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