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
25struct 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 */
53enum 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 */
65struct synthhid_msg_hdr {
66 enum synthhid_msg_type type;
67 u32 size;
68};
69
70struct synthhid_msg {
71 struct synthhid_msg_hdr header;
72 char data[1]; /* Enclosed message */
73};
74
75union synthhid_version {
76 struct {
77 u16 minor_version;
78 u16 major_version;
79 };
80 u32 version;
81};
82
83/*
84 * Protocol messages
85 */
86struct synthhid_protocol_request {
87 struct synthhid_msg_hdr header;
88 union synthhid_version version_requested;
89};
90
91struct synthhid_protocol_response {
92 struct synthhid_msg_hdr header;
93 union synthhid_version version_requested;
94 unsigned char approved;
95};
96
97struct 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
103struct synthhid_device_info_ack {
104 struct synthhid_msg_hdr header;
105 unsigned char reserved;
106};
107
108struct 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
119enum pipe_prot_msg_type {
120 PIPE_MESSAGE_INVALID,
121 PIPE_MESSAGE_DATA,
122 PIPE_MESSAGE_MAXIMUM
123};
124
125
126struct pipe_prt_msg {
127 enum pipe_prot_msg_type type;
128 u32 size;
129 char data[1];
130};
131
132struct 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 */
145struct 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
164static 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
181static 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
189static 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
247cleanup:
248 complete(&input_device->wait_event);
249
250 return;
251}
252
253static 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
312 pm_wakeup_hard_event(&input_dev->device->device);
313
314 break;
315 default:
316 pr_err("unsupported hid msg type - type %d len %d\n",
317 hid_msg->header.type, hid_msg->header.size);
318 break;
319 }
320
321}
322
323static void mousevsc_on_channel_callback(void *context)
324{
325 const int packet_size = 0x100;
326 int ret;
327 struct hv_device *device = context;
328 u32 bytes_recvd;
329 u64 req_id;
330 struct vmpacket_descriptor *desc;
331 unsigned char *buffer;
332 int bufferlen = packet_size;
333
334 buffer = kmalloc(bufferlen, GFP_ATOMIC);
335 if (!buffer)
336 return;
337
338 do {
339 ret = vmbus_recvpacket_raw(device->channel, buffer,
340 bufferlen, &bytes_recvd, &req_id);
341
342 switch (ret) {
343 case 0:
344 if (bytes_recvd <= 0) {
345 kfree(buffer);
346 return;
347 }
348 desc = (struct vmpacket_descriptor *)buffer;
349
350 switch (desc->type) {
351 case VM_PKT_COMP:
352 break;
353
354 case VM_PKT_DATA_INBAND:
355 mousevsc_on_receive(device, desc);
356 break;
357
358 default:
359 pr_err("unhandled packet type %d, tid %llx len %d\n",
360 desc->type, req_id, bytes_recvd);
361 break;
362 }
363
364 break;
365
366 case -ENOBUFS:
367 kfree(buffer);
368 /* Handle large packet */
369 bufferlen = bytes_recvd;
370 buffer = kmalloc(bytes_recvd, GFP_ATOMIC);
371
372 if (!buffer)
373 return;
374
375 break;
376 }
377 } while (1);
378
379}
380
381static int mousevsc_connect_to_vsp(struct hv_device *device)
382{
383 int ret = 0;
384 unsigned long t;
385 struct mousevsc_dev *input_dev = hv_get_drvdata(device);
386 struct mousevsc_prt_msg *request;
387 struct mousevsc_prt_msg *response;
388
389 request = &input_dev->protocol_req;
390 memset(request, 0, sizeof(struct mousevsc_prt_msg));
391
392 request->type = PIPE_MESSAGE_DATA;
393 request->size = sizeof(struct synthhid_protocol_request);
394 request->request.header.type = SYNTH_HID_PROTOCOL_REQUEST;
395 request->request.header.size = sizeof(unsigned int);
396 request->request.version_requested.version = SYNTHHID_INPUT_VERSION;
397
398 ret = vmbus_sendpacket(device->channel, request,
399 sizeof(struct pipe_prt_msg) -
400 sizeof(unsigned char) +
401 sizeof(struct synthhid_protocol_request),
402 (unsigned long)request,
403 VM_PKT_DATA_INBAND,
404 VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
405 if (ret)
406 goto cleanup;
407
408 t = wait_for_completion_timeout(&input_dev->wait_event, 5*HZ);
409 if (!t) {
410 ret = -ETIMEDOUT;
411 goto cleanup;
412 }
413
414 response = &input_dev->protocol_resp;
415
416 if (!response->response.approved) {
417 pr_err("synthhid protocol request failed (version %d)\n",
418 SYNTHHID_INPUT_VERSION);
419 ret = -ENODEV;
420 goto cleanup;
421 }
422
423 t = wait_for_completion_timeout(&input_dev->wait_event, 5*HZ);
424 if (!t) {
425 ret = -ETIMEDOUT;
426 goto cleanup;
427 }
428
429 /*
430 * We should have gotten the device attr, hid desc and report
431 * desc at this point
432 */
433 ret = input_dev->dev_info_status;
434
435cleanup:
436 return ret;
437}
438
439static int mousevsc_hid_parse(struct hid_device *hid)
440{
441 struct hv_device *dev = hid_get_drvdata(hid);
442 struct mousevsc_dev *input_dev = hv_get_drvdata(dev);
443
444 return hid_parse_report(hid, input_dev->report_desc,
445 input_dev->report_desc_size);
446}
447
448static int mousevsc_hid_open(struct hid_device *hid)
449{
450 return 0;
451}
452
453static int mousevsc_hid_start(struct hid_device *hid)
454{
455 return 0;
456}
457
458static void mousevsc_hid_close(struct hid_device *hid)
459{
460}
461
462static void mousevsc_hid_stop(struct hid_device *hid)
463{
464}
465
466static int mousevsc_hid_raw_request(struct hid_device *hid,
467 unsigned char report_num,
468 __u8 *buf, size_t len,
469 unsigned char rtype,
470 int reqtype)
471{
472 return 0;
473}
474
475static struct hid_ll_driver mousevsc_ll_driver = {
476 .parse = mousevsc_hid_parse,
477 .open = mousevsc_hid_open,
478 .close = mousevsc_hid_close,
479 .start = mousevsc_hid_start,
480 .stop = mousevsc_hid_stop,
481 .raw_request = mousevsc_hid_raw_request,
482};
483
484static struct hid_driver mousevsc_hid_driver;
485
486static int mousevsc_probe(struct hv_device *device,
487 const struct hv_vmbus_device_id *dev_id)
488{
489 int ret;
490 struct mousevsc_dev *input_dev;
491 struct hid_device *hid_dev;
492
493 input_dev = mousevsc_alloc_device(device);
494
495 if (!input_dev)
496 return -ENOMEM;
497
498 ret = vmbus_open(device->channel,
499 INPUTVSC_SEND_RING_BUFFER_SIZE,
500 INPUTVSC_RECV_RING_BUFFER_SIZE,
501 NULL,
502 0,
503 mousevsc_on_channel_callback,
504 device
505 );
506
507 if (ret)
508 goto probe_err0;
509
510 ret = mousevsc_connect_to_vsp(device);
511
512 if (ret)
513 goto probe_err1;
514
515 /* workaround SA-167 */
516 if (input_dev->report_desc[14] == 0x25)
517 input_dev->report_desc[14] = 0x29;
518
519 hid_dev = hid_allocate_device();
520 if (IS_ERR(hid_dev)) {
521 ret = PTR_ERR(hid_dev);
522 goto probe_err1;
523 }
524
525 hid_dev->ll_driver = &mousevsc_ll_driver;
526 hid_dev->driver = &mousevsc_hid_driver;
527 hid_dev->bus = BUS_VIRTUAL;
528 hid_dev->vendor = input_dev->hid_dev_info.vendor;
529 hid_dev->product = input_dev->hid_dev_info.product;
530 hid_dev->version = input_dev->hid_dev_info.version;
531 input_dev->hid_device = hid_dev;
532
533 sprintf(hid_dev->name, "%s", "Microsoft Vmbus HID-compliant Mouse");
534
535 hid_set_drvdata(hid_dev, device);
536
537 ret = hid_add_device(hid_dev);
538 if (ret)
539 goto probe_err1;
540
541
542 ret = hid_parse(hid_dev);
543 if (ret) {
544 hid_err(hid_dev, "parse failed\n");
545 goto probe_err2;
546 }
547
548 ret = hid_hw_start(hid_dev, HID_CONNECT_HIDINPUT | HID_CONNECT_HIDDEV);
549
550 if (ret) {
551 hid_err(hid_dev, "hw start failed\n");
552 goto probe_err2;
553 }
554
555 device_init_wakeup(&device->device, true);
556
557 input_dev->connected = true;
558 input_dev->init_complete = true;
559
560 return ret;
561
562probe_err2:
563 hid_destroy_device(hid_dev);
564
565probe_err1:
566 vmbus_close(device->channel);
567
568probe_err0:
569 mousevsc_free_device(input_dev);
570
571 return ret;
572}
573
574
575static int mousevsc_remove(struct hv_device *dev)
576{
577 struct mousevsc_dev *input_dev = hv_get_drvdata(dev);
578
579 device_init_wakeup(&dev->device, false);
580 vmbus_close(dev->channel);
581 hid_hw_stop(input_dev->hid_device);
582 hid_destroy_device(input_dev->hid_device);
583 mousevsc_free_device(input_dev);
584
585 return 0;
586}
587
588static const struct hv_vmbus_device_id id_table[] = {
589 /* Mouse guid */
590 { HV_MOUSE_GUID, },
591 { },
592};
593
594MODULE_DEVICE_TABLE(vmbus, id_table);
595
596static struct hv_driver mousevsc_drv = {
597 .name = KBUILD_MODNAME,
598 .id_table = id_table,
599 .probe = mousevsc_probe,
600 .remove = mousevsc_remove,
601 .driver = {
602 .probe_type = PROBE_PREFER_ASYNCHRONOUS,
603 },
604};
605
606static int __init mousevsc_init(void)
607{
608 return vmbus_driver_register(&mousevsc_drv);
609}
610
611static void __exit mousevsc_exit(void)
612{
613 vmbus_driver_unregister(&mousevsc_drv);
614}
615
616MODULE_LICENSE("GPL");
617module_init(mousevsc_init);
618module_exit(mousevsc_exit);
619