root/drivers/regulator/tps6524x-regulator.c
/*
 * Regulator driver for TPS6524x PMIC
 *
 * Copyright (C) 2010 Texas Instruments
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation version 2.
 *
 * This program is distributed "as is" WITHOUT ANY WARRANTY of any kind,
 * whether express or implied; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details.
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/err.h>
#include <linux/errno.h>
#include <linux/slab.h>
#include <linux/spi/spi.h>
#include <linux/regulator/driver.h>
#include <linux/regulator/machine.h>

#define REG_LDO_SET             0x0
#define LDO_ILIM_MASK           1       /* 0 = 400-800, 1 = 900-1500 */
#define LDO_VSEL_MASK           0x0f
#define LDO2_ILIM_SHIFT         12
#define LDO2_VSEL_SHIFT         4
#define LDO1_ILIM_SHIFT         8
#define LDO1_VSEL_SHIFT         0

#define REG_BLOCK_EN            0x1
#define BLOCK_MASK              1
#define BLOCK_LDO1_SHIFT        0
#define BLOCK_LDO2_SHIFT        1
#define BLOCK_LCD_SHIFT         2
#define BLOCK_USB_SHIFT         3

#define REG_DCDC_SET            0x2
#define DCDC_VDCDC_MASK         0x1f
#define DCDC_VDCDC1_SHIFT       0
#define DCDC_VDCDC2_SHIFT       5
#define DCDC_VDCDC3_SHIFT       10

#define REG_DCDC_EN             0x3
#define DCDCDCDC_EN_MASK        0x1
#define DCDCDCDC1_EN_SHIFT      0
#define DCDCDCDC1_PG_MSK        BIT(1)
#define DCDCDCDC2_EN_SHIFT      2
#define DCDCDCDC2_PG_MSK        BIT(3)
#define DCDCDCDC3_EN_SHIFT      4
#define DCDCDCDC3_PG_MSK        BIT(5)

#define REG_USB                 0x4
#define USB_ILIM_SHIFT          0
#define USB_ILIM_MASK           0x3
#define USB_TSD_SHIFT           2
#define USB_TSD_MASK            0x3
#define USB_TWARN_SHIFT         4
#define USB_TWARN_MASK          0x3
#define USB_IWARN_SD            BIT(6)
#define USB_FAST_LOOP           BIT(7)

#define REG_ALARM               0x5
#define ALARM_LDO1              BIT(0)
#define ALARM_DCDC1             BIT(1)
#define ALARM_DCDC2             BIT(2)
#define ALARM_DCDC3             BIT(3)
#define ALARM_LDO2              BIT(4)
#define ALARM_USB_WARN          BIT(5)
#define ALARM_USB_ALARM         BIT(6)
#define ALARM_LCD               BIT(9)
#define ALARM_TEMP_WARM         BIT(10)
#define ALARM_TEMP_HOT          BIT(11)
#define ALARM_NRST              BIT(14)
#define ALARM_POWERUP           BIT(15)

#define REG_INT_ENABLE          0x6
#define INT_LDO1                BIT(0)
#define INT_DCDC1               BIT(1)
#define INT_DCDC2               BIT(2)
#define INT_DCDC3               BIT(3)
#define INT_LDO2                BIT(4)
#define INT_USB_WARN            BIT(5)
#define INT_USB_ALARM           BIT(6)
#define INT_LCD                 BIT(9)
#define INT_TEMP_WARM           BIT(10)
#define INT_TEMP_HOT            BIT(11)
#define INT_GLOBAL_EN           BIT(15)

#define REG_INT_STATUS          0x7
#define STATUS_LDO1             BIT(0)
#define STATUS_DCDC1            BIT(1)
#define STATUS_DCDC2            BIT(2)
#define STATUS_DCDC3            BIT(3)
#define STATUS_LDO2             BIT(4)
#define STATUS_USB_WARN         BIT(5)
#define STATUS_USB_ALARM        BIT(6)
#define STATUS_LCD              BIT(9)
#define STATUS_TEMP_WARM        BIT(10)
#define STATUS_TEMP_HOT         BIT(11)

#define REG_SOFTWARE_RESET      0xb
#define REG_WRITE_ENABLE        0xd
#define REG_REV_ID              0xf

#define N_DCDC                  3
#define N_LDO                   2
#define N_SWITCH                2
#define N_REGULATORS            (N_DCDC + N_LDO + N_SWITCH)

#define CMD_READ(reg)           ((reg) << 6)
#define CMD_WRITE(reg)          (BIT(5) | (reg) << 6)
#define STAT_CLK                BIT(3)
#define STAT_WRITE              BIT(2)
#define STAT_INVALID            BIT(1)
#define STAT_WP                 BIT(0)

struct field {
        int             reg;
        int             shift;
        int             mask;
};

struct supply_info {
        const char      *name;
        int             n_voltages;
        const unsigned int *voltages;
        int             n_ilimsels;
        const unsigned int *ilimsels;
        struct field    enable, voltage, ilimsel;
};

struct tps6524x {
        struct device           *dev;
        struct spi_device       *spi;
        struct mutex            lock;
        struct regulator_desc   desc[N_REGULATORS];
};

static int __read_reg(struct tps6524x *hw, int reg)
{
        int error = 0;
        u16 cmd = CMD_READ(reg), in;
        u8 status;
        struct spi_message m;
        struct spi_transfer t[3];

        spi_message_init(&m);
        memset(t, 0, sizeof(t));

        t[0].tx_buf = &cmd;
        t[0].len = 2;
        t[0].bits_per_word = 12;
        spi_message_add_tail(&t[0], &m);

        t[1].rx_buf = &in;
        t[1].len = 2;
        t[1].bits_per_word = 16;
        spi_message_add_tail(&t[1], &m);

        t[2].rx_buf = &status;
        t[2].len = 1;
        t[2].bits_per_word = 4;
        spi_message_add_tail(&t[2], &m);

        error = spi_sync(hw->spi, &m);
        if (error < 0)
                return error;

        dev_dbg(hw->dev, "read reg %d, data %x, status %x\n",
                reg, in, status);

        if (!(status & STAT_CLK) || (status & STAT_WRITE))
                return -EIO;

        if (status & STAT_INVALID)
                return -EINVAL;

        return in;
}

static int read_reg(struct tps6524x *hw, int reg)
{
        int ret;

        mutex_lock(&hw->lock);
        ret = __read_reg(hw, reg);
        mutex_unlock(&hw->lock);

        return ret;
}

static int __write_reg(struct tps6524x *hw, int reg, int val)
{
        int error = 0;
        u16 cmd = CMD_WRITE(reg), out = val;
        u8 status;
        struct spi_message m;
        struct spi_transfer t[3];

        spi_message_init(&m);
        memset(t, 0, sizeof(t));

        t[0].tx_buf = &cmd;
        t[0].len = 2;
        t[0].bits_per_word = 12;
        spi_message_add_tail(&t[0], &m);

        t[1].tx_buf = &out;
        t[1].len = 2;
        t[1].bits_per_word = 16;
        spi_message_add_tail(&t[1], &m);

        t[2].rx_buf = &status;
        t[2].len = 1;
        t[2].bits_per_word = 4;
        spi_message_add_tail(&t[2], &m);

        error = spi_sync(hw->spi, &m);
        if (error < 0)
                return error;

        dev_dbg(hw->dev, "wrote reg %d, data %x, status %x\n",
                reg, out, status);

        if (!(status & STAT_CLK) || !(status & STAT_WRITE))
                return -EIO;

        if (status & (STAT_INVALID | STAT_WP))
                return -EINVAL;

        return error;
}

static int __rmw_reg(struct tps6524x *hw, int reg, int mask, int val)
{
        int ret;

        ret = __read_reg(hw, reg);
        if (ret < 0)
                return ret;

        ret &= ~mask;
        ret |= val;

        ret = __write_reg(hw, reg, ret);

        return (ret < 0) ? ret : 0;
}

static int rmw_protect(struct tps6524x *hw, int reg, int mask, int val)
{
        int ret;

        mutex_lock(&hw->lock);

        ret = __write_reg(hw, REG_WRITE_ENABLE, 1);
        if (ret) {
                dev_err(hw->dev, "failed to set write enable\n");
                goto error;
        }

        ret = __rmw_reg(hw, reg, mask, val);
        if (ret)
                dev_err(hw->dev, "failed to rmw register %d\n", reg);

        ret = __write_reg(hw, REG_WRITE_ENABLE, 0);
        if (ret) {
                dev_err(hw->dev, "failed to clear write enable\n");
                goto error;
        }

error:
        mutex_unlock(&hw->lock);

        return ret;
}

static int read_field(struct tps6524x *hw, const struct field *field)
{
        int tmp;

        tmp = read_reg(hw, field->reg);
        if (tmp < 0)
                return tmp;

        return (tmp >> field->shift) & field->mask;
}

static int write_field(struct tps6524x *hw, const struct field *field,
                       int val)
{
        if (val & ~field->mask)
                return -EOVERFLOW;

        return rmw_protect(hw, field->reg,
                                    field->mask << field->shift,
                                    val << field->shift);
}

static const unsigned int dcdc1_voltages[] = {
         800000,  825000,  850000,  875000,
         900000,  925000,  950000,  975000,
        1000000, 1025000, 1050000, 1075000,
        1100000, 1125000, 1150000, 1175000,
        1200000, 1225000, 1250000, 1275000,
        1300000, 1325000, 1350000, 1375000,
        1400000, 1425000, 1450000, 1475000,
        1500000, 1525000, 1550000, 1575000,
};

static const unsigned int dcdc2_voltages[] = {
        1400000, 1450000, 1500000, 1550000,
        1600000, 1650000, 1700000, 1750000,
        1800000, 1850000, 1900000, 1950000,
        2000000, 2050000, 2100000, 2150000,
        2200000, 2250000, 2300000, 2350000,
        2400000, 2450000, 2500000, 2550000,
        2600000, 2650000, 2700000, 2750000,
        2800000, 2850000, 2900000, 2950000,
};

static const unsigned int dcdc3_voltages[] = {
        2400000, 2450000, 2500000, 2550000, 2600000,
        2650000, 2700000, 2750000, 2800000, 2850000,
        2900000, 2950000, 3000000, 3050000, 3100000,
        3150000, 3200000, 3250000, 3300000, 3350000,
        3400000, 3450000, 3500000, 3550000, 3600000,
};

static const unsigned int ldo1_voltages[] = {
        4300000, 4350000, 4400000, 4450000,
        4500000, 4550000, 4600000, 4650000,
        4700000, 4750000, 4800000, 4850000,
        4900000, 4950000, 5000000, 5050000,
};

static const unsigned int ldo2_voltages[] = {
        1100000, 1150000, 1200000, 1250000,
        1300000, 1700000, 1750000, 1800000,
        1850000, 1900000, 3150000, 3200000,
        3250000, 3300000, 3350000, 3400000,
};

static const unsigned int fixed_5000000_voltage[] = {
        5000000
};

static const unsigned int ldo_ilimsel[] = {
        400000, 1500000
};

static const unsigned int usb_ilimsel[] = {
        200000, 400000, 800000, 1000000
};

static const unsigned int fixed_2400000_ilimsel[] = {
        2400000
};

static const unsigned int fixed_1200000_ilimsel[] = {
        1200000
};

static const unsigned int fixed_400000_ilimsel[] = {
        400000
};

#define __MK_FIELD(_reg, _mask, _shift) \
        { .reg = (_reg), .mask = (_mask), .shift = (_shift), }

static const struct supply_info supply_info[N_REGULATORS] = {
        {
                .name           = "DCDC1",
                .n_voltages     = ARRAY_SIZE(dcdc1_voltages),
                .voltages       = dcdc1_voltages,
                .n_ilimsels     = ARRAY_SIZE(fixed_2400000_ilimsel),
                .ilimsels       = fixed_2400000_ilimsel,
                .enable         = __MK_FIELD(REG_DCDC_EN, DCDCDCDC_EN_MASK,
                                             DCDCDCDC1_EN_SHIFT),
                .voltage        = __MK_FIELD(REG_DCDC_SET, DCDC_VDCDC_MASK,
                                             DCDC_VDCDC1_SHIFT),
        },
        {
                .name           = "DCDC2",
                .n_voltages     = ARRAY_SIZE(dcdc2_voltages),
                .voltages       = dcdc2_voltages,
                .n_ilimsels     = ARRAY_SIZE(fixed_1200000_ilimsel),
                .ilimsels       = fixed_1200000_ilimsel,
                .enable         = __MK_FIELD(REG_DCDC_EN, DCDCDCDC_EN_MASK,
                                             DCDCDCDC2_EN_SHIFT),
                .voltage        = __MK_FIELD(REG_DCDC_SET, DCDC_VDCDC_MASK,
                                             DCDC_VDCDC2_SHIFT),
        },
        {
                .name           = "DCDC3",
                .n_voltages     = ARRAY_SIZE(dcdc3_voltages),
                .voltages       = dcdc3_voltages,
                .n_ilimsels     = ARRAY_SIZE(fixed_1200000_ilimsel),
                .ilimsels       = fixed_1200000_ilimsel,
                .enable         = __MK_FIELD(REG_DCDC_EN, DCDCDCDC_EN_MASK,
                                        DCDCDCDC3_EN_SHIFT),
                .voltage        = __MK_FIELD(REG_DCDC_SET, DCDC_VDCDC_MASK,
                                             DCDC_VDCDC3_SHIFT),
        },
        {
                .name           = "LDO1",
                .n_voltages     = ARRAY_SIZE(ldo1_voltages),
                .voltages       = ldo1_voltages,
                .n_ilimsels     = ARRAY_SIZE(ldo_ilimsel),
                .ilimsels       = ldo_ilimsel,
                .enable         = __MK_FIELD(REG_BLOCK_EN, BLOCK_MASK,
                                             BLOCK_LDO1_SHIFT),
                .voltage        = __MK_FIELD(REG_LDO_SET, LDO_VSEL_MASK,
                                             LDO1_VSEL_SHIFT),
                .ilimsel        = __MK_FIELD(REG_LDO_SET, LDO_ILIM_MASK,
                                             LDO1_ILIM_SHIFT),
        },
        {
                .name           = "LDO2",
                .n_voltages     = ARRAY_SIZE(ldo2_voltages),
                .voltages       = ldo2_voltages,
                .n_ilimsels     = ARRAY_SIZE(ldo_ilimsel),
                .ilimsels       = ldo_ilimsel,
                .enable         = __MK_FIELD(REG_BLOCK_EN, BLOCK_MASK,
                                             BLOCK_LDO2_SHIFT),
                .voltage        = __MK_FIELD(REG_LDO_SET, LDO_VSEL_MASK,
                                             LDO2_VSEL_SHIFT),
                .ilimsel        = __MK_FIELD(REG_LDO_SET, LDO_ILIM_MASK,
                                             LDO2_ILIM_SHIFT),
        },
        {
                .name           = "USB",
                .n_voltages     = ARRAY_SIZE(fixed_5000000_voltage),
                .voltages       = fixed_5000000_voltage,
                .n_ilimsels     = ARRAY_SIZE(usb_ilimsel),
                .ilimsels       = usb_ilimsel,
                .enable         = __MK_FIELD(REG_BLOCK_EN, BLOCK_MASK,
                                             BLOCK_USB_SHIFT),
                .ilimsel        = __MK_FIELD(REG_USB, USB_ILIM_MASK,
                                             USB_ILIM_SHIFT),
        },
        {
                .name           = "LCD",
                .n_voltages     = ARRAY_SIZE(fixed_5000000_voltage),
                .voltages       = fixed_5000000_voltage,
                .n_ilimsels     = ARRAY_SIZE(fixed_400000_ilimsel),
                .ilimsels       = fixed_400000_ilimsel,
                .enable         = __MK_FIELD(REG_BLOCK_EN, BLOCK_MASK,
                                             BLOCK_LCD_SHIFT),
        },
};

static int set_voltage_sel(struct regulator_dev *rdev, unsigned selector)
{
        const struct supply_info *info;
        struct tps6524x *hw;

        hw      = rdev_get_drvdata(rdev);
        info    = &supply_info[rdev_get_id(rdev)];

        if (rdev->desc->n_voltages == 1)
                return -EINVAL;

        return write_field(hw, &info->voltage, selector);
}

static int get_voltage_sel(struct regulator_dev *rdev)
{
        const struct supply_info *info;
        struct tps6524x *hw;
        int ret;

        hw      = rdev_get_drvdata(rdev);
        info    = &supply_info[rdev_get_id(rdev)];

        if (rdev->desc->n_voltages == 1)
                return 0;

        ret = read_field(hw, &info->voltage);
        if (ret < 0)
                return ret;
        if (WARN_ON(ret >= info->n_voltages))
                return -EIO;

        return ret;
}

static int set_current_limit(struct regulator_dev *rdev, int min_uA,
                             int max_uA)
{
        const struct supply_info *info;
        struct tps6524x *hw;
        int i;

        hw      = rdev_get_drvdata(rdev);
        info    = &supply_info[rdev_get_id(rdev)];

        if (info->n_ilimsels == 1)
                return -EINVAL;

        for (i = info->n_ilimsels - 1; i >= 0; i--) {
                if (min_uA <= info->ilimsels[i] &&
                    max_uA >= info->ilimsels[i])
                        return write_field(hw, &info->ilimsel, i);
        }

        return -EINVAL;
}

static int get_current_limit(struct regulator_dev *rdev)
{
        const struct supply_info *info;
        struct tps6524x *hw;
        int ret;

        hw      = rdev_get_drvdata(rdev);
        info    = &supply_info[rdev_get_id(rdev)];

        if (info->n_ilimsels == 1)
                return info->ilimsels[0];

        ret = read_field(hw, &info->ilimsel);
        if (ret < 0)
                return ret;
        if (WARN_ON(ret >= info->n_ilimsels))
                return -EIO;

        return info->ilimsels[ret];
}

static int enable_supply(struct regulator_dev *rdev)
{
        const struct supply_info *info;
        struct tps6524x *hw;

        hw      = rdev_get_drvdata(rdev);
        info    = &supply_info[rdev_get_id(rdev)];

        return write_field(hw, &info->enable, 1);
}

static int disable_supply(struct regulator_dev *rdev)
{
        const struct supply_info *info;
        struct tps6524x *hw;

        hw      = rdev_get_drvdata(rdev);
        info    = &supply_info[rdev_get_id(rdev)];

        return write_field(hw, &info->enable, 0);
}

static int is_supply_enabled(struct regulator_dev *rdev)
{
        const struct supply_info *info;
        struct tps6524x *hw;

        hw      = rdev_get_drvdata(rdev);
        info    = &supply_info[rdev_get_id(rdev)];

        return read_field(hw, &info->enable);
}

static const struct regulator_ops regulator_ops = {
        .is_enabled             = is_supply_enabled,
        .enable                 = enable_supply,
        .disable                = disable_supply,
        .get_voltage_sel        = get_voltage_sel,
        .set_voltage_sel        = set_voltage_sel,
        .list_voltage           = regulator_list_voltage_table,
        .map_voltage            = regulator_map_voltage_ascend,
        .set_current_limit      = set_current_limit,
        .get_current_limit      = get_current_limit,
};

static int pmic_probe(struct spi_device *spi)
{
        struct tps6524x *hw;
        struct device *dev = &spi->dev;
        const struct supply_info *info = supply_info;
        struct regulator_init_data *init_data;
        struct regulator_config config = { };
        struct regulator_dev *rdev;
        int i;

        init_data = dev_get_platdata(dev);
        if (!init_data) {
                dev_err(dev, "could not find regulator platform data\n");
                return -EINVAL;
        }

        hw = devm_kzalloc(&spi->dev, sizeof(struct tps6524x), GFP_KERNEL);
        if (!hw)
                return -ENOMEM;

        spi_set_drvdata(spi, hw);

        hw->dev = dev;
        hw->spi = spi;
        mutex_init(&hw->lock);

        for (i = 0; i < N_REGULATORS; i++, info++, init_data++) {
                hw->desc[i].name        = info->name;
                hw->desc[i].id          = i;
                hw->desc[i].n_voltages  = info->n_voltages;
                hw->desc[i].volt_table  = info->voltages;
                hw->desc[i].ops         = &regulator_ops;
                hw->desc[i].type        = REGULATOR_VOLTAGE;
                hw->desc[i].owner       = THIS_MODULE;

                config.dev = dev;
                config.init_data = init_data;
                config.driver_data = hw;

                rdev = devm_regulator_register(dev, &hw->desc[i], &config);
                if (IS_ERR(rdev))
                        return PTR_ERR(rdev);
        }

        return 0;
}

static struct spi_driver pmic_driver = {
        .probe          = pmic_probe,
        .driver         = {
                .name   = "tps6524x",
                .probe_type = PROBE_PREFER_ASYNCHRONOUS,
        },
};

module_spi_driver(pmic_driver);

MODULE_DESCRIPTION("TPS6524X PMIC Driver");
MODULE_AUTHOR("Cyril Chemparathy");
MODULE_LICENSE("GPL");
MODULE_ALIAS("spi:tps6524x");