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 "greybus.h"
  11
  12 struct gb_svc {
  13         struct gb_connection    *connection;
  14         u8                      version_major;
  15         u8                      version_minor;
  16 };
  17
  18 static struct ida greybus_svc_device_id_map;
  19
  20 /*
  21  * AP's SVC cport is required early to get messages from the SVC. This happens
  22  * even before the Endo is created and hence any modules or interfaces.
  23  *
  24  * This is a temporary connection, used only at initial bootup.
  25  */
  26 struct gb_connection *
  27 gb_ap_svc_connection_create(struct greybus_host_device *hd)
  28 {
  29         struct gb_connection *connection;
  30
  31         connection = gb_connection_create_range(hd, NULL, hd->parent,
  32                                                 GB_SVC_CPORT_ID,
  33                                                 GREYBUS_PROTOCOL_SVC,
  34                                                 GB_SVC_CPORT_ID,
  35                                                 GB_SVC_CPORT_ID + 1);
  36
  37         return connection;
  38 }
  39 EXPORT_SYMBOL_GPL(gb_ap_svc_connection_create);
  40
  41 /*
  42  * We know endo-type and AP's interface id now, lets create a proper svc
  43  * connection (and its interface/bundle) now and get rid of the initial
  44  * 'partially' initialized one svc connection.
  45  */
  46 static struct gb_interface *
  47 gb_ap_interface_create(struct greybus_host_device *hd,
  48                        struct gb_connection *connection, u8 interface_id)
  49 {
  50         struct gb_interface *intf;
  51         struct device *dev = &hd->endo->dev;
  52
  53         intf = gb_interface_create(hd, interface_id);
  54         if (!intf) {
  55                 dev_err(dev, "%s: Failed to create interface with id %hhu\n",
  56                         __func__, interface_id);
  57                 return NULL;
  58         }
  59
  60         intf->device_id = GB_DEVICE_ID_AP;
  61         svc_update_connection(intf, connection);
  62
  63         /* Its no longer a partially initialized connection */
  64         hd->initial_svc_connection = NULL;
  65
  66         return intf;
  67 }
  68
  69 static int intf_device_id_operation(struct gb_svc *svc,
  70                                 u8 intf_id, u8 device_id)
  71 {
  72         struct gb_svc_intf_device_id_request request;
  73
  74         request.intf_id = intf_id;
  75         request.device_id = device_id;
  76
  77         return gb_operation_sync(svc->connection, GB_SVC_TYPE_INTF_DEVICE_ID,
  78                                  &request, sizeof(request), NULL, 0);
  79 }
  80
  81 static int intf_reset_operation(struct gb_svc *svc, u8 intf_id)
  82 {
  83         struct gb_svc_intf_reset_request request;
  84
  85         request.intf_id = intf_id;
  86
  87         return gb_operation_sync(svc->connection, GB_SVC_TYPE_INTF_RESET,
  88                                  &request, sizeof(request), NULL, 0);
  89 }
  90
  91 static int connection_create_operation(struct gb_svc *svc,
  92                                 u8 intf1_id, u16 cport1_id,
  93                                 u8 intf2_id, u16 cport2_id)
  94 {
  95         struct gb_svc_conn_create_request request;
  96
  97         request.intf1_id = intf1_id;
  98         request.cport1_id = cport1_id;
  99         request.intf2_id = intf2_id;
 100         request.cport2_id = cport2_id;
 101
 102         return gb_operation_sync(svc->connection, GB_SVC_TYPE_CONN_CREATE,
 103                                  &request, sizeof(request), NULL, 0);
 104 }
 105
 106 static int connection_destroy_operation(struct gb_svc *svc,
 107                                 u8 intf1_id, u16 cport1_id,
 108                                 u8 intf2_id, u16 cport2_id)
 109 {
 110         struct gb_svc_conn_destroy_request request;
 111
 112         request.intf1_id = intf1_id;
 113         request.cport1_id = cport1_id;
 114         request.intf2_id = intf2_id;
 115         request.cport2_id = cport2_id;
 116
 117         return gb_operation_sync(svc->connection, GB_SVC_TYPE_CONN_DESTROY,
 118                                  &request, sizeof(request), NULL, 0);
 119 }
 120
 121 int gb_svc_intf_device_id(struct gb_svc *svc, u8 intf_id, u8 device_id)
 122 {
 123         return intf_device_id_operation(svc, intf_id, device_id);
 124 }
 125 EXPORT_SYMBOL_GPL(gb_svc_intf_device_id);
 126
 127 int gb_svc_intf_reset(struct gb_svc *svc, u8 intf_id)
 128 {
 129         return intf_reset_operation(svc, intf_id);
 130 }
 131 EXPORT_SYMBOL_GPL(gb_svc_intf_reset);
 132
 133 int gb_svc_connection_create(struct gb_svc *svc,
 134                                 u8 intf1_id, u16 cport1_id,
 135                                 u8 intf2_id, u16 cport2_id)
 136 {
 137         return connection_create_operation(svc, intf1_id, cport1_id,
 138                                                 intf2_id, cport2_id);
 139 }
 140 EXPORT_SYMBOL_GPL(gb_svc_connection_create);
 141
 142 int gb_svc_connection_destroy(struct gb_svc *svc,
 143                                 u8 intf1_id, u16 cport1_id,
 144                                 u8 intf2_id, u16 cport2_id)
 145 {
 146         return connection_destroy_operation(svc, intf1_id, cport1_id,
 147                                                 intf2_id, cport2_id);
 148 }
 149 EXPORT_SYMBOL_GPL(gb_svc_connection_destroy);
 150
 151 static int gb_svc_version_request(struct gb_operation *op)
 152 {
 153         struct gb_connection *connection = op->connection;
 154         struct gb_protocol_version_response *version;
 155         struct device *dev = &connection->dev;
 156
 157         version = op->request->payload;
 158
 159         if (version->major > GB_SVC_VERSION_MAJOR) {
 160                 dev_err(&connection->dev,
 161                         "unsupported major version (%hhu > %hhu)\n",
 162                         version->major, GB_SVC_VERSION_MAJOR);
 163                 return -ENOTSUPP;
 164         }
 165
 166         if (!gb_operation_response_alloc(op, sizeof(*version), GFP_KERNEL)) {
 167                 dev_err(dev, "%s: error allocating response\n",
 168                                 __func__);
 169                 return -ENOMEM;
 170         }
 171
 172         version = op->response->payload;
 173         version->major = GB_SVC_VERSION_MAJOR;
 174         version->minor = GB_SVC_VERSION_MINOR;
 175         return 0;
 176 }
 177
 178 static int gb_svc_hello(struct gb_operation *op)
 179 {
 180         struct gb_connection *connection = op->connection;
 181         struct greybus_host_device *hd = connection->hd;
 182         struct gb_svc_hello_request *hello_request;
 183         struct device *dev = &connection->dev;
 184         struct gb_interface *intf;
 185         u16 endo_id;
 186         u8 interface_id;
 187         int ret;
 188
 189         /* Hello message should be received only during early bootup */
 190         WARN_ON(hd->initial_svc_connection != connection);
 191
 192         /*
 193          * SVC sends information about the endo and interface-id on the hello
 194          * request, use that to create an endo.
 195          */
 196         if (op->request->payload_size != sizeof(*hello_request)) {
 197                 dev_err(dev, "%s: Illegal size of hello request (%zu %zu)\n",
 198                         __func__, op->request->payload_size,
 199                         sizeof(*hello_request));
 200                 return -EINVAL;
 201         }
 202
 203         hello_request = op->request->payload;
 204         endo_id = le16_to_cpu(hello_request->endo_id);
 205         interface_id = hello_request->interface_id;
 206
 207         /* Setup Endo */
 208         ret = greybus_endo_setup(hd, endo_id, interface_id);
 209         if (ret)
 210                 return ret;
 211
 212         /*
 213          * Endo and its modules are ready now, fix AP's partially initialized
 214          * svc protocol and its connection.
 215          */
 216         intf = gb_ap_interface_create(hd, connection, interface_id);
 217         if (!intf) {
 218                 gb_endo_remove(hd->endo);
 219                 return ret;
 220         }
 221
 222         return 0;
 223 }
 224
 225 static int gb_svc_intf_hotplug_recv(struct gb_operation *op)
 226 {
 227         struct gb_message *request = op->request;
 228         struct gb_svc_intf_hotplug_request *hotplug = request->payload;
 229         struct gb_svc *svc = op->connection->private;
 230         struct greybus_host_device *hd = op->connection->bundle->intf->hd;
 231         struct device *dev = &op->connection->dev;
 232         struct gb_interface *intf;
 233         u8 intf_id, device_id;
 234         u32 unipro_mfg_id;
 235         u32 unipro_prod_id;
 236         u32 ara_vend_id;
 237         u32 ara_prod_id;
 238         int ret;
 239
 240         if (request->payload_size < sizeof(*hotplug)) {
 241                 dev_err(dev, "%s: short hotplug request received\n", __func__);
 242                 return -EINVAL;
 243         }
 244
 245         /*
 246          * Grab the information we need.
 247          *
 248          * XXX I'd really like to acknowledge receipt, and then
 249          * XXX continue processing the request.  There's no need
 250          * XXX for the SVC to wait.  In fact, it might be best to
 251          * XXX have the SVC get acknowledgement before we proceed.
 252          */
 253         intf_id = hotplug->intf_id;
 254         unipro_mfg_id = le32_to_cpu(hotplug->data.unipro_mfg_id);
 255         unipro_prod_id = le32_to_cpu(hotplug->data.unipro_prod_id);
 256         ara_vend_id = le32_to_cpu(hotplug->data.ara_vend_id);
 257         ara_prod_id = le32_to_cpu(hotplug->data.ara_prod_id);
 258
 259         // FIXME May require firmware download
 260         intf = gb_interface_create(hd, intf_id);
 261         if (!intf) {
 262                 dev_err(dev, "%s: Failed to create interface with id %hhu\n",
 263                         __func__, intf_id);
 264                 return -EINVAL;
 265         }
 266
 267         /*
 268          * Create a device id for the interface:
 269          * - device id 0 (GB_DEVICE_ID_SVC) belongs to the SVC
 270          * - device id 1 (GB_DEVICE_ID_AP) belongs to the AP
 271          *
 272          * XXX Do we need to allocate device ID for SVC or the AP here? And what
 273          * XXX about an AP with multiple interface blocks?
 274          */
 275         device_id = ida_simple_get(&greybus_svc_device_id_map,
 276                                    GB_DEVICE_ID_MODULES_START, 0, GFP_ATOMIC);
 277         if (device_id < 0) {
 278                 ret = device_id;
 279                 dev_err(dev, "%s: Failed to allocate device id for interface with id %hhu (%d)\n",
 280                         __func__, intf_id, ret);
 281                 goto destroy_interface;
 282         }
 283
 284         ret = intf_device_id_operation(svc, intf_id, device_id);
 285         if (ret) {
 286                 dev_err(dev, "%s: Device id operation failed, interface %hhu device_id %hhu (%d)\n",
 287                         __func__, intf_id, device_id, ret);
 288                 goto ida_put;
 289         }
 290
 291         ret = gb_interface_init(intf, device_id);
 292         if (ret) {
 293                 dev_err(dev, "%s: Failed to initialize interface, interface %hhu device_id %hhu (%d)\n",
 294                         __func__, intf_id, device_id, ret);
 295                 goto svc_id_free;
 296         }
 297
 298         return 0;
 299
 300 svc_id_free:
 301         /*
 302          * XXX Should we tell SVC that this id doesn't belong to interface
 303          * XXX anymore.
 304          */
 305 ida_put:
 306         ida_simple_remove(&greybus_svc_device_id_map, device_id);
 307 destroy_interface:
 308         gb_interface_remove(hd, intf_id);
 309
 310         return ret;
 311 }
 312
 313 static int gb_svc_intf_hot_unplug_recv(struct gb_operation *op)
 314 {
 315         struct gb_message *request = op->request;
 316         struct gb_svc_intf_hot_unplug_request *hot_unplug = request->payload;
 317         struct greybus_host_device *hd = op->connection->bundle->intf->hd;
 318         struct device *dev = &op->connection->dev;
 319         u8 device_id;
 320         struct gb_interface *intf;
 321         u8 intf_id;
 322
 323         if (request->payload_size < sizeof(*hot_unplug)) {
 324                 dev_err(&op->connection->dev,
 325                         "short hot unplug request received\n");
 326                 return -EINVAL;
 327         }
 328
 329         intf_id = hot_unplug->intf_id;
 330
 331         intf = gb_interface_find(hd, intf_id);
 332         if (!intf) {
 333                 dev_err(dev, "%s: Couldn't find interface for id %hhu\n",
 334                         __func__, intf_id);
 335                 return -EINVAL;
 336         }
 337
 338         device_id = intf->device_id;
 339         gb_interface_remove(hd, intf_id);
 340         ida_simple_remove(&greybus_svc_device_id_map, device_id);
 341
 342         return 0;
 343 }
 344
 345 static int gb_svc_intf_reset_recv(struct gb_operation *op)
 346 {
 347         struct gb_message *request = op->request;
 348         struct gb_svc_intf_reset_request *reset;
 349         u8 intf_id;
 350
 351         if (request->payload_size < sizeof(*reset)) {
 352                 dev_err(&op->connection->dev,
 353                         "short reset request received\n");
 354                 return -EINVAL;
 355         }
 356         reset = request->payload;
 357
 358         intf_id = reset->intf_id;
 359
 360         /* FIXME Reset the interface here */
 361
 362         return 0;
 363 }
 364
 365 static int gb_svc_request_recv(u8 type, struct gb_operation *op)
 366 {
 367         switch (type) {
 368         case GB_SVC_TYPE_PROTOCOL_VERSION:
 369                 return gb_svc_version_request(op);
 370         case GB_SVC_TYPE_SVC_HELLO:
 371                 return gb_svc_hello(op);
 372         case GB_SVC_TYPE_INTF_HOTPLUG:
 373                 return gb_svc_intf_hotplug_recv(op);
 374         case GB_SVC_TYPE_INTF_HOT_UNPLUG:
 375                 return gb_svc_intf_hot_unplug_recv(op);
 376         case GB_SVC_TYPE_INTF_RESET:
 377                 return gb_svc_intf_reset_recv(op);
 378         default:
 379                 dev_err(&op->connection->dev,
 380                         "unsupported request: %hhu\n", type);
 381                 return -EINVAL;
 382         }
 383 }
 384
 385 static int gb_svc_connection_init(struct gb_connection *connection)
 386 {
 387         struct gb_svc *svc;
 388
 389         svc = kzalloc(sizeof(*svc), GFP_KERNEL);
 390         if (!svc)
 391                 return -ENOMEM;
 392
 393         svc->connection = connection;
 394         connection->private = svc;
 395
 396         WARN_ON(connection->hd->initial_svc_connection);
 397         connection->hd->initial_svc_connection = connection;
 398
 399         ida_init(&greybus_svc_device_id_map);
 400
 401         return 0;
 402 }
 403
 404 static void gb_svc_connection_exit(struct gb_connection *connection)
 405 {
 406         struct gb_svc *svc = connection->private;
 407
 408         connection->private = NULL;
 409         kfree(svc);
 410 }
 411
 412 static struct gb_protocol svc_protocol = {
 413         .name                   = "svc",
 414         .id                     = GREYBUS_PROTOCOL_SVC,
 415         .major                  = GB_SVC_VERSION_MAJOR,
 416         .minor                  = GB_SVC_VERSION_MINOR,
 417         .connection_init        = gb_svc_connection_init,
 418         .connection_exit        = gb_svc_connection_exit,
 419         .request_recv           = gb_svc_request_recv,
 420 };
 421 gb_builtin_protocol_driver(svc_protocol);