drivers/staging/greybus/svc.c

   1 /*
   2  * SVC Greybus driver.
   3  *
   4  * Copyright 2015 Google Inc.
   5  * Copyright 2015 Linaro Ltd.
   6  *
   7  * Released under the GPLv2 only.
   8  */
   9
  10 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  11 #include <linux/workqueue.h>
  12
  13 #include "greybus.h"
  14
  15 #define CPORT_FLAGS_E2EFC       BIT(0)
  16 #define CPORT_FLAGS_CSD_N       BIT(1)
  17 #define CPORT_FLAGS_CSV_N       BIT(2)
  18
  19 enum gb_svc_state {
  20         GB_SVC_STATE_RESET,
  21         GB_SVC_STATE_PROTOCOL_VERSION,
  22         GB_SVC_STATE_SVC_HELLO,
  23 };
  24
  25 struct gb_svc {
  26         struct gb_connection    *connection;
  27         enum gb_svc_state       state;
  28         struct ida              device_id_map;
  29 };
  30
  31 struct svc_hotplug {
  32         struct work_struct work;
  33         struct gb_connection *connection;
  34         struct gb_svc_intf_hotplug_request data;
  35 };
  36
  37
  38 /*
  39  * AP's SVC cport is required early to get messages from the SVC. This happens
  40  * even before the Endo is created and hence any modules or interfaces.
  41  *
  42  * This is a temporary connection, used only at initial bootup.
  43  */
  44 struct gb_connection *
  45 gb_ap_svc_connection_create(struct gb_host_device *hd)
  46 {
  47         struct gb_connection *connection;
  48
  49         connection = gb_connection_create_range(hd, NULL, &hd->dev,
  50                                                 GB_SVC_CPORT_ID,
  51                                                 GREYBUS_PROTOCOL_SVC,
  52                                                 GB_SVC_CPORT_ID,
  53                                                 GB_SVC_CPORT_ID + 1);
  54
  55         return connection;
  56 }
  57
  58 /*
  59  * We know endo-type and AP's interface id now, lets create a proper svc
  60  * connection (and its interface/bundle) now and get rid of the initial
  61  * 'partially' initialized one svc connection.
  62  */
  63 static struct gb_interface *
  64 gb_ap_interface_create(struct gb_host_device *hd,
  65                        struct gb_connection *connection, u8 interface_id)
  66 {
  67         struct gb_interface *intf;
  68         struct device *dev = &hd->endo->dev;
  69
  70         intf = gb_interface_create(hd, interface_id);
  71         if (!intf) {
  72                 dev_err(dev, "%s: Failed to create interface with id %hhu\n",
  73                         __func__, interface_id);
  74                 return NULL;
  75         }
  76
  77         intf->device_id = GB_DEVICE_ID_AP;
  78         svc_update_connection(intf, connection);
  79
  80         /* Its no longer a partially initialized connection */
  81         hd->initial_svc_connection = NULL;
  82
  83         return intf;
  84 }
  85
  86 static int gb_svc_intf_device_id(struct gb_svc *svc, u8 intf_id, u8 device_id)
  87 {
  88         struct gb_svc_intf_device_id_request request;
  89
  90         request.intf_id = intf_id;
  91         request.device_id = device_id;
  92
  93         return gb_operation_sync(svc->connection, GB_SVC_TYPE_INTF_DEVICE_ID,
  94                                  &request, sizeof(request), NULL, 0);
  95 }
  96
  97 int gb_svc_intf_reset(struct gb_svc *svc, u8 intf_id)
  98 {
  99         struct gb_svc_intf_reset_request request;
 100
 101         request.intf_id = intf_id;
 102
 103         return gb_operation_sync(svc->connection, GB_SVC_TYPE_INTF_RESET,
 104                                  &request, sizeof(request), NULL, 0);
 105 }
 106 EXPORT_SYMBOL_GPL(gb_svc_intf_reset);
 107
 108 int gb_svc_dme_peer_get(struct gb_svc *svc, u8 intf_id, u16 attr, u16 selector,
 109                         u32 *value)
 110 {
 111         struct gb_svc_dme_peer_get_request request;
 112         struct gb_svc_dme_peer_get_response response;
 113         u16 result;
 114         int ret;
 115
 116         request.intf_id = intf_id;
 117         request.attr = cpu_to_le16(attr);
 118         request.selector = cpu_to_le16(selector);
 119
 120         ret = gb_operation_sync(svc->connection, GB_SVC_TYPE_DME_PEER_GET,
 121                                 &request, sizeof(request),
 122                                 &response, sizeof(response));
 123         if (ret) {
 124                 pr_err("failed to get DME attribute (%hhu %hx %hu) %d\n",
 125                        intf_id, attr, selector, ret);
 126                 return ret;
 127         }
 128
 129         result = le16_to_cpu(response.result_code);
 130         if (result) {
 131                 pr_err("Unipro error %hu while getting DME attribute (%hhu %hx %hu)\n",
 132                        result, intf_id, attr, selector);
 133                 return -EINVAL;
 134         }
 135
 136         if (value)
 137                 *value = le32_to_cpu(response.attr_value);
 138
 139         return 0;
 140 }
 141 EXPORT_SYMBOL_GPL(gb_svc_dme_peer_get);
 142
 143 int gb_svc_dme_peer_set(struct gb_svc *svc, u8 intf_id, u16 attr, u16 selector,
 144                         u32 value)
 145 {
 146         struct gb_svc_dme_peer_set_request request;
 147         struct gb_svc_dme_peer_set_response response;
 148         u16 result;
 149         int ret;
 150
 151         request.intf_id = intf_id;
 152         request.attr = cpu_to_le16(attr);
 153         request.selector = cpu_to_le16(selector);
 154         request.value = cpu_to_le32(value);
 155
 156         ret = gb_operation_sync(svc->connection, GB_SVC_TYPE_DME_PEER_SET,
 157                                 &request, sizeof(request),
 158                                 &response, sizeof(response));
 159         if (ret) {
 160                 pr_err("failed to set DME attribute (%hhu %hx %hu %u) %d\n",
 161                        intf_id, attr, selector, value, ret);
 162                 return ret;
 163         }
 164
 165         result = le16_to_cpu(response.result_code);
 166         if (result) {
 167                 pr_err("Unipro error %hu while setting DME attribute (%hhu %hx %hu %u)\n",
 168                        result, intf_id, attr, selector, value);
 169                 return -EINVAL;
 170         }
 171
 172         return 0;
 173 }
 174 EXPORT_SYMBOL_GPL(gb_svc_dme_peer_set);
 175
 176 /*
 177  * T_TstSrcIncrement is written by the module on ES2 as a stand-in for boot
 178  * status attribute. AP needs to read and clear it, after reading a non-zero
 179  * value from it.
 180  *
 181  * FIXME: This is module-hardware dependent and needs to be extended for every
 182  * type of module we want to support.
 183  */
 184 static int gb_svc_read_and_clear_module_boot_status(struct gb_interface *intf)
 185 {
 186         struct gb_host_device *hd = intf->hd;
 187         int ret;
 188         u32 value;
 189
 190         /* Read and clear boot status in T_TstSrcIncrement */
 191         ret = gb_svc_dme_peer_get(hd->svc, intf->interface_id,
 192                                   DME_ATTR_T_TST_SRC_INCREMENT,
 193                                   DME_ATTR_SELECTOR_INDEX, &value);
 194
 195         if (ret)
 196                 return ret;
 197
 198         /*
 199          * A nonzero boot status indicates the module has finished
 200          * booting. Clear it.
 201          */
 202         if (!value) {
 203                 dev_err(&intf->dev, "Module not ready yet\n");
 204                 return -ENODEV;
 205         }
 206
 207         /*
 208          * Check if the module needs to boot from unipro.
 209          * For ES2: We need to check lowest 8 bits of 'value'.
 210          * For ES3: We need to check highest 8 bits out of 32 of 'value'.
 211          *
 212          * FIXME: Add code to find if we are on ES2 or ES3 to have separate
 213          * checks.
 214          */
 215         if (value == DME_TSI_UNIPRO_BOOT_STARTED ||
 216             value == DME_TSI_FALLBACK_UNIPRO_BOOT_STARTED)
 217                 intf->boot_over_unipro = true;
 218
 219         return gb_svc_dme_peer_set(hd->svc, intf->interface_id,
 220                                    DME_ATTR_T_TST_SRC_INCREMENT,
 221                                    DME_ATTR_SELECTOR_INDEX, 0);
 222 }
 223
 224 int gb_svc_connection_create(struct gb_svc *svc,
 225                                 u8 intf1_id, u16 cport1_id,
 226                                 u8 intf2_id, u16 cport2_id,
 227                                 bool boot_over_unipro)
 228 {
 229         struct gb_svc_conn_create_request request;
 230
 231         request.intf1_id = intf1_id;
 232         request.cport1_id = cpu_to_le16(cport1_id);
 233         request.intf2_id = intf2_id;
 234         request.cport2_id = cpu_to_le16(cport2_id);
 235         /*
 236          * XXX: fix connections paramaters to TC0 and all CPort flags
 237          * for now.
 238          */
 239         request.tc = 0;
 240
 241         /*
 242          * We need to skip setting E2EFC and other flags to the connection
 243          * create request, for all cports, on an interface that need to boot
 244          * over unipro, i.e. interfaces required to download firmware.
 245          */
 246         if (boot_over_unipro)
 247                 request.flags = CPORT_FLAGS_CSV_N | CPORT_FLAGS_CSD_N;
 248         else
 249                 request.flags = CPORT_FLAGS_CSV_N | CPORT_FLAGS_E2EFC;
 250
 251         return gb_operation_sync(svc->connection, GB_SVC_TYPE_CONN_CREATE,
 252                                  &request, sizeof(request), NULL, 0);
 253 }
 254 EXPORT_SYMBOL_GPL(gb_svc_connection_create);
 255
 256 void gb_svc_connection_destroy(struct gb_svc *svc, u8 intf1_id, u16 cport1_id,
 257                                u8 intf2_id, u16 cport2_id)
 258 {
 259         struct gb_svc_conn_destroy_request request;
 260         struct gb_connection *connection = svc->connection;
 261         int ret;
 262
 263         request.intf1_id = intf1_id;
 264         request.cport1_id = cpu_to_le16(cport1_id);
 265         request.intf2_id = intf2_id;
 266         request.cport2_id = cpu_to_le16(cport2_id);
 267
 268         ret = gb_operation_sync(connection, GB_SVC_TYPE_CONN_DESTROY,
 269                                 &request, sizeof(request), NULL, 0);
 270         if (ret)
 271                 pr_err("failed to destroy connection (%hhu:%hu %hhu:%hu) %d\n",
 272                        intf1_id, cport1_id, intf2_id, cport2_id, ret);
 273 }
 274 EXPORT_SYMBOL_GPL(gb_svc_connection_destroy);
 275
 276 /* Creates bi-directional routes between the devices */
 277 static int gb_svc_route_create(struct gb_svc *svc, u8 intf1_id, u8 dev1_id,
 278                                u8 intf2_id, u8 dev2_id)
 279 {
 280         struct gb_svc_route_create_request request;
 281
 282         request.intf1_id = intf1_id;
 283         request.dev1_id = dev1_id;
 284         request.intf2_id = intf2_id;
 285         request.dev2_id = dev2_id;
 286
 287         return gb_operation_sync(svc->connection, GB_SVC_TYPE_ROUTE_CREATE,
 288                                  &request, sizeof(request), NULL, 0);
 289 }
 290
 291 /* Destroys bi-directional routes between the devices */
 292 static void gb_svc_route_destroy(struct gb_svc *svc, u8 intf1_id, u8 intf2_id)
 293 {
 294         struct gb_svc_route_destroy_request request;
 295         int ret;
 296
 297         request.intf1_id = intf1_id;
 298         request.intf2_id = intf2_id;
 299
 300         ret = gb_operation_sync(svc->connection, GB_SVC_TYPE_ROUTE_DESTROY,
 301                                 &request, sizeof(request), NULL, 0);
 302         if (ret)
 303                 pr_err("failed to destroy route (%hhu %hhu) %d\n",
 304                         intf1_id, intf2_id, ret);
 305 }
 306
 307 static int gb_svc_version_request(struct gb_operation *op)
 308 {
 309         struct gb_connection *connection = op->connection;
 310         struct gb_protocol_version_request *request;
 311         struct gb_protocol_version_response *response;
 312
 313         if (op->request->payload_size < sizeof(*request)) {
 314                 pr_err("%d: short version request (%zu < %zu)\n",
 315                                 connection->intf_cport_id,
 316                                 op->request->payload_size,
 317                                 sizeof(*request));
 318                 return -EINVAL;
 319         }
 320
 321         request = op->request->payload;
 322
 323         if (request->major > GB_SVC_VERSION_MAJOR) {
 324                 pr_err("%d: unsupported major version (%hhu > %hhu)\n",
 325                        connection->intf_cport_id, request->major,
 326                        GB_SVC_VERSION_MAJOR);
 327                 return -ENOTSUPP;
 328         }
 329
 330         connection->module_major = request->major;
 331         connection->module_minor = request->minor;
 332
 333         if (!gb_operation_response_alloc(op, sizeof(*response), GFP_KERNEL)) {
 334                 pr_err("%d: error allocating response\n",
 335                        connection->intf_cport_id);
 336                 return -ENOMEM;
 337         }
 338
 339         response = op->response->payload;
 340         response->major = connection->module_major;
 341         response->minor = connection->module_minor;
 342
 343         return 0;
 344 }
 345
 346 static int gb_svc_hello(struct gb_operation *op)
 347 {
 348         struct gb_connection *connection = op->connection;
 349         struct gb_host_device *hd = connection->hd;
 350         struct gb_svc_hello_request *hello_request;
 351         struct gb_interface *intf;
 352         u16 endo_id;
 353         u8 interface_id;
 354         int ret;
 355
 356         /*
 357          * SVC sends information about the endo and interface-id on the hello
 358          * request, use that to create an endo.
 359          */
 360         if (op->request->payload_size < sizeof(*hello_request)) {
 361                 pr_err("%d: Illegal size of hello request (%zu < %zu)\n",
 362                        connection->intf_cport_id, op->request->payload_size,
 363                        sizeof(*hello_request));
 364                 return -EINVAL;
 365         }
 366
 367         hello_request = op->request->payload;
 368         endo_id = le16_to_cpu(hello_request->endo_id);
 369         interface_id = hello_request->interface_id;
 370
 371         /* Setup Endo */
 372         ret = greybus_endo_setup(hd, endo_id, interface_id);
 373         if (ret)
 374                 return ret;
 375
 376         /*
 377          * Endo and its modules are ready now, fix AP's partially initialized
 378          * svc protocol and its connection.
 379          */
 380         intf = gb_ap_interface_create(hd, connection, interface_id);
 381         if (!intf) {
 382                 gb_endo_remove(hd->endo);
 383                 return ret;
 384         }
 385
 386         return 0;
 387 }
 388
 389 static void svc_intf_remove(struct gb_connection *connection,
 390                             struct gb_interface *intf)
 391 {
 392         struct gb_host_device *hd = connection->hd;
 393         struct gb_svc *svc = connection->private;
 394         u8 intf_id = intf->interface_id;
 395         u8 device_id;
 396
 397         device_id = intf->device_id;
 398         gb_interface_remove(intf);
 399
 400         /*
 401          * Destroy the two-way route between the AP and the interface.
 402          */
 403         gb_svc_route_destroy(svc, hd->endo->ap_intf_id, intf_id);
 404
 405         ida_simple_remove(&svc->device_id_map, device_id);
 406 }
 407
 408 /*
 409  * 'struct svc_hotplug' should be freed by svc_process_hotplug() before it
 410  * returns, irrespective of success or Failure in bringing up the module.
 411  */
 412 static void svc_process_hotplug(struct work_struct *work)
 413 {
 414         struct svc_hotplug *svc_hotplug = container_of(work, struct svc_hotplug,
 415                                                        work);
 416         struct gb_svc_intf_hotplug_request *hotplug = &svc_hotplug->data;
 417         struct gb_connection *connection = svc_hotplug->connection;
 418         struct gb_svc *svc = connection->private;
 419         struct gb_host_device *hd = connection->hd;
 420         struct gb_interface *intf;
 421         u8 intf_id, device_id;
 422         int ret;
 423
 424         /*
 425          * Grab the information we need.
 426          */
 427         intf_id = hotplug->intf_id;
 428
 429         intf = gb_interface_find(hd, intf_id);
 430         if (intf) {
 431                 /*
 432                  * We have received a hotplug request for an interface that
 433                  * already exists.
 434                  *
 435                  * This can happen in cases like:
 436                  * - bootrom loading the firmware image and booting into that,
 437                  *   which only generates a hotplug event. i.e. no hot-unplug
 438                  *   event.
 439                  * - Or the firmware on the module crashed and sent hotplug
 440                  *   request again to the SVC, which got propagated to AP.
 441                  *
 442                  * Remove the interface and add it again, and let user know
 443                  * about this with a print message.
 444                  */
 445                 pr_info("%d: Removed interface (%hhu) to add it again\n",
 446                         connection->intf_cport_id, intf_id);
 447                 svc_intf_remove(connection, intf);
 448         }
 449
 450         intf = gb_interface_create(hd, intf_id);
 451         if (!intf) {
 452                 pr_err("%d: Failed to create interface with id %hhu\n",
 453                        connection->intf_cport_id, intf_id);
 454                 goto free_svc_hotplug;
 455         }
 456
 457         ret = gb_svc_read_and_clear_module_boot_status(intf);
 458         if (ret)
 459                 goto destroy_interface;
 460
 461         intf->unipro_mfg_id = le32_to_cpu(hotplug->data.unipro_mfg_id);
 462         intf->unipro_prod_id = le32_to_cpu(hotplug->data.unipro_prod_id);
 463         intf->vendor_id = le32_to_cpu(hotplug->data.ara_vend_id);
 464         intf->product_id = le32_to_cpu(hotplug->data.ara_prod_id);
 465
 466         /*
 467          * Create a device id for the interface:
 468          * - device id 0 (GB_DEVICE_ID_SVC) belongs to the SVC
 469          * - device id 1 (GB_DEVICE_ID_AP) belongs to the AP
 470          *
 471          * XXX Do we need to allocate device ID for SVC or the AP here? And what
 472          * XXX about an AP with multiple interface blocks?
 473          */
 474         device_id = ida_simple_get(&svc->device_id_map,
 475                                    GB_DEVICE_ID_MODULES_START, 0, GFP_KERNEL);
 476         if (device_id < 0) {
 477                 ret = device_id;
 478                 pr_err("%d: Failed to allocate device id for interface with id %hhu (%d)\n",
 479                        connection->intf_cport_id, intf_id, ret);
 480                 goto destroy_interface;
 481         }
 482
 483         ret = gb_svc_intf_device_id(svc, intf_id, device_id);
 484         if (ret) {
 485                 pr_err("%d: Device id operation failed, interface %hhu device_id %hhu (%d)\n",
 486                        connection->intf_cport_id, intf_id, device_id, ret);
 487                 goto ida_put;
 488         }
 489
 490         /*
 491          * Create a two-way route between the AP and the new interface
 492          */
 493         ret = gb_svc_route_create(svc, hd->endo->ap_intf_id, GB_DEVICE_ID_AP,
 494                                   intf_id, device_id);
 495         if (ret) {
 496                 pr_err("%d: Route create operation failed, interface %hhu device_id %hhu (%d)\n",
 497                        connection->intf_cport_id, intf_id, device_id, ret);
 498                 goto svc_id_free;
 499         }
 500
 501         ret = gb_interface_init(intf, device_id);
 502         if (ret) {
 503                 pr_err("%d: Failed to initialize interface, interface %hhu device_id %hhu (%d)\n",
 504                        connection->intf_cport_id, intf_id, device_id, ret);
 505                 goto destroy_route;
 506         }
 507
 508         goto free_svc_hotplug;
 509
 510 destroy_route:
 511         gb_svc_route_destroy(svc, hd->endo->ap_intf_id, intf_id);
 512 svc_id_free:
 513         /*
 514          * XXX Should we tell SVC that this id doesn't belong to interface
 515          * XXX anymore.
 516          */
 517 ida_put:
 518         ida_simple_remove(&svc->device_id_map, device_id);
 519 destroy_interface:
 520         gb_interface_remove(intf);
 521 free_svc_hotplug:
 522         kfree(svc_hotplug);
 523 }
 524
 525 /*
 526  * Bringing up a module can be time consuming, as that may require lots of
 527  * initialization on the module side. Over that, we may also need to download
 528  * the firmware first and flash that on the module.
 529  *
 530  * In order to make other hotplug events to not wait for all this to finish,
 531  * handle most of module hotplug stuff outside of the hotplug callback, with
 532  * help of a workqueue.
 533  */
 534 static int gb_svc_intf_hotplug_recv(struct gb_operation *op)
 535 {
 536         struct gb_message *request = op->request;
 537         struct svc_hotplug *svc_hotplug;
 538
 539         if (request->payload_size < sizeof(svc_hotplug->data)) {
 540                 pr_err("%d: short hotplug request received (%zu < %zu)\n",
 541                        op->connection->intf_cport_id, request->payload_size,
 542                        sizeof(svc_hotplug->data));
 543                 return -EINVAL;
 544         }
 545
 546         svc_hotplug = kmalloc(sizeof(*svc_hotplug), GFP_KERNEL);
 547         if (!svc_hotplug)
 548                 return -ENOMEM;
 549
 550         svc_hotplug->connection = op->connection;
 551         memcpy(&svc_hotplug->data, op->request->payload, sizeof(svc_hotplug->data));
 552
 553         INIT_WORK(&svc_hotplug->work, svc_process_hotplug);
 554         queue_work(system_unbound_wq, &svc_hotplug->work);
 555
 556         return 0;
 557 }
 558
 559 static int gb_svc_intf_hot_unplug_recv(struct gb_operation *op)
 560 {
 561         struct gb_message *request = op->request;
 562         struct gb_svc_intf_hot_unplug_request *hot_unplug = request->payload;
 563         struct gb_host_device *hd = op->connection->hd;
 564         struct gb_interface *intf;
 565         u8 intf_id;
 566
 567         if (request->payload_size < sizeof(*hot_unplug)) {
 568                 pr_err("connection %d: short hot unplug request received (%zu < %zu)\n",
 569                        op->connection->intf_cport_id, request->payload_size,
 570                        sizeof(*hot_unplug));
 571                 return -EINVAL;
 572         }
 573
 574         intf_id = hot_unplug->intf_id;
 575
 576         intf = gb_interface_find(hd, intf_id);
 577         if (!intf) {
 578                 pr_err("connection %d: Couldn't find interface for id %hhu\n",
 579                        op->connection->intf_cport_id, intf_id);
 580                 return -EINVAL;
 581         }
 582
 583         svc_intf_remove(op->connection, intf);
 584
 585         return 0;
 586 }
 587
 588 static int gb_svc_intf_reset_recv(struct gb_operation *op)
 589 {
 590         struct gb_message *request = op->request;
 591         struct gb_svc_intf_reset_request *reset;
 592         u8 intf_id;
 593
 594         if (request->payload_size < sizeof(*reset)) {
 595                 pr_err("connection %d: short reset request received (%zu < %zu)\n",
 596                        op->connection->intf_cport_id, request->payload_size,
 597                        sizeof(*reset));
 598                 return -EINVAL;
 599         }
 600         reset = request->payload;
 601
 602         intf_id = reset->intf_id;
 603
 604         /* FIXME Reset the interface here */
 605
 606         return 0;
 607 }
 608
 609 static int gb_svc_request_recv(u8 type, struct gb_operation *op)
 610 {
 611         struct gb_connection *connection = op->connection;
 612         struct gb_svc *svc = connection->private;
 613         int ret = 0;
 614
 615         /*
 616          * SVC requests need to follow a specific order (at least initially) and
 617          * below code takes care of enforcing that. The expected order is:
 618          * - PROTOCOL_VERSION
 619          * - SVC_HELLO
 620          * - Any other request, but the earlier two.
 621          *
 622          * Incoming requests are guaranteed to be serialized and so we don't
 623          * need to protect 'state' for any races.
 624          */
 625         switch (type) {
 626         case GB_REQUEST_TYPE_PROTOCOL_VERSION:
 627                 if (svc->state != GB_SVC_STATE_RESET)
 628                         ret = -EINVAL;
 629                 break;
 630         case GB_SVC_TYPE_SVC_HELLO:
 631                 if (svc->state != GB_SVC_STATE_PROTOCOL_VERSION)
 632                         ret = -EINVAL;
 633                 break;
 634         default:
 635                 if (svc->state != GB_SVC_STATE_SVC_HELLO)
 636                         ret = -EINVAL;
 637                 break;
 638         }
 639
 640         if (ret) {
 641                 pr_warn("connection %d: unexpected SVC request 0x%02x received (state %u)\n",
 642                         connection->intf_cport_id, type, svc->state);
 643                 return ret;
 644         }
 645
 646         switch (type) {
 647         case GB_REQUEST_TYPE_PROTOCOL_VERSION:
 648                 ret = gb_svc_version_request(op);
 649                 if (!ret)
 650                         svc->state = GB_SVC_STATE_PROTOCOL_VERSION;
 651                 return ret;
 652         case GB_SVC_TYPE_SVC_HELLO:
 653                 ret = gb_svc_hello(op);
 654                 if (!ret)
 655                         svc->state = GB_SVC_STATE_SVC_HELLO;
 656                 return ret;
 657         case GB_SVC_TYPE_INTF_HOTPLUG:
 658                 return gb_svc_intf_hotplug_recv(op);
 659         case GB_SVC_TYPE_INTF_HOT_UNPLUG:
 660                 return gb_svc_intf_hot_unplug_recv(op);
 661         case GB_SVC_TYPE_INTF_RESET:
 662                 return gb_svc_intf_reset_recv(op);
 663         default:
 664                 pr_err("connection %d: unsupported request: %hhu\n",
 665                        connection->intf_cport_id, type);
 666                 return -EINVAL;
 667         }
 668 }
 669
 670 static int gb_svc_connection_init(struct gb_connection *connection)
 671 {
 672         struct gb_svc *svc;
 673
 674         svc = kzalloc(sizeof(*svc), GFP_KERNEL);
 675         if (!svc)
 676                 return -ENOMEM;
 677
 678         connection->hd->svc = svc;
 679         svc->state = GB_SVC_STATE_RESET;
 680         svc->connection = connection;
 681         connection->private = svc;
 682
 683         WARN_ON(connection->hd->initial_svc_connection);
 684         connection->hd->initial_svc_connection = connection;
 685
 686         ida_init(&svc->device_id_map);
 687
 688         return 0;
 689 }
 690
 691 static void gb_svc_connection_exit(struct gb_connection *connection)
 692 {
 693         struct gb_svc *svc = connection->private;
 694
 695         ida_destroy(&svc->device_id_map);
 696         connection->hd->svc = NULL;
 697         connection->private = NULL;
 698         kfree(svc);
 699 }
 700
 701 static struct gb_protocol svc_protocol = {
 702         .name                   = "svc",
 703         .id                     = GREYBUS_PROTOCOL_SVC,
 704         .major                  = GB_SVC_VERSION_MAJOR,
 705         .minor                  = GB_SVC_VERSION_MINOR,
 706         .connection_init        = gb_svc_connection_init,
 707         .connection_exit        = gb_svc_connection_exit,
 708         .request_recv           = gb_svc_request_recv,
 709         .flags                  = GB_PROTOCOL_SKIP_CONTROL_CONNECTED |
 710                                   GB_PROTOCOL_SKIP_CONTROL_DISCONNECTED |
 711                                   GB_PROTOCOL_NO_BUNDLE |
 712                                   GB_PROTOCOL_SKIP_VERSION |
 713                                   GB_PROTOCOL_SKIP_SVC_CONNECTION,
 714 };
 715 gb_builtin_protocol_driver(svc_protocol);