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