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 */ 33 int __adis_write_reg(struct adis *adis, unsigned int reg, 34 unsigned int value, 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 } 124 EXPORT_SYMBOL_GPL(__adis_write_reg); 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 */ 133 int __adis_read_reg(struct adis *adis, unsigned int reg, 134 unsigned int *val, 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 } else { 207 adis->current_page = page; 208 } 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 } 221 EXPORT_SYMBOL_GPL(__adis_read_reg); 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 */ 232 int __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 } 246 EXPORT_SYMBOL_GPL(__adis_update_bits_base); 247 248 #ifdef CONFIG_DEBUG_FS 249 250 int adis_debugfs_reg_access(struct iio_dev *indio_dev, 251 unsigned int reg, unsigned int writeval, unsigned int *readval) 252 { 253 struct adis *adis = iio_device_get_drvdata(indio_dev); 254 255 if (readval) { 256 uint16_t 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 } else { 265 return adis_write_reg_16(adis, reg, writeval); 266 } 267 } 268 EXPORT_SYMBOL(adis_debugfs_reg_access); 269 270 #endif 271 272 /** 273 * adis_enable_irq() - Enable or disable data ready IRQ 274 * @adis: The adis device 275 * @enable: Whether to enable the IRQ 276 * 277 * Returns 0 on success, negative error code otherwise 278 */ 279 int adis_enable_irq(struct adis *adis, bool enable) 280 { 281 int ret = 0; 282 uint16_t msc; 283 284 mutex_lock(&adis->state_lock); 285 286 if (adis->data->enable_irq) { 287 ret = adis->data->enable_irq(adis, enable); 288 goto out_unlock; 289 } 290 291 ret = __adis_read_reg_16(adis, adis->data->msc_ctrl_reg, &msc); 292 if (ret) 293 goto out_unlock; 294 295 msc |= ADIS_MSC_CTRL_DATA_RDY_POL_HIGH; 296 msc &= ~ADIS_MSC_CTRL_DATA_RDY_DIO2; 297 if (enable) 298 msc |= ADIS_MSC_CTRL_DATA_RDY_EN; 299 else 300 msc &= ~ADIS_MSC_CTRL_DATA_RDY_EN; 301 302 ret = __adis_write_reg_16(adis, adis->data->msc_ctrl_reg, msc); 303 304 out_unlock: 305 mutex_unlock(&adis->state_lock); 306 return ret; 307 } 308 EXPORT_SYMBOL(adis_enable_irq); 309 310 /** 311 * __adis_check_status() - Check the device for error conditions (unlocked) 312 * @adis: The adis device 313 * 314 * Returns 0 on success, a negative error code otherwise 315 */ 316 int __adis_check_status(struct adis *adis) 317 { 318 uint16_t status; 319 int ret; 320 int i; 321 322 ret = __adis_read_reg_16(adis, adis->data->diag_stat_reg, &status); 323 if (ret) 324 return ret; 325 326 status &= adis->data->status_error_mask; 327 328 if (status == 0) 329 return 0; 330 331 for (i = 0; i < 16; ++i) { 332 if (status & BIT(i)) { 333 dev_err(&adis->spi->dev, "%s.\n", 334 adis->data->status_error_msgs[i]); 335 } 336 } 337 338 return -EIO; 339 } 340 EXPORT_SYMBOL_GPL(__adis_check_status); 341 342 /** 343 * __adis_reset() - Reset the device (unlocked version) 344 * @adis: The adis device 345 * 346 * Returns 0 on success, a negative error code otherwise 347 */ 348 int __adis_reset(struct adis *adis) 349 { 350 int ret; 351 const struct adis_timeout *timeouts = adis->data->timeouts; 352 353 ret = __adis_write_reg_8(adis, adis->data->glob_cmd_reg, 354 ADIS_GLOB_CMD_SW_RESET); 355 if (ret) { 356 dev_err(&adis->spi->dev, "Failed to reset device: %d\n", ret); 357 return ret; 358 } 359 360 msleep(timeouts->sw_reset_ms); 361 362 return 0; 363 } 364 EXPORT_SYMBOL_GPL(__adis_reset); 365 366 static int adis_self_test(struct adis *adis) 367 { 368 int ret; 369 const struct adis_timeout *timeouts = adis->data->timeouts; 370 371 ret = __adis_write_reg_16(adis, adis->data->self_test_reg, 372 adis->data->self_test_mask); 373 if (ret) { 374 dev_err(&adis->spi->dev, "Failed to initiate self test: %d\n", 375 ret); 376 return ret; 377 } 378 379 msleep(timeouts->self_test_ms); 380 381 ret = __adis_check_status(adis); 382 383 if (adis->data->self_test_no_autoclear) 384 __adis_write_reg_16(adis, adis->data->self_test_reg, 0x00); 385 386 return ret; 387 } 388 389 /** 390 * __adis_initial_startup() - Device initial setup 391 * @adis: The adis device 392 * 393 * The function performs a HW reset via a reset pin that should be specified 394 * via GPIOLIB. If no pin is configured a SW reset will be performed. 395 * The RST pin for the ADIS devices should be configured as ACTIVE_LOW. 396 * 397 * After the self-test operation is performed, the function will also check 398 * that the product ID is as expected. This assumes that drivers providing 399 * 'prod_id_reg' will also provide the 'prod_id'. 400 * 401 * Returns 0 if the device is operational, a negative error code otherwise. 402 * 403 * This function should be called early on in the device initialization sequence 404 * to ensure that the device is in a sane and known state and that it is usable. 405 */ 406 int __adis_initial_startup(struct adis *adis) 407 { 408 const struct adis_timeout *timeouts = adis->data->timeouts; 409 struct gpio_desc *gpio; 410 uint16_t prod_id; 411 int ret; 412 413 /* check if the device has rst pin low */ 414 gpio = devm_gpiod_get_optional(&adis->spi->dev, "reset", GPIOD_OUT_HIGH); 415 if (IS_ERR(gpio)) 416 return PTR_ERR(gpio); 417 418 if (gpio) { 419 msleep(10); 420 /* bring device out of reset */ 421 gpiod_set_value_cansleep(gpio, 0); 422 msleep(timeouts->reset_ms); 423 } else { 424 ret = __adis_reset(adis); 425 if (ret) 426 return ret; 427 } 428 429 ret = adis_self_test(adis); 430 if (ret) 431 return ret; 432 433 if (!adis->data->prod_id_reg) 434 return 0; 435 436 ret = adis_read_reg_16(adis, adis->data->prod_id_reg, &prod_id); 437 if (ret) 438 return ret; 439 440 if (prod_id != adis->data->prod_id) 441 dev_warn(&adis->spi->dev, 442 "Device ID(%u) and product ID(%u) do not match.\n", 443 adis->data->prod_id, prod_id); 444 445 return 0; 446 } 447 EXPORT_SYMBOL_GPL(__adis_initial_startup); 448 449 /** 450 * adis_single_conversion() - Performs a single sample conversion 451 * @indio_dev: The IIO device 452 * @chan: The IIO channel 453 * @error_mask: Mask for the error bit 454 * @val: Result of the conversion 455 * 456 * Returns IIO_VAL_INT on success, a negative error code otherwise. 457 * 458 * The function performs a single conversion on a given channel and post 459 * processes the value accordingly to the channel spec. If a error_mask is given 460 * the function will check if the mask is set in the returned raw value. If it 461 * is set the function will perform a self-check. If the device does not report 462 * a error bit in the channels raw value set error_mask to 0. 463 */ 464 int adis_single_conversion(struct iio_dev *indio_dev, 465 const struct iio_chan_spec *chan, unsigned int error_mask, int *val) 466 { 467 struct adis *adis = iio_device_get_drvdata(indio_dev); 468 unsigned int uval; 469 int ret; 470 471 mutex_lock(&adis->state_lock); 472 473 ret = __adis_read_reg(adis, chan->address, &uval, 474 chan->scan_type.storagebits / 8); 475 if (ret) 476 goto err_unlock; 477 478 if (uval & error_mask) { 479 ret = __adis_check_status(adis); 480 if (ret) 481 goto err_unlock; 482 } 483 484 if (chan->scan_type.sign == 's') 485 *val = sign_extend32(uval, chan->scan_type.realbits - 1); 486 else 487 *val = uval & ((1 << chan->scan_type.realbits) - 1); 488 489 ret = IIO_VAL_INT; 490 err_unlock: 491 mutex_unlock(&adis->state_lock); 492 return ret; 493 } 494 EXPORT_SYMBOL_GPL(adis_single_conversion); 495 496 /** 497 * adis_init() - Initialize adis device structure 498 * @adis: The adis device 499 * @indio_dev: The iio device 500 * @spi: The spi device 501 * @data: Chip specific data 502 * 503 * Returns 0 on success, a negative error code otherwise. 504 * 505 * This function must be called, before any other adis helper function may be 506 * called. 507 */ 508 int adis_init(struct adis *adis, struct iio_dev *indio_dev, 509 struct spi_device *spi, const struct adis_data *data) 510 { 511 if (!data || !data->timeouts) { 512 dev_err(&spi->dev, "No config data or timeouts not defined!\n"); 513 return -EINVAL; 514 } 515 516 mutex_init(&adis->state_lock); 517 adis->spi = spi; 518 adis->data = data; 519 iio_device_set_drvdata(indio_dev, adis); 520 521 if (data->has_paging) { 522 /* Need to set the page before first read/write */ 523 adis->current_page = -1; 524 } else { 525 /* Page will always be 0 */ 526 adis->current_page = 0; 527 } 528 529 return adis_enable_irq(adis, false); 530 } 531 EXPORT_SYMBOL_GPL(adis_init); 532 533 MODULE_LICENSE("GPL"); 534 MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>"); 535 MODULE_DESCRIPTION("Common library code for ADIS16XXX devices"); 536