drivers/input/touchscreen/st1232.c

   1 /*
   2  * ST1232 Touchscreen Controller Driver
   3  *
   4  * Copyright (C) 2010 Renesas Solutions Corp.
   5  *      Tony SIM <chinyeow.sim.xt@renesas.com>
   6  *
   7  * Using code from:
   8  *  - android.git.kernel.org: projects/kernel/common.git: synaptics_i2c_rmi.c
   9  *      Copyright (C) 2007 Google, Inc.
  10  *
  11  * This software is licensed under the terms of the GNU General Public
  12  * License version 2, as published by the Free Software Foundation, and
  13  * may be copied, distributed, and modified under those terms.
  14  *
  15  * This program is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18  * GNU General Public License for more details.
  19  */
  20
  21 #include <linux/delay.h>
  22 #include <linux/i2c.h>
  23 #include <linux/input.h>
  24 #include <linux/interrupt.h>
  25 #include <linux/module.h>
  26 #include <linux/slab.h>
  27 #include <linux/types.h>
  28
  29 #define ST1232_TS_NAME  "st1232-ts"
  30
  31 #define MIN_X           0x00
  32 #define MIN_Y           0x00
  33 #define MAX_X           0x31f   /* (800 - 1) */
  34 #define MAX_Y           0x1df   /* (480 - 1) */
  35 #define MAX_AREA        0xff
  36 #define MAX_FINGERS     2
  37
  38 struct st1232_ts_finger {
  39         u16 x;
  40         u16 y;
  41         u8 t;
  42         bool is_valid;
  43 };
  44
  45 struct st1232_ts_data {
  46         struct i2c_client *client;
  47         struct input_dev *input_dev;
  48         struct st1232_ts_finger finger[MAX_FINGERS];
  49 };
  50
  51 static int st1232_ts_read_data(struct st1232_ts_data *ts)
  52 {
  53         struct st1232_ts_finger *finger = ts->finger;
  54         struct i2c_client *client = ts->client;
  55         struct i2c_msg msg[2];
  56         int error;
  57         u8 start_reg;
  58         u8 buf[10];
  59
  60         /* read touchscreen data from ST1232 */
  61         msg[0].addr = client->addr;
  62         msg[0].flags = 0;
  63         msg[0].len = 1;
  64         msg[0].buf = &start_reg;
  65         start_reg = 0x10;
  66
  67         msg[1].addr = ts->client->addr;
  68         msg[1].flags = I2C_M_RD;
  69         msg[1].len = sizeof(buf);
  70         msg[1].buf = buf;
  71
  72         error = i2c_transfer(client->adapter, msg, 2);
  73         if (error < 0)
  74                 return error;
  75
  76         /* get "valid" bits */
  77         finger[0].is_valid = buf[2] >> 7;
  78         finger[1].is_valid = buf[5] >> 7;
  79
  80         /* get xy coordinate */
  81         if (finger[0].is_valid) {
  82                 finger[0].x = ((buf[2] & 0x0070) << 4) | buf[3];
  83                 finger[0].y = ((buf[2] & 0x0007) << 8) | buf[4];
  84                 finger[0].t = buf[8];
  85         }
  86
  87         if (finger[1].is_valid) {
  88                 finger[1].x = ((buf[5] & 0x0070) << 4) | buf[6];
  89                 finger[1].y = ((buf[5] & 0x0007) << 8) | buf[7];
  90                 finger[1].t = buf[9];
  91         }
  92
  93         return 0;
  94 }
  95
  96 static irqreturn_t st1232_ts_irq_handler(int irq, void *dev_id)
  97 {
  98         struct st1232_ts_data *ts = dev_id;
  99         struct st1232_ts_finger *finger = ts->finger;
 100         struct input_dev *input_dev = ts->input_dev;
 101         int count = 0;
 102         int i, ret;
 103
 104         ret = st1232_ts_read_data(ts);
 105         if (ret < 0)
 106                 goto end;
 107
 108         /* multi touch protocol */
 109         for (i = 0; i < MAX_FINGERS; i++) {
 110                 if (!finger[i].is_valid)
 111                         continue;
 112
 113                 input_report_abs(input_dev, ABS_MT_TOUCH_MAJOR, finger[i].t);
 114                 input_report_abs(input_dev, ABS_MT_POSITION_X, finger[i].x);
 115                 input_report_abs(input_dev, ABS_MT_POSITION_Y, finger[i].y);
 116                 input_mt_sync(input_dev);
 117                 count++;
 118         }
 119
 120         /* SYN_MT_REPORT only if no contact */
 121         if (!count)
 122                 input_mt_sync(input_dev);
 123
 124         /* SYN_REPORT */
 125         input_sync(input_dev);
 126
 127 end:
 128         return IRQ_HANDLED;
 129 }
 130
 131 static int __devinit st1232_ts_probe(struct i2c_client *client,
 132                                         const struct i2c_device_id *id)
 133 {
 134         struct st1232_ts_data *ts;
 135         struct input_dev *input_dev;
 136         int error;
 137
 138         if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
 139                 dev_err(&client->dev, "need I2C_FUNC_I2C\n");
 140                 return -EIO;
 141         }
 142
 143         if (!client->irq) {
 144                 dev_err(&client->dev, "no IRQ?\n");
 145                 return -EINVAL;
 146         }
 147
 148
 149         ts = kzalloc(sizeof(struct st1232_ts_data), GFP_KERNEL);
 150         input_dev = input_allocate_device();
 151         if (!ts || !input_dev) {
 152                 error = -ENOMEM;
 153                 goto err_free_mem;
 154         }
 155
 156         ts->client = client;
 157         ts->input_dev = input_dev;
 158
 159         input_dev->name = "st1232-touchscreen";
 160         input_dev->id.bustype = BUS_I2C;
 161         input_dev->dev.parent = &client->dev;
 162
 163         __set_bit(EV_SYN, input_dev->evbit);
 164         __set_bit(EV_KEY, input_dev->evbit);
 165         __set_bit(EV_ABS, input_dev->evbit);
 166
 167         input_set_abs_params(input_dev, ABS_MT_TOUCH_MAJOR, 0, MAX_AREA, 0, 0);
 168         input_set_abs_params(input_dev, ABS_MT_POSITION_X, MIN_X, MAX_X, 0, 0);
 169         input_set_abs_params(input_dev, ABS_MT_POSITION_Y, MIN_Y, MAX_Y, 0, 0);
 170
 171         error = request_threaded_irq(client->irq, NULL, st1232_ts_irq_handler,
 172                                      IRQF_ONESHOT, client->name, ts);
 173         if (error) {
 174                 dev_err(&client->dev, "Failed to register interrupt\n");
 175                 goto err_free_mem;
 176         }
 177
 178         error = input_register_device(ts->input_dev);
 179         if (error) {
 180                 dev_err(&client->dev, "Unable to register %s input device\n",
 181                         input_dev->name);
 182                 goto err_free_irq;
 183         }
 184
 185         i2c_set_clientdata(client, ts);
 186         device_init_wakeup(&client->dev, 1);
 187
 188         return 0;
 189
 190 err_free_irq:
 191         free_irq(client->irq, ts);
 192 err_free_mem:
 193         input_free_device(input_dev);
 194         kfree(ts);
 195         return error;
 196 }
 197
 198 static int __devexit st1232_ts_remove(struct i2c_client *client)
 199 {
 200         struct st1232_ts_data *ts = i2c_get_clientdata(client);
 201
 202         device_init_wakeup(&client->dev, 0);
 203         free_irq(client->irq, ts);
 204         input_unregister_device(ts->input_dev);
 205         kfree(ts);
 206
 207         return 0;
 208 }
 209
 210 #ifdef CONFIG_PM
 211 static int st1232_ts_suspend(struct device *dev)
 212 {
 213         struct i2c_client *client = to_i2c_client(dev);
 214
 215         if (device_may_wakeup(&client->dev))
 216                 enable_irq_wake(client->irq);
 217         else
 218                 disable_irq(client->irq);
 219
 220         return 0;
 221 }
 222
 223 static int st1232_ts_resume(struct device *dev)
 224 {
 225         struct i2c_client *client = to_i2c_client(dev);
 226
 227         if (device_may_wakeup(&client->dev))
 228                 disable_irq_wake(client->irq);
 229         else
 230                 enable_irq(client->irq);
 231
 232         return 0;
 233 }
 234
 235 static const struct dev_pm_ops st1232_ts_pm_ops = {
 236         .suspend        = st1232_ts_suspend,
 237         .resume         = st1232_ts_resume,
 238 };
 239 #endif
 240
 241 static const struct i2c_device_id st1232_ts_id[] = {
 242         { ST1232_TS_NAME, 0 },
 243         { }
 244 };
 245 MODULE_DEVICE_TABLE(i2c, st1232_ts_id);
 246
 247 static struct i2c_driver st1232_ts_driver = {
 248         .probe          = st1232_ts_probe,
 249         .remove         = __devexit_p(st1232_ts_remove),
 250         .id_table       = st1232_ts_id,
 251         .driver = {
 252                 .name   = ST1232_TS_NAME,
 253                 .owner  = THIS_MODULE,
 254 #ifdef CONFIG_PM
 255                 .pm     = &st1232_ts_pm_ops,
 256 #endif
 257         },
 258 };
 259
 260 static int __init st1232_ts_init(void)
 261 {
 262         return i2c_add_driver(&st1232_ts_driver);
 263 }
 264 module_init(st1232_ts_init);
 265
 266 static void __exit st1232_ts_exit(void)
 267 {
 268         i2c_del_driver(&st1232_ts_driver);
 269 }
 270 module_exit(st1232_ts_exit);
 271
 272 MODULE_AUTHOR("Tony SIM <chinyeow.sim.xt@renesas.com>");
 273 MODULE_DESCRIPTION("SITRONIX ST1232 Touchscreen Controller Driver");
 274 MODULE_LICENSE("GPL");