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 snprintf(page, PAGE_SIZE-1, "%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         u8 *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, "%d\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                         dev_info(dev, "new virtual clock ptp%d\n",
 217                                  vclock->clock->index);
 218                 }
 219         }
 220
 221         /* Need to delete vclocks */
 222         if (num < ptp->n_vclocks) {
 223                 i = ptp->n_vclocks - num;
 224                 device_for_each_child_reverse(dev, &i,
 225                                               unregister_vclock);
 226         }
 227
 228         if (num == 0)
 229                 dev_info(dev, "only physical clock in use now\n");
 230         else
 231                 dev_info(dev, "guarantee physical clock free running\n");
 232
 233         ptp->n_vclocks = num;
 234         mutex_unlock(&ptp->n_vclocks_mux);
 235
 236         return count;
 237 out:
 238         mutex_unlock(&ptp->n_vclocks_mux);
 239         return err;
 240 }
 241 static DEVICE_ATTR_RW(n_vclocks);
 242
 243 static ssize_t max_vclocks_show(struct device *dev,
 244                                 struct device_attribute *attr, char *page)
 245 {
 246         struct ptp_clock *ptp = dev_get_drvdata(dev);
 247         ssize_t size;
 248
 249         size = snprintf(page, PAGE_SIZE - 1, "%d\n", ptp->max_vclocks);
 250
 251         return size;
 252 }
 253
 254 static ssize_t max_vclocks_store(struct device *dev,
 255                                  struct device_attribute *attr,
 256                                  const char *buf, size_t count)
 257 {
 258         struct ptp_clock *ptp = dev_get_drvdata(dev);
 259         u32 max;
 260
 261         if (kstrtou32(buf, 0, &max) || max == 0)
 262                 return -EINVAL;
 263
 264         if (max == ptp->max_vclocks)
 265                 return count;
 266
 267         if (mutex_lock_interruptible(&ptp->n_vclocks_mux))
 268                 return -ERESTARTSYS;
 269
 270         if (max < ptp->n_vclocks) {
 271                 mutex_unlock(&ptp->n_vclocks_mux);
 272                 return -EINVAL;
 273         }
 274
 275         ptp->max_vclocks = max;
 276
 277         mutex_unlock(&ptp->n_vclocks_mux);
 278
 279         return count;
 280 }
 281 static DEVICE_ATTR_RW(max_vclocks);
 282
 283 static struct attribute *ptp_attrs[] = {
 284         &dev_attr_clock_name.attr,
 285
 286         &dev_attr_max_adjustment.attr,
 287         &dev_attr_n_alarms.attr,
 288         &dev_attr_n_external_timestamps.attr,
 289         &dev_attr_n_periodic_outputs.attr,
 290         &dev_attr_n_programmable_pins.attr,
 291         &dev_attr_pps_available.attr,
 292
 293         &dev_attr_extts_enable.attr,
 294         &dev_attr_fifo.attr,
 295         &dev_attr_period.attr,
 296         &dev_attr_pps_enable.attr,
 297         &dev_attr_n_vclocks.attr,
 298         &dev_attr_max_vclocks.attr,
 299         NULL
 300 };
 301
 302 static umode_t ptp_is_attribute_visible(struct kobject *kobj,
 303                                         struct attribute *attr, int n)
 304 {
 305         struct device *dev = kobj_to_dev(kobj);
 306         struct ptp_clock *ptp = dev_get_drvdata(dev);
 307         struct ptp_clock_info *info = ptp->info;
 308         umode_t mode = attr->mode;
 309
 310         if (attr == &dev_attr_extts_enable.attr ||
 311             attr == &dev_attr_fifo.attr) {
 312                 if (!info->n_ext_ts)
 313                         mode = 0;
 314         } else if (attr == &dev_attr_period.attr) {
 315                 if (!info->n_per_out)
 316                         mode = 0;
 317         } else if (attr == &dev_attr_pps_enable.attr) {
 318                 if (!info->pps)
 319                         mode = 0;
 320         } else if (attr == &dev_attr_n_vclocks.attr ||
 321                    attr == &dev_attr_max_vclocks.attr) {
 322                 if (ptp->is_virtual_clock)
 323                         mode = 0;
 324         }
 325
 326         return mode;
 327 }
 328
 329 static const struct attribute_group ptp_group = {
 330         .is_visible     = ptp_is_attribute_visible,
 331         .attrs          = ptp_attrs,
 332 };
 333
 334 const struct attribute_group *ptp_groups[] = {
 335         &ptp_group,
 336         NULL
 337 };
 338
 339 static int ptp_pin_name2index(struct ptp_clock *ptp, const char *name)
 340 {
 341         int i;
 342         for (i = 0; i < ptp->info->n_pins; i++) {
 343                 if (!strcmp(ptp->info->pin_config[i].name, name))
 344                         return i;
 345         }
 346         return -1;
 347 }
 348
 349 static ssize_t ptp_pin_show(struct device *dev, struct device_attribute *attr,
 350                             char *page)
 351 {
 352         struct ptp_clock *ptp = dev_get_drvdata(dev);
 353         unsigned int func, chan;
 354         int index;
 355
 356         index = ptp_pin_name2index(ptp, attr->attr.name);
 357         if (index < 0)
 358                 return -EINVAL;
 359
 360         if (mutex_lock_interruptible(&ptp->pincfg_mux))
 361                 return -ERESTARTSYS;
 362
 363         func = ptp->info->pin_config[index].func;
 364         chan = ptp->info->pin_config[index].chan;
 365
 366         mutex_unlock(&ptp->pincfg_mux);
 367
 368         return snprintf(page, PAGE_SIZE, "%u %u\n", func, chan);
 369 }
 370
 371 static ssize_t ptp_pin_store(struct device *dev, struct device_attribute *attr,
 372                              const char *buf, size_t count)
 373 {
 374         struct ptp_clock *ptp = dev_get_drvdata(dev);
 375         unsigned int func, chan;
 376         int cnt, err, index;
 377
 378         cnt = sscanf(buf, "%u %u", &func, &chan);
 379         if (cnt != 2)
 380                 return -EINVAL;
 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         err = ptp_set_pinfunc(ptp, index, func, chan);
 389         mutex_unlock(&ptp->pincfg_mux);
 390         if (err)
 391                 return err;
 392
 393         return count;
 394 }
 395
 396 int ptp_populate_pin_groups(struct ptp_clock *ptp)
 397 {
 398         struct ptp_clock_info *info = ptp->info;
 399         int err = -ENOMEM, i, n_pins = info->n_pins;
 400
 401         if (!n_pins)
 402                 return 0;
 403
 404         ptp->pin_dev_attr = kcalloc(n_pins, sizeof(*ptp->pin_dev_attr),
 405                                     GFP_KERNEL);
 406         if (!ptp->pin_dev_attr)
 407                 goto no_dev_attr;
 408
 409         ptp->pin_attr = kcalloc(1 + n_pins, sizeof(*ptp->pin_attr), GFP_KERNEL);
 410         if (!ptp->pin_attr)
 411                 goto no_pin_attr;
 412
 413         for (i = 0; i < n_pins; i++) {
 414                 struct device_attribute *da = &ptp->pin_dev_attr[i];
 415                 sysfs_attr_init(&da->attr);
 416                 da->attr.name = info->pin_config[i].name;
 417                 da->attr.mode = 0644;
 418                 da->show = ptp_pin_show;
 419                 da->store = ptp_pin_store;
 420                 ptp->pin_attr[i] = &da->attr;
 421         }
 422
 423         ptp->pin_attr_group.name = "pins";
 424         ptp->pin_attr_group.attrs = ptp->pin_attr;
 425
 426         ptp->pin_attr_groups[0] = &ptp->pin_attr_group;
 427
 428         return 0;
 429
 430 no_pin_attr:
 431         kfree(ptp->pin_dev_attr);
 432 no_dev_attr:
 433         return err;
 434 }
 435
 436 void ptp_cleanup_pin_groups(struct ptp_clock *ptp)
 437 {
 438         kfree(ptp->pin_attr);
 439         kfree(ptp->pin_dev_attr);
 440 }