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                 /* Paired with READ_ONCE() in queue_cnt() */
  94                 WRITE_ONCE(queue->head, (queue->head + 1) % PTP_MAX_TIMESTAMPS);
  95         }
  96         spin_unlock_irqrestore(&queue->lock, flags);
  97
  98         if (!qcnt)
  99                 goto out;
 100
 101         cnt = snprintf(page, PAGE_SIZE, "%u %lld %u\n",
 102                        event.index, event.t.sec, event.t.nsec);
 103 out:
 104         mutex_unlock(&ptp->tsevq_mux);
 105         return cnt;
 106 }
 107 static DEVICE_ATTR(fifo, 0444, extts_fifo_show, NULL);
 108
 109 static ssize_t period_store(struct device *dev,
 110                             struct device_attribute *attr,
 111                             const char *buf, size_t count)
 112 {
 113         struct ptp_clock *ptp = dev_get_drvdata(dev);
 114         struct ptp_clock_info *ops = ptp->info;
 115         struct ptp_clock_request req = { .type = PTP_CLK_REQ_PEROUT };
 116         int cnt, enable, err = -EINVAL;
 117
 118         cnt = sscanf(buf, "%u %lld %u %lld %u", &req.perout.index,
 119                      &req.perout.start.sec, &req.perout.start.nsec,
 120                      &req.perout.period.sec, &req.perout.period.nsec);
 121         if (cnt != 5)
 122                 goto out;
 123         if (req.perout.index >= ops->n_per_out)
 124                 goto out;
 125
 126         enable = req.perout.period.sec || req.perout.period.nsec;
 127         err = ops->enable(ops, &req, enable);
 128         if (err)
 129                 goto out;
 130
 131         return count;
 132 out:
 133         return err;
 134 }
 135 static DEVICE_ATTR(period, 0220, NULL, period_store);
 136
 137 static ssize_t pps_enable_store(struct device *dev,
 138                                 struct device_attribute *attr,
 139                                 const char *buf, size_t count)
 140 {
 141         struct ptp_clock *ptp = dev_get_drvdata(dev);
 142         struct ptp_clock_info *ops = ptp->info;
 143         struct ptp_clock_request req = { .type = PTP_CLK_REQ_PPS };
 144         int cnt, enable;
 145         int err = -EINVAL;
 146
 147         if (!capable(CAP_SYS_TIME))
 148                 return -EPERM;
 149
 150         cnt = sscanf(buf, "%d", &enable);
 151         if (cnt != 1)
 152                 goto out;
 153
 154         err = ops->enable(ops, &req, enable ? 1 : 0);
 155         if (err)
 156                 goto out;
 157
 158         return count;
 159 out:
 160         return err;
 161 }
 162 static DEVICE_ATTR(pps_enable, 0220, NULL, pps_enable_store);
 163
 164 static int unregister_vclock(struct device *dev, void *data)
 165 {
 166         struct ptp_clock *ptp = dev_get_drvdata(dev);
 167         struct ptp_clock_info *info = ptp->info;
 168         struct ptp_vclock *vclock;
 169         u32 *num = data;
 170
 171         vclock = info_to_vclock(info);
 172         dev_info(dev->parent, "delete virtual clock ptp%d\n",
 173                  vclock->clock->index);
 174
 175         ptp_vclock_unregister(vclock);
 176         (*num)--;
 177
 178         /* For break. Not error. */
 179         if (*num == 0)
 180                 return -EINVAL;
 181
 182         return 0;
 183 }
 184
 185 static ssize_t n_vclocks_show(struct device *dev,
 186                               struct device_attribute *attr, char *page)
 187 {
 188         struct ptp_clock *ptp = dev_get_drvdata(dev);
 189         ssize_t size;
 190
 191         if (mutex_lock_interruptible(&ptp->n_vclocks_mux))
 192                 return -ERESTARTSYS;
 193
 194         size = snprintf(page, PAGE_SIZE - 1, "%u\n", ptp->n_vclocks);
 195
 196         mutex_unlock(&ptp->n_vclocks_mux);
 197
 198         return size;
 199 }
 200
 201 static ssize_t n_vclocks_store(struct device *dev,
 202                                struct device_attribute *attr,
 203                                const char *buf, size_t count)
 204 {
 205         struct ptp_clock *ptp = dev_get_drvdata(dev);
 206         struct ptp_vclock *vclock;
 207         int err = -EINVAL;
 208         u32 num, i;
 209
 210         if (kstrtou32(buf, 0, &num))
 211                 return err;
 212
 213         if (mutex_lock_interruptible(&ptp->n_vclocks_mux))
 214                 return -ERESTARTSYS;
 215
 216         if (num > ptp->max_vclocks) {
 217                 dev_err(dev, "max value is %d\n", ptp->max_vclocks);
 218                 goto out;
 219         }
 220
 221         /* Need to create more vclocks */
 222         if (num > ptp->n_vclocks) {
 223                 for (i = 0; i < num - ptp->n_vclocks; i++) {
 224                         vclock = ptp_vclock_register(ptp);
 225                         if (!vclock)
 226                                 goto out;
 227
 228                         *(ptp->vclock_index + ptp->n_vclocks + i) =
 229                                 vclock->clock->index;
 230
 231                         dev_info(dev, "new virtual clock ptp%d\n",
 232                                  vclock->clock->index);
 233                 }
 234         }
 235
 236         /* Need to delete vclocks */
 237         if (num < ptp->n_vclocks) {
 238                 i = ptp->n_vclocks - num;
 239                 device_for_each_child_reverse(dev, &i,
 240                                               unregister_vclock);
 241
 242                 for (i = 1; i <= ptp->n_vclocks - num; i++)
 243                         *(ptp->vclock_index + ptp->n_vclocks - i) = -1;
 244         }
 245
 246         /* Need to inform about changed physical clock behavior */
 247         if (!ptp->has_cycles) {
 248                 if (num == 0)
 249                         dev_info(dev, "only physical clock in use now\n");
 250                 else
 251                         dev_info(dev, "guarantee physical clock free running\n");
 252         }
 253
 254         ptp->n_vclocks = num;
 255         mutex_unlock(&ptp->n_vclocks_mux);
 256
 257         return count;
 258 out:
 259         mutex_unlock(&ptp->n_vclocks_mux);
 260         return err;
 261 }
 262 static DEVICE_ATTR_RW(n_vclocks);
 263
 264 static ssize_t max_vclocks_show(struct device *dev,
 265                                 struct device_attribute *attr, char *page)
 266 {
 267         struct ptp_clock *ptp = dev_get_drvdata(dev);
 268         ssize_t size;
 269
 270         size = snprintf(page, PAGE_SIZE - 1, "%u\n", ptp->max_vclocks);
 271
 272         return size;
 273 }
 274
 275 static ssize_t max_vclocks_store(struct device *dev,
 276                                  struct device_attribute *attr,
 277                                  const char *buf, size_t count)
 278 {
 279         struct ptp_clock *ptp = dev_get_drvdata(dev);
 280         unsigned int *vclock_index;
 281         int err = -EINVAL;
 282         size_t size;
 283         u32 max;
 284
 285         if (kstrtou32(buf, 0, &max) || max == 0)
 286                 return -EINVAL;
 287
 288         if (max == ptp->max_vclocks)
 289                 return count;
 290
 291         if (mutex_lock_interruptible(&ptp->n_vclocks_mux))
 292                 return -ERESTARTSYS;
 293
 294         if (max < ptp->n_vclocks)
 295                 goto out;
 296
 297         size = sizeof(int) * max;
 298         vclock_index = kzalloc(size, GFP_KERNEL);
 299         if (!vclock_index) {
 300                 err = -ENOMEM;
 301                 goto out;
 302         }
 303
 304         size = sizeof(int) * ptp->n_vclocks;
 305         memcpy(vclock_index, ptp->vclock_index, size);
 306
 307         kfree(ptp->vclock_index);
 308         ptp->vclock_index = vclock_index;
 309         ptp->max_vclocks = max;
 310
 311         mutex_unlock(&ptp->n_vclocks_mux);
 312
 313         return count;
 314 out:
 315         mutex_unlock(&ptp->n_vclocks_mux);
 316         return err;
 317 }
 318 static DEVICE_ATTR_RW(max_vclocks);
 319
 320 static struct attribute *ptp_attrs[] = {
 321         &dev_attr_clock_name.attr,
 322
 323         &dev_attr_max_adjustment.attr,
 324         &dev_attr_max_phase_adjustment.attr,
 325         &dev_attr_n_alarms.attr,
 326         &dev_attr_n_external_timestamps.attr,
 327         &dev_attr_n_periodic_outputs.attr,
 328         &dev_attr_n_programmable_pins.attr,
 329         &dev_attr_pps_available.attr,
 330
 331         &dev_attr_extts_enable.attr,
 332         &dev_attr_fifo.attr,
 333         &dev_attr_period.attr,
 334         &dev_attr_pps_enable.attr,
 335         &dev_attr_n_vclocks.attr,
 336         &dev_attr_max_vclocks.attr,
 337         NULL
 338 };
 339
 340 static umode_t ptp_is_attribute_visible(struct kobject *kobj,
 341                                         struct attribute *attr, int n)
 342 {
 343         struct device *dev = kobj_to_dev(kobj);
 344         struct ptp_clock *ptp = dev_get_drvdata(dev);
 345         struct ptp_clock_info *info = ptp->info;
 346         umode_t mode = attr->mode;
 347
 348         if (attr == &dev_attr_extts_enable.attr ||
 349             attr == &dev_attr_fifo.attr) {
 350                 if (!info->n_ext_ts)
 351                         mode = 0;
 352         } else if (attr == &dev_attr_period.attr) {
 353                 if (!info->n_per_out)
 354                         mode = 0;
 355         } else if (attr == &dev_attr_pps_enable.attr) {
 356                 if (!info->pps)
 357                         mode = 0;
 358         } else if (attr == &dev_attr_n_vclocks.attr ||
 359                    attr == &dev_attr_max_vclocks.attr) {
 360                 if (ptp->is_virtual_clock)
 361                         mode = 0;
 362         } else if (attr == &dev_attr_max_phase_adjustment.attr) {
 363                 if (!info->adjphase || !info->getmaxphase)
 364                         mode = 0;
 365         }
 366
 367         return mode;
 368 }
 369
 370 static const struct attribute_group ptp_group = {
 371         .is_visible     = ptp_is_attribute_visible,
 372         .attrs          = ptp_attrs,
 373 };
 374
 375 const struct attribute_group *ptp_groups[] = {
 376         &ptp_group,
 377         NULL
 378 };
 379
 380 static int ptp_pin_name2index(struct ptp_clock *ptp, const char *name)
 381 {
 382         int i;
 383         for (i = 0; i < ptp->info->n_pins; i++) {
 384                 if (!strcmp(ptp->info->pin_config[i].name, name))
 385                         return i;
 386         }
 387         return -1;
 388 }
 389
 390 static ssize_t ptp_pin_show(struct device *dev, struct device_attribute *attr,
 391                             char *page)
 392 {
 393         struct ptp_clock *ptp = dev_get_drvdata(dev);
 394         unsigned int func, chan;
 395         int index;
 396
 397         index = ptp_pin_name2index(ptp, attr->attr.name);
 398         if (index < 0)
 399                 return -EINVAL;
 400
 401         if (mutex_lock_interruptible(&ptp->pincfg_mux))
 402                 return -ERESTARTSYS;
 403
 404         func = ptp->info->pin_config[index].func;
 405         chan = ptp->info->pin_config[index].chan;
 406
 407         mutex_unlock(&ptp->pincfg_mux);
 408
 409         return sysfs_emit(page, "%u %u\n", func, chan);
 410 }
 411
 412 static ssize_t ptp_pin_store(struct device *dev, struct device_attribute *attr,
 413                              const char *buf, size_t count)
 414 {
 415         struct ptp_clock *ptp = dev_get_drvdata(dev);
 416         unsigned int func, chan;
 417         int cnt, err, index;
 418
 419         cnt = sscanf(buf, "%u %u", &func, &chan);
 420         if (cnt != 2)
 421                 return -EINVAL;
 422
 423         index = ptp_pin_name2index(ptp, attr->attr.name);
 424         if (index < 0)
 425                 return -EINVAL;
 426
 427         if (mutex_lock_interruptible(&ptp->pincfg_mux))
 428                 return -ERESTARTSYS;
 429         err = ptp_set_pinfunc(ptp, index, func, chan);
 430         mutex_unlock(&ptp->pincfg_mux);
 431         if (err)
 432                 return err;
 433
 434         return count;
 435 }
 436
 437 int ptp_populate_pin_groups(struct ptp_clock *ptp)
 438 {
 439         struct ptp_clock_info *info = ptp->info;
 440         int err = -ENOMEM, i, n_pins = info->n_pins;
 441
 442         if (!n_pins)
 443                 return 0;
 444
 445         ptp->pin_dev_attr = kcalloc(n_pins, sizeof(*ptp->pin_dev_attr),
 446                                     GFP_KERNEL);
 447         if (!ptp->pin_dev_attr)
 448                 goto no_dev_attr;
 449
 450         ptp->pin_attr = kcalloc(1 + n_pins, sizeof(*ptp->pin_attr), GFP_KERNEL);
 451         if (!ptp->pin_attr)
 452                 goto no_pin_attr;
 453
 454         for (i = 0; i < n_pins; i++) {
 455                 struct device_attribute *da = &ptp->pin_dev_attr[i];
 456                 sysfs_attr_init(&da->attr);
 457                 da->attr.name = info->pin_config[i].name;
 458                 da->attr.mode = 0644;
 459                 da->show = ptp_pin_show;
 460                 da->store = ptp_pin_store;
 461                 ptp->pin_attr[i] = &da->attr;
 462         }
 463
 464         ptp->pin_attr_group.name = "pins";
 465         ptp->pin_attr_group.attrs = ptp->pin_attr;
 466
 467         ptp->pin_attr_groups[0] = &ptp->pin_attr_group;
 468
 469         return 0;
 470
 471 no_pin_attr:
 472         kfree(ptp->pin_dev_attr);
 473 no_dev_attr:
 474         return err;
 475 }
 476
 477 void ptp_cleanup_pin_groups(struct ptp_clock *ptp)
 478 {
 479         kfree(ptp->pin_attr);
 480         kfree(ptp->pin_dev_attr);
 481 }