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