1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * STM32 Low-Power Timer Encoder and Counter driver 4 * 5 * Copyright (C) STMicroelectronics 2017 6 * 7 * Author: Fabrice Gasnier <fabrice.gasnier@st.com> 8 * 9 * Inspired by 104-quad-8 and stm32-timer-trigger drivers. 10 * 11 */ 12 13 #include <linux/bitfield.h> 14 #include <linux/counter.h> 15 #include <linux/iio/iio.h> 16 #include <linux/mfd/stm32-lptimer.h> 17 #include <linux/module.h> 18 #include <linux/pinctrl/consumer.h> 19 #include <linux/platform_device.h> 20 21 struct stm32_lptim_cnt { 22 struct counter_device counter; 23 struct device *dev; 24 struct regmap *regmap; 25 struct clk *clk; 26 u32 ceiling; 27 u32 polarity; 28 u32 quadrature_mode; 29 bool enabled; 30 }; 31 32 static int stm32_lptim_is_enabled(struct stm32_lptim_cnt *priv) 33 { 34 u32 val; 35 int ret; 36 37 ret = regmap_read(priv->regmap, STM32_LPTIM_CR, &val); 38 if (ret) 39 return ret; 40 41 return FIELD_GET(STM32_LPTIM_ENABLE, val); 42 } 43 44 static int stm32_lptim_set_enable_state(struct stm32_lptim_cnt *priv, 45 int enable) 46 { 47 int ret; 48 u32 val; 49 50 val = FIELD_PREP(STM32_LPTIM_ENABLE, enable); 51 ret = regmap_write(priv->regmap, STM32_LPTIM_CR, val); 52 if (ret) 53 return ret; 54 55 if (!enable) { 56 clk_disable(priv->clk); 57 priv->enabled = false; 58 return 0; 59 } 60 61 /* LP timer must be enabled before writing CMP & ARR */ 62 ret = regmap_write(priv->regmap, STM32_LPTIM_ARR, priv->ceiling); 63 if (ret) 64 return ret; 65 66 ret = regmap_write(priv->regmap, STM32_LPTIM_CMP, 0); 67 if (ret) 68 return ret; 69 70 /* ensure CMP & ARR registers are properly written */ 71 ret = regmap_read_poll_timeout(priv->regmap, STM32_LPTIM_ISR, val, 72 (val & STM32_LPTIM_CMPOK_ARROK), 73 100, 1000); 74 if (ret) 75 return ret; 76 77 ret = regmap_write(priv->regmap, STM32_LPTIM_ICR, 78 STM32_LPTIM_CMPOKCF_ARROKCF); 79 if (ret) 80 return ret; 81 82 ret = clk_enable(priv->clk); 83 if (ret) { 84 regmap_write(priv->regmap, STM32_LPTIM_CR, 0); 85 return ret; 86 } 87 priv->enabled = true; 88 89 /* Start LP timer in continuous mode */ 90 return regmap_update_bits(priv->regmap, STM32_LPTIM_CR, 91 STM32_LPTIM_CNTSTRT, STM32_LPTIM_CNTSTRT); 92 } 93 94 static int stm32_lptim_setup(struct stm32_lptim_cnt *priv, int enable) 95 { 96 u32 mask = STM32_LPTIM_ENC | STM32_LPTIM_COUNTMODE | 97 STM32_LPTIM_CKPOL | STM32_LPTIM_PRESC; 98 u32 val; 99 100 /* Setup LP timer encoder/counter and polarity, without prescaler */ 101 if (priv->quadrature_mode) 102 val = enable ? STM32_LPTIM_ENC : 0; 103 else 104 val = enable ? STM32_LPTIM_COUNTMODE : 0; 105 val |= FIELD_PREP(STM32_LPTIM_CKPOL, enable ? priv->polarity : 0); 106 107 return regmap_update_bits(priv->regmap, STM32_LPTIM_CFGR, mask, val); 108 } 109 110 static int stm32_lptim_write_raw(struct iio_dev *indio_dev, 111 struct iio_chan_spec const *chan, 112 int val, int val2, long mask) 113 { 114 struct stm32_lptim_cnt *priv = iio_priv(indio_dev); 115 int ret; 116 117 switch (mask) { 118 case IIO_CHAN_INFO_ENABLE: 119 if (val < 0 || val > 1) 120 return -EINVAL; 121 122 /* Check nobody uses the timer, or already disabled/enabled */ 123 ret = stm32_lptim_is_enabled(priv); 124 if ((ret < 0) || (!ret && !val)) 125 return ret; 126 if (val && ret) 127 return -EBUSY; 128 129 ret = stm32_lptim_setup(priv, val); 130 if (ret) 131 return ret; 132 return stm32_lptim_set_enable_state(priv, val); 133 134 default: 135 return -EINVAL; 136 } 137 } 138 139 static int stm32_lptim_read_raw(struct iio_dev *indio_dev, 140 struct iio_chan_spec const *chan, 141 int *val, int *val2, long mask) 142 { 143 struct stm32_lptim_cnt *priv = iio_priv(indio_dev); 144 u32 dat; 145 int ret; 146 147 switch (mask) { 148 case IIO_CHAN_INFO_RAW: 149 ret = regmap_read(priv->regmap, STM32_LPTIM_CNT, &dat); 150 if (ret) 151 return ret; 152 *val = dat; 153 return IIO_VAL_INT; 154 155 case IIO_CHAN_INFO_ENABLE: 156 ret = stm32_lptim_is_enabled(priv); 157 if (ret < 0) 158 return ret; 159 *val = ret; 160 return IIO_VAL_INT; 161 162 case IIO_CHAN_INFO_SCALE: 163 /* Non-quadrature mode: scale = 1 */ 164 *val = 1; 165 *val2 = 0; 166 if (priv->quadrature_mode) { 167 /* 168 * Quadrature encoder mode: 169 * - both edges, quarter cycle, scale is 0.25 170 * - either rising/falling edge scale is 0.5 171 */ 172 if (priv->polarity > 1) 173 *val2 = 2; 174 else 175 *val2 = 1; 176 } 177 return IIO_VAL_FRACTIONAL_LOG2; 178 179 default: 180 return -EINVAL; 181 } 182 } 183 184 static const struct iio_info stm32_lptim_cnt_iio_info = { 185 .read_raw = stm32_lptim_read_raw, 186 .write_raw = stm32_lptim_write_raw, 187 }; 188 189 static const char *const stm32_lptim_quadrature_modes[] = { 190 "non-quadrature", 191 "quadrature", 192 }; 193 194 static int stm32_lptim_get_quadrature_mode(struct iio_dev *indio_dev, 195 const struct iio_chan_spec *chan) 196 { 197 struct stm32_lptim_cnt *priv = iio_priv(indio_dev); 198 199 return priv->quadrature_mode; 200 } 201 202 static int stm32_lptim_set_quadrature_mode(struct iio_dev *indio_dev, 203 const struct iio_chan_spec *chan, 204 unsigned int type) 205 { 206 struct stm32_lptim_cnt *priv = iio_priv(indio_dev); 207 208 if (stm32_lptim_is_enabled(priv)) 209 return -EBUSY; 210 211 priv->quadrature_mode = type; 212 213 return 0; 214 } 215 216 static const struct iio_enum stm32_lptim_quadrature_mode_en = { 217 .items = stm32_lptim_quadrature_modes, 218 .num_items = ARRAY_SIZE(stm32_lptim_quadrature_modes), 219 .get = stm32_lptim_get_quadrature_mode, 220 .set = stm32_lptim_set_quadrature_mode, 221 }; 222 223 static const char * const stm32_lptim_cnt_polarity[] = { 224 "rising-edge", "falling-edge", "both-edges", 225 }; 226 227 static int stm32_lptim_cnt_get_polarity(struct iio_dev *indio_dev, 228 const struct iio_chan_spec *chan) 229 { 230 struct stm32_lptim_cnt *priv = iio_priv(indio_dev); 231 232 return priv->polarity; 233 } 234 235 static int stm32_lptim_cnt_set_polarity(struct iio_dev *indio_dev, 236 const struct iio_chan_spec *chan, 237 unsigned int type) 238 { 239 struct stm32_lptim_cnt *priv = iio_priv(indio_dev); 240 241 if (stm32_lptim_is_enabled(priv)) 242 return -EBUSY; 243 244 priv->polarity = type; 245 246 return 0; 247 } 248 249 static const struct iio_enum stm32_lptim_cnt_polarity_en = { 250 .items = stm32_lptim_cnt_polarity, 251 .num_items = ARRAY_SIZE(stm32_lptim_cnt_polarity), 252 .get = stm32_lptim_cnt_get_polarity, 253 .set = stm32_lptim_cnt_set_polarity, 254 }; 255 256 static ssize_t stm32_lptim_cnt_get_ceiling(struct stm32_lptim_cnt *priv, 257 char *buf) 258 { 259 return snprintf(buf, PAGE_SIZE, "%u\n", priv->ceiling); 260 } 261 262 static ssize_t stm32_lptim_cnt_set_ceiling(struct stm32_lptim_cnt *priv, 263 const char *buf, size_t len) 264 { 265 int ret; 266 267 if (stm32_lptim_is_enabled(priv)) 268 return -EBUSY; 269 270 ret = kstrtouint(buf, 0, &priv->ceiling); 271 if (ret) 272 return ret; 273 274 if (priv->ceiling > STM32_LPTIM_MAX_ARR) 275 return -EINVAL; 276 277 return len; 278 } 279 280 static ssize_t stm32_lptim_cnt_get_preset_iio(struct iio_dev *indio_dev, 281 uintptr_t private, 282 const struct iio_chan_spec *chan, 283 char *buf) 284 { 285 struct stm32_lptim_cnt *priv = iio_priv(indio_dev); 286 287 return stm32_lptim_cnt_get_ceiling(priv, buf); 288 } 289 290 static ssize_t stm32_lptim_cnt_set_preset_iio(struct iio_dev *indio_dev, 291 uintptr_t private, 292 const struct iio_chan_spec *chan, 293 const char *buf, size_t len) 294 { 295 struct stm32_lptim_cnt *priv = iio_priv(indio_dev); 296 297 return stm32_lptim_cnt_set_ceiling(priv, buf, len); 298 } 299 300 /* LP timer with encoder */ 301 static const struct iio_chan_spec_ext_info stm32_lptim_enc_ext_info[] = { 302 { 303 .name = "preset", 304 .shared = IIO_SEPARATE, 305 .read = stm32_lptim_cnt_get_preset_iio, 306 .write = stm32_lptim_cnt_set_preset_iio, 307 }, 308 IIO_ENUM("polarity", IIO_SEPARATE, &stm32_lptim_cnt_polarity_en), 309 IIO_ENUM_AVAILABLE("polarity", &stm32_lptim_cnt_polarity_en), 310 IIO_ENUM("quadrature_mode", IIO_SEPARATE, 311 &stm32_lptim_quadrature_mode_en), 312 IIO_ENUM_AVAILABLE("quadrature_mode", &stm32_lptim_quadrature_mode_en), 313 {} 314 }; 315 316 static const struct iio_chan_spec stm32_lptim_enc_channels = { 317 .type = IIO_COUNT, 318 .channel = 0, 319 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | 320 BIT(IIO_CHAN_INFO_ENABLE) | 321 BIT(IIO_CHAN_INFO_SCALE), 322 .ext_info = stm32_lptim_enc_ext_info, 323 .indexed = 1, 324 }; 325 326 /* LP timer without encoder (counter only) */ 327 static const struct iio_chan_spec_ext_info stm32_lptim_cnt_ext_info[] = { 328 { 329 .name = "preset", 330 .shared = IIO_SEPARATE, 331 .read = stm32_lptim_cnt_get_preset_iio, 332 .write = stm32_lptim_cnt_set_preset_iio, 333 }, 334 IIO_ENUM("polarity", IIO_SEPARATE, &stm32_lptim_cnt_polarity_en), 335 IIO_ENUM_AVAILABLE("polarity", &stm32_lptim_cnt_polarity_en), 336 {} 337 }; 338 339 static const struct iio_chan_spec stm32_lptim_cnt_channels = { 340 .type = IIO_COUNT, 341 .channel = 0, 342 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | 343 BIT(IIO_CHAN_INFO_ENABLE) | 344 BIT(IIO_CHAN_INFO_SCALE), 345 .ext_info = stm32_lptim_cnt_ext_info, 346 .indexed = 1, 347 }; 348 349 /** 350 * enum stm32_lptim_cnt_function - enumerates LPTimer counter & encoder modes 351 * @STM32_LPTIM_COUNTER_INCREASE: up count on IN1 rising, falling or both edges 352 * @STM32_LPTIM_ENCODER_BOTH_EDGE: count on both edges (IN1 & IN2 quadrature) 353 */ 354 enum stm32_lptim_cnt_function { 355 STM32_LPTIM_COUNTER_INCREASE, 356 STM32_LPTIM_ENCODER_BOTH_EDGE, 357 }; 358 359 static enum counter_count_function stm32_lptim_cnt_functions[] = { 360 [STM32_LPTIM_COUNTER_INCREASE] = COUNTER_COUNT_FUNCTION_INCREASE, 361 [STM32_LPTIM_ENCODER_BOTH_EDGE] = COUNTER_COUNT_FUNCTION_QUADRATURE_X4, 362 }; 363 364 enum stm32_lptim_synapse_action { 365 STM32_LPTIM_SYNAPSE_ACTION_RISING_EDGE, 366 STM32_LPTIM_SYNAPSE_ACTION_FALLING_EDGE, 367 STM32_LPTIM_SYNAPSE_ACTION_BOTH_EDGES, 368 STM32_LPTIM_SYNAPSE_ACTION_NONE, 369 }; 370 371 static enum counter_synapse_action stm32_lptim_cnt_synapse_actions[] = { 372 /* Index must match with stm32_lptim_cnt_polarity[] (priv->polarity) */ 373 [STM32_LPTIM_SYNAPSE_ACTION_RISING_EDGE] = COUNTER_SYNAPSE_ACTION_RISING_EDGE, 374 [STM32_LPTIM_SYNAPSE_ACTION_FALLING_EDGE] = COUNTER_SYNAPSE_ACTION_FALLING_EDGE, 375 [STM32_LPTIM_SYNAPSE_ACTION_BOTH_EDGES] = COUNTER_SYNAPSE_ACTION_BOTH_EDGES, 376 [STM32_LPTIM_SYNAPSE_ACTION_NONE] = COUNTER_SYNAPSE_ACTION_NONE, 377 }; 378 379 static int stm32_lptim_cnt_read(struct counter_device *counter, 380 struct counter_count *count, unsigned long *val) 381 { 382 struct stm32_lptim_cnt *const priv = counter->priv; 383 u32 cnt; 384 int ret; 385 386 ret = regmap_read(priv->regmap, STM32_LPTIM_CNT, &cnt); 387 if (ret) 388 return ret; 389 390 *val = cnt; 391 392 return 0; 393 } 394 395 static int stm32_lptim_cnt_function_get(struct counter_device *counter, 396 struct counter_count *count, 397 size_t *function) 398 { 399 struct stm32_lptim_cnt *const priv = counter->priv; 400 401 if (!priv->quadrature_mode) { 402 *function = STM32_LPTIM_COUNTER_INCREASE; 403 return 0; 404 } 405 406 if (priv->polarity == STM32_LPTIM_SYNAPSE_ACTION_BOTH_EDGES) { 407 *function = STM32_LPTIM_ENCODER_BOTH_EDGE; 408 return 0; 409 } 410 411 return -EINVAL; 412 } 413 414 static int stm32_lptim_cnt_function_set(struct counter_device *counter, 415 struct counter_count *count, 416 size_t function) 417 { 418 struct stm32_lptim_cnt *const priv = counter->priv; 419 420 if (stm32_lptim_is_enabled(priv)) 421 return -EBUSY; 422 423 switch (function) { 424 case STM32_LPTIM_COUNTER_INCREASE: 425 priv->quadrature_mode = 0; 426 return 0; 427 case STM32_LPTIM_ENCODER_BOTH_EDGE: 428 priv->quadrature_mode = 1; 429 priv->polarity = STM32_LPTIM_SYNAPSE_ACTION_BOTH_EDGES; 430 return 0; 431 } 432 433 return -EINVAL; 434 } 435 436 static ssize_t stm32_lptim_cnt_enable_read(struct counter_device *counter, 437 struct counter_count *count, 438 void *private, char *buf) 439 { 440 struct stm32_lptim_cnt *const priv = counter->priv; 441 int ret; 442 443 ret = stm32_lptim_is_enabled(priv); 444 if (ret < 0) 445 return ret; 446 447 return scnprintf(buf, PAGE_SIZE, "%u\n", ret); 448 } 449 450 static ssize_t stm32_lptim_cnt_enable_write(struct counter_device *counter, 451 struct counter_count *count, 452 void *private, 453 const char *buf, size_t len) 454 { 455 struct stm32_lptim_cnt *const priv = counter->priv; 456 bool enable; 457 int ret; 458 459 ret = kstrtobool(buf, &enable); 460 if (ret) 461 return ret; 462 463 /* Check nobody uses the timer, or already disabled/enabled */ 464 ret = stm32_lptim_is_enabled(priv); 465 if ((ret < 0) || (!ret && !enable)) 466 return ret; 467 if (enable && ret) 468 return -EBUSY; 469 470 ret = stm32_lptim_setup(priv, enable); 471 if (ret) 472 return ret; 473 474 ret = stm32_lptim_set_enable_state(priv, enable); 475 if (ret) 476 return ret; 477 478 return len; 479 } 480 481 static ssize_t stm32_lptim_cnt_ceiling_read(struct counter_device *counter, 482 struct counter_count *count, 483 void *private, char *buf) 484 { 485 struct stm32_lptim_cnt *const priv = counter->priv; 486 487 return stm32_lptim_cnt_get_ceiling(priv, buf); 488 } 489 490 static ssize_t stm32_lptim_cnt_ceiling_write(struct counter_device *counter, 491 struct counter_count *count, 492 void *private, 493 const char *buf, size_t len) 494 { 495 struct stm32_lptim_cnt *const priv = counter->priv; 496 497 return stm32_lptim_cnt_set_ceiling(priv, buf, len); 498 } 499 500 static const struct counter_count_ext stm32_lptim_cnt_ext[] = { 501 { 502 .name = "enable", 503 .read = stm32_lptim_cnt_enable_read, 504 .write = stm32_lptim_cnt_enable_write 505 }, 506 { 507 .name = "ceiling", 508 .read = stm32_lptim_cnt_ceiling_read, 509 .write = stm32_lptim_cnt_ceiling_write 510 }, 511 }; 512 513 static int stm32_lptim_cnt_action_get(struct counter_device *counter, 514 struct counter_count *count, 515 struct counter_synapse *synapse, 516 size_t *action) 517 { 518 struct stm32_lptim_cnt *const priv = counter->priv; 519 size_t function; 520 int err; 521 522 err = stm32_lptim_cnt_function_get(counter, count, &function); 523 if (err) 524 return err; 525 526 switch (function) { 527 case STM32_LPTIM_COUNTER_INCREASE: 528 /* LP Timer acts as up-counter on input 1 */ 529 if (synapse->signal->id == count->synapses[0].signal->id) 530 *action = priv->polarity; 531 else 532 *action = STM32_LPTIM_SYNAPSE_ACTION_NONE; 533 return 0; 534 case STM32_LPTIM_ENCODER_BOTH_EDGE: 535 *action = priv->polarity; 536 return 0; 537 } 538 539 return -EINVAL; 540 } 541 542 static int stm32_lptim_cnt_action_set(struct counter_device *counter, 543 struct counter_count *count, 544 struct counter_synapse *synapse, 545 size_t action) 546 { 547 struct stm32_lptim_cnt *const priv = counter->priv; 548 size_t function; 549 int err; 550 551 if (stm32_lptim_is_enabled(priv)) 552 return -EBUSY; 553 554 err = stm32_lptim_cnt_function_get(counter, count, &function); 555 if (err) 556 return err; 557 558 /* only set polarity when in counter mode (on input 1) */ 559 if (function == STM32_LPTIM_COUNTER_INCREASE 560 && synapse->signal->id == count->synapses[0].signal->id) { 561 switch (action) { 562 case STM32_LPTIM_SYNAPSE_ACTION_RISING_EDGE: 563 case STM32_LPTIM_SYNAPSE_ACTION_FALLING_EDGE: 564 case STM32_LPTIM_SYNAPSE_ACTION_BOTH_EDGES: 565 priv->polarity = action; 566 return 0; 567 } 568 } 569 570 return -EINVAL; 571 } 572 573 static const struct counter_ops stm32_lptim_cnt_ops = { 574 .count_read = stm32_lptim_cnt_read, 575 .function_get = stm32_lptim_cnt_function_get, 576 .function_set = stm32_lptim_cnt_function_set, 577 .action_get = stm32_lptim_cnt_action_get, 578 .action_set = stm32_lptim_cnt_action_set, 579 }; 580 581 static struct counter_signal stm32_lptim_cnt_signals[] = { 582 { 583 .id = 0, 584 .name = "Channel 1 Quadrature A" 585 }, 586 { 587 .id = 1, 588 .name = "Channel 1 Quadrature B" 589 } 590 }; 591 592 static struct counter_synapse stm32_lptim_cnt_synapses[] = { 593 { 594 .actions_list = stm32_lptim_cnt_synapse_actions, 595 .num_actions = ARRAY_SIZE(stm32_lptim_cnt_synapse_actions), 596 .signal = &stm32_lptim_cnt_signals[0] 597 }, 598 { 599 .actions_list = stm32_lptim_cnt_synapse_actions, 600 .num_actions = ARRAY_SIZE(stm32_lptim_cnt_synapse_actions), 601 .signal = &stm32_lptim_cnt_signals[1] 602 } 603 }; 604 605 /* LP timer with encoder */ 606 static struct counter_count stm32_lptim_enc_counts = { 607 .id = 0, 608 .name = "LPTimer Count", 609 .functions_list = stm32_lptim_cnt_functions, 610 .num_functions = ARRAY_SIZE(stm32_lptim_cnt_functions), 611 .synapses = stm32_lptim_cnt_synapses, 612 .num_synapses = ARRAY_SIZE(stm32_lptim_cnt_synapses), 613 .ext = stm32_lptim_cnt_ext, 614 .num_ext = ARRAY_SIZE(stm32_lptim_cnt_ext) 615 }; 616 617 /* LP timer without encoder (counter only) */ 618 static struct counter_count stm32_lptim_in1_counts = { 619 .id = 0, 620 .name = "LPTimer Count", 621 .functions_list = stm32_lptim_cnt_functions, 622 .num_functions = 1, 623 .synapses = stm32_lptim_cnt_synapses, 624 .num_synapses = 1, 625 .ext = stm32_lptim_cnt_ext, 626 .num_ext = ARRAY_SIZE(stm32_lptim_cnt_ext) 627 }; 628 629 static int stm32_lptim_cnt_probe(struct platform_device *pdev) 630 { 631 struct stm32_lptimer *ddata = dev_get_drvdata(pdev->dev.parent); 632 struct stm32_lptim_cnt *priv; 633 struct iio_dev *indio_dev; 634 int ret; 635 636 if (IS_ERR_OR_NULL(ddata)) 637 return -EINVAL; 638 639 indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*priv)); 640 if (!indio_dev) 641 return -ENOMEM; 642 643 priv = iio_priv(indio_dev); 644 priv->dev = &pdev->dev; 645 priv->regmap = ddata->regmap; 646 priv->clk = ddata->clk; 647 priv->ceiling = STM32_LPTIM_MAX_ARR; 648 649 /* Initialize IIO device */ 650 indio_dev->name = dev_name(&pdev->dev); 651 indio_dev->dev.parent = &pdev->dev; 652 indio_dev->dev.of_node = pdev->dev.of_node; 653 indio_dev->info = &stm32_lptim_cnt_iio_info; 654 if (ddata->has_encoder) 655 indio_dev->channels = &stm32_lptim_enc_channels; 656 else 657 indio_dev->channels = &stm32_lptim_cnt_channels; 658 indio_dev->num_channels = 1; 659 660 /* Initialize Counter device */ 661 priv->counter.name = dev_name(&pdev->dev); 662 priv->counter.parent = &pdev->dev; 663 priv->counter.ops = &stm32_lptim_cnt_ops; 664 if (ddata->has_encoder) { 665 priv->counter.counts = &stm32_lptim_enc_counts; 666 priv->counter.num_signals = ARRAY_SIZE(stm32_lptim_cnt_signals); 667 } else { 668 priv->counter.counts = &stm32_lptim_in1_counts; 669 priv->counter.num_signals = 1; 670 } 671 priv->counter.num_counts = 1; 672 priv->counter.signals = stm32_lptim_cnt_signals; 673 priv->counter.priv = priv; 674 675 platform_set_drvdata(pdev, priv); 676 677 ret = devm_iio_device_register(&pdev->dev, indio_dev); 678 if (ret) 679 return ret; 680 681 return devm_counter_register(&pdev->dev, &priv->counter); 682 } 683 684 #ifdef CONFIG_PM_SLEEP 685 static int stm32_lptim_cnt_suspend(struct device *dev) 686 { 687 struct stm32_lptim_cnt *priv = dev_get_drvdata(dev); 688 int ret; 689 690 /* Only take care of enabled counter: don't disturb other MFD child */ 691 if (priv->enabled) { 692 ret = stm32_lptim_setup(priv, 0); 693 if (ret) 694 return ret; 695 696 ret = stm32_lptim_set_enable_state(priv, 0); 697 if (ret) 698 return ret; 699 700 /* Force enable state for later resume */ 701 priv->enabled = true; 702 } 703 704 return pinctrl_pm_select_sleep_state(dev); 705 } 706 707 static int stm32_lptim_cnt_resume(struct device *dev) 708 { 709 struct stm32_lptim_cnt *priv = dev_get_drvdata(dev); 710 int ret; 711 712 ret = pinctrl_pm_select_default_state(dev); 713 if (ret) 714 return ret; 715 716 if (priv->enabled) { 717 priv->enabled = false; 718 ret = stm32_lptim_setup(priv, 1); 719 if (ret) 720 return ret; 721 722 ret = stm32_lptim_set_enable_state(priv, 1); 723 if (ret) 724 return ret; 725 } 726 727 return 0; 728 } 729 #endif 730 731 static SIMPLE_DEV_PM_OPS(stm32_lptim_cnt_pm_ops, stm32_lptim_cnt_suspend, 732 stm32_lptim_cnt_resume); 733 734 static const struct of_device_id stm32_lptim_cnt_of_match[] = { 735 { .compatible = "st,stm32-lptimer-counter", }, 736 {}, 737 }; 738 MODULE_DEVICE_TABLE(of, stm32_lptim_cnt_of_match); 739 740 static struct platform_driver stm32_lptim_cnt_driver = { 741 .probe = stm32_lptim_cnt_probe, 742 .driver = { 743 .name = "stm32-lptimer-counter", 744 .of_match_table = stm32_lptim_cnt_of_match, 745 .pm = &stm32_lptim_cnt_pm_ops, 746 }, 747 }; 748 module_platform_driver(stm32_lptim_cnt_driver); 749 750 MODULE_AUTHOR("Fabrice Gasnier <fabrice.gasnier@st.com>"); 751 MODULE_ALIAS("platform:stm32-lptimer-counter"); 752 MODULE_DESCRIPTION("STMicroelectronics STM32 LPTIM counter driver"); 753 MODULE_LICENSE("GPL v2"); 754