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; 296 297 pr_debug("%s: fast %d, fosr %d, iosr %d, res 0x%llx/%d bits, rshift %d, lshift %d\n", 298 __func__, fast, flo->fosr, flo->iosr, 299 flo->res, bits, flo->rshift, 300 flo->lshift); 301 } 302 } 303 } 304 305 if (!flo->res) 306 return -EINVAL; 307 308 return 0; 309 } 310 311 static int stm32_dfsdm_compute_all_osrs(struct iio_dev *indio_dev, 312 unsigned int oversamp) 313 { 314 struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); 315 struct stm32_dfsdm_filter *fl = &adc->dfsdm->fl_list[adc->fl_id]; 316 int ret0, ret1; 317 318 memset(&fl->flo[0], 0, sizeof(fl->flo[0])); 319 memset(&fl->flo[1], 0, sizeof(fl->flo[1])); 320 321 ret0 = stm32_dfsdm_compute_osrs(fl, 0, oversamp); 322 ret1 = stm32_dfsdm_compute_osrs(fl, 1, oversamp); 323 if (ret0 < 0 && ret1 < 0) { 324 dev_err(&indio_dev->dev, 325 "Filter parameters not found: errors %d/%d\n", 326 ret0, ret1); 327 return -EINVAL; 328 } 329 330 return 0; 331 } 332 333 static int stm32_dfsdm_start_channel(struct iio_dev *indio_dev) 334 { 335 struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); 336 struct regmap *regmap = adc->dfsdm->regmap; 337 const struct iio_chan_spec *chan; 338 unsigned int bit; 339 int ret; 340 341 for_each_set_bit(bit, &adc->smask, sizeof(adc->smask) * BITS_PER_BYTE) { 342 chan = indio_dev->channels + bit; 343 ret = regmap_update_bits(regmap, DFSDM_CHCFGR1(chan->channel), 344 DFSDM_CHCFGR1_CHEN_MASK, 345 DFSDM_CHCFGR1_CHEN(1)); 346 if (ret < 0) 347 return ret; 348 } 349 350 return 0; 351 } 352 353 static void stm32_dfsdm_stop_channel(struct iio_dev *indio_dev) 354 { 355 struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); 356 struct regmap *regmap = adc->dfsdm->regmap; 357 const struct iio_chan_spec *chan; 358 unsigned int bit; 359 360 for_each_set_bit(bit, &adc->smask, sizeof(adc->smask) * BITS_PER_BYTE) { 361 chan = indio_dev->channels + bit; 362 regmap_update_bits(regmap, DFSDM_CHCFGR1(chan->channel), 363 DFSDM_CHCFGR1_CHEN_MASK, 364 DFSDM_CHCFGR1_CHEN(0)); 365 } 366 } 367 368 static int stm32_dfsdm_chan_configure(struct stm32_dfsdm *dfsdm, 369 struct stm32_dfsdm_channel *ch) 370 { 371 unsigned int id = ch->id; 372 struct regmap *regmap = dfsdm->regmap; 373 int ret; 374 375 ret = regmap_update_bits(regmap, DFSDM_CHCFGR1(id), 376 DFSDM_CHCFGR1_SITP_MASK, 377 DFSDM_CHCFGR1_SITP(ch->type)); 378 if (ret < 0) 379 return ret; 380 ret = regmap_update_bits(regmap, DFSDM_CHCFGR1(id), 381 DFSDM_CHCFGR1_SPICKSEL_MASK, 382 DFSDM_CHCFGR1_SPICKSEL(ch->src)); 383 if (ret < 0) 384 return ret; 385 return regmap_update_bits(regmap, DFSDM_CHCFGR1(id), 386 DFSDM_CHCFGR1_CHINSEL_MASK, 387 DFSDM_CHCFGR1_CHINSEL(ch->alt_si)); 388 } 389 390 static int stm32_dfsdm_start_filter(struct stm32_dfsdm_adc *adc, 391 unsigned int fl_id, 392 struct iio_trigger *trig) 393 { 394 struct stm32_dfsdm *dfsdm = adc->dfsdm; 395 int ret; 396 397 /* Enable filter */ 398 ret = regmap_update_bits(dfsdm->regmap, DFSDM_CR1(fl_id), 399 DFSDM_CR1_DFEN_MASK, DFSDM_CR1_DFEN(1)); 400 if (ret < 0) 401 return ret; 402 403 /* Nothing more to do for injected (scan mode/triggered) conversions */ 404 if (adc->nconv > 1 || trig) 405 return 0; 406 407 /* Software start (single or continuous) regular conversion */ 408 return regmap_update_bits(dfsdm->regmap, DFSDM_CR1(fl_id), 409 DFSDM_CR1_RSWSTART_MASK, 410 DFSDM_CR1_RSWSTART(1)); 411 } 412 413 static void stm32_dfsdm_stop_filter(struct stm32_dfsdm *dfsdm, 414 unsigned int fl_id) 415 { 416 /* Disable conversion */ 417 regmap_update_bits(dfsdm->regmap, DFSDM_CR1(fl_id), 418 DFSDM_CR1_DFEN_MASK, DFSDM_CR1_DFEN(0)); 419 } 420 421 static int stm32_dfsdm_filter_set_trig(struct iio_dev *indio_dev, 422 unsigned int fl_id, 423 struct iio_trigger *trig) 424 { 425 struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); 426 struct regmap *regmap = adc->dfsdm->regmap; 427 u32 jextsel = 0, jexten = STM32_DFSDM_JEXTEN_DISABLED; 428 int ret; 429 430 if (trig) { 431 ret = stm32_dfsdm_get_jextsel(indio_dev, trig); 432 if (ret < 0) 433 return ret; 434 435 /* set trigger source and polarity (default to rising edge) */ 436 jextsel = ret; 437 jexten = STM32_DFSDM_JEXTEN_RISING_EDGE; 438 } 439 440 ret = regmap_update_bits(regmap, DFSDM_CR1(fl_id), 441 DFSDM_CR1_JEXTSEL_MASK | DFSDM_CR1_JEXTEN_MASK, 442 DFSDM_CR1_JEXTSEL(jextsel) | 443 DFSDM_CR1_JEXTEN(jexten)); 444 if (ret < 0) 445 return ret; 446 447 return 0; 448 } 449 450 static int stm32_dfsdm_channels_configure(struct iio_dev *indio_dev, 451 unsigned int fl_id, 452 struct iio_trigger *trig) 453 { 454 struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); 455 struct regmap *regmap = adc->dfsdm->regmap; 456 struct stm32_dfsdm_filter *fl = &adc->dfsdm->fl_list[fl_id]; 457 struct stm32_dfsdm_filter_osr *flo = &fl->flo[0]; 458 const struct iio_chan_spec *chan; 459 unsigned int bit; 460 int ret; 461 462 fl->fast = 0; 463 464 /* 465 * In continuous mode, use fast mode configuration, 466 * if it provides a better resolution. 467 */ 468 if (adc->nconv == 1 && !trig && 469 (indio_dev->currentmode & INDIO_BUFFER_SOFTWARE)) { 470 if (fl->flo[1].res >= fl->flo[0].res) { 471 fl->fast = 1; 472 flo = &fl->flo[1]; 473 } 474 } 475 476 if (!flo->res) 477 return -EINVAL; 478 479 for_each_set_bit(bit, &adc->smask, 480 sizeof(adc->smask) * BITS_PER_BYTE) { 481 chan = indio_dev->channels + bit; 482 483 ret = regmap_update_bits(regmap, 484 DFSDM_CHCFGR2(chan->channel), 485 DFSDM_CHCFGR2_DTRBS_MASK, 486 DFSDM_CHCFGR2_DTRBS(flo->rshift)); 487 if (ret) 488 return ret; 489 } 490 491 return 0; 492 } 493 494 static int stm32_dfsdm_filter_configure(struct iio_dev *indio_dev, 495 unsigned int fl_id, 496 struct iio_trigger *trig) 497 { 498 struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); 499 struct regmap *regmap = adc->dfsdm->regmap; 500 struct stm32_dfsdm_filter *fl = &adc->dfsdm->fl_list[fl_id]; 501 struct stm32_dfsdm_filter_osr *flo = &fl->flo[fl->fast]; 502 u32 cr1; 503 const struct iio_chan_spec *chan; 504 unsigned int bit, jchg = 0; 505 int ret; 506 507 /* Average integrator oversampling */ 508 ret = regmap_update_bits(regmap, DFSDM_FCR(fl_id), DFSDM_FCR_IOSR_MASK, 509 DFSDM_FCR_IOSR(flo->iosr - 1)); 510 if (ret) 511 return ret; 512 513 /* Filter order and Oversampling */ 514 ret = regmap_update_bits(regmap, DFSDM_FCR(fl_id), DFSDM_FCR_FOSR_MASK, 515 DFSDM_FCR_FOSR(flo->fosr - 1)); 516 if (ret) 517 return ret; 518 519 ret = regmap_update_bits(regmap, DFSDM_FCR(fl_id), DFSDM_FCR_FORD_MASK, 520 DFSDM_FCR_FORD(fl->ford)); 521 if (ret) 522 return ret; 523 524 ret = stm32_dfsdm_filter_set_trig(indio_dev, fl_id, trig); 525 if (ret) 526 return ret; 527 528 ret = regmap_update_bits(regmap, DFSDM_CR1(fl_id), 529 DFSDM_CR1_FAST_MASK, 530 DFSDM_CR1_FAST(fl->fast)); 531 if (ret) 532 return ret; 533 534 /* 535 * DFSDM modes configuration W.R.T audio/iio type modes 536 * ---------------------------------------------------------------- 537 * Modes | regular | regular | injected | injected | 538 * | | continuous | | + scan | 539 * --------------|---------|--------------|----------|------------| 540 * single conv | x | | | | 541 * (1 chan) | | | | | 542 * --------------|---------|--------------|----------|------------| 543 * 1 Audio chan | | sample freq | | | 544 * | | or sync_mode | | | 545 * --------------|---------|--------------|----------|------------| 546 * 1 IIO chan | | sample freq | trigger | | 547 * | | or sync_mode | | | 548 * --------------|---------|--------------|----------|------------| 549 * 2+ IIO chans | | | | trigger or | 550 * | | | | sync_mode | 551 * ---------------------------------------------------------------- 552 */ 553 if (adc->nconv == 1 && !trig) { 554 bit = __ffs(adc->smask); 555 chan = indio_dev->channels + bit; 556 557 /* Use regular conversion for single channel without trigger */ 558 cr1 = DFSDM_CR1_RCH(chan->channel); 559 560 /* Continuous conversions triggered by SPI clk in buffer mode */ 561 if (indio_dev->currentmode & INDIO_BUFFER_SOFTWARE) 562 cr1 |= DFSDM_CR1_RCONT(1); 563 564 cr1 |= DFSDM_CR1_RSYNC(fl->sync_mode); 565 } else { 566 /* Use injected conversion for multiple channels */ 567 for_each_set_bit(bit, &adc->smask, 568 sizeof(adc->smask) * BITS_PER_BYTE) { 569 chan = indio_dev->channels + bit; 570 jchg |= BIT(chan->channel); 571 } 572 ret = regmap_write(regmap, DFSDM_JCHGR(fl_id), jchg); 573 if (ret < 0) 574 return ret; 575 576 /* Use scan mode for multiple channels */ 577 cr1 = DFSDM_CR1_JSCAN((adc->nconv > 1) ? 1 : 0); 578 579 /* 580 * Continuous conversions not supported in injected mode, 581 * either use: 582 * - conversions in sync with filter 0 583 * - triggered conversions 584 */ 585 if (!fl->sync_mode && !trig) 586 return -EINVAL; 587 cr1 |= DFSDM_CR1_JSYNC(fl->sync_mode); 588 } 589 590 return regmap_update_bits(regmap, DFSDM_CR1(fl_id), DFSDM_CR1_CFG_MASK, 591 cr1); 592 } 593 594 static int stm32_dfsdm_channel_parse_of(struct stm32_dfsdm *dfsdm, 595 struct iio_dev *indio_dev, 596 struct iio_chan_spec *ch) 597 { 598 struct stm32_dfsdm_channel *df_ch; 599 const char *of_str; 600 int chan_idx = ch->scan_index; 601 int ret, val; 602 603 ret = of_property_read_u32_index(indio_dev->dev.of_node, 604 "st,adc-channels", chan_idx, 605 &ch->channel); 606 if (ret < 0) { 607 dev_err(&indio_dev->dev, 608 " Error parsing 'st,adc-channels' for idx %d\n", 609 chan_idx); 610 return ret; 611 } 612 if (ch->channel >= dfsdm->num_chs) { 613 dev_err(&indio_dev->dev, 614 " Error bad channel number %d (max = %d)\n", 615 ch->channel, dfsdm->num_chs); 616 return -EINVAL; 617 } 618 619 ret = of_property_read_string_index(indio_dev->dev.of_node, 620 "st,adc-channel-names", chan_idx, 621 &ch->datasheet_name); 622 if (ret < 0) { 623 dev_err(&indio_dev->dev, 624 " Error parsing 'st,adc-channel-names' for idx %d\n", 625 chan_idx); 626 return ret; 627 } 628 629 df_ch = &dfsdm->ch_list[ch->channel]; 630 df_ch->id = ch->channel; 631 632 ret = of_property_read_string_index(indio_dev->dev.of_node, 633 "st,adc-channel-types", chan_idx, 634 &of_str); 635 if (!ret) { 636 val = stm32_dfsdm_str2val(of_str, stm32_dfsdm_chan_type); 637 if (val < 0) 638 return val; 639 } else { 640 val = 0; 641 } 642 df_ch->type = val; 643 644 ret = of_property_read_string_index(indio_dev->dev.of_node, 645 "st,adc-channel-clk-src", chan_idx, 646 &of_str); 647 if (!ret) { 648 val = stm32_dfsdm_str2val(of_str, stm32_dfsdm_chan_src); 649 if (val < 0) 650 return val; 651 } else { 652 val = 0; 653 } 654 df_ch->src = val; 655 656 ret = of_property_read_u32_index(indio_dev->dev.of_node, 657 "st,adc-alt-channel", chan_idx, 658 &df_ch->alt_si); 659 if (ret < 0) 660 df_ch->alt_si = 0; 661 662 return 0; 663 } 664 665 static ssize_t dfsdm_adc_audio_get_spiclk(struct iio_dev *indio_dev, 666 uintptr_t priv, 667 const struct iio_chan_spec *chan, 668 char *buf) 669 { 670 struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); 671 672 return snprintf(buf, PAGE_SIZE, "%d\n", adc->spi_freq); 673 } 674 675 static int dfsdm_adc_set_samp_freq(struct iio_dev *indio_dev, 676 unsigned int sample_freq, 677 unsigned int spi_freq) 678 { 679 struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); 680 unsigned int oversamp; 681 int ret; 682 683 oversamp = DIV_ROUND_CLOSEST(spi_freq, sample_freq); 684 if (spi_freq % sample_freq) 685 dev_dbg(&indio_dev->dev, 686 "Rate not accurate. requested (%u), actual (%u)\n", 687 sample_freq, spi_freq / oversamp); 688 689 ret = stm32_dfsdm_compute_all_osrs(indio_dev, oversamp); 690 if (ret < 0) 691 return ret; 692 693 adc->sample_freq = spi_freq / oversamp; 694 adc->oversamp = oversamp; 695 696 return 0; 697 } 698 699 static ssize_t dfsdm_adc_audio_set_spiclk(struct iio_dev *indio_dev, 700 uintptr_t priv, 701 const struct iio_chan_spec *chan, 702 const char *buf, size_t len) 703 { 704 struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); 705 struct stm32_dfsdm_channel *ch = &adc->dfsdm->ch_list[chan->channel]; 706 unsigned int sample_freq = adc->sample_freq; 707 unsigned int spi_freq; 708 int ret; 709 710 dev_err(&indio_dev->dev, "enter %s\n", __func__); 711 /* If DFSDM is master on SPI, SPI freq can not be updated */ 712 if (ch->src != DFSDM_CHANNEL_SPI_CLOCK_EXTERNAL) 713 return -EPERM; 714 715 ret = kstrtoint(buf, 0, &spi_freq); 716 if (ret) 717 return ret; 718 719 if (!spi_freq) 720 return -EINVAL; 721 722 if (sample_freq) { 723 ret = dfsdm_adc_set_samp_freq(indio_dev, sample_freq, spi_freq); 724 if (ret < 0) 725 return ret; 726 } 727 adc->spi_freq = spi_freq; 728 729 return len; 730 } 731 732 static int stm32_dfsdm_start_conv(struct iio_dev *indio_dev, 733 struct iio_trigger *trig) 734 { 735 struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); 736 struct regmap *regmap = adc->dfsdm->regmap; 737 int ret; 738 739 ret = stm32_dfsdm_channels_configure(indio_dev, adc->fl_id, trig); 740 if (ret < 0) 741 return ret; 742 743 ret = stm32_dfsdm_start_channel(indio_dev); 744 if (ret < 0) 745 return ret; 746 747 ret = stm32_dfsdm_filter_configure(indio_dev, adc->fl_id, trig); 748 if (ret < 0) 749 goto stop_channels; 750 751 ret = stm32_dfsdm_start_filter(adc, adc->fl_id, trig); 752 if (ret < 0) 753 goto filter_unconfigure; 754 755 return 0; 756 757 filter_unconfigure: 758 regmap_update_bits(regmap, DFSDM_CR1(adc->fl_id), 759 DFSDM_CR1_CFG_MASK, 0); 760 stop_channels: 761 stm32_dfsdm_stop_channel(indio_dev); 762 763 return ret; 764 } 765 766 static void stm32_dfsdm_stop_conv(struct iio_dev *indio_dev) 767 { 768 struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); 769 struct regmap *regmap = adc->dfsdm->regmap; 770 771 stm32_dfsdm_stop_filter(adc->dfsdm, adc->fl_id); 772 773 regmap_update_bits(regmap, DFSDM_CR1(adc->fl_id), 774 DFSDM_CR1_CFG_MASK, 0); 775 776 stm32_dfsdm_stop_channel(indio_dev); 777 } 778 779 static int stm32_dfsdm_set_watermark(struct iio_dev *indio_dev, 780 unsigned int val) 781 { 782 struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); 783 unsigned int watermark = DFSDM_DMA_BUFFER_SIZE / 2; 784 unsigned int rx_buf_sz = DFSDM_DMA_BUFFER_SIZE; 785 786 /* 787 * DMA cyclic transfers are used, buffer is split into two periods. 788 * There should be : 789 * - always one buffer (period) DMA is working on 790 * - one buffer (period) driver pushed to ASoC side. 791 */ 792 watermark = min(watermark, val * (unsigned int)(sizeof(u32))); 793 adc->buf_sz = min(rx_buf_sz, watermark * 2 * adc->nconv); 794 795 return 0; 796 } 797 798 static unsigned int stm32_dfsdm_adc_dma_residue(struct stm32_dfsdm_adc *adc) 799 { 800 struct dma_tx_state state; 801 enum dma_status status; 802 803 status = dmaengine_tx_status(adc->dma_chan, 804 adc->dma_chan->cookie, 805 &state); 806 if (status == DMA_IN_PROGRESS) { 807 /* Residue is size in bytes from end of buffer */ 808 unsigned int i = adc->buf_sz - state.residue; 809 unsigned int size; 810 811 /* Return available bytes */ 812 if (i >= adc->bufi) 813 size = i - adc->bufi; 814 else 815 size = adc->buf_sz + i - adc->bufi; 816 817 return size; 818 } 819 820 return 0; 821 } 822 823 static inline void stm32_dfsdm_process_data(struct stm32_dfsdm_adc *adc, 824 s32 *buffer) 825 { 826 struct stm32_dfsdm_filter *fl = &adc->dfsdm->fl_list[adc->fl_id]; 827 struct stm32_dfsdm_filter_osr *flo = &fl->flo[fl->fast]; 828 unsigned int i = adc->nconv; 829 s32 *ptr = buffer; 830 831 while (i--) { 832 /* Mask 8 LSB that contains the channel ID */ 833 *ptr &= 0xFFFFFF00; 834 /* Convert 2^(n-1) sample to 2^(n-1)-1 to avoid wrap-around */ 835 if (*ptr > flo->max) 836 *ptr -= 1; 837 /* 838 * Samples from filter are retrieved with 23 bits resolution 839 * or less. Shift left to align MSB on 24 bits. 840 */ 841 *ptr <<= flo->lshift; 842 843 ptr++; 844 } 845 } 846 847 static void stm32_dfsdm_dma_buffer_done(void *data) 848 { 849 struct iio_dev *indio_dev = data; 850 struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); 851 int available = stm32_dfsdm_adc_dma_residue(adc); 852 size_t old_pos; 853 854 /* 855 * FIXME: In Kernel interface does not support cyclic DMA buffer,and 856 * offers only an interface to push data samples per samples. 857 * For this reason IIO buffer interface is not used and interface is 858 * bypassed using a private callback registered by ASoC. 859 * This should be a temporary solution waiting a cyclic DMA engine 860 * support in IIO. 861 */ 862 863 dev_dbg(&indio_dev->dev, "%s: pos = %d, available = %d\n", __func__, 864 adc->bufi, available); 865 old_pos = adc->bufi; 866 867 while (available >= indio_dev->scan_bytes) { 868 s32 *buffer = (s32 *)&adc->rx_buf[adc->bufi]; 869 870 stm32_dfsdm_process_data(adc, buffer); 871 872 available -= indio_dev->scan_bytes; 873 adc->bufi += indio_dev->scan_bytes; 874 if (adc->bufi >= adc->buf_sz) { 875 if (adc->cb) 876 adc->cb(&adc->rx_buf[old_pos], 877 adc->buf_sz - old_pos, adc->cb_priv); 878 adc->bufi = 0; 879 old_pos = 0; 880 } 881 /* 882 * In DMA mode the trigger services of IIO are not used 883 * (e.g. no call to iio_trigger_poll). 884 * Calling irq handler associated to the hardware trigger is not 885 * relevant as the conversions have already been done. Data 886 * transfers are performed directly in DMA callback instead. 887 * This implementation avoids to call trigger irq handler that 888 * may sleep, in an atomic context (DMA irq handler context). 889 */ 890 if (adc->dev_data->type == DFSDM_IIO) 891 iio_push_to_buffers(indio_dev, buffer); 892 } 893 if (adc->cb) 894 adc->cb(&adc->rx_buf[old_pos], adc->bufi - old_pos, 895 adc->cb_priv); 896 } 897 898 static int stm32_dfsdm_adc_dma_start(struct iio_dev *indio_dev) 899 { 900 struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); 901 /* 902 * The DFSDM supports half-word transfers. However, for 16 bits record, 903 * 4 bytes buswidth is kept, to avoid losing samples LSBs when left 904 * shift is required. 905 */ 906 struct dma_slave_config config = { 907 .src_addr = (dma_addr_t)adc->dfsdm->phys_base, 908 .src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES, 909 }; 910 struct dma_async_tx_descriptor *desc; 911 dma_cookie_t cookie; 912 int ret; 913 914 if (!adc->dma_chan) 915 return -EINVAL; 916 917 dev_dbg(&indio_dev->dev, "%s size=%d watermark=%d\n", __func__, 918 adc->buf_sz, adc->buf_sz / 2); 919 920 if (adc->nconv == 1 && !indio_dev->trig) 921 config.src_addr += DFSDM_RDATAR(adc->fl_id); 922 else 923 config.src_addr += DFSDM_JDATAR(adc->fl_id); 924 ret = dmaengine_slave_config(adc->dma_chan, &config); 925 if (ret) 926 return ret; 927 928 /* Prepare a DMA cyclic transaction */ 929 desc = dmaengine_prep_dma_cyclic(adc->dma_chan, 930 adc->dma_buf, 931 adc->buf_sz, adc->buf_sz / 2, 932 DMA_DEV_TO_MEM, 933 DMA_PREP_INTERRUPT); 934 if (!desc) 935 return -EBUSY; 936 937 desc->callback = stm32_dfsdm_dma_buffer_done; 938 desc->callback_param = indio_dev; 939 940 cookie = dmaengine_submit(desc); 941 ret = dma_submit_error(cookie); 942 if (ret) 943 goto err_stop_dma; 944 945 /* Issue pending DMA requests */ 946 dma_async_issue_pending(adc->dma_chan); 947 948 if (adc->nconv == 1 && !indio_dev->trig) { 949 /* Enable regular DMA transfer*/ 950 ret = regmap_update_bits(adc->dfsdm->regmap, 951 DFSDM_CR1(adc->fl_id), 952 DFSDM_CR1_RDMAEN_MASK, 953 DFSDM_CR1_RDMAEN_MASK); 954 } else { 955 /* Enable injected DMA transfer*/ 956 ret = regmap_update_bits(adc->dfsdm->regmap, 957 DFSDM_CR1(adc->fl_id), 958 DFSDM_CR1_JDMAEN_MASK, 959 DFSDM_CR1_JDMAEN_MASK); 960 } 961 962 if (ret < 0) 963 goto err_stop_dma; 964 965 return 0; 966 967 err_stop_dma: 968 dmaengine_terminate_all(adc->dma_chan); 969 970 return ret; 971 } 972 973 static void stm32_dfsdm_adc_dma_stop(struct iio_dev *indio_dev) 974 { 975 struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); 976 977 if (!adc->dma_chan) 978 return; 979 980 regmap_update_bits(adc->dfsdm->regmap, DFSDM_CR1(adc->fl_id), 981 DFSDM_CR1_RDMAEN_MASK | DFSDM_CR1_JDMAEN_MASK, 0); 982 dmaengine_terminate_all(adc->dma_chan); 983 } 984 985 static int stm32_dfsdm_update_scan_mode(struct iio_dev *indio_dev, 986 const unsigned long *scan_mask) 987 { 988 struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); 989 990 adc->nconv = bitmap_weight(scan_mask, indio_dev->masklength); 991 adc->smask = *scan_mask; 992 993 dev_dbg(&indio_dev->dev, "nconv=%d mask=%lx\n", adc->nconv, *scan_mask); 994 995 return 0; 996 } 997 998 static int stm32_dfsdm_postenable(struct iio_dev *indio_dev) 999 { 1000 struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); 1001 int ret; 1002 1003 /* Reset adc buffer index */ 1004 adc->bufi = 0; 1005 1006 if (adc->hwc) { 1007 ret = iio_hw_consumer_enable(adc->hwc); 1008 if (ret < 0) 1009 return ret; 1010 } 1011 1012 ret = stm32_dfsdm_start_dfsdm(adc->dfsdm); 1013 if (ret < 0) 1014 goto err_stop_hwc; 1015 1016 ret = stm32_dfsdm_adc_dma_start(indio_dev); 1017 if (ret) { 1018 dev_err(&indio_dev->dev, "Can't start DMA\n"); 1019 goto stop_dfsdm; 1020 } 1021 1022 ret = stm32_dfsdm_start_conv(indio_dev, indio_dev->trig); 1023 if (ret) { 1024 dev_err(&indio_dev->dev, "Can't start conversion\n"); 1025 goto err_stop_dma; 1026 } 1027 1028 return 0; 1029 1030 err_stop_dma: 1031 stm32_dfsdm_adc_dma_stop(indio_dev); 1032 stop_dfsdm: 1033 stm32_dfsdm_stop_dfsdm(adc->dfsdm); 1034 err_stop_hwc: 1035 if (adc->hwc) 1036 iio_hw_consumer_disable(adc->hwc); 1037 1038 return ret; 1039 } 1040 1041 static int stm32_dfsdm_predisable(struct iio_dev *indio_dev) 1042 { 1043 struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); 1044 1045 stm32_dfsdm_stop_conv(indio_dev); 1046 1047 stm32_dfsdm_adc_dma_stop(indio_dev); 1048 1049 stm32_dfsdm_stop_dfsdm(adc->dfsdm); 1050 1051 if (adc->hwc) 1052 iio_hw_consumer_disable(adc->hwc); 1053 1054 return 0; 1055 } 1056 1057 static const struct iio_buffer_setup_ops stm32_dfsdm_buffer_setup_ops = { 1058 .postenable = &stm32_dfsdm_postenable, 1059 .predisable = &stm32_dfsdm_predisable, 1060 }; 1061 1062 /** 1063 * stm32_dfsdm_get_buff_cb() - register a callback that will be called when 1064 * DMA transfer period is achieved. 1065 * 1066 * @iio_dev: Handle to IIO device. 1067 * @cb: Pointer to callback function: 1068 * - data: pointer to data buffer 1069 * - size: size in byte of the data buffer 1070 * - private: pointer to consumer private structure. 1071 * @private: Pointer to consumer private structure. 1072 */ 1073 int stm32_dfsdm_get_buff_cb(struct iio_dev *iio_dev, 1074 int (*cb)(const void *data, size_t size, 1075 void *private), 1076 void *private) 1077 { 1078 struct stm32_dfsdm_adc *adc; 1079 1080 if (!iio_dev) 1081 return -EINVAL; 1082 adc = iio_priv(iio_dev); 1083 1084 adc->cb = cb; 1085 adc->cb_priv = private; 1086 1087 return 0; 1088 } 1089 EXPORT_SYMBOL_GPL(stm32_dfsdm_get_buff_cb); 1090 1091 /** 1092 * stm32_dfsdm_release_buff_cb - unregister buffer callback 1093 * 1094 * @iio_dev: Handle to IIO device. 1095 */ 1096 int stm32_dfsdm_release_buff_cb(struct iio_dev *iio_dev) 1097 { 1098 struct stm32_dfsdm_adc *adc; 1099 1100 if (!iio_dev) 1101 return -EINVAL; 1102 adc = iio_priv(iio_dev); 1103 1104 adc->cb = NULL; 1105 adc->cb_priv = NULL; 1106 1107 return 0; 1108 } 1109 EXPORT_SYMBOL_GPL(stm32_dfsdm_release_buff_cb); 1110 1111 static int stm32_dfsdm_single_conv(struct iio_dev *indio_dev, 1112 const struct iio_chan_spec *chan, int *res) 1113 { 1114 struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); 1115 long timeout; 1116 int ret; 1117 1118 reinit_completion(&adc->completion); 1119 1120 adc->buffer = res; 1121 1122 ret = stm32_dfsdm_start_dfsdm(adc->dfsdm); 1123 if (ret < 0) 1124 return ret; 1125 1126 ret = regmap_update_bits(adc->dfsdm->regmap, DFSDM_CR2(adc->fl_id), 1127 DFSDM_CR2_REOCIE_MASK, DFSDM_CR2_REOCIE(1)); 1128 if (ret < 0) 1129 goto stop_dfsdm; 1130 1131 adc->nconv = 1; 1132 adc->smask = BIT(chan->scan_index); 1133 ret = stm32_dfsdm_start_conv(indio_dev, NULL); 1134 if (ret < 0) { 1135 regmap_update_bits(adc->dfsdm->regmap, DFSDM_CR2(adc->fl_id), 1136 DFSDM_CR2_REOCIE_MASK, DFSDM_CR2_REOCIE(0)); 1137 goto stop_dfsdm; 1138 } 1139 1140 timeout = wait_for_completion_interruptible_timeout(&adc->completion, 1141 DFSDM_TIMEOUT); 1142 1143 /* Mask IRQ for regular conversion achievement*/ 1144 regmap_update_bits(adc->dfsdm->regmap, DFSDM_CR2(adc->fl_id), 1145 DFSDM_CR2_REOCIE_MASK, DFSDM_CR2_REOCIE(0)); 1146 1147 if (timeout == 0) 1148 ret = -ETIMEDOUT; 1149 else if (timeout < 0) 1150 ret = timeout; 1151 else 1152 ret = IIO_VAL_INT; 1153 1154 stm32_dfsdm_stop_conv(indio_dev); 1155 1156 stm32_dfsdm_process_data(adc, res); 1157 1158 stop_dfsdm: 1159 stm32_dfsdm_stop_dfsdm(adc->dfsdm); 1160 1161 return ret; 1162 } 1163 1164 static int stm32_dfsdm_write_raw(struct iio_dev *indio_dev, 1165 struct iio_chan_spec const *chan, 1166 int val, int val2, long mask) 1167 { 1168 struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); 1169 struct stm32_dfsdm_channel *ch = &adc->dfsdm->ch_list[chan->channel]; 1170 unsigned int spi_freq; 1171 int ret = -EINVAL; 1172 1173 switch (ch->src) { 1174 case DFSDM_CHANNEL_SPI_CLOCK_INTERNAL: 1175 spi_freq = adc->dfsdm->spi_master_freq; 1176 break; 1177 case DFSDM_CHANNEL_SPI_CLOCK_INTERNAL_DIV2_FALLING: 1178 case DFSDM_CHANNEL_SPI_CLOCK_INTERNAL_DIV2_RISING: 1179 spi_freq = adc->dfsdm->spi_master_freq / 2; 1180 break; 1181 default: 1182 spi_freq = adc->spi_freq; 1183 } 1184 1185 switch (mask) { 1186 case IIO_CHAN_INFO_OVERSAMPLING_RATIO: 1187 ret = iio_device_claim_direct_mode(indio_dev); 1188 if (ret) 1189 return ret; 1190 1191 ret = stm32_dfsdm_compute_all_osrs(indio_dev, val); 1192 if (!ret) { 1193 dev_dbg(&indio_dev->dev, 1194 "Sampling rate changed from (%u) to (%u)\n", 1195 adc->sample_freq, spi_freq / val); 1196 adc->oversamp = val; 1197 adc->sample_freq = spi_freq / val; 1198 } 1199 iio_device_release_direct_mode(indio_dev); 1200 return ret; 1201 1202 case IIO_CHAN_INFO_SAMP_FREQ: 1203 if (!val) 1204 return -EINVAL; 1205 1206 ret = iio_device_claim_direct_mode(indio_dev); 1207 if (ret) 1208 return ret; 1209 1210 ret = dfsdm_adc_set_samp_freq(indio_dev, val, spi_freq); 1211 iio_device_release_direct_mode(indio_dev); 1212 return ret; 1213 } 1214 1215 return -EINVAL; 1216 } 1217 1218 static int stm32_dfsdm_read_raw(struct iio_dev *indio_dev, 1219 struct iio_chan_spec const *chan, int *val, 1220 int *val2, long mask) 1221 { 1222 struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); 1223 int ret; 1224 1225 switch (mask) { 1226 case IIO_CHAN_INFO_RAW: 1227 ret = iio_device_claim_direct_mode(indio_dev); 1228 if (ret) 1229 return ret; 1230 ret = iio_hw_consumer_enable(adc->hwc); 1231 if (ret < 0) { 1232 dev_err(&indio_dev->dev, 1233 "%s: IIO enable failed (channel %d)\n", 1234 __func__, chan->channel); 1235 iio_device_release_direct_mode(indio_dev); 1236 return ret; 1237 } 1238 ret = stm32_dfsdm_single_conv(indio_dev, chan, val); 1239 iio_hw_consumer_disable(adc->hwc); 1240 if (ret < 0) { 1241 dev_err(&indio_dev->dev, 1242 "%s: Conversion failed (channel %d)\n", 1243 __func__, chan->channel); 1244 iio_device_release_direct_mode(indio_dev); 1245 return ret; 1246 } 1247 iio_device_release_direct_mode(indio_dev); 1248 return IIO_VAL_INT; 1249 1250 case IIO_CHAN_INFO_OVERSAMPLING_RATIO: 1251 *val = adc->oversamp; 1252 1253 return IIO_VAL_INT; 1254 1255 case IIO_CHAN_INFO_SAMP_FREQ: 1256 *val = adc->sample_freq; 1257 1258 return IIO_VAL_INT; 1259 } 1260 1261 return -EINVAL; 1262 } 1263 1264 static int stm32_dfsdm_validate_trigger(struct iio_dev *indio_dev, 1265 struct iio_trigger *trig) 1266 { 1267 return stm32_dfsdm_get_jextsel(indio_dev, trig) < 0 ? -EINVAL : 0; 1268 } 1269 1270 static const struct iio_info stm32_dfsdm_info_audio = { 1271 .hwfifo_set_watermark = stm32_dfsdm_set_watermark, 1272 .read_raw = stm32_dfsdm_read_raw, 1273 .write_raw = stm32_dfsdm_write_raw, 1274 .update_scan_mode = stm32_dfsdm_update_scan_mode, 1275 }; 1276 1277 static const struct iio_info stm32_dfsdm_info_adc = { 1278 .hwfifo_set_watermark = stm32_dfsdm_set_watermark, 1279 .read_raw = stm32_dfsdm_read_raw, 1280 .write_raw = stm32_dfsdm_write_raw, 1281 .update_scan_mode = stm32_dfsdm_update_scan_mode, 1282 .validate_trigger = stm32_dfsdm_validate_trigger, 1283 }; 1284 1285 static irqreturn_t stm32_dfsdm_irq(int irq, void *arg) 1286 { 1287 struct iio_dev *indio_dev = arg; 1288 struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); 1289 struct regmap *regmap = adc->dfsdm->regmap; 1290 unsigned int status, int_en; 1291 1292 regmap_read(regmap, DFSDM_ISR(adc->fl_id), &status); 1293 regmap_read(regmap, DFSDM_CR2(adc->fl_id), &int_en); 1294 1295 if (status & DFSDM_ISR_REOCF_MASK) { 1296 /* Read the data register clean the IRQ status */ 1297 regmap_read(regmap, DFSDM_RDATAR(adc->fl_id), adc->buffer); 1298 complete(&adc->completion); 1299 } 1300 1301 if (status & DFSDM_ISR_ROVRF_MASK) { 1302 if (int_en & DFSDM_CR2_ROVRIE_MASK) 1303 dev_warn(&indio_dev->dev, "Overrun detected\n"); 1304 regmap_update_bits(regmap, DFSDM_ICR(adc->fl_id), 1305 DFSDM_ICR_CLRROVRF_MASK, 1306 DFSDM_ICR_CLRROVRF_MASK); 1307 } 1308 1309 return IRQ_HANDLED; 1310 } 1311 1312 /* 1313 * Define external info for SPI Frequency and audio sampling rate that can be 1314 * configured by ASoC driver through consumer.h API 1315 */ 1316 static const struct iio_chan_spec_ext_info dfsdm_adc_audio_ext_info[] = { 1317 /* spi_clk_freq : clock freq on SPI/manchester bus used by channel */ 1318 { 1319 .name = "spi_clk_freq", 1320 .shared = IIO_SHARED_BY_TYPE, 1321 .read = dfsdm_adc_audio_get_spiclk, 1322 .write = dfsdm_adc_audio_set_spiclk, 1323 }, 1324 {}, 1325 }; 1326 1327 static void stm32_dfsdm_dma_release(struct iio_dev *indio_dev) 1328 { 1329 struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); 1330 1331 if (adc->dma_chan) { 1332 dma_free_coherent(adc->dma_chan->device->dev, 1333 DFSDM_DMA_BUFFER_SIZE, 1334 adc->rx_buf, adc->dma_buf); 1335 dma_release_channel(adc->dma_chan); 1336 } 1337 } 1338 1339 static int stm32_dfsdm_dma_request(struct device *dev, 1340 struct iio_dev *indio_dev) 1341 { 1342 struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); 1343 1344 adc->dma_chan = dma_request_chan(dev, "rx"); 1345 if (IS_ERR(adc->dma_chan)) { 1346 int ret = PTR_ERR(adc->dma_chan); 1347 1348 adc->dma_chan = NULL; 1349 return ret; 1350 } 1351 1352 adc->rx_buf = dma_alloc_coherent(adc->dma_chan->device->dev, 1353 DFSDM_DMA_BUFFER_SIZE, 1354 &adc->dma_buf, GFP_KERNEL); 1355 if (!adc->rx_buf) { 1356 dma_release_channel(adc->dma_chan); 1357 return -ENOMEM; 1358 } 1359 1360 indio_dev->modes |= INDIO_BUFFER_SOFTWARE; 1361 indio_dev->setup_ops = &stm32_dfsdm_buffer_setup_ops; 1362 1363 return 0; 1364 } 1365 1366 static int stm32_dfsdm_adc_chan_init_one(struct iio_dev *indio_dev, 1367 struct iio_chan_spec *ch) 1368 { 1369 struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); 1370 int ret; 1371 1372 ret = stm32_dfsdm_channel_parse_of(adc->dfsdm, indio_dev, ch); 1373 if (ret < 0) 1374 return ret; 1375 1376 ch->type = IIO_VOLTAGE; 1377 ch->indexed = 1; 1378 1379 /* 1380 * IIO_CHAN_INFO_RAW: used to compute regular conversion 1381 * IIO_CHAN_INFO_OVERSAMPLING_RATIO: used to set oversampling 1382 */ 1383 ch->info_mask_separate = BIT(IIO_CHAN_INFO_RAW); 1384 ch->info_mask_shared_by_all = BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO) | 1385 BIT(IIO_CHAN_INFO_SAMP_FREQ); 1386 1387 if (adc->dev_data->type == DFSDM_AUDIO) { 1388 ch->ext_info = dfsdm_adc_audio_ext_info; 1389 } else { 1390 ch->scan_type.shift = 8; 1391 } 1392 ch->scan_type.sign = 's'; 1393 ch->scan_type.realbits = 24; 1394 ch->scan_type.storagebits = 32; 1395 1396 return stm32_dfsdm_chan_configure(adc->dfsdm, 1397 &adc->dfsdm->ch_list[ch->channel]); 1398 } 1399 1400 static int stm32_dfsdm_audio_init(struct device *dev, struct iio_dev *indio_dev) 1401 { 1402 struct iio_chan_spec *ch; 1403 struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); 1404 struct stm32_dfsdm_channel *d_ch; 1405 int ret; 1406 1407 ch = devm_kzalloc(&indio_dev->dev, sizeof(*ch), GFP_KERNEL); 1408 if (!ch) 1409 return -ENOMEM; 1410 1411 ch->scan_index = 0; 1412 1413 ret = stm32_dfsdm_adc_chan_init_one(indio_dev, ch); 1414 if (ret < 0) { 1415 dev_err(&indio_dev->dev, "Channels init failed\n"); 1416 return ret; 1417 } 1418 ch->info_mask_separate = BIT(IIO_CHAN_INFO_SAMP_FREQ); 1419 1420 d_ch = &adc->dfsdm->ch_list[ch->channel]; 1421 if (d_ch->src != DFSDM_CHANNEL_SPI_CLOCK_EXTERNAL) 1422 adc->spi_freq = adc->dfsdm->spi_master_freq; 1423 1424 indio_dev->num_channels = 1; 1425 indio_dev->channels = ch; 1426 1427 return stm32_dfsdm_dma_request(dev, indio_dev); 1428 } 1429 1430 static int stm32_dfsdm_adc_init(struct device *dev, struct iio_dev *indio_dev) 1431 { 1432 struct iio_chan_spec *ch; 1433 struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); 1434 int num_ch; 1435 int ret, chan_idx; 1436 1437 adc->oversamp = DFSDM_DEFAULT_OVERSAMPLING; 1438 ret = stm32_dfsdm_compute_all_osrs(indio_dev, adc->oversamp); 1439 if (ret < 0) 1440 return ret; 1441 1442 num_ch = of_property_count_u32_elems(indio_dev->dev.of_node, 1443 "st,adc-channels"); 1444 if (num_ch < 0 || num_ch > adc->dfsdm->num_chs) { 1445 dev_err(&indio_dev->dev, "Bad st,adc-channels\n"); 1446 return num_ch < 0 ? num_ch : -EINVAL; 1447 } 1448 1449 /* Bind to SD modulator IIO device */ 1450 adc->hwc = devm_iio_hw_consumer_alloc(&indio_dev->dev); 1451 if (IS_ERR(adc->hwc)) 1452 return -EPROBE_DEFER; 1453 1454 ch = devm_kcalloc(&indio_dev->dev, num_ch, sizeof(*ch), 1455 GFP_KERNEL); 1456 if (!ch) 1457 return -ENOMEM; 1458 1459 for (chan_idx = 0; chan_idx < num_ch; chan_idx++) { 1460 ch[chan_idx].scan_index = chan_idx; 1461 ret = stm32_dfsdm_adc_chan_init_one(indio_dev, &ch[chan_idx]); 1462 if (ret < 0) { 1463 dev_err(&indio_dev->dev, "Channels init failed\n"); 1464 return ret; 1465 } 1466 } 1467 1468 indio_dev->num_channels = num_ch; 1469 indio_dev->channels = ch; 1470 1471 init_completion(&adc->completion); 1472 1473 /* Optionally request DMA */ 1474 ret = stm32_dfsdm_dma_request(dev, indio_dev); 1475 if (ret) { 1476 if (ret != -ENODEV) { 1477 if (ret != -EPROBE_DEFER) 1478 dev_err(dev, 1479 "DMA channel request failed with %d\n", 1480 ret); 1481 return ret; 1482 } 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