1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * This file is the ADC part of the STM32 DFSDM driver 4 * 5 * Copyright (C) 2017, STMicroelectronics - All Rights Reserved 6 * Author: Arnaud Pouliquen <arnaud.pouliquen@st.com>. 7 */ 8 9 #include <linux/dmaengine.h> 10 #include <linux/dma-mapping.h> 11 #include <linux/iio/adc/stm32-dfsdm-adc.h> 12 #include <linux/iio/buffer.h> 13 #include <linux/iio/hw-consumer.h> 14 #include <linux/iio/sysfs.h> 15 #include <linux/iio/timer/stm32-lptim-trigger.h> 16 #include <linux/iio/timer/stm32-timer-trigger.h> 17 #include <linux/iio/trigger.h> 18 #include <linux/iio/trigger_consumer.h> 19 #include <linux/iio/triggered_buffer.h> 20 #include <linux/interrupt.h> 21 #include <linux/module.h> 22 #include <linux/of_device.h> 23 #include <linux/platform_device.h> 24 #include <linux/regmap.h> 25 #include <linux/slab.h> 26 27 #include "stm32-dfsdm.h" 28 29 #define DFSDM_DMA_BUFFER_SIZE (4 * PAGE_SIZE) 30 31 /* Conversion timeout */ 32 #define DFSDM_TIMEOUT_US 100000 33 #define DFSDM_TIMEOUT (msecs_to_jiffies(DFSDM_TIMEOUT_US / 1000)) 34 35 /* Oversampling attribute default */ 36 #define DFSDM_DEFAULT_OVERSAMPLING 100 37 38 /* Oversampling max values */ 39 #define DFSDM_MAX_INT_OVERSAMPLING 256 40 #define DFSDM_MAX_FL_OVERSAMPLING 1024 41 42 /* Limit filter output resolution to 31 bits. (i.e. sample range is +/-2^30) */ 43 #define DFSDM_DATA_MAX BIT(30) 44 /* 45 * Data are output as two's complement data in a 24 bit field. 46 * Data from filters are in the range +/-2^(n-1) 47 * 2^(n-1) maximum positive value cannot be coded in 2's complement n bits 48 * An extra bit is required to avoid wrap-around of the binary code for 2^(n-1) 49 * So, the resolution of samples from filter is actually limited to 23 bits 50 */ 51 #define DFSDM_DATA_RES 24 52 53 /* Filter configuration */ 54 #define DFSDM_CR1_CFG_MASK (DFSDM_CR1_RCH_MASK | DFSDM_CR1_RCONT_MASK | \ 55 DFSDM_CR1_RSYNC_MASK | DFSDM_CR1_JSYNC_MASK | \ 56 DFSDM_CR1_JSCAN_MASK) 57 58 enum sd_converter_type { 59 DFSDM_AUDIO, 60 DFSDM_IIO, 61 }; 62 63 struct stm32_dfsdm_dev_data { 64 int type; 65 int (*init)(struct device *dev, struct iio_dev *indio_dev); 66 unsigned int num_channels; 67 const struct regmap_config *regmap_cfg; 68 }; 69 70 struct stm32_dfsdm_adc { 71 struct stm32_dfsdm *dfsdm; 72 const struct stm32_dfsdm_dev_data *dev_data; 73 unsigned int fl_id; 74 unsigned int nconv; 75 unsigned long smask; 76 77 /* ADC specific */ 78 unsigned int oversamp; 79 struct iio_hw_consumer *hwc; 80 struct completion completion; 81 u32 *buffer; 82 83 /* Audio specific */ 84 unsigned int spi_freq; /* SPI bus clock frequency */ 85 unsigned int sample_freq; /* Sample frequency after filter decimation */ 86 int (*cb)(const void *data, size_t size, void *cb_priv); 87 void *cb_priv; 88 89 /* DMA */ 90 u8 *rx_buf; 91 unsigned int bufi; /* Buffer current position */ 92 unsigned int buf_sz; /* Buffer size */ 93 struct dma_chan *dma_chan; 94 dma_addr_t dma_buf; 95 }; 96 97 struct stm32_dfsdm_str2field { 98 const char *name; 99 unsigned int val; 100 }; 101 102 /* DFSDM channel serial interface type */ 103 static const struct stm32_dfsdm_str2field stm32_dfsdm_chan_type[] = { 104 { "SPI_R", 0 }, /* SPI with data on rising edge */ 105 { "SPI_F", 1 }, /* SPI with data on falling edge */ 106 { "MANCH_R", 2 }, /* Manchester codec, rising edge = logic 0 */ 107 { "MANCH_F", 3 }, /* Manchester codec, falling edge = logic 1 */ 108 {}, 109 }; 110 111 /* DFSDM channel clock source */ 112 static const struct stm32_dfsdm_str2field stm32_dfsdm_chan_src[] = { 113 /* External SPI clock (CLKIN x) */ 114 { "CLKIN", DFSDM_CHANNEL_SPI_CLOCK_EXTERNAL }, 115 /* Internal SPI clock (CLKOUT) */ 116 { "CLKOUT", DFSDM_CHANNEL_SPI_CLOCK_INTERNAL }, 117 /* Internal SPI clock divided by 2 (falling edge) */ 118 { "CLKOUT_F", DFSDM_CHANNEL_SPI_CLOCK_INTERNAL_DIV2_FALLING }, 119 /* Internal SPI clock divided by 2 (falling edge) */ 120 { "CLKOUT_R", DFSDM_CHANNEL_SPI_CLOCK_INTERNAL_DIV2_RISING }, 121 {}, 122 }; 123 124 static int stm32_dfsdm_str2val(const char *str, 125 const struct stm32_dfsdm_str2field *list) 126 { 127 const struct stm32_dfsdm_str2field *p = list; 128 129 for (p = list; p && p->name; p++) 130 if (!strcmp(p->name, str)) 131 return p->val; 132 133 return -EINVAL; 134 } 135 136 /** 137 * struct stm32_dfsdm_trig_info - DFSDM trigger info 138 * @name: name of the trigger, corresponding to its source 139 * @jextsel: trigger signal selection 140 */ 141 struct stm32_dfsdm_trig_info { 142 const char *name; 143 unsigned int jextsel; 144 }; 145 146 /* hardware injected trigger enable, edge selection */ 147 enum stm32_dfsdm_jexten { 148 STM32_DFSDM_JEXTEN_DISABLED, 149 STM32_DFSDM_JEXTEN_RISING_EDGE, 150 STM32_DFSDM_JEXTEN_FALLING_EDGE, 151 STM32_DFSDM_EXTEN_BOTH_EDGES, 152 }; 153 154 static const struct stm32_dfsdm_trig_info stm32_dfsdm_trigs[] = { 155 { TIM1_TRGO, 0 }, 156 { TIM1_TRGO2, 1 }, 157 { TIM8_TRGO, 2 }, 158 { TIM8_TRGO2, 3 }, 159 { TIM3_TRGO, 4 }, 160 { TIM4_TRGO, 5 }, 161 { TIM16_OC1, 6 }, 162 { TIM6_TRGO, 7 }, 163 { TIM7_TRGO, 8 }, 164 { LPTIM1_OUT, 26 }, 165 { LPTIM2_OUT, 27 }, 166 { LPTIM3_OUT, 28 }, 167 {}, 168 }; 169 170 static int stm32_dfsdm_get_jextsel(struct iio_dev *indio_dev, 171 struct iio_trigger *trig) 172 { 173 int i; 174 175 /* lookup triggers registered by stm32 timer trigger driver */ 176 for (i = 0; stm32_dfsdm_trigs[i].name; i++) { 177 /** 178 * Checking both stm32 timer trigger type and trig name 179 * should be safe against arbitrary trigger names. 180 */ 181 if ((is_stm32_timer_trigger(trig) || 182 is_stm32_lptim_trigger(trig)) && 183 !strcmp(stm32_dfsdm_trigs[i].name, trig->name)) { 184 return stm32_dfsdm_trigs[i].jextsel; 185 } 186 } 187 188 return -EINVAL; 189 } 190 191 static int stm32_dfsdm_compute_osrs(struct stm32_dfsdm_filter *fl, 192 unsigned int fast, unsigned int oversamp) 193 { 194 unsigned int i, d, fosr, iosr; 195 u64 res, max; 196 int bits, shift; 197 unsigned int m = 1; /* multiplication factor */ 198 unsigned int p = fl->ford; /* filter order (ford) */ 199 struct stm32_dfsdm_filter_osr *flo = &fl->flo[fast]; 200 201 pr_debug("%s: Requested oversampling: %d\n", __func__, oversamp); 202 /* 203 * This function tries to compute filter oversampling and integrator 204 * oversampling, base on oversampling ratio requested by user. 205 * 206 * Decimation d depends on the filter order and the oversampling ratios. 207 * ford: filter order 208 * fosr: filter over sampling ratio 209 * iosr: integrator over sampling ratio 210 */ 211 if (fl->ford == DFSDM_FASTSINC_ORDER) { 212 m = 2; 213 p = 2; 214 } 215 216 /* 217 * Look for filter and integrator oversampling ratios which allows 218 * to maximize data output resolution. 219 */ 220 for (fosr = 1; fosr <= DFSDM_MAX_FL_OVERSAMPLING; fosr++) { 221 for (iosr = 1; iosr <= DFSDM_MAX_INT_OVERSAMPLING; iosr++) { 222 if (fast) 223 d = fosr * iosr; 224 else if (fl->ford == DFSDM_FASTSINC_ORDER) 225 d = fosr * (iosr + 3) + 2; 226 else 227 d = fosr * (iosr - 1 + p) + p; 228 229 if (d > oversamp) 230 break; 231 else if (d != oversamp) 232 continue; 233 /* 234 * Check resolution (limited to signed 32 bits) 235 * res <= 2^31 236 * Sincx filters: 237 * res = m * fosr^p x iosr (with m=1, p=ford) 238 * FastSinc filter 239 * res = m * fosr^p x iosr (with m=2, p=2) 240 */ 241 res = fosr; 242 for (i = p - 1; i > 0; i--) { 243 res = res * (u64)fosr; 244 if (res > DFSDM_DATA_MAX) 245 break; 246 } 247 if (res > DFSDM_DATA_MAX) 248 continue; 249 250 res = res * (u64)m * (u64)iosr; 251 if (res > DFSDM_DATA_MAX) 252 continue; 253 254 if (res >= flo->res) { 255 flo->res = res; 256 flo->fosr = fosr; 257 flo->iosr = iosr; 258 259 bits = fls(flo->res); 260 /* 8 LBSs in data register contain chan info */ 261 max = flo->res << 8; 262 263 /* if resolution is not a power of two */ 264 if (flo->res > BIT(bits - 1)) 265 bits++; 266 else 267 max--; 268 269 shift = DFSDM_DATA_RES - bits; 270 /* 271 * Compute right/left shift 272 * Right shift is performed by hardware 273 * when transferring samples to data register. 274 * Left shift is done by software on buffer 275 */ 276 if (shift > 0) { 277 /* Resolution is lower than 24 bits */ 278 flo->rshift = 0; 279 flo->lshift = shift; 280 } else { 281 /* 282 * If resolution is 24 bits or more, 283 * max positive value may be ambiguous 284 * (equal to max negative value as sign 285 * bit is dropped). 286 * Reduce resolution to 23 bits (rshift) 287 * to keep the sign on bit 23 and treat 288 * saturation before rescaling on 24 289 * bits (lshift). 290 */ 291 flo->rshift = 1 - shift; 292 flo->lshift = 1; 293 max >>= flo->rshift; 294 } 295 flo->max = (s32)max; 296 flo->bits = bits; 297 298 pr_debug("%s: fast %d, fosr %d, iosr %d, res 0x%llx/%d bits, rshift %d, lshift %d\n", 299 __func__, fast, flo->fosr, flo->iosr, 300 flo->res, bits, flo->rshift, 301 flo->lshift); 302 } 303 } 304 } 305 306 if (!flo->res) 307 return -EINVAL; 308 309 return 0; 310 } 311 312 static int stm32_dfsdm_compute_all_osrs(struct iio_dev *indio_dev, 313 unsigned int oversamp) 314 { 315 struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); 316 struct stm32_dfsdm_filter *fl = &adc->dfsdm->fl_list[adc->fl_id]; 317 int ret0, ret1; 318 319 memset(&fl->flo[0], 0, sizeof(fl->flo[0])); 320 memset(&fl->flo[1], 0, sizeof(fl->flo[1])); 321 322 ret0 = stm32_dfsdm_compute_osrs(fl, 0, oversamp); 323 ret1 = stm32_dfsdm_compute_osrs(fl, 1, oversamp); 324 if (ret0 < 0 && ret1 < 0) { 325 dev_err(&indio_dev->dev, 326 "Filter parameters not found: errors %d/%d\n", 327 ret0, ret1); 328 return -EINVAL; 329 } 330 331 return 0; 332 } 333 334 static int stm32_dfsdm_start_channel(struct iio_dev *indio_dev) 335 { 336 struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); 337 struct regmap *regmap = adc->dfsdm->regmap; 338 const struct iio_chan_spec *chan; 339 unsigned int bit; 340 int ret; 341 342 for_each_set_bit(bit, &adc->smask, sizeof(adc->smask) * BITS_PER_BYTE) { 343 chan = indio_dev->channels + bit; 344 ret = regmap_update_bits(regmap, DFSDM_CHCFGR1(chan->channel), 345 DFSDM_CHCFGR1_CHEN_MASK, 346 DFSDM_CHCFGR1_CHEN(1)); 347 if (ret < 0) 348 return ret; 349 } 350 351 return 0; 352 } 353 354 static void stm32_dfsdm_stop_channel(struct iio_dev *indio_dev) 355 { 356 struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); 357 struct regmap *regmap = adc->dfsdm->regmap; 358 const struct iio_chan_spec *chan; 359 unsigned int bit; 360 361 for_each_set_bit(bit, &adc->smask, sizeof(adc->smask) * BITS_PER_BYTE) { 362 chan = indio_dev->channels + bit; 363 regmap_update_bits(regmap, DFSDM_CHCFGR1(chan->channel), 364 DFSDM_CHCFGR1_CHEN_MASK, 365 DFSDM_CHCFGR1_CHEN(0)); 366 } 367 } 368 369 static int stm32_dfsdm_chan_configure(struct stm32_dfsdm *dfsdm, 370 struct stm32_dfsdm_channel *ch) 371 { 372 unsigned int id = ch->id; 373 struct regmap *regmap = dfsdm->regmap; 374 int ret; 375 376 ret = regmap_update_bits(regmap, DFSDM_CHCFGR1(id), 377 DFSDM_CHCFGR1_SITP_MASK, 378 DFSDM_CHCFGR1_SITP(ch->type)); 379 if (ret < 0) 380 return ret; 381 ret = regmap_update_bits(regmap, DFSDM_CHCFGR1(id), 382 DFSDM_CHCFGR1_SPICKSEL_MASK, 383 DFSDM_CHCFGR1_SPICKSEL(ch->src)); 384 if (ret < 0) 385 return ret; 386 return regmap_update_bits(regmap, DFSDM_CHCFGR1(id), 387 DFSDM_CHCFGR1_CHINSEL_MASK, 388 DFSDM_CHCFGR1_CHINSEL(ch->alt_si)); 389 } 390 391 static int stm32_dfsdm_start_filter(struct stm32_dfsdm_adc *adc, 392 unsigned int fl_id, 393 struct iio_trigger *trig) 394 { 395 struct stm32_dfsdm *dfsdm = adc->dfsdm; 396 int ret; 397 398 /* Enable filter */ 399 ret = regmap_update_bits(dfsdm->regmap, DFSDM_CR1(fl_id), 400 DFSDM_CR1_DFEN_MASK, DFSDM_CR1_DFEN(1)); 401 if (ret < 0) 402 return ret; 403 404 /* Nothing more to do for injected (scan mode/triggered) conversions */ 405 if (adc->nconv > 1 || trig) 406 return 0; 407 408 /* Software start (single or continuous) regular conversion */ 409 return regmap_update_bits(dfsdm->regmap, DFSDM_CR1(fl_id), 410 DFSDM_CR1_RSWSTART_MASK, 411 DFSDM_CR1_RSWSTART(1)); 412 } 413 414 static void stm32_dfsdm_stop_filter(struct stm32_dfsdm *dfsdm, 415 unsigned int fl_id) 416 { 417 /* Disable conversion */ 418 regmap_update_bits(dfsdm->regmap, DFSDM_CR1(fl_id), 419 DFSDM_CR1_DFEN_MASK, DFSDM_CR1_DFEN(0)); 420 } 421 422 static int stm32_dfsdm_filter_set_trig(struct iio_dev *indio_dev, 423 unsigned int fl_id, 424 struct iio_trigger *trig) 425 { 426 struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); 427 struct regmap *regmap = adc->dfsdm->regmap; 428 u32 jextsel = 0, jexten = STM32_DFSDM_JEXTEN_DISABLED; 429 int ret; 430 431 if (trig) { 432 ret = stm32_dfsdm_get_jextsel(indio_dev, trig); 433 if (ret < 0) 434 return ret; 435 436 /* set trigger source and polarity (default to rising edge) */ 437 jextsel = ret; 438 jexten = STM32_DFSDM_JEXTEN_RISING_EDGE; 439 } 440 441 ret = regmap_update_bits(regmap, DFSDM_CR1(fl_id), 442 DFSDM_CR1_JEXTSEL_MASK | DFSDM_CR1_JEXTEN_MASK, 443 DFSDM_CR1_JEXTSEL(jextsel) | 444 DFSDM_CR1_JEXTEN(jexten)); 445 if (ret < 0) 446 return ret; 447 448 return 0; 449 } 450 451 static int stm32_dfsdm_channels_configure(struct iio_dev *indio_dev, 452 unsigned int fl_id, 453 struct iio_trigger *trig) 454 { 455 struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); 456 struct regmap *regmap = adc->dfsdm->regmap; 457 struct stm32_dfsdm_filter *fl = &adc->dfsdm->fl_list[fl_id]; 458 struct stm32_dfsdm_filter_osr *flo = &fl->flo[0]; 459 const struct iio_chan_spec *chan; 460 unsigned int bit; 461 int ret; 462 463 fl->fast = 0; 464 465 /* 466 * In continuous mode, use fast mode configuration, 467 * if it provides a better resolution. 468 */ 469 if (adc->nconv == 1 && !trig && 470 (indio_dev->currentmode & INDIO_BUFFER_SOFTWARE)) { 471 if (fl->flo[1].res >= fl->flo[0].res) { 472 fl->fast = 1; 473 flo = &fl->flo[1]; 474 } 475 } 476 477 if (!flo->res) 478 return -EINVAL; 479 480 dev_dbg(&indio_dev->dev, "Samples actual resolution: %d bits", 481 min(flo->bits, (u32)DFSDM_DATA_RES - 1)); 482 483 for_each_set_bit(bit, &adc->smask, 484 sizeof(adc->smask) * BITS_PER_BYTE) { 485 chan = indio_dev->channels + bit; 486 487 ret = regmap_update_bits(regmap, 488 DFSDM_CHCFGR2(chan->channel), 489 DFSDM_CHCFGR2_DTRBS_MASK, 490 DFSDM_CHCFGR2_DTRBS(flo->rshift)); 491 if (ret) 492 return ret; 493 } 494 495 return 0; 496 } 497 498 static int stm32_dfsdm_filter_configure(struct iio_dev *indio_dev, 499 unsigned int fl_id, 500 struct iio_trigger *trig) 501 { 502 struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); 503 struct regmap *regmap = adc->dfsdm->regmap; 504 struct stm32_dfsdm_filter *fl = &adc->dfsdm->fl_list[fl_id]; 505 struct stm32_dfsdm_filter_osr *flo = &fl->flo[fl->fast]; 506 u32 cr1; 507 const struct iio_chan_spec *chan; 508 unsigned int bit, jchg = 0; 509 int ret; 510 511 /* Average integrator oversampling */ 512 ret = regmap_update_bits(regmap, DFSDM_FCR(fl_id), DFSDM_FCR_IOSR_MASK, 513 DFSDM_FCR_IOSR(flo->iosr - 1)); 514 if (ret) 515 return ret; 516 517 /* Filter order and Oversampling */ 518 ret = regmap_update_bits(regmap, DFSDM_FCR(fl_id), DFSDM_FCR_FOSR_MASK, 519 DFSDM_FCR_FOSR(flo->fosr - 1)); 520 if (ret) 521 return ret; 522 523 ret = regmap_update_bits(regmap, DFSDM_FCR(fl_id), DFSDM_FCR_FORD_MASK, 524 DFSDM_FCR_FORD(fl->ford)); 525 if (ret) 526 return ret; 527 528 ret = stm32_dfsdm_filter_set_trig(indio_dev, fl_id, trig); 529 if (ret) 530 return ret; 531 532 ret = regmap_update_bits(regmap, DFSDM_CR1(fl_id), 533 DFSDM_CR1_FAST_MASK, 534 DFSDM_CR1_FAST(fl->fast)); 535 if (ret) 536 return ret; 537 538 /* 539 * DFSDM modes configuration W.R.T audio/iio type modes 540 * ---------------------------------------------------------------- 541 * Modes | regular | regular | injected | injected | 542 * | | continuous | | + scan | 543 * --------------|---------|--------------|----------|------------| 544 * single conv | x | | | | 545 * (1 chan) | | | | | 546 * --------------|---------|--------------|----------|------------| 547 * 1 Audio chan | | sample freq | | | 548 * | | or sync_mode | | | 549 * --------------|---------|--------------|----------|------------| 550 * 1 IIO chan | | sample freq | trigger | | 551 * | | or sync_mode | | | 552 * --------------|---------|--------------|----------|------------| 553 * 2+ IIO chans | | | | trigger or | 554 * | | | | sync_mode | 555 * ---------------------------------------------------------------- 556 */ 557 if (adc->nconv == 1 && !trig) { 558 bit = __ffs(adc->smask); 559 chan = indio_dev->channels + bit; 560 561 /* Use regular conversion for single channel without trigger */ 562 cr1 = DFSDM_CR1_RCH(chan->channel); 563 564 /* Continuous conversions triggered by SPI clk in buffer mode */ 565 if (indio_dev->currentmode & INDIO_BUFFER_SOFTWARE) 566 cr1 |= DFSDM_CR1_RCONT(1); 567 568 cr1 |= DFSDM_CR1_RSYNC(fl->sync_mode); 569 } else { 570 /* Use injected conversion for multiple channels */ 571 for_each_set_bit(bit, &adc->smask, 572 sizeof(adc->smask) * BITS_PER_BYTE) { 573 chan = indio_dev->channels + bit; 574 jchg |= BIT(chan->channel); 575 } 576 ret = regmap_write(regmap, DFSDM_JCHGR(fl_id), jchg); 577 if (ret < 0) 578 return ret; 579 580 /* Use scan mode for multiple channels */ 581 cr1 = DFSDM_CR1_JSCAN((adc->nconv > 1) ? 1 : 0); 582 583 /* 584 * Continuous conversions not supported in injected mode, 585 * either use: 586 * - conversions in sync with filter 0 587 * - triggered conversions 588 */ 589 if (!fl->sync_mode && !trig) 590 return -EINVAL; 591 cr1 |= DFSDM_CR1_JSYNC(fl->sync_mode); 592 } 593 594 return regmap_update_bits(regmap, DFSDM_CR1(fl_id), DFSDM_CR1_CFG_MASK, 595 cr1); 596 } 597 598 static int stm32_dfsdm_channel_parse_of(struct stm32_dfsdm *dfsdm, 599 struct iio_dev *indio_dev, 600 struct iio_chan_spec *ch) 601 { 602 struct stm32_dfsdm_channel *df_ch; 603 const char *of_str; 604 int chan_idx = ch->scan_index; 605 int ret, val; 606 607 ret = of_property_read_u32_index(indio_dev->dev.of_node, 608 "st,adc-channels", chan_idx, 609 &ch->channel); 610 if (ret < 0) { 611 dev_err(&indio_dev->dev, 612 " Error parsing 'st,adc-channels' for idx %d\n", 613 chan_idx); 614 return ret; 615 } 616 if (ch->channel >= dfsdm->num_chs) { 617 dev_err(&indio_dev->dev, 618 " Error bad channel number %d (max = %d)\n", 619 ch->channel, dfsdm->num_chs); 620 return -EINVAL; 621 } 622 623 ret = of_property_read_string_index(indio_dev->dev.of_node, 624 "st,adc-channel-names", chan_idx, 625 &ch->datasheet_name); 626 if (ret < 0) { 627 dev_err(&indio_dev->dev, 628 " Error parsing 'st,adc-channel-names' for idx %d\n", 629 chan_idx); 630 return ret; 631 } 632 633 df_ch = &dfsdm->ch_list[ch->channel]; 634 df_ch->id = ch->channel; 635 636 ret = of_property_read_string_index(indio_dev->dev.of_node, 637 "st,adc-channel-types", chan_idx, 638 &of_str); 639 if (!ret) { 640 val = stm32_dfsdm_str2val(of_str, stm32_dfsdm_chan_type); 641 if (val < 0) 642 return val; 643 } else { 644 val = 0; 645 } 646 df_ch->type = val; 647 648 ret = of_property_read_string_index(indio_dev->dev.of_node, 649 "st,adc-channel-clk-src", chan_idx, 650 &of_str); 651 if (!ret) { 652 val = stm32_dfsdm_str2val(of_str, stm32_dfsdm_chan_src); 653 if (val < 0) 654 return val; 655 } else { 656 val = 0; 657 } 658 df_ch->src = val; 659 660 ret = of_property_read_u32_index(indio_dev->dev.of_node, 661 "st,adc-alt-channel", chan_idx, 662 &df_ch->alt_si); 663 if (ret < 0) 664 df_ch->alt_si = 0; 665 666 return 0; 667 } 668 669 static ssize_t dfsdm_adc_audio_get_spiclk(struct iio_dev *indio_dev, 670 uintptr_t priv, 671 const struct iio_chan_spec *chan, 672 char *buf) 673 { 674 struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); 675 676 return snprintf(buf, PAGE_SIZE, "%d\n", adc->spi_freq); 677 } 678 679 static int dfsdm_adc_set_samp_freq(struct iio_dev *indio_dev, 680 unsigned int sample_freq, 681 unsigned int spi_freq) 682 { 683 struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); 684 unsigned int oversamp; 685 int ret; 686 687 oversamp = DIV_ROUND_CLOSEST(spi_freq, sample_freq); 688 if (spi_freq % sample_freq) 689 dev_dbg(&indio_dev->dev, 690 "Rate not accurate. requested (%u), actual (%u)\n", 691 sample_freq, spi_freq / oversamp); 692 693 ret = stm32_dfsdm_compute_all_osrs(indio_dev, oversamp); 694 if (ret < 0) 695 return ret; 696 697 adc->sample_freq = spi_freq / oversamp; 698 adc->oversamp = oversamp; 699 700 return 0; 701 } 702 703 static ssize_t dfsdm_adc_audio_set_spiclk(struct iio_dev *indio_dev, 704 uintptr_t priv, 705 const struct iio_chan_spec *chan, 706 const char *buf, size_t len) 707 { 708 struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); 709 struct stm32_dfsdm_channel *ch = &adc->dfsdm->ch_list[chan->channel]; 710 unsigned int sample_freq = adc->sample_freq; 711 unsigned int spi_freq; 712 int ret; 713 714 dev_err(&indio_dev->dev, "enter %s\n", __func__); 715 /* If DFSDM is master on SPI, SPI freq can not be updated */ 716 if (ch->src != DFSDM_CHANNEL_SPI_CLOCK_EXTERNAL) 717 return -EPERM; 718 719 ret = kstrtoint(buf, 0, &spi_freq); 720 if (ret) 721 return ret; 722 723 if (!spi_freq) 724 return -EINVAL; 725 726 if (sample_freq) { 727 ret = dfsdm_adc_set_samp_freq(indio_dev, sample_freq, spi_freq); 728 if (ret < 0) 729 return ret; 730 } 731 adc->spi_freq = spi_freq; 732 733 return len; 734 } 735 736 static int stm32_dfsdm_start_conv(struct iio_dev *indio_dev, 737 struct iio_trigger *trig) 738 { 739 struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); 740 struct regmap *regmap = adc->dfsdm->regmap; 741 int ret; 742 743 ret = stm32_dfsdm_channels_configure(indio_dev, adc->fl_id, trig); 744 if (ret < 0) 745 return ret; 746 747 ret = stm32_dfsdm_start_channel(indio_dev); 748 if (ret < 0) 749 return ret; 750 751 ret = stm32_dfsdm_filter_configure(indio_dev, adc->fl_id, trig); 752 if (ret < 0) 753 goto stop_channels; 754 755 ret = stm32_dfsdm_start_filter(adc, adc->fl_id, trig); 756 if (ret < 0) 757 goto filter_unconfigure; 758 759 return 0; 760 761 filter_unconfigure: 762 regmap_update_bits(regmap, DFSDM_CR1(adc->fl_id), 763 DFSDM_CR1_CFG_MASK, 0); 764 stop_channels: 765 stm32_dfsdm_stop_channel(indio_dev); 766 767 return ret; 768 } 769 770 static void stm32_dfsdm_stop_conv(struct iio_dev *indio_dev) 771 { 772 struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); 773 struct regmap *regmap = adc->dfsdm->regmap; 774 775 stm32_dfsdm_stop_filter(adc->dfsdm, adc->fl_id); 776 777 regmap_update_bits(regmap, DFSDM_CR1(adc->fl_id), 778 DFSDM_CR1_CFG_MASK, 0); 779 780 stm32_dfsdm_stop_channel(indio_dev); 781 } 782 783 static int stm32_dfsdm_set_watermark(struct iio_dev *indio_dev, 784 unsigned int val) 785 { 786 struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); 787 unsigned int watermark = DFSDM_DMA_BUFFER_SIZE / 2; 788 unsigned int rx_buf_sz = DFSDM_DMA_BUFFER_SIZE; 789 790 /* 791 * DMA cyclic transfers are used, buffer is split into two periods. 792 * There should be : 793 * - always one buffer (period) DMA is working on 794 * - one buffer (period) driver pushed to ASoC side. 795 */ 796 watermark = min(watermark, val * (unsigned int)(sizeof(u32))); 797 adc->buf_sz = min(rx_buf_sz, watermark * 2 * adc->nconv); 798 799 return 0; 800 } 801 802 static unsigned int stm32_dfsdm_adc_dma_residue(struct stm32_dfsdm_adc *adc) 803 { 804 struct dma_tx_state state; 805 enum dma_status status; 806 807 status = dmaengine_tx_status(adc->dma_chan, 808 adc->dma_chan->cookie, 809 &state); 810 if (status == DMA_IN_PROGRESS) { 811 /* Residue is size in bytes from end of buffer */ 812 unsigned int i = adc->buf_sz - state.residue; 813 unsigned int size; 814 815 /* Return available bytes */ 816 if (i >= adc->bufi) 817 size = i - adc->bufi; 818 else 819 size = adc->buf_sz + i - adc->bufi; 820 821 return size; 822 } 823 824 return 0; 825 } 826 827 static inline void stm32_dfsdm_process_data(struct stm32_dfsdm_adc *adc, 828 s32 *buffer) 829 { 830 struct stm32_dfsdm_filter *fl = &adc->dfsdm->fl_list[adc->fl_id]; 831 struct stm32_dfsdm_filter_osr *flo = &fl->flo[fl->fast]; 832 unsigned int i = adc->nconv; 833 s32 *ptr = buffer; 834 835 while (i--) { 836 /* Mask 8 LSB that contains the channel ID */ 837 *ptr &= 0xFFFFFF00; 838 /* Convert 2^(n-1) sample to 2^(n-1)-1 to avoid wrap-around */ 839 if (*ptr > flo->max) 840 *ptr -= 1; 841 /* 842 * Samples from filter are retrieved with 23 bits resolution 843 * or less. Shift left to align MSB on 24 bits. 844 */ 845 *ptr <<= flo->lshift; 846 847 ptr++; 848 } 849 } 850 851 static void stm32_dfsdm_dma_buffer_done(void *data) 852 { 853 struct iio_dev *indio_dev = data; 854 struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); 855 int available = stm32_dfsdm_adc_dma_residue(adc); 856 size_t old_pos; 857 858 /* 859 * FIXME: In Kernel interface does not support cyclic DMA buffer,and 860 * offers only an interface to push data samples per samples. 861 * For this reason IIO buffer interface is not used and interface is 862 * bypassed using a private callback registered by ASoC. 863 * This should be a temporary solution waiting a cyclic DMA engine 864 * support in IIO. 865 */ 866 867 dev_dbg(&indio_dev->dev, "%s: pos = %d, available = %d\n", __func__, 868 adc->bufi, available); 869 old_pos = adc->bufi; 870 871 while (available >= indio_dev->scan_bytes) { 872 s32 *buffer = (s32 *)&adc->rx_buf[adc->bufi]; 873 874 stm32_dfsdm_process_data(adc, buffer); 875 876 available -= indio_dev->scan_bytes; 877 adc->bufi += indio_dev->scan_bytes; 878 if (adc->bufi >= adc->buf_sz) { 879 if (adc->cb) 880 adc->cb(&adc->rx_buf[old_pos], 881 adc->buf_sz - old_pos, adc->cb_priv); 882 adc->bufi = 0; 883 old_pos = 0; 884 } 885 /* 886 * In DMA mode the trigger services of IIO are not used 887 * (e.g. no call to iio_trigger_poll). 888 * Calling irq handler associated to the hardware trigger is not 889 * relevant as the conversions have already been done. Data 890 * transfers are performed directly in DMA callback instead. 891 * This implementation avoids to call trigger irq handler that 892 * may sleep, in an atomic context (DMA irq handler context). 893 */ 894 if (adc->dev_data->type == DFSDM_IIO) 895 iio_push_to_buffers(indio_dev, buffer); 896 } 897 if (adc->cb) 898 adc->cb(&adc->rx_buf[old_pos], adc->bufi - old_pos, 899 adc->cb_priv); 900 } 901 902 static int stm32_dfsdm_adc_dma_start(struct iio_dev *indio_dev) 903 { 904 struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); 905 /* 906 * The DFSDM supports half-word transfers. However, for 16 bits record, 907 * 4 bytes buswidth is kept, to avoid losing samples LSBs when left 908 * shift is required. 909 */ 910 struct dma_slave_config config = { 911 .src_addr = (dma_addr_t)adc->dfsdm->phys_base, 912 .src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES, 913 }; 914 struct dma_async_tx_descriptor *desc; 915 dma_cookie_t cookie; 916 int ret; 917 918 if (!adc->dma_chan) 919 return -EINVAL; 920 921 dev_dbg(&indio_dev->dev, "%s size=%d watermark=%d\n", __func__, 922 adc->buf_sz, adc->buf_sz / 2); 923 924 if (adc->nconv == 1 && !indio_dev->trig) 925 config.src_addr += DFSDM_RDATAR(adc->fl_id); 926 else 927 config.src_addr += DFSDM_JDATAR(adc->fl_id); 928 ret = dmaengine_slave_config(adc->dma_chan, &config); 929 if (ret) 930 return ret; 931 932 /* Prepare a DMA cyclic transaction */ 933 desc = dmaengine_prep_dma_cyclic(adc->dma_chan, 934 adc->dma_buf, 935 adc->buf_sz, adc->buf_sz / 2, 936 DMA_DEV_TO_MEM, 937 DMA_PREP_INTERRUPT); 938 if (!desc) 939 return -EBUSY; 940 941 desc->callback = stm32_dfsdm_dma_buffer_done; 942 desc->callback_param = indio_dev; 943 944 cookie = dmaengine_submit(desc); 945 ret = dma_submit_error(cookie); 946 if (ret) 947 goto err_stop_dma; 948 949 /* Issue pending DMA requests */ 950 dma_async_issue_pending(adc->dma_chan); 951 952 if (adc->nconv == 1 && !indio_dev->trig) { 953 /* Enable regular DMA transfer*/ 954 ret = regmap_update_bits(adc->dfsdm->regmap, 955 DFSDM_CR1(adc->fl_id), 956 DFSDM_CR1_RDMAEN_MASK, 957 DFSDM_CR1_RDMAEN_MASK); 958 } else { 959 /* Enable injected DMA transfer*/ 960 ret = regmap_update_bits(adc->dfsdm->regmap, 961 DFSDM_CR1(adc->fl_id), 962 DFSDM_CR1_JDMAEN_MASK, 963 DFSDM_CR1_JDMAEN_MASK); 964 } 965 966 if (ret < 0) 967 goto err_stop_dma; 968 969 return 0; 970 971 err_stop_dma: 972 dmaengine_terminate_all(adc->dma_chan); 973 974 return ret; 975 } 976 977 static void stm32_dfsdm_adc_dma_stop(struct iio_dev *indio_dev) 978 { 979 struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); 980 981 if (!adc->dma_chan) 982 return; 983 984 regmap_update_bits(adc->dfsdm->regmap, DFSDM_CR1(adc->fl_id), 985 DFSDM_CR1_RDMAEN_MASK | DFSDM_CR1_JDMAEN_MASK, 0); 986 dmaengine_terminate_all(adc->dma_chan); 987 } 988 989 static int stm32_dfsdm_update_scan_mode(struct iio_dev *indio_dev, 990 const unsigned long *scan_mask) 991 { 992 struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); 993 994 adc->nconv = bitmap_weight(scan_mask, indio_dev->masklength); 995 adc->smask = *scan_mask; 996 997 dev_dbg(&indio_dev->dev, "nconv=%d mask=%lx\n", adc->nconv, *scan_mask); 998 999 return 0; 1000 } 1001 1002 static int stm32_dfsdm_postenable(struct iio_dev *indio_dev) 1003 { 1004 struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); 1005 int ret; 1006 1007 /* Reset adc buffer index */ 1008 adc->bufi = 0; 1009 1010 if (adc->hwc) { 1011 ret = iio_hw_consumer_enable(adc->hwc); 1012 if (ret < 0) 1013 return ret; 1014 } 1015 1016 ret = stm32_dfsdm_start_dfsdm(adc->dfsdm); 1017 if (ret < 0) 1018 goto err_stop_hwc; 1019 1020 ret = stm32_dfsdm_adc_dma_start(indio_dev); 1021 if (ret) { 1022 dev_err(&indio_dev->dev, "Can't start DMA\n"); 1023 goto stop_dfsdm; 1024 } 1025 1026 ret = stm32_dfsdm_start_conv(indio_dev, indio_dev->trig); 1027 if (ret) { 1028 dev_err(&indio_dev->dev, "Can't start conversion\n"); 1029 goto err_stop_dma; 1030 } 1031 1032 return 0; 1033 1034 err_stop_dma: 1035 stm32_dfsdm_adc_dma_stop(indio_dev); 1036 stop_dfsdm: 1037 stm32_dfsdm_stop_dfsdm(adc->dfsdm); 1038 err_stop_hwc: 1039 if (adc->hwc) 1040 iio_hw_consumer_disable(adc->hwc); 1041 1042 return ret; 1043 } 1044 1045 static int stm32_dfsdm_predisable(struct iio_dev *indio_dev) 1046 { 1047 struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); 1048 1049 stm32_dfsdm_stop_conv(indio_dev); 1050 1051 stm32_dfsdm_adc_dma_stop(indio_dev); 1052 1053 stm32_dfsdm_stop_dfsdm(adc->dfsdm); 1054 1055 if (adc->hwc) 1056 iio_hw_consumer_disable(adc->hwc); 1057 1058 return 0; 1059 } 1060 1061 static const struct iio_buffer_setup_ops stm32_dfsdm_buffer_setup_ops = { 1062 .postenable = &stm32_dfsdm_postenable, 1063 .predisable = &stm32_dfsdm_predisable, 1064 }; 1065 1066 /** 1067 * stm32_dfsdm_get_buff_cb() - register a callback that will be called when 1068 * DMA transfer period is achieved. 1069 * 1070 * @iio_dev: Handle to IIO device. 1071 * @cb: Pointer to callback function: 1072 * - data: pointer to data buffer 1073 * - size: size in byte of the data buffer 1074 * - private: pointer to consumer private structure. 1075 * @private: Pointer to consumer private structure. 1076 */ 1077 int stm32_dfsdm_get_buff_cb(struct iio_dev *iio_dev, 1078 int (*cb)(const void *data, size_t size, 1079 void *private), 1080 void *private) 1081 { 1082 struct stm32_dfsdm_adc *adc; 1083 1084 if (!iio_dev) 1085 return -EINVAL; 1086 adc = iio_priv(iio_dev); 1087 1088 adc->cb = cb; 1089 adc->cb_priv = private; 1090 1091 return 0; 1092 } 1093 EXPORT_SYMBOL_GPL(stm32_dfsdm_get_buff_cb); 1094 1095 /** 1096 * stm32_dfsdm_release_buff_cb - unregister buffer callback 1097 * 1098 * @iio_dev: Handle to IIO device. 1099 */ 1100 int stm32_dfsdm_release_buff_cb(struct iio_dev *iio_dev) 1101 { 1102 struct stm32_dfsdm_adc *adc; 1103 1104 if (!iio_dev) 1105 return -EINVAL; 1106 adc = iio_priv(iio_dev); 1107 1108 adc->cb = NULL; 1109 adc->cb_priv = NULL; 1110 1111 return 0; 1112 } 1113 EXPORT_SYMBOL_GPL(stm32_dfsdm_release_buff_cb); 1114 1115 static int stm32_dfsdm_single_conv(struct iio_dev *indio_dev, 1116 const struct iio_chan_spec *chan, int *res) 1117 { 1118 struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); 1119 long timeout; 1120 int ret; 1121 1122 reinit_completion(&adc->completion); 1123 1124 adc->buffer = res; 1125 1126 ret = stm32_dfsdm_start_dfsdm(adc->dfsdm); 1127 if (ret < 0) 1128 return ret; 1129 1130 ret = regmap_update_bits(adc->dfsdm->regmap, DFSDM_CR2(adc->fl_id), 1131 DFSDM_CR2_REOCIE_MASK, DFSDM_CR2_REOCIE(1)); 1132 if (ret < 0) 1133 goto stop_dfsdm; 1134 1135 adc->nconv = 1; 1136 adc->smask = BIT(chan->scan_index); 1137 ret = stm32_dfsdm_start_conv(indio_dev, NULL); 1138 if (ret < 0) { 1139 regmap_update_bits(adc->dfsdm->regmap, DFSDM_CR2(adc->fl_id), 1140 DFSDM_CR2_REOCIE_MASK, DFSDM_CR2_REOCIE(0)); 1141 goto stop_dfsdm; 1142 } 1143 1144 timeout = wait_for_completion_interruptible_timeout(&adc->completion, 1145 DFSDM_TIMEOUT); 1146 1147 /* Mask IRQ for regular conversion achievement*/ 1148 regmap_update_bits(adc->dfsdm->regmap, DFSDM_CR2(adc->fl_id), 1149 DFSDM_CR2_REOCIE_MASK, DFSDM_CR2_REOCIE(0)); 1150 1151 if (timeout == 0) 1152 ret = -ETIMEDOUT; 1153 else if (timeout < 0) 1154 ret = timeout; 1155 else 1156 ret = IIO_VAL_INT; 1157 1158 stm32_dfsdm_stop_conv(indio_dev); 1159 1160 stm32_dfsdm_process_data(adc, res); 1161 1162 stop_dfsdm: 1163 stm32_dfsdm_stop_dfsdm(adc->dfsdm); 1164 1165 return ret; 1166 } 1167 1168 static int stm32_dfsdm_write_raw(struct iio_dev *indio_dev, 1169 struct iio_chan_spec const *chan, 1170 int val, int val2, long mask) 1171 { 1172 struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); 1173 struct stm32_dfsdm_channel *ch = &adc->dfsdm->ch_list[chan->channel]; 1174 unsigned int spi_freq; 1175 int ret = -EINVAL; 1176 1177 switch (ch->src) { 1178 case DFSDM_CHANNEL_SPI_CLOCK_INTERNAL: 1179 spi_freq = adc->dfsdm->spi_master_freq; 1180 break; 1181 case DFSDM_CHANNEL_SPI_CLOCK_INTERNAL_DIV2_FALLING: 1182 case DFSDM_CHANNEL_SPI_CLOCK_INTERNAL_DIV2_RISING: 1183 spi_freq = adc->dfsdm->spi_master_freq / 2; 1184 break; 1185 default: 1186 spi_freq = adc->spi_freq; 1187 } 1188 1189 switch (mask) { 1190 case IIO_CHAN_INFO_OVERSAMPLING_RATIO: 1191 ret = iio_device_claim_direct_mode(indio_dev); 1192 if (ret) 1193 return ret; 1194 1195 ret = stm32_dfsdm_compute_all_osrs(indio_dev, val); 1196 if (!ret) { 1197 dev_dbg(&indio_dev->dev, 1198 "Sampling rate changed from (%u) to (%u)\n", 1199 adc->sample_freq, spi_freq / val); 1200 adc->oversamp = val; 1201 adc->sample_freq = spi_freq / val; 1202 } 1203 iio_device_release_direct_mode(indio_dev); 1204 return ret; 1205 1206 case IIO_CHAN_INFO_SAMP_FREQ: 1207 if (!val) 1208 return -EINVAL; 1209 1210 ret = iio_device_claim_direct_mode(indio_dev); 1211 if (ret) 1212 return ret; 1213 1214 ret = dfsdm_adc_set_samp_freq(indio_dev, val, spi_freq); 1215 iio_device_release_direct_mode(indio_dev); 1216 return ret; 1217 } 1218 1219 return -EINVAL; 1220 } 1221 1222 static int stm32_dfsdm_read_raw(struct iio_dev *indio_dev, 1223 struct iio_chan_spec const *chan, int *val, 1224 int *val2, long mask) 1225 { 1226 struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); 1227 int ret; 1228 1229 switch (mask) { 1230 case IIO_CHAN_INFO_RAW: 1231 ret = iio_device_claim_direct_mode(indio_dev); 1232 if (ret) 1233 return ret; 1234 ret = iio_hw_consumer_enable(adc->hwc); 1235 if (ret < 0) { 1236 dev_err(&indio_dev->dev, 1237 "%s: IIO enable failed (channel %d)\n", 1238 __func__, chan->channel); 1239 iio_device_release_direct_mode(indio_dev); 1240 return ret; 1241 } 1242 ret = stm32_dfsdm_single_conv(indio_dev, chan, val); 1243 iio_hw_consumer_disable(adc->hwc); 1244 if (ret < 0) { 1245 dev_err(&indio_dev->dev, 1246 "%s: Conversion failed (channel %d)\n", 1247 __func__, chan->channel); 1248 iio_device_release_direct_mode(indio_dev); 1249 return ret; 1250 } 1251 iio_device_release_direct_mode(indio_dev); 1252 return IIO_VAL_INT; 1253 1254 case IIO_CHAN_INFO_OVERSAMPLING_RATIO: 1255 *val = adc->oversamp; 1256 1257 return IIO_VAL_INT; 1258 1259 case IIO_CHAN_INFO_SAMP_FREQ: 1260 *val = adc->sample_freq; 1261 1262 return IIO_VAL_INT; 1263 } 1264 1265 return -EINVAL; 1266 } 1267 1268 static int stm32_dfsdm_validate_trigger(struct iio_dev *indio_dev, 1269 struct iio_trigger *trig) 1270 { 1271 return stm32_dfsdm_get_jextsel(indio_dev, trig) < 0 ? -EINVAL : 0; 1272 } 1273 1274 static const struct iio_info stm32_dfsdm_info_audio = { 1275 .hwfifo_set_watermark = stm32_dfsdm_set_watermark, 1276 .read_raw = stm32_dfsdm_read_raw, 1277 .write_raw = stm32_dfsdm_write_raw, 1278 .update_scan_mode = stm32_dfsdm_update_scan_mode, 1279 }; 1280 1281 static const struct iio_info stm32_dfsdm_info_adc = { 1282 .hwfifo_set_watermark = stm32_dfsdm_set_watermark, 1283 .read_raw = stm32_dfsdm_read_raw, 1284 .write_raw = stm32_dfsdm_write_raw, 1285 .update_scan_mode = stm32_dfsdm_update_scan_mode, 1286 .validate_trigger = stm32_dfsdm_validate_trigger, 1287 }; 1288 1289 static irqreturn_t stm32_dfsdm_irq(int irq, void *arg) 1290 { 1291 struct iio_dev *indio_dev = arg; 1292 struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); 1293 struct regmap *regmap = adc->dfsdm->regmap; 1294 unsigned int status, int_en; 1295 1296 regmap_read(regmap, DFSDM_ISR(adc->fl_id), &status); 1297 regmap_read(regmap, DFSDM_CR2(adc->fl_id), &int_en); 1298 1299 if (status & DFSDM_ISR_REOCF_MASK) { 1300 /* Read the data register clean the IRQ status */ 1301 regmap_read(regmap, DFSDM_RDATAR(adc->fl_id), adc->buffer); 1302 complete(&adc->completion); 1303 } 1304 1305 if (status & DFSDM_ISR_ROVRF_MASK) { 1306 if (int_en & DFSDM_CR2_ROVRIE_MASK) 1307 dev_warn(&indio_dev->dev, "Overrun detected\n"); 1308 regmap_update_bits(regmap, DFSDM_ICR(adc->fl_id), 1309 DFSDM_ICR_CLRROVRF_MASK, 1310 DFSDM_ICR_CLRROVRF_MASK); 1311 } 1312 1313 return IRQ_HANDLED; 1314 } 1315 1316 /* 1317 * Define external info for SPI Frequency and audio sampling rate that can be 1318 * configured by ASoC driver through consumer.h API 1319 */ 1320 static const struct iio_chan_spec_ext_info dfsdm_adc_audio_ext_info[] = { 1321 /* spi_clk_freq : clock freq on SPI/manchester bus used by channel */ 1322 { 1323 .name = "spi_clk_freq", 1324 .shared = IIO_SHARED_BY_TYPE, 1325 .read = dfsdm_adc_audio_get_spiclk, 1326 .write = dfsdm_adc_audio_set_spiclk, 1327 }, 1328 {}, 1329 }; 1330 1331 static void stm32_dfsdm_dma_release(struct iio_dev *indio_dev) 1332 { 1333 struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); 1334 1335 if (adc->dma_chan) { 1336 dma_free_coherent(adc->dma_chan->device->dev, 1337 DFSDM_DMA_BUFFER_SIZE, 1338 adc->rx_buf, adc->dma_buf); 1339 dma_release_channel(adc->dma_chan); 1340 } 1341 } 1342 1343 static int stm32_dfsdm_dma_request(struct device *dev, 1344 struct iio_dev *indio_dev) 1345 { 1346 struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); 1347 1348 adc->dma_chan = dma_request_chan(dev, "rx"); 1349 if (IS_ERR(adc->dma_chan)) { 1350 int ret = PTR_ERR(adc->dma_chan); 1351 1352 adc->dma_chan = NULL; 1353 return ret; 1354 } 1355 1356 adc->rx_buf = dma_alloc_coherent(adc->dma_chan->device->dev, 1357 DFSDM_DMA_BUFFER_SIZE, 1358 &adc->dma_buf, GFP_KERNEL); 1359 if (!adc->rx_buf) { 1360 dma_release_channel(adc->dma_chan); 1361 return -ENOMEM; 1362 } 1363 1364 indio_dev->modes |= INDIO_BUFFER_SOFTWARE; 1365 indio_dev->setup_ops = &stm32_dfsdm_buffer_setup_ops; 1366 1367 return 0; 1368 } 1369 1370 static int stm32_dfsdm_adc_chan_init_one(struct iio_dev *indio_dev, 1371 struct iio_chan_spec *ch) 1372 { 1373 struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); 1374 int ret; 1375 1376 ret = stm32_dfsdm_channel_parse_of(adc->dfsdm, indio_dev, ch); 1377 if (ret < 0) 1378 return ret; 1379 1380 ch->type = IIO_VOLTAGE; 1381 ch->indexed = 1; 1382 1383 /* 1384 * IIO_CHAN_INFO_RAW: used to compute regular conversion 1385 * IIO_CHAN_INFO_OVERSAMPLING_RATIO: used to set oversampling 1386 */ 1387 ch->info_mask_separate = BIT(IIO_CHAN_INFO_RAW); 1388 ch->info_mask_shared_by_all = BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO) | 1389 BIT(IIO_CHAN_INFO_SAMP_FREQ); 1390 1391 if (adc->dev_data->type == DFSDM_AUDIO) { 1392 ch->ext_info = dfsdm_adc_audio_ext_info; 1393 } else { 1394 ch->scan_type.shift = 8; 1395 } 1396 ch->scan_type.sign = 's'; 1397 ch->scan_type.realbits = 24; 1398 ch->scan_type.storagebits = 32; 1399 1400 return stm32_dfsdm_chan_configure(adc->dfsdm, 1401 &adc->dfsdm->ch_list[ch->channel]); 1402 } 1403 1404 static int stm32_dfsdm_audio_init(struct device *dev, struct iio_dev *indio_dev) 1405 { 1406 struct iio_chan_spec *ch; 1407 struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); 1408 struct stm32_dfsdm_channel *d_ch; 1409 int ret; 1410 1411 ch = devm_kzalloc(&indio_dev->dev, sizeof(*ch), GFP_KERNEL); 1412 if (!ch) 1413 return -ENOMEM; 1414 1415 ch->scan_index = 0; 1416 1417 ret = stm32_dfsdm_adc_chan_init_one(indio_dev, ch); 1418 if (ret < 0) { 1419 dev_err(&indio_dev->dev, "Channels init failed\n"); 1420 return ret; 1421 } 1422 ch->info_mask_separate = BIT(IIO_CHAN_INFO_SAMP_FREQ); 1423 1424 d_ch = &adc->dfsdm->ch_list[ch->channel]; 1425 if (d_ch->src != DFSDM_CHANNEL_SPI_CLOCK_EXTERNAL) 1426 adc->spi_freq = adc->dfsdm->spi_master_freq; 1427 1428 indio_dev->num_channels = 1; 1429 indio_dev->channels = ch; 1430 1431 return stm32_dfsdm_dma_request(dev, indio_dev); 1432 } 1433 1434 static int stm32_dfsdm_adc_init(struct device *dev, struct iio_dev *indio_dev) 1435 { 1436 struct iio_chan_spec *ch; 1437 struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); 1438 int num_ch; 1439 int ret, chan_idx; 1440 1441 adc->oversamp = DFSDM_DEFAULT_OVERSAMPLING; 1442 ret = stm32_dfsdm_compute_all_osrs(indio_dev, adc->oversamp); 1443 if (ret < 0) 1444 return ret; 1445 1446 num_ch = of_property_count_u32_elems(indio_dev->dev.of_node, 1447 "st,adc-channels"); 1448 if (num_ch < 0 || num_ch > adc->dfsdm->num_chs) { 1449 dev_err(&indio_dev->dev, "Bad st,adc-channels\n"); 1450 return num_ch < 0 ? num_ch : -EINVAL; 1451 } 1452 1453 /* Bind to SD modulator IIO device */ 1454 adc->hwc = devm_iio_hw_consumer_alloc(&indio_dev->dev); 1455 if (IS_ERR(adc->hwc)) 1456 return -EPROBE_DEFER; 1457 1458 ch = devm_kcalloc(&indio_dev->dev, num_ch, sizeof(*ch), 1459 GFP_KERNEL); 1460 if (!ch) 1461 return -ENOMEM; 1462 1463 for (chan_idx = 0; chan_idx < num_ch; chan_idx++) { 1464 ch[chan_idx].scan_index = chan_idx; 1465 ret = stm32_dfsdm_adc_chan_init_one(indio_dev, &ch[chan_idx]); 1466 if (ret < 0) { 1467 dev_err(&indio_dev->dev, "Channels init failed\n"); 1468 return ret; 1469 } 1470 } 1471 1472 indio_dev->num_channels = num_ch; 1473 indio_dev->channels = ch; 1474 1475 init_completion(&adc->completion); 1476 1477 /* Optionally request DMA */ 1478 ret = stm32_dfsdm_dma_request(dev, indio_dev); 1479 if (ret) { 1480 if (ret != -ENODEV) 1481 return dev_err_probe(dev, ret, 1482 "DMA channel request failed with\n"); 1483 1484 dev_dbg(dev, "No DMA support\n"); 1485 return 0; 1486 } 1487 1488 ret = iio_triggered_buffer_setup(indio_dev, 1489 &iio_pollfunc_store_time, NULL, 1490 &stm32_dfsdm_buffer_setup_ops); 1491 if (ret) { 1492 stm32_dfsdm_dma_release(indio_dev); 1493 dev_err(&indio_dev->dev, "buffer setup failed\n"); 1494 return ret; 1495 } 1496 1497 /* lptimer/timer hardware triggers */ 1498 indio_dev->modes |= INDIO_HARDWARE_TRIGGERED; 1499 1500 return 0; 1501 } 1502 1503 static const struct stm32_dfsdm_dev_data stm32h7_dfsdm_adc_data = { 1504 .type = DFSDM_IIO, 1505 .init = stm32_dfsdm_adc_init, 1506 }; 1507 1508 static const struct stm32_dfsdm_dev_data stm32h7_dfsdm_audio_data = { 1509 .type = DFSDM_AUDIO, 1510 .init = stm32_dfsdm_audio_init, 1511 }; 1512 1513 static const struct of_device_id stm32_dfsdm_adc_match[] = { 1514 { 1515 .compatible = "st,stm32-dfsdm-adc", 1516 .data = &stm32h7_dfsdm_adc_data, 1517 }, 1518 { 1519 .compatible = "st,stm32-dfsdm-dmic", 1520 .data = &stm32h7_dfsdm_audio_data, 1521 }, 1522 {} 1523 }; 1524 1525 static int stm32_dfsdm_adc_probe(struct platform_device *pdev) 1526 { 1527 struct device *dev = &pdev->dev; 1528 struct stm32_dfsdm_adc *adc; 1529 struct device_node *np = dev->of_node; 1530 const struct stm32_dfsdm_dev_data *dev_data; 1531 struct iio_dev *iio; 1532 char *name; 1533 int ret, irq, val; 1534 1535 dev_data = of_device_get_match_data(dev); 1536 iio = devm_iio_device_alloc(dev, sizeof(*adc)); 1537 if (!iio) { 1538 dev_err(dev, "%s: Failed to allocate IIO\n", __func__); 1539 return -ENOMEM; 1540 } 1541 1542 adc = iio_priv(iio); 1543 adc->dfsdm = dev_get_drvdata(dev->parent); 1544 1545 iio->dev.of_node = np; 1546 iio->modes = INDIO_DIRECT_MODE; 1547 1548 platform_set_drvdata(pdev, iio); 1549 1550 ret = of_property_read_u32(dev->of_node, "reg", &adc->fl_id); 1551 if (ret != 0 || adc->fl_id >= adc->dfsdm->num_fls) { 1552 dev_err(dev, "Missing or bad reg property\n"); 1553 return -EINVAL; 1554 } 1555 1556 name = devm_kzalloc(dev, sizeof("dfsdm-adc0"), GFP_KERNEL); 1557 if (!name) 1558 return -ENOMEM; 1559 if (dev_data->type == DFSDM_AUDIO) { 1560 iio->info = &stm32_dfsdm_info_audio; 1561 snprintf(name, sizeof("dfsdm-pdm0"), "dfsdm-pdm%d", adc->fl_id); 1562 } else { 1563 iio->info = &stm32_dfsdm_info_adc; 1564 snprintf(name, sizeof("dfsdm-adc0"), "dfsdm-adc%d", adc->fl_id); 1565 } 1566 iio->name = name; 1567 1568 /* 1569 * In a first step IRQs generated for channels are not treated. 1570 * So IRQ associated to filter instance 0 is dedicated to the Filter 0. 1571 */ 1572 irq = platform_get_irq(pdev, 0); 1573 if (irq < 0) 1574 return irq; 1575 1576 ret = devm_request_irq(dev, irq, stm32_dfsdm_irq, 1577 0, pdev->name, iio); 1578 if (ret < 0) { 1579 dev_err(dev, "Failed to request IRQ\n"); 1580 return ret; 1581 } 1582 1583 ret = of_property_read_u32(dev->of_node, "st,filter-order", &val); 1584 if (ret < 0) { 1585 dev_err(dev, "Failed to set filter order\n"); 1586 return ret; 1587 } 1588 1589 adc->dfsdm->fl_list[adc->fl_id].ford = val; 1590 1591 ret = of_property_read_u32(dev->of_node, "st,filter0-sync", &val); 1592 if (!ret) 1593 adc->dfsdm->fl_list[adc->fl_id].sync_mode = val; 1594 1595 adc->dev_data = dev_data; 1596 ret = dev_data->init(dev, iio); 1597 if (ret < 0) 1598 return ret; 1599 1600 ret = iio_device_register(iio); 1601 if (ret < 0) 1602 goto err_cleanup; 1603 1604 if (dev_data->type == DFSDM_AUDIO) { 1605 ret = of_platform_populate(np, NULL, NULL, dev); 1606 if (ret < 0) { 1607 dev_err(dev, "Failed to find an audio DAI\n"); 1608 goto err_unregister; 1609 } 1610 } 1611 1612 return 0; 1613 1614 err_unregister: 1615 iio_device_unregister(iio); 1616 err_cleanup: 1617 stm32_dfsdm_dma_release(iio); 1618 1619 return ret; 1620 } 1621 1622 static int stm32_dfsdm_adc_remove(struct platform_device *pdev) 1623 { 1624 struct iio_dev *indio_dev = platform_get_drvdata(pdev); 1625 struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); 1626 1627 if (adc->dev_data->type == DFSDM_AUDIO) 1628 of_platform_depopulate(&pdev->dev); 1629 iio_device_unregister(indio_dev); 1630 stm32_dfsdm_dma_release(indio_dev); 1631 1632 return 0; 1633 } 1634 1635 static int __maybe_unused stm32_dfsdm_adc_suspend(struct device *dev) 1636 { 1637 struct iio_dev *indio_dev = dev_get_drvdata(dev); 1638 1639 if (iio_buffer_enabled(indio_dev)) 1640 stm32_dfsdm_predisable(indio_dev); 1641 1642 return 0; 1643 } 1644 1645 static int __maybe_unused stm32_dfsdm_adc_resume(struct device *dev) 1646 { 1647 struct iio_dev *indio_dev = dev_get_drvdata(dev); 1648 struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); 1649 const struct iio_chan_spec *chan; 1650 struct stm32_dfsdm_channel *ch; 1651 int i, ret; 1652 1653 /* restore channels configuration */ 1654 for (i = 0; i < indio_dev->num_channels; i++) { 1655 chan = indio_dev->channels + i; 1656 ch = &adc->dfsdm->ch_list[chan->channel]; 1657 ret = stm32_dfsdm_chan_configure(adc->dfsdm, ch); 1658 if (ret) 1659 return ret; 1660 } 1661 1662 if (iio_buffer_enabled(indio_dev)) 1663 stm32_dfsdm_postenable(indio_dev); 1664 1665 return 0; 1666 } 1667 1668 static SIMPLE_DEV_PM_OPS(stm32_dfsdm_adc_pm_ops, 1669 stm32_dfsdm_adc_suspend, stm32_dfsdm_adc_resume); 1670 1671 static struct platform_driver stm32_dfsdm_adc_driver = { 1672 .driver = { 1673 .name = "stm32-dfsdm-adc", 1674 .of_match_table = stm32_dfsdm_adc_match, 1675 .pm = &stm32_dfsdm_adc_pm_ops, 1676 }, 1677 .probe = stm32_dfsdm_adc_probe, 1678 .remove = stm32_dfsdm_adc_remove, 1679 }; 1680 module_platform_driver(stm32_dfsdm_adc_driver); 1681 1682 MODULE_DESCRIPTION("STM32 sigma delta ADC"); 1683 MODULE_AUTHOR("Arnaud Pouliquen <arnaud.pouliquen@st.com>"); 1684 MODULE_LICENSE("GPL v2"); 1685