1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Copyright (C) STMicroelectronics 2016 4 * 5 * Author: Benjamin Gaignard <benjamin.gaignard@st.com> 6 * 7 */ 8 9 #include <linux/iio/iio.h> 10 #include <linux/iio/sysfs.h> 11 #include <linux/iio/timer/stm32-timer-trigger.h> 12 #include <linux/iio/trigger.h> 13 #include <linux/mfd/stm32-timers.h> 14 #include <linux/module.h> 15 #include <linux/platform_device.h> 16 #include <linux/of_device.h> 17 18 #define MAX_TRIGGERS 7 19 #define MAX_VALIDS 5 20 21 /* List the triggers created by each timer */ 22 static const void *triggers_table[][MAX_TRIGGERS] = { 23 { TIM1_TRGO, TIM1_TRGO2, TIM1_CH1, TIM1_CH2, TIM1_CH3, TIM1_CH4,}, 24 { TIM2_TRGO, TIM2_CH1, TIM2_CH2, TIM2_CH3, TIM2_CH4,}, 25 { TIM3_TRGO, TIM3_CH1, TIM3_CH2, TIM3_CH3, TIM3_CH4,}, 26 { TIM4_TRGO, TIM4_CH1, TIM4_CH2, TIM4_CH3, TIM4_CH4,}, 27 { TIM5_TRGO, TIM5_CH1, TIM5_CH2, TIM5_CH3, TIM5_CH4,}, 28 { TIM6_TRGO,}, 29 { TIM7_TRGO,}, 30 { TIM8_TRGO, TIM8_TRGO2, TIM8_CH1, TIM8_CH2, TIM8_CH3, TIM8_CH4,}, 31 { TIM9_TRGO, TIM9_CH1, TIM9_CH2,}, 32 { TIM10_OC1,}, 33 { TIM11_OC1,}, 34 { TIM12_TRGO, TIM12_CH1, TIM12_CH2,}, 35 { TIM13_OC1,}, 36 { TIM14_OC1,}, 37 { TIM15_TRGO,}, 38 { TIM16_OC1,}, 39 { TIM17_OC1,}, 40 }; 41 42 /* List the triggers accepted by each timer */ 43 static const void *valids_table[][MAX_VALIDS] = { 44 { TIM5_TRGO, TIM2_TRGO, TIM3_TRGO, TIM4_TRGO,}, 45 { TIM1_TRGO, TIM8_TRGO, TIM3_TRGO, TIM4_TRGO,}, 46 { TIM1_TRGO, TIM2_TRGO, TIM5_TRGO, TIM4_TRGO,}, 47 { TIM1_TRGO, TIM2_TRGO, TIM3_TRGO, TIM8_TRGO,}, 48 { TIM2_TRGO, TIM3_TRGO, TIM4_TRGO, TIM8_TRGO,}, 49 { }, /* timer 6 */ 50 { }, /* timer 7 */ 51 { TIM1_TRGO, TIM2_TRGO, TIM4_TRGO, TIM5_TRGO,}, 52 { TIM2_TRGO, TIM3_TRGO, TIM10_OC1, TIM11_OC1,}, 53 { }, /* timer 10 */ 54 { }, /* timer 11 */ 55 { TIM4_TRGO, TIM5_TRGO, TIM13_OC1, TIM14_OC1,}, 56 }; 57 58 static const void *stm32h7_valids_table[][MAX_VALIDS] = { 59 { TIM15_TRGO, TIM2_TRGO, TIM3_TRGO, TIM4_TRGO,}, 60 { TIM1_TRGO, TIM8_TRGO, TIM3_TRGO, TIM4_TRGO,}, 61 { TIM1_TRGO, TIM2_TRGO, TIM15_TRGO, TIM4_TRGO,}, 62 { TIM1_TRGO, TIM2_TRGO, TIM3_TRGO, TIM8_TRGO,}, 63 { TIM1_TRGO, TIM8_TRGO, TIM3_TRGO, TIM4_TRGO,}, 64 { }, /* timer 6 */ 65 { }, /* timer 7 */ 66 { TIM1_TRGO, TIM2_TRGO, TIM4_TRGO, TIM5_TRGO,}, 67 { }, /* timer 9 */ 68 { }, /* timer 10 */ 69 { }, /* timer 11 */ 70 { TIM4_TRGO, TIM5_TRGO, TIM13_OC1, TIM14_OC1,}, 71 { }, /* timer 13 */ 72 { }, /* timer 14 */ 73 { TIM1_TRGO, TIM3_TRGO, TIM16_OC1, TIM17_OC1,}, 74 { }, /* timer 16 */ 75 { }, /* timer 17 */ 76 }; 77 78 struct stm32_timer_trigger_regs { 79 u32 cr1; 80 u32 cr2; 81 u32 psc; 82 u32 arr; 83 u32 cnt; 84 u32 smcr; 85 }; 86 87 struct stm32_timer_trigger { 88 struct device *dev; 89 struct regmap *regmap; 90 struct clk *clk; 91 bool enabled; 92 u32 max_arr; 93 const void *triggers; 94 const void *valids; 95 bool has_trgo2; 96 struct mutex lock; /* concurrent sysfs configuration */ 97 struct list_head tr_list; 98 struct stm32_timer_trigger_regs bak; 99 }; 100 101 struct stm32_timer_trigger_cfg { 102 const void *(*valids_table)[MAX_VALIDS]; 103 const unsigned int num_valids_table; 104 }; 105 106 static bool stm32_timer_is_trgo2_name(const char *name) 107 { 108 return !!strstr(name, "trgo2"); 109 } 110 111 static bool stm32_timer_is_trgo_name(const char *name) 112 { 113 return (!!strstr(name, "trgo") && !strstr(name, "trgo2")); 114 } 115 116 static int stm32_timer_start(struct stm32_timer_trigger *priv, 117 struct iio_trigger *trig, 118 unsigned int frequency) 119 { 120 unsigned long long prd, div; 121 int prescaler = 0; 122 u32 ccer; 123 124 /* Period and prescaler values depends of clock rate */ 125 div = (unsigned long long)clk_get_rate(priv->clk); 126 127 do_div(div, frequency); 128 129 prd = div; 130 131 /* 132 * Increase prescaler value until we get a result that fit 133 * with auto reload register maximum value. 134 */ 135 while (div > priv->max_arr) { 136 prescaler++; 137 div = prd; 138 do_div(div, (prescaler + 1)); 139 } 140 prd = div; 141 142 if (prescaler > MAX_TIM_PSC) { 143 dev_err(priv->dev, "prescaler exceeds the maximum value\n"); 144 return -EINVAL; 145 } 146 147 /* Check if nobody else use the timer */ 148 regmap_read(priv->regmap, TIM_CCER, &ccer); 149 if (ccer & TIM_CCER_CCXE) 150 return -EBUSY; 151 152 mutex_lock(&priv->lock); 153 if (!priv->enabled) { 154 priv->enabled = true; 155 clk_enable(priv->clk); 156 } 157 158 regmap_write(priv->regmap, TIM_PSC, prescaler); 159 regmap_write(priv->regmap, TIM_ARR, prd - 1); 160 regmap_update_bits(priv->regmap, TIM_CR1, TIM_CR1_ARPE, TIM_CR1_ARPE); 161 162 /* Force master mode to update mode */ 163 if (stm32_timer_is_trgo2_name(trig->name)) 164 regmap_update_bits(priv->regmap, TIM_CR2, TIM_CR2_MMS2, 165 0x2 << TIM_CR2_MMS2_SHIFT); 166 else 167 regmap_update_bits(priv->regmap, TIM_CR2, TIM_CR2_MMS, 168 0x2 << TIM_CR2_MMS_SHIFT); 169 170 /* Make sure that registers are updated */ 171 regmap_update_bits(priv->regmap, TIM_EGR, TIM_EGR_UG, TIM_EGR_UG); 172 173 /* Enable controller */ 174 regmap_update_bits(priv->regmap, TIM_CR1, TIM_CR1_CEN, TIM_CR1_CEN); 175 mutex_unlock(&priv->lock); 176 177 return 0; 178 } 179 180 static void stm32_timer_stop(struct stm32_timer_trigger *priv, 181 struct iio_trigger *trig) 182 { 183 u32 ccer; 184 185 regmap_read(priv->regmap, TIM_CCER, &ccer); 186 if (ccer & TIM_CCER_CCXE) 187 return; 188 189 mutex_lock(&priv->lock); 190 /* Stop timer */ 191 regmap_update_bits(priv->regmap, TIM_CR1, TIM_CR1_ARPE, 0); 192 regmap_update_bits(priv->regmap, TIM_CR1, TIM_CR1_CEN, 0); 193 regmap_write(priv->regmap, TIM_PSC, 0); 194 regmap_write(priv->regmap, TIM_ARR, 0); 195 196 /* Force disable master mode */ 197 if (stm32_timer_is_trgo2_name(trig->name)) 198 regmap_update_bits(priv->regmap, TIM_CR2, TIM_CR2_MMS2, 0); 199 else 200 regmap_update_bits(priv->regmap, TIM_CR2, TIM_CR2_MMS, 0); 201 202 /* Make sure that registers are updated */ 203 regmap_update_bits(priv->regmap, TIM_EGR, TIM_EGR_UG, TIM_EGR_UG); 204 205 if (priv->enabled) { 206 priv->enabled = false; 207 clk_disable(priv->clk); 208 } 209 mutex_unlock(&priv->lock); 210 } 211 212 static ssize_t stm32_tt_store_frequency(struct device *dev, 213 struct device_attribute *attr, 214 const char *buf, size_t len) 215 { 216 struct iio_trigger *trig = to_iio_trigger(dev); 217 struct stm32_timer_trigger *priv = iio_trigger_get_drvdata(trig); 218 unsigned int freq; 219 int ret; 220 221 ret = kstrtouint(buf, 10, &freq); 222 if (ret) 223 return ret; 224 225 if (freq == 0) { 226 stm32_timer_stop(priv, trig); 227 } else { 228 ret = stm32_timer_start(priv, trig, freq); 229 if (ret) 230 return ret; 231 } 232 233 return len; 234 } 235 236 static ssize_t stm32_tt_read_frequency(struct device *dev, 237 struct device_attribute *attr, char *buf) 238 { 239 struct iio_trigger *trig = to_iio_trigger(dev); 240 struct stm32_timer_trigger *priv = iio_trigger_get_drvdata(trig); 241 u32 psc, arr, cr1; 242 unsigned long long freq = 0; 243 244 regmap_read(priv->regmap, TIM_CR1, &cr1); 245 regmap_read(priv->regmap, TIM_PSC, &psc); 246 regmap_read(priv->regmap, TIM_ARR, &arr); 247 248 if (cr1 & TIM_CR1_CEN) { 249 freq = (unsigned long long)clk_get_rate(priv->clk); 250 do_div(freq, psc + 1); 251 do_div(freq, arr + 1); 252 } 253 254 return sprintf(buf, "%d\n", (unsigned int)freq); 255 } 256 257 static IIO_DEV_ATTR_SAMP_FREQ(0660, 258 stm32_tt_read_frequency, 259 stm32_tt_store_frequency); 260 261 #define MASTER_MODE_MAX 7 262 #define MASTER_MODE2_MAX 15 263 264 static char *master_mode_table[] = { 265 "reset", 266 "enable", 267 "update", 268 "compare_pulse", 269 "OC1REF", 270 "OC2REF", 271 "OC3REF", 272 "OC4REF", 273 /* Master mode selection 2 only */ 274 "OC5REF", 275 "OC6REF", 276 "compare_pulse_OC4REF", 277 "compare_pulse_OC6REF", 278 "compare_pulse_OC4REF_r_or_OC6REF_r", 279 "compare_pulse_OC4REF_r_or_OC6REF_f", 280 "compare_pulse_OC5REF_r_or_OC6REF_r", 281 "compare_pulse_OC5REF_r_or_OC6REF_f", 282 }; 283 284 static ssize_t stm32_tt_show_master_mode(struct device *dev, 285 struct device_attribute *attr, 286 char *buf) 287 { 288 struct stm32_timer_trigger *priv = dev_get_drvdata(dev); 289 struct iio_trigger *trig = to_iio_trigger(dev); 290 u32 cr2; 291 292 regmap_read(priv->regmap, TIM_CR2, &cr2); 293 294 if (stm32_timer_is_trgo2_name(trig->name)) 295 cr2 = (cr2 & TIM_CR2_MMS2) >> TIM_CR2_MMS2_SHIFT; 296 else 297 cr2 = (cr2 & TIM_CR2_MMS) >> TIM_CR2_MMS_SHIFT; 298 299 return sysfs_emit(buf, "%s\n", master_mode_table[cr2]); 300 } 301 302 static ssize_t stm32_tt_store_master_mode(struct device *dev, 303 struct device_attribute *attr, 304 const char *buf, size_t len) 305 { 306 struct stm32_timer_trigger *priv = dev_get_drvdata(dev); 307 struct iio_trigger *trig = to_iio_trigger(dev); 308 u32 mask, shift, master_mode_max; 309 int i; 310 311 if (stm32_timer_is_trgo2_name(trig->name)) { 312 mask = TIM_CR2_MMS2; 313 shift = TIM_CR2_MMS2_SHIFT; 314 master_mode_max = MASTER_MODE2_MAX; 315 } else { 316 mask = TIM_CR2_MMS; 317 shift = TIM_CR2_MMS_SHIFT; 318 master_mode_max = MASTER_MODE_MAX; 319 } 320 321 for (i = 0; i <= master_mode_max; i++) { 322 if (!strncmp(master_mode_table[i], buf, 323 strlen(master_mode_table[i]))) { 324 mutex_lock(&priv->lock); 325 if (!priv->enabled) { 326 /* Clock should be enabled first */ 327 priv->enabled = true; 328 clk_enable(priv->clk); 329 } 330 regmap_update_bits(priv->regmap, TIM_CR2, mask, 331 i << shift); 332 mutex_unlock(&priv->lock); 333 return len; 334 } 335 } 336 337 return -EINVAL; 338 } 339 340 static ssize_t stm32_tt_show_master_mode_avail(struct device *dev, 341 struct device_attribute *attr, 342 char *buf) 343 { 344 struct iio_trigger *trig = to_iio_trigger(dev); 345 unsigned int i, master_mode_max; 346 size_t len = 0; 347 348 if (stm32_timer_is_trgo2_name(trig->name)) 349 master_mode_max = MASTER_MODE2_MAX; 350 else 351 master_mode_max = MASTER_MODE_MAX; 352 353 for (i = 0; i <= master_mode_max; i++) 354 len += scnprintf(buf + len, PAGE_SIZE - len, 355 "%s ", master_mode_table[i]); 356 357 /* replace trailing space by newline */ 358 buf[len - 1] = '\n'; 359 360 return len; 361 } 362 363 static IIO_DEVICE_ATTR(master_mode_available, 0444, 364 stm32_tt_show_master_mode_avail, NULL, 0); 365 366 static IIO_DEVICE_ATTR(master_mode, 0660, 367 stm32_tt_show_master_mode, 368 stm32_tt_store_master_mode, 369 0); 370 371 static struct attribute *stm32_trigger_attrs[] = { 372 &iio_dev_attr_sampling_frequency.dev_attr.attr, 373 &iio_dev_attr_master_mode.dev_attr.attr, 374 &iio_dev_attr_master_mode_available.dev_attr.attr, 375 NULL, 376 }; 377 378 static const struct attribute_group stm32_trigger_attr_group = { 379 .attrs = stm32_trigger_attrs, 380 }; 381 382 static const struct attribute_group *stm32_trigger_attr_groups[] = { 383 &stm32_trigger_attr_group, 384 NULL, 385 }; 386 387 static const struct iio_trigger_ops timer_trigger_ops = { 388 }; 389 390 static void stm32_unregister_iio_triggers(struct stm32_timer_trigger *priv) 391 { 392 struct iio_trigger *tr; 393 394 list_for_each_entry(tr, &priv->tr_list, alloc_list) 395 iio_trigger_unregister(tr); 396 } 397 398 static int stm32_register_iio_triggers(struct stm32_timer_trigger *priv) 399 { 400 int ret; 401 const char * const *cur = priv->triggers; 402 403 INIT_LIST_HEAD(&priv->tr_list); 404 405 while (cur && *cur) { 406 struct iio_trigger *trig; 407 bool cur_is_trgo = stm32_timer_is_trgo_name(*cur); 408 bool cur_is_trgo2 = stm32_timer_is_trgo2_name(*cur); 409 410 if (cur_is_trgo2 && !priv->has_trgo2) { 411 cur++; 412 continue; 413 } 414 415 trig = devm_iio_trigger_alloc(priv->dev, "%s", *cur); 416 if (!trig) 417 return -ENOMEM; 418 419 trig->dev.parent = priv->dev->parent; 420 trig->ops = &timer_trigger_ops; 421 422 /* 423 * sampling frequency and master mode attributes 424 * should only be available on trgo/trgo2 triggers 425 */ 426 if (cur_is_trgo || cur_is_trgo2) 427 trig->dev.groups = stm32_trigger_attr_groups; 428 429 iio_trigger_set_drvdata(trig, priv); 430 431 ret = iio_trigger_register(trig); 432 if (ret) { 433 stm32_unregister_iio_triggers(priv); 434 return ret; 435 } 436 437 list_add_tail(&trig->alloc_list, &priv->tr_list); 438 cur++; 439 } 440 441 return 0; 442 } 443 444 static int stm32_counter_read_raw(struct iio_dev *indio_dev, 445 struct iio_chan_spec const *chan, 446 int *val, int *val2, long mask) 447 { 448 struct stm32_timer_trigger *priv = iio_priv(indio_dev); 449 u32 dat; 450 451 switch (mask) { 452 case IIO_CHAN_INFO_RAW: 453 regmap_read(priv->regmap, TIM_CNT, &dat); 454 *val = dat; 455 return IIO_VAL_INT; 456 457 case IIO_CHAN_INFO_ENABLE: 458 regmap_read(priv->regmap, TIM_CR1, &dat); 459 *val = (dat & TIM_CR1_CEN) ? 1 : 0; 460 return IIO_VAL_INT; 461 462 case IIO_CHAN_INFO_SCALE: 463 regmap_read(priv->regmap, TIM_SMCR, &dat); 464 dat &= TIM_SMCR_SMS; 465 466 *val = 1; 467 *val2 = 0; 468 469 /* in quadrature case scale = 0.25 */ 470 if (dat == 3) 471 *val2 = 2; 472 473 return IIO_VAL_FRACTIONAL_LOG2; 474 } 475 476 return -EINVAL; 477 } 478 479 static int stm32_counter_write_raw(struct iio_dev *indio_dev, 480 struct iio_chan_spec const *chan, 481 int val, int val2, long mask) 482 { 483 struct stm32_timer_trigger *priv = iio_priv(indio_dev); 484 485 switch (mask) { 486 case IIO_CHAN_INFO_RAW: 487 return regmap_write(priv->regmap, TIM_CNT, val); 488 489 case IIO_CHAN_INFO_SCALE: 490 /* fixed scale */ 491 return -EINVAL; 492 493 case IIO_CHAN_INFO_ENABLE: 494 mutex_lock(&priv->lock); 495 if (val) { 496 if (!priv->enabled) { 497 priv->enabled = true; 498 clk_enable(priv->clk); 499 } 500 regmap_update_bits(priv->regmap, TIM_CR1, TIM_CR1_CEN, 501 TIM_CR1_CEN); 502 } else { 503 regmap_update_bits(priv->regmap, TIM_CR1, TIM_CR1_CEN, 504 0); 505 if (priv->enabled) { 506 priv->enabled = false; 507 clk_disable(priv->clk); 508 } 509 } 510 mutex_unlock(&priv->lock); 511 return 0; 512 } 513 514 return -EINVAL; 515 } 516 517 static int stm32_counter_validate_trigger(struct iio_dev *indio_dev, 518 struct iio_trigger *trig) 519 { 520 struct stm32_timer_trigger *priv = iio_priv(indio_dev); 521 const char * const *cur = priv->valids; 522 unsigned int i = 0; 523 524 if (!is_stm32_timer_trigger(trig)) 525 return -EINVAL; 526 527 while (cur && *cur) { 528 if (!strncmp(trig->name, *cur, strlen(trig->name))) { 529 regmap_update_bits(priv->regmap, 530 TIM_SMCR, TIM_SMCR_TS, 531 i << TIM_SMCR_TS_SHIFT); 532 return 0; 533 } 534 cur++; 535 i++; 536 } 537 538 return -EINVAL; 539 } 540 541 static const struct iio_info stm32_trigger_info = { 542 .validate_trigger = stm32_counter_validate_trigger, 543 .read_raw = stm32_counter_read_raw, 544 .write_raw = stm32_counter_write_raw 545 }; 546 547 static const char *const stm32_trigger_modes[] = { 548 "trigger", 549 }; 550 551 static int stm32_set_trigger_mode(struct iio_dev *indio_dev, 552 const struct iio_chan_spec *chan, 553 unsigned int mode) 554 { 555 struct stm32_timer_trigger *priv = iio_priv(indio_dev); 556 557 regmap_update_bits(priv->regmap, TIM_SMCR, TIM_SMCR_SMS, TIM_SMCR_SMS); 558 559 return 0; 560 } 561 562 static int stm32_get_trigger_mode(struct iio_dev *indio_dev, 563 const struct iio_chan_spec *chan) 564 { 565 struct stm32_timer_trigger *priv = iio_priv(indio_dev); 566 u32 smcr; 567 568 regmap_read(priv->regmap, TIM_SMCR, &smcr); 569 570 return (smcr & TIM_SMCR_SMS) == TIM_SMCR_SMS ? 0 : -EINVAL; 571 } 572 573 static const struct iio_enum stm32_trigger_mode_enum = { 574 .items = stm32_trigger_modes, 575 .num_items = ARRAY_SIZE(stm32_trigger_modes), 576 .set = stm32_set_trigger_mode, 577 .get = stm32_get_trigger_mode 578 }; 579 580 static const char *const stm32_enable_modes[] = { 581 "always", 582 "gated", 583 "triggered", 584 }; 585 586 static int stm32_enable_mode2sms(int mode) 587 { 588 switch (mode) { 589 case 0: 590 return 0; 591 case 1: 592 return 5; 593 case 2: 594 return 6; 595 } 596 597 return -EINVAL; 598 } 599 600 static int stm32_set_enable_mode(struct iio_dev *indio_dev, 601 const struct iio_chan_spec *chan, 602 unsigned int mode) 603 { 604 struct stm32_timer_trigger *priv = iio_priv(indio_dev); 605 int sms = stm32_enable_mode2sms(mode); 606 607 if (sms < 0) 608 return sms; 609 /* 610 * Triggered mode sets CEN bit automatically by hardware. So, first 611 * enable counter clock, so it can use it. Keeps it in sync with CEN. 612 */ 613 mutex_lock(&priv->lock); 614 if (sms == 6 && !priv->enabled) { 615 clk_enable(priv->clk); 616 priv->enabled = true; 617 } 618 mutex_unlock(&priv->lock); 619 620 regmap_update_bits(priv->regmap, TIM_SMCR, TIM_SMCR_SMS, sms); 621 622 return 0; 623 } 624 625 static int stm32_sms2enable_mode(int mode) 626 { 627 switch (mode) { 628 case 0: 629 return 0; 630 case 5: 631 return 1; 632 case 6: 633 return 2; 634 } 635 636 return -EINVAL; 637 } 638 639 static int stm32_get_enable_mode(struct iio_dev *indio_dev, 640 const struct iio_chan_spec *chan) 641 { 642 struct stm32_timer_trigger *priv = iio_priv(indio_dev); 643 u32 smcr; 644 645 regmap_read(priv->regmap, TIM_SMCR, &smcr); 646 smcr &= TIM_SMCR_SMS; 647 648 return stm32_sms2enable_mode(smcr); 649 } 650 651 static const struct iio_enum stm32_enable_mode_enum = { 652 .items = stm32_enable_modes, 653 .num_items = ARRAY_SIZE(stm32_enable_modes), 654 .set = stm32_set_enable_mode, 655 .get = stm32_get_enable_mode 656 }; 657 658 static ssize_t stm32_count_get_preset(struct iio_dev *indio_dev, 659 uintptr_t private, 660 const struct iio_chan_spec *chan, 661 char *buf) 662 { 663 struct stm32_timer_trigger *priv = iio_priv(indio_dev); 664 u32 arr; 665 666 regmap_read(priv->regmap, TIM_ARR, &arr); 667 668 return snprintf(buf, PAGE_SIZE, "%u\n", arr); 669 } 670 671 static ssize_t stm32_count_set_preset(struct iio_dev *indio_dev, 672 uintptr_t private, 673 const struct iio_chan_spec *chan, 674 const char *buf, size_t len) 675 { 676 struct stm32_timer_trigger *priv = iio_priv(indio_dev); 677 unsigned int preset; 678 int ret; 679 680 ret = kstrtouint(buf, 0, &preset); 681 if (ret) 682 return ret; 683 684 /* TIMx_ARR register shouldn't be buffered (ARPE=0) */ 685 regmap_update_bits(priv->regmap, TIM_CR1, TIM_CR1_ARPE, 0); 686 regmap_write(priv->regmap, TIM_ARR, preset); 687 688 return len; 689 } 690 691 static const struct iio_chan_spec_ext_info stm32_trigger_count_info[] = { 692 { 693 .name = "preset", 694 .shared = IIO_SEPARATE, 695 .read = stm32_count_get_preset, 696 .write = stm32_count_set_preset 697 }, 698 IIO_ENUM("enable_mode", IIO_SEPARATE, &stm32_enable_mode_enum), 699 IIO_ENUM_AVAILABLE("enable_mode", IIO_SHARED_BY_TYPE, &stm32_enable_mode_enum), 700 IIO_ENUM("trigger_mode", IIO_SEPARATE, &stm32_trigger_mode_enum), 701 IIO_ENUM_AVAILABLE("trigger_mode", IIO_SHARED_BY_TYPE, &stm32_trigger_mode_enum), 702 {} 703 }; 704 705 static const struct iio_chan_spec stm32_trigger_channel = { 706 .type = IIO_COUNT, 707 .channel = 0, 708 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | 709 BIT(IIO_CHAN_INFO_ENABLE) | 710 BIT(IIO_CHAN_INFO_SCALE), 711 .ext_info = stm32_trigger_count_info, 712 .indexed = 1 713 }; 714 715 static struct stm32_timer_trigger *stm32_setup_counter_device(struct device *dev) 716 { 717 struct iio_dev *indio_dev; 718 int ret; 719 720 indio_dev = devm_iio_device_alloc(dev, 721 sizeof(struct stm32_timer_trigger)); 722 if (!indio_dev) 723 return NULL; 724 725 indio_dev->name = dev_name(dev); 726 indio_dev->info = &stm32_trigger_info; 727 indio_dev->modes = INDIO_HARDWARE_TRIGGERED; 728 indio_dev->num_channels = 1; 729 indio_dev->channels = &stm32_trigger_channel; 730 731 ret = devm_iio_device_register(dev, indio_dev); 732 if (ret) 733 return NULL; 734 735 return iio_priv(indio_dev); 736 } 737 738 /** 739 * is_stm32_timer_trigger 740 * @trig: trigger to be checked 741 * 742 * return true if the trigger is a valid stm32 iio timer trigger 743 * either return false 744 */ 745 bool is_stm32_timer_trigger(struct iio_trigger *trig) 746 { 747 return (trig->ops == &timer_trigger_ops); 748 } 749 EXPORT_SYMBOL(is_stm32_timer_trigger); 750 751 static void stm32_timer_detect_trgo2(struct stm32_timer_trigger *priv) 752 { 753 u32 val; 754 755 /* 756 * Master mode selection 2 bits can only be written and read back when 757 * timer supports it. 758 */ 759 regmap_update_bits(priv->regmap, TIM_CR2, TIM_CR2_MMS2, TIM_CR2_MMS2); 760 regmap_read(priv->regmap, TIM_CR2, &val); 761 regmap_update_bits(priv->regmap, TIM_CR2, TIM_CR2_MMS2, 0); 762 priv->has_trgo2 = !!val; 763 } 764 765 static int stm32_timer_trigger_probe(struct platform_device *pdev) 766 { 767 struct device *dev = &pdev->dev; 768 struct stm32_timer_trigger *priv; 769 struct stm32_timers *ddata = dev_get_drvdata(pdev->dev.parent); 770 const struct stm32_timer_trigger_cfg *cfg; 771 unsigned int index; 772 int ret; 773 774 if (of_property_read_u32(dev->of_node, "reg", &index)) 775 return -EINVAL; 776 777 cfg = (const struct stm32_timer_trigger_cfg *) 778 of_match_device(dev->driver->of_match_table, dev)->data; 779 780 if (index >= ARRAY_SIZE(triggers_table) || 781 index >= cfg->num_valids_table) 782 return -EINVAL; 783 784 /* Create an IIO device only if we have triggers to be validated */ 785 if (*cfg->valids_table[index]) 786 priv = stm32_setup_counter_device(dev); 787 else 788 priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); 789 790 if (!priv) 791 return -ENOMEM; 792 793 priv->dev = dev; 794 priv->regmap = ddata->regmap; 795 priv->clk = ddata->clk; 796 priv->max_arr = ddata->max_arr; 797 priv->triggers = triggers_table[index]; 798 priv->valids = cfg->valids_table[index]; 799 stm32_timer_detect_trgo2(priv); 800 mutex_init(&priv->lock); 801 802 ret = stm32_register_iio_triggers(priv); 803 if (ret) 804 return ret; 805 806 platform_set_drvdata(pdev, priv); 807 808 return 0; 809 } 810 811 static int stm32_timer_trigger_remove(struct platform_device *pdev) 812 { 813 struct stm32_timer_trigger *priv = platform_get_drvdata(pdev); 814 u32 val; 815 816 /* Unregister triggers before everything can be safely turned off */ 817 stm32_unregister_iio_triggers(priv); 818 819 /* Check if nobody else use the timer, then disable it */ 820 regmap_read(priv->regmap, TIM_CCER, &val); 821 if (!(val & TIM_CCER_CCXE)) 822 regmap_update_bits(priv->regmap, TIM_CR1, TIM_CR1_CEN, 0); 823 824 if (priv->enabled) 825 clk_disable(priv->clk); 826 827 return 0; 828 } 829 830 static int __maybe_unused stm32_timer_trigger_suspend(struct device *dev) 831 { 832 struct stm32_timer_trigger *priv = dev_get_drvdata(dev); 833 834 /* Only take care of enabled timer: don't disturb other MFD child */ 835 if (priv->enabled) { 836 /* Backup registers that may get lost in low power mode */ 837 regmap_read(priv->regmap, TIM_CR1, &priv->bak.cr1); 838 regmap_read(priv->regmap, TIM_CR2, &priv->bak.cr2); 839 regmap_read(priv->regmap, TIM_PSC, &priv->bak.psc); 840 regmap_read(priv->regmap, TIM_ARR, &priv->bak.arr); 841 regmap_read(priv->regmap, TIM_CNT, &priv->bak.cnt); 842 regmap_read(priv->regmap, TIM_SMCR, &priv->bak.smcr); 843 844 /* Disable the timer */ 845 regmap_update_bits(priv->regmap, TIM_CR1, TIM_CR1_CEN, 0); 846 clk_disable(priv->clk); 847 } 848 849 return 0; 850 } 851 852 static int __maybe_unused stm32_timer_trigger_resume(struct device *dev) 853 { 854 struct stm32_timer_trigger *priv = dev_get_drvdata(dev); 855 int ret; 856 857 if (priv->enabled) { 858 ret = clk_enable(priv->clk); 859 if (ret) 860 return ret; 861 862 /* restore master/slave modes */ 863 regmap_write(priv->regmap, TIM_SMCR, priv->bak.smcr); 864 regmap_write(priv->regmap, TIM_CR2, priv->bak.cr2); 865 866 /* restore sampling_frequency (trgo / trgo2 triggers) */ 867 regmap_write(priv->regmap, TIM_PSC, priv->bak.psc); 868 regmap_write(priv->regmap, TIM_ARR, priv->bak.arr); 869 regmap_write(priv->regmap, TIM_CNT, priv->bak.cnt); 870 871 /* Also re-enables the timer */ 872 regmap_write(priv->regmap, TIM_CR1, priv->bak.cr1); 873 } 874 875 return 0; 876 } 877 878 static SIMPLE_DEV_PM_OPS(stm32_timer_trigger_pm_ops, 879 stm32_timer_trigger_suspend, 880 stm32_timer_trigger_resume); 881 882 static const struct stm32_timer_trigger_cfg stm32_timer_trg_cfg = { 883 .valids_table = valids_table, 884 .num_valids_table = ARRAY_SIZE(valids_table), 885 }; 886 887 static const struct stm32_timer_trigger_cfg stm32h7_timer_trg_cfg = { 888 .valids_table = stm32h7_valids_table, 889 .num_valids_table = ARRAY_SIZE(stm32h7_valids_table), 890 }; 891 892 static const struct of_device_id stm32_trig_of_match[] = { 893 { 894 .compatible = "st,stm32-timer-trigger", 895 .data = (void *)&stm32_timer_trg_cfg, 896 }, { 897 .compatible = "st,stm32h7-timer-trigger", 898 .data = (void *)&stm32h7_timer_trg_cfg, 899 }, 900 { /* end node */ }, 901 }; 902 MODULE_DEVICE_TABLE(of, stm32_trig_of_match); 903 904 static struct platform_driver stm32_timer_trigger_driver = { 905 .probe = stm32_timer_trigger_probe, 906 .remove = stm32_timer_trigger_remove, 907 .driver = { 908 .name = "stm32-timer-trigger", 909 .of_match_table = stm32_trig_of_match, 910 .pm = &stm32_timer_trigger_pm_ops, 911 }, 912 }; 913 module_platform_driver(stm32_timer_trigger_driver); 914 915 MODULE_ALIAS("platform:stm32-timer-trigger"); 916 MODULE_DESCRIPTION("STMicroelectronics STM32 Timer Trigger driver"); 917 MODULE_LICENSE("GPL v2"); 918