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_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
  42 static 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
  50 static struct rn5t618 *rn5t618_pm_power_off;
  51
  52 static 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
  62 static 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
  96 static 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
 109 static const struct of_device_id rn5t618_of_match[] = {
 110         { .compatible = "ricoh,rn5t618" },
 111         { }
 112 };
 113 MODULE_DEVICE_TABLE(of, rn5t618_of_match);
 114
 115 static const struct i2c_device_id rn5t618_i2c_id[] = {
 116         { }
 117 };
 118 MODULE_DEVICE_TABLE(i2c, rn5t618_i2c_id);
 119
 120 static 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
 130 module_i2c_driver(rn5t618_i2c_driver);
 131
 132 MODULE_AUTHOR("Beniamino Galvani <b.galvani@gmail.com>");
 133 MODULE_DESCRIPTION("Ricoh RN5T618 MFD driver");
 134 MODULE_LICENSE("GPL v2");