linux/drivers/input/touchscreen/cy8ctmg110_ts.c
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   1/*
   2 * Driver for cypress touch screen controller
   3 *
   4 * Copyright (c) 2009 Aava Mobile
   5 *
   6 * Some cleanups by Alan Cox <alan@linux.intel.com>
   7 *
   8 * This program is free software; you can redistribute it and/or modify
   9 * it under the terms of the GNU General Public License version 2 as
  10 * published by the Free Software Foundation.
  11 *
  12 * This program is distributed in the hope that it will be useful,
  13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 * GNU General Public License for more details.
  16 *
  17 * You should have received a copy of the GNU General Public License
  18 * along with this program; if not, write to the Free Software
  19 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  20 */
  21
  22#include <linux/module.h>
  23#include <linux/kernel.h>
  24#include <linux/input.h>
  25#include <linux/slab.h>
  26#include <linux/interrupt.h>
  27#include <linux/io.h>
  28#include <linux/i2c.h>
  29#include <linux/gpio.h>
  30#include <linux/input/cy8ctmg110_pdata.h>
  31
  32#define CY8CTMG110_DRIVER_NAME      "cy8ctmg110"
  33
  34/* Touch coordinates */
  35#define CY8CTMG110_X_MIN                0
  36#define CY8CTMG110_Y_MIN                0
  37#define CY8CTMG110_X_MAX                759
  38#define CY8CTMG110_Y_MAX                465
  39
  40
  41/* cy8ctmg110 register definitions */
  42#define CY8CTMG110_TOUCH_WAKEUP_TIME    0
  43#define CY8CTMG110_TOUCH_SLEEP_TIME     2
  44#define CY8CTMG110_TOUCH_X1             3
  45#define CY8CTMG110_TOUCH_Y1             5
  46#define CY8CTMG110_TOUCH_X2             7
  47#define CY8CTMG110_TOUCH_Y2             9
  48#define CY8CTMG110_FINGERS              11
  49#define CY8CTMG110_GESTURE              12
  50#define CY8CTMG110_REG_MAX              13
  51
  52
  53/*
  54 * The touch driver structure.
  55 */
  56struct cy8ctmg110 {
  57        struct input_dev *input;
  58        char phys[32];
  59        struct i2c_client *client;
  60        int reset_pin;
  61        int irq_pin;
  62};
  63
  64/*
  65 * cy8ctmg110_power is the routine that is called when touch hardware
  66 * will powered off or on.
  67 */
  68static void cy8ctmg110_power(struct cy8ctmg110 *ts, bool poweron)
  69{
  70        if (ts->reset_pin)
  71                gpio_direction_output(ts->reset_pin, 1 - poweron);
  72}
  73
  74static int cy8ctmg110_write_regs(struct cy8ctmg110 *tsc, unsigned char reg,
  75                unsigned char len, unsigned char *value)
  76{
  77        struct i2c_client *client = tsc->client;
  78        int ret;
  79        unsigned char i2c_data[6];
  80
  81        BUG_ON(len > 5);
  82
  83        i2c_data[0] = reg;
  84        memcpy(i2c_data + 1, value, len);
  85
  86        ret = i2c_master_send(client, i2c_data, len + 1);
  87        if (ret != len + 1) {
  88                dev_err(&client->dev, "i2c write data cmd failed\n");
  89                return ret < 0 ? ret : -EIO;
  90        }
  91
  92        return 0;
  93}
  94
  95static int cy8ctmg110_read_regs(struct cy8ctmg110 *tsc,
  96                unsigned char *data, unsigned char len, unsigned char cmd)
  97{
  98        struct i2c_client *client = tsc->client;
  99        int ret;
 100        struct i2c_msg msg[2] = {
 101                /* first write slave position to i2c devices */
 102                {
 103                        .addr = client->addr,
 104                        .len = 1,
 105                        .buf = &cmd
 106                },
 107                /* Second read data from position */
 108                {
 109                        .addr = client->addr,
 110                        .flags = I2C_M_RD,
 111                        .len = len,
 112                        .buf = data
 113                }
 114        };
 115
 116        ret = i2c_transfer(client->adapter, msg, 2);
 117        if (ret < 0)
 118                return ret;
 119
 120        return 0;
 121}
 122
 123static int cy8ctmg110_touch_pos(struct cy8ctmg110 *tsc)
 124{
 125        struct input_dev *input = tsc->input;
 126        unsigned char reg_p[CY8CTMG110_REG_MAX];
 127        int x, y;
 128
 129        memset(reg_p, 0, CY8CTMG110_REG_MAX);
 130
 131        /* Reading coordinates */
 132        if (cy8ctmg110_read_regs(tsc, reg_p, 9, CY8CTMG110_TOUCH_X1) != 0)
 133                return -EIO;
 134
 135        y = reg_p[2] << 8 | reg_p[3];
 136        x = reg_p[0] << 8 | reg_p[1];
 137
 138        /* Number of touch */
 139        if (reg_p[8] == 0) {
 140                input_report_key(input, BTN_TOUCH, 0);
 141        } else  {
 142                input_report_key(input, BTN_TOUCH, 1);
 143                input_report_abs(input, ABS_X, x);
 144                input_report_abs(input, ABS_Y, y);
 145        }
 146
 147        input_sync(input);
 148
 149        return 0;
 150}
 151
 152static int cy8ctmg110_set_sleepmode(struct cy8ctmg110 *ts, bool sleep)
 153{
 154        unsigned char reg_p[3];
 155
 156        if (sleep) {
 157                reg_p[0] = 0x00;
 158                reg_p[1] = 0xff;
 159                reg_p[2] = 5;
 160        } else {
 161                reg_p[0] = 0x10;
 162                reg_p[1] = 0xff;
 163                reg_p[2] = 0;
 164        }
 165
 166        return cy8ctmg110_write_regs(ts, CY8CTMG110_TOUCH_WAKEUP_TIME, 3, reg_p);
 167}
 168
 169static irqreturn_t cy8ctmg110_irq_thread(int irq, void *dev_id)
 170{
 171        struct cy8ctmg110 *tsc = dev_id;
 172
 173        cy8ctmg110_touch_pos(tsc);
 174
 175        return IRQ_HANDLED;
 176}
 177
 178static int cy8ctmg110_probe(struct i2c_client *client,
 179                                        const struct i2c_device_id *id)
 180{
 181        const struct cy8ctmg110_pdata *pdata = dev_get_platdata(&client->dev);
 182        struct cy8ctmg110 *ts;
 183        struct input_dev *input_dev;
 184        int err;
 185
 186        /* No pdata no way forward */
 187        if (pdata == NULL) {
 188                dev_err(&client->dev, "no pdata\n");
 189                return -ENODEV;
 190        }
 191
 192        if (!i2c_check_functionality(client->adapter,
 193                                        I2C_FUNC_SMBUS_READ_WORD_DATA))
 194                return -EIO;
 195
 196        ts = kzalloc(sizeof(struct cy8ctmg110), GFP_KERNEL);
 197        input_dev = input_allocate_device();
 198        if (!ts || !input_dev) {
 199                err = -ENOMEM;
 200                goto err_free_mem;
 201        }
 202
 203        ts->client = client;
 204        ts->input = input_dev;
 205        ts->reset_pin = pdata->reset_pin;
 206        ts->irq_pin = pdata->irq_pin;
 207
 208        snprintf(ts->phys, sizeof(ts->phys),
 209                 "%s/input0", dev_name(&client->dev));
 210
 211        input_dev->name = CY8CTMG110_DRIVER_NAME " Touchscreen";
 212        input_dev->phys = ts->phys;
 213        input_dev->id.bustype = BUS_I2C;
 214        input_dev->dev.parent = &client->dev;
 215
 216        input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
 217        input_dev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH);
 218
 219        input_set_abs_params(input_dev, ABS_X,
 220                        CY8CTMG110_X_MIN, CY8CTMG110_X_MAX, 4, 0);
 221        input_set_abs_params(input_dev, ABS_Y,
 222                        CY8CTMG110_Y_MIN, CY8CTMG110_Y_MAX, 4, 0);
 223
 224        if (ts->reset_pin) {
 225                err = gpio_request(ts->reset_pin, NULL);
 226                if (err) {
 227                        dev_err(&client->dev,
 228                                "Unable to request GPIO pin %d.\n",
 229                                ts->reset_pin);
 230                        goto err_free_mem;
 231                }
 232        }
 233
 234        cy8ctmg110_power(ts, true);
 235        cy8ctmg110_set_sleepmode(ts, false);
 236
 237        err = gpio_request(ts->irq_pin, "touch_irq_key");
 238        if (err < 0) {
 239                dev_err(&client->dev,
 240                        "Failed to request GPIO %d, error %d\n",
 241                        ts->irq_pin, err);
 242                goto err_shutoff_device;
 243        }
 244
 245        err = gpio_direction_input(ts->irq_pin);
 246        if (err < 0) {
 247                dev_err(&client->dev,
 248                        "Failed to configure input direction for GPIO %d, error %d\n",
 249                        ts->irq_pin, err);
 250                goto err_free_irq_gpio;
 251        }
 252
 253        client->irq = gpio_to_irq(ts->irq_pin);
 254        if (client->irq < 0) {
 255                err = client->irq;
 256                dev_err(&client->dev,
 257                        "Unable to get irq number for GPIO %d, error %d\n",
 258                        ts->irq_pin, err);
 259                goto err_free_irq_gpio;
 260        }
 261
 262        err = request_threaded_irq(client->irq, NULL, cy8ctmg110_irq_thread,
 263                                   IRQF_TRIGGER_RISING | IRQF_ONESHOT,
 264                                   "touch_reset_key", ts);
 265        if (err < 0) {
 266                dev_err(&client->dev,
 267                        "irq %d busy? error %d\n", client->irq, err);
 268                goto err_free_irq_gpio;
 269        }
 270
 271        err = input_register_device(input_dev);
 272        if (err)
 273                goto err_free_irq;
 274
 275        i2c_set_clientdata(client, ts);
 276        device_init_wakeup(&client->dev, 1);
 277        return 0;
 278
 279err_free_irq:
 280        free_irq(client->irq, ts);
 281err_free_irq_gpio:
 282        gpio_free(ts->irq_pin);
 283err_shutoff_device:
 284        cy8ctmg110_set_sleepmode(ts, true);
 285        cy8ctmg110_power(ts, false);
 286        if (ts->reset_pin)
 287                gpio_free(ts->reset_pin);
 288err_free_mem:
 289        input_free_device(input_dev);
 290        kfree(ts);
 291        return err;
 292}
 293
 294static int __maybe_unused cy8ctmg110_suspend(struct device *dev)
 295{
 296        struct i2c_client *client = to_i2c_client(dev);
 297        struct cy8ctmg110 *ts = i2c_get_clientdata(client);
 298
 299        if (device_may_wakeup(&client->dev))
 300                enable_irq_wake(client->irq);
 301        else {
 302                cy8ctmg110_set_sleepmode(ts, true);
 303                cy8ctmg110_power(ts, false);
 304        }
 305        return 0;
 306}
 307
 308static int __maybe_unused cy8ctmg110_resume(struct device *dev)
 309{
 310        struct i2c_client *client = to_i2c_client(dev);
 311        struct cy8ctmg110 *ts = i2c_get_clientdata(client);
 312
 313        if (device_may_wakeup(&client->dev))
 314                disable_irq_wake(client->irq);
 315        else {
 316                cy8ctmg110_power(ts, true);
 317                cy8ctmg110_set_sleepmode(ts, false);
 318        }
 319        return 0;
 320}
 321
 322static SIMPLE_DEV_PM_OPS(cy8ctmg110_pm, cy8ctmg110_suspend, cy8ctmg110_resume);
 323
 324static int cy8ctmg110_remove(struct i2c_client *client)
 325{
 326        struct cy8ctmg110 *ts = i2c_get_clientdata(client);
 327
 328        cy8ctmg110_set_sleepmode(ts, true);
 329        cy8ctmg110_power(ts, false);
 330
 331        free_irq(client->irq, ts);
 332        input_unregister_device(ts->input);
 333        gpio_free(ts->irq_pin);
 334        if (ts->reset_pin)
 335                gpio_free(ts->reset_pin);
 336        kfree(ts);
 337
 338        return 0;
 339}
 340
 341static const struct i2c_device_id cy8ctmg110_idtable[] = {
 342        { CY8CTMG110_DRIVER_NAME, 1 },
 343        { }
 344};
 345
 346MODULE_DEVICE_TABLE(i2c, cy8ctmg110_idtable);
 347
 348static struct i2c_driver cy8ctmg110_driver = {
 349        .driver         = {
 350                .owner  = THIS_MODULE,
 351                .name   = CY8CTMG110_DRIVER_NAME,
 352                .pm     = &cy8ctmg110_pm,
 353        },
 354        .id_table       = cy8ctmg110_idtable,
 355        .probe          = cy8ctmg110_probe,
 356        .remove         = cy8ctmg110_remove,
 357};
 358
 359module_i2c_driver(cy8ctmg110_driver);
 360
 361MODULE_AUTHOR("Samuli Konttila <samuli.konttila@aavamobile.com>");
 362MODULE_DESCRIPTION("cy8ctmg110 TouchScreen Driver");
 363MODULE_LICENSE("GPL v2");
 364