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