drivers/misc/mei/hbm.c

   1 /*
   2  *
   3  * Intel Management Engine Interface (Intel MEI) Linux driver
   4  * Copyright (c) 2003-2012, Intel Corporation.
   5  *
   6  * This program is free software; you can redistribute it and/or modify it
   7  * under the terms and conditions of the GNU General Public License,
   8  * version 2, as published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope it will be useful, but WITHOUT
  11  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  12  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  13  * more details.
  14  *
  15  */
  16
  17 #include <linux/export.h>
  18 #include <linux/pci.h>
  19 #include <linux/sched.h>
  20 #include <linux/wait.h>
  21 #include <linux/mei.h>
  22 #include <linux/pm_runtime.h>
  23
  24 #include "mei_dev.h"
  25 #include "hbm.h"
  26 #include "client.h"
  27
  28 static const char *mei_cl_conn_status_str(enum mei_cl_connect_status status)
  29 {
  30 #define MEI_CL_CS(status) case MEI_CL_CONN_##status: return #status
  31         switch (status) {
  32         MEI_CL_CS(SUCCESS);
  33         MEI_CL_CS(NOT_FOUND);
  34         MEI_CL_CS(ALREADY_STARTED);
  35         MEI_CL_CS(OUT_OF_RESOURCES);
  36         MEI_CL_CS(MESSAGE_SMALL);
  37         default: return "unknown";
  38         }
  39 #undef MEI_CL_CCS
  40 }
  41
  42 /**
  43  * mei_cl_conn_status_to_errno - convert client connect response
  44  * status to error code
  45  *
  46  * @status: client connect response status
  47  *
  48  * returns corresponding error code
  49  */
  50 static int mei_cl_conn_status_to_errno(enum mei_cl_connect_status status)
  51 {
  52         switch (status) {
  53         case MEI_CL_CONN_SUCCESS:          return 0;
  54         case MEI_CL_CONN_NOT_FOUND:        return -ENOTTY;
  55         case MEI_CL_CONN_ALREADY_STARTED:  return -EBUSY;
  56         case MEI_CL_CONN_OUT_OF_RESOURCES: return -EBUSY;
  57         case MEI_CL_CONN_MESSAGE_SMALL:    return -EINVAL;
  58         default:                           return -EINVAL;
  59         }
  60 }
  61
  62 /**
  63  * mei_hbm_idle - set hbm to idle state
  64  *
  65  * @dev: the device structure
  66  */
  67 void mei_hbm_idle(struct mei_device *dev)
  68 {
  69         dev->init_clients_timer = 0;
  70         dev->hbm_state = MEI_HBM_IDLE;
  71 }
  72
  73 /**
  74  * mei_me_cl_remove_all - remove all me clients
  75  *
  76  * @dev: the device structure
  77  */
  78 static void mei_me_cl_remove_all(struct mei_device *dev)
  79 {
  80         struct mei_me_client *me_cl, *next;
  81         list_for_each_entry_safe(me_cl, next, &dev->me_clients, list) {
  82                         list_del(&me_cl->list);
  83                         kfree(me_cl);
  84         }
  85 }
  86
  87 /**
  88  * mei_hbm_reset - reset hbm counters and book keeping data structurs
  89  *
  90  * @dev: the device structure
  91  */
  92 void mei_hbm_reset(struct mei_device *dev)
  93 {
  94         dev->me_client_presentation_num = 0;
  95         dev->me_client_index = 0;
  96
  97         mei_me_cl_remove_all(dev);
  98
  99         mei_hbm_idle(dev);
 100 }
 101
 102 /**
 103  * mei_hbm_cl_hdr - construct client hbm header
 104  *
 105  * @cl: client
 106  * @hbm_cmd: host bus message command
 107  * @buf: buffer for cl header
 108  * @len: buffer length
 109  */
 110 static inline
 111 void mei_hbm_cl_hdr(struct mei_cl *cl, u8 hbm_cmd, void *buf, size_t len)
 112 {
 113         struct mei_hbm_cl_cmd *cmd = buf;
 114
 115         memset(cmd, 0, len);
 116
 117         cmd->hbm_cmd = hbm_cmd;
 118         cmd->host_addr = cl->host_client_id;
 119         cmd->me_addr = cl->me_client_id;
 120 }
 121
 122 /**
 123  * mei_hbm_cl_write - write simple hbm client message
 124  *
 125  * @dev: the device structure
 126  * @cl: client
 127  * @hbm_cmd: host bus message command
 128  * @len: buffer length
 129  */
 130 static inline
 131 int mei_hbm_cl_write(struct mei_device *dev,
 132                      struct mei_cl *cl, u8 hbm_cmd, size_t len)
 133 {
 134         struct mei_msg_hdr *mei_hdr = &dev->wr_msg.hdr;
 135
 136         mei_hbm_hdr(mei_hdr, len);
 137         mei_hbm_cl_hdr(cl, hbm_cmd, dev->wr_msg.data, len);
 138
 139         return mei_write_message(dev, mei_hdr, dev->wr_msg.data);
 140 }
 141
 142 /**
 143  * mei_hbm_cl_addr_equal - tells if they have the same address
 144  *
 145  * @cl: - client
 146  * @buf: buffer with cl header
 147  *
 148  * returns true if addresses are the same
 149  */
 150 static inline
 151 bool mei_hbm_cl_addr_equal(struct mei_cl *cl, void *buf)
 152 {
 153         struct mei_hbm_cl_cmd *cmd = buf;
 154         return cl->host_client_id == cmd->host_addr &&
 155                 cl->me_client_id == cmd->me_addr;
 156 }
 157
 158
 159 int mei_hbm_start_wait(struct mei_device *dev)
 160 {
 161         int ret;
 162         if (dev->hbm_state > MEI_HBM_START)
 163                 return 0;
 164
 165         mutex_unlock(&dev->device_lock);
 166         ret = wait_event_interruptible_timeout(dev->wait_recvd_msg,
 167                         dev->hbm_state == MEI_HBM_IDLE ||
 168                         dev->hbm_state >= MEI_HBM_STARTED,
 169                         mei_secs_to_jiffies(MEI_HBM_TIMEOUT));
 170         mutex_lock(&dev->device_lock);
 171
 172         if (ret <= 0 && (dev->hbm_state <= MEI_HBM_START)) {
 173                 dev->hbm_state = MEI_HBM_IDLE;
 174                 dev_err(&dev->pdev->dev, "waiting for mei start failed\n");
 175                 return -ETIME;
 176         }
 177         return 0;
 178 }
 179
 180 /**
 181  * mei_hbm_start_req - sends start request message.
 182  *
 183  * @dev: the device structure
 184  *
 185  * returns 0 on success and < 0 on failure
 186  */
 187 int mei_hbm_start_req(struct mei_device *dev)
 188 {
 189         struct mei_msg_hdr *mei_hdr = &dev->wr_msg.hdr;
 190         struct hbm_host_version_request *start_req;
 191         const size_t len = sizeof(struct hbm_host_version_request);
 192         int ret;
 193
 194         mei_hbm_reset(dev);
 195
 196         mei_hbm_hdr(mei_hdr, len);
 197
 198         /* host start message */
 199         start_req = (struct hbm_host_version_request *)dev->wr_msg.data;
 200         memset(start_req, 0, len);
 201         start_req->hbm_cmd = HOST_START_REQ_CMD;
 202         start_req->host_version.major_version = HBM_MAJOR_VERSION;
 203         start_req->host_version.minor_version = HBM_MINOR_VERSION;
 204
 205         dev->hbm_state = MEI_HBM_IDLE;
 206         ret = mei_write_message(dev, mei_hdr, dev->wr_msg.data);
 207         if (ret) {
 208                 dev_err(&dev->pdev->dev, "version message write failed: ret = %d\n",
 209                         ret);
 210                 return ret;
 211         }
 212
 213         dev->hbm_state = MEI_HBM_START;
 214         dev->init_clients_timer = MEI_CLIENTS_INIT_TIMEOUT;
 215         return 0;
 216 }
 217
 218 /*
 219  * mei_hbm_enum_clients_req - sends enumeration client request message.
 220  *
 221  * @dev: the device structure
 222  *
 223  * returns 0 on success and < 0 on failure
 224  */
 225 static int mei_hbm_enum_clients_req(struct mei_device *dev)
 226 {
 227         struct mei_msg_hdr *mei_hdr = &dev->wr_msg.hdr;
 228         struct hbm_host_enum_request *enum_req;
 229         const size_t len = sizeof(struct hbm_host_enum_request);
 230         int ret;
 231
 232         /* enumerate clients */
 233         mei_hbm_hdr(mei_hdr, len);
 234
 235         enum_req = (struct hbm_host_enum_request *)dev->wr_msg.data;
 236         memset(enum_req, 0, len);
 237         enum_req->hbm_cmd = HOST_ENUM_REQ_CMD;
 238
 239         ret = mei_write_message(dev, mei_hdr, dev->wr_msg.data);
 240         if (ret) {
 241                 dev_err(&dev->pdev->dev, "enumeration request write failed: ret = %d.\n",
 242                         ret);
 243                 return ret;
 244         }
 245         dev->hbm_state = MEI_HBM_ENUM_CLIENTS;
 246         dev->init_clients_timer = MEI_CLIENTS_INIT_TIMEOUT;
 247         return 0;
 248 }
 249
 250 /*
 251  * mei_hbm_me_cl_add - add new me client to the list
 252  *
 253  * @dev: the device structure
 254  * @res: hbm property response
 255  *
 256  * returns 0 on success and -ENOMEM on allocation failure
 257  */
 258
 259 static int mei_hbm_me_cl_add(struct mei_device *dev,
 260                              struct hbm_props_response *res)
 261 {
 262         struct mei_me_client *me_cl;
 263
 264         me_cl = kzalloc(sizeof(struct mei_me_client), GFP_KERNEL);
 265         if (!me_cl)
 266                 return -ENOMEM;
 267
 268         me_cl->props = res->client_properties;
 269         me_cl->client_id = res->me_addr;
 270         me_cl->mei_flow_ctrl_creds = 0;
 271
 272         list_add(&me_cl->list, &dev->me_clients);
 273         return 0;
 274 }
 275
 276 /**
 277  * mei_hbm_prop_req - request property for a single client
 278  *
 279  * @dev: the device structure
 280  *
 281  * returns 0 on success and < 0 on failure
 282  */
 283
 284 static int mei_hbm_prop_req(struct mei_device *dev)
 285 {
 286
 287         struct mei_msg_hdr *mei_hdr = &dev->wr_msg.hdr;
 288         struct hbm_props_request *prop_req;
 289         const size_t len = sizeof(struct hbm_props_request);
 290         unsigned long next_client_index;
 291         int ret;
 292
 293         next_client_index = find_next_bit(dev->me_clients_map, MEI_CLIENTS_MAX,
 294                                           dev->me_client_index);
 295
 296         /* We got all client properties */
 297         if (next_client_index == MEI_CLIENTS_MAX) {
 298                 dev->hbm_state = MEI_HBM_STARTED;
 299                 schedule_work(&dev->init_work);
 300
 301                 return 0;
 302         }
 303
 304         mei_hbm_hdr(mei_hdr, len);
 305         prop_req = (struct hbm_props_request *)dev->wr_msg.data;
 306
 307         memset(prop_req, 0, sizeof(struct hbm_props_request));
 308
 309         prop_req->hbm_cmd = HOST_CLIENT_PROPERTIES_REQ_CMD;
 310         prop_req->me_addr = next_client_index;
 311
 312         ret = mei_write_message(dev, mei_hdr, dev->wr_msg.data);
 313         if (ret) {
 314                 dev_err(&dev->pdev->dev, "properties request write failed: ret = %d\n",
 315                         ret);
 316                 return ret;
 317         }
 318
 319         dev->init_clients_timer = MEI_CLIENTS_INIT_TIMEOUT;
 320         dev->me_client_index = next_client_index;
 321
 322         return 0;
 323 }
 324
 325 /*
 326  * mei_hbm_pg - sends pg command
 327  *
 328  * @dev: the device structure
 329  * @pg_cmd: the pg command code
 330  *
 331  * This function returns -EIO on write failure
 332  */
 333 int mei_hbm_pg(struct mei_device *dev, u8 pg_cmd)
 334 {
 335         struct mei_msg_hdr *mei_hdr = &dev->wr_msg.hdr;
 336         struct hbm_power_gate *req;
 337         const size_t len = sizeof(struct hbm_power_gate);
 338         int ret;
 339
 340         mei_hbm_hdr(mei_hdr, len);
 341
 342         req = (struct hbm_power_gate *)dev->wr_msg.data;
 343         memset(req, 0, len);
 344         req->hbm_cmd = pg_cmd;
 345
 346         ret = mei_write_message(dev, mei_hdr, dev->wr_msg.data);
 347         if (ret)
 348                 dev_err(&dev->pdev->dev, "power gate command write failed.\n");
 349         return ret;
 350 }
 351 EXPORT_SYMBOL_GPL(mei_hbm_pg);
 352
 353 /**
 354  * mei_hbm_stop_req - send stop request message
 355  *
 356  * @dev - mei device
 357  * @cl: client info
 358  *
 359  * This function returns -EIO on write failure
 360  */
 361 static int mei_hbm_stop_req(struct mei_device *dev)
 362 {
 363         struct mei_msg_hdr *mei_hdr = &dev->wr_msg.hdr;
 364         struct hbm_host_stop_request *req =
 365                         (struct hbm_host_stop_request *)dev->wr_msg.data;
 366         const size_t len = sizeof(struct hbm_host_stop_request);
 367
 368         mei_hbm_hdr(mei_hdr, len);
 369
 370         memset(req, 0, len);
 371         req->hbm_cmd = HOST_STOP_REQ_CMD;
 372         req->reason = DRIVER_STOP_REQUEST;
 373
 374         return mei_write_message(dev, mei_hdr, dev->wr_msg.data);
 375 }
 376
 377 /**
 378  * mei_hbm_cl_flow_control_req - sends flow control request.
 379  *
 380  * @dev: the device structure
 381  * @cl: client info
 382  *
 383  * This function returns -EIO on write failure
 384  */
 385 int mei_hbm_cl_flow_control_req(struct mei_device *dev, struct mei_cl *cl)
 386 {
 387         const size_t len = sizeof(struct hbm_flow_control);
 388         cl_dbg(dev, cl, "sending flow control\n");
 389         return mei_hbm_cl_write(dev, cl, MEI_FLOW_CONTROL_CMD, len);
 390 }
 391
 392 /**
 393  * mei_hbm_add_single_flow_creds - adds single buffer credentials.
 394  *
 395  * @dev: the device structure
 396  * @flow: flow control.
 397  *
 398  * return 0 on success, < 0 otherwise
 399  */
 400 static int mei_hbm_add_single_flow_creds(struct mei_device *dev,
 401                                   struct hbm_flow_control *flow)
 402 {
 403         struct mei_me_client *me_cl;
 404
 405         me_cl = mei_me_cl_by_id(dev, flow->me_addr);
 406         if (!me_cl) {
 407                 dev_err(&dev->pdev->dev, "no such me client %d\n",
 408                         flow->me_addr);
 409                 return -ENOENT;
 410         }
 411
 412         if (WARN_ON(me_cl->props.single_recv_buf == 0))
 413                 return -EINVAL;
 414
 415         me_cl->mei_flow_ctrl_creds++;
 416         dev_dbg(&dev->pdev->dev, "recv flow ctrl msg ME %d (single) creds = %d.\n",
 417             flow->me_addr, me_cl->mei_flow_ctrl_creds);
 418
 419         return 0;
 420 }
 421
 422 /**
 423  * mei_hbm_cl_flow_control_res - flow control response from me
 424  *
 425  * @dev: the device structure
 426  * @flow_control: flow control response bus message
 427  */
 428 static void mei_hbm_cl_flow_control_res(struct mei_device *dev,
 429                 struct hbm_flow_control *flow_control)
 430 {
 431         struct mei_cl *cl;
 432
 433         if (!flow_control->host_addr) {
 434                 /* single receive buffer */
 435                 mei_hbm_add_single_flow_creds(dev, flow_control);
 436                 return;
 437         }
 438
 439         /* normal connection */
 440         list_for_each_entry(cl, &dev->file_list, link) {
 441                 if (mei_hbm_cl_addr_equal(cl, flow_control)) {
 442                         cl->mei_flow_ctrl_creds++;
 443                         dev_dbg(&dev->pdev->dev, "flow ctrl msg for host %d ME %d creds %d.\n",
 444                                 flow_control->host_addr, flow_control->me_addr,
 445                                 cl->mei_flow_ctrl_creds);
 446                         break;
 447                 }
 448         }
 449 }
 450
 451
 452 /**
 453  * mei_hbm_cl_disconnect_req - sends disconnect message to fw.
 454  *
 455  * @dev: the device structure
 456  * @cl: a client to disconnect from
 457  *
 458  * This function returns -EIO on write failure
 459  */
 460 int mei_hbm_cl_disconnect_req(struct mei_device *dev, struct mei_cl *cl)
 461 {
 462         const size_t len = sizeof(struct hbm_client_connect_request);
 463         return mei_hbm_cl_write(dev, cl, CLIENT_DISCONNECT_REQ_CMD, len);
 464 }
 465
 466 /**
 467  * mei_hbm_cl_disconnect_rsp - sends disconnect respose to the FW
 468  *
 469  * @dev: the device structure
 470  * @cl: a client to disconnect from
 471  *
 472  * This function returns -EIO on write failure
 473  */
 474 int mei_hbm_cl_disconnect_rsp(struct mei_device *dev, struct mei_cl *cl)
 475 {
 476         const size_t len = sizeof(struct hbm_client_connect_response);
 477         return mei_hbm_cl_write(dev, cl, CLIENT_DISCONNECT_RES_CMD, len);
 478 }
 479
 480 /**
 481  * mei_hbm_cl_disconnect_res - disconnect response from ME
 482  *
 483  * @dev: the device structure
 484  * @rs: disconnect response bus message
 485  */
 486 static void mei_hbm_cl_disconnect_res(struct mei_device *dev,
 487                 struct hbm_client_connect_response *rs)
 488 {
 489         struct mei_cl *cl;
 490         struct mei_cl_cb *cb, *next;
 491
 492         dev_dbg(&dev->pdev->dev, "hbm: disconnect response cl:host=%02d me=%02d status=%d\n",
 493                         rs->me_addr, rs->host_addr, rs->status);
 494
 495         list_for_each_entry_safe(cb, next, &dev->ctrl_rd_list.list, list) {
 496                 cl = cb->cl;
 497
 498                 /* this should not happen */
 499                 if (WARN_ON(!cl)) {
 500                         list_del(&cb->list);
 501                         return;
 502                 }
 503
 504                 if (mei_hbm_cl_addr_equal(cl, rs)) {
 505                         list_del(&cb->list);
 506                         if (rs->status == MEI_CL_DISCONN_SUCCESS)
 507                                 cl->state = MEI_FILE_DISCONNECTED;
 508
 509                         cl->status = 0;
 510                         cl->timer_count = 0;
 511                         break;
 512                 }
 513         }
 514 }
 515
 516 /**
 517  * mei_hbm_cl_connect_req - send connection request to specific me client
 518  *
 519  * @dev: the device structure
 520  * @cl: a client to connect to
 521  *
 522  * returns -EIO on write failure
 523  */
 524 int mei_hbm_cl_connect_req(struct mei_device *dev, struct mei_cl *cl)
 525 {
 526         const size_t len = sizeof(struct hbm_client_connect_request);
 527         return mei_hbm_cl_write(dev, cl, CLIENT_CONNECT_REQ_CMD, len);
 528 }
 529
 530 /**
 531  * mei_hbm_cl_connect_res - connect response from the ME
 532  *
 533  * @dev: the device structure
 534  * @rs: connect response bus message
 535  */
 536 static void mei_hbm_cl_connect_res(struct mei_device *dev,
 537                 struct hbm_client_connect_response *rs)
 538 {
 539
 540         struct mei_cl *cl;
 541         struct mei_cl_cb *cb, *next;
 542
 543         dev_dbg(&dev->pdev->dev, "hbm: connect response cl:host=%02d me=%02d status=%s\n",
 544                         rs->me_addr, rs->host_addr,
 545                         mei_cl_conn_status_str(rs->status));
 546
 547         cl = NULL;
 548
 549         list_for_each_entry_safe(cb, next, &dev->ctrl_rd_list.list, list) {
 550
 551                 cl = cb->cl;
 552                 /* this should not happen */
 553                 if (WARN_ON(!cl)) {
 554                         list_del_init(&cb->list);
 555                         continue;
 556                 }
 557
 558                 if (cb->fop_type !=  MEI_FOP_CONNECT)
 559                         continue;
 560
 561                 if (mei_hbm_cl_addr_equal(cl, rs)) {
 562                         list_del(&cb->list);
 563                         break;
 564                 }
 565         }
 566
 567         if (!cl)
 568                 return;
 569
 570         cl->timer_count = 0;
 571         if (rs->status == MEI_CL_CONN_SUCCESS)
 572                 cl->state = MEI_FILE_CONNECTED;
 573         else
 574                 cl->state = MEI_FILE_DISCONNECTED;
 575         cl->status = mei_cl_conn_status_to_errno(rs->status);
 576 }
 577
 578
 579 /**
 580  * mei_hbm_fw_disconnect_req - disconnect request initiated by ME firmware
 581  *  host sends disconnect response
 582  *
 583  * @dev: the device structure.
 584  * @disconnect_req: disconnect request bus message from the me
 585  *
 586  * returns -ENOMEM on allocation failure
 587  */
 588 static int mei_hbm_fw_disconnect_req(struct mei_device *dev,
 589                 struct hbm_client_connect_request *disconnect_req)
 590 {
 591         struct mei_cl *cl;
 592         struct mei_cl_cb *cb;
 593
 594         list_for_each_entry(cl, &dev->file_list, link) {
 595                 if (mei_hbm_cl_addr_equal(cl, disconnect_req)) {
 596                         dev_dbg(&dev->pdev->dev, "disconnect request host client %d ME client %d.\n",
 597                                         disconnect_req->host_addr,
 598                                         disconnect_req->me_addr);
 599                         cl->state = MEI_FILE_DISCONNECTED;
 600                         cl->timer_count = 0;
 601
 602                         cb = mei_io_cb_init(cl, NULL);
 603                         if (!cb)
 604                                 return -ENOMEM;
 605                         cb->fop_type = MEI_FOP_DISCONNECT_RSP;
 606                         cl_dbg(dev, cl, "add disconnect response as first\n");
 607                         list_add(&cb->list, &dev->ctrl_wr_list.list);
 608
 609                         break;
 610                 }
 611         }
 612         return 0;
 613 }
 614
 615
 616 /**
 617  * mei_hbm_version_is_supported - checks whether the driver can
 618  *     support the hbm version of the device
 619  *
 620  * @dev: the device structure
 621  * returns true if driver can support hbm version of the device
 622  */
 623 bool mei_hbm_version_is_supported(struct mei_device *dev)
 624 {
 625         return  (dev->version.major_version < HBM_MAJOR_VERSION) ||
 626                 (dev->version.major_version == HBM_MAJOR_VERSION &&
 627                  dev->version.minor_version <= HBM_MINOR_VERSION);
 628 }
 629
 630 /**
 631  * mei_hbm_dispatch - bottom half read routine after ISR to
 632  * handle the read bus message cmd processing.
 633  *
 634  * @dev: the device structure
 635  * @mei_hdr: header of bus message
 636  *
 637  * returns 0 on success and < 0 on failure
 638  */
 639 int mei_hbm_dispatch(struct mei_device *dev, struct mei_msg_hdr *hdr)
 640 {
 641         struct mei_bus_message *mei_msg;
 642         struct hbm_host_version_response *version_res;
 643         struct hbm_client_connect_response *connect_res;
 644         struct hbm_client_connect_response *disconnect_res;
 645         struct hbm_client_connect_request *disconnect_req;
 646         struct hbm_flow_control *flow_control;
 647         struct hbm_props_response *props_res;
 648         struct hbm_host_enum_response *enum_res;
 649
 650         /* read the message to our buffer */
 651         BUG_ON(hdr->length >= sizeof(dev->rd_msg_buf));
 652         mei_read_slots(dev, dev->rd_msg_buf, hdr->length);
 653         mei_msg = (struct mei_bus_message *)dev->rd_msg_buf;
 654
 655         /* ignore spurious message and prevent reset nesting
 656          * hbm is put to idle during system reset
 657          */
 658         if (dev->hbm_state == MEI_HBM_IDLE) {
 659                 dev_dbg(&dev->pdev->dev, "hbm: state is idle ignore spurious messages\n");
 660                 return 0;
 661         }
 662
 663         switch (mei_msg->hbm_cmd) {
 664         case HOST_START_RES_CMD:
 665                 dev_dbg(&dev->pdev->dev, "hbm: start: response message received.\n");
 666
 667                 dev->init_clients_timer = 0;
 668
 669                 version_res = (struct hbm_host_version_response *)mei_msg;
 670
 671                 dev_dbg(&dev->pdev->dev, "HBM VERSION: DRIVER=%02d:%02d DEVICE=%02d:%02d\n",
 672                                 HBM_MAJOR_VERSION, HBM_MINOR_VERSION,
 673                                 version_res->me_max_version.major_version,
 674                                 version_res->me_max_version.minor_version);
 675
 676                 if (version_res->host_version_supported) {
 677                         dev->version.major_version = HBM_MAJOR_VERSION;
 678                         dev->version.minor_version = HBM_MINOR_VERSION;
 679                 } else {
 680                         dev->version.major_version =
 681                                 version_res->me_max_version.major_version;
 682                         dev->version.minor_version =
 683                                 version_res->me_max_version.minor_version;
 684                 }
 685
 686                 if (!mei_hbm_version_is_supported(dev)) {
 687                         dev_warn(&dev->pdev->dev, "hbm: start: version mismatch - stopping the driver.\n");
 688
 689                         dev->hbm_state = MEI_HBM_STOPPED;
 690                         if (mei_hbm_stop_req(dev)) {
 691                                 dev_err(&dev->pdev->dev, "hbm: start: failed to send stop request\n");
 692                                 return -EIO;
 693                         }
 694                         break;
 695                 }
 696
 697                 if (dev->dev_state != MEI_DEV_INIT_CLIENTS ||
 698                     dev->hbm_state != MEI_HBM_START) {
 699                         dev_err(&dev->pdev->dev, "hbm: start: state mismatch, [%d, %d]\n",
 700                                 dev->dev_state, dev->hbm_state);
 701                         return -EPROTO;
 702                 }
 703
 704                 dev->hbm_state = MEI_HBM_STARTED;
 705
 706                 if (mei_hbm_enum_clients_req(dev)) {
 707                         dev_err(&dev->pdev->dev, "hbm: start: failed to send enumeration request\n");
 708                         return -EIO;
 709                 }
 710
 711                 wake_up_interruptible(&dev->wait_recvd_msg);
 712                 break;
 713
 714         case CLIENT_CONNECT_RES_CMD:
 715                 dev_dbg(&dev->pdev->dev, "hbm: client connect response: message received.\n");
 716
 717                 connect_res = (struct hbm_client_connect_response *) mei_msg;
 718                 mei_hbm_cl_connect_res(dev, connect_res);
 719                 wake_up(&dev->wait_recvd_msg);
 720                 break;
 721
 722         case CLIENT_DISCONNECT_RES_CMD:
 723                 dev_dbg(&dev->pdev->dev, "hbm: client disconnect response: message received.\n");
 724
 725                 disconnect_res = (struct hbm_client_connect_response *) mei_msg;
 726                 mei_hbm_cl_disconnect_res(dev, disconnect_res);
 727                 wake_up(&dev->wait_recvd_msg);
 728                 break;
 729
 730         case MEI_FLOW_CONTROL_CMD:
 731                 dev_dbg(&dev->pdev->dev, "hbm: client flow control response: message received.\n");
 732
 733                 flow_control = (struct hbm_flow_control *) mei_msg;
 734                 mei_hbm_cl_flow_control_res(dev, flow_control);
 735                 break;
 736
 737         case MEI_PG_ISOLATION_ENTRY_RES_CMD:
 738                 dev_dbg(&dev->pdev->dev, "power gate isolation entry response received\n");
 739                 dev->pg_event = MEI_PG_EVENT_RECEIVED;
 740                 if (waitqueue_active(&dev->wait_pg))
 741                         wake_up(&dev->wait_pg);
 742                 break;
 743
 744         case MEI_PG_ISOLATION_EXIT_REQ_CMD:
 745                 dev_dbg(&dev->pdev->dev, "power gate isolation exit request received\n");
 746                 dev->pg_event = MEI_PG_EVENT_RECEIVED;
 747                 if (waitqueue_active(&dev->wait_pg))
 748                         wake_up(&dev->wait_pg);
 749                 else
 750                         /*
 751                         * If the driver is not waiting on this then
 752                         * this is HW initiated exit from PG.
 753                         * Start runtime pm resume sequence to exit from PG.
 754                         */
 755                         pm_request_resume(&dev->pdev->dev);
 756                 break;
 757
 758         case HOST_CLIENT_PROPERTIES_RES_CMD:
 759                 dev_dbg(&dev->pdev->dev, "hbm: properties response: message received.\n");
 760
 761                 dev->init_clients_timer = 0;
 762
 763                 if (dev->dev_state != MEI_DEV_INIT_CLIENTS ||
 764                     dev->hbm_state != MEI_HBM_CLIENT_PROPERTIES) {
 765                         dev_err(&dev->pdev->dev, "hbm: properties response: state mismatch, [%d, %d]\n",
 766                                 dev->dev_state, dev->hbm_state);
 767                         return -EPROTO;
 768                 }
 769
 770                 props_res = (struct hbm_props_response *)mei_msg;
 771
 772                 if (props_res->status) {
 773                         dev_err(&dev->pdev->dev, "hbm: properties response: wrong status = %d\n",
 774                                 props_res->status);
 775                         return -EPROTO;
 776                 }
 777
 778                 mei_hbm_me_cl_add(dev, props_res);
 779
 780                 dev->me_client_index++;
 781                 dev->me_client_presentation_num++;
 782
 783                 /* request property for the next client */
 784                 if (mei_hbm_prop_req(dev))
 785                         return -EIO;
 786
 787                 break;
 788
 789         case HOST_ENUM_RES_CMD:
 790                 dev_dbg(&dev->pdev->dev, "hbm: enumeration response: message received\n");
 791
 792                 dev->init_clients_timer = 0;
 793
 794                 enum_res = (struct hbm_host_enum_response *) mei_msg;
 795                 BUILD_BUG_ON(sizeof(dev->me_clients_map)
 796                                 < sizeof(enum_res->valid_addresses));
 797                 memcpy(dev->me_clients_map, enum_res->valid_addresses,
 798                                 sizeof(enum_res->valid_addresses));
 799
 800                 if (dev->dev_state != MEI_DEV_INIT_CLIENTS ||
 801                     dev->hbm_state != MEI_HBM_ENUM_CLIENTS) {
 802                         dev_err(&dev->pdev->dev, "hbm: enumeration response: state mismatch, [%d, %d]\n",
 803                                 dev->dev_state, dev->hbm_state);
 804                         return -EPROTO;
 805                 }
 806
 807                 dev->hbm_state = MEI_HBM_CLIENT_PROPERTIES;
 808
 809                 /* first property request */
 810                 if (mei_hbm_prop_req(dev))
 811                         return -EIO;
 812
 813                 break;
 814
 815         case HOST_STOP_RES_CMD:
 816                 dev_dbg(&dev->pdev->dev, "hbm: stop response: message received\n");
 817
 818                 dev->init_clients_timer = 0;
 819
 820                 if (dev->hbm_state != MEI_HBM_STOPPED) {
 821                         dev_err(&dev->pdev->dev, "hbm: stop response: state mismatch, [%d, %d]\n",
 822                                 dev->dev_state, dev->hbm_state);
 823                         return -EPROTO;
 824                 }
 825
 826                 dev->dev_state = MEI_DEV_POWER_DOWN;
 827                 dev_info(&dev->pdev->dev, "hbm: stop response: resetting.\n");
 828                 /* force the reset */
 829                 return -EPROTO;
 830                 break;
 831
 832         case CLIENT_DISCONNECT_REQ_CMD:
 833                 dev_dbg(&dev->pdev->dev, "hbm: disconnect request: message received\n");
 834
 835                 disconnect_req = (struct hbm_client_connect_request *)mei_msg;
 836                 mei_hbm_fw_disconnect_req(dev, disconnect_req);
 837                 break;
 838
 839         case ME_STOP_REQ_CMD:
 840                 dev_dbg(&dev->pdev->dev, "hbm: stop request: message received\n");
 841                 dev->hbm_state = MEI_HBM_STOPPED;
 842                 if (mei_hbm_stop_req(dev)) {
 843                         dev_err(&dev->pdev->dev, "hbm: start: failed to send stop request\n");
 844                         return -EIO;
 845                 }
 846                 break;
 847         default:
 848                 BUG();
 849                 break;
 850
 851         }
 852         return 0;
 853 }
 854