linux/drivers/input/touchscreen/cyttsp_core.c
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   1/*
   2 * Core Source for:
   3 * Cypress TrueTouch(TM) Standard Product (TTSP) touchscreen drivers.
   4 * For use with Cypress Txx3xx parts.
   5 * Supported parts include:
   6 * CY8CTST341
   7 * CY8CTMA340
   8 *
   9 * Copyright (C) 2009, 2010, 2011 Cypress Semiconductor, Inc.
  10 * Copyright (C) 2012 Javier Martinez Canillas <javier@dowhile0.org>
  11 *
  12 * This program is free software; you can redistribute it and/or
  13 * modify it under the terms of the GNU General Public License
  14 * version 2, and only version 2, as published by the
  15 * Free Software Foundation.
  16 *
  17 * This program is distributed in the hope that it will be useful,
  18 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  19 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20 * GNU General Public License for more details.
  21 *
  22 * You should have received a copy of the GNU General Public License along
  23 * with this program; if not, write to the Free Software Foundation, Inc.,
  24 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  25 *
  26 * Contact Cypress Semiconductor at www.cypress.com <kev@cypress.com>
  27 *
  28 */
  29
  30#include <linux/delay.h>
  31#include <linux/input.h>
  32#include <linux/input/mt.h>
  33#include <linux/gpio.h>
  34#include <linux/interrupt.h>
  35#include <linux/slab.h>
  36
  37#include "cyttsp_core.h"
  38
  39/* Bootloader number of command keys */
  40#define CY_NUM_BL_KEYS          8
  41
  42/* helpers */
  43#define GET_NUM_TOUCHES(x)              ((x) & 0x0F)
  44#define IS_LARGE_AREA(x)                (((x) & 0x10) >> 4)
  45#define IS_BAD_PKT(x)                   ((x) & 0x20)
  46#define IS_VALID_APP(x)                 ((x) & 0x01)
  47#define IS_OPERATIONAL_ERR(x)           ((x) & 0x3F)
  48#define GET_HSTMODE(reg)                (((reg) & 0x70) >> 4)
  49#define GET_BOOTLOADERMODE(reg)         (((reg) & 0x10) >> 4)
  50
  51#define CY_REG_BASE                     0x00
  52#define CY_REG_ACT_DIST                 0x1E
  53#define CY_REG_ACT_INTRVL               0x1D
  54#define CY_REG_TCH_TMOUT                (CY_REG_ACT_INTRVL + 1)
  55#define CY_REG_LP_INTRVL                (CY_REG_TCH_TMOUT + 1)
  56#define CY_MAXZ                         255
  57#define CY_DELAY_DFLT                   20 /* ms */
  58#define CY_DELAY_MAX                    500
  59#define CY_ACT_DIST_DFLT                0xF8
  60#define CY_HNDSHK_BIT                   0x80
  61/* device mode bits */
  62#define CY_OPERATE_MODE                 0x00
  63#define CY_SYSINFO_MODE                 0x10
  64/* power mode select bits */
  65#define CY_SOFT_RESET_MODE              0x01 /* return to Bootloader mode */
  66#define CY_DEEP_SLEEP_MODE              0x02
  67#define CY_LOW_POWER_MODE               0x04
  68
  69/* Slots management */
  70#define CY_MAX_FINGER                   4
  71#define CY_MAX_ID                       16
  72
  73static const u8 bl_command[] = {
  74        0x00,                   /* file offset */
  75        0xFF,                   /* command */
  76        0xA5,                   /* exit bootloader command */
  77        0, 1, 2, 3, 4, 5, 6, 7  /* default keys */
  78};
  79
  80static int ttsp_read_block_data(struct cyttsp *ts, u8 command,
  81                                u8 length, void *buf)
  82{
  83        int error;
  84        int tries;
  85
  86        for (tries = 0; tries < CY_NUM_RETRY; tries++) {
  87                error = ts->bus_ops->read(ts, command, length, buf);
  88                if (!error)
  89                        return 0;
  90
  91                msleep(CY_DELAY_DFLT);
  92        }
  93
  94        return -EIO;
  95}
  96
  97static int ttsp_write_block_data(struct cyttsp *ts, u8 command,
  98                                 u8 length, void *buf)
  99{
 100        int error;
 101        int tries;
 102
 103        for (tries = 0; tries < CY_NUM_RETRY; tries++) {
 104                error = ts->bus_ops->write(ts, command, length, buf);
 105                if (!error)
 106                        return 0;
 107
 108                msleep(CY_DELAY_DFLT);
 109        }
 110
 111        return -EIO;
 112}
 113
 114static int ttsp_send_command(struct cyttsp *ts, u8 cmd)
 115{
 116        return ttsp_write_block_data(ts, CY_REG_BASE, sizeof(cmd), &cmd);
 117}
 118
 119static int cyttsp_load_bl_regs(struct cyttsp *ts)
 120{
 121        memset(&ts->bl_data, 0, sizeof(ts->bl_data));
 122        ts->bl_data.bl_status = 0x10;
 123
 124        return ttsp_read_block_data(ts, CY_REG_BASE,
 125                                    sizeof(ts->bl_data), &ts->bl_data);
 126}
 127
 128static int cyttsp_exit_bl_mode(struct cyttsp *ts)
 129{
 130        int error;
 131        u8 bl_cmd[sizeof(bl_command)];
 132
 133        memcpy(bl_cmd, bl_command, sizeof(bl_command));
 134        if (ts->pdata->bl_keys)
 135                memcpy(&bl_cmd[sizeof(bl_command) - CY_NUM_BL_KEYS],
 136                        ts->pdata->bl_keys, sizeof(bl_command));
 137
 138        error = ttsp_write_block_data(ts, CY_REG_BASE,
 139                                      sizeof(bl_cmd), bl_cmd);
 140        if (error)
 141                return error;
 142
 143        /* wait for TTSP Device to complete the operation */
 144        msleep(CY_DELAY_DFLT);
 145
 146        error = cyttsp_load_bl_regs(ts);
 147        if (error)
 148                return error;
 149
 150        if (GET_BOOTLOADERMODE(ts->bl_data.bl_status))
 151                return -EIO;
 152
 153        return 0;
 154}
 155
 156static int cyttsp_set_operational_mode(struct cyttsp *ts)
 157{
 158        int error;
 159
 160        error = ttsp_send_command(ts, CY_OPERATE_MODE);
 161        if (error)
 162                return error;
 163
 164        /* wait for TTSP Device to complete switch to Operational mode */
 165        error = ttsp_read_block_data(ts, CY_REG_BASE,
 166                                     sizeof(ts->xy_data), &ts->xy_data);
 167        if (error)
 168                return error;
 169
 170        return ts->xy_data.act_dist == CY_ACT_DIST_DFLT ? -EIO : 0;
 171}
 172
 173static int cyttsp_set_sysinfo_mode(struct cyttsp *ts)
 174{
 175        int error;
 176
 177        memset(&ts->sysinfo_data, 0, sizeof(ts->sysinfo_data));
 178
 179        /* switch to sysinfo mode */
 180        error = ttsp_send_command(ts, CY_SYSINFO_MODE);
 181        if (error)
 182                return error;
 183
 184        /* read sysinfo registers */
 185        msleep(CY_DELAY_DFLT);
 186        error = ttsp_read_block_data(ts, CY_REG_BASE, sizeof(ts->sysinfo_data),
 187                                      &ts->sysinfo_data);
 188        if (error)
 189                return error;
 190
 191        if (!ts->sysinfo_data.tts_verh && !ts->sysinfo_data.tts_verl)
 192                return -EIO;
 193
 194        return 0;
 195}
 196
 197static int cyttsp_set_sysinfo_regs(struct cyttsp *ts)
 198{
 199        int retval = 0;
 200
 201        if (ts->pdata->act_intrvl != CY_ACT_INTRVL_DFLT ||
 202            ts->pdata->tch_tmout != CY_TCH_TMOUT_DFLT ||
 203            ts->pdata->lp_intrvl != CY_LP_INTRVL_DFLT) {
 204
 205                u8 intrvl_ray[] = {
 206                        ts->pdata->act_intrvl,
 207                        ts->pdata->tch_tmout,
 208                        ts->pdata->lp_intrvl
 209                };
 210
 211                /* set intrvl registers */
 212                retval = ttsp_write_block_data(ts, CY_REG_ACT_INTRVL,
 213                                        sizeof(intrvl_ray), intrvl_ray);
 214                msleep(CY_DELAY_DFLT);
 215        }
 216
 217        return retval;
 218}
 219
 220static int cyttsp_soft_reset(struct cyttsp *ts)
 221{
 222        unsigned long timeout;
 223        int retval;
 224
 225        /* wait for interrupt to set ready completion */
 226        INIT_COMPLETION(ts->bl_ready);
 227        ts->state = CY_BL_STATE;
 228
 229        enable_irq(ts->irq);
 230
 231        retval = ttsp_send_command(ts, CY_SOFT_RESET_MODE);
 232        if (retval)
 233                goto out;
 234
 235        timeout = wait_for_completion_timeout(&ts->bl_ready,
 236                        msecs_to_jiffies(CY_DELAY_DFLT * CY_DELAY_MAX));
 237        retval = timeout ? 0 : -EIO;
 238
 239out:
 240        ts->state = CY_IDLE_STATE;
 241        disable_irq(ts->irq);
 242        return retval;
 243}
 244
 245static int cyttsp_act_dist_setup(struct cyttsp *ts)
 246{
 247        u8 act_dist_setup = ts->pdata->act_dist;
 248
 249        /* Init gesture; active distance setup */
 250        return ttsp_write_block_data(ts, CY_REG_ACT_DIST,
 251                                sizeof(act_dist_setup), &act_dist_setup);
 252}
 253
 254static void cyttsp_extract_track_ids(struct cyttsp_xydata *xy_data, int *ids)
 255{
 256        ids[0] = xy_data->touch12_id >> 4;
 257        ids[1] = xy_data->touch12_id & 0xF;
 258        ids[2] = xy_data->touch34_id >> 4;
 259        ids[3] = xy_data->touch34_id & 0xF;
 260}
 261
 262static const struct cyttsp_tch *cyttsp_get_tch(struct cyttsp_xydata *xy_data,
 263                                               int idx)
 264{
 265        switch (idx) {
 266        case 0:
 267                return &xy_data->tch1;
 268        case 1:
 269                return &xy_data->tch2;
 270        case 2:
 271                return &xy_data->tch3;
 272        case 3:
 273                return &xy_data->tch4;
 274        default:
 275                return NULL;
 276        }
 277}
 278
 279static void cyttsp_report_tchdata(struct cyttsp *ts)
 280{
 281        struct cyttsp_xydata *xy_data = &ts->xy_data;
 282        struct input_dev *input = ts->input;
 283        int num_tch = GET_NUM_TOUCHES(xy_data->tt_stat);
 284        const struct cyttsp_tch *tch;
 285        int ids[CY_MAX_ID];
 286        int i;
 287        DECLARE_BITMAP(used, CY_MAX_ID);
 288
 289        if (IS_LARGE_AREA(xy_data->tt_stat) == 1) {
 290                /* terminate all active tracks */
 291                num_tch = 0;
 292                dev_dbg(ts->dev, "%s: Large area detected\n", __func__);
 293        } else if (num_tch > CY_MAX_FINGER) {
 294                /* terminate all active tracks */
 295                num_tch = 0;
 296                dev_dbg(ts->dev, "%s: Num touch error detected\n", __func__);
 297        } else if (IS_BAD_PKT(xy_data->tt_mode)) {
 298                /* terminate all active tracks */
 299                num_tch = 0;
 300                dev_dbg(ts->dev, "%s: Invalid buffer detected\n", __func__);
 301        }
 302
 303        cyttsp_extract_track_ids(xy_data, ids);
 304
 305        bitmap_zero(used, CY_MAX_ID);
 306
 307        for (i = 0; i < num_tch; i++) {
 308                tch = cyttsp_get_tch(xy_data, i);
 309
 310                input_mt_slot(input, ids[i]);
 311                input_mt_report_slot_state(input, MT_TOOL_FINGER, true);
 312                input_report_abs(input, ABS_MT_POSITION_X, be16_to_cpu(tch->x));
 313                input_report_abs(input, ABS_MT_POSITION_Y, be16_to_cpu(tch->y));
 314                input_report_abs(input, ABS_MT_TOUCH_MAJOR, tch->z);
 315
 316                __set_bit(ids[i], used);
 317        }
 318
 319        for (i = 0; i < CY_MAX_ID; i++) {
 320                if (test_bit(i, used))
 321                        continue;
 322
 323                input_mt_slot(input, i);
 324                input_mt_report_slot_state(input, MT_TOOL_FINGER, false);
 325        }
 326
 327        input_sync(input);
 328}
 329
 330static irqreturn_t cyttsp_irq(int irq, void *handle)
 331{
 332        struct cyttsp *ts = handle;
 333        int error;
 334
 335        if (unlikely(ts->state == CY_BL_STATE)) {
 336                complete(&ts->bl_ready);
 337                goto out;
 338        }
 339
 340        /* Get touch data from CYTTSP device */
 341        error = ttsp_read_block_data(ts, CY_REG_BASE,
 342                                 sizeof(struct cyttsp_xydata), &ts->xy_data);
 343        if (error)
 344                goto out;
 345
 346        /* provide flow control handshake */
 347        if (ts->pdata->use_hndshk) {
 348                error = ttsp_send_command(ts,
 349                                ts->xy_data.hst_mode ^ CY_HNDSHK_BIT);
 350                if (error)
 351                        goto out;
 352        }
 353
 354        if (unlikely(ts->state == CY_IDLE_STATE))
 355                goto out;
 356
 357        if (GET_BOOTLOADERMODE(ts->xy_data.tt_mode)) {
 358                /*
 359                 * TTSP device has reset back to bootloader mode.
 360                 * Restore to operational mode.
 361                 */
 362                error = cyttsp_exit_bl_mode(ts);
 363                if (error) {
 364                        dev_err(ts->dev,
 365                                "Could not return to operational mode, err: %d\n",
 366                                error);
 367                        ts->state = CY_IDLE_STATE;
 368                }
 369        } else {
 370                cyttsp_report_tchdata(ts);
 371        }
 372
 373out:
 374        return IRQ_HANDLED;
 375}
 376
 377static int cyttsp_power_on(struct cyttsp *ts)
 378{
 379        int error;
 380
 381        error = cyttsp_soft_reset(ts);
 382        if (error)
 383                return error;
 384
 385        error = cyttsp_load_bl_regs(ts);
 386        if (error)
 387                return error;
 388
 389        if (GET_BOOTLOADERMODE(ts->bl_data.bl_status) &&
 390            IS_VALID_APP(ts->bl_data.bl_status)) {
 391                error = cyttsp_exit_bl_mode(ts);
 392                if (error)
 393                        return error;
 394        }
 395
 396        if (GET_HSTMODE(ts->bl_data.bl_file) != CY_OPERATE_MODE ||
 397            IS_OPERATIONAL_ERR(ts->bl_data.bl_status)) {
 398                return -ENODEV;
 399        }
 400
 401        error = cyttsp_set_sysinfo_mode(ts);
 402        if (error)
 403                return error;
 404
 405        error = cyttsp_set_sysinfo_regs(ts);
 406        if (error)
 407                return error;
 408
 409        error = cyttsp_set_operational_mode(ts);
 410        if (error)
 411                return error;
 412
 413        /* init active distance */
 414        error = cyttsp_act_dist_setup(ts);
 415        if (error)
 416                return error;
 417
 418        ts->state = CY_ACTIVE_STATE;
 419
 420        return 0;
 421}
 422
 423static int cyttsp_enable(struct cyttsp *ts)
 424{
 425        int error;
 426
 427        /*
 428         * The device firmware can wake on an I2C or SPI memory slave
 429         * address match. So just reading a register is sufficient to
 430         * wake up the device. The first read attempt will fail but it
 431         * will wake it up making the second read attempt successful.
 432         */
 433        error = ttsp_read_block_data(ts, CY_REG_BASE,
 434                                     sizeof(ts->xy_data), &ts->xy_data);
 435        if (error)
 436                return error;
 437
 438        if (GET_HSTMODE(ts->xy_data.hst_mode))
 439                return -EIO;
 440
 441        enable_irq(ts->irq);
 442
 443        return 0;
 444}
 445
 446static int cyttsp_disable(struct cyttsp *ts)
 447{
 448        int error;
 449
 450        error = ttsp_send_command(ts, CY_LOW_POWER_MODE);
 451        if (error)
 452                return error;
 453
 454        disable_irq(ts->irq);
 455
 456        return 0;
 457}
 458
 459#ifdef CONFIG_PM_SLEEP
 460static int cyttsp_suspend(struct device *dev)
 461{
 462        struct cyttsp *ts = dev_get_drvdata(dev);
 463        int retval = 0;
 464
 465        mutex_lock(&ts->input->mutex);
 466
 467        if (ts->input->users) {
 468                retval = cyttsp_disable(ts);
 469                if (retval == 0)
 470                        ts->suspended = true;
 471        }
 472
 473        mutex_unlock(&ts->input->mutex);
 474
 475        return retval;
 476}
 477
 478static int cyttsp_resume(struct device *dev)
 479{
 480        struct cyttsp *ts = dev_get_drvdata(dev);
 481
 482        mutex_lock(&ts->input->mutex);
 483
 484        if (ts->input->users)
 485                cyttsp_enable(ts);
 486
 487        ts->suspended = false;
 488
 489        mutex_unlock(&ts->input->mutex);
 490
 491        return 0;
 492}
 493
 494#endif
 495
 496SIMPLE_DEV_PM_OPS(cyttsp_pm_ops, cyttsp_suspend, cyttsp_resume);
 497EXPORT_SYMBOL_GPL(cyttsp_pm_ops);
 498
 499static int cyttsp_open(struct input_dev *dev)
 500{
 501        struct cyttsp *ts = input_get_drvdata(dev);
 502        int retval = 0;
 503
 504        if (!ts->suspended)
 505                retval = cyttsp_enable(ts);
 506
 507        return retval;
 508}
 509
 510static void cyttsp_close(struct input_dev *dev)
 511{
 512        struct cyttsp *ts = input_get_drvdata(dev);
 513
 514        if (!ts->suspended)
 515                cyttsp_disable(ts);
 516}
 517
 518struct cyttsp *cyttsp_probe(const struct cyttsp_bus_ops *bus_ops,
 519                            struct device *dev, int irq, size_t xfer_buf_size)
 520{
 521        const struct cyttsp_platform_data *pdata = dev->platform_data;
 522        struct cyttsp *ts;
 523        struct input_dev *input_dev;
 524        int error;
 525
 526        if (!pdata || !pdata->name || irq <= 0) {
 527                error = -EINVAL;
 528                goto err_out;
 529        }
 530
 531        ts = kzalloc(sizeof(*ts) + xfer_buf_size, GFP_KERNEL);
 532        input_dev = input_allocate_device();
 533        if (!ts || !input_dev) {
 534                error = -ENOMEM;
 535                goto err_free_mem;
 536        }
 537
 538        ts->dev = dev;
 539        ts->input = input_dev;
 540        ts->pdata = dev->platform_data;
 541        ts->bus_ops = bus_ops;
 542        ts->irq = irq;
 543
 544        init_completion(&ts->bl_ready);
 545        snprintf(ts->phys, sizeof(ts->phys), "%s/input0", dev_name(dev));
 546
 547        if (pdata->init) {
 548                error = pdata->init();
 549                if (error) {
 550                        dev_err(ts->dev, "platform init failed, err: %d\n",
 551                                error);
 552                        goto err_free_mem;
 553                }
 554        }
 555
 556        input_dev->name = pdata->name;
 557        input_dev->phys = ts->phys;
 558        input_dev->id.bustype = bus_ops->bustype;
 559        input_dev->dev.parent = ts->dev;
 560
 561        input_dev->open = cyttsp_open;
 562        input_dev->close = cyttsp_close;
 563
 564        input_set_drvdata(input_dev, ts);
 565
 566        __set_bit(EV_ABS, input_dev->evbit);
 567        input_set_abs_params(input_dev, ABS_MT_POSITION_X,
 568                             0, pdata->maxx, 0, 0);
 569        input_set_abs_params(input_dev, ABS_MT_POSITION_Y,
 570                             0, pdata->maxy, 0, 0);
 571        input_set_abs_params(input_dev, ABS_MT_TOUCH_MAJOR,
 572                             0, CY_MAXZ, 0, 0);
 573
 574        input_mt_init_slots(input_dev, CY_MAX_ID, 0);
 575
 576        error = request_threaded_irq(ts->irq, NULL, cyttsp_irq,
 577                                     IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
 578                                     pdata->name, ts);
 579        if (error) {
 580                dev_err(ts->dev, "failed to request IRQ %d, err: %d\n",
 581                        ts->irq, error);
 582                goto err_platform_exit;
 583        }
 584
 585        disable_irq(ts->irq);
 586
 587        error = cyttsp_power_on(ts);
 588        if (error)
 589                goto err_free_irq;
 590
 591        error = input_register_device(input_dev);
 592        if (error) {
 593                dev_err(ts->dev, "failed to register input device: %d\n",
 594                        error);
 595                goto err_free_irq;
 596        }
 597
 598        return ts;
 599
 600err_free_irq:
 601        free_irq(ts->irq, ts);
 602err_platform_exit:
 603        if (pdata->exit)
 604                pdata->exit();
 605err_free_mem:
 606        input_free_device(input_dev);
 607        kfree(ts);
 608err_out:
 609        return ERR_PTR(error);
 610}
 611EXPORT_SYMBOL_GPL(cyttsp_probe);
 612
 613void cyttsp_remove(struct cyttsp *ts)
 614{
 615        free_irq(ts->irq, ts);
 616        input_unregister_device(ts->input);
 617        if (ts->pdata->exit)
 618                ts->pdata->exit();
 619        kfree(ts);
 620}
 621EXPORT_SYMBOL_GPL(cyttsp_remove);
 622
 623MODULE_LICENSE("GPL");
 624MODULE_DESCRIPTION("Cypress TrueTouch(R) Standard touchscreen driver core");
 625MODULE_AUTHOR("Cypress");
 626