aat2870-regulator.c

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/*
 * linux/drivers/regulator/aat2870-regulator.c
 *
 * Copyright (c) 2011, NVIDIA Corporation.
 * Author: Jin Park <[email protected]>
 *
 * 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.
 *
 * This program 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
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
 * 02110-1301 USA
 */

#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/err.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/platform_device.h>
#include <linux/regulator/driver.h>
#include <linux/regulator/machine.h>
#include <linux/mfd/aat2870.h>

struct aat2870_regulator {
    struct aat2870_data *aat2870;
    struct regulator_desc desc;

    u8 enable_addr;
    u8 enable_shift;
    u8 enable_mask;

    u8 voltage_addr;
    u8 voltage_shift;
    u8 voltage_mask;
};

static int aat2870_ldo_set_voltage_sel(struct regulator_dev *rdev,
                       unsigned selector)
{
    struct aat2870_regulator *ri = rdev_get_drvdata(rdev);
    struct aat2870_data *aat2870 = ri->aat2870;

    return aat2870->update(aat2870, ri->voltage_addr, ri->voltage_mask,
                   selector << ri->voltage_shift);
}

static int aat2870_ldo_get_voltage_sel(struct regulator_dev *rdev)
{
    struct aat2870_regulator *ri = rdev_get_drvdata(rdev);
    struct aat2870_data *aat2870 = ri->aat2870;
    u8 val;
    int ret;

    ret = aat2870->read(aat2870, ri->voltage_addr, &val);
    if (ret)
        return ret;

    return (val & ri->voltage_mask) >> ri->voltage_shift;
}

static int aat2870_ldo_enable(struct regulator_dev *rdev)
{
    struct aat2870_regulator *ri = rdev_get_drvdata(rdev);
    struct aat2870_data *aat2870 = ri->aat2870;

    return aat2870->update(aat2870, ri->enable_addr, ri->enable_mask,
                   ri->enable_mask);
}

static int aat2870_ldo_disable(struct regulator_dev *rdev)
{
    struct aat2870_regulator *ri = rdev_get_drvdata(rdev);
    struct aat2870_data *aat2870 = ri->aat2870;

    return aat2870->update(aat2870, ri->enable_addr, ri->enable_mask, 0);
}

static int aat2870_ldo_is_enabled(struct regulator_dev *rdev)
{
    struct aat2870_regulator *ri = rdev_get_drvdata(rdev);
    struct aat2870_data *aat2870 = ri->aat2870;
    u8 val;
    int ret;

    ret = aat2870->read(aat2870, ri->enable_addr, &val);
    if (ret)
        return ret;

    return val & ri->enable_mask ? 1 : 0;
}

static struct regulator_ops aat2870_ldo_ops = {
    .list_voltage = regulator_list_voltage_table,
    .set_voltage_sel = aat2870_ldo_set_voltage_sel,
    .get_voltage_sel = aat2870_ldo_get_voltage_sel,
    .enable = aat2870_ldo_enable,
    .disable = aat2870_ldo_disable,
    .is_enabled = aat2870_ldo_is_enabled,
};

static const unsigned int aat2870_ldo_voltages[] = {
    1200000, 1300000, 1500000, 1600000,
    1800000, 2000000, 2200000, 2500000,
    2600000, 2700000, 2800000, 2900000,
    3000000, 3100000, 3200000, 3300000,
};

#define AAT2870_LDO(ids)                \
    {                       \
        .desc = {               \
            .name = #ids,           \
            .id = AAT2870_ID_##ids,     \
            .n_voltages = ARRAY_SIZE(aat2870_ldo_voltages), \
            .volt_table = aat2870_ldo_voltages, \
            .ops = &aat2870_ldo_ops,    \
            .type = REGULATOR_VOLTAGE,  \
            .owner = THIS_MODULE,       \
        },                  \
    }

static struct aat2870_regulator aat2870_regulators[] = {
    AAT2870_LDO(LDOA),
    AAT2870_LDO(LDOB),
    AAT2870_LDO(LDOC),
    AAT2870_LDO(LDOD),
};

static struct aat2870_regulator *aat2870_get_regulator(int id)
{
    struct aat2870_regulator *ri = NULL;
    int i;

    for (i = 0; i < ARRAY_SIZE(aat2870_regulators); i++) {
        ri = &aat2870_regulators[i];
        if (ri->desc.id == id)
            break;
    }

    if (i == ARRAY_SIZE(aat2870_regulators))
        return NULL;

    ri->enable_addr = AAT2870_LDO_EN;
    ri->enable_shift = id - AAT2870_ID_LDOA;
    ri->enable_mask = 0x1 << ri->enable_shift;

    ri->voltage_addr = (id - AAT2870_ID_LDOA) / 2 ?
               AAT2870_LDO_CD : AAT2870_LDO_AB;
    ri->voltage_shift = (id - AAT2870_ID_LDOA) % 2 ? 0 : 4;
    ri->voltage_mask = 0xF << ri->voltage_shift;

    return ri;
}

static int aat2870_regulator_probe(struct platform_device *pdev)
{
    struct aat2870_regulator *ri;
    struct regulator_config config = { };
    struct regulator_dev *rdev;

    ri = aat2870_get_regulator(pdev->id);
    if (!ri) {
        dev_err(&pdev->dev, "Invalid device ID, %d\n", pdev->id);
        return -EINVAL;
    }
    ri->aat2870 = dev_get_drvdata(pdev->dev.parent);

    config.dev = &pdev->dev;
    config.driver_data = ri;
    config.init_data = pdev->dev.platform_data;

    rdev = regulator_register(&ri->desc, &config);
    if (IS_ERR(rdev)) {
        dev_err(&pdev->dev, "Failed to register regulator %s\n",
            ri->desc.name);
        return PTR_ERR(rdev);
    }
    platform_set_drvdata(pdev, rdev);

    return 0;
}

static int __devexit aat2870_regulator_remove(struct platform_device *pdev)
{
    struct regulator_dev *rdev = platform_get_drvdata(pdev);

    regulator_unregister(rdev);
    return 0;
}

static struct platform_driver aat2870_regulator_driver = {
    .driver = {
        .name   = "aat2870-regulator",
        .owner  = THIS_MODULE,
    },
    .probe  = aat2870_regulator_probe,
    .remove = __devexit_p(aat2870_regulator_remove),
};

static int __init aat2870_regulator_init(void)
{
    return platform_driver_register(&aat2870_regulator_driver);
}
subsys_initcall(aat2870_regulator_init);

static void __exit aat2870_regulator_exit(void)
{
    platform_driver_unregister(&aat2870_regulator_driver);
}
module_exit(aat2870_regulator_exit);

MODULE_DESCRIPTION("AnalogicTech AAT2870 Regulator");
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Jin Park <[email protected]>");
MODULE_ALIAS("platform:aat2870-regulator");