xref: /openbmc/linux/drivers/hid/i2c-hid/i2c-hid-of.c (revision c699ce1a)
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/hid.h>
25 #include <linux/i2c.h>
26 #include <linux/kernel.h>
27 #include <linux/module.h>
28 #include <linux/of.h>
29 #include <linux/pm.h>
30 #include <linux/regulator/consumer.h>
31 
32 #include "i2c-hid.h"
33 
34 struct i2c_hid_of {
35 	struct i2chid_ops ops;
36 
37 	struct i2c_client *client;
38 	struct regulator_bulk_data supplies[2];
39 	int post_power_delay_ms;
40 };
41 
42 static int i2c_hid_of_power_up(struct i2chid_ops *ops)
43 {
44 	struct i2c_hid_of *ihid_of = container_of(ops, struct i2c_hid_of, ops);
45 	struct device *dev = &ihid_of->client->dev;
46 	int ret;
47 
48 	ret = regulator_bulk_enable(ARRAY_SIZE(ihid_of->supplies),
49 				    ihid_of->supplies);
50 	if (ret) {
51 		dev_warn(dev, "Failed to enable supplies: %d\n", ret);
52 		return ret;
53 	}
54 
55 	if (ihid_of->post_power_delay_ms)
56 		msleep(ihid_of->post_power_delay_ms);
57 
58 	return 0;
59 }
60 
61 static void i2c_hid_of_power_down(struct i2chid_ops *ops)
62 {
63 	struct i2c_hid_of *ihid_of = container_of(ops, struct i2c_hid_of, ops);
64 
65 	regulator_bulk_disable(ARRAY_SIZE(ihid_of->supplies),
66 			       ihid_of->supplies);
67 }
68 
69 static int i2c_hid_of_probe(struct i2c_client *client)
70 {
71 	struct device *dev = &client->dev;
72 	struct i2c_hid_of *ihid_of;
73 	u16 hid_descriptor_address;
74 	u32 quirks = 0;
75 	int ret;
76 	u32 val;
77 
78 	ihid_of = devm_kzalloc(&client->dev, sizeof(*ihid_of), GFP_KERNEL);
79 	if (!ihid_of)
80 		return -ENOMEM;
81 
82 	ihid_of->ops.power_up = i2c_hid_of_power_up;
83 	ihid_of->ops.power_down = i2c_hid_of_power_down;
84 
85 	ret = of_property_read_u32(dev->of_node, "hid-descr-addr", &val);
86 	if (ret) {
87 		dev_err(&client->dev, "HID register address not provided\n");
88 		return -ENODEV;
89 	}
90 	if (val >> 16) {
91 		dev_err(&client->dev, "Bad HID register address: 0x%08x\n",
92 			val);
93 		return -EINVAL;
94 	}
95 	hid_descriptor_address = val;
96 
97 	if (!device_property_read_u32(&client->dev, "post-power-on-delay-ms",
98 				      &val))
99 		ihid_of->post_power_delay_ms = val;
100 
101 	ihid_of->supplies[0].supply = "vdd";
102 	ihid_of->supplies[1].supply = "vddl";
103 	ret = devm_regulator_bulk_get(&client->dev,
104 				      ARRAY_SIZE(ihid_of->supplies),
105 				      ihid_of->supplies);
106 	if (ret)
107 		return ret;
108 
109 	if (device_property_read_bool(dev, "touchscreen-inverted-x"))
110 		quirks |= HID_QUIRK_X_INVERT;
111 
112 	if (device_property_read_bool(dev, "touchscreen-inverted-y"))
113 		quirks |= HID_QUIRK_Y_INVERT;
114 
115 	return i2c_hid_core_probe(client, &ihid_of->ops,
116 				  hid_descriptor_address, quirks);
117 }
118 
119 static const struct of_device_id i2c_hid_of_match[] = {
120 	{ .compatible = "hid-over-i2c" },
121 	{},
122 };
123 MODULE_DEVICE_TABLE(of, i2c_hid_of_match);
124 
125 static const struct i2c_device_id i2c_hid_of_id_table[] = {
126 	{ "hid", 0 },
127 	{ "hid-over-i2c", 0 },
128 	{ },
129 };
130 MODULE_DEVICE_TABLE(i2c, i2c_hid_of_id_table);
131 
132 static struct i2c_driver i2c_hid_of_driver = {
133 	.driver = {
134 		.name	= "i2c_hid_of",
135 		.pm	= &i2c_hid_core_pm,
136 		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
137 		.of_match_table = of_match_ptr(i2c_hid_of_match),
138 	},
139 
140 	.probe_new	= i2c_hid_of_probe,
141 	.remove		= i2c_hid_core_remove,
142 	.shutdown	= i2c_hid_core_shutdown,
143 	.id_table	= i2c_hid_of_id_table,
144 };
145 
146 module_i2c_driver(i2c_hid_of_driver);
147 
148 MODULE_DESCRIPTION("HID over I2C OF driver");
149 MODULE_AUTHOR("Benjamin Tissoires <benjamin.tissoires@gmail.com>");
150 MODULE_LICENSE("GPL");
151