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authorYunfan Zhang <yfzhang@marvell.com>2012-09-08 14:52:18 +0400
committerMark Brown <broonie@opensource.wolfsonmicro.com>2012-09-10 05:55:22 +0400
commit49d8c59927e7887ea168a040e41c22937e10c30b (patch)
tree75ab6cb1fc1b03f252a3e1235cc2dde9e0954bc2 /drivers/regulator/fan53555.c
parent029dd3cefa46ecdd879f9b4e2df3bdf4371cc22c (diff)
downloadlinux-49d8c59927e7887ea168a040e41c22937e10c30b.tar.xz
regulator: Fairchild fan53555 support
This driver supports Fairchild FAN53555 Digitally Programmable TinyBuck Regulator. The FAN53555 is a step-down switching voltage regulator that delivers a digitally programmable output from an input voltage supply of 2.5V to 5.5V. The output voltage is programmed through an I2C interface. Signed-off-by: Yunfan Zhang <yfzhang@marvell.com> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Diffstat (limited to 'drivers/regulator/fan53555.c')
-rw-r--r--drivers/regulator/fan53555.c325
1 files changed, 325 insertions, 0 deletions
diff --git a/drivers/regulator/fan53555.c b/drivers/regulator/fan53555.c
new file mode 100644
index 000000000000..890f2b34b39a
--- /dev/null
+++ b/drivers/regulator/fan53555.c
@@ -0,0 +1,325 @@
+/*
+ * FAN53555 Fairchild Digitally Programmable TinyBuck Regulator Driver.
+ *
+ * Supported Part Numbers:
+ * FAN53555UC00X/01X/03X/04X/05X
+ *
+ * Copyright (c) 2012 Marvell Technology Ltd.
+ * Yunfan Zhang <yfzhang@marvell.com>
+ *
+ * This package 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/param.h>
+#include <linux/err.h>
+#include <linux/platform_device.h>
+#include <linux/regulator/driver.h>
+#include <linux/regulator/machine.h>
+#include <linux/i2c.h>
+#include <linux/slab.h>
+#include <linux/regmap.h>
+#include <linux/regulator/fan53555.h>
+
+/* Voltage setting */
+#define FAN53555_VSEL0 0x00
+#define FAN53555_VSEL1 0x01
+/* Control register */
+#define FAN53555_CONTROL 0x02
+/* IC Type */
+#define FAN53555_ID1 0x03
+/* IC mask version */
+#define FAN53555_ID2 0x04
+/* Monitor register */
+#define FAN53555_MONITOR 0x05
+
+/* VSEL bit definitions */
+#define VSEL_BUCK_EN (1 << 7)
+#define VSEL_MODE (1 << 6)
+#define VSEL_NSEL_MASK 0x3F
+/* Chip ID and Verison */
+#define DIE_ID 0x0F /* ID1 */
+#define DIE_REV 0x0F /* ID2 */
+/* Control bit definitions */
+#define CTL_OUTPUT_DISCHG (1 << 7)
+#define CTL_SLEW_MASK (0x7 << 4)
+#define CTL_SLEW_SHIFT 4
+#define CTL_RESET (1 << 2)
+
+#define FAN53555_NVOLTAGES 64 /* Numbers of voltages */
+
+/* IC Type */
+enum {
+ FAN53555_CHIP_ID_00 = 0,
+ FAN53555_CHIP_ID_01,
+ FAN53555_CHIP_ID_02,
+ FAN53555_CHIP_ID_03,
+ FAN53555_CHIP_ID_04,
+ FAN53555_CHIP_ID_05,
+};
+
+struct fan53555_device_info {
+ struct regmap *regmap;
+ struct device *dev;
+ struct regulator_desc desc;
+ struct regulator_dev *rdev;
+ struct regulator_init_data *regulator;
+ /* IC Type and Rev */
+ int chip_id;
+ int chip_rev;
+ /* Voltage setting register */
+ unsigned int vol_reg;
+ unsigned int sleep_reg;
+ /* Voltage range and step(linear) */
+ unsigned int vsel_min;
+ unsigned int vsel_max;
+ unsigned int vsel_step;
+ /* Voltage slew rate limiting */
+ unsigned int slew_rate;
+ /* Sleep voltage cache */
+ unsigned int sleep_vol_cache;
+};
+
+static int fan53555_set_suspend_voltage(struct regulator_dev *rdev, int uV)
+{
+ struct fan53555_device_info *di = rdev_get_drvdata(rdev);
+ int ret;
+
+ if (di->sleep_vol_cache == uV)
+ return 0;
+ ret = regulator_map_voltage_linear(rdev, uV, uV);
+ if (ret < 0)
+ return -EINVAL;
+ ret = regmap_update_bits(di->regmap, di->sleep_reg,
+ VSEL_NSEL_MASK, ret);
+ if (ret < 0)
+ return -EINVAL;
+ /* Cache the sleep voltage setting.
+ * Might not be the real voltage which is rounded */
+ di->sleep_vol_cache = uV;
+
+ return 0;
+}
+
+static int fan53555_set_mode(struct regulator_dev *rdev, unsigned int mode)
+{
+ struct fan53555_device_info *di = rdev_get_drvdata(rdev);
+
+ switch (mode) {
+ case REGULATOR_MODE_FAST:
+ regmap_update_bits(di->regmap, di->vol_reg,
+ VSEL_MODE, VSEL_MODE);
+ break;
+ case REGULATOR_MODE_NORMAL:
+ regmap_update_bits(di->regmap, di->vol_reg, VSEL_MODE, 0);
+ break;
+ default:
+ return -EINVAL;
+ }
+ return 0;
+}
+
+static unsigned int fan53555_get_mode(struct regulator_dev *rdev)
+{
+ struct fan53555_device_info *di = rdev_get_drvdata(rdev);
+ unsigned int val;
+ int ret = 0;
+
+ ret = regmap_read(di->regmap, di->vol_reg, &val);
+ if (ret < 0)
+ return ret;
+ if (val & VSEL_MODE)
+ return REGULATOR_MODE_FAST;
+ else
+ return REGULATOR_MODE_NORMAL;
+}
+
+static struct regulator_ops fan53555_regulator_ops = {
+ .set_voltage_sel = regulator_set_voltage_sel_regmap,
+ .get_voltage_sel = regulator_get_voltage_sel_regmap,
+ .map_voltage = regulator_map_voltage_linear,
+ .list_voltage = regulator_list_voltage_linear,
+ .set_suspend_voltage = fan53555_set_suspend_voltage,
+ .enable = regulator_enable_regmap,
+ .disable = regulator_disable_regmap,
+ .is_enabled = regulator_is_enabled_regmap,
+ .set_mode = fan53555_set_mode,
+ .get_mode = fan53555_get_mode,
+};
+
+/* For 00,01,03,05 options:
+ * VOUT = 0.60V + NSELx * 10mV, from 0.60 to 1.23V.
+ * For 04 option:
+ * VOUT = 0.603V + NSELx * 12.826mV, from 0.603 to 1.411V.
+ * */
+static int fan53555_device_setup(struct fan53555_device_info *di,
+ struct fan53555_platform_data *pdata)
+{
+ unsigned int reg, data, mask;
+
+ /* Setup voltage control register */
+ switch (pdata->sleep_vsel_id) {
+ case FAN53555_VSEL_ID_0:
+ di->sleep_reg = FAN53555_VSEL0;
+ di->vol_reg = FAN53555_VSEL1;
+ break;
+ case FAN53555_VSEL_ID_1:
+ di->sleep_reg = FAN53555_VSEL1;
+ di->vol_reg = FAN53555_VSEL0;
+ break;
+ default:
+ dev_err(di->dev, "Invalid VSEL ID!\n");
+ return -EINVAL;
+ }
+ /* Init voltage range and step */
+ switch (di->chip_id) {
+ case FAN53555_CHIP_ID_00:
+ case FAN53555_CHIP_ID_01:
+ case FAN53555_CHIP_ID_03:
+ case FAN53555_CHIP_ID_05:
+ di->vsel_min = 600000;
+ di->vsel_max = 1230000;
+ di->vsel_step = 10000;
+ break;
+ case FAN53555_CHIP_ID_04:
+ di->vsel_min = 603000;
+ di->vsel_max = 1411000;
+ di->vsel_step = 12826;
+ break;
+ default:
+ dev_err(di->dev,
+ "Chip ID[%d]\n not supported!\n", di->chip_id);
+ return -EINVAL;
+ }
+ /* Init slew rate */
+ if (pdata->slew_rate & 0x7)
+ di->slew_rate = pdata->slew_rate;
+ else
+ di->slew_rate = FAN53555_SLEW_RATE_64MV;
+ reg = FAN53555_CONTROL;
+ data = di->slew_rate << CTL_SLEW_SHIFT;
+ mask = CTL_SLEW_MASK;
+ return regmap_update_bits(di->regmap, reg, mask, data);
+}
+
+static int fan53555_regulator_register(struct fan53555_device_info *di,
+ struct regulator_config *config)
+{
+ struct regulator_desc *rdesc = &di->desc;
+
+ rdesc->name = "fan53555-reg";
+ rdesc->ops = &fan53555_regulator_ops;
+ rdesc->type = REGULATOR_VOLTAGE;
+ rdesc->n_voltages = FAN53555_NVOLTAGES;
+ rdesc->enable_reg = di->vol_reg;
+ rdesc->enable_mask = VSEL_BUCK_EN;
+ rdesc->min_uV = di->vsel_min;
+ rdesc->uV_step = di->vsel_step;
+ rdesc->vsel_reg = di->vol_reg;
+ rdesc->vsel_mask = VSEL_NSEL_MASK;
+ rdesc->owner = THIS_MODULE;
+
+ di->rdev = regulator_register(&di->desc, config);
+ if (IS_ERR(di->rdev))
+ return PTR_ERR(di->rdev);
+ return 0;
+
+}
+
+static struct regmap_config fan53555_regmap_config = {
+ .reg_bits = 8,
+ .val_bits = 8,
+};
+
+static int __devinit fan53555_regulator_probe(struct i2c_client *client,
+ const struct i2c_device_id *id)
+{
+ struct fan53555_device_info *di;
+ struct fan53555_platform_data *pdata;
+ struct regulator_config config = { };
+ unsigned int val;
+ int ret;
+
+ pdata = client->dev.platform_data;
+ if (!pdata || !pdata->regulator) {
+ dev_err(&client->dev, "Platform data not found!\n");
+ return -ENODEV;
+ }
+
+ di = devm_kzalloc(&client->dev, sizeof(struct fan53555_device_info),
+ GFP_KERNEL);
+ if (!di) {
+ dev_err(&client->dev, "Failed to allocate device info data!\n");
+ return -ENOMEM;
+ }
+ di->regmap = devm_regmap_init_i2c(client, &fan53555_regmap_config);
+ if (IS_ERR(di->regmap)) {
+ dev_err(&client->dev, "Failed to allocate regmap!\n");
+ return PTR_ERR(di->regmap);
+ }
+ di->dev = &client->dev;
+ di->regulator = pdata->regulator;
+ i2c_set_clientdata(client, di);
+ /* Get chip ID */
+ ret = regmap_read(di->regmap, FAN53555_ID1, &val);
+ if (ret < 0) {
+ dev_err(&client->dev, "Failed to get chip ID!\n");
+ return -ENODEV;
+ }
+ di->chip_id = val & DIE_ID;
+ /* Get chip revision */
+ ret = regmap_read(di->regmap, FAN53555_ID2, &val);
+ if (ret < 0) {
+ dev_err(&client->dev, "Failed to get chip Rev!\n");
+ return -ENODEV;
+ }
+ di->chip_rev = val & DIE_REV;
+ dev_info(&client->dev, "FAN53555 Option[%d] Rev[%d] Detected!\n",
+ di->chip_id, di->chip_rev);
+ /* Device init */
+ ret = fan53555_device_setup(di, pdata);
+ if (ret < 0) {
+ dev_err(&client->dev, "Failed to setup device!\n");
+ return ret;
+ }
+ /* Register regulator */
+ config.dev = di->dev;
+ config.init_data = di->regulator;
+ config.regmap = di->regmap;
+ config.driver_data = di;
+ ret = fan53555_regulator_register(di, &config);
+ if (ret < 0)
+ dev_err(&client->dev, "Failed to register regulator!\n");
+ return ret;
+
+}
+
+static int __devexit fan53555_regulator_remove(struct i2c_client *client)
+{
+ struct fan53555_device_info *di = i2c_get_clientdata(client);
+
+ regulator_unregister(di->rdev);
+ return 0;
+}
+
+static const struct i2c_device_id fan53555_id[] = {
+ {"fan53555", -1},
+ { },
+};
+
+static struct i2c_driver fan53555_regulator_driver = {
+ .driver = {
+ .name = "fan53555-regulator",
+ },
+ .probe = fan53555_regulator_probe,
+ .remove = __devexit_p(fan53555_regulator_remove),
+ .id_table = fan53555_id,
+};
+
+module_i2c_driver(fan53555_regulator_driver);
+
+MODULE_AUTHOR("Yunfan Zhang <yfzhang@marvell.com>");
+MODULE_DESCRIPTION("FAN53555 regulator driver");
+MODULE_LICENSE("GPL v2");