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