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v6.8
  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 *  Copyright (c) 2013, Microsoft Corporation.
  4 */
  5
  6#include <linux/init.h>
  7#include <linux/module.h>
  8#include <linux/device.h>
  9#include <linux/completion.h>
 10#include <linux/hyperv.h>
 11#include <linux/serio.h>
 12#include <linux/slab.h>
 13
 14/*
 15 * Current version 1.0
 16 *
 17 */
 18#define SYNTH_KBD_VERSION_MAJOR 1
 19#define SYNTH_KBD_VERSION_MINOR	0
 20#define SYNTH_KBD_VERSION		(SYNTH_KBD_VERSION_MINOR | \
 21					 (SYNTH_KBD_VERSION_MAJOR << 16))
 22
 23
 24/*
 25 * Message types in the synthetic input protocol
 26 */
 27enum synth_kbd_msg_type {
 28	SYNTH_KBD_PROTOCOL_REQUEST = 1,
 29	SYNTH_KBD_PROTOCOL_RESPONSE = 2,
 30	SYNTH_KBD_EVENT = 3,
 31	SYNTH_KBD_LED_INDICATORS = 4,
 32};
 33
 34/*
 35 * Basic message structures.
 36 */
 37struct synth_kbd_msg_hdr {
 38	__le32 type;
 39};
 40
 41struct synth_kbd_msg {
 42	struct synth_kbd_msg_hdr header;
 43	char data[]; /* Enclosed message */
 44};
 45
 46union synth_kbd_version {
 47	__le32 version;
 48};
 49
 50/*
 51 * Protocol messages
 52 */
 53struct synth_kbd_protocol_request {
 54	struct synth_kbd_msg_hdr header;
 55	union synth_kbd_version version_requested;
 56};
 57
 58#define PROTOCOL_ACCEPTED	BIT(0)
 59struct synth_kbd_protocol_response {
 60	struct synth_kbd_msg_hdr header;
 61	__le32 proto_status;
 62};
 63
 64#define IS_UNICODE	BIT(0)
 65#define IS_BREAK	BIT(1)
 66#define IS_E0		BIT(2)
 67#define IS_E1		BIT(3)
 68struct synth_kbd_keystroke {
 69	struct synth_kbd_msg_hdr header;
 70	__le16 make_code;
 71	__le16 reserved0;
 72	__le32 info; /* Additional information */
 73};
 74
 75
 76#define HK_MAXIMUM_MESSAGE_SIZE 256
 77
 78#define KBD_VSC_SEND_RING_BUFFER_SIZE	VMBUS_RING_SIZE(36 * 1024)
 79#define KBD_VSC_RECV_RING_BUFFER_SIZE	VMBUS_RING_SIZE(36 * 1024)
 80
 81#define XTKBD_EMUL0     0xe0
 82#define XTKBD_EMUL1     0xe1
 83#define XTKBD_RELEASE   0x80
 84
 85
 86/*
 87 * Represents a keyboard device
 88 */
 89struct hv_kbd_dev {
 90	struct hv_device *hv_dev;
 91	struct serio *hv_serio;
 92	struct synth_kbd_protocol_request protocol_req;
 93	struct synth_kbd_protocol_response protocol_resp;
 94	/* Synchronize the request/response if needed */
 95	struct completion wait_event;
 96	spinlock_t lock; /* protects 'started' field */
 97	bool started;
 98};
 99
100static void hv_kbd_on_receive(struct hv_device *hv_dev,
101			      struct synth_kbd_msg *msg, u32 msg_length)
102{
103	struct hv_kbd_dev *kbd_dev = hv_get_drvdata(hv_dev);
104	struct synth_kbd_keystroke *ks_msg;
105	unsigned long flags;
106	u32 msg_type = __le32_to_cpu(msg->header.type);
107	u32 info;
108	u16 scan_code;
109
110	switch (msg_type) {
111	case SYNTH_KBD_PROTOCOL_RESPONSE:
112		/*
113		 * Validate the information provided by the host.
114		 * If the host is giving us a bogus packet,
115		 * drop the packet (hoping the problem
116		 * goes away).
117		 */
118		if (msg_length < sizeof(struct synth_kbd_protocol_response)) {
119			dev_err(&hv_dev->device,
120				"Illegal protocol response packet (len: %d)\n",
121				msg_length);
122			break;
123		}
124
125		memcpy(&kbd_dev->protocol_resp, msg,
126			sizeof(struct synth_kbd_protocol_response));
127		complete(&kbd_dev->wait_event);
128		break;
129
130	case SYNTH_KBD_EVENT:
131		/*
132		 * Validate the information provided by the host.
133		 * If the host is giving us a bogus packet,
134		 * drop the packet (hoping the problem
135		 * goes away).
136		 */
137		if (msg_length < sizeof(struct  synth_kbd_keystroke)) {
138			dev_err(&hv_dev->device,
139				"Illegal keyboard event packet (len: %d)\n",
140				msg_length);
141			break;
142		}
143
144		ks_msg = (struct synth_kbd_keystroke *)msg;
145		info = __le32_to_cpu(ks_msg->info);
146
147		/*
148		 * Inject the information through the serio interrupt.
149		 */
150		spin_lock_irqsave(&kbd_dev->lock, flags);
151		if (kbd_dev->started) {
152			if (info & IS_E0)
153				serio_interrupt(kbd_dev->hv_serio,
154						XTKBD_EMUL0, 0);
155			if (info & IS_E1)
156				serio_interrupt(kbd_dev->hv_serio,
157						XTKBD_EMUL1, 0);
158			scan_code = __le16_to_cpu(ks_msg->make_code);
159			if (info & IS_BREAK)
160				scan_code |= XTKBD_RELEASE;
161
162			serio_interrupt(kbd_dev->hv_serio, scan_code, 0);
 
 
163		}
164		spin_unlock_irqrestore(&kbd_dev->lock, flags);
165
166		/*
167		 * Only trigger a wakeup on key down, otherwise
168		 * "echo freeze > /sys/power/state" can't really enter the
169		 * state because the Enter-UP can trigger a wakeup at once.
170		 */
171		if (!(info & IS_BREAK))
172			pm_wakeup_hard_event(&hv_dev->device);
173
174		break;
175
176	default:
177		dev_err(&hv_dev->device,
178			"unhandled message type %d\n", msg_type);
179	}
180}
181
182static void hv_kbd_handle_received_packet(struct hv_device *hv_dev,
183					  struct vmpacket_descriptor *desc,
184					  u32 bytes_recvd,
185					  u64 req_id)
186{
187	struct synth_kbd_msg *msg;
188	u32 msg_sz;
189
190	switch (desc->type) {
191	case VM_PKT_COMP:
192		break;
193
194	case VM_PKT_DATA_INBAND:
195		/*
196		 * We have a packet that has "inband" data. The API used
197		 * for retrieving the packet guarantees that the complete
198		 * packet is read. So, minimally, we should be able to
199		 * parse the payload header safely (assuming that the host
200		 * can be trusted.  Trusting the host seems to be a
201		 * reasonable assumption because in a virtualized
202		 * environment there is not whole lot you can do if you
203		 * don't trust the host.
204		 *
205		 * Nonetheless, let us validate if the host can be trusted
206		 * (in a trivial way).  The interesting aspect of this
207		 * validation is how do you recover if we discover that the
208		 * host is not to be trusted? Simply dropping the packet, I
209		 * don't think is an appropriate recovery.  In the interest
210		 * of failing fast, it may be better to crash the guest.
211		 * For now, I will just drop the packet!
212		 */
213
214		msg_sz = bytes_recvd - (desc->offset8 << 3);
215		if (msg_sz <= sizeof(struct synth_kbd_msg_hdr)) {
216			/*
217			 * Drop the packet and hope
218			 * the problem magically goes away.
219			 */
220			dev_err(&hv_dev->device,
221				"Illegal packet (type: %d, tid: %llx, size: %d)\n",
222				desc->type, req_id, msg_sz);
223			break;
224		}
225
226		msg = (void *)desc + (desc->offset8 << 3);
227		hv_kbd_on_receive(hv_dev, msg, msg_sz);
228		break;
229
230	default:
231		dev_err(&hv_dev->device,
232			"unhandled packet type %d, tid %llx len %d\n",
233			desc->type, req_id, bytes_recvd);
234		break;
235	}
236}
237
238static void hv_kbd_on_channel_callback(void *context)
239{
240	struct vmpacket_descriptor *desc;
241	struct hv_device *hv_dev = context;
242	u32 bytes_recvd;
243	u64 req_id;
244
245	foreach_vmbus_pkt(desc, hv_dev->channel) {
246		bytes_recvd = desc->len8 * 8;
247		req_id = desc->trans_id;
248
249		hv_kbd_handle_received_packet(hv_dev, desc, bytes_recvd,
250					      req_id);
251	}
252}
253
254static int hv_kbd_connect_to_vsp(struct hv_device *hv_dev)
255{
256	struct hv_kbd_dev *kbd_dev = hv_get_drvdata(hv_dev);
257	struct synth_kbd_protocol_request *request;
258	struct synth_kbd_protocol_response *response;
259	u32 proto_status;
260	int error;
261
262	reinit_completion(&kbd_dev->wait_event);
263
264	request = &kbd_dev->protocol_req;
265	memset(request, 0, sizeof(struct synth_kbd_protocol_request));
266	request->header.type = __cpu_to_le32(SYNTH_KBD_PROTOCOL_REQUEST);
267	request->version_requested.version = __cpu_to_le32(SYNTH_KBD_VERSION);
268
269	error = vmbus_sendpacket(hv_dev->channel, request,
270				 sizeof(struct synth_kbd_protocol_request),
271				 (unsigned long)request,
272				 VM_PKT_DATA_INBAND,
273				 VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
274	if (error)
275		return error;
276
277	if (!wait_for_completion_timeout(&kbd_dev->wait_event, 10 * HZ))
278		return -ETIMEDOUT;
279
280	response = &kbd_dev->protocol_resp;
281	proto_status = __le32_to_cpu(response->proto_status);
282	if (!(proto_status & PROTOCOL_ACCEPTED)) {
283		dev_err(&hv_dev->device,
284			"synth_kbd protocol request failed (version %d)\n",
285		        SYNTH_KBD_VERSION);
286		return -ENODEV;
287	}
288
289	return 0;
290}
291
292static int hv_kbd_start(struct serio *serio)
293{
294	struct hv_kbd_dev *kbd_dev = serio->port_data;
295	unsigned long flags;
296
297	spin_lock_irqsave(&kbd_dev->lock, flags);
 
298	kbd_dev->started = true;
299	spin_unlock_irqrestore(&kbd_dev->lock, flags);
300
301	return 0;
302}
303
304static void hv_kbd_stop(struct serio *serio)
305{
306	struct hv_kbd_dev *kbd_dev = serio->port_data;
307	unsigned long flags;
308
309	spin_lock_irqsave(&kbd_dev->lock, flags);
 
310	kbd_dev->started = false;
311	spin_unlock_irqrestore(&kbd_dev->lock, flags);
312}
313
314static int hv_kbd_probe(struct hv_device *hv_dev,
315			const struct hv_vmbus_device_id *dev_id)
316{
317	struct hv_kbd_dev *kbd_dev;
318	struct serio *hv_serio;
319	int error;
320
321	kbd_dev = kzalloc(sizeof(struct hv_kbd_dev), GFP_KERNEL);
322	hv_serio = kzalloc(sizeof(struct serio), GFP_KERNEL);
323	if (!kbd_dev || !hv_serio) {
324		error = -ENOMEM;
325		goto err_free_mem;
326	}
327
328	kbd_dev->hv_dev = hv_dev;
329	kbd_dev->hv_serio = hv_serio;
330	spin_lock_init(&kbd_dev->lock);
331	init_completion(&kbd_dev->wait_event);
332	hv_set_drvdata(hv_dev, kbd_dev);
333
334	hv_serio->dev.parent  = &hv_dev->device;
335	hv_serio->id.type = SERIO_8042_XL;
336	hv_serio->port_data = kbd_dev;
337	strscpy(hv_serio->name, dev_name(&hv_dev->device),
338		sizeof(hv_serio->name));
339	strscpy(hv_serio->phys, dev_name(&hv_dev->device),
340		sizeof(hv_serio->phys));
341
342	hv_serio->start = hv_kbd_start;
343	hv_serio->stop = hv_kbd_stop;
344
345	error = vmbus_open(hv_dev->channel,
346			   KBD_VSC_SEND_RING_BUFFER_SIZE,
347			   KBD_VSC_RECV_RING_BUFFER_SIZE,
348			   NULL, 0,
349			   hv_kbd_on_channel_callback,
350			   hv_dev);
351	if (error)
352		goto err_free_mem;
353
354	error = hv_kbd_connect_to_vsp(hv_dev);
355	if (error)
356		goto err_close_vmbus;
357
358	serio_register_port(kbd_dev->hv_serio);
359
360	device_init_wakeup(&hv_dev->device, true);
361
362	return 0;
363
364err_close_vmbus:
365	vmbus_close(hv_dev->channel);
366err_free_mem:
367	kfree(hv_serio);
368	kfree(kbd_dev);
369	return error;
370}
371
372static void hv_kbd_remove(struct hv_device *hv_dev)
373{
374	struct hv_kbd_dev *kbd_dev = hv_get_drvdata(hv_dev);
375
376	serio_unregister_port(kbd_dev->hv_serio);
377	vmbus_close(hv_dev->channel);
378	kfree(kbd_dev);
379
380	hv_set_drvdata(hv_dev, NULL);
381}
382
383static int hv_kbd_suspend(struct hv_device *hv_dev)
384{
385	vmbus_close(hv_dev->channel);
386
387	return 0;
388}
389
390static int hv_kbd_resume(struct hv_device *hv_dev)
391{
392	int ret;
393
394	ret = vmbus_open(hv_dev->channel,
395			 KBD_VSC_SEND_RING_BUFFER_SIZE,
396			 KBD_VSC_RECV_RING_BUFFER_SIZE,
397			 NULL, 0,
398			 hv_kbd_on_channel_callback,
399			 hv_dev);
400	if (ret == 0)
401		ret = hv_kbd_connect_to_vsp(hv_dev);
402
403	return ret;
404}
405
406static const struct hv_vmbus_device_id id_table[] = {
407	/* Keyboard guid */
408	{ HV_KBD_GUID, },
409	{ },
410};
411
412MODULE_DEVICE_TABLE(vmbus, id_table);
413
414static struct  hv_driver hv_kbd_drv = {
415	.name = KBUILD_MODNAME,
416	.id_table = id_table,
417	.probe = hv_kbd_probe,
418	.remove = hv_kbd_remove,
419	.suspend = hv_kbd_suspend,
420	.resume = hv_kbd_resume,
421	.driver = {
422		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
423	},
424};
425
426static int __init hv_kbd_init(void)
427{
428	return vmbus_driver_register(&hv_kbd_drv);
429}
430
431static void __exit hv_kbd_exit(void)
432{
433	vmbus_driver_unregister(&hv_kbd_drv);
434}
435
436MODULE_LICENSE("GPL");
437MODULE_DESCRIPTION("Microsoft Hyper-V Synthetic Keyboard Driver");
438
439module_init(hv_kbd_init);
440module_exit(hv_kbd_exit);
v6.13.7
  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 *  Copyright (c) 2013, Microsoft Corporation.
  4 */
  5
  6#include <linux/init.h>
  7#include <linux/module.h>
  8#include <linux/device.h>
  9#include <linux/completion.h>
 10#include <linux/hyperv.h>
 11#include <linux/serio.h>
 12#include <linux/slab.h>
 13
 14/*
 15 * Current version 1.0
 16 *
 17 */
 18#define SYNTH_KBD_VERSION_MAJOR 1
 19#define SYNTH_KBD_VERSION_MINOR	0
 20#define SYNTH_KBD_VERSION		(SYNTH_KBD_VERSION_MINOR | \
 21					 (SYNTH_KBD_VERSION_MAJOR << 16))
 22
 23
 24/*
 25 * Message types in the synthetic input protocol
 26 */
 27enum synth_kbd_msg_type {
 28	SYNTH_KBD_PROTOCOL_REQUEST = 1,
 29	SYNTH_KBD_PROTOCOL_RESPONSE = 2,
 30	SYNTH_KBD_EVENT = 3,
 31	SYNTH_KBD_LED_INDICATORS = 4,
 32};
 33
 34/*
 35 * Basic message structures.
 36 */
 37struct synth_kbd_msg_hdr {
 38	__le32 type;
 39};
 40
 41struct synth_kbd_msg {
 42	struct synth_kbd_msg_hdr header;
 43	char data[]; /* Enclosed message */
 44};
 45
 46union synth_kbd_version {
 47	__le32 version;
 48};
 49
 50/*
 51 * Protocol messages
 52 */
 53struct synth_kbd_protocol_request {
 54	struct synth_kbd_msg_hdr header;
 55	union synth_kbd_version version_requested;
 56};
 57
 58#define PROTOCOL_ACCEPTED	BIT(0)
 59struct synth_kbd_protocol_response {
 60	struct synth_kbd_msg_hdr header;
 61	__le32 proto_status;
 62};
 63
 64#define IS_UNICODE	BIT(0)
 65#define IS_BREAK	BIT(1)
 66#define IS_E0		BIT(2)
 67#define IS_E1		BIT(3)
 68struct synth_kbd_keystroke {
 69	struct synth_kbd_msg_hdr header;
 70	__le16 make_code;
 71	__le16 reserved0;
 72	__le32 info; /* Additional information */
 73};
 74
 75
 76#define HK_MAXIMUM_MESSAGE_SIZE 256
 77
 78#define KBD_VSC_SEND_RING_BUFFER_SIZE	VMBUS_RING_SIZE(36 * 1024)
 79#define KBD_VSC_RECV_RING_BUFFER_SIZE	VMBUS_RING_SIZE(36 * 1024)
 80
 81#define XTKBD_EMUL0     0xe0
 82#define XTKBD_EMUL1     0xe1
 83#define XTKBD_RELEASE   0x80
 84
 85
 86/*
 87 * Represents a keyboard device
 88 */
 89struct hv_kbd_dev {
 90	struct hv_device *hv_dev;
 91	struct serio *hv_serio;
 92	struct synth_kbd_protocol_request protocol_req;
 93	struct synth_kbd_protocol_response protocol_resp;
 94	/* Synchronize the request/response if needed */
 95	struct completion wait_event;
 96	spinlock_t lock; /* protects 'started' field */
 97	bool started;
 98};
 99
100static void hv_kbd_on_receive(struct hv_device *hv_dev,
101			      struct synth_kbd_msg *msg, u32 msg_length)
102{
103	struct hv_kbd_dev *kbd_dev = hv_get_drvdata(hv_dev);
104	struct synth_kbd_keystroke *ks_msg;
 
105	u32 msg_type = __le32_to_cpu(msg->header.type);
106	u32 info;
107	u16 scan_code;
108
109	switch (msg_type) {
110	case SYNTH_KBD_PROTOCOL_RESPONSE:
111		/*
112		 * Validate the information provided by the host.
113		 * If the host is giving us a bogus packet,
114		 * drop the packet (hoping the problem
115		 * goes away).
116		 */
117		if (msg_length < sizeof(struct synth_kbd_protocol_response)) {
118			dev_err(&hv_dev->device,
119				"Illegal protocol response packet (len: %d)\n",
120				msg_length);
121			break;
122		}
123
124		memcpy(&kbd_dev->protocol_resp, msg,
125			sizeof(struct synth_kbd_protocol_response));
126		complete(&kbd_dev->wait_event);
127		break;
128
129	case SYNTH_KBD_EVENT:
130		/*
131		 * Validate the information provided by the host.
132		 * If the host is giving us a bogus packet,
133		 * drop the packet (hoping the problem
134		 * goes away).
135		 */
136		if (msg_length < sizeof(struct  synth_kbd_keystroke)) {
137			dev_err(&hv_dev->device,
138				"Illegal keyboard event packet (len: %d)\n",
139				msg_length);
140			break;
141		}
142
143		ks_msg = (struct synth_kbd_keystroke *)msg;
144		info = __le32_to_cpu(ks_msg->info);
145
146		/*
147		 * Inject the information through the serio interrupt.
148		 */
149		scoped_guard(spinlock_irqsave, &kbd_dev->lock) {
150			if (kbd_dev->started) {
151				if (info & IS_E0)
152					serio_interrupt(kbd_dev->hv_serio,
153							XTKBD_EMUL0, 0);
154				if (info & IS_E1)
155					serio_interrupt(kbd_dev->hv_serio,
156							XTKBD_EMUL1, 0);
157				scan_code = __le16_to_cpu(ks_msg->make_code);
158				if (info & IS_BREAK)
159					scan_code |= XTKBD_RELEASE;
160
161				serio_interrupt(kbd_dev->hv_serio,
162						scan_code, 0);
163			}
164		}
 
165
166		/*
167		 * Only trigger a wakeup on key down, otherwise
168		 * "echo freeze > /sys/power/state" can't really enter the
169		 * state because the Enter-UP can trigger a wakeup at once.
170		 */
171		if (!(info & IS_BREAK))
172			pm_wakeup_hard_event(&hv_dev->device);
173
174		break;
175
176	default:
177		dev_err(&hv_dev->device,
178			"unhandled message type %d\n", msg_type);
179	}
180}
181
182static void hv_kbd_handle_received_packet(struct hv_device *hv_dev,
183					  struct vmpacket_descriptor *desc,
184					  u32 bytes_recvd,
185					  u64 req_id)
186{
187	struct synth_kbd_msg *msg;
188	u32 msg_sz;
189
190	switch (desc->type) {
191	case VM_PKT_COMP:
192		break;
193
194	case VM_PKT_DATA_INBAND:
195		/*
196		 * We have a packet that has "inband" data. The API used
197		 * for retrieving the packet guarantees that the complete
198		 * packet is read. So, minimally, we should be able to
199		 * parse the payload header safely (assuming that the host
200		 * can be trusted.  Trusting the host seems to be a
201		 * reasonable assumption because in a virtualized
202		 * environment there is not whole lot you can do if you
203		 * don't trust the host.
204		 *
205		 * Nonetheless, let us validate if the host can be trusted
206		 * (in a trivial way).  The interesting aspect of this
207		 * validation is how do you recover if we discover that the
208		 * host is not to be trusted? Simply dropping the packet, I
209		 * don't think is an appropriate recovery.  In the interest
210		 * of failing fast, it may be better to crash the guest.
211		 * For now, I will just drop the packet!
212		 */
213
214		msg_sz = bytes_recvd - (desc->offset8 << 3);
215		if (msg_sz <= sizeof(struct synth_kbd_msg_hdr)) {
216			/*
217			 * Drop the packet and hope
218			 * the problem magically goes away.
219			 */
220			dev_err(&hv_dev->device,
221				"Illegal packet (type: %d, tid: %llx, size: %d)\n",
222				desc->type, req_id, msg_sz);
223			break;
224		}
225
226		msg = (void *)desc + (desc->offset8 << 3);
227		hv_kbd_on_receive(hv_dev, msg, msg_sz);
228		break;
229
230	default:
231		dev_err(&hv_dev->device,
232			"unhandled packet type %d, tid %llx len %d\n",
233			desc->type, req_id, bytes_recvd);
234		break;
235	}
236}
237
238static void hv_kbd_on_channel_callback(void *context)
239{
240	struct vmpacket_descriptor *desc;
241	struct hv_device *hv_dev = context;
242	u32 bytes_recvd;
243	u64 req_id;
244
245	foreach_vmbus_pkt(desc, hv_dev->channel) {
246		bytes_recvd = desc->len8 * 8;
247		req_id = desc->trans_id;
248
249		hv_kbd_handle_received_packet(hv_dev, desc, bytes_recvd,
250					      req_id);
251	}
252}
253
254static int hv_kbd_connect_to_vsp(struct hv_device *hv_dev)
255{
256	struct hv_kbd_dev *kbd_dev = hv_get_drvdata(hv_dev);
257	struct synth_kbd_protocol_request *request;
258	struct synth_kbd_protocol_response *response;
259	u32 proto_status;
260	int error;
261
262	reinit_completion(&kbd_dev->wait_event);
263
264	request = &kbd_dev->protocol_req;
265	memset(request, 0, sizeof(struct synth_kbd_protocol_request));
266	request->header.type = __cpu_to_le32(SYNTH_KBD_PROTOCOL_REQUEST);
267	request->version_requested.version = __cpu_to_le32(SYNTH_KBD_VERSION);
268
269	error = vmbus_sendpacket(hv_dev->channel, request,
270				 sizeof(struct synth_kbd_protocol_request),
271				 (unsigned long)request,
272				 VM_PKT_DATA_INBAND,
273				 VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
274	if (error)
275		return error;
276
277	if (!wait_for_completion_timeout(&kbd_dev->wait_event, 10 * HZ))
278		return -ETIMEDOUT;
279
280	response = &kbd_dev->protocol_resp;
281	proto_status = __le32_to_cpu(response->proto_status);
282	if (!(proto_status & PROTOCOL_ACCEPTED)) {
283		dev_err(&hv_dev->device,
284			"synth_kbd protocol request failed (version %d)\n",
285		        SYNTH_KBD_VERSION);
286		return -ENODEV;
287	}
288
289	return 0;
290}
291
292static int hv_kbd_start(struct serio *serio)
293{
294	struct hv_kbd_dev *kbd_dev = serio->port_data;
 
295
296	guard(spinlock_irqsave)(&kbd_dev->lock);
297
298	kbd_dev->started = true;
 
299
300	return 0;
301}
302
303static void hv_kbd_stop(struct serio *serio)
304{
305	struct hv_kbd_dev *kbd_dev = serio->port_data;
 
306
307	guard(spinlock_irqsave)(&kbd_dev->lock);
308
309	kbd_dev->started = false;
 
310}
311
312static int hv_kbd_probe(struct hv_device *hv_dev,
313			const struct hv_vmbus_device_id *dev_id)
314{
315	struct hv_kbd_dev *kbd_dev;
316	struct serio *hv_serio;
317	int error;
318
319	kbd_dev = kzalloc(sizeof(*kbd_dev), GFP_KERNEL);
320	hv_serio = kzalloc(sizeof(*hv_serio), GFP_KERNEL);
321	if (!kbd_dev || !hv_serio) {
322		error = -ENOMEM;
323		goto err_free_mem;
324	}
325
326	kbd_dev->hv_dev = hv_dev;
327	kbd_dev->hv_serio = hv_serio;
328	spin_lock_init(&kbd_dev->lock);
329	init_completion(&kbd_dev->wait_event);
330	hv_set_drvdata(hv_dev, kbd_dev);
331
332	hv_serio->dev.parent  = &hv_dev->device;
333	hv_serio->id.type = SERIO_8042_XL;
334	hv_serio->port_data = kbd_dev;
335	strscpy(hv_serio->name, dev_name(&hv_dev->device),
336		sizeof(hv_serio->name));
337	strscpy(hv_serio->phys, dev_name(&hv_dev->device),
338		sizeof(hv_serio->phys));
339
340	hv_serio->start = hv_kbd_start;
341	hv_serio->stop = hv_kbd_stop;
342
343	error = vmbus_open(hv_dev->channel,
344			   KBD_VSC_SEND_RING_BUFFER_SIZE,
345			   KBD_VSC_RECV_RING_BUFFER_SIZE,
346			   NULL, 0,
347			   hv_kbd_on_channel_callback,
348			   hv_dev);
349	if (error)
350		goto err_free_mem;
351
352	error = hv_kbd_connect_to_vsp(hv_dev);
353	if (error)
354		goto err_close_vmbus;
355
356	serio_register_port(kbd_dev->hv_serio);
357
358	device_init_wakeup(&hv_dev->device, true);
359
360	return 0;
361
362err_close_vmbus:
363	vmbus_close(hv_dev->channel);
364err_free_mem:
365	kfree(hv_serio);
366	kfree(kbd_dev);
367	return error;
368}
369
370static void hv_kbd_remove(struct hv_device *hv_dev)
371{
372	struct hv_kbd_dev *kbd_dev = hv_get_drvdata(hv_dev);
373
374	serio_unregister_port(kbd_dev->hv_serio);
375	vmbus_close(hv_dev->channel);
376	kfree(kbd_dev);
377
378	hv_set_drvdata(hv_dev, NULL);
379}
380
381static int hv_kbd_suspend(struct hv_device *hv_dev)
382{
383	vmbus_close(hv_dev->channel);
384
385	return 0;
386}
387
388static int hv_kbd_resume(struct hv_device *hv_dev)
389{
390	int ret;
391
392	ret = vmbus_open(hv_dev->channel,
393			 KBD_VSC_SEND_RING_BUFFER_SIZE,
394			 KBD_VSC_RECV_RING_BUFFER_SIZE,
395			 NULL, 0,
396			 hv_kbd_on_channel_callback,
397			 hv_dev);
398	if (ret == 0)
399		ret = hv_kbd_connect_to_vsp(hv_dev);
400
401	return ret;
402}
403
404static const struct hv_vmbus_device_id id_table[] = {
405	/* Keyboard guid */
406	{ HV_KBD_GUID, },
407	{ },
408};
409
410MODULE_DEVICE_TABLE(vmbus, id_table);
411
412static struct  hv_driver hv_kbd_drv = {
413	.name = KBUILD_MODNAME,
414	.id_table = id_table,
415	.probe = hv_kbd_probe,
416	.remove = hv_kbd_remove,
417	.suspend = hv_kbd_suspend,
418	.resume = hv_kbd_resume,
419	.driver = {
420		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
421	},
422};
423
424static int __init hv_kbd_init(void)
425{
426	return vmbus_driver_register(&hv_kbd_drv);
427}
428
429static void __exit hv_kbd_exit(void)
430{
431	vmbus_driver_unregister(&hv_kbd_drv);
432}
433
434MODULE_LICENSE("GPL");
435MODULE_DESCRIPTION("Microsoft Hyper-V Synthetic Keyboard Driver");
436
437module_init(hv_kbd_init);
438module_exit(hv_kbd_exit);