drivers/mfd/max77686.c

   1 /*
   2  * max77686.c - mfd core driver for the Maxim 77686
   3  *
   4  * Copyright (C) 2012 Samsung Electronics
   5  * Chiwoong Byun <woong.byun@smasung.com>
   6  * Jonghwa Lee <jonghwa3.lee@samsung.com>
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; either version 2 of the License, or
  11  * (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program; if not, write to the Free Software
  20  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  21  *
  22  * This driver is based on max8997.c
  23  */
  24
  25 #include <linux/export.h>
  26 #include <linux/slab.h>
  27 #include <linux/i2c.h>
  28 #include <linux/pm_runtime.h>
  29 #include <linux/module.h>
  30 #include <linux/mutex.h>
  31 #include <linux/mfd/core.h>
  32 #include <linux/mfd/max77686.h>
  33 #include <linux/mfd/max77686-private.h>
  34 #include <linux/err.h>
  35
  36 #define I2C_ADDR_RTC    (0x0C >> 1)
  37
  38 static struct mfd_cell max77686_devs[] = {
  39         { .name = "max77686-pmic", },
  40         { .name = "max77686-rtc", },
  41 };
  42
  43 static struct regmap_config max77686_regmap_config = {
  44         .reg_bits = 8,
  45         .val_bits = 8,
  46 };
  47
  48 static int max77686_i2c_probe(struct i2c_client *i2c,
  49                               const struct i2c_device_id *id)
  50 {
  51         struct max77686_dev *max77686;
  52         struct max77686_platform_data *pdata = i2c->dev.platform_data;
  53         unsigned int data;
  54         int ret = 0;
  55
  56         max77686 = kzalloc(sizeof(struct max77686_dev), GFP_KERNEL);
  57         if (max77686 == NULL)
  58                 return -ENOMEM;
  59
  60         max77686->regmap = regmap_init_i2c(i2c, &max77686_regmap_config);
  61         if (IS_ERR(max77686->regmap)) {
  62                 ret = PTR_ERR(max77686->regmap);
  63                 dev_err(max77686->dev, "Failed to allocate register map: %d\n",
  64                                 ret);
  65                 kfree(max77686);
  66                 return ret;
  67         }
  68
  69         i2c_set_clientdata(i2c, max77686);
  70         max77686->dev = &i2c->dev;
  71         max77686->i2c = i2c;
  72         max77686->type = id->driver_data;
  73
  74         if (!pdata) {
  75                 ret = -EIO;
  76                 goto err;
  77         }
  78
  79         max77686->wakeup = pdata->wakeup;
  80         max77686->irq_gpio = pdata->irq_gpio;
  81
  82         mutex_init(&max77686->iolock);
  83
  84         if (regmap_read(max77686->regmap,
  85                          MAX77686_REG_DEVICE_ID, &data) < 0) {
  86                 dev_err(max77686->dev,
  87                         "device not found on this channel (this is not an error)\n");
  88                 ret = -ENODEV;
  89                 goto err;
  90         } else
  91                 dev_info(max77686->dev, "device found\n");
  92
  93         max77686->rtc = i2c_new_dummy(i2c->adapter, I2C_ADDR_RTC);
  94         i2c_set_clientdata(max77686->rtc, max77686);
  95
  96         max77686_irq_init(max77686);
  97
  98         ret = mfd_add_devices(max77686->dev, -1, max77686_devs,
  99                               ARRAY_SIZE(max77686_devs), NULL, 0);
 100
 101         if (ret < 0)
 102                 goto err_mfd;
 103
 104         return ret;
 105
 106 err_mfd:
 107         mfd_remove_devices(max77686->dev);
 108         i2c_unregister_device(max77686->rtc);
 109 err:
 110         kfree(max77686);
 111         return ret;
 112 }
 113
 114 static int max77686_i2c_remove(struct i2c_client *i2c)
 115 {
 116         struct max77686_dev *max77686 = i2c_get_clientdata(i2c);
 117
 118         mfd_remove_devices(max77686->dev);
 119         i2c_unregister_device(max77686->rtc);
 120         kfree(max77686);
 121
 122         return 0;
 123 }
 124
 125 static const struct i2c_device_id max77686_i2c_id[] = {
 126         { "max77686", TYPE_MAX77686 },
 127         { }
 128 };
 129 MODULE_DEVICE_TABLE(i2c, max77686_i2c_id);
 130
 131 static struct i2c_driver max77686_i2c_driver = {
 132         .driver = {
 133                    .name = "max77686",
 134                    .owner = THIS_MODULE,
 135         },
 136         .probe = max77686_i2c_probe,
 137         .remove = max77686_i2c_remove,
 138         .id_table = max77686_i2c_id,
 139 };
 140
 141 static int __init max77686_i2c_init(void)
 142 {
 143         return i2c_add_driver(&max77686_i2c_driver);
 144 }
 145 /* init early so consumer devices can complete system boot */
 146 subsys_initcall(max77686_i2c_init);
 147
 148 static void __exit max77686_i2c_exit(void)
 149 {
 150         i2c_del_driver(&max77686_i2c_driver);
 151 }
 152 module_exit(max77686_i2c_exit);
 153
 154 MODULE_DESCRIPTION("MAXIM 77686 multi-function core driver");
 155 MODULE_AUTHOR("Chiwoong Byun <woong.byun@samsung.com>");
 156 MODULE_LICENSE("GPL");