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 kfree(input_device->hid_desc); 197 input_device->hid_desc = kmemdup(desc, desc->bLength, GFP_ATOMIC); 198 199 if (!input_device->hid_desc) 200 goto cleanup; 201 202 input_device->report_desc_size = desc->desc[0].wDescriptorLength; 203 if (input_device->report_desc_size == 0) { 204 input_device->dev_info_status = -EINVAL; 205 goto cleanup; 206 } 207 208 /* The pointer is not NULL when we resume from hibernation */ 209 kfree(input_device->report_desc); 210 input_device->report_desc = kzalloc(input_device->report_desc_size, 211 GFP_ATOMIC); 212 213 if (!input_device->report_desc) { 214 input_device->dev_info_status = -ENOMEM; 215 goto cleanup; 216 } 217 218 memcpy(input_device->report_desc, 219 ((unsigned char *)desc) + desc->bLength, 220 desc->desc[0].wDescriptorLength); 221 222 /* Send the ack */ 223 memset(&ack, 0, sizeof(struct mousevsc_prt_msg)); 224 225 ack.type = PIPE_MESSAGE_DATA; 226 ack.size = sizeof(struct synthhid_device_info_ack); 227 228 ack.ack.header.type = SYNTH_HID_INITIAL_DEVICE_INFO_ACK; 229 ack.ack.header.size = 1; 230 ack.ack.reserved = 0; 231 232 ret = vmbus_sendpacket(input_device->device->channel, 233 &ack, 234 sizeof(struct pipe_prt_msg) - sizeof(unsigned char) + 235 sizeof(struct synthhid_device_info_ack), 236 (unsigned long)&ack, 237 VM_PKT_DATA_INBAND, 238 VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED); 239 240 if (!ret) 241 input_device->dev_info_status = 0; 242 243 cleanup: 244 complete(&input_device->wait_event); 245 246 return; 247 } 248 249 static void mousevsc_on_receive(struct hv_device *device, 250 struct vmpacket_descriptor *packet) 251 { 252 struct pipe_prt_msg *pipe_msg; 253 struct synthhid_msg *hid_msg; 254 struct mousevsc_dev *input_dev = hv_get_drvdata(device); 255 struct synthhid_input_report *input_report; 256 size_t len; 257 258 pipe_msg = (struct pipe_prt_msg *)((unsigned long)packet + 259 (packet->offset8 << 3)); 260 261 if (pipe_msg->type != PIPE_MESSAGE_DATA) 262 return; 263 264 hid_msg = (struct synthhid_msg *)pipe_msg->data; 265 266 switch (hid_msg->header.type) { 267 case SYNTH_HID_PROTOCOL_RESPONSE: 268 /* 269 * While it will be impossible for us to protect against 270 * malicious/buggy hypervisor/host, add a check here to 271 * ensure we don't corrupt memory. 272 */ 273 if ((pipe_msg->size + sizeof(struct pipe_prt_msg) 274 - sizeof(unsigned char)) 275 > sizeof(struct mousevsc_prt_msg)) { 276 WARN_ON(1); 277 break; 278 } 279 280 memcpy(&input_dev->protocol_resp, pipe_msg, 281 pipe_msg->size + sizeof(struct pipe_prt_msg) - 282 sizeof(unsigned char)); 283 complete(&input_dev->wait_event); 284 break; 285 286 case SYNTH_HID_INITIAL_DEVICE_INFO: 287 WARN_ON(pipe_msg->size < sizeof(struct hv_input_dev_info)); 288 289 /* 290 * Parse out the device info into device attr, 291 * hid desc and report desc 292 */ 293 mousevsc_on_receive_device_info(input_dev, 294 (struct synthhid_device_info *)pipe_msg->data); 295 break; 296 case SYNTH_HID_INPUT_REPORT: 297 input_report = 298 (struct synthhid_input_report *)pipe_msg->data; 299 if (!input_dev->init_complete) 300 break; 301 302 len = min(input_report->header.size, 303 (u32)sizeof(input_dev->input_buf)); 304 memcpy(input_dev->input_buf, input_report->buffer, len); 305 hid_input_report(input_dev->hid_device, HID_INPUT_REPORT, 306 input_dev->input_buf, len, 1); 307 308 pm_wakeup_hard_event(&input_dev->device->device); 309 310 break; 311 default: 312 pr_err("unsupported hid msg type - type %d len %d\n", 313 hid_msg->header.type, hid_msg->header.size); 314 break; 315 } 316 317 } 318 319 static void mousevsc_on_channel_callback(void *context) 320 { 321 struct hv_device *device = context; 322 struct vmpacket_descriptor *desc; 323 324 foreach_vmbus_pkt(desc, device->channel) { 325 switch (desc->type) { 326 case VM_PKT_COMP: 327 break; 328 329 case VM_PKT_DATA_INBAND: 330 mousevsc_on_receive(device, desc); 331 break; 332 333 default: 334 pr_err("Unhandled packet type %d, tid %llx len %d\n", 335 desc->type, desc->trans_id, desc->len8 * 8); 336 break; 337 } 338 } 339 } 340 341 static int mousevsc_connect_to_vsp(struct hv_device *device) 342 { 343 int ret = 0; 344 unsigned long t; 345 struct mousevsc_dev *input_dev = hv_get_drvdata(device); 346 struct mousevsc_prt_msg *request; 347 struct mousevsc_prt_msg *response; 348 349 reinit_completion(&input_dev->wait_event); 350 351 request = &input_dev->protocol_req; 352 memset(request, 0, sizeof(struct mousevsc_prt_msg)); 353 354 request->type = PIPE_MESSAGE_DATA; 355 request->size = sizeof(struct synthhid_protocol_request); 356 request->request.header.type = SYNTH_HID_PROTOCOL_REQUEST; 357 request->request.header.size = sizeof(unsigned int); 358 request->request.version_requested.version = SYNTHHID_INPUT_VERSION; 359 360 ret = vmbus_sendpacket(device->channel, request, 361 sizeof(struct pipe_prt_msg) - 362 sizeof(unsigned char) + 363 sizeof(struct synthhid_protocol_request), 364 (unsigned long)request, 365 VM_PKT_DATA_INBAND, 366 VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED); 367 if (ret) 368 goto cleanup; 369 370 t = wait_for_completion_timeout(&input_dev->wait_event, 5*HZ); 371 if (!t) { 372 ret = -ETIMEDOUT; 373 goto cleanup; 374 } 375 376 response = &input_dev->protocol_resp; 377 378 if (!response->response.approved) { 379 pr_err("synthhid protocol request failed (version %d)\n", 380 SYNTHHID_INPUT_VERSION); 381 ret = -ENODEV; 382 goto cleanup; 383 } 384 385 t = wait_for_completion_timeout(&input_dev->wait_event, 5*HZ); 386 if (!t) { 387 ret = -ETIMEDOUT; 388 goto cleanup; 389 } 390 391 /* 392 * We should have gotten the device attr, hid desc and report 393 * desc at this point 394 */ 395 ret = input_dev->dev_info_status; 396 397 cleanup: 398 return ret; 399 } 400 401 static int mousevsc_hid_parse(struct hid_device *hid) 402 { 403 struct hv_device *dev = hid_get_drvdata(hid); 404 struct mousevsc_dev *input_dev = hv_get_drvdata(dev); 405 406 return hid_parse_report(hid, input_dev->report_desc, 407 input_dev->report_desc_size); 408 } 409 410 static int mousevsc_hid_open(struct hid_device *hid) 411 { 412 return 0; 413 } 414 415 static int mousevsc_hid_start(struct hid_device *hid) 416 { 417 return 0; 418 } 419 420 static void mousevsc_hid_close(struct hid_device *hid) 421 { 422 } 423 424 static void mousevsc_hid_stop(struct hid_device *hid) 425 { 426 } 427 428 static int mousevsc_hid_raw_request(struct hid_device *hid, 429 unsigned char report_num, 430 __u8 *buf, size_t len, 431 unsigned char rtype, 432 int reqtype) 433 { 434 return 0; 435 } 436 437 static struct hid_ll_driver mousevsc_ll_driver = { 438 .parse = mousevsc_hid_parse, 439 .open = mousevsc_hid_open, 440 .close = mousevsc_hid_close, 441 .start = mousevsc_hid_start, 442 .stop = mousevsc_hid_stop, 443 .raw_request = mousevsc_hid_raw_request, 444 }; 445 446 static struct hid_driver mousevsc_hid_driver; 447 448 static int mousevsc_probe(struct hv_device *device, 449 const struct hv_vmbus_device_id *dev_id) 450 { 451 int ret; 452 struct mousevsc_dev *input_dev; 453 struct hid_device *hid_dev; 454 455 input_dev = mousevsc_alloc_device(device); 456 457 if (!input_dev) 458 return -ENOMEM; 459 460 ret = vmbus_open(device->channel, 461 INPUTVSC_SEND_RING_BUFFER_SIZE, 462 INPUTVSC_RECV_RING_BUFFER_SIZE, 463 NULL, 464 0, 465 mousevsc_on_channel_callback, 466 device 467 ); 468 469 if (ret) 470 goto probe_err0; 471 472 ret = mousevsc_connect_to_vsp(device); 473 474 if (ret) 475 goto probe_err1; 476 477 /* workaround SA-167 */ 478 if (input_dev->report_desc[14] == 0x25) 479 input_dev->report_desc[14] = 0x29; 480 481 hid_dev = hid_allocate_device(); 482 if (IS_ERR(hid_dev)) { 483 ret = PTR_ERR(hid_dev); 484 goto probe_err1; 485 } 486 487 hid_dev->ll_driver = &mousevsc_ll_driver; 488 hid_dev->driver = &mousevsc_hid_driver; 489 hid_dev->bus = BUS_VIRTUAL; 490 hid_dev->vendor = input_dev->hid_dev_info.vendor; 491 hid_dev->product = input_dev->hid_dev_info.product; 492 hid_dev->version = input_dev->hid_dev_info.version; 493 input_dev->hid_device = hid_dev; 494 495 sprintf(hid_dev->name, "%s", "Microsoft Vmbus HID-compliant Mouse"); 496 497 hid_set_drvdata(hid_dev, device); 498 499 ret = hid_add_device(hid_dev); 500 if (ret) 501 goto probe_err1; 502 503 504 ret = hid_parse(hid_dev); 505 if (ret) { 506 hid_err(hid_dev, "parse failed\n"); 507 goto probe_err2; 508 } 509 510 ret = hid_hw_start(hid_dev, HID_CONNECT_HIDINPUT | HID_CONNECT_HIDDEV); 511 512 if (ret) { 513 hid_err(hid_dev, "hw start failed\n"); 514 goto probe_err2; 515 } 516 517 device_init_wakeup(&device->device, true); 518 519 input_dev->connected = true; 520 input_dev->init_complete = true; 521 522 return ret; 523 524 probe_err2: 525 hid_destroy_device(hid_dev); 526 527 probe_err1: 528 vmbus_close(device->channel); 529 530 probe_err0: 531 mousevsc_free_device(input_dev); 532 533 return ret; 534 } 535 536 537 static int mousevsc_remove(struct hv_device *dev) 538 { 539 struct mousevsc_dev *input_dev = hv_get_drvdata(dev); 540 541 device_init_wakeup(&dev->device, false); 542 vmbus_close(dev->channel); 543 hid_hw_stop(input_dev->hid_device); 544 hid_destroy_device(input_dev->hid_device); 545 mousevsc_free_device(input_dev); 546 547 return 0; 548 } 549 550 static int mousevsc_suspend(struct hv_device *dev) 551 { 552 vmbus_close(dev->channel); 553 554 return 0; 555 } 556 557 static int mousevsc_resume(struct hv_device *dev) 558 { 559 int ret; 560 561 ret = vmbus_open(dev->channel, 562 INPUTVSC_SEND_RING_BUFFER_SIZE, 563 INPUTVSC_RECV_RING_BUFFER_SIZE, 564 NULL, 0, 565 mousevsc_on_channel_callback, 566 dev); 567 if (ret) 568 return ret; 569 570 ret = mousevsc_connect_to_vsp(dev); 571 return ret; 572 } 573 574 static const struct hv_vmbus_device_id id_table[] = { 575 /* Mouse guid */ 576 { HV_MOUSE_GUID, }, 577 { }, 578 }; 579 580 MODULE_DEVICE_TABLE(vmbus, id_table); 581 582 static struct hv_driver mousevsc_drv = { 583 .name = KBUILD_MODNAME, 584 .id_table = id_table, 585 .probe = mousevsc_probe, 586 .remove = mousevsc_remove, 587 .suspend = mousevsc_suspend, 588 .resume = mousevsc_resume, 589 .driver = { 590 .probe_type = PROBE_PREFER_ASYNCHRONOUS, 591 }, 592 }; 593 594 static int __init mousevsc_init(void) 595 { 596 return vmbus_driver_register(&mousevsc_drv); 597 } 598 599 static void __exit mousevsc_exit(void) 600 { 601 vmbus_driver_unregister(&mousevsc_drv); 602 } 603 604 MODULE_LICENSE("GPL"); 605 MODULE_DESCRIPTION("Microsoft Hyper-V Synthetic HID Driver"); 606 607 module_init(mousevsc_init); 608 module_exit(mousevsc_exit); 609