summaryrefslogtreecommitdiffstats
path: root/drivers/input/keyboard/qt1070.c
blob: 9fcce18b1d656057a4cc30cc3e30bb63dac28c2f (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
// SPDX-License-Identifier: GPL-2.0-or-later
/*
 *  Atmel AT42QT1070 QTouch Sensor Controller
 *
 *  Copyright (C) 2011 Atmel
 *
 *  Authors: Bo Shen <voice.shen@atmel.com>
 *
 *  Base on AT42QT2160 driver by:
 *  Raphael Derosso Pereira <raphaelpereira@gmail.com>
 *  Copyright (C) 2009
 */
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/i2c.h>
#include <linux/input.h>
#include <linux/slab.h>
#include <linux/irq.h>
#include <linux/interrupt.h>
#include <linux/jiffies.h>
#include <linux/delay.h>

/* Address for each register */
#define CHIP_ID            0x00
#define QT1070_CHIP_ID     0x2E

#define FW_VERSION         0x01
#define QT1070_FW_VERSION  0x15

#define DET_STATUS         0x02

#define KEY_STATUS         0x03

/* Calibrate */
#define CALIBRATE_CMD      0x38
#define QT1070_CAL_TIME    200

/* Reset */
#define RESET              0x39
#define QT1070_RESET_TIME  255

/* AT42QT1070 support up to 7 keys */
static const unsigned short qt1070_key2code[] = {
	KEY_0, KEY_1, KEY_2, KEY_3,
	KEY_4, KEY_5, KEY_6,
};

struct qt1070_data {
	struct i2c_client *client;
	struct input_dev *input;
	unsigned int irq;
	unsigned short keycodes[ARRAY_SIZE(qt1070_key2code)];
	u8 last_keys;
};

static int qt1070_read(struct i2c_client *client, u8 reg)
{
	int ret;

	ret = i2c_smbus_read_byte_data(client, reg);
	if (ret < 0)
		dev_err(&client->dev,
			"can not read register, returned %d\n", ret);

	return ret;
}

static int qt1070_write(struct i2c_client *client, u8 reg, u8 data)
{
	int ret;

	ret = i2c_smbus_write_byte_data(client, reg, data);
	if (ret < 0)
		dev_err(&client->dev,
			"can not write register, returned %d\n", ret);

	return ret;
}

static bool qt1070_identify(struct i2c_client *client)
{
	int id, ver;

	/* Read Chip ID */
	id = qt1070_read(client, CHIP_ID);
	if (id != QT1070_CHIP_ID) {
		dev_err(&client->dev, "ID %d not supported\n", id);
		return false;
	}

	/* Read firmware version */
	ver = qt1070_read(client, FW_VERSION);
	if (ver < 0) {
		dev_err(&client->dev, "could not read the firmware version\n");
		return false;
	}

	dev_info(&client->dev, "AT42QT1070 firmware version %x\n", ver);

	return true;
}

static irqreturn_t qt1070_interrupt(int irq, void *dev_id)
{
	struct qt1070_data *data = dev_id;
	struct i2c_client *client = data->client;
	struct input_dev *input = data->input;
	int i;
	u8 new_keys, keyval, mask = 0x01;

	/* Read the detected status register, thus clearing interrupt */
	qt1070_read(client, DET_STATUS);

	/* Read which key changed */
	new_keys = qt1070_read(client, KEY_STATUS);

	for (i = 0; i < ARRAY_SIZE(qt1070_key2code); i++) {
		keyval = new_keys & mask;
		if ((data->last_keys & mask) != keyval)
			input_report_key(input, data->keycodes[i], keyval);
		mask <<= 1;
	}
	input_sync(input);

	data->last_keys = new_keys;
	return IRQ_HANDLED;
}

static int qt1070_probe(struct i2c_client *client,
				const struct i2c_device_id *id)
{
	struct qt1070_data *data;
	struct input_dev *input;
	int i;
	int err;

	err = i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_BYTE);
	if (!err) {
		dev_err(&client->dev, "%s adapter not supported\n",
			dev_driver_string(&client->adapter->dev));
		return -ENODEV;
	}

	if (!client->irq) {
		dev_err(&client->dev, "please assign the irq to this device\n");
		return -EINVAL;
	}

	/* Identify the qt1070 chip */
	if (!qt1070_identify(client))
		return -ENODEV;

	data = kzalloc(sizeof(struct qt1070_data), GFP_KERNEL);
	input = input_allocate_device();
	if (!data || !input) {
		dev_err(&client->dev, "insufficient memory\n");
		err = -ENOMEM;
		goto err_free_mem;
	}

	data->client = client;
	data->input = input;
	data->irq = client->irq;

	input->name = "AT42QT1070 QTouch Sensor";
	input->dev.parent = &client->dev;
	input->id.bustype = BUS_I2C;

	/* Add the keycode */
	input->keycode = data->keycodes;
	input->keycodesize = sizeof(data->keycodes[0]);
	input->keycodemax = ARRAY_SIZE(qt1070_key2code);

	__set_bit(EV_KEY, input->evbit);

	for (i = 0; i < ARRAY_SIZE(qt1070_key2code); i++) {
		data->keycodes[i] = qt1070_key2code[i];
		__set_bit(qt1070_key2code[i], input->keybit);
	}

	/* Calibrate device */
	qt1070_write(client, CALIBRATE_CMD, 1);
	msleep(QT1070_CAL_TIME);

	/* Soft reset */
	qt1070_write(client, RESET, 1);
	msleep(QT1070_RESET_TIME);

	err = request_threaded_irq(client->irq, NULL, qt1070_interrupt,
				   IRQF_TRIGGER_NONE | IRQF_ONESHOT,
				   client->dev.driver->name, data);
	if (err) {
		dev_err(&client->dev, "fail to request irq\n");
		goto err_free_mem;
	}

	/* Register the input device */
	err = input_register_device(data->input);
	if (err) {
		dev_err(&client->dev, "Failed to register input device\n");
		goto err_free_irq;
	}

	i2c_set_clientdata(client, data);

	/* Read to clear the chang line */
	qt1070_read(client, DET_STATUS);

	return 0;

err_free_irq:
	free_irq(client->irq, data);
err_free_mem:
	input_free_device(input);
	kfree(data);
	return err;
}

static void qt1070_remove(struct i2c_client *client)
{
	struct qt1070_data *data = i2c_get_clientdata(client);

	/* Release IRQ */
	free_irq(client->irq, data);

	input_unregister_device(data->input);
	kfree(data);
}

#ifdef CONFIG_PM_SLEEP
static int qt1070_suspend(struct device *dev)
{
	struct i2c_client *client = to_i2c_client(dev);
	struct qt1070_data *data = i2c_get_clientdata(client);

	if (device_may_wakeup(dev))
		enable_irq_wake(data->irq);

	return 0;
}

static int qt1070_resume(struct device *dev)
{
	struct i2c_client *client = to_i2c_client(dev);
	struct qt1070_data *data = i2c_get_clientdata(client);

	if (device_may_wakeup(dev))
		disable_irq_wake(data->irq);

	return 0;
}
#endif

static SIMPLE_DEV_PM_OPS(qt1070_pm_ops, qt1070_suspend, qt1070_resume);

static const struct i2c_device_id qt1070_id[] = {
	{ "qt1070", 0 },
	{ },
};
MODULE_DEVICE_TABLE(i2c, qt1070_id);

#ifdef CONFIG_OF
static const struct of_device_id qt1070_of_match[] = {
	{ .compatible = "qt1070", },
	{ },
};
MODULE_DEVICE_TABLE(of, qt1070_of_match);
#endif

static struct i2c_driver qt1070_driver = {
	.driver	= {
		.name	= "qt1070",
		.of_match_table = of_match_ptr(qt1070_of_match),
		.pm	= &qt1070_pm_ops,
	},
	.id_table	= qt1070_id,
	.probe		= qt1070_probe,
	.remove		= qt1070_remove,
};

module_i2c_driver(qt1070_driver);

MODULE_AUTHOR("Bo Shen <voice.shen@atmel.com>");
MODULE_DESCRIPTION("Driver for AT42QT1070 QTouch sensor");
MODULE_LICENSE("GPL");