blob: 504ca11749a1896e35b489bfba4bdc6747c57e71 [file] [log] [blame]
Magnus Damm885c3162008-05-07 11:15:02 -04001/*
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 <asm/io.h>
27#include <linux/i2c.h>
28#include <linux/timer.h>
29
30#define EVENT_PENDOWN 1
31#define EVENT_REPEAT 2
32#define EVENT_PENUP 3
33
34struct migor_ts_priv {
35 struct i2c_client *client;
36 struct input_dev *input;
37 struct delayed_work work;
38 int irq;
39};
40
41static const u_int8_t migor_ts_ena_seq[17] = { 0x33, 0x22, 0x11,
42 0x01, 0x06, 0x07, };
43static const u_int8_t migor_ts_dis_seq[17] = { };
44
45static void migor_ts_poscheck(struct work_struct *work)
46{
47 struct migor_ts_priv *priv = container_of(work,
48 struct migor_ts_priv,
49 work.work);
50 unsigned short xpos, ypos;
51 unsigned char event;
52 u_int8_t buf[16];
53
54 memset(buf, 0, sizeof(buf));
55
56 /* Set Index 0 */
57 buf[0] = 0;
58 if (i2c_master_send(priv->client, buf, 1) != 1) {
59 dev_err(&priv->client->dev, "Unable to write i2c index\n");
60 goto out;
61 }
62
63 /* Now do Page Read */
64 if (i2c_master_recv(priv->client, buf, sizeof(buf)) != sizeof(buf)) {
65 dev_err(&priv->client->dev, "Unable to read i2c page\n");
66 goto out;
67 }
68
69 ypos = ((buf[9] & 0x03) << 8 | buf[8]);
70 xpos = ((buf[11] & 0x03) << 8 | buf[10]);
71 event = buf[12];
72
73 if (event == EVENT_PENDOWN || event == EVENT_REPEAT) {
74 input_report_key(priv->input, BTN_TOUCH, 1);
75 input_report_abs(priv->input, ABS_X, ypos); /*X-Y swap*/
76 input_report_abs(priv->input, ABS_Y, xpos);
77 input_sync(priv->input);
78 } else if (event == EVENT_PENUP) {
79 input_report_key(priv->input, BTN_TOUCH, 0);
80 input_sync(priv->input);
81 }
82 out:
83 enable_irq(priv->irq);
84}
85
86static irqreturn_t migor_ts_isr(int irq, void *dev_id)
87{
88 struct migor_ts_priv *priv = dev_id;
89
90 /* the touch screen controller chip is hooked up to the cpu
91 * using i2c and a single interrupt line. the interrupt line
92 * is pulled low whenever someone taps the screen. to deassert
93 * the interrupt line we need to acknowledge the interrupt by
94 * communicating with the controller over the slow i2c bus.
95 *
96 * we can't acknowledge from interrupt context since the i2c
97 * bus controller may sleep, so we just disable the interrupt
98 * here and handle the acknowledge using delayed work.
99 */
100
101 disable_irq_nosync(irq);
102 schedule_delayed_work(&priv->work, HZ / 20);
103
104 return IRQ_HANDLED;
105}
106
107
108static int migor_ts_open(struct input_dev *dev)
109{
110 struct migor_ts_priv *priv = input_get_drvdata(dev);
111 struct i2c_client *client = priv->client;
112 int count;
113
114 /* enable controller */
115 count = i2c_master_send(client, migor_ts_ena_seq,
116 sizeof(migor_ts_ena_seq));
117 if (count != sizeof(migor_ts_ena_seq)) {
118 dev_err(&client->dev, "Unable to enable touchscreen.\n");
119 return -ENXIO;
120 }
121
122 return 0;
123}
124
125static void migor_ts_close(struct input_dev *dev)
126{
127 struct migor_ts_priv *priv = input_get_drvdata(dev);
128 struct i2c_client *client = priv->client;
129
130 disable_irq(priv->irq);
131
132 /* cancel pending work and wait for migor_ts_poscheck() to finish */
133 if (cancel_delayed_work_sync(&priv->work)) {
134 /*
135 * if migor_ts_poscheck was canceled we need to enable IRQ
136 * here to balance disable done in migor_ts_isr.
137 */
138 enable_irq(priv->irq);
139 }
140
141 /* disable controller */
142 i2c_master_send(client, migor_ts_dis_seq, sizeof(migor_ts_dis_seq));
143
144 enable_irq(priv->irq);
145}
146
147static int migor_ts_probe(struct i2c_client *client,
148 const struct i2c_device_id *idp)
149{
150 struct migor_ts_priv *priv;
151 struct input_dev *input;
152 int error;
153
154 priv = kzalloc(sizeof(*priv), GFP_KERNEL);
155 if (!priv) {
156 dev_err(&client->dev, "failed to allocate driver data\n");
157 error = -ENOMEM;
158 goto err0;
159 }
160
161 dev_set_drvdata(&client->dev, priv);
162
163 input = input_allocate_device();
164 if (!input) {
165 dev_err(&client->dev, "Failed to allocate input device.\n");
166 error = -ENOMEM;
167 goto err1;
168 }
169
170 input->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
171 input->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH);
172
173 input_set_abs_params(input, ABS_X, 95, 955, 0, 0);
174 input_set_abs_params(input, ABS_Y, 85, 935, 0, 0);
175
Magnus Dammb6ce9ad2008-08-11 14:53:49 +0900176 input->name = client->name;
Magnus Damm885c3162008-05-07 11:15:02 -0400177 input->id.bustype = BUS_I2C;
178 input->dev.parent = &client->dev;
179
180 input->open = migor_ts_open;
181 input->close = migor_ts_close;
182
183 input_set_drvdata(input, priv);
184
185 priv->client = client;
186 priv->input = input;
187 INIT_DELAYED_WORK(&priv->work, migor_ts_poscheck);
188 priv->irq = client->irq;
189
190 error = input_register_device(input);
191 if (error)
192 goto err1;
193
194 error = request_irq(priv->irq, migor_ts_isr, IRQF_TRIGGER_LOW,
Magnus Dammb6ce9ad2008-08-11 14:53:49 +0900195 client->name, priv);
Magnus Damm885c3162008-05-07 11:15:02 -0400196 if (error) {
197 dev_err(&client->dev, "Unable to request touchscreen IRQ.\n");
198 goto err2;
199 }
200
201 return 0;
202
203 err2:
204 input_unregister_device(input);
205 input = NULL; /* so we dont try to free it below */
206 err1:
207 input_free_device(input);
208 kfree(priv);
209 err0:
210 dev_set_drvdata(&client->dev, NULL);
211 return error;
212}
213
214static int migor_ts_remove(struct i2c_client *client)
215{
216 struct migor_ts_priv *priv = dev_get_drvdata(&client->dev);
217
218 free_irq(priv->irq, priv);
219 input_unregister_device(priv->input);
220 kfree(priv);
221
222 dev_set_drvdata(&client->dev, NULL);
223
224 return 0;
225}
226
Magnus Dammb6ce9ad2008-08-11 14:53:49 +0900227static const struct i2c_device_id migor_ts_id[] = {
228 { "migor_ts", 0 },
229 { }
230};
231MODULE_DEVICE_TABLE(i2c, migor_ts);
232
Magnus Damm885c3162008-05-07 11:15:02 -0400233static struct i2c_driver migor_ts_driver = {
234 .driver = {
235 .name = "migor_ts",
236 },
237 .probe = migor_ts_probe,
238 .remove = migor_ts_remove,
Magnus Dammb6ce9ad2008-08-11 14:53:49 +0900239 .id_table = migor_ts_id,
Magnus Damm885c3162008-05-07 11:15:02 -0400240};
241
242static int __init migor_ts_init(void)
243{
244 return i2c_add_driver(&migor_ts_driver);
245}
246
247static void __exit migor_ts_exit(void)
248{
249 i2c_del_driver(&migor_ts_driver);
250}
251
252MODULE_DESCRIPTION("MigoR Touchscreen driver");
253MODULE_AUTHOR("Magnus Damm <damm@opensource.se>");
254MODULE_LICENSE("GPL");
255
256module_init(migor_ts_init);
257module_exit(migor_ts_exit);