drivers/ptp/ptp_sysfs.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * PTP 1588 clock support - sysfs interface.
   4  *
   5  * Copyright (C) 2010 OMICRON electronics GmbH
   6  * Copyright 2021 NXP
   7  */
   8 #include <linux/capability.h>
   9 #include <linux/slab.h>
  10
  11 #include "ptp_private.h"
  12
  13 static ssize_t clock_name_show(struct device *dev,
  14                                struct device_attribute *attr, char *page)
  15 {
  16         struct ptp_clock *ptp = dev_get_drvdata(dev);
  17         return sysfs_emit(page, "%s\n", ptp->info->name);
  18 }
  19 static DEVICE_ATTR_RO(clock_name);
  20
  21 static ssize_t max_phase_adjustment_show(struct device *dev,
  22                                          struct device_attribute *attr,
  23                                          char *page)
  24 {
  25         struct ptp_clock *ptp = dev_get_drvdata(dev);
  26
  27         return snprintf(page, PAGE_SIZE - 1, "%d\n",
  28                         ptp->info->getmaxphase(ptp->info));
  29 }
  30 static DEVICE_ATTR_RO(max_phase_adjustment);
  31
  32 #define PTP_SHOW_INT(name, var)                                         \
  33 static ssize_t var##_show(struct device *dev,                           \
  34                            struct device_attribute *attr, char *page)   \
  35 {                                                                       \
  36         struct ptp_clock *ptp = dev_get_drvdata(dev);                   \
  37         return snprintf(page, PAGE_SIZE-1, "%d\n", ptp->info->var);     \
  38 }                                                                       \
  39 static DEVICE_ATTR(name, 0444, var##_show, NULL);
  40
  41 PTP_SHOW_INT(max_adjustment, max_adj);
  42 PTP_SHOW_INT(n_alarms, n_alarm);
  43 PTP_SHOW_INT(n_external_timestamps, n_ext_ts);
  44 PTP_SHOW_INT(n_periodic_outputs, n_per_out);
  45 PTP_SHOW_INT(n_programmable_pins, n_pins);
  46 PTP_SHOW_INT(pps_available, pps);
  47
  48 static ssize_t extts_enable_store(struct device *dev,
  49                                   struct device_attribute *attr,
  50                                   const char *buf, size_t count)
  51 {
  52         struct ptp_clock *ptp = dev_get_drvdata(dev);
  53         struct ptp_clock_info *ops = ptp->info;
  54         struct ptp_clock_request req = { .type = PTP_CLK_REQ_EXTTS };
  55         int cnt, enable;
  56         int err = -EINVAL;
  57
  58         cnt = sscanf(buf, "%u %d", &req.extts.index, &enable);
  59         if (cnt != 2)
  60                 goto out;
  61         if (req.extts.index >= ops->n_ext_ts)
  62                 goto out;
  63
  64         err = ops->enable(ops, &req, enable ? 1 : 0);
  65         if (err)
  66                 goto out;
  67
  68         return count;
  69 out:
  70         return err;
  71 }
  72 static DEVICE_ATTR(extts_enable, 0220, NULL, extts_enable_store);
  73
  74 static ssize_t extts_fifo_show(struct device *dev,
  75                                struct device_attribute *attr, char *page)
  76 {
  77         struct ptp_clock *ptp = dev_get_drvdata(dev);
  78         struct timestamp_event_queue *queue;
  79         struct ptp_extts_event event;
  80         unsigned long flags;
  81         size_t qcnt;
  82         int cnt = 0;
  83
  84         cnt = list_count_nodes(&ptp->tsevqs);
  85         if (cnt <= 0)
  86                 goto out;
  87
  88         /* The sysfs fifo will always draw from the fist queue */
  89         queue = list_first_entry(&ptp->tsevqs, struct timestamp_event_queue,
  90                                  qlist);
  91
  92         memset(&event, 0, sizeof(event));
  93         spin_lock_irqsave(&queue->lock, flags);
  94         qcnt = queue_cnt(queue);
  95         if (qcnt) {
  96                 event = queue->buf[queue->head];
  97                 /* Paired with READ_ONCE() in queue_cnt() */
  98                 WRITE_ONCE(queue->head, (queue->head + 1) % PTP_MAX_TIMESTAMPS);
  99         }
 100         spin_unlock_irqrestore(&queue->lock, flags);
 101
 102         if (!qcnt)
 103                 goto out;
 104
 105         cnt = snprintf(page, PAGE_SIZE, "%u %lld %u\n",
 106                        event.index, event.t.sec, event.t.nsec);
 107 out:
 108         return cnt;
 109 }
 110 static DEVICE_ATTR(fifo, 0444, extts_fifo_show, NULL);
 111
 112 static ssize_t period_store(struct device *dev,
 113                             struct device_attribute *attr,
 114                             const char *buf, size_t count)
 115 {
 116         struct ptp_clock *ptp = dev_get_drvdata(dev);
 117         struct ptp_clock_info *ops = ptp->info;
 118         struct ptp_clock_request req = { .type = PTP_CLK_REQ_PEROUT };
 119         int cnt, enable, err = -EINVAL;
 120
 121         cnt = sscanf(buf, "%u %lld %u %lld %u", &req.perout.index,
 122                      &req.perout.start.sec, &req.perout.start.nsec,
 123                      &req.perout.period.sec, &req.perout.period.nsec);
 124         if (cnt != 5)
 125                 goto out;
 126         if (req.perout.index >= ops->n_per_out)
 127                 goto out;
 128
 129         enable = req.perout.period.sec || req.perout.period.nsec;
 130         err = ops->enable(ops, &req, enable);
 131         if (err)
 132                 goto out;
 133
 134         return count;
 135 out:
 136         return err;
 137 }
 138 static DEVICE_ATTR(period, 0220, NULL, period_store);
 139
 140 static ssize_t pps_enable_store(struct device *dev,
 141                                 struct device_attribute *attr,
 142                                 const char *buf, size_t count)
 143 {
 144         struct ptp_clock *ptp = dev_get_drvdata(dev);
 145         struct ptp_clock_info *ops = ptp->info;
 146         struct ptp_clock_request req = { .type = PTP_CLK_REQ_PPS };
 147         int cnt, enable;
 148         int err = -EINVAL;
 149
 150         if (!capable(CAP_SYS_TIME))
 151                 return -EPERM;
 152
 153         cnt = sscanf(buf, "%d", &enable);
 154         if (cnt != 1)
 155                 goto out;
 156
 157         err = ops->enable(ops, &req, enable ? 1 : 0);
 158         if (err)
 159                 goto out;
 160
 161         return count;
 162 out:
 163         return err;
 164 }
 165 static DEVICE_ATTR(pps_enable, 0220, NULL, pps_enable_store);
 166
 167 static int unregister_vclock(struct device *dev, void *data)
 168 {
 169         struct ptp_clock *ptp = dev_get_drvdata(dev);
 170         struct ptp_clock_info *info = ptp->info;
 171         struct ptp_vclock *vclock;
 172         u32 *num = data;
 173
 174         vclock = info_to_vclock(info);
 175         dev_info(dev->parent, "delete virtual clock ptp%d\n",
 176                  vclock->clock->index);
 177
 178         ptp_vclock_unregister(vclock);
 179         (*num)--;
 180
 181         /* For break. Not error. */
 182         if (*num == 0)
 183                 return -EINVAL;
 184
 185         return 0;
 186 }
 187
 188 static ssize_t n_vclocks_show(struct device *dev,
 189                               struct device_attribute *attr, char *page)
 190 {
 191         struct ptp_clock *ptp = dev_get_drvdata(dev);
 192         ssize_t size;
 193
 194         if (mutex_lock_interruptible(&ptp->n_vclocks_mux))
 195                 return -ERESTARTSYS;
 196
 197         size = snprintf(page, PAGE_SIZE - 1, "%u\n", ptp->n_vclocks);
 198
 199         mutex_unlock(&ptp->n_vclocks_mux);
 200
 201         return size;
 202 }
 203
 204 static ssize_t n_vclocks_store(struct device *dev,
 205                                struct device_attribute *attr,
 206                                const char *buf, size_t count)
 207 {
 208         struct ptp_clock *ptp = dev_get_drvdata(dev);
 209         struct ptp_vclock *vclock;
 210         int err = -EINVAL;
 211         u32 num, i;
 212
 213         if (kstrtou32(buf, 0, &num))
 214                 return err;
 215
 216         if (mutex_lock_interruptible(&ptp->n_vclocks_mux))
 217                 return -ERESTARTSYS;
 218
 219         if (num > ptp->max_vclocks) {
 220                 dev_err(dev, "max value is %d\n", ptp->max_vclocks);
 221                 goto out;
 222         }
 223
 224         /* Need to create more vclocks */
 225         if (num > ptp->n_vclocks) {
 226                 for (i = 0; i < num - ptp->n_vclocks; i++) {
 227                         vclock = ptp_vclock_register(ptp);
 228                         if (!vclock)
 229                                 goto out;
 230
 231                         *(ptp->vclock_index + ptp->n_vclocks + i) =
 232                                 vclock->clock->index;
 233
 234                         dev_info(dev, "new virtual clock ptp%d\n",
 235                                  vclock->clock->index);
 236                 }
 237         }
 238
 239         /* Need to delete vclocks */
 240         if (num < ptp->n_vclocks) {
 241                 i = ptp->n_vclocks - num;
 242                 device_for_each_child_reverse(dev, &i,
 243                                               unregister_vclock);
 244
 245                 for (i = 1; i <= ptp->n_vclocks - num; i++)
 246                         *(ptp->vclock_index + ptp->n_vclocks - i) = -1;
 247         }
 248
 249         /* Need to inform about changed physical clock behavior */
 250         if (!ptp->has_cycles) {
 251                 if (num == 0)
 252                         dev_info(dev, "only physical clock in use now\n");
 253                 else
 254                         dev_info(dev, "guarantee physical clock free running\n");
 255         }
 256
 257         ptp->n_vclocks = num;
 258         mutex_unlock(&ptp->n_vclocks_mux);
 259
 260         return count;
 261 out:
 262         mutex_unlock(&ptp->n_vclocks_mux);
 263         return err;
 264 }
 265 static DEVICE_ATTR_RW(n_vclocks);
 266
 267 static ssize_t max_vclocks_show(struct device *dev,
 268                                 struct device_attribute *attr, char *page)
 269 {
 270         struct ptp_clock *ptp = dev_get_drvdata(dev);
 271         ssize_t size;
 272
 273         size = snprintf(page, PAGE_SIZE - 1, "%u\n", ptp->max_vclocks);
 274
 275         return size;
 276 }
 277
 278 static ssize_t max_vclocks_store(struct device *dev,
 279                                  struct device_attribute *attr,
 280                                  const char *buf, size_t count)
 281 {
 282         struct ptp_clock *ptp = dev_get_drvdata(dev);
 283         unsigned int *vclock_index;
 284         int err = -EINVAL;
 285         size_t size;
 286         u32 max;
 287
 288         if (kstrtou32(buf, 0, &max) || max == 0)
 289                 return -EINVAL;
 290
 291         if (max == ptp->max_vclocks)
 292                 return count;
 293
 294         if (mutex_lock_interruptible(&ptp->n_vclocks_mux))
 295                 return -ERESTARTSYS;
 296
 297         if (max < ptp->n_vclocks)
 298                 goto out;
 299
 300         size = sizeof(int) * max;
 301         vclock_index = kzalloc(size, GFP_KERNEL);
 302         if (!vclock_index) {
 303                 err = -ENOMEM;
 304                 goto out;
 305         }
 306
 307         size = sizeof(int) * ptp->n_vclocks;
 308         memcpy(vclock_index, ptp->vclock_index, size);
 309
 310         kfree(ptp->vclock_index);
 311         ptp->vclock_index = vclock_index;
 312         ptp->max_vclocks = max;
 313
 314         mutex_unlock(&ptp->n_vclocks_mux);
 315
 316         return count;
 317 out:
 318         mutex_unlock(&ptp->n_vclocks_mux);
 319         return err;
 320 }
 321 static DEVICE_ATTR_RW(max_vclocks);
 322
 323 static struct attribute *ptp_attrs[] = {
 324         &dev_attr_clock_name.attr,
 325
 326         &dev_attr_max_adjustment.attr,
 327         &dev_attr_max_phase_adjustment.attr,
 328         &dev_attr_n_alarms.attr,
 329         &dev_attr_n_external_timestamps.attr,
 330         &dev_attr_n_periodic_outputs.attr,
 331         &dev_attr_n_programmable_pins.attr,
 332         &dev_attr_pps_available.attr,
 333
 334         &dev_attr_extts_enable.attr,
 335         &dev_attr_fifo.attr,
 336         &dev_attr_period.attr,
 337         &dev_attr_pps_enable.attr,
 338         &dev_attr_n_vclocks.attr,
 339         &dev_attr_max_vclocks.attr,
 340         NULL
 341 };
 342
 343 static umode_t ptp_is_attribute_visible(struct kobject *kobj,
 344                                         struct attribute *attr, int n)
 345 {
 346         struct device *dev = kobj_to_dev(kobj);
 347         struct ptp_clock *ptp = dev_get_drvdata(dev);
 348         struct ptp_clock_info *info = ptp->info;
 349         umode_t mode = attr->mode;
 350
 351         if (attr == &dev_attr_extts_enable.attr ||
 352             attr == &dev_attr_fifo.attr) {
 353                 if (!info->n_ext_ts)
 354                         mode = 0;
 355         } else if (attr == &dev_attr_period.attr) {
 356                 if (!info->n_per_out)
 357                         mode = 0;
 358         } else if (attr == &dev_attr_pps_enable.attr) {
 359                 if (!info->pps)
 360                         mode = 0;
 361         } else if (attr == &dev_attr_n_vclocks.attr ||
 362                    attr == &dev_attr_max_vclocks.attr) {
 363                 if (ptp->is_virtual_clock)
 364                         mode = 0;
 365         } else if (attr == &dev_attr_max_phase_adjustment.attr) {
 366                 if (!info->adjphase || !info->getmaxphase)
 367                         mode = 0;
 368         }
 369
 370         return mode;
 371 }
 372
 373 static const struct attribute_group ptp_group = {
 374         .is_visible     = ptp_is_attribute_visible,
 375         .attrs          = ptp_attrs,
 376 };
 377
 378 const struct attribute_group *ptp_groups[] = {
 379         &ptp_group,
 380         NULL
 381 };
 382
 383 static int ptp_pin_name2index(struct ptp_clock *ptp, const char *name)
 384 {
 385         int i;
 386         for (i = 0; i < ptp->info->n_pins; i++) {
 387                 if (!strcmp(ptp->info->pin_config[i].name, name))
 388                         return i;
 389         }
 390         return -1;
 391 }
 392
 393 static ssize_t ptp_pin_show(struct device *dev, struct device_attribute *attr,
 394                             char *page)
 395 {
 396         struct ptp_clock *ptp = dev_get_drvdata(dev);
 397         unsigned int func, chan;
 398         int index;
 399
 400         index = ptp_pin_name2index(ptp, attr->attr.name);
 401         if (index < 0)
 402                 return -EINVAL;
 403
 404         if (mutex_lock_interruptible(&ptp->pincfg_mux))
 405                 return -ERESTARTSYS;
 406
 407         func = ptp->info->pin_config[index].func;
 408         chan = ptp->info->pin_config[index].chan;
 409
 410         mutex_unlock(&ptp->pincfg_mux);
 411
 412         return sysfs_emit(page, "%u %u\n", func, chan);
 413 }
 414
 415 static ssize_t ptp_pin_store(struct device *dev, struct device_attribute *attr,
 416                              const char *buf, size_t count)
 417 {
 418         struct ptp_clock *ptp = dev_get_drvdata(dev);
 419         unsigned int func, chan;
 420         int cnt, err, index;
 421
 422         cnt = sscanf(buf, "%u %u", &func, &chan);
 423         if (cnt != 2)
 424                 return -EINVAL;
 425
 426         index = ptp_pin_name2index(ptp, attr->attr.name);
 427         if (index < 0)
 428                 return -EINVAL;
 429
 430         if (mutex_lock_interruptible(&ptp->pincfg_mux))
 431                 return -ERESTARTSYS;
 432         err = ptp_set_pinfunc(ptp, index, func, chan);
 433         mutex_unlock(&ptp->pincfg_mux);
 434         if (err)
 435                 return err;
 436
 437         return count;
 438 }
 439
 440 int ptp_populate_pin_groups(struct ptp_clock *ptp)
 441 {
 442         struct ptp_clock_info *info = ptp->info;
 443         int err = -ENOMEM, i, n_pins = info->n_pins;
 444
 445         if (!n_pins)
 446                 return 0;
 447
 448         ptp->pin_dev_attr = kcalloc(n_pins, sizeof(*ptp->pin_dev_attr),
 449                                     GFP_KERNEL);
 450         if (!ptp->pin_dev_attr)
 451                 goto no_dev_attr;
 452
 453         ptp->pin_attr = kcalloc(1 + n_pins, sizeof(*ptp->pin_attr), GFP_KERNEL);
 454         if (!ptp->pin_attr)
 455                 goto no_pin_attr;
 456
 457         for (i = 0; i < n_pins; i++) {
 458                 struct device_attribute *da = &ptp->pin_dev_attr[i];
 459                 sysfs_attr_init(&da->attr);
 460                 da->attr.name = info->pin_config[i].name;
 461                 da->attr.mode = 0644;
 462                 da->show = ptp_pin_show;
 463                 da->store = ptp_pin_store;
 464                 ptp->pin_attr[i] = &da->attr;
 465         }
 466
 467         ptp->pin_attr_group.name = "pins";
 468         ptp->pin_attr_group.attrs = ptp->pin_attr;
 469
 470         ptp->pin_attr_groups[0] = &ptp->pin_attr_group;
 471
 472         return 0;
 473
 474 no_pin_attr:
 475         kfree(ptp->pin_dev_attr);
 476 no_dev_attr:
 477         return err;
 478 }
 479
 480 void ptp_cleanup_pin_groups(struct ptp_clock *ptp)
 481 {
 482         kfree(ptp->pin_attr);
 483         kfree(ptp->pin_dev_attr);
 484 }