xref: /linux/drivers/mfd/tps6507x.c (revision 60e13231561b3a4c5269bfa1ef6c0569ad6f28ec)
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/mfd/core.h>
23 #include <linux/mfd/tps6507x.h>
24 
25 static struct mfd_cell tps6507x_devs[] = {
26 	{
27 		.name = "tps6507x-pmic",
28 	},
29 	{
30 		.name = "tps6507x-ts",
31 	},
32 };
33 
34 
35 static int tps6507x_i2c_read_device(struct tps6507x_dev *tps6507x, char reg,
36 				  int bytes, void *dest)
37 {
38 	struct i2c_client *i2c = tps6507x->i2c_client;
39 	struct i2c_msg xfer[2];
40 	int ret;
41 
42 	/* Write register */
43 	xfer[0].addr = i2c->addr;
44 	xfer[0].flags = 0;
45 	xfer[0].len = 1;
46 	xfer[0].buf = &reg;
47 
48 	/* Read data */
49 	xfer[1].addr = i2c->addr;
50 	xfer[1].flags = I2C_M_RD;
51 	xfer[1].len = bytes;
52 	xfer[1].buf = dest;
53 
54 	ret = i2c_transfer(i2c->adapter, xfer, 2);
55 	if (ret == 2)
56 		ret = 0;
57 	else if (ret >= 0)
58 		ret = -EIO;
59 
60 	return ret;
61 }
62 
63 static int tps6507x_i2c_write_device(struct tps6507x_dev *tps6507x, char reg,
64 				   int bytes, void *src)
65 {
66 	struct i2c_client *i2c = tps6507x->i2c_client;
67 	/* we add 1 byte for device register */
68 	u8 msg[TPS6507X_MAX_REGISTER + 1];
69 	int ret;
70 
71 	if (bytes > TPS6507X_MAX_REGISTER)
72 		return -EINVAL;
73 
74 	msg[0] = reg;
75 	memcpy(&msg[1], src, bytes);
76 
77 	ret = i2c_master_send(i2c, msg, bytes + 1);
78 	if (ret < 0)
79 		return ret;
80 	if (ret != bytes + 1)
81 		return -EIO;
82 	return 0;
83 }
84 
85 static int tps6507x_i2c_probe(struct i2c_client *i2c,
86 			    const struct i2c_device_id *id)
87 {
88 	struct tps6507x_dev *tps6507x;
89 	int ret = 0;
90 
91 	tps6507x = kzalloc(sizeof(struct tps6507x_dev), GFP_KERNEL);
92 	if (tps6507x == NULL)
93 		return -ENOMEM;
94 
95 	i2c_set_clientdata(i2c, tps6507x);
96 	tps6507x->dev = &i2c->dev;
97 	tps6507x->i2c_client = i2c;
98 	tps6507x->read_dev = tps6507x_i2c_read_device;
99 	tps6507x->write_dev = tps6507x_i2c_write_device;
100 
101 	ret = mfd_add_devices(tps6507x->dev, -1,
102 			      tps6507x_devs, ARRAY_SIZE(tps6507x_devs),
103 			      NULL, 0);
104 
105 	if (ret < 0)
106 		goto err;
107 
108 	return ret;
109 
110 err:
111 	mfd_remove_devices(tps6507x->dev);
112 	kfree(tps6507x);
113 	return ret;
114 }
115 
116 static int tps6507x_i2c_remove(struct i2c_client *i2c)
117 {
118 	struct tps6507x_dev *tps6507x = i2c_get_clientdata(i2c);
119 
120 	mfd_remove_devices(tps6507x->dev);
121 	kfree(tps6507x);
122 
123 	return 0;
124 }
125 
126 static const struct i2c_device_id tps6507x_i2c_id[] = {
127        { "tps6507x", 0 },
128        { }
129 };
130 MODULE_DEVICE_TABLE(i2c, tps6507x_i2c_id);
131 
132 
133 static struct i2c_driver tps6507x_i2c_driver = {
134 	.driver = {
135 		   .name = "tps6507x",
136 		   .owner = THIS_MODULE,
137 	},
138 	.probe = tps6507x_i2c_probe,
139 	.remove = tps6507x_i2c_remove,
140 	.id_table = tps6507x_i2c_id,
141 };
142 
143 static int __init tps6507x_i2c_init(void)
144 {
145 	return i2c_add_driver(&tps6507x_i2c_driver);
146 }
147 /* init early so consumer devices can complete system boot */
148 subsys_initcall(tps6507x_i2c_init);
149 
150 static void __exit tps6507x_i2c_exit(void)
151 {
152 	i2c_del_driver(&tps6507x_i2c_driver);
153 }
154 module_exit(tps6507x_i2c_exit);
155 
156 MODULE_DESCRIPTION("TPS6507x chip family multi-function driver");
157 MODULE_LICENSE("GPL");
158