1// SPDX-License-Identifier: GPL-2.0-or-later 2/* 3 * Common library for ADIS16XXX devices 4 * 5 * Copyright 2012 Analog Devices Inc. 6 * Author: Lars-Peter Clausen <lars@metafoo.de> 7 */ 8 9#include <linux/delay.h> 10#include <linux/gpio/consumer.h> 11#include <linux/mutex.h> 12#include <linux/device.h> 13#include <linux/kernel.h> 14#include <linux/spi/spi.h> 15#include <linux/module.h> 16#include <asm/unaligned.h> 17 18#include <linux/iio/iio.h> 19#include <linux/iio/imu/adis.h> 20 21#define ADIS_MSC_CTRL_DATA_RDY_EN BIT(2) 22#define ADIS_MSC_CTRL_DATA_RDY_POL_HIGH BIT(1) 23#define ADIS_MSC_CTRL_DATA_RDY_DIO2 BIT(0) 24#define ADIS_GLOB_CMD_SW_RESET BIT(7) 25 26/** 27 * __adis_write_reg() - write N bytes to register (unlocked version) 28 * @adis: The adis device 29 * @reg: The address of the lower of the two registers 30 * @value: The value to write to device (up to 4 bytes) 31 * @size: The size of the @value (in bytes) 32 */ 33int __adis_write_reg(struct adis *adis, unsigned int reg, unsigned int value, 34 unsigned int size) 35{ 36 unsigned int page = reg / ADIS_PAGE_SIZE; 37 int ret, i; 38 struct spi_message msg; 39 struct spi_transfer xfers[] = { 40 { 41 .tx_buf = adis->tx, 42 .bits_per_word = 8, 43 .len = 2, 44 .cs_change = 1, 45 .delay.value = adis->data->write_delay, 46 .delay.unit = SPI_DELAY_UNIT_USECS, 47 .cs_change_delay.value = adis->data->cs_change_delay, 48 .cs_change_delay.unit = SPI_DELAY_UNIT_USECS, 49 }, { 50 .tx_buf = adis->tx + 2, 51 .bits_per_word = 8, 52 .len = 2, 53 .cs_change = 1, 54 .delay.value = adis->data->write_delay, 55 .delay.unit = SPI_DELAY_UNIT_USECS, 56 .cs_change_delay.value = adis->data->cs_change_delay, 57 .cs_change_delay.unit = SPI_DELAY_UNIT_USECS, 58 }, { 59 .tx_buf = adis->tx + 4, 60 .bits_per_word = 8, 61 .len = 2, 62 .cs_change = 1, 63 .delay.value = adis->data->write_delay, 64 .delay.unit = SPI_DELAY_UNIT_USECS, 65 .cs_change_delay.value = adis->data->cs_change_delay, 66 .cs_change_delay.unit = SPI_DELAY_UNIT_USECS, 67 }, { 68 .tx_buf = adis->tx + 6, 69 .bits_per_word = 8, 70 .len = 2, 71 .delay.value = adis->data->write_delay, 72 .delay.unit = SPI_DELAY_UNIT_USECS, 73 }, { 74 .tx_buf = adis->tx + 8, 75 .bits_per_word = 8, 76 .len = 2, 77 .delay.value = adis->data->write_delay, 78 .delay.unit = SPI_DELAY_UNIT_USECS, 79 }, 80 }; 81 82 spi_message_init(&msg); 83 84 if (adis->current_page != page) { 85 adis->tx[0] = ADIS_WRITE_REG(ADIS_REG_PAGE_ID); 86 adis->tx[1] = page; 87 spi_message_add_tail(&xfers[0], &msg); 88 } 89 90 switch (size) { 91 case 4: 92 adis->tx[8] = ADIS_WRITE_REG(reg + 3); 93 adis->tx[9] = (value >> 24) & 0xff; 94 adis->tx[6] = ADIS_WRITE_REG(reg + 2); 95 adis->tx[7] = (value >> 16) & 0xff; 96 fallthrough; 97 case 2: 98 adis->tx[4] = ADIS_WRITE_REG(reg + 1); 99 adis->tx[5] = (value >> 8) & 0xff; 100 fallthrough; 101 case 1: 102 adis->tx[2] = ADIS_WRITE_REG(reg); 103 adis->tx[3] = value & 0xff; 104 break; 105 default: 106 return -EINVAL; 107 } 108 109 xfers[size].cs_change = 0; 110 111 for (i = 1; i <= size; i++) 112 spi_message_add_tail(&xfers[i], &msg); 113 114 ret = spi_sync(adis->spi, &msg); 115 if (ret) { 116 dev_err(&adis->spi->dev, "Failed to write register 0x%02X: %d\n", 117 reg, ret); 118 } else { 119 adis->current_page = page; 120 } 121 122 return ret; 123} 124EXPORT_SYMBOL_NS_GPL(__adis_write_reg, IIO_ADISLIB); 125 126/** 127 * __adis_read_reg() - read N bytes from register (unlocked version) 128 * @adis: The adis device 129 * @reg: The address of the lower of the two registers 130 * @val: The value read back from the device 131 * @size: The size of the @val buffer 132 */ 133int __adis_read_reg(struct adis *adis, unsigned int reg, unsigned int *val, 134 unsigned int size) 135{ 136 unsigned int page = reg / ADIS_PAGE_SIZE; 137 struct spi_message msg; 138 int ret; 139 struct spi_transfer xfers[] = { 140 { 141 .tx_buf = adis->tx, 142 .bits_per_word = 8, 143 .len = 2, 144 .cs_change = 1, 145 .delay.value = adis->data->write_delay, 146 .delay.unit = SPI_DELAY_UNIT_USECS, 147 .cs_change_delay.value = adis->data->cs_change_delay, 148 .cs_change_delay.unit = SPI_DELAY_UNIT_USECS, 149 }, { 150 .tx_buf = adis->tx + 2, 151 .bits_per_word = 8, 152 .len = 2, 153 .cs_change = 1, 154 .delay.value = adis->data->read_delay, 155 .delay.unit = SPI_DELAY_UNIT_USECS, 156 .cs_change_delay.value = adis->data->cs_change_delay, 157 .cs_change_delay.unit = SPI_DELAY_UNIT_USECS, 158 }, { 159 .tx_buf = adis->tx + 4, 160 .rx_buf = adis->rx, 161 .bits_per_word = 8, 162 .len = 2, 163 .cs_change = 1, 164 .delay.value = adis->data->read_delay, 165 .delay.unit = SPI_DELAY_UNIT_USECS, 166 .cs_change_delay.value = adis->data->cs_change_delay, 167 .cs_change_delay.unit = SPI_DELAY_UNIT_USECS, 168 }, { 169 .rx_buf = adis->rx + 2, 170 .bits_per_word = 8, 171 .len = 2, 172 .delay.value = adis->data->read_delay, 173 .delay.unit = SPI_DELAY_UNIT_USECS, 174 }, 175 }; 176 177 spi_message_init(&msg); 178 179 if (adis->current_page != page) { 180 adis->tx[0] = ADIS_WRITE_REG(ADIS_REG_PAGE_ID); 181 adis->tx[1] = page; 182 spi_message_add_tail(&xfers[0], &msg); 183 } 184 185 switch (size) { 186 case 4: 187 adis->tx[2] = ADIS_READ_REG(reg + 2); 188 adis->tx[3] = 0; 189 spi_message_add_tail(&xfers[1], &msg); 190 fallthrough; 191 case 2: 192 adis->tx[4] = ADIS_READ_REG(reg); 193 adis->tx[5] = 0; 194 spi_message_add_tail(&xfers[2], &msg); 195 spi_message_add_tail(&xfers[3], &msg); 196 break; 197 default: 198 return -EINVAL; 199 } 200 201 ret = spi_sync(adis->spi, &msg); 202 if (ret) { 203 dev_err(&adis->spi->dev, "Failed to read register 0x%02X: %d\n", 204 reg, ret); 205 return ret; 206 } 207 208 adis->current_page = page; 209 210 switch (size) { 211 case 4: 212 *val = get_unaligned_be32(adis->rx); 213 break; 214 case 2: 215 *val = get_unaligned_be16(adis->rx + 2); 216 break; 217 } 218 219 return ret; 220} 221EXPORT_SYMBOL_NS_GPL(__adis_read_reg, IIO_ADISLIB); 222/** 223 * __adis_update_bits_base() - ADIS Update bits function - Unlocked version 224 * @adis: The adis device 225 * @reg: The address of the lower of the two registers 226 * @mask: Bitmask to change 227 * @val: Value to be written 228 * @size: Size of the register to update 229 * 230 * Updates the desired bits of @reg in accordance with @mask and @val. 231 */ 232int __adis_update_bits_base(struct adis *adis, unsigned int reg, const u32 mask, 233 const u32 val, u8 size) 234{ 235 int ret; 236 u32 __val; 237 238 ret = __adis_read_reg(adis, reg, &__val, size); 239 if (ret) 240 return ret; 241 242 __val = (__val & ~mask) | (val & mask); 243 244 return __adis_write_reg(adis, reg, __val, size); 245} 246EXPORT_SYMBOL_NS_GPL(__adis_update_bits_base, IIO_ADISLIB); 247 248#ifdef CONFIG_DEBUG_FS 249 250int adis_debugfs_reg_access(struct iio_dev *indio_dev, unsigned int reg, 251 unsigned int writeval, unsigned int *readval) 252{ 253 struct adis *adis = iio_device_get_drvdata(indio_dev); 254 255 if (readval) { 256 u16 val16; 257 int ret; 258 259 ret = adis_read_reg_16(adis, reg, &val16); 260 if (ret == 0) 261 *readval = val16; 262 263 return ret; 264 } 265 266 return adis_write_reg_16(adis, reg, writeval); 267} 268EXPORT_SYMBOL_NS(adis_debugfs_reg_access, IIO_ADISLIB); 269 270#endif 271 272/** 273 * __adis_enable_irq() - Enable or disable data ready IRQ (unlocked) 274 * @adis: The adis device 275 * @enable: Whether to enable the IRQ 276 * 277 * Returns 0 on success, negative error code otherwise 278 */ 279int __adis_enable_irq(struct adis *adis, bool enable) 280{ 281 int ret; 282 u16 msc; 283 284 if (adis->data->enable_irq) 285 return adis->data->enable_irq(adis, enable); 286 287 if (adis->data->unmasked_drdy) { 288 if (enable) 289 enable_irq(adis->spi->irq); 290 else 291 disable_irq(adis->spi->irq); 292 293 return 0; 294 } 295 296 ret = __adis_read_reg_16(adis, adis->data->msc_ctrl_reg, &msc); 297 if (ret) 298 return ret; 299 300 msc |= ADIS_MSC_CTRL_DATA_RDY_POL_HIGH; 301 msc &= ~ADIS_MSC_CTRL_DATA_RDY_DIO2; 302 if (enable) 303 msc |= ADIS_MSC_CTRL_DATA_RDY_EN; 304 else 305 msc &= ~ADIS_MSC_CTRL_DATA_RDY_EN; 306 307 return __adis_write_reg_16(adis, adis->data->msc_ctrl_reg, msc); 308} 309EXPORT_SYMBOL_NS(__adis_enable_irq, IIO_ADISLIB); 310 311/** 312 * __adis_check_status() - Check the device for error conditions (unlocked) 313 * @adis: The adis device 314 * 315 * Returns 0 on success, a negative error code otherwise 316 */ 317int __adis_check_status(struct adis *adis) 318{ 319 u16 status; 320 int ret; 321 int i; 322 323 ret = __adis_read_reg_16(adis, adis->data->diag_stat_reg, &status); 324 if (ret) 325 return ret; 326 327 status &= adis->data->status_error_mask; 328 329 if (status == 0) 330 return 0; 331 332 for (i = 0; i < 16; ++i) { 333 if (status & BIT(i)) { 334 dev_err(&adis->spi->dev, "%s.\n", 335 adis->data->status_error_msgs[i]); 336 } 337 } 338 339 return -EIO; 340} 341EXPORT_SYMBOL_NS_GPL(__adis_check_status, IIO_ADISLIB); 342 343/** 344 * __adis_reset() - Reset the device (unlocked version) 345 * @adis: The adis device 346 * 347 * Returns 0 on success, a negative error code otherwise 348 */ 349int __adis_reset(struct adis *adis) 350{ 351 int ret; 352 const struct adis_timeout *timeouts = adis->data->timeouts; 353 354 ret = __adis_write_reg_8(adis, adis->data->glob_cmd_reg, 355 ADIS_GLOB_CMD_SW_RESET); 356 if (ret) { 357 dev_err(&adis->spi->dev, "Failed to reset device: %d\n", ret); 358 return ret; 359 } 360 361 msleep(timeouts->sw_reset_ms); 362 363 return 0; 364} 365EXPORT_SYMBOL_NS_GPL(__adis_reset, IIO_ADIS_LIB); 366 367static int adis_self_test(struct adis *adis) 368{ 369 int ret; 370 const struct adis_timeout *timeouts = adis->data->timeouts; 371 372 ret = __adis_write_reg_16(adis, adis->data->self_test_reg, 373 adis->data->self_test_mask); 374 if (ret) { 375 dev_err(&adis->spi->dev, "Failed to initiate self test: %d\n", 376 ret); 377 return ret; 378 } 379 380 msleep(timeouts->self_test_ms); 381 382 ret = __adis_check_status(adis); 383 384 if (adis->data->self_test_no_autoclear) 385 __adis_write_reg_16(adis, adis->data->self_test_reg, 0x00); 386 387 return ret; 388} 389 390/** 391 * __adis_initial_startup() - Device initial setup 392 * @adis: The adis device 393 * 394 * The function performs a HW reset via a reset pin that should be specified 395 * via GPIOLIB. If no pin is configured a SW reset will be performed. 396 * The RST pin for the ADIS devices should be configured as ACTIVE_LOW. 397 * 398 * After the self-test operation is performed, the function will also check 399 * that the product ID is as expected. This assumes that drivers providing 400 * 'prod_id_reg' will also provide the 'prod_id'. 401 * 402 * Returns 0 if the device is operational, a negative error code otherwise. 403 * 404 * This function should be called early on in the device initialization sequence 405 * to ensure that the device is in a sane and known state and that it is usable. 406 */ 407int __adis_initial_startup(struct adis *adis) 408{ 409 const struct adis_timeout *timeouts = adis->data->timeouts; 410 struct gpio_desc *gpio; 411 u16 prod_id; 412 int ret; 413 414 /* check if the device has rst pin low */ 415 gpio = devm_gpiod_get_optional(&adis->spi->dev, "reset", GPIOD_OUT_HIGH); 416 if (IS_ERR(gpio)) 417 return PTR_ERR(gpio); 418 419 if (gpio) { 420 usleep_range(10, 12); 421 /* bring device out of reset */ 422 gpiod_set_value_cansleep(gpio, 0); 423 msleep(timeouts->reset_ms); 424 } else { 425 ret = __adis_reset(adis); 426 if (ret) 427 return ret; 428 } 429 430 ret = adis_self_test(adis); 431 if (ret) 432 return ret; 433 434 /* 435 * don't bother calling this if we can't unmask the IRQ as in this case 436 * the IRQ is most likely not yet requested and we will request it 437 * with 'IRQF_NO_AUTOEN' anyways. 438 */ 439 if (!adis->data->unmasked_drdy) 440 __adis_enable_irq(adis, false); 441 442 if (!adis->data->prod_id_reg) 443 return 0; 444 445 ret = adis_read_reg_16(adis, adis->data->prod_id_reg, &prod_id); 446 if (ret) 447 return ret; 448 449 if (prod_id != adis->data->prod_id) 450 dev_warn(&adis->spi->dev, 451 "Device ID(%u) and product ID(%u) do not match.\n", 452 adis->data->prod_id, prod_id); 453 454 return 0; 455} 456EXPORT_SYMBOL_NS_GPL(__adis_initial_startup, IIO_ADISLIB); 457 458/** 459 * adis_single_conversion() - Performs a single sample conversion 460 * @indio_dev: The IIO device 461 * @chan: The IIO channel 462 * @error_mask: Mask for the error bit 463 * @val: Result of the conversion 464 * 465 * Returns IIO_VAL_INT on success, a negative error code otherwise. 466 * 467 * The function performs a single conversion on a given channel and post 468 * processes the value accordingly to the channel spec. If a error_mask is given 469 * the function will check if the mask is set in the returned raw value. If it 470 * is set the function will perform a self-check. If the device does not report 471 * a error bit in the channels raw value set error_mask to 0. 472 */ 473int adis_single_conversion(struct iio_dev *indio_dev, 474 const struct iio_chan_spec *chan, 475 unsigned int error_mask, int *val) 476{ 477 struct adis *adis = iio_device_get_drvdata(indio_dev); 478 unsigned int uval; 479 int ret; 480 481 mutex_lock(&adis->state_lock); 482 483 ret = __adis_read_reg(adis, chan->address, &uval, 484 chan->scan_type.storagebits / 8); 485 if (ret) 486 goto err_unlock; 487 488 if (uval & error_mask) { 489 ret = __adis_check_status(adis); 490 if (ret) 491 goto err_unlock; 492 } 493 494 if (chan->scan_type.sign == 's') 495 *val = sign_extend32(uval, chan->scan_type.realbits - 1); 496 else 497 *val = uval & ((1 << chan->scan_type.realbits) - 1); 498 499 ret = IIO_VAL_INT; 500err_unlock: 501 mutex_unlock(&adis->state_lock); 502 return ret; 503} 504EXPORT_SYMBOL_NS_GPL(adis_single_conversion, IIO_ADISLIB); 505 506/** 507 * adis_init() - Initialize adis device structure 508 * @adis: The adis device 509 * @indio_dev: The iio device 510 * @spi: The spi device 511 * @data: Chip specific data 512 * 513 * Returns 0 on success, a negative error code otherwise. 514 * 515 * This function must be called, before any other adis helper function may be 516 * called. 517 */ 518int adis_init(struct adis *adis, struct iio_dev *indio_dev, 519 struct spi_device *spi, const struct adis_data *data) 520{ 521 if (!data || !data->timeouts) { 522 dev_err(&spi->dev, "No config data or timeouts not defined!\n"); 523 return -EINVAL; 524 } 525 526 mutex_init(&adis->state_lock); 527 adis->spi = spi; 528 adis->data = data; 529 iio_device_set_drvdata(indio_dev, adis); 530 531 if (data->has_paging) { 532 /* Need to set the page before first read/write */ 533 adis->current_page = -1; 534 } else { 535 /* Page will always be 0 */ 536 adis->current_page = 0; 537 } 538 539 return 0; 540} 541EXPORT_SYMBOL_NS_GPL(adis_init, IIO_ADISLIB); 542 543MODULE_LICENSE("GPL"); 544MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>"); 545MODULE_DESCRIPTION("Common library code for ADIS16XXX devices"); 546