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