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 /* DATA CONTROL REGISTER BITS */ 45 #define ODR12_5F 0 46 #define ODR25F 1 47 #define ODR50F 2 48 #define ODR100F 3 49 #define ODR200F 4 50 #define ODR400F 5 51 #define ODR800F 6 52 /* INTERRUPT CONTROL REGISTER 1 BITS */ 53 /* Set these during probe if using irq mode */ 54 #define KXTJ9_IEL (1 << 3) 55 #define KXTJ9_IEA (1 << 4) 56 #define KXTJ9_IEN (1 << 5) 57 /* INPUT_ABS CONSTANTS */ 58 #define FUZZ 3 59 #define FLAT 3 60 /* RESUME STATE INDICES */ 61 #define RES_DATA_CTRL 0 62 #define RES_CTRL_REG1 1 63 #define RES_INT_CTRL1 2 64 #define RESUME_ENTRIES 3 65 66 /* 67 * The following table lists the maximum appropriate poll interval for each 68 * available output data rate. 69 */ 70 static const struct { 71 unsigned int cutoff; 72 u8 mask; 73 } kxtj9_odr_table[] = { 74 { 3, ODR800F }, 75 { 5, ODR400F }, 76 { 10, ODR200F }, 77 { 20, ODR100F }, 78 { 40, ODR50F }, 79 { 80, ODR25F }, 80 { 0, ODR12_5F}, 81 }; 82 83 struct kxtj9_data { 84 struct i2c_client *client; 85 struct kxtj9_platform_data pdata; 86 struct input_dev *input_dev; 87 #ifdef CONFIG_INPUT_KXTJ9_POLLED_MODE 88 struct input_polled_dev *poll_dev; 89 #endif 90 unsigned int last_poll_interval; 91 u8 shift; 92 u8 ctrl_reg1; 93 u8 data_ctrl; 94 u8 int_ctrl; 95 }; 96 97 static int kxtj9_i2c_read(struct kxtj9_data *tj9, u8 addr, u8 *data, int len) 98 { 99 struct i2c_msg msgs[] = { 100 { 101 .addr = tj9->client->addr, 102 .flags = tj9->client->flags, 103 .len = 1, 104 .buf = &addr, 105 }, 106 { 107 .addr = tj9->client->addr, 108 .flags = tj9->client->flags | I2C_M_RD, 109 .len = len, 110 .buf = data, 111 }, 112 }; 113 114 return i2c_transfer(tj9->client->adapter, msgs, 2); 115 } 116 117 static void kxtj9_report_acceleration_data(struct kxtj9_data *tj9) 118 { 119 s16 acc_data[3]; /* Data bytes from hardware xL, xH, yL, yH, zL, zH */ 120 s16 x, y, z; 121 int err; 122 123 err = kxtj9_i2c_read(tj9, XOUT_L, (u8 *)acc_data, 6); 124 if (err < 0) 125 dev_err(&tj9->client->dev, "accelerometer data read failed\n"); 126 127 x = le16_to_cpu(acc_data[tj9->pdata.axis_map_x]); 128 y = le16_to_cpu(acc_data[tj9->pdata.axis_map_y]); 129 z = le16_to_cpu(acc_data[tj9->pdata.axis_map_z]); 130 131 x >>= tj9->shift; 132 y >>= tj9->shift; 133 z >>= tj9->shift; 134 135 input_report_abs(tj9->input_dev, ABS_X, tj9->pdata.negate_x ? -x : x); 136 input_report_abs(tj9->input_dev, ABS_Y, tj9->pdata.negate_y ? -y : y); 137 input_report_abs(tj9->input_dev, ABS_Z, tj9->pdata.negate_z ? -z : z); 138 input_sync(tj9->input_dev); 139 } 140 141 static irqreturn_t kxtj9_isr(int irq, void *dev) 142 { 143 struct kxtj9_data *tj9 = dev; 144 int err; 145 146 /* data ready is the only possible interrupt type */ 147 kxtj9_report_acceleration_data(tj9); 148 149 err = i2c_smbus_read_byte_data(tj9->client, INT_REL); 150 if (err < 0) 151 dev_err(&tj9->client->dev, 152 "error clearing interrupt status: %d\n", err); 153 154 return IRQ_HANDLED; 155 } 156 157 static int kxtj9_update_g_range(struct kxtj9_data *tj9, u8 new_g_range) 158 { 159 switch (new_g_range) { 160 case KXTJ9_G_2G: 161 tj9->shift = 4; 162 break; 163 case KXTJ9_G_4G: 164 tj9->shift = 3; 165 break; 166 case KXTJ9_G_8G: 167 tj9->shift = 2; 168 break; 169 default: 170 return -EINVAL; 171 } 172 173 tj9->ctrl_reg1 &= 0xe7; 174 tj9->ctrl_reg1 |= new_g_range; 175 176 return 0; 177 } 178 179 static int kxtj9_update_odr(struct kxtj9_data *tj9, unsigned int poll_interval) 180 { 181 int err; 182 int i; 183 184 /* Use the lowest ODR that can support the requested poll interval */ 185 for (i = 0; i < ARRAY_SIZE(kxtj9_odr_table); i++) { 186 tj9->data_ctrl = kxtj9_odr_table[i].mask; 187 if (poll_interval < kxtj9_odr_table[i].cutoff) 188 break; 189 } 190 191 err = i2c_smbus_write_byte_data(tj9->client, CTRL_REG1, 0); 192 if (err < 0) 193 return err; 194 195 err = i2c_smbus_write_byte_data(tj9->client, DATA_CTRL, tj9->data_ctrl); 196 if (err < 0) 197 return err; 198 199 err = i2c_smbus_write_byte_data(tj9->client, CTRL_REG1, tj9->ctrl_reg1); 200 if (err < 0) 201 return err; 202 203 return 0; 204 } 205 206 static int kxtj9_device_power_on(struct kxtj9_data *tj9) 207 { 208 if (tj9->pdata.power_on) 209 return tj9->pdata.power_on(); 210 211 return 0; 212 } 213 214 static void kxtj9_device_power_off(struct kxtj9_data *tj9) 215 { 216 int err; 217 218 tj9->ctrl_reg1 &= PC1_OFF; 219 err = i2c_smbus_write_byte_data(tj9->client, CTRL_REG1, tj9->ctrl_reg1); 220 if (err < 0) 221 dev_err(&tj9->client->dev, "soft power off failed\n"); 222 223 if (tj9->pdata.power_off) 224 tj9->pdata.power_off(); 225 } 226 227 static int kxtj9_enable(struct kxtj9_data *tj9) 228 { 229 int err; 230 231 err = kxtj9_device_power_on(tj9); 232 if (err < 0) 233 return err; 234 235 /* ensure that PC1 is cleared before updating control registers */ 236 err = i2c_smbus_write_byte_data(tj9->client, CTRL_REG1, 0); 237 if (err < 0) 238 return err; 239 240 /* only write INT_CTRL_REG1 if in irq mode */ 241 if (tj9->client->irq) { 242 err = i2c_smbus_write_byte_data(tj9->client, 243 INT_CTRL1, tj9->int_ctrl); 244 if (err < 0) 245 return err; 246 } 247 248 err = kxtj9_update_g_range(tj9, tj9->pdata.g_range); 249 if (err < 0) 250 return err; 251 252 /* turn on outputs */ 253 tj9->ctrl_reg1 |= PC1_ON; 254 err = i2c_smbus_write_byte_data(tj9->client, CTRL_REG1, tj9->ctrl_reg1); 255 if (err < 0) 256 return err; 257 258 err = kxtj9_update_odr(tj9, tj9->last_poll_interval); 259 if (err < 0) 260 return err; 261 262 /* clear initial interrupt if in irq mode */ 263 if (tj9->client->irq) { 264 err = i2c_smbus_read_byte_data(tj9->client, INT_REL); 265 if (err < 0) { 266 dev_err(&tj9->client->dev, 267 "error clearing interrupt: %d\n", err); 268 goto fail; 269 } 270 } 271 272 return 0; 273 274 fail: 275 kxtj9_device_power_off(tj9); 276 return err; 277 } 278 279 static void kxtj9_disable(struct kxtj9_data *tj9) 280 { 281 kxtj9_device_power_off(tj9); 282 } 283 284 static int kxtj9_input_open(struct input_dev *input) 285 { 286 struct kxtj9_data *tj9 = input_get_drvdata(input); 287 288 return kxtj9_enable(tj9); 289 } 290 291 static void kxtj9_input_close(struct input_dev *dev) 292 { 293 struct kxtj9_data *tj9 = input_get_drvdata(dev); 294 295 kxtj9_disable(tj9); 296 } 297 298 static void kxtj9_init_input_device(struct kxtj9_data *tj9, 299 struct input_dev *input_dev) 300 { 301 __set_bit(EV_ABS, input_dev->evbit); 302 input_set_abs_params(input_dev, ABS_X, -G_MAX, G_MAX, FUZZ, FLAT); 303 input_set_abs_params(input_dev, ABS_Y, -G_MAX, G_MAX, FUZZ, FLAT); 304 input_set_abs_params(input_dev, ABS_Z, -G_MAX, G_MAX, FUZZ, FLAT); 305 306 input_dev->name = "kxtj9_accel"; 307 input_dev->id.bustype = BUS_I2C; 308 input_dev->dev.parent = &tj9->client->dev; 309 } 310 311 static int kxtj9_setup_input_device(struct kxtj9_data *tj9) 312 { 313 struct input_dev *input_dev; 314 int err; 315 316 input_dev = input_allocate_device(); 317 if (!input_dev) { 318 dev_err(&tj9->client->dev, "input device allocate failed\n"); 319 return -ENOMEM; 320 } 321 322 tj9->input_dev = input_dev; 323 324 input_dev->open = kxtj9_input_open; 325 input_dev->close = kxtj9_input_close; 326 input_set_drvdata(input_dev, tj9); 327 328 kxtj9_init_input_device(tj9, input_dev); 329 330 err = input_register_device(tj9->input_dev); 331 if (err) { 332 dev_err(&tj9->client->dev, 333 "unable to register input polled device %s: %d\n", 334 tj9->input_dev->name, err); 335 input_free_device(tj9->input_dev); 336 return err; 337 } 338 339 return 0; 340 } 341 342 /* 343 * When IRQ mode is selected, we need to provide an interface to allow the user 344 * to change the output data rate of the part. For consistency, we are using 345 * the set_poll method, which accepts a poll interval in milliseconds, and then 346 * calls update_odr() while passing this value as an argument. In IRQ mode, the 347 * data outputs will not be read AT the requested poll interval, rather, the 348 * lowest ODR that can support the requested interval. The client application 349 * will be responsible for retrieving data from the input node at the desired 350 * interval. 351 */ 352 353 /* Returns currently selected poll interval (in ms) */ 354 static ssize_t kxtj9_get_poll(struct device *dev, 355 struct device_attribute *attr, char *buf) 356 { 357 struct i2c_client *client = to_i2c_client(dev); 358 struct kxtj9_data *tj9 = i2c_get_clientdata(client); 359 360 return sprintf(buf, "%d\n", tj9->last_poll_interval); 361 } 362 363 /* Allow users to select a new poll interval (in ms) */ 364 static ssize_t kxtj9_set_poll(struct device *dev, struct device_attribute *attr, 365 const char *buf, size_t count) 366 { 367 struct i2c_client *client = to_i2c_client(dev); 368 struct kxtj9_data *tj9 = i2c_get_clientdata(client); 369 struct input_dev *input_dev = tj9->input_dev; 370 unsigned int interval; 371 int error; 372 373 error = kstrtouint(buf, 10, &interval); 374 if (error < 0) 375 return error; 376 377 /* Lock the device to prevent races with open/close (and itself) */ 378 mutex_lock(&input_dev->mutex); 379 380 disable_irq(client->irq); 381 382 /* 383 * Set current interval to the greater of the minimum interval or 384 * the requested interval 385 */ 386 tj9->last_poll_interval = max(interval, tj9->pdata.min_interval); 387 388 kxtj9_update_odr(tj9, tj9->last_poll_interval); 389 390 enable_irq(client->irq); 391 mutex_unlock(&input_dev->mutex); 392 393 return count; 394 } 395 396 static DEVICE_ATTR(poll, S_IRUGO|S_IWUSR, kxtj9_get_poll, kxtj9_set_poll); 397 398 static struct attribute *kxtj9_attributes[] = { 399 &dev_attr_poll.attr, 400 NULL 401 }; 402 403 static struct attribute_group kxtj9_attribute_group = { 404 .attrs = kxtj9_attributes 405 }; 406 407 408 #ifdef CONFIG_INPUT_KXTJ9_POLLED_MODE 409 static void kxtj9_poll(struct input_polled_dev *dev) 410 { 411 struct kxtj9_data *tj9 = dev->private; 412 unsigned int poll_interval = dev->poll_interval; 413 414 kxtj9_report_acceleration_data(tj9); 415 416 if (poll_interval != tj9->last_poll_interval) { 417 kxtj9_update_odr(tj9, poll_interval); 418 tj9->last_poll_interval = poll_interval; 419 } 420 } 421 422 static void kxtj9_polled_input_open(struct input_polled_dev *dev) 423 { 424 struct kxtj9_data *tj9 = dev->private; 425 426 kxtj9_enable(tj9); 427 } 428 429 static void kxtj9_polled_input_close(struct input_polled_dev *dev) 430 { 431 struct kxtj9_data *tj9 = dev->private; 432 433 kxtj9_disable(tj9); 434 } 435 436 static int kxtj9_setup_polled_device(struct kxtj9_data *tj9) 437 { 438 int err; 439 struct input_polled_dev *poll_dev; 440 poll_dev = input_allocate_polled_device(); 441 442 if (!poll_dev) { 443 dev_err(&tj9->client->dev, 444 "Failed to allocate polled device\n"); 445 return -ENOMEM; 446 } 447 448 tj9->poll_dev = poll_dev; 449 tj9->input_dev = poll_dev->input; 450 451 poll_dev->private = tj9; 452 poll_dev->poll = kxtj9_poll; 453 poll_dev->open = kxtj9_polled_input_open; 454 poll_dev->close = kxtj9_polled_input_close; 455 456 kxtj9_init_input_device(tj9, poll_dev->input); 457 458 err = input_register_polled_device(poll_dev); 459 if (err) { 460 dev_err(&tj9->client->dev, 461 "Unable to register polled device, err=%d\n", err); 462 input_free_polled_device(poll_dev); 463 return err; 464 } 465 466 return 0; 467 } 468 469 static void kxtj9_teardown_polled_device(struct kxtj9_data *tj9) 470 { 471 input_unregister_polled_device(tj9->poll_dev); 472 input_free_polled_device(tj9->poll_dev); 473 } 474 475 #else 476 477 static inline int kxtj9_setup_polled_device(struct kxtj9_data *tj9) 478 { 479 return -ENOSYS; 480 } 481 482 static inline void kxtj9_teardown_polled_device(struct kxtj9_data *tj9) 483 { 484 } 485 486 #endif 487 488 static int kxtj9_verify(struct kxtj9_data *tj9) 489 { 490 int retval; 491 492 retval = kxtj9_device_power_on(tj9); 493 if (retval < 0) 494 return retval; 495 496 retval = i2c_smbus_read_byte_data(tj9->client, WHO_AM_I); 497 if (retval < 0) { 498 dev_err(&tj9->client->dev, "read err int source\n"); 499 goto out; 500 } 501 502 retval = (retval != 0x07 && retval != 0x08) ? -EIO : 0; 503 504 out: 505 kxtj9_device_power_off(tj9); 506 return retval; 507 } 508 509 static int kxtj9_probe(struct i2c_client *client, 510 const struct i2c_device_id *id) 511 { 512 const struct kxtj9_platform_data *pdata = 513 dev_get_platdata(&client->dev); 514 struct kxtj9_data *tj9; 515 int err; 516 517 if (!i2c_check_functionality(client->adapter, 518 I2C_FUNC_I2C | I2C_FUNC_SMBUS_BYTE_DATA)) { 519 dev_err(&client->dev, "client is not i2c capable\n"); 520 return -ENXIO; 521 } 522 523 if (!pdata) { 524 dev_err(&client->dev, "platform data is NULL; exiting\n"); 525 return -EINVAL; 526 } 527 528 tj9 = kzalloc(sizeof(*tj9), GFP_KERNEL); 529 if (!tj9) { 530 dev_err(&client->dev, 531 "failed to allocate memory for module data\n"); 532 return -ENOMEM; 533 } 534 535 tj9->client = client; 536 tj9->pdata = *pdata; 537 538 if (pdata->init) { 539 err = pdata->init(); 540 if (err < 0) 541 goto err_free_mem; 542 } 543 544 err = kxtj9_verify(tj9); 545 if (err < 0) { 546 dev_err(&client->dev, "device not recognized\n"); 547 goto err_pdata_exit; 548 } 549 550 i2c_set_clientdata(client, tj9); 551 552 tj9->ctrl_reg1 = tj9->pdata.res_12bit | tj9->pdata.g_range; 553 tj9->last_poll_interval = tj9->pdata.init_interval; 554 555 if (client->irq) { 556 /* If in irq mode, populate INT_CTRL_REG1 and enable DRDY. */ 557 tj9->int_ctrl |= KXTJ9_IEN | KXTJ9_IEA | KXTJ9_IEL; 558 tj9->ctrl_reg1 |= DRDYE; 559 560 err = kxtj9_setup_input_device(tj9); 561 if (err) 562 goto err_pdata_exit; 563 564 err = request_threaded_irq(client->irq, NULL, kxtj9_isr, 565 IRQF_TRIGGER_RISING | IRQF_ONESHOT, 566 "kxtj9-irq", tj9); 567 if (err) { 568 dev_err(&client->dev, "request irq failed: %d\n", err); 569 goto err_destroy_input; 570 } 571 572 err = sysfs_create_group(&client->dev.kobj, &kxtj9_attribute_group); 573 if (err) { 574 dev_err(&client->dev, "sysfs create failed: %d\n", err); 575 goto err_free_irq; 576 } 577 578 } else { 579 err = kxtj9_setup_polled_device(tj9); 580 if (err) 581 goto err_pdata_exit; 582 } 583 584 return 0; 585 586 err_free_irq: 587 free_irq(client->irq, tj9); 588 err_destroy_input: 589 input_unregister_device(tj9->input_dev); 590 err_pdata_exit: 591 if (tj9->pdata.exit) 592 tj9->pdata.exit(); 593 err_free_mem: 594 kfree(tj9); 595 return err; 596 } 597 598 static int kxtj9_remove(struct i2c_client *client) 599 { 600 struct kxtj9_data *tj9 = i2c_get_clientdata(client); 601 602 if (client->irq) { 603 sysfs_remove_group(&client->dev.kobj, &kxtj9_attribute_group); 604 free_irq(client->irq, tj9); 605 input_unregister_device(tj9->input_dev); 606 } else { 607 kxtj9_teardown_polled_device(tj9); 608 } 609 610 if (tj9->pdata.exit) 611 tj9->pdata.exit(); 612 613 kfree(tj9); 614 615 return 0; 616 } 617 618 static int __maybe_unused kxtj9_suspend(struct device *dev) 619 { 620 struct i2c_client *client = to_i2c_client(dev); 621 struct kxtj9_data *tj9 = i2c_get_clientdata(client); 622 struct input_dev *input_dev = tj9->input_dev; 623 624 mutex_lock(&input_dev->mutex); 625 626 if (input_dev->users) 627 kxtj9_disable(tj9); 628 629 mutex_unlock(&input_dev->mutex); 630 return 0; 631 } 632 633 static int __maybe_unused kxtj9_resume(struct device *dev) 634 { 635 struct i2c_client *client = to_i2c_client(dev); 636 struct kxtj9_data *tj9 = i2c_get_clientdata(client); 637 struct input_dev *input_dev = tj9->input_dev; 638 int retval = 0; 639 640 mutex_lock(&input_dev->mutex); 641 642 if (input_dev->users) 643 kxtj9_enable(tj9); 644 645 mutex_unlock(&input_dev->mutex); 646 return retval; 647 } 648 649 static SIMPLE_DEV_PM_OPS(kxtj9_pm_ops, kxtj9_suspend, kxtj9_resume); 650 651 static const struct i2c_device_id kxtj9_id[] = { 652 { NAME, 0 }, 653 { }, 654 }; 655 656 MODULE_DEVICE_TABLE(i2c, kxtj9_id); 657 658 static struct i2c_driver kxtj9_driver = { 659 .driver = { 660 .name = NAME, 661 .pm = &kxtj9_pm_ops, 662 }, 663 .probe = kxtj9_probe, 664 .remove = kxtj9_remove, 665 .id_table = kxtj9_id, 666 }; 667 668 module_i2c_driver(kxtj9_driver); 669 670 MODULE_DESCRIPTION("KXTJ9 accelerometer driver"); 671 MODULE_AUTHOR("Chris Hudson <chudson@kionix.com>"); 672 MODULE_LICENSE("GPL"); 673