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