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