1 /*
2 * HID over I2C Open Firmware Subclass
3 *
4 * Copyright (c) 2012 Benjamin Tissoires <benjamin.tissoires@gmail.com>
5 * Copyright (c) 2012 Ecole Nationale de l'Aviation Civile, France
6 * Copyright (c) 2012 Red Hat, Inc
7 *
8 * This code was forked out of the core code, which was partly based on
9 * "USB HID support for Linux":
10 *
11 * Copyright (c) 1999 Andreas Gal
12 * Copyright (c) 2000-2005 Vojtech Pavlik <vojtech@suse.cz>
13 * Copyright (c) 2005 Michael Haboustak <mike-@cinci.rr.com> for Concept2, Inc
14 * Copyright (c) 2007-2008 Oliver Neukum
15 * Copyright (c) 2006-2010 Jiri Kosina
16 *
17 * This file is subject to the terms and conditions of the GNU General Public
18 * License. See the file COPYING in the main directory of this archive for
19 * more details.
20 */
21
22 #include <linux/delay.h>
23 #include <linux/device.h>
24 #include <linux/i2c.h>
25 #include <linux/kernel.h>
26 #include <linux/module.h>
27 #include <linux/of.h>
28 #include <linux/pm.h>
29 #include <linux/regulator/consumer.h>
30
31 #include "i2c-hid.h"
32
33 struct i2c_hid_of {
34 struct i2chid_ops ops;
35
36 struct i2c_client *client;
37 struct regulator_bulk_data supplies[2];
38 int post_power_delay_ms;
39 };
40
i2c_hid_of_power_up(struct i2chid_ops * ops)41 static int i2c_hid_of_power_up(struct i2chid_ops *ops)
42 {
43 struct i2c_hid_of *ihid_of = container_of(ops, struct i2c_hid_of, ops);
44 struct device *dev = &ihid_of->client->dev;
45 int ret;
46
47 ret = regulator_bulk_enable(ARRAY_SIZE(ihid_of->supplies),
48 ihid_of->supplies);
49 if (ret) {
50 dev_warn(dev, "Failed to enable supplies: %d\n", ret);
51 return ret;
52 }
53
54 if (ihid_of->post_power_delay_ms)
55 msleep(ihid_of->post_power_delay_ms);
56
57 return 0;
58 }
59
i2c_hid_of_power_down(struct i2chid_ops * ops)60 static void i2c_hid_of_power_down(struct i2chid_ops *ops)
61 {
62 struct i2c_hid_of *ihid_of = container_of(ops, struct i2c_hid_of, ops);
63
64 regulator_bulk_disable(ARRAY_SIZE(ihid_of->supplies),
65 ihid_of->supplies);
66 }
67
i2c_hid_of_probe(struct i2c_client * client,const struct i2c_device_id * dev_id)68 static int i2c_hid_of_probe(struct i2c_client *client,
69 const struct i2c_device_id *dev_id)
70 {
71 struct device *dev = &client->dev;
72 struct i2c_hid_of *ihid_of;
73 u16 hid_descriptor_address;
74 int ret;
75 u32 val;
76
77 ihid_of = devm_kzalloc(&client->dev, sizeof(*ihid_of), GFP_KERNEL);
78 if (!ihid_of)
79 return -ENOMEM;
80
81 ihid_of->ops.power_up = i2c_hid_of_power_up;
82 ihid_of->ops.power_down = i2c_hid_of_power_down;
83
84 ret = of_property_read_u32(dev->of_node, "hid-descr-addr", &val);
85 if (ret) {
86 dev_err(&client->dev, "HID register address not provided\n");
87 return -ENODEV;
88 }
89 if (val >> 16) {
90 dev_err(&client->dev, "Bad HID register address: 0x%08x\n",
91 val);
92 return -EINVAL;
93 }
94 hid_descriptor_address = val;
95
96 if (!device_property_read_u32(&client->dev, "post-power-on-delay-ms",
97 &val))
98 ihid_of->post_power_delay_ms = val;
99
100 ihid_of->supplies[0].supply = "vdd";
101 ihid_of->supplies[1].supply = "vddl";
102 ret = devm_regulator_bulk_get(&client->dev,
103 ARRAY_SIZE(ihid_of->supplies),
104 ihid_of->supplies);
105 if (ret)
106 return ret;
107
108 return i2c_hid_core_probe(client, &ihid_of->ops,
109 hid_descriptor_address);
110 }
111
112 static const struct of_device_id i2c_hid_of_match[] = {
113 { .compatible = "hid-over-i2c" },
114 {},
115 };
116 MODULE_DEVICE_TABLE(of, i2c_hid_of_match);
117
118 static const struct i2c_device_id i2c_hid_of_id_table[] = {
119 { "hid", 0 },
120 { "hid-over-i2c", 0 },
121 { },
122 };
123 MODULE_DEVICE_TABLE(i2c, i2c_hid_of_id_table);
124
125 static struct i2c_driver i2c_hid_of_driver = {
126 .driver = {
127 .name = "i2c_hid_of",
128 .pm = &i2c_hid_core_pm,
129 .probe_type = PROBE_PREFER_ASYNCHRONOUS,
130 .of_match_table = of_match_ptr(i2c_hid_of_match),
131 },
132
133 .probe = i2c_hid_of_probe,
134 .remove = i2c_hid_core_remove,
135 .shutdown = i2c_hid_core_shutdown,
136 .id_table = i2c_hid_of_id_table,
137 };
138
139 module_i2c_driver(i2c_hid_of_driver);
140
141 MODULE_DESCRIPTION("HID over I2C OF driver");
142 MODULE_AUTHOR("Benjamin Tissoires <benjamin.tissoires@gmail.com>");
143 MODULE_LICENSE("GPL");
144