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 input_device->hid_desc = kmemdup(desc, desc->bLength, GFP_ATOMIC); 196 197 if (!input_device->hid_desc) 198 goto cleanup; 199 200 input_device->report_desc_size = desc->desc[0].wDescriptorLength; 201 if (input_device->report_desc_size == 0) { 202 input_device->dev_info_status = -EINVAL; 203 goto cleanup; 204 } 205 206 input_device->report_desc = kzalloc(input_device->report_desc_size, 207 GFP_ATOMIC); 208 209 if (!input_device->report_desc) { 210 input_device->dev_info_status = -ENOMEM; 211 goto cleanup; 212 } 213 214 memcpy(input_device->report_desc, 215 ((unsigned char *)desc) + desc->bLength, 216 desc->desc[0].wDescriptorLength); 217 218 /* Send the ack */ 219 memset(&ack, 0, sizeof(struct mousevsc_prt_msg)); 220 221 ack.type = PIPE_MESSAGE_DATA; 222 ack.size = sizeof(struct synthhid_device_info_ack); 223 224 ack.ack.header.type = SYNTH_HID_INITIAL_DEVICE_INFO_ACK; 225 ack.ack.header.size = 1; 226 ack.ack.reserved = 0; 227 228 ret = vmbus_sendpacket(input_device->device->channel, 229 &ack, 230 sizeof(struct pipe_prt_msg) - sizeof(unsigned char) + 231 sizeof(struct synthhid_device_info_ack), 232 (unsigned long)&ack, 233 VM_PKT_DATA_INBAND, 234 VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED); 235 236 if (!ret) 237 input_device->dev_info_status = 0; 238 239 cleanup: 240 complete(&input_device->wait_event); 241 242 return; 243 } 244 245 static void mousevsc_on_receive(struct hv_device *device, 246 struct vmpacket_descriptor *packet) 247 { 248 struct pipe_prt_msg *pipe_msg; 249 struct synthhid_msg *hid_msg; 250 struct mousevsc_dev *input_dev = hv_get_drvdata(device); 251 struct synthhid_input_report *input_report; 252 size_t len; 253 254 pipe_msg = (struct pipe_prt_msg *)((unsigned long)packet + 255 (packet->offset8 << 3)); 256 257 if (pipe_msg->type != PIPE_MESSAGE_DATA) 258 return; 259 260 hid_msg = (struct synthhid_msg *)pipe_msg->data; 261 262 switch (hid_msg->header.type) { 263 case SYNTH_HID_PROTOCOL_RESPONSE: 264 /* 265 * While it will be impossible for us to protect against 266 * malicious/buggy hypervisor/host, add a check here to 267 * ensure we don't corrupt memory. 268 */ 269 if ((pipe_msg->size + sizeof(struct pipe_prt_msg) 270 - sizeof(unsigned char)) 271 > sizeof(struct mousevsc_prt_msg)) { 272 WARN_ON(1); 273 break; 274 } 275 276 memcpy(&input_dev->protocol_resp, pipe_msg, 277 pipe_msg->size + sizeof(struct pipe_prt_msg) - 278 sizeof(unsigned char)); 279 complete(&input_dev->wait_event); 280 break; 281 282 case SYNTH_HID_INITIAL_DEVICE_INFO: 283 WARN_ON(pipe_msg->size < sizeof(struct hv_input_dev_info)); 284 285 /* 286 * Parse out the device info into device attr, 287 * hid desc and report desc 288 */ 289 mousevsc_on_receive_device_info(input_dev, 290 (struct synthhid_device_info *)pipe_msg->data); 291 break; 292 case SYNTH_HID_INPUT_REPORT: 293 input_report = 294 (struct synthhid_input_report *)pipe_msg->data; 295 if (!input_dev->init_complete) 296 break; 297 298 len = min(input_report->header.size, 299 (u32)sizeof(input_dev->input_buf)); 300 memcpy(input_dev->input_buf, input_report->buffer, len); 301 hid_input_report(input_dev->hid_device, HID_INPUT_REPORT, 302 input_dev->input_buf, len, 1); 303 304 pm_wakeup_hard_event(&input_dev->device->device); 305 306 break; 307 default: 308 pr_err("unsupported hid msg type - type %d len %d\n", 309 hid_msg->header.type, hid_msg->header.size); 310 break; 311 } 312 313 } 314 315 static void mousevsc_on_channel_callback(void *context) 316 { 317 struct hv_device *device = context; 318 struct vmpacket_descriptor *desc; 319 320 foreach_vmbus_pkt(desc, device->channel) { 321 switch (desc->type) { 322 case VM_PKT_COMP: 323 break; 324 325 case VM_PKT_DATA_INBAND: 326 mousevsc_on_receive(device, desc); 327 break; 328 329 default: 330 pr_err("Unhandled packet type %d, tid %llx len %d\n", 331 desc->type, desc->trans_id, desc->len8 * 8); 332 break; 333 } 334 } 335 } 336 337 static int mousevsc_connect_to_vsp(struct hv_device *device) 338 { 339 int ret = 0; 340 unsigned long t; 341 struct mousevsc_dev *input_dev = hv_get_drvdata(device); 342 struct mousevsc_prt_msg *request; 343 struct mousevsc_prt_msg *response; 344 345 request = &input_dev->protocol_req; 346 memset(request, 0, sizeof(struct mousevsc_prt_msg)); 347 348 request->type = PIPE_MESSAGE_DATA; 349 request->size = sizeof(struct synthhid_protocol_request); 350 request->request.header.type = SYNTH_HID_PROTOCOL_REQUEST; 351 request->request.header.size = sizeof(unsigned int); 352 request->request.version_requested.version = SYNTHHID_INPUT_VERSION; 353 354 ret = vmbus_sendpacket(device->channel, request, 355 sizeof(struct pipe_prt_msg) - 356 sizeof(unsigned char) + 357 sizeof(struct synthhid_protocol_request), 358 (unsigned long)request, 359 VM_PKT_DATA_INBAND, 360 VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED); 361 if (ret) 362 goto cleanup; 363 364 t = wait_for_completion_timeout(&input_dev->wait_event, 5*HZ); 365 if (!t) { 366 ret = -ETIMEDOUT; 367 goto cleanup; 368 } 369 370 response = &input_dev->protocol_resp; 371 372 if (!response->response.approved) { 373 pr_err("synthhid protocol request failed (version %d)\n", 374 SYNTHHID_INPUT_VERSION); 375 ret = -ENODEV; 376 goto cleanup; 377 } 378 379 t = wait_for_completion_timeout(&input_dev->wait_event, 5*HZ); 380 if (!t) { 381 ret = -ETIMEDOUT; 382 goto cleanup; 383 } 384 385 /* 386 * We should have gotten the device attr, hid desc and report 387 * desc at this point 388 */ 389 ret = input_dev->dev_info_status; 390 391 cleanup: 392 return ret; 393 } 394 395 static int mousevsc_hid_parse(struct hid_device *hid) 396 { 397 struct hv_device *dev = hid_get_drvdata(hid); 398 struct mousevsc_dev *input_dev = hv_get_drvdata(dev); 399 400 return hid_parse_report(hid, input_dev->report_desc, 401 input_dev->report_desc_size); 402 } 403 404 static int mousevsc_hid_open(struct hid_device *hid) 405 { 406 return 0; 407 } 408 409 static int mousevsc_hid_start(struct hid_device *hid) 410 { 411 return 0; 412 } 413 414 static void mousevsc_hid_close(struct hid_device *hid) 415 { 416 } 417 418 static void mousevsc_hid_stop(struct hid_device *hid) 419 { 420 } 421 422 static int mousevsc_hid_raw_request(struct hid_device *hid, 423 unsigned char report_num, 424 __u8 *buf, size_t len, 425 unsigned char rtype, 426 int reqtype) 427 { 428 return 0; 429 } 430 431 static struct hid_ll_driver mousevsc_ll_driver = { 432 .parse = mousevsc_hid_parse, 433 .open = mousevsc_hid_open, 434 .close = mousevsc_hid_close, 435 .start = mousevsc_hid_start, 436 .stop = mousevsc_hid_stop, 437 .raw_request = mousevsc_hid_raw_request, 438 }; 439 440 static struct hid_driver mousevsc_hid_driver; 441 442 static int mousevsc_probe(struct hv_device *device, 443 const struct hv_vmbus_device_id *dev_id) 444 { 445 int ret; 446 struct mousevsc_dev *input_dev; 447 struct hid_device *hid_dev; 448 449 input_dev = mousevsc_alloc_device(device); 450 451 if (!input_dev) 452 return -ENOMEM; 453 454 ret = vmbus_open(device->channel, 455 INPUTVSC_SEND_RING_BUFFER_SIZE, 456 INPUTVSC_RECV_RING_BUFFER_SIZE, 457 NULL, 458 0, 459 mousevsc_on_channel_callback, 460 device 461 ); 462 463 if (ret) 464 goto probe_err0; 465 466 ret = mousevsc_connect_to_vsp(device); 467 468 if (ret) 469 goto probe_err1; 470 471 /* workaround SA-167 */ 472 if (input_dev->report_desc[14] == 0x25) 473 input_dev->report_desc[14] = 0x29; 474 475 hid_dev = hid_allocate_device(); 476 if (IS_ERR(hid_dev)) { 477 ret = PTR_ERR(hid_dev); 478 goto probe_err1; 479 } 480 481 hid_dev->ll_driver = &mousevsc_ll_driver; 482 hid_dev->driver = &mousevsc_hid_driver; 483 hid_dev->bus = BUS_VIRTUAL; 484 hid_dev->vendor = input_dev->hid_dev_info.vendor; 485 hid_dev->product = input_dev->hid_dev_info.product; 486 hid_dev->version = input_dev->hid_dev_info.version; 487 input_dev->hid_device = hid_dev; 488 489 sprintf(hid_dev->name, "%s", "Microsoft Vmbus HID-compliant Mouse"); 490 491 hid_set_drvdata(hid_dev, device); 492 493 ret = hid_add_device(hid_dev); 494 if (ret) 495 goto probe_err1; 496 497 498 ret = hid_parse(hid_dev); 499 if (ret) { 500 hid_err(hid_dev, "parse failed\n"); 501 goto probe_err2; 502 } 503 504 ret = hid_hw_start(hid_dev, HID_CONNECT_HIDINPUT | HID_CONNECT_HIDDEV); 505 506 if (ret) { 507 hid_err(hid_dev, "hw start failed\n"); 508 goto probe_err2; 509 } 510 511 device_init_wakeup(&device->device, true); 512 513 input_dev->connected = true; 514 input_dev->init_complete = true; 515 516 return ret; 517 518 probe_err2: 519 hid_destroy_device(hid_dev); 520 521 probe_err1: 522 vmbus_close(device->channel); 523 524 probe_err0: 525 mousevsc_free_device(input_dev); 526 527 return ret; 528 } 529 530 531 static int mousevsc_remove(struct hv_device *dev) 532 { 533 struct mousevsc_dev *input_dev = hv_get_drvdata(dev); 534 535 device_init_wakeup(&dev->device, false); 536 vmbus_close(dev->channel); 537 hid_hw_stop(input_dev->hid_device); 538 hid_destroy_device(input_dev->hid_device); 539 mousevsc_free_device(input_dev); 540 541 return 0; 542 } 543 544 static const struct hv_vmbus_device_id id_table[] = { 545 /* Mouse guid */ 546 { HV_MOUSE_GUID, }, 547 { }, 548 }; 549 550 MODULE_DEVICE_TABLE(vmbus, id_table); 551 552 static struct hv_driver mousevsc_drv = { 553 .name = KBUILD_MODNAME, 554 .id_table = id_table, 555 .probe = mousevsc_probe, 556 .remove = mousevsc_remove, 557 .driver = { 558 .probe_type = PROBE_PREFER_ASYNCHRONOUS, 559 }, 560 }; 561 562 static int __init mousevsc_init(void) 563 { 564 return vmbus_driver_register(&mousevsc_drv); 565 } 566 567 static void __exit mousevsc_exit(void) 568 { 569 vmbus_driver_unregister(&mousevsc_drv); 570 } 571 572 MODULE_LICENSE("GPL"); 573 MODULE_DESCRIPTION("Microsoft Hyper-V Synthetic HID Driver"); 574 575 module_init(mousevsc_init); 576 module_exit(mousevsc_exit); 577