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
mousevsc_alloc_device(struct hv_device * device)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
mousevsc_free_device(struct mousevsc_dev * device)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
mousevsc_on_receive_device_info(struct mousevsc_dev * input_device,struct synthhid_device_info * device_info)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
mousevsc_on_receive(struct hv_device * device,struct vmpacket_descriptor * packet)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
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
mousevsc_on_channel_callback(void * context)323 static void mousevsc_on_channel_callback(void *context)
324 {
325 struct hv_device *device = context;
326 struct vmpacket_descriptor *desc;
327
328 foreach_vmbus_pkt(desc, device->channel) {
329 switch (desc->type) {
330 case VM_PKT_COMP:
331 break;
332
333 case VM_PKT_DATA_INBAND:
334 mousevsc_on_receive(device, desc);
335 break;
336
337 default:
338 pr_err("Unhandled packet type %d, tid %llx len %d\n",
339 desc->type, desc->trans_id, desc->len8 * 8);
340 break;
341 }
342 }
343 }
344
mousevsc_connect_to_vsp(struct hv_device * device)345 static int mousevsc_connect_to_vsp(struct hv_device *device)
346 {
347 int ret = 0;
348 unsigned long t;
349 struct mousevsc_dev *input_dev = hv_get_drvdata(device);
350 struct mousevsc_prt_msg *request;
351 struct mousevsc_prt_msg *response;
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
mousevsc_hid_parse(struct hid_device * hid)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
mousevsc_hid_open(struct hid_device * hid)412 static int mousevsc_hid_open(struct hid_device *hid)
413 {
414 return 0;
415 }
416
mousevsc_hid_start(struct hid_device * hid)417 static int mousevsc_hid_start(struct hid_device *hid)
418 {
419 return 0;
420 }
421
mousevsc_hid_close(struct hid_device * hid)422 static void mousevsc_hid_close(struct hid_device *hid)
423 {
424 }
425
mousevsc_hid_stop(struct hid_device * hid)426 static void mousevsc_hid_stop(struct hid_device *hid)
427 {
428 }
429
mousevsc_hid_raw_request(struct hid_device * hid,unsigned char report_num,__u8 * buf,size_t len,unsigned char rtype,int reqtype)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
mousevsc_probe(struct hv_device * device,const struct hv_vmbus_device_id * dev_id)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_err2;
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
mousevsc_remove(struct hv_device * dev)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 const struct hv_vmbus_device_id id_table[] = {
553 /* Mouse guid */
554 { HV_MOUSE_GUID, },
555 { },
556 };
557
558 MODULE_DEVICE_TABLE(vmbus, id_table);
559
560 static struct hv_driver mousevsc_drv = {
561 .name = KBUILD_MODNAME,
562 .id_table = id_table,
563 .probe = mousevsc_probe,
564 .remove = mousevsc_remove,
565 .driver = {
566 .probe_type = PROBE_PREFER_ASYNCHRONOUS,
567 },
568 };
569
mousevsc_init(void)570 static int __init mousevsc_init(void)
571 {
572 return vmbus_driver_register(&mousevsc_drv);
573 }
574
mousevsc_exit(void)575 static void __exit mousevsc_exit(void)
576 {
577 vmbus_driver_unregister(&mousevsc_drv);
578 }
579
580 MODULE_LICENSE("GPL");
581 module_init(mousevsc_init);
582 module_exit(mousevsc_exit);
583