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 #include <linux/input.h>
  11 #include <linux/workqueue.h>
  12
  13 #include "greybus.h"
  14
  15 #define SVC_KEY_ARA_BUTTON      KEY_A
  16
  17 #define SVC_INTF_EJECT_TIMEOUT  9000
  18
  19 struct gb_svc_deferred_request {
  20         struct work_struct work;
  21         struct gb_operation *operation;
  22 };
  23
  24
  25 static ssize_t endo_id_show(struct device *dev,
  26                         struct device_attribute *attr, char *buf)
  27 {
  28         struct gb_svc *svc = to_gb_svc(dev);
  29
  30         return sprintf(buf, "0x%04x\n", svc->endo_id);
  31 }
  32 static DEVICE_ATTR_RO(endo_id);
  33
  34 static ssize_t ap_intf_id_show(struct device *dev,
  35                         struct device_attribute *attr, char *buf)
  36 {
  37         struct gb_svc *svc = to_gb_svc(dev);
  38
  39         return sprintf(buf, "%u\n", svc->ap_intf_id);
  40 }
  41 static DEVICE_ATTR_RO(ap_intf_id);
  42
  43
  44 // FIXME
  45 // This is a hack, we need to do this "right" and clean the interface up
  46 // properly, not just forcibly yank the thing out of the system and hope for the
  47 // best.  But for now, people want their modules to come out without having to
  48 // throw the thing to the ground or get out a screwdriver.
  49 static ssize_t intf_eject_store(struct device *dev,
  50                                 struct device_attribute *attr, const char *buf,
  51                                 size_t len)
  52 {
  53         struct gb_svc *svc = to_gb_svc(dev);
  54         unsigned short intf_id;
  55         int ret;
  56
  57         ret = kstrtou16(buf, 10, &intf_id);
  58         if (ret < 0)
  59                 return ret;
  60
  61         dev_warn(dev, "Forcibly trying to eject interface %d\n", intf_id);
  62
  63         ret = gb_svc_intf_eject(svc, intf_id);
  64         if (ret < 0)
  65                 return ret;
  66
  67         return len;
  68 }
  69 static DEVICE_ATTR_WO(intf_eject);
  70
  71 static ssize_t watchdog_show(struct device *dev, struct device_attribute *attr,
  72                              char *buf)
  73 {
  74         struct gb_svc *svc = to_gb_svc(dev);
  75
  76         return sprintf(buf, "%s\n",
  77                        gb_svc_watchdog_enabled(svc) ? "enabled" : "disabled");
  78 }
  79
  80 static ssize_t watchdog_store(struct device *dev,
  81                               struct device_attribute *attr, const char *buf,
  82                               size_t len)
  83 {
  84         struct gb_svc *svc = to_gb_svc(dev);
  85         int retval;
  86         bool user_request;
  87
  88         retval = strtobool(buf, &user_request);
  89         if (retval)
  90                 return retval;
  91
  92         if (user_request)
  93                 retval = gb_svc_watchdog_enable(svc);
  94         else
  95                 retval = gb_svc_watchdog_disable(svc);
  96         if (retval)
  97                 return retval;
  98         return len;
  99 }
 100 static DEVICE_ATTR_RW(watchdog);
 101
 102 static struct attribute *svc_attrs[] = {
 103         &dev_attr_endo_id.attr,
 104         &dev_attr_ap_intf_id.attr,
 105         &dev_attr_intf_eject.attr,
 106         &dev_attr_watchdog.attr,
 107         NULL,
 108 };
 109 ATTRIBUTE_GROUPS(svc);
 110
 111 static int gb_svc_intf_device_id(struct gb_svc *svc, u8 intf_id, u8 device_id)
 112 {
 113         struct gb_svc_intf_device_id_request request;
 114
 115         request.intf_id = intf_id;
 116         request.device_id = device_id;
 117
 118         return gb_operation_sync(svc->connection, GB_SVC_TYPE_INTF_DEVICE_ID,
 119                                  &request, sizeof(request), NULL, 0);
 120 }
 121
 122 int gb_svc_intf_eject(struct gb_svc *svc, u8 intf_id)
 123 {
 124         struct gb_svc_intf_eject_request request;
 125         int ret;
 126
 127         request.intf_id = intf_id;
 128
 129         /*
 130          * The pulse width for module release in svc is long so we need to
 131          * increase the timeout so the operation will not return to soon.
 132          */
 133         ret = gb_operation_sync_timeout(svc->connection,
 134                                         GB_SVC_TYPE_INTF_EJECT, &request,
 135                                         sizeof(request), NULL, 0,
 136                                         SVC_INTF_EJECT_TIMEOUT);
 137         if (ret) {
 138                 dev_err(&svc->dev, "failed to eject interface %u\n", intf_id);
 139                 return ret;
 140         }
 141
 142         return 0;
 143 }
 144
 145 int gb_svc_dme_peer_get(struct gb_svc *svc, u8 intf_id, u16 attr, u16 selector,
 146                         u32 *value)
 147 {
 148         struct gb_svc_dme_peer_get_request request;
 149         struct gb_svc_dme_peer_get_response response;
 150         u16 result;
 151         int ret;
 152
 153         request.intf_id = intf_id;
 154         request.attr = cpu_to_le16(attr);
 155         request.selector = cpu_to_le16(selector);
 156
 157         ret = gb_operation_sync(svc->connection, GB_SVC_TYPE_DME_PEER_GET,
 158                                 &request, sizeof(request),
 159                                 &response, sizeof(response));
 160         if (ret) {
 161                 dev_err(&svc->dev, "failed to get DME attribute (%u 0x%04x %u): %d\n",
 162                                 intf_id, attr, selector, ret);
 163                 return ret;
 164         }
 165
 166         result = le16_to_cpu(response.result_code);
 167         if (result) {
 168                 dev_err(&svc->dev, "UniPro error while getting DME attribute (%u 0x%04x %u): %u\n",
 169                                 intf_id, attr, selector, result);
 170                 return -EIO;
 171         }
 172
 173         if (value)
 174                 *value = le32_to_cpu(response.attr_value);
 175
 176         return 0;
 177 }
 178 EXPORT_SYMBOL_GPL(gb_svc_dme_peer_get);
 179
 180 int gb_svc_dme_peer_set(struct gb_svc *svc, u8 intf_id, u16 attr, u16 selector,
 181                         u32 value)
 182 {
 183         struct gb_svc_dme_peer_set_request request;
 184         struct gb_svc_dme_peer_set_response response;
 185         u16 result;
 186         int ret;
 187
 188         request.intf_id = intf_id;
 189         request.attr = cpu_to_le16(attr);
 190         request.selector = cpu_to_le16(selector);
 191         request.value = cpu_to_le32(value);
 192
 193         ret = gb_operation_sync(svc->connection, GB_SVC_TYPE_DME_PEER_SET,
 194                                 &request, sizeof(request),
 195                                 &response, sizeof(response));
 196         if (ret) {
 197                 dev_err(&svc->dev, "failed to set DME attribute (%u 0x%04x %u %u): %d\n",
 198                                 intf_id, attr, selector, value, ret);
 199                 return ret;
 200         }
 201
 202         result = le16_to_cpu(response.result_code);
 203         if (result) {
 204                 dev_err(&svc->dev, "UniPro error while setting DME attribute (%u 0x%04x %u %u): %u\n",
 205                                 intf_id, attr, selector, value, result);
 206                 return -EIO;
 207         }
 208
 209         return 0;
 210 }
 211 EXPORT_SYMBOL_GPL(gb_svc_dme_peer_set);
 212
 213 /*
 214  * T_TstSrcIncrement is written by the module on ES2 as a stand-in for boot
 215  * status attribute ES3_INIT_STATUS. AP needs to read and clear it, after
 216  * reading a non-zero value from it.
 217  *
 218  * FIXME: This is module-hardware dependent and needs to be extended for every
 219  * type of module we want to support.
 220  */
 221 static int gb_svc_read_and_clear_module_boot_status(struct gb_interface *intf)
 222 {
 223         struct gb_host_device *hd = intf->hd;
 224         int ret;
 225         u32 value;
 226         u16 attr;
 227         u8 init_status;
 228
 229         /*
 230          * Check if the module is ES2 or ES3, and choose attr number
 231          * appropriately.
 232          * FIXME: Remove ES2 support from the kernel entirely.
 233          */
 234         if (intf->ddbl1_manufacturer_id == ES2_DDBL1_MFR_ID &&
 235                                 intf->ddbl1_product_id == ES2_DDBL1_PROD_ID)
 236                 attr = DME_ATTR_T_TST_SRC_INCREMENT;
 237         else
 238                 attr = DME_ATTR_ES3_INIT_STATUS;
 239
 240         /* Read and clear boot status in ES3_INIT_STATUS */
 241         ret = gb_svc_dme_peer_get(hd->svc, intf->interface_id, attr,
 242                                   DME_ATTR_SELECTOR_INDEX, &value);
 243
 244         if (ret)
 245                 return ret;
 246
 247         /*
 248          * A nonzero boot status indicates the module has finished
 249          * booting. Clear it.
 250          */
 251         if (!value) {
 252                 dev_err(&intf->dev, "Module not ready yet\n");
 253                 return -ENODEV;
 254         }
 255
 256         /*
 257          * Check if the module needs to boot from UniPro.
 258          * For ES2: We need to check lowest 8 bits of 'value'.
 259          * For ES3: We need to check highest 8 bits out of 32 of 'value'.
 260          * FIXME: Remove ES2 support from the kernel entirely.
 261          */
 262         if (intf->ddbl1_manufacturer_id == ES2_DDBL1_MFR_ID &&
 263                                 intf->ddbl1_product_id == ES2_DDBL1_PROD_ID)
 264                 init_status = value;
 265         else
 266                 init_status = value >> 24;
 267
 268         if (init_status == DME_DIS_UNIPRO_BOOT_STARTED ||
 269                                 init_status == DME_DIS_FALLBACK_UNIPRO_BOOT_STARTED)
 270                 intf->boot_over_unipro = true;
 271
 272         return gb_svc_dme_peer_set(hd->svc, intf->interface_id, attr,
 273                                    DME_ATTR_SELECTOR_INDEX, 0);
 274 }
 275
 276 int gb_svc_connection_create(struct gb_svc *svc,
 277                                 u8 intf1_id, u16 cport1_id,
 278                                 u8 intf2_id, u16 cport2_id,
 279                                 u8 cport_flags)
 280 {
 281         struct gb_svc_conn_create_request request;
 282
 283         request.intf1_id = intf1_id;
 284         request.cport1_id = cpu_to_le16(cport1_id);
 285         request.intf2_id = intf2_id;
 286         request.cport2_id = cpu_to_le16(cport2_id);
 287         request.tc = 0;         /* TC0 */
 288         request.flags = cport_flags;
 289
 290         return gb_operation_sync(svc->connection, GB_SVC_TYPE_CONN_CREATE,
 291                                  &request, sizeof(request), NULL, 0);
 292 }
 293 EXPORT_SYMBOL_GPL(gb_svc_connection_create);
 294
 295 void gb_svc_connection_destroy(struct gb_svc *svc, u8 intf1_id, u16 cport1_id,
 296                                u8 intf2_id, u16 cport2_id)
 297 {
 298         struct gb_svc_conn_destroy_request request;
 299         struct gb_connection *connection = svc->connection;
 300         int ret;
 301
 302         request.intf1_id = intf1_id;
 303         request.cport1_id = cpu_to_le16(cport1_id);
 304         request.intf2_id = intf2_id;
 305         request.cport2_id = cpu_to_le16(cport2_id);
 306
 307         ret = gb_operation_sync(connection, GB_SVC_TYPE_CONN_DESTROY,
 308                                 &request, sizeof(request), NULL, 0);
 309         if (ret) {
 310                 dev_err(&svc->dev, "failed to destroy connection (%u:%u %u:%u): %d\n",
 311                                 intf1_id, cport1_id, intf2_id, cport2_id, ret);
 312         }
 313 }
 314 EXPORT_SYMBOL_GPL(gb_svc_connection_destroy);
 315
 316 /* Creates bi-directional routes between the devices */
 317 static int gb_svc_route_create(struct gb_svc *svc, u8 intf1_id, u8 dev1_id,
 318                                u8 intf2_id, u8 dev2_id)
 319 {
 320         struct gb_svc_route_create_request request;
 321
 322         request.intf1_id = intf1_id;
 323         request.dev1_id = dev1_id;
 324         request.intf2_id = intf2_id;
 325         request.dev2_id = dev2_id;
 326
 327         return gb_operation_sync(svc->connection, GB_SVC_TYPE_ROUTE_CREATE,
 328                                  &request, sizeof(request), NULL, 0);
 329 }
 330
 331 /* Destroys bi-directional routes between the devices */
 332 static void gb_svc_route_destroy(struct gb_svc *svc, u8 intf1_id, u8 intf2_id)
 333 {
 334         struct gb_svc_route_destroy_request request;
 335         int ret;
 336
 337         request.intf1_id = intf1_id;
 338         request.intf2_id = intf2_id;
 339
 340         ret = gb_operation_sync(svc->connection, GB_SVC_TYPE_ROUTE_DESTROY,
 341                                 &request, sizeof(request), NULL, 0);
 342         if (ret) {
 343                 dev_err(&svc->dev, "failed to destroy route (%u %u): %d\n",
 344                                 intf1_id, intf2_id, ret);
 345         }
 346 }
 347
 348 int gb_svc_intf_set_power_mode(struct gb_svc *svc, u8 intf_id, u8 hs_series,
 349                                u8 tx_mode, u8 tx_gear, u8 tx_nlanes,
 350                                u8 rx_mode, u8 rx_gear, u8 rx_nlanes,
 351                                u8 flags, u32 quirks)
 352 {
 353         struct gb_svc_intf_set_pwrm_request request;
 354         struct gb_svc_intf_set_pwrm_response response;
 355         int ret;
 356
 357         request.intf_id = intf_id;
 358         request.hs_series = hs_series;
 359         request.tx_mode = tx_mode;
 360         request.tx_gear = tx_gear;
 361         request.tx_nlanes = tx_nlanes;
 362         request.rx_mode = rx_mode;
 363         request.rx_gear = rx_gear;
 364         request.rx_nlanes = rx_nlanes;
 365         request.flags = flags;
 366         request.quirks = cpu_to_le32(quirks);
 367
 368         ret = gb_operation_sync(svc->connection, GB_SVC_TYPE_INTF_SET_PWRM,
 369                                 &request, sizeof(request),
 370                                 &response, sizeof(response));
 371         if (ret < 0)
 372                 return ret;
 373
 374         return le16_to_cpu(response.result_code);
 375 }
 376 EXPORT_SYMBOL_GPL(gb_svc_intf_set_power_mode);
 377
 378 int gb_svc_ping(struct gb_svc *svc)
 379 {
 380         return gb_operation_sync_timeout(svc->connection, GB_SVC_TYPE_PING,
 381                                          NULL, 0, NULL, 0,
 382                                          GB_OPERATION_TIMEOUT_DEFAULT * 2);
 383 }
 384 EXPORT_SYMBOL_GPL(gb_svc_ping);
 385
 386 static int gb_svc_version_request(struct gb_operation *op)
 387 {
 388         struct gb_connection *connection = op->connection;
 389         struct gb_svc *svc = gb_connection_get_data(connection);
 390         struct gb_protocol_version_request *request;
 391         struct gb_protocol_version_response *response;
 392
 393         if (op->request->payload_size < sizeof(*request)) {
 394                 dev_err(&svc->dev, "short version request (%zu < %zu)\n",
 395                                 op->request->payload_size,
 396                                 sizeof(*request));
 397                 return -EINVAL;
 398         }
 399
 400         request = op->request->payload;
 401
 402         if (request->major > GB_SVC_VERSION_MAJOR) {
 403                 dev_warn(&svc->dev, "unsupported major version (%u > %u)\n",
 404                                 request->major, GB_SVC_VERSION_MAJOR);
 405                 return -ENOTSUPP;
 406         }
 407
 408         svc->protocol_major = request->major;
 409         svc->protocol_minor = request->minor;
 410
 411         if (!gb_operation_response_alloc(op, sizeof(*response), GFP_KERNEL))
 412                 return -ENOMEM;
 413
 414         response = op->response->payload;
 415         response->major = svc->protocol_major;
 416         response->minor = svc->protocol_minor;
 417
 418         return 0;
 419 }
 420
 421 static int gb_svc_hello(struct gb_operation *op)
 422 {
 423         struct gb_connection *connection = op->connection;
 424         struct gb_svc *svc = gb_connection_get_data(connection);
 425         struct gb_svc_hello_request *hello_request;
 426         int ret;
 427
 428         if (op->request->payload_size < sizeof(*hello_request)) {
 429                 dev_warn(&svc->dev, "short hello request (%zu < %zu)\n",
 430                                 op->request->payload_size,
 431                                 sizeof(*hello_request));
 432                 return -EINVAL;
 433         }
 434
 435         hello_request = op->request->payload;
 436         svc->endo_id = le16_to_cpu(hello_request->endo_id);
 437         svc->ap_intf_id = hello_request->interface_id;
 438
 439         ret = device_add(&svc->dev);
 440         if (ret) {
 441                 dev_err(&svc->dev, "failed to register svc device: %d\n", ret);
 442                 return ret;
 443         }
 444
 445         ret = input_register_device(svc->input);
 446         if (ret) {
 447                 dev_err(&svc->dev, "failed to register input: %d\n", ret);
 448                 device_del(&svc->dev);
 449                 return ret;
 450         }
 451
 452         ret = gb_svc_watchdog_create(svc);
 453         if (ret) {
 454                 dev_err(&svc->dev, "failed to create watchdog: %d\n", ret);
 455                 input_unregister_device(svc->input);
 456                 device_del(&svc->dev);
 457                 return ret;
 458         }
 459
 460         return 0;
 461 }
 462
 463 static int gb_svc_interface_route_create(struct gb_svc *svc,
 464                                                 struct gb_interface *intf)
 465 {
 466         u8 intf_id = intf->interface_id;
 467         u8 device_id;
 468         int ret;
 469
 470         /*
 471          * Create a device id for the interface:
 472          * - device id 0 (GB_DEVICE_ID_SVC) belongs to the SVC
 473          * - device id 1 (GB_DEVICE_ID_AP) belongs to the AP
 474          *
 475          * XXX Do we need to allocate device ID for SVC or the AP here? And what
 476          * XXX about an AP with multiple interface blocks?
 477          */
 478         ret = ida_simple_get(&svc->device_id_map,
 479                              GB_DEVICE_ID_MODULES_START, 0, GFP_KERNEL);
 480         if (ret < 0) {
 481                 dev_err(&svc->dev, "failed to allocate device id for interface %u: %d\n",
 482                                 intf_id, ret);
 483                 return ret;
 484         }
 485         device_id = ret;
 486
 487         ret = gb_svc_intf_device_id(svc, intf_id, device_id);
 488         if (ret) {
 489                 dev_err(&svc->dev, "failed to set device id %u for interface %u: %d\n",
 490                                 device_id, intf_id, ret);
 491                 goto err_ida_remove;
 492         }
 493
 494         /* Create a two-way route between the AP and the new interface. */
 495         ret = gb_svc_route_create(svc, svc->ap_intf_id, GB_DEVICE_ID_AP,
 496                                   intf_id, device_id);
 497         if (ret) {
 498                 dev_err(&svc->dev, "failed to create route to interface %u (device id %u): %d\n",
 499                                 intf_id, device_id, ret);
 500                 goto err_svc_id_free;
 501         }
 502
 503         intf->device_id = device_id;
 504
 505         return 0;
 506
 507 err_svc_id_free:
 508         /*
 509          * XXX Should we tell SVC that this id doesn't belong to interface
 510          * XXX anymore.
 511          */
 512 err_ida_remove:
 513         ida_simple_remove(&svc->device_id_map, device_id);
 514
 515         return ret;
 516 }
 517
 518 static void gb_svc_interface_route_destroy(struct gb_svc *svc,
 519                                                 struct gb_interface *intf)
 520 {
 521         if (intf->device_id == GB_DEVICE_ID_BAD)
 522                 return;
 523
 524         gb_svc_route_destroy(svc, svc->ap_intf_id, intf->interface_id);
 525         ida_simple_remove(&svc->device_id_map, intf->device_id);
 526         intf->device_id = GB_DEVICE_ID_BAD;
 527 }
 528
 529 static void gb_svc_intf_remove(struct gb_svc *svc, struct gb_interface *intf)
 530 {
 531         intf->disconnected = true;
 532
 533         gb_interface_disable(intf);
 534         gb_svc_interface_route_destroy(svc, intf);
 535         gb_interface_remove(intf);
 536 }
 537
 538 static void gb_svc_process_intf_hotplug(struct gb_operation *operation)
 539 {
 540         struct gb_svc_intf_hotplug_request *request;
 541         struct gb_connection *connection = operation->connection;
 542         struct gb_svc *svc = gb_connection_get_data(connection);
 543         struct gb_host_device *hd = connection->hd;
 544         struct gb_interface *intf;
 545         u8 intf_id;
 546         u32 vendor_id = 0;
 547         u32 product_id = 0;
 548         int ret;
 549
 550         /* The request message size has already been verified. */
 551         request = operation->request->payload;
 552         intf_id = request->intf_id;
 553
 554         dev_dbg(&svc->dev, "%s - id = %u\n", __func__, intf_id);
 555
 556         intf = gb_interface_find(hd, intf_id);
 557         if (intf) {
 558                 /*
 559                  * For ES2, we need to maintain the same vendor/product ids we
 560                  * got from bootrom, otherwise userspace can't distinguish
 561                  * between modules.
 562                  */
 563                 vendor_id = intf->vendor_id;
 564                 product_id = intf->product_id;
 565
 566                 /*
 567                  * We have received a hotplug request for an interface that
 568                  * already exists.
 569                  *
 570                  * This can happen in cases like:
 571                  * - bootrom loading the firmware image and booting into that,
 572                  *   which only generates a hotplug event. i.e. no hot-unplug
 573                  *   event.
 574                  * - Or the firmware on the module crashed and sent hotplug
 575                  *   request again to the SVC, which got propagated to AP.
 576                  *
 577                  * Remove the interface and add it again, and let user know
 578                  * about this with a print message.
 579                  */
 580                 dev_info(&svc->dev, "removing interface %u to add it again\n",
 581                                 intf_id);
 582                 gb_svc_intf_remove(svc, intf);
 583         }
 584
 585         intf = gb_interface_create(hd, intf_id);
 586         if (!intf) {
 587                 dev_err(&svc->dev, "failed to create interface %u\n",
 588                                 intf_id);
 589                 return;
 590         }
 591
 592         intf->ddbl1_manufacturer_id = le32_to_cpu(request->data.ddbl1_mfr_id);
 593         intf->ddbl1_product_id = le32_to_cpu(request->data.ddbl1_prod_id);
 594         intf->vendor_id = le32_to_cpu(request->data.ara_vend_id);
 595         intf->product_id = le32_to_cpu(request->data.ara_prod_id);
 596         intf->serial_number = le64_to_cpu(request->data.serial_number);
 597
 598         /*
 599          * Use VID/PID specified at hotplug if:
 600          * - Bridge ASIC chip isn't ES2
 601          * - Received non-zero Vendor/Product ids
 602          *
 603          * Otherwise, use the ids we received from bootrom.
 604          */
 605         if (intf->ddbl1_manufacturer_id == ES2_DDBL1_MFR_ID &&
 606             intf->ddbl1_product_id == ES2_DDBL1_PROD_ID &&
 607             intf->vendor_id == 0 && intf->product_id == 0) {
 608                 intf->vendor_id = vendor_id;
 609                 intf->product_id = product_id;
 610         }
 611
 612         ret = gb_svc_read_and_clear_module_boot_status(intf);
 613         if (ret) {
 614                 dev_err(&svc->dev, "failed to clear boot status of interface %u: %d\n",
 615                                 intf_id, ret);
 616                 goto out_interface_add;
 617         }
 618
 619         ret = gb_svc_interface_route_create(svc, intf);
 620         if (ret)
 621                 goto out_interface_add;
 622
 623         ret = gb_interface_enable(intf);
 624         if (ret) {
 625                 dev_err(&svc->dev, "failed to enable interface %u: %d\n",
 626                                 intf_id, ret);
 627                 goto out_interface_add;
 628         }
 629
 630 out_interface_add:
 631         gb_interface_add(intf);
 632 }
 633
 634 static void gb_svc_process_intf_hot_unplug(struct gb_operation *operation)
 635 {
 636         struct gb_svc *svc = gb_connection_get_data(operation->connection);
 637         struct gb_svc_intf_hot_unplug_request *request;
 638         struct gb_host_device *hd = operation->connection->hd;
 639         struct gb_interface *intf;
 640         u8 intf_id;
 641
 642         /* The request message size has already been verified. */
 643         request = operation->request->payload;
 644         intf_id = request->intf_id;
 645
 646         dev_dbg(&svc->dev, "%s - id = %u\n", __func__, intf_id);
 647
 648         intf = gb_interface_find(hd, intf_id);
 649         if (!intf) {
 650                 dev_warn(&svc->dev, "could not find hot-unplug interface %u\n",
 651                                 intf_id);
 652                 return;
 653         }
 654
 655         gb_svc_intf_remove(svc, intf);
 656 }
 657
 658 static void gb_svc_process_deferred_request(struct work_struct *work)
 659 {
 660         struct gb_svc_deferred_request *dr;
 661         struct gb_operation *operation;
 662         struct gb_svc *svc;
 663         u8 type;
 664
 665         dr = container_of(work, struct gb_svc_deferred_request, work);
 666         operation = dr->operation;
 667         svc = gb_connection_get_data(operation->connection);
 668         type = operation->request->header->type;
 669
 670         switch (type) {
 671         case GB_SVC_TYPE_INTF_HOTPLUG:
 672                 gb_svc_process_intf_hotplug(operation);
 673                 break;
 674         case GB_SVC_TYPE_INTF_HOT_UNPLUG:
 675                 gb_svc_process_intf_hot_unplug(operation);
 676                 break;
 677         default:
 678                 dev_err(&svc->dev, "bad deferred request type: 0x%02x\n", type);
 679         }
 680
 681         gb_operation_put(operation);
 682         kfree(dr);
 683 }
 684
 685 static int gb_svc_queue_deferred_request(struct gb_operation *operation)
 686 {
 687         struct gb_svc *svc = gb_connection_get_data(operation->connection);
 688         struct gb_svc_deferred_request *dr;
 689
 690         dr = kmalloc(sizeof(*dr), GFP_KERNEL);
 691         if (!dr)
 692                 return -ENOMEM;
 693
 694         gb_operation_get(operation);
 695
 696         dr->operation = operation;
 697         INIT_WORK(&dr->work, gb_svc_process_deferred_request);
 698
 699         queue_work(svc->wq, &dr->work);
 700
 701         return 0;
 702 }
 703
 704 /*
 705  * Bringing up a module can be time consuming, as that may require lots of
 706  * initialization on the module side. Over that, we may also need to download
 707  * the firmware first and flash that on the module.
 708  *
 709  * In order not to make other svc events wait for all this to finish,
 710  * handle most of module hotplug stuff outside of the hotplug callback, with
 711  * help of a workqueue.
 712  */
 713 static int gb_svc_intf_hotplug_recv(struct gb_operation *op)
 714 {
 715         struct gb_svc *svc = gb_connection_get_data(op->connection);
 716         struct gb_svc_intf_hotplug_request *request;
 717
 718         if (op->request->payload_size < sizeof(*request)) {
 719                 dev_warn(&svc->dev, "short hotplug request received (%zu < %zu)\n",
 720                                 op->request->payload_size, sizeof(*request));
 721                 return -EINVAL;
 722         }
 723
 724         request = op->request->payload;
 725
 726         dev_dbg(&svc->dev, "%s - id = %u\n", __func__, request->intf_id);
 727
 728         return gb_svc_queue_deferred_request(op);
 729 }
 730
 731 static int gb_svc_intf_hot_unplug_recv(struct gb_operation *op)
 732 {
 733         struct gb_svc *svc = gb_connection_get_data(op->connection);
 734         struct gb_svc_intf_hot_unplug_request *request;
 735
 736         if (op->request->payload_size < sizeof(*request)) {
 737                 dev_warn(&svc->dev, "short hot unplug request received (%zu < %zu)\n",
 738                                 op->request->payload_size, sizeof(*request));
 739                 return -EINVAL;
 740         }
 741
 742         request = op->request->payload;
 743
 744         dev_dbg(&svc->dev, "%s - id = %u\n", __func__, request->intf_id);
 745
 746         return gb_svc_queue_deferred_request(op);
 747 }
 748
 749 static int gb_svc_intf_reset_recv(struct gb_operation *op)
 750 {
 751         struct gb_svc *svc = gb_connection_get_data(op->connection);
 752         struct gb_message *request = op->request;
 753         struct gb_svc_intf_reset_request *reset;
 754         u8 intf_id;
 755
 756         if (request->payload_size < sizeof(*reset)) {
 757                 dev_warn(&svc->dev, "short reset request received (%zu < %zu)\n",
 758                                 request->payload_size, sizeof(*reset));
 759                 return -EINVAL;
 760         }
 761         reset = request->payload;
 762
 763         intf_id = reset->intf_id;
 764
 765         /* FIXME Reset the interface here */
 766
 767         return 0;
 768 }
 769
 770 static int gb_svc_key_code_map(struct gb_svc *svc, u16 key_code, u16 *code)
 771 {
 772         switch (key_code) {
 773         case GB_KEYCODE_ARA:
 774                 *code = SVC_KEY_ARA_BUTTON;
 775                 break;
 776         default:
 777                 dev_warn(&svc->dev, "unknown keycode received: %u\n", key_code);
 778                 return -EINVAL;
 779         }
 780
 781         return 0;
 782 }
 783
 784 static int gb_svc_key_event_recv(struct gb_operation *op)
 785 {
 786         struct gb_svc *svc = gb_connection_get_data(op->connection);
 787         struct gb_message *request = op->request;
 788         struct gb_svc_key_event_request *key;
 789         u16 code;
 790         u8 event;
 791         int ret;
 792
 793         if (request->payload_size < sizeof(*key)) {
 794                 dev_warn(&svc->dev, "short key request received (%zu < %zu)\n",
 795                          request->payload_size, sizeof(*key));
 796                 return -EINVAL;
 797         }
 798
 799         key = request->payload;
 800
 801         ret = gb_svc_key_code_map(svc, le16_to_cpu(key->key_code), &code);
 802         if (ret < 0)
 803                 return ret;
 804
 805         event = key->key_event;
 806         if ((event != GB_SVC_KEY_PRESSED) && (event != GB_SVC_KEY_RELEASED)) {
 807                 dev_warn(&svc->dev, "unknown key event received: %u\n", event);
 808                 return -EINVAL;
 809         }
 810
 811         input_report_key(svc->input, code, (event == GB_SVC_KEY_PRESSED));
 812         input_sync(svc->input);
 813
 814         return 0;
 815 }
 816
 817 static int gb_svc_request_handler(struct gb_operation *op)
 818 {
 819         struct gb_connection *connection = op->connection;
 820         struct gb_svc *svc = gb_connection_get_data(connection);
 821         u8 type = op->type;
 822         int ret = 0;
 823
 824         /*
 825          * SVC requests need to follow a specific order (at least initially) and
 826          * below code takes care of enforcing that. The expected order is:
 827          * - PROTOCOL_VERSION
 828          * - SVC_HELLO
 829          * - Any other request, but the earlier two.
 830          *
 831          * Incoming requests are guaranteed to be serialized and so we don't
 832          * need to protect 'state' for any races.
 833          */
 834         switch (type) {
 835         case GB_REQUEST_TYPE_PROTOCOL_VERSION:
 836                 if (svc->state != GB_SVC_STATE_RESET)
 837                         ret = -EINVAL;
 838                 break;
 839         case GB_SVC_TYPE_SVC_HELLO:
 840                 if (svc->state != GB_SVC_STATE_PROTOCOL_VERSION)
 841                         ret = -EINVAL;
 842                 break;
 843         default:
 844                 if (svc->state != GB_SVC_STATE_SVC_HELLO)
 845                         ret = -EINVAL;
 846                 break;
 847         }
 848
 849         if (ret) {
 850                 dev_warn(&svc->dev, "unexpected request 0x%02x received (state %u)\n",
 851                                 type, svc->state);
 852                 return ret;
 853         }
 854
 855         switch (type) {
 856         case GB_REQUEST_TYPE_PROTOCOL_VERSION:
 857                 ret = gb_svc_version_request(op);
 858                 if (!ret)
 859                         svc->state = GB_SVC_STATE_PROTOCOL_VERSION;
 860                 return ret;
 861         case GB_SVC_TYPE_SVC_HELLO:
 862                 ret = gb_svc_hello(op);
 863                 if (!ret)
 864                         svc->state = GB_SVC_STATE_SVC_HELLO;
 865                 return ret;
 866         case GB_SVC_TYPE_INTF_HOTPLUG:
 867                 return gb_svc_intf_hotplug_recv(op);
 868         case GB_SVC_TYPE_INTF_HOT_UNPLUG:
 869                 return gb_svc_intf_hot_unplug_recv(op);
 870         case GB_SVC_TYPE_INTF_RESET:
 871                 return gb_svc_intf_reset_recv(op);
 872         case GB_SVC_TYPE_KEY_EVENT:
 873                 return gb_svc_key_event_recv(op);
 874         default:
 875                 dev_warn(&svc->dev, "unsupported request 0x%02x\n", type);
 876                 return -EINVAL;
 877         }
 878 }
 879
 880 static struct input_dev *gb_svc_input_create(struct gb_svc *svc)
 881 {
 882         struct input_dev *input_dev;
 883
 884         input_dev = input_allocate_device();
 885         if (!input_dev)
 886                 return ERR_PTR(-ENOMEM);
 887
 888         input_dev->name = dev_name(&svc->dev);
 889         svc->input_phys = kasprintf(GFP_KERNEL, "greybus-%s/input0",
 890                                     input_dev->name);
 891         if (!svc->input_phys)
 892                 goto err_free_input;
 893
 894         input_dev->phys = svc->input_phys;
 895         input_dev->dev.parent = &svc->dev;
 896
 897         input_set_drvdata(input_dev, svc);
 898
 899         input_set_capability(input_dev, EV_KEY, SVC_KEY_ARA_BUTTON);
 900
 901         return input_dev;
 902
 903 err_free_input:
 904         input_free_device(svc->input);
 905         return ERR_PTR(-ENOMEM);
 906 }
 907
 908 static void gb_svc_release(struct device *dev)
 909 {
 910         struct gb_svc *svc = to_gb_svc(dev);
 911
 912         if (svc->connection)
 913                 gb_connection_destroy(svc->connection);
 914         ida_destroy(&svc->device_id_map);
 915         destroy_workqueue(svc->wq);
 916         kfree(svc->input_phys);
 917         kfree(svc);
 918 }
 919
 920 struct device_type greybus_svc_type = {
 921         .name           = "greybus_svc",
 922         .release        = gb_svc_release,
 923 };
 924
 925 struct gb_svc *gb_svc_create(struct gb_host_device *hd)
 926 {
 927         struct gb_svc *svc;
 928
 929         svc = kzalloc(sizeof(*svc), GFP_KERNEL);
 930         if (!svc)
 931                 return NULL;
 932
 933         svc->wq = alloc_workqueue("%s:svc", WQ_UNBOUND, 1, dev_name(&hd->dev));
 934         if (!svc->wq) {
 935                 kfree(svc);
 936                 return NULL;
 937         }
 938
 939         svc->dev.parent = &hd->dev;
 940         svc->dev.bus = &greybus_bus_type;
 941         svc->dev.type = &greybus_svc_type;
 942         svc->dev.groups = svc_groups;
 943         svc->dev.dma_mask = svc->dev.parent->dma_mask;
 944         device_initialize(&svc->dev);
 945
 946         dev_set_name(&svc->dev, "%d-svc", hd->bus_id);
 947
 948         ida_init(&svc->device_id_map);
 949         svc->state = GB_SVC_STATE_RESET;
 950         svc->hd = hd;
 951
 952         svc->input = gb_svc_input_create(svc);
 953         if (IS_ERR(svc->input)) {
 954                 dev_err(&svc->dev, "failed to create input device: %ld\n",
 955                         PTR_ERR(svc->input));
 956                 goto err_put_device;
 957         }
 958
 959         svc->connection = gb_connection_create_static(hd, GB_SVC_CPORT_ID,
 960                                                 gb_svc_request_handler);
 961         if (IS_ERR(svc->connection)) {
 962                 dev_err(&svc->dev, "failed to create connection: %ld\n",
 963                                 PTR_ERR(svc->connection));
 964                 goto err_free_input;
 965         }
 966
 967         gb_connection_set_data(svc->connection, svc);
 968
 969         return svc;
 970
 971 err_free_input:
 972         input_free_device(svc->input);
 973 err_put_device:
 974         put_device(&svc->dev);
 975         return NULL;
 976 }
 977
 978 int gb_svc_add(struct gb_svc *svc)
 979 {
 980         int ret;
 981
 982         /*
 983          * The SVC protocol is currently driven by the SVC, so the SVC device
 984          * is added from the connection request handler when enough
 985          * information has been received.
 986          */
 987         ret = gb_connection_enable(svc->connection);
 988         if (ret)
 989                 return ret;
 990
 991         return 0;
 992 }
 993
 994 static void gb_svc_remove_interfaces(struct gb_svc *svc)
 995 {
 996         struct gb_interface *intf, *tmp;
 997
 998         list_for_each_entry_safe(intf, tmp, &svc->hd->interfaces, links) {
 999                 gb_interface_disable(intf);
1000                 gb_interface_remove(intf);
1001         }
1002 }
1003
1004 void gb_svc_del(struct gb_svc *svc)
1005 {
1006         gb_connection_disable(svc->connection);
1007
1008         /*
1009          * The SVC device and input device may have been registered
1010          * from the request handler.
1011          */
1012         if (device_is_registered(&svc->dev)) {
1013                 gb_svc_watchdog_destroy(svc);
1014                 input_unregister_device(svc->input);
1015                 device_del(&svc->dev);
1016         }
1017
1018         flush_workqueue(svc->wq);
1019
1020         gb_svc_remove_interfaces(svc);
1021 }
1022
1023 void gb_svc_put(struct gb_svc *svc)
1024 {
1025         put_device(&svc->dev);
1026 }