drivers/ptp/ptp_chardev.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * PTP 1588 clock support - character device implementation.
   4  *
   5  * Copyright (C) 2010 OMICRON electronics GmbH
   6  */
   7 #include <linux/module.h>
   8 #include <linux/posix-clock.h>
   9 #include <linux/poll.h>
  10 #include <linux/sched.h>
  11 #include <linux/slab.h>
  12 #include <linux/timekeeping.h>
  13 #include <linux/debugfs.h>
  14
  15 #include <linux/nospec.h>
  16
  17 #include "ptp_private.h"
  18
  19 static int ptp_disable_pinfunc(struct ptp_clock_info *ops,
  20                                enum ptp_pin_function func, unsigned int chan)
  21 {
  22         struct ptp_clock_request rq;
  23         int err = 0;
  24
  25         memset(&rq, 0, sizeof(rq));
  26
  27         switch (func) {
  28         case PTP_PF_NONE:
  29                 break;
  30         case PTP_PF_EXTTS:
  31                 rq.type = PTP_CLK_REQ_EXTTS;
  32                 rq.extts.index = chan;
  33                 err = ops->enable(ops, &rq, 0);
  34                 break;
  35         case PTP_PF_PEROUT:
  36                 rq.type = PTP_CLK_REQ_PEROUT;
  37                 rq.perout.index = chan;
  38                 err = ops->enable(ops, &rq, 0);
  39                 break;
  40         case PTP_PF_PHYSYNC:
  41                 break;
  42         default:
  43                 return -EINVAL;
  44         }
  45
  46         return err;
  47 }
  48
  49 int ptp_set_pinfunc(struct ptp_clock *ptp, unsigned int pin,
  50                     enum ptp_pin_function func, unsigned int chan)
  51 {
  52         struct ptp_clock_info *info = ptp->info;
  53         struct ptp_pin_desc *pin1 = NULL, *pin2 = &info->pin_config[pin];
  54         unsigned int i;
  55
  56         /* Check to see if any other pin previously had this function. */
  57         for (i = 0; i < info->n_pins; i++) {
  58                 if (info->pin_config[i].func == func &&
  59                     info->pin_config[i].chan == chan) {
  60                         pin1 = &info->pin_config[i];
  61                         break;
  62                 }
  63         }
  64         if (pin1 && i == pin)
  65                 return 0;
  66
  67         /* Check the desired function and channel. */
  68         switch (func) {
  69         case PTP_PF_NONE:
  70                 break;
  71         case PTP_PF_EXTTS:
  72                 if (chan >= info->n_ext_ts)
  73                         return -EINVAL;
  74                 break;
  75         case PTP_PF_PEROUT:
  76                 if (chan >= info->n_per_out)
  77                         return -EINVAL;
  78                 break;
  79         case PTP_PF_PHYSYNC:
  80                 if (chan != 0)
  81                         return -EINVAL;
  82                 break;
  83         default:
  84                 return -EINVAL;
  85         }
  86
  87         if (info->verify(info, pin, func, chan)) {
  88                 pr_err("driver cannot use function %u on pin %u\n", func, chan);
  89                 return -EOPNOTSUPP;
  90         }
  91
  92         /* Disable whatever function was previously assigned. */
  93         if (pin1) {
  94                 ptp_disable_pinfunc(info, func, chan);
  95                 pin1->func = PTP_PF_NONE;
  96                 pin1->chan = 0;
  97         }
  98         ptp_disable_pinfunc(info, pin2->func, pin2->chan);
  99         pin2->func = func;
 100         pin2->chan = chan;
 101
 102         return 0;
 103 }
 104
 105 int ptp_open(struct posix_clock_context *pccontext, fmode_t fmode)
 106 {
 107         struct ptp_clock *ptp =
 108                 container_of(pccontext->clk, struct ptp_clock, clock);
 109         struct timestamp_event_queue *queue;
 110         char debugfsname[32];
 111         unsigned long flags;
 112
 113         queue = kzalloc(sizeof(*queue), GFP_KERNEL);
 114         if (!queue)
 115                 return -EINVAL;
 116         queue->mask = bitmap_alloc(PTP_MAX_CHANNELS, GFP_KERNEL);
 117         if (!queue->mask) {
 118                 kfree(queue);
 119                 return -EINVAL;
 120         }
 121         bitmap_set(queue->mask, 0, PTP_MAX_CHANNELS);
 122         spin_lock_init(&queue->lock);
 123         spin_lock_irqsave(&ptp->tsevqs_lock, flags);
 124         list_add_tail(&queue->qlist, &ptp->tsevqs);
 125         spin_unlock_irqrestore(&ptp->tsevqs_lock, flags);
 126         pccontext->private_clkdata = queue;
 127
 128         /* Debugfs contents */
 129         sprintf(debugfsname, "0x%p", queue);
 130         queue->debugfs_instance =
 131                 debugfs_create_dir(debugfsname, ptp->debugfs_root);
 132         queue->dfs_bitmap.array = (u32 *)queue->mask;
 133         queue->dfs_bitmap.n_elements =
 134                 DIV_ROUND_UP(PTP_MAX_CHANNELS, BITS_PER_BYTE * sizeof(u32));
 135         debugfs_create_u32_array("mask", 0444, queue->debugfs_instance,
 136                                  &queue->dfs_bitmap);
 137
 138         return 0;
 139 }
 140
 141 int ptp_release(struct posix_clock_context *pccontext)
 142 {
 143         struct timestamp_event_queue *queue = pccontext->private_clkdata;
 144         unsigned long flags;
 145         struct ptp_clock *ptp =
 146                 container_of(pccontext->clk, struct ptp_clock, clock);
 147
 148         debugfs_remove(queue->debugfs_instance);
 149         pccontext->private_clkdata = NULL;
 150         spin_lock_irqsave(&ptp->tsevqs_lock, flags);
 151         list_del(&queue->qlist);
 152         spin_unlock_irqrestore(&ptp->tsevqs_lock, flags);
 153         bitmap_free(queue->mask);
 154         kfree(queue);
 155         return 0;
 156 }
 157
 158 long ptp_ioctl(struct posix_clock_context *pccontext, unsigned int cmd,
 159                unsigned long arg)
 160 {
 161         struct ptp_clock *ptp =
 162                 container_of(pccontext->clk, struct ptp_clock, clock);
 163         struct ptp_sys_offset_extended *extoff = NULL;
 164         struct ptp_sys_offset_precise precise_offset;
 165         struct system_device_crosststamp xtstamp;
 166         struct ptp_clock_info *ops = ptp->info;
 167         struct ptp_sys_offset *sysoff = NULL;
 168         struct timestamp_event_queue *tsevq;
 169         struct ptp_system_timestamp sts;
 170         struct ptp_clock_request req;
 171         struct ptp_clock_caps caps;
 172         struct ptp_clock_time *pct;
 173         unsigned int i, pin_index;
 174         struct ptp_pin_desc pd;
 175         struct timespec64 ts;
 176         int enable, err = 0;
 177
 178         tsevq = pccontext->private_clkdata;
 179
 180         switch (cmd) {
 181
 182         case PTP_CLOCK_GETCAPS:
 183         case PTP_CLOCK_GETCAPS2:
 184                 memset(&caps, 0, sizeof(caps));
 185
 186                 caps.max_adj = ptp->info->max_adj;
 187                 caps.n_alarm = ptp->info->n_alarm;
 188                 caps.n_ext_ts = ptp->info->n_ext_ts;
 189                 caps.n_per_out = ptp->info->n_per_out;
 190                 caps.pps = ptp->info->pps;
 191                 caps.n_pins = ptp->info->n_pins;
 192                 caps.cross_timestamping = ptp->info->getcrosststamp != NULL;
 193                 caps.adjust_phase = ptp->info->adjphase != NULL &&
 194                                     ptp->info->getmaxphase != NULL;
 195                 if (caps.adjust_phase)
 196                         caps.max_phase_adj = ptp->info->getmaxphase(ptp->info);
 197                 if (copy_to_user((void __user *)arg, &caps, sizeof(caps)))
 198                         err = -EFAULT;
 199                 break;
 200
 201         case PTP_EXTTS_REQUEST:
 202         case PTP_EXTTS_REQUEST2:
 203                 memset(&req, 0, sizeof(req));
 204
 205                 if (copy_from_user(&req.extts, (void __user *)arg,
 206                                    sizeof(req.extts))) {
 207                         err = -EFAULT;
 208                         break;
 209                 }
 210                 if (cmd == PTP_EXTTS_REQUEST2) {
 211                         /* Tell the drivers to check the flags carefully. */
 212                         req.extts.flags |= PTP_STRICT_FLAGS;
 213                         /* Make sure no reserved bit is set. */
 214                         if ((req.extts.flags & ~PTP_EXTTS_VALID_FLAGS) ||
 215                             req.extts.rsv[0] || req.extts.rsv[1]) {
 216                                 err = -EINVAL;
 217                                 break;
 218                         }
 219                         /* Ensure one of the rising/falling edge bits is set. */
 220                         if ((req.extts.flags & PTP_ENABLE_FEATURE) &&
 221                             (req.extts.flags & PTP_EXTTS_EDGES) == 0) {
 222                                 err = -EINVAL;
 223                                 break;
 224                         }
 225                 } else if (cmd == PTP_EXTTS_REQUEST) {
 226                         req.extts.flags &= PTP_EXTTS_V1_VALID_FLAGS;
 227                         req.extts.rsv[0] = 0;
 228                         req.extts.rsv[1] = 0;
 229                 }
 230                 if (req.extts.index >= ops->n_ext_ts) {
 231                         err = -EINVAL;
 232                         break;
 233                 }
 234                 req.type = PTP_CLK_REQ_EXTTS;
 235                 enable = req.extts.flags & PTP_ENABLE_FEATURE ? 1 : 0;
 236                 if (mutex_lock_interruptible(&ptp->pincfg_mux))
 237                         return -ERESTARTSYS;
 238                 err = ops->enable(ops, &req, enable);
 239                 mutex_unlock(&ptp->pincfg_mux);
 240                 break;
 241
 242         case PTP_PEROUT_REQUEST:
 243         case PTP_PEROUT_REQUEST2:
 244                 memset(&req, 0, sizeof(req));
 245
 246                 if (copy_from_user(&req.perout, (void __user *)arg,
 247                                    sizeof(req.perout))) {
 248                         err = -EFAULT;
 249                         break;
 250                 }
 251                 if (cmd == PTP_PEROUT_REQUEST2) {
 252                         struct ptp_perout_request *perout = &req.perout;
 253
 254                         if (perout->flags & ~PTP_PEROUT_VALID_FLAGS) {
 255                                 err = -EINVAL;
 256                                 break;
 257                         }
 258                         /*
 259                          * The "on" field has undefined meaning if
 260                          * PTP_PEROUT_DUTY_CYCLE isn't set, we must still treat
 261                          * it as reserved, which must be set to zero.
 262                          */
 263                         if (!(perout->flags & PTP_PEROUT_DUTY_CYCLE) &&
 264                             (perout->rsv[0] || perout->rsv[1] ||
 265                              perout->rsv[2] || perout->rsv[3])) {
 266                                 err = -EINVAL;
 267                                 break;
 268                         }
 269                         if (perout->flags & PTP_PEROUT_DUTY_CYCLE) {
 270                                 /* The duty cycle must be subunitary. */
 271                                 if (perout->on.sec > perout->period.sec ||
 272                                     (perout->on.sec == perout->period.sec &&
 273                                      perout->on.nsec > perout->period.nsec)) {
 274                                         err = -ERANGE;
 275                                         break;
 276                                 }
 277                         }
 278                         if (perout->flags & PTP_PEROUT_PHASE) {
 279                                 /*
 280                                  * The phase should be specified modulo the
 281                                  * period, therefore anything equal or larger
 282                                  * than 1 period is invalid.
 283                                  */
 284                                 if (perout->phase.sec > perout->period.sec ||
 285                                     (perout->phase.sec == perout->period.sec &&
 286                                      perout->phase.nsec >= perout->period.nsec)) {
 287                                         err = -ERANGE;
 288                                         break;
 289                                 }
 290                         }
 291                 } else if (cmd == PTP_PEROUT_REQUEST) {
 292                         req.perout.flags &= PTP_PEROUT_V1_VALID_FLAGS;
 293                         req.perout.rsv[0] = 0;
 294                         req.perout.rsv[1] = 0;
 295                         req.perout.rsv[2] = 0;
 296                         req.perout.rsv[3] = 0;
 297                 }
 298                 if (req.perout.index >= ops->n_per_out) {
 299                         err = -EINVAL;
 300                         break;
 301                 }
 302                 req.type = PTP_CLK_REQ_PEROUT;
 303                 enable = req.perout.period.sec || req.perout.period.nsec;
 304                 if (mutex_lock_interruptible(&ptp->pincfg_mux))
 305                         return -ERESTARTSYS;
 306                 err = ops->enable(ops, &req, enable);
 307                 mutex_unlock(&ptp->pincfg_mux);
 308                 break;
 309
 310         case PTP_ENABLE_PPS:
 311         case PTP_ENABLE_PPS2:
 312                 memset(&req, 0, sizeof(req));
 313
 314                 if (!capable(CAP_SYS_TIME))
 315                         return -EPERM;
 316                 req.type = PTP_CLK_REQ_PPS;
 317                 enable = arg ? 1 : 0;
 318                 if (mutex_lock_interruptible(&ptp->pincfg_mux))
 319                         return -ERESTARTSYS;
 320                 err = ops->enable(ops, &req, enable);
 321                 mutex_unlock(&ptp->pincfg_mux);
 322                 break;
 323
 324         case PTP_SYS_OFFSET_PRECISE:
 325         case PTP_SYS_OFFSET_PRECISE2:
 326                 if (!ptp->info->getcrosststamp) {
 327                         err = -EOPNOTSUPP;
 328                         break;
 329                 }
 330                 err = ptp->info->getcrosststamp(ptp->info, &xtstamp);
 331                 if (err)
 332                         break;
 333
 334                 memset(&precise_offset, 0, sizeof(precise_offset));
 335                 ts = ktime_to_timespec64(xtstamp.device);
 336                 precise_offset.device.sec = ts.tv_sec;
 337                 precise_offset.device.nsec = ts.tv_nsec;
 338                 ts = ktime_to_timespec64(xtstamp.sys_realtime);
 339                 precise_offset.sys_realtime.sec = ts.tv_sec;
 340                 precise_offset.sys_realtime.nsec = ts.tv_nsec;
 341                 ts = ktime_to_timespec64(xtstamp.sys_monoraw);
 342                 precise_offset.sys_monoraw.sec = ts.tv_sec;
 343                 precise_offset.sys_monoraw.nsec = ts.tv_nsec;
 344                 if (copy_to_user((void __user *)arg, &precise_offset,
 345                                  sizeof(precise_offset)))
 346                         err = -EFAULT;
 347                 break;
 348
 349         case PTP_SYS_OFFSET_EXTENDED:
 350         case PTP_SYS_OFFSET_EXTENDED2:
 351                 if (!ptp->info->gettimex64) {
 352                         err = -EOPNOTSUPP;
 353                         break;
 354                 }
 355                 extoff = memdup_user((void __user *)arg, sizeof(*extoff));
 356                 if (IS_ERR(extoff)) {
 357                         err = PTR_ERR(extoff);
 358                         extoff = NULL;
 359                         break;
 360                 }
 361                 if (extoff->n_samples > PTP_MAX_SAMPLES
 362                     || extoff->rsv[0] || extoff->rsv[1] || extoff->rsv[2]) {
 363                         err = -EINVAL;
 364                         break;
 365                 }
 366                 for (i = 0; i < extoff->n_samples; i++) {
 367                         err = ptp->info->gettimex64(ptp->info, &ts, &sts);
 368                         if (err)
 369                                 goto out;
 370                         extoff->ts[i][0].sec = sts.pre_ts.tv_sec;
 371                         extoff->ts[i][0].nsec = sts.pre_ts.tv_nsec;
 372                         extoff->ts[i][1].sec = ts.tv_sec;
 373                         extoff->ts[i][1].nsec = ts.tv_nsec;
 374                         extoff->ts[i][2].sec = sts.post_ts.tv_sec;
 375                         extoff->ts[i][2].nsec = sts.post_ts.tv_nsec;
 376                 }
 377                 if (copy_to_user((void __user *)arg, extoff, sizeof(*extoff)))
 378                         err = -EFAULT;
 379                 break;
 380
 381         case PTP_SYS_OFFSET:
 382         case PTP_SYS_OFFSET2:
 383                 sysoff = memdup_user((void __user *)arg, sizeof(*sysoff));
 384                 if (IS_ERR(sysoff)) {
 385                         err = PTR_ERR(sysoff);
 386                         sysoff = NULL;
 387                         break;
 388                 }
 389                 if (sysoff->n_samples > PTP_MAX_SAMPLES) {
 390                         err = -EINVAL;
 391                         break;
 392                 }
 393                 pct = &sysoff->ts[0];
 394                 for (i = 0; i < sysoff->n_samples; i++) {
 395                         ktime_get_real_ts64(&ts);
 396                         pct->sec = ts.tv_sec;
 397                         pct->nsec = ts.tv_nsec;
 398                         pct++;
 399                         if (ops->gettimex64)
 400                                 err = ops->gettimex64(ops, &ts, NULL);
 401                         else
 402                                 err = ops->gettime64(ops, &ts);
 403                         if (err)
 404                                 goto out;
 405                         pct->sec = ts.tv_sec;
 406                         pct->nsec = ts.tv_nsec;
 407                         pct++;
 408                 }
 409                 ktime_get_real_ts64(&ts);
 410                 pct->sec = ts.tv_sec;
 411                 pct->nsec = ts.tv_nsec;
 412                 if (copy_to_user((void __user *)arg, sysoff, sizeof(*sysoff)))
 413                         err = -EFAULT;
 414                 break;
 415
 416         case PTP_PIN_GETFUNC:
 417         case PTP_PIN_GETFUNC2:
 418                 if (copy_from_user(&pd, (void __user *)arg, sizeof(pd))) {
 419                         err = -EFAULT;
 420                         break;
 421                 }
 422                 if ((pd.rsv[0] || pd.rsv[1] || pd.rsv[2]
 423                                 || pd.rsv[3] || pd.rsv[4])
 424                         && cmd == PTP_PIN_GETFUNC2) {
 425                         err = -EINVAL;
 426                         break;
 427                 } else if (cmd == PTP_PIN_GETFUNC) {
 428                         pd.rsv[0] = 0;
 429                         pd.rsv[1] = 0;
 430                         pd.rsv[2] = 0;
 431                         pd.rsv[3] = 0;
 432                         pd.rsv[4] = 0;
 433                 }
 434                 pin_index = pd.index;
 435                 if (pin_index >= ops->n_pins) {
 436                         err = -EINVAL;
 437                         break;
 438                 }
 439                 pin_index = array_index_nospec(pin_index, ops->n_pins);
 440                 if (mutex_lock_interruptible(&ptp->pincfg_mux))
 441                         return -ERESTARTSYS;
 442                 pd = ops->pin_config[pin_index];
 443                 mutex_unlock(&ptp->pincfg_mux);
 444                 if (!err && copy_to_user((void __user *)arg, &pd, sizeof(pd)))
 445                         err = -EFAULT;
 446                 break;
 447
 448         case PTP_PIN_SETFUNC:
 449         case PTP_PIN_SETFUNC2:
 450                 if (copy_from_user(&pd, (void __user *)arg, sizeof(pd))) {
 451                         err = -EFAULT;
 452                         break;
 453                 }
 454                 if ((pd.rsv[0] || pd.rsv[1] || pd.rsv[2]
 455                                 || pd.rsv[3] || pd.rsv[4])
 456                         && cmd == PTP_PIN_SETFUNC2) {
 457                         err = -EINVAL;
 458                         break;
 459                 } else if (cmd == PTP_PIN_SETFUNC) {
 460                         pd.rsv[0] = 0;
 461                         pd.rsv[1] = 0;
 462                         pd.rsv[2] = 0;
 463                         pd.rsv[3] = 0;
 464                         pd.rsv[4] = 0;
 465                 }
 466                 pin_index = pd.index;
 467                 if (pin_index >= ops->n_pins) {
 468                         err = -EINVAL;
 469                         break;
 470                 }
 471                 pin_index = array_index_nospec(pin_index, ops->n_pins);
 472                 if (mutex_lock_interruptible(&ptp->pincfg_mux))
 473                         return -ERESTARTSYS;
 474                 err = ptp_set_pinfunc(ptp, pin_index, pd.func, pd.chan);
 475                 mutex_unlock(&ptp->pincfg_mux);
 476                 break;
 477
 478         case PTP_MASK_CLEAR_ALL:
 479                 bitmap_clear(tsevq->mask, 0, PTP_MAX_CHANNELS);
 480                 break;
 481
 482         case PTP_MASK_EN_SINGLE:
 483                 if (copy_from_user(&i, (void __user *)arg, sizeof(i))) {
 484                         err = -EFAULT;
 485                         break;
 486                 }
 487                 if (i >= PTP_MAX_CHANNELS) {
 488                         err = -EFAULT;
 489                         break;
 490                 }
 491                 set_bit(i, tsevq->mask);
 492                 break;
 493
 494         default:
 495                 err = -ENOTTY;
 496                 break;
 497         }
 498
 499 out:
 500         kfree(extoff);
 501         kfree(sysoff);
 502         return err;
 503 }
 504
 505 __poll_t ptp_poll(struct posix_clock_context *pccontext, struct file *fp,
 506                   poll_table *wait)
 507 {
 508         struct ptp_clock *ptp =
 509                 container_of(pccontext->clk, struct ptp_clock, clock);
 510         struct timestamp_event_queue *queue;
 511
 512         queue = pccontext->private_clkdata;
 513         if (!queue)
 514                 return EPOLLERR;
 515
 516         poll_wait(fp, &ptp->tsev_wq, wait);
 517
 518         return queue_cnt(queue) ? EPOLLIN : 0;
 519 }
 520
 521 #define EXTTS_BUFSIZE (PTP_BUF_TIMESTAMPS * sizeof(struct ptp_extts_event))
 522
 523 ssize_t ptp_read(struct posix_clock_context *pccontext, uint rdflags,
 524                  char __user *buf, size_t cnt)
 525 {
 526         struct ptp_clock *ptp =
 527                 container_of(pccontext->clk, struct ptp_clock, clock);
 528         struct timestamp_event_queue *queue;
 529         struct ptp_extts_event *event;
 530         unsigned long flags;
 531         size_t qcnt, i;
 532         int result;
 533
 534         queue = pccontext->private_clkdata;
 535         if (!queue) {
 536                 result = -EINVAL;
 537                 goto exit;
 538         }
 539
 540         if (cnt % sizeof(struct ptp_extts_event) != 0) {
 541                 result = -EINVAL;
 542                 goto exit;
 543         }
 544
 545         if (cnt > EXTTS_BUFSIZE)
 546                 cnt = EXTTS_BUFSIZE;
 547
 548         cnt = cnt / sizeof(struct ptp_extts_event);
 549
 550         if (wait_event_interruptible(ptp->tsev_wq,
 551                                      ptp->defunct || queue_cnt(queue))) {
 552                 return -ERESTARTSYS;
 553         }
 554
 555         if (ptp->defunct) {
 556                 result = -ENODEV;
 557                 goto exit;
 558         }
 559
 560         event = kmalloc(EXTTS_BUFSIZE, GFP_KERNEL);
 561         if (!event) {
 562                 result = -ENOMEM;
 563                 goto exit;
 564         }
 565
 566         spin_lock_irqsave(&queue->lock, flags);
 567
 568         qcnt = queue_cnt(queue);
 569
 570         if (cnt > qcnt)
 571                 cnt = qcnt;
 572
 573         for (i = 0; i < cnt; i++) {
 574                 event[i] = queue->buf[queue->head];
 575                 /* Paired with READ_ONCE() in queue_cnt() */
 576                 WRITE_ONCE(queue->head, (queue->head + 1) % PTP_MAX_TIMESTAMPS);
 577         }
 578
 579         spin_unlock_irqrestore(&queue->lock, flags);
 580
 581         cnt = cnt * sizeof(struct ptp_extts_event);
 582
 583         result = cnt;
 584         if (copy_to_user(buf, event, cnt)) {
 585                 result = -EFAULT;
 586                 goto free_event;
 587         }
 588
 589 free_event:
 590         kfree(event);
 591 exit:
 592         return result;
 593 }