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                 /*
 262                  * While it will be impossible for us to protect against
 263                  * malicious/buggy hypervisor/host, add a check here to
 264                  * ensure we don't corrupt memory.
 265                  */
 266                 if (struct_size(pipe_msg, data, pipe_msg->size)
 267                         > sizeof(struct mousevsc_prt_msg)) {
 268                         WARN_ON(1);
 269                         break;
 270                 }
 271
 272                 memcpy(&input_dev->protocol_resp, pipe_msg,
 273                                 struct_size(pipe_msg, data, pipe_msg->size));
 274                 complete(&input_dev->wait_event);
 275                 break;
 276
 277         case SYNTH_HID_INITIAL_DEVICE_INFO:
 278                 WARN_ON(pipe_msg->size < sizeof(struct hv_input_dev_info));
 279
 280                 /*
 281                  * Parse out the device info into device attr,
 282                  * hid desc and report desc
 283                  */
 284                 mousevsc_on_receive_device_info(input_dev,
 285                         (struct synthhid_device_info *)pipe_msg->data);
 286                 break;
 287         case SYNTH_HID_INPUT_REPORT:
 288                 input_report =
 289                         (struct synthhid_input_report *)pipe_msg->data;
 290                 if (!input_dev->init_complete)
 291                         break;
 292
 293                 len = min(input_report->header.size,
 294                           (u32)sizeof(input_dev->input_buf));
 295                 memcpy(input_dev->input_buf, input_report->buffer, len);
 296                 hid_input_report(input_dev->hid_device, HID_INPUT_REPORT,
 297                                  input_dev->input_buf, len, 1);
 298
 299                 pm_wakeup_hard_event(&input_dev->device->device);
 300
 301                 break;
 302         default:
 303                 pr_err("unsupported hid msg type - type %d len %d\n",
 304                        hid_msg_hdr->type, hid_msg_hdr->size);
 305                 break;
 306         }
 307
 308 }
 309
 310 static void mousevsc_on_channel_callback(void *context)
 311 {
 312         struct hv_device *device = context;
 313         struct vmpacket_descriptor *desc;
 314
 315         foreach_vmbus_pkt(desc, device->channel) {
 316                 switch (desc->type) {
 317                 case VM_PKT_COMP:
 318                         break;
 319
 320                 case VM_PKT_DATA_INBAND:
 321                         mousevsc_on_receive(device, desc);
 322                         break;
 323
 324                 default:
 325                         pr_err("Unhandled packet type %d, tid %llx len %d\n",
 326                                desc->type, desc->trans_id, desc->len8 * 8);
 327                         break;
 328                 }
 329         }
 330 }
 331
 332 static int mousevsc_connect_to_vsp(struct hv_device *device)
 333 {
 334         int ret = 0;
 335         unsigned long t;
 336         struct mousevsc_dev *input_dev = hv_get_drvdata(device);
 337         struct mousevsc_prt_msg *request;
 338         struct mousevsc_prt_msg *response;
 339
 340         reinit_completion(&input_dev->wait_event);
 341
 342         request = &input_dev->protocol_req;
 343         memset(request, 0, sizeof(struct mousevsc_prt_msg));
 344
 345         request->type = PIPE_MESSAGE_DATA;
 346         request->size = sizeof(struct synthhid_protocol_request);
 347         request->request.header.type = SYNTH_HID_PROTOCOL_REQUEST;
 348         request->request.header.size = sizeof(unsigned int);
 349         request->request.version_requested.version = SYNTHHID_INPUT_VERSION;
 350
 351         ret = vmbus_sendpacket(device->channel, request,
 352                                 sizeof(struct pipe_prt_msg) +
 353                                 sizeof(struct synthhid_protocol_request),
 354                                 (unsigned long)request,
 355                                 VM_PKT_DATA_INBAND,
 356                                 VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
 357         if (ret)
 358                 goto cleanup;
 359
 360         t = wait_for_completion_timeout(&input_dev->wait_event, 5*HZ);
 361         if (!t) {
 362                 ret = -ETIMEDOUT;
 363                 goto cleanup;
 364         }
 365
 366         response = &input_dev->protocol_resp;
 367
 368         if (!response->response.approved) {
 369                 pr_err("synthhid protocol request failed (version %d)\n",
 370                        SYNTHHID_INPUT_VERSION);
 371                 ret = -ENODEV;
 372                 goto cleanup;
 373         }
 374
 375         t = wait_for_completion_timeout(&input_dev->wait_event, 5*HZ);
 376         if (!t) {
 377                 ret = -ETIMEDOUT;
 378                 goto cleanup;
 379         }
 380
 381         /*
 382          * We should have gotten the device attr, hid desc and report
 383          * desc at this point
 384          */
 385         ret = input_dev->dev_info_status;
 386
 387 cleanup:
 388         return ret;
 389 }
 390
 391 static int mousevsc_hid_parse(struct hid_device *hid)
 392 {
 393         struct hv_device *dev = hid_get_drvdata(hid);
 394         struct mousevsc_dev *input_dev = hv_get_drvdata(dev);
 395
 396         return hid_parse_report(hid, input_dev->report_desc,
 397                                 input_dev->report_desc_size);
 398 }
 399
 400 static int mousevsc_hid_open(struct hid_device *hid)
 401 {
 402         return 0;
 403 }
 404
 405 static int mousevsc_hid_start(struct hid_device *hid)
 406 {
 407         return 0;
 408 }
 409
 410 static void mousevsc_hid_close(struct hid_device *hid)
 411 {
 412 }
 413
 414 static void mousevsc_hid_stop(struct hid_device *hid)
 415 {
 416 }
 417
 418 static int mousevsc_hid_raw_request(struct hid_device *hid,
 419                                     unsigned char report_num,
 420                                     __u8 *buf, size_t len,
 421                                     unsigned char rtype,
 422                                     int reqtype)
 423 {
 424         return 0;
 425 }
 426
 427 static struct hid_ll_driver mousevsc_ll_driver = {
 428         .parse = mousevsc_hid_parse,
 429         .open = mousevsc_hid_open,
 430         .close = mousevsc_hid_close,
 431         .start = mousevsc_hid_start,
 432         .stop = mousevsc_hid_stop,
 433         .raw_request = mousevsc_hid_raw_request,
 434 };
 435
 436 static struct hid_driver mousevsc_hid_driver;
 437
 438 static int mousevsc_probe(struct hv_device *device,
 439                         const struct hv_vmbus_device_id *dev_id)
 440 {
 441         int ret;
 442         struct mousevsc_dev *input_dev;
 443         struct hid_device *hid_dev;
 444
 445         input_dev = mousevsc_alloc_device(device);
 446
 447         if (!input_dev)
 448                 return -ENOMEM;
 449
 450         ret = vmbus_open(device->channel,
 451                 INPUTVSC_SEND_RING_BUFFER_SIZE,
 452                 INPUTVSC_RECV_RING_BUFFER_SIZE,
 453                 NULL,
 454                 0,
 455                 mousevsc_on_channel_callback,
 456                 device
 457                 );
 458
 459         if (ret)
 460                 goto probe_err0;
 461
 462         ret = mousevsc_connect_to_vsp(device);
 463
 464         if (ret)
 465                 goto probe_err1;
 466
 467         /* workaround SA-167 */
 468         if (input_dev->report_desc[14] == 0x25)
 469                 input_dev->report_desc[14] = 0x29;
 470
 471         hid_dev = hid_allocate_device();
 472         if (IS_ERR(hid_dev)) {
 473                 ret = PTR_ERR(hid_dev);
 474                 goto probe_err1;
 475         }
 476
 477         hid_dev->ll_driver = &mousevsc_ll_driver;
 478         hid_dev->driver = &mousevsc_hid_driver;
 479         hid_dev->bus = BUS_VIRTUAL;
 480         hid_dev->vendor = input_dev->hid_dev_info.vendor;
 481         hid_dev->product = input_dev->hid_dev_info.product;
 482         hid_dev->version = input_dev->hid_dev_info.version;
 483         input_dev->hid_device = hid_dev;
 484
 485         sprintf(hid_dev->name, "%s", "Microsoft Vmbus HID-compliant Mouse");
 486
 487         hid_set_drvdata(hid_dev, device);
 488
 489         ret = hid_add_device(hid_dev);
 490         if (ret)
 491                 goto probe_err2;
 492
 493
 494         ret = hid_parse(hid_dev);
 495         if (ret) {
 496                 hid_err(hid_dev, "parse failed\n");
 497                 goto probe_err2;
 498         }
 499
 500         ret = hid_hw_start(hid_dev, HID_CONNECT_HIDINPUT | HID_CONNECT_HIDDEV);
 501
 502         if (ret) {
 503                 hid_err(hid_dev, "hw start failed\n");
 504                 goto probe_err2;
 505         }
 506
 507         device_init_wakeup(&device->device, true);
 508
 509         input_dev->connected = true;
 510         input_dev->init_complete = true;
 511
 512         return ret;
 513
 514 probe_err2:
 515         hid_destroy_device(hid_dev);
 516
 517 probe_err1:
 518         vmbus_close(device->channel);
 519
 520 probe_err0:
 521         mousevsc_free_device(input_dev);
 522
 523         return ret;
 524 }
 525
 526
 527 static void mousevsc_remove(struct hv_device *dev)
 528 {
 529         struct mousevsc_dev *input_dev = hv_get_drvdata(dev);
 530
 531         device_init_wakeup(&dev->device, false);
 532         vmbus_close(dev->channel);
 533         hid_hw_stop(input_dev->hid_device);
 534         hid_destroy_device(input_dev->hid_device);
 535         mousevsc_free_device(input_dev);
 536 }
 537
 538 static int mousevsc_suspend(struct hv_device *dev)
 539 {
 540         vmbus_close(dev->channel);
 541
 542         return 0;
 543 }
 544
 545 static int mousevsc_resume(struct hv_device *dev)
 546 {
 547         int ret;
 548
 549         ret = vmbus_open(dev->channel,
 550                          INPUTVSC_SEND_RING_BUFFER_SIZE,
 551                          INPUTVSC_RECV_RING_BUFFER_SIZE,
 552                          NULL, 0,
 553                          mousevsc_on_channel_callback,
 554                          dev);
 555         if (ret)
 556                 return ret;
 557
 558         ret = mousevsc_connect_to_vsp(dev);
 559         return ret;
 560 }
 561
 562 static const struct hv_vmbus_device_id id_table[] = {
 563         /* Mouse guid */
 564         { HV_MOUSE_GUID, },
 565         { },
 566 };
 567
 568 MODULE_DEVICE_TABLE(vmbus, id_table);
 569
 570 static struct  hv_driver mousevsc_drv = {
 571         .name = KBUILD_MODNAME,
 572         .id_table = id_table,
 573         .probe = mousevsc_probe,
 574         .remove = mousevsc_remove,
 575         .suspend = mousevsc_suspend,
 576         .resume = mousevsc_resume,
 577         .driver = {
 578                 .probe_type = PROBE_PREFER_ASYNCHRONOUS,
 579         },
 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_DESCRIPTION("Microsoft Hyper-V Synthetic HID Driver");
 594
 595 module_init(mousevsc_init);
 596 module_exit(mousevsc_exit);