diff options
Diffstat (limited to 'drivers/mfd/wm831x-i2c.c')
-rw-r--r-- | drivers/mfd/wm831x-i2c.c | 155 |
1 files changed, 155 insertions, 0 deletions
diff --git a/drivers/mfd/wm831x-i2c.c b/drivers/mfd/wm831x-i2c.c new file mode 100644 index 000000000000..a06cbc739716 --- /dev/null +++ b/drivers/mfd/wm831x-i2c.c | |||
@@ -0,0 +1,155 @@ | |||
1 | /* | ||
2 | * wm831x-i2c.c -- I2C access for Wolfson WM831x PMICs | ||
3 | * | ||
4 | * Copyright 2009,2010 Wolfson Microelectronics PLC. | ||
5 | * | ||
6 | * Author: Mark Brown <broonie@opensource.wolfsonmicro.com> | ||
7 | * | ||
8 | * This program is free software; you can redistribute it and/or modify it | ||
9 | * under the terms of the GNU General Public License as published by the | ||
10 | * Free Software Foundation; either version 2 of the License, or (at your | ||
11 | * option) any later version. | ||
12 | * | ||
13 | */ | ||
14 | |||
15 | #include <linux/kernel.h> | ||
16 | #include <linux/module.h> | ||
17 | #include <linux/i2c.h> | ||
18 | #include <linux/delay.h> | ||
19 | #include <linux/mfd/core.h> | ||
20 | #include <linux/slab.h> | ||
21 | |||
22 | #include <linux/mfd/wm831x/core.h> | ||
23 | #include <linux/mfd/wm831x/pdata.h> | ||
24 | |||
25 | static int wm831x_i2c_read_device(struct wm831x *wm831x, unsigned short reg, | ||
26 | int bytes, void *dest) | ||
27 | { | ||
28 | struct i2c_client *i2c = wm831x->control_data; | ||
29 | int ret; | ||
30 | u16 r = cpu_to_be16(reg); | ||
31 | |||
32 | ret = i2c_master_send(i2c, (unsigned char *)&r, 2); | ||
33 | if (ret < 0) | ||
34 | return ret; | ||
35 | if (ret != 2) | ||
36 | return -EIO; | ||
37 | |||
38 | ret = i2c_master_recv(i2c, dest, bytes); | ||
39 | if (ret < 0) | ||
40 | return ret; | ||
41 | if (ret != bytes) | ||
42 | return -EIO; | ||
43 | return 0; | ||
44 | } | ||
45 | |||
46 | /* Currently we allocate the write buffer on the stack; this is OK for | ||
47 | * small writes - if we need to do large writes this will need to be | ||
48 | * revised. | ||
49 | */ | ||
50 | static int wm831x_i2c_write_device(struct wm831x *wm831x, unsigned short reg, | ||
51 | int bytes, void *src) | ||
52 | { | ||
53 | struct i2c_client *i2c = wm831x->control_data; | ||
54 | struct i2c_msg xfer[2]; | ||
55 | int ret; | ||
56 | |||
57 | reg = cpu_to_be16(reg); | ||
58 | |||
59 | xfer[0].addr = i2c->addr; | ||
60 | xfer[0].flags = 0; | ||
61 | xfer[0].len = 2; | ||
62 | xfer[0].buf = (char *)® | ||
63 | |||
64 | xfer[1].addr = i2c->addr; | ||
65 | xfer[1].flags = I2C_M_NOSTART; | ||
66 | xfer[1].len = bytes; | ||
67 | xfer[1].buf = (char *)src; | ||
68 | |||
69 | ret = i2c_transfer(i2c->adapter, xfer, 2); | ||
70 | if (ret < 0) | ||
71 | return ret; | ||
72 | if (ret != 2) | ||
73 | return -EIO; | ||
74 | |||
75 | return 0; | ||
76 | } | ||
77 | |||
78 | static int wm831x_i2c_probe(struct i2c_client *i2c, | ||
79 | const struct i2c_device_id *id) | ||
80 | { | ||
81 | struct wm831x *wm831x; | ||
82 | |||
83 | wm831x = kzalloc(sizeof(struct wm831x), GFP_KERNEL); | ||
84 | if (wm831x == NULL) | ||
85 | return -ENOMEM; | ||
86 | |||
87 | i2c_set_clientdata(i2c, wm831x); | ||
88 | wm831x->dev = &i2c->dev; | ||
89 | wm831x->control_data = i2c; | ||
90 | wm831x->read_dev = wm831x_i2c_read_device; | ||
91 | wm831x->write_dev = wm831x_i2c_write_device; | ||
92 | |||
93 | return wm831x_device_init(wm831x, id->driver_data, i2c->irq); | ||
94 | } | ||
95 | |||
96 | static int wm831x_i2c_remove(struct i2c_client *i2c) | ||
97 | { | ||
98 | struct wm831x *wm831x = i2c_get_clientdata(i2c); | ||
99 | |||
100 | wm831x_device_exit(wm831x); | ||
101 | |||
102 | return 0; | ||
103 | } | ||
104 | |||
105 | static int wm831x_i2c_suspend(struct device *dev) | ||
106 | { | ||
107 | struct wm831x *wm831x = dev_get_drvdata(dev); | ||
108 | |||
109 | return wm831x_device_suspend(wm831x); | ||
110 | } | ||
111 | |||
112 | static const struct i2c_device_id wm831x_i2c_id[] = { | ||
113 | { "wm8310", WM8310 }, | ||
114 | { "wm8311", WM8311 }, | ||
115 | { "wm8312", WM8312 }, | ||
116 | { "wm8320", WM8320 }, | ||
117 | { "wm8321", WM8321 }, | ||
118 | { "wm8325", WM8325 }, | ||
119 | { "wm8326", WM8326 }, | ||
120 | { } | ||
121 | }; | ||
122 | MODULE_DEVICE_TABLE(i2c, wm831x_i2c_id); | ||
123 | |||
124 | static const struct dev_pm_ops wm831x_pm_ops = { | ||
125 | .suspend = wm831x_i2c_suspend, | ||
126 | }; | ||
127 | |||
128 | static struct i2c_driver wm831x_i2c_driver = { | ||
129 | .driver = { | ||
130 | .name = "wm831x", | ||
131 | .owner = THIS_MODULE, | ||
132 | .pm = &wm831x_pm_ops, | ||
133 | }, | ||
134 | .probe = wm831x_i2c_probe, | ||
135 | .remove = wm831x_i2c_remove, | ||
136 | .id_table = wm831x_i2c_id, | ||
137 | }; | ||
138 | |||
139 | static int __init wm831x_i2c_init(void) | ||
140 | { | ||
141 | int ret; | ||
142 | |||
143 | ret = i2c_add_driver(&wm831x_i2c_driver); | ||
144 | if (ret != 0) | ||
145 | pr_err("Failed to register wm831x I2C driver: %d\n", ret); | ||
146 | |||
147 | return ret; | ||
148 | } | ||
149 | subsys_initcall(wm831x_i2c_init); | ||
150 | |||
151 | static void __exit wm831x_i2c_exit(void) | ||
152 | { | ||
153 | i2c_del_driver(&wm831x_i2c_driver); | ||
154 | } | ||
155 | module_exit(wm831x_i2c_exit); | ||