1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Driver for the Diolan DLN-2 USB-ADC adapter 4 * 5 * Copyright (c) 2017 Jack Andersen 6 */ 7 8 #include <linux/kernel.h> 9 #include <linux/module.h> 10 #include <linux/types.h> 11 #include <linux/platform_device.h> 12 #include <linux/mfd/dln2.h> 13 14 #include <linux/iio/iio.h> 15 #include <linux/iio/sysfs.h> 16 #include <linux/iio/trigger.h> 17 #include <linux/iio/trigger_consumer.h> 18 #include <linux/iio/triggered_buffer.h> 19 #include <linux/iio/buffer.h> 20 #include <linux/iio/kfifo_buf.h> 21 22 #define DLN2_ADC_MOD_NAME "dln2-adc" 23 24 #define DLN2_ADC_ID 0x06 25 26 #define DLN2_ADC_GET_CHANNEL_COUNT DLN2_CMD(0x01, DLN2_ADC_ID) 27 #define DLN2_ADC_ENABLE DLN2_CMD(0x02, DLN2_ADC_ID) 28 #define DLN2_ADC_DISABLE DLN2_CMD(0x03, DLN2_ADC_ID) 29 #define DLN2_ADC_CHANNEL_ENABLE DLN2_CMD(0x05, DLN2_ADC_ID) 30 #define DLN2_ADC_CHANNEL_DISABLE DLN2_CMD(0x06, DLN2_ADC_ID) 31 #define DLN2_ADC_SET_RESOLUTION DLN2_CMD(0x08, DLN2_ADC_ID) 32 #define DLN2_ADC_CHANNEL_GET_VAL DLN2_CMD(0x0A, DLN2_ADC_ID) 33 #define DLN2_ADC_CHANNEL_GET_ALL_VAL DLN2_CMD(0x0B, DLN2_ADC_ID) 34 #define DLN2_ADC_CHANNEL_SET_CFG DLN2_CMD(0x0C, DLN2_ADC_ID) 35 #define DLN2_ADC_CHANNEL_GET_CFG DLN2_CMD(0x0D, DLN2_ADC_ID) 36 #define DLN2_ADC_CONDITION_MET_EV DLN2_CMD(0x10, DLN2_ADC_ID) 37 38 #define DLN2_ADC_EVENT_NONE 0 39 #define DLN2_ADC_EVENT_BELOW 1 40 #define DLN2_ADC_EVENT_LEVEL_ABOVE 2 41 #define DLN2_ADC_EVENT_OUTSIDE 3 42 #define DLN2_ADC_EVENT_INSIDE 4 43 #define DLN2_ADC_EVENT_ALWAYS 5 44 45 #define DLN2_ADC_MAX_CHANNELS 8 46 #define DLN2_ADC_DATA_BITS 10 47 48 /* 49 * Plays similar role to iio_demux_table in subsystem core; except allocated 50 * in a fixed 8-element array. 51 */ 52 struct dln2_adc_demux_table { 53 unsigned int from; 54 unsigned int to; 55 unsigned int length; 56 }; 57 58 struct dln2_adc { 59 struct platform_device *pdev; 60 struct iio_chan_spec iio_channels[DLN2_ADC_MAX_CHANNELS + 1]; 61 int port, trigger_chan; 62 struct iio_trigger *trig; 63 struct mutex mutex; 64 /* Cached sample period in milliseconds */ 65 unsigned int sample_period; 66 /* Demux table */ 67 unsigned int demux_count; 68 struct dln2_adc_demux_table demux[DLN2_ADC_MAX_CHANNELS]; 69 /* Precomputed timestamp padding offset and length */ 70 unsigned int ts_pad_offset, ts_pad_length; 71 }; 72 73 struct dln2_adc_port_chan { 74 u8 port; 75 u8 chan; 76 }; 77 78 struct dln2_adc_get_all_vals { 79 __le16 channel_mask; 80 __le16 values[DLN2_ADC_MAX_CHANNELS]; 81 }; 82 83 static void dln2_adc_add_demux(struct dln2_adc *dln2, 84 unsigned int in_loc, unsigned int out_loc, 85 unsigned int length) 86 { 87 struct dln2_adc_demux_table *p = dln2->demux_count ? 88 &dln2->demux[dln2->demux_count - 1] : NULL; 89 90 if (p && p->from + p->length == in_loc && 91 p->to + p->length == out_loc) { 92 p->length += length; 93 } else if (dln2->demux_count < DLN2_ADC_MAX_CHANNELS) { 94 p = &dln2->demux[dln2->demux_count++]; 95 p->from = in_loc; 96 p->to = out_loc; 97 p->length = length; 98 } 99 } 100 101 static void dln2_adc_update_demux(struct dln2_adc *dln2) 102 { 103 int in_ind = -1, out_ind; 104 unsigned int in_loc = 0, out_loc = 0; 105 struct iio_dev *indio_dev = platform_get_drvdata(dln2->pdev); 106 107 /* Clear out any old demux */ 108 dln2->demux_count = 0; 109 110 /* Optimize all 8-channels case */ 111 if (indio_dev->masklength && 112 (*indio_dev->active_scan_mask & 0xff) == 0xff) { 113 dln2_adc_add_demux(dln2, 0, 0, 16); 114 dln2->ts_pad_offset = 0; 115 dln2->ts_pad_length = 0; 116 return; 117 } 118 119 /* Build demux table from fixed 8-channels to active_scan_mask */ 120 for_each_set_bit(out_ind, 121 indio_dev->active_scan_mask, 122 indio_dev->masklength) { 123 /* Handle timestamp separately */ 124 if (out_ind == DLN2_ADC_MAX_CHANNELS) 125 break; 126 for (++in_ind; in_ind != out_ind; ++in_ind) 127 in_loc += 2; 128 dln2_adc_add_demux(dln2, in_loc, out_loc, 2); 129 out_loc += 2; 130 in_loc += 2; 131 } 132 133 if (indio_dev->scan_timestamp) { 134 size_t ts_offset = indio_dev->scan_bytes / sizeof(int64_t) - 1; 135 136 dln2->ts_pad_offset = out_loc; 137 dln2->ts_pad_length = ts_offset * sizeof(int64_t) - out_loc; 138 } else { 139 dln2->ts_pad_offset = 0; 140 dln2->ts_pad_length = 0; 141 } 142 } 143 144 static int dln2_adc_get_chan_count(struct dln2_adc *dln2) 145 { 146 int ret; 147 u8 port = dln2->port; 148 u8 count; 149 int olen = sizeof(count); 150 151 ret = dln2_transfer(dln2->pdev, DLN2_ADC_GET_CHANNEL_COUNT, 152 &port, sizeof(port), &count, &olen); 153 if (ret < 0) { 154 dev_dbg(&dln2->pdev->dev, "Problem in %s\n", __func__); 155 return ret; 156 } 157 if (olen < sizeof(count)) 158 return -EPROTO; 159 160 return count; 161 } 162 163 static int dln2_adc_set_port_resolution(struct dln2_adc *dln2) 164 { 165 int ret; 166 struct dln2_adc_port_chan port_chan = { 167 .port = dln2->port, 168 .chan = DLN2_ADC_DATA_BITS, 169 }; 170 171 ret = dln2_transfer_tx(dln2->pdev, DLN2_ADC_SET_RESOLUTION, 172 &port_chan, sizeof(port_chan)); 173 if (ret < 0) 174 dev_dbg(&dln2->pdev->dev, "Problem in %s\n", __func__); 175 176 return ret; 177 } 178 179 static int dln2_adc_set_chan_enabled(struct dln2_adc *dln2, 180 int channel, bool enable) 181 { 182 int ret; 183 struct dln2_adc_port_chan port_chan = { 184 .port = dln2->port, 185 .chan = channel, 186 }; 187 u16 cmd = enable ? DLN2_ADC_CHANNEL_ENABLE : DLN2_ADC_CHANNEL_DISABLE; 188 189 ret = dln2_transfer_tx(dln2->pdev, cmd, &port_chan, sizeof(port_chan)); 190 if (ret < 0) 191 dev_dbg(&dln2->pdev->dev, "Problem in %s\n", __func__); 192 193 return ret; 194 } 195 196 static int dln2_adc_set_port_enabled(struct dln2_adc *dln2, bool enable, 197 u16 *conflict_out) 198 { 199 int ret; 200 u8 port = dln2->port; 201 __le16 conflict; 202 int olen = sizeof(conflict); 203 u16 cmd = enable ? DLN2_ADC_ENABLE : DLN2_ADC_DISABLE; 204 205 if (conflict_out) 206 *conflict_out = 0; 207 208 ret = dln2_transfer(dln2->pdev, cmd, &port, sizeof(port), 209 &conflict, &olen); 210 if (ret < 0) { 211 dev_dbg(&dln2->pdev->dev, "Problem in %s(%d)\n", 212 __func__, (int)enable); 213 if (conflict_out && enable && olen >= sizeof(conflict)) 214 *conflict_out = le16_to_cpu(conflict); 215 return ret; 216 } 217 if (enable && olen < sizeof(conflict)) 218 return -EPROTO; 219 220 return ret; 221 } 222 223 static int dln2_adc_set_chan_period(struct dln2_adc *dln2, 224 unsigned int channel, unsigned int period) 225 { 226 int ret; 227 struct { 228 struct dln2_adc_port_chan port_chan; 229 __u8 type; 230 __le16 period; 231 __le16 low; 232 __le16 high; 233 } __packed set_cfg = { 234 .port_chan.port = dln2->port, 235 .port_chan.chan = channel, 236 .type = period ? DLN2_ADC_EVENT_ALWAYS : DLN2_ADC_EVENT_NONE, 237 .period = cpu_to_le16(period) 238 }; 239 240 ret = dln2_transfer_tx(dln2->pdev, DLN2_ADC_CHANNEL_SET_CFG, 241 &set_cfg, sizeof(set_cfg)); 242 if (ret < 0) 243 dev_dbg(&dln2->pdev->dev, "Problem in %s\n", __func__); 244 245 return ret; 246 } 247 248 static int dln2_adc_read(struct dln2_adc *dln2, unsigned int channel) 249 { 250 int ret, i; 251 u16 conflict; 252 __le16 value; 253 int olen = sizeof(value); 254 struct dln2_adc_port_chan port_chan = { 255 .port = dln2->port, 256 .chan = channel, 257 }; 258 259 ret = dln2_adc_set_chan_enabled(dln2, channel, true); 260 if (ret < 0) 261 return ret; 262 263 ret = dln2_adc_set_port_enabled(dln2, true, &conflict); 264 if (ret < 0) { 265 if (conflict) { 266 dev_err(&dln2->pdev->dev, 267 "ADC pins conflict with mask %04X\n", 268 (int)conflict); 269 ret = -EBUSY; 270 } 271 goto disable_chan; 272 } 273 274 /* 275 * Call GET_VAL twice due to initial zero-return immediately after 276 * enabling channel. 277 */ 278 for (i = 0; i < 2; ++i) { 279 ret = dln2_transfer(dln2->pdev, DLN2_ADC_CHANNEL_GET_VAL, 280 &port_chan, sizeof(port_chan), 281 &value, &olen); 282 if (ret < 0) { 283 dev_dbg(&dln2->pdev->dev, "Problem in %s\n", __func__); 284 goto disable_port; 285 } 286 if (olen < sizeof(value)) { 287 ret = -EPROTO; 288 goto disable_port; 289 } 290 } 291 292 ret = le16_to_cpu(value); 293 294 disable_port: 295 dln2_adc_set_port_enabled(dln2, false, NULL); 296 disable_chan: 297 dln2_adc_set_chan_enabled(dln2, channel, false); 298 299 return ret; 300 } 301 302 static int dln2_adc_read_all(struct dln2_adc *dln2, 303 struct dln2_adc_get_all_vals *get_all_vals) 304 { 305 int ret; 306 __u8 port = dln2->port; 307 int olen = sizeof(*get_all_vals); 308 309 ret = dln2_transfer(dln2->pdev, DLN2_ADC_CHANNEL_GET_ALL_VAL, 310 &port, sizeof(port), get_all_vals, &olen); 311 if (ret < 0) { 312 dev_dbg(&dln2->pdev->dev, "Problem in %s\n", __func__); 313 return ret; 314 } 315 if (olen < sizeof(*get_all_vals)) 316 return -EPROTO; 317 318 return ret; 319 } 320 321 static int dln2_adc_read_raw(struct iio_dev *indio_dev, 322 struct iio_chan_spec const *chan, 323 int *val, 324 int *val2, 325 long mask) 326 { 327 int ret; 328 unsigned int microhertz; 329 struct dln2_adc *dln2 = iio_priv(indio_dev); 330 331 switch (mask) { 332 case IIO_CHAN_INFO_RAW: 333 ret = iio_device_claim_direct_mode(indio_dev); 334 if (ret < 0) 335 return ret; 336 337 mutex_lock(&dln2->mutex); 338 ret = dln2_adc_read(dln2, chan->channel); 339 mutex_unlock(&dln2->mutex); 340 341 iio_device_release_direct_mode(indio_dev); 342 343 if (ret < 0) 344 return ret; 345 346 *val = ret; 347 return IIO_VAL_INT; 348 349 case IIO_CHAN_INFO_SCALE: 350 /* 351 * Voltage reference is fixed at 3.3v 352 * 3.3 / (1 << 10) * 1000000000 353 */ 354 *val = 0; 355 *val2 = 3222656; 356 return IIO_VAL_INT_PLUS_NANO; 357 358 case IIO_CHAN_INFO_SAMP_FREQ: 359 if (dln2->sample_period) { 360 microhertz = 1000000000 / dln2->sample_period; 361 *val = microhertz / 1000000; 362 *val2 = microhertz % 1000000; 363 } else { 364 *val = 0; 365 *val2 = 0; 366 } 367 368 return IIO_VAL_INT_PLUS_MICRO; 369 370 default: 371 return -EINVAL; 372 } 373 } 374 375 static int dln2_adc_write_raw(struct iio_dev *indio_dev, 376 struct iio_chan_spec const *chan, 377 int val, 378 int val2, 379 long mask) 380 { 381 int ret; 382 unsigned int microhertz; 383 struct dln2_adc *dln2 = iio_priv(indio_dev); 384 385 switch (mask) { 386 case IIO_CHAN_INFO_SAMP_FREQ: 387 microhertz = 1000000 * val + val2; 388 389 mutex_lock(&dln2->mutex); 390 391 dln2->sample_period = 392 microhertz ? 1000000000 / microhertz : UINT_MAX; 393 if (dln2->sample_period > 65535) { 394 dln2->sample_period = 65535; 395 dev_warn(&dln2->pdev->dev, 396 "clamping period to 65535ms\n"); 397 } 398 399 /* 400 * The first requested channel is arbitrated as a shared 401 * trigger source, so only one event is registered with the 402 * DLN. The event handler will then read all enabled channel 403 * values using DLN2_ADC_CHANNEL_GET_ALL_VAL to maintain 404 * synchronization between ADC readings. 405 */ 406 if (dln2->trigger_chan != -1) 407 ret = dln2_adc_set_chan_period(dln2, 408 dln2->trigger_chan, dln2->sample_period); 409 else 410 ret = 0; 411 412 mutex_unlock(&dln2->mutex); 413 414 return ret; 415 416 default: 417 return -EINVAL; 418 } 419 } 420 421 static int dln2_update_scan_mode(struct iio_dev *indio_dev, 422 const unsigned long *scan_mask) 423 { 424 struct dln2_adc *dln2 = iio_priv(indio_dev); 425 int chan_count = indio_dev->num_channels - 1; 426 int ret, i, j; 427 428 mutex_lock(&dln2->mutex); 429 430 for (i = 0; i < chan_count; ++i) { 431 ret = dln2_adc_set_chan_enabled(dln2, i, 432 test_bit(i, scan_mask)); 433 if (ret < 0) { 434 for (j = 0; j < i; ++j) 435 dln2_adc_set_chan_enabled(dln2, j, false); 436 mutex_unlock(&dln2->mutex); 437 dev_err(&dln2->pdev->dev, 438 "Unable to enable ADC channel %d\n", i); 439 return -EBUSY; 440 } 441 } 442 443 dln2_adc_update_demux(dln2); 444 445 mutex_unlock(&dln2->mutex); 446 447 return 0; 448 } 449 450 #define DLN2_ADC_CHAN(lval, idx) { \ 451 lval.type = IIO_VOLTAGE; \ 452 lval.channel = idx; \ 453 lval.indexed = 1; \ 454 lval.info_mask_separate = BIT(IIO_CHAN_INFO_RAW); \ 455 lval.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SCALE) | \ 456 BIT(IIO_CHAN_INFO_SAMP_FREQ); \ 457 lval.scan_index = idx; \ 458 lval.scan_type.sign = 'u'; \ 459 lval.scan_type.realbits = DLN2_ADC_DATA_BITS; \ 460 lval.scan_type.storagebits = 16; \ 461 lval.scan_type.endianness = IIO_LE; \ 462 } 463 464 /* Assignment version of IIO_CHAN_SOFT_TIMESTAMP */ 465 #define IIO_CHAN_SOFT_TIMESTAMP_ASSIGN(lval, _si) { \ 466 lval.type = IIO_TIMESTAMP; \ 467 lval.channel = -1; \ 468 lval.scan_index = _si; \ 469 lval.scan_type.sign = 's'; \ 470 lval.scan_type.realbits = 64; \ 471 lval.scan_type.storagebits = 64; \ 472 } 473 474 static const struct iio_info dln2_adc_info = { 475 .read_raw = dln2_adc_read_raw, 476 .write_raw = dln2_adc_write_raw, 477 .update_scan_mode = dln2_update_scan_mode, 478 }; 479 480 static irqreturn_t dln2_adc_trigger_h(int irq, void *p) 481 { 482 struct iio_poll_func *pf = p; 483 struct iio_dev *indio_dev = pf->indio_dev; 484 struct { 485 __le16 values[DLN2_ADC_MAX_CHANNELS]; 486 int64_t timestamp_space; 487 } data; 488 struct dln2_adc_get_all_vals dev_data; 489 struct dln2_adc *dln2 = iio_priv(indio_dev); 490 const struct dln2_adc_demux_table *t; 491 int ret, i; 492 493 mutex_lock(&dln2->mutex); 494 ret = dln2_adc_read_all(dln2, &dev_data); 495 mutex_unlock(&dln2->mutex); 496 if (ret < 0) 497 goto done; 498 499 /* Demux operation */ 500 for (i = 0; i < dln2->demux_count; ++i) { 501 t = &dln2->demux[i]; 502 memcpy((void *)data.values + t->to, 503 (void *)dev_data.values + t->from, t->length); 504 } 505 506 /* Zero padding space between values and timestamp */ 507 if (dln2->ts_pad_length) 508 memset((void *)data.values + dln2->ts_pad_offset, 509 0, dln2->ts_pad_length); 510 511 iio_push_to_buffers_with_timestamp(indio_dev, &data, 512 iio_get_time_ns(indio_dev)); 513 514 done: 515 iio_trigger_notify_done(indio_dev->trig); 516 return IRQ_HANDLED; 517 } 518 519 static int dln2_adc_triggered_buffer_postenable(struct iio_dev *indio_dev) 520 { 521 int ret; 522 struct dln2_adc *dln2 = iio_priv(indio_dev); 523 u16 conflict; 524 unsigned int trigger_chan; 525 526 mutex_lock(&dln2->mutex); 527 528 /* Enable ADC */ 529 ret = dln2_adc_set_port_enabled(dln2, true, &conflict); 530 if (ret < 0) { 531 mutex_unlock(&dln2->mutex); 532 dev_dbg(&dln2->pdev->dev, "Problem in %s\n", __func__); 533 if (conflict) { 534 dev_err(&dln2->pdev->dev, 535 "ADC pins conflict with mask %04X\n", 536 (int)conflict); 537 ret = -EBUSY; 538 } 539 return ret; 540 } 541 542 /* Assign trigger channel based on first enabled channel */ 543 trigger_chan = find_first_bit(indio_dev->active_scan_mask, 544 indio_dev->masklength); 545 if (trigger_chan < DLN2_ADC_MAX_CHANNELS) { 546 dln2->trigger_chan = trigger_chan; 547 ret = dln2_adc_set_chan_period(dln2, dln2->trigger_chan, 548 dln2->sample_period); 549 mutex_unlock(&dln2->mutex); 550 if (ret < 0) { 551 dev_dbg(&dln2->pdev->dev, "Problem in %s\n", __func__); 552 return ret; 553 } 554 } else { 555 dln2->trigger_chan = -1; 556 mutex_unlock(&dln2->mutex); 557 } 558 559 return 0; 560 } 561 562 static int dln2_adc_triggered_buffer_predisable(struct iio_dev *indio_dev) 563 { 564 int ret; 565 struct dln2_adc *dln2 = iio_priv(indio_dev); 566 567 mutex_lock(&dln2->mutex); 568 569 /* Disable trigger channel */ 570 if (dln2->trigger_chan != -1) { 571 dln2_adc_set_chan_period(dln2, dln2->trigger_chan, 0); 572 dln2->trigger_chan = -1; 573 } 574 575 /* Disable ADC */ 576 ret = dln2_adc_set_port_enabled(dln2, false, NULL); 577 578 mutex_unlock(&dln2->mutex); 579 if (ret < 0) 580 dev_dbg(&dln2->pdev->dev, "Problem in %s\n", __func__); 581 582 return ret; 583 } 584 585 static const struct iio_buffer_setup_ops dln2_adc_buffer_setup_ops = { 586 .postenable = dln2_adc_triggered_buffer_postenable, 587 .predisable = dln2_adc_triggered_buffer_predisable, 588 }; 589 590 static void dln2_adc_event(struct platform_device *pdev, u16 echo, 591 const void *data, int len) 592 { 593 struct iio_dev *indio_dev = platform_get_drvdata(pdev); 594 struct dln2_adc *dln2 = iio_priv(indio_dev); 595 596 /* Called via URB completion handler */ 597 iio_trigger_poll(dln2->trig); 598 } 599 600 static int dln2_adc_probe(struct platform_device *pdev) 601 { 602 struct device *dev = &pdev->dev; 603 struct dln2_adc *dln2; 604 struct dln2_platform_data *pdata = dev_get_platdata(&pdev->dev); 605 struct iio_dev *indio_dev; 606 int i, ret, chans; 607 608 indio_dev = devm_iio_device_alloc(dev, sizeof(*dln2)); 609 if (!indio_dev) { 610 dev_err(dev, "failed allocating iio device\n"); 611 return -ENOMEM; 612 } 613 614 dln2 = iio_priv(indio_dev); 615 dln2->pdev = pdev; 616 dln2->port = pdata->port; 617 dln2->trigger_chan = -1; 618 mutex_init(&dln2->mutex); 619 620 platform_set_drvdata(pdev, indio_dev); 621 622 ret = dln2_adc_set_port_resolution(dln2); 623 if (ret < 0) { 624 dev_err(dev, "failed to set ADC resolution to 10 bits\n"); 625 return ret; 626 } 627 628 chans = dln2_adc_get_chan_count(dln2); 629 if (chans < 0) { 630 dev_err(dev, "failed to get channel count: %d\n", chans); 631 return chans; 632 } 633 if (chans > DLN2_ADC_MAX_CHANNELS) { 634 chans = DLN2_ADC_MAX_CHANNELS; 635 dev_warn(dev, "clamping channels to %d\n", 636 DLN2_ADC_MAX_CHANNELS); 637 } 638 639 for (i = 0; i < chans; ++i) 640 DLN2_ADC_CHAN(dln2->iio_channels[i], i) 641 IIO_CHAN_SOFT_TIMESTAMP_ASSIGN(dln2->iio_channels[i], i); 642 643 indio_dev->name = DLN2_ADC_MOD_NAME; 644 indio_dev->info = &dln2_adc_info; 645 indio_dev->modes = INDIO_DIRECT_MODE; 646 indio_dev->channels = dln2->iio_channels; 647 indio_dev->num_channels = chans + 1; 648 indio_dev->setup_ops = &dln2_adc_buffer_setup_ops; 649 650 dln2->trig = devm_iio_trigger_alloc(dev, "%s-dev%d", 651 indio_dev->name, 652 iio_device_id(indio_dev)); 653 if (!dln2->trig) { 654 dev_err(dev, "failed to allocate trigger\n"); 655 return -ENOMEM; 656 } 657 iio_trigger_set_drvdata(dln2->trig, dln2); 658 ret = devm_iio_trigger_register(dev, dln2->trig); 659 if (ret) { 660 dev_err(dev, "failed to register trigger: %d\n", ret); 661 return ret; 662 } 663 iio_trigger_set_immutable(indio_dev, dln2->trig); 664 665 ret = devm_iio_triggered_buffer_setup(dev, indio_dev, NULL, 666 dln2_adc_trigger_h, 667 &dln2_adc_buffer_setup_ops); 668 if (ret) { 669 dev_err(dev, "failed to allocate triggered buffer: %d\n", ret); 670 return ret; 671 } 672 673 ret = dln2_register_event_cb(pdev, DLN2_ADC_CONDITION_MET_EV, 674 dln2_adc_event); 675 if (ret) { 676 dev_err(dev, "failed to setup DLN2 periodic event: %d\n", ret); 677 return ret; 678 } 679 680 ret = iio_device_register(indio_dev); 681 if (ret) { 682 dev_err(dev, "failed to register iio device: %d\n", ret); 683 goto unregister_event; 684 } 685 686 return ret; 687 688 unregister_event: 689 dln2_unregister_event_cb(pdev, DLN2_ADC_CONDITION_MET_EV); 690 691 return ret; 692 } 693 694 static int dln2_adc_remove(struct platform_device *pdev) 695 { 696 struct iio_dev *indio_dev = platform_get_drvdata(pdev); 697 698 iio_device_unregister(indio_dev); 699 dln2_unregister_event_cb(pdev, DLN2_ADC_CONDITION_MET_EV); 700 return 0; 701 } 702 703 static struct platform_driver dln2_adc_driver = { 704 .driver.name = DLN2_ADC_MOD_NAME, 705 .probe = dln2_adc_probe, 706 .remove = dln2_adc_remove, 707 }; 708 709 module_platform_driver(dln2_adc_driver); 710 711 MODULE_AUTHOR("Jack Andersen <jackoalan@gmail.com"); 712 MODULE_DESCRIPTION("Driver for the Diolan DLN2 ADC interface"); 713 MODULE_LICENSE("GPL v2"); 714 MODULE_ALIAS("platform:dln2-adc"); 715