1// SPDX-License-Identifier: GPL-2.0-or-later 2/* 3 * A sensor driver for the magnetometer AK8975. 4 * 5 * Magnetic compass sensor driver for monitoring magnetic flux information. 6 * 7 * Copyright (c) 2010, NVIDIA Corporation. 8 */ 9 10#include <linux/module.h> 11#include <linux/mod_devicetable.h> 12#include <linux/kernel.h> 13#include <linux/slab.h> 14#include <linux/i2c.h> 15#include <linux/interrupt.h> 16#include <linux/err.h> 17#include <linux/mutex.h> 18#include <linux/delay.h> 19#include <linux/bitops.h> 20#include <linux/gpio/consumer.h> 21#include <linux/regulator/consumer.h> 22#include <linux/pm_runtime.h> 23 24#include <linux/iio/iio.h> 25#include <linux/iio/sysfs.h> 26#include <linux/iio/buffer.h> 27#include <linux/iio/trigger.h> 28#include <linux/iio/trigger_consumer.h> 29#include <linux/iio/triggered_buffer.h> 30 31/* 32 * Register definitions, as well as various shifts and masks to get at the 33 * individual fields of the registers. 34 */ 35#define AK8975_REG_WIA 0x00 36#define AK8975_DEVICE_ID 0x48 37 38#define AK8975_REG_INFO 0x01 39 40#define AK8975_REG_ST1 0x02 41#define AK8975_REG_ST1_DRDY_SHIFT 0 42#define AK8975_REG_ST1_DRDY_MASK (1 << AK8975_REG_ST1_DRDY_SHIFT) 43 44#define AK8975_REG_HXL 0x03 45#define AK8975_REG_HXH 0x04 46#define AK8975_REG_HYL 0x05 47#define AK8975_REG_HYH 0x06 48#define AK8975_REG_HZL 0x07 49#define AK8975_REG_HZH 0x08 50#define AK8975_REG_ST2 0x09 51#define AK8975_REG_ST2_DERR_SHIFT 2 52#define AK8975_REG_ST2_DERR_MASK (1 << AK8975_REG_ST2_DERR_SHIFT) 53 54#define AK8975_REG_ST2_HOFL_SHIFT 3 55#define AK8975_REG_ST2_HOFL_MASK (1 << AK8975_REG_ST2_HOFL_SHIFT) 56 57#define AK8975_REG_CNTL 0x0A 58#define AK8975_REG_CNTL_MODE_SHIFT 0 59#define AK8975_REG_CNTL_MODE_MASK (0xF << AK8975_REG_CNTL_MODE_SHIFT) 60#define AK8975_REG_CNTL_MODE_POWER_DOWN 0x00 61#define AK8975_REG_CNTL_MODE_ONCE 0x01 62#define AK8975_REG_CNTL_MODE_SELF_TEST 0x08 63#define AK8975_REG_CNTL_MODE_FUSE_ROM 0x0F 64 65#define AK8975_REG_RSVC 0x0B 66#define AK8975_REG_ASTC 0x0C 67#define AK8975_REG_TS1 0x0D 68#define AK8975_REG_TS2 0x0E 69#define AK8975_REG_I2CDIS 0x0F 70#define AK8975_REG_ASAX 0x10 71#define AK8975_REG_ASAY 0x11 72#define AK8975_REG_ASAZ 0x12 73 74#define AK8975_MAX_REGS AK8975_REG_ASAZ 75 76/* 77 * AK09912 Register definitions 78 */ 79#define AK09912_REG_WIA1 0x00 80#define AK09912_REG_WIA2 0x01 81#define AK09912_DEVICE_ID 0x04 82#define AK09911_DEVICE_ID 0x05 83 84#define AK09911_REG_INFO1 0x02 85#define AK09911_REG_INFO2 0x03 86 87#define AK09912_REG_ST1 0x10 88 89#define AK09912_REG_ST1_DRDY_SHIFT 0 90#define AK09912_REG_ST1_DRDY_MASK (1 << AK09912_REG_ST1_DRDY_SHIFT) 91 92#define AK09912_REG_HXL 0x11 93#define AK09912_REG_HXH 0x12 94#define AK09912_REG_HYL 0x13 95#define AK09912_REG_HYH 0x14 96#define AK09912_REG_HZL 0x15 97#define AK09912_REG_HZH 0x16 98#define AK09912_REG_TMPS 0x17 99 100#define AK09912_REG_ST2 0x18 101#define AK09912_REG_ST2_HOFL_SHIFT 3 102#define AK09912_REG_ST2_HOFL_MASK (1 << AK09912_REG_ST2_HOFL_SHIFT) 103 104#define AK09912_REG_CNTL1 0x30 105 106#define AK09912_REG_CNTL2 0x31 107#define AK09912_REG_CNTL_MODE_POWER_DOWN 0x00 108#define AK09912_REG_CNTL_MODE_ONCE 0x01 109#define AK09912_REG_CNTL_MODE_SELF_TEST 0x10 110#define AK09912_REG_CNTL_MODE_FUSE_ROM 0x1F 111#define AK09912_REG_CNTL2_MODE_SHIFT 0 112#define AK09912_REG_CNTL2_MODE_MASK (0x1F << AK09912_REG_CNTL2_MODE_SHIFT) 113 114#define AK09912_REG_CNTL3 0x32 115 116#define AK09912_REG_TS1 0x33 117#define AK09912_REG_TS2 0x34 118#define AK09912_REG_TS3 0x35 119#define AK09912_REG_I2CDIS 0x36 120#define AK09912_REG_TS4 0x37 121 122#define AK09912_REG_ASAX 0x60 123#define AK09912_REG_ASAY 0x61 124#define AK09912_REG_ASAZ 0x62 125 126#define AK09912_MAX_REGS AK09912_REG_ASAZ 127 128/* 129 * Miscellaneous values. 130 */ 131#define AK8975_MAX_CONVERSION_TIMEOUT 500 132#define AK8975_CONVERSION_DONE_POLL_TIME 10 133#define AK8975_DATA_READY_TIMEOUT ((100*HZ)/1000) 134 135/* 136 * Precalculate scale factor (in Gauss units) for each axis and 137 * store in the device data. 138 * 139 * This scale factor is axis-dependent, and is derived from 3 calibration 140 * factors ASA(x), ASA(y), and ASA(z). 141 * 142 * These ASA values are read from the sensor device at start of day, and 143 * cached in the device context struct. 144 * 145 * Adjusting the flux value with the sensitivity adjustment value should be 146 * done via the following formula: 147 * 148 * Hadj = H * ( ( ( (ASA-128)*0.5 ) / 128 ) + 1 ) 149 * where H is the raw value, ASA is the sensitivity adjustment, and Hadj 150 * is the resultant adjusted value. 151 * 152 * We reduce the formula to: 153 * 154 * Hadj = H * (ASA + 128) / 256 155 * 156 * H is in the range of -4096 to 4095. The magnetometer has a range of 157 * +-1229uT. To go from the raw value to uT is: 158 * 159 * HuT = H * 1229/4096, or roughly, 3/10. 160 * 161 * Since 1uT = 0.01 gauss, our final scale factor becomes: 162 * 163 * Hadj = H * ((ASA + 128) / 256) * 3/10 * 1/100 164 * Hadj = H * ((ASA + 128) * 0.003) / 256 165 * 166 * Since ASA doesn't change, we cache the resultant scale factor into the 167 * device context in ak8975_setup(). 168 * 169 * Given we use IIO_VAL_INT_PLUS_MICRO bit when displaying the scale, we 170 * multiply the stored scale value by 1e6. 171 */ 172static long ak8975_raw_to_gauss(u16 data) 173{ 174 return (((long)data + 128) * 3000) / 256; 175} 176 177/* 178 * For AK8963 and AK09911, same calculation, but the device is less sensitive: 179 * 180 * H is in the range of +-8190. The magnetometer has a range of 181 * +-4912uT. To go from the raw value to uT is: 182 * 183 * HuT = H * 4912/8190, or roughly, 6/10, instead of 3/10. 184 */ 185 186static long ak8963_09911_raw_to_gauss(u16 data) 187{ 188 return (((long)data + 128) * 6000) / 256; 189} 190 191/* 192 * For AK09912, same calculation, except the device is more sensitive: 193 * 194 * H is in the range of -32752 to 32752. The magnetometer has a range of 195 * +-4912uT. To go from the raw value to uT is: 196 * 197 * HuT = H * 4912/32752, or roughly, 3/20, instead of 3/10. 198 */ 199static long ak09912_raw_to_gauss(u16 data) 200{ 201 return (((long)data + 128) * 1500) / 256; 202} 203 204/* Compatible Asahi Kasei Compass parts */ 205enum asahi_compass_chipset { 206 AKXXXX = 0, 207 AK8975, 208 AK8963, 209 AK09911, 210 AK09912, 211}; 212 213enum ak_ctrl_reg_addr { 214 ST1, 215 ST2, 216 CNTL, 217 ASA_BASE, 218 MAX_REGS, 219 REGS_END, 220}; 221 222enum ak_ctrl_reg_mask { 223 ST1_DRDY, 224 ST2_HOFL, 225 ST2_DERR, 226 CNTL_MODE, 227 MASK_END, 228}; 229 230enum ak_ctrl_mode { 231 POWER_DOWN, 232 MODE_ONCE, 233 SELF_TEST, 234 FUSE_ROM, 235 MODE_END, 236}; 237 238struct ak_def { 239 enum asahi_compass_chipset type; 240 long (*raw_to_gauss)(u16 data); 241 u16 range; 242 u8 ctrl_regs[REGS_END]; 243 u8 ctrl_masks[MASK_END]; 244 u8 ctrl_modes[MODE_END]; 245 u8 data_regs[3]; 246}; 247 248static const struct ak_def ak_def_array[] = { 249 { 250 .type = AK8975, 251 .raw_to_gauss = ak8975_raw_to_gauss, 252 .range = 4096, 253 .ctrl_regs = { 254 AK8975_REG_ST1, 255 AK8975_REG_ST2, 256 AK8975_REG_CNTL, 257 AK8975_REG_ASAX, 258 AK8975_MAX_REGS}, 259 .ctrl_masks = { 260 AK8975_REG_ST1_DRDY_MASK, 261 AK8975_REG_ST2_HOFL_MASK, 262 AK8975_REG_ST2_DERR_MASK, 263 AK8975_REG_CNTL_MODE_MASK}, 264 .ctrl_modes = { 265 AK8975_REG_CNTL_MODE_POWER_DOWN, 266 AK8975_REG_CNTL_MODE_ONCE, 267 AK8975_REG_CNTL_MODE_SELF_TEST, 268 AK8975_REG_CNTL_MODE_FUSE_ROM}, 269 .data_regs = { 270 AK8975_REG_HXL, 271 AK8975_REG_HYL, 272 AK8975_REG_HZL}, 273 }, 274 { 275 .type = AK8963, 276 .raw_to_gauss = ak8963_09911_raw_to_gauss, 277 .range = 8190, 278 .ctrl_regs = { 279 AK8975_REG_ST1, 280 AK8975_REG_ST2, 281 AK8975_REG_CNTL, 282 AK8975_REG_ASAX, 283 AK8975_MAX_REGS}, 284 .ctrl_masks = { 285 AK8975_REG_ST1_DRDY_MASK, 286 AK8975_REG_ST2_HOFL_MASK, 287 0, 288 AK8975_REG_CNTL_MODE_MASK}, 289 .ctrl_modes = { 290 AK8975_REG_CNTL_MODE_POWER_DOWN, 291 AK8975_REG_CNTL_MODE_ONCE, 292 AK8975_REG_CNTL_MODE_SELF_TEST, 293 AK8975_REG_CNTL_MODE_FUSE_ROM}, 294 .data_regs = { 295 AK8975_REG_HXL, 296 AK8975_REG_HYL, 297 AK8975_REG_HZL}, 298 }, 299 { 300 .type = AK09911, 301 .raw_to_gauss = ak8963_09911_raw_to_gauss, 302 .range = 8192, 303 .ctrl_regs = { 304 AK09912_REG_ST1, 305 AK09912_REG_ST2, 306 AK09912_REG_CNTL2, 307 AK09912_REG_ASAX, 308 AK09912_MAX_REGS}, 309 .ctrl_masks = { 310 AK09912_REG_ST1_DRDY_MASK, 311 AK09912_REG_ST2_HOFL_MASK, 312 0, 313 AK09912_REG_CNTL2_MODE_MASK}, 314 .ctrl_modes = { 315 AK09912_REG_CNTL_MODE_POWER_DOWN, 316 AK09912_REG_CNTL_MODE_ONCE, 317 AK09912_REG_CNTL_MODE_SELF_TEST, 318 AK09912_REG_CNTL_MODE_FUSE_ROM}, 319 .data_regs = { 320 AK09912_REG_HXL, 321 AK09912_REG_HYL, 322 AK09912_REG_HZL}, 323 }, 324 { 325 .type = AK09912, 326 .raw_to_gauss = ak09912_raw_to_gauss, 327 .range = 32752, 328 .ctrl_regs = { 329 AK09912_REG_ST1, 330 AK09912_REG_ST2, 331 AK09912_REG_CNTL2, 332 AK09912_REG_ASAX, 333 AK09912_MAX_REGS}, 334 .ctrl_masks = { 335 AK09912_REG_ST1_DRDY_MASK, 336 AK09912_REG_ST2_HOFL_MASK, 337 0, 338 AK09912_REG_CNTL2_MODE_MASK}, 339 .ctrl_modes = { 340 AK09912_REG_CNTL_MODE_POWER_DOWN, 341 AK09912_REG_CNTL_MODE_ONCE, 342 AK09912_REG_CNTL_MODE_SELF_TEST, 343 AK09912_REG_CNTL_MODE_FUSE_ROM}, 344 .data_regs = { 345 AK09912_REG_HXL, 346 AK09912_REG_HYL, 347 AK09912_REG_HZL}, 348 } 349}; 350 351/* 352 * Per-instance context data for the device. 353 */ 354struct ak8975_data { 355 struct i2c_client *client; 356 const struct ak_def *def; 357 struct mutex lock; 358 u8 asa[3]; 359 long raw_to_gauss[3]; 360 struct gpio_desc *eoc_gpiod; 361 struct gpio_desc *reset_gpiod; 362 int eoc_irq; 363 wait_queue_head_t data_ready_queue; 364 unsigned long flags; 365 u8 cntl_cache; 366 struct iio_mount_matrix orientation; 367 struct regulator *vdd; 368 struct regulator *vid; 369 370 /* Ensure natural alignment of timestamp */ 371 struct { 372 s16 channels[3]; 373 s64 ts __aligned(8); 374 } scan; 375}; 376 377/* Enable attached power regulator if any. */ 378static int ak8975_power_on(const struct ak8975_data *data) 379{ 380 int ret; 381 382 ret = regulator_enable(data->vdd); 383 if (ret) { 384 dev_warn(&data->client->dev, 385 "Failed to enable specified Vdd supply\n"); 386 return ret; 387 } 388 ret = regulator_enable(data->vid); 389 if (ret) { 390 dev_warn(&data->client->dev, 391 "Failed to enable specified Vid supply\n"); 392 regulator_disable(data->vdd); 393 return ret; 394 } 395 396 gpiod_set_value_cansleep(data->reset_gpiod, 0); 397 398 /* 399 * According to the datasheet the power supply rise time is 200us 400 * and the minimum wait time before mode setting is 100us, in 401 * total 300us. Add some margin and say minimum 500us here. 402 */ 403 usleep_range(500, 1000); 404 return 0; 405} 406 407/* Disable attached power regulator if any. */ 408static void ak8975_power_off(const struct ak8975_data *data) 409{ 410 gpiod_set_value_cansleep(data->reset_gpiod, 1); 411 412 regulator_disable(data->vid); 413 regulator_disable(data->vdd); 414} 415 416/* 417 * Return 0 if the i2c device is the one we expect. 418 * return a negative error number otherwise 419 */ 420static int ak8975_who_i_am(struct i2c_client *client, 421 enum asahi_compass_chipset type) 422{ 423 u8 wia_val[2]; 424 int ret; 425 426 /* 427 * Signature for each device: 428 * Device | WIA1 | WIA2 429 * AK09912 | DEVICE_ID | AK09912_DEVICE_ID 430 * AK09911 | DEVICE_ID | AK09911_DEVICE_ID 431 * AK8975 | DEVICE_ID | NA 432 * AK8963 | DEVICE_ID | NA 433 */ 434 ret = i2c_smbus_read_i2c_block_data_or_emulated( 435 client, AK09912_REG_WIA1, 2, wia_val); 436 if (ret < 0) { 437 dev_err(&client->dev, "Error reading WIA\n"); 438 return ret; 439 } 440 441 if (wia_val[0] != AK8975_DEVICE_ID) 442 return -ENODEV; 443 444 switch (type) { 445 case AK8975: 446 case AK8963: 447 return 0; 448 case AK09911: 449 if (wia_val[1] == AK09911_DEVICE_ID) 450 return 0; 451 break; 452 case AK09912: 453 if (wia_val[1] == AK09912_DEVICE_ID) 454 return 0; 455 break; 456 default: 457 dev_err(&client->dev, "Type %d unknown\n", type); 458 } 459 return -ENODEV; 460} 461 462/* 463 * Helper function to write to CNTL register. 464 */ 465static int ak8975_set_mode(struct ak8975_data *data, enum ak_ctrl_mode mode) 466{ 467 u8 regval; 468 int ret; 469 470 regval = (data->cntl_cache & ~data->def->ctrl_masks[CNTL_MODE]) | 471 data->def->ctrl_modes[mode]; 472 ret = i2c_smbus_write_byte_data(data->client, 473 data->def->ctrl_regs[CNTL], regval); 474 if (ret < 0) { 475 return ret; 476 } 477 data->cntl_cache = regval; 478 /* After mode change wait atleast 100us */ 479 usleep_range(100, 500); 480 481 return 0; 482} 483 484/* 485 * Handle data ready irq 486 */ 487static irqreturn_t ak8975_irq_handler(int irq, void *data) 488{ 489 struct ak8975_data *ak8975 = data; 490 491 set_bit(0, &ak8975->flags); 492 wake_up(&ak8975->data_ready_queue); 493 494 return IRQ_HANDLED; 495} 496 497/* 498 * Install data ready interrupt handler 499 */ 500static int ak8975_setup_irq(struct ak8975_data *data) 501{ 502 struct i2c_client *client = data->client; 503 int rc; 504 int irq; 505 506 init_waitqueue_head(&data->data_ready_queue); 507 clear_bit(0, &data->flags); 508 if (client->irq) 509 irq = client->irq; 510 else 511 irq = gpiod_to_irq(data->eoc_gpiod); 512 513 rc = devm_request_irq(&client->dev, irq, ak8975_irq_handler, 514 IRQF_TRIGGER_RISING | IRQF_ONESHOT, 515 dev_name(&client->dev), data); 516 if (rc < 0) { 517 dev_err(&client->dev, "irq %d request failed: %d\n", irq, rc); 518 return rc; 519 } 520 521 data->eoc_irq = irq; 522 523 return rc; 524} 525 526 527/* 528 * Perform some start-of-day setup, including reading the asa calibration 529 * values and caching them. 530 */ 531static int ak8975_setup(struct i2c_client *client) 532{ 533 struct iio_dev *indio_dev = i2c_get_clientdata(client); 534 struct ak8975_data *data = iio_priv(indio_dev); 535 int ret; 536 537 /* Write the fused rom access mode. */ 538 ret = ak8975_set_mode(data, FUSE_ROM); 539 if (ret < 0) { 540 dev_err(&client->dev, "Error in setting fuse access mode\n"); 541 return ret; 542 } 543 544 /* Get asa data and store in the device data. */ 545 ret = i2c_smbus_read_i2c_block_data_or_emulated( 546 client, data->def->ctrl_regs[ASA_BASE], 547 3, data->asa); 548 if (ret < 0) { 549 dev_err(&client->dev, "Not able to read asa data\n"); 550 return ret; 551 } 552 553 /* After reading fuse ROM data set power-down mode */ 554 ret = ak8975_set_mode(data, POWER_DOWN); 555 if (ret < 0) { 556 dev_err(&client->dev, "Error in setting power-down mode\n"); 557 return ret; 558 } 559 560 if (data->eoc_gpiod || client->irq > 0) { 561 ret = ak8975_setup_irq(data); 562 if (ret < 0) { 563 dev_err(&client->dev, 564 "Error setting data ready interrupt\n"); 565 return ret; 566 } 567 } 568 569 data->raw_to_gauss[0] = data->def->raw_to_gauss(data->asa[0]); 570 data->raw_to_gauss[1] = data->def->raw_to_gauss(data->asa[1]); 571 data->raw_to_gauss[2] = data->def->raw_to_gauss(data->asa[2]); 572 573 return 0; 574} 575 576static int wait_conversion_complete_gpio(struct ak8975_data *data) 577{ 578 struct i2c_client *client = data->client; 579 u32 timeout_ms = AK8975_MAX_CONVERSION_TIMEOUT; 580 int ret; 581 582 /* Wait for the conversion to complete. */ 583 while (timeout_ms) { 584 msleep(AK8975_CONVERSION_DONE_POLL_TIME); 585 if (gpiod_get_value(data->eoc_gpiod)) 586 break; 587 timeout_ms -= AK8975_CONVERSION_DONE_POLL_TIME; 588 } 589 if (!timeout_ms) { 590 dev_err(&client->dev, "Conversion timeout happened\n"); 591 return -EINVAL; 592 } 593 594 ret = i2c_smbus_read_byte_data(client, data->def->ctrl_regs[ST1]); 595 if (ret < 0) 596 dev_err(&client->dev, "Error in reading ST1\n"); 597 598 return ret; 599} 600 601static int wait_conversion_complete_polled(struct ak8975_data *data) 602{ 603 struct i2c_client *client = data->client; 604 u8 read_status; 605 u32 timeout_ms = AK8975_MAX_CONVERSION_TIMEOUT; 606 int ret; 607 608 /* Wait for the conversion to complete. */ 609 while (timeout_ms) { 610 msleep(AK8975_CONVERSION_DONE_POLL_TIME); 611 ret = i2c_smbus_read_byte_data(client, 612 data->def->ctrl_regs[ST1]); 613 if (ret < 0) { 614 dev_err(&client->dev, "Error in reading ST1\n"); 615 return ret; 616 } 617 read_status = ret; 618 if (read_status) 619 break; 620 timeout_ms -= AK8975_CONVERSION_DONE_POLL_TIME; 621 } 622 if (!timeout_ms) { 623 dev_err(&client->dev, "Conversion timeout happened\n"); 624 return -EINVAL; 625 } 626 627 return read_status; 628} 629 630/* Returns 0 if the end of conversion interrupt occured or -ETIME otherwise */ 631static int wait_conversion_complete_interrupt(struct ak8975_data *data) 632{ 633 int ret; 634 635 ret = wait_event_timeout(data->data_ready_queue, 636 test_bit(0, &data->flags), 637 AK8975_DATA_READY_TIMEOUT); 638 clear_bit(0, &data->flags); 639 640 return ret > 0 ? 0 : -ETIME; 641} 642 643static int ak8975_start_read_axis(struct ak8975_data *data, 644 const struct i2c_client *client) 645{ 646 /* Set up the device for taking a sample. */ 647 int ret = ak8975_set_mode(data, MODE_ONCE); 648 649 if (ret < 0) { 650 dev_err(&client->dev, "Error in setting operating mode\n"); 651 return ret; 652 } 653 654 /* Wait for the conversion to complete. */ 655 if (data->eoc_irq) 656 ret = wait_conversion_complete_interrupt(data); 657 else if (data->eoc_gpiod) 658 ret = wait_conversion_complete_gpio(data); 659 else 660 ret = wait_conversion_complete_polled(data); 661 if (ret < 0) 662 return ret; 663 664 /* This will be executed only for non-interrupt based waiting case */ 665 if (ret & data->def->ctrl_masks[ST1_DRDY]) { 666 ret = i2c_smbus_read_byte_data(client, 667 data->def->ctrl_regs[ST2]); 668 if (ret < 0) { 669 dev_err(&client->dev, "Error in reading ST2\n"); 670 return ret; 671 } 672 if (ret & (data->def->ctrl_masks[ST2_DERR] | 673 data->def->ctrl_masks[ST2_HOFL])) { 674 dev_err(&client->dev, "ST2 status error 0x%x\n", ret); 675 return -EINVAL; 676 } 677 } 678 679 return 0; 680} 681 682/* Retrieve raw flux value for one of the x, y, or z axis. */ 683static int ak8975_read_axis(struct iio_dev *indio_dev, int index, int *val) 684{ 685 struct ak8975_data *data = iio_priv(indio_dev); 686 const struct i2c_client *client = data->client; 687 const struct ak_def *def = data->def; 688 __le16 rval; 689 u16 buff; 690 int ret; 691 692 pm_runtime_get_sync(&data->client->dev); 693 694 mutex_lock(&data->lock); 695 696 ret = ak8975_start_read_axis(data, client); 697 if (ret) 698 goto exit; 699 700 ret = i2c_smbus_read_i2c_block_data_or_emulated( 701 client, def->data_regs[index], 702 sizeof(rval), (u8*)&rval); 703 if (ret < 0) 704 goto exit; 705 706 mutex_unlock(&data->lock); 707 708 pm_runtime_mark_last_busy(&data->client->dev); 709 pm_runtime_put_autosuspend(&data->client->dev); 710 711 /* Swap bytes and convert to valid range. */ 712 buff = le16_to_cpu(rval); 713 *val = clamp_t(s16, buff, -def->range, def->range); 714 return IIO_VAL_INT; 715 716exit: 717 mutex_unlock(&data->lock); 718 dev_err(&client->dev, "Error in reading axis\n"); 719 return ret; 720} 721 722static int ak8975_read_raw(struct iio_dev *indio_dev, 723 struct iio_chan_spec const *chan, 724 int *val, int *val2, 725 long mask) 726{ 727 struct ak8975_data *data = iio_priv(indio_dev); 728 729 switch (mask) { 730 case IIO_CHAN_INFO_RAW: 731 return ak8975_read_axis(indio_dev, chan->address, val); 732 case IIO_CHAN_INFO_SCALE: 733 *val = 0; 734 *val2 = data->raw_to_gauss[chan->address]; 735 return IIO_VAL_INT_PLUS_MICRO; 736 } 737 return -EINVAL; 738} 739 740static const struct iio_mount_matrix * 741ak8975_get_mount_matrix(const struct iio_dev *indio_dev, 742 const struct iio_chan_spec *chan) 743{ 744 struct ak8975_data *data = iio_priv(indio_dev); 745 746 return &data->orientation; 747} 748 749static const struct iio_chan_spec_ext_info ak8975_ext_info[] = { 750 IIO_MOUNT_MATRIX(IIO_SHARED_BY_DIR, ak8975_get_mount_matrix), 751 { } 752}; 753 754#define AK8975_CHANNEL(axis, index) \ 755 { \ 756 .type = IIO_MAGN, \ 757 .modified = 1, \ 758 .channel2 = IIO_MOD_##axis, \ 759 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \ 760 BIT(IIO_CHAN_INFO_SCALE), \ 761 .address = index, \ 762 .scan_index = index, \ 763 .scan_type = { \ 764 .sign = 's', \ 765 .realbits = 16, \ 766 .storagebits = 16, \ 767 .endianness = IIO_CPU \ 768 }, \ 769 .ext_info = ak8975_ext_info, \ 770 } 771 772static const struct iio_chan_spec ak8975_channels[] = { 773 AK8975_CHANNEL(X, 0), AK8975_CHANNEL(Y, 1), AK8975_CHANNEL(Z, 2), 774 IIO_CHAN_SOFT_TIMESTAMP(3), 775}; 776 777static const unsigned long ak8975_scan_masks[] = { 0x7, 0 }; 778 779static const struct iio_info ak8975_info = { 780 .read_raw = &ak8975_read_raw, 781}; 782 783static const struct acpi_device_id ak_acpi_match[] = { 784 {"AK8975", AK8975}, 785 {"AK8963", AK8963}, 786 {"INVN6500", AK8963}, 787 {"AK009911", AK09911}, 788 {"AK09911", AK09911}, 789 {"AKM9911", AK09911}, 790 {"AK09912", AK09912}, 791 { } 792}; 793MODULE_DEVICE_TABLE(acpi, ak_acpi_match); 794 795static void ak8975_fill_buffer(struct iio_dev *indio_dev) 796{ 797 struct ak8975_data *data = iio_priv(indio_dev); 798 const struct i2c_client *client = data->client; 799 const struct ak_def *def = data->def; 800 int ret; 801 __le16 fval[3]; 802 803 mutex_lock(&data->lock); 804 805 ret = ak8975_start_read_axis(data, client); 806 if (ret) 807 goto unlock; 808 809 /* 810 * For each axis, read the flux value from the appropriate register 811 * (the register is specified in the iio device attributes). 812 */ 813 ret = i2c_smbus_read_i2c_block_data_or_emulated(client, 814 def->data_regs[0], 815 3 * sizeof(fval[0]), 816 (u8 *)fval); 817 if (ret < 0) 818 goto unlock; 819 820 mutex_unlock(&data->lock); 821 822 /* Clamp to valid range. */ 823 data->scan.channels[0] = clamp_t(s16, le16_to_cpu(fval[0]), -def->range, def->range); 824 data->scan.channels[1] = clamp_t(s16, le16_to_cpu(fval[1]), -def->range, def->range); 825 data->scan.channels[2] = clamp_t(s16, le16_to_cpu(fval[2]), -def->range, def->range); 826 827 iio_push_to_buffers_with_timestamp(indio_dev, &data->scan, 828 iio_get_time_ns(indio_dev)); 829 830 return; 831 832unlock: 833 mutex_unlock(&data->lock); 834 dev_err(&client->dev, "Error in reading axes block\n"); 835} 836 837static irqreturn_t ak8975_handle_trigger(int irq, void *p) 838{ 839 const struct iio_poll_func *pf = p; 840 struct iio_dev *indio_dev = pf->indio_dev; 841 842 ak8975_fill_buffer(indio_dev); 843 iio_trigger_notify_done(indio_dev->trig); 844 return IRQ_HANDLED; 845} 846 847static int ak8975_probe(struct i2c_client *client, 848 const struct i2c_device_id *id) 849{ 850 struct ak8975_data *data; 851 struct iio_dev *indio_dev; 852 struct gpio_desc *eoc_gpiod; 853 struct gpio_desc *reset_gpiod; 854 const void *match; 855 unsigned int i; 856 int err; 857 enum asahi_compass_chipset chipset; 858 const char *name = NULL; 859 860 /* 861 * Grab and set up the supplied GPIO. 862 * We may not have a GPIO based IRQ to scan, that is fine, we will 863 * poll if so. 864 */ 865 eoc_gpiod = devm_gpiod_get_optional(&client->dev, NULL, GPIOD_IN); 866 if (IS_ERR(eoc_gpiod)) 867 return PTR_ERR(eoc_gpiod); 868 if (eoc_gpiod) 869 gpiod_set_consumer_name(eoc_gpiod, "ak_8975"); 870 871 /* 872 * According to AK09911 datasheet, if reset GPIO is provided then 873 * deassert reset on ak8975_power_on() and assert reset on 874 * ak8975_power_off(). 875 */ 876 reset_gpiod = devm_gpiod_get_optional(&client->dev, 877 "reset", GPIOD_OUT_HIGH); 878 if (IS_ERR(reset_gpiod)) 879 return PTR_ERR(reset_gpiod); 880 881 /* Register with IIO */ 882 indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data)); 883 if (indio_dev == NULL) 884 return -ENOMEM; 885 886 data = iio_priv(indio_dev); 887 i2c_set_clientdata(client, indio_dev); 888 889 data->client = client; 890 data->eoc_gpiod = eoc_gpiod; 891 data->reset_gpiod = reset_gpiod; 892 data->eoc_irq = 0; 893 894 err = iio_read_mount_matrix(&client->dev, "mount-matrix", &data->orientation); 895 if (err) 896 return err; 897 898 /* id will be NULL when enumerated via ACPI */ 899 match = device_get_match_data(&client->dev); 900 if (match) { 901 chipset = (enum asahi_compass_chipset)(match); 902 name = dev_name(&client->dev); 903 } else if (id) { 904 chipset = (enum asahi_compass_chipset)(id->driver_data); 905 name = id->name; 906 } else 907 return -ENOSYS; 908 909 for (i = 0; i < ARRAY_SIZE(ak_def_array); i++) 910 if (ak_def_array[i].type == chipset) 911 break; 912 913 if (i == ARRAY_SIZE(ak_def_array)) { 914 dev_err(&client->dev, "AKM device type unsupported: %d\n", 915 chipset); 916 return -ENODEV; 917 } 918 919 data->def = &ak_def_array[i]; 920 921 /* Fetch the regulators */ 922 data->vdd = devm_regulator_get(&client->dev, "vdd"); 923 if (IS_ERR(data->vdd)) 924 return PTR_ERR(data->vdd); 925 data->vid = devm_regulator_get(&client->dev, "vid"); 926 if (IS_ERR(data->vid)) 927 return PTR_ERR(data->vid); 928 929 err = ak8975_power_on(data); 930 if (err) 931 return err; 932 933 err = ak8975_who_i_am(client, data->def->type); 934 if (err < 0) { 935 dev_err(&client->dev, "Unexpected device\n"); 936 goto power_off; 937 } 938 dev_dbg(&client->dev, "Asahi compass chip %s\n", name); 939 940 /* Perform some basic start-of-day setup of the device. */ 941 err = ak8975_setup(client); 942 if (err < 0) { 943 dev_err(&client->dev, "%s initialization fails\n", name); 944 goto power_off; 945 } 946 947 mutex_init(&data->lock); 948 indio_dev->channels = ak8975_channels; 949 indio_dev->num_channels = ARRAY_SIZE(ak8975_channels); 950 indio_dev->info = &ak8975_info; 951 indio_dev->available_scan_masks = ak8975_scan_masks; 952 indio_dev->modes = INDIO_DIRECT_MODE; 953 indio_dev->name = name; 954 955 err = iio_triggered_buffer_setup(indio_dev, NULL, ak8975_handle_trigger, 956 NULL); 957 if (err) { 958 dev_err(&client->dev, "triggered buffer setup failed\n"); 959 goto power_off; 960 } 961 962 err = iio_device_register(indio_dev); 963 if (err) { 964 dev_err(&client->dev, "device register failed\n"); 965 goto cleanup_buffer; 966 } 967 968 /* Enable runtime PM */ 969 pm_runtime_get_noresume(&client->dev); 970 pm_runtime_set_active(&client->dev); 971 pm_runtime_enable(&client->dev); 972 /* 973 * The device comes online in 500us, so add two orders of magnitude 974 * of delay before autosuspending: 50 ms. 975 */ 976 pm_runtime_set_autosuspend_delay(&client->dev, 50); 977 pm_runtime_use_autosuspend(&client->dev); 978 pm_runtime_put(&client->dev); 979 980 return 0; 981 982cleanup_buffer: 983 iio_triggered_buffer_cleanup(indio_dev); 984power_off: 985 ak8975_power_off(data); 986 return err; 987} 988 989static int ak8975_remove(struct i2c_client *client) 990{ 991 struct iio_dev *indio_dev = i2c_get_clientdata(client); 992 struct ak8975_data *data = iio_priv(indio_dev); 993 994 pm_runtime_get_sync(&client->dev); 995 pm_runtime_put_noidle(&client->dev); 996 pm_runtime_disable(&client->dev); 997 iio_device_unregister(indio_dev); 998 iio_triggered_buffer_cleanup(indio_dev); 999 ak8975_set_mode(data, POWER_DOWN); 1000 ak8975_power_off(data); 1001 1002 return 0; 1003} 1004 1005#ifdef CONFIG_PM 1006static int ak8975_runtime_suspend(struct device *dev) 1007{ 1008 struct i2c_client *client = to_i2c_client(dev); 1009 struct iio_dev *indio_dev = i2c_get_clientdata(client); 1010 struct ak8975_data *data = iio_priv(indio_dev); 1011 int ret; 1012 1013 /* Set the device in power down if it wasn't already */ 1014 ret = ak8975_set_mode(data, POWER_DOWN); 1015 if (ret < 0) { 1016 dev_err(&client->dev, "Error in setting power-down mode\n"); 1017 return ret; 1018 } 1019 /* Next cut the regulators */ 1020 ak8975_power_off(data); 1021 1022 return 0; 1023} 1024 1025static int ak8975_runtime_resume(struct device *dev) 1026{ 1027 struct i2c_client *client = to_i2c_client(dev); 1028 struct iio_dev *indio_dev = i2c_get_clientdata(client); 1029 struct ak8975_data *data = iio_priv(indio_dev); 1030 int ret; 1031 1032 /* Take up the regulators */ 1033 ak8975_power_on(data); 1034 /* 1035 * We come up in powered down mode, the reading routines will 1036 * put us in the mode to read values later. 1037 */ 1038 ret = ak8975_set_mode(data, POWER_DOWN); 1039 if (ret < 0) { 1040 dev_err(&client->dev, "Error in setting power-down mode\n"); 1041 return ret; 1042 } 1043 1044 return 0; 1045} 1046#endif /* CONFIG_PM */ 1047 1048static const struct dev_pm_ops ak8975_dev_pm_ops = { 1049 SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend, 1050 pm_runtime_force_resume) 1051 SET_RUNTIME_PM_OPS(ak8975_runtime_suspend, 1052 ak8975_runtime_resume, NULL) 1053}; 1054 1055static const struct i2c_device_id ak8975_id[] = { 1056 {"ak8975", AK8975}, 1057 {"ak8963", AK8963}, 1058 {"AK8963", AK8963}, 1059 {"ak09911", AK09911}, 1060 {"ak09912", AK09912}, 1061 {} 1062}; 1063 1064MODULE_DEVICE_TABLE(i2c, ak8975_id); 1065 1066static const struct of_device_id ak8975_of_match[] = { 1067 { .compatible = "asahi-kasei,ak8975", }, 1068 { .compatible = "ak8975", }, 1069 { .compatible = "asahi-kasei,ak8963", }, 1070 { .compatible = "ak8963", }, 1071 { .compatible = "asahi-kasei,ak09911", }, 1072 { .compatible = "ak09911", }, 1073 { .compatible = "asahi-kasei,ak09912", }, 1074 { .compatible = "ak09912", }, 1075 {} 1076}; 1077MODULE_DEVICE_TABLE(of, ak8975_of_match); 1078 1079static struct i2c_driver ak8975_driver = { 1080 .driver = { 1081 .name = "ak8975", 1082 .pm = &ak8975_dev_pm_ops, 1083 .of_match_table = ak8975_of_match, 1084 .acpi_match_table = ak_acpi_match, 1085 }, 1086 .probe = ak8975_probe, 1087 .remove = ak8975_remove, 1088 .id_table = ak8975_id, 1089}; 1090module_i2c_driver(ak8975_driver); 1091 1092MODULE_AUTHOR("Laxman Dewangan <ldewangan@nvidia.com>"); 1093MODULE_DESCRIPTION("AK8975 magnetometer driver"); 1094MODULE_LICENSE("GPL"); 1095