GNU Linux-libre 4.4.289-gnu1
[releases.git] / drivers / mfd / tps6507x.c
1 /*
2  * tps6507x.c  --  TPS6507x chip family multi-function driver
3  *
4  *  Copyright (c) 2010 RidgeRun (todd.fischer@ridgerun.com)
5  *
6  * Author: Todd Fischer
7  *         todd.fischer@ridgerun.com
8  *
9  * Credits:
10  *
11  *    Using code from wm831x-*.c, wm8400-core, Wolfson Microelectronics PLC.
12  *
13  * For licencing details see kernel-base/COPYING
14  *
15  */
16
17 #include <linux/module.h>
18 #include <linux/moduleparam.h>
19 #include <linux/init.h>
20 #include <linux/slab.h>
21 #include <linux/i2c.h>
22 #include <linux/of.h>
23 #include <linux/of_device.h>
24 #include <linux/mfd/core.h>
25 #include <linux/mfd/tps6507x.h>
26
27 static const struct mfd_cell tps6507x_devs[] = {
28         {
29                 .name = "tps6507x-pmic",
30         },
31         {
32                 .name = "tps6507x-ts",
33         },
34 };
35
36
37 static int tps6507x_i2c_read_device(struct tps6507x_dev *tps6507x, char reg,
38                                   int bytes, void *dest)
39 {
40         struct i2c_client *i2c = tps6507x->i2c_client;
41         struct i2c_msg xfer[2];
42         int ret;
43
44         /* Write register */
45         xfer[0].addr = i2c->addr;
46         xfer[0].flags = 0;
47         xfer[0].len = 1;
48         xfer[0].buf = &reg;
49
50         /* Read data */
51         xfer[1].addr = i2c->addr;
52         xfer[1].flags = I2C_M_RD;
53         xfer[1].len = bytes;
54         xfer[1].buf = dest;
55
56         ret = i2c_transfer(i2c->adapter, xfer, 2);
57         if (ret == 2)
58                 ret = 0;
59         else if (ret >= 0)
60                 ret = -EIO;
61
62         return ret;
63 }
64
65 static int tps6507x_i2c_write_device(struct tps6507x_dev *tps6507x, char reg,
66                                    int bytes, void *src)
67 {
68         struct i2c_client *i2c = tps6507x->i2c_client;
69         /* we add 1 byte for device register */
70         u8 msg[TPS6507X_MAX_REGISTER + 1];
71         int ret;
72
73         if (bytes > TPS6507X_MAX_REGISTER)
74                 return -EINVAL;
75
76         msg[0] = reg;
77         memcpy(&msg[1], src, bytes);
78
79         ret = i2c_master_send(i2c, msg, bytes + 1);
80         if (ret < 0)
81                 return ret;
82         if (ret != bytes + 1)
83                 return -EIO;
84         return 0;
85 }
86
87 static int tps6507x_i2c_probe(struct i2c_client *i2c,
88                             const struct i2c_device_id *id)
89 {
90         struct tps6507x_dev *tps6507x;
91
92         tps6507x = devm_kzalloc(&i2c->dev, sizeof(struct tps6507x_dev),
93                                 GFP_KERNEL);
94         if (tps6507x == NULL)
95                 return -ENOMEM;
96
97         i2c_set_clientdata(i2c, tps6507x);
98         tps6507x->dev = &i2c->dev;
99         tps6507x->i2c_client = i2c;
100         tps6507x->read_dev = tps6507x_i2c_read_device;
101         tps6507x->write_dev = tps6507x_i2c_write_device;
102
103         return mfd_add_devices(tps6507x->dev, -1, tps6507x_devs,
104                                ARRAY_SIZE(tps6507x_devs), NULL, 0, NULL);
105 }
106
107 static int tps6507x_i2c_remove(struct i2c_client *i2c)
108 {
109         struct tps6507x_dev *tps6507x = i2c_get_clientdata(i2c);
110
111         mfd_remove_devices(tps6507x->dev);
112         return 0;
113 }
114
115 static const struct i2c_device_id tps6507x_i2c_id[] = {
116        { "tps6507x", 0 },
117        { }
118 };
119 MODULE_DEVICE_TABLE(i2c, tps6507x_i2c_id);
120
121 #ifdef CONFIG_OF
122 static const struct of_device_id tps6507x_of_match[] = {
123         {.compatible = "ti,tps6507x", },
124         {},
125 };
126 MODULE_DEVICE_TABLE(of, tps6507x_of_match);
127 #endif
128
129 static struct i2c_driver tps6507x_i2c_driver = {
130         .driver = {
131                    .name = "tps6507x",
132                    .of_match_table = of_match_ptr(tps6507x_of_match),
133         },
134         .probe = tps6507x_i2c_probe,
135         .remove = tps6507x_i2c_remove,
136         .id_table = tps6507x_i2c_id,
137 };
138
139 static int __init tps6507x_i2c_init(void)
140 {
141         return i2c_add_driver(&tps6507x_i2c_driver);
142 }
143 /* init early so consumer devices can complete system boot */
144 subsys_initcall(tps6507x_i2c_init);
145
146 static void __exit tps6507x_i2c_exit(void)
147 {
148         i2c_del_driver(&tps6507x_i2c_driver);
149 }
150 module_exit(tps6507x_i2c_exit);
151
152 MODULE_DESCRIPTION("TPS6507x chip family multi-function driver");
153 MODULE_LICENSE("GPL");