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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 
i2c_hid_of_power_up(struct i2chid_ops * ops)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 
i2c_hid_of_power_down(struct i2chid_ops * ops)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 
i2c_hid_of_probe(struct i2c_client * client,const struct i2c_device_id * dev_id)69 static int i2c_hid_of_probe(struct i2c_client *client,
70 			    const struct i2c_device_id *dev_id)
71 {
72 	struct device *dev = &client->dev;
73 	struct i2c_hid_of *ihid_of;
74 	u16 hid_descriptor_address;
75 	u32 quirks = 0;
76 	int ret;
77 	u32 val;
78 
79 	ihid_of = devm_kzalloc(&client->dev, sizeof(*ihid_of), GFP_KERNEL);
80 	if (!ihid_of)
81 		return -ENOMEM;
82 
83 	ihid_of->client = client;
84 	ihid_of->ops.power_up = i2c_hid_of_power_up;
85 	ihid_of->ops.power_down = i2c_hid_of_power_down;
86 
87 	ret = of_property_read_u32(dev->of_node, "hid-descr-addr", &val);
88 	if (ret) {
89 		dev_err(&client->dev, "HID register address not provided\n");
90 		return -ENODEV;
91 	}
92 	if (val >> 16) {
93 		dev_err(&client->dev, "Bad HID register address: 0x%08x\n",
94 			val);
95 		return -EINVAL;
96 	}
97 	hid_descriptor_address = val;
98 
99 	if (!device_property_read_u32(&client->dev, "post-power-on-delay-ms",
100 				      &val))
101 		ihid_of->post_power_delay_ms = val;
102 
103 	ihid_of->supplies[0].supply = "vdd";
104 	ihid_of->supplies[1].supply = "vddl";
105 	ret = devm_regulator_bulk_get(&client->dev,
106 				      ARRAY_SIZE(ihid_of->supplies),
107 				      ihid_of->supplies);
108 	if (ret)
109 		return ret;
110 
111 	if (device_property_read_bool(dev, "touchscreen-inverted-x"))
112 		quirks |= HID_QUIRK_X_INVERT;
113 
114 	if (device_property_read_bool(dev, "touchscreen-inverted-y"))
115 		quirks |= HID_QUIRK_Y_INVERT;
116 
117 	return i2c_hid_core_probe(client, &ihid_of->ops,
118 				  hid_descriptor_address, quirks);
119 }
120 
121 static const struct of_device_id i2c_hid_of_match[] = {
122 	{ .compatible = "hid-over-i2c" },
123 	{},
124 };
125 MODULE_DEVICE_TABLE(of, i2c_hid_of_match);
126 
127 static const struct i2c_device_id i2c_hid_of_id_table[] = {
128 	{ "hid", 0 },
129 	{ "hid-over-i2c", 0 },
130 	{ },
131 };
132 MODULE_DEVICE_TABLE(i2c, i2c_hid_of_id_table);
133 
134 static struct i2c_driver i2c_hid_of_driver = {
135 	.driver = {
136 		.name	= "i2c_hid_of",
137 		.pm	= &i2c_hid_core_pm,
138 		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
139 		.of_match_table = of_match_ptr(i2c_hid_of_match),
140 	},
141 
142 	.probe		= i2c_hid_of_probe,
143 	.remove		= i2c_hid_core_remove,
144 	.shutdown	= i2c_hid_core_shutdown,
145 	.id_table	= i2c_hid_of_id_table,
146 };
147 
148 module_i2c_driver(i2c_hid_of_driver);
149 
150 MODULE_DESCRIPTION("HID over I2C OF driver");
151 MODULE_AUTHOR("Benjamin Tissoires <benjamin.tissoires@gmail.com>");
152 MODULE_LICENSE("GPL");
153