regulator: da9211: new regulator driver

This is the driver for the Dialog DA9211 Multi-phase 12A DC-DC Buck
Converter regulator. It communicates via an I2C bus to the device.

Signed-off-by: James Ban <james.ban.opensource@diasemi.com>
Signed-off-by: Mark Brown <broonie@linaro.org>

1 files changed, 388 insertions, 0 deletions

diff --git a/drivers/regulator/da9211-regulator.c b/drivers/regulator/da9211-regulator.c
new file mode 100644
index 000000000000..bd1850658a3f
--- /dev/null
+++ b/drivers/regulator/da9211-regulator.c
@@ -0,0 +1,388 @@
+/*
+ * da9211-regulator.c - Regulator device driver for DA9211
+ * Copyright (C) 2014  Dialog Semiconductor Ltd.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Library General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Library General Public License for more details.
+ */
+
+#include <linux/err.h>
+#include <linux/gpio.h>
+#include <linux/i2c.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/regulator/driver.h>
+#include <linux/regulator/machine.h>
+#include <linux/regmap.h>
+#include <linux/irq.h>
+#include <linux/interrupt.h>
+#include <linux/regulator/da9211.h>
+#include "da9211-regulator.h"
+
+#define DA9211_BUCK_MODE_SLEEP	1
+#define DA9211_BUCK_MODE_SYNC	2
+#define DA9211_BUCK_MODE_AUTO	3
+
+/* DA9211 REGULATOR IDs */
+#define DA9211_ID_BUCKA	0
+#define DA9211_ID_BUCKB	1
+
+struct da9211 {
+	struct device *dev;
+	struct regmap *regmap;
+	struct da9211_pdata *pdata;
+	struct regulator_dev *rdev[DA9211_MAX_REGULATORS];
+	int num_regulator;
+	int chip_irq;
+};
+
+static const struct regmap_range_cfg da9211_regmap_range[] = {
+	{
+		.selector_reg = DA9211_REG_PAGE_CON,
+		.selector_mask  = DA9211_REG_PAGE_MASK,
+		.selector_shift = DA9211_REG_PAGE_SHIFT,
+		.window_start = 0,
+		.window_len = 256,
+		.range_min = 0,
+		.range_max = 2*256,
+	},
+};
+
+static const struct regmap_config da9211_regmap_config = {
+	.reg_bits = 8,
+	.val_bits = 8,
+	.max_register = 2 * 256,
+	.ranges = da9211_regmap_range,
+	.num_ranges = ARRAY_SIZE(da9211_regmap_range),
+};
+
+/* Default limits measured in millivolts and milliamps */
+#define DA9211_MIN_MV		300
+#define DA9211_MAX_MV		1570
+#define DA9211_STEP_MV		10
+
+/* Current limits for buck (uA) indices corresponds with register values */
+static const int da9211_current_limits[] = {
+	2000000, 2200000, 2400000, 2600000, 2800000, 3000000, 3200000, 3400000,
+	3600000, 3800000, 4000000, 4200000, 4400000, 4600000, 4800000, 5000000
+};
+
+static unsigned int da9211_buck_get_mode(struct regulator_dev *rdev)
+{
+	int id = rdev_get_id(rdev);
+	struct da9211 *chip = rdev_get_drvdata(rdev);
+	unsigned int data;
+	int ret, mode = 0;
+
+	ret = regmap_read(chip->regmap, DA9211_REG_BUCKA_CONF+id, &data);
+	if (ret < 0)
+		return ret;
+
+	switch (data & 0x03) {
+	case DA9211_BUCK_MODE_SYNC:
+		mode = REGULATOR_MODE_FAST;
+		break;
+	case DA9211_BUCK_MODE_AUTO:
+		mode = REGULATOR_MODE_NORMAL;
+		break;
+	case DA9211_BUCK_MODE_SLEEP:
+		mode = REGULATOR_MODE_STANDBY;
+		break;
+	}
+
+	return mode;
+}
+
+static int da9211_buck_set_mode(struct regulator_dev *rdev,
+					unsigned int mode)
+{
+	int id = rdev_get_id(rdev);
+	struct da9211 *chip = rdev_get_drvdata(rdev);
+	int val = 0;
+
+	switch (mode) {
+	case REGULATOR_MODE_FAST:
+		val = DA9211_BUCK_MODE_SYNC;
+		break;
+	case REGULATOR_MODE_NORMAL:
+		val = DA9211_BUCK_MODE_AUTO;
+		break;
+	case REGULATOR_MODE_STANDBY:
+		val = DA9211_BUCK_MODE_SLEEP;
+		break;
+	}
+
+	return regmap_update_bits(chip->regmap, DA9211_REG_BUCKA_CONF+id,
+					0x03, val);
+}
+
+static int da9211_set_current_limit(struct regulator_dev *rdev, int min,
+				    int max)
+{
+	int id = rdev_get_id(rdev);
+	struct da9211 *chip = rdev_get_drvdata(rdev);
+	int i;
+
+	/* search for closest to maximum */
+	for (i = ARRAY_SIZE(da9211_current_limits)-1; i >= 0; i--) {
+		if (min <= da9211_current_limits[i] &&
+		    max >= da9211_current_limits[i]) {
+				return regmap_update_bits(chip->regmap,
+					DA9211_REG_BUCK_ILIM,
+					(0x0F << id*4), (i << id*4));
+		}
+	}
+
+	return -EINVAL;
+}
+
+static int da9211_get_current_limit(struct regulator_dev *rdev)
+{
+	int id = rdev_get_id(rdev);
+	struct da9211 *chip = rdev_get_drvdata(rdev);
+	unsigned int data;
+	int ret;
+
+	ret = regmap_read(chip->regmap, DA9211_REG_BUCK_ILIM, &data);
+	if (ret < 0)
+		return ret;
+
+	/* select one of 16 values: 0000 (2000mA) to 1111 (5000mA) */
+	data = (data >> id*4) & 0x0F;
+	return da9211_current_limits[data];
+}
+
+static struct regulator_ops da9211_buck_ops = {
+	.get_mode = da9211_buck_get_mode,
+	.set_mode = da9211_buck_set_mode,
+	.enable = regulator_enable_regmap,
+	.disable = regulator_disable_regmap,
+	.is_enabled = regulator_is_enabled_regmap,
+	.set_voltage_sel = regulator_set_voltage_sel_regmap,
+	.get_voltage_sel = regulator_get_voltage_sel_regmap,
+	.list_voltage = regulator_list_voltage_linear,
+	.set_current_limit = da9211_set_current_limit,
+	.get_current_limit = da9211_get_current_limit,
+};
+
+#define DA9211_BUCK(_id) \
+{\
+	.name = #_id,\
+	.ops = &da9211_buck_ops,\
+	.type = REGULATOR_VOLTAGE,\
+	.id = DA9211_ID_##_id,\
+	.n_voltages = (DA9211_MAX_MV - DA9211_MIN_MV) / DA9211_STEP_MV + 1,\
+	.min_uV = (DA9211_MIN_MV * 1000),\
+	.uV_step = (DA9211_STEP_MV * 1000),\
+	.enable_reg = DA9211_REG_BUCKA_CONT + DA9211_ID_##_id,\
+	.enable_mask = DA9211_BUCKA_EN,\
+	.vsel_reg = DA9211_REG_VBUCKA_A + DA9211_ID_##_id * 2,\
+	.vsel_mask = DA9211_VBUCK_MASK,\
+	.owner = THIS_MODULE,\
+}
+
+static struct regulator_desc da9211_regulators[] = {
+	DA9211_BUCK(BUCKA),
+	DA9211_BUCK(BUCKB),
+};
+
+static irqreturn_t da9211_irq_handler(int irq, void *data)
+{
+	struct da9211 *chip = data;
+	int reg_val, err, ret = IRQ_NONE;
+
+	err = regmap_read(chip->regmap, DA9211_REG_EVENT_B, &reg_val);
+	if (err < 0)
+		goto error_i2c;
+
+	if (reg_val & DA9211_E_OV_CURR_A) {
+		regulator_notifier_call_chain(chip->rdev[0],
+			REGULATOR_EVENT_OVER_CURRENT,
+			rdev_get_drvdata(chip->rdev[0]));
+
+		err = regmap_write(chip->regmap, DA9211_REG_EVENT_B,
+			DA9211_E_OV_CURR_A);
+		if (err < 0)
+			goto error_i2c;
+
+		ret = IRQ_HANDLED;
+	}
+
+	if (reg_val & DA9211_E_OV_CURR_B) {
+		regulator_notifier_call_chain(chip->rdev[1],
+			REGULATOR_EVENT_OVER_CURRENT,
+			rdev_get_drvdata(chip->rdev[1]));
+
+		err = regmap_write(chip->regmap, DA9211_REG_EVENT_B,
+			DA9211_E_OV_CURR_B);
+		if (err < 0)
+			goto error_i2c;
+
+		ret = IRQ_HANDLED;
+	}
+
+	return ret;
+
+error_i2c:
+	dev_err(chip->dev, "I2C error : %d\n", err);
+	return IRQ_NONE;
+}
+
+static int da9211_regulator_init(struct da9211 *chip)
+{
+	struct regulator_config config = { };
+	int i, ret;
+	unsigned int data;
+
+	ret = regmap_read(chip->regmap, DA9211_REG_CONFIG_E, &data);
+	if (ret < 0) {
+		dev_err(chip->dev, "Failed to read CONTROL_E reg: %d\n", ret);
+		goto err;
+	}
+
+	data &= DA9211_SLAVE_SEL;
+	/* If configuration for 1/2 bucks is different between platform data
+	 * and the register, driver should exit.
+	 */
+	if ((chip->pdata->num_buck == 2 && data == 0x40)
+		|| (chip->pdata->num_buck == 1 && data == 0x00)) {
+		if (data == 0)
+			chip->num_regulator = 1;
+		else
+			chip->num_regulator = 2;
+	} else {
+		ret = -EINVAL;
+		dev_err(chip->dev, "Configuration is mismatched\n");
+		goto err;
+	}
+
+	for (i = 0; i < chip->num_regulator; i++) {
+		if (chip->pdata)
+			config.init_data =
+				&(chip->pdata->init_data[i]);
+
+		config.dev = chip->dev;
+		config.driver_data = chip;
+		config.regmap = chip->regmap;
+
+		chip->rdev[i] = devm_regulator_register(chip->dev,
+			&da9211_regulators[i], &config);
+		if (IS_ERR(chip->rdev[i])) {
+			dev_err(chip->dev,
+				"Failed to register DA9211 regulator\n");
+			ret = PTR_ERR(chip->rdev[i]);
+			goto err_regulator;
+		}
+
+		if (chip->chip_irq != 0) {
+			ret = regmap_update_bits(chip->regmap,
+				DA9211_REG_MASK_B, DA9211_M_OV_CURR_A << i, 1);
+			if (ret < 0) {
+				dev_err(chip->dev,
+					"Failed to update mask reg: %d\n", ret);
+				goto err_regulator;
+			}
+		}
+	}
+
+	return 0;
+
+err_regulator:
+	while (--i >= 0)
+		devm_regulator_unregister(chip->dev, chip->rdev[i]);
+err:
+	return ret;
+}
+/*
+ * I2C driver interface functions
+ */
+static int da9211_i2c_probe(struct i2c_client *i2c,
+		const struct i2c_device_id *id)
+{
+	struct da9211 *chip;
+	int error, ret;
+
+	chip = devm_kzalloc(&i2c->dev, sizeof(struct da9211), GFP_KERNEL);
+
+	chip->dev = &i2c->dev;
+	chip->regmap = devm_regmap_init_i2c(i2c, &da9211_regmap_config);
+	if (IS_ERR(chip->regmap)) {
+		error = PTR_ERR(chip->regmap);
+		dev_err(&i2c->dev, "Failed to allocate register map: %d\n",
+			error);
+		return error;
+	}
+
+	i2c_set_clientdata(i2c, chip);
+
+	chip->pdata = i2c->dev.platform_data;
+	if (!chip->pdata) {
+		dev_err(&i2c->dev, "No platform init data supplied\n");
+		return -ENODEV;
+	}
+
+	chip->chip_irq = i2c->irq;
+
+	if (chip->chip_irq != 0) {
+		ret = devm_request_threaded_irq(chip->dev, chip->chip_irq, NULL,
+					da9211_irq_handler,
+					IRQF_TRIGGER_LOW|IRQF_ONESHOT,
+					"da9211", chip);
+		if (ret != 0) {
+			dev_err(chip->dev, "Failed to request IRQ: %d\n",
+				chip->chip_irq);
+			return ret;
+		}
+	} else {
+		dev_warn(chip->dev, "No IRQ configured\n");
+	}
+
+	ret = da9211_regulator_init(chip);
+
+	if (ret < 0)
+		dev_err(&i2c->dev, "Failed to initialize regulator: %d\n", ret);
+
+	return ret;
+}
+
+static int da9211_i2c_remove(struct i2c_client *i2c)
+{
+	struct da9211 *chip = i2c_get_clientdata(i2c);
+	int i;
+
+	for (i = 0; i < chip->num_regulator; i++)
+		devm_regulator_unregister(chip->dev, chip->rdev[i]);
+
+	return 0;
+}
+
+static const struct i2c_device_id da9211_i2c_id[] = {
+	{"da9211", 0},
+	{},
+};
+
+MODULE_DEVICE_TABLE(i2c, da9211_i2c_id);
+
+static struct i2c_driver da9211_regulator_driver = {
+	.driver = {
+		.name = "da9211",
+		.owner = THIS_MODULE,
+	},
+	.probe = da9211_i2c_probe,
+	.remove = da9211_i2c_remove,
+	.id_table = da9211_i2c_id,
+};
+
+module_i2c_driver(da9211_regulator_driver);
+
+MODULE_AUTHOR("James Ban <James.Ban.opensource@diasemi.com>");
+MODULE_DESCRIPTION("Regulator device driver for Dialog DA9211");
+MODULE_LICENSE("GPL v2");