drivers/media/common/siano/smsdvb-debugfs.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 //
   3 // Copyright(c) 2013 Mauro Carvalho Chehab
   4
   5 #include "smscoreapi.h"
   6
   7 #include <linux/module.h>
   8 #include <linux/slab.h>
   9 #include <linux/init.h>
  10 #include <linux/debugfs.h>
  11 #include <linux/spinlock.h>
  12 #include <linux/usb.h>
  13
  14 #include <media/dmxdev.h>
  15 #include <media/dvbdev.h>
  16 #include <media/dvb_demux.h>
  17 #include <media/dvb_frontend.h>
  18
  19 #include "smsdvb.h"
  20
  21 static struct dentry *smsdvb_debugfs_usb_root;
  22
  23 struct smsdvb_debugfs {
  24         struct kref             refcount;
  25         spinlock_t              lock;
  26
  27         char                    stats_data[PAGE_SIZE];
  28         unsigned                stats_count;
  29         bool                    stats_was_read;
  30
  31         wait_queue_head_t       stats_queue;
  32 };
  33
  34 static void smsdvb_print_dvb_stats(struct smsdvb_debugfs *debug_data,
  35                             struct sms_stats *p)
  36 {
  37         int n = 0;
  38         char *buf;
  39
  40         spin_lock(&debug_data->lock);
  41         if (debug_data->stats_count) {
  42                 spin_unlock(&debug_data->lock);
  43                 return;
  44         }
  45
  46         buf = debug_data->stats_data;
  47
  48         n += snprintf(&buf[n], PAGE_SIZE - n,
  49                       "is_rf_locked = %d\n", p->is_rf_locked);
  50         n += snprintf(&buf[n], PAGE_SIZE - n,
  51                       "is_demod_locked = %d\n", p->is_demod_locked);
  52         n += snprintf(&buf[n], PAGE_SIZE - n,
  53                       "is_external_lna_on = %d\n", p->is_external_lna_on);
  54         n += snprintf(&buf[n], PAGE_SIZE - n,
  55                       "SNR = %d\n", p->SNR);
  56         n += snprintf(&buf[n], PAGE_SIZE - n,
  57                       "ber = %d\n", p->ber);
  58         n += snprintf(&buf[n], PAGE_SIZE - n,
  59                       "FIB_CRC = %d\n", p->FIB_CRC);
  60         n += snprintf(&buf[n], PAGE_SIZE - n,
  61                       "ts_per = %d\n", p->ts_per);
  62         n += snprintf(&buf[n], PAGE_SIZE - n,
  63                       "MFER = %d\n", p->MFER);
  64         n += snprintf(&buf[n], PAGE_SIZE - n,
  65                       "RSSI = %d\n", p->RSSI);
  66         n += snprintf(&buf[n], PAGE_SIZE - n,
  67                       "in_band_pwr = %d\n", p->in_band_pwr);
  68         n += snprintf(&buf[n], PAGE_SIZE - n,
  69                       "carrier_offset = %d\n", p->carrier_offset);
  70         n += snprintf(&buf[n], PAGE_SIZE - n,
  71                       "modem_state = %d\n", p->modem_state);
  72         n += snprintf(&buf[n], PAGE_SIZE - n,
  73                       "frequency = %d\n", p->frequency);
  74         n += snprintf(&buf[n], PAGE_SIZE - n,
  75                       "bandwidth = %d\n", p->bandwidth);
  76         n += snprintf(&buf[n], PAGE_SIZE - n,
  77                       "transmission_mode = %d\n", p->transmission_mode);
  78         n += snprintf(&buf[n], PAGE_SIZE - n,
  79                       "modem_state = %d\n", p->modem_state);
  80         n += snprintf(&buf[n], PAGE_SIZE - n,
  81                       "guard_interval = %d\n", p->guard_interval);
  82         n += snprintf(&buf[n], PAGE_SIZE - n,
  83                       "code_rate = %d\n", p->code_rate);
  84         n += snprintf(&buf[n], PAGE_SIZE - n,
  85                       "lp_code_rate = %d\n", p->lp_code_rate);
  86         n += snprintf(&buf[n], PAGE_SIZE - n,
  87                       "hierarchy = %d\n", p->hierarchy);
  88         n += snprintf(&buf[n], PAGE_SIZE - n,
  89                       "constellation = %d\n", p->constellation);
  90         n += snprintf(&buf[n], PAGE_SIZE - n,
  91                       "burst_size = %d\n", p->burst_size);
  92         n += snprintf(&buf[n], PAGE_SIZE - n,
  93                       "burst_duration = %d\n", p->burst_duration);
  94         n += snprintf(&buf[n], PAGE_SIZE - n,
  95                       "burst_cycle_time = %d\n", p->burst_cycle_time);
  96         n += snprintf(&buf[n], PAGE_SIZE - n,
  97                       "calc_burst_cycle_time = %d\n",
  98                       p->calc_burst_cycle_time);
  99         n += snprintf(&buf[n], PAGE_SIZE - n,
 100                       "num_of_rows = %d\n", p->num_of_rows);
 101         n += snprintf(&buf[n], PAGE_SIZE - n,
 102                       "num_of_padd_cols = %d\n", p->num_of_padd_cols);
 103         n += snprintf(&buf[n], PAGE_SIZE - n,
 104                       "num_of_punct_cols = %d\n", p->num_of_punct_cols);
 105         n += snprintf(&buf[n], PAGE_SIZE - n,
 106                       "error_ts_packets = %d\n", p->error_ts_packets);
 107         n += snprintf(&buf[n], PAGE_SIZE - n,
 108                       "total_ts_packets = %d\n", p->total_ts_packets);
 109         n += snprintf(&buf[n], PAGE_SIZE - n,
 110                       "num_of_valid_mpe_tlbs = %d\n", p->num_of_valid_mpe_tlbs);
 111         n += snprintf(&buf[n], PAGE_SIZE - n,
 112                       "num_of_invalid_mpe_tlbs = %d\n", p->num_of_invalid_mpe_tlbs);
 113         n += snprintf(&buf[n], PAGE_SIZE - n,
 114                       "num_of_corrected_mpe_tlbs = %d\n", p->num_of_corrected_mpe_tlbs);
 115         n += snprintf(&buf[n], PAGE_SIZE - n,
 116                       "ber_error_count = %d\n", p->ber_error_count);
 117         n += snprintf(&buf[n], PAGE_SIZE - n,
 118                       "ber_bit_count = %d\n", p->ber_bit_count);
 119         n += snprintf(&buf[n], PAGE_SIZE - n,
 120                       "sms_to_host_tx_errors = %d\n", p->sms_to_host_tx_errors);
 121         n += snprintf(&buf[n], PAGE_SIZE - n,
 122                       "pre_ber = %d\n", p->pre_ber);
 123         n += snprintf(&buf[n], PAGE_SIZE - n,
 124                       "cell_id = %d\n", p->cell_id);
 125         n += snprintf(&buf[n], PAGE_SIZE - n,
 126                       "dvbh_srv_ind_hp = %d\n", p->dvbh_srv_ind_hp);
 127         n += snprintf(&buf[n], PAGE_SIZE - n,
 128                       "dvbh_srv_ind_lp = %d\n", p->dvbh_srv_ind_lp);
 129         n += snprintf(&buf[n], PAGE_SIZE - n,
 130                       "num_mpe_received = %d\n", p->num_mpe_received);
 131
 132         debug_data->stats_count = n;
 133         spin_unlock(&debug_data->lock);
 134         wake_up(&debug_data->stats_queue);
 135 }
 136
 137 static void smsdvb_print_isdb_stats(struct smsdvb_debugfs *debug_data,
 138                              struct sms_isdbt_stats *p)
 139 {
 140         int i, n = 0;
 141         char *buf;
 142
 143         spin_lock(&debug_data->lock);
 144         if (debug_data->stats_count) {
 145                 spin_unlock(&debug_data->lock);
 146                 return;
 147         }
 148
 149         buf = debug_data->stats_data;
 150
 151         n += snprintf(&buf[n], PAGE_SIZE - n,
 152                       "statistics_type = %d\t", p->statistics_type);
 153         n += snprintf(&buf[n], PAGE_SIZE - n,
 154                       "full_size = %d\n", p->full_size);
 155
 156         n += snprintf(&buf[n], PAGE_SIZE - n,
 157                       "is_rf_locked = %d\t\t", p->is_rf_locked);
 158         n += snprintf(&buf[n], PAGE_SIZE - n,
 159                       "is_demod_locked = %d\t", p->is_demod_locked);
 160         n += snprintf(&buf[n], PAGE_SIZE - n,
 161                       "is_external_lna_on = %d\n", p->is_external_lna_on);
 162         n += snprintf(&buf[n], PAGE_SIZE - n,
 163                       "SNR = %d dB\t\t", p->SNR);
 164         n += snprintf(&buf[n], PAGE_SIZE - n,
 165                       "RSSI = %d dBm\t\t", p->RSSI);
 166         n += snprintf(&buf[n], PAGE_SIZE - n,
 167                       "in_band_pwr = %d dBm\n", p->in_band_pwr);
 168         n += snprintf(&buf[n], PAGE_SIZE - n,
 169                       "carrier_offset = %d\t", p->carrier_offset);
 170         n += snprintf(&buf[n], PAGE_SIZE - n,
 171                       "bandwidth = %d\t\t", p->bandwidth);
 172         n += snprintf(&buf[n], PAGE_SIZE - n,
 173                       "frequency = %d Hz\n", p->frequency);
 174         n += snprintf(&buf[n], PAGE_SIZE - n,
 175                       "transmission_mode = %d\t", p->transmission_mode);
 176         n += snprintf(&buf[n], PAGE_SIZE - n,
 177                       "modem_state = %d\t\t", p->modem_state);
 178         n += snprintf(&buf[n], PAGE_SIZE - n,
 179                       "guard_interval = %d\n", p->guard_interval);
 180         n += snprintf(&buf[n], PAGE_SIZE - n,
 181                       "system_type = %d\t\t", p->system_type);
 182         n += snprintf(&buf[n], PAGE_SIZE - n,
 183                       "partial_reception = %d\t", p->partial_reception);
 184         n += snprintf(&buf[n], PAGE_SIZE - n,
 185                       "num_of_layers = %d\n", p->num_of_layers);
 186         n += snprintf(&buf[n], PAGE_SIZE - n,
 187                       "sms_to_host_tx_errors = %d\n", p->sms_to_host_tx_errors);
 188
 189         for (i = 0; i < 3; i++) {
 190                 if (p->layer_info[i].number_of_segments < 1 ||
 191                     p->layer_info[i].number_of_segments > 13)
 192                         continue;
 193
 194                 n += snprintf(&buf[n], PAGE_SIZE - n, "\nLayer %d\n", i);
 195                 n += snprintf(&buf[n], PAGE_SIZE - n, "\tcode_rate = %d\t",
 196                               p->layer_info[i].code_rate);
 197                 n += snprintf(&buf[n], PAGE_SIZE - n, "constellation = %d\n",
 198                               p->layer_info[i].constellation);
 199                 n += snprintf(&buf[n], PAGE_SIZE - n, "\tber = %-5d\t",
 200                               p->layer_info[i].ber);
 201                 n += snprintf(&buf[n], PAGE_SIZE - n, "\tber_error_count = %-5d\t",
 202                               p->layer_info[i].ber_error_count);
 203                 n += snprintf(&buf[n], PAGE_SIZE - n, "ber_bit_count = %-5d\n",
 204                               p->layer_info[i].ber_bit_count);
 205                 n += snprintf(&buf[n], PAGE_SIZE - n, "\tpre_ber = %-5d\t",
 206                               p->layer_info[i].pre_ber);
 207                 n += snprintf(&buf[n], PAGE_SIZE - n, "\tts_per = %-5d\n",
 208                               p->layer_info[i].ts_per);
 209                 n += snprintf(&buf[n], PAGE_SIZE - n, "\terror_ts_packets = %-5d\t",
 210                               p->layer_info[i].error_ts_packets);
 211                 n += snprintf(&buf[n], PAGE_SIZE - n, "total_ts_packets = %-5d\t",
 212                               p->layer_info[i].total_ts_packets);
 213                 n += snprintf(&buf[n], PAGE_SIZE - n, "ti_ldepth_i = %d\n",
 214                               p->layer_info[i].ti_ldepth_i);
 215                 n += snprintf(&buf[n], PAGE_SIZE - n,
 216                               "\tnumber_of_segments = %d\t",
 217                               p->layer_info[i].number_of_segments);
 218                 n += snprintf(&buf[n], PAGE_SIZE - n, "tmcc_errors = %d\n",
 219                               p->layer_info[i].tmcc_errors);
 220         }
 221
 222         debug_data->stats_count = n;
 223         spin_unlock(&debug_data->lock);
 224         wake_up(&debug_data->stats_queue);
 225 }
 226
 227 static void smsdvb_print_isdb_stats_ex(struct smsdvb_debugfs *debug_data,
 228                                 struct sms_isdbt_stats_ex *p)
 229 {
 230         int i, n = 0;
 231         char *buf;
 232
 233         spin_lock(&debug_data->lock);
 234         if (debug_data->stats_count) {
 235                 spin_unlock(&debug_data->lock);
 236                 return;
 237         }
 238
 239         buf = debug_data->stats_data;
 240
 241         n += snprintf(&buf[n], PAGE_SIZE - n,
 242                       "statistics_type = %d\t", p->statistics_type);
 243         n += snprintf(&buf[n], PAGE_SIZE - n,
 244                       "full_size = %d\n", p->full_size);
 245
 246         n += snprintf(&buf[n], PAGE_SIZE - n,
 247                       "is_rf_locked = %d\t\t", p->is_rf_locked);
 248         n += snprintf(&buf[n], PAGE_SIZE - n,
 249                       "is_demod_locked = %d\t", p->is_demod_locked);
 250         n += snprintf(&buf[n], PAGE_SIZE - n,
 251                       "is_external_lna_on = %d\n", p->is_external_lna_on);
 252         n += snprintf(&buf[n], PAGE_SIZE - n,
 253                       "SNR = %d dB\t\t", p->SNR);
 254         n += snprintf(&buf[n], PAGE_SIZE - n,
 255                       "RSSI = %d dBm\t\t", p->RSSI);
 256         n += snprintf(&buf[n], PAGE_SIZE - n,
 257                       "in_band_pwr = %d dBm\n", p->in_band_pwr);
 258         n += snprintf(&buf[n], PAGE_SIZE - n,
 259                       "carrier_offset = %d\t", p->carrier_offset);
 260         n += snprintf(&buf[n], PAGE_SIZE - n,
 261                       "bandwidth = %d\t\t", p->bandwidth);
 262         n += snprintf(&buf[n], PAGE_SIZE - n,
 263                       "frequency = %d Hz\n", p->frequency);
 264         n += snprintf(&buf[n], PAGE_SIZE - n,
 265                       "transmission_mode = %d\t", p->transmission_mode);
 266         n += snprintf(&buf[n], PAGE_SIZE - n,
 267                       "modem_state = %d\t\t", p->modem_state);
 268         n += snprintf(&buf[n], PAGE_SIZE - n,
 269                       "guard_interval = %d\n", p->guard_interval);
 270         n += snprintf(&buf[n], PAGE_SIZE - n,
 271                       "system_type = %d\t\t", p->system_type);
 272         n += snprintf(&buf[n], PAGE_SIZE - n,
 273                       "partial_reception = %d\t", p->partial_reception);
 274         n += snprintf(&buf[n], PAGE_SIZE - n,
 275                       "num_of_layers = %d\n", p->num_of_layers);
 276         n += snprintf(&buf[n], PAGE_SIZE - n, "segment_number = %d\t",
 277                       p->segment_number);
 278         n += snprintf(&buf[n], PAGE_SIZE - n, "tune_bw = %d\n",
 279                       p->tune_bw);
 280
 281         for (i = 0; i < 3; i++) {
 282                 if (p->layer_info[i].number_of_segments < 1 ||
 283                     p->layer_info[i].number_of_segments > 13)
 284                         continue;
 285
 286                 n += snprintf(&buf[n], PAGE_SIZE - n, "\nLayer %d\n", i);
 287                 n += snprintf(&buf[n], PAGE_SIZE - n, "\tcode_rate = %d\t",
 288                               p->layer_info[i].code_rate);
 289                 n += snprintf(&buf[n], PAGE_SIZE - n, "constellation = %d\n",
 290                               p->layer_info[i].constellation);
 291                 n += snprintf(&buf[n], PAGE_SIZE - n, "\tber = %-5d\t",
 292                               p->layer_info[i].ber);
 293                 n += snprintf(&buf[n], PAGE_SIZE - n, "\tber_error_count = %-5d\t",
 294                               p->layer_info[i].ber_error_count);
 295                 n += snprintf(&buf[n], PAGE_SIZE - n, "ber_bit_count = %-5d\n",
 296                               p->layer_info[i].ber_bit_count);
 297                 n += snprintf(&buf[n], PAGE_SIZE - n, "\tpre_ber = %-5d\t",
 298                               p->layer_info[i].pre_ber);
 299                 n += snprintf(&buf[n], PAGE_SIZE - n, "\tts_per = %-5d\n",
 300                               p->layer_info[i].ts_per);
 301                 n += snprintf(&buf[n], PAGE_SIZE - n, "\terror_ts_packets = %-5d\t",
 302                               p->layer_info[i].error_ts_packets);
 303                 n += snprintf(&buf[n], PAGE_SIZE - n, "total_ts_packets = %-5d\t",
 304                               p->layer_info[i].total_ts_packets);
 305                 n += snprintf(&buf[n], PAGE_SIZE - n, "ti_ldepth_i = %d\n",
 306                               p->layer_info[i].ti_ldepth_i);
 307                 n += snprintf(&buf[n], PAGE_SIZE - n,
 308                               "\tnumber_of_segments = %d\t",
 309                               p->layer_info[i].number_of_segments);
 310                 n += snprintf(&buf[n], PAGE_SIZE - n, "tmcc_errors = %d\n",
 311                               p->layer_info[i].tmcc_errors);
 312         }
 313
 314
 315         debug_data->stats_count = n;
 316         spin_unlock(&debug_data->lock);
 317
 318         wake_up(&debug_data->stats_queue);
 319 }
 320
 321 static int smsdvb_stats_open(struct inode *inode, struct file *file)
 322 {
 323         struct smsdvb_client_t *client = inode->i_private;
 324         struct smsdvb_debugfs *debug_data = client->debug_data;
 325
 326         kref_get(&debug_data->refcount);
 327
 328         spin_lock(&debug_data->lock);
 329         debug_data->stats_count = 0;
 330         debug_data->stats_was_read = false;
 331         spin_unlock(&debug_data->lock);
 332
 333         file->private_data = debug_data;
 334
 335         return 0;
 336 }
 337
 338 static void smsdvb_debugfs_data_release(struct kref *ref)
 339 {
 340         struct smsdvb_debugfs *debug_data;
 341
 342         debug_data = container_of(ref, struct smsdvb_debugfs, refcount);
 343         kfree(debug_data);
 344 }
 345
 346 static int smsdvb_stats_wait_read(struct smsdvb_debugfs *debug_data)
 347 {
 348         int rc = 1;
 349
 350         spin_lock(&debug_data->lock);
 351
 352         if (debug_data->stats_was_read)
 353                 goto exit;
 354
 355         rc = debug_data->stats_count;
 356
 357 exit:
 358         spin_unlock(&debug_data->lock);
 359         return rc;
 360 }
 361
 362 static __poll_t smsdvb_stats_poll(struct file *file, poll_table *wait)
 363 {
 364         struct smsdvb_debugfs *debug_data = file->private_data;
 365         int rc;
 366
 367         kref_get(&debug_data->refcount);
 368
 369         poll_wait(file, &debug_data->stats_queue, wait);
 370
 371         rc = smsdvb_stats_wait_read(debug_data);
 372         kref_put(&debug_data->refcount, smsdvb_debugfs_data_release);
 373
 374         return rc > 0 ? EPOLLIN | EPOLLRDNORM : 0;
 375 }
 376
 377 static ssize_t smsdvb_stats_read(struct file *file, char __user *user_buf,
 378                                       size_t nbytes, loff_t *ppos)
 379 {
 380         int rc = 0, len;
 381         struct smsdvb_debugfs *debug_data = file->private_data;
 382
 383         kref_get(&debug_data->refcount);
 384
 385         if (file->f_flags & O_NONBLOCK) {
 386                 rc = smsdvb_stats_wait_read(debug_data);
 387                 if (!rc) {
 388                         rc = -EWOULDBLOCK;
 389                         goto ret;
 390                 }
 391         } else {
 392                 rc = wait_event_interruptible(debug_data->stats_queue,
 393                                       smsdvb_stats_wait_read(debug_data));
 394                 if (rc < 0)
 395                         goto ret;
 396         }
 397
 398         if (debug_data->stats_was_read) {
 399                 rc = 0; /* EOF */
 400                 goto ret;
 401         }
 402
 403         len = debug_data->stats_count - *ppos;
 404         if (len >= 0)
 405                 rc = simple_read_from_buffer(user_buf, nbytes, ppos,
 406                                              debug_data->stats_data, len);
 407         else
 408                 rc = 0;
 409
 410         if (*ppos >= debug_data->stats_count) {
 411                 spin_lock(&debug_data->lock);
 412                 debug_data->stats_was_read = true;
 413                 spin_unlock(&debug_data->lock);
 414         }
 415 ret:
 416         kref_put(&debug_data->refcount, smsdvb_debugfs_data_release);
 417         return rc;
 418 }
 419
 420 static int smsdvb_stats_release(struct inode *inode, struct file *file)
 421 {
 422         struct smsdvb_debugfs *debug_data = file->private_data;
 423
 424         spin_lock(&debug_data->lock);
 425         debug_data->stats_was_read = true;      /* return EOF to read() */
 426         spin_unlock(&debug_data->lock);
 427         wake_up_interruptible_sync(&debug_data->stats_queue);
 428
 429         kref_put(&debug_data->refcount, smsdvb_debugfs_data_release);
 430         file->private_data = NULL;
 431
 432         return 0;
 433 }
 434
 435 static const struct file_operations debugfs_stats_ops = {
 436         .open = smsdvb_stats_open,
 437         .poll = smsdvb_stats_poll,
 438         .read = smsdvb_stats_read,
 439         .release = smsdvb_stats_release,
 440         .llseek = generic_file_llseek,
 441 };
 442
 443 /*
 444  * Functions used by smsdvb, in order to create the interfaces
 445  */
 446
 447 int smsdvb_debugfs_create(struct smsdvb_client_t *client)
 448 {
 449         struct smscore_device_t *coredev = client->coredev;
 450         struct dentry *d;
 451         struct smsdvb_debugfs *debug_data;
 452
 453         if (!smsdvb_debugfs_usb_root || !coredev->is_usb_device)
 454                 return -ENODEV;
 455
 456         client->debugfs = debugfs_create_dir(coredev->devpath,
 457                                              smsdvb_debugfs_usb_root);
 458         if (IS_ERR_OR_NULL(client->debugfs)) {
 459                 pr_info("Unable to create debugfs %s directory.\n",
 460                         coredev->devpath);
 461                 return -ENODEV;
 462         }
 463
 464         d = debugfs_create_file("stats", S_IRUGO | S_IWUSR, client->debugfs,
 465                                 client, &debugfs_stats_ops);
 466         if (!d) {
 467                 debugfs_remove(client->debugfs);
 468                 return -ENOMEM;
 469         }
 470
 471         debug_data = kzalloc(sizeof(*client->debug_data), GFP_KERNEL);
 472         if (!debug_data)
 473                 return -ENOMEM;
 474
 475         client->debug_data        = debug_data;
 476         client->prt_dvb_stats     = smsdvb_print_dvb_stats;
 477         client->prt_isdb_stats    = smsdvb_print_isdb_stats;
 478         client->prt_isdb_stats_ex = smsdvb_print_isdb_stats_ex;
 479
 480         init_waitqueue_head(&debug_data->stats_queue);
 481         spin_lock_init(&debug_data->lock);
 482         kref_init(&debug_data->refcount);
 483
 484         return 0;
 485 }
 486
 487 void smsdvb_debugfs_release(struct smsdvb_client_t *client)
 488 {
 489         if (!client->debugfs)
 490                 return;
 491
 492         client->prt_dvb_stats     = NULL;
 493         client->prt_isdb_stats    = NULL;
 494         client->prt_isdb_stats_ex = NULL;
 495
 496         debugfs_remove_recursive(client->debugfs);
 497         kref_put(&client->debug_data->refcount, smsdvb_debugfs_data_release);
 498
 499         client->debug_data = NULL;
 500         client->debugfs = NULL;
 501 }
 502
 503 void smsdvb_debugfs_register(void)
 504 {
 505         struct dentry *d;
 506
 507         /*
 508          * FIXME: This was written to debug Siano USB devices. So, it creates
 509          * the debugfs node under <debugfs>/usb.
 510          * A similar logic would be needed for Siano sdio devices, but, in that
 511          * case, usb_debug_root is not a good choice.
 512          *
 513          * Perhaps the right fix here would be to create another sysfs root
 514          * node for sdio-based boards, but this may need some logic at sdio
 515          * subsystem.
 516          */
 517         d = debugfs_create_dir("smsdvb", usb_debug_root);
 518         if (IS_ERR_OR_NULL(d)) {
 519                 pr_err("Couldn't create sysfs node for smsdvb\n");
 520                 return;
 521         }
 522         smsdvb_debugfs_usb_root = d;
 523 }
 524
 525 void smsdvb_debugfs_unregister(void)
 526 {
 527         if (!smsdvb_debugfs_usb_root)
 528                 return;
 529         debugfs_remove_recursive(smsdvb_debugfs_usb_root);
 530         smsdvb_debugfs_usb_root = NULL;
 531 }