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