summaryrefslogtreecommitdiffstats
path: root/drivers/input/touchscreen/wacom_i2c.c
blob: f017af8c2aa3fd80a9e51b87cda309a9b29f1365 (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
// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Wacom Penabled Driver for I2C
 *
 * Copyright (c) 2011 - 2013 Tatsunosuke Tobita, Wacom.
 * <tobita.tatsunosuke@wacom.co.jp>
 */

#include <linux/module.h>
#include <linux/input.h>
#include <linux/i2c.h>
#include <linux/slab.h>
#include <linux/irq.h>
#include <linux/interrupt.h>
#include <linux/gpio.h>
#include <asm/unaligned.h>

#define WACOM_CMD_QUERY0	0x04
#define WACOM_CMD_QUERY1	0x00
#define WACOM_CMD_QUERY2	0x33
#define WACOM_CMD_QUERY3	0x02
#define WACOM_CMD_THROW0	0x05
#define WACOM_CMD_THROW1	0x00
#define WACOM_QUERY_SIZE	19

struct wacom_features {
	int x_max;
	int y_max;
	int pressure_max;
	char fw_version;
};

struct wacom_i2c {
	struct i2c_client *client;
	struct input_dev *input;
	u8 data[WACOM_QUERY_SIZE];
	bool prox;
	int tool;
};

static int wacom_query_device(struct i2c_client *client,
			      struct wacom_features *features)
{
	int ret;
	u8 cmd1[] = { WACOM_CMD_QUERY0, WACOM_CMD_QUERY1,
			WACOM_CMD_QUERY2, WACOM_CMD_QUERY3 };
	u8 cmd2[] = { WACOM_CMD_THROW0, WACOM_CMD_THROW1 };
	u8 data[WACOM_QUERY_SIZE];
	struct i2c_msg msgs[] = {
		{
			.addr = client->addr,
			.flags = 0,
			.len = sizeof(cmd1),
			.buf = cmd1,
		},
		{
			.addr = client->addr,
			.flags = 0,
			.len = sizeof(cmd2),
			.buf = cmd2,
		},
		{
			.addr = client->addr,
			.flags = I2C_M_RD,
			.len = sizeof(data),
			.buf = data,
		},
	};

	ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
	if (ret < 0)
		return ret;
	if (ret != ARRAY_SIZE(msgs))
		return -EIO;

	features->x_max = get_unaligned_le16(&data[3]);
	features->y_max = get_unaligned_le16(&data[5]);
	features->pressure_max = get_unaligned_le16(&data[11]);
	features->fw_version = get_unaligned_le16(&data[13]);

	dev_dbg(&client->dev,
		"x_max:%d, y_max:%d, pressure:%d, fw:%d\n",
		features->x_max, features->y_max,
		features->pressure_max, features->fw_version);

	return 0;
}

static irqreturn_t wacom_i2c_irq(int irq, void *dev_id)
{
	struct wacom_i2c *wac_i2c = dev_id;
	struct input_dev *input = wac_i2c->input;
	u8 *data = wac_i2c->data;
	unsigned int x, y, pressure;
	unsigned char tsw, f1, f2, ers;
	int error;

	error = i2c_master_recv(wac_i2c->client,
				wac_i2c->data, sizeof(wac_i2c->data));
	if (error < 0)
		goto out;

	tsw = data[3] & 0x01;
	ers = data[3] & 0x04;
	f1 = data[3] & 0x02;
	f2 = data[3] & 0x10;
	x = le16_to_cpup((__le16 *)&data[4]);
	y = le16_to_cpup((__le16 *)&data[6]);
	pressure = le16_to_cpup((__le16 *)&data[8]);

	if (!wac_i2c->prox)
		wac_i2c->tool = (data[3] & 0x0c) ?
			BTN_TOOL_RUBBER : BTN_TOOL_PEN;

	wac_i2c->prox = data[3] & 0x20;

	input_report_key(input, BTN_TOUCH, tsw || ers);
	input_report_key(input, wac_i2c->tool, wac_i2c->prox);
	input_report_key(input, BTN_STYLUS, f1);
	input_report_key(input, BTN_STYLUS2, f2);
	input_report_abs(input, ABS_X, x);
	input_report_abs(input, ABS_Y, y);
	input_report_abs(input, ABS_PRESSURE, pressure);
	input_sync(input);

out:
	return IRQ_HANDLED;
}

static int wacom_i2c_open(struct input_dev *dev)
{
	struct wacom_i2c *wac_i2c = input_get_drvdata(dev);
	struct i2c_client *client = wac_i2c->client;

	enable_irq(client->irq);

	return 0;
}

static void wacom_i2c_close(struct input_dev *dev)
{
	struct wacom_i2c *wac_i2c = input_get_drvdata(dev);
	struct i2c_client *client = wac_i2c->client;

	disable_irq(client->irq);
}

static int wacom_i2c_probe(struct i2c_client *client,
				     const struct i2c_device_id *id)
{
	struct wacom_i2c *wac_i2c;
	struct input_dev *input;
	struct wacom_features features = { 0 };
	int error;

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

	error = wacom_query_device(client, &features);
	if (error)
		return error;

	wac_i2c = kzalloc(sizeof(*wac_i2c), GFP_KERNEL);
	input = input_allocate_device();
	if (!wac_i2c || !input) {
		error = -ENOMEM;
		goto err_free_mem;
	}

	wac_i2c->client = client;
	wac_i2c->input = input;

	input->name = "Wacom I2C Digitizer";
	input->id.bustype = BUS_I2C;
	input->id.vendor = 0x56a;
	input->id.version = features.fw_version;
	input->dev.parent = &client->dev;
	input->open = wacom_i2c_open;
	input->close = wacom_i2c_close;

	input->evbit[0] |= BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);

	__set_bit(BTN_TOOL_PEN, input->keybit);
	__set_bit(BTN_TOOL_RUBBER, input->keybit);
	__set_bit(BTN_STYLUS, input->keybit);
	__set_bit(BTN_STYLUS2, input->keybit);
	__set_bit(BTN_TOUCH, input->keybit);

	input_set_abs_params(input, ABS_X, 0, features.x_max, 0, 0);
	input_set_abs_params(input, ABS_Y, 0, features.y_max, 0, 0);
	input_set_abs_params(input, ABS_PRESSURE,
			     0, features.pressure_max, 0, 0);

	input_set_drvdata(input, wac_i2c);

	error = request_threaded_irq(client->irq, NULL, wacom_i2c_irq,
				     IRQF_TRIGGER_LOW | IRQF_ONESHOT,
				     "wacom_i2c", wac_i2c);
	if (error) {
		dev_err(&client->dev,
			"Failed to enable IRQ, error: %d\n", error);
		goto err_free_mem;
	}

	/* Disable the IRQ, we'll enable it in wac_i2c_open() */
	disable_irq(client->irq);

	error = input_register_device(wac_i2c->input);
	if (error) {
		dev_err(&client->dev,
			"Failed to register input device, error: %d\n", error);
		goto err_free_irq;
	}

	i2c_set_clientdata(client, wac_i2c);
	return 0;

err_free_irq:
	free_irq(client->irq, wac_i2c);
err_free_mem:
	input_free_device(input);
	kfree(wac_i2c);

	return error;
}

static int wacom_i2c_remove(struct i2c_client *client)
{
	struct wacom_i2c *wac_i2c = i2c_get_clientdata(client);

	free_irq(client->irq, wac_i2c);
	input_unregister_device(wac_i2c->input);
	kfree(wac_i2c);

	return 0;
}

static int __maybe_unused wacom_i2c_suspend(struct device *dev)
{
	struct i2c_client *client = to_i2c_client(dev);

	disable_irq(client->irq);

	return 0;
}

static int __maybe_unused wacom_i2c_resume(struct device *dev)
{
	struct i2c_client *client = to_i2c_client(dev);

	enable_irq(client->irq);

	return 0;
}

static SIMPLE_DEV_PM_OPS(wacom_i2c_pm, wacom_i2c_suspend, wacom_i2c_resume);

static const struct i2c_device_id wacom_i2c_id[] = {
	{ "WAC_I2C_EMR", 0 },
	{ },
};
MODULE_DEVICE_TABLE(i2c, wacom_i2c_id);

static struct i2c_driver wacom_i2c_driver = {
	.driver	= {
		.name	= "wacom_i2c",
		.pm	= &wacom_i2c_pm,
	},

	.probe		= wacom_i2c_probe,
	.remove		= wacom_i2c_remove,
	.id_table	= wacom_i2c_id,
};
module_i2c_driver(wacom_i2c_driver);

MODULE_AUTHOR("Tatsunosuke Tobita <tobita.tatsunosuke@wacom.co.jp>");
MODULE_DESCRIPTION("WACOM EMR I2C Driver");
MODULE_LICENSE("GPL");