LXR linux/drivers/mfd/rn5t618.c

   1/*
   2 * MFD core driver for Ricoh RN5T618 PMIC
   3 *
   4 * Copyright (C) 2014 Beniamino Galvani <b.galvani@gmail.com>
   5 *
   6 * This program is free software; you can redistribute it and/or
   7 * modify it under the terms of the GNU General Public License
   8 * version 2 as published by the Free Software Foundation.
   9 *
  10 * You should have received a copy of the GNU General Public License
  11 * along with this program. If not, see <http://www.gnu.org/licenses/>.
  12 */
  13
  14#include <linux/i2c.h>
  15#include <linux/mfd/core.h>
  16#include <linux/mfd/rn5t618.h>
  17#include <linux/module.h>
  18#include <linux/regmap.h>
  19
  20static const struct mfd_cell rn5t618_cells[] = {
  21        { .name = "rn5t618-regulator" },
  22        { .name = "rn5t618-wdt" },
  23};
  24
  25static bool rn5t618_volatile_reg(struct device *dev, unsigned int reg)
  26{
  27        switch (reg) {
  28        case RN5T618_WATCHDOGCNT:
  29        case RN5T618_DCIRQ:
  30        case RN5T618_ILIMDATAH ... RN5T618_AIN0DATAL:
  31        case RN5T618_IR_ADC1 ... RN5T618_IR_ADC3:
  32        case RN5T618_IR_GPR:
  33        case RN5T618_IR_GPF:
  34        case RN5T618_MON_IOIN:
  35        case RN5T618_INTMON:
  36                return true;
  37        default:
  38                return false;
  39        }
  40}
  41
  42static const struct regmap_config rn5t618_regmap_config = {
  43        .reg_bits       = 8,
  44        .val_bits       = 8,
  45        .volatile_reg   = rn5t618_volatile_reg,
  46        .max_register   = RN5T618_MAX_REG,
  47        .cache_type     = REGCACHE_RBTREE,
  48};
  49
  50static struct rn5t618 *rn5t618_pm_power_off;
  51
  52static void rn5t618_power_off(void)
  53{
  54        /* disable automatic repower-on */
  55        regmap_update_bits(rn5t618_pm_power_off->regmap, RN5T618_REPCNT,
  56                           RN5T618_REPCNT_REPWRON, 0);
  57        /* start power-off sequence */
  58        regmap_update_bits(rn5t618_pm_power_off->regmap, RN5T618_SLPCNT,
  59                           RN5T618_SLPCNT_SWPWROFF, RN5T618_SLPCNT_SWPWROFF);
  60}
  61
  62static int rn5t618_i2c_probe(struct i2c_client *i2c,
  63                             const struct i2c_device_id *id)
  64{
  65        struct rn5t618 *priv;
  66        int ret;
  67
  68        priv = devm_kzalloc(&i2c->dev, sizeof(*priv), GFP_KERNEL);
  69        if (!priv)
  70                return -ENOMEM;
  71
  72        i2c_set_clientdata(i2c, priv);
  73
  74        priv->regmap = devm_regmap_init_i2c(i2c, &rn5t618_regmap_config);
  75        if (IS_ERR(priv->regmap)) {
  76                ret = PTR_ERR(priv->regmap);
  77                dev_err(&i2c->dev, "regmap init failed: %d\n", ret);
  78                return ret;
  79        }
  80
  81        ret = mfd_add_devices(&i2c->dev, -1, rn5t618_cells,
  82                              ARRAY_SIZE(rn5t618_cells), NULL, 0, NULL);
  83        if (ret) {
  84                dev_err(&i2c->dev, "failed to add sub-devices: %d\n", ret);
  85                return ret;
  86        }
  87
  88        if (!pm_power_off) {
  89                rn5t618_pm_power_off = priv;
  90                pm_power_off = rn5t618_power_off;
  91        }
  92
  93        return 0;
  94}
  95
  96static int rn5t618_i2c_remove(struct i2c_client *i2c)
  97{
  98        struct rn5t618 *priv = i2c_get_clientdata(i2c);
  99
 100        if (priv == rn5t618_pm_power_off) {
 101                rn5t618_pm_power_off = NULL;
 102                pm_power_off = NULL;
 103        }
 104
 105        mfd_remove_devices(&i2c->dev);
 106        return 0;
 107}
 108
 109static const struct of_device_id rn5t618_of_match[] = {
 110        { .compatible = "ricoh,rn5t618" },
 111        { }
 112};
 113MODULE_DEVICE_TABLE(of, rn5t618_of_match);
 114
 115static const struct i2c_device_id rn5t618_i2c_id[] = {
 116        { }
 117};
 118MODULE_DEVICE_TABLE(i2c, rn5t618_i2c_id);
 119
 120static struct i2c_driver rn5t618_i2c_driver = {
 121        .driver = {
 122                .name = "rn5t618",
 123                .of_match_table = of_match_ptr(rn5t618_of_match),
 124        },
 125        .probe = rn5t618_i2c_probe,
 126        .remove = rn5t618_i2c_remove,
 127        .id_table = rn5t618_i2c_id,
 128};
 129
 130module_i2c_driver(rn5t618_i2c_driver);
 131
 132MODULE_AUTHOR("Beniamino Galvani <b.galvani@gmail.com>");
 133MODULE_DESCRIPTION("Ricoh RN5T618 MFD driver");
 134MODULE_LICENSE("GPL v2");
 135