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_reset(struct gb_svc *svc, u8 intf_id)
 123 {
 124         struct gb_svc_intf_reset_request request;
 125
 126         request.intf_id = intf_id;
 127
 128         return gb_operation_sync(svc->connection, GB_SVC_TYPE_INTF_RESET,
 129                                  &request, sizeof(request), NULL, 0);
 130 }
 131 EXPORT_SYMBOL_GPL(gb_svc_intf_reset);
 132
 133 int gb_svc_intf_eject(struct gb_svc *svc, u8 intf_id)
 134 {
 135         struct gb_svc_intf_eject_request request;
 136         int ret;
 137
 138         request.intf_id = intf_id;
 139
 140         /*
 141          * The pulse width for module release in svc is long so we need to
 142          * increase the timeout so the operation will not return to soon.
 143          */
 144         ret = gb_operation_sync_timeout(svc->connection,
 145                                         GB_SVC_TYPE_INTF_EJECT, &request,
 146                                         sizeof(request), NULL, 0,
 147                                         SVC_INTF_EJECT_TIMEOUT);
 148         if (ret) {
 149                 dev_err(&svc->dev, "failed to eject interface %u\n", intf_id);
 150                 return ret;
 151         }
 152
 153         return 0;
 154 }
 155
 156 int gb_svc_dme_peer_get(struct gb_svc *svc, u8 intf_id, u16 attr, u16 selector,
 157                         u32 *value)
 158 {
 159         struct gb_svc_dme_peer_get_request request;
 160         struct gb_svc_dme_peer_get_response response;
 161         u16 result;
 162         int ret;
 163
 164         request.intf_id = intf_id;
 165         request.attr = cpu_to_le16(attr);
 166         request.selector = cpu_to_le16(selector);
 167
 168         ret = gb_operation_sync(svc->connection, GB_SVC_TYPE_DME_PEER_GET,
 169                                 &request, sizeof(request),
 170                                 &response, sizeof(response));
 171         if (ret) {
 172                 dev_err(&svc->dev, "failed to get DME attribute (%u 0x%04x %u): %d\n",
 173                                 intf_id, attr, selector, ret);
 174                 return ret;
 175         }
 176
 177         result = le16_to_cpu(response.result_code);
 178         if (result) {
 179                 dev_err(&svc->dev, "UniPro error while getting DME attribute (%u 0x%04x %u): %u\n",
 180                                 intf_id, attr, selector, result);
 181                 return -EIO;
 182         }
 183
 184         if (value)
 185                 *value = le32_to_cpu(response.attr_value);
 186
 187         return 0;
 188 }
 189 EXPORT_SYMBOL_GPL(gb_svc_dme_peer_get);
 190
 191 int gb_svc_dme_peer_set(struct gb_svc *svc, u8 intf_id, u16 attr, u16 selector,
 192                         u32 value)
 193 {
 194         struct gb_svc_dme_peer_set_request request;
 195         struct gb_svc_dme_peer_set_response response;
 196         u16 result;
 197         int ret;
 198
 199         request.intf_id = intf_id;
 200         request.attr = cpu_to_le16(attr);
 201         request.selector = cpu_to_le16(selector);
 202         request.value = cpu_to_le32(value);
 203
 204         ret = gb_operation_sync(svc->connection, GB_SVC_TYPE_DME_PEER_SET,
 205                                 &request, sizeof(request),
 206                                 &response, sizeof(response));
 207         if (ret) {
 208                 dev_err(&svc->dev, "failed to set DME attribute (%u 0x%04x %u %u): %d\n",
 209                                 intf_id, attr, selector, value, ret);
 210                 return ret;
 211         }
 212
 213         result = le16_to_cpu(response.result_code);
 214         if (result) {
 215                 dev_err(&svc->dev, "UniPro error while setting DME attribute (%u 0x%04x %u %u): %u\n",
 216                                 intf_id, attr, selector, value, result);
 217                 return -EIO;
 218         }
 219
 220         return 0;
 221 }
 222 EXPORT_SYMBOL_GPL(gb_svc_dme_peer_set);
 223
 224 /*
 225  * T_TstSrcIncrement is written by the module on ES2 as a stand-in for boot
 226  * status attribute ES3_INIT_STATUS. AP needs to read and clear it, after
 227  * reading a non-zero value from it.
 228  *
 229  * FIXME: This is module-hardware dependent and needs to be extended for every
 230  * type of module we want to support.
 231  */
 232 static int gb_svc_read_and_clear_module_boot_status(struct gb_interface *intf)
 233 {
 234         struct gb_host_device *hd = intf->hd;
 235         int ret;
 236         u32 value;
 237         u16 attr;
 238         u8 init_status;
 239
 240         /*
 241          * Check if the module is ES2 or ES3, and choose attr number
 242          * appropriately.
 243          * FIXME: Remove ES2 support from the kernel entirely.
 244          */
 245         if (intf->ddbl1_manufacturer_id == ES2_DDBL1_MFR_ID &&
 246                                 intf->ddbl1_product_id == ES2_DDBL1_PROD_ID)
 247                 attr = DME_ATTR_T_TST_SRC_INCREMENT;
 248         else
 249                 attr = DME_ATTR_ES3_INIT_STATUS;
 250
 251         /* Read and clear boot status in ES3_INIT_STATUS */
 252         ret = gb_svc_dme_peer_get(hd->svc, intf->interface_id, attr,
 253                                   DME_ATTR_SELECTOR_INDEX, &value);
 254
 255         if (ret)
 256                 return ret;
 257
 258         /*
 259          * A nonzero boot status indicates the module has finished
 260          * booting. Clear it.
 261          */
 262         if (!value) {
 263                 dev_err(&intf->dev, "Module not ready yet\n");
 264                 return -ENODEV;
 265         }
 266
 267         /*
 268          * Check if the module needs to boot from UniPro.
 269          * For ES2: We need to check lowest 8 bits of 'value'.
 270          * For ES3: We need to check highest 8 bits out of 32 of 'value'.
 271          * FIXME: Remove ES2 support from the kernel entirely.
 272          */
 273         if (intf->ddbl1_manufacturer_id == ES2_DDBL1_MFR_ID &&
 274                                 intf->ddbl1_product_id == ES2_DDBL1_PROD_ID)
 275                 init_status = value;
 276         else
 277                 init_status = value >> 24;
 278
 279         if (init_status == DME_DIS_UNIPRO_BOOT_STARTED ||
 280                                 init_status == DME_DIS_FALLBACK_UNIPRO_BOOT_STARTED)
 281                 intf->boot_over_unipro = true;
 282
 283         return gb_svc_dme_peer_set(hd->svc, intf->interface_id, attr,
 284                                    DME_ATTR_SELECTOR_INDEX, 0);
 285 }
 286
 287 int gb_svc_connection_create(struct gb_svc *svc,
 288                                 u8 intf1_id, u16 cport1_id,
 289                                 u8 intf2_id, u16 cport2_id,
 290                                 u8 cport_flags)
 291 {
 292         struct gb_svc_conn_create_request request;
 293
 294         request.intf1_id = intf1_id;
 295         request.cport1_id = cpu_to_le16(cport1_id);
 296         request.intf2_id = intf2_id;
 297         request.cport2_id = cpu_to_le16(cport2_id);
 298         request.tc = 0;         /* TC0 */
 299         request.flags = cport_flags;
 300
 301         return gb_operation_sync(svc->connection, GB_SVC_TYPE_CONN_CREATE,
 302                                  &request, sizeof(request), NULL, 0);
 303 }
 304 EXPORT_SYMBOL_GPL(gb_svc_connection_create);
 305
 306 void gb_svc_connection_destroy(struct gb_svc *svc, u8 intf1_id, u16 cport1_id,
 307                                u8 intf2_id, u16 cport2_id)
 308 {
 309         struct gb_svc_conn_destroy_request request;
 310         struct gb_connection *connection = svc->connection;
 311         int ret;
 312
 313         request.intf1_id = intf1_id;
 314         request.cport1_id = cpu_to_le16(cport1_id);
 315         request.intf2_id = intf2_id;
 316         request.cport2_id = cpu_to_le16(cport2_id);
 317
 318         ret = gb_operation_sync(connection, GB_SVC_TYPE_CONN_DESTROY,
 319                                 &request, sizeof(request), NULL, 0);
 320         if (ret) {
 321                 dev_err(&svc->dev, "failed to destroy connection (%u:%u %u:%u): %d\n",
 322                                 intf1_id, cport1_id, intf2_id, cport2_id, ret);
 323         }
 324 }
 325 EXPORT_SYMBOL_GPL(gb_svc_connection_destroy);
 326
 327 /* Creates bi-directional routes between the devices */
 328 static int gb_svc_route_create(struct gb_svc *svc, u8 intf1_id, u8 dev1_id,
 329                                u8 intf2_id, u8 dev2_id)
 330 {
 331         struct gb_svc_route_create_request request;
 332
 333         request.intf1_id = intf1_id;
 334         request.dev1_id = dev1_id;
 335         request.intf2_id = intf2_id;
 336         request.dev2_id = dev2_id;
 337
 338         return gb_operation_sync(svc->connection, GB_SVC_TYPE_ROUTE_CREATE,
 339                                  &request, sizeof(request), NULL, 0);
 340 }
 341
 342 /* Destroys bi-directional routes between the devices */
 343 static void gb_svc_route_destroy(struct gb_svc *svc, u8 intf1_id, u8 intf2_id)
 344 {
 345         struct gb_svc_route_destroy_request request;
 346         int ret;
 347
 348         request.intf1_id = intf1_id;
 349         request.intf2_id = intf2_id;
 350
 351         ret = gb_operation_sync(svc->connection, GB_SVC_TYPE_ROUTE_DESTROY,
 352                                 &request, sizeof(request), NULL, 0);
 353         if (ret) {
 354                 dev_err(&svc->dev, "failed to destroy route (%u %u): %d\n",
 355                                 intf1_id, intf2_id, ret);
 356         }
 357 }
 358
 359 int gb_svc_intf_set_power_mode(struct gb_svc *svc, u8 intf_id, u8 hs_series,
 360                                u8 tx_mode, u8 tx_gear, u8 tx_nlanes,
 361                                u8 rx_mode, u8 rx_gear, u8 rx_nlanes,
 362                                u8 flags, u32 quirks)
 363 {
 364         struct gb_svc_intf_set_pwrm_request request;
 365         struct gb_svc_intf_set_pwrm_response response;
 366         int ret;
 367
 368         request.intf_id = intf_id;
 369         request.hs_series = hs_series;
 370         request.tx_mode = tx_mode;
 371         request.tx_gear = tx_gear;
 372         request.tx_nlanes = tx_nlanes;
 373         request.rx_mode = rx_mode;
 374         request.rx_gear = rx_gear;
 375         request.rx_nlanes = rx_nlanes;
 376         request.flags = flags;
 377         request.quirks = cpu_to_le32(quirks);
 378
 379         ret = gb_operation_sync(svc->connection, GB_SVC_TYPE_INTF_SET_PWRM,
 380                                 &request, sizeof(request),
 381                                 &response, sizeof(response));
 382         if (ret < 0)
 383                 return ret;
 384
 385         return le16_to_cpu(response.result_code);
 386 }
 387 EXPORT_SYMBOL_GPL(gb_svc_intf_set_power_mode);
 388
 389 int gb_svc_ping(struct gb_svc *svc)
 390 {
 391         return gb_operation_sync_timeout(svc->connection, GB_SVC_TYPE_PING,
 392                                          NULL, 0, NULL, 0,
 393                                          GB_OPERATION_TIMEOUT_DEFAULT * 2);
 394 }
 395 EXPORT_SYMBOL_GPL(gb_svc_ping);
 396
 397 static int gb_svc_version_request(struct gb_operation *op)
 398 {
 399         struct gb_connection *connection = op->connection;
 400         struct gb_svc *svc = gb_connection_get_data(connection);
 401         struct gb_protocol_version_request *request;
 402         struct gb_protocol_version_response *response;
 403
 404         if (op->request->payload_size < sizeof(*request)) {
 405                 dev_err(&svc->dev, "short version request (%zu < %zu)\n",
 406                                 op->request->payload_size,
 407                                 sizeof(*request));
 408                 return -EINVAL;
 409         }
 410
 411         request = op->request->payload;
 412
 413         if (request->major > GB_SVC_VERSION_MAJOR) {
 414                 dev_warn(&svc->dev, "unsupported major version (%u > %u)\n",
 415                                 request->major, GB_SVC_VERSION_MAJOR);
 416                 return -ENOTSUPP;
 417         }
 418
 419         svc->protocol_major = request->major;
 420         svc->protocol_minor = request->minor;
 421
 422         if (!gb_operation_response_alloc(op, sizeof(*response), GFP_KERNEL))
 423                 return -ENOMEM;
 424
 425         response = op->response->payload;
 426         response->major = svc->protocol_major;
 427         response->minor = svc->protocol_minor;
 428
 429         return 0;
 430 }
 431
 432 static int gb_svc_hello(struct gb_operation *op)
 433 {
 434         struct gb_connection *connection = op->connection;
 435         struct gb_svc *svc = gb_connection_get_data(connection);
 436         struct gb_svc_hello_request *hello_request;
 437         int ret;
 438
 439         if (op->request->payload_size < sizeof(*hello_request)) {
 440                 dev_warn(&svc->dev, "short hello request (%zu < %zu)\n",
 441                                 op->request->payload_size,
 442                                 sizeof(*hello_request));
 443                 return -EINVAL;
 444         }
 445
 446         hello_request = op->request->payload;
 447         svc->endo_id = le16_to_cpu(hello_request->endo_id);
 448         svc->ap_intf_id = hello_request->interface_id;
 449
 450         ret = device_add(&svc->dev);
 451         if (ret) {
 452                 dev_err(&svc->dev, "failed to register svc device: %d\n", ret);
 453                 return ret;
 454         }
 455
 456         ret = input_register_device(svc->input);
 457         if (ret) {
 458                 dev_err(&svc->dev, "failed to register input: %d\n", ret);
 459                 device_del(&svc->dev);
 460                 return ret;
 461         }
 462
 463         ret = gb_svc_watchdog_create(svc);
 464         if (ret) {
 465                 dev_err(&svc->dev, "failed to create watchdog: %d\n", ret);
 466                 input_unregister_device(svc->input);
 467                 device_del(&svc->dev);
 468                 return ret;
 469         }
 470
 471         return 0;
 472 }
 473
 474 static int gb_svc_interface_route_create(struct gb_svc *svc,
 475                                                 struct gb_interface *intf)
 476 {
 477         u8 intf_id = intf->interface_id;
 478         u8 device_id;
 479         int ret;
 480
 481         /*
 482          * Create a device id for the interface:
 483          * - device id 0 (GB_DEVICE_ID_SVC) belongs to the SVC
 484          * - device id 1 (GB_DEVICE_ID_AP) belongs to the AP
 485          *
 486          * XXX Do we need to allocate device ID for SVC or the AP here? And what
 487          * XXX about an AP with multiple interface blocks?
 488          */
 489         ret = ida_simple_get(&svc->device_id_map,
 490                              GB_DEVICE_ID_MODULES_START, 0, GFP_KERNEL);
 491         if (ret < 0) {
 492                 dev_err(&svc->dev, "failed to allocate device id for interface %u: %d\n",
 493                                 intf_id, ret);
 494                 return ret;
 495         }
 496         device_id = ret;
 497
 498         ret = gb_svc_intf_device_id(svc, intf_id, device_id);
 499         if (ret) {
 500                 dev_err(&svc->dev, "failed to set device id %u for interface %u: %d\n",
 501                                 device_id, intf_id, ret);
 502                 goto err_ida_remove;
 503         }
 504
 505         /* Create a two-way route between the AP and the new interface. */
 506         ret = gb_svc_route_create(svc, svc->ap_intf_id, GB_DEVICE_ID_AP,
 507                                   intf_id, device_id);
 508         if (ret) {
 509                 dev_err(&svc->dev, "failed to create route to interface %u (device id %u): %d\n",
 510                                 intf_id, device_id, ret);
 511                 goto err_svc_id_free;
 512         }
 513
 514         intf->device_id = device_id;
 515
 516         return 0;
 517
 518 err_svc_id_free:
 519         /*
 520          * XXX Should we tell SVC that this id doesn't belong to interface
 521          * XXX anymore.
 522          */
 523 err_ida_remove:
 524         ida_simple_remove(&svc->device_id_map, device_id);
 525
 526         return ret;
 527 }
 528
 529 static void gb_svc_interface_route_destroy(struct gb_svc *svc,
 530                                                 struct gb_interface *intf)
 531 {
 532         if (intf->device_id == GB_DEVICE_ID_BAD)
 533                 return;
 534
 535         gb_svc_route_destroy(svc, svc->ap_intf_id, intf->interface_id);
 536         ida_simple_remove(&svc->device_id_map, intf->device_id);
 537         intf->device_id = GB_DEVICE_ID_BAD;
 538 }
 539
 540 static void gb_svc_intf_remove(struct gb_svc *svc, struct gb_interface *intf)
 541 {
 542         intf->disconnected = true;
 543
 544         gb_interface_disable(intf);
 545         gb_svc_interface_route_destroy(svc, intf);
 546         gb_interface_remove(intf);
 547 }
 548
 549 static void gb_svc_process_intf_hotplug(struct gb_operation *operation)
 550 {
 551         struct gb_svc_intf_hotplug_request *request;
 552         struct gb_connection *connection = operation->connection;
 553         struct gb_svc *svc = gb_connection_get_data(connection);
 554         struct gb_host_device *hd = connection->hd;
 555         struct gb_interface *intf;
 556         u8 intf_id;
 557         u32 vendor_id = 0;
 558         u32 product_id = 0;
 559         int ret;
 560
 561         /* The request message size has already been verified. */
 562         request = operation->request->payload;
 563         intf_id = request->intf_id;
 564
 565         dev_dbg(&svc->dev, "%s - id = %u\n", __func__, intf_id);
 566
 567         intf = gb_interface_find(hd, intf_id);
 568         if (intf) {
 569                 /*
 570                  * For ES2, we need to maintain the same vendor/product ids we
 571                  * got from bootrom, otherwise userspace can't distinguish
 572                  * between modules.
 573                  */
 574                 vendor_id = intf->vendor_id;
 575                 product_id = intf->product_id;
 576
 577                 /*
 578                  * We have received a hotplug request for an interface that
 579                  * already exists.
 580                  *
 581                  * This can happen in cases like:
 582                  * - bootrom loading the firmware image and booting into that,
 583                  *   which only generates a hotplug event. i.e. no hot-unplug
 584                  *   event.
 585                  * - Or the firmware on the module crashed and sent hotplug
 586                  *   request again to the SVC, which got propagated to AP.
 587                  *
 588                  * Remove the interface and add it again, and let user know
 589                  * about this with a print message.
 590                  */
 591                 dev_info(&svc->dev, "removing interface %u to add it again\n",
 592                                 intf_id);
 593                 gb_svc_intf_remove(svc, intf);
 594         }
 595
 596         intf = gb_interface_create(hd, intf_id);
 597         if (!intf) {
 598                 dev_err(&svc->dev, "failed to create interface %u\n",
 599                                 intf_id);
 600                 return;
 601         }
 602
 603         intf->ddbl1_manufacturer_id = le32_to_cpu(request->data.ddbl1_mfr_id);
 604         intf->ddbl1_product_id = le32_to_cpu(request->data.ddbl1_prod_id);
 605         intf->vendor_id = le32_to_cpu(request->data.ara_vend_id);
 606         intf->product_id = le32_to_cpu(request->data.ara_prod_id);
 607         intf->serial_number = le64_to_cpu(request->data.serial_number);
 608
 609         /*
 610          * Use VID/PID specified at hotplug if:
 611          * - Bridge ASIC chip isn't ES2
 612          * - Received non-zero Vendor/Product ids
 613          *
 614          * Otherwise, use the ids we received from bootrom.
 615          */
 616         if (intf->ddbl1_manufacturer_id == ES2_DDBL1_MFR_ID &&
 617             intf->ddbl1_product_id == ES2_DDBL1_PROD_ID &&
 618             intf->vendor_id == 0 && intf->product_id == 0) {
 619                 intf->vendor_id = vendor_id;
 620                 intf->product_id = product_id;
 621         }
 622
 623         ret = gb_svc_read_and_clear_module_boot_status(intf);
 624         if (ret) {
 625                 dev_err(&svc->dev, "failed to clear boot status of interface %u: %d\n",
 626                                 intf_id, ret);
 627                 goto out_interface_add;
 628         }
 629
 630         ret = gb_svc_interface_route_create(svc, intf);
 631         if (ret)
 632                 goto out_interface_add;
 633
 634         ret = gb_interface_enable(intf);
 635         if (ret) {
 636                 dev_err(&svc->dev, "failed to enable interface %u: %d\n",
 637                                 intf_id, ret);
 638                 goto out_interface_add;
 639         }
 640
 641 out_interface_add:
 642         gb_interface_add(intf);
 643 }
 644
 645 static void gb_svc_process_intf_hot_unplug(struct gb_operation *operation)
 646 {
 647         struct gb_svc *svc = gb_connection_get_data(operation->connection);
 648         struct gb_svc_intf_hot_unplug_request *request;
 649         struct gb_host_device *hd = operation->connection->hd;
 650         struct gb_interface *intf;
 651         u8 intf_id;
 652
 653         /* The request message size has already been verified. */
 654         request = operation->request->payload;
 655         intf_id = request->intf_id;
 656
 657         dev_dbg(&svc->dev, "%s - id = %u\n", __func__, intf_id);
 658
 659         intf = gb_interface_find(hd, intf_id);
 660         if (!intf) {
 661                 dev_warn(&svc->dev, "could not find hot-unplug interface %u\n",
 662                                 intf_id);
 663                 return;
 664         }
 665
 666         gb_svc_intf_remove(svc, intf);
 667 }
 668
 669 static void gb_svc_process_deferred_request(struct work_struct *work)
 670 {
 671         struct gb_svc_deferred_request *dr;
 672         struct gb_operation *operation;
 673         struct gb_svc *svc;
 674         u8 type;
 675
 676         dr = container_of(work, struct gb_svc_deferred_request, work);
 677         operation = dr->operation;
 678         svc = gb_connection_get_data(operation->connection);
 679         type = operation->request->header->type;
 680
 681         switch (type) {
 682         case GB_SVC_TYPE_INTF_HOTPLUG:
 683                 gb_svc_process_intf_hotplug(operation);
 684                 break;
 685         case GB_SVC_TYPE_INTF_HOT_UNPLUG:
 686                 gb_svc_process_intf_hot_unplug(operation);
 687                 break;
 688         default:
 689                 dev_err(&svc->dev, "bad deferred request type: 0x%02x\n", type);
 690         }
 691
 692         gb_operation_put(operation);
 693         kfree(dr);
 694 }
 695
 696 static int gb_svc_queue_deferred_request(struct gb_operation *operation)
 697 {
 698         struct gb_svc *svc = gb_connection_get_data(operation->connection);
 699         struct gb_svc_deferred_request *dr;
 700
 701         dr = kmalloc(sizeof(*dr), GFP_KERNEL);
 702         if (!dr)
 703                 return -ENOMEM;
 704
 705         gb_operation_get(operation);
 706
 707         dr->operation = operation;
 708         INIT_WORK(&dr->work, gb_svc_process_deferred_request);
 709
 710         queue_work(svc->wq, &dr->work);
 711
 712         return 0;
 713 }
 714
 715 /*
 716  * Bringing up a module can be time consuming, as that may require lots of
 717  * initialization on the module side. Over that, we may also need to download
 718  * the firmware first and flash that on the module.
 719  *
 720  * In order not to make other svc events wait for all this to finish,
 721  * handle most of module hotplug stuff outside of the hotplug callback, with
 722  * help of a workqueue.
 723  */
 724 static int gb_svc_intf_hotplug_recv(struct gb_operation *op)
 725 {
 726         struct gb_svc *svc = gb_connection_get_data(op->connection);
 727         struct gb_svc_intf_hotplug_request *request;
 728
 729         if (op->request->payload_size < sizeof(*request)) {
 730                 dev_warn(&svc->dev, "short hotplug request received (%zu < %zu)\n",
 731                                 op->request->payload_size, sizeof(*request));
 732                 return -EINVAL;
 733         }
 734
 735         request = op->request->payload;
 736
 737         dev_dbg(&svc->dev, "%s - id = %u\n", __func__, request->intf_id);
 738
 739         return gb_svc_queue_deferred_request(op);
 740 }
 741
 742 static int gb_svc_intf_hot_unplug_recv(struct gb_operation *op)
 743 {
 744         struct gb_svc *svc = gb_connection_get_data(op->connection);
 745         struct gb_svc_intf_hot_unplug_request *request;
 746
 747         if (op->request->payload_size < sizeof(*request)) {
 748                 dev_warn(&svc->dev, "short hot unplug request received (%zu < %zu)\n",
 749                                 op->request->payload_size, sizeof(*request));
 750                 return -EINVAL;
 751         }
 752
 753         request = op->request->payload;
 754
 755         dev_dbg(&svc->dev, "%s - id = %u\n", __func__, request->intf_id);
 756
 757         return gb_svc_queue_deferred_request(op);
 758 }
 759
 760 static int gb_svc_intf_reset_recv(struct gb_operation *op)
 761 {
 762         struct gb_svc *svc = gb_connection_get_data(op->connection);
 763         struct gb_message *request = op->request;
 764         struct gb_svc_intf_reset_request *reset;
 765         u8 intf_id;
 766
 767         if (request->payload_size < sizeof(*reset)) {
 768                 dev_warn(&svc->dev, "short reset request received (%zu < %zu)\n",
 769                                 request->payload_size, sizeof(*reset));
 770                 return -EINVAL;
 771         }
 772         reset = request->payload;
 773
 774         intf_id = reset->intf_id;
 775
 776         /* FIXME Reset the interface here */
 777
 778         return 0;
 779 }
 780
 781 static int gb_svc_key_code_map(struct gb_svc *svc, u16 key_code, u16 *code)
 782 {
 783         switch (key_code) {
 784         case GB_KEYCODE_ARA:
 785                 *code = SVC_KEY_ARA_BUTTON;
 786                 break;
 787         default:
 788                 dev_warn(&svc->dev, "unknown keycode received: %u\n", key_code);
 789                 return -EINVAL;
 790         }
 791
 792         return 0;
 793 }
 794
 795 static int gb_svc_key_event_recv(struct gb_operation *op)
 796 {
 797         struct gb_svc *svc = gb_connection_get_data(op->connection);
 798         struct gb_message *request = op->request;
 799         struct gb_svc_key_event_request *key;
 800         u16 code;
 801         u8 event;
 802         int ret;
 803
 804         if (request->payload_size < sizeof(*key)) {
 805                 dev_warn(&svc->dev, "short key request received (%zu < %zu)\n",
 806                          request->payload_size, sizeof(*key));
 807                 return -EINVAL;
 808         }
 809
 810         key = request->payload;
 811
 812         ret = gb_svc_key_code_map(svc, le16_to_cpu(key->key_code), &code);
 813         if (ret < 0)
 814                 return ret;
 815
 816         event = key->key_event;
 817         if ((event != GB_SVC_KEY_PRESSED) && (event != GB_SVC_KEY_RELEASED)) {
 818                 dev_warn(&svc->dev, "unknown key event received: %u\n", event);
 819                 return -EINVAL;
 820         }
 821
 822         input_report_key(svc->input, code, (event == GB_SVC_KEY_PRESSED));
 823         input_sync(svc->input);
 824
 825         return 0;
 826 }
 827
 828 static int gb_svc_request_handler(struct gb_operation *op)
 829 {
 830         struct gb_connection *connection = op->connection;
 831         struct gb_svc *svc = gb_connection_get_data(connection);
 832         u8 type = op->type;
 833         int ret = 0;
 834
 835         /*
 836          * SVC requests need to follow a specific order (at least initially) and
 837          * below code takes care of enforcing that. The expected order is:
 838          * - PROTOCOL_VERSION
 839          * - SVC_HELLO
 840          * - Any other request, but the earlier two.
 841          *
 842          * Incoming requests are guaranteed to be serialized and so we don't
 843          * need to protect 'state' for any races.
 844          */
 845         switch (type) {
 846         case GB_REQUEST_TYPE_PROTOCOL_VERSION:
 847                 if (svc->state != GB_SVC_STATE_RESET)
 848                         ret = -EINVAL;
 849                 break;
 850         case GB_SVC_TYPE_SVC_HELLO:
 851                 if (svc->state != GB_SVC_STATE_PROTOCOL_VERSION)
 852                         ret = -EINVAL;
 853                 break;
 854         default:
 855                 if (svc->state != GB_SVC_STATE_SVC_HELLO)
 856                         ret = -EINVAL;
 857                 break;
 858         }
 859
 860         if (ret) {
 861                 dev_warn(&svc->dev, "unexpected request 0x%02x received (state %u)\n",
 862                                 type, svc->state);
 863                 return ret;
 864         }
 865
 866         switch (type) {
 867         case GB_REQUEST_TYPE_PROTOCOL_VERSION:
 868                 ret = gb_svc_version_request(op);
 869                 if (!ret)
 870                         svc->state = GB_SVC_STATE_PROTOCOL_VERSION;
 871                 return ret;
 872         case GB_SVC_TYPE_SVC_HELLO:
 873                 ret = gb_svc_hello(op);
 874                 if (!ret)
 875                         svc->state = GB_SVC_STATE_SVC_HELLO;
 876                 return ret;
 877         case GB_SVC_TYPE_INTF_HOTPLUG:
 878                 return gb_svc_intf_hotplug_recv(op);
 879         case GB_SVC_TYPE_INTF_HOT_UNPLUG:
 880                 return gb_svc_intf_hot_unplug_recv(op);
 881         case GB_SVC_TYPE_INTF_RESET:
 882                 return gb_svc_intf_reset_recv(op);
 883         case GB_SVC_TYPE_KEY_EVENT:
 884                 return gb_svc_key_event_recv(op);
 885         default:
 886                 dev_warn(&svc->dev, "unsupported request 0x%02x\n", type);
 887                 return -EINVAL;
 888         }
 889 }
 890
 891 static struct input_dev *gb_svc_input_create(struct gb_svc *svc)
 892 {
 893         struct input_dev *input_dev;
 894
 895         input_dev = input_allocate_device();
 896         if (!input_dev)
 897                 return ERR_PTR(-ENOMEM);
 898
 899         input_dev->name = dev_name(&svc->dev);
 900         svc->input_phys = kasprintf(GFP_KERNEL, "greybus-%s/input0",
 901                                     input_dev->name);
 902         if (!svc->input_phys)
 903                 goto err_free_input;
 904
 905         input_dev->phys = svc->input_phys;
 906         input_dev->dev.parent = &svc->dev;
 907
 908         input_set_drvdata(input_dev, svc);
 909
 910         input_set_capability(input_dev, EV_KEY, SVC_KEY_ARA_BUTTON);
 911
 912         return input_dev;
 913
 914 err_free_input:
 915         input_free_device(svc->input);
 916         return ERR_PTR(-ENOMEM);
 917 }
 918
 919 static void gb_svc_release(struct device *dev)
 920 {
 921         struct gb_svc *svc = to_gb_svc(dev);
 922
 923         if (svc->connection)
 924                 gb_connection_destroy(svc->connection);
 925         ida_destroy(&svc->device_id_map);
 926         destroy_workqueue(svc->wq);
 927         kfree(svc->input_phys);
 928         kfree(svc);
 929 }
 930
 931 struct device_type greybus_svc_type = {
 932         .name           = "greybus_svc",
 933         .release        = gb_svc_release,
 934 };
 935
 936 struct gb_svc *gb_svc_create(struct gb_host_device *hd)
 937 {
 938         struct gb_svc *svc;
 939
 940         svc = kzalloc(sizeof(*svc), GFP_KERNEL);
 941         if (!svc)
 942                 return NULL;
 943
 944         svc->wq = alloc_workqueue("%s:svc", WQ_UNBOUND, 1, dev_name(&hd->dev));
 945         if (!svc->wq) {
 946                 kfree(svc);
 947                 return NULL;
 948         }
 949
 950         svc->dev.parent = &hd->dev;
 951         svc->dev.bus = &greybus_bus_type;
 952         svc->dev.type = &greybus_svc_type;
 953         svc->dev.groups = svc_groups;
 954         svc->dev.dma_mask = svc->dev.parent->dma_mask;
 955         device_initialize(&svc->dev);
 956
 957         dev_set_name(&svc->dev, "%d-svc", hd->bus_id);
 958
 959         ida_init(&svc->device_id_map);
 960         svc->state = GB_SVC_STATE_RESET;
 961         svc->hd = hd;
 962
 963         svc->input = gb_svc_input_create(svc);
 964         if (IS_ERR(svc->input)) {
 965                 dev_err(&svc->dev, "failed to create input device: %ld\n",
 966                         PTR_ERR(svc->input));
 967                 goto err_put_device;
 968         }
 969
 970         svc->connection = gb_connection_create_static(hd, GB_SVC_CPORT_ID,
 971                                                 gb_svc_request_handler);
 972         if (IS_ERR(svc->connection)) {
 973                 dev_err(&svc->dev, "failed to create connection: %ld\n",
 974                                 PTR_ERR(svc->connection));
 975                 goto err_free_input;
 976         }
 977
 978         gb_connection_set_data(svc->connection, svc);
 979
 980         return svc;
 981
 982 err_free_input:
 983         input_free_device(svc->input);
 984 err_put_device:
 985         put_device(&svc->dev);
 986         return NULL;
 987 }
 988
 989 int gb_svc_add(struct gb_svc *svc)
 990 {
 991         int ret;
 992
 993         /*
 994          * The SVC protocol is currently driven by the SVC, so the SVC device
 995          * is added from the connection request handler when enough
 996          * information has been received.
 997          */
 998         ret = gb_connection_enable(svc->connection);
 999         if (ret)
1000                 return ret;
1001
1002         return 0;
1003 }
1004
1005 static void gb_svc_remove_interfaces(struct gb_svc *svc)
1006 {
1007         struct gb_interface *intf, *tmp;
1008
1009         list_for_each_entry_safe(intf, tmp, &svc->hd->interfaces, links) {
1010                 gb_interface_disable(intf);
1011                 gb_interface_remove(intf);
1012         }
1013 }
1014
1015 void gb_svc_del(struct gb_svc *svc)
1016 {
1017         gb_connection_disable(svc->connection);
1018
1019         /*
1020          * The SVC device and input device may have been registered
1021          * from the request handler.
1022          */
1023         if (device_is_registered(&svc->dev)) {
1024                 gb_svc_watchdog_destroy(svc);
1025                 input_unregister_device(svc->input);
1026                 device_del(&svc->dev);
1027         }
1028
1029         flush_workqueue(svc->wq);
1030
1031         gb_svc_remove_interfaces(svc);
1032 }
1033
1034 void gb_svc_put(struct gb_svc *svc)
1035 {
1036         put_device(&svc->dev);
1037 }