drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.c

   1 /**
   2  * Copyright (c) 2014 Raspberry Pi (Trading) Ltd. All rights reserved.
   3  * Copyright (c) 2010-2012 Broadcom. All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions, and the following disclaimer,
  10  *    without modification.
  11  * 2. Redistributions in binary form must reproduce the above copyright
  12  *    notice, this list of conditions and the following disclaimer in the
  13  *    documentation and/or other materials provided with the distribution.
  14  * 3. The names of the above-listed copyright holders may not be used
  15  *    to endorse or promote products derived from this software without
  16  *    specific prior written permission.
  17  *
  18  * ALTERNATIVELY, this software may be distributed under the terms of the
  19  * GNU General Public License ("GPL") version 2, as published by the Free
  20  * Software Foundation.
  21  *
  22  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
  23  * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
  24  * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  25  * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
  26  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  27  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  28  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
  29  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
  30  * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
  31  * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
  32  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  33  */
  34
  35 #include <linux/kernel.h>
  36 #include <linux/module.h>
  37 #include <linux/types.h>
  38 #include <linux/errno.h>
  39 #include <linux/cdev.h>
  40 #include <linux/fs.h>
  41 #include <linux/device.h>
  42 #include <linux/mm.h>
  43 #include <linux/highmem.h>
  44 #include <linux/pagemap.h>
  45 #include <linux/bug.h>
  46 #include <linux/semaphore.h>
  47 #include <linux/list.h>
  48 #include <linux/of.h>
  49 #include <linux/platform_device.h>
  50 #include <soc/bcm2835/raspberrypi-firmware.h>
  51
  52 #include "vchiq_core.h"
  53 #include "vchiq_ioctl.h"
  54 #include "vchiq_arm.h"
  55 #include "vchiq_debugfs.h"
  56 #include "vchiq_killable.h"
  57
  58 #define DEVICE_NAME "vchiq"
  59
  60 /* Override the default prefix, which would be vchiq_arm (from the filename) */
  61 #undef MODULE_PARAM_PREFIX
  62 #define MODULE_PARAM_PREFIX DEVICE_NAME "."
  63
  64 #define VCHIQ_MINOR 0
  65
  66 /* Some per-instance constants */
  67 #define MAX_COMPLETIONS 16
  68 #define MAX_SERVICES 64
  69 #define MAX_ELEMENTS 8
  70 #define MSG_QUEUE_SIZE 64
  71
  72 #define KEEPALIVE_VER 1
  73 #define KEEPALIVE_VER_MIN KEEPALIVE_VER
  74
  75 /* Run time control of log level, based on KERN_XXX level. */
  76 int vchiq_arm_log_level = VCHIQ_LOG_DEFAULT;
  77 int vchiq_susp_log_level = VCHIQ_LOG_ERROR;
  78
  79 #define SUSPEND_TIMER_TIMEOUT_MS 100
  80 #define SUSPEND_RETRY_TIMER_TIMEOUT_MS 1000
  81
  82 #define VC_SUSPEND_NUM_OFFSET 3 /* number of values before idle which are -ve */
  83 static const char *const suspend_state_names[] = {
  84         "VC_SUSPEND_FORCE_CANCELED",
  85         "VC_SUSPEND_REJECTED",
  86         "VC_SUSPEND_FAILED",
  87         "VC_SUSPEND_IDLE",
  88         "VC_SUSPEND_REQUESTED",
  89         "VC_SUSPEND_IN_PROGRESS",
  90         "VC_SUSPEND_SUSPENDED"
  91 };
  92 #define VC_RESUME_NUM_OFFSET 1 /* number of values before idle which are -ve */
  93 static const char *const resume_state_names[] = {
  94         "VC_RESUME_FAILED",
  95         "VC_RESUME_IDLE",
  96         "VC_RESUME_REQUESTED",
  97         "VC_RESUME_IN_PROGRESS",
  98         "VC_RESUME_RESUMED"
  99 };
 100 /* The number of times we allow force suspend to timeout before actually
 101 ** _forcing_ suspend.  This is to cater for SW which fails to release vchiq
 102 ** correctly - we don't want to prevent ARM suspend indefinitely in this case.
 103 */
 104 #define FORCE_SUSPEND_FAIL_MAX 8
 105
 106 /* The time in ms allowed for videocore to go idle when force suspend has been
 107  * requested */
 108 #define FORCE_SUSPEND_TIMEOUT_MS 200
 109
 110
 111 static void suspend_timer_callback(unsigned long context);
 112
 113
 114 typedef struct user_service_struct {
 115         VCHIQ_SERVICE_T *service;
 116         void *userdata;
 117         VCHIQ_INSTANCE_T instance;
 118         char is_vchi;
 119         char dequeue_pending;
 120         char close_pending;
 121         int message_available_pos;
 122         int msg_insert;
 123         int msg_remove;
 124         struct semaphore insert_event;
 125         struct semaphore remove_event;
 126         struct semaphore close_event;
 127         VCHIQ_HEADER_T * msg_queue[MSG_QUEUE_SIZE];
 128 } USER_SERVICE_T;
 129
 130 struct bulk_waiter_node {
 131         struct bulk_waiter bulk_waiter;
 132         int pid;
 133         struct list_head list;
 134 };
 135
 136 struct vchiq_instance_struct {
 137         VCHIQ_STATE_T *state;
 138         VCHIQ_COMPLETION_DATA_T completions[MAX_COMPLETIONS];
 139         int completion_insert;
 140         int completion_remove;
 141         struct semaphore insert_event;
 142         struct semaphore remove_event;
 143         struct mutex completion_mutex;
 144
 145         int connected;
 146         int closing;
 147         int pid;
 148         int mark;
 149         int use_close_delivered;
 150         int trace;
 151
 152         struct list_head bulk_waiter_list;
 153         struct mutex bulk_waiter_list_mutex;
 154
 155         VCHIQ_DEBUGFS_NODE_T debugfs_node;
 156 };
 157
 158 typedef struct dump_context_struct {
 159         char __user *buf;
 160         size_t actual;
 161         size_t space;
 162         loff_t offset;
 163 } DUMP_CONTEXT_T;
 164
 165 static struct cdev    vchiq_cdev;
 166 static dev_t          vchiq_devid;
 167 static VCHIQ_STATE_T g_state;
 168 static struct class  *vchiq_class;
 169 static struct device *vchiq_dev;
 170 static DEFINE_SPINLOCK(msg_queue_spinlock);
 171
 172 static const char *const ioctl_names[] = {
 173         "CONNECT",
 174         "SHUTDOWN",
 175         "CREATE_SERVICE",
 176         "REMOVE_SERVICE",
 177         "QUEUE_MESSAGE",
 178         "QUEUE_BULK_TRANSMIT",
 179         "QUEUE_BULK_RECEIVE",
 180         "AWAIT_COMPLETION",
 181         "DEQUEUE_MESSAGE",
 182         "GET_CLIENT_ID",
 183         "GET_CONFIG",
 184         "CLOSE_SERVICE",
 185         "USE_SERVICE",
 186         "RELEASE_SERVICE",
 187         "SET_SERVICE_OPTION",
 188         "DUMP_PHYS_MEM",
 189         "LIB_VERSION",
 190         "CLOSE_DELIVERED"
 191 };
 192
 193 vchiq_static_assert((sizeof(ioctl_names)/sizeof(ioctl_names[0])) ==
 194         (VCHIQ_IOC_MAX + 1));
 195
 196 static void
 197 dump_phys_mem(void *virt_addr, uint32_t num_bytes);
 198
 199 /****************************************************************************
 200 *
 201 *   add_completion
 202 *
 203 ***************************************************************************/
 204
 205 static VCHIQ_STATUS_T
 206 add_completion(VCHIQ_INSTANCE_T instance, VCHIQ_REASON_T reason,
 207         VCHIQ_HEADER_T *header, USER_SERVICE_T *user_service,
 208         void *bulk_userdata)
 209 {
 210         VCHIQ_COMPLETION_DATA_T *completion;
 211         DEBUG_INITIALISE(g_state.local)
 212
 213         while (instance->completion_insert ==
 214                 (instance->completion_remove + MAX_COMPLETIONS)) {
 215                 /* Out of space - wait for the client */
 216                 DEBUG_TRACE(SERVICE_CALLBACK_LINE);
 217                 vchiq_log_trace(vchiq_arm_log_level,
 218                         "add_completion - completion queue full");
 219                 DEBUG_COUNT(COMPLETION_QUEUE_FULL_COUNT);
 220                 if (down_interruptible(&instance->remove_event) != 0) {
 221                         vchiq_log_info(vchiq_arm_log_level,
 222                                 "service_callback interrupted");
 223                         return VCHIQ_RETRY;
 224                 } else if (instance->closing) {
 225                         vchiq_log_info(vchiq_arm_log_level,
 226                                 "service_callback closing");
 227                         return VCHIQ_ERROR;
 228                 }
 229                 DEBUG_TRACE(SERVICE_CALLBACK_LINE);
 230         }
 231
 232         completion =
 233                  &instance->completions[instance->completion_insert &
 234                  (MAX_COMPLETIONS - 1)];
 235
 236         completion->header = header;
 237         completion->reason = reason;
 238         /* N.B. service_userdata is updated while processing AWAIT_COMPLETION */
 239         completion->service_userdata = user_service->service;
 240         completion->bulk_userdata = bulk_userdata;
 241
 242         if (reason == VCHIQ_SERVICE_CLOSED) {
 243                 /* Take an extra reference, to be held until
 244                    this CLOSED notification is delivered. */
 245                 lock_service(user_service->service);
 246                 if (instance->use_close_delivered)
 247                         user_service->close_pending = 1;
 248         }
 249
 250         /* A write barrier is needed here to ensure that the entire completion
 251                 record is written out before the insert point. */
 252         wmb();
 253
 254         if (reason == VCHIQ_MESSAGE_AVAILABLE)
 255                 user_service->message_available_pos =
 256                         instance->completion_insert;
 257         instance->completion_insert++;
 258
 259         up(&instance->insert_event);
 260
 261         return VCHIQ_SUCCESS;
 262 }
 263
 264 /****************************************************************************
 265 *
 266 *   service_callback
 267 *
 268 ***************************************************************************/
 269
 270 static VCHIQ_STATUS_T
 271 service_callback(VCHIQ_REASON_T reason, VCHIQ_HEADER_T *header,
 272         VCHIQ_SERVICE_HANDLE_T handle, void *bulk_userdata)
 273 {
 274         /* How do we ensure the callback goes to the right client?
 275         ** The service_user data points to a USER_SERVICE_T record containing
 276         ** the original callback and the user state structure, which contains a
 277         ** circular buffer for completion records.
 278         */
 279         USER_SERVICE_T *user_service;
 280         VCHIQ_SERVICE_T *service;
 281         VCHIQ_INSTANCE_T instance;
 282         DEBUG_INITIALISE(g_state.local)
 283
 284         DEBUG_TRACE(SERVICE_CALLBACK_LINE);
 285
 286         service = handle_to_service(handle);
 287         BUG_ON(!service);
 288         user_service = (USER_SERVICE_T *)service->base.userdata;
 289         instance = user_service->instance;
 290
 291         if (!instance || instance->closing)
 292                 return VCHIQ_SUCCESS;
 293
 294         vchiq_log_trace(vchiq_arm_log_level,
 295                 "service_callback - service %lx(%d,%p), reason %d, header %lx, "
 296                 "instance %lx, bulk_userdata %lx",
 297                 (unsigned long)user_service,
 298                 service->localport, user_service->userdata,
 299                 reason, (unsigned long)header,
 300                 (unsigned long)instance, (unsigned long)bulk_userdata);
 301
 302         if (header && user_service->is_vchi) {
 303                 spin_lock(&msg_queue_spinlock);
 304                 while (user_service->msg_insert ==
 305                         (user_service->msg_remove + MSG_QUEUE_SIZE)) {
 306                         spin_unlock(&msg_queue_spinlock);
 307                         DEBUG_TRACE(SERVICE_CALLBACK_LINE);
 308                         DEBUG_COUNT(MSG_QUEUE_FULL_COUNT);
 309                         vchiq_log_trace(vchiq_arm_log_level,
 310                                 "service_callback - msg queue full");
 311                         /* If there is no MESSAGE_AVAILABLE in the completion
 312                         ** queue, add one
 313                         */
 314                         if ((user_service->message_available_pos -
 315                                 instance->completion_remove) < 0) {
 316                                 VCHIQ_STATUS_T status;
 317                                 vchiq_log_info(vchiq_arm_log_level,
 318                                         "Inserting extra MESSAGE_AVAILABLE");
 319                                 DEBUG_TRACE(SERVICE_CALLBACK_LINE);
 320                                 status = add_completion(instance, reason,
 321                                         NULL, user_service, bulk_userdata);
 322                                 if (status != VCHIQ_SUCCESS) {
 323                                         DEBUG_TRACE(SERVICE_CALLBACK_LINE);
 324                                         return status;
 325                                 }
 326                         }
 327
 328                         DEBUG_TRACE(SERVICE_CALLBACK_LINE);
 329                         if (down_interruptible(&user_service->remove_event)
 330                                 != 0) {
 331                                 vchiq_log_info(vchiq_arm_log_level,
 332                                         "service_callback interrupted");
 333                                 DEBUG_TRACE(SERVICE_CALLBACK_LINE);
 334                                 return VCHIQ_RETRY;
 335                         } else if (instance->closing) {
 336                                 vchiq_log_info(vchiq_arm_log_level,
 337                                         "service_callback closing");
 338                                 DEBUG_TRACE(SERVICE_CALLBACK_LINE);
 339                                 return VCHIQ_ERROR;
 340                         }
 341                         DEBUG_TRACE(SERVICE_CALLBACK_LINE);
 342                         spin_lock(&msg_queue_spinlock);
 343                 }
 344
 345                 user_service->msg_queue[user_service->msg_insert &
 346                         (MSG_QUEUE_SIZE - 1)] = header;
 347                 user_service->msg_insert++;
 348                 spin_unlock(&msg_queue_spinlock);
 349
 350                 up(&user_service->insert_event);
 351
 352                 /* If there is a thread waiting in DEQUEUE_MESSAGE, or if
 353                 ** there is a MESSAGE_AVAILABLE in the completion queue then
 354                 ** bypass the completion queue.
 355                 */
 356                 if (((user_service->message_available_pos -
 357                         instance->completion_remove) >= 0) ||
 358                         user_service->dequeue_pending) {
 359                         DEBUG_TRACE(SERVICE_CALLBACK_LINE);
 360                         user_service->dequeue_pending = 0;
 361                         return VCHIQ_SUCCESS;
 362                 }
 363
 364                 header = NULL;
 365         }
 366         DEBUG_TRACE(SERVICE_CALLBACK_LINE);
 367
 368         return add_completion(instance, reason, header, user_service,
 369                 bulk_userdata);
 370 }
 371
 372 /****************************************************************************
 373 *
 374 *   user_service_free
 375 *
 376 ***************************************************************************/
 377 static void
 378 user_service_free(void *userdata)
 379 {
 380         kfree(userdata);
 381 }
 382
 383 /****************************************************************************
 384 *
 385 *   close_delivered
 386 *
 387 ***************************************************************************/
 388 static void close_delivered(USER_SERVICE_T *user_service)
 389 {
 390         vchiq_log_info(vchiq_arm_log_level,
 391                 "close_delivered(handle=%x)",
 392                 user_service->service->handle);
 393
 394         if (user_service->close_pending) {
 395                 /* Allow the underlying service to be culled */
 396                 unlock_service(user_service->service);
 397
 398                 /* Wake the user-thread blocked in close_ or remove_service */
 399                 up(&user_service->close_event);
 400
 401                 user_service->close_pending = 0;
 402         }
 403 }
 404
 405 /****************************************************************************
 406 *
 407 *   vchiq_ioctl
 408 *
 409 ***************************************************************************/
 410 static long
 411 vchiq_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 412 {
 413         VCHIQ_INSTANCE_T instance = file->private_data;
 414         VCHIQ_STATUS_T status = VCHIQ_SUCCESS;
 415         VCHIQ_SERVICE_T *service = NULL;
 416         long ret = 0;
 417         int i, rc;
 418         DEBUG_INITIALISE(g_state.local)
 419
 420         vchiq_log_trace(vchiq_arm_log_level,
 421                  "vchiq_ioctl - instance %x, cmd %s, arg %lx",
 422                 (unsigned int)instance,
 423                 ((_IOC_TYPE(cmd) == VCHIQ_IOC_MAGIC) &&
 424                 (_IOC_NR(cmd) <= VCHIQ_IOC_MAX)) ?
 425                 ioctl_names[_IOC_NR(cmd)] : "<invalid>", arg);
 426
 427         switch (cmd) {
 428         case VCHIQ_IOC_SHUTDOWN:
 429                 if (!instance->connected)
 430                         break;
 431
 432                 /* Remove all services */
 433                 i = 0;
 434                 while ((service = next_service_by_instance(instance->state,
 435                         instance, &i)) != NULL) {
 436                         status = vchiq_remove_service(service->handle);
 437                         unlock_service(service);
 438                         if (status != VCHIQ_SUCCESS)
 439                                 break;
 440                 }
 441                 service = NULL;
 442
 443                 if (status == VCHIQ_SUCCESS) {
 444                         /* Wake the completion thread and ask it to exit */
 445                         instance->closing = 1;
 446                         up(&instance->insert_event);
 447                 }
 448
 449                 break;
 450
 451         case VCHIQ_IOC_CONNECT:
 452                 if (instance->connected) {
 453                         ret = -EINVAL;
 454                         break;
 455                 }
 456                 rc = mutex_lock_interruptible(&instance->state->mutex);
 457                 if (rc != 0) {
 458                         vchiq_log_error(vchiq_arm_log_level,
 459                                 "vchiq: connect: could not lock mutex for "
 460                                 "state %d: %d",
 461                                 instance->state->id, rc);
 462                         ret = -EINTR;
 463                         break;
 464                 }
 465                 status = vchiq_connect_internal(instance->state, instance);
 466                 mutex_unlock(&instance->state->mutex);
 467
 468                 if (status == VCHIQ_SUCCESS)
 469                         instance->connected = 1;
 470                 else
 471                         vchiq_log_error(vchiq_arm_log_level,
 472                                 "vchiq: could not connect: %d", status);
 473                 break;
 474
 475         case VCHIQ_IOC_CREATE_SERVICE: {
 476                 VCHIQ_CREATE_SERVICE_T args;
 477                 USER_SERVICE_T *user_service = NULL;
 478                 void *userdata;
 479                 int srvstate;
 480
 481                 if (copy_from_user
 482                          (&args, (const void __user *)arg,
 483                           sizeof(args)) != 0) {
 484                         ret = -EFAULT;
 485                         break;
 486                 }
 487
 488                 user_service = kmalloc(sizeof(USER_SERVICE_T), GFP_KERNEL);
 489                 if (!user_service) {
 490                         ret = -ENOMEM;
 491                         break;
 492                 }
 493
 494                 if (args.is_open) {
 495                         if (!instance->connected) {
 496                                 ret = -ENOTCONN;
 497                                 kfree(user_service);
 498                                 break;
 499                         }
 500                         srvstate = VCHIQ_SRVSTATE_OPENING;
 501                 } else {
 502                         srvstate =
 503                                  instance->connected ?
 504                                  VCHIQ_SRVSTATE_LISTENING :
 505                                  VCHIQ_SRVSTATE_HIDDEN;
 506                 }
 507
 508                 userdata = args.params.userdata;
 509                 args.params.callback = service_callback;
 510                 args.params.userdata = user_service;
 511                 service = vchiq_add_service_internal(
 512                                 instance->state,
 513                                 &args.params, srvstate,
 514                                 instance, user_service_free);
 515
 516                 if (service != NULL) {
 517                         user_service->service = service;
 518                         user_service->userdata = userdata;
 519                         user_service->instance = instance;
 520                         user_service->is_vchi = (args.is_vchi != 0);
 521                         user_service->dequeue_pending = 0;
 522                         user_service->close_pending = 0;
 523                         user_service->message_available_pos =
 524                                 instance->completion_remove - 1;
 525                         user_service->msg_insert = 0;
 526                         user_service->msg_remove = 0;
 527                         sema_init(&user_service->insert_event, 0);
 528                         sema_init(&user_service->remove_event, 0);
 529                         sema_init(&user_service->close_event, 0);
 530
 531                         if (args.is_open) {
 532                                 status = vchiq_open_service_internal
 533                                         (service, instance->pid);
 534                                 if (status != VCHIQ_SUCCESS) {
 535                                         vchiq_remove_service(service->handle);
 536                                         service = NULL;
 537                                         ret = (status == VCHIQ_RETRY) ?
 538                                                 -EINTR : -EIO;
 539                                         break;
 540                                 }
 541                         }
 542
 543                         if (copy_to_user((void __user *)
 544                                 &(((VCHIQ_CREATE_SERVICE_T __user *)
 545                                         arg)->handle),
 546                                 (const void *)&service->handle,
 547                                 sizeof(service->handle)) != 0) {
 548                                 ret = -EFAULT;
 549                                 vchiq_remove_service(service->handle);
 550                         }
 551
 552                         service = NULL;
 553                 } else {
 554                         ret = -EEXIST;
 555                         kfree(user_service);
 556                 }
 557         } break;
 558
 559         case VCHIQ_IOC_CLOSE_SERVICE: {
 560                 VCHIQ_SERVICE_HANDLE_T handle = (VCHIQ_SERVICE_HANDLE_T)arg;
 561
 562                 service = find_service_for_instance(instance, handle);
 563                 if (service != NULL) {
 564                         USER_SERVICE_T *user_service =
 565                                 (USER_SERVICE_T *)service->base.userdata;
 566                         /* close_pending is false on first entry, and when the
 567                            wait in vchiq_close_service has been interrupted. */
 568                         if (!user_service->close_pending) {
 569                                 status = vchiq_close_service(service->handle);
 570                                 if (status != VCHIQ_SUCCESS)
 571                                         break;
 572                         }
 573
 574                         /* close_pending is true once the underlying service
 575                            has been closed until the client library calls the
 576                            CLOSE_DELIVERED ioctl, signalling close_event. */
 577                         if (user_service->close_pending &&
 578                                 down_interruptible(&user_service->close_event))
 579                                 status = VCHIQ_RETRY;
 580                 }
 581                 else
 582                         ret = -EINVAL;
 583         } break;
 584
 585         case VCHIQ_IOC_REMOVE_SERVICE: {
 586                 VCHIQ_SERVICE_HANDLE_T handle = (VCHIQ_SERVICE_HANDLE_T)arg;
 587
 588                 service = find_service_for_instance(instance, handle);
 589                 if (service != NULL) {
 590                         USER_SERVICE_T *user_service =
 591                                 (USER_SERVICE_T *)service->base.userdata;
 592                         /* close_pending is false on first entry, and when the
 593                            wait in vchiq_close_service has been interrupted. */
 594                         if (!user_service->close_pending) {
 595                                 status = vchiq_remove_service(service->handle);
 596                                 if (status != VCHIQ_SUCCESS)
 597                                         break;
 598                         }
 599
 600                         /* close_pending is true once the underlying service
 601                            has been closed until the client library calls the
 602                            CLOSE_DELIVERED ioctl, signalling close_event. */
 603                         if (user_service->close_pending &&
 604                                 down_interruptible(&user_service->close_event))
 605                                 status = VCHIQ_RETRY;
 606                 }
 607                 else
 608                         ret = -EINVAL;
 609         } break;
 610
 611         case VCHIQ_IOC_USE_SERVICE:
 612         case VCHIQ_IOC_RELEASE_SERVICE: {
 613                 VCHIQ_SERVICE_HANDLE_T handle = (VCHIQ_SERVICE_HANDLE_T)arg;
 614
 615                 service = find_service_for_instance(instance, handle);
 616                 if (service != NULL) {
 617                         status = (cmd == VCHIQ_IOC_USE_SERVICE) ?
 618                                 vchiq_use_service_internal(service) :
 619                                 vchiq_release_service_internal(service);
 620                         if (status != VCHIQ_SUCCESS) {
 621                                 vchiq_log_error(vchiq_susp_log_level,
 622                                         "%s: cmd %s returned error %d for "
 623                                         "service %c%c%c%c:%03d",
 624                                         __func__,
 625                                         (cmd == VCHIQ_IOC_USE_SERVICE) ?
 626                                                 "VCHIQ_IOC_USE_SERVICE" :
 627                                                 "VCHIQ_IOC_RELEASE_SERVICE",
 628                                         status,
 629                                         VCHIQ_FOURCC_AS_4CHARS(
 630                                                 service->base.fourcc),
 631                                         service->client_id);
 632                                 ret = -EINVAL;
 633                         }
 634                 } else
 635                         ret = -EINVAL;
 636         } break;
 637
 638         case VCHIQ_IOC_QUEUE_MESSAGE: {
 639                 VCHIQ_QUEUE_MESSAGE_T args;
 640                 if (copy_from_user
 641                          (&args, (const void __user *)arg,
 642                           sizeof(args)) != 0) {
 643                         ret = -EFAULT;
 644                         break;
 645                 }
 646
 647                 service = find_service_for_instance(instance, args.handle);
 648
 649                 if ((service != NULL) && (args.count <= MAX_ELEMENTS)) {
 650                         /* Copy elements into kernel space */
 651                         VCHIQ_ELEMENT_T elements[MAX_ELEMENTS];
 652                         if (copy_from_user(elements, args.elements,
 653                                 args.count * sizeof(VCHIQ_ELEMENT_T)) == 0)
 654                                 status = vchiq_queue_message
 655                                         (args.handle,
 656                                         elements, args.count);
 657                         else
 658                                 ret = -EFAULT;
 659                 } else {
 660                         ret = -EINVAL;
 661                 }
 662         } break;
 663
 664         case VCHIQ_IOC_QUEUE_BULK_TRANSMIT:
 665         case VCHIQ_IOC_QUEUE_BULK_RECEIVE: {
 666                 VCHIQ_QUEUE_BULK_TRANSFER_T args;
 667                 struct bulk_waiter_node *waiter = NULL;
 668                 VCHIQ_BULK_DIR_T dir =
 669                         (cmd == VCHIQ_IOC_QUEUE_BULK_TRANSMIT) ?
 670                         VCHIQ_BULK_TRANSMIT : VCHIQ_BULK_RECEIVE;
 671
 672                 if (copy_from_user
 673                         (&args, (const void __user *)arg,
 674                         sizeof(args)) != 0) {
 675                         ret = -EFAULT;
 676                         break;
 677                 }
 678
 679                 service = find_service_for_instance(instance, args.handle);
 680                 if (!service) {
 681                         ret = -EINVAL;
 682                         break;
 683                 }
 684
 685                 if (args.mode == VCHIQ_BULK_MODE_BLOCKING) {
 686                         waiter = kzalloc(sizeof(struct bulk_waiter_node),
 687                                 GFP_KERNEL);
 688                         if (!waiter) {
 689                                 ret = -ENOMEM;
 690                                 break;
 691                         }
 692                         args.userdata = &waiter->bulk_waiter;
 693                 } else if (args.mode == VCHIQ_BULK_MODE_WAITING) {
 694                         struct list_head *pos;
 695                         mutex_lock(&instance->bulk_waiter_list_mutex);
 696                         list_for_each(pos, &instance->bulk_waiter_list) {
 697                                 if (list_entry(pos, struct bulk_waiter_node,
 698                                         list)->pid == current->pid) {
 699                                         waiter = list_entry(pos,
 700                                                 struct bulk_waiter_node,
 701                                                 list);
 702                                         list_del(pos);
 703                                         break;
 704                                 }
 705
 706                         }
 707                         mutex_unlock(&instance->bulk_waiter_list_mutex);
 708                         if (!waiter) {
 709                                 vchiq_log_error(vchiq_arm_log_level,
 710                                         "no bulk_waiter found for pid %d",
 711                                         current->pid);
 712                                 ret = -ESRCH;
 713                                 break;
 714                         }
 715                         vchiq_log_info(vchiq_arm_log_level,
 716                                 "found bulk_waiter %x for pid %d",
 717                                 (unsigned int)waiter, current->pid);
 718                         args.userdata = &waiter->bulk_waiter;
 719                 }
 720                 status = vchiq_bulk_transfer
 721                         (args.handle,
 722                          VCHI_MEM_HANDLE_INVALID,
 723                          args.data, args.size,
 724                          args.userdata, args.mode,
 725                          dir);
 726                 if (!waiter)
 727                         break;
 728                 if ((status != VCHIQ_RETRY) || fatal_signal_pending(current) ||
 729                         !waiter->bulk_waiter.bulk) {
 730                         if (waiter->bulk_waiter.bulk) {
 731                                 /* Cancel the signal when the transfer
 732                                 ** completes. */
 733                                 spin_lock(&bulk_waiter_spinlock);
 734                                 waiter->bulk_waiter.bulk->userdata = NULL;
 735                                 spin_unlock(&bulk_waiter_spinlock);
 736                         }
 737                         kfree(waiter);
 738                 } else {
 739                         const VCHIQ_BULK_MODE_T mode_waiting =
 740                                 VCHIQ_BULK_MODE_WAITING;
 741                         waiter->pid = current->pid;
 742                         mutex_lock(&instance->bulk_waiter_list_mutex);
 743                         list_add(&waiter->list, &instance->bulk_waiter_list);
 744                         mutex_unlock(&instance->bulk_waiter_list_mutex);
 745                         vchiq_log_info(vchiq_arm_log_level,
 746                                 "saved bulk_waiter %x for pid %d",
 747                                 (unsigned int)waiter, current->pid);
 748
 749                         if (copy_to_user((void __user *)
 750                                 &(((VCHIQ_QUEUE_BULK_TRANSFER_T __user *)
 751                                         arg)->mode),
 752                                 (const void *)&mode_waiting,
 753                                 sizeof(mode_waiting)) != 0)
 754                                 ret = -EFAULT;
 755                 }
 756         } break;
 757
 758         case VCHIQ_IOC_AWAIT_COMPLETION: {
 759                 VCHIQ_AWAIT_COMPLETION_T args;
 760
 761                 DEBUG_TRACE(AWAIT_COMPLETION_LINE);
 762                 if (!instance->connected) {
 763                         ret = -ENOTCONN;
 764                         break;
 765                 }
 766
 767                 if (copy_from_user(&args, (const void __user *)arg,
 768                         sizeof(args)) != 0) {
 769                         ret = -EFAULT;
 770                         break;
 771                 }
 772
 773                 mutex_lock(&instance->completion_mutex);
 774
 775                 DEBUG_TRACE(AWAIT_COMPLETION_LINE);
 776                 while ((instance->completion_remove ==
 777                         instance->completion_insert)
 778                         && !instance->closing) {
 779                         int rc;
 780                         DEBUG_TRACE(AWAIT_COMPLETION_LINE);
 781                         mutex_unlock(&instance->completion_mutex);
 782                         rc = down_interruptible(&instance->insert_event);
 783                         mutex_lock(&instance->completion_mutex);
 784                         if (rc != 0) {
 785                                 DEBUG_TRACE(AWAIT_COMPLETION_LINE);
 786                                 vchiq_log_info(vchiq_arm_log_level,
 787                                         "AWAIT_COMPLETION interrupted");
 788                                 ret = -EINTR;
 789                                 break;
 790                         }
 791                 }
 792                 DEBUG_TRACE(AWAIT_COMPLETION_LINE);
 793
 794                 /* A read memory barrier is needed to stop prefetch of a stale
 795                 ** completion record
 796                 */
 797                 rmb();
 798
 799                 if (ret == 0) {
 800                         int msgbufcount = args.msgbufcount;
 801                         for (ret = 0; ret < args.count; ret++) {
 802                                 VCHIQ_COMPLETION_DATA_T *completion;
 803                                 VCHIQ_SERVICE_T *service;
 804                                 USER_SERVICE_T *user_service;
 805                                 VCHIQ_HEADER_T *header;
 806                                 if (instance->completion_remove ==
 807                                         instance->completion_insert)
 808                                         break;
 809                                 completion = &instance->completions[
 810                                         instance->completion_remove &
 811                                         (MAX_COMPLETIONS - 1)];
 812
 813                                 service = completion->service_userdata;
 814                                 user_service = service->base.userdata;
 815                                 completion->service_userdata =
 816                                         user_service->userdata;
 817
 818                                 header = completion->header;
 819                                 if (header) {
 820                                         void __user *msgbuf;
 821                                         int msglen;
 822
 823                                         msglen = header->size +
 824                                                 sizeof(VCHIQ_HEADER_T);
 825                                         /* This must be a VCHIQ-style service */
 826                                         if (args.msgbufsize < msglen) {
 827                                                 vchiq_log_error(
 828                                                         vchiq_arm_log_level,
 829                                                         "header %x: msgbufsize"
 830                                                         " %x < msglen %x",
 831                                                         (unsigned int)header,
 832                                                         args.msgbufsize,
 833                                                         msglen);
 834                                                 WARN(1, "invalid message "
 835                                                         "size\n");
 836                                                 if (ret == 0)
 837                                                         ret = -EMSGSIZE;
 838                                                 break;
 839                                         }
 840                                         if (msgbufcount <= 0)
 841                                                 /* Stall here for lack of a
 842                                                 ** buffer for the message. */
 843                                                 break;
 844                                         /* Get the pointer from user space */
 845                                         msgbufcount--;
 846                                         if (copy_from_user(&msgbuf,
 847                                                 (const void __user *)
 848                                                 &args.msgbufs[msgbufcount],
 849                                                 sizeof(msgbuf)) != 0) {
 850                                                 if (ret == 0)
 851                                                         ret = -EFAULT;
 852                                                 break;
 853                                         }
 854
 855                                         /* Copy the message to user space */
 856                                         if (copy_to_user(msgbuf, header,
 857                                                 msglen) != 0) {
 858                                                 if (ret == 0)
 859                                                         ret = -EFAULT;
 860                                                 break;
 861                                         }
 862
 863                                         /* Now it has been copied, the message
 864                                         ** can be released. */
 865                                         vchiq_release_message(service->handle,
 866                                                 header);
 867
 868                                         /* The completion must point to the
 869                                         ** msgbuf. */
 870                                         completion->header = msgbuf;
 871                                 }
 872
 873                                 if ((completion->reason ==
 874                                         VCHIQ_SERVICE_CLOSED) &&
 875                                         !instance->use_close_delivered)
 876                                         unlock_service(service);
 877
 878                                 if (copy_to_user((void __user *)(
 879                                         (size_t)args.buf +
 880                                         ret * sizeof(VCHIQ_COMPLETION_DATA_T)),
 881                                         completion,
 882                                         sizeof(VCHIQ_COMPLETION_DATA_T)) != 0) {
 883                                                 if (ret == 0)
 884                                                         ret = -EFAULT;
 885                                         break;
 886                                 }
 887
 888                                 instance->completion_remove++;
 889                         }
 890
 891                         if (msgbufcount != args.msgbufcount) {
 892                                 if (copy_to_user((void __user *)
 893                                         &((VCHIQ_AWAIT_COMPLETION_T *)arg)->
 894                                                 msgbufcount,
 895                                         &msgbufcount,
 896                                         sizeof(msgbufcount)) != 0) {
 897                                         ret = -EFAULT;
 898                                 }
 899                         }
 900                 }
 901
 902                 if (ret != 0)
 903                         up(&instance->remove_event);
 904                 mutex_unlock(&instance->completion_mutex);
 905                 DEBUG_TRACE(AWAIT_COMPLETION_LINE);
 906         } break;
 907
 908         case VCHIQ_IOC_DEQUEUE_MESSAGE: {
 909                 VCHIQ_DEQUEUE_MESSAGE_T args;
 910                 USER_SERVICE_T *user_service;
 911                 VCHIQ_HEADER_T *header;
 912
 913                 DEBUG_TRACE(DEQUEUE_MESSAGE_LINE);
 914                 if (copy_from_user
 915                          (&args, (const void __user *)arg,
 916                           sizeof(args)) != 0) {
 917                         ret = -EFAULT;
 918                         break;
 919                 }
 920                 service = find_service_for_instance(instance, args.handle);
 921                 if (!service) {
 922                         ret = -EINVAL;
 923                         break;
 924                 }
 925                 user_service = (USER_SERVICE_T *)service->base.userdata;
 926                 if (user_service->is_vchi == 0) {
 927                         ret = -EINVAL;
 928                         break;
 929                 }
 930
 931                 spin_lock(&msg_queue_spinlock);
 932                 if (user_service->msg_remove == user_service->msg_insert) {
 933                         if (!args.blocking) {
 934                                 spin_unlock(&msg_queue_spinlock);
 935                                 DEBUG_TRACE(DEQUEUE_MESSAGE_LINE);
 936                                 ret = -EWOULDBLOCK;
 937                                 break;
 938                         }
 939                         user_service->dequeue_pending = 1;
 940                         do {
 941                                 spin_unlock(&msg_queue_spinlock);
 942                                 DEBUG_TRACE(DEQUEUE_MESSAGE_LINE);
 943                                 if (down_interruptible(
 944                                         &user_service->insert_event) != 0) {
 945                                         vchiq_log_info(vchiq_arm_log_level,
 946                                                 "DEQUEUE_MESSAGE interrupted");
 947                                         ret = -EINTR;
 948                                         break;
 949                                 }
 950                                 spin_lock(&msg_queue_spinlock);
 951                         } while (user_service->msg_remove ==
 952                                 user_service->msg_insert);
 953
 954                         if (ret)
 955                                 break;
 956                 }
 957
 958                 BUG_ON((int)(user_service->msg_insert -
 959                         user_service->msg_remove) < 0);
 960
 961                 header = user_service->msg_queue[user_service->msg_remove &
 962                         (MSG_QUEUE_SIZE - 1)];
 963                 user_service->msg_remove++;
 964                 spin_unlock(&msg_queue_spinlock);
 965
 966                 up(&user_service->remove_event);
 967                 if (header == NULL)
 968                         ret = -ENOTCONN;
 969                 else if (header->size <= args.bufsize) {
 970                         /* Copy to user space if msgbuf is not NULL */
 971                         if ((args.buf == NULL) ||
 972                                 (copy_to_user((void __user *)args.buf,
 973                                 header->data,
 974                                 header->size) == 0)) {
 975                                 ret = header->size;
 976                                 vchiq_release_message(
 977                                         service->handle,
 978                                         header);
 979                         } else
 980                                 ret = -EFAULT;
 981                 } else {
 982                         vchiq_log_error(vchiq_arm_log_level,
 983                                 "header %x: bufsize %x < size %x",
 984                                 (unsigned int)header, args.bufsize,
 985                                 header->size);
 986                         WARN(1, "invalid size\n");
 987                         ret = -EMSGSIZE;
 988                 }
 989                 DEBUG_TRACE(DEQUEUE_MESSAGE_LINE);
 990         } break;
 991
 992         case VCHIQ_IOC_GET_CLIENT_ID: {
 993                 VCHIQ_SERVICE_HANDLE_T handle = (VCHIQ_SERVICE_HANDLE_T)arg;
 994
 995                 ret = vchiq_get_client_id(handle);
 996         } break;
 997
 998         case VCHIQ_IOC_GET_CONFIG: {
 999                 VCHIQ_GET_CONFIG_T args;
1000                 VCHIQ_CONFIG_T config;
1001
1002                 if (copy_from_user(&args, (const void __user *)arg,
1003                         sizeof(args)) != 0) {
1004                         ret = -EFAULT;
1005                         break;
1006                 }
1007                 if (args.config_size > sizeof(config)) {
1008                         ret = -EINVAL;
1009                         break;
1010                 }
1011                 status = vchiq_get_config(instance, args.config_size, &config);
1012                 if (status == VCHIQ_SUCCESS) {
1013                         if (copy_to_user((void __user *)args.pconfig,
1014                                     &config, args.config_size) != 0) {
1015                                 ret = -EFAULT;
1016                                 break;
1017                         }
1018                 }
1019         } break;
1020
1021         case VCHIQ_IOC_SET_SERVICE_OPTION: {
1022                 VCHIQ_SET_SERVICE_OPTION_T args;
1023
1024                 if (copy_from_user(
1025                         &args, (const void __user *)arg,
1026                         sizeof(args)) != 0) {
1027                         ret = -EFAULT;
1028                         break;
1029                 }
1030
1031                 service = find_service_for_instance(instance, args.handle);
1032                 if (!service) {
1033                         ret = -EINVAL;
1034                         break;
1035                 }
1036
1037                 status = vchiq_set_service_option(
1038                                 args.handle, args.option, args.value);
1039         } break;
1040
1041         case VCHIQ_IOC_DUMP_PHYS_MEM: {
1042                 VCHIQ_DUMP_MEM_T  args;
1043
1044                 if (copy_from_user
1045                          (&args, (const void __user *)arg,
1046                           sizeof(args)) != 0) {
1047                         ret = -EFAULT;
1048                         break;
1049                 }
1050                 dump_phys_mem(args.virt_addr, args.num_bytes);
1051         } break;
1052
1053         case VCHIQ_IOC_LIB_VERSION: {
1054                 unsigned int lib_version = (unsigned int)arg;
1055
1056                 if (lib_version < VCHIQ_VERSION_MIN)
1057                         ret = -EINVAL;
1058                 else if (lib_version >= VCHIQ_VERSION_CLOSE_DELIVERED)
1059                         instance->use_close_delivered = 1;
1060         } break;
1061
1062         case VCHIQ_IOC_CLOSE_DELIVERED: {
1063                 VCHIQ_SERVICE_HANDLE_T handle = (VCHIQ_SERVICE_HANDLE_T)arg;
1064
1065                 service = find_closed_service_for_instance(instance, handle);
1066                 if (service != NULL) {
1067                         USER_SERVICE_T *user_service =
1068                                 (USER_SERVICE_T *)service->base.userdata;
1069                         close_delivered(user_service);
1070                 }
1071                 else
1072                         ret = -EINVAL;
1073         } break;
1074
1075         default:
1076                 ret = -ENOTTY;
1077                 break;
1078         }
1079
1080         if (service)
1081                 unlock_service(service);
1082
1083         if (ret == 0) {
1084                 if (status == VCHIQ_ERROR)
1085                         ret = -EIO;
1086                 else if (status == VCHIQ_RETRY)
1087                         ret = -EINTR;
1088         }
1089
1090         if ((status == VCHIQ_SUCCESS) && (ret < 0) && (ret != -EINTR) &&
1091                 (ret != -EWOULDBLOCK))
1092                 vchiq_log_info(vchiq_arm_log_level,
1093                         "  ioctl instance %lx, cmd %s -> status %d, %ld",
1094                         (unsigned long)instance,
1095                         (_IOC_NR(cmd) <= VCHIQ_IOC_MAX) ?
1096                                 ioctl_names[_IOC_NR(cmd)] :
1097                                 "<invalid>",
1098                         status, ret);
1099         else
1100                 vchiq_log_trace(vchiq_arm_log_level,
1101                         "  ioctl instance %lx, cmd %s -> status %d, %ld",
1102                         (unsigned long)instance,
1103                         (_IOC_NR(cmd) <= VCHIQ_IOC_MAX) ?
1104                                 ioctl_names[_IOC_NR(cmd)] :
1105                                 "<invalid>",
1106                         status, ret);
1107
1108         return ret;
1109 }
1110
1111 /****************************************************************************
1112 *
1113 *   vchiq_open
1114 *
1115 ***************************************************************************/
1116
1117 static int
1118 vchiq_open(struct inode *inode, struct file *file)
1119 {
1120         int dev = iminor(inode) & 0x0f;
1121         vchiq_log_info(vchiq_arm_log_level, "vchiq_open");
1122         switch (dev) {
1123         case VCHIQ_MINOR: {
1124                 int ret;
1125                 VCHIQ_STATE_T *state = vchiq_get_state();
1126                 VCHIQ_INSTANCE_T instance;
1127
1128                 if (!state) {
1129                         vchiq_log_error(vchiq_arm_log_level,
1130                                 "vchiq has no connection to VideoCore");
1131                         return -ENOTCONN;
1132                 }
1133
1134                 instance = kzalloc(sizeof(*instance), GFP_KERNEL);
1135                 if (!instance)
1136                         return -ENOMEM;
1137
1138                 instance->state = state;
1139                 instance->pid = current->tgid;
1140
1141                 ret = vchiq_debugfs_add_instance(instance);
1142                 if (ret != 0) {
1143                         kfree(instance);
1144                         return ret;
1145                 }
1146
1147                 sema_init(&instance->insert_event, 0);
1148                 sema_init(&instance->remove_event, 0);
1149                 mutex_init(&instance->completion_mutex);
1150                 mutex_init(&instance->bulk_waiter_list_mutex);
1151                 INIT_LIST_HEAD(&instance->bulk_waiter_list);
1152
1153                 file->private_data = instance;
1154         } break;
1155
1156         default:
1157                 vchiq_log_error(vchiq_arm_log_level,
1158                         "Unknown minor device: %d", dev);
1159                 return -ENXIO;
1160         }
1161
1162         return 0;
1163 }
1164
1165 /****************************************************************************
1166 *
1167 *   vchiq_release
1168 *
1169 ***************************************************************************/
1170
1171 static int
1172 vchiq_release(struct inode *inode, struct file *file)
1173 {
1174         int dev = iminor(inode) & 0x0f;
1175         int ret = 0;
1176         switch (dev) {
1177         case VCHIQ_MINOR: {
1178                 VCHIQ_INSTANCE_T instance = file->private_data;
1179                 VCHIQ_STATE_T *state = vchiq_get_state();
1180                 VCHIQ_SERVICE_T *service;
1181                 int i;
1182
1183                 vchiq_log_info(vchiq_arm_log_level,
1184                         "vchiq_release: instance=%lx",
1185                         (unsigned long)instance);
1186
1187                 if (!state) {
1188                         ret = -EPERM;
1189                         goto out;
1190                 }
1191
1192                 /* Ensure videocore is awake to allow termination. */
1193                 vchiq_use_internal(instance->state, NULL,
1194                                 USE_TYPE_VCHIQ);
1195
1196                 mutex_lock(&instance->completion_mutex);
1197
1198                 /* Wake the completion thread and ask it to exit */
1199                 instance->closing = 1;
1200                 up(&instance->insert_event);
1201
1202                 mutex_unlock(&instance->completion_mutex);
1203
1204                 /* Wake the slot handler if the completion queue is full. */
1205                 up(&instance->remove_event);
1206
1207                 /* Mark all services for termination... */
1208                 i = 0;
1209                 while ((service = next_service_by_instance(state, instance,
1210                         &i)) != NULL) {
1211                         USER_SERVICE_T *user_service = service->base.userdata;
1212
1213                         /* Wake the slot handler if the msg queue is full. */
1214                         up(&user_service->remove_event);
1215
1216                         vchiq_terminate_service_internal(service);
1217                         unlock_service(service);
1218                 }
1219
1220                 /* ...and wait for them to die */
1221                 i = 0;
1222                 while ((service = next_service_by_instance(state, instance, &i))
1223                         != NULL) {
1224                         USER_SERVICE_T *user_service = service->base.userdata;
1225
1226                         down(&service->remove_event);
1227
1228                         BUG_ON(service->srvstate != VCHIQ_SRVSTATE_FREE);
1229
1230                         spin_lock(&msg_queue_spinlock);
1231
1232                         while (user_service->msg_remove !=
1233                                 user_service->msg_insert) {
1234                                 VCHIQ_HEADER_T *header = user_service->
1235                                         msg_queue[user_service->msg_remove &
1236                                                 (MSG_QUEUE_SIZE - 1)];
1237                                 user_service->msg_remove++;
1238                                 spin_unlock(&msg_queue_spinlock);
1239
1240                                 if (header)
1241                                         vchiq_release_message(
1242                                                 service->handle,
1243                                                 header);
1244                                 spin_lock(&msg_queue_spinlock);
1245                         }
1246
1247                         spin_unlock(&msg_queue_spinlock);
1248
1249                         unlock_service(service);
1250                 }
1251
1252                 /* Release any closed services */
1253                 while (instance->completion_remove !=
1254                         instance->completion_insert) {
1255                         VCHIQ_COMPLETION_DATA_T *completion;
1256                         VCHIQ_SERVICE_T *service;
1257                         completion = &instance->completions[
1258                                 instance->completion_remove &
1259                                 (MAX_COMPLETIONS - 1)];
1260                         service = completion->service_userdata;
1261                         if (completion->reason == VCHIQ_SERVICE_CLOSED)
1262                         {
1263                                 USER_SERVICE_T *user_service =
1264                                         service->base.userdata;
1265
1266                                 /* Wake any blocked user-thread */
1267                                 if (instance->use_close_delivered)
1268                                         up(&user_service->close_event);
1269                                 unlock_service(service);
1270                         }
1271                         instance->completion_remove++;
1272                 }
1273
1274                 /* Release the PEER service count. */
1275                 vchiq_release_internal(instance->state, NULL);
1276
1277                 {
1278                         struct list_head *pos, *next;
1279                         list_for_each_safe(pos, next,
1280                                 &instance->bulk_waiter_list) {
1281                                 struct bulk_waiter_node *waiter;
1282                                 waiter = list_entry(pos,
1283                                         struct bulk_waiter_node,
1284                                         list);
1285                                 list_del(pos);
1286                                 vchiq_log_info(vchiq_arm_log_level,
1287                                         "bulk_waiter - cleaned up %x "
1288                                         "for pid %d",
1289                                         (unsigned int)waiter, waiter->pid);
1290                                 kfree(waiter);
1291                         }
1292                 }
1293
1294                 vchiq_debugfs_remove_instance(instance);
1295
1296                 kfree(instance);
1297                 file->private_data = NULL;
1298         } break;
1299
1300         default:
1301                 vchiq_log_error(vchiq_arm_log_level,
1302                         "Unknown minor device: %d", dev);
1303                 ret = -ENXIO;
1304         }
1305
1306 out:
1307         return ret;
1308 }
1309
1310 /****************************************************************************
1311 *
1312 *   vchiq_dump
1313 *
1314 ***************************************************************************/
1315
1316 void
1317 vchiq_dump(void *dump_context, const char *str, int len)
1318 {
1319         DUMP_CONTEXT_T *context = (DUMP_CONTEXT_T *)dump_context;
1320
1321         if (context->actual < context->space) {
1322                 int copy_bytes;
1323                 if (context->offset > 0) {
1324                         int skip_bytes = min(len, (int)context->offset);
1325                         str += skip_bytes;
1326                         len -= skip_bytes;
1327                         context->offset -= skip_bytes;
1328                         if (context->offset > 0)
1329                                 return;
1330                 }
1331                 copy_bytes = min(len, (int)(context->space - context->actual));
1332                 if (copy_bytes == 0)
1333                         return;
1334                 if (copy_to_user(context->buf + context->actual, str,
1335                         copy_bytes))
1336                         context->actual = -EFAULT;
1337                 context->actual += copy_bytes;
1338                 len -= copy_bytes;
1339
1340                 /* If tne terminating NUL is included in the length, then it
1341                 ** marks the end of a line and should be replaced with a
1342                 ** carriage return. */
1343                 if ((len == 0) && (str[copy_bytes - 1] == '\0')) {
1344                         char cr = '\n';
1345                         if (copy_to_user(context->buf + context->actual - 1,
1346                                 &cr, 1))
1347                                 context->actual = -EFAULT;
1348                 }
1349         }
1350 }
1351
1352 /****************************************************************************
1353 *
1354 *   vchiq_dump_platform_instance_state
1355 *
1356 ***************************************************************************/
1357
1358 void
1359 vchiq_dump_platform_instances(void *dump_context)
1360 {
1361         VCHIQ_STATE_T *state = vchiq_get_state();
1362         char buf[80];
1363         int len;
1364         int i;
1365
1366         /* There is no list of instances, so instead scan all services,
1367                 marking those that have been dumped. */
1368
1369         for (i = 0; i < state->unused_service; i++) {
1370                 VCHIQ_SERVICE_T *service = state->services[i];
1371                 VCHIQ_INSTANCE_T instance;
1372
1373                 if (service && (service->base.callback == service_callback)) {
1374                         instance = service->instance;
1375                         if (instance)
1376                                 instance->mark = 0;
1377                 }
1378         }
1379
1380         for (i = 0; i < state->unused_service; i++) {
1381                 VCHIQ_SERVICE_T *service = state->services[i];
1382                 VCHIQ_INSTANCE_T instance;
1383
1384                 if (service && (service->base.callback == service_callback)) {
1385                         instance = service->instance;
1386                         if (instance && !instance->mark) {
1387                                 len = snprintf(buf, sizeof(buf),
1388                                         "Instance %x: pid %d,%s completions "
1389                                                 "%d/%d",
1390                                         (unsigned int)instance, instance->pid,
1391                                         instance->connected ? " connected, " :
1392                                                 "",
1393                                         instance->completion_insert -
1394                                                 instance->completion_remove,
1395                                         MAX_COMPLETIONS);
1396
1397                                 vchiq_dump(dump_context, buf, len + 1);
1398
1399                                 instance->mark = 1;
1400                         }
1401                 }
1402         }
1403 }
1404
1405 /****************************************************************************
1406 *
1407 *   vchiq_dump_platform_service_state
1408 *
1409 ***************************************************************************/
1410
1411 void
1412 vchiq_dump_platform_service_state(void *dump_context, VCHIQ_SERVICE_T *service)
1413 {
1414         USER_SERVICE_T *user_service = (USER_SERVICE_T *)service->base.userdata;
1415         char buf[80];
1416         int len;
1417
1418         len = snprintf(buf, sizeof(buf), "  instance %x",
1419                 (unsigned int)service->instance);
1420
1421         if ((service->base.callback == service_callback) &&
1422                 user_service->is_vchi) {
1423                 len += snprintf(buf + len, sizeof(buf) - len,
1424                         ", %d/%d messages",
1425                         user_service->msg_insert - user_service->msg_remove,
1426                         MSG_QUEUE_SIZE);
1427
1428                 if (user_service->dequeue_pending)
1429                         len += snprintf(buf + len, sizeof(buf) - len,
1430                                 " (dequeue pending)");
1431         }
1432
1433         vchiq_dump(dump_context, buf, len + 1);
1434 }
1435
1436 /****************************************************************************
1437 *
1438 *   dump_user_mem
1439 *
1440 ***************************************************************************/
1441
1442 static void
1443 dump_phys_mem(void *virt_addr, uint32_t num_bytes)
1444 {
1445         int            rc;
1446         uint8_t       *end_virt_addr = virt_addr + num_bytes;
1447         int            num_pages;
1448         int            offset;
1449         int            end_offset;
1450         int            page_idx;
1451         int            prev_idx;
1452         struct page   *page;
1453         struct page  **pages;
1454         uint8_t       *kmapped_virt_ptr;
1455
1456         /* Align virtAddr and endVirtAddr to 16 byte boundaries. */
1457
1458         virt_addr = (void *)((unsigned long)virt_addr & ~0x0fuL);
1459         end_virt_addr = (void *)(((unsigned long)end_virt_addr + 15uL) &
1460                 ~0x0fuL);
1461
1462         offset = (int)(long)virt_addr & (PAGE_SIZE - 1);
1463         end_offset = (int)(long)end_virt_addr & (PAGE_SIZE - 1);
1464
1465         num_pages = (offset + num_bytes + PAGE_SIZE - 1) / PAGE_SIZE;
1466
1467         pages = kmalloc(sizeof(struct page *) * num_pages, GFP_KERNEL);
1468         if (pages == NULL) {
1469                 vchiq_log_error(vchiq_arm_log_level,
1470                         "Unable to allocation memory for %d pages\n",
1471                         num_pages);
1472                 return;
1473         }
1474
1475         down_read(&current->mm->mmap_sem);
1476         rc = get_user_pages(current,      /* task */
1477                 current->mm,              /* mm */
1478                 (unsigned long)virt_addr, /* start */
1479                 num_pages,                /* len */
1480                 0,                        /* gup_flags */
1481                 pages,                    /* pages (array of page pointers) */
1482                 NULL);                    /* vmas */
1483         up_read(&current->mm->mmap_sem);
1484
1485         prev_idx = -1;
1486         page = NULL;
1487
1488         while (offset < end_offset) {
1489
1490                 int page_offset = offset % PAGE_SIZE;
1491                 page_idx = offset / PAGE_SIZE;
1492
1493                 if (page_idx != prev_idx) {
1494
1495                         if (page != NULL)
1496                                 kunmap(page);
1497                         page = pages[page_idx];
1498                         kmapped_virt_ptr = kmap(page);
1499
1500                         prev_idx = page_idx;
1501                 }
1502
1503                 if (vchiq_arm_log_level >= VCHIQ_LOG_TRACE)
1504                         vchiq_log_dump_mem("ph",
1505                                 (uint32_t)(unsigned long)&kmapped_virt_ptr[
1506                                         page_offset],
1507                                 &kmapped_virt_ptr[page_offset], 16);
1508
1509                 offset += 16;
1510         }
1511         if (page != NULL)
1512                 kunmap(page);
1513
1514         for (page_idx = 0; page_idx < num_pages; page_idx++)
1515                 page_cache_release(pages[page_idx]);
1516
1517         kfree(pages);
1518 }
1519
1520 /****************************************************************************
1521 *
1522 *   vchiq_read
1523 *
1524 ***************************************************************************/
1525
1526 static ssize_t
1527 vchiq_read(struct file *file, char __user *buf,
1528         size_t count, loff_t *ppos)
1529 {
1530         DUMP_CONTEXT_T context;
1531         context.buf = buf;
1532         context.actual = 0;
1533         context.space = count;
1534         context.offset = *ppos;
1535
1536         vchiq_dump_state(&context, &g_state);
1537
1538         *ppos += context.actual;
1539
1540         return context.actual;
1541 }
1542
1543 VCHIQ_STATE_T *
1544 vchiq_get_state(void)
1545 {
1546
1547         if (g_state.remote == NULL)
1548                 printk(KERN_ERR "%s: g_state.remote == NULL\n", __func__);
1549         else if (g_state.remote->initialised != 1)
1550                 printk(KERN_NOTICE "%s: g_state.remote->initialised != 1 (%d)\n",
1551                         __func__, g_state.remote->initialised);
1552
1553         return ((g_state.remote != NULL) &&
1554                 (g_state.remote->initialised == 1)) ? &g_state : NULL;
1555 }
1556
1557 static const struct file_operations
1558 vchiq_fops = {
1559         .owner = THIS_MODULE,
1560         .unlocked_ioctl = vchiq_ioctl,
1561         .open = vchiq_open,
1562         .release = vchiq_release,
1563         .read = vchiq_read
1564 };
1565
1566 /*
1567  * Autosuspend related functionality
1568  */
1569
1570 int
1571 vchiq_videocore_wanted(VCHIQ_STATE_T *state)
1572 {
1573         VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
1574         if (!arm_state)
1575                 /* autosuspend not supported - always return wanted */
1576                 return 1;
1577         else if (arm_state->blocked_count)
1578                 return 1;
1579         else if (!arm_state->videocore_use_count)
1580                 /* usage count zero - check for override unless we're forcing */
1581                 if (arm_state->resume_blocked)
1582                         return 0;
1583                 else
1584                         return vchiq_platform_videocore_wanted(state);
1585         else
1586                 /* non-zero usage count - videocore still required */
1587                 return 1;
1588 }
1589
1590 static VCHIQ_STATUS_T
1591 vchiq_keepalive_vchiq_callback(VCHIQ_REASON_T reason,
1592         VCHIQ_HEADER_T *header,
1593         VCHIQ_SERVICE_HANDLE_T service_user,
1594         void *bulk_user)
1595 {
1596         vchiq_log_error(vchiq_susp_log_level,
1597                 "%s callback reason %d", __func__, reason);
1598         return 0;
1599 }
1600
1601 static int
1602 vchiq_keepalive_thread_func(void *v)
1603 {
1604         VCHIQ_STATE_T *state = (VCHIQ_STATE_T *) v;
1605         VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
1606
1607         VCHIQ_STATUS_T status;
1608         VCHIQ_INSTANCE_T instance;
1609         VCHIQ_SERVICE_HANDLE_T ka_handle;
1610
1611         VCHIQ_SERVICE_PARAMS_T params = {
1612                 .fourcc      = VCHIQ_MAKE_FOURCC('K', 'E', 'E', 'P'),
1613                 .callback    = vchiq_keepalive_vchiq_callback,
1614                 .version     = KEEPALIVE_VER,
1615                 .version_min = KEEPALIVE_VER_MIN
1616         };
1617
1618         status = vchiq_initialise(&instance);
1619         if (status != VCHIQ_SUCCESS) {
1620                 vchiq_log_error(vchiq_susp_log_level,
1621                         "%s vchiq_initialise failed %d", __func__, status);
1622                 goto exit;
1623         }
1624
1625         status = vchiq_connect(instance);
1626         if (status != VCHIQ_SUCCESS) {
1627                 vchiq_log_error(vchiq_susp_log_level,
1628                         "%s vchiq_connect failed %d", __func__, status);
1629                 goto shutdown;
1630         }
1631
1632         status = vchiq_add_service(instance, &params, &ka_handle);
1633         if (status != VCHIQ_SUCCESS) {
1634                 vchiq_log_error(vchiq_susp_log_level,
1635                         "%s vchiq_open_service failed %d", __func__, status);
1636                 goto shutdown;
1637         }
1638
1639         while (1) {
1640                 long rc = 0, uc = 0;
1641                 if (wait_for_completion_interruptible(&arm_state->ka_evt)
1642                                 != 0) {
1643                         vchiq_log_error(vchiq_susp_log_level,
1644                                 "%s interrupted", __func__);
1645                         flush_signals(current);
1646                         continue;
1647                 }
1648
1649                 /* read and clear counters.  Do release_count then use_count to
1650                  * prevent getting more releases than uses */
1651                 rc = atomic_xchg(&arm_state->ka_release_count, 0);
1652                 uc = atomic_xchg(&arm_state->ka_use_count, 0);
1653
1654                 /* Call use/release service the requisite number of times.
1655                  * Process use before release so use counts don't go negative */
1656                 while (uc--) {
1657                         atomic_inc(&arm_state->ka_use_ack_count);
1658                         status = vchiq_use_service(ka_handle);
1659                         if (status != VCHIQ_SUCCESS) {
1660                                 vchiq_log_error(vchiq_susp_log_level,
1661                                         "%s vchiq_use_service error %d",
1662                                         __func__, status);
1663                         }
1664                 }
1665                 while (rc--) {
1666                         status = vchiq_release_service(ka_handle);
1667                         if (status != VCHIQ_SUCCESS) {
1668                                 vchiq_log_error(vchiq_susp_log_level,
1669                                         "%s vchiq_release_service error %d",
1670                                         __func__, status);
1671                         }
1672                 }
1673         }
1674
1675 shutdown:
1676         vchiq_shutdown(instance);
1677 exit:
1678         return 0;
1679 }
1680
1681
1682
1683 VCHIQ_STATUS_T
1684 vchiq_arm_init_state(VCHIQ_STATE_T *state, VCHIQ_ARM_STATE_T *arm_state)
1685 {
1686         VCHIQ_STATUS_T status = VCHIQ_SUCCESS;
1687
1688         if (arm_state) {
1689                 rwlock_init(&arm_state->susp_res_lock);
1690
1691                 init_completion(&arm_state->ka_evt);
1692                 atomic_set(&arm_state->ka_use_count, 0);
1693                 atomic_set(&arm_state->ka_use_ack_count, 0);
1694                 atomic_set(&arm_state->ka_release_count, 0);
1695
1696                 init_completion(&arm_state->vc_suspend_complete);
1697
1698                 init_completion(&arm_state->vc_resume_complete);
1699                 /* Initialise to 'done' state.  We only want to block on resume
1700                  * completion while videocore is suspended. */
1701                 set_resume_state(arm_state, VC_RESUME_RESUMED);
1702
1703                 init_completion(&arm_state->resume_blocker);
1704                 /* Initialise to 'done' state.  We only want to block on this
1705                  * completion while resume is blocked */
1706                 complete_all(&arm_state->resume_blocker);
1707
1708                 init_completion(&arm_state->blocked_blocker);
1709                 /* Initialise to 'done' state.  We only want to block on this
1710                  * completion while things are waiting on the resume blocker */
1711                 complete_all(&arm_state->blocked_blocker);
1712
1713                 arm_state->suspend_timer_timeout = SUSPEND_TIMER_TIMEOUT_MS;
1714                 arm_state->suspend_timer_running = 0;
1715                 init_timer(&arm_state->suspend_timer);
1716                 arm_state->suspend_timer.data = (unsigned long)(state);
1717                 arm_state->suspend_timer.function = suspend_timer_callback;
1718
1719                 arm_state->first_connect = 0;
1720
1721         }
1722         return status;
1723 }
1724
1725 /*
1726 ** Functions to modify the state variables;
1727 **      set_suspend_state
1728 **      set_resume_state
1729 **
1730 ** There are more state variables than we might like, so ensure they remain in
1731 ** step.  Suspend and resume state are maintained separately, since most of
1732 ** these state machines can operate independently.  However, there are a few
1733 ** states where state transitions in one state machine cause a reset to the
1734 ** other state machine.  In addition, there are some completion events which
1735 ** need to occur on state machine reset and end-state(s), so these are also
1736 ** dealt with in these functions.
1737 **
1738 ** In all states we set the state variable according to the input, but in some
1739 ** cases we perform additional steps outlined below;
1740 **
1741 ** VC_SUSPEND_IDLE - Initialise the suspend completion at the same time.
1742 **                      The suspend completion is completed after any suspend
1743 **                      attempt.  When we reset the state machine we also reset
1744 **                      the completion.  This reset occurs when videocore is
1745 **                      resumed, and also if we initiate suspend after a suspend
1746 **                      failure.
1747 **
1748 ** VC_SUSPEND_IN_PROGRESS - This state is considered the point of no return for
1749 **                      suspend - ie from this point on we must try to suspend
1750 **                      before resuming can occur.  We therefore also reset the
1751 **                      resume state machine to VC_RESUME_IDLE in this state.
1752 **
1753 ** VC_SUSPEND_SUSPENDED - Suspend has completed successfully. Also call
1754 **                      complete_all on the suspend completion to notify
1755 **                      anything waiting for suspend to happen.
1756 **
1757 ** VC_SUSPEND_REJECTED - Videocore rejected suspend. Videocore will also
1758 **                      initiate resume, so no need to alter resume state.
1759 **                      We call complete_all on the suspend completion to notify
1760 **                      of suspend rejection.
1761 **
1762 ** VC_SUSPEND_FAILED - We failed to initiate videocore suspend.  We notify the
1763 **                      suspend completion and reset the resume state machine.
1764 **
1765 ** VC_RESUME_IDLE - Initialise the resume completion at the same time.  The
1766 **                      resume completion is in it's 'done' state whenever
1767 **                      videcore is running.  Therfore, the VC_RESUME_IDLE state
1768 **                      implies that videocore is suspended.
1769 **                      Hence, any thread which needs to wait until videocore is
1770 **                      running can wait on this completion - it will only block
1771 **                      if videocore is suspended.
1772 **
1773 ** VC_RESUME_RESUMED - Resume has completed successfully.  Videocore is running.
1774 **                      Call complete_all on the resume completion to unblock
1775 **                      any threads waiting for resume.  Also reset the suspend
1776 **                      state machine to it's idle state.
1777 **
1778 ** VC_RESUME_FAILED - Currently unused - no mechanism to fail resume exists.
1779 */
1780
1781 void
1782 set_suspend_state(VCHIQ_ARM_STATE_T *arm_state,
1783         enum vc_suspend_status new_state)
1784 {
1785         /* set the state in all cases */
1786         arm_state->vc_suspend_state = new_state;
1787
1788         /* state specific additional actions */
1789         switch (new_state) {
1790         case VC_SUSPEND_FORCE_CANCELED:
1791                 complete_all(&arm_state->vc_suspend_complete);
1792                 break;
1793         case VC_SUSPEND_REJECTED:
1794                 complete_all(&arm_state->vc_suspend_complete);
1795                 break;
1796         case VC_SUSPEND_FAILED:
1797                 complete_all(&arm_state->vc_suspend_complete);
1798                 arm_state->vc_resume_state = VC_RESUME_RESUMED;
1799                 complete_all(&arm_state->vc_resume_complete);
1800                 break;
1801         case VC_SUSPEND_IDLE:
1802                 reinit_completion(&arm_state->vc_suspend_complete);
1803                 break;
1804         case VC_SUSPEND_REQUESTED:
1805                 break;
1806         case VC_SUSPEND_IN_PROGRESS:
1807                 set_resume_state(arm_state, VC_RESUME_IDLE);
1808                 break;
1809         case VC_SUSPEND_SUSPENDED:
1810                 complete_all(&arm_state->vc_suspend_complete);
1811                 break;
1812         default:
1813                 BUG();
1814                 break;
1815         }
1816 }
1817
1818 void
1819 set_resume_state(VCHIQ_ARM_STATE_T *arm_state,
1820         enum vc_resume_status new_state)
1821 {
1822         /* set the state in all cases */
1823         arm_state->vc_resume_state = new_state;
1824
1825         /* state specific additional actions */
1826         switch (new_state) {
1827         case VC_RESUME_FAILED:
1828                 break;
1829         case VC_RESUME_IDLE:
1830                 reinit_completion(&arm_state->vc_resume_complete);
1831                 break;
1832         case VC_RESUME_REQUESTED:
1833                 break;
1834         case VC_RESUME_IN_PROGRESS:
1835                 break;
1836         case VC_RESUME_RESUMED:
1837                 complete_all(&arm_state->vc_resume_complete);
1838                 set_suspend_state(arm_state, VC_SUSPEND_IDLE);
1839                 break;
1840         default:
1841                 BUG();
1842                 break;
1843         }
1844 }
1845
1846
1847 /* should be called with the write lock held */
1848 inline void
1849 start_suspend_timer(VCHIQ_ARM_STATE_T *arm_state)
1850 {
1851         del_timer(&arm_state->suspend_timer);
1852         arm_state->suspend_timer.expires = jiffies +
1853                 msecs_to_jiffies(arm_state->
1854                         suspend_timer_timeout);
1855         add_timer(&arm_state->suspend_timer);
1856         arm_state->suspend_timer_running = 1;
1857 }
1858
1859 /* should be called with the write lock held */
1860 static inline void
1861 stop_suspend_timer(VCHIQ_ARM_STATE_T *arm_state)
1862 {
1863         if (arm_state->suspend_timer_running) {
1864                 del_timer(&arm_state->suspend_timer);
1865                 arm_state->suspend_timer_running = 0;
1866         }
1867 }
1868
1869 static inline int
1870 need_resume(VCHIQ_STATE_T *state)
1871 {
1872         VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
1873         return (arm_state->vc_suspend_state > VC_SUSPEND_IDLE) &&
1874                         (arm_state->vc_resume_state < VC_RESUME_REQUESTED) &&
1875                         vchiq_videocore_wanted(state);
1876 }
1877
1878 static int
1879 block_resume(VCHIQ_ARM_STATE_T *arm_state)
1880 {
1881         int status = VCHIQ_SUCCESS;
1882         const unsigned long timeout_val =
1883                                 msecs_to_jiffies(FORCE_SUSPEND_TIMEOUT_MS);
1884         int resume_count = 0;
1885
1886         /* Allow any threads which were blocked by the last force suspend to
1887          * complete if they haven't already.  Only give this one shot; if
1888          * blocked_count is incremented after blocked_blocker is completed
1889          * (which only happens when blocked_count hits 0) then those threads
1890          * will have to wait until next time around */
1891         if (arm_state->blocked_count) {
1892                 reinit_completion(&arm_state->blocked_blocker);
1893                 write_unlock_bh(&arm_state->susp_res_lock);
1894                 vchiq_log_info(vchiq_susp_log_level, "%s wait for previously "
1895                         "blocked clients", __func__);
1896                 if (wait_for_completion_interruptible_timeout(
1897                                 &arm_state->blocked_blocker, timeout_val)
1898                                         <= 0) {
1899                         vchiq_log_error(vchiq_susp_log_level, "%s wait for "
1900                                 "previously blocked clients failed" , __func__);
1901                         status = VCHIQ_ERROR;
1902                         write_lock_bh(&arm_state->susp_res_lock);
1903                         goto out;
1904                 }
1905                 vchiq_log_info(vchiq_susp_log_level, "%s previously blocked "
1906                         "clients resumed", __func__);
1907                 write_lock_bh(&arm_state->susp_res_lock);
1908         }
1909
1910         /* We need to wait for resume to complete if it's in process */
1911         while (arm_state->vc_resume_state != VC_RESUME_RESUMED &&
1912                         arm_state->vc_resume_state > VC_RESUME_IDLE) {
1913                 if (resume_count > 1) {
1914                         status = VCHIQ_ERROR;
1915                         vchiq_log_error(vchiq_susp_log_level, "%s waited too "
1916                                 "many times for resume" , __func__);
1917                         goto out;
1918                 }
1919                 write_unlock_bh(&arm_state->susp_res_lock);
1920                 vchiq_log_info(vchiq_susp_log_level, "%s wait for resume",
1921                         __func__);
1922                 if (wait_for_completion_interruptible_timeout(
1923                                 &arm_state->vc_resume_complete, timeout_val)
1924                                         <= 0) {
1925                         vchiq_log_error(vchiq_susp_log_level, "%s wait for "
1926                                 "resume failed (%s)", __func__,
1927                                 resume_state_names[arm_state->vc_resume_state +
1928                                                         VC_RESUME_NUM_OFFSET]);
1929                         status = VCHIQ_ERROR;
1930                         write_lock_bh(&arm_state->susp_res_lock);
1931                         goto out;
1932                 }
1933                 vchiq_log_info(vchiq_susp_log_level, "%s resumed", __func__);
1934                 write_lock_bh(&arm_state->susp_res_lock);
1935                 resume_count++;
1936         }
1937         reinit_completion(&arm_state->resume_blocker);
1938         arm_state->resume_blocked = 1;
1939
1940 out:
1941         return status;
1942 }
1943
1944 static inline void
1945 unblock_resume(VCHIQ_ARM_STATE_T *arm_state)
1946 {
1947         complete_all(&arm_state->resume_blocker);
1948         arm_state->resume_blocked = 0;
1949 }
1950
1951 /* Initiate suspend via slot handler. Should be called with the write lock
1952  * held */
1953 VCHIQ_STATUS_T
1954 vchiq_arm_vcsuspend(VCHIQ_STATE_T *state)
1955 {
1956         VCHIQ_STATUS_T status = VCHIQ_ERROR;
1957         VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
1958
1959         if (!arm_state)
1960                 goto out;
1961
1962         vchiq_log_trace(vchiq_susp_log_level, "%s", __func__);
1963         status = VCHIQ_SUCCESS;
1964
1965
1966         switch (arm_state->vc_suspend_state) {
1967         case VC_SUSPEND_REQUESTED:
1968                 vchiq_log_info(vchiq_susp_log_level, "%s: suspend already "
1969                         "requested", __func__);
1970                 break;
1971         case VC_SUSPEND_IN_PROGRESS:
1972                 vchiq_log_info(vchiq_susp_log_level, "%s: suspend already in "
1973                         "progress", __func__);
1974                 break;
1975
1976         default:
1977                 /* We don't expect to be in other states, so log but continue
1978                  * anyway */
1979                 vchiq_log_error(vchiq_susp_log_level,
1980                         "%s unexpected suspend state %s", __func__,
1981                         suspend_state_names[arm_state->vc_suspend_state +
1982                                                 VC_SUSPEND_NUM_OFFSET]);
1983                 /* fall through */
1984         case VC_SUSPEND_REJECTED:
1985         case VC_SUSPEND_FAILED:
1986                 /* Ensure any idle state actions have been run */
1987                 set_suspend_state(arm_state, VC_SUSPEND_IDLE);
1988                 /* fall through */
1989         case VC_SUSPEND_IDLE:
1990                 vchiq_log_info(vchiq_susp_log_level,
1991                         "%s: suspending", __func__);
1992                 set_suspend_state(arm_state, VC_SUSPEND_REQUESTED);
1993                 /* kick the slot handler thread to initiate suspend */
1994                 request_poll(state, NULL, 0);
1995                 break;
1996         }
1997
1998 out:
1999         vchiq_log_trace(vchiq_susp_log_level, "%s exit %d", __func__, status);
2000         return status;
2001 }
2002
2003 void
2004 vchiq_platform_check_suspend(VCHIQ_STATE_T *state)
2005 {
2006         VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
2007         int susp = 0;
2008
2009         if (!arm_state)
2010                 goto out;
2011
2012         vchiq_log_trace(vchiq_susp_log_level, "%s", __func__);
2013
2014         write_lock_bh(&arm_state->susp_res_lock);
2015         if (arm_state->vc_suspend_state == VC_SUSPEND_REQUESTED &&
2016                         arm_state->vc_resume_state == VC_RESUME_RESUMED) {
2017                 set_suspend_state(arm_state, VC_SUSPEND_IN_PROGRESS);
2018                 susp = 1;
2019         }
2020         write_unlock_bh(&arm_state->susp_res_lock);
2021
2022         if (susp)
2023                 vchiq_platform_suspend(state);
2024
2025 out:
2026         vchiq_log_trace(vchiq_susp_log_level, "%s exit", __func__);
2027         return;
2028 }
2029
2030
2031 static void
2032 output_timeout_error(VCHIQ_STATE_T *state)
2033 {
2034         VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
2035         char service_err[50] = "";
2036         int vc_use_count = arm_state->videocore_use_count;
2037         int active_services = state->unused_service;
2038         int i;
2039
2040         if (!arm_state->videocore_use_count) {
2041                 snprintf(service_err, 50, " Videocore usecount is 0");
2042                 goto output_msg;
2043         }
2044         for (i = 0; i < active_services; i++) {
2045                 VCHIQ_SERVICE_T *service_ptr = state->services[i];
2046                 if (service_ptr && service_ptr->service_use_count &&
2047                         (service_ptr->srvstate != VCHIQ_SRVSTATE_FREE)) {
2048                         snprintf(service_err, 50, " %c%c%c%c(%d) service has "
2049                                 "use count %d%s", VCHIQ_FOURCC_AS_4CHARS(
2050                                         service_ptr->base.fourcc),
2051                                  service_ptr->client_id,
2052                                  service_ptr->service_use_count,
2053                                  service_ptr->service_use_count ==
2054                                          vc_use_count ? "" : " (+ more)");
2055                         break;
2056                 }
2057         }
2058
2059 output_msg:
2060         vchiq_log_error(vchiq_susp_log_level,
2061                 "timed out waiting for vc suspend (%d).%s",
2062                  arm_state->autosuspend_override, service_err);
2063
2064 }
2065
2066 /* Try to get videocore into suspended state, regardless of autosuspend state.
2067 ** We don't actually force suspend, since videocore may get into a bad state
2068 ** if we force suspend at a bad time.  Instead, we wait for autosuspend to
2069 ** determine a good point to suspend.  If this doesn't happen within 100ms we
2070 ** report failure.
2071 **
2072 ** Returns VCHIQ_SUCCESS if videocore suspended successfully, VCHIQ_RETRY if
2073 ** videocore failed to suspend in time or VCHIQ_ERROR if interrupted.
2074 */
2075 VCHIQ_STATUS_T
2076 vchiq_arm_force_suspend(VCHIQ_STATE_T *state)
2077 {
2078         VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
2079         VCHIQ_STATUS_T status = VCHIQ_ERROR;
2080         long rc = 0;
2081         int repeat = -1;
2082
2083         if (!arm_state)
2084                 goto out;
2085
2086         vchiq_log_trace(vchiq_susp_log_level, "%s", __func__);
2087
2088         write_lock_bh(&arm_state->susp_res_lock);
2089
2090         status = block_resume(arm_state);
2091         if (status != VCHIQ_SUCCESS)
2092                 goto unlock;
2093         if (arm_state->vc_suspend_state == VC_SUSPEND_SUSPENDED) {
2094                 /* Already suspended - just block resume and exit */
2095                 vchiq_log_info(vchiq_susp_log_level, "%s already suspended",
2096                         __func__);
2097                 status = VCHIQ_SUCCESS;
2098                 goto unlock;
2099         } else if (arm_state->vc_suspend_state <= VC_SUSPEND_IDLE) {
2100                 /* initiate suspend immediately in the case that we're waiting
2101                  * for the timeout */
2102                 stop_suspend_timer(arm_state);
2103                 if (!vchiq_videocore_wanted(state)) {
2104                         vchiq_log_info(vchiq_susp_log_level, "%s videocore "
2105                                 "idle, initiating suspend", __func__);
2106                         status = vchiq_arm_vcsuspend(state);
2107                 } else if (arm_state->autosuspend_override <
2108                                                 FORCE_SUSPEND_FAIL_MAX) {
2109                         vchiq_log_info(vchiq_susp_log_level, "%s letting "
2110                                 "videocore go idle", __func__);
2111                         status = VCHIQ_SUCCESS;
2112                 } else {
2113                         vchiq_log_warning(vchiq_susp_log_level, "%s failed too "
2114                                 "many times - attempting suspend", __func__);
2115                         status = vchiq_arm_vcsuspend(state);
2116                 }
2117         } else {
2118                 vchiq_log_info(vchiq_susp_log_level, "%s videocore suspend "
2119                         "in progress - wait for completion", __func__);
2120                 status = VCHIQ_SUCCESS;
2121         }
2122
2123         /* Wait for suspend to happen due to system idle (not forced..) */
2124         if (status != VCHIQ_SUCCESS)
2125                 goto unblock_resume;
2126
2127         do {
2128                 write_unlock_bh(&arm_state->susp_res_lock);
2129
2130                 rc = wait_for_completion_interruptible_timeout(
2131                                 &arm_state->vc_suspend_complete,
2132                                 msecs_to_jiffies(FORCE_SUSPEND_TIMEOUT_MS));
2133
2134                 write_lock_bh(&arm_state->susp_res_lock);
2135                 if (rc < 0) {
2136                         vchiq_log_warning(vchiq_susp_log_level, "%s "
2137                                 "interrupted waiting for suspend", __func__);
2138                         status = VCHIQ_ERROR;
2139                         goto unblock_resume;
2140                 } else if (rc == 0) {
2141                         if (arm_state->vc_suspend_state > VC_SUSPEND_IDLE) {
2142                                 /* Repeat timeout once if in progress */
2143                                 if (repeat < 0) {
2144                                         repeat = 1;
2145                                         continue;
2146                                 }
2147                         }
2148                         arm_state->autosuspend_override++;
2149                         output_timeout_error(state);
2150
2151                         status = VCHIQ_RETRY;
2152                         goto unblock_resume;
2153                 }
2154         } while (0 < (repeat--));
2155
2156         /* Check and report state in case we need to abort ARM suspend */
2157         if (arm_state->vc_suspend_state != VC_SUSPEND_SUSPENDED) {
2158                 status = VCHIQ_RETRY;
2159                 vchiq_log_error(vchiq_susp_log_level,
2160                         "%s videocore suspend failed (state %s)", __func__,
2161                         suspend_state_names[arm_state->vc_suspend_state +
2162                                                 VC_SUSPEND_NUM_OFFSET]);
2163                 /* Reset the state only if it's still in an error state.
2164                  * Something could have already initiated another suspend. */
2165                 if (arm_state->vc_suspend_state < VC_SUSPEND_IDLE)
2166                         set_suspend_state(arm_state, VC_SUSPEND_IDLE);
2167
2168                 goto unblock_resume;
2169         }
2170
2171         /* successfully suspended - unlock and exit */
2172         goto unlock;
2173
2174 unblock_resume:
2175         /* all error states need to unblock resume before exit */
2176         unblock_resume(arm_state);
2177
2178 unlock:
2179         write_unlock_bh(&arm_state->susp_res_lock);
2180
2181 out:
2182         vchiq_log_trace(vchiq_susp_log_level, "%s exit %d", __func__, status);
2183         return status;
2184 }
2185
2186 void
2187 vchiq_check_suspend(VCHIQ_STATE_T *state)
2188 {
2189         VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
2190
2191         if (!arm_state)
2192                 goto out;
2193
2194         vchiq_log_trace(vchiq_susp_log_level, "%s", __func__);
2195
2196         write_lock_bh(&arm_state->susp_res_lock);
2197         if (arm_state->vc_suspend_state != VC_SUSPEND_SUSPENDED &&
2198                         arm_state->first_connect &&
2199                         !vchiq_videocore_wanted(state)) {
2200                 vchiq_arm_vcsuspend(state);
2201         }
2202         write_unlock_bh(&arm_state->susp_res_lock);
2203
2204 out:
2205         vchiq_log_trace(vchiq_susp_log_level, "%s exit", __func__);
2206         return;
2207 }
2208
2209
2210 int
2211 vchiq_arm_allow_resume(VCHIQ_STATE_T *state)
2212 {
2213         VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
2214         int resume = 0;
2215         int ret = -1;
2216
2217         if (!arm_state)
2218                 goto out;
2219
2220         vchiq_log_trace(vchiq_susp_log_level, "%s", __func__);
2221
2222         write_lock_bh(&arm_state->susp_res_lock);
2223         unblock_resume(arm_state);
2224         resume = vchiq_check_resume(state);
2225         write_unlock_bh(&arm_state->susp_res_lock);
2226
2227         if (resume) {
2228                 if (wait_for_completion_interruptible(
2229                         &arm_state->vc_resume_complete) < 0) {
2230                         vchiq_log_error(vchiq_susp_log_level,
2231                                 "%s interrupted", __func__);
2232                         /* failed, cannot accurately derive suspend
2233                          * state, so exit early. */
2234                         goto out;
2235                 }
2236         }
2237
2238         read_lock_bh(&arm_state->susp_res_lock);
2239         if (arm_state->vc_suspend_state == VC_SUSPEND_SUSPENDED) {
2240                 vchiq_log_info(vchiq_susp_log_level,
2241                                 "%s: Videocore remains suspended", __func__);
2242         } else {
2243                 vchiq_log_info(vchiq_susp_log_level,
2244                                 "%s: Videocore resumed", __func__);
2245                 ret = 0;
2246         }
2247         read_unlock_bh(&arm_state->susp_res_lock);
2248 out:
2249         vchiq_log_trace(vchiq_susp_log_level, "%s exit %d", __func__, ret);
2250         return ret;
2251 }
2252
2253 /* This function should be called with the write lock held */
2254 int
2255 vchiq_check_resume(VCHIQ_STATE_T *state)
2256 {
2257         VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
2258         int resume = 0;
2259
2260         if (!arm_state)
2261                 goto out;
2262
2263         vchiq_log_trace(vchiq_susp_log_level, "%s", __func__);
2264
2265         if (need_resume(state)) {
2266                 set_resume_state(arm_state, VC_RESUME_REQUESTED);
2267                 request_poll(state, NULL, 0);
2268                 resume = 1;
2269         }
2270
2271 out:
2272         vchiq_log_trace(vchiq_susp_log_level, "%s exit", __func__);
2273         return resume;
2274 }
2275
2276 void
2277 vchiq_platform_check_resume(VCHIQ_STATE_T *state)
2278 {
2279         VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
2280         int res = 0;
2281
2282         if (!arm_state)
2283                 goto out;
2284
2285         vchiq_log_trace(vchiq_susp_log_level, "%s", __func__);
2286
2287         write_lock_bh(&arm_state->susp_res_lock);
2288         if (arm_state->wake_address == 0) {
2289                 vchiq_log_info(vchiq_susp_log_level,
2290                                         "%s: already awake", __func__);
2291                 goto unlock;
2292         }
2293         if (arm_state->vc_resume_state == VC_RESUME_IN_PROGRESS) {
2294                 vchiq_log_info(vchiq_susp_log_level,
2295                                         "%s: already resuming", __func__);
2296                 goto unlock;
2297         }
2298
2299         if (arm_state->vc_resume_state == VC_RESUME_REQUESTED) {
2300                 set_resume_state(arm_state, VC_RESUME_IN_PROGRESS);
2301                 res = 1;
2302         } else
2303                 vchiq_log_trace(vchiq_susp_log_level,
2304                                 "%s: not resuming (resume state %s)", __func__,
2305                                 resume_state_names[arm_state->vc_resume_state +
2306                                                         VC_RESUME_NUM_OFFSET]);
2307
2308 unlock:
2309         write_unlock_bh(&arm_state->susp_res_lock);
2310
2311         if (res)
2312                 vchiq_platform_resume(state);
2313
2314 out:
2315         vchiq_log_trace(vchiq_susp_log_level, "%s exit", __func__);
2316         return;
2317
2318 }
2319
2320
2321
2322 VCHIQ_STATUS_T
2323 vchiq_use_internal(VCHIQ_STATE_T *state, VCHIQ_SERVICE_T *service,
2324                 enum USE_TYPE_E use_type)
2325 {
2326         VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
2327         VCHIQ_STATUS_T ret = VCHIQ_SUCCESS;
2328         char entity[16];
2329         int *entity_uc;
2330         int local_uc, local_entity_uc;
2331
2332         if (!arm_state)
2333                 goto out;
2334
2335         vchiq_log_trace(vchiq_susp_log_level, "%s", __func__);
2336
2337         if (use_type == USE_TYPE_VCHIQ) {
2338                 sprintf(entity, "VCHIQ:   ");
2339                 entity_uc = &arm_state->peer_use_count;
2340         } else if (service) {
2341                 sprintf(entity, "%c%c%c%c:%03d",
2342                         VCHIQ_FOURCC_AS_4CHARS(service->base.fourcc),
2343                         service->client_id);
2344                 entity_uc = &service->service_use_count;
2345         } else {
2346                 vchiq_log_error(vchiq_susp_log_level, "%s null service "
2347                                 "ptr", __func__);
2348                 ret = VCHIQ_ERROR;
2349                 goto out;
2350         }
2351
2352         write_lock_bh(&arm_state->susp_res_lock);
2353         while (arm_state->resume_blocked) {
2354                 /* If we call 'use' while force suspend is waiting for suspend,
2355                  * then we're about to block the thread which the force is
2356                  * waiting to complete, so we're bound to just time out. In this
2357                  * case, set the suspend state such that the wait will be
2358                  * canceled, so we can complete as quickly as possible. */
2359                 if (arm_state->resume_blocked && arm_state->vc_suspend_state ==
2360                                 VC_SUSPEND_IDLE) {
2361                         set_suspend_state(arm_state, VC_SUSPEND_FORCE_CANCELED);
2362                         break;
2363                 }
2364                 /* If suspend is already in progress then we need to block */
2365                 if (!try_wait_for_completion(&arm_state->resume_blocker)) {
2366                         /* Indicate that there are threads waiting on the resume
2367                          * blocker.  These need to be allowed to complete before
2368                          * a _second_ call to force suspend can complete,
2369                          * otherwise low priority threads might never actually
2370                          * continue */
2371                         arm_state->blocked_count++;
2372                         write_unlock_bh(&arm_state->susp_res_lock);
2373                         vchiq_log_info(vchiq_susp_log_level, "%s %s resume "
2374                                 "blocked - waiting...", __func__, entity);
2375                         if (wait_for_completion_killable(
2376                                         &arm_state->resume_blocker) != 0) {
2377                                 vchiq_log_error(vchiq_susp_log_level, "%s %s "
2378                                         "wait for resume blocker interrupted",
2379                                         __func__, entity);
2380                                 ret = VCHIQ_ERROR;
2381                                 write_lock_bh(&arm_state->susp_res_lock);
2382                                 arm_state->blocked_count--;
2383                                 write_unlock_bh(&arm_state->susp_res_lock);
2384                                 goto out;
2385                         }
2386                         vchiq_log_info(vchiq_susp_log_level, "%s %s resume "
2387                                 "unblocked", __func__, entity);
2388                         write_lock_bh(&arm_state->susp_res_lock);
2389                         if (--arm_state->blocked_count == 0)
2390                                 complete_all(&arm_state->blocked_blocker);
2391                 }
2392         }
2393
2394         stop_suspend_timer(arm_state);
2395
2396         local_uc = ++arm_state->videocore_use_count;
2397         local_entity_uc = ++(*entity_uc);
2398
2399         /* If there's a pending request which hasn't yet been serviced then
2400          * just clear it.  If we're past VC_SUSPEND_REQUESTED state then
2401          * vc_resume_complete will block until we either resume or fail to
2402          * suspend */
2403         if (arm_state->vc_suspend_state <= VC_SUSPEND_REQUESTED)
2404                 set_suspend_state(arm_state, VC_SUSPEND_IDLE);
2405
2406         if ((use_type != USE_TYPE_SERVICE_NO_RESUME) && need_resume(state)) {
2407                 set_resume_state(arm_state, VC_RESUME_REQUESTED);
2408                 vchiq_log_info(vchiq_susp_log_level,
2409                         "%s %s count %d, state count %d",
2410                         __func__, entity, local_entity_uc, local_uc);
2411                 request_poll(state, NULL, 0);
2412         } else
2413                 vchiq_log_trace(vchiq_susp_log_level,
2414                         "%s %s count %d, state count %d",
2415                         __func__, entity, *entity_uc, local_uc);
2416
2417
2418         write_unlock_bh(&arm_state->susp_res_lock);
2419
2420         /* Completion is in a done state when we're not suspended, so this won't
2421          * block for the non-suspended case. */
2422         if (!try_wait_for_completion(&arm_state->vc_resume_complete)) {
2423                 vchiq_log_info(vchiq_susp_log_level, "%s %s wait for resume",
2424                         __func__, entity);
2425                 if (wait_for_completion_killable(
2426                                 &arm_state->vc_resume_complete) != 0) {
2427                         vchiq_log_error(vchiq_susp_log_level, "%s %s wait for "
2428                                 "resume interrupted", __func__, entity);
2429                         ret = VCHIQ_ERROR;
2430                         goto out;
2431                 }
2432                 vchiq_log_info(vchiq_susp_log_level, "%s %s resumed", __func__,
2433                         entity);
2434         }
2435
2436         if (ret == VCHIQ_SUCCESS) {
2437                 VCHIQ_STATUS_T status = VCHIQ_SUCCESS;
2438                 long ack_cnt = atomic_xchg(&arm_state->ka_use_ack_count, 0);
2439                 while (ack_cnt && (status == VCHIQ_SUCCESS)) {
2440                         /* Send the use notify to videocore */
2441                         status = vchiq_send_remote_use_active(state);
2442                         if (status == VCHIQ_SUCCESS)
2443                                 ack_cnt--;
2444                         else
2445                                 atomic_add(ack_cnt,
2446                                         &arm_state->ka_use_ack_count);
2447                 }
2448         }
2449
2450 out:
2451         vchiq_log_trace(vchiq_susp_log_level, "%s exit %d", __func__, ret);
2452         return ret;
2453 }
2454
2455 VCHIQ_STATUS_T
2456 vchiq_release_internal(VCHIQ_STATE_T *state, VCHIQ_SERVICE_T *service)
2457 {
2458         VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
2459         VCHIQ_STATUS_T ret = VCHIQ_SUCCESS;
2460         char entity[16];
2461         int *entity_uc;
2462         int local_uc, local_entity_uc;
2463
2464         if (!arm_state)
2465                 goto out;
2466
2467         vchiq_log_trace(vchiq_susp_log_level, "%s", __func__);
2468
2469         if (service) {
2470                 sprintf(entity, "%c%c%c%c:%03d",
2471                         VCHIQ_FOURCC_AS_4CHARS(service->base.fourcc),
2472                         service->client_id);
2473                 entity_uc = &service->service_use_count;
2474         } else {
2475                 sprintf(entity, "PEER:   ");
2476                 entity_uc = &arm_state->peer_use_count;
2477         }
2478
2479         write_lock_bh(&arm_state->susp_res_lock);
2480         if (!arm_state->videocore_use_count || !(*entity_uc)) {
2481                 /* Don't use BUG_ON - don't allow user thread to crash kernel */
2482                 WARN_ON(!arm_state->videocore_use_count);
2483                 WARN_ON(!(*entity_uc));
2484                 ret = VCHIQ_ERROR;
2485                 goto unlock;
2486         }
2487         local_uc = --arm_state->videocore_use_count;
2488         local_entity_uc = --(*entity_uc);
2489
2490         if (!vchiq_videocore_wanted(state)) {
2491                 if (vchiq_platform_use_suspend_timer() &&
2492                                 !arm_state->resume_blocked) {
2493                         /* Only use the timer if we're not trying to force
2494                          * suspend (=> resume_blocked) */
2495                         start_suspend_timer(arm_state);
2496                 } else {
2497                         vchiq_log_info(vchiq_susp_log_level,
2498                                 "%s %s count %d, state count %d - suspending",
2499                                 __func__, entity, *entity_uc,
2500                                 arm_state->videocore_use_count);
2501                         vchiq_arm_vcsuspend(state);
2502                 }
2503         } else
2504                 vchiq_log_trace(vchiq_susp_log_level,
2505                         "%s %s count %d, state count %d",
2506                         __func__, entity, *entity_uc,
2507                         arm_state->videocore_use_count);
2508
2509 unlock:
2510         write_unlock_bh(&arm_state->susp_res_lock);
2511
2512 out:
2513         vchiq_log_trace(vchiq_susp_log_level, "%s exit %d", __func__, ret);
2514         return ret;
2515 }
2516
2517 void
2518 vchiq_on_remote_use(VCHIQ_STATE_T *state)
2519 {
2520         VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
2521         vchiq_log_trace(vchiq_susp_log_level, "%s", __func__);
2522         atomic_inc(&arm_state->ka_use_count);
2523         complete(&arm_state->ka_evt);
2524 }
2525
2526 void
2527 vchiq_on_remote_release(VCHIQ_STATE_T *state)
2528 {
2529         VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
2530         vchiq_log_trace(vchiq_susp_log_level, "%s", __func__);
2531         atomic_inc(&arm_state->ka_release_count);
2532         complete(&arm_state->ka_evt);
2533 }
2534
2535 VCHIQ_STATUS_T
2536 vchiq_use_service_internal(VCHIQ_SERVICE_T *service)
2537 {
2538         return vchiq_use_internal(service->state, service, USE_TYPE_SERVICE);
2539 }
2540
2541 VCHIQ_STATUS_T
2542 vchiq_release_service_internal(VCHIQ_SERVICE_T *service)
2543 {
2544         return vchiq_release_internal(service->state, service);
2545 }
2546
2547 VCHIQ_DEBUGFS_NODE_T *
2548 vchiq_instance_get_debugfs_node(VCHIQ_INSTANCE_T instance)
2549 {
2550         return &instance->debugfs_node;
2551 }
2552
2553 int
2554 vchiq_instance_get_use_count(VCHIQ_INSTANCE_T instance)
2555 {
2556         VCHIQ_SERVICE_T *service;
2557         int use_count = 0, i;
2558         i = 0;
2559         while ((service = next_service_by_instance(instance->state,
2560                 instance, &i)) != NULL) {
2561                 use_count += service->service_use_count;
2562                 unlock_service(service);
2563         }
2564         return use_count;
2565 }
2566
2567 int
2568 vchiq_instance_get_pid(VCHIQ_INSTANCE_T instance)
2569 {
2570         return instance->pid;
2571 }
2572
2573 int
2574 vchiq_instance_get_trace(VCHIQ_INSTANCE_T instance)
2575 {
2576         return instance->trace;
2577 }
2578
2579 void
2580 vchiq_instance_set_trace(VCHIQ_INSTANCE_T instance, int trace)
2581 {
2582         VCHIQ_SERVICE_T *service;
2583         int i;
2584         i = 0;
2585         while ((service = next_service_by_instance(instance->state,
2586                 instance, &i)) != NULL) {
2587                 service->trace = trace;
2588                 unlock_service(service);
2589         }
2590         instance->trace = (trace != 0);
2591 }
2592
2593 static void suspend_timer_callback(unsigned long context)
2594 {
2595         VCHIQ_STATE_T *state = (VCHIQ_STATE_T *)context;
2596         VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
2597         if (!arm_state)
2598                 goto out;
2599         vchiq_log_info(vchiq_susp_log_level,
2600                 "%s - suspend timer expired - check suspend", __func__);
2601         vchiq_check_suspend(state);
2602 out:
2603         return;
2604 }
2605
2606 VCHIQ_STATUS_T
2607 vchiq_use_service_no_resume(VCHIQ_SERVICE_HANDLE_T handle)
2608 {
2609         VCHIQ_STATUS_T ret = VCHIQ_ERROR;
2610         VCHIQ_SERVICE_T *service = find_service_by_handle(handle);
2611         if (service) {
2612                 ret = vchiq_use_internal(service->state, service,
2613                                 USE_TYPE_SERVICE_NO_RESUME);
2614                 unlock_service(service);
2615         }
2616         return ret;
2617 }
2618
2619 VCHIQ_STATUS_T
2620 vchiq_use_service(VCHIQ_SERVICE_HANDLE_T handle)
2621 {
2622         VCHIQ_STATUS_T ret = VCHIQ_ERROR;
2623         VCHIQ_SERVICE_T *service = find_service_by_handle(handle);
2624         if (service) {
2625                 ret = vchiq_use_internal(service->state, service,
2626                                 USE_TYPE_SERVICE);
2627                 unlock_service(service);
2628         }
2629         return ret;
2630 }
2631
2632 VCHIQ_STATUS_T
2633 vchiq_release_service(VCHIQ_SERVICE_HANDLE_T handle)
2634 {
2635         VCHIQ_STATUS_T ret = VCHIQ_ERROR;
2636         VCHIQ_SERVICE_T *service = find_service_by_handle(handle);
2637         if (service) {
2638                 ret = vchiq_release_internal(service->state, service);
2639                 unlock_service(service);
2640         }
2641         return ret;
2642 }
2643
2644 void
2645 vchiq_dump_service_use_state(VCHIQ_STATE_T *state)
2646 {
2647         VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
2648         int i, j = 0;
2649         /* Only dump 64 services */
2650         static const int local_max_services = 64;
2651         /* If there's more than 64 services, only dump ones with
2652          * non-zero counts */
2653         int only_nonzero = 0;
2654         static const char *nz = "<-- preventing suspend";
2655
2656         enum vc_suspend_status vc_suspend_state;
2657         enum vc_resume_status  vc_resume_state;
2658         int peer_count;
2659         int vc_use_count;
2660         int active_services;
2661         struct service_data_struct {
2662                 int fourcc;
2663                 int clientid;
2664                 int use_count;
2665         } service_data[local_max_services];
2666
2667         if (!arm_state)
2668                 return;
2669
2670         read_lock_bh(&arm_state->susp_res_lock);
2671         vc_suspend_state = arm_state->vc_suspend_state;
2672         vc_resume_state  = arm_state->vc_resume_state;
2673         peer_count = arm_state->peer_use_count;
2674         vc_use_count = arm_state->videocore_use_count;
2675         active_services = state->unused_service;
2676         if (active_services > local_max_services)
2677                 only_nonzero = 1;
2678
2679         for (i = 0; (i < active_services) && (j < local_max_services); i++) {
2680                 VCHIQ_SERVICE_T *service_ptr = state->services[i];
2681                 if (!service_ptr)
2682                         continue;
2683
2684                 if (only_nonzero && !service_ptr->service_use_count)
2685                         continue;
2686
2687                 if (service_ptr->srvstate != VCHIQ_SRVSTATE_FREE) {
2688                         service_data[j].fourcc = service_ptr->base.fourcc;
2689                         service_data[j].clientid = service_ptr->client_id;
2690                         service_data[j++].use_count = service_ptr->
2691                                                         service_use_count;
2692                 }
2693         }
2694
2695         read_unlock_bh(&arm_state->susp_res_lock);
2696
2697         vchiq_log_warning(vchiq_susp_log_level,
2698                 "-- Videcore suspend state: %s --",
2699                 suspend_state_names[vc_suspend_state + VC_SUSPEND_NUM_OFFSET]);
2700         vchiq_log_warning(vchiq_susp_log_level,
2701                 "-- Videcore resume state: %s --",
2702                 resume_state_names[vc_resume_state + VC_RESUME_NUM_OFFSET]);
2703
2704         if (only_nonzero)
2705                 vchiq_log_warning(vchiq_susp_log_level, "Too many active "
2706                         "services (%d).  Only dumping up to first %d services "
2707                         "with non-zero use-count", active_services,
2708                         local_max_services);
2709
2710         for (i = 0; i < j; i++) {
2711                 vchiq_log_warning(vchiq_susp_log_level,
2712                         "----- %c%c%c%c:%d service count %d %s",
2713                         VCHIQ_FOURCC_AS_4CHARS(service_data[i].fourcc),
2714                         service_data[i].clientid,
2715                         service_data[i].use_count,
2716                         service_data[i].use_count ? nz : "");
2717         }
2718         vchiq_log_warning(vchiq_susp_log_level,
2719                 "----- VCHIQ use count count %d", peer_count);
2720         vchiq_log_warning(vchiq_susp_log_level,
2721                 "--- Overall vchiq instance use count %d", vc_use_count);
2722
2723         vchiq_dump_platform_use_state(state);
2724 }
2725
2726 VCHIQ_STATUS_T
2727 vchiq_check_service(VCHIQ_SERVICE_T *service)
2728 {
2729         VCHIQ_ARM_STATE_T *arm_state;
2730         VCHIQ_STATUS_T ret = VCHIQ_ERROR;
2731
2732         if (!service || !service->state)
2733                 goto out;
2734
2735         vchiq_log_trace(vchiq_susp_log_level, "%s", __func__);
2736
2737         arm_state = vchiq_platform_get_arm_state(service->state);
2738
2739         read_lock_bh(&arm_state->susp_res_lock);
2740         if (service->service_use_count)
2741                 ret = VCHIQ_SUCCESS;
2742         read_unlock_bh(&arm_state->susp_res_lock);
2743
2744         if (ret == VCHIQ_ERROR) {
2745                 vchiq_log_error(vchiq_susp_log_level,
2746                         "%s ERROR - %c%c%c%c:%d service count %d, "
2747                         "state count %d, videocore suspend state %s", __func__,
2748                         VCHIQ_FOURCC_AS_4CHARS(service->base.fourcc),
2749                         service->client_id, service->service_use_count,
2750                         arm_state->videocore_use_count,
2751                         suspend_state_names[arm_state->vc_suspend_state +
2752                                                 VC_SUSPEND_NUM_OFFSET]);
2753                 vchiq_dump_service_use_state(service->state);
2754         }
2755 out:
2756         return ret;
2757 }
2758
2759 /* stub functions */
2760 void vchiq_on_remote_use_active(VCHIQ_STATE_T *state)
2761 {
2762         (void)state;
2763 }
2764
2765 void vchiq_platform_conn_state_changed(VCHIQ_STATE_T *state,
2766         VCHIQ_CONNSTATE_T oldstate, VCHIQ_CONNSTATE_T newstate)
2767 {
2768         VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
2769         vchiq_log_info(vchiq_susp_log_level, "%d: %s->%s", state->id,
2770                 get_conn_state_name(oldstate), get_conn_state_name(newstate));
2771         if (state->conn_state == VCHIQ_CONNSTATE_CONNECTED) {
2772                 write_lock_bh(&arm_state->susp_res_lock);
2773                 if (!arm_state->first_connect) {
2774                         char threadname[10];
2775                         arm_state->first_connect = 1;
2776                         write_unlock_bh(&arm_state->susp_res_lock);
2777                         snprintf(threadname, sizeof(threadname), "VCHIQka-%d",
2778                                 state->id);
2779                         arm_state->ka_thread = kthread_create(
2780                                 &vchiq_keepalive_thread_func,
2781                                 (void *)state,
2782                                 threadname);
2783                         if (arm_state->ka_thread == NULL) {
2784                                 vchiq_log_error(vchiq_susp_log_level,
2785                                         "vchiq: FATAL: couldn't create thread %s",
2786                                         threadname);
2787                         } else {
2788                                 wake_up_process(arm_state->ka_thread);
2789                         }
2790                 } else
2791                         write_unlock_bh(&arm_state->susp_res_lock);
2792         }
2793 }
2794
2795 static int vchiq_probe(struct platform_device *pdev)
2796 {
2797         struct device_node *fw_node;
2798         struct rpi_firmware *fw;
2799         int err;
2800         void *ptr_err;
2801
2802         fw_node = of_parse_phandle(pdev->dev.of_node, "firmware", 0);
2803 /* Remove comment when booting without Device Tree is no longer supported
2804         if (!fw_node) {
2805                 dev_err(&pdev->dev, "Missing firmware node\n");
2806                 return -ENOENT;
2807         }
2808 */
2809         fw = rpi_firmware_get(fw_node);
2810         if (!fw)
2811                 return -EPROBE_DEFER;
2812
2813         platform_set_drvdata(pdev, fw);
2814
2815         /* create debugfs entries */
2816         err = vchiq_debugfs_init();
2817         if (err != 0)
2818                 goto failed_debugfs_init;
2819
2820         err = alloc_chrdev_region(&vchiq_devid, VCHIQ_MINOR, 1, DEVICE_NAME);
2821         if (err != 0) {
2822                 vchiq_log_error(vchiq_arm_log_level,
2823                         "Unable to allocate device number");
2824                 goto failed_alloc_chrdev;
2825         }
2826         cdev_init(&vchiq_cdev, &vchiq_fops);
2827         vchiq_cdev.owner = THIS_MODULE;
2828         err = cdev_add(&vchiq_cdev, vchiq_devid, 1);
2829         if (err != 0) {
2830                 vchiq_log_error(vchiq_arm_log_level,
2831                         "Unable to register device");
2832                 goto failed_cdev_add;
2833         }
2834
2835         /* create sysfs entries */
2836         vchiq_class = class_create(THIS_MODULE, DEVICE_NAME);
2837         ptr_err = vchiq_class;
2838         if (IS_ERR(ptr_err))
2839                 goto failed_class_create;
2840
2841         vchiq_dev = device_create(vchiq_class, NULL,
2842                 vchiq_devid, NULL, "vchiq");
2843         ptr_err = vchiq_dev;
2844         if (IS_ERR(ptr_err))
2845                 goto failed_device_create;
2846
2847         err = vchiq_platform_init(pdev, &g_state);
2848         if (err != 0)
2849                 goto failed_platform_init;
2850
2851         vchiq_log_info(vchiq_arm_log_level,
2852                 "vchiq: initialised - version %d (min %d), device %d.%d",
2853                 VCHIQ_VERSION, VCHIQ_VERSION_MIN,
2854                 MAJOR(vchiq_devid), MINOR(vchiq_devid));
2855
2856         return 0;
2857
2858 failed_platform_init:
2859         device_destroy(vchiq_class, vchiq_devid);
2860 failed_device_create:
2861         class_destroy(vchiq_class);
2862 failed_class_create:
2863         cdev_del(&vchiq_cdev);
2864         err = PTR_ERR(ptr_err);
2865 failed_cdev_add:
2866         unregister_chrdev_region(vchiq_devid, 1);
2867 failed_alloc_chrdev:
2868         vchiq_debugfs_deinit();
2869 failed_debugfs_init:
2870         vchiq_log_warning(vchiq_arm_log_level, "could not load vchiq");
2871         return err;
2872 }
2873
2874 static int vchiq_remove(struct platform_device *pdev)
2875 {
2876         device_destroy(vchiq_class, vchiq_devid);
2877         class_destroy(vchiq_class);
2878         cdev_del(&vchiq_cdev);
2879         unregister_chrdev_region(vchiq_devid, 1);
2880
2881         return 0;
2882 }
2883
2884 static const struct of_device_id vchiq_of_match[] = {
2885         { .compatible = "brcm,bcm2835-vchiq", },
2886         {},
2887 };
2888 MODULE_DEVICE_TABLE(of, vchiq_of_match);
2889
2890 static struct platform_driver vchiq_driver = {
2891         .driver = {
2892                 .name = "bcm2835_vchiq",
2893                 .owner = THIS_MODULE,
2894                 .of_match_table = vchiq_of_match,
2895         },
2896         .probe = vchiq_probe,
2897         .remove = vchiq_remove,
2898 };
2899 module_platform_driver(vchiq_driver);
2900
2901 MODULE_LICENSE("GPL");
2902 MODULE_AUTHOR("Broadcom Corporation");