Input: add support for Semtech SX8654 I2C touchscreen controller
[muen/linux.git] / drivers / input / touchscreen / sx8654.c
1 /*
2  * Driver for Semtech SX8654 I2C touchscreen controller.
3  *
4  * Copyright (c) 2015 Armadeus Systems
5  *      S├ębastien Szymanski <sebastien.szymanski@armadeus.com>
6  *
7  * Using code from:
8  *  - sx865x.c
9  *      Copyright (c) 2013 U-MoBo Srl
10  *      Pierluigi Passaro <p.passaro@u-mobo.com>
11  *  - sx8650.c
12  *      Copyright (c) 2009 Wayne Roberts
13  *  - tsc2007.c
14  *      Copyright (c) 2008 Kwangwoo Lee
15  *  - ads7846.c
16  *      Copyright (c) 2005 David Brownell
17  *      Copyright (c) 2006 Nokia Corporation
18  *  - corgi_ts.c
19  *      Copyright (C) 2004-2005 Richard Purdie
20  *  - omap_ts.[hc], ads7846.h, ts_osk.c
21  *      Copyright (C) 2002 MontaVista Software
22  *      Copyright (C) 2004 Texas Instruments
23  *      Copyright (C) 2005 Dirk Behme
24  *
25  *  This program is free software; you can redistribute it and/or modify
26  *  it under the terms of the GNU General Public License version 2 as
27  *  published by the Free Software Foundation.
28  */
29
30 #include <linux/input.h>
31 #include <linux/module.h>
32 #include <linux/of.h>
33 #include <linux/i2c.h>
34 #include <linux/interrupt.h>
35 #include <linux/irq.h>
36
37 /* register addresses */
38 #define I2C_REG_TOUCH0                  0x00
39 #define I2C_REG_TOUCH1                  0x01
40 #define I2C_REG_CHANMASK                0x04
41 #define I2C_REG_IRQMASK                 0x22
42 #define I2C_REG_IRQSRC                  0x23
43 #define I2C_REG_SOFTRESET               0x3f
44
45 /* commands */
46 #define CMD_READ_REGISTER               0x40
47 #define CMD_MANUAL                      0xc0
48 #define CMD_PENTRG                      0xe0
49
50 /* value for I2C_REG_SOFTRESET */
51 #define SOFTRESET_VALUE                 0xde
52
53 /* bits for I2C_REG_IRQSRC */
54 #define IRQ_PENTOUCH_TOUCHCONVDONE      0x08
55 #define IRQ_PENRELEASE                  0x04
56
57 /* bits for RegTouch1 */
58 #define CONDIRQ                         0x20
59 #define FILT_7SA                        0x03
60
61 /* bits for I2C_REG_CHANMASK */
62 #define CONV_X                          0x80
63 #define CONV_Y                          0x40
64
65 /* coordinates rate: higher nibble of CTRL0 register */
66 #define RATE_MANUAL                     0x00
67 #define RATE_5000CPS                    0xf0
68
69 /* power delay: lower nibble of CTRL0 register */
70 #define POWDLY_1_1MS                    0x0b
71
72 #define MAX_12BIT                       ((1 << 12) - 1)
73
74 struct sx8654 {
75         struct input_dev *input;
76         struct i2c_client *client;
77 };
78
79 static irqreturn_t sx8654_irq(int irq, void *handle)
80 {
81         struct sx8654 *sx8654 = handle;
82         u8 irqsrc;
83         u8 data[4];
84         unsigned int x, y;
85         int retval;
86
87         irqsrc = i2c_smbus_read_byte_data(sx8654->client,
88                                           CMD_READ_REGISTER | I2C_REG_IRQSRC);
89         dev_dbg(&sx8654->client->dev, "irqsrc = 0x%x", irqsrc);
90
91         if (irqsrc < 0)
92                 goto out;
93
94         if (irqsrc & IRQ_PENRELEASE) {
95                 dev_dbg(&sx8654->client->dev, "pen release interrupt");
96
97                 input_report_key(sx8654->input, BTN_TOUCH, 0);
98                 input_sync(sx8654->input);
99         }
100
101         if (irqsrc & IRQ_PENTOUCH_TOUCHCONVDONE) {
102                 dev_dbg(&sx8654->client->dev, "pen touch interrupt");
103
104                 retval = i2c_master_recv(sx8654->client, data, sizeof(data));
105                 if (retval != sizeof(data))
106                         goto out;
107
108                 /* invalid data */
109                 if (unlikely(data[0] & 0x80 || data[2] & 0x80))
110                         goto out;
111
112                 x = ((data[0] & 0xf) << 8) | (data[1]);
113                 y = ((data[2] & 0xf) << 8) | (data[3]);
114
115                 input_report_abs(sx8654->input, ABS_X, x);
116                 input_report_abs(sx8654->input, ABS_Y, y);
117                 input_report_key(sx8654->input, BTN_TOUCH, 1);
118                 input_sync(sx8654->input);
119
120                 dev_dbg(&sx8654->client->dev, "point(%4d,%4d)\n", x, y);
121         }
122
123 out:
124         return IRQ_HANDLED;
125 }
126
127 static int sx8654_open(struct input_dev *dev)
128 {
129         struct sx8654 *sx8654 = input_get_drvdata(dev);
130         struct i2c_client *client = sx8654->client;
131         int error;
132
133         /* enable pen trigger mode */
134         error = i2c_smbus_write_byte_data(client, I2C_REG_TOUCH0,
135                                           RATE_5000CPS | POWDLY_1_1MS);
136         if (error) {
137                 dev_err(&client->dev, "writing to I2C_REG_TOUCH0 failed");
138                 return error;
139         }
140
141         error = i2c_smbus_write_byte(client, CMD_PENTRG);
142         if (error) {
143                 dev_err(&client->dev, "writing command CMD_PENTRG failed");
144                 return error;
145         }
146
147         enable_irq(client->irq);
148
149         return 0;
150 }
151
152 static void sx8654_close(struct input_dev *dev)
153 {
154         struct sx8654 *sx8654 = input_get_drvdata(dev);
155         struct i2c_client *client = sx8654->client;
156         int error;
157
158         disable_irq(client->irq);
159
160         /* enable manual mode mode */
161         error = i2c_smbus_write_byte(client, CMD_MANUAL);
162         if (error) {
163                 dev_err(&client->dev, "writing command CMD_MANUAL failed");
164                 return;
165         }
166
167         error = i2c_smbus_write_byte_data(client, I2C_REG_TOUCH0, 0);
168         if (error) {
169                 dev_err(&client->dev, "writing to I2C_REG_TOUCH0 failed");
170                 return;
171         }
172 }
173
174 static int sx8654_probe(struct i2c_client *client,
175                         const struct i2c_device_id *id)
176 {
177         struct sx8654 *sx8654;
178         struct input_dev *input;
179         int error;
180
181         if (!i2c_check_functionality(client->adapter,
182                                      I2C_FUNC_SMBUS_READ_WORD_DATA))
183                 return -ENXIO;
184
185         sx8654 = devm_kzalloc(&client->dev, sizeof(*sx8654), GFP_KERNEL);
186         if (!sx8654)
187                 return -ENOMEM;
188
189         input = devm_input_allocate_device(&client->dev);
190         if (!sx8654)
191                 return -ENOMEM;
192
193         input->name = "SX8654 I2C Touchscreen";
194         input->id.bustype = BUS_I2C;
195         input->dev.parent = &client->dev;
196         input->open = sx8654_open;
197         input->close = sx8654_close;
198
199         __set_bit(INPUT_PROP_DIRECT, input->propbit);
200         input_set_capability(input, EV_KEY, BTN_TOUCH);
201         input_set_abs_params(input, ABS_X, 0, MAX_12BIT, 0, 0);
202         input_set_abs_params(input, ABS_Y, 0, MAX_12BIT, 0, 0);
203
204         sx8654->client = client;
205         sx8654->input = input;
206
207         input_set_drvdata(sx8654->input, sx8654);
208
209         error = i2c_smbus_write_byte_data(client, I2C_REG_SOFTRESET,
210                                           SOFTRESET_VALUE);
211         if (error) {
212                 dev_err(&client->dev, "writing softreset value failed");
213                 return error;
214         }
215
216         error = i2c_smbus_write_byte_data(client, I2C_REG_CHANMASK,
217                                           CONV_X | CONV_Y);
218         if (error) {
219                 dev_err(&client->dev, "writing to I2C_REG_CHANMASK failed");
220                 return error;
221         }
222
223         error = i2c_smbus_write_byte_data(client, I2C_REG_IRQMASK,
224                                           IRQ_PENTOUCH_TOUCHCONVDONE |
225                                                 IRQ_PENRELEASE);
226         if (error) {
227                 dev_err(&client->dev, "writing to I2C_REG_IRQMASK failed");
228                 return error;
229         }
230
231         error = i2c_smbus_write_byte_data(client, I2C_REG_TOUCH1,
232                                           CONDIRQ | FILT_7SA);
233         if (error) {
234                 dev_err(&client->dev, "writing to I2C_REG_TOUCH1 failed");
235                 return error;
236         }
237
238         error = devm_request_threaded_irq(&client->dev, client->irq,
239                                           NULL, sx8654_irq,
240                                           IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
241                                           client->name, sx8654);
242         if (error) {
243                 dev_err(&client->dev,
244                         "Failed to enable IRQ %d, error: %d\n",
245                         client->irq, error);
246                 return error;
247         }
248
249         /* Disable the IRQ, we'll enable it in sx8654_open() */
250         disable_irq(client->irq);
251
252         error = input_register_device(sx8654->input);
253         if (error)
254                 return error;
255
256         i2c_set_clientdata(client, sx8654);
257         return 0;
258 }
259
260 #ifdef CONFIG_OF
261 static const struct of_device_id sx8654_of_match[] = {
262         { .compatible = "semtech,sx8654", },
263         { },
264 };
265 MODULE_DEVICE_TABLE(of, sx8654_of_match);
266 #endif
267
268 static const struct i2c_device_id sx8654_id_table[] = {
269         { "semtech_sx8654", 0 },
270         { },
271 };
272 MODULE_DEVICE_TABLE(i2c, sx8654_id_table);
273
274 static struct i2c_driver sx8654_driver = {
275         .driver = {
276                 .name = "sx8654",
277                 .of_match_table = of_match_ptr(sx8654_of_match),
278         },
279         .id_table = sx8654_id_table,
280         .probe = sx8654_probe,
281 };
282 module_i2c_driver(sx8654_driver);
283
284 MODULE_AUTHOR("S├ębastien Szymanski <sebastien.szymanski@armadeus.com>");
285 MODULE_DESCRIPTION("Semtech SX8654 I2C Touchscreen Driver");
286 MODULE_LICENSE("GPL");