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("Requested oversampling: %d\n", 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("fast %d, fosr %d, iosr %d, res 0x%llx/%d bits, rshift %d, lshift %d\n", 299 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 && iio_buffer_enabled(indio_dev)) { 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 dev_dbg(&indio_dev->dev, "Samples actual resolution: %d bits", 480 min(flo->bits, (u32)DFSDM_DATA_RES - 1)); 481 482 for_each_set_bit(bit, &adc->smask, 483 sizeof(adc->smask) * BITS_PER_BYTE) { 484 chan = indio_dev->channels + bit; 485 486 ret = regmap_update_bits(regmap, 487 DFSDM_CHCFGR2(chan->channel), 488 DFSDM_CHCFGR2_DTRBS_MASK, 489 DFSDM_CHCFGR2_DTRBS(flo->rshift)); 490 if (ret) 491 return ret; 492 } 493 494 return 0; 495 } 496 497 static int stm32_dfsdm_filter_configure(struct iio_dev *indio_dev, 498 unsigned int fl_id, 499 struct iio_trigger *trig) 500 { 501 struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); 502 struct regmap *regmap = adc->dfsdm->regmap; 503 struct stm32_dfsdm_filter *fl = &adc->dfsdm->fl_list[fl_id]; 504 struct stm32_dfsdm_filter_osr *flo = &fl->flo[fl->fast]; 505 u32 cr1; 506 const struct iio_chan_spec *chan; 507 unsigned int bit, jchg = 0; 508 int ret; 509 510 /* Average integrator oversampling */ 511 ret = regmap_update_bits(regmap, DFSDM_FCR(fl_id), DFSDM_FCR_IOSR_MASK, 512 DFSDM_FCR_IOSR(flo->iosr - 1)); 513 if (ret) 514 return ret; 515 516 /* Filter order and Oversampling */ 517 ret = regmap_update_bits(regmap, DFSDM_FCR(fl_id), DFSDM_FCR_FOSR_MASK, 518 DFSDM_FCR_FOSR(flo->fosr - 1)); 519 if (ret) 520 return ret; 521 522 ret = regmap_update_bits(regmap, DFSDM_FCR(fl_id), DFSDM_FCR_FORD_MASK, 523 DFSDM_FCR_FORD(fl->ford)); 524 if (ret) 525 return ret; 526 527 ret = stm32_dfsdm_filter_set_trig(indio_dev, fl_id, trig); 528 if (ret) 529 return ret; 530 531 ret = regmap_update_bits(regmap, DFSDM_CR1(fl_id), 532 DFSDM_CR1_FAST_MASK, 533 DFSDM_CR1_FAST(fl->fast)); 534 if (ret) 535 return ret; 536 537 /* 538 * DFSDM modes configuration W.R.T audio/iio type modes 539 * ---------------------------------------------------------------- 540 * Modes | regular | regular | injected | injected | 541 * | | continuous | | + scan | 542 * --------------|---------|--------------|----------|------------| 543 * single conv | x | | | | 544 * (1 chan) | | | | | 545 * --------------|---------|--------------|----------|------------| 546 * 1 Audio chan | | sample freq | | | 547 * | | or sync_mode | | | 548 * --------------|---------|--------------|----------|------------| 549 * 1 IIO chan | | sample freq | trigger | | 550 * | | or sync_mode | | | 551 * --------------|---------|--------------|----------|------------| 552 * 2+ IIO chans | | | | trigger or | 553 * | | | | sync_mode | 554 * ---------------------------------------------------------------- 555 */ 556 if (adc->nconv == 1 && !trig) { 557 bit = __ffs(adc->smask); 558 chan = indio_dev->channels + bit; 559 560 /* Use regular conversion for single channel without trigger */ 561 cr1 = DFSDM_CR1_RCH(chan->channel); 562 563 /* Continuous conversions triggered by SPI clk in buffer mode */ 564 if (iio_buffer_enabled(indio_dev)) 565 cr1 |= DFSDM_CR1_RCONT(1); 566 567 cr1 |= DFSDM_CR1_RSYNC(fl->sync_mode); 568 } else { 569 /* Use injected conversion for multiple channels */ 570 for_each_set_bit(bit, &adc->smask, 571 sizeof(adc->smask) * BITS_PER_BYTE) { 572 chan = indio_dev->channels + bit; 573 jchg |= BIT(chan->channel); 574 } 575 ret = regmap_write(regmap, DFSDM_JCHGR(fl_id), jchg); 576 if (ret < 0) 577 return ret; 578 579 /* Use scan mode for multiple channels */ 580 cr1 = DFSDM_CR1_JSCAN((adc->nconv > 1) ? 1 : 0); 581 582 /* 583 * Continuous conversions not supported in injected mode, 584 * either use: 585 * - conversions in sync with filter 0 586 * - triggered conversions 587 */ 588 if (!fl->sync_mode && !trig) 589 return -EINVAL; 590 cr1 |= DFSDM_CR1_JSYNC(fl->sync_mode); 591 } 592 593 return regmap_update_bits(regmap, DFSDM_CR1(fl_id), DFSDM_CR1_CFG_MASK, 594 cr1); 595 } 596 597 static int stm32_dfsdm_channel_parse_of(struct stm32_dfsdm *dfsdm, 598 struct iio_dev *indio_dev, 599 struct iio_chan_spec *ch) 600 { 601 struct stm32_dfsdm_channel *df_ch; 602 const char *of_str; 603 int chan_idx = ch->scan_index; 604 int ret, val; 605 606 ret = of_property_read_u32_index(indio_dev->dev.of_node, 607 "st,adc-channels", chan_idx, 608 &ch->channel); 609 if (ret < 0) { 610 dev_err(&indio_dev->dev, 611 " Error parsing 'st,adc-channels' for idx %d\n", 612 chan_idx); 613 return ret; 614 } 615 if (ch->channel >= dfsdm->num_chs) { 616 dev_err(&indio_dev->dev, 617 " Error bad channel number %d (max = %d)\n", 618 ch->channel, dfsdm->num_chs); 619 return -EINVAL; 620 } 621 622 ret = of_property_read_string_index(indio_dev->dev.of_node, 623 "st,adc-channel-names", chan_idx, 624 &ch->datasheet_name); 625 if (ret < 0) { 626 dev_err(&indio_dev->dev, 627 " Error parsing 'st,adc-channel-names' for idx %d\n", 628 chan_idx); 629 return ret; 630 } 631 632 df_ch = &dfsdm->ch_list[ch->channel]; 633 df_ch->id = ch->channel; 634 635 ret = of_property_read_string_index(indio_dev->dev.of_node, 636 "st,adc-channel-types", chan_idx, 637 &of_str); 638 if (!ret) { 639 val = stm32_dfsdm_str2val(of_str, stm32_dfsdm_chan_type); 640 if (val < 0) 641 return val; 642 } else { 643 val = 0; 644 } 645 df_ch->type = val; 646 647 ret = of_property_read_string_index(indio_dev->dev.of_node, 648 "st,adc-channel-clk-src", chan_idx, 649 &of_str); 650 if (!ret) { 651 val = stm32_dfsdm_str2val(of_str, stm32_dfsdm_chan_src); 652 if (val < 0) 653 return val; 654 } else { 655 val = 0; 656 } 657 df_ch->src = val; 658 659 ret = of_property_read_u32_index(indio_dev->dev.of_node, 660 "st,adc-alt-channel", chan_idx, 661 &df_ch->alt_si); 662 if (ret < 0) 663 df_ch->alt_si = 0; 664 665 return 0; 666 } 667 668 static ssize_t dfsdm_adc_audio_get_spiclk(struct iio_dev *indio_dev, 669 uintptr_t priv, 670 const struct iio_chan_spec *chan, 671 char *buf) 672 { 673 struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); 674 675 return snprintf(buf, PAGE_SIZE, "%d\n", adc->spi_freq); 676 } 677 678 static int dfsdm_adc_set_samp_freq(struct iio_dev *indio_dev, 679 unsigned int sample_freq, 680 unsigned int spi_freq) 681 { 682 struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); 683 unsigned int oversamp; 684 int ret; 685 686 oversamp = DIV_ROUND_CLOSEST(spi_freq, sample_freq); 687 if (spi_freq % sample_freq) 688 dev_dbg(&indio_dev->dev, 689 "Rate not accurate. requested (%u), actual (%u)\n", 690 sample_freq, spi_freq / oversamp); 691 692 ret = stm32_dfsdm_compute_all_osrs(indio_dev, oversamp); 693 if (ret < 0) 694 return ret; 695 696 adc->sample_freq = spi_freq / oversamp; 697 adc->oversamp = oversamp; 698 699 return 0; 700 } 701 702 static ssize_t dfsdm_adc_audio_set_spiclk(struct iio_dev *indio_dev, 703 uintptr_t priv, 704 const struct iio_chan_spec *chan, 705 const char *buf, size_t len) 706 { 707 struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); 708 struct stm32_dfsdm_channel *ch = &adc->dfsdm->ch_list[chan->channel]; 709 unsigned int sample_freq = adc->sample_freq; 710 unsigned int spi_freq; 711 int ret; 712 713 dev_err(&indio_dev->dev, "enter %s\n", __func__); 714 /* If DFSDM is master on SPI, SPI freq can not be updated */ 715 if (ch->src != DFSDM_CHANNEL_SPI_CLOCK_EXTERNAL) 716 return -EPERM; 717 718 ret = kstrtoint(buf, 0, &spi_freq); 719 if (ret) 720 return ret; 721 722 if (!spi_freq) 723 return -EINVAL; 724 725 if (sample_freq) { 726 ret = dfsdm_adc_set_samp_freq(indio_dev, sample_freq, spi_freq); 727 if (ret < 0) 728 return ret; 729 } 730 adc->spi_freq = spi_freq; 731 732 return len; 733 } 734 735 static int stm32_dfsdm_start_conv(struct iio_dev *indio_dev, 736 struct iio_trigger *trig) 737 { 738 struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); 739 struct regmap *regmap = adc->dfsdm->regmap; 740 int ret; 741 742 ret = stm32_dfsdm_channels_configure(indio_dev, adc->fl_id, trig); 743 if (ret < 0) 744 return ret; 745 746 ret = stm32_dfsdm_start_channel(indio_dev); 747 if (ret < 0) 748 return ret; 749 750 ret = stm32_dfsdm_filter_configure(indio_dev, adc->fl_id, trig); 751 if (ret < 0) 752 goto stop_channels; 753 754 ret = stm32_dfsdm_start_filter(adc, adc->fl_id, trig); 755 if (ret < 0) 756 goto filter_unconfigure; 757 758 return 0; 759 760 filter_unconfigure: 761 regmap_update_bits(regmap, DFSDM_CR1(adc->fl_id), 762 DFSDM_CR1_CFG_MASK, 0); 763 stop_channels: 764 stm32_dfsdm_stop_channel(indio_dev); 765 766 return ret; 767 } 768 769 static void stm32_dfsdm_stop_conv(struct iio_dev *indio_dev) 770 { 771 struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); 772 struct regmap *regmap = adc->dfsdm->regmap; 773 774 stm32_dfsdm_stop_filter(adc->dfsdm, adc->fl_id); 775 776 regmap_update_bits(regmap, DFSDM_CR1(adc->fl_id), 777 DFSDM_CR1_CFG_MASK, 0); 778 779 stm32_dfsdm_stop_channel(indio_dev); 780 } 781 782 static int stm32_dfsdm_set_watermark(struct iio_dev *indio_dev, 783 unsigned int val) 784 { 785 struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); 786 unsigned int watermark = DFSDM_DMA_BUFFER_SIZE / 2; 787 unsigned int rx_buf_sz = DFSDM_DMA_BUFFER_SIZE; 788 789 /* 790 * DMA cyclic transfers are used, buffer is split into two periods. 791 * There should be : 792 * - always one buffer (period) DMA is working on 793 * - one buffer (period) driver pushed to ASoC side. 794 */ 795 watermark = min(watermark, val * (unsigned int)(sizeof(u32))); 796 adc->buf_sz = min(rx_buf_sz, watermark * 2 * adc->nconv); 797 798 return 0; 799 } 800 801 static unsigned int stm32_dfsdm_adc_dma_residue(struct stm32_dfsdm_adc *adc) 802 { 803 struct dma_tx_state state; 804 enum dma_status status; 805 806 status = dmaengine_tx_status(adc->dma_chan, 807 adc->dma_chan->cookie, 808 &state); 809 if (status == DMA_IN_PROGRESS) { 810 /* Residue is size in bytes from end of buffer */ 811 unsigned int i = adc->buf_sz - state.residue; 812 unsigned int size; 813 814 /* Return available bytes */ 815 if (i >= adc->bufi) 816 size = i - adc->bufi; 817 else 818 size = adc->buf_sz + i - adc->bufi; 819 820 return size; 821 } 822 823 return 0; 824 } 825 826 static inline void stm32_dfsdm_process_data(struct stm32_dfsdm_adc *adc, 827 s32 *buffer) 828 { 829 struct stm32_dfsdm_filter *fl = &adc->dfsdm->fl_list[adc->fl_id]; 830 struct stm32_dfsdm_filter_osr *flo = &fl->flo[fl->fast]; 831 unsigned int i = adc->nconv; 832 s32 *ptr = buffer; 833 834 while (i--) { 835 /* Mask 8 LSB that contains the channel ID */ 836 *ptr &= 0xFFFFFF00; 837 /* Convert 2^(n-1) sample to 2^(n-1)-1 to avoid wrap-around */ 838 if (*ptr > flo->max) 839 *ptr -= 1; 840 /* 841 * Samples from filter are retrieved with 23 bits resolution 842 * or less. Shift left to align MSB on 24 bits. 843 */ 844 *ptr <<= flo->lshift; 845 846 ptr++; 847 } 848 } 849 850 static void stm32_dfsdm_dma_buffer_done(void *data) 851 { 852 struct iio_dev *indio_dev = data; 853 struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); 854 int available = stm32_dfsdm_adc_dma_residue(adc); 855 size_t old_pos; 856 857 /* 858 * FIXME: In Kernel interface does not support cyclic DMA buffer,and 859 * offers only an interface to push data samples per samples. 860 * For this reason IIO buffer interface is not used and interface is 861 * bypassed using a private callback registered by ASoC. 862 * This should be a temporary solution waiting a cyclic DMA engine 863 * support in IIO. 864 */ 865 866 dev_dbg(&indio_dev->dev, "pos = %d, available = %d\n", 867 adc->bufi, available); 868 old_pos = adc->bufi; 869 870 while (available >= indio_dev->scan_bytes) { 871 s32 *buffer = (s32 *)&adc->rx_buf[adc->bufi]; 872 873 stm32_dfsdm_process_data(adc, buffer); 874 875 available -= indio_dev->scan_bytes; 876 adc->bufi += indio_dev->scan_bytes; 877 if (adc->bufi >= adc->buf_sz) { 878 if (adc->cb) 879 adc->cb(&adc->rx_buf[old_pos], 880 adc->buf_sz - old_pos, adc->cb_priv); 881 adc->bufi = 0; 882 old_pos = 0; 883 } 884 /* 885 * In DMA mode the trigger services of IIO are not used 886 * (e.g. no call to iio_trigger_poll). 887 * Calling irq handler associated to the hardware trigger is not 888 * relevant as the conversions have already been done. Data 889 * transfers are performed directly in DMA callback instead. 890 * This implementation avoids to call trigger irq handler that 891 * may sleep, in an atomic context (DMA irq handler context). 892 */ 893 if (adc->dev_data->type == DFSDM_IIO) 894 iio_push_to_buffers(indio_dev, buffer); 895 } 896 if (adc->cb) 897 adc->cb(&adc->rx_buf[old_pos], adc->bufi - old_pos, 898 adc->cb_priv); 899 } 900 901 static int stm32_dfsdm_adc_dma_start(struct iio_dev *indio_dev) 902 { 903 struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); 904 /* 905 * The DFSDM supports half-word transfers. However, for 16 bits record, 906 * 4 bytes buswidth is kept, to avoid losing samples LSBs when left 907 * shift is required. 908 */ 909 struct dma_slave_config config = { 910 .src_addr = (dma_addr_t)adc->dfsdm->phys_base, 911 .src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES, 912 }; 913 struct dma_async_tx_descriptor *desc; 914 dma_cookie_t cookie; 915 int ret; 916 917 if (!adc->dma_chan) 918 return -EINVAL; 919 920 dev_dbg(&indio_dev->dev, "size=%d watermark=%d\n", 921 adc->buf_sz, adc->buf_sz / 2); 922 923 if (adc->nconv == 1 && !indio_dev->trig) 924 config.src_addr += DFSDM_RDATAR(adc->fl_id); 925 else 926 config.src_addr += DFSDM_JDATAR(adc->fl_id); 927 ret = dmaengine_slave_config(adc->dma_chan, &config); 928 if (ret) 929 return ret; 930 931 /* Prepare a DMA cyclic transaction */ 932 desc = dmaengine_prep_dma_cyclic(adc->dma_chan, 933 adc->dma_buf, 934 adc->buf_sz, adc->buf_sz / 2, 935 DMA_DEV_TO_MEM, 936 DMA_PREP_INTERRUPT); 937 if (!desc) 938 return -EBUSY; 939 940 desc->callback = stm32_dfsdm_dma_buffer_done; 941 desc->callback_param = indio_dev; 942 943 cookie = dmaengine_submit(desc); 944 ret = dma_submit_error(cookie); 945 if (ret) 946 goto err_stop_dma; 947 948 /* Issue pending DMA requests */ 949 dma_async_issue_pending(adc->dma_chan); 950 951 if (adc->nconv == 1 && !indio_dev->trig) { 952 /* Enable regular DMA transfer*/ 953 ret = regmap_update_bits(adc->dfsdm->regmap, 954 DFSDM_CR1(adc->fl_id), 955 DFSDM_CR1_RDMAEN_MASK, 956 DFSDM_CR1_RDMAEN_MASK); 957 } else { 958 /* Enable injected DMA transfer*/ 959 ret = regmap_update_bits(adc->dfsdm->regmap, 960 DFSDM_CR1(adc->fl_id), 961 DFSDM_CR1_JDMAEN_MASK, 962 DFSDM_CR1_JDMAEN_MASK); 963 } 964 965 if (ret < 0) 966 goto err_stop_dma; 967 968 return 0; 969 970 err_stop_dma: 971 dmaengine_terminate_all(adc->dma_chan); 972 973 return ret; 974 } 975 976 static void stm32_dfsdm_adc_dma_stop(struct iio_dev *indio_dev) 977 { 978 struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); 979 980 if (!adc->dma_chan) 981 return; 982 983 regmap_update_bits(adc->dfsdm->regmap, DFSDM_CR1(adc->fl_id), 984 DFSDM_CR1_RDMAEN_MASK | DFSDM_CR1_JDMAEN_MASK, 0); 985 dmaengine_terminate_all(adc->dma_chan); 986 } 987 988 static int stm32_dfsdm_update_scan_mode(struct iio_dev *indio_dev, 989 const unsigned long *scan_mask) 990 { 991 struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); 992 993 adc->nconv = bitmap_weight(scan_mask, indio_dev->masklength); 994 adc->smask = *scan_mask; 995 996 dev_dbg(&indio_dev->dev, "nconv=%d mask=%lx\n", adc->nconv, *scan_mask); 997 998 return 0; 999 } 1000 1001 static int stm32_dfsdm_postenable(struct iio_dev *indio_dev) 1002 { 1003 struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); 1004 int ret; 1005 1006 /* Reset adc buffer index */ 1007 adc->bufi = 0; 1008 1009 if (adc->hwc) { 1010 ret = iio_hw_consumer_enable(adc->hwc); 1011 if (ret < 0) 1012 return ret; 1013 } 1014 1015 ret = stm32_dfsdm_start_dfsdm(adc->dfsdm); 1016 if (ret < 0) 1017 goto err_stop_hwc; 1018 1019 ret = stm32_dfsdm_adc_dma_start(indio_dev); 1020 if (ret) { 1021 dev_err(&indio_dev->dev, "Can't start DMA\n"); 1022 goto stop_dfsdm; 1023 } 1024 1025 ret = stm32_dfsdm_start_conv(indio_dev, indio_dev->trig); 1026 if (ret) { 1027 dev_err(&indio_dev->dev, "Can't start conversion\n"); 1028 goto err_stop_dma; 1029 } 1030 1031 return 0; 1032 1033 err_stop_dma: 1034 stm32_dfsdm_adc_dma_stop(indio_dev); 1035 stop_dfsdm: 1036 stm32_dfsdm_stop_dfsdm(adc->dfsdm); 1037 err_stop_hwc: 1038 if (adc->hwc) 1039 iio_hw_consumer_disable(adc->hwc); 1040 1041 return ret; 1042 } 1043 1044 static int stm32_dfsdm_predisable(struct iio_dev *indio_dev) 1045 { 1046 struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); 1047 1048 stm32_dfsdm_stop_conv(indio_dev); 1049 1050 stm32_dfsdm_adc_dma_stop(indio_dev); 1051 1052 stm32_dfsdm_stop_dfsdm(adc->dfsdm); 1053 1054 if (adc->hwc) 1055 iio_hw_consumer_disable(adc->hwc); 1056 1057 return 0; 1058 } 1059 1060 static const struct iio_buffer_setup_ops stm32_dfsdm_buffer_setup_ops = { 1061 .postenable = &stm32_dfsdm_postenable, 1062 .predisable = &stm32_dfsdm_predisable, 1063 }; 1064 1065 /** 1066 * stm32_dfsdm_get_buff_cb() - register a callback that will be called when 1067 * DMA transfer period is achieved. 1068 * 1069 * @iio_dev: Handle to IIO device. 1070 * @cb: Pointer to callback function: 1071 * - data: pointer to data buffer 1072 * - size: size in byte of the data buffer 1073 * - private: pointer to consumer private structure. 1074 * @private: Pointer to consumer private structure. 1075 */ 1076 int stm32_dfsdm_get_buff_cb(struct iio_dev *iio_dev, 1077 int (*cb)(const void *data, size_t size, 1078 void *private), 1079 void *private) 1080 { 1081 struct stm32_dfsdm_adc *adc; 1082 1083 if (!iio_dev) 1084 return -EINVAL; 1085 adc = iio_priv(iio_dev); 1086 1087 adc->cb = cb; 1088 adc->cb_priv = private; 1089 1090 return 0; 1091 } 1092 EXPORT_SYMBOL_GPL(stm32_dfsdm_get_buff_cb); 1093 1094 /** 1095 * stm32_dfsdm_release_buff_cb - unregister buffer callback 1096 * 1097 * @iio_dev: Handle to IIO device. 1098 */ 1099 int stm32_dfsdm_release_buff_cb(struct iio_dev *iio_dev) 1100 { 1101 struct stm32_dfsdm_adc *adc; 1102 1103 if (!iio_dev) 1104 return -EINVAL; 1105 adc = iio_priv(iio_dev); 1106 1107 adc->cb = NULL; 1108 adc->cb_priv = NULL; 1109 1110 return 0; 1111 } 1112 EXPORT_SYMBOL_GPL(stm32_dfsdm_release_buff_cb); 1113 1114 static int stm32_dfsdm_single_conv(struct iio_dev *indio_dev, 1115 const struct iio_chan_spec *chan, int *res) 1116 { 1117 struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); 1118 long timeout; 1119 int ret; 1120 1121 reinit_completion(&adc->completion); 1122 1123 adc->buffer = res; 1124 1125 ret = stm32_dfsdm_start_dfsdm(adc->dfsdm); 1126 if (ret < 0) 1127 return ret; 1128 1129 ret = regmap_update_bits(adc->dfsdm->regmap, DFSDM_CR2(adc->fl_id), 1130 DFSDM_CR2_REOCIE_MASK, DFSDM_CR2_REOCIE(1)); 1131 if (ret < 0) 1132 goto stop_dfsdm; 1133 1134 adc->nconv = 1; 1135 adc->smask = BIT(chan->scan_index); 1136 ret = stm32_dfsdm_start_conv(indio_dev, NULL); 1137 if (ret < 0) { 1138 regmap_update_bits(adc->dfsdm->regmap, DFSDM_CR2(adc->fl_id), 1139 DFSDM_CR2_REOCIE_MASK, DFSDM_CR2_REOCIE(0)); 1140 goto stop_dfsdm; 1141 } 1142 1143 timeout = wait_for_completion_interruptible_timeout(&adc->completion, 1144 DFSDM_TIMEOUT); 1145 1146 /* Mask IRQ for regular conversion achievement*/ 1147 regmap_update_bits(adc->dfsdm->regmap, DFSDM_CR2(adc->fl_id), 1148 DFSDM_CR2_REOCIE_MASK, DFSDM_CR2_REOCIE(0)); 1149 1150 if (timeout == 0) 1151 ret = -ETIMEDOUT; 1152 else if (timeout < 0) 1153 ret = timeout; 1154 else 1155 ret = IIO_VAL_INT; 1156 1157 stm32_dfsdm_stop_conv(indio_dev); 1158 1159 stm32_dfsdm_process_data(adc, res); 1160 1161 stop_dfsdm: 1162 stm32_dfsdm_stop_dfsdm(adc->dfsdm); 1163 1164 return ret; 1165 } 1166 1167 static int stm32_dfsdm_write_raw(struct iio_dev *indio_dev, 1168 struct iio_chan_spec const *chan, 1169 int val, int val2, long mask) 1170 { 1171 struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); 1172 struct stm32_dfsdm_channel *ch = &adc->dfsdm->ch_list[chan->channel]; 1173 unsigned int spi_freq; 1174 int ret = -EINVAL; 1175 1176 switch (ch->src) { 1177 case DFSDM_CHANNEL_SPI_CLOCK_INTERNAL: 1178 spi_freq = adc->dfsdm->spi_master_freq; 1179 break; 1180 case DFSDM_CHANNEL_SPI_CLOCK_INTERNAL_DIV2_FALLING: 1181 case DFSDM_CHANNEL_SPI_CLOCK_INTERNAL_DIV2_RISING: 1182 spi_freq = adc->dfsdm->spi_master_freq / 2; 1183 break; 1184 default: 1185 spi_freq = adc->spi_freq; 1186 } 1187 1188 switch (mask) { 1189 case IIO_CHAN_INFO_OVERSAMPLING_RATIO: 1190 ret = iio_device_claim_direct_mode(indio_dev); 1191 if (ret) 1192 return ret; 1193 1194 ret = stm32_dfsdm_compute_all_osrs(indio_dev, val); 1195 if (!ret) { 1196 dev_dbg(&indio_dev->dev, 1197 "Sampling rate changed from (%u) to (%u)\n", 1198 adc->sample_freq, spi_freq / val); 1199 adc->oversamp = val; 1200 adc->sample_freq = spi_freq / val; 1201 } 1202 iio_device_release_direct_mode(indio_dev); 1203 return ret; 1204 1205 case IIO_CHAN_INFO_SAMP_FREQ: 1206 if (!val) 1207 return -EINVAL; 1208 1209 ret = iio_device_claim_direct_mode(indio_dev); 1210 if (ret) 1211 return ret; 1212 1213 ret = dfsdm_adc_set_samp_freq(indio_dev, val, spi_freq); 1214 iio_device_release_direct_mode(indio_dev); 1215 return ret; 1216 } 1217 1218 return -EINVAL; 1219 } 1220 1221 static int stm32_dfsdm_read_raw(struct iio_dev *indio_dev, 1222 struct iio_chan_spec const *chan, int *val, 1223 int *val2, long mask) 1224 { 1225 struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); 1226 int ret; 1227 1228 switch (mask) { 1229 case IIO_CHAN_INFO_RAW: 1230 ret = iio_device_claim_direct_mode(indio_dev); 1231 if (ret) 1232 return ret; 1233 ret = iio_hw_consumer_enable(adc->hwc); 1234 if (ret < 0) { 1235 dev_err(&indio_dev->dev, 1236 "%s: IIO enable failed (channel %d)\n", 1237 __func__, chan->channel); 1238 iio_device_release_direct_mode(indio_dev); 1239 return ret; 1240 } 1241 ret = stm32_dfsdm_single_conv(indio_dev, chan, val); 1242 iio_hw_consumer_disable(adc->hwc); 1243 if (ret < 0) { 1244 dev_err(&indio_dev->dev, 1245 "%s: Conversion failed (channel %d)\n", 1246 __func__, chan->channel); 1247 iio_device_release_direct_mode(indio_dev); 1248 return ret; 1249 } 1250 iio_device_release_direct_mode(indio_dev); 1251 return IIO_VAL_INT; 1252 1253 case IIO_CHAN_INFO_OVERSAMPLING_RATIO: 1254 *val = adc->oversamp; 1255 1256 return IIO_VAL_INT; 1257 1258 case IIO_CHAN_INFO_SAMP_FREQ: 1259 *val = adc->sample_freq; 1260 1261 return IIO_VAL_INT; 1262 } 1263 1264 return -EINVAL; 1265 } 1266 1267 static int stm32_dfsdm_validate_trigger(struct iio_dev *indio_dev, 1268 struct iio_trigger *trig) 1269 { 1270 return stm32_dfsdm_get_jextsel(indio_dev, trig) < 0 ? -EINVAL : 0; 1271 } 1272 1273 static const struct iio_info stm32_dfsdm_info_audio = { 1274 .hwfifo_set_watermark = stm32_dfsdm_set_watermark, 1275 .read_raw = stm32_dfsdm_read_raw, 1276 .write_raw = stm32_dfsdm_write_raw, 1277 .update_scan_mode = stm32_dfsdm_update_scan_mode, 1278 }; 1279 1280 static const struct iio_info stm32_dfsdm_info_adc = { 1281 .hwfifo_set_watermark = stm32_dfsdm_set_watermark, 1282 .read_raw = stm32_dfsdm_read_raw, 1283 .write_raw = stm32_dfsdm_write_raw, 1284 .update_scan_mode = stm32_dfsdm_update_scan_mode, 1285 .validate_trigger = stm32_dfsdm_validate_trigger, 1286 }; 1287 1288 static irqreturn_t stm32_dfsdm_irq(int irq, void *arg) 1289 { 1290 struct iio_dev *indio_dev = arg; 1291 struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); 1292 struct regmap *regmap = adc->dfsdm->regmap; 1293 unsigned int status, int_en; 1294 1295 regmap_read(regmap, DFSDM_ISR(adc->fl_id), &status); 1296 regmap_read(regmap, DFSDM_CR2(adc->fl_id), &int_en); 1297 1298 if (status & DFSDM_ISR_REOCF_MASK) { 1299 /* Read the data register clean the IRQ status */ 1300 regmap_read(regmap, DFSDM_RDATAR(adc->fl_id), adc->buffer); 1301 complete(&adc->completion); 1302 } 1303 1304 if (status & DFSDM_ISR_ROVRF_MASK) { 1305 if (int_en & DFSDM_CR2_ROVRIE_MASK) 1306 dev_warn(&indio_dev->dev, "Overrun detected\n"); 1307 regmap_update_bits(regmap, DFSDM_ICR(adc->fl_id), 1308 DFSDM_ICR_CLRROVRF_MASK, 1309 DFSDM_ICR_CLRROVRF_MASK); 1310 } 1311 1312 return IRQ_HANDLED; 1313 } 1314 1315 /* 1316 * Define external info for SPI Frequency and audio sampling rate that can be 1317 * configured by ASoC driver through consumer.h API 1318 */ 1319 static const struct iio_chan_spec_ext_info dfsdm_adc_audio_ext_info[] = { 1320 /* spi_clk_freq : clock freq on SPI/manchester bus used by channel */ 1321 { 1322 .name = "spi_clk_freq", 1323 .shared = IIO_SHARED_BY_TYPE, 1324 .read = dfsdm_adc_audio_get_spiclk, 1325 .write = dfsdm_adc_audio_set_spiclk, 1326 }, 1327 {}, 1328 }; 1329 1330 static void stm32_dfsdm_dma_release(struct iio_dev *indio_dev) 1331 { 1332 struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); 1333 1334 if (adc->dma_chan) { 1335 dma_free_coherent(adc->dma_chan->device->dev, 1336 DFSDM_DMA_BUFFER_SIZE, 1337 adc->rx_buf, adc->dma_buf); 1338 dma_release_channel(adc->dma_chan); 1339 } 1340 } 1341 1342 static int stm32_dfsdm_dma_request(struct device *dev, 1343 struct iio_dev *indio_dev) 1344 { 1345 struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); 1346 1347 adc->dma_chan = dma_request_chan(dev, "rx"); 1348 if (IS_ERR(adc->dma_chan)) { 1349 int ret = PTR_ERR(adc->dma_chan); 1350 1351 adc->dma_chan = NULL; 1352 return ret; 1353 } 1354 1355 adc->rx_buf = dma_alloc_coherent(adc->dma_chan->device->dev, 1356 DFSDM_DMA_BUFFER_SIZE, 1357 &adc->dma_buf, GFP_KERNEL); 1358 if (!adc->rx_buf) { 1359 dma_release_channel(adc->dma_chan); 1360 return -ENOMEM; 1361 } 1362 1363 indio_dev->modes |= INDIO_BUFFER_SOFTWARE; 1364 indio_dev->setup_ops = &stm32_dfsdm_buffer_setup_ops; 1365 1366 return 0; 1367 } 1368 1369 static int stm32_dfsdm_adc_chan_init_one(struct iio_dev *indio_dev, 1370 struct iio_chan_spec *ch) 1371 { 1372 struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); 1373 int ret; 1374 1375 ret = stm32_dfsdm_channel_parse_of(adc->dfsdm, indio_dev, ch); 1376 if (ret < 0) 1377 return ret; 1378 1379 ch->type = IIO_VOLTAGE; 1380 ch->indexed = 1; 1381 1382 /* 1383 * IIO_CHAN_INFO_RAW: used to compute regular conversion 1384 * IIO_CHAN_INFO_OVERSAMPLING_RATIO: used to set oversampling 1385 */ 1386 ch->info_mask_separate = BIT(IIO_CHAN_INFO_RAW); 1387 ch->info_mask_shared_by_all = BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO) | 1388 BIT(IIO_CHAN_INFO_SAMP_FREQ); 1389 1390 if (adc->dev_data->type == DFSDM_AUDIO) { 1391 ch->ext_info = dfsdm_adc_audio_ext_info; 1392 } else { 1393 ch->scan_type.shift = 8; 1394 } 1395 ch->scan_type.sign = 's'; 1396 ch->scan_type.realbits = 24; 1397 ch->scan_type.storagebits = 32; 1398 1399 return stm32_dfsdm_chan_configure(adc->dfsdm, 1400 &adc->dfsdm->ch_list[ch->channel]); 1401 } 1402 1403 static int stm32_dfsdm_audio_init(struct device *dev, struct iio_dev *indio_dev) 1404 { 1405 struct iio_chan_spec *ch; 1406 struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); 1407 struct stm32_dfsdm_channel *d_ch; 1408 int ret; 1409 1410 ch = devm_kzalloc(&indio_dev->dev, sizeof(*ch), GFP_KERNEL); 1411 if (!ch) 1412 return -ENOMEM; 1413 1414 ch->scan_index = 0; 1415 1416 ret = stm32_dfsdm_adc_chan_init_one(indio_dev, ch); 1417 if (ret < 0) { 1418 dev_err(&indio_dev->dev, "Channels init failed\n"); 1419 return ret; 1420 } 1421 ch->info_mask_separate = BIT(IIO_CHAN_INFO_SAMP_FREQ); 1422 1423 d_ch = &adc->dfsdm->ch_list[ch->channel]; 1424 if (d_ch->src != DFSDM_CHANNEL_SPI_CLOCK_EXTERNAL) 1425 adc->spi_freq = adc->dfsdm->spi_master_freq; 1426 1427 indio_dev->num_channels = 1; 1428 indio_dev->channels = ch; 1429 1430 return stm32_dfsdm_dma_request(dev, indio_dev); 1431 } 1432 1433 static int stm32_dfsdm_adc_init(struct device *dev, struct iio_dev *indio_dev) 1434 { 1435 struct iio_chan_spec *ch; 1436 struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); 1437 int num_ch; 1438 int ret, chan_idx; 1439 1440 adc->oversamp = DFSDM_DEFAULT_OVERSAMPLING; 1441 ret = stm32_dfsdm_compute_all_osrs(indio_dev, adc->oversamp); 1442 if (ret < 0) 1443 return ret; 1444 1445 num_ch = of_property_count_u32_elems(indio_dev->dev.of_node, 1446 "st,adc-channels"); 1447 if (num_ch < 0 || num_ch > adc->dfsdm->num_chs) { 1448 dev_err(&indio_dev->dev, "Bad st,adc-channels\n"); 1449 return num_ch < 0 ? num_ch : -EINVAL; 1450 } 1451 1452 /* Bind to SD modulator IIO device */ 1453 adc->hwc = devm_iio_hw_consumer_alloc(&indio_dev->dev); 1454 if (IS_ERR(adc->hwc)) 1455 return -EPROBE_DEFER; 1456 1457 ch = devm_kcalloc(&indio_dev->dev, num_ch, sizeof(*ch), 1458 GFP_KERNEL); 1459 if (!ch) 1460 return -ENOMEM; 1461 1462 for (chan_idx = 0; chan_idx < num_ch; chan_idx++) { 1463 ch[chan_idx].scan_index = chan_idx; 1464 ret = stm32_dfsdm_adc_chan_init_one(indio_dev, &ch[chan_idx]); 1465 if (ret < 0) { 1466 dev_err(&indio_dev->dev, "Channels init failed\n"); 1467 return ret; 1468 } 1469 } 1470 1471 indio_dev->num_channels = num_ch; 1472 indio_dev->channels = ch; 1473 1474 init_completion(&adc->completion); 1475 1476 /* Optionally request DMA */ 1477 ret = stm32_dfsdm_dma_request(dev, indio_dev); 1478 if (ret) { 1479 if (ret != -ENODEV) 1480 return dev_err_probe(dev, ret, 1481 "DMA channel request failed with\n"); 1482 1483 dev_dbg(dev, "No DMA support\n"); 1484 return 0; 1485 } 1486 1487 ret = iio_triggered_buffer_setup(indio_dev, 1488 &iio_pollfunc_store_time, NULL, 1489 &stm32_dfsdm_buffer_setup_ops); 1490 if (ret) { 1491 stm32_dfsdm_dma_release(indio_dev); 1492 dev_err(&indio_dev->dev, "buffer setup failed\n"); 1493 return ret; 1494 } 1495 1496 /* lptimer/timer hardware triggers */ 1497 indio_dev->modes |= INDIO_HARDWARE_TRIGGERED; 1498 1499 return 0; 1500 } 1501 1502 static const struct stm32_dfsdm_dev_data stm32h7_dfsdm_adc_data = { 1503 .type = DFSDM_IIO, 1504 .init = stm32_dfsdm_adc_init, 1505 }; 1506 1507 static const struct stm32_dfsdm_dev_data stm32h7_dfsdm_audio_data = { 1508 .type = DFSDM_AUDIO, 1509 .init = stm32_dfsdm_audio_init, 1510 }; 1511 1512 static const struct of_device_id stm32_dfsdm_adc_match[] = { 1513 { 1514 .compatible = "st,stm32-dfsdm-adc", 1515 .data = &stm32h7_dfsdm_adc_data, 1516 }, 1517 { 1518 .compatible = "st,stm32-dfsdm-dmic", 1519 .data = &stm32h7_dfsdm_audio_data, 1520 }, 1521 {} 1522 }; 1523 1524 static int stm32_dfsdm_adc_probe(struct platform_device *pdev) 1525 { 1526 struct device *dev = &pdev->dev; 1527 struct stm32_dfsdm_adc *adc; 1528 struct device_node *np = dev->of_node; 1529 const struct stm32_dfsdm_dev_data *dev_data; 1530 struct iio_dev *iio; 1531 char *name; 1532 int ret, irq, val; 1533 1534 dev_data = of_device_get_match_data(dev); 1535 iio = devm_iio_device_alloc(dev, sizeof(*adc)); 1536 if (!iio) { 1537 dev_err(dev, "%s: Failed to allocate IIO\n", __func__); 1538 return -ENOMEM; 1539 } 1540 1541 adc = iio_priv(iio); 1542 adc->dfsdm = dev_get_drvdata(dev->parent); 1543 1544 iio->dev.of_node = np; 1545 iio->modes = INDIO_DIRECT_MODE; 1546 1547 platform_set_drvdata(pdev, iio); 1548 1549 ret = of_property_read_u32(dev->of_node, "reg", &adc->fl_id); 1550 if (ret != 0 || adc->fl_id >= adc->dfsdm->num_fls) { 1551 dev_err(dev, "Missing or bad reg property\n"); 1552 return -EINVAL; 1553 } 1554 1555 name = devm_kzalloc(dev, sizeof("dfsdm-adc0"), GFP_KERNEL); 1556 if (!name) 1557 return -ENOMEM; 1558 if (dev_data->type == DFSDM_AUDIO) { 1559 iio->info = &stm32_dfsdm_info_audio; 1560 snprintf(name, sizeof("dfsdm-pdm0"), "dfsdm-pdm%d", adc->fl_id); 1561 } else { 1562 iio->info = &stm32_dfsdm_info_adc; 1563 snprintf(name, sizeof("dfsdm-adc0"), "dfsdm-adc%d", adc->fl_id); 1564 } 1565 iio->name = name; 1566 1567 /* 1568 * In a first step IRQs generated for channels are not treated. 1569 * So IRQ associated to filter instance 0 is dedicated to the Filter 0. 1570 */ 1571 irq = platform_get_irq(pdev, 0); 1572 if (irq < 0) 1573 return irq; 1574 1575 ret = devm_request_irq(dev, irq, stm32_dfsdm_irq, 1576 0, pdev->name, iio); 1577 if (ret < 0) { 1578 dev_err(dev, "Failed to request IRQ\n"); 1579 return ret; 1580 } 1581 1582 ret = of_property_read_u32(dev->of_node, "st,filter-order", &val); 1583 if (ret < 0) { 1584 dev_err(dev, "Failed to set filter order\n"); 1585 return ret; 1586 } 1587 1588 adc->dfsdm->fl_list[adc->fl_id].ford = val; 1589 1590 ret = of_property_read_u32(dev->of_node, "st,filter0-sync", &val); 1591 if (!ret) 1592 adc->dfsdm->fl_list[adc->fl_id].sync_mode = val; 1593 1594 adc->dev_data = dev_data; 1595 ret = dev_data->init(dev, iio); 1596 if (ret < 0) 1597 return ret; 1598 1599 ret = iio_device_register(iio); 1600 if (ret < 0) 1601 goto err_cleanup; 1602 1603 if (dev_data->type == DFSDM_AUDIO) { 1604 ret = of_platform_populate(np, NULL, NULL, dev); 1605 if (ret < 0) { 1606 dev_err(dev, "Failed to find an audio DAI\n"); 1607 goto err_unregister; 1608 } 1609 } 1610 1611 return 0; 1612 1613 err_unregister: 1614 iio_device_unregister(iio); 1615 err_cleanup: 1616 stm32_dfsdm_dma_release(iio); 1617 1618 return ret; 1619 } 1620 1621 static int stm32_dfsdm_adc_remove(struct platform_device *pdev) 1622 { 1623 struct iio_dev *indio_dev = platform_get_drvdata(pdev); 1624 struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); 1625 1626 if (adc->dev_data->type == DFSDM_AUDIO) 1627 of_platform_depopulate(&pdev->dev); 1628 iio_device_unregister(indio_dev); 1629 stm32_dfsdm_dma_release(indio_dev); 1630 1631 return 0; 1632 } 1633 1634 static int stm32_dfsdm_adc_suspend(struct device *dev) 1635 { 1636 struct iio_dev *indio_dev = dev_get_drvdata(dev); 1637 1638 if (iio_buffer_enabled(indio_dev)) 1639 stm32_dfsdm_predisable(indio_dev); 1640 1641 return 0; 1642 } 1643 1644 static int stm32_dfsdm_adc_resume(struct device *dev) 1645 { 1646 struct iio_dev *indio_dev = dev_get_drvdata(dev); 1647 struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); 1648 const struct iio_chan_spec *chan; 1649 struct stm32_dfsdm_channel *ch; 1650 int i, ret; 1651 1652 /* restore channels configuration */ 1653 for (i = 0; i < indio_dev->num_channels; i++) { 1654 chan = indio_dev->channels + i; 1655 ch = &adc->dfsdm->ch_list[chan->channel]; 1656 ret = stm32_dfsdm_chan_configure(adc->dfsdm, ch); 1657 if (ret) 1658 return ret; 1659 } 1660 1661 if (iio_buffer_enabled(indio_dev)) 1662 stm32_dfsdm_postenable(indio_dev); 1663 1664 return 0; 1665 } 1666 1667 static DEFINE_SIMPLE_DEV_PM_OPS(stm32_dfsdm_adc_pm_ops, 1668 stm32_dfsdm_adc_suspend, 1669 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 = pm_sleep_ptr(&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