drivers/input/misc/kxtj9.c

   1 /*
   2  * Copyright (C) 2011 Kionix, Inc.
   3  * Written by Chris Hudson <chudson@kionix.com>
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License version 2 as
   7  * published by the Free Software Foundation.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program; if not, write to the Free Software
  16  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  17  * 02111-1307, USA
  18  */
  19
  20 #include <linux/delay.h>
  21 #include <linux/i2c.h>
  22 #include <linux/input.h>
  23 #include <linux/interrupt.h>
  24 #include <linux/module.h>
  25 #include <linux/slab.h>
  26 #include <linux/input/kxtj9.h>
  27 #include <linux/input-polldev.h>
  28
  29 #define NAME                    "kxtj9"
  30 #define G_MAX                   8000
  31 /* OUTPUT REGISTERS */
  32 #define XOUT_L                  0x06
  33 #define WHO_AM_I                0x0F
  34 /* CONTROL REGISTERS */
  35 #define INT_REL                 0x1A
  36 #define CTRL_REG1               0x1B
  37 #define INT_CTRL1               0x1E
  38 #define DATA_CTRL               0x21
  39 /* CONTROL REGISTER 1 BITS */
  40 #define PC1_OFF                 0x7F
  41 #define PC1_ON                  (1 << 7)
  42 /* Data ready funtion enable bit: set during probe if using irq mode */
  43 #define DRDYE                   (1 << 5)
  44 /* INTERRUPT CONTROL REGISTER 1 BITS */
  45 /* Set these during probe if using irq mode */
  46 #define KXTJ9_IEL               (1 << 3)
  47 #define KXTJ9_IEA               (1 << 4)
  48 #define KXTJ9_IEN               (1 << 5)
  49 /* INPUT_ABS CONSTANTS */
  50 #define FUZZ                    3
  51 #define FLAT                    3
  52 /* RESUME STATE INDICES */
  53 #define RES_DATA_CTRL           0
  54 #define RES_CTRL_REG1           1
  55 #define RES_INT_CTRL1           2
  56 #define RESUME_ENTRIES          3
  57
  58 /*
  59  * The following table lists the maximum appropriate poll interval for each
  60  * available output data rate.
  61  */
  62 static const struct {
  63         unsigned int cutoff;
  64         u8 mask;
  65 } kxtj9_odr_table[] = {
  66         { 3,    ODR800F },
  67         { 5,    ODR400F },
  68         { 10,   ODR200F },
  69         { 20,   ODR100F },
  70         { 40,   ODR50F  },
  71         { 80,   ODR25F  },
  72         { 0,    ODR12_5F},
  73 };
  74
  75 struct kxtj9_data {
  76         struct i2c_client *client;
  77         struct kxtj9_platform_data pdata;
  78         struct input_dev *input_dev;
  79 #ifdef CONFIG_INPUT_KXTJ9_POLLED_MODE
  80         struct input_polled_dev *poll_dev;
  81 #endif
  82         unsigned int last_poll_interval;
  83         u8 shift;
  84         u8 ctrl_reg1;
  85         u8 data_ctrl;
  86         u8 int_ctrl;
  87 };
  88
  89 static int kxtj9_i2c_read(struct kxtj9_data *tj9, u8 addr, u8 *data, int len)
  90 {
  91         struct i2c_msg msgs[] = {
  92                 {
  93                         .addr = tj9->client->addr,
  94                         .flags = tj9->client->flags,
  95                         .len = 1,
  96                         .buf = &addr,
  97                 },
  98                 {
  99                         .addr = tj9->client->addr,
 100                         .flags = tj9->client->flags | I2C_M_RD,
 101                         .len = len,
 102                         .buf = data,
 103                 },
 104         };
 105
 106         return i2c_transfer(tj9->client->adapter, msgs, 2);
 107 }
 108
 109 static void kxtj9_report_acceleration_data(struct kxtj9_data *tj9)
 110 {
 111         s16 acc_data[3]; /* Data bytes from hardware xL, xH, yL, yH, zL, zH */
 112         s16 x, y, z;
 113         int err;
 114
 115         err = kxtj9_i2c_read(tj9, XOUT_L, (u8 *)acc_data, 6);
 116         if (err < 0)
 117                 dev_err(&tj9->client->dev, "accelerometer data read failed\n");
 118
 119         x = le16_to_cpu(acc_data[tj9->pdata.axis_map_x]) >> tj9->shift;
 120         y = le16_to_cpu(acc_data[tj9->pdata.axis_map_y]) >> tj9->shift;
 121         z = le16_to_cpu(acc_data[tj9->pdata.axis_map_z]) >> tj9->shift;
 122
 123         input_report_abs(tj9->input_dev, ABS_X, tj9->pdata.negate_x ? -x : x);
 124         input_report_abs(tj9->input_dev, ABS_Y, tj9->pdata.negate_y ? -y : y);
 125         input_report_abs(tj9->input_dev, ABS_Z, tj9->pdata.negate_z ? -z : z);
 126         input_sync(tj9->input_dev);
 127 }
 128
 129 static irqreturn_t kxtj9_isr(int irq, void *dev)
 130 {
 131         struct kxtj9_data *tj9 = dev;
 132         int err;
 133
 134         /* data ready is the only possible interrupt type */
 135         kxtj9_report_acceleration_data(tj9);
 136
 137         err = i2c_smbus_read_byte_data(tj9->client, INT_REL);
 138         if (err < 0)
 139                 dev_err(&tj9->client->dev,
 140                         "error clearing interrupt status: %d\n", err);
 141
 142         return IRQ_HANDLED;
 143 }
 144
 145 static int kxtj9_update_g_range(struct kxtj9_data *tj9, u8 new_g_range)
 146 {
 147         switch (new_g_range) {
 148         case KXTJ9_G_2G:
 149                 tj9->shift = 4;
 150                 break;
 151         case KXTJ9_G_4G:
 152                 tj9->shift = 3;
 153                 break;
 154         case KXTJ9_G_8G:
 155                 tj9->shift = 2;
 156                 break;
 157         default:
 158                 return -EINVAL;
 159         }
 160
 161         tj9->ctrl_reg1 &= 0xe7;
 162         tj9->ctrl_reg1 |= new_g_range;
 163
 164         return 0;
 165 }
 166
 167 static int kxtj9_update_odr(struct kxtj9_data *tj9, unsigned int poll_interval)
 168 {
 169         int err;
 170         int i;
 171
 172         /* Use the lowest ODR that can support the requested poll interval */
 173         for (i = 0; i < ARRAY_SIZE(kxtj9_odr_table); i++) {
 174                 tj9->data_ctrl = kxtj9_odr_table[i].mask;
 175                 if (poll_interval < kxtj9_odr_table[i].cutoff)
 176                         break;
 177         }
 178
 179         err = i2c_smbus_write_byte_data(tj9->client, CTRL_REG1, 0);
 180         if (err < 0)
 181                 return err;
 182
 183         err = i2c_smbus_write_byte_data(tj9->client, DATA_CTRL, tj9->data_ctrl);
 184         if (err < 0)
 185                 return err;
 186
 187         err = i2c_smbus_write_byte_data(tj9->client, CTRL_REG1, tj9->ctrl_reg1);
 188         if (err < 0)
 189                 return err;
 190
 191         return 0;
 192 }
 193
 194 static int kxtj9_device_power_on(struct kxtj9_data *tj9)
 195 {
 196         if (tj9->pdata.power_on)
 197                 return tj9->pdata.power_on();
 198
 199         return 0;
 200 }
 201
 202 static void kxtj9_device_power_off(struct kxtj9_data *tj9)
 203 {
 204         int err;
 205
 206         tj9->ctrl_reg1 &= PC1_OFF;
 207         err = i2c_smbus_write_byte_data(tj9->client, CTRL_REG1, tj9->ctrl_reg1);
 208         if (err < 0)
 209                 dev_err(&tj9->client->dev, "soft power off failed\n");
 210
 211         if (tj9->pdata.power_off)
 212                 tj9->pdata.power_off();
 213 }
 214
 215 static int kxtj9_enable(struct kxtj9_data *tj9)
 216 {
 217         int err;
 218
 219         err = kxtj9_device_power_on(tj9);
 220         if (err < 0)
 221                 return err;
 222
 223         /* ensure that PC1 is cleared before updating control registers */
 224         err = i2c_smbus_write_byte_data(tj9->client, CTRL_REG1, 0);
 225         if (err < 0)
 226                 return err;
 227
 228         /* only write INT_CTRL_REG1 if in irq mode */
 229         if (tj9->client->irq) {
 230                 err = i2c_smbus_write_byte_data(tj9->client,
 231                                                 INT_CTRL1, tj9->int_ctrl);
 232                 if (err < 0)
 233                         return err;
 234         }
 235
 236         err = kxtj9_update_g_range(tj9, tj9->pdata.g_range);
 237         if (err < 0)
 238                 return err;
 239
 240         /* turn on outputs */
 241         tj9->ctrl_reg1 |= PC1_ON;
 242         err = i2c_smbus_write_byte_data(tj9->client, CTRL_REG1, tj9->ctrl_reg1);
 243         if (err < 0)
 244                 return err;
 245
 246         err = kxtj9_update_odr(tj9, tj9->last_poll_interval);
 247         if (err < 0)
 248                 return err;
 249
 250         /* clear initial interrupt if in irq mode */
 251         if (tj9->client->irq) {
 252                 err = i2c_smbus_read_byte_data(tj9->client, INT_REL);
 253                 if (err < 0) {
 254                         dev_err(&tj9->client->dev,
 255                                 "error clearing interrupt: %d\n", err);
 256                         goto fail;
 257                 }
 258         }
 259
 260         return 0;
 261
 262 fail:
 263         kxtj9_device_power_off(tj9);
 264         return err;
 265 }
 266
 267 static void kxtj9_disable(struct kxtj9_data *tj9)
 268 {
 269         kxtj9_device_power_off(tj9);
 270 }
 271
 272 static int kxtj9_input_open(struct input_dev *input)
 273 {
 274         struct kxtj9_data *tj9 = input_get_drvdata(input);
 275
 276         return kxtj9_enable(tj9);
 277 }
 278
 279 static void kxtj9_input_close(struct input_dev *dev)
 280 {
 281         struct kxtj9_data *tj9 = input_get_drvdata(dev);
 282
 283         kxtj9_disable(tj9);
 284 }
 285
 286 static void __devinit kxtj9_init_input_device(struct kxtj9_data *tj9,
 287                                               struct input_dev *input_dev)
 288 {
 289         __set_bit(EV_ABS, input_dev->evbit);
 290         input_set_abs_params(input_dev, ABS_X, -G_MAX, G_MAX, FUZZ, FLAT);
 291         input_set_abs_params(input_dev, ABS_Y, -G_MAX, G_MAX, FUZZ, FLAT);
 292         input_set_abs_params(input_dev, ABS_Z, -G_MAX, G_MAX, FUZZ, FLAT);
 293
 294         input_dev->name = "kxtj9_accel";
 295         input_dev->id.bustype = BUS_I2C;
 296         input_dev->dev.parent = &tj9->client->dev;
 297 }
 298
 299 static int __devinit kxtj9_setup_input_device(struct kxtj9_data *tj9)
 300 {
 301         struct input_dev *input_dev;
 302         int err;
 303
 304         input_dev = input_allocate_device();
 305         if (!input_dev) {
 306                 dev_err(&tj9->client->dev, "input device allocate failed\n");
 307                 return -ENOMEM;
 308         }
 309
 310         tj9->input_dev = input_dev;
 311
 312         input_dev->open = kxtj9_input_open;
 313         input_dev->close = kxtj9_input_close;
 314         input_set_drvdata(input_dev, tj9);
 315
 316         kxtj9_init_input_device(tj9, input_dev);
 317
 318         err = input_register_device(tj9->input_dev);
 319         if (err) {
 320                 dev_err(&tj9->client->dev,
 321                         "unable to register input polled device %s: %d\n",
 322                         tj9->input_dev->name, err);
 323                 input_free_device(tj9->input_dev);
 324                 return err;
 325         }
 326
 327         return 0;
 328 }
 329
 330 /*
 331  * When IRQ mode is selected, we need to provide an interface to allow the user
 332  * to change the output data rate of the part.  For consistency, we are using
 333  * the set_poll method, which accepts a poll interval in milliseconds, and then
 334  * calls update_odr() while passing this value as an argument.  In IRQ mode, the
 335  * data outputs will not be read AT the requested poll interval, rather, the
 336  * lowest ODR that can support the requested interval.  The client application
 337  * will be responsible for retrieving data from the input node at the desired
 338  * interval.
 339  */
 340
 341 /* Returns currently selected poll interval (in ms) */
 342 static ssize_t kxtj9_get_poll(struct device *dev,
 343                                 struct device_attribute *attr, char *buf)
 344 {
 345         struct i2c_client *client = to_i2c_client(dev);
 346         struct kxtj9_data *tj9 = i2c_get_clientdata(client);
 347
 348         return sprintf(buf, "%d\n", tj9->last_poll_interval);
 349 }
 350
 351 /* Allow users to select a new poll interval (in ms) */
 352 static ssize_t kxtj9_set_poll(struct device *dev, struct device_attribute *attr,
 353                                                 const char *buf, size_t count)
 354 {
 355         struct i2c_client *client = to_i2c_client(dev);
 356         struct kxtj9_data *tj9 = i2c_get_clientdata(client);
 357         struct input_dev *input_dev = tj9->input_dev;
 358         unsigned int interval;
 359         int error;
 360
 361         error = kstrtouint(buf, 10, &interval);
 362         if (error < 0)
 363                 return error;
 364
 365         /* Lock the device to prevent races with open/close (and itself) */
 366         mutex_lock(&input_dev->mutex);
 367
 368         disable_irq(client->irq);
 369
 370         /*
 371          * Set current interval to the greater of the minimum interval or
 372          * the requested interval
 373          */
 374         tj9->last_poll_interval = max(interval, tj9->pdata.min_interval);
 375
 376         kxtj9_update_odr(tj9, tj9->last_poll_interval);
 377
 378         enable_irq(client->irq);
 379         mutex_unlock(&input_dev->mutex);
 380
 381         return count;
 382 }
 383
 384 static DEVICE_ATTR(poll, S_IRUGO|S_IWUSR, kxtj9_get_poll, kxtj9_set_poll);
 385
 386 static struct attribute *kxtj9_attributes[] = {
 387         &dev_attr_poll.attr,
 388         NULL
 389 };
 390
 391 static struct attribute_group kxtj9_attribute_group = {
 392         .attrs = kxtj9_attributes
 393 };
 394
 395
 396 #ifdef CONFIG_INPUT_KXTJ9_POLLED_MODE
 397 static void kxtj9_poll(struct input_polled_dev *dev)
 398 {
 399         struct kxtj9_data *tj9 = dev->private;
 400         unsigned int poll_interval = dev->poll_interval;
 401
 402         kxtj9_report_acceleration_data(tj9);
 403
 404         if (poll_interval != tj9->last_poll_interval) {
 405                 kxtj9_update_odr(tj9, poll_interval);
 406                 tj9->last_poll_interval = poll_interval;
 407         }
 408 }
 409
 410 static void kxtj9_polled_input_open(struct input_polled_dev *dev)
 411 {
 412         struct kxtj9_data *tj9 = dev->private;
 413
 414         kxtj9_enable(tj9);
 415 }
 416
 417 static void kxtj9_polled_input_close(struct input_polled_dev *dev)
 418 {
 419         struct kxtj9_data *tj9 = dev->private;
 420
 421         kxtj9_disable(tj9);
 422 }
 423
 424 static int __devinit kxtj9_setup_polled_device(struct kxtj9_data *tj9)
 425 {
 426         int err;
 427         struct input_polled_dev *poll_dev;
 428         poll_dev = input_allocate_polled_device();
 429
 430         if (!poll_dev) {
 431                 dev_err(&tj9->client->dev,
 432                         "Failed to allocate polled device\n");
 433                 return -ENOMEM;
 434         }
 435
 436         tj9->poll_dev = poll_dev;
 437         tj9->input_dev = poll_dev->input;
 438
 439         poll_dev->private = tj9;
 440         poll_dev->poll = kxtj9_poll;
 441         poll_dev->open = kxtj9_polled_input_open;
 442         poll_dev->close = kxtj9_polled_input_close;
 443
 444         kxtj9_init_input_device(tj9, poll_dev->input);
 445
 446         err = input_register_polled_device(poll_dev);
 447         if (err) {
 448                 dev_err(&tj9->client->dev,
 449                         "Unable to register polled device, err=%d\n", err);
 450                 input_free_polled_device(poll_dev);
 451                 return err;
 452         }
 453
 454         return 0;
 455 }
 456
 457 static void __devexit kxtj9_teardown_polled_device(struct kxtj9_data *tj9)
 458 {
 459         input_unregister_polled_device(tj9->poll_dev);
 460         input_free_polled_device(tj9->poll_dev);
 461 }
 462
 463 #else
 464
 465 static inline int kxtj9_setup_polled_device(struct kxtj9_data *tj9)
 466 {
 467         return -ENOSYS;
 468 }
 469
 470 static inline void kxtj9_teardown_polled_device(struct kxtj9_data *tj9)
 471 {
 472 }
 473
 474 #endif
 475
 476 static int __devinit kxtj9_verify(struct kxtj9_data *tj9)
 477 {
 478         int retval;
 479
 480         retval = kxtj9_device_power_on(tj9);
 481         if (retval < 0)
 482                 return retval;
 483
 484         retval = i2c_smbus_read_byte_data(tj9->client, WHO_AM_I);
 485         if (retval < 0) {
 486                 dev_err(&tj9->client->dev, "read err int source\n");
 487                 goto out;
 488         }
 489
 490         retval = retval != 0x06 ? -EIO : 0;
 491
 492 out:
 493         kxtj9_device_power_off(tj9);
 494         return retval;
 495 }
 496
 497 static int __devinit kxtj9_probe(struct i2c_client *client,
 498                                  const struct i2c_device_id *id)
 499 {
 500         const struct kxtj9_platform_data *pdata = client->dev.platform_data;
 501         struct kxtj9_data *tj9;
 502         int err;
 503
 504         if (!i2c_check_functionality(client->adapter,
 505                                 I2C_FUNC_I2C | I2C_FUNC_SMBUS_BYTE_DATA)) {
 506                 dev_err(&client->dev, "client is not i2c capable\n");
 507                 return -ENXIO;
 508         }
 509
 510         if (!pdata) {
 511                 dev_err(&client->dev, "platform data is NULL; exiting\n");
 512                 return -EINVAL;
 513         }
 514
 515         tj9 = kzalloc(sizeof(*tj9), GFP_KERNEL);
 516         if (!tj9) {
 517                 dev_err(&client->dev,
 518                         "failed to allocate memory for module data\n");
 519                 return -ENOMEM;
 520         }
 521
 522         tj9->client = client;
 523         tj9->pdata = *pdata;
 524
 525         if (pdata->init) {
 526                 err = pdata->init();
 527                 if (err < 0)
 528                         goto err_free_mem;
 529         }
 530
 531         err = kxtj9_verify(tj9);
 532         if (err < 0) {
 533                 dev_err(&client->dev, "device not recognized\n");
 534                 goto err_pdata_exit;
 535         }
 536
 537         i2c_set_clientdata(client, tj9);
 538
 539         tj9->ctrl_reg1 = tj9->pdata.res_12bit | tj9->pdata.g_range;
 540         tj9->data_ctrl = tj9->pdata.data_odr_init;
 541
 542         if (client->irq) {
 543                 /* If in irq mode, populate INT_CTRL_REG1 and enable DRDY. */
 544                 tj9->int_ctrl |= KXTJ9_IEN | KXTJ9_IEA | KXTJ9_IEL;
 545                 tj9->ctrl_reg1 |= DRDYE;
 546
 547                 err = kxtj9_setup_input_device(tj9);
 548                 if (err)
 549                         goto err_pdata_exit;
 550
 551                 err = request_threaded_irq(client->irq, NULL, kxtj9_isr,
 552                                            IRQF_TRIGGER_RISING | IRQF_ONESHOT,
 553                                            "kxtj9-irq", tj9);
 554                 if (err) {
 555                         dev_err(&client->dev, "request irq failed: %d\n", err);
 556                         goto err_destroy_input;
 557                 }
 558
 559                 err = sysfs_create_group(&client->dev.kobj, &kxtj9_attribute_group);
 560                 if (err) {
 561                         dev_err(&client->dev, "sysfs create failed: %d\n", err);
 562                         goto err_free_irq;
 563                 }
 564
 565         } else {
 566                 err = kxtj9_setup_polled_device(tj9);
 567                 if (err)
 568                         goto err_pdata_exit;
 569         }
 570
 571         return 0;
 572
 573 err_free_irq:
 574         free_irq(client->irq, tj9);
 575 err_destroy_input:
 576         input_unregister_device(tj9->input_dev);
 577 err_pdata_exit:
 578         if (tj9->pdata.exit)
 579                 tj9->pdata.exit();
 580 err_free_mem:
 581         kfree(tj9);
 582         return err;
 583 }
 584
 585 static int __devexit kxtj9_remove(struct i2c_client *client)
 586 {
 587         struct kxtj9_data *tj9 = i2c_get_clientdata(client);
 588
 589         if (client->irq) {
 590                 sysfs_remove_group(&client->dev.kobj, &kxtj9_attribute_group);
 591                 free_irq(client->irq, tj9);
 592                 input_unregister_device(tj9->input_dev);
 593         } else {
 594                 kxtj9_teardown_polled_device(tj9);
 595         }
 596
 597         if (tj9->pdata.exit)
 598                 tj9->pdata.exit();
 599
 600         kfree(tj9);
 601
 602         return 0;
 603 }
 604
 605 #ifdef CONFIG_PM_SLEEP
 606 static int kxtj9_suspend(struct device *dev)
 607 {
 608         struct i2c_client *client = to_i2c_client(dev);
 609         struct kxtj9_data *tj9 = i2c_get_clientdata(client);
 610         struct input_dev *input_dev = tj9->input_dev;
 611
 612         mutex_lock(&input_dev->mutex);
 613
 614         if (input_dev->users)
 615                 kxtj9_disable(tj9);
 616
 617         mutex_unlock(&input_dev->mutex);
 618         return 0;
 619 }
 620
 621 static int kxtj9_resume(struct device *dev)
 622 {
 623         struct i2c_client *client = to_i2c_client(dev);
 624         struct kxtj9_data *tj9 = i2c_get_clientdata(client);
 625         struct input_dev *input_dev = tj9->input_dev;
 626         int retval = 0;
 627
 628         mutex_lock(&input_dev->mutex);
 629
 630         if (input_dev->users)
 631                 kxtj9_enable(tj9);
 632
 633         mutex_unlock(&input_dev->mutex);
 634         return retval;
 635 }
 636 #endif
 637
 638 static SIMPLE_DEV_PM_OPS(kxtj9_pm_ops, kxtj9_suspend, kxtj9_resume);
 639
 640 static const struct i2c_device_id kxtj9_id[] = {
 641         { NAME, 0 },
 642         { },
 643 };
 644
 645 MODULE_DEVICE_TABLE(i2c, kxtj9_id);
 646
 647 static struct i2c_driver kxtj9_driver = {
 648         .driver = {
 649                 .name   = NAME,
 650                 .owner  = THIS_MODULE,
 651                 .pm     = &kxtj9_pm_ops,
 652         },
 653         .probe          = kxtj9_probe,
 654         .remove         = __devexit_p(kxtj9_remove),
 655         .id_table       = kxtj9_id,
 656 };
 657
 658 static int __init kxtj9_init(void)
 659 {
 660         return i2c_add_driver(&kxtj9_driver);
 661 }
 662 module_init(kxtj9_init);
 663
 664 static void __exit kxtj9_exit(void)
 665 {
 666         i2c_del_driver(&kxtj9_driver);
 667 }
 668 module_exit(kxtj9_exit);
 669
 670 MODULE_DESCRIPTION("KXTJ9 accelerometer driver");
 671 MODULE_AUTHOR("Chris Hudson <chudson@kionix.com>");
 672 MODULE_LICENSE("GPL");