f9dcbd63e59826b6fa98620a36af6cce5cfd4fbc
[sfrench/cifs-2.6.git] / drivers / input / touchscreen / ar1021_i2c.c
1 /*
2  * Microchip AR1020 and 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/bitops.h>
10 #include <linux/module.h>
11 #include <linux/input.h>
12 #include <linux/of.h>
13 #include <linux/i2c.h>
14 #include <linux/irq.h>
15 #include <linux/interrupt.h>
16
17 #define AR1021_TOCUH_PKG_SIZE   5
18
19 #define AR1021_MAX_X    4095
20 #define AR1021_MAX_Y    4095
21
22 #define AR1021_CMD      0x55
23
24 #define AR1021_CMD_ENABLE_TOUCH         0x12
25
26 struct ar1021_i2c {
27         struct i2c_client *client;
28         struct input_dev *input;
29         u8 data[AR1021_TOCUH_PKG_SIZE];
30 };
31
32 static irqreturn_t ar1021_i2c_irq(int irq, void *dev_id)
33 {
34         struct ar1021_i2c *ar1021 = dev_id;
35         struct input_dev *input = ar1021->input;
36         u8 *data = ar1021->data;
37         unsigned int x, y, button;
38         int retval;
39
40         retval = i2c_master_recv(ar1021->client,
41                                  ar1021->data, sizeof(ar1021->data));
42         if (retval != sizeof(ar1021->data))
43                 goto out;
44
45         /* sync bit set ? */
46         if (!(data[0] & BIT(7)))
47                 goto out;
48
49         button = data[0] & BIT(0);
50         x = ((data[2] & 0x1f) << 7) | (data[1] & 0x7f);
51         y = ((data[4] & 0x1f) << 7) | (data[3] & 0x7f);
52
53         input_report_abs(input, ABS_X, x);
54         input_report_abs(input, ABS_Y, y);
55         input_report_key(input, BTN_TOUCH, button);
56         input_sync(input);
57
58 out:
59         return IRQ_HANDLED;
60 }
61
62 static int ar1021_i2c_open(struct input_dev *dev)
63 {
64         static const u8 cmd_enable_touch[] = {
65                 AR1021_CMD,
66                 0x01, /* number of bytes after this */
67                 AR1021_CMD_ENABLE_TOUCH
68         };
69         struct ar1021_i2c *ar1021 = input_get_drvdata(dev);
70         struct i2c_client *client = ar1021->client;
71         int error;
72
73         error = i2c_master_send(ar1021->client, cmd_enable_touch,
74                                 sizeof(cmd_enable_touch));
75         if (error < 0)
76                 return error;
77
78         enable_irq(client->irq);
79
80         return 0;
81 }
82
83 static void ar1021_i2c_close(struct input_dev *dev)
84 {
85         struct ar1021_i2c *ar1021 = input_get_drvdata(dev);
86         struct i2c_client *client = ar1021->client;
87
88         disable_irq(client->irq);
89 }
90
91 static int ar1021_i2c_probe(struct i2c_client *client,
92                             const struct i2c_device_id *id)
93 {
94         struct ar1021_i2c *ar1021;
95         struct input_dev *input;
96         int error;
97
98         if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
99                 dev_err(&client->dev, "i2c_check_functionality error\n");
100                 return -ENXIO;
101         }
102
103         ar1021 = devm_kzalloc(&client->dev, sizeof(*ar1021), GFP_KERNEL);
104         if (!ar1021)
105                 return -ENOMEM;
106
107         input = devm_input_allocate_device(&client->dev);
108         if (!input)
109                 return -ENOMEM;
110
111         ar1021->client = client;
112         ar1021->input = input;
113
114         input->name = "ar1021 I2C Touchscreen";
115         input->id.bustype = BUS_I2C;
116         input->dev.parent = &client->dev;
117         input->open = ar1021_i2c_open;
118         input->close = ar1021_i2c_close;
119
120         input_set_capability(input, EV_KEY, BTN_TOUCH);
121         input_set_abs_params(input, ABS_X, 0, AR1021_MAX_X, 0, 0);
122         input_set_abs_params(input, ABS_Y, 0, AR1021_MAX_Y, 0, 0);
123
124         input_set_drvdata(input, ar1021);
125
126         error = devm_request_threaded_irq(&client->dev, client->irq,
127                                           NULL, ar1021_i2c_irq,
128                                           IRQF_ONESHOT,
129                                           "ar1021_i2c", ar1021);
130         if (error) {
131                 dev_err(&client->dev,
132                         "Failed to enable IRQ, error: %d\n", error);
133                 return error;
134         }
135
136         /* Disable the IRQ, we'll enable it in ar1021_i2c_open() */
137         disable_irq(client->irq);
138
139         error = input_register_device(ar1021->input);
140         if (error) {
141                 dev_err(&client->dev,
142                         "Failed to register input device, error: %d\n", error);
143                 return error;
144         }
145
146         return 0;
147 }
148
149 static int __maybe_unused ar1021_i2c_suspend(struct device *dev)
150 {
151         struct i2c_client *client = to_i2c_client(dev);
152
153         disable_irq(client->irq);
154
155         return 0;
156 }
157
158 static int __maybe_unused ar1021_i2c_resume(struct device *dev)
159 {
160         struct i2c_client *client = to_i2c_client(dev);
161
162         enable_irq(client->irq);
163
164         return 0;
165 }
166
167 static SIMPLE_DEV_PM_OPS(ar1021_i2c_pm, ar1021_i2c_suspend, ar1021_i2c_resume);
168
169 static const struct i2c_device_id ar1021_i2c_id[] = {
170         { "ar1021", 0 },
171         { },
172 };
173 MODULE_DEVICE_TABLE(i2c, ar1021_i2c_id);
174
175 static const struct of_device_id ar1021_i2c_of_match[] = {
176         { .compatible = "microchip,ar1021-i2c", },
177         { }
178 };
179 MODULE_DEVICE_TABLE(of, ar1021_i2c_of_match);
180
181 static struct i2c_driver ar1021_i2c_driver = {
182         .driver = {
183                 .name   = "ar1021_i2c",
184                 .pm     = &ar1021_i2c_pm,
185                 .of_match_table = ar1021_i2c_of_match,
186         },
187
188         .probe          = ar1021_i2c_probe,
189         .id_table       = ar1021_i2c_id,
190 };
191 module_i2c_driver(ar1021_i2c_driver);
192
193 MODULE_AUTHOR("Christian Gmeiner <christian.gmeiner@gmail.com>");
194 MODULE_DESCRIPTION("Microchip AR1020 and AR1021 I2C Driver");
195 MODULE_LICENSE("GPL");