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11#include <linux/kernel.h>
12#include <linux/module.h>
13#include <linux/platform_device.h>
14#include <linux/i2c.h>
15#include <linux/mfd/max8925.h>
16#include <linux/slab.h>
17
18#define RTC_I2C_ADDR 0x68
19#define ADC_I2C_ADDR 0x47
20
21static inline int max8925_read_device(struct i2c_client *i2c,
22 int reg, int bytes, void *dest)
23{
24 int ret;
25
26 if (bytes > 1)
27 ret = i2c_smbus_read_i2c_block_data(i2c, reg, bytes, dest);
28 else {
29 ret = i2c_smbus_read_byte_data(i2c, reg);
30 if (ret < 0)
31 return ret;
32 *(unsigned char *)dest = (unsigned char)ret;
33 }
34 return ret;
35}
36
37static inline int max8925_write_device(struct i2c_client *i2c,
38 int reg, int bytes, void *src)
39{
40 unsigned char buf[bytes + 1];
41 int ret;
42
43 buf[0] = (unsigned char)reg;
44 memcpy(&buf[1], src, bytes);
45
46 ret = i2c_master_send(i2c, buf, bytes + 1);
47 if (ret < 0)
48 return ret;
49 return 0;
50}
51
52int max8925_reg_read(struct i2c_client *i2c, int reg)
53{
54 struct max8925_chip *chip = i2c_get_clientdata(i2c);
55 unsigned char data = 0;
56 int ret;
57
58 mutex_lock(&chip->io_lock);
59 ret = max8925_read_device(i2c, reg, 1, &data);
60 mutex_unlock(&chip->io_lock);
61
62 if (ret < 0)
63 return ret;
64 else
65 return (int)data;
66}
67EXPORT_SYMBOL(max8925_reg_read);
68
69int max8925_reg_write(struct i2c_client *i2c, int reg,
70 unsigned char data)
71{
72 struct max8925_chip *chip = i2c_get_clientdata(i2c);
73 int ret;
74
75 mutex_lock(&chip->io_lock);
76 ret = max8925_write_device(i2c, reg, 1, &data);
77 mutex_unlock(&chip->io_lock);
78
79 return ret;
80}
81EXPORT_SYMBOL(max8925_reg_write);
82
83int max8925_bulk_read(struct i2c_client *i2c, int reg,
84 int count, unsigned char *buf)
85{
86 struct max8925_chip *chip = i2c_get_clientdata(i2c);
87 int ret;
88
89 mutex_lock(&chip->io_lock);
90 ret = max8925_read_device(i2c, reg, count, buf);
91 mutex_unlock(&chip->io_lock);
92
93 return ret;
94}
95EXPORT_SYMBOL(max8925_bulk_read);
96
97int max8925_bulk_write(struct i2c_client *i2c, int reg,
98 int count, unsigned char *buf)
99{
100 struct max8925_chip *chip = i2c_get_clientdata(i2c);
101 int ret;
102
103 mutex_lock(&chip->io_lock);
104 ret = max8925_write_device(i2c, reg, count, buf);
105 mutex_unlock(&chip->io_lock);
106
107 return ret;
108}
109EXPORT_SYMBOL(max8925_bulk_write);
110
111int max8925_set_bits(struct i2c_client *i2c, int reg,
112 unsigned char mask, unsigned char data)
113{
114 struct max8925_chip *chip = i2c_get_clientdata(i2c);
115 unsigned char value;
116 int ret;
117
118 mutex_lock(&chip->io_lock);
119 ret = max8925_read_device(i2c, reg, 1, &value);
120 if (ret < 0)
121 goto out;
122 value &= ~mask;
123 value |= data;
124 ret = max8925_write_device(i2c, reg, 1, &value);
125out:
126 mutex_unlock(&chip->io_lock);
127 return ret;
128}
129EXPORT_SYMBOL(max8925_set_bits);
130
131
132static const struct i2c_device_id max8925_id_table[] = {
133 { "max8925", 0 },
134 { },
135};
136MODULE_DEVICE_TABLE(i2c, max8925_id_table);
137
138static int __devinit max8925_probe(struct i2c_client *client,
139 const struct i2c_device_id *id)
140{
141 struct max8925_platform_data *pdata = client->dev.platform_data;
142 static struct max8925_chip *chip;
143
144 if (!pdata) {
145 pr_info("%s: platform data is missing\n", __func__);
146 return -EINVAL;
147 }
148
149 chip = kzalloc(sizeof(struct max8925_chip), GFP_KERNEL);
150 if (chip == NULL)
151 return -ENOMEM;
152 chip->i2c = client;
153 chip->dev = &client->dev;
154 i2c_set_clientdata(client, chip);
155 dev_set_drvdata(chip->dev, chip);
156 mutex_init(&chip->io_lock);
157
158 chip->rtc = i2c_new_dummy(chip->i2c->adapter, RTC_I2C_ADDR);
159 i2c_set_clientdata(chip->rtc, chip);
160
161 chip->adc = i2c_new_dummy(chip->i2c->adapter, ADC_I2C_ADDR);
162 i2c_set_clientdata(chip->adc, chip);
163
164 device_init_wakeup(&client->dev, 1);
165
166 max8925_device_init(chip, pdata);
167
168 return 0;
169}
170
171static int __devexit max8925_remove(struct i2c_client *client)
172{
173 struct max8925_chip *chip = i2c_get_clientdata(client);
174
175 max8925_device_exit(chip);
176 i2c_unregister_device(chip->adc);
177 i2c_unregister_device(chip->rtc);
178 kfree(chip);
179 return 0;
180}
181
182#ifdef CONFIG_PM_SLEEP
183static int max8925_suspend(struct device *dev)
184{
185 struct i2c_client *client = container_of(dev, struct i2c_client, dev);
186 struct max8925_chip *chip = i2c_get_clientdata(client);
187
188 if (device_may_wakeup(dev) && chip->wakeup_flag)
189 enable_irq_wake(chip->core_irq);
190 return 0;
191}
192
193static int max8925_resume(struct device *dev)
194{
195 struct i2c_client *client = container_of(dev, struct i2c_client, dev);
196 struct max8925_chip *chip = i2c_get_clientdata(client);
197
198 if (device_may_wakeup(dev) && chip->wakeup_flag)
199 disable_irq_wake(chip->core_irq);
200 return 0;
201}
202#endif
203
204static SIMPLE_DEV_PM_OPS(max8925_pm_ops, max8925_suspend, max8925_resume);
205
206static struct i2c_driver max8925_driver = {
207 .driver = {
208 .name = "max8925",
209 .owner = THIS_MODULE,
210 .pm = &max8925_pm_ops,
211 },
212 .probe = max8925_probe,
213 .remove = __devexit_p(max8925_remove),
214 .id_table = max8925_id_table,
215};
216
217static int __init max8925_i2c_init(void)
218{
219 int ret;
220
221 ret = i2c_add_driver(&max8925_driver);
222 if (ret != 0)
223 pr_err("Failed to register MAX8925 I2C driver: %d\n", ret);
224 return ret;
225}
226subsys_initcall(max8925_i2c_init);
227
228static void __exit max8925_i2c_exit(void)
229{
230 i2c_del_driver(&max8925_driver);
231}
232module_exit(max8925_i2c_exit);
233
234MODULE_DESCRIPTION("I2C Driver for Maxim 8925");
235MODULE_AUTHOR("Haojian Zhuang <haojian.zhuang@marvell.com>");
236MODULE_LICENSE("GPL");
237
