1/*
2 * Touch Screen driver for Renesas MIGO-R Platform
3 *
4 * Copyright (c) 2008 Magnus Damm
5 * Copyright (c) 2007 Ujjwal Pande <ujjwal@kenati.com>,
6 *  Kenati Technologies Pvt Ltd.
7 *
8 * This file is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU  General Public
10 * License as published by the Free Software Foundation; either
11 * version 2 of the License, or (at your option) any later version.
12 *
13 * This file is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
16 *  General Public License for more details.
17 *
18 * You should have received a copy of the GNU General Public
19 * License along with this library; if not, write to the Free Software
20 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
21 */
22#include <linux/module.h>
23#include <linux/kernel.h>
24#include <linux/input.h>
25#include <linux/interrupt.h>
26#include <linux/pm.h>
27#include <linux/slab.h>
28#include <asm/io.h>
29#include <linux/i2c.h>
30#include <linux/timer.h>
31
32#define EVENT_PENDOWN 1
33#define EVENT_REPEAT  2
34#define EVENT_PENUP   3
35
36struct migor_ts_priv {
37	struct i2c_client *client;
38	struct input_dev *input;
39	int irq;
40};
41
42static const u_int8_t migor_ts_ena_seq[17] = { 0x33, 0x22, 0x11,
43					       0x01, 0x06, 0x07, };
44static const u_int8_t migor_ts_dis_seq[17] = { };
45
46static irqreturn_t migor_ts_isr(int irq, void *dev_id)
47{
48	struct migor_ts_priv *priv = dev_id;
49	unsigned short xpos, ypos;
50	unsigned char event;
51	u_int8_t buf[16];
52
53	/*
54	 * The touch screen controller chip is hooked up to the CPU
55	 * using I2C and a single interrupt line. The interrupt line
56	 * is pulled low whenever someone taps the screen. To deassert
57	 * the interrupt line we need to acknowledge the interrupt by
58	 * communicating with the controller over the slow i2c bus.
59	 *
60	 * Since I2C bus controller may sleep we are using threaded
61	 * IRQ here.
62	 */
63
64	memset(buf, 0, sizeof(buf));
65
66	/* Set Index 0 */
67	buf[0] = 0;
68	if (i2c_master_send(priv->client, buf, 1) != 1) {
69		dev_err(&priv->client->dev, "Unable to write i2c index\n");
70		goto out;
71	}
72
73	/* Now do Page Read */
74	if (i2c_master_recv(priv->client, buf, sizeof(buf)) != sizeof(buf)) {
75		dev_err(&priv->client->dev, "Unable to read i2c page\n");
76		goto out;
77	}
78
79	ypos = ((buf[9] & 0x03) << 8 | buf[8]);
80	xpos = ((buf[11] & 0x03) << 8 | buf[10]);
81	event = buf[12];
82
83	switch (event) {
84	case EVENT_PENDOWN:
85	case EVENT_REPEAT:
86		input_report_key(priv->input, BTN_TOUCH, 1);
87		input_report_abs(priv->input, ABS_X, ypos); /*X-Y swap*/
88		input_report_abs(priv->input, ABS_Y, xpos);
89		input_sync(priv->input);
90		break;
91
92	case EVENT_PENUP:
93		input_report_key(priv->input, BTN_TOUCH, 0);
94		input_sync(priv->input);
95		break;
96	}
97
98 out:
99	return IRQ_HANDLED;
100}
101
102static int migor_ts_open(struct input_dev *dev)
103{
104	struct migor_ts_priv *priv = input_get_drvdata(dev);
105	struct i2c_client *client = priv->client;
106	int count;
107
108	/* enable controller */
109	count = i2c_master_send(client, migor_ts_ena_seq,
110				sizeof(migor_ts_ena_seq));
111	if (count != sizeof(migor_ts_ena_seq)) {
112		dev_err(&client->dev, "Unable to enable touchscreen.\n");
113		return -ENXIO;
114	}
115
116	return 0;
117}
118
119static void migor_ts_close(struct input_dev *dev)
120{
121	struct migor_ts_priv *priv = input_get_drvdata(dev);
122	struct i2c_client *client = priv->client;
123
124	disable_irq(priv->irq);
125
126	/* disable controller */
127	i2c_master_send(client, migor_ts_dis_seq, sizeof(migor_ts_dis_seq));
128
129	enable_irq(priv->irq);
130}
131
132static int migor_ts_probe(struct i2c_client *client,
133			  const struct i2c_device_id *idp)
134{
135	struct migor_ts_priv *priv;
136	struct input_dev *input;
137	int error;
138
139	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
140	input = input_allocate_device();
141	if (!priv || !input) {
142		dev_err(&client->dev, "failed to allocate memory\n");
143		error = -ENOMEM;
144		goto err_free_mem;
145	}
146
147	priv->client = client;
148	priv->input = input;
149	priv->irq = client->irq;
150
151	input->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
152
153	__set_bit(BTN_TOUCH, input->keybit);
154
155	input_set_abs_params(input, ABS_X, 95, 955, 0, 0);
156	input_set_abs_params(input, ABS_Y, 85, 935, 0, 0);
157
158	input->name = client->name;
159	input->id.bustype = BUS_I2C;
160	input->dev.parent = &client->dev;
161
162	input->open = migor_ts_open;
163	input->close = migor_ts_close;
164
165	input_set_drvdata(input, priv);
166
167	error = request_threaded_irq(priv->irq, NULL, migor_ts_isr,
168                                     IRQF_TRIGGER_LOW | IRQF_ONESHOT,
169                                     client->name, priv);
170	if (error) {
171		dev_err(&client->dev, "Unable to request touchscreen IRQ.\n");
172		goto err_free_mem;
173	}
174
175	error = input_register_device(input);
176	if (error)
177		goto err_free_irq;
178
179	i2c_set_clientdata(client, priv);
180	device_init_wakeup(&client->dev, 1);
181
182	return 0;
183
184 err_free_irq:
185	free_irq(priv->irq, priv);
186 err_free_mem:
187	input_free_device(input);
188	kfree(priv);
189	return error;
190}
191
192static int migor_ts_remove(struct i2c_client *client)
193{
194	struct migor_ts_priv *priv = i2c_get_clientdata(client);
195
196	free_irq(priv->irq, priv);
197	input_unregister_device(priv->input);
198	kfree(priv);
199
200	dev_set_drvdata(&client->dev, NULL);
201
202	return 0;
203}
204
205static int migor_ts_suspend(struct device *dev)
206{
207	struct i2c_client *client = to_i2c_client(dev);
208	struct migor_ts_priv *priv = i2c_get_clientdata(client);
209
210	if (device_may_wakeup(&client->dev))
211		enable_irq_wake(priv->irq);
212
213	return 0;
214}
215
216static int migor_ts_resume(struct device *dev)
217{
218	struct i2c_client *client = to_i2c_client(dev);
219	struct migor_ts_priv *priv = i2c_get_clientdata(client);
220
221	if (device_may_wakeup(&client->dev))
222		disable_irq_wake(priv->irq);
223
224	return 0;
225}
226
227static SIMPLE_DEV_PM_OPS(migor_ts_pm, migor_ts_suspend, migor_ts_resume);
228
229static const struct i2c_device_id migor_ts_id[] = {
230	{ "migor_ts", 0 },
231	{ }
232};
233MODULE_DEVICE_TABLE(i2c, migor_ts);
234
235static struct i2c_driver migor_ts_driver = {
236	.driver = {
237		.name = "migor_ts",
238		.pm = &migor_ts_pm,
239	},
240	.probe = migor_ts_probe,
241	.remove = migor_ts_remove,
242	.id_table = migor_ts_id,
243};
244
245module_i2c_driver(migor_ts_driver);
246
247MODULE_DESCRIPTION("MigoR Touchscreen driver");
248MODULE_AUTHOR("Magnus Damm <damm@opensource.se>");
249MODULE_LICENSE("GPL");
250