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
  20 static const struct mfd_cell rn5t618_cells[] = {
  21         { .name = "rn5t618-regulator" },
  22         { .name = "rn5t618-wdt" },
  23 };
  24
  25 static 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_ADCCNT3:
  32         case RN5T618_IR_ADC1 ... RN5T618_IR_ADC3:
  33         case RN5T618_IR_GPR:
  34         case RN5T618_IR_GPF:
  35         case RN5T618_MON_IOIN:
  36         case RN5T618_INTMON:
  37                 return true;
  38         default:
  39                 return false;
  40         }
  41 }
  42
  43 static const struct regmap_config rn5t618_regmap_config = {
  44         .reg_bits       = 8,
  45         .val_bits       = 8,
  46         .volatile_reg   = rn5t618_volatile_reg,
  47         .max_register   = RN5T618_MAX_REG,
  48         .cache_type     = REGCACHE_RBTREE,
  49 };
  50
  51 static struct rn5t618 *rn5t618_pm_power_off;
  52
  53 static void rn5t618_power_off(void)
  54 {
  55         /* disable automatic repower-on */
  56         regmap_update_bits(rn5t618_pm_power_off->regmap, RN5T618_REPCNT,
  57                            RN5T618_REPCNT_REPWRON, 0);
  58         /* start power-off sequence */
  59         regmap_update_bits(rn5t618_pm_power_off->regmap, RN5T618_SLPCNT,
  60                            RN5T618_SLPCNT_SWPWROFF, RN5T618_SLPCNT_SWPWROFF);
  61 }
  62
  63 static int rn5t618_i2c_probe(struct i2c_client *i2c,
  64                              const struct i2c_device_id *id)
  65 {
  66         struct rn5t618 *priv;
  67         int ret;
  68
  69         priv = devm_kzalloc(&i2c->dev, sizeof(*priv), GFP_KERNEL);
  70         if (!priv)
  71                 return -ENOMEM;
  72
  73         i2c_set_clientdata(i2c, priv);
  74
  75         priv->regmap = devm_regmap_init_i2c(i2c, &rn5t618_regmap_config);
  76         if (IS_ERR(priv->regmap)) {
  77                 ret = PTR_ERR(priv->regmap);
  78                 dev_err(&i2c->dev, "regmap init failed: %d\n", ret);
  79                 return ret;
  80         }
  81
  82         ret = mfd_add_devices(&i2c->dev, -1, rn5t618_cells,
  83                               ARRAY_SIZE(rn5t618_cells), NULL, 0, NULL);
  84         if (ret) {
  85                 dev_err(&i2c->dev, "failed to add sub-devices: %d\n", ret);
  86                 return ret;
  87         }
  88
  89         if (!pm_power_off) {
  90                 rn5t618_pm_power_off = priv;
  91                 pm_power_off = rn5t618_power_off;
  92         }
  93
  94         return 0;
  95 }
  96
  97 static int rn5t618_i2c_remove(struct i2c_client *i2c)
  98 {
  99         struct rn5t618 *priv = i2c_get_clientdata(i2c);
 100
 101         if (priv == rn5t618_pm_power_off) {
 102                 rn5t618_pm_power_off = NULL;
 103                 pm_power_off = NULL;
 104         }
 105
 106         mfd_remove_devices(&i2c->dev);
 107         return 0;
 108 }
 109
 110 static const struct of_device_id rn5t618_of_match[] = {
 111         { .compatible = "ricoh,rn5t618" },
 112         { }
 113 };
 114 MODULE_DEVICE_TABLE(of, rn5t618_of_match);
 115
 116 static const struct i2c_device_id rn5t618_i2c_id[] = {
 117         { }
 118 };
 119 MODULE_DEVICE_TABLE(i2c, rn5t618_i2c_id);
 120
 121 static struct i2c_driver rn5t618_i2c_driver = {
 122         .driver = {
 123                 .name = "rn5t618",
 124                 .of_match_table = of_match_ptr(rn5t618_of_match),
 125         },
 126         .probe = rn5t618_i2c_probe,
 127         .remove = rn5t618_i2c_remove,
 128         .id_table = rn5t618_i2c_id,
 129 };
 130
 131 module_i2c_driver(rn5t618_i2c_driver);
 132
 133 MODULE_AUTHOR("Beniamino Galvani <b.galvani@gmail.com>");
 134 MODULE_DESCRIPTION("Ricoh RN5T618 MFD driver");
 135 MODULE_LICENSE("GPL v2");