regulator: lp8755: new driver for LP8755

This patch is for new lp8755 regulator dirver and
several unsed variables were deleted and then test was done.

LP8755 :
The LP8755 is a high performance power management unit.It contains
six step-down DC-DC converters which can can be filexibly bundled
together in multiphase converters as required by application.
www.ti.com

Signed-off-by: Daniel Jeong <gshark.jeong@gmail.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

1 files changed, 580 insertions, 0 deletions

diff --git a/drivers/regulator/lp8755.c b/drivers/regulator/lp8755.c
new file mode 100644
index 000000000000..dbc4d1254ca1
--- /dev/null
+++ b/drivers/regulator/lp8755.c
@@ -0,0 +1,580 @@
+/*
+ * LP8755 High Performance Power Management Unit : System Interface Driver
+ * (based on rev. 0.26)
+ * Copyright 2012 Texas Instruments
+ *
+ * Author: Daniel(Geon Si) Jeong <daniel.jeong@ti.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/i2c.h>
+#include <linux/err.h>
+#include <linux/irq.h>
+#include <linux/interrupt.h>
+#include <linux/gpio.h>
+#include <linux/regmap.h>
+#include <linux/delay.h>
+#include <linux/uaccess.h>
+#include <linux/regulator/driver.h>
+#include <linux/regulator/machine.h>
+#include <linux/platform_data/lp8755.h>
+
+#define LP8755_REG_BUCK0	0x00
+#define LP8755_REG_BUCK1	0x03
+#define LP8755_REG_BUCK2	0x04
+#define LP8755_REG_BUCK3	0x01
+#define LP8755_REG_BUCK4	0x05
+#define LP8755_REG_BUCK5	0x02
+#define LP8755_REG_MAX		0xFF
+
+#define LP8755_BUCK_EN_M	BIT(7)
+#define LP8755_BUCK_LINEAR_OUT_MAX	0x76
+#define LP8755_BUCK_VOUT_M	0x7F
+
+enum bucks {
+	BUCK0 = 0,
+	BUCK1,
+	BUCK2,
+	BUCK3,
+	BUCK4,
+	BUCK5,
+};
+
+struct lp8755_mphase {
+	int nreg;
+	int buck_num[LP8755_BUCK_MAX];
+};
+
+struct lp8755_chip {
+	struct device *dev;
+	struct regmap *regmap;
+	struct lp8755_platform_data *pdata;
+
+	int irq;
+	unsigned int irqmask;
+
+	int mphase;
+	struct regulator_dev *rdev[LP8755_BUCK_MAX];
+};
+
+/**
+ *lp8755_read : read a single register value from lp8755.
+ *@pchip : device to read from
+ *@reg   : register to read from
+ *@val   : pointer to store read value
+ */
+static int lp8755_read(struct lp8755_chip *pchip, unsigned int reg,
+		       unsigned int *val)
+{
+	return regmap_read(pchip->regmap, reg, val);
+}
+
+/**
+ *lp8755_write : write a single register value to lp8755.
+ *@pchip : device to write to
+ *@reg   : register to write to
+ *@val   : value to be written
+ */
+static int lp8755_write(struct lp8755_chip *pchip, unsigned int reg,
+			unsigned int val)
+{
+	return regmap_write(pchip->regmap, reg, val);
+}
+
+/**
+ *lp8755_update_bits : set the values of bit fields in lp8755 register.
+ *@pchip : device to read from
+ *@reg   : register to update
+ *@mask  : bitmask to be changed
+ *@val   : value for bitmask
+ */
+static int lp8755_update_bits(struct lp8755_chip *pchip, unsigned int reg,
+			      unsigned int mask, unsigned int val)
+{
+	return regmap_update_bits(pchip->regmap, reg, mask, val);
+}
+
+static int lp8755_buck_enable_time(struct regulator_dev *rdev)
+{
+	int ret;
+	unsigned int regval;
+	enum lp8755_bucks id = rdev_get_id(rdev);
+	struct lp8755_chip *pchip = rdev_get_drvdata(rdev);
+
+	ret = lp8755_read(pchip, 0x12 + id, &regval);
+	if (ret < 0) {
+		dev_err(pchip->dev, "i2c acceess error %s\n", __func__);
+		return ret;
+	}
+	return (regval & 0xff) * 100;
+}
+
+static int lp8755_buck_set_mode(struct regulator_dev *rdev, unsigned int mode)
+{
+	int ret;
+	unsigned int regbval = 0x0;
+	enum lp8755_bucks id = rdev_get_id(rdev);
+	struct lp8755_chip *pchip = rdev_get_drvdata(rdev);
+
+	switch (mode) {
+	case REGULATOR_MODE_FAST:
+		/* forced pwm mode */
+		regbval = (0x01 << id);
+		break;
+	case REGULATOR_MODE_NORMAL:
+		/* enable automatic pwm/pfm mode */
+		ret = lp8755_update_bits(pchip, 0x08 + id, 0x20, 0x00);
+		if (ret < 0)
+			goto err_i2c;
+		break;
+	case REGULATOR_MODE_IDLE:
+		/* enable automatic pwm/pfm/lppfm mode */
+		ret = lp8755_update_bits(pchip, 0x08 + id, 0x20, 0x20);
+		if (ret < 0)
+			goto err_i2c;
+
+		ret = lp8755_update_bits(pchip, 0x10, 0x01, 0x01);
+		if (ret < 0)
+			goto err_i2c;
+		break;
+	default:
+		dev_err(pchip->dev, "Not supported buck mode %s\n", __func__);
+		/* forced pwm mode */
+		regbval = (0x01 << id);
+	}
+
+	ret = lp8755_update_bits(pchip, 0x06, 0x01 << id, regbval);
+	if (ret < 0)
+		goto err_i2c;
+	return ret;
+err_i2c:
+	dev_err(pchip->dev, "i2c acceess error %s\n", __func__);
+	return ret;
+}
+
+static unsigned int lp8755_buck_get_mode(struct regulator_dev *rdev)
+{
+	int ret;
+	unsigned int regval;
+	enum lp8755_bucks id = rdev_get_id(rdev);
+	struct lp8755_chip *pchip = rdev_get_drvdata(rdev);
+
+	ret = lp8755_read(pchip, 0x06, &regval);
+	if (ret < 0)
+		goto err_i2c;
+
+	/* mode fast means forced pwm mode */
+	if (regval & (0x01 << id))
+		return REGULATOR_MODE_FAST;
+
+	ret = lp8755_read(pchip, 0x08 + id, &regval);
+	if (ret < 0)
+		goto err_i2c;
+
+	/* mode idle means automatic pwm/pfm/lppfm mode */
+	if (regval & 0x20)
+		return REGULATOR_MODE_IDLE;
+
+	/* mode normal means automatic pwm/pfm mode */
+	return REGULATOR_MODE_NORMAL;
+
+err_i2c:
+	dev_err(pchip->dev, "i2c acceess error %s\n", __func__);
+	return 0;
+}
+
+static int lp8755_buck_set_ramp(struct regulator_dev *rdev, int ramp)
+{
+	int ret;
+	unsigned int regval = 0x00;
+	enum lp8755_bucks id = rdev_get_id(rdev);
+	struct lp8755_chip *pchip = rdev_get_drvdata(rdev);
+
+	/* uV/us */
+	switch (ramp) {
+	case 0 ... 230:
+		regval = 0x07;
+		break;
+	case 231 ... 470:
+		regval = 0x06;
+		break;
+	case 471 ... 940:
+		regval = 0x05;
+		break;
+	case 941 ... 1900:
+		regval = 0x04;
+		break;
+	case 1901 ... 3800:
+		regval = 0x03;
+		break;
+	case 3801 ... 7500:
+		regval = 0x02;
+		break;
+	case 7501 ... 15000:
+		regval = 0x01;
+		break;
+	case 15001 ... 30000:
+		regval = 0x00;
+		break;
+	default:
+		dev_err(pchip->dev,
+			"Not supported ramp value %d %s\n", ramp, __func__);
+		return -EINVAL;
+	}
+
+	ret = lp8755_update_bits(pchip, 0x07 + id, 0x07, regval);
+	if (ret < 0)
+		goto err_i2c;
+	return ret;
+err_i2c:
+	dev_err(pchip->dev, "i2c acceess error %s\n", __func__);
+	return ret;
+}
+
+static struct regulator_ops lp8755_buck_ops = {
+	.list_voltage = regulator_list_voltage_linear,
+	.set_voltage_sel = regulator_set_voltage_sel_regmap,
+	.get_voltage_sel = regulator_get_voltage_sel_regmap,
+	.enable = regulator_enable_regmap,
+	.disable = regulator_disable_regmap,
+	.is_enabled = regulator_is_enabled_regmap,
+	.enable_time = lp8755_buck_enable_time,
+	.set_mode = lp8755_buck_set_mode,
+	.get_mode = lp8755_buck_get_mode,
+	.set_ramp_delay = lp8755_buck_set_ramp,
+};
+
+#define lp8755_rail(_id) "lp8755_buck"#_id
+#define lp8755_buck_init(_id)\
+{\
+	.constraints = {\
+		.name = lp8755_rail(_id),\
+		.valid_ops_mask = REGULATOR_CHANGE_VOLTAGE,\
+		.min_uV = 500000,\
+		.max_uV = 1675000,\
+	},\
+}
+
+static struct regulator_init_data lp8755_reg_default[LP8755_BUCK_MAX] = {
+	[BUCK0] = lp8755_buck_init(0),
+	[BUCK1] = lp8755_buck_init(1),
+	[BUCK2] = lp8755_buck_init(2),
+	[BUCK3] = lp8755_buck_init(3),
+	[BUCK4] = lp8755_buck_init(4),
+	[BUCK5] = lp8755_buck_init(5),
+};
+
+static const struct lp8755_mphase mphase_buck[MPHASE_CONF_MAX] = {
+	{3, {BUCK0, BUCK3, BUCK5}
+	 },
+	{6, {BUCK0, BUCK1, BUCK2, BUCK3, BUCK4, BUCK5}
+	 },
+	{5, {BUCK0, BUCK2, BUCK3, BUCK4, BUCK5}
+	 },
+	{4, {BUCK0, BUCK3, BUCK4, BUCK5}
+	 },
+	{3, {BUCK0, BUCK4, BUCK5}
+	 },
+	{2, {BUCK0, BUCK5}
+	 },
+	{1, {BUCK0}
+	 },
+	{2, {BUCK0, BUCK3}
+	 },
+	{4, {BUCK0, BUCK2, BUCK3, BUCK5}
+	 },
+};
+
+static int lp8755_init_data(struct lp8755_chip *pchip)
+{
+	unsigned int regval;
+	int ret, icnt, buck_num;
+	struct lp8755_platform_data *pdata = pchip->pdata;
+
+	/* read back  muti-phase configuration */
+	ret = lp8755_read(pchip, 0x3D, &regval);
+	if (ret < 0)
+		goto out_i2c_error;
+	pchip->mphase = regval & 0x07;
+
+	/* set default data based on multi-phase config */
+	for (icnt = 0; icnt < mphase_buck[pchip->mphase].nreg; icnt++) {
+		buck_num = mphase_buck[pchip->mphase].buck_num[icnt];
+		pdata->buck_data[buck_num] = &lp8755_reg_default[buck_num];
+	}
+	return ret;
+
+out_i2c_error:
+	dev_err(pchip->dev, "i2c acceess error %s\n", __func__);
+	return ret;
+}
+
+#define lp8755_buck_desc(_id)\
+{\
+	.name = lp8755_rail(_id),\
+	.id   = LP8755_BUCK##_id,\
+	.ops  = &lp8755_buck_ops,\
+	.n_voltages = LP8755_BUCK_LINEAR_OUT_MAX+1,\
+	.uV_step = 10000,\
+	.min_uV = 500000,\
+	.type = REGULATOR_VOLTAGE,\
+	.owner = THIS_MODULE,\
+	.enable_reg = LP8755_REG_BUCK##_id,\
+	.enable_mask = LP8755_BUCK_EN_M,\
+	.vsel_reg = LP8755_REG_BUCK##_id,\
+	.vsel_mask = LP8755_BUCK_VOUT_M,\
+}
+
+static struct regulator_desc lp8755_regulators[] = {
+	lp8755_buck_desc(0),
+	lp8755_buck_desc(1),
+	lp8755_buck_desc(2),
+	lp8755_buck_desc(3),
+	lp8755_buck_desc(4),
+	lp8755_buck_desc(5),
+};
+
+static int lp8755_regulator_init(struct lp8755_chip *pchip)
+{
+	int ret, icnt, buck_num;
+	struct lp8755_platform_data *pdata = pchip->pdata;
+	struct regulator_config rconfig = { };
+
+	rconfig.regmap = pchip->regmap;
+	rconfig.dev = pchip->dev;
+	rconfig.driver_data = pchip;
+
+	for (icnt = 0; icnt < mphase_buck[pchip->mphase].nreg; icnt++) {
+		buck_num = mphase_buck[pchip->mphase].buck_num[icnt];
+		rconfig.init_data = pdata->buck_data[buck_num];
+		rconfig.of_node = pchip->dev->of_node;
+		pchip->rdev[buck_num] =
+		    regulator_register(&lp8755_regulators[buck_num], &rconfig);
+		if (IS_ERR(pchip->rdev[buck_num])) {
+			ret = PTR_ERR(pchip->rdev[buck_num]);
+			dev_err(pchip->dev, "regulator init failed: buck 0\n");
+			goto err_buck;
+		}
+	}
+
+	return 0;
+
+err_buck:
+	for (icnt = 0; icnt < LP8755_BUCK_MAX; icnt++)
+		if (pchip->rdev[icnt] != NULL)
+			regulator_unregister(pchip->rdev[icnt]);
+	return ret;
+}
+
+static irqreturn_t lp8755_irq_handler(int irq, void *data)
+{
+	int ret, icnt;
+	unsigned int flag0, flag1;
+	struct lp8755_chip *pchip = data;
+
+	/* read flag0 register */
+	ret = lp8755_read(pchip, 0x0D, &flag0);
+	if (ret < 0)
+		goto err_i2c;
+	/* clear flag register to pull up int. pin */
+	ret = lp8755_write(pchip, 0x0D, 0x00);
+	if (ret < 0)
+		goto err_i2c;
+
+	/* sent power fault detection event to specific regulator */
+	for (icnt = 0; icnt < 6; icnt++)
+		if ((flag0 & (0x4 << icnt))
+		    && (pchip->irqmask & (0x04 << icnt))
+		    && (pchip->rdev[icnt] != NULL))
+			regulator_notifier_call_chain(pchip->rdev[icnt],
+						      LP8755_EVENT_PWR_FAULT,
+						      NULL);
+
+	/* read flag1 register */
+	ret = lp8755_read(pchip, 0x0E, &flag1);
+	if (ret < 0)
+		goto err_i2c;
+	/* clear flag register to pull up int. pin */
+	ret = lp8755_write(pchip, 0x0E, 0x00);
+	if (ret < 0)
+		goto err_i2c;
+
+	/* send OCP event to all regualtor devices */
+	if ((flag1 & 0x01) && (pchip->irqmask & 0x01))
+		for (icnt = 0; icnt < LP8755_BUCK_MAX; icnt++)
+			if (pchip->rdev[icnt] != NULL)
+				regulator_notifier_call_chain(pchip->rdev[icnt],
+							      LP8755_EVENT_OCP,
+							      NULL);
+
+	/* send OVP event to all regualtor devices */
+	if ((flag1 & 0x02) && (pchip->irqmask & 0x02))
+		for (icnt = 0; icnt < LP8755_BUCK_MAX; icnt++)
+			if (pchip->rdev[icnt] != NULL)
+				regulator_notifier_call_chain(pchip->rdev[icnt],
+							      LP8755_EVENT_OVP,
+							      NULL);
+	return IRQ_HANDLED;
+
+err_i2c:
+	dev_err(pchip->dev, "i2c acceess error %s\n", __func__);
+	return IRQ_NONE;
+}
+
+static int lp8755_int_config(struct lp8755_chip *pchip)
+{
+	int ret;
+	unsigned int regval;
+
+	if (pchip->irq == 0) {
+		dev_warn(pchip->dev, "not use interrupt : %s\n", __func__);
+		return 0;
+	}
+
+	ret = lp8755_read(pchip, 0x0F, &regval);
+	if (ret < 0)
+		goto err_i2c;
+	pchip->irqmask = regval;
+	ret = request_threaded_irq(pchip->irq, NULL, lp8755_irq_handler,
+				   IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
+				   "lp8755-irq", pchip);
+	if (ret)
+		return ret;
+
+	return ret;
+
+err_i2c:
+	dev_err(pchip->dev, "i2c acceess error %s\n", __func__);
+	return ret;
+}
+
+static const struct regmap_config lp8755_regmap = {
+	.reg_bits = 8,
+	.val_bits = 8,
+	.max_register = LP8755_REG_MAX,
+};
+
+static int lp8755_probe(struct i2c_client *client,
+			const struct i2c_device_id *id)
+{
+	int ret, icnt;
+	struct lp8755_chip *pchip;
+	struct lp8755_platform_data *pdata = client->dev.platform_data;
+
+	if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
+		dev_err(&client->dev, "i2c functionality check fail.\n");
+		return -EOPNOTSUPP;
+	}
+
+	pchip = devm_kzalloc(&client->dev,
+			     sizeof(struct lp8755_chip), GFP_KERNEL);
+	if (!pchip)
+		return -ENOMEM;
+
+	pchip->dev = &client->dev;
+	pchip->regmap = devm_regmap_init_i2c(client, &lp8755_regmap);
+	if (IS_ERR(pchip->regmap)) {
+		ret = PTR_ERR(pchip->regmap);
+		dev_err(&client->dev, "fail to allocate regmap %d\n", ret);
+		return ret;
+	}
+	i2c_set_clientdata(client, pchip);
+
+	if (pdata != NULL) {
+		pchip->pdata = pdata;
+		pchip->mphase = pdata->mphase;
+	} else {
+		pchip->pdata = devm_kzalloc(pchip->dev,
+					    sizeof(struct lp8755_platform_data),
+					    GFP_KERNEL);
+		if (!pchip->pdata)
+			return -ENOMEM;
+		ret = lp8755_init_data(pchip);
+		if (ret < 0)
+			goto err_chip_init;
+	}
+
+	ret = lp8755_regulator_init(pchip);
+	if (ret < 0)
+		goto err_regulator;
+
+	pchip->irq = client->irq;
+	ret = lp8755_int_config(pchip);
+	if (ret < 0)
+		goto err_irq;
+
+	return ret;
+
+err_irq:
+	dev_err(&client->dev, "fail to irq config\n");
+
+	for (icnt = 0; icnt < mphase_buck[pchip->mphase].nreg; icnt++)
+		regulator_unregister(pchip->rdev[icnt]);
+
+err_regulator:
+	dev_err(&client->dev, "fail to initialize regulators\n");
+	/* output disable */
+	for (icnt = 0; icnt < 0x06; icnt++)
+		lp8755_write(pchip, icnt, 0x00);
+
+err_chip_init:
+	dev_err(&client->dev, "fail to initialize chip\n");
+	return ret;
+}
+
+static int lp8755_remove(struct i2c_client *client)
+{
+	int icnt;
+	struct lp8755_chip *pchip = i2c_get_clientdata(client);
+
+	for (icnt = 0; icnt < mphase_buck[pchip->mphase].nreg; icnt++)
+		regulator_unregister(pchip->rdev[icnt]);
+
+	for (icnt = 0; icnt < 0x06; icnt++)
+		lp8755_write(pchip, icnt, 0x00);
+
+	if (pchip->irq != 0)
+		free_irq(pchip->irq, pchip);
+
+	return 0;
+}
+
+static const struct i2c_device_id lp8755_id[] = {
+	{LP8755_NAME, 0},
+	{}
+};
+
+MODULE_DEVICE_TABLE(i2c, lp8755_id);
+
+static struct i2c_driver lp8755_i2c_driver = {
+	.driver = {
+		   .name = LP8755_NAME,
+		   },
+	.probe = lp8755_probe,
+	.remove = __devexit_p(lp8755_remove),
+	.id_table = lp8755_id,
+};
+
+static int __init lp8755_init(void)
+{
+	return i2c_add_driver(&lp8755_i2c_driver);
+}
+
+subsys_initcall(lp8755_init);
+
+static void __exit lp8755_exit(void)
+{
+	i2c_del_driver(&lp8755_i2c_driver);
+}
+
+module_exit(lp8755_exit);
+
+MODULE_DESCRIPTION("Texas Instruments lp8755 driver");
+MODULE_AUTHOR("Daniel Jeong <daniel.jeong@ti.com>");
+MODULE_LICENSE("GPL v2");