		break;
+	case LM3530_BL_MODE_ALS:
+		gen_config |= LM3530_ENABLE_I2C;
+		lm3530_als_configure(pdata, &als);
+		break;
+	case LM3530_BL_MODE_PWM:
+		gen_config |= LM3530_ENABLE_PWM | LM3530_ENABLE_PWM_SIMPLE |
+			      (pdata->pwm_pol_hi << LM3530_PWM_POL_SHIFT);
+		break;
+	}
+
+	brt_ramp = (pdata->brt_ramp_fall << LM3530_BRT_RAMP_FALL_SHIFT) |
+			(pdata->brt_ramp_rise << LM3530_BRT_RAMP_RISE_SHIFT);
+
+	if (drvdata->brightness)
+		brightness = drvdata->brightness;
+	else
+		brightness = drvdata->brightness = pdata->brt_val;
+
+	if (brightness > drvdata->led_dev.max_brightness)
+		brightness = drvdata->led_dev.max_brightness;
+
+	reg_val[0] = gen_config;	/* LM3530_GEN_CONFIG */
+	reg_val[1] = als.config;	/* LM3530_ALS_CONFIG */
+	reg_val[2] = brt_ramp;		/* LM3530_BRT_RAMP_RATE */
+	reg_val[3] = als.imp_sel;	/* LM3530_ALS_IMP_SELECT */
+	reg_val[4] = brightness;	/* LM3530_BRT_CTRL_REG */
+	reg_val[5] = als.zones[0];	/* LM3530_ALS_ZB0_REG */
+	reg_val[6] = als.zones[1];	/* LM3530_ALS_ZB1_REG */
+	reg_val[7] = als.zones[2];	/* LM3530_ALS_ZB2_REG */
+	reg_val[8] = als.zones[3];	/* LM3530_ALS_ZB3_REG */
+	reg_val[9] = LM3530_DEF_ZT_0;	/* LM3530_ALS_Z0T_REG */
+	reg_val[10] = LM3530_DEF_ZT_1;	/* LM3530_ALS_Z1T_REG */
+	reg_val[11] = LM3530_DEF_ZT_2;	/* LM3530_ALS_Z2T_REG */
+	reg_val[12] = LM3530_DEF_ZT_3;	/* LM3530_ALS_Z3T_REG */
+	reg_val[13] = LM3530_DEF_ZT_4;	/* LM3530_ALS_Z4T_REG */
+
+	ret = lm3530_led_enable(drvdata);
+	if (ret)
+		return ret;
+
+	for (i = 0; i < LM3530_REG_MAX; i++) {
+		/* do not update brightness register when pwm mode */
+		if (lm3530_reg[i] == LM3530_BRT_CTRL_REG &&
+		    drvdata->mode == LM3530_BL_MODE_PWM) {
+			if (pwm->pwm_set_intensity)
+				pwm->pwm_set_intensity(reg_val[i],
+					drvdata->led_dev.max_brightness);
+			continue;
+		}
+
+		ret = i2c_smbus_write_byte_data(client,
+				lm3530_reg[i], reg_val[i]);
+		if (ret)
+			break;
+	}
+
+	return ret;
+}
+
+static void lm3530_brightness_set(struct led_classdev *led_cdev,
+				     enum led_brightness brt_val)
+{
+	int err;
+	struct lm3530_data *drvdata =
+	    container_of(led_cdev, struct lm3530_data, led_dev);
+	struct lm3530_platform_data *pdata = drvdata->pdata;
+	struct lm3530_pwm_data *pwm = &pdata->pwm_data;
+	u8 max_brightness = led_cdev->max_brightness;
+
+	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);
+		if (err)
+			dev_err(&drvdata->client->dev,
+				"Unable to set brightness: %d\n", err);
+		else
+			drvdata->brightness = brt_val;
+
+		if (brt_val == 0)
+			lm3530_led_disable(drvdata);
+		break;
+	case LM3530_BL_MODE_ALS:
+		break;
+	case LM3530_BL_MODE_PWM:
+		if (pwm->pwm_set_intensity)
+			pwm->pwm_set_intensity(brt_val, max_brightness);
+		break;
+	default:
+		break;
+	}
+}
+
+static ssize_t lm3530_mode_get(struct device *dev,
+		struct device_attribute *attr, char *buf)
+{
+	struct led_classdev *led_cdev = dev_get_drvdata(dev);
+	struct lm3530_data *drvdata;
+	int i, len = 0;
+
+	drvdata = container_of(led_cdev, struct lm3530_data, led_dev);
+	for (i = 0; i < ARRAY_SIZE(mode_map); i++)
+		if (drvdata->mode == mode_map[i].mode_val)
+			len += sprintf(buf + len, "[%s] ", mode_map[i].mode);
+		else
+			len += sprintf(buf + len, "%s ", mode_map[i].mode);
+
+	len += sprintf(buf + len, "\n");
+
+	return len;
+}
+
+static ssize_t lm3530_mode_set(struct device *dev, struct device_attribute
+				   *attr, const char *buf, size_t size)
+{
+	struct led_classdev *led_cdev = dev_get_drvdata(dev);
+	struct lm3530_data *drvdata;
+	struct lm3530_pwm_data *pwm;
+	u8 max_brightness;
+	int mode, err;
+
+	drvdata = container_of(led_cdev, struct lm3530_data, led_dev);
+	pwm = &drvdata->pdata->pwm_data;
+	max_brightness = led_cdev->max_brightness;
+	mode = lm3530_get_mode_from_str(buf);
+	if (mode < 0) {
+		dev_err(dev, "Invalid mode\n");
+		return mode;
+	}
+
+	drvdata->mode = mode;
+
+	/* set pwm to low if unnecessary */
+	if (mode != LM3530_BL_MODE_PWM && pwm->pwm_set_intensity)
+		pwm->pwm_set_intensity(0, max_brightness);
+
+	err = lm3530_init_registers(drvdata);
+	if (err) {
+		dev_err(dev, "Setting %s Mode failed :%d\n", buf, err);
+		return err;
+	}
+
+	return sizeof(drvdata->mode);
+}
+static DEVICE_ATTR(mode, 0644, lm3530_mode_get, lm3530_mode_set);
+
+static struct attribute *lm3530_attrs[] = {
+	&dev_attr_mode.attr,
+	NULL
+};
+ATTRIBUTE_GROUPS(lm3530);
+
+static int lm3530_probe(struct i2c_client *client,
+			   const struct i2c_device_id *id)
+{
+	struct lm3530_platform_data *pdata = dev_get_platdata(&client->dev);
+	struct lm3530_data *drvdata;
+	int err = 0;
+
+	if (pdata == NULL) {
+		dev_err(&client->dev, "platform data required\n");
+		return -ENODEV;
+	}
+
+	/* BL mode */
+	if (pdata->mode > LM3530_BL_MODE_PWM) {
+		dev_err(&client->dev, "Illegal Mode request\n");
+		return -EINVAL;
+	}
+
+	if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
+		dev_err(&client->dev, "I2C_FUNC_I2C not supported\n");
+		return -EIO;
+	}
+
+	drvdata = devm_kzalloc(&client->dev, sizeof(struct lm3530_data),
+				GFP_KERNEL);
+	if (drvdata == NULL)
+		return -ENOMEM;
+
+	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;
+	drvdata->led_dev.max_brightness = MAX_BRIGHTNESS;
+	drvdata->led_dev.groups = lm3530_groups;
+
+	i2c_set_clientdata(client, drvdata);
+
+	drvdata->regulator = devm_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;
+		return err;
+	}
+
+	if (drvdata->pdata->brt_val) {
+		err = lm3530_init_registers(drvdata);
+		if (err < 0) {
+			dev_err(&client->dev,
+				"Register Init failed: %d\n", err);
+			return err;
+		}
+	}
+	err = led_classdev_register(&client->dev, &drvdata->led_dev);
+	if (err < 0) {
+		dev_err(&client->dev, "Register led class failed: %d\n", err);
+		return err;
+	}
+
+	return 0;
+}
+
+static int lm3530_remove(struct i2c_client *client)
+{
+	struct lm3530_data *drvdata = i2c_get_clientdata(client);
+
+	lm3530_led_disable(drvdata);
+	led_classdev_unregister(&drvdata->led_dev);
+	return 0;
+}
+
+static const struct i2c_device_id lm3530_id[] = {
+	{LM3530_NAME, 0},
+	{}
+};
+MODULE_DEVICE_TABLE(i2c, lm3530_id);
+
+static struct i2c_driver lm3530_i2c_driver = {
+	.probe = lm3530_probe,
+	.remove = lm3530_remove,
+	.id_table = lm3530_id,
+	.driver = {
+		.name = LM3530_NAME,
+	},
+};
+
+module_i2c_driver(lm3530_i2c_driver);
+
+MODULE_DESCRIPTION("Back Light driver for LM3530");
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Shreshtha Kumar SAHU <shreshthakumar.sahu@stericsson.com>");