drivers/hid/hid-hyperv.c

   1 /*
   2  *  Copyright (c) 2009, Citrix Systems, Inc.
   3  *  Copyright (c) 2010, Microsoft Corporation.
   4  *  Copyright (c) 2011, Novell Inc.
   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 #include <linux/init.h>
  16 #include <linux/module.h>
  17 #include <linux/device.h>
  18 #include <linux/completion.h>
  19 #include <linux/input.h>
  20 #include <linux/hid.h>
  21 #include <linux/hiddev.h>
  22 #include <linux/hyperv.h>
  23
  24
  25 struct hv_input_dev_info {
  26         unsigned int size;
  27         unsigned short vendor;
  28         unsigned short product;
  29         unsigned short version;
  30         unsigned short reserved[11];
  31 };
  32
  33 /* The maximum size of a synthetic input message. */
  34 #define SYNTHHID_MAX_INPUT_REPORT_SIZE 16
  35
  36 /*
  37  * Current version
  38  *
  39  * History:
  40  * Beta, RC < 2008/1/22        1,0
  41  * RC > 2008/1/22              2,0
  42  */
  43 #define SYNTHHID_INPUT_VERSION_MAJOR    2
  44 #define SYNTHHID_INPUT_VERSION_MINOR    0
  45 #define SYNTHHID_INPUT_VERSION          (SYNTHHID_INPUT_VERSION_MINOR | \
  46                                          (SYNTHHID_INPUT_VERSION_MAJOR << 16))
  47
  48
  49 #pragma pack(push, 1)
  50 /*
  51  * Message types in the synthetic input protocol
  52  */
  53 enum synthhid_msg_type {
  54         SYNTH_HID_PROTOCOL_REQUEST,
  55         SYNTH_HID_PROTOCOL_RESPONSE,
  56         SYNTH_HID_INITIAL_DEVICE_INFO,
  57         SYNTH_HID_INITIAL_DEVICE_INFO_ACK,
  58         SYNTH_HID_INPUT_REPORT,
  59         SYNTH_HID_MAX
  60 };
  61
  62 /*
  63  * Basic message structures.
  64  */
  65 struct synthhid_msg_hdr {
  66         enum synthhid_msg_type type;
  67         u32 size;
  68 };
  69
  70 struct synthhid_msg {
  71         struct synthhid_msg_hdr header;
  72         char data[1]; /* Enclosed message */
  73 };
  74
  75 union synthhid_version {
  76         struct {
  77                 u16 minor_version;
  78                 u16 major_version;
  79         };
  80         u32 version;
  81 };
  82
  83 /*
  84  * Protocol messages
  85  */
  86 struct synthhid_protocol_request {
  87         struct synthhid_msg_hdr header;
  88         union synthhid_version version_requested;
  89 };
  90
  91 struct synthhid_protocol_response {
  92         struct synthhid_msg_hdr header;
  93         union synthhid_version version_requested;
  94         unsigned char approved;
  95 };
  96
  97 struct synthhid_device_info {
  98         struct synthhid_msg_hdr header;
  99         struct hv_input_dev_info hid_dev_info;
 100         struct hid_descriptor hid_descriptor;
 101 };
 102
 103 struct synthhid_device_info_ack {
 104         struct synthhid_msg_hdr header;
 105         unsigned char reserved;
 106 };
 107
 108 struct synthhid_input_report {
 109         struct synthhid_msg_hdr header;
 110         char buffer[1];
 111 };
 112
 113 #pragma pack(pop)
 114
 115 #define INPUTVSC_SEND_RING_BUFFER_SIZE          (10*PAGE_SIZE)
 116 #define INPUTVSC_RECV_RING_BUFFER_SIZE          (10*PAGE_SIZE)
 117
 118
 119 enum pipe_prot_msg_type {
 120         PIPE_MESSAGE_INVALID,
 121         PIPE_MESSAGE_DATA,
 122         PIPE_MESSAGE_MAXIMUM
 123 };
 124
 125
 126 struct pipe_prt_msg {
 127         enum pipe_prot_msg_type type;
 128         u32 size;
 129         char data[1];
 130 };
 131
 132 struct  mousevsc_prt_msg {
 133         enum pipe_prot_msg_type type;
 134         u32 size;
 135         union {
 136                 struct synthhid_protocol_request request;
 137                 struct synthhid_protocol_response response;
 138                 struct synthhid_device_info_ack ack;
 139         };
 140 };
 141
 142 /*
 143  * Represents an mousevsc device
 144  */
 145 struct mousevsc_dev {
 146         struct hv_device        *device;
 147         bool                    init_complete;
 148         bool                    connected;
 149         struct mousevsc_prt_msg protocol_req;
 150         struct mousevsc_prt_msg protocol_resp;
 151         /* Synchronize the request/response if needed */
 152         struct completion       wait_event;
 153         int                     dev_info_status;
 154
 155         struct hid_descriptor   *hid_desc;
 156         unsigned char           *report_desc;
 157         u32                     report_desc_size;
 158         struct hv_input_dev_info hid_dev_info;
 159         struct hid_device       *hid_device;
 160 };
 161
 162
 163 static struct mousevsc_dev *mousevsc_alloc_device(struct hv_device *device)
 164 {
 165         struct mousevsc_dev *input_dev;
 166
 167         input_dev = kzalloc(sizeof(struct mousevsc_dev), GFP_KERNEL);
 168
 169         if (!input_dev)
 170                 return NULL;
 171
 172         input_dev->device = device;
 173         hv_set_drvdata(device, input_dev);
 174         init_completion(&input_dev->wait_event);
 175         input_dev->init_complete = false;
 176
 177         return input_dev;
 178 }
 179
 180 static void mousevsc_free_device(struct mousevsc_dev *device)
 181 {
 182         kfree(device->hid_desc);
 183         kfree(device->report_desc);
 184         hv_set_drvdata(device->device, NULL);
 185         kfree(device);
 186 }
 187
 188 static void mousevsc_on_receive_device_info(struct mousevsc_dev *input_device,
 189                                 struct synthhid_device_info *device_info)
 190 {
 191         int ret = 0;
 192         struct hid_descriptor *desc;
 193         struct mousevsc_prt_msg ack;
 194
 195         input_device->dev_info_status = -ENOMEM;
 196
 197         input_device->hid_dev_info = device_info->hid_dev_info;
 198         desc = &device_info->hid_descriptor;
 199         if (desc->bLength == 0)
 200                 goto cleanup;
 201
 202         input_device->hid_desc = kmemdup(desc, desc->bLength, GFP_ATOMIC);
 203
 204         if (!input_device->hid_desc)
 205                 goto cleanup;
 206
 207         input_device->report_desc_size = desc->desc[0].wDescriptorLength;
 208         if (input_device->report_desc_size == 0) {
 209                 input_device->dev_info_status = -EINVAL;
 210                 goto cleanup;
 211         }
 212
 213         input_device->report_desc = kzalloc(input_device->report_desc_size,
 214                                           GFP_ATOMIC);
 215
 216         if (!input_device->report_desc) {
 217                 input_device->dev_info_status = -ENOMEM;
 218                 goto cleanup;
 219         }
 220
 221         memcpy(input_device->report_desc,
 222                ((unsigned char *)desc) + desc->bLength,
 223                desc->desc[0].wDescriptorLength);
 224
 225         /* Send the ack */
 226         memset(&ack, 0, sizeof(struct mousevsc_prt_msg));
 227
 228         ack.type = PIPE_MESSAGE_DATA;
 229         ack.size = sizeof(struct synthhid_device_info_ack);
 230
 231         ack.ack.header.type = SYNTH_HID_INITIAL_DEVICE_INFO_ACK;
 232         ack.ack.header.size = 1;
 233         ack.ack.reserved = 0;
 234
 235         ret = vmbus_sendpacket(input_device->device->channel,
 236                         &ack,
 237                         sizeof(struct pipe_prt_msg) - sizeof(unsigned char) +
 238                         sizeof(struct synthhid_device_info_ack),
 239                         (unsigned long)&ack,
 240                         VM_PKT_DATA_INBAND,
 241                         VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
 242
 243         if (!ret)
 244                 input_device->dev_info_status = 0;
 245
 246 cleanup:
 247         complete(&input_device->wait_event);
 248
 249         return;
 250 }
 251
 252 static void mousevsc_on_receive(struct hv_device *device,
 253                                 struct vmpacket_descriptor *packet)
 254 {
 255         struct pipe_prt_msg *pipe_msg;
 256         struct synthhid_msg *hid_msg;
 257         struct mousevsc_dev *input_dev = hv_get_drvdata(device);
 258         struct synthhid_input_report *input_report;
 259
 260         pipe_msg = (struct pipe_prt_msg *)((unsigned long)packet +
 261                                                 (packet->offset8 << 3));
 262
 263         if (pipe_msg->type != PIPE_MESSAGE_DATA)
 264                 return;
 265
 266         hid_msg = (struct synthhid_msg *)pipe_msg->data;
 267
 268         switch (hid_msg->header.type) {
 269         case SYNTH_HID_PROTOCOL_RESPONSE:
 270                 /*
 271                  * While it will be impossible for us to protect against
 272                  * malicious/buggy hypervisor/host, add a check here to
 273                  * ensure we don't corrupt memory.
 274                  */
 275                 if ((pipe_msg->size + sizeof(struct pipe_prt_msg)
 276                         - sizeof(unsigned char))
 277                         > sizeof(struct mousevsc_prt_msg)) {
 278                         WARN_ON(1);
 279                         break;
 280                 }
 281
 282                 memcpy(&input_dev->protocol_resp, pipe_msg,
 283                        pipe_msg->size + sizeof(struct pipe_prt_msg) -
 284                        sizeof(unsigned char));
 285                 complete(&input_dev->wait_event);
 286                 break;
 287
 288         case SYNTH_HID_INITIAL_DEVICE_INFO:
 289                 WARN_ON(pipe_msg->size < sizeof(struct hv_input_dev_info));
 290
 291                 /*
 292                  * Parse out the device info into device attr,
 293                  * hid desc and report desc
 294                  */
 295                 mousevsc_on_receive_device_info(input_dev,
 296                         (struct synthhid_device_info *)pipe_msg->data);
 297                 break;
 298         case SYNTH_HID_INPUT_REPORT:
 299                 input_report =
 300                         (struct synthhid_input_report *)pipe_msg->data;
 301                 if (!input_dev->init_complete)
 302                         break;
 303                 hid_input_report(input_dev->hid_device,
 304                                 HID_INPUT_REPORT, input_report->buffer,
 305                                 input_report->header.size, 1);
 306                 break;
 307         default:
 308                 pr_err("unsupported hid msg type - type %d len %d",
 309                        hid_msg->header.type, hid_msg->header.size);
 310                 break;
 311         }
 312
 313 }
 314
 315 static void mousevsc_on_channel_callback(void *context)
 316 {
 317         const int packet_size = 0x100;
 318         int ret;
 319         struct hv_device *device = context;
 320         u32 bytes_recvd;
 321         u64 req_id;
 322         struct vmpacket_descriptor *desc;
 323         unsigned char   *buffer;
 324         int     bufferlen = packet_size;
 325
 326         buffer = kmalloc(bufferlen, GFP_ATOMIC);
 327         if (!buffer)
 328                 return;
 329
 330         do {
 331                 ret = vmbus_recvpacket_raw(device->channel, buffer,
 332                                         bufferlen, &bytes_recvd, &req_id);
 333
 334                 switch (ret) {
 335                 case 0:
 336                         if (bytes_recvd <= 0) {
 337                                 kfree(buffer);
 338                                 return;
 339                         }
 340                         desc = (struct vmpacket_descriptor *)buffer;
 341
 342                         switch (desc->type) {
 343                         case VM_PKT_COMP:
 344                                 break;
 345
 346                         case VM_PKT_DATA_INBAND:
 347                                 mousevsc_on_receive(device, desc);
 348                                 break;
 349
 350                         default:
 351                                 pr_err("unhandled packet type %d, tid %llx len %d\n",
 352                                         desc->type, req_id, bytes_recvd);
 353                                 break;
 354                         }
 355
 356                         break;
 357
 358                 case -ENOBUFS:
 359                         kfree(buffer);
 360                         /* Handle large packet */
 361                         bufferlen = bytes_recvd;
 362                         buffer = kmalloc(bytes_recvd, GFP_ATOMIC);
 363
 364                         if (!buffer)
 365                                 return;
 366
 367                         break;
 368                 }
 369         } while (1);
 370
 371 }
 372
 373 static int mousevsc_connect_to_vsp(struct hv_device *device)
 374 {
 375         int ret = 0;
 376         int t;
 377         struct mousevsc_dev *input_dev = hv_get_drvdata(device);
 378         struct mousevsc_prt_msg *request;
 379         struct mousevsc_prt_msg *response;
 380
 381         request = &input_dev->protocol_req;
 382         memset(request, 0, sizeof(struct mousevsc_prt_msg));
 383
 384         request->type = PIPE_MESSAGE_DATA;
 385         request->size = sizeof(struct synthhid_protocol_request);
 386         request->request.header.type = SYNTH_HID_PROTOCOL_REQUEST;
 387         request->request.header.size = sizeof(unsigned int);
 388         request->request.version_requested.version = SYNTHHID_INPUT_VERSION;
 389
 390         ret = vmbus_sendpacket(device->channel, request,
 391                                 sizeof(struct pipe_prt_msg) -
 392                                 sizeof(unsigned char) +
 393                                 sizeof(struct synthhid_protocol_request),
 394                                 (unsigned long)request,
 395                                 VM_PKT_DATA_INBAND,
 396                                 VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
 397         if (ret)
 398                 goto cleanup;
 399
 400         t = wait_for_completion_timeout(&input_dev->wait_event, 5*HZ);
 401         if (!t) {
 402                 ret = -ETIMEDOUT;
 403                 goto cleanup;
 404         }
 405
 406         response = &input_dev->protocol_resp;
 407
 408         if (!response->response.approved) {
 409                 pr_err("synthhid protocol request failed (version %d)\n",
 410                        SYNTHHID_INPUT_VERSION);
 411                 ret = -ENODEV;
 412                 goto cleanup;
 413         }
 414
 415         t = wait_for_completion_timeout(&input_dev->wait_event, 5*HZ);
 416         if (!t) {
 417                 ret = -ETIMEDOUT;
 418                 goto cleanup;
 419         }
 420
 421         /*
 422          * We should have gotten the device attr, hid desc and report
 423          * desc at this point
 424          */
 425         ret = input_dev->dev_info_status;
 426
 427 cleanup:
 428         return ret;
 429 }
 430
 431 static int mousevsc_hid_parse(struct hid_device *hid)
 432 {
 433         struct hv_device *dev = hid_get_drvdata(hid);
 434         struct mousevsc_dev *input_dev = hv_get_drvdata(dev);
 435
 436         return hid_parse_report(hid, input_dev->report_desc,
 437                                 input_dev->report_desc_size);
 438 }
 439
 440 static int mousevsc_hid_open(struct hid_device *hid)
 441 {
 442         return 0;
 443 }
 444
 445 static int mousevsc_hid_start(struct hid_device *hid)
 446 {
 447         return 0;
 448 }
 449
 450 static void mousevsc_hid_close(struct hid_device *hid)
 451 {
 452 }
 453
 454 static void mousevsc_hid_stop(struct hid_device *hid)
 455 {
 456 }
 457
 458 static struct hid_ll_driver mousevsc_ll_driver = {
 459         .parse = mousevsc_hid_parse,
 460         .open = mousevsc_hid_open,
 461         .close = mousevsc_hid_close,
 462         .start = mousevsc_hid_start,
 463         .stop = mousevsc_hid_stop,
 464 };
 465
 466 static struct hid_driver mousevsc_hid_driver;
 467
 468 static int mousevsc_probe(struct hv_device *device,
 469                         const struct hv_vmbus_device_id *dev_id)
 470 {
 471         int ret;
 472         struct mousevsc_dev *input_dev;
 473         struct hid_device *hid_dev;
 474
 475         input_dev = mousevsc_alloc_device(device);
 476
 477         if (!input_dev)
 478                 return -ENOMEM;
 479
 480         ret = vmbus_open(device->channel,
 481                 INPUTVSC_SEND_RING_BUFFER_SIZE,
 482                 INPUTVSC_RECV_RING_BUFFER_SIZE,
 483                 NULL,
 484                 0,
 485                 mousevsc_on_channel_callback,
 486                 device
 487                 );
 488
 489         if (ret)
 490                 goto probe_err0;
 491
 492         ret = mousevsc_connect_to_vsp(device);
 493
 494         if (ret)
 495                 goto probe_err1;
 496
 497         /* workaround SA-167 */
 498         if (input_dev->report_desc[14] == 0x25)
 499                 input_dev->report_desc[14] = 0x29;
 500
 501         hid_dev = hid_allocate_device();
 502         if (IS_ERR(hid_dev)) {
 503                 ret = PTR_ERR(hid_dev);
 504                 goto probe_err1;
 505         }
 506
 507         hid_dev->ll_driver = &mousevsc_ll_driver;
 508         hid_dev->driver = &mousevsc_hid_driver;
 509         hid_dev->bus = BUS_VIRTUAL;
 510         hid_dev->vendor = input_dev->hid_dev_info.vendor;
 511         hid_dev->product = input_dev->hid_dev_info.product;
 512         hid_dev->version = input_dev->hid_dev_info.version;
 513         input_dev->hid_device = hid_dev;
 514
 515         sprintf(hid_dev->name, "%s", "Microsoft Vmbus HID-compliant Mouse");
 516
 517         hid_set_drvdata(hid_dev, device);
 518
 519         ret = hid_add_device(hid_dev);
 520         if (ret)
 521                 goto probe_err1;
 522
 523
 524         ret = hid_parse(hid_dev);
 525         if (ret) {
 526                 hid_err(hid_dev, "parse failed\n");
 527                 goto probe_err2;
 528         }
 529
 530         ret = hid_hw_start(hid_dev, HID_CONNECT_HIDINPUT | HID_CONNECT_HIDDEV);
 531
 532         if (ret) {
 533                 hid_err(hid_dev, "hw start failed\n");
 534                 goto probe_err2;
 535         }
 536
 537         input_dev->connected = true;
 538         input_dev->init_complete = true;
 539
 540         return ret;
 541
 542 probe_err2:
 543         hid_destroy_device(hid_dev);
 544
 545 probe_err1:
 546         vmbus_close(device->channel);
 547
 548 probe_err0:
 549         mousevsc_free_device(input_dev);
 550
 551         return ret;
 552 }
 553
 554
 555 static int mousevsc_remove(struct hv_device *dev)
 556 {
 557         struct mousevsc_dev *input_dev = hv_get_drvdata(dev);
 558
 559         vmbus_close(dev->channel);
 560         hid_hw_stop(input_dev->hid_device);
 561         hid_destroy_device(input_dev->hid_device);
 562         mousevsc_free_device(input_dev);
 563
 564         return 0;
 565 }
 566
 567 static const struct hv_vmbus_device_id id_table[] = {
 568         /* Mouse guid */
 569         { HV_MOUSE_GUID, },
 570         { },
 571 };
 572
 573 MODULE_DEVICE_TABLE(vmbus, id_table);
 574
 575 static struct  hv_driver mousevsc_drv = {
 576         .name = KBUILD_MODNAME,
 577         .id_table = id_table,
 578         .probe = mousevsc_probe,
 579         .remove = mousevsc_remove,
 580 };
 581
 582 static int __init mousevsc_init(void)
 583 {
 584         return vmbus_driver_register(&mousevsc_drv);
 585 }
 586
 587 static void __exit mousevsc_exit(void)
 588 {
 589         vmbus_driver_unregister(&mousevsc_drv);
 590 }
 591
 592 MODULE_LICENSE("GPL");
 593 module_init(mousevsc_init);
 594 module_exit(mousevsc_exit);