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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * Driver for the Asahi Kasei EMD Corporation AK89744 * and Aichi Steel AMI305 magnetometer chips.5 * Based on a patch from Samu Onkalo and the AK8975 IIO driver.6 *7 * Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).8 * Copyright (c) 2010 NVIDIA Corporation.9 * Copyright (C) 2016 Linaro Ltd.10 *11 * Author: Samu Onkalo <samu.p.onkalo@nokia.com>12 * Author: Linus Walleij <linus.walleij@linaro.org>13 */14#include <linux/module.h>15#include <linux/mod_devicetable.h>16#include <linux/kernel.h>17#include <linux/i2c.h>18#include <linux/interrupt.h>19#include <linux/irq.h> /* For irq_get_irq_data() */20#include <linux/completion.h>21#include <linux/err.h>22#include <linux/mutex.h>23#include <linux/delay.h>24#include <linux/bitops.h>25#include <linux/random.h>26#include <linux/regmap.h>27#include <linux/regulator/consumer.h>28#include <linux/pm_runtime.h>29 30#include <linux/iio/iio.h>31#include <linux/iio/sysfs.h>32#include <linux/iio/buffer.h>33#include <linux/iio/trigger.h>34#include <linux/iio/trigger_consumer.h>35#include <linux/iio/triggered_buffer.h>36 37/*38 * 16-bit registers are little-endian. LSB is at the address defined below39 * and MSB is at the next higher address.40 */41 42/* These registers are common for AK8974 and AMI30x */43#define AK8974_SELFTEST 0x0C44#define AK8974_SELFTEST_IDLE 0x5545#define AK8974_SELFTEST_OK 0xAA46 47#define AK8974_INFO 0x0D48 49#define AK8974_WHOAMI 0x0F50#define AK8974_WHOAMI_VALUE_AMI306 0x4651#define AK8974_WHOAMI_VALUE_AMI305 0x4752#define AK8974_WHOAMI_VALUE_AK8974 0x4853#define AK8974_WHOAMI_VALUE_HSCDTD008A 0x4954 55#define AK8974_DATA_X 0x1056#define AK8974_DATA_Y 0x1257#define AK8974_DATA_Z 0x1458#define AK8974_INT_SRC 0x1659#define AK8974_STATUS 0x1860#define AK8974_INT_CLEAR 0x1A61#define AK8974_CTRL1 0x1B62#define AK8974_CTRL2 0x1C63#define AK8974_CTRL3 0x1D64#define AK8974_INT_CTRL 0x1E65#define AK8974_INT_THRES 0x26 /* Absolute any axis value threshold */66#define AK8974_PRESET 0x3067 68/* AK8974-specific offsets */69#define AK8974_OFFSET_X 0x2070#define AK8974_OFFSET_Y 0x2271#define AK8974_OFFSET_Z 0x2472/* AMI305-specific offsets */73#define AMI305_OFFSET_X 0x6C74#define AMI305_OFFSET_Y 0x7275#define AMI305_OFFSET_Z 0x7876 77/* Different temperature registers */78#define AK8974_TEMP 0x3179#define AMI305_TEMP 0x6080 81/* AMI306-specific control register */82#define AMI306_CTRL4 0x5C83 84/* AMI306 factory calibration data */85 86/* fine axis sensitivity */87#define AMI306_FINEOUTPUT_X 0x9088#define AMI306_FINEOUTPUT_Y 0x9289#define AMI306_FINEOUTPUT_Z 0x9490 91/* axis sensitivity */92#define AMI306_SENS_X 0x9693#define AMI306_SENS_Y 0x9894#define AMI306_SENS_Z 0x9A95 96/* axis cross-interference */97#define AMI306_GAIN_PARA_XZ 0x9C98#define AMI306_GAIN_PARA_XY 0x9D99#define AMI306_GAIN_PARA_YZ 0x9E100#define AMI306_GAIN_PARA_YX 0x9F101#define AMI306_GAIN_PARA_ZY 0xA0102#define AMI306_GAIN_PARA_ZX 0xA1103 104/* offset at ZERO magnetic field */105#define AMI306_OFFZERO_X 0xF8106#define AMI306_OFFZERO_Y 0xFA107#define AMI306_OFFZERO_Z 0xFC108 109 110#define AK8974_INT_X_HIGH BIT(7) /* Axis over +threshold */111#define AK8974_INT_Y_HIGH BIT(6)112#define AK8974_INT_Z_HIGH BIT(5)113#define AK8974_INT_X_LOW BIT(4) /* Axis below -threshold */114#define AK8974_INT_Y_LOW BIT(3)115#define AK8974_INT_Z_LOW BIT(2)116#define AK8974_INT_RANGE BIT(1) /* Range overflow (any axis) */117 118#define AK8974_STATUS_DRDY BIT(6) /* Data ready */119#define AK8974_STATUS_OVERRUN BIT(5) /* Data overrun */120#define AK8974_STATUS_INT BIT(4) /* Interrupt occurred */121 122#define AK8974_CTRL1_POWER BIT(7) /* 0 = standby; 1 = active */123#define AK8974_CTRL1_RATE BIT(4) /* 0 = 10 Hz; 1 = 20 Hz */124#define AK8974_CTRL1_FORCE_EN BIT(1) /* 0 = normal; 1 = force */125#define AK8974_CTRL1_MODE2 BIT(0) /* 0 */126 127#define AK8974_CTRL2_INT_EN BIT(4) /* 1 = enable interrupts */128#define AK8974_CTRL2_DRDY_EN BIT(3) /* 1 = enable data ready signal */129#define AK8974_CTRL2_DRDY_POL BIT(2) /* 1 = data ready active high */130#define AK8974_CTRL2_RESDEF (AK8974_CTRL2_DRDY_POL)131 132#define AK8974_CTRL3_RESET BIT(7) /* Software reset */133#define AK8974_CTRL3_FORCE BIT(6) /* Start forced measurement */134#define AK8974_CTRL3_SELFTEST BIT(4) /* Set selftest register */135#define AK8974_CTRL3_RESDEF 0x00136 137#define AK8974_INT_CTRL_XEN BIT(7) /* Enable interrupt for this axis */138#define AK8974_INT_CTRL_YEN BIT(6)139#define AK8974_INT_CTRL_ZEN BIT(5)140#define AK8974_INT_CTRL_XYZEN (BIT(7)|BIT(6)|BIT(5))141#define AK8974_INT_CTRL_POL BIT(3) /* 0 = active low; 1 = active high */142#define AK8974_INT_CTRL_PULSE BIT(1) /* 0 = latched; 1 = pulse (50 usec) */143#define AK8974_INT_CTRL_RESDEF (AK8974_INT_CTRL_XYZEN | AK8974_INT_CTRL_POL)144 145/* HSCDTD008A-specific control register */146#define HSCDTD008A_CTRL4 0x1E147#define HSCDTD008A_CTRL4_MMD BIT(7) /* must be set to 1 */148#define HSCDTD008A_CTRL4_RANGE BIT(4) /* 0 = 14-bit output; 1 = 15-bit output */149#define HSCDTD008A_CTRL4_RESDEF (HSCDTD008A_CTRL4_MMD | HSCDTD008A_CTRL4_RANGE)150 151/* The AMI305 has elaborate FW version and serial number registers */152#define AMI305_VER 0xE8153#define AMI305_SN 0xEA154 155#define AK8974_MAX_RANGE 2048156 157#define AK8974_POWERON_DELAY 50158#define AK8974_ACTIVATE_DELAY 1159#define AK8974_SELFTEST_DELAY 1160/*161 * Set the autosuspend to two orders of magnitude larger than the poweron162 * delay to make sane reasonable power tradeoff savings (5 seconds in163 * this case).164 */165#define AK8974_AUTOSUSPEND_DELAY 5000166 167#define AK8974_MEASTIME 3168 169#define AK8974_PWR_ON 1170#define AK8974_PWR_OFF 0171 172/**173 * struct ak8974 - state container for the AK8974 driver174 * @i2c: parent I2C client175 * @orientation: mounting matrix, flipped axis etc176 * @map: regmap to access the AK8974 registers over I2C177 * @regs: the avdd and dvdd power regulators178 * @name: the name of the part179 * @variant: the whoami ID value (for selecting code paths)180 * @lock: locks the magnetometer for exclusive use during a measurement181 * @drdy_irq: uses the DRDY IRQ line182 * @drdy_complete: completion for DRDY183 * @drdy_active_low: the DRDY IRQ is active low184 * @scan: timestamps185 */186struct ak8974 {187 struct i2c_client *i2c;188 struct iio_mount_matrix orientation;189 struct regmap *map;190 struct regulator_bulk_data regs[2];191 const char *name;192 u8 variant;193 struct mutex lock;194 bool drdy_irq;195 struct completion drdy_complete;196 bool drdy_active_low;197 /* Ensure timestamp is naturally aligned */198 struct {199 __le16 channels[3];200 s64 ts __aligned(8);201 } scan;202};203 204static const char ak8974_reg_avdd[] = "avdd";205static const char ak8974_reg_dvdd[] = "dvdd";206 207static int ak8974_get_u16_val(struct ak8974 *ak8974, u8 reg, u16 *val)208{209 int ret;210 __le16 bulk;211 212 ret = regmap_bulk_read(ak8974->map, reg, &bulk, 2);213 if (ret)214 return ret;215 *val = le16_to_cpu(bulk);216 217 return 0;218}219 220static int ak8974_set_u16_val(struct ak8974 *ak8974, u8 reg, u16 val)221{222 __le16 bulk = cpu_to_le16(val);223 224 return regmap_bulk_write(ak8974->map, reg, &bulk, 2);225}226 227static int ak8974_set_power(struct ak8974 *ak8974, bool mode)228{229 int ret;230 u8 val;231 232 val = mode ? AK8974_CTRL1_POWER : 0;233 val |= AK8974_CTRL1_FORCE_EN;234 ret = regmap_write(ak8974->map, AK8974_CTRL1, val);235 if (ret < 0)236 return ret;237 238 if (mode)239 msleep(AK8974_ACTIVATE_DELAY);240 241 return 0;242}243 244static int ak8974_reset(struct ak8974 *ak8974)245{246 int ret;247 248 /* Power on to get register access. Sets CTRL1 reg to reset state */249 ret = ak8974_set_power(ak8974, AK8974_PWR_ON);250 if (ret)251 return ret;252 ret = regmap_write(ak8974->map, AK8974_CTRL2, AK8974_CTRL2_RESDEF);253 if (ret)254 return ret;255 ret = regmap_write(ak8974->map, AK8974_CTRL3, AK8974_CTRL3_RESDEF);256 if (ret)257 return ret;258 if (ak8974->variant != AK8974_WHOAMI_VALUE_HSCDTD008A) {259 ret = regmap_write(ak8974->map, AK8974_INT_CTRL,260 AK8974_INT_CTRL_RESDEF);261 if (ret)262 return ret;263 } else {264 ret = regmap_write(ak8974->map, HSCDTD008A_CTRL4,265 HSCDTD008A_CTRL4_RESDEF);266 if (ret)267 return ret;268 }269 270 /* After reset, power off is default state */271 return ak8974_set_power(ak8974, AK8974_PWR_OFF);272}273 274static int ak8974_configure(struct ak8974 *ak8974)275{276 int ret;277 278 ret = regmap_write(ak8974->map, AK8974_CTRL2, AK8974_CTRL2_DRDY_EN |279 AK8974_CTRL2_INT_EN);280 if (ret)281 return ret;282 ret = regmap_write(ak8974->map, AK8974_CTRL3, 0);283 if (ret)284 return ret;285 if (ak8974->variant == AK8974_WHOAMI_VALUE_AMI306) {286 /* magic from datasheet: set high-speed measurement mode */287 ret = ak8974_set_u16_val(ak8974, AMI306_CTRL4, 0xA07E);288 if (ret)289 return ret;290 }291 if (ak8974->variant == AK8974_WHOAMI_VALUE_HSCDTD008A)292 return 0;293 ret = regmap_write(ak8974->map, AK8974_INT_CTRL, AK8974_INT_CTRL_POL);294 if (ret)295 return ret;296 297 return regmap_write(ak8974->map, AK8974_PRESET, 0);298}299 300static int ak8974_trigmeas(struct ak8974 *ak8974)301{302 unsigned int clear;303 u8 mask;304 u8 val;305 int ret;306 307 /* Clear any previous measurement overflow status */308 ret = regmap_read(ak8974->map, AK8974_INT_CLEAR, &clear);309 if (ret)310 return ret;311 312 /* If we have a DRDY IRQ line, use it */313 if (ak8974->drdy_irq) {314 mask = AK8974_CTRL2_INT_EN |315 AK8974_CTRL2_DRDY_EN |316 AK8974_CTRL2_DRDY_POL;317 val = AK8974_CTRL2_DRDY_EN;318 319 if (!ak8974->drdy_active_low)320 val |= AK8974_CTRL2_DRDY_POL;321 322 init_completion(&ak8974->drdy_complete);323 ret = regmap_update_bits(ak8974->map, AK8974_CTRL2,324 mask, val);325 if (ret)326 return ret;327 }328 329 /* Force a measurement */330 return regmap_set_bits(ak8974->map, AK8974_CTRL3, AK8974_CTRL3_FORCE);331}332 333static int ak8974_await_drdy(struct ak8974 *ak8974)334{335 int timeout = 2;336 unsigned int val;337 int ret;338 339 if (ak8974->drdy_irq) {340 ret = wait_for_completion_timeout(&ak8974->drdy_complete,341 1 + msecs_to_jiffies(1000));342 if (!ret) {343 dev_err(&ak8974->i2c->dev,344 "timeout waiting for DRDY IRQ\n");345 return -ETIMEDOUT;346 }347 return 0;348 }349 350 /* Default delay-based poll loop */351 do {352 msleep(AK8974_MEASTIME);353 ret = regmap_read(ak8974->map, AK8974_STATUS, &val);354 if (ret < 0)355 return ret;356 if (val & AK8974_STATUS_DRDY)357 return 0;358 } while (--timeout);359 360 dev_err(&ak8974->i2c->dev, "timeout waiting for DRDY\n");361 return -ETIMEDOUT;362}363 364static int ak8974_getresult(struct ak8974 *ak8974, __le16 *result)365{366 unsigned int src;367 int ret;368 369 ret = ak8974_await_drdy(ak8974);370 if (ret)371 return ret;372 ret = regmap_read(ak8974->map, AK8974_INT_SRC, &src);373 if (ret < 0)374 return ret;375 376 /* Out of range overflow! Strong magnet close? */377 if (src & AK8974_INT_RANGE) {378 dev_err(&ak8974->i2c->dev,379 "range overflow in sensor\n");380 return -ERANGE;381 }382 383 ret = regmap_bulk_read(ak8974->map, AK8974_DATA_X, result, 6);384 if (ret)385 return ret;386 387 return ret;388}389 390static irqreturn_t ak8974_drdy_irq(int irq, void *d)391{392 struct ak8974 *ak8974 = d;393 394 if (!ak8974->drdy_irq)395 return IRQ_NONE;396 397 /* TODO: timestamp here to get good measurement stamps */398 return IRQ_WAKE_THREAD;399}400 401static irqreturn_t ak8974_drdy_irq_thread(int irq, void *d)402{403 struct ak8974 *ak8974 = d;404 unsigned int val;405 int ret;406 407 /* Check if this was a DRDY from us */408 ret = regmap_read(ak8974->map, AK8974_STATUS, &val);409 if (ret < 0) {410 dev_err(&ak8974->i2c->dev, "error reading DRDY status\n");411 return IRQ_HANDLED;412 }413 if (val & AK8974_STATUS_DRDY) {414 /* Yes this was our IRQ */415 complete(&ak8974->drdy_complete);416 return IRQ_HANDLED;417 }418 419 /* We may be on a shared IRQ, let the next client check */420 return IRQ_NONE;421}422 423static int ak8974_selftest(struct ak8974 *ak8974)424{425 struct device *dev = &ak8974->i2c->dev;426 unsigned int val;427 int ret;428 429 ret = regmap_read(ak8974->map, AK8974_SELFTEST, &val);430 if (ret)431 return ret;432 if (val != AK8974_SELFTEST_IDLE) {433 dev_err(dev, "selftest not idle before test\n");434 return -EIO;435 }436 437 /* Trigger self-test */438 ret = regmap_set_bits(ak8974->map, AK8974_CTRL3, AK8974_CTRL3_SELFTEST);439 if (ret) {440 dev_err(dev, "could not write CTRL3\n");441 return ret;442 }443 444 msleep(AK8974_SELFTEST_DELAY);445 446 ret = regmap_read(ak8974->map, AK8974_SELFTEST, &val);447 if (ret)448 return ret;449 if (val != AK8974_SELFTEST_OK) {450 dev_err(dev, "selftest result NOT OK (%02x)\n", val);451 return -EIO;452 }453 454 ret = regmap_read(ak8974->map, AK8974_SELFTEST, &val);455 if (ret)456 return ret;457 if (val != AK8974_SELFTEST_IDLE) {458 dev_err(dev, "selftest not idle after test (%02x)\n", val);459 return -EIO;460 }461 dev_dbg(dev, "passed self-test\n");462 463 return 0;464}465 466static void ak8974_read_calib_data(struct ak8974 *ak8974, unsigned int reg,467 __le16 *tab, size_t tab_size)468{469 int ret = regmap_bulk_read(ak8974->map, reg, tab, tab_size);470 if (ret) {471 memset(tab, 0xFF, tab_size);472 dev_warn(&ak8974->i2c->dev,473 "can't read calibration data (regs %u..%zu): %d\n",474 reg, reg + tab_size - 1, ret);475 } else {476 add_device_randomness(tab, tab_size);477 }478}479 480static int ak8974_detect(struct ak8974 *ak8974)481{482 unsigned int whoami;483 const char *name;484 int ret;485 unsigned int fw;486 u16 sn;487 488 ret = regmap_read(ak8974->map, AK8974_WHOAMI, &whoami);489 if (ret)490 return ret;491 492 name = "ami305";493 494 switch (whoami) {495 case AK8974_WHOAMI_VALUE_AMI306:496 name = "ami306";497 fallthrough;498 case AK8974_WHOAMI_VALUE_AMI305:499 ret = regmap_read(ak8974->map, AMI305_VER, &fw);500 if (ret)501 return ret;502 fw &= 0x7f; /* only bits 0 thru 6 valid */503 ret = ak8974_get_u16_val(ak8974, AMI305_SN, &sn);504 if (ret)505 return ret;506 add_device_randomness(&sn, sizeof(sn));507 dev_info(&ak8974->i2c->dev,508 "detected %s, FW ver %02x, S/N: %04x\n",509 name, fw, sn);510 break;511 case AK8974_WHOAMI_VALUE_AK8974:512 name = "ak8974";513 dev_info(&ak8974->i2c->dev, "detected AK8974\n");514 break;515 case AK8974_WHOAMI_VALUE_HSCDTD008A:516 name = "hscdtd008a";517 dev_info(&ak8974->i2c->dev, "detected hscdtd008a\n");518 break;519 default:520 dev_err(&ak8974->i2c->dev, "unsupported device (%02x) ",521 whoami);522 return -ENODEV;523 }524 525 ak8974->name = name;526 ak8974->variant = whoami;527 528 if (whoami == AK8974_WHOAMI_VALUE_AMI306) {529 __le16 fab_data1[9], fab_data2[3];530 int i;531 532 ak8974_read_calib_data(ak8974, AMI306_FINEOUTPUT_X,533 fab_data1, sizeof(fab_data1));534 ak8974_read_calib_data(ak8974, AMI306_OFFZERO_X,535 fab_data2, sizeof(fab_data2));536 537 for (i = 0; i < 3; ++i) {538 static const char axis[3] = "XYZ";539 static const char pgaxis[6] = "ZYZXYX";540 unsigned offz = le16_to_cpu(fab_data2[i]) & 0x7F;541 unsigned fine = le16_to_cpu(fab_data1[i]);542 unsigned sens = le16_to_cpu(fab_data1[i + 3]);543 unsigned pgain1 = le16_to_cpu(fab_data1[i + 6]);544 unsigned pgain2 = pgain1 >> 8;545 546 pgain1 &= 0xFF;547 548 dev_info(&ak8974->i2c->dev,549 "factory calibration for axis %c: offz=%u sens=%u fine=%u pga%c=%u pga%c=%u\n",550 axis[i], offz, sens, fine, pgaxis[i * 2],551 pgain1, pgaxis[i * 2 + 1], pgain2);552 }553 }554 555 return 0;556}557 558static int ak8974_measure_channel(struct ak8974 *ak8974, unsigned long address,559 int *val)560{561 __le16 hw_values[3];562 int ret;563 564 pm_runtime_get_sync(&ak8974->i2c->dev);565 mutex_lock(&ak8974->lock);566 567 /*568 * We read all axes and discard all but one, for optimized569 * reading, use the triggered buffer.570 */571 ret = ak8974_trigmeas(ak8974);572 if (ret)573 goto out_unlock;574 ret = ak8974_getresult(ak8974, hw_values);575 if (ret)576 goto out_unlock;577 /*578 * This explicit cast to (s16) is necessary as the measurement579 * is done in 2's complement with positive and negative values.580 * The follwing assignment to *val will then convert the signed581 * s16 value to a signed int value.582 */583 *val = (s16)le16_to_cpu(hw_values[address]);584out_unlock:585 mutex_unlock(&ak8974->lock);586 pm_runtime_mark_last_busy(&ak8974->i2c->dev);587 pm_runtime_put_autosuspend(&ak8974->i2c->dev);588 589 return ret;590}591 592static int ak8974_read_raw(struct iio_dev *indio_dev,593 struct iio_chan_spec const *chan,594 int *val, int *val2,595 long mask)596{597 struct ak8974 *ak8974 = iio_priv(indio_dev);598 int ret;599 600 switch (mask) {601 case IIO_CHAN_INFO_RAW:602 if (chan->address > 2) {603 dev_err(&ak8974->i2c->dev, "faulty channel address\n");604 return -EIO;605 }606 ret = ak8974_measure_channel(ak8974, chan->address, val);607 if (ret)608 return ret;609 return IIO_VAL_INT;610 case IIO_CHAN_INFO_SCALE:611 switch (ak8974->variant) {612 case AK8974_WHOAMI_VALUE_AMI306:613 case AK8974_WHOAMI_VALUE_AMI305:614 /*615 * The datasheet for AMI305 and AMI306, page 6616 * specifies the range of the sensor to be617 * +/- 12 Gauss.618 */619 *val = 12;620 /*621 * 12 bits are used, +/- 2^11622 * [ -2048 .. 2047 ] (manual page 20)623 * [ 0xf800 .. 0x07ff ]624 */625 *val2 = 11;626 return IIO_VAL_FRACTIONAL_LOG2;627 case AK8974_WHOAMI_VALUE_HSCDTD008A:628 /*629 * The datasheet for HSCDTF008A, page 3 specifies the630 * range of the sensor as +/- 2.4 mT per axis, which631 * corresponds to +/- 2400 uT = +/- 24 Gauss.632 */633 *val = 24;634 /*635 * 15 bits are used (set up in CTRL4), +/- 2^14636 * [ -16384 .. 16383 ] (manual page 24)637 * [ 0xc000 .. 0x3fff ]638 */639 *val2 = 14;640 return IIO_VAL_FRACTIONAL_LOG2;641 default:642 /* GUESSING +/- 12 Gauss */643 *val = 12;644 /* GUESSING 12 bits ADC +/- 2^11 */645 *val2 = 11;646 return IIO_VAL_FRACTIONAL_LOG2;647 }648 break;649 default:650 /* Unknown request */651 break;652 }653 654 return -EINVAL;655}656 657static void ak8974_fill_buffer(struct iio_dev *indio_dev)658{659 struct ak8974 *ak8974 = iio_priv(indio_dev);660 int ret;661 662 pm_runtime_get_sync(&ak8974->i2c->dev);663 mutex_lock(&ak8974->lock);664 665 ret = ak8974_trigmeas(ak8974);666 if (ret) {667 dev_err(&ak8974->i2c->dev, "error triggering measure\n");668 goto out_unlock;669 }670 ret = ak8974_getresult(ak8974, ak8974->scan.channels);671 if (ret) {672 dev_err(&ak8974->i2c->dev, "error getting measures\n");673 goto out_unlock;674 }675 676 iio_push_to_buffers_with_timestamp(indio_dev, &ak8974->scan,677 iio_get_time_ns(indio_dev));678 679 out_unlock:680 mutex_unlock(&ak8974->lock);681 pm_runtime_mark_last_busy(&ak8974->i2c->dev);682 pm_runtime_put_autosuspend(&ak8974->i2c->dev);683}684 685static irqreturn_t ak8974_handle_trigger(int irq, void *p)686{687 const struct iio_poll_func *pf = p;688 struct iio_dev *indio_dev = pf->indio_dev;689 690 ak8974_fill_buffer(indio_dev);691 iio_trigger_notify_done(indio_dev->trig);692 693 return IRQ_HANDLED;694}695 696static const struct iio_mount_matrix *697ak8974_get_mount_matrix(const struct iio_dev *indio_dev,698 const struct iio_chan_spec *chan)699{700 struct ak8974 *ak8974 = iio_priv(indio_dev);701 702 return &ak8974->orientation;703}704 705static const struct iio_chan_spec_ext_info ak8974_ext_info[] = {706 IIO_MOUNT_MATRIX(IIO_SHARED_BY_DIR, ak8974_get_mount_matrix),707 { },708};709 710#define AK8974_AXIS_CHANNEL(axis, index, bits) \711 { \712 .type = IIO_MAGN, \713 .modified = 1, \714 .channel2 = IIO_MOD_##axis, \715 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \716 BIT(IIO_CHAN_INFO_SCALE), \717 .ext_info = ak8974_ext_info, \718 .address = index, \719 .scan_index = index, \720 .scan_type = { \721 .sign = 's', \722 .realbits = bits, \723 .storagebits = 16, \724 .endianness = IIO_LE \725 }, \726 }727 728/*729 * We have no datasheet for the AK8974 but we guess that its730 * ADC is 12 bits. The AMI305 and AMI306 certainly has 12bit731 * ADC.732 */733static const struct iio_chan_spec ak8974_12_bits_channels[] = {734 AK8974_AXIS_CHANNEL(X, 0, 12),735 AK8974_AXIS_CHANNEL(Y, 1, 12),736 AK8974_AXIS_CHANNEL(Z, 2, 12),737 IIO_CHAN_SOFT_TIMESTAMP(3),738};739 740/*741 * The HSCDTD008A has 15 bits resolution the way we set it up742 * in CTRL4.743 */744static const struct iio_chan_spec ak8974_15_bits_channels[] = {745 AK8974_AXIS_CHANNEL(X, 0, 15),746 AK8974_AXIS_CHANNEL(Y, 1, 15),747 AK8974_AXIS_CHANNEL(Z, 2, 15),748 IIO_CHAN_SOFT_TIMESTAMP(3),749};750 751static const unsigned long ak8974_scan_masks[] = { 0x7, 0 };752 753static const struct iio_info ak8974_info = {754 .read_raw = &ak8974_read_raw,755};756 757static bool ak8974_writeable_reg(struct device *dev, unsigned int reg)758{759 struct i2c_client *i2c = to_i2c_client(dev);760 struct iio_dev *indio_dev = i2c_get_clientdata(i2c);761 struct ak8974 *ak8974 = iio_priv(indio_dev);762 763 switch (reg) {764 case AK8974_CTRL1:765 case AK8974_CTRL2:766 case AK8974_CTRL3:767 case AK8974_INT_CTRL:768 case AK8974_INT_THRES:769 case AK8974_INT_THRES + 1:770 return true;771 case AK8974_PRESET:772 case AK8974_PRESET + 1:773 return ak8974->variant != AK8974_WHOAMI_VALUE_HSCDTD008A;774 case AK8974_OFFSET_X:775 case AK8974_OFFSET_X + 1:776 case AK8974_OFFSET_Y:777 case AK8974_OFFSET_Y + 1:778 case AK8974_OFFSET_Z:779 case AK8974_OFFSET_Z + 1:780 return ak8974->variant == AK8974_WHOAMI_VALUE_AK8974 ||781 ak8974->variant == AK8974_WHOAMI_VALUE_HSCDTD008A;782 case AMI305_OFFSET_X:783 case AMI305_OFFSET_X + 1:784 case AMI305_OFFSET_Y:785 case AMI305_OFFSET_Y + 1:786 case AMI305_OFFSET_Z:787 case AMI305_OFFSET_Z + 1:788 return ak8974->variant == AK8974_WHOAMI_VALUE_AMI305 ||789 ak8974->variant == AK8974_WHOAMI_VALUE_AMI306;790 case AMI306_CTRL4:791 case AMI306_CTRL4 + 1:792 return ak8974->variant == AK8974_WHOAMI_VALUE_AMI306;793 default:794 return false;795 }796}797 798static bool ak8974_precious_reg(struct device *dev, unsigned int reg)799{800 return reg == AK8974_INT_CLEAR;801}802 803static const struct regmap_config ak8974_regmap_config = {804 .reg_bits = 8,805 .val_bits = 8,806 .max_register = 0xff,807 .writeable_reg = ak8974_writeable_reg,808 .precious_reg = ak8974_precious_reg,809};810 811static int ak8974_probe(struct i2c_client *i2c)812{813 struct iio_dev *indio_dev;814 struct ak8974 *ak8974;815 unsigned long irq_trig;816 int irq = i2c->irq;817 int ret;818 819 /* Register with IIO */820 indio_dev = devm_iio_device_alloc(&i2c->dev, sizeof(*ak8974));821 if (indio_dev == NULL)822 return -ENOMEM;823 824 ak8974 = iio_priv(indio_dev);825 i2c_set_clientdata(i2c, indio_dev);826 ak8974->i2c = i2c;827 mutex_init(&ak8974->lock);828 829 ret = iio_read_mount_matrix(&i2c->dev, &ak8974->orientation);830 if (ret)831 return ret;832 833 ak8974->regs[0].supply = ak8974_reg_avdd;834 ak8974->regs[1].supply = ak8974_reg_dvdd;835 836 ret = devm_regulator_bulk_get(&i2c->dev,837 ARRAY_SIZE(ak8974->regs),838 ak8974->regs);839 if (ret < 0)840 return dev_err_probe(&i2c->dev, ret, "cannot get regulators\n");841 842 ret = regulator_bulk_enable(ARRAY_SIZE(ak8974->regs), ak8974->regs);843 if (ret < 0) {844 dev_err(&i2c->dev, "cannot enable regulators\n");845 return ret;846 }847 848 /* Take runtime PM online */849 pm_runtime_get_noresume(&i2c->dev);850 pm_runtime_set_active(&i2c->dev);851 pm_runtime_enable(&i2c->dev);852 853 ak8974->map = devm_regmap_init_i2c(i2c, &ak8974_regmap_config);854 if (IS_ERR(ak8974->map)) {855 dev_err(&i2c->dev, "failed to allocate register map\n");856 pm_runtime_put_noidle(&i2c->dev);857 pm_runtime_disable(&i2c->dev);858 return PTR_ERR(ak8974->map);859 }860 861 ret = ak8974_set_power(ak8974, AK8974_PWR_ON);862 if (ret) {863 dev_err(&i2c->dev, "could not power on\n");864 goto disable_pm;865 }866 867 ret = ak8974_detect(ak8974);868 if (ret) {869 dev_err(&i2c->dev, "neither AK8974 nor AMI30x found\n");870 goto disable_pm;871 }872 873 ret = ak8974_selftest(ak8974);874 if (ret)875 dev_err(&i2c->dev, "selftest failed (continuing anyway)\n");876 877 ret = ak8974_reset(ak8974);878 if (ret) {879 dev_err(&i2c->dev, "AK8974 reset failed\n");880 goto disable_pm;881 }882 883 switch (ak8974->variant) {884 case AK8974_WHOAMI_VALUE_AMI306:885 case AK8974_WHOAMI_VALUE_AMI305:886 indio_dev->channels = ak8974_12_bits_channels;887 indio_dev->num_channels = ARRAY_SIZE(ak8974_12_bits_channels);888 break;889 case AK8974_WHOAMI_VALUE_HSCDTD008A:890 indio_dev->channels = ak8974_15_bits_channels;891 indio_dev->num_channels = ARRAY_SIZE(ak8974_15_bits_channels);892 break;893 default:894 indio_dev->channels = ak8974_12_bits_channels;895 indio_dev->num_channels = ARRAY_SIZE(ak8974_12_bits_channels);896 break;897 }898 indio_dev->info = &ak8974_info;899 indio_dev->available_scan_masks = ak8974_scan_masks;900 indio_dev->modes = INDIO_DIRECT_MODE;901 indio_dev->name = ak8974->name;902 903 ret = iio_triggered_buffer_setup(indio_dev, NULL,904 ak8974_handle_trigger,905 NULL);906 if (ret) {907 dev_err(&i2c->dev, "triggered buffer setup failed\n");908 goto disable_pm;909 }910 911 /* If we have a valid DRDY IRQ, make use of it */912 if (irq > 0) {913 irq_trig = irqd_get_trigger_type(irq_get_irq_data(irq));914 if (irq_trig == IRQF_TRIGGER_RISING) {915 dev_info(&i2c->dev, "enable rising edge DRDY IRQ\n");916 } else if (irq_trig == IRQF_TRIGGER_FALLING) {917 ak8974->drdy_active_low = true;918 dev_info(&i2c->dev, "enable falling edge DRDY IRQ\n");919 } else {920 irq_trig = IRQF_TRIGGER_RISING;921 }922 irq_trig |= IRQF_ONESHOT;923 irq_trig |= IRQF_SHARED;924 925 ret = devm_request_threaded_irq(&i2c->dev,926 irq,927 ak8974_drdy_irq,928 ak8974_drdy_irq_thread,929 irq_trig,930 ak8974->name,931 ak8974);932 if (ret) {933 dev_err(&i2c->dev, "unable to request DRDY IRQ "934 "- proceeding without IRQ\n");935 goto no_irq;936 }937 ak8974->drdy_irq = true;938 }939 940no_irq:941 ret = iio_device_register(indio_dev);942 if (ret) {943 dev_err(&i2c->dev, "device register failed\n");944 goto cleanup_buffer;945 }946 947 pm_runtime_set_autosuspend_delay(&i2c->dev,948 AK8974_AUTOSUSPEND_DELAY);949 pm_runtime_use_autosuspend(&i2c->dev);950 pm_runtime_put(&i2c->dev);951 952 return 0;953 954cleanup_buffer:955 iio_triggered_buffer_cleanup(indio_dev);956disable_pm:957 pm_runtime_put_noidle(&i2c->dev);958 pm_runtime_disable(&i2c->dev);959 ak8974_set_power(ak8974, AK8974_PWR_OFF);960 regulator_bulk_disable(ARRAY_SIZE(ak8974->regs), ak8974->regs);961 962 return ret;963}964 965static void ak8974_remove(struct i2c_client *i2c)966{967 struct iio_dev *indio_dev = i2c_get_clientdata(i2c);968 struct ak8974 *ak8974 = iio_priv(indio_dev);969 970 iio_device_unregister(indio_dev);971 iio_triggered_buffer_cleanup(indio_dev);972 pm_runtime_get_sync(&i2c->dev);973 pm_runtime_put_noidle(&i2c->dev);974 pm_runtime_disable(&i2c->dev);975 ak8974_set_power(ak8974, AK8974_PWR_OFF);976 regulator_bulk_disable(ARRAY_SIZE(ak8974->regs), ak8974->regs);977}978 979static int ak8974_runtime_suspend(struct device *dev)980{981 struct ak8974 *ak8974 =982 iio_priv(i2c_get_clientdata(to_i2c_client(dev)));983 984 ak8974_set_power(ak8974, AK8974_PWR_OFF);985 regulator_bulk_disable(ARRAY_SIZE(ak8974->regs), ak8974->regs);986 987 return 0;988}989 990static int ak8974_runtime_resume(struct device *dev)991{992 struct ak8974 *ak8974 =993 iio_priv(i2c_get_clientdata(to_i2c_client(dev)));994 int ret;995 996 ret = regulator_bulk_enable(ARRAY_SIZE(ak8974->regs), ak8974->regs);997 if (ret)998 return ret;999 msleep(AK8974_POWERON_DELAY);1000 ret = ak8974_set_power(ak8974, AK8974_PWR_ON);1001 if (ret)1002 goto out_regulator_disable;1003 1004 ret = ak8974_configure(ak8974);1005 if (ret)1006 goto out_disable_power;1007 1008 return 0;1009 1010out_disable_power:1011 ak8974_set_power(ak8974, AK8974_PWR_OFF);1012out_regulator_disable:1013 regulator_bulk_disable(ARRAY_SIZE(ak8974->regs), ak8974->regs);1014 1015 return ret;1016}1017 1018static DEFINE_RUNTIME_DEV_PM_OPS(ak8974_dev_pm_ops, ak8974_runtime_suspend,1019 ak8974_runtime_resume, NULL);1020 1021static const struct i2c_device_id ak8974_id[] = {1022 { "ami305" },1023 { "ami306" },1024 { "ak8974" },1025 { "hscdtd008a" },1026 {}1027};1028MODULE_DEVICE_TABLE(i2c, ak8974_id);1029 1030static const struct of_device_id ak8974_of_match[] = {1031 { .compatible = "asahi-kasei,ak8974", },1032 { .compatible = "alps,hscdtd008a", },1033 {}1034};1035MODULE_DEVICE_TABLE(of, ak8974_of_match);1036 1037static struct i2c_driver ak8974_driver = {1038 .driver = {1039 .name = "ak8974",1040 .pm = pm_ptr(&ak8974_dev_pm_ops),1041 .of_match_table = ak8974_of_match,1042 },1043 .probe = ak8974_probe,1044 .remove = ak8974_remove,1045 .id_table = ak8974_id,1046};1047module_i2c_driver(ak8974_driver);1048 1049MODULE_DESCRIPTION("AK8974 and AMI30x 3-axis magnetometer driver");1050MODULE_AUTHOR("Samu Onkalo");1051MODULE_AUTHOR("Linus Walleij");1052MODULE_LICENSE("GPL v2");1053