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                 if (copy_to_user((void __user *)arg, &caps, sizeof(caps)))
 141                         err = -EFAULT;
 142                 break;
 143
 144         case PTP_EXTTS_REQUEST:
 145         case PTP_EXTTS_REQUEST2:
 146                 memset(&req, 0, sizeof(req));
 147
 148                 if (copy_from_user(&req.extts, (void __user *)arg,
 149                                    sizeof(req.extts))) {
 150                         err = -EFAULT;
 151                         break;
 152                 }
 153                 if (cmd == PTP_EXTTS_REQUEST2) {
 154                         /* Tell the drivers to check the flags carefully. */
 155                         req.extts.flags |= PTP_STRICT_FLAGS;
 156                         /* Make sure no reserved bit is set. */
 157                         if ((req.extts.flags & ~PTP_EXTTS_VALID_FLAGS) ||
 158                             req.extts.rsv[0] || req.extts.rsv[1]) {
 159                                 err = -EINVAL;
 160                                 break;
 161                         }
 162                         /* Ensure one of the rising/falling edge bits is set. */
 163                         if ((req.extts.flags & PTP_ENABLE_FEATURE) &&
 164                             (req.extts.flags & PTP_EXTTS_EDGES) == 0) {
 165                                 err = -EINVAL;
 166                                 break;
 167                         }
 168                 } else if (cmd == PTP_EXTTS_REQUEST) {
 169                         req.extts.flags &= PTP_EXTTS_V1_VALID_FLAGS;
 170                         req.extts.rsv[0] = 0;
 171                         req.extts.rsv[1] = 0;
 172                 }
 173                 if (req.extts.index >= ops->n_ext_ts) {
 174                         err = -EINVAL;
 175                         break;
 176                 }
 177                 req.type = PTP_CLK_REQ_EXTTS;
 178                 enable = req.extts.flags & PTP_ENABLE_FEATURE ? 1 : 0;
 179                 if (mutex_lock_interruptible(&ptp->pincfg_mux))
 180                         return -ERESTARTSYS;
 181                 err = ops->enable(ops, &req, enable);
 182                 mutex_unlock(&ptp->pincfg_mux);
 183                 break;
 184
 185         case PTP_PEROUT_REQUEST:
 186         case PTP_PEROUT_REQUEST2:
 187                 memset(&req, 0, sizeof(req));
 188
 189                 if (copy_from_user(&req.perout, (void __user *)arg,
 190                                    sizeof(req.perout))) {
 191                         err = -EFAULT;
 192                         break;
 193                 }
 194                 if (cmd == PTP_PEROUT_REQUEST2) {
 195                         struct ptp_perout_request *perout = &req.perout;
 196
 197                         if (perout->flags & ~PTP_PEROUT_VALID_FLAGS) {
 198                                 err = -EINVAL;
 199                                 break;
 200                         }
 201                         /*
 202                          * The "on" field has undefined meaning if
 203                          * PTP_PEROUT_DUTY_CYCLE isn't set, we must still treat
 204                          * it as reserved, which must be set to zero.
 205                          */
 206                         if (!(perout->flags & PTP_PEROUT_DUTY_CYCLE) &&
 207                             (perout->rsv[0] || perout->rsv[1] ||
 208                              perout->rsv[2] || perout->rsv[3])) {
 209                                 err = -EINVAL;
 210                                 break;
 211                         }
 212                         if (perout->flags & PTP_PEROUT_DUTY_CYCLE) {
 213                                 /* The duty cycle must be subunitary. */
 214                                 if (perout->on.sec > perout->period.sec ||
 215                                     (perout->on.sec == perout->period.sec &&
 216                                      perout->on.nsec > perout->period.nsec)) {
 217                                         err = -ERANGE;
 218                                         break;
 219                                 }
 220                         }
 221                         if (perout->flags & PTP_PEROUT_PHASE) {
 222                                 /*
 223                                  * The phase should be specified modulo the
 224                                  * period, therefore anything equal or larger
 225                                  * than 1 period is invalid.
 226                                  */
 227                                 if (perout->phase.sec > perout->period.sec ||
 228                                     (perout->phase.sec == perout->period.sec &&
 229                                      perout->phase.nsec >= perout->period.nsec)) {
 230                                         err = -ERANGE;
 231                                         break;
 232                                 }
 233                         }
 234                 } else if (cmd == PTP_PEROUT_REQUEST) {
 235                         req.perout.flags &= PTP_PEROUT_V1_VALID_FLAGS;
 236                         req.perout.rsv[0] = 0;
 237                         req.perout.rsv[1] = 0;
 238                         req.perout.rsv[2] = 0;
 239                         req.perout.rsv[3] = 0;
 240                 }
 241                 if (req.perout.index >= ops->n_per_out) {
 242                         err = -EINVAL;
 243                         break;
 244                 }
 245                 req.type = PTP_CLK_REQ_PEROUT;
 246                 enable = req.perout.period.sec || req.perout.period.nsec;
 247                 if (mutex_lock_interruptible(&ptp->pincfg_mux))
 248                         return -ERESTARTSYS;
 249                 err = ops->enable(ops, &req, enable);
 250                 mutex_unlock(&ptp->pincfg_mux);
 251                 break;
 252
 253         case PTP_ENABLE_PPS:
 254         case PTP_ENABLE_PPS2:
 255                 memset(&req, 0, sizeof(req));
 256
 257                 if (!capable(CAP_SYS_TIME))
 258                         return -EPERM;
 259                 req.type = PTP_CLK_REQ_PPS;
 260                 enable = arg ? 1 : 0;
 261                 if (mutex_lock_interruptible(&ptp->pincfg_mux))
 262                         return -ERESTARTSYS;
 263                 err = ops->enable(ops, &req, enable);
 264                 mutex_unlock(&ptp->pincfg_mux);
 265                 break;
 266
 267         case PTP_SYS_OFFSET_PRECISE:
 268         case PTP_SYS_OFFSET_PRECISE2:
 269                 if (!ptp->info->getcrosststamp) {
 270                         err = -EOPNOTSUPP;
 271                         break;
 272                 }
 273                 err = ptp->info->getcrosststamp(ptp->info, &xtstamp);
 274                 if (err)
 275                         break;
 276
 277                 memset(&precise_offset, 0, sizeof(precise_offset));
 278                 ts = ktime_to_timespec64(xtstamp.device);
 279                 precise_offset.device.sec = ts.tv_sec;
 280                 precise_offset.device.nsec = ts.tv_nsec;
 281                 ts = ktime_to_timespec64(xtstamp.sys_realtime);
 282                 precise_offset.sys_realtime.sec = ts.tv_sec;
 283                 precise_offset.sys_realtime.nsec = ts.tv_nsec;
 284                 ts = ktime_to_timespec64(xtstamp.sys_monoraw);
 285                 precise_offset.sys_monoraw.sec = ts.tv_sec;
 286                 precise_offset.sys_monoraw.nsec = ts.tv_nsec;
 287                 if (copy_to_user((void __user *)arg, &precise_offset,
 288                                  sizeof(precise_offset)))
 289                         err = -EFAULT;
 290                 break;
 291
 292         case PTP_SYS_OFFSET_EXTENDED:
 293         case PTP_SYS_OFFSET_EXTENDED2:
 294                 if (!ptp->info->gettimex64) {
 295                         err = -EOPNOTSUPP;
 296                         break;
 297                 }
 298                 extoff = memdup_user((void __user *)arg, sizeof(*extoff));
 299                 if (IS_ERR(extoff)) {
 300                         err = PTR_ERR(extoff);
 301                         extoff = NULL;
 302                         break;
 303                 }
 304                 if (extoff->n_samples > PTP_MAX_SAMPLES
 305                     || extoff->rsv[0] || extoff->rsv[1] || extoff->rsv[2]) {
 306                         err = -EINVAL;
 307                         break;
 308                 }
 309                 for (i = 0; i < extoff->n_samples; i++) {
 310                         err = ptp->info->gettimex64(ptp->info, &ts, &sts);
 311                         if (err)
 312                                 goto out;
 313                         extoff->ts[i][0].sec = sts.pre_ts.tv_sec;
 314                         extoff->ts[i][0].nsec = sts.pre_ts.tv_nsec;
 315                         extoff->ts[i][1].sec = ts.tv_sec;
 316                         extoff->ts[i][1].nsec = ts.tv_nsec;
 317                         extoff->ts[i][2].sec = sts.post_ts.tv_sec;
 318                         extoff->ts[i][2].nsec = sts.post_ts.tv_nsec;
 319                 }
 320                 if (copy_to_user((void __user *)arg, extoff, sizeof(*extoff)))
 321                         err = -EFAULT;
 322                 break;
 323
 324         case PTP_SYS_OFFSET:
 325         case PTP_SYS_OFFSET2:
 326                 sysoff = memdup_user((void __user *)arg, sizeof(*sysoff));
 327                 if (IS_ERR(sysoff)) {
 328                         err = PTR_ERR(sysoff);
 329                         sysoff = NULL;
 330                         break;
 331                 }
 332                 if (sysoff->n_samples > PTP_MAX_SAMPLES) {
 333                         err = -EINVAL;
 334                         break;
 335                 }
 336                 pct = &sysoff->ts[0];
 337                 for (i = 0; i < sysoff->n_samples; i++) {
 338                         ktime_get_real_ts64(&ts);
 339                         pct->sec = ts.tv_sec;
 340                         pct->nsec = ts.tv_nsec;
 341                         pct++;
 342                         if (ops->gettimex64)
 343                                 err = ops->gettimex64(ops, &ts, NULL);
 344                         else
 345                                 err = ops->gettime64(ops, &ts);
 346                         if (err)
 347                                 goto out;
 348                         pct->sec = ts.tv_sec;
 349                         pct->nsec = ts.tv_nsec;
 350                         pct++;
 351                 }
 352                 ktime_get_real_ts64(&ts);
 353                 pct->sec = ts.tv_sec;
 354                 pct->nsec = ts.tv_nsec;
 355                 if (copy_to_user((void __user *)arg, sysoff, sizeof(*sysoff)))
 356                         err = -EFAULT;
 357                 break;
 358
 359         case PTP_PIN_GETFUNC:
 360         case PTP_PIN_GETFUNC2:
 361                 if (copy_from_user(&pd, (void __user *)arg, sizeof(pd))) {
 362                         err = -EFAULT;
 363                         break;
 364                 }
 365                 if ((pd.rsv[0] || pd.rsv[1] || pd.rsv[2]
 366                                 || pd.rsv[3] || pd.rsv[4])
 367                         && cmd == PTP_PIN_GETFUNC2) {
 368                         err = -EINVAL;
 369                         break;
 370                 } else if (cmd == PTP_PIN_GETFUNC) {
 371                         pd.rsv[0] = 0;
 372                         pd.rsv[1] = 0;
 373                         pd.rsv[2] = 0;
 374                         pd.rsv[3] = 0;
 375                         pd.rsv[4] = 0;
 376                 }
 377                 pin_index = pd.index;
 378                 if (pin_index >= ops->n_pins) {
 379                         err = -EINVAL;
 380                         break;
 381                 }
 382                 pin_index = array_index_nospec(pin_index, ops->n_pins);
 383                 if (mutex_lock_interruptible(&ptp->pincfg_mux))
 384                         return -ERESTARTSYS;
 385                 pd = ops->pin_config[pin_index];
 386                 mutex_unlock(&ptp->pincfg_mux);
 387                 if (!err && copy_to_user((void __user *)arg, &pd, sizeof(pd)))
 388                         err = -EFAULT;
 389                 break;
 390
 391         case PTP_PIN_SETFUNC:
 392         case PTP_PIN_SETFUNC2:
 393                 if (copy_from_user(&pd, (void __user *)arg, sizeof(pd))) {
 394                         err = -EFAULT;
 395                         break;
 396                 }
 397                 if ((pd.rsv[0] || pd.rsv[1] || pd.rsv[2]
 398                                 || pd.rsv[3] || pd.rsv[4])
 399                         && cmd == PTP_PIN_SETFUNC2) {
 400                         err = -EINVAL;
 401                         break;
 402                 } else if (cmd == PTP_PIN_SETFUNC) {
 403                         pd.rsv[0] = 0;
 404                         pd.rsv[1] = 0;
 405                         pd.rsv[2] = 0;
 406                         pd.rsv[3] = 0;
 407                         pd.rsv[4] = 0;
 408                 }
 409                 pin_index = pd.index;
 410                 if (pin_index >= ops->n_pins) {
 411                         err = -EINVAL;
 412                         break;
 413                 }
 414                 pin_index = array_index_nospec(pin_index, ops->n_pins);
 415                 if (mutex_lock_interruptible(&ptp->pincfg_mux))
 416                         return -ERESTARTSYS;
 417                 err = ptp_set_pinfunc(ptp, pin_index, pd.func, pd.chan);
 418                 mutex_unlock(&ptp->pincfg_mux);
 419                 break;
 420
 421         default:
 422                 err = -ENOTTY;
 423                 break;
 424         }
 425
 426 out:
 427         kfree(extoff);
 428         kfree(sysoff);
 429         return err;
 430 }
 431
 432 __poll_t ptp_poll(struct posix_clock *pc, struct file *fp, poll_table *wait)
 433 {
 434         struct ptp_clock *ptp = container_of(pc, struct ptp_clock, clock);
 435
 436         poll_wait(fp, &ptp->tsev_wq, wait);
 437
 438         return queue_cnt(&ptp->tsevq) ? EPOLLIN : 0;
 439 }
 440
 441 #define EXTTS_BUFSIZE (PTP_BUF_TIMESTAMPS * sizeof(struct ptp_extts_event))
 442
 443 ssize_t ptp_read(struct posix_clock *pc,
 444                  uint rdflags, char __user *buf, size_t cnt)
 445 {
 446         struct ptp_clock *ptp = container_of(pc, struct ptp_clock, clock);
 447         struct timestamp_event_queue *queue = &ptp->tsevq;
 448         struct ptp_extts_event *event;
 449         unsigned long flags;
 450         size_t qcnt, i;
 451         int result;
 452
 453         if (cnt % sizeof(struct ptp_extts_event) != 0)
 454                 return -EINVAL;
 455
 456         if (cnt > EXTTS_BUFSIZE)
 457                 cnt = EXTTS_BUFSIZE;
 458
 459         cnt = cnt / sizeof(struct ptp_extts_event);
 460
 461         if (mutex_lock_interruptible(&ptp->tsevq_mux))
 462                 return -ERESTARTSYS;
 463
 464         if (wait_event_interruptible(ptp->tsev_wq,
 465                                      ptp->defunct || queue_cnt(queue))) {
 466                 mutex_unlock(&ptp->tsevq_mux);
 467                 return -ERESTARTSYS;
 468         }
 469
 470         if (ptp->defunct) {
 471                 mutex_unlock(&ptp->tsevq_mux);
 472                 return -ENODEV;
 473         }
 474
 475         event = kmalloc(EXTTS_BUFSIZE, GFP_KERNEL);
 476         if (!event) {
 477                 mutex_unlock(&ptp->tsevq_mux);
 478                 return -ENOMEM;
 479         }
 480
 481         spin_lock_irqsave(&queue->lock, flags);
 482
 483         qcnt = queue_cnt(queue);
 484
 485         if (cnt > qcnt)
 486                 cnt = qcnt;
 487
 488         for (i = 0; i < cnt; i++) {
 489                 event[i] = queue->buf[queue->head];
 490                 queue->head = (queue->head + 1) % PTP_MAX_TIMESTAMPS;
 491         }
 492
 493         spin_unlock_irqrestore(&queue->lock, flags);
 494
 495         cnt = cnt * sizeof(struct ptp_extts_event);
 496
 497         mutex_unlock(&ptp->tsevq_mux);
 498
 499         result = cnt;
 500         if (copy_to_user(buf, event, cnt))
 501                 result = -EFAULT;
 502
 503         kfree(event);
 504         return result;
 505 }