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max77686.c
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1 /*
2  * max77686.c - mfd core driver for the Maxim 77686
3  *
4  * Copyright (C) 2012 Samsung Electronics
5  * Chiwoong Byun <[email protected]>
6  * Jonghwa Lee <[email protected]>
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/mfd/core.h>
31 #include <linux/mfd/max77686.h>
33 #include <linux/err.h>
34 
35 #define I2C_ADDR_RTC (0x0C >> 1)
36 
37 static struct mfd_cell max77686_devs[] = {
38  { .name = "max77686-pmic", },
39  { .name = "max77686-rtc", },
40 };
41 
42 static struct regmap_config max77686_regmap_config = {
43  .reg_bits = 8,
44  .val_bits = 8,
45 };
46 
47 #ifdef CONFIG_OF
48 static struct of_device_id __devinitdata max77686_pmic_dt_match[] = {
49  {.compatible = "maxim,max77686", .data = 0},
50  {},
51 };
52 
53 static struct max77686_platform_data *max77686_i2c_parse_dt_pdata(struct device
54  *dev)
55 {
56  struct max77686_platform_data *pd;
57 
58  pd = devm_kzalloc(dev, sizeof(*pd), GFP_KERNEL);
59  if (!pd) {
60  dev_err(dev, "could not allocate memory for pdata\n");
61  return NULL;
62  }
63 
64  dev->platform_data = pd;
65  return pd;
66 }
67 #else
68 static struct max77686_platform_data *max77686_i2c_parse_dt_pdata(struct device
69  *dev)
70 {
71  return 0;
72 }
73 #endif
74 
75 static int max77686_i2c_probe(struct i2c_client *i2c,
76  const struct i2c_device_id *id)
77 {
78  struct max77686_dev *max77686 = NULL;
79  struct max77686_platform_data *pdata = i2c->dev.platform_data;
80  unsigned int data;
81  int ret = 0;
82 
83  if (i2c->dev.of_node)
84  pdata = max77686_i2c_parse_dt_pdata(&i2c->dev);
85 
86  if (!pdata) {
87  ret = -EIO;
88  dev_err(&i2c->dev, "No platform data found.\n");
89  goto err;
90  }
91 
92  max77686 = kzalloc(sizeof(struct max77686_dev), GFP_KERNEL);
93  if (max77686 == NULL)
94  return -ENOMEM;
95 
96  max77686->regmap = regmap_init_i2c(i2c, &max77686_regmap_config);
97  if (IS_ERR(max77686->regmap)) {
98  ret = PTR_ERR(max77686->regmap);
99  dev_err(max77686->dev, "Failed to allocate register map: %d\n",
100  ret);
101  kfree(max77686);
102  return ret;
103  }
104 
105  i2c_set_clientdata(i2c, max77686);
106  max77686->dev = &i2c->dev;
107  max77686->i2c = i2c;
108  max77686->type = id->driver_data;
109 
110  max77686->wakeup = pdata->wakeup;
111  max77686->irq_gpio = pdata->irq_gpio;
112  max77686->irq = i2c->irq;
113 
114  if (regmap_read(max77686->regmap,
115  MAX77686_REG_DEVICE_ID, &data) < 0) {
116  dev_err(max77686->dev,
117  "device not found on this channel (this is not an error)\n");
118  ret = -ENODEV;
119  goto err;
120  } else
121  dev_info(max77686->dev, "device found\n");
122 
123  max77686->rtc = i2c_new_dummy(i2c->adapter, I2C_ADDR_RTC);
124  i2c_set_clientdata(max77686->rtc, max77686);
125 
126  max77686_irq_init(max77686);
127 
128  ret = mfd_add_devices(max77686->dev, -1, max77686_devs,
129  ARRAY_SIZE(max77686_devs), NULL, 0, NULL);
130 
131  if (ret < 0)
132  goto err_mfd;
133 
134  return ret;
135 
136 err_mfd:
137  mfd_remove_devices(max77686->dev);
138  i2c_unregister_device(max77686->rtc);
139 err:
140  kfree(max77686);
141  return ret;
142 }
143 
144 static int max77686_i2c_remove(struct i2c_client *i2c)
145 {
146  struct max77686_dev *max77686 = i2c_get_clientdata(i2c);
147 
148  mfd_remove_devices(max77686->dev);
149  i2c_unregister_device(max77686->rtc);
150  kfree(max77686);
151 
152  return 0;
153 }
154 
155 static const struct i2c_device_id max77686_i2c_id[] = {
156  { "max77686", TYPE_MAX77686 },
157  { }
158 };
159 MODULE_DEVICE_TABLE(i2c, max77686_i2c_id);
160 
161 static struct i2c_driver max77686_i2c_driver = {
162  .driver = {
163  .name = "max77686",
164  .owner = THIS_MODULE,
165  .of_match_table = of_match_ptr(max77686_pmic_dt_match),
166  },
167  .probe = max77686_i2c_probe,
168  .remove = max77686_i2c_remove,
169  .id_table = max77686_i2c_id,
170 };
171 
172 static int __init max77686_i2c_init(void)
173 {
174  return i2c_add_driver(&max77686_i2c_driver);
175 }
176 /* init early so consumer devices can complete system boot */
177 subsys_initcall(max77686_i2c_init);
178 
179 static void __exit max77686_i2c_exit(void)
180 {
181  i2c_del_driver(&max77686_i2c_driver);
182 }
183 module_exit(max77686_i2c_exit);
184 
185 MODULE_DESCRIPTION("MAXIM 77686 multi-function core driver");
186 MODULE_AUTHOR("Chiwoong Byun <[email protected]>");
187 MODULE_LICENSE("GPL");