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