1 /* 2 * Driver for the Asahi Kasei EMD Corporation AK8974 3 * and Aichi Steel AMI305 magnetometer chips. 4 * Based on a patch from Samu Onkalo and the AK8975 IIO driver. 5 * 6 * Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies). 7 * Copyright (c) 2010 NVIDIA Corporation. 8 * Copyright (C) 2016 Linaro Ltd. 9 * 10 * Author: Samu Onkalo <samu.p.onkalo@nokia.com> 11 * Author: Linus Walleij <linus.walleij@linaro.org> 12 */ 13 #include <linux/module.h> 14 #include <linux/kernel.h> 15 #include <linux/i2c.h> 16 #include <linux/interrupt.h> 17 #include <linux/irq.h> /* For irq_get_irq_data() */ 18 #include <linux/completion.h> 19 #include <linux/err.h> 20 #include <linux/mutex.h> 21 #include <linux/delay.h> 22 #include <linux/bitops.h> 23 #include <linux/regmap.h> 24 #include <linux/regulator/consumer.h> 25 #include <linux/pm_runtime.h> 26 27 #include <linux/iio/iio.h> 28 #include <linux/iio/sysfs.h> 29 #include <linux/iio/buffer.h> 30 #include <linux/iio/trigger.h> 31 #include <linux/iio/trigger_consumer.h> 32 #include <linux/iio/triggered_buffer.h> 33 34 /* 35 * 16-bit registers are little-endian. LSB is at the address defined below 36 * and MSB is at the next higher address. 37 */ 38 39 /* These registers are common for AK8974 and AMI305 */ 40 #define AK8974_SELFTEST 0x0C 41 #define AK8974_SELFTEST_IDLE 0x55 42 #define AK8974_SELFTEST_OK 0xAA 43 44 #define AK8974_INFO 0x0D 45 46 #define AK8974_WHOAMI 0x0F 47 #define AK8974_WHOAMI_VALUE_AMI305 0x47 48 #define AK8974_WHOAMI_VALUE_AK8974 0x48 49 50 #define AK8974_DATA_X 0x10 51 #define AK8974_DATA_Y 0x12 52 #define AK8974_DATA_Z 0x14 53 #define AK8974_INT_SRC 0x16 54 #define AK8974_STATUS 0x18 55 #define AK8974_INT_CLEAR 0x1A 56 #define AK8974_CTRL1 0x1B 57 #define AK8974_CTRL2 0x1C 58 #define AK8974_CTRL3 0x1D 59 #define AK8974_INT_CTRL 0x1E 60 #define AK8974_INT_THRES 0x26 /* Absolute any axis value threshold */ 61 #define AK8974_PRESET 0x30 62 63 /* AK8974-specific offsets */ 64 #define AK8974_OFFSET_X 0x20 65 #define AK8974_OFFSET_Y 0x22 66 #define AK8974_OFFSET_Z 0x24 67 /* AMI305-specific offsets */ 68 #define AMI305_OFFSET_X 0x6C 69 #define AMI305_OFFSET_Y 0x72 70 #define AMI305_OFFSET_Z 0x78 71 72 /* Different temperature registers */ 73 #define AK8974_TEMP 0x31 74 #define AMI305_TEMP 0x60 75 76 #define AK8974_INT_X_HIGH BIT(7) /* Axis over +threshold */ 77 #define AK8974_INT_Y_HIGH BIT(6) 78 #define AK8974_INT_Z_HIGH BIT(5) 79 #define AK8974_INT_X_LOW BIT(4) /* Axis below -threshold */ 80 #define AK8974_INT_Y_LOW BIT(3) 81 #define AK8974_INT_Z_LOW BIT(2) 82 #define AK8974_INT_RANGE BIT(1) /* Range overflow (any axis) */ 83 84 #define AK8974_STATUS_DRDY BIT(6) /* Data ready */ 85 #define AK8974_STATUS_OVERRUN BIT(5) /* Data overrun */ 86 #define AK8974_STATUS_INT BIT(4) /* Interrupt occurred */ 87 88 #define AK8974_CTRL1_POWER BIT(7) /* 0 = standby; 1 = active */ 89 #define AK8974_CTRL1_RATE BIT(4) /* 0 = 10 Hz; 1 = 20 Hz */ 90 #define AK8974_CTRL1_FORCE_EN BIT(1) /* 0 = normal; 1 = force */ 91 #define AK8974_CTRL1_MODE2 BIT(0) /* 0 */ 92 93 #define AK8974_CTRL2_INT_EN BIT(4) /* 1 = enable interrupts */ 94 #define AK8974_CTRL2_DRDY_EN BIT(3) /* 1 = enable data ready signal */ 95 #define AK8974_CTRL2_DRDY_POL BIT(2) /* 1 = data ready active high */ 96 #define AK8974_CTRL2_RESDEF (AK8974_CTRL2_DRDY_POL) 97 98 #define AK8974_CTRL3_RESET BIT(7) /* Software reset */ 99 #define AK8974_CTRL3_FORCE BIT(6) /* Start forced measurement */ 100 #define AK8974_CTRL3_SELFTEST BIT(4) /* Set selftest register */ 101 #define AK8974_CTRL3_RESDEF 0x00 102 103 #define AK8974_INT_CTRL_XEN BIT(7) /* Enable interrupt for this axis */ 104 #define AK8974_INT_CTRL_YEN BIT(6) 105 #define AK8974_INT_CTRL_ZEN BIT(5) 106 #define AK8974_INT_CTRL_XYZEN (BIT(7)|BIT(6)|BIT(5)) 107 #define AK8974_INT_CTRL_POL BIT(3) /* 0 = active low; 1 = active high */ 108 #define AK8974_INT_CTRL_PULSE BIT(1) /* 0 = latched; 1 = pulse (50 usec) */ 109 #define AK8974_INT_CTRL_RESDEF (AK8974_INT_CTRL_XYZEN | AK8974_INT_CTRL_POL) 110 111 /* The AMI305 has elaborate FW version and serial number registers */ 112 #define AMI305_VER 0xE8 113 #define AMI305_SN 0xEA 114 115 #define AK8974_MAX_RANGE 2048 116 117 #define AK8974_POWERON_DELAY 50 118 #define AK8974_ACTIVATE_DELAY 1 119 #define AK8974_SELFTEST_DELAY 1 120 /* 121 * Set the autosuspend to two orders of magnitude larger than the poweron 122 * delay to make sane reasonable power tradeoff savings (5 seconds in 123 * this case). 124 */ 125 #define AK8974_AUTOSUSPEND_DELAY 5000 126 127 #define AK8974_MEASTIME 3 128 129 #define AK8974_PWR_ON 1 130 #define AK8974_PWR_OFF 0 131 132 /** 133 * struct ak8974 - state container for the AK8974 driver 134 * @i2c: parent I2C client 135 * @orientation: mounting matrix, flipped axis etc 136 * @map: regmap to access the AK8974 registers over I2C 137 * @regs: the avdd and dvdd power regulators 138 * @name: the name of the part 139 * @variant: the whoami ID value (for selecting code paths) 140 * @lock: locks the magnetometer for exclusive use during a measurement 141 * @drdy_irq: uses the DRDY IRQ line 142 * @drdy_complete: completion for DRDY 143 * @drdy_active_low: the DRDY IRQ is active low 144 */ 145 struct ak8974 { 146 struct i2c_client *i2c; 147 struct iio_mount_matrix orientation; 148 struct regmap *map; 149 struct regulator_bulk_data regs[2]; 150 const char *name; 151 u8 variant; 152 struct mutex lock; 153 bool drdy_irq; 154 struct completion drdy_complete; 155 bool drdy_active_low; 156 }; 157 158 static const char ak8974_reg_avdd[] = "avdd"; 159 static const char ak8974_reg_dvdd[] = "dvdd"; 160 161 static int ak8974_set_power(struct ak8974 *ak8974, bool mode) 162 { 163 int ret; 164 u8 val; 165 166 val = mode ? AK8974_CTRL1_POWER : 0; 167 val |= AK8974_CTRL1_FORCE_EN; 168 ret = regmap_write(ak8974->map, AK8974_CTRL1, val); 169 if (ret < 0) 170 return ret; 171 172 if (mode) 173 msleep(AK8974_ACTIVATE_DELAY); 174 175 return 0; 176 } 177 178 static int ak8974_reset(struct ak8974 *ak8974) 179 { 180 int ret; 181 182 /* Power on to get register access. Sets CTRL1 reg to reset state */ 183 ret = ak8974_set_power(ak8974, AK8974_PWR_ON); 184 if (ret) 185 return ret; 186 ret = regmap_write(ak8974->map, AK8974_CTRL2, AK8974_CTRL2_RESDEF); 187 if (ret) 188 return ret; 189 ret = regmap_write(ak8974->map, AK8974_CTRL3, AK8974_CTRL3_RESDEF); 190 if (ret) 191 return ret; 192 ret = regmap_write(ak8974->map, AK8974_INT_CTRL, 193 AK8974_INT_CTRL_RESDEF); 194 if (ret) 195 return ret; 196 197 /* After reset, power off is default state */ 198 return ak8974_set_power(ak8974, AK8974_PWR_OFF); 199 } 200 201 static int ak8974_configure(struct ak8974 *ak8974) 202 { 203 int ret; 204 205 ret = regmap_write(ak8974->map, AK8974_CTRL2, AK8974_CTRL2_DRDY_EN | 206 AK8974_CTRL2_INT_EN); 207 if (ret) 208 return ret; 209 ret = regmap_write(ak8974->map, AK8974_CTRL3, 0); 210 if (ret) 211 return ret; 212 ret = regmap_write(ak8974->map, AK8974_INT_CTRL, AK8974_INT_CTRL_POL); 213 if (ret) 214 return ret; 215 216 return regmap_write(ak8974->map, AK8974_PRESET, 0); 217 } 218 219 static int ak8974_trigmeas(struct ak8974 *ak8974) 220 { 221 unsigned int clear; 222 u8 mask; 223 u8 val; 224 int ret; 225 226 /* Clear any previous measurement overflow status */ 227 ret = regmap_read(ak8974->map, AK8974_INT_CLEAR, &clear); 228 if (ret) 229 return ret; 230 231 /* If we have a DRDY IRQ line, use it */ 232 if (ak8974->drdy_irq) { 233 mask = AK8974_CTRL2_INT_EN | 234 AK8974_CTRL2_DRDY_EN | 235 AK8974_CTRL2_DRDY_POL; 236 val = AK8974_CTRL2_DRDY_EN; 237 238 if (!ak8974->drdy_active_low) 239 val |= AK8974_CTRL2_DRDY_POL; 240 241 init_completion(&ak8974->drdy_complete); 242 ret = regmap_update_bits(ak8974->map, AK8974_CTRL2, 243 mask, val); 244 if (ret) 245 return ret; 246 } 247 248 /* Force a measurement */ 249 return regmap_update_bits(ak8974->map, 250 AK8974_CTRL3, 251 AK8974_CTRL3_FORCE, 252 AK8974_CTRL3_FORCE); 253 } 254 255 static int ak8974_await_drdy(struct ak8974 *ak8974) 256 { 257 int timeout = 2; 258 unsigned int val; 259 int ret; 260 261 if (ak8974->drdy_irq) { 262 ret = wait_for_completion_timeout(&ak8974->drdy_complete, 263 1 + msecs_to_jiffies(1000)); 264 if (!ret) { 265 dev_err(&ak8974->i2c->dev, 266 "timeout waiting for DRDY IRQ\n"); 267 return -ETIMEDOUT; 268 } 269 return 0; 270 } 271 272 /* Default delay-based poll loop */ 273 do { 274 msleep(AK8974_MEASTIME); 275 ret = regmap_read(ak8974->map, AK8974_STATUS, &val); 276 if (ret < 0) 277 return ret; 278 if (val & AK8974_STATUS_DRDY) 279 return 0; 280 } while (--timeout); 281 282 dev_err(&ak8974->i2c->dev, "timeout waiting for DRDY\n"); 283 return -ETIMEDOUT; 284 } 285 286 static int ak8974_getresult(struct ak8974 *ak8974, __le16 *result) 287 { 288 unsigned int src; 289 int ret; 290 291 ret = ak8974_await_drdy(ak8974); 292 if (ret) 293 return ret; 294 ret = regmap_read(ak8974->map, AK8974_INT_SRC, &src); 295 if (ret < 0) 296 return ret; 297 298 /* Out of range overflow! Strong magnet close? */ 299 if (src & AK8974_INT_RANGE) { 300 dev_err(&ak8974->i2c->dev, 301 "range overflow in sensor\n"); 302 return -ERANGE; 303 } 304 305 ret = regmap_bulk_read(ak8974->map, AK8974_DATA_X, result, 6); 306 if (ret) 307 return ret; 308 309 return ret; 310 } 311 312 static irqreturn_t ak8974_drdy_irq(int irq, void *d) 313 { 314 struct ak8974 *ak8974 = d; 315 316 if (!ak8974->drdy_irq) 317 return IRQ_NONE; 318 319 /* TODO: timestamp here to get good measurement stamps */ 320 return IRQ_WAKE_THREAD; 321 } 322 323 static irqreturn_t ak8974_drdy_irq_thread(int irq, void *d) 324 { 325 struct ak8974 *ak8974 = d; 326 unsigned int val; 327 int ret; 328 329 /* Check if this was a DRDY from us */ 330 ret = regmap_read(ak8974->map, AK8974_STATUS, &val); 331 if (ret < 0) { 332 dev_err(&ak8974->i2c->dev, "error reading DRDY status\n"); 333 return IRQ_HANDLED; 334 } 335 if (val & AK8974_STATUS_DRDY) { 336 /* Yes this was our IRQ */ 337 complete(&ak8974->drdy_complete); 338 return IRQ_HANDLED; 339 } 340 341 /* We may be on a shared IRQ, let the next client check */ 342 return IRQ_NONE; 343 } 344 345 static int ak8974_selftest(struct ak8974 *ak8974) 346 { 347 struct device *dev = &ak8974->i2c->dev; 348 unsigned int val; 349 int ret; 350 351 ret = regmap_read(ak8974->map, AK8974_SELFTEST, &val); 352 if (ret) 353 return ret; 354 if (val != AK8974_SELFTEST_IDLE) { 355 dev_err(dev, "selftest not idle before test\n"); 356 return -EIO; 357 } 358 359 /* Trigger self-test */ 360 ret = regmap_update_bits(ak8974->map, 361 AK8974_CTRL3, 362 AK8974_CTRL3_SELFTEST, 363 AK8974_CTRL3_SELFTEST); 364 if (ret) { 365 dev_err(dev, "could not write CTRL3\n"); 366 return ret; 367 } 368 369 msleep(AK8974_SELFTEST_DELAY); 370 371 ret = regmap_read(ak8974->map, AK8974_SELFTEST, &val); 372 if (ret) 373 return ret; 374 if (val != AK8974_SELFTEST_OK) { 375 dev_err(dev, "selftest result NOT OK (%02x)\n", val); 376 return -EIO; 377 } 378 379 ret = regmap_read(ak8974->map, AK8974_SELFTEST, &val); 380 if (ret) 381 return ret; 382 if (val != AK8974_SELFTEST_IDLE) { 383 dev_err(dev, "selftest not idle after test (%02x)\n", val); 384 return -EIO; 385 } 386 dev_dbg(dev, "passed self-test\n"); 387 388 return 0; 389 } 390 391 static int ak8974_get_u16_val(struct ak8974 *ak8974, u8 reg, u16 *val) 392 { 393 int ret; 394 __le16 bulk; 395 396 ret = regmap_bulk_read(ak8974->map, reg, &bulk, 2); 397 if (ret) 398 return ret; 399 *val = le16_to_cpu(bulk); 400 401 return 0; 402 } 403 404 static int ak8974_detect(struct ak8974 *ak8974) 405 { 406 unsigned int whoami; 407 const char *name; 408 int ret; 409 unsigned int fw; 410 u16 sn; 411 412 ret = regmap_read(ak8974->map, AK8974_WHOAMI, &whoami); 413 if (ret) 414 return ret; 415 416 switch (whoami) { 417 case AK8974_WHOAMI_VALUE_AMI305: 418 name = "ami305"; 419 ret = regmap_read(ak8974->map, AMI305_VER, &fw); 420 if (ret) 421 return ret; 422 fw &= 0x7f; /* only bits 0 thru 6 valid */ 423 ret = ak8974_get_u16_val(ak8974, AMI305_SN, &sn); 424 if (ret) 425 return ret; 426 dev_info(&ak8974->i2c->dev, 427 "detected %s, FW ver %02x, S/N: %04x\n", 428 name, fw, sn); 429 break; 430 case AK8974_WHOAMI_VALUE_AK8974: 431 name = "ak8974"; 432 dev_info(&ak8974->i2c->dev, "detected AK8974\n"); 433 break; 434 default: 435 dev_err(&ak8974->i2c->dev, "unsupported device (%02x) ", 436 whoami); 437 return -ENODEV; 438 } 439 440 ak8974->name = name; 441 ak8974->variant = whoami; 442 443 return 0; 444 } 445 446 static int ak8974_read_raw(struct iio_dev *indio_dev, 447 struct iio_chan_spec const *chan, 448 int *val, int *val2, 449 long mask) 450 { 451 struct ak8974 *ak8974 = iio_priv(indio_dev); 452 __le16 hw_values[3]; 453 int ret = -EINVAL; 454 455 pm_runtime_get_sync(&ak8974->i2c->dev); 456 mutex_lock(&ak8974->lock); 457 458 switch (mask) { 459 case IIO_CHAN_INFO_RAW: 460 if (chan->address > 2) { 461 dev_err(&ak8974->i2c->dev, "faulty channel address\n"); 462 ret = -EIO; 463 goto out_unlock; 464 } 465 ret = ak8974_trigmeas(ak8974); 466 if (ret) 467 goto out_unlock; 468 ret = ak8974_getresult(ak8974, hw_values); 469 if (ret) 470 goto out_unlock; 471 472 /* 473 * We read all axes and discard all but one, for optimized 474 * reading, use the triggered buffer. 475 */ 476 *val = le16_to_cpu(hw_values[chan->address]); 477 478 ret = IIO_VAL_INT; 479 } 480 481 out_unlock: 482 mutex_unlock(&ak8974->lock); 483 pm_runtime_mark_last_busy(&ak8974->i2c->dev); 484 pm_runtime_put_autosuspend(&ak8974->i2c->dev); 485 486 return ret; 487 } 488 489 static void ak8974_fill_buffer(struct iio_dev *indio_dev) 490 { 491 struct ak8974 *ak8974 = iio_priv(indio_dev); 492 int ret; 493 __le16 hw_values[8]; /* Three axes + 64bit padding */ 494 495 pm_runtime_get_sync(&ak8974->i2c->dev); 496 mutex_lock(&ak8974->lock); 497 498 ret = ak8974_trigmeas(ak8974); 499 if (ret) { 500 dev_err(&ak8974->i2c->dev, "error triggering measure\n"); 501 goto out_unlock; 502 } 503 ret = ak8974_getresult(ak8974, hw_values); 504 if (ret) { 505 dev_err(&ak8974->i2c->dev, "error getting measures\n"); 506 goto out_unlock; 507 } 508 509 iio_push_to_buffers_with_timestamp(indio_dev, hw_values, 510 iio_get_time_ns(indio_dev)); 511 512 out_unlock: 513 mutex_unlock(&ak8974->lock); 514 pm_runtime_mark_last_busy(&ak8974->i2c->dev); 515 pm_runtime_put_autosuspend(&ak8974->i2c->dev); 516 } 517 518 static irqreturn_t ak8974_handle_trigger(int irq, void *p) 519 { 520 const struct iio_poll_func *pf = p; 521 struct iio_dev *indio_dev = pf->indio_dev; 522 523 ak8974_fill_buffer(indio_dev); 524 iio_trigger_notify_done(indio_dev->trig); 525 526 return IRQ_HANDLED; 527 } 528 529 static const struct iio_mount_matrix * 530 ak8974_get_mount_matrix(const struct iio_dev *indio_dev, 531 const struct iio_chan_spec *chan) 532 { 533 struct ak8974 *ak8974 = iio_priv(indio_dev); 534 535 return &ak8974->orientation; 536 } 537 538 static const struct iio_chan_spec_ext_info ak8974_ext_info[] = { 539 IIO_MOUNT_MATRIX(IIO_SHARED_BY_DIR, ak8974_get_mount_matrix), 540 { }, 541 }; 542 543 #define AK8974_AXIS_CHANNEL(axis, index) \ 544 { \ 545 .type = IIO_MAGN, \ 546 .modified = 1, \ 547 .channel2 = IIO_MOD_##axis, \ 548 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ 549 .ext_info = ak8974_ext_info, \ 550 .address = index, \ 551 .scan_index = index, \ 552 .scan_type = { \ 553 .sign = 's', \ 554 .realbits = 16, \ 555 .storagebits = 16, \ 556 .endianness = IIO_LE \ 557 }, \ 558 } 559 560 static const struct iio_chan_spec ak8974_channels[] = { 561 AK8974_AXIS_CHANNEL(X, 0), 562 AK8974_AXIS_CHANNEL(Y, 1), 563 AK8974_AXIS_CHANNEL(Z, 2), 564 IIO_CHAN_SOFT_TIMESTAMP(3), 565 }; 566 567 static const unsigned long ak8974_scan_masks[] = { 0x7, 0 }; 568 569 static const struct iio_info ak8974_info = { 570 .read_raw = &ak8974_read_raw, 571 .driver_module = THIS_MODULE, 572 }; 573 574 static bool ak8974_writeable_reg(struct device *dev, unsigned int reg) 575 { 576 struct i2c_client *i2c = to_i2c_client(dev); 577 struct iio_dev *indio_dev = i2c_get_clientdata(i2c); 578 struct ak8974 *ak8974 = iio_priv(indio_dev); 579 580 switch (reg) { 581 case AK8974_CTRL1: 582 case AK8974_CTRL2: 583 case AK8974_CTRL3: 584 case AK8974_INT_CTRL: 585 case AK8974_INT_THRES: 586 case AK8974_INT_THRES + 1: 587 case AK8974_PRESET: 588 case AK8974_PRESET + 1: 589 return true; 590 case AK8974_OFFSET_X: 591 case AK8974_OFFSET_X + 1: 592 case AK8974_OFFSET_Y: 593 case AK8974_OFFSET_Y + 1: 594 case AK8974_OFFSET_Z: 595 case AK8974_OFFSET_Z + 1: 596 if (ak8974->variant == AK8974_WHOAMI_VALUE_AK8974) 597 return true; 598 return false; 599 case AMI305_OFFSET_X: 600 case AMI305_OFFSET_X + 1: 601 case AMI305_OFFSET_Y: 602 case AMI305_OFFSET_Y + 1: 603 case AMI305_OFFSET_Z: 604 case AMI305_OFFSET_Z + 1: 605 if (ak8974->variant == AK8974_WHOAMI_VALUE_AMI305) 606 return true; 607 return false; 608 default: 609 return false; 610 } 611 } 612 613 static const struct regmap_config ak8974_regmap_config = { 614 .reg_bits = 8, 615 .val_bits = 8, 616 .max_register = 0xff, 617 .writeable_reg = ak8974_writeable_reg, 618 }; 619 620 static int ak8974_probe(struct i2c_client *i2c, 621 const struct i2c_device_id *id) 622 { 623 struct iio_dev *indio_dev; 624 struct ak8974 *ak8974; 625 unsigned long irq_trig; 626 int irq = i2c->irq; 627 int ret; 628 629 /* Register with IIO */ 630 indio_dev = devm_iio_device_alloc(&i2c->dev, sizeof(*ak8974)); 631 if (indio_dev == NULL) 632 return -ENOMEM; 633 634 ak8974 = iio_priv(indio_dev); 635 i2c_set_clientdata(i2c, indio_dev); 636 ak8974->i2c = i2c; 637 mutex_init(&ak8974->lock); 638 639 ret = of_iio_read_mount_matrix(&i2c->dev, 640 "mount-matrix", 641 &ak8974->orientation); 642 if (ret) 643 return ret; 644 645 ak8974->regs[0].supply = ak8974_reg_avdd; 646 ak8974->regs[1].supply = ak8974_reg_dvdd; 647 648 ret = devm_regulator_bulk_get(&i2c->dev, 649 ARRAY_SIZE(ak8974->regs), 650 ak8974->regs); 651 if (ret < 0) { 652 dev_err(&i2c->dev, "cannot get regulators\n"); 653 return ret; 654 } 655 656 ret = regulator_bulk_enable(ARRAY_SIZE(ak8974->regs), ak8974->regs); 657 if (ret < 0) { 658 dev_err(&i2c->dev, "cannot enable regulators\n"); 659 return ret; 660 } 661 662 /* Take runtime PM online */ 663 pm_runtime_get_noresume(&i2c->dev); 664 pm_runtime_set_active(&i2c->dev); 665 pm_runtime_enable(&i2c->dev); 666 667 ak8974->map = devm_regmap_init_i2c(i2c, &ak8974_regmap_config); 668 if (IS_ERR(ak8974->map)) { 669 dev_err(&i2c->dev, "failed to allocate register map\n"); 670 return PTR_ERR(ak8974->map); 671 } 672 673 ret = ak8974_set_power(ak8974, AK8974_PWR_ON); 674 if (ret) { 675 dev_err(&i2c->dev, "could not power on\n"); 676 goto power_off; 677 } 678 679 ret = ak8974_detect(ak8974); 680 if (ret) { 681 dev_err(&i2c->dev, "neither AK8974 nor AMI305 found\n"); 682 goto power_off; 683 } 684 685 ret = ak8974_selftest(ak8974); 686 if (ret) 687 dev_err(&i2c->dev, "selftest failed (continuing anyway)\n"); 688 689 ret = ak8974_reset(ak8974); 690 if (ret) { 691 dev_err(&i2c->dev, "AK8974 reset failed\n"); 692 goto power_off; 693 } 694 695 pm_runtime_set_autosuspend_delay(&i2c->dev, 696 AK8974_AUTOSUSPEND_DELAY); 697 pm_runtime_use_autosuspend(&i2c->dev); 698 pm_runtime_put(&i2c->dev); 699 700 indio_dev->dev.parent = &i2c->dev; 701 indio_dev->channels = ak8974_channels; 702 indio_dev->num_channels = ARRAY_SIZE(ak8974_channels); 703 indio_dev->info = &ak8974_info; 704 indio_dev->available_scan_masks = ak8974_scan_masks; 705 indio_dev->modes = INDIO_DIRECT_MODE; 706 indio_dev->name = ak8974->name; 707 708 ret = iio_triggered_buffer_setup(indio_dev, NULL, 709 ak8974_handle_trigger, 710 NULL); 711 if (ret) { 712 dev_err(&i2c->dev, "triggered buffer setup failed\n"); 713 goto disable_pm; 714 } 715 716 /* If we have a valid DRDY IRQ, make use of it */ 717 if (irq > 0) { 718 irq_trig = irqd_get_trigger_type(irq_get_irq_data(irq)); 719 if (irq_trig == IRQF_TRIGGER_RISING) { 720 dev_info(&i2c->dev, "enable rising edge DRDY IRQ\n"); 721 } else if (irq_trig == IRQF_TRIGGER_FALLING) { 722 ak8974->drdy_active_low = true; 723 dev_info(&i2c->dev, "enable falling edge DRDY IRQ\n"); 724 } else { 725 irq_trig = IRQF_TRIGGER_RISING; 726 } 727 irq_trig |= IRQF_ONESHOT; 728 irq_trig |= IRQF_SHARED; 729 730 ret = devm_request_threaded_irq(&i2c->dev, 731 irq, 732 ak8974_drdy_irq, 733 ak8974_drdy_irq_thread, 734 irq_trig, 735 ak8974->name, 736 ak8974); 737 if (ret) { 738 dev_err(&i2c->dev, "unable to request DRDY IRQ " 739 "- proceeding without IRQ\n"); 740 goto no_irq; 741 } 742 ak8974->drdy_irq = true; 743 } 744 745 no_irq: 746 ret = iio_device_register(indio_dev); 747 if (ret) { 748 dev_err(&i2c->dev, "device register failed\n"); 749 goto cleanup_buffer; 750 } 751 752 return 0; 753 754 cleanup_buffer: 755 iio_triggered_buffer_cleanup(indio_dev); 756 disable_pm: 757 pm_runtime_put_noidle(&i2c->dev); 758 pm_runtime_disable(&i2c->dev); 759 ak8974_set_power(ak8974, AK8974_PWR_OFF); 760 power_off: 761 regulator_bulk_disable(ARRAY_SIZE(ak8974->regs), ak8974->regs); 762 763 return ret; 764 } 765 766 static int ak8974_remove(struct i2c_client *i2c) 767 { 768 struct iio_dev *indio_dev = i2c_get_clientdata(i2c); 769 struct ak8974 *ak8974 = iio_priv(indio_dev); 770 771 iio_device_unregister(indio_dev); 772 iio_triggered_buffer_cleanup(indio_dev); 773 pm_runtime_get_sync(&i2c->dev); 774 pm_runtime_put_noidle(&i2c->dev); 775 pm_runtime_disable(&i2c->dev); 776 ak8974_set_power(ak8974, AK8974_PWR_OFF); 777 regulator_bulk_disable(ARRAY_SIZE(ak8974->regs), ak8974->regs); 778 779 return 0; 780 } 781 782 static int __maybe_unused ak8974_runtime_suspend(struct device *dev) 783 { 784 struct ak8974 *ak8974 = 785 iio_priv(i2c_get_clientdata(to_i2c_client(dev))); 786 787 ak8974_set_power(ak8974, AK8974_PWR_OFF); 788 regulator_bulk_disable(ARRAY_SIZE(ak8974->regs), ak8974->regs); 789 790 return 0; 791 } 792 793 static int __maybe_unused ak8974_runtime_resume(struct device *dev) 794 { 795 struct ak8974 *ak8974 = 796 iio_priv(i2c_get_clientdata(to_i2c_client(dev))); 797 int ret; 798 799 ret = regulator_bulk_enable(ARRAY_SIZE(ak8974->regs), ak8974->regs); 800 if (ret) 801 return ret; 802 msleep(AK8974_POWERON_DELAY); 803 ret = ak8974_set_power(ak8974, AK8974_PWR_ON); 804 if (ret) 805 goto out_regulator_disable; 806 807 ret = ak8974_configure(ak8974); 808 if (ret) 809 goto out_disable_power; 810 811 return 0; 812 813 out_disable_power: 814 ak8974_set_power(ak8974, AK8974_PWR_OFF); 815 out_regulator_disable: 816 regulator_bulk_disable(ARRAY_SIZE(ak8974->regs), ak8974->regs); 817 818 return ret; 819 } 820 821 static const struct dev_pm_ops ak8974_dev_pm_ops = { 822 SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend, 823 pm_runtime_force_resume) 824 SET_RUNTIME_PM_OPS(ak8974_runtime_suspend, 825 ak8974_runtime_resume, NULL) 826 }; 827 828 static const struct i2c_device_id ak8974_id[] = { 829 {"ami305", 0 }, 830 {"ak8974", 0 }, 831 {} 832 }; 833 MODULE_DEVICE_TABLE(i2c, ak8974_id); 834 835 static const struct of_device_id ak8974_of_match[] = { 836 { .compatible = "asahi-kasei,ak8974", }, 837 {} 838 }; 839 MODULE_DEVICE_TABLE(of, ak8974_of_match); 840 841 static struct i2c_driver ak8974_driver = { 842 .driver = { 843 .name = "ak8974", 844 .pm = &ak8974_dev_pm_ops, 845 .of_match_table = of_match_ptr(ak8974_of_match), 846 }, 847 .probe = ak8974_probe, 848 .remove = ak8974_remove, 849 .id_table = ak8974_id, 850 }; 851 module_i2c_driver(ak8974_driver); 852 853 MODULE_DESCRIPTION("AK8974 and AMI305 3-axis magnetometer driver"); 854 MODULE_AUTHOR("Samu Onkalo"); 855 MODULE_AUTHOR("Linus Walleij"); 856 MODULE_LICENSE("GPL v2"); 857