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 = kzalloc(desc->bLength, GFP_ATOMIC);
 203
 204         if (!input_device->hid_desc)
 205                 goto cleanup;
 206
 207         memcpy(input_device->hid_desc, desc, desc->bLength);
 208
 209         input_device->report_desc_size = desc->desc[0].wDescriptorLength;
 210         if (input_device->report_desc_size == 0) {
 211                 input_device->dev_info_status = -EINVAL;
 212                 goto cleanup;
 213         }
 214
 215         input_device->report_desc = kzalloc(input_device->report_desc_size,
 216                                           GFP_ATOMIC);
 217
 218         if (!input_device->report_desc) {
 219                 input_device->dev_info_status = -ENOMEM;
 220                 goto cleanup;
 221         }
 222
 223         memcpy(input_device->report_desc,
 224                ((unsigned char *)desc) + desc->bLength,
 225                desc->desc[0].wDescriptorLength);
 226
 227         /* Send the ack */
 228         memset(&ack, 0, sizeof(struct mousevsc_prt_msg));
 229
 230         ack.type = PIPE_MESSAGE_DATA;
 231         ack.size = sizeof(struct synthhid_device_info_ack);
 232
 233         ack.ack.header.type = SYNTH_HID_INITIAL_DEVICE_INFO_ACK;
 234         ack.ack.header.size = 1;
 235         ack.ack.reserved = 0;
 236
 237         ret = vmbus_sendpacket(input_device->device->channel,
 238                         &ack,
 239                         sizeof(struct pipe_prt_msg) - sizeof(unsigned char) +
 240                         sizeof(struct synthhid_device_info_ack),
 241                         (unsigned long)&ack,
 242                         VM_PKT_DATA_INBAND,
 243                         VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
 244
 245         if (!ret)
 246                 input_device->dev_info_status = 0;
 247
 248 cleanup:
 249         complete(&input_device->wait_event);
 250
 251         return;
 252 }
 253
 254 static void mousevsc_on_receive(struct hv_device *device,
 255                                 struct vmpacket_descriptor *packet)
 256 {
 257         struct pipe_prt_msg *pipe_msg;
 258         struct synthhid_msg *hid_msg;
 259         struct mousevsc_dev *input_dev = hv_get_drvdata(device);
 260         struct synthhid_input_report *input_report;
 261
 262         pipe_msg = (struct pipe_prt_msg *)((unsigned long)packet +
 263                                                 (packet->offset8 << 3));
 264
 265         if (pipe_msg->type != PIPE_MESSAGE_DATA)
 266                 return;
 267
 268         hid_msg = (struct synthhid_msg *)pipe_msg->data;
 269
 270         switch (hid_msg->header.type) {
 271         case SYNTH_HID_PROTOCOL_RESPONSE:
 272                 /*
 273                  * While it will be impossible for us to protect against
 274                  * malicious/buggy hypervisor/host, add a check here to
 275                  * ensure we don't corrupt memory.
 276                  */
 277                 if ((pipe_msg->size + sizeof(struct pipe_prt_msg)
 278                         - sizeof(unsigned char))
 279                         > sizeof(struct mousevsc_prt_msg)) {
 280                         WARN_ON(1);
 281                         break;
 282                 }
 283
 284                 memcpy(&input_dev->protocol_resp, pipe_msg,
 285                        pipe_msg->size + sizeof(struct pipe_prt_msg) -
 286                        sizeof(unsigned char));
 287                 complete(&input_dev->wait_event);
 288                 break;
 289
 290         case SYNTH_HID_INITIAL_DEVICE_INFO:
 291                 WARN_ON(pipe_msg->size < sizeof(struct hv_input_dev_info));
 292
 293                 /*
 294                  * Parse out the device info into device attr,
 295                  * hid desc and report desc
 296                  */
 297                 mousevsc_on_receive_device_info(input_dev,
 298                         (struct synthhid_device_info *)pipe_msg->data);
 299                 break;
 300         case SYNTH_HID_INPUT_REPORT:
 301                 input_report =
 302                         (struct synthhid_input_report *)pipe_msg->data;
 303                 if (!input_dev->init_complete)
 304                         break;
 305                 hid_input_report(input_dev->hid_device,
 306                                 HID_INPUT_REPORT, input_report->buffer,
 307                                 input_report->header.size, 1);
 308                 break;
 309         default:
 310                 pr_err("unsupported hid msg type - type %d len %d",
 311                        hid_msg->header.type, hid_msg->header.size);
 312                 break;
 313         }
 314
 315 }
 316
 317 static void mousevsc_on_channel_callback(void *context)
 318 {
 319         const int packet_size = 0x100;
 320         int ret;
 321         struct hv_device *device = context;
 322         u32 bytes_recvd;
 323         u64 req_id;
 324         struct vmpacket_descriptor *desc;
 325         unsigned char   *buffer;
 326         int     bufferlen = packet_size;
 327
 328         buffer = kmalloc(bufferlen, GFP_ATOMIC);
 329         if (!buffer)
 330                 return;
 331
 332         do {
 333                 ret = vmbus_recvpacket_raw(device->channel, buffer,
 334                                         bufferlen, &bytes_recvd, &req_id);
 335
 336                 switch (ret) {
 337                 case 0:
 338                         if (bytes_recvd <= 0) {
 339                                 kfree(buffer);
 340                                 return;
 341                         }
 342                         desc = (struct vmpacket_descriptor *)buffer;
 343
 344                         switch (desc->type) {
 345                         case VM_PKT_COMP:
 346                                 break;
 347
 348                         case VM_PKT_DATA_INBAND:
 349                                 mousevsc_on_receive(device, desc);
 350                                 break;
 351
 352                         default:
 353                                 pr_err("unhandled packet type %d, tid %llx len %d\n",
 354                                         desc->type, req_id, bytes_recvd);
 355                                 break;
 356                         }
 357
 358                         break;
 359
 360                 case -ENOBUFS:
 361                         kfree(buffer);
 362                         /* Handle large packet */
 363                         bufferlen = bytes_recvd;
 364                         buffer = kmalloc(bytes_recvd, GFP_ATOMIC);
 365
 366                         if (!buffer)
 367                                 return;
 368
 369                         break;
 370                 }
 371         } while (1);
 372
 373 }
 374
 375 static int mousevsc_connect_to_vsp(struct hv_device *device)
 376 {
 377         int ret = 0;
 378         int t;
 379         struct mousevsc_dev *input_dev = hv_get_drvdata(device);
 380         struct mousevsc_prt_msg *request;
 381         struct mousevsc_prt_msg *response;
 382
 383         request = &input_dev->protocol_req;
 384         memset(request, 0, sizeof(struct mousevsc_prt_msg));
 385
 386         request->type = PIPE_MESSAGE_DATA;
 387         request->size = sizeof(struct synthhid_protocol_request);
 388         request->request.header.type = SYNTH_HID_PROTOCOL_REQUEST;
 389         request->request.header.size = sizeof(unsigned int);
 390         request->request.version_requested.version = SYNTHHID_INPUT_VERSION;
 391
 392         ret = vmbus_sendpacket(device->channel, request,
 393                                 sizeof(struct pipe_prt_msg) -
 394                                 sizeof(unsigned char) +
 395                                 sizeof(struct synthhid_protocol_request),
 396                                 (unsigned long)request,
 397                                 VM_PKT_DATA_INBAND,
 398                                 VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
 399         if (ret)
 400                 goto cleanup;
 401
 402         t = wait_for_completion_timeout(&input_dev->wait_event, 5*HZ);
 403         if (!t) {
 404                 ret = -ETIMEDOUT;
 405                 goto cleanup;
 406         }
 407
 408         response = &input_dev->protocol_resp;
 409
 410         if (!response->response.approved) {
 411                 pr_err("synthhid protocol request failed (version %d)\n",
 412                        SYNTHHID_INPUT_VERSION);
 413                 ret = -ENODEV;
 414                 goto cleanup;
 415         }
 416
 417         t = wait_for_completion_timeout(&input_dev->wait_event, 5*HZ);
 418         if (!t) {
 419                 ret = -ETIMEDOUT;
 420                 goto cleanup;
 421         }
 422
 423         /*
 424          * We should have gotten the device attr, hid desc and report
 425          * desc at this point
 426          */
 427         ret = input_dev->dev_info_status;
 428
 429 cleanup:
 430         return ret;
 431 }
 432
 433 static int mousevsc_hid_parse(struct hid_device *hid)
 434 {
 435         struct hv_device *dev = hid_get_drvdata(hid);
 436         struct mousevsc_dev *input_dev = hv_get_drvdata(dev);
 437
 438         return hid_parse_report(hid, input_dev->report_desc,
 439                                 input_dev->report_desc_size);
 440 }
 441
 442 static int mousevsc_hid_open(struct hid_device *hid)
 443 {
 444         return 0;
 445 }
 446
 447 static int mousevsc_hid_start(struct hid_device *hid)
 448 {
 449         return 0;
 450 }
 451
 452 static void mousevsc_hid_close(struct hid_device *hid)
 453 {
 454 }
 455
 456 static void mousevsc_hid_stop(struct hid_device *hid)
 457 {
 458 }
 459
 460 static struct hid_ll_driver mousevsc_ll_driver = {
 461         .parse = mousevsc_hid_parse,
 462         .open = mousevsc_hid_open,
 463         .close = mousevsc_hid_close,
 464         .start = mousevsc_hid_start,
 465         .stop = mousevsc_hid_stop,
 466 };
 467
 468 static struct hid_driver mousevsc_hid_driver;
 469
 470 static int mousevsc_probe(struct hv_device *device,
 471                         const struct hv_vmbus_device_id *dev_id)
 472 {
 473         int ret;
 474         struct mousevsc_dev *input_dev;
 475         struct hid_device *hid_dev;
 476
 477         input_dev = mousevsc_alloc_device(device);
 478
 479         if (!input_dev)
 480                 return -ENOMEM;
 481
 482         ret = vmbus_open(device->channel,
 483                 INPUTVSC_SEND_RING_BUFFER_SIZE,
 484                 INPUTVSC_RECV_RING_BUFFER_SIZE,
 485                 NULL,
 486                 0,
 487                 mousevsc_on_channel_callback,
 488                 device
 489                 );
 490
 491         if (ret)
 492                 goto probe_err0;
 493
 494         ret = mousevsc_connect_to_vsp(device);
 495
 496         if (ret)
 497                 goto probe_err1;
 498
 499         /* workaround SA-167 */
 500         if (input_dev->report_desc[14] == 0x25)
 501                 input_dev->report_desc[14] = 0x29;
 502
 503         hid_dev = hid_allocate_device();
 504         if (IS_ERR(hid_dev)) {
 505                 ret = PTR_ERR(hid_dev);
 506                 goto probe_err1;
 507         }
 508
 509         hid_dev->ll_driver = &mousevsc_ll_driver;
 510         hid_dev->driver = &mousevsc_hid_driver;
 511         hid_dev->bus = BUS_VIRTUAL;
 512         hid_dev->vendor = input_dev->hid_dev_info.vendor;
 513         hid_dev->product = input_dev->hid_dev_info.product;
 514         hid_dev->version = input_dev->hid_dev_info.version;
 515         input_dev->hid_device = hid_dev;
 516
 517         sprintf(hid_dev->name, "%s", "Microsoft Vmbus HID-compliant Mouse");
 518
 519         hid_set_drvdata(hid_dev, device);
 520
 521         ret = hid_add_device(hid_dev);
 522         if (ret)
 523                 goto probe_err1;
 524
 525
 526         ret = hid_parse(hid_dev);
 527         if (ret) {
 528                 hid_err(hid_dev, "parse failed\n");
 529                 goto probe_err2;
 530         }
 531
 532         ret = hid_hw_start(hid_dev, HID_CONNECT_HIDINPUT | HID_CONNECT_HIDDEV);
 533
 534         if (ret) {
 535                 hid_err(hid_dev, "hw start failed\n");
 536                 goto probe_err2;
 537         }
 538
 539         input_dev->connected = true;
 540         input_dev->init_complete = true;
 541
 542         return ret;
 543
 544 probe_err2:
 545         hid_destroy_device(hid_dev);
 546
 547 probe_err1:
 548         vmbus_close(device->channel);
 549
 550 probe_err0:
 551         mousevsc_free_device(input_dev);
 552
 553         return ret;
 554 }
 555
 556
 557 static int mousevsc_remove(struct hv_device *dev)
 558 {
 559         struct mousevsc_dev *input_dev = hv_get_drvdata(dev);
 560
 561         vmbus_close(dev->channel);
 562         hid_hw_stop(input_dev->hid_device);
 563         hid_destroy_device(input_dev->hid_device);
 564         mousevsc_free_device(input_dev);
 565
 566         return 0;
 567 }
 568
 569 static const struct hv_vmbus_device_id id_table[] = {
 570         /* Mouse guid */
 571         { HV_MOUSE_GUID, },
 572         { },
 573 };
 574
 575 MODULE_DEVICE_TABLE(vmbus, id_table);
 576
 577 static struct  hv_driver mousevsc_drv = {
 578         .name = KBUILD_MODNAME,
 579         .id_table = id_table,
 580         .probe = mousevsc_probe,
 581         .remove = mousevsc_remove,
 582 };
 583
 584 static int __init mousevsc_init(void)
 585 {
 586         return vmbus_driver_register(&mousevsc_drv);
 587 }
 588
 589 static void __exit mousevsc_exit(void)
 590 {
 591         vmbus_driver_unregister(&mousevsc_drv);
 592 }
 593
 594 MODULE_LICENSE("GPL");
 595 MODULE_VERSION(HV_DRV_VERSION);
 596 module_init(mousevsc_init);
 597 module_exit(mousevsc_exit);