summaryrefslogtreecommitdiffstats
path: root/drivers/input/touchscreen/st1232.c
blob: 11ff32c6802506a8deedfe460010c9974a046de6 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
// SPDX-License-Identifier: GPL-2.0
/*
 * ST1232 Touchscreen Controller Driver
 *
 * Copyright (C) 2010 Renesas Solutions Corp.
 *	Tony SIM <chinyeow.sim.xt@renesas.com>
 *
 * Using code from:
 *  - android.git.kernel.org: projects/kernel/common.git: synaptics_i2c_rmi.c
 *	Copyright (C) 2007 Google, Inc.
 */

#include <linux/delay.h>
#include <linux/gpio.h>
#include <linux/i2c.h>
#include <linux/input.h>
#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_gpio.h>
#include <linux/pm_qos.h>
#include <linux/slab.h>
#include <linux/types.h>

#define ST1232_TS_NAME	"st1232-ts"

#define MIN_X		0x00
#define MIN_Y		0x00
#define MAX_X		0x31f	/* (800 - 1) */
#define MAX_Y		0x1df	/* (480 - 1) */
#define MAX_AREA	0xff
#define MAX_FINGERS	2

struct st1232_ts_finger {
	u16 x;
	u16 y;
	u8 t;
	bool is_valid;
};

struct st1232_ts_data {
	struct i2c_client *client;
	struct input_dev *input_dev;
	struct st1232_ts_finger finger[MAX_FINGERS];
	struct dev_pm_qos_request low_latency_req;
	int reset_gpio;
};

static int st1232_ts_read_data(struct st1232_ts_data *ts)
{
	struct st1232_ts_finger *finger = ts->finger;
	struct i2c_client *client = ts->client;
	struct i2c_msg msg[2];
	int error;
	u8 start_reg;
	u8 buf[10];

	/* read touchscreen data from ST1232 */
	msg[0].addr = client->addr;
	msg[0].flags = 0;
	msg[0].len = 1;
	msg[0].buf = &start_reg;
	start_reg = 0x10;

	msg[1].addr = ts->client->addr;
	msg[1].flags = I2C_M_RD;
	msg[1].len = sizeof(buf);
	msg[1].buf = buf;

	error = i2c_transfer(client->adapter, msg, 2);
	if (error < 0)
		return error;

	/* get "valid" bits */
	finger[0].is_valid = buf[2] >> 7;
	finger[1].is_valid = buf[5] >> 7;

	/* get xy coordinate */
	if (finger[0].is_valid) {
		finger[0].x = ((buf[2] & 0x0070) << 4) | buf[3];
		finger[0].y = ((buf[2] & 0x0007) << 8) | buf[4];
		finger[0].t = buf[8];
	}

	if (finger[1].is_valid) {
		finger[1].x = ((buf[5] & 0x0070) << 4) | buf[6];
		finger[1].y = ((buf[5] & 0x0007) << 8) | buf[7];
		finger[1].t = buf[9];
	}

	return 0;
}

static irqreturn_t st1232_ts_irq_handler(int irq, void *dev_id)
{
	struct st1232_ts_data *ts = dev_id;
	struct st1232_ts_finger *finger = ts->finger;
	struct input_dev *input_dev = ts->input_dev;
	int count = 0;
	int i, ret;

	ret = st1232_ts_read_data(ts);
	if (ret < 0)
		goto end;

	/* multi touch protocol */
	for (i = 0; i < MAX_FINGERS; i++) {
		if (!finger[i].is_valid)
			continue;

		input_report_abs(input_dev, ABS_MT_TOUCH_MAJOR, finger[i].t);
		input_report_abs(input_dev, ABS_MT_POSITION_X, finger[i].x);
		input_report_abs(input_dev, ABS_MT_POSITION_Y, finger[i].y);
		input_mt_sync(input_dev);
		count++;
	}

	/* SYN_MT_REPORT only if no contact */
	if (!count) {
		input_mt_sync(input_dev);
		if (ts->low_latency_req.dev) {
			dev_pm_qos_remove_request(&ts->low_latency_req);
			ts->low_latency_req.dev = NULL;
		}
	} else if (!ts->low_latency_req.dev) {
		/* First contact, request 100 us latency. */
		dev_pm_qos_add_ancestor_request(&ts->client->dev,
						&ts->low_latency_req,
						DEV_PM_QOS_RESUME_LATENCY, 100);
	}

	/* SYN_REPORT */
	input_sync(input_dev);

end:
	return IRQ_HANDLED;
}

static void st1232_ts_power(struct st1232_ts_data *ts, bool poweron)
{
	if (gpio_is_valid(ts->reset_gpio))
		gpio_direction_output(ts->reset_gpio, poweron);
}

static int st1232_ts_probe(struct i2c_client *client,
			   const struct i2c_device_id *id)
{
	struct st1232_ts_data *ts;
	struct input_dev *input_dev;
	int error;

	if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
		dev_err(&client->dev, "need I2C_FUNC_I2C\n");
		return -EIO;
	}

	if (!client->irq) {
		dev_err(&client->dev, "no IRQ?\n");
		return -EINVAL;
	}

	ts = devm_kzalloc(&client->dev, sizeof(*ts), GFP_KERNEL);
	if (!ts)
		return -ENOMEM;

	input_dev = devm_input_allocate_device(&client->dev);
	if (!input_dev)
		return -ENOMEM;

	ts->client = client;
	ts->input_dev = input_dev;

	ts->reset_gpio = of_get_gpio(client->dev.of_node, 0);
	if (gpio_is_valid(ts->reset_gpio)) {
		error = devm_gpio_request(&client->dev, ts->reset_gpio, NULL);
		if (error) {
			dev_err(&client->dev,
				"Unable to request GPIO pin %d.\n",
				ts->reset_gpio);
				return error;
		}
	}

	st1232_ts_power(ts, true);

	input_dev->name = "st1232-touchscreen";
	input_dev->id.bustype = BUS_I2C;
	input_dev->dev.parent = &client->dev;

	__set_bit(INPUT_PROP_DIRECT, input_dev->propbit);
	__set_bit(EV_SYN, input_dev->evbit);
	__set_bit(EV_KEY, input_dev->evbit);
	__set_bit(EV_ABS, input_dev->evbit);

	input_set_abs_params(input_dev, ABS_MT_TOUCH_MAJOR, 0, MAX_AREA, 0, 0);
	input_set_abs_params(input_dev, ABS_MT_POSITION_X, MIN_X, MAX_X, 0, 0);
	input_set_abs_params(input_dev, ABS_MT_POSITION_Y, MIN_Y, MAX_Y, 0, 0);

	error = devm_request_threaded_irq(&client->dev, client->irq,
					  NULL, st1232_ts_irq_handler,
					  IRQF_ONESHOT,
					  client->name, ts);
	if (error) {
		dev_err(&client->dev, "Failed to register interrupt\n");
		return error;
	}

	error = input_register_device(ts->input_dev);
	if (error) {
		dev_err(&client->dev, "Unable to register %s input device\n",
			input_dev->name);
		return error;
	}

	i2c_set_clientdata(client, ts);
	device_init_wakeup(&client->dev, 1);

	return 0;
}

static int st1232_ts_remove(struct i2c_client *client)
{
	struct st1232_ts_data *ts = i2c_get_clientdata(client);

	st1232_ts_power(ts, false);

	return 0;
}

static int __maybe_unused st1232_ts_suspend(struct device *dev)
{
	struct i2c_client *client = to_i2c_client(dev);
	struct st1232_ts_data *ts = i2c_get_clientdata(client);

	if (device_may_wakeup(&client->dev)) {
		enable_irq_wake(client->irq);
	} else {
		disable_irq(client->irq);
		st1232_ts_power(ts, false);
	}

	return 0;
}

static int __maybe_unused st1232_ts_resume(struct device *dev)
{
	struct i2c_client *client = to_i2c_client(dev);
	struct st1232_ts_data *ts = i2c_get_clientdata(client);

	if (device_may_wakeup(&client->dev)) {
		disable_irq_wake(client->irq);
	} else {
		st1232_ts_power(ts, true);
		enable_irq(client->irq);
	}

	return 0;
}

static SIMPLE_DEV_PM_OPS(st1232_ts_pm_ops,
			 st1232_ts_suspend, st1232_ts_resume);

static const struct i2c_device_id st1232_ts_id[] = {
	{ ST1232_TS_NAME, 0 },
	{ }
};
MODULE_DEVICE_TABLE(i2c, st1232_ts_id);

static const struct of_device_id st1232_ts_dt_ids[] = {
	{ .compatible = "sitronix,st1232", },
	{ }
};
MODULE_DEVICE_TABLE(of, st1232_ts_dt_ids);

static struct i2c_driver st1232_ts_driver = {
	.probe		= st1232_ts_probe,
	.remove		= st1232_ts_remove,
	.id_table	= st1232_ts_id,
	.driver = {
		.name	= ST1232_TS_NAME,
		.of_match_table = st1232_ts_dt_ids,
		.pm	= &st1232_ts_pm_ops,
	},
};

module_i2c_driver(st1232_ts_driver);

MODULE_AUTHOR("Tony SIM <chinyeow.sim.xt@renesas.com>");
MODULE_DESCRIPTION("SITRONIX ST1232 Touchscreen Controller Driver");
MODULE_LICENSE("GPL v2");