drivers/hid/hid-hyperv.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  *  Copyright (c) 2009, Citrix Systems, Inc.
   4  *  Copyright (c) 2010, Microsoft Corporation.
   5  *  Copyright (c) 2011, Novell Inc.
   6  */
   7 #include <linux/init.h>
   8 #include <linux/module.h>
   9 #include <linux/device.h>
  10 #include <linux/completion.h>
  11 #include <linux/input.h>
  12 #include <linux/hid.h>
  13 #include <linux/hiddev.h>
  14 #include <linux/hyperv.h>
  15
  16
  17 struct hv_input_dev_info {
  18         unsigned int size;
  19         unsigned short vendor;
  20         unsigned short product;
  21         unsigned short version;
  22         unsigned short reserved[11];
  23 };
  24
  25 /*
  26  * Current version
  27  *
  28  * History:
  29  * Beta, RC < 2008/1/22        1,0
  30  * RC > 2008/1/22              2,0
  31  */
  32 #define SYNTHHID_INPUT_VERSION_MAJOR    2
  33 #define SYNTHHID_INPUT_VERSION_MINOR    0
  34 #define SYNTHHID_INPUT_VERSION          (SYNTHHID_INPUT_VERSION_MINOR | \
  35                                          (SYNTHHID_INPUT_VERSION_MAJOR << 16))
  36
  37
  38 #pragma pack(push, 1)
  39 /*
  40  * Message types in the synthetic input protocol
  41  */
  42 enum synthhid_msg_type {
  43         SYNTH_HID_PROTOCOL_REQUEST,
  44         SYNTH_HID_PROTOCOL_RESPONSE,
  45         SYNTH_HID_INITIAL_DEVICE_INFO,
  46         SYNTH_HID_INITIAL_DEVICE_INFO_ACK,
  47         SYNTH_HID_INPUT_REPORT,
  48         SYNTH_HID_MAX
  49 };
  50
  51 /*
  52  * Basic message structures.
  53  */
  54 struct synthhid_msg_hdr {
  55         enum synthhid_msg_type type;
  56         u32 size;
  57 };
  58
  59 union synthhid_version {
  60         struct {
  61                 u16 minor_version;
  62                 u16 major_version;
  63         };
  64         u32 version;
  65 };
  66
  67 /*
  68  * Protocol messages
  69  */
  70 struct synthhid_protocol_request {
  71         struct synthhid_msg_hdr header;
  72         union synthhid_version version_requested;
  73 };
  74
  75 struct synthhid_protocol_response {
  76         struct synthhid_msg_hdr header;
  77         union synthhid_version version_requested;
  78         unsigned char approved;
  79 };
  80
  81 struct synthhid_device_info {
  82         struct synthhid_msg_hdr header;
  83         struct hv_input_dev_info hid_dev_info;
  84         struct hid_descriptor hid_descriptor;
  85 };
  86
  87 struct synthhid_device_info_ack {
  88         struct synthhid_msg_hdr header;
  89         unsigned char reserved;
  90 };
  91
  92 struct synthhid_input_report {
  93         struct synthhid_msg_hdr header;
  94         char buffer[];
  95 };
  96
  97 #pragma pack(pop)
  98
  99 #define INPUTVSC_SEND_RING_BUFFER_SIZE  VMBUS_RING_SIZE(36 * 1024)
 100 #define INPUTVSC_RECV_RING_BUFFER_SIZE  VMBUS_RING_SIZE(36 * 1024)
 101
 102
 103 enum pipe_prot_msg_type {
 104         PIPE_MESSAGE_INVALID,
 105         PIPE_MESSAGE_DATA,
 106         PIPE_MESSAGE_MAXIMUM
 107 };
 108
 109
 110 struct pipe_prt_msg {
 111         enum pipe_prot_msg_type type;
 112         u32 size;
 113         char data[];
 114 };
 115
 116 struct  mousevsc_prt_msg {
 117         enum pipe_prot_msg_type type;
 118         u32 size;
 119         union {
 120                 struct synthhid_protocol_request request;
 121                 struct synthhid_protocol_response response;
 122                 struct synthhid_device_info_ack ack;
 123         };
 124 };
 125
 126 /*
 127  * Represents an mousevsc device
 128  */
 129 struct mousevsc_dev {
 130         struct hv_device        *device;
 131         bool                    init_complete;
 132         bool                    connected;
 133         struct mousevsc_prt_msg protocol_req;
 134         struct mousevsc_prt_msg protocol_resp;
 135         /* Synchronize the request/response if needed */
 136         struct completion       wait_event;
 137         int                     dev_info_status;
 138
 139         struct hid_descriptor   *hid_desc;
 140         unsigned char           *report_desc;
 141         u32                     report_desc_size;
 142         struct hv_input_dev_info hid_dev_info;
 143         struct hid_device       *hid_device;
 144         u8                      input_buf[HID_MAX_BUFFER_SIZE];
 145 };
 146
 147
 148 static struct mousevsc_dev *mousevsc_alloc_device(struct hv_device *device)
 149 {
 150         struct mousevsc_dev *input_dev;
 151
 152         input_dev = kzalloc(sizeof(struct mousevsc_dev), GFP_KERNEL);
 153
 154         if (!input_dev)
 155                 return NULL;
 156
 157         input_dev->device = device;
 158         hv_set_drvdata(device, input_dev);
 159         init_completion(&input_dev->wait_event);
 160         input_dev->init_complete = false;
 161
 162         return input_dev;
 163 }
 164
 165 static void mousevsc_free_device(struct mousevsc_dev *device)
 166 {
 167         kfree(device->hid_desc);
 168         kfree(device->report_desc);
 169         hv_set_drvdata(device->device, NULL);
 170         kfree(device);
 171 }
 172
 173 static void mousevsc_on_receive_device_info(struct mousevsc_dev *input_device,
 174                                 struct synthhid_device_info *device_info)
 175 {
 176         int ret = 0;
 177         struct hid_descriptor *desc;
 178         struct mousevsc_prt_msg ack;
 179
 180         input_device->dev_info_status = -ENOMEM;
 181
 182         input_device->hid_dev_info = device_info->hid_dev_info;
 183         desc = &device_info->hid_descriptor;
 184         if (desc->bLength == 0)
 185                 goto cleanup;
 186
 187         /* The pointer is not NULL when we resume from hibernation */
 188         kfree(input_device->hid_desc);
 189         input_device->hid_desc = kmemdup(desc, desc->bLength, GFP_ATOMIC);
 190
 191         if (!input_device->hid_desc)
 192                 goto cleanup;
 193
 194         input_device->report_desc_size = le16_to_cpu(
 195                                         desc->desc[0].wDescriptorLength);
 196         if (input_device->report_desc_size == 0) {
 197                 input_device->dev_info_status = -EINVAL;
 198                 goto cleanup;
 199         }
 200
 201         /* The pointer is not NULL when we resume from hibernation */
 202         kfree(input_device->report_desc);
 203         input_device->report_desc = kzalloc(input_device->report_desc_size,
 204                                           GFP_ATOMIC);
 205
 206         if (!input_device->report_desc) {
 207                 input_device->dev_info_status = -ENOMEM;
 208                 goto cleanup;
 209         }
 210
 211         memcpy(input_device->report_desc,
 212                ((unsigned char *)desc) + desc->bLength,
 213                le16_to_cpu(desc->desc[0].wDescriptorLength));
 214
 215         /* Send the ack */
 216         memset(&ack, 0, sizeof(struct mousevsc_prt_msg));
 217
 218         ack.type = PIPE_MESSAGE_DATA;
 219         ack.size = sizeof(struct synthhid_device_info_ack);
 220
 221         ack.ack.header.type = SYNTH_HID_INITIAL_DEVICE_INFO_ACK;
 222         ack.ack.header.size = 1;
 223         ack.ack.reserved = 0;
 224
 225         ret = vmbus_sendpacket(input_device->device->channel,
 226                         &ack,
 227                         sizeof(struct pipe_prt_msg) +
 228                         sizeof(struct synthhid_device_info_ack),
 229                         (unsigned long)&ack,
 230                         VM_PKT_DATA_INBAND,
 231                         VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
 232
 233         if (!ret)
 234                 input_device->dev_info_status = 0;
 235
 236 cleanup:
 237         complete(&input_device->wait_event);
 238
 239         return;
 240 }
 241
 242 static void mousevsc_on_receive(struct hv_device *device,
 243                                 struct vmpacket_descriptor *packet)
 244 {
 245         struct pipe_prt_msg *pipe_msg;
 246         struct synthhid_msg_hdr *hid_msg_hdr;
 247         struct mousevsc_dev *input_dev = hv_get_drvdata(device);
 248         struct synthhid_input_report *input_report;
 249         size_t len;
 250
 251         pipe_msg = (struct pipe_prt_msg *)((unsigned long)packet +
 252                                                 (packet->offset8 << 3));
 253
 254         if (pipe_msg->type != PIPE_MESSAGE_DATA)
 255                 return;
 256
 257         hid_msg_hdr = (struct synthhid_msg_hdr *)pipe_msg->data;
 258
 259         switch (hid_msg_hdr->type) {
 260         case SYNTH_HID_PROTOCOL_RESPONSE:
 261                 len = struct_size(pipe_msg, data, pipe_msg->size);
 262
 263                 /*
 264                  * While it will be impossible for us to protect against
 265                  * malicious/buggy hypervisor/host, add a check here to
 266                  * ensure we don't corrupt memory.
 267                  */
 268                 if (WARN_ON(len > sizeof(struct mousevsc_prt_msg)))
 269                         break;
 270
 271                 memcpy(&input_dev->protocol_resp, pipe_msg, len);
 272                 complete(&input_dev->wait_event);
 273                 break;
 274
 275         case SYNTH_HID_INITIAL_DEVICE_INFO:
 276                 WARN_ON(pipe_msg->size < sizeof(struct hv_input_dev_info));
 277
 278                 /*
 279                  * Parse out the device info into device attr,
 280                  * hid desc and report desc
 281                  */
 282                 mousevsc_on_receive_device_info(input_dev,
 283                         (struct synthhid_device_info *)pipe_msg->data);
 284                 break;
 285         case SYNTH_HID_INPUT_REPORT:
 286                 input_report =
 287                         (struct synthhid_input_report *)pipe_msg->data;
 288                 if (!input_dev->init_complete)
 289                         break;
 290
 291                 len = min(input_report->header.size,
 292                           (u32)sizeof(input_dev->input_buf));
 293                 memcpy(input_dev->input_buf, input_report->buffer, len);
 294                 hid_input_report(input_dev->hid_device, HID_INPUT_REPORT,
 295                                  input_dev->input_buf, len, 1);
 296
 297                 pm_wakeup_hard_event(&input_dev->device->device);
 298
 299                 break;
 300         default:
 301                 pr_err("unsupported hid msg type - type %d len %d\n",
 302                        hid_msg_hdr->type, hid_msg_hdr->size);
 303                 break;
 304         }
 305
 306 }
 307
 308 static void mousevsc_on_channel_callback(void *context)
 309 {
 310         struct hv_device *device = context;
 311         struct vmpacket_descriptor *desc;
 312
 313         foreach_vmbus_pkt(desc, device->channel) {
 314                 switch (desc->type) {
 315                 case VM_PKT_COMP:
 316                         break;
 317
 318                 case VM_PKT_DATA_INBAND:
 319                         mousevsc_on_receive(device, desc);
 320                         break;
 321
 322                 default:
 323                         pr_err("Unhandled packet type %d, tid %llx len %d\n",
 324                                desc->type, desc->trans_id, desc->len8 * 8);
 325                         break;
 326                 }
 327         }
 328 }
 329
 330 static int mousevsc_connect_to_vsp(struct hv_device *device)
 331 {
 332         int ret = 0;
 333         unsigned long t;
 334         struct mousevsc_dev *input_dev = hv_get_drvdata(device);
 335         struct mousevsc_prt_msg *request;
 336         struct mousevsc_prt_msg *response;
 337
 338         reinit_completion(&input_dev->wait_event);
 339
 340         request = &input_dev->protocol_req;
 341         memset(request, 0, sizeof(struct mousevsc_prt_msg));
 342
 343         request->type = PIPE_MESSAGE_DATA;
 344         request->size = sizeof(struct synthhid_protocol_request);
 345         request->request.header.type = SYNTH_HID_PROTOCOL_REQUEST;
 346         request->request.header.size = sizeof(unsigned int);
 347         request->request.version_requested.version = SYNTHHID_INPUT_VERSION;
 348
 349         ret = vmbus_sendpacket(device->channel, request,
 350                                 sizeof(struct pipe_prt_msg) +
 351                                 sizeof(struct synthhid_protocol_request),
 352                                 (unsigned long)request,
 353                                 VM_PKT_DATA_INBAND,
 354                                 VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
 355         if (ret)
 356                 goto cleanup;
 357
 358         t = wait_for_completion_timeout(&input_dev->wait_event, 5*HZ);
 359         if (!t) {
 360                 ret = -ETIMEDOUT;
 361                 goto cleanup;
 362         }
 363
 364         response = &input_dev->protocol_resp;
 365
 366         if (!response->response.approved) {
 367                 pr_err("synthhid protocol request failed (version %d)\n",
 368                        SYNTHHID_INPUT_VERSION);
 369                 ret = -ENODEV;
 370                 goto cleanup;
 371         }
 372
 373         t = wait_for_completion_timeout(&input_dev->wait_event, 5*HZ);
 374         if (!t) {
 375                 ret = -ETIMEDOUT;
 376                 goto cleanup;
 377         }
 378
 379         /*
 380          * We should have gotten the device attr, hid desc and report
 381          * desc at this point
 382          */
 383         ret = input_dev->dev_info_status;
 384
 385 cleanup:
 386         return ret;
 387 }
 388
 389 static int mousevsc_hid_parse(struct hid_device *hid)
 390 {
 391         struct hv_device *dev = hid_get_drvdata(hid);
 392         struct mousevsc_dev *input_dev = hv_get_drvdata(dev);
 393
 394         return hid_parse_report(hid, input_dev->report_desc,
 395                                 input_dev->report_desc_size);
 396 }
 397
 398 static int mousevsc_hid_open(struct hid_device *hid)
 399 {
 400         return 0;
 401 }
 402
 403 static int mousevsc_hid_start(struct hid_device *hid)
 404 {
 405         return 0;
 406 }
 407
 408 static void mousevsc_hid_close(struct hid_device *hid)
 409 {
 410 }
 411
 412 static void mousevsc_hid_stop(struct hid_device *hid)
 413 {
 414 }
 415
 416 static int mousevsc_hid_raw_request(struct hid_device *hid,
 417                                     unsigned char report_num,
 418                                     __u8 *buf, size_t len,
 419                                     unsigned char rtype,
 420                                     int reqtype)
 421 {
 422         return 0;
 423 }
 424
 425 static int mousevsc_hid_probe(struct hid_device *hid_dev, const struct hid_device_id *id)
 426 {
 427         int ret;
 428
 429         ret = hid_parse(hid_dev);
 430         if (ret) {
 431                 hid_err(hid_dev, "parse failed\n");
 432                 return ret;
 433         }
 434
 435         ret = hid_hw_start(hid_dev, HID_CONNECT_HIDINPUT | HID_CONNECT_HIDDEV);
 436         if (ret) {
 437                 hid_err(hid_dev, "hw start failed\n");
 438                 return ret;
 439         }
 440
 441         return 0;
 442 }
 443
 444 static const struct hid_ll_driver mousevsc_ll_driver = {
 445         .parse = mousevsc_hid_parse,
 446         .open = mousevsc_hid_open,
 447         .close = mousevsc_hid_close,
 448         .start = mousevsc_hid_start,
 449         .stop = mousevsc_hid_stop,
 450         .raw_request = mousevsc_hid_raw_request,
 451 };
 452
 453 static const struct hid_device_id mousevsc_devices[] = {
 454         { HID_DEVICE(BUS_VIRTUAL, HID_GROUP_ANY, 0x045E, 0x0621) },
 455         { }
 456 };
 457
 458 static struct hid_driver mousevsc_hid_driver = {
 459         .name = "hid-hyperv",
 460         .id_table = mousevsc_devices,
 461         .probe = mousevsc_hid_probe,
 462 };
 463
 464 static int mousevsc_probe(struct hv_device *device,
 465                         const struct hv_vmbus_device_id *dev_id)
 466 {
 467         int ret;
 468         struct mousevsc_dev *input_dev;
 469         struct hid_device *hid_dev;
 470
 471         input_dev = mousevsc_alloc_device(device);
 472
 473         if (!input_dev)
 474                 return -ENOMEM;
 475
 476         ret = vmbus_open(device->channel,
 477                 INPUTVSC_SEND_RING_BUFFER_SIZE,
 478                 INPUTVSC_RECV_RING_BUFFER_SIZE,
 479                 NULL,
 480                 0,
 481                 mousevsc_on_channel_callback,
 482                 device
 483                 );
 484
 485         if (ret)
 486                 goto probe_err0;
 487
 488         ret = mousevsc_connect_to_vsp(device);
 489
 490         if (ret)
 491                 goto probe_err1;
 492
 493         /* workaround SA-167 */
 494         if (input_dev->report_desc[14] == 0x25)
 495                 input_dev->report_desc[14] = 0x29;
 496
 497         hid_dev = hid_allocate_device();
 498         if (IS_ERR(hid_dev)) {
 499                 ret = PTR_ERR(hid_dev);
 500                 goto probe_err1;
 501         }
 502
 503         hid_dev->ll_driver = &mousevsc_ll_driver;
 504         hid_dev->bus = BUS_VIRTUAL;
 505         hid_dev->vendor = input_dev->hid_dev_info.vendor;
 506         hid_dev->product = input_dev->hid_dev_info.product;
 507         hid_dev->version = input_dev->hid_dev_info.version;
 508         input_dev->hid_device = hid_dev;
 509
 510         sprintf(hid_dev->name, "%s", "Microsoft Vmbus HID-compliant Mouse");
 511
 512         hid_set_drvdata(hid_dev, device);
 513
 514         ret = hid_add_device(hid_dev);
 515         if (ret)
 516                 goto probe_err2;
 517
 518         device_init_wakeup(&device->device, true);
 519
 520         input_dev->connected = true;
 521         input_dev->init_complete = true;
 522
 523         return ret;
 524
 525 probe_err2:
 526         hid_destroy_device(hid_dev);
 527
 528 probe_err1:
 529         vmbus_close(device->channel);
 530
 531 probe_err0:
 532         mousevsc_free_device(input_dev);
 533
 534         return ret;
 535 }
 536
 537
 538 static void mousevsc_remove(struct hv_device *dev)
 539 {
 540         struct mousevsc_dev *input_dev = hv_get_drvdata(dev);
 541
 542         device_init_wakeup(&dev->device, false);
 543         vmbus_close(dev->channel);
 544         hid_hw_stop(input_dev->hid_device);
 545         hid_destroy_device(input_dev->hid_device);
 546         mousevsc_free_device(input_dev);
 547 }
 548
 549 static int mousevsc_suspend(struct hv_device *dev)
 550 {
 551         vmbus_close(dev->channel);
 552
 553         return 0;
 554 }
 555
 556 static int mousevsc_resume(struct hv_device *dev)
 557 {
 558         int ret;
 559
 560         ret = vmbus_open(dev->channel,
 561                          INPUTVSC_SEND_RING_BUFFER_SIZE,
 562                          INPUTVSC_RECV_RING_BUFFER_SIZE,
 563                          NULL, 0,
 564                          mousevsc_on_channel_callback,
 565                          dev);
 566         if (ret)
 567                 return ret;
 568
 569         ret = mousevsc_connect_to_vsp(dev);
 570         return ret;
 571 }
 572
 573 static const struct hv_vmbus_device_id id_table[] = {
 574         /* Mouse guid */
 575         { HV_MOUSE_GUID, },
 576         { },
 577 };
 578
 579 MODULE_DEVICE_TABLE(vmbus, id_table);
 580
 581 static struct  hv_driver mousevsc_drv = {
 582         .name = KBUILD_MODNAME,
 583         .id_table = id_table,
 584         .probe = mousevsc_probe,
 585         .remove = mousevsc_remove,
 586         .suspend = mousevsc_suspend,
 587         .resume = mousevsc_resume,
 588         .driver = {
 589                 .probe_type = PROBE_PREFER_ASYNCHRONOUS,
 590         },
 591 };
 592
 593 static int __init mousevsc_init(void)
 594 {
 595         int ret;
 596
 597         ret = hid_register_driver(&mousevsc_hid_driver);
 598         if (ret)
 599                 return ret;
 600
 601         ret = vmbus_driver_register(&mousevsc_drv);
 602         if (ret)
 603                 hid_unregister_driver(&mousevsc_hid_driver);
 604
 605         return ret;
 606 }
 607
 608 static void __exit mousevsc_exit(void)
 609 {
 610         vmbus_driver_unregister(&mousevsc_drv);
 611         hid_unregister_driver(&mousevsc_hid_driver);
 612 }
 613
 614 MODULE_LICENSE("GPL");
 615 MODULE_DESCRIPTION("Microsoft Hyper-V Synthetic HID Driver");
 616
 617 module_init(mousevsc_init);
 618 module_exit(mousevsc_exit);