xref: /openbmc/linux/drivers/mfd/tps6507x.c (revision e23feb16)
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_device.h>
23 #include <linux/mfd/core.h>
24 #include <linux/mfd/tps6507x.h>
25 
26 static struct mfd_cell tps6507x_devs[] = {
27 	{
28 		.name = "tps6507x-pmic",
29 	},
30 	{
31 		.name = "tps6507x-ts",
32 	},
33 };
34 
35 
36 static int tps6507x_i2c_read_device(struct tps6507x_dev *tps6507x, char reg,
37 				  int bytes, void *dest)
38 {
39 	struct i2c_client *i2c = tps6507x->i2c_client;
40 	struct i2c_msg xfer[2];
41 	int ret;
42 
43 	/* Write register */
44 	xfer[0].addr = i2c->addr;
45 	xfer[0].flags = 0;
46 	xfer[0].len = 1;
47 	xfer[0].buf = &reg;
48 
49 	/* Read data */
50 	xfer[1].addr = i2c->addr;
51 	xfer[1].flags = I2C_M_RD;
52 	xfer[1].len = bytes;
53 	xfer[1].buf = dest;
54 
55 	ret = i2c_transfer(i2c->adapter, xfer, 2);
56 	if (ret == 2)
57 		ret = 0;
58 	else if (ret >= 0)
59 		ret = -EIO;
60 
61 	return ret;
62 }
63 
64 static int tps6507x_i2c_write_device(struct tps6507x_dev *tps6507x, char reg,
65 				   int bytes, void *src)
66 {
67 	struct i2c_client *i2c = tps6507x->i2c_client;
68 	/* we add 1 byte for device register */
69 	u8 msg[TPS6507X_MAX_REGISTER + 1];
70 	int ret;
71 
72 	if (bytes > TPS6507X_MAX_REGISTER)
73 		return -EINVAL;
74 
75 	msg[0] = reg;
76 	memcpy(&msg[1], src, bytes);
77 
78 	ret = i2c_master_send(i2c, msg, bytes + 1);
79 	if (ret < 0)
80 		return ret;
81 	if (ret != bytes + 1)
82 		return -EIO;
83 	return 0;
84 }
85 
86 static int tps6507x_i2c_probe(struct i2c_client *i2c,
87 			    const struct i2c_device_id *id)
88 {
89 	struct tps6507x_dev *tps6507x;
90 
91 	tps6507x = devm_kzalloc(&i2c->dev, sizeof(struct tps6507x_dev),
92 				GFP_KERNEL);
93 	if (tps6507x == NULL)
94 		return -ENOMEM;
95 
96 	i2c_set_clientdata(i2c, tps6507x);
97 	tps6507x->dev = &i2c->dev;
98 	tps6507x->i2c_client = i2c;
99 	tps6507x->read_dev = tps6507x_i2c_read_device;
100 	tps6507x->write_dev = tps6507x_i2c_write_device;
101 
102 	return mfd_add_devices(tps6507x->dev, -1, tps6507x_devs,
103 			       ARRAY_SIZE(tps6507x_devs), NULL, 0, NULL);
104 }
105 
106 static int tps6507x_i2c_remove(struct i2c_client *i2c)
107 {
108 	struct tps6507x_dev *tps6507x = i2c_get_clientdata(i2c);
109 
110 	mfd_remove_devices(tps6507x->dev);
111 	return 0;
112 }
113 
114 static const struct i2c_device_id tps6507x_i2c_id[] = {
115        { "tps6507x", 0 },
116        { }
117 };
118 MODULE_DEVICE_TABLE(i2c, tps6507x_i2c_id);
119 
120 #ifdef CONFIG_OF
121 static struct of_device_id tps6507x_of_match[] = {
122 	{.compatible = "ti,tps6507x", },
123 	{},
124 };
125 MODULE_DEVICE_TABLE(of, tps6507x_of_match);
126 #endif
127 
128 static struct i2c_driver tps6507x_i2c_driver = {
129 	.driver = {
130 		   .name = "tps6507x",
131 		   .owner = THIS_MODULE,
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");
154