GNU Linux-libre 4.9.328-gnu1
[releases.git] / drivers / input / touchscreen / ar1021_i2c.c
1 /*
2  * Microchip AR1021 driver for I2C
3  *
4  * Author: Christian Gmeiner <christian.gmeiner@gmail.com>
5  *
6  * License: GPLv2 as published by the FSF.
7  */
8
9 #include <linux/module.h>
10 #include <linux/input.h>
11 #include <linux/of.h>
12 #include <linux/i2c.h>
13 #include <linux/irq.h>
14 #include <linux/interrupt.h>
15
16 #define AR1021_TOCUH_PKG_SIZE   5
17
18 #define AR1021_MAX_X    4095
19 #define AR1021_MAX_Y    4095
20
21 struct ar1021_i2c {
22         struct i2c_client *client;
23         struct input_dev *input;
24         u8 data[AR1021_TOCUH_PKG_SIZE];
25 };
26
27 static irqreturn_t ar1021_i2c_irq(int irq, void *dev_id)
28 {
29         struct ar1021_i2c *ar1021 = dev_id;
30         struct input_dev *input = ar1021->input;
31         u8 *data = ar1021->data;
32         unsigned int x, y, button;
33         int retval;
34
35         retval = i2c_master_recv(ar1021->client,
36                                 ar1021->data, sizeof(ar1021->data));
37         if (retval != sizeof(ar1021->data))
38                 goto out;
39
40         /* sync bit set ? */
41         if ((data[0] & 0x80) == 0)
42                 goto out;
43
44         button = data[0] & BIT(0);
45         x = ((data[2] & 0x1f) << 7) | (data[1] & 0x7f);
46         y = ((data[4] & 0x1f) << 7) | (data[3] & 0x7f);
47
48         input_report_abs(input, ABS_X, x);
49         input_report_abs(input, ABS_Y, y);
50         input_report_key(input, BTN_TOUCH, button);
51         input_sync(input);
52
53 out:
54         return IRQ_HANDLED;
55 }
56
57 static int ar1021_i2c_open(struct input_dev *dev)
58 {
59         struct ar1021_i2c *ar1021 = input_get_drvdata(dev);
60         struct i2c_client *client = ar1021->client;
61
62         enable_irq(client->irq);
63
64         return 0;
65 }
66
67 static void ar1021_i2c_close(struct input_dev *dev)
68 {
69         struct ar1021_i2c *ar1021 = input_get_drvdata(dev);
70         struct i2c_client *client = ar1021->client;
71
72         disable_irq(client->irq);
73 }
74
75 static int ar1021_i2c_probe(struct i2c_client *client,
76                                      const struct i2c_device_id *id)
77 {
78         struct ar1021_i2c *ar1021;
79         struct input_dev *input;
80         int error;
81
82         if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
83                 dev_err(&client->dev, "i2c_check_functionality error\n");
84                 return -ENXIO;
85         }
86
87         ar1021 = devm_kzalloc(&client->dev, sizeof(*ar1021), GFP_KERNEL);
88         if (!ar1021)
89                 return -ENOMEM;
90
91         input = devm_input_allocate_device(&client->dev);
92         if (!input)
93                 return -ENOMEM;
94
95         ar1021->client = client;
96         ar1021->input = input;
97
98         input->name = "ar1021 I2C Touchscreen";
99         input->id.bustype = BUS_I2C;
100         input->dev.parent = &client->dev;
101         input->open = ar1021_i2c_open;
102         input->close = ar1021_i2c_close;
103
104         input_set_capability(input, EV_KEY, BTN_TOUCH);
105         input_set_abs_params(input, ABS_X, 0, AR1021_MAX_X, 0, 0);
106         input_set_abs_params(input, ABS_Y, 0, AR1021_MAX_Y, 0, 0);
107
108         input_set_drvdata(input, ar1021);
109
110         error = devm_request_threaded_irq(&client->dev, client->irq,
111                                           NULL, ar1021_i2c_irq,
112                                           IRQF_TRIGGER_RISING | IRQF_ONESHOT,
113                                           "ar1021_i2c", ar1021);
114         if (error) {
115                 dev_err(&client->dev,
116                         "Failed to enable IRQ, error: %d\n", error);
117                 return error;
118         }
119
120         /* Disable the IRQ, we'll enable it in ar1021_i2c_open() */
121         disable_irq(client->irq);
122
123         error = input_register_device(ar1021->input);
124         if (error) {
125                 dev_err(&client->dev,
126                         "Failed to register input device, error: %d\n", error);
127                 return error;
128         }
129
130         i2c_set_clientdata(client, ar1021);
131         return 0;
132 }
133
134 static int __maybe_unused ar1021_i2c_suspend(struct device *dev)
135 {
136         struct i2c_client *client = to_i2c_client(dev);
137
138         disable_irq(client->irq);
139
140         return 0;
141 }
142
143 static int __maybe_unused ar1021_i2c_resume(struct device *dev)
144 {
145         struct i2c_client *client = to_i2c_client(dev);
146
147         enable_irq(client->irq);
148
149         return 0;
150 }
151
152 static SIMPLE_DEV_PM_OPS(ar1021_i2c_pm, ar1021_i2c_suspend, ar1021_i2c_resume);
153
154 static const struct i2c_device_id ar1021_i2c_id[] = {
155         { "ar1021", 0 },
156         { },
157 };
158 MODULE_DEVICE_TABLE(i2c, ar1021_i2c_id);
159
160 static const struct of_device_id ar1021_i2c_of_match[] = {
161         { .compatible = "microchip,ar1021-i2c", },
162         { }
163 };
164 MODULE_DEVICE_TABLE(of, ar1021_i2c_of_match);
165
166 static struct i2c_driver ar1021_i2c_driver = {
167         .driver = {
168                 .name   = "ar1021_i2c",
169                 .pm     = &ar1021_i2c_pm,
170                 .of_match_table = ar1021_i2c_of_match,
171         },
172
173         .probe          = ar1021_i2c_probe,
174         .id_table       = ar1021_i2c_id,
175 };
176 module_i2c_driver(ar1021_i2c_driver);
177
178 MODULE_AUTHOR("Christian Gmeiner <christian.gmeiner@gmail.com>");
179 MODULE_DESCRIPTION("Microchip AR1021 I2C Driver");
180 MODULE_LICENSE("GPL");