xref: /openbmc/linux/drivers/mfd/tps6507x.c (revision 6c33a6f4)
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 devm_mfd_add_devices(tps6507x->dev, -1, tps6507x_devs,
104 				    ARRAY_SIZE(tps6507x_devs), NULL, 0, NULL);
105 }
106 
107 static const struct i2c_device_id tps6507x_i2c_id[] = {
108 	{ "tps6507x", 0 },
109 	{ }
110 };
111 MODULE_DEVICE_TABLE(i2c, tps6507x_i2c_id);
112 
113 #ifdef CONFIG_OF
114 static const struct of_device_id tps6507x_of_match[] = {
115 	{.compatible = "ti,tps6507x", },
116 	{},
117 };
118 MODULE_DEVICE_TABLE(of, tps6507x_of_match);
119 #endif
120 
121 static struct i2c_driver tps6507x_i2c_driver = {
122 	.driver = {
123 		   .name = "tps6507x",
124 		   .of_match_table = of_match_ptr(tps6507x_of_match),
125 	},
126 	.probe = tps6507x_i2c_probe,
127 	.id_table = tps6507x_i2c_id,
128 };
129 
130 static int __init tps6507x_i2c_init(void)
131 {
132 	return i2c_add_driver(&tps6507x_i2c_driver);
133 }
134 /* init early so consumer devices can complete system boot */
135 subsys_initcall(tps6507x_i2c_init);
136 
137 static void __exit tps6507x_i2c_exit(void)
138 {
139 	i2c_del_driver(&tps6507x_i2c_driver);
140 }
141 module_exit(tps6507x_i2c_exit);
142 
143 MODULE_DESCRIPTION("TPS6507x chip family multi-function driver");
144 MODULE_LICENSE("GPL");
145