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         u8                      input_buf[HID_MAX_BUFFER_SIZE];
 161 };
 162
 163
 164 static struct mousevsc_dev *mousevsc_alloc_device(struct hv_device *device)
 165 {
 166         struct mousevsc_dev *input_dev;
 167
 168         input_dev = kzalloc(sizeof(struct mousevsc_dev), GFP_KERNEL);
 169
 170         if (!input_dev)
 171                 return NULL;
 172
 173         input_dev->device = device;
 174         hv_set_drvdata(device, input_dev);
 175         init_completion(&input_dev->wait_event);
 176         input_dev->init_complete = false;
 177
 178         return input_dev;
 179 }
 180
 181 static void mousevsc_free_device(struct mousevsc_dev *device)
 182 {
 183         kfree(device->hid_desc);
 184         kfree(device->report_desc);
 185         hv_set_drvdata(device->device, NULL);
 186         kfree(device);
 187 }
 188
 189 static void mousevsc_on_receive_device_info(struct mousevsc_dev *input_device,
 190                                 struct synthhid_device_info *device_info)
 191 {
 192         int ret = 0;
 193         struct hid_descriptor *desc;
 194         struct mousevsc_prt_msg ack;
 195
 196         input_device->dev_info_status = -ENOMEM;
 197
 198         input_device->hid_dev_info = device_info->hid_dev_info;
 199         desc = &device_info->hid_descriptor;
 200         if (desc->bLength == 0)
 201                 goto cleanup;
 202
 203         input_device->hid_desc = kmemdup(desc, desc->bLength, GFP_ATOMIC);
 204
 205         if (!input_device->hid_desc)
 206                 goto cleanup;
 207
 208         input_device->report_desc_size = desc->desc[0].wDescriptorLength;
 209         if (input_device->report_desc_size == 0) {
 210                 input_device->dev_info_status = -EINVAL;
 211                 goto cleanup;
 212         }
 213
 214         input_device->report_desc = kzalloc(input_device->report_desc_size,
 215                                           GFP_ATOMIC);
 216
 217         if (!input_device->report_desc) {
 218                 input_device->dev_info_status = -ENOMEM;
 219                 goto cleanup;
 220         }
 221
 222         memcpy(input_device->report_desc,
 223                ((unsigned char *)desc) + desc->bLength,
 224                desc->desc[0].wDescriptorLength);
 225
 226         /* Send the ack */
 227         memset(&ack, 0, sizeof(struct mousevsc_prt_msg));
 228
 229         ack.type = PIPE_MESSAGE_DATA;
 230         ack.size = sizeof(struct synthhid_device_info_ack);
 231
 232         ack.ack.header.type = SYNTH_HID_INITIAL_DEVICE_INFO_ACK;
 233         ack.ack.header.size = 1;
 234         ack.ack.reserved = 0;
 235
 236         ret = vmbus_sendpacket(input_device->device->channel,
 237                         &ack,
 238                         sizeof(struct pipe_prt_msg) - sizeof(unsigned char) +
 239                         sizeof(struct synthhid_device_info_ack),
 240                         (unsigned long)&ack,
 241                         VM_PKT_DATA_INBAND,
 242                         VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
 243
 244         if (!ret)
 245                 input_device->dev_info_status = 0;
 246
 247 cleanup:
 248         complete(&input_device->wait_event);
 249
 250         return;
 251 }
 252
 253 static void mousevsc_on_receive(struct hv_device *device,
 254                                 struct vmpacket_descriptor *packet)
 255 {
 256         struct pipe_prt_msg *pipe_msg;
 257         struct synthhid_msg *hid_msg;
 258         struct mousevsc_dev *input_dev = hv_get_drvdata(device);
 259         struct synthhid_input_report *input_report;
 260         size_t len;
 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
 306                 len = min(input_report->header.size,
 307                           (u32)sizeof(input_dev->input_buf));
 308                 memcpy(input_dev->input_buf, input_report->buffer, len);
 309                 hid_input_report(input_dev->hid_device, HID_INPUT_REPORT,
 310                                  input_dev->input_buf, len, 1);
 311                 break;
 312         default:
 313                 pr_err("unsupported hid msg type - type %d len %d",
 314                        hid_msg->header.type, hid_msg->header.size);
 315                 break;
 316         }
 317
 318 }
 319
 320 static void mousevsc_on_channel_callback(void *context)
 321 {
 322         const int packet_size = 0x100;
 323         int ret;
 324         struct hv_device *device = context;
 325         u32 bytes_recvd;
 326         u64 req_id;
 327         struct vmpacket_descriptor *desc;
 328         unsigned char   *buffer;
 329         int     bufferlen = packet_size;
 330
 331         buffer = kmalloc(bufferlen, GFP_ATOMIC);
 332         if (!buffer)
 333                 return;
 334
 335         do {
 336                 ret = vmbus_recvpacket_raw(device->channel, buffer,
 337                                         bufferlen, &bytes_recvd, &req_id);
 338
 339                 switch (ret) {
 340                 case 0:
 341                         if (bytes_recvd <= 0) {
 342                                 kfree(buffer);
 343                                 return;
 344                         }
 345                         desc = (struct vmpacket_descriptor *)buffer;
 346
 347                         switch (desc->type) {
 348                         case VM_PKT_COMP:
 349                                 break;
 350
 351                         case VM_PKT_DATA_INBAND:
 352                                 mousevsc_on_receive(device, desc);
 353                                 break;
 354
 355                         default:
 356                                 pr_err("unhandled packet type %d, tid %llx len %d\n",
 357                                         desc->type, req_id, bytes_recvd);
 358                                 break;
 359                         }
 360
 361                         break;
 362
 363                 case -ENOBUFS:
 364                         kfree(buffer);
 365                         /* Handle large packet */
 366                         bufferlen = bytes_recvd;
 367                         buffer = kmalloc(bytes_recvd, GFP_ATOMIC);
 368
 369                         if (!buffer)
 370                                 return;
 371
 372                         break;
 373                 }
 374         } while (1);
 375
 376 }
 377
 378 static int mousevsc_connect_to_vsp(struct hv_device *device)
 379 {
 380         int ret = 0;
 381         int t;
 382         struct mousevsc_dev *input_dev = hv_get_drvdata(device);
 383         struct mousevsc_prt_msg *request;
 384         struct mousevsc_prt_msg *response;
 385
 386         request = &input_dev->protocol_req;
 387         memset(request, 0, sizeof(struct mousevsc_prt_msg));
 388
 389         request->type = PIPE_MESSAGE_DATA;
 390         request->size = sizeof(struct synthhid_protocol_request);
 391         request->request.header.type = SYNTH_HID_PROTOCOL_REQUEST;
 392         request->request.header.size = sizeof(unsigned int);
 393         request->request.version_requested.version = SYNTHHID_INPUT_VERSION;
 394
 395         ret = vmbus_sendpacket(device->channel, request,
 396                                 sizeof(struct pipe_prt_msg) -
 397                                 sizeof(unsigned char) +
 398                                 sizeof(struct synthhid_protocol_request),
 399                                 (unsigned long)request,
 400                                 VM_PKT_DATA_INBAND,
 401                                 VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
 402         if (ret)
 403                 goto cleanup;
 404
 405         t = wait_for_completion_timeout(&input_dev->wait_event, 5*HZ);
 406         if (!t) {
 407                 ret = -ETIMEDOUT;
 408                 goto cleanup;
 409         }
 410
 411         response = &input_dev->protocol_resp;
 412
 413         if (!response->response.approved) {
 414                 pr_err("synthhid protocol request failed (version %d)\n",
 415                        SYNTHHID_INPUT_VERSION);
 416                 ret = -ENODEV;
 417                 goto cleanup;
 418         }
 419
 420         t = wait_for_completion_timeout(&input_dev->wait_event, 5*HZ);
 421         if (!t) {
 422                 ret = -ETIMEDOUT;
 423                 goto cleanup;
 424         }
 425
 426         /*
 427          * We should have gotten the device attr, hid desc and report
 428          * desc at this point
 429          */
 430         ret = input_dev->dev_info_status;
 431
 432 cleanup:
 433         return ret;
 434 }
 435
 436 static int mousevsc_hid_parse(struct hid_device *hid)
 437 {
 438         struct hv_device *dev = hid_get_drvdata(hid);
 439         struct mousevsc_dev *input_dev = hv_get_drvdata(dev);
 440
 441         return hid_parse_report(hid, input_dev->report_desc,
 442                                 input_dev->report_desc_size);
 443 }
 444
 445 static int mousevsc_hid_open(struct hid_device *hid)
 446 {
 447         return 0;
 448 }
 449
 450 static int mousevsc_hid_start(struct hid_device *hid)
 451 {
 452         return 0;
 453 }
 454
 455 static void mousevsc_hid_close(struct hid_device *hid)
 456 {
 457 }
 458
 459 static void mousevsc_hid_stop(struct hid_device *hid)
 460 {
 461 }
 462
 463 static int mousevsc_hid_raw_request(struct hid_device *hid,
 464                                     unsigned char report_num,
 465                                     __u8 *buf, size_t len,
 466                                     unsigned char rtype,
 467                                     int reqtype)
 468 {
 469         return 0;
 470 }
 471
 472 static struct hid_ll_driver mousevsc_ll_driver = {
 473         .parse = mousevsc_hid_parse,
 474         .open = mousevsc_hid_open,
 475         .close = mousevsc_hid_close,
 476         .start = mousevsc_hid_start,
 477         .stop = mousevsc_hid_stop,
 478         .raw_request = mousevsc_hid_raw_request,
 479 };
 480
 481 static struct hid_driver mousevsc_hid_driver;
 482
 483 static int mousevsc_probe(struct hv_device *device,
 484                         const struct hv_vmbus_device_id *dev_id)
 485 {
 486         int ret;
 487         struct mousevsc_dev *input_dev;
 488         struct hid_device *hid_dev;
 489
 490         input_dev = mousevsc_alloc_device(device);
 491
 492         if (!input_dev)
 493                 return -ENOMEM;
 494
 495         ret = vmbus_open(device->channel,
 496                 INPUTVSC_SEND_RING_BUFFER_SIZE,
 497                 INPUTVSC_RECV_RING_BUFFER_SIZE,
 498                 NULL,
 499                 0,
 500                 mousevsc_on_channel_callback,
 501                 device
 502                 );
 503
 504         if (ret)
 505                 goto probe_err0;
 506
 507         ret = mousevsc_connect_to_vsp(device);
 508
 509         if (ret)
 510                 goto probe_err1;
 511
 512         /* workaround SA-167 */
 513         if (input_dev->report_desc[14] == 0x25)
 514                 input_dev->report_desc[14] = 0x29;
 515
 516         hid_dev = hid_allocate_device();
 517         if (IS_ERR(hid_dev)) {
 518                 ret = PTR_ERR(hid_dev);
 519                 goto probe_err1;
 520         }
 521
 522         hid_dev->ll_driver = &mousevsc_ll_driver;
 523         hid_dev->driver = &mousevsc_hid_driver;
 524         hid_dev->bus = BUS_VIRTUAL;
 525         hid_dev->vendor = input_dev->hid_dev_info.vendor;
 526         hid_dev->product = input_dev->hid_dev_info.product;
 527         hid_dev->version = input_dev->hid_dev_info.version;
 528         input_dev->hid_device = hid_dev;
 529
 530         sprintf(hid_dev->name, "%s", "Microsoft Vmbus HID-compliant Mouse");
 531
 532         hid_set_drvdata(hid_dev, device);
 533
 534         ret = hid_add_device(hid_dev);
 535         if (ret)
 536                 goto probe_err1;
 537
 538
 539         ret = hid_parse(hid_dev);
 540         if (ret) {
 541                 hid_err(hid_dev, "parse failed\n");
 542                 goto probe_err2;
 543         }
 544
 545         ret = hid_hw_start(hid_dev, HID_CONNECT_HIDINPUT | HID_CONNECT_HIDDEV);
 546
 547         if (ret) {
 548                 hid_err(hid_dev, "hw start failed\n");
 549                 goto probe_err2;
 550         }
 551
 552         input_dev->connected = true;
 553         input_dev->init_complete = true;
 554
 555         return ret;
 556
 557 probe_err2:
 558         hid_destroy_device(hid_dev);
 559
 560 probe_err1:
 561         vmbus_close(device->channel);
 562
 563 probe_err0:
 564         mousevsc_free_device(input_dev);
 565
 566         return ret;
 567 }
 568
 569
 570 static int mousevsc_remove(struct hv_device *dev)
 571 {
 572         struct mousevsc_dev *input_dev = hv_get_drvdata(dev);
 573
 574         vmbus_close(dev->channel);
 575         hid_hw_stop(input_dev->hid_device);
 576         hid_destroy_device(input_dev->hid_device);
 577         mousevsc_free_device(input_dev);
 578
 579         return 0;
 580 }
 581
 582 static const struct hv_vmbus_device_id id_table[] = {
 583         /* Mouse guid */
 584         { HV_MOUSE_GUID, },
 585         { },
 586 };
 587
 588 MODULE_DEVICE_TABLE(vmbus, id_table);
 589
 590 static struct  hv_driver mousevsc_drv = {
 591         .name = KBUILD_MODNAME,
 592         .id_table = id_table,
 593         .probe = mousevsc_probe,
 594         .remove = mousevsc_remove,
 595 };
 596
 597 static int __init mousevsc_init(void)
 598 {
 599         return vmbus_driver_register(&mousevsc_drv);
 600 }
 601
 602 static void __exit mousevsc_exit(void)
 603 {
 604         vmbus_driver_unregister(&mousevsc_drv);
 605 }
 606
 607 MODULE_LICENSE("GPL");
 608 module_init(mousevsc_init);
 609 module_exit(mousevsc_exit);