diff options
Diffstat (limited to 'drivers/mfd/max8925-i2c.c')
-rw-r--r-- | drivers/mfd/max8925-i2c.c | 210 |
1 files changed, 210 insertions, 0 deletions
diff --git a/drivers/mfd/max8925-i2c.c b/drivers/mfd/max8925-i2c.c new file mode 100644 index 000000000000..942068e730f9 --- /dev/null +++ b/drivers/mfd/max8925-i2c.c | |||
@@ -0,0 +1,210 @@ | |||
1 | /* | ||
2 | * I2C driver for Maxim MAX8925 | ||
3 | * | ||
4 | * Copyright (C) 2009 Marvell International Ltd. | ||
5 | * Haojian Zhuang <haojian.zhuang@marvell.com> | ||
6 | * | ||
7 | * This program is free software; you can redistribute it and/or modify | ||
8 | * it under the terms of the GNU General Public License version 2 as | ||
9 | * published by the Free Software Foundation. | ||
10 | */ | ||
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 | |||
17 | static inline int max8925_read_device(struct i2c_client *i2c, | ||
18 | int reg, int bytes, void *dest) | ||
19 | { | ||
20 | unsigned char data; | ||
21 | unsigned char *buf; | ||
22 | int ret; | ||
23 | |||
24 | buf = kzalloc(bytes + 1, GFP_KERNEL); | ||
25 | if (!buf) | ||
26 | return -ENOMEM; | ||
27 | |||
28 | data = (unsigned char)reg; | ||
29 | ret = i2c_master_send(i2c, &data, 1); | ||
30 | if (ret < 0) | ||
31 | return ret; | ||
32 | |||
33 | ret = i2c_master_recv(i2c, buf, bytes + 1); | ||
34 | if (ret < 0) | ||
35 | return ret; | ||
36 | memcpy(dest, buf, bytes); | ||
37 | return 0; | ||
38 | } | ||
39 | |||
40 | static inline int max8925_write_device(struct i2c_client *i2c, | ||
41 | int reg, int bytes, void *src) | ||
42 | { | ||
43 | unsigned char buf[bytes + 1]; | ||
44 | int ret; | ||
45 | |||
46 | buf[0] = (unsigned char)reg; | ||
47 | memcpy(&buf[1], src, bytes); | ||
48 | |||
49 | ret = i2c_master_send(i2c, buf, bytes + 1); | ||
50 | if (ret < 0) | ||
51 | return ret; | ||
52 | return 0; | ||
53 | } | ||
54 | |||
55 | int max8925_reg_read(struct i2c_client *i2c, int reg) | ||
56 | { | ||
57 | struct max8925_chip *chip = i2c_get_clientdata(i2c); | ||
58 | unsigned char data; | ||
59 | int ret; | ||
60 | |||
61 | mutex_lock(&chip->io_lock); | ||
62 | ret = max8925_read_device(i2c, reg, 1, &data); | ||
63 | mutex_unlock(&chip->io_lock); | ||
64 | |||
65 | if (ret < 0) | ||
66 | return ret; | ||
67 | else | ||
68 | return (int)data; | ||
69 | } | ||
70 | EXPORT_SYMBOL(max8925_reg_read); | ||
71 | |||
72 | int max8925_reg_write(struct i2c_client *i2c, int reg, | ||
73 | unsigned char data) | ||
74 | { | ||
75 | struct max8925_chip *chip = i2c_get_clientdata(i2c); | ||
76 | int ret; | ||
77 | |||
78 | mutex_lock(&chip->io_lock); | ||
79 | ret = max8925_write_device(i2c, reg, 1, &data); | ||
80 | mutex_unlock(&chip->io_lock); | ||
81 | |||
82 | return ret; | ||
83 | } | ||
84 | EXPORT_SYMBOL(max8925_reg_write); | ||
85 | |||
86 | int max8925_bulk_read(struct i2c_client *i2c, int reg, | ||
87 | int count, unsigned char *buf) | ||
88 | { | ||
89 | struct max8925_chip *chip = i2c_get_clientdata(i2c); | ||
90 | int ret; | ||
91 | |||
92 | mutex_lock(&chip->io_lock); | ||
93 | ret = max8925_read_device(i2c, reg, count, buf); | ||
94 | mutex_unlock(&chip->io_lock); | ||
95 | |||
96 | return ret; | ||
97 | } | ||
98 | EXPORT_SYMBOL(max8925_bulk_read); | ||
99 | |||
100 | int max8925_bulk_write(struct i2c_client *i2c, int reg, | ||
101 | int count, unsigned char *buf) | ||
102 | { | ||
103 | struct max8925_chip *chip = i2c_get_clientdata(i2c); | ||
104 | int ret; | ||
105 | |||
106 | mutex_lock(&chip->io_lock); | ||
107 | ret = max8925_write_device(i2c, reg, count, buf); | ||
108 | mutex_unlock(&chip->io_lock); | ||
109 | |||
110 | return ret; | ||
111 | } | ||
112 | EXPORT_SYMBOL(max8925_bulk_write); | ||
113 | |||
114 | int max8925_set_bits(struct i2c_client *i2c, int reg, | ||
115 | unsigned char mask, unsigned char data) | ||
116 | { | ||
117 | struct max8925_chip *chip = i2c_get_clientdata(i2c); | ||
118 | unsigned char value; | ||
119 | int ret; | ||
120 | |||
121 | mutex_lock(&chip->io_lock); | ||
122 | ret = max8925_read_device(i2c, reg, 1, &value); | ||
123 | if (ret < 0) | ||
124 | goto out; | ||
125 | value &= ~mask; | ||
126 | value |= data; | ||
127 | ret = max8925_write_device(i2c, reg, 1, &value); | ||
128 | out: | ||
129 | mutex_unlock(&chip->io_lock); | ||
130 | return ret; | ||
131 | } | ||
132 | EXPORT_SYMBOL(max8925_set_bits); | ||
133 | |||
134 | |||
135 | static const struct i2c_device_id max8925_id_table[] = { | ||
136 | { "max8925", 0 }, | ||
137 | {} | ||
138 | }; | ||
139 | MODULE_DEVICE_TABLE(i2c, max8925_id_table); | ||
140 | |||
141 | static int __devinit max8925_probe(struct i2c_client *client, | ||
142 | const struct i2c_device_id *id) | ||
143 | { | ||
144 | struct max8925_platform_data *pdata = client->dev.platform_data; | ||
145 | struct max8925_chip *chip; | ||
146 | |||
147 | if (!pdata) { | ||
148 | pr_info("%s: platform data is missing\n", __func__); | ||
149 | return -EINVAL; | ||
150 | } | ||
151 | if ((pdata->chip_id <= MAX8925_INVALID) | ||
152 | || (pdata->chip_id >= MAX8925_MAX)) { | ||
153 | pr_info("#%s: wrong chip identification\n", __func__); | ||
154 | return -EINVAL; | ||
155 | } | ||
156 | |||
157 | chip = kzalloc(sizeof(struct max8925_chip), GFP_KERNEL); | ||
158 | if (chip == NULL) | ||
159 | return -ENOMEM; | ||
160 | chip->i2c = client; | ||
161 | chip->chip_id = pdata->chip_id; | ||
162 | i2c_set_clientdata(client, chip); | ||
163 | chip->dev = &client->dev; | ||
164 | mutex_init(&chip->io_lock); | ||
165 | dev_set_drvdata(chip->dev, chip); | ||
166 | max8925_device_init(chip, pdata); | ||
167 | |||
168 | return 0; | ||
169 | } | ||
170 | |||
171 | static 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_set_clientdata(client, NULL); | ||
177 | kfree(chip); | ||
178 | return 0; | ||
179 | } | ||
180 | |||
181 | static struct i2c_driver max8925_driver = { | ||
182 | .driver = { | ||
183 | .name = "max8925", | ||
184 | .owner = THIS_MODULE, | ||
185 | }, | ||
186 | .probe = max8925_probe, | ||
187 | .remove = __devexit_p(max8925_remove), | ||
188 | .id_table = max8925_id_table, | ||
189 | }; | ||
190 | |||
191 | static int __init max8925_i2c_init(void) | ||
192 | { | ||
193 | int ret; | ||
194 | |||
195 | ret = i2c_add_driver(&max8925_driver); | ||
196 | if (ret != 0) | ||
197 | pr_err("Failed to register MAX8925 I2C driver: %d\n", ret); | ||
198 | return ret; | ||
199 | } | ||
200 | subsys_initcall(max8925_i2c_init); | ||
201 | |||
202 | static void __exit max8925_i2c_exit(void) | ||
203 | { | ||
204 | i2c_del_driver(&max8925_driver); | ||
205 | } | ||
206 | module_exit(max8925_i2c_exit); | ||
207 | |||
208 | MODULE_DESCRIPTION("I2C Driver for Maxim 8925"); | ||
209 | MODULE_AUTHOR("Haojian Zhuang <haojian.zhuang@marvell.com>"); | ||
210 | MODULE_LICENSE("GPL"); | ||