xref: /netbsd-src/sys/external/bsd/vchiq/dist/interface/vchiq_arm/vchiq_arm.c (revision d909946ca08dceb44d7d0f22ec9488679695d976)
1 /**
2  * Copyright (c) 2010-2012 Broadcom. All rights reserved.
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that the following conditions
6  * are met:
7  * 1. Redistributions of source code must retain the above copyright
8  *    notice, this list of conditions, and the following disclaimer,
9  *    without modification.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. The names of the above-listed copyright holders may not be used
14  *    to endorse or promote products derived from this software without
15  *    specific prior written permission.
16  *
17  * ALTERNATIVELY, this software may be distributed under the terms of the
18  * GNU General Public License ("GPL") version 2, as published by the Free
19  * Software Foundation.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
22  * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
23  * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
24  * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
25  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
26  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
27  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
28  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
29  * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
30  * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
31  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32  */
33 
34 #include <sys/cdefs.h>
35 #include <sys/systm.h>
36 #include <sys/device.h>
37 #include <sys/file.h>
38 #include <sys/filedesc.h>
39 #include <sys/kmem.h>
40 
41 #include "vchiq_core.h"
42 #include "vchiq_ioctl.h"
43 #include "vchiq_arm.h"
44 
45 #define DEVICE_NAME "vchiq"
46 
47 /* Override the default prefix, which would be vchiq_arm (from the filename) */
48 #undef MODULE_PARAM_PREFIX
49 #define MODULE_PARAM_PREFIX DEVICE_NAME "."
50 
51 #define VCHIQ_MINOR 0
52 
53 /* Some per-instance constants */
54 #define MAX_COMPLETIONS 16
55 #define MAX_SERVICES 64
56 #define MAX_ELEMENTS 8
57 #define MSG_QUEUE_SIZE 64
58 
59 #define KEEPALIVE_VER 1
60 #define KEEPALIVE_VER_MIN KEEPALIVE_VER
61 
62 MALLOC_DEFINE(M_VCHIQ, "vchiq_cdev", "VideoCore cdev memory");
63 
64 /* Run time control of log level, based on KERN_XXX level. */
65 int vchiq_arm_log_level = VCHIQ_LOG_DEFAULT;
66 int vchiq_susp_log_level = VCHIQ_LOG_ERROR;
67 
68 #define SUSPEND_TIMER_TIMEOUT_MS 100
69 #define SUSPEND_RETRY_TIMER_TIMEOUT_MS 1000
70 
71 #define VC_SUSPEND_NUM_OFFSET 3 /* number of values before idle which are -ve */
72 static const char *const suspend_state_names[] = {
73 	"VC_SUSPEND_FORCE_CANCELED",
74 	"VC_SUSPEND_REJECTED",
75 	"VC_SUSPEND_FAILED",
76 	"VC_SUSPEND_IDLE",
77 	"VC_SUSPEND_REQUESTED",
78 	"VC_SUSPEND_IN_PROGRESS",
79 	"VC_SUSPEND_SUSPENDED"
80 };
81 #define VC_RESUME_NUM_OFFSET 1 /* number of values before idle which are -ve */
82 static const char *const resume_state_names[] = {
83 	"VC_RESUME_FAILED",
84 	"VC_RESUME_IDLE",
85 	"VC_RESUME_REQUESTED",
86 	"VC_RESUME_IN_PROGRESS",
87 	"VC_RESUME_RESUMED"
88 };
89 /* The number of times we allow force suspend to timeout before actually
90 ** _forcing_ suspend.  This is to cater for SW which fails to release vchiq
91 ** correctly - we don't want to prevent ARM suspend indefinitely in this case.
92 */
93 #define FORCE_SUSPEND_FAIL_MAX 8
94 
95 /* The time in ms allowed for videocore to go idle when force suspend has been
96  * requested */
97 #define FORCE_SUSPEND_TIMEOUT_MS 200
98 
99 
100 static void suspend_timer_callback(unsigned long context);
101 #ifdef notyet
102 static int vchiq_proc_add_instance(VCHIQ_INSTANCE_T instance);
103 static void vchiq_proc_remove_instance(VCHIQ_INSTANCE_T instance);
104 #endif
105 
106 
107 typedef struct user_service_struct {
108 	VCHIQ_SERVICE_T *service;
109 	void *userdata;
110 	VCHIQ_INSTANCE_T instance;
111 	int is_vchi;
112 	int dequeue_pending;
113 	int message_available_pos;
114 	int msg_insert;
115 	int msg_remove;
116 	struct semaphore insert_event;
117 	struct semaphore remove_event;
118 	VCHIQ_HEADER_T * msg_queue[MSG_QUEUE_SIZE];
119 } USER_SERVICE_T;
120 
121 struct bulk_waiter_node {
122 	struct bulk_waiter bulk_waiter;
123 	int pid;
124 	struct list_head list;
125 };
126 
127 struct vchiq_instance_struct {
128 	VCHIQ_STATE_T *state;
129 	VCHIQ_COMPLETION_DATA_T completions[MAX_COMPLETIONS];
130 	int completion_insert;
131 	int completion_remove;
132 	struct semaphore insert_event;
133 	struct semaphore remove_event;
134 	struct mutex completion_mutex;
135 
136 	int connected;
137 	int closing;
138 	int pid;
139 	int mark;
140 
141 	struct list_head bulk_waiter_list;
142 	struct mutex bulk_waiter_list_mutex;
143 
144 	struct proc_dir_entry *proc_entry;
145 };
146 
147 typedef struct dump_context_struct {
148 	char __user *buf;
149 	size_t actual;
150 	size_t space;
151 	loff_t offset;
152 } DUMP_CONTEXT_T;
153 
154 VCHIQ_STATE_T g_state;
155 static DEFINE_SPINLOCK(msg_queue_spinlock);
156 
157 static const char *const ioctl_names[] = {
158 	"CONNECT",
159 	"SHUTDOWN",
160 	"CREATE_SERVICE",
161 	"REMOVE_SERVICE",
162 	"QUEUE_MESSAGE",
163 	"QUEUE_BULK_TRANSMIT",
164 	"QUEUE_BULK_RECEIVE",
165 	"AWAIT_COMPLETION",
166 	"DEQUEUE_MESSAGE",
167 	"GET_CLIENT_ID",
168 	"GET_CONFIG",
169 	"CLOSE_SERVICE",
170 	"USE_SERVICE",
171 	"RELEASE_SERVICE",
172 	"SET_SERVICE_OPTION",
173 	"DUMP_PHYS_MEM"
174 };
175 
176 vchiq_static_assert((sizeof(ioctl_names)/sizeof(ioctl_names[0])) ==
177 	(VCHIQ_IOC_MAX + 1));
178 
179 static dev_type_open(vchiq_open);
180 
181 struct cdevsw vchiq_cdevsw = {
182 	.d_open = vchiq_open,
183 	.d_close = noclose,
184 	.d_read = noread,
185 	.d_write = nowrite,
186 	.d_ioctl = noioctl,
187 	.d_stop = nostop,
188 	.d_tty = notty,
189 	.d_poll = nopoll,
190 	.d_mmap = nommap,
191 	.d_kqfilter = nokqfilter,
192 	.d_discard = nodiscard,
193 	.d_flag = D_OTHER | D_MPSAFE
194 };
195 
196 extern struct cfdriver vchiq_cd;
197 
198 static int	vchiq_ioctl(struct file *, u_long, void *);
199 static int	vchiq_close(struct file *);
200 static int	vchiq_read(struct file *, off_t *, struct uio *, kauth_cred_t, int);
201 
202 static const struct fileops vchiq_fileops = {
203 	.fo_read = vchiq_read,
204 	.fo_write = fbadop_write,
205 	.fo_ioctl = vchiq_ioctl,
206 	.fo_fcntl = fnullop_fcntl,
207 	.fo_poll = fnullop_poll,
208 	.fo_stat = fbadop_stat,
209 	.fo_close = vchiq_close,
210 	.fo_kqfilter = fnullop_kqfilter,
211 };
212 
213 #if 0
214 static void
215 dump_phys_mem(void *virt_addr, uint32_t num_bytes);
216 #endif
217 
218 /****************************************************************************
219 *
220 *   add_completion
221 *
222 ***************************************************************************/
223 
224 static VCHIQ_STATUS_T
225 add_completion(VCHIQ_INSTANCE_T instance, VCHIQ_REASON_T reason,
226 	VCHIQ_HEADER_T *header, USER_SERVICE_T *user_service,
227 	void *bulk_userdata)
228 {
229 	VCHIQ_COMPLETION_DATA_T *completion;
230 	DEBUG_INITIALISE(g_state.local)
231 
232 	while (instance->completion_insert ==
233 		(instance->completion_remove + MAX_COMPLETIONS)) {
234 		/* Out of space - wait for the client */
235 		DEBUG_TRACE(SERVICE_CALLBACK_LINE);
236 		vchiq_log_trace(vchiq_arm_log_level,
237 			"add_completion - completion queue full");
238 		DEBUG_COUNT(COMPLETION_QUEUE_FULL_COUNT);
239 		if (down_interruptible(&instance->remove_event) != 0) {
240 			vchiq_log_info(vchiq_arm_log_level,
241 				"service_callback interrupted");
242 			return VCHIQ_RETRY;
243 		} else if (instance->closing) {
244 			vchiq_log_info(vchiq_arm_log_level,
245 				"service_callback closing");
246 			return VCHIQ_ERROR;
247 		}
248 		DEBUG_TRACE(SERVICE_CALLBACK_LINE);
249 	}
250 
251 	completion =
252 		 &instance->completions[instance->completion_insert &
253 		 (MAX_COMPLETIONS - 1)];
254 
255 	completion->header = header;
256 	completion->reason = reason;
257 	/* N.B. service_userdata is updated while processing AWAIT_COMPLETION */
258 	completion->service_userdata = user_service->service;
259 	completion->bulk_userdata = bulk_userdata;
260 
261 	if (reason == VCHIQ_SERVICE_CLOSED)
262 		/* Take an extra reference, to be held until
263 		   this CLOSED notification is delivered. */
264 		lock_service(user_service->service);
265 
266 	/* A write barrier is needed here to ensure that the entire completion
267 		record is written out before the insert point. */
268 	wmb();
269 
270 	if (reason == VCHIQ_MESSAGE_AVAILABLE)
271 		user_service->message_available_pos =
272 			instance->completion_insert;
273 	instance->completion_insert++;
274 
275 	up(&instance->insert_event);
276 
277 	return VCHIQ_SUCCESS;
278 }
279 
280 /****************************************************************************
281 *
282 *   service_callback
283 *
284 ***************************************************************************/
285 
286 static VCHIQ_STATUS_T
287 service_callback(VCHIQ_REASON_T reason, VCHIQ_HEADER_T *header,
288 	VCHIQ_SERVICE_HANDLE_T handle, void *bulk_userdata)
289 {
290 	/* How do we ensure the callback goes to the right client?
291 	** The service_user data points to a USER_SERVICE_T record containing
292 	** the original callback and the user state structure, which contains a
293 	** circular buffer for completion records.
294 	*/
295 	USER_SERVICE_T *user_service;
296 	VCHIQ_SERVICE_T *service;
297 	VCHIQ_INSTANCE_T instance;
298 	DEBUG_INITIALISE(g_state.local)
299 
300 	DEBUG_TRACE(SERVICE_CALLBACK_LINE);
301 
302 	service = handle_to_service(handle);
303 	BUG_ON(!service);
304 	user_service = (USER_SERVICE_T *)service->base.userdata;
305 	instance = user_service->instance;
306 
307 	if (!instance || instance->closing)
308 		return VCHIQ_SUCCESS;
309 
310 	vchiq_log_trace(vchiq_arm_log_level,
311 		"service_callback - service %lx(%d), handle %x, reason %d, header %lx, "
312 		"instance %lx, bulk_userdata %lx",
313 		(unsigned long)user_service,
314 		service->localport, service->handle,
315 		reason, (unsigned long)header,
316 		(unsigned long)instance, (unsigned long)bulk_userdata);
317 
318 	if (header && user_service->is_vchi) {
319 		spin_lock(&msg_queue_spinlock);
320 		while (user_service->msg_insert ==
321 			(user_service->msg_remove + MSG_QUEUE_SIZE)) {
322 			spin_unlock(&msg_queue_spinlock);
323 			DEBUG_TRACE(SERVICE_CALLBACK_LINE);
324 			DEBUG_COUNT(MSG_QUEUE_FULL_COUNT);
325 			vchiq_log_trace(vchiq_arm_log_level,
326 				"service_callback - msg queue full");
327 			/* If there is no MESSAGE_AVAILABLE in the completion
328 			** queue, add one
329 			*/
330 			if ((user_service->message_available_pos -
331 				instance->completion_remove) < 0) {
332 				VCHIQ_STATUS_T status;
333 				vchiq_log_info(vchiq_arm_log_level,
334 					"Inserting extra MESSAGE_AVAILABLE");
335 				DEBUG_TRACE(SERVICE_CALLBACK_LINE);
336 				status = add_completion(instance, reason,
337 					NULL, user_service, bulk_userdata);
338 				if (status != VCHIQ_SUCCESS) {
339 					DEBUG_TRACE(SERVICE_CALLBACK_LINE);
340 					return status;
341 				}
342 			}
343 
344 			DEBUG_TRACE(SERVICE_CALLBACK_LINE);
345 			if (down_interruptible(&user_service->remove_event)
346 				!= 0) {
347 				vchiq_log_info(vchiq_arm_log_level,
348 					"service_callback interrupted");
349 				DEBUG_TRACE(SERVICE_CALLBACK_LINE);
350 				return VCHIQ_RETRY;
351 			} else if (instance->closing) {
352 				vchiq_log_info(vchiq_arm_log_level,
353 					"service_callback closing");
354 				DEBUG_TRACE(SERVICE_CALLBACK_LINE);
355 				return VCHIQ_ERROR;
356 			}
357 			DEBUG_TRACE(SERVICE_CALLBACK_LINE);
358 			spin_lock(&msg_queue_spinlock);
359 		}
360 
361 		user_service->msg_queue[user_service->msg_insert &
362 			(MSG_QUEUE_SIZE - 1)] = header;
363 		user_service->msg_insert++;
364 		spin_unlock(&msg_queue_spinlock);
365 
366 		up(&user_service->insert_event);
367 
368 		/* If there is a thread waiting in DEQUEUE_MESSAGE, or if
369 		** there is a MESSAGE_AVAILABLE in the completion queue then
370 		** bypass the completion queue.
371 		*/
372 		if (((user_service->message_available_pos -
373 			instance->completion_remove) >= 0) ||
374 			user_service->dequeue_pending) {
375 			DEBUG_TRACE(SERVICE_CALLBACK_LINE);
376 			user_service->dequeue_pending = 0;
377 			return VCHIQ_SUCCESS;
378 		}
379 
380 		header = NULL;
381 	}
382 	DEBUG_TRACE(SERVICE_CALLBACK_LINE);
383 
384 	return add_completion(instance, reason, header, user_service,
385 		bulk_userdata);
386 }
387 
388 /****************************************************************************
389 *
390 *   user_service_free
391 *
392 ***************************************************************************/
393 static void
394 user_service_free(void *userdata)
395 {
396 	USER_SERVICE_T *user_service = userdata;
397 
398 	_sema_destroy(&user_service->insert_event);
399 	_sema_destroy(&user_service->remove_event);
400 
401 	kfree(user_service);
402 }
403 
404 /****************************************************************************
405 *
406 *   vchiq_ioctl
407 *
408 ***************************************************************************/
409 
410 static int
411 vchiq_ioctl(struct file *fp, u_long cmd, void *arg)
412 {
413 	VCHIQ_INSTANCE_T instance;
414 	VCHIQ_STATUS_T status = VCHIQ_SUCCESS;
415 	VCHIQ_SERVICE_T *service = NULL;
416 	int ret = 0;
417 	int i, rc;
418 	DEBUG_INITIALISE(g_state.local)
419 
420 	instance = fp->f_data;
421 
422 /* XXXBSD: HACK! */
423 #define _IOC_NR(x) ((x) & 0xff)
424 #define	_IOC_TYPE(x)	IOCGROUP(x)
425 
426 	vchiq_log_trace(vchiq_arm_log_level,
427 		 "vchiq_ioctl - instance %x, cmd %s, arg %p",
428 		(unsigned int)instance,
429 		((_IOC_TYPE(cmd) == VCHIQ_IOC_MAGIC) &&
430 		(_IOC_NR(cmd) <= VCHIQ_IOC_MAX)) ?
431 		ioctl_names[_IOC_NR(cmd)] : "<invalid>", arg);
432 
433 	switch (cmd) {
434 	case VCHIQ_IOC_SHUTDOWN:
435 		if (!instance->connected)
436 			break;
437 
438 		/* Remove all services */
439 		i = 0;
440 		while ((service = next_service_by_instance(instance->state,
441 			instance, &i)) != NULL) {
442 			status = vchiq_remove_service(service->handle);
443 			unlock_service(service);
444 			if (status != VCHIQ_SUCCESS)
445 				break;
446 		}
447 		service = NULL;
448 
449 		if (status == VCHIQ_SUCCESS) {
450 			/* Wake the completion thread and ask it to exit */
451 			instance->closing = 1;
452 			up(&instance->insert_event);
453 		}
454 
455 		break;
456 
457 	case VCHIQ_IOC_CONNECT:
458 		if (instance->connected) {
459 			ret = -EINVAL;
460 			break;
461 		}
462 		rc = lmutex_lock_interruptible(&instance->state->mutex);
463 		if (rc != 0) {
464 			vchiq_log_error(vchiq_arm_log_level,
465 				"vchiq: connect: could not lock mutex for "
466 				"state %d: %d",
467 				instance->state->id, rc);
468 			ret = -EINTR;
469 			break;
470 		}
471 		status = vchiq_connect_internal(instance->state, instance);
472 		lmutex_unlock(&instance->state->mutex);
473 
474 		if (status == VCHIQ_SUCCESS)
475 			instance->connected = 1;
476 		else
477 			vchiq_log_error(vchiq_arm_log_level,
478 				"vchiq: could not connect: %d", status);
479 		break;
480 
481 	case VCHIQ_IOC_CREATE_SERVICE: {
482 		VCHIQ_CREATE_SERVICE_T *pargs = arg;
483 		USER_SERVICE_T *user_service = NULL;
484 		void *userdata;
485 		int srvstate;
486 
487 		user_service = kzalloc(sizeof(USER_SERVICE_T), GFP_KERNEL);
488 		if (!user_service) {
489 			ret = -ENOMEM;
490 			break;
491 		}
492 
493 		if (pargs->is_open) {
494 			if (!instance->connected) {
495 				ret = -ENOTCONN;
496 				kfree(user_service);
497 				break;
498 			}
499 			srvstate = VCHIQ_SRVSTATE_OPENING;
500 		} else {
501 			srvstate =
502 				 instance->connected ?
503 				 VCHIQ_SRVSTATE_LISTENING :
504 				 VCHIQ_SRVSTATE_HIDDEN;
505 		}
506 
507 		userdata = pargs->params.userdata;
508 		pargs->params.callback = service_callback;
509 		pargs->params.userdata = user_service;
510 		service = vchiq_add_service_internal(
511 				instance->state,
512 				&pargs->params, srvstate,
513 				instance, user_service_free);
514 
515 		if (service != NULL) {
516 			user_service->service = service;
517 			user_service->userdata = userdata;
518 			user_service->instance = instance;
519 			user_service->is_vchi = pargs->is_vchi;
520 			user_service->dequeue_pending = 0;
521 			user_service->message_available_pos =
522 				instance->completion_remove - 1;
523 			user_service->msg_insert = 0;
524 			user_service->msg_remove = 0;
525 			_sema_init(&user_service->insert_event, 0);
526 			_sema_init(&user_service->remove_event, 0);
527 
528 			if (pargs->is_open) {
529 				status = vchiq_open_service_internal
530 					(service, instance->pid);
531 				if (status != VCHIQ_SUCCESS) {
532 					vchiq_remove_service(service->handle);
533 					service = NULL;
534 					ret = (status == VCHIQ_RETRY) ?
535 						-EINTR : -EIO;
536 					break;
537 				}
538 			}
539 
540 #ifdef VCHIQ_IOCTL_DEBUG
541 			printf("%s: [CREATE SERVICE] handle = %08x\n", __func__, service->handle);
542 #endif
543 			pargs->handle = service->handle;
544 
545 			service = NULL;
546 		} else {
547 			ret = -EEXIST;
548 			kfree(user_service);
549 		}
550 	} break;
551 
552 	case VCHIQ_IOC_CLOSE_SERVICE: {
553 		VCHIQ_SERVICE_HANDLE_T handle = *(VCHIQ_SERVICE_HANDLE_T *)arg;
554 
555 #ifdef VCHIQ_IOCTL_DEBUG
556 		printf("%s: [CLOSE SERVICE] handle = %08x\n", __func__, handle);
557 #endif
558 
559 		service = find_service_for_instance(instance, handle);
560 		if (service != NULL)
561 			status = vchiq_close_service(service->handle);
562 		else
563 			ret = -EINVAL;
564 	} break;
565 
566 	case VCHIQ_IOC_REMOVE_SERVICE: {
567 		VCHIQ_SERVICE_HANDLE_T handle = *(VCHIQ_SERVICE_HANDLE_T *)arg;
568 
569 #ifdef VCHIQ_IOCTL_DEBUG
570 		printf("%s: [REMOVE SERVICE] handle = %08x\n", __func__, handle);
571 #endif
572 
573 		service = find_service_for_instance(instance, handle);
574 		if (service != NULL)
575 			status = vchiq_remove_service(service->handle);
576 		else
577 			ret = -EINVAL;
578 	} break;
579 
580 	case VCHIQ_IOC_USE_SERVICE:
581 	case VCHIQ_IOC_RELEASE_SERVICE:	{
582 		VCHIQ_SERVICE_HANDLE_T handle = *(VCHIQ_SERVICE_HANDLE_T *)arg;
583 
584 #ifdef VCHIQ_IOCTL_DEBUG
585 		printf("%s: [%s SERVICE] handle = %08x\n", __func__,
586 		    cmd == VCHIQ_IOC_USE_SERVICE ? "USE" : "RELEASE", handle);
587 #endif
588 
589 		service = find_service_for_instance(instance, handle);
590 		if (service != NULL) {
591 			status = (cmd == VCHIQ_IOC_USE_SERVICE)	?
592 				vchiq_use_service_internal(service) :
593 				vchiq_release_service_internal(service);
594 			if (status != VCHIQ_SUCCESS) {
595 				vchiq_log_error(vchiq_susp_log_level,
596 					"%s: cmd %s returned error %d for "
597 					"service %c%c%c%c:%8x",
598 					__func__,
599 					(cmd == VCHIQ_IOC_USE_SERVICE) ?
600 						"VCHIQ_IOC_USE_SERVICE" :
601 						"VCHIQ_IOC_RELEASE_SERVICE",
602 					status,
603 					VCHIQ_FOURCC_AS_4CHARS(
604 						service->base.fourcc),
605 					service->client_id);
606 				ret = -EINVAL;
607 			}
608 		} else
609 			ret = -EINVAL;
610 	} break;
611 
612 	case VCHIQ_IOC_QUEUE_MESSAGE: {
613 		VCHIQ_QUEUE_MESSAGE_T *pargs = arg;
614 
615 #ifdef VCHIQ_IOCTL_DEBUG
616 		printf("%s: [QUEUE MESSAGE] handle = %08x\n", __func__, pargs->handle);
617 #endif
618 
619 		service = find_service_for_instance(instance, pargs->handle);
620 
621 		if ((service != NULL) && (pargs->count <= MAX_ELEMENTS)) {
622 			/* Copy elements into kernel space */
623 			VCHIQ_ELEMENT_T elements[MAX_ELEMENTS];
624 			if (copy_from_user(elements, pargs->elements,
625 				pargs->count * sizeof(VCHIQ_ELEMENT_T)) == 0)
626 				status = vchiq_queue_message
627 					(pargs->handle,
628 					elements, pargs->count);
629 			else
630 				ret = -EFAULT;
631 		} else {
632 			ret = -EINVAL;
633 		}
634 	} break;
635 
636 	case VCHIQ_IOC_QUEUE_BULK_TRANSMIT:
637 	case VCHIQ_IOC_QUEUE_BULK_RECEIVE: {
638 		VCHIQ_QUEUE_BULK_TRANSFER_T *pargs = arg;
639 		struct bulk_waiter_node *waiter = NULL;
640 		VCHIQ_BULK_DIR_T dir =
641 			(cmd == VCHIQ_IOC_QUEUE_BULK_TRANSMIT) ?
642 			VCHIQ_BULK_TRANSMIT : VCHIQ_BULK_RECEIVE;
643 
644 		service = find_service_for_instance(instance, pargs->handle);
645 		if (!service) {
646 			ret = -EINVAL;
647 			break;
648 		}
649 
650 		if (pargs->mode == VCHIQ_BULK_MODE_BLOCKING) {
651 			waiter = kzalloc(sizeof(struct bulk_waiter_node),
652 				GFP_KERNEL);
653 			if (!waiter) {
654 				ret = -ENOMEM;
655 				break;
656 			}
657 			pargs->userdata = &waiter->bulk_waiter;
658 		} else if (pargs->mode == VCHIQ_BULK_MODE_WAITING) {
659 			struct list_head *pos;
660 			lmutex_lock(&instance->bulk_waiter_list_mutex);
661 			list_for_each(pos, &instance->bulk_waiter_list) {
662 				if (list_entry(pos, struct bulk_waiter_node,
663 					list)->pid == current->l_proc->p_pid) {
664 					waiter = list_entry(pos,
665 						struct bulk_waiter_node,
666 						list);
667 					list_del(pos);
668 					break;
669 				}
670 
671 			}
672 			lmutex_unlock(&instance->bulk_waiter_list_mutex);
673 			if (!waiter) {
674 				vchiq_log_error(vchiq_arm_log_level,
675 					"no bulk_waiter found for pid %d",
676 					current->l_proc->p_pid);
677 				ret = -ESRCH;
678 				break;
679 			}
680 			vchiq_log_info(vchiq_arm_log_level,
681 				"found bulk_waiter %x for pid %d",
682 				(unsigned int)waiter, current->l_proc->p_pid);
683 			pargs->userdata = &waiter->bulk_waiter;
684 		}
685 		status = vchiq_bulk_transfer
686 			(pargs->handle,
687 			 VCHI_MEM_HANDLE_INVALID,
688 			 pargs->data, pargs->size,
689 			 pargs->userdata, pargs->mode,
690 			 dir);
691 		if (!waiter)
692 			break;
693 		if ((status != VCHIQ_RETRY) || fatal_signal_pending(current) ||
694 			!waiter->bulk_waiter.bulk) {
695 			if (waiter->bulk_waiter.bulk) {
696 				/* Cancel the signal when the transfer
697 				** completes. */
698 				spin_lock(&bulk_waiter_spinlock);
699 				waiter->bulk_waiter.bulk->userdata = NULL;
700 				spin_unlock(&bulk_waiter_spinlock);
701 			}
702 			_sema_destroy(&waiter->bulk_waiter.event);
703 			kfree(waiter);
704 		} else {
705 			const VCHIQ_BULK_MODE_T mode_waiting =
706 				VCHIQ_BULK_MODE_WAITING;
707 			waiter->pid = current->l_proc->p_pid;
708 			lmutex_lock(&instance->bulk_waiter_list_mutex);
709 			list_add(&waiter->list, &instance->bulk_waiter_list);
710 			lmutex_unlock(&instance->bulk_waiter_list_mutex);
711 			vchiq_log_info(vchiq_arm_log_level,
712 				"saved bulk_waiter %x for pid %d",
713 				(unsigned int)waiter, current->l_proc->p_pid);
714 
715 			pargs->mode = mode_waiting;
716 		}
717 	} break;
718 
719 	case VCHIQ_IOC_AWAIT_COMPLETION: {
720 		VCHIQ_AWAIT_COMPLETION_T *pargs = arg;
721 		int count = 0;
722 
723 		DEBUG_TRACE(AWAIT_COMPLETION_LINE);
724 		if (!instance->connected) {
725 			ret = -ENOTCONN;
726 			break;
727 		}
728 
729 		lmutex_lock(&instance->completion_mutex);
730 
731 		DEBUG_TRACE(AWAIT_COMPLETION_LINE);
732 		while ((instance->completion_remove ==
733 			instance->completion_insert)
734 			&& !instance->closing) {
735 			DEBUG_TRACE(AWAIT_COMPLETION_LINE);
736 			lmutex_unlock(&instance->completion_mutex);
737 			rc = down_interruptible(&instance->insert_event);
738 			lmutex_lock(&instance->completion_mutex);
739 			if (rc != 0) {
740 				DEBUG_TRACE(AWAIT_COMPLETION_LINE);
741 				vchiq_log_info(vchiq_arm_log_level,
742 					"AWAIT_COMPLETION interrupted");
743 				ret = -EINTR;
744 				break;
745 			}
746 		}
747 		DEBUG_TRACE(AWAIT_COMPLETION_LINE);
748 
749 		/* A read memory barrier is needed to stop prefetch of a stale
750 		** completion record
751 		*/
752 		rmb();
753 
754 		if (ret == 0) {
755 			int msgbufcount = pargs->msgbufcount;
756 
757 			for (; count < pargs->count; count++) {
758 				VCHIQ_COMPLETION_DATA_T *completion;
759 				VCHIQ_SERVICE_T *service1;
760 				USER_SERVICE_T *user_service;
761 				VCHIQ_HEADER_T *header;
762 				if (instance->completion_remove ==
763 					instance->completion_insert)
764 					break;
765 				completion = &instance->completions[
766 					instance->completion_remove &
767 					(MAX_COMPLETIONS - 1)];
768 
769 				service1 = completion->service_userdata;
770 				user_service = service1->base.userdata;
771 				completion->service_userdata =
772 					user_service->userdata;
773 
774 				header = completion->header;
775 				if (header) {
776 					void __user *msgbuf;
777 					int msglen;
778 
779 					msglen = header->size +
780 						sizeof(VCHIQ_HEADER_T);
781 					/* This must be a VCHIQ-style service */
782 					if (pargs->msgbufsize < msglen) {
783 						vchiq_log_error(
784 							vchiq_arm_log_level,
785 							"header %x: msgbufsize"
786 							" %x < msglen %x",
787 							(unsigned int)header,
788 							pargs->msgbufsize,
789 							msglen);
790 						WARN(1, "invalid message "
791 							"size\n");
792 						if (count == 0)
793 							ret = -EMSGSIZE;
794 						break;
795 					}
796 					if (msgbufcount <= 0)
797 						/* Stall here for lack of a
798 						** buffer for the message. */
799 						break;
800 					/* Get the pointer from user space */
801 					msgbufcount--;
802 					if (copy_from_user(&msgbuf,
803 						(const void __user *)
804 						&pargs->msgbufs[msgbufcount],
805 						sizeof(msgbuf)) != 0) {
806 						if (count == 0)
807 							ret = -EFAULT;
808 						break;
809 					}
810 
811 					/* Copy the message to user space */
812 					if (copy_to_user(msgbuf, header,
813 						msglen) != 0) {
814 						if (count == 0)
815 							ret = -EFAULT;
816 						break;
817 					}
818 
819 					/* Now it has been copied, the message
820 					** can be released. */
821 					vchiq_release_message(service1->handle,
822 						header);
823 
824 					/* The completion must point to the
825 					** msgbuf. */
826 					completion->header = msgbuf;
827 				}
828 
829 				if (completion->reason ==
830 					VCHIQ_SERVICE_CLOSED)
831 					unlock_service(service1);
832 
833 				if (copy_to_user((void __user *)(
834 					(size_t)pargs->buf +
835 					count * sizeof(VCHIQ_COMPLETION_DATA_T)),
836 					completion,
837 					sizeof(VCHIQ_COMPLETION_DATA_T)) != 0) {
838 						if (count == 0)
839 							ret = -EFAULT;
840 					break;
841 				}
842 
843 				instance->completion_remove++;
844 			}
845 
846 			pargs->msgbufcount = msgbufcount;
847 			pargs->count = count;
848 		}
849 
850 		if (count != 0)
851 			up(&instance->remove_event);
852 		lmutex_unlock(&instance->completion_mutex);
853 		DEBUG_TRACE(AWAIT_COMPLETION_LINE);
854 	} break;
855 
856 	case VCHIQ_IOC_DEQUEUE_MESSAGE: {
857 		VCHIQ_DEQUEUE_MESSAGE_T *pargs = arg;
858 		USER_SERVICE_T *user_service;
859 		VCHIQ_HEADER_T *header;
860 
861 		DEBUG_TRACE(DEQUEUE_MESSAGE_LINE);
862 		service = find_service_for_instance(instance, pargs->handle);
863 		if (!service) {
864 			ret = -EINVAL;
865 			break;
866 		}
867 		user_service = (USER_SERVICE_T *)service->base.userdata;
868 		if (user_service->is_vchi == 0) {
869 			ret = -EINVAL;
870 			break;
871 		}
872 
873 		spin_lock(&msg_queue_spinlock);
874 		if (user_service->msg_remove == user_service->msg_insert) {
875 			if (!pargs->blocking) {
876 				spin_unlock(&msg_queue_spinlock);
877 				DEBUG_TRACE(DEQUEUE_MESSAGE_LINE);
878 				ret = -EWOULDBLOCK;
879 				break;
880 			}
881 			user_service->dequeue_pending = 1;
882 			do {
883 				spin_unlock(&msg_queue_spinlock);
884 				DEBUG_TRACE(DEQUEUE_MESSAGE_LINE);
885 				if (down_interruptible(
886 					&user_service->insert_event) != 0) {
887 					vchiq_log_info(vchiq_arm_log_level,
888 						"DEQUEUE_MESSAGE interrupted");
889 					ret = -EINTR;
890 					break;
891 				}
892 				spin_lock(&msg_queue_spinlock);
893 			} while (user_service->msg_remove ==
894 				user_service->msg_insert);
895 
896 			if (ret)
897 				break;
898 		}
899 
900 		BUG_ON((int)(user_service->msg_insert -
901 			user_service->msg_remove) < 0);
902 
903 		header = user_service->msg_queue[user_service->msg_remove &
904 			(MSG_QUEUE_SIZE - 1)];
905 		user_service->msg_remove++;
906 		spin_unlock(&msg_queue_spinlock);
907 
908 		up(&user_service->remove_event);
909 		if (header == NULL)
910 			ret = -ENOTCONN;
911 		else if (header->size <= pargs->bufsize) {
912 			/* Copy to user space if msgbuf is not NULL */
913 			if ((pargs->buf == NULL) ||
914 				(copy_to_user((void __user *)pargs->buf,
915 				header->data,
916 				header->size) == 0)) {
917 				pargs->bufsize = header->size;
918 				vchiq_release_message(
919 					service->handle,
920 					header);
921 			} else
922 				ret = -EFAULT;
923 		} else {
924 			vchiq_log_error(vchiq_arm_log_level,
925 				"header %x: bufsize %x < size %x",
926 				(unsigned int)header, pargs->bufsize,
927 				header->size);
928 			WARN(1, "invalid size\n");
929 			ret = -EMSGSIZE;
930 		}
931 		DEBUG_TRACE(DEQUEUE_MESSAGE_LINE);
932 	} break;
933 
934 	case VCHIQ_IOC_GET_CLIENT_ID: {
935 		VCHIQ_SERVICE_HANDLE_T handle = (VCHIQ_SERVICE_HANDLE_T)arg;
936 
937 		ret = vchiq_get_client_id(handle);
938 	} break;
939 
940 	case VCHIQ_IOC_GET_CONFIG: {
941 		VCHIQ_GET_CONFIG_T *pargs = arg;
942 		VCHIQ_CONFIG_T config;
943 
944 		if (pargs->config_size > sizeof(config)) {
945 			ret = -EINVAL;
946 			break;
947 		}
948 		status = vchiq_get_config(instance, pargs->config_size, &config);
949 		if (status == VCHIQ_SUCCESS) {
950 			if (copy_to_user((void __user *)pargs->pconfig,
951 				&config, pargs->config_size) != 0) {
952 				ret = -EFAULT;
953 				break;
954 			}
955 		}
956 	} break;
957 
958 	case VCHIQ_IOC_SET_SERVICE_OPTION: {
959 		VCHIQ_SET_SERVICE_OPTION_T *pargs = arg;
960 
961 		service = find_service_for_instance(instance, pargs->handle);
962 		if (!service) {
963 			ret = -EINVAL;
964 			break;
965 		}
966 
967 		status = vchiq_set_service_option(
968 				pargs->handle, pargs->option, pargs->value);
969 	} break;
970 
971 	case VCHIQ_IOC_DUMP_PHYS_MEM: {
972 #if 0
973 		VCHIQ_DUMP_MEM_T *pargs = arg;
974 #endif
975 
976 		printf("IMPLEMENT ME: %s:%d\n", __FILE__, __LINE__);
977 #if 0
978 		dump_phys_mem(pargs->virt_addr, pargs->num_bytes);
979 #endif
980 	} break;
981 
982 	default:
983 		ret = -ENOTTY;
984 		break;
985 	}
986 
987 	if (service)
988 		unlock_service(service);
989 
990 	if (ret == 0) {
991 		if (status == VCHIQ_ERROR)
992 			ret = -EIO;
993 		else if (status == VCHIQ_RETRY)
994 			ret = -EINTR;
995 	}
996 
997 	if ((status == VCHIQ_SUCCESS) && (ret < 0) && (ret != -EINTR) &&
998 		(ret != -EWOULDBLOCK))
999 		vchiq_log_info(vchiq_arm_log_level,
1000 			"  ioctl instance %lx, cmd %s -> status %d, %d",
1001 			(unsigned long)instance,
1002 			(_IOC_NR(cmd) <= VCHIQ_IOC_MAX) ?
1003 				ioctl_names[_IOC_NR(cmd)] :
1004 				"<invalid>",
1005 			status, ret);
1006 	else
1007 		vchiq_log_trace(vchiq_arm_log_level,
1008 			"  ioctl instance %lx, cmd %s -> status %d, %d",
1009 			(unsigned long)instance,
1010 			(_IOC_NR(cmd) <= VCHIQ_IOC_MAX) ?
1011 				ioctl_names[_IOC_NR(cmd)] :
1012 				"<invalid>",
1013 			status, ret);
1014 
1015 	/* XXXBSD: report BSD-style error to userland */
1016 	if (ret < 0)
1017 		ret = -ret;
1018 
1019 	return ret;
1020 }
1021 
1022 #if notyet
1023 static void
1024 instance_dtr(void *data)
1025 {
1026 
1027    free(data, M_VCHIQ);
1028 }
1029 #endif
1030 
1031 /****************************************************************************
1032 *
1033 *   vchiq_open
1034 *
1035 ***************************************************************************/
1036 
1037 static int
1038 vchiq_open(dev_t dev, int flags, int mode, lwp_t *l)
1039 {
1040 	VCHIQ_INSTANCE_T instance = NULL;
1041 	struct file *fp;
1042 	int err, fd;
1043 
1044 	vchiq_log_info(vchiq_arm_log_level, "vchiq_open");
1045 
1046 	/* XXXBSD: do we really need this check? */
1047 	if (device_lookup_private(&vchiq_cd, minor(dev)) != NULL) {
1048 		VCHIQ_STATE_T *state = vchiq_get_state();
1049 
1050 		if (!state) {
1051 			vchiq_log_error(vchiq_arm_log_level,
1052 				"vchiq has no connection to VideoCore");
1053 			return -ENOTCONN;
1054 		}
1055 
1056 		instance = kzalloc(sizeof(*instance), GFP_KERNEL);
1057 		if (!instance)
1058 			return -ENOMEM;
1059 
1060 		err = fd_allocfile(&fp, &fd);
1061 		if (err) {
1062 			kfree(instance);
1063 			return -err;
1064 		}
1065 
1066 		instance->state = state;
1067 		instance->pid = current->l_proc->p_pid;
1068 
1069 #ifdef notyet
1070 		ret = vchiq_proc_add_instance(instance);
1071 		if (ret != 0) {
1072 			kfree(instance);
1073 			return ret;
1074 		}
1075 #endif
1076 
1077 		_sema_init(&instance->insert_event, 0);
1078 		_sema_init(&instance->remove_event, 0);
1079 		lmutex_init(&instance->completion_mutex);
1080 		lmutex_init(&instance->bulk_waiter_list_mutex);
1081 		INIT_LIST_HEAD(&instance->bulk_waiter_list);
1082 
1083 	}
1084 	else {
1085 		vchiq_log_error(vchiq_arm_log_level,
1086 			"Unknown minor device");
1087 		return -ENXIO;
1088 	}
1089 
1090 	return fd_clone(fp, fd, flags, &vchiq_fileops, instance);
1091 }
1092 
1093 /****************************************************************************
1094 *
1095 *   vchiq_release
1096 *
1097 ***************************************************************************/
1098 
1099 static int
1100 vchiq_close(struct file *fp)
1101 {
1102 	int ret = 0;
1103 	if (1) {
1104 		VCHIQ_INSTANCE_T instance;
1105 		VCHIQ_STATE_T *state = vchiq_get_state();
1106 		VCHIQ_SERVICE_T *service;
1107 		int i;
1108 
1109 		instance = fp->f_data;
1110 
1111 		vchiq_log_info(vchiq_arm_log_level,
1112 			"vchiq_release: instance=%lx",
1113 			(unsigned long)instance);
1114 
1115 		if (!state) {
1116 			ret = -EPERM;
1117 			goto out;
1118 		}
1119 
1120 		/* Ensure videocore is awake to allow termination. */
1121 		vchiq_use_internal(instance->state, NULL,
1122 				USE_TYPE_VCHIQ);
1123 
1124 		lmutex_lock(&instance->completion_mutex);
1125 
1126 		/* Wake the completion thread and ask it to exit */
1127 		instance->closing = 1;
1128 		up(&instance->insert_event);
1129 
1130 		lmutex_unlock(&instance->completion_mutex);
1131 
1132 		/* Wake the slot handler if the completion queue is full. */
1133 		up(&instance->remove_event);
1134 
1135 		/* Mark all services for termination... */
1136 		i = 0;
1137 		while ((service = next_service_by_instance(state, instance,
1138 			&i)) !=	NULL) {
1139 			USER_SERVICE_T *user_service = service->base.userdata;
1140 
1141 			/* Wake the slot handler if the msg queue is full. */
1142 			up(&user_service->remove_event);
1143 
1144 			vchiq_terminate_service_internal(service);
1145 			unlock_service(service);
1146 		}
1147 
1148 		/* ...and wait for them to die */
1149 		i = 0;
1150 		while ((service = next_service_by_instance(state, instance, &i))
1151 			!= NULL) {
1152 			USER_SERVICE_T *user_service = service->base.userdata;
1153 
1154 			down(&service->remove_event);
1155 
1156 			BUG_ON(service->srvstate != VCHIQ_SRVSTATE_FREE);
1157 
1158 			spin_lock(&msg_queue_spinlock);
1159 
1160 			while (user_service->msg_remove !=
1161 				user_service->msg_insert) {
1162 				VCHIQ_HEADER_T *header = user_service->
1163 					msg_queue[user_service->msg_remove &
1164 						(MSG_QUEUE_SIZE - 1)];
1165 				user_service->msg_remove++;
1166 				spin_unlock(&msg_queue_spinlock);
1167 
1168 				if (header)
1169 					vchiq_release_message(
1170 						service->handle,
1171 						header);
1172 				spin_lock(&msg_queue_spinlock);
1173 			}
1174 
1175 			spin_unlock(&msg_queue_spinlock);
1176 
1177 			unlock_service(service);
1178 		}
1179 
1180 		/* Release any closed services */
1181 		while (instance->completion_remove !=
1182 			instance->completion_insert) {
1183 			VCHIQ_COMPLETION_DATA_T *completion;
1184 			VCHIQ_SERVICE_T *service1;
1185 			completion = &instance->completions[
1186 				instance->completion_remove &
1187 				(MAX_COMPLETIONS - 1)];
1188 			service1 = completion->service_userdata;
1189 			if (completion->reason == VCHIQ_SERVICE_CLOSED)
1190 				unlock_service(service1);
1191 			instance->completion_remove++;
1192 		}
1193 
1194 		/* Release the PEER service count. */
1195 		vchiq_release_internal(instance->state, NULL);
1196 
1197 		{
1198 			struct list_head *pos, *next;
1199 			list_for_each_safe(pos, next,
1200 				&instance->bulk_waiter_list) {
1201 				struct bulk_waiter_node *waiter;
1202 				waiter = list_entry(pos,
1203 					struct bulk_waiter_node,
1204 					list);
1205 				list_del(pos);
1206 				vchiq_log_info(vchiq_arm_log_level,
1207 					"bulk_waiter - cleaned up %x "
1208 					"for pid %d",
1209 					(unsigned int)waiter, waiter->pid);
1210 		                _sema_destroy(&waiter->bulk_waiter.event);
1211 				kfree(waiter);
1212 			}
1213 		}
1214 
1215 	}
1216 	else {
1217 		vchiq_log_error(vchiq_arm_log_level,
1218 			"Unknown minor device");
1219 		ret = -ENXIO;
1220 	}
1221 
1222 out:
1223 	return ret;
1224 }
1225 
1226 /****************************************************************************
1227 *
1228 *   vchiq_dump
1229 *
1230 ***************************************************************************/
1231 
1232 void
1233 vchiq_dump(void *dump_context, const char *str, int len)
1234 {
1235 	DUMP_CONTEXT_T *context = (DUMP_CONTEXT_T *)dump_context;
1236 
1237 	if (context->actual < context->space) {
1238 		int copy_bytes;
1239 		if (context->offset > 0) {
1240 			int skip_bytes = min(len, (int)context->offset);
1241 			str += skip_bytes;
1242 			len -= skip_bytes;
1243 			context->offset -= skip_bytes;
1244 			if (context->offset > 0)
1245 				return;
1246 		}
1247 		copy_bytes = min(len, (int)(context->space - context->actual));
1248 		if (copy_bytes == 0)
1249 			return;
1250 		memcpy(context->buf + context->actual, str, copy_bytes);
1251 		context->actual += copy_bytes;
1252 		len -= copy_bytes;
1253 
1254 		/* If tne terminating NUL is included in the length, then it
1255 		** marks the end of a line and should be replaced with a
1256 		** carriage return. */
1257 		if ((len == 0) && (str[copy_bytes - 1] == '\0')) {
1258 			char cr = '\n';
1259 			memcpy(context->buf + context->actual - 1, &cr, 1);
1260 		}
1261 	}
1262 }
1263 
1264 /****************************************************************************
1265 *
1266 *   vchiq_dump_platform_instance_state
1267 *
1268 ***************************************************************************/
1269 
1270 void
1271 vchiq_dump_platform_instances(void *dump_context)
1272 {
1273 	VCHIQ_STATE_T *state = vchiq_get_state();
1274 	char buf[80];
1275 	int len;
1276 	int i;
1277 
1278 	/* There is no list of instances, so instead scan all services,
1279 		marking those that have been dumped. */
1280 
1281 	for (i = 0; i < state->unused_service; i++) {
1282 		VCHIQ_SERVICE_T *service = state->services[i];
1283 		VCHIQ_INSTANCE_T instance;
1284 
1285 		if (service && (service->base.callback == service_callback)) {
1286 			instance = service->instance;
1287 			if (instance)
1288 				instance->mark = 0;
1289 		}
1290 	}
1291 
1292 	for (i = 0; i < state->unused_service; i++) {
1293 		VCHIQ_SERVICE_T *service = state->services[i];
1294 		VCHIQ_INSTANCE_T instance;
1295 
1296 		if (service && (service->base.callback == service_callback)) {
1297 			instance = service->instance;
1298 			if (instance && !instance->mark) {
1299 				len = snprintf(buf, sizeof(buf),
1300 					"Instance %x: pid %d,%s completions "
1301 						"%d/%d",
1302 					(unsigned int)instance, instance->pid,
1303 					instance->connected ? " connected, " :
1304 						"",
1305 					instance->completion_insert -
1306 						instance->completion_remove,
1307 					MAX_COMPLETIONS);
1308 
1309 				vchiq_dump(dump_context, buf, len + 1);
1310 
1311 				instance->mark = 1;
1312 			}
1313 		}
1314 	}
1315 }
1316 
1317 /****************************************************************************
1318 *
1319 *   vchiq_dump_platform_service_state
1320 *
1321 ***************************************************************************/
1322 
1323 void
1324 vchiq_dump_platform_service_state(void *dump_context, VCHIQ_SERVICE_T *service)
1325 {
1326 	USER_SERVICE_T *user_service = (USER_SERVICE_T *)service->base.userdata;
1327 	char buf[80];
1328 	int len;
1329 
1330 	len = snprintf(buf, sizeof(buf), "  instance %x",
1331 		(unsigned int)service->instance);
1332 
1333 	if ((service->base.callback == service_callback) &&
1334 		user_service->is_vchi) {
1335 		len += snprintf(buf + len, sizeof(buf) - len,
1336 			", %d/%d messages",
1337 			user_service->msg_insert - user_service->msg_remove,
1338 			MSG_QUEUE_SIZE);
1339 
1340 		if (user_service->dequeue_pending)
1341 			len += snprintf(buf + len, sizeof(buf) - len,
1342 				" (dequeue pending)");
1343 	}
1344 
1345 	vchiq_dump(dump_context, buf, len + 1);
1346 }
1347 
1348 #ifdef notyet
1349 /****************************************************************************
1350 *
1351 *   dump_user_mem
1352 *
1353 ***************************************************************************/
1354 
1355 static void
1356 dump_phys_mem(void *virt_addr, uint32_t num_bytes)
1357 {
1358 	int            rc;
1359 	uint8_t       *end_virt_addr = virt_addr + num_bytes;
1360 	int            num_pages;
1361 	int            offset;
1362 	int            end_offset;
1363 	int            page_idx;
1364 	int            prev_idx;
1365 	struct page   *page;
1366 	struct page  **pages;
1367 	uint8_t       *kmapped_virt_ptr;
1368 
1369 	/* Align virtAddr and endVirtAddr to 16 byte boundaries. */
1370 
1371 	virt_addr = (void *)((unsigned long)virt_addr & ~0x0fuL);
1372 	end_virt_addr = (void *)(((unsigned long)end_virt_addr + 15uL) &
1373 		~0x0fuL);
1374 
1375 	offset = (int)(long)virt_addr & (PAGE_SIZE - 1);
1376 	end_offset = (int)(long)end_virt_addr & (PAGE_SIZE - 1);
1377 
1378 	num_pages = (offset + num_bytes + PAGE_SIZE - 1) / PAGE_SIZE;
1379 
1380 	pages = kmalloc(sizeof(struct page *) * num_pages, GFP_KERNEL);
1381 	if (pages == NULL) {
1382 		vchiq_log_error(vchiq_arm_log_level,
1383 			"Unable to allocation memory for %d pages\n",
1384 			num_pages);
1385 		return;
1386 	}
1387 
1388 	down_read(&current->mm->mmap_sem);
1389 	rc = get_user_pages(current,      /* task */
1390 		current->mm,              /* mm */
1391 		(unsigned long)virt_addr, /* start */
1392 		num_pages,                /* len */
1393 		0,                        /* write */
1394 		0,                        /* force */
1395 		pages,                    /* pages (array of page pointers) */
1396 		NULL);                    /* vmas */
1397 	up_read(&current->mm->mmap_sem);
1398 
1399 	prev_idx = -1;
1400 	page = NULL;
1401 
1402 	while (offset < end_offset) {
1403 
1404 		int page_offset = offset % PAGE_SIZE;
1405 		page_idx = offset / PAGE_SIZE;
1406 
1407 		if (page_idx != prev_idx) {
1408 
1409 			if (page != NULL)
1410 				kunmap(page);
1411 			page = pages[page_idx];
1412 			kmapped_virt_ptr = kmap(page);
1413 
1414 			prev_idx = page_idx;
1415 		}
1416 
1417 		if (vchiq_arm_log_level >= VCHIQ_LOG_TRACE)
1418 			vchiq_log_dump_mem("ph",
1419 				(uint32_t)(unsigned long)&kmapped_virt_ptr[
1420 					page_offset],
1421 				&kmapped_virt_ptr[page_offset], 16);
1422 
1423 		offset += 16;
1424 	}
1425 	if (page != NULL)
1426 		kunmap(page);
1427 
1428 	for (page_idx = 0; page_idx < num_pages; page_idx++)
1429 		page_cache_release(pages[page_idx]);
1430 
1431 	kfree(pages);
1432 }
1433 #endif
1434 
1435 /****************************************************************************
1436 *
1437 *   vchiq_read
1438 *
1439 ***************************************************************************/
1440 
1441 static int
1442 vchiq_read(struct file *file, off_t *ppos, struct uio *uio, kauth_cred_t cred,
1443     int flags)
1444 {
1445 	int result;
1446 
1447 	char *buf = kmem_zalloc(PAGE_SIZE, KM_SLEEP);
1448 
1449 	DUMP_CONTEXT_T context;
1450 	context.buf = buf;
1451 	context.actual = 0;
1452 	context.space = PAGE_SIZE;
1453 	context.offset = *ppos;
1454 
1455 	vchiq_dump_state(&context, &g_state);
1456 
1457 	*ppos += context.actual;
1458 
1459 	result = uiomove(buf, context.actual, uio);
1460 	kmem_free(buf, PAGE_SIZE);
1461 
1462 	return result;
1463 }
1464 
1465 VCHIQ_STATE_T *
1466 vchiq_get_state(void)
1467 {
1468 
1469 	if (g_state.remote == NULL)
1470 		printk(KERN_ERR "%s: g_state.remote == NULL\n", __func__);
1471 	else if (g_state.remote->initialised != 1)
1472 		printk(KERN_NOTICE "%s: g_state.remote->initialised != 1 (%d)\n",
1473 			__func__, g_state.remote->initialised);
1474 
1475 	return ((g_state.remote != NULL) &&
1476 		(g_state.remote->initialised == 1)) ? &g_state : NULL;
1477 }
1478 
1479 /*
1480  * Autosuspend related functionality
1481  */
1482 
1483 int
1484 vchiq_videocore_wanted(VCHIQ_STATE_T *state)
1485 {
1486 	VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
1487 	if (!arm_state)
1488 		/* autosuspend not supported - always return wanted */
1489 		return 1;
1490 	else if (arm_state->blocked_count)
1491 		return 1;
1492 	else if (!arm_state->videocore_use_count)
1493 		/* usage count zero - check for override unless we're forcing */
1494 		if (arm_state->resume_blocked)
1495 			return 0;
1496 		else
1497 			return vchiq_platform_videocore_wanted(state);
1498 	else
1499 		/* non-zero usage count - videocore still required */
1500 		return 1;
1501 }
1502 
1503 static VCHIQ_STATUS_T
1504 vchiq_keepalive_vchiq_callback(VCHIQ_REASON_T reason,
1505 	VCHIQ_HEADER_T *header,
1506 	VCHIQ_SERVICE_HANDLE_T service_user,
1507 	void *bulk_user)
1508 {
1509 	vchiq_log_error(vchiq_susp_log_level,
1510 		"%s callback reason %d", __func__, reason);
1511 	return 0;
1512 }
1513 
1514 static int
1515 vchiq_keepalive_thread_func(void *v)
1516 {
1517 	VCHIQ_STATE_T *state = (VCHIQ_STATE_T *) v;
1518 	VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
1519 
1520 	VCHIQ_STATUS_T status;
1521 	VCHIQ_INSTANCE_T instance;
1522 	VCHIQ_SERVICE_HANDLE_T ka_handle;
1523 
1524 	VCHIQ_SERVICE_PARAMS_T params = {
1525 		.fourcc      = VCHIQ_MAKE_FOURCC('K', 'E', 'E', 'P'),
1526 		.callback    = vchiq_keepalive_vchiq_callback,
1527 		.version     = KEEPALIVE_VER,
1528 		.version_min = KEEPALIVE_VER_MIN
1529 	};
1530 
1531 	status = vchiq_initialise(&instance);
1532 	if (status != VCHIQ_SUCCESS) {
1533 		vchiq_log_error(vchiq_susp_log_level,
1534 			"%s vchiq_initialise failed %d", __func__, status);
1535 		goto exit;
1536 	}
1537 
1538 	status = vchiq_connect(instance);
1539 	if (status != VCHIQ_SUCCESS) {
1540 		vchiq_log_error(vchiq_susp_log_level,
1541 			"%s vchiq_connect failed %d", __func__, status);
1542 		goto shutdown;
1543 	}
1544 
1545 	status = vchiq_add_service(instance, &params, &ka_handle);
1546 	if (status != VCHIQ_SUCCESS) {
1547 		vchiq_log_error(vchiq_susp_log_level,
1548 			"%s vchiq_open_service failed %d", __func__, status);
1549 		goto shutdown;
1550 	}
1551 
1552 	while (1) {
1553 		long rc = 0, uc = 0;
1554 		if (wait_for_completion_interruptible(&arm_state->ka_evt)
1555 				!= 0) {
1556 			vchiq_log_error(vchiq_susp_log_level,
1557 				"%s interrupted", __func__);
1558 			flush_signals(current);
1559 			continue;
1560 		}
1561 
1562 		/* read and clear counters.  Do release_count then use_count to
1563 		 * prevent getting more releases than uses */
1564 		rc = atomic_xchg(&arm_state->ka_release_count, 0);
1565 		uc = atomic_xchg(&arm_state->ka_use_count, 0);
1566 
1567 		/* Call use/release service the requisite number of times.
1568 		 * Process use before release so use counts don't go negative */
1569 		while (uc--) {
1570 			atomic_inc(&arm_state->ka_use_ack_count);
1571 			status = vchiq_use_service(ka_handle);
1572 			if (status != VCHIQ_SUCCESS) {
1573 				vchiq_log_error(vchiq_susp_log_level,
1574 					"%s vchiq_use_service error %d",
1575 					__func__, status);
1576 			}
1577 		}
1578 		while (rc--) {
1579 			status = vchiq_release_service(ka_handle);
1580 			if (status != VCHIQ_SUCCESS) {
1581 				vchiq_log_error(vchiq_susp_log_level,
1582 					"%s vchiq_release_service error %d",
1583 					__func__, status);
1584 			}
1585 		}
1586 	}
1587 
1588 shutdown:
1589 	vchiq_shutdown(instance);
1590 exit:
1591 	return 0;
1592 }
1593 
1594 VCHIQ_STATUS_T
1595 vchiq_arm_init_state(VCHIQ_STATE_T *state, VCHIQ_ARM_STATE_T *arm_state)
1596 {
1597 	VCHIQ_STATUS_T status = VCHIQ_SUCCESS;
1598 
1599 	if (arm_state) {
1600 		rwlock_init(&arm_state->susp_res_lock);
1601 
1602 		init_completion(&arm_state->ka_evt);
1603 		atomic_set(&arm_state->ka_use_count, 0);
1604 		atomic_set(&arm_state->ka_use_ack_count, 0);
1605 		atomic_set(&arm_state->ka_release_count, 0);
1606 
1607 		init_completion(&arm_state->vc_suspend_complete);
1608 
1609 		init_completion(&arm_state->vc_resume_complete);
1610 		/* Initialise to 'done' state.  We only want to block on resume
1611 		 * completion while videocore is suspended. */
1612 		set_resume_state(arm_state, VC_RESUME_RESUMED);
1613 
1614 		init_completion(&arm_state->resume_blocker);
1615 		/* Initialise to 'done' state.  We only want to block on this
1616 		 * completion while resume is blocked */
1617 		complete_all(&arm_state->resume_blocker);
1618 
1619 		init_completion(&arm_state->blocked_blocker);
1620 		/* Initialise to 'done' state.  We only want to block on this
1621 		 * completion while things are waiting on the resume blocker */
1622 		complete_all(&arm_state->blocked_blocker);
1623 
1624 		arm_state->suspend_timer_timeout = SUSPEND_TIMER_TIMEOUT_MS;
1625 		arm_state->suspend_timer_running = 0;
1626 		init_timer(&arm_state->suspend_timer);
1627 		arm_state->suspend_timer.data = (unsigned long)(state);
1628 		arm_state->suspend_timer.function = suspend_timer_callback;
1629 
1630 		arm_state->first_connect = 0;
1631 
1632 	}
1633 	return status;
1634 }
1635 
1636 /*
1637 ** Functions to modify the state variables;
1638 **	set_suspend_state
1639 **	set_resume_state
1640 **
1641 ** There are more state variables than we might like, so ensure they remain in
1642 ** step.  Suspend and resume state are maintained separately, since most of
1643 ** these state machines can operate independently.  However, there are a few
1644 ** states where state transitions in one state machine cause a reset to the
1645 ** other state machine.  In addition, there are some completion events which
1646 ** need to occur on state machine reset and end-state(s), so these are also
1647 ** dealt with in these functions.
1648 **
1649 ** In all states we set the state variable according to the input, but in some
1650 ** cases we perform additional steps outlined below;
1651 **
1652 ** VC_SUSPEND_IDLE - Initialise the suspend completion at the same time.
1653 **			The suspend completion is completed after any suspend
1654 **			attempt.  When we reset the state machine we also reset
1655 **			the completion.  This reset occurs when videocore is
1656 **			resumed, and also if we initiate suspend after a suspend
1657 **			failure.
1658 **
1659 ** VC_SUSPEND_IN_PROGRESS - This state is considered the point of no return for
1660 **			suspend - ie from this point on we must try to suspend
1661 **			before resuming can occur.  We therefore also reset the
1662 **			resume state machine to VC_RESUME_IDLE in this state.
1663 **
1664 ** VC_SUSPEND_SUSPENDED - Suspend has completed successfully. Also call
1665 **			complete_all on the suspend completion to notify
1666 **			anything waiting for suspend to happen.
1667 **
1668 ** VC_SUSPEND_REJECTED - Videocore rejected suspend. Videocore will also
1669 **			initiate resume, so no need to alter resume state.
1670 **			We call complete_all on the suspend completion to notify
1671 **			of suspend rejection.
1672 **
1673 ** VC_SUSPEND_FAILED - We failed to initiate videocore suspend.  We notify the
1674 **			suspend completion and reset the resume state machine.
1675 **
1676 ** VC_RESUME_IDLE - Initialise the resume completion at the same time.  The
1677 **			resume completion is in it's 'done' state whenever
1678 **			videcore is running.  Therfore, the VC_RESUME_IDLE state
1679 **			implies that videocore is suspended.
1680 **			Hence, any thread which needs to wait until videocore is
1681 **			running can wait on this completion - it will only block
1682 **			if videocore is suspended.
1683 **
1684 ** VC_RESUME_RESUMED - Resume has completed successfully.  Videocore is running.
1685 **			Call complete_all on the resume completion to unblock
1686 **			any threads waiting for resume.	 Also reset the suspend
1687 **			state machine to it's idle state.
1688 **
1689 ** VC_RESUME_FAILED - Currently unused - no mechanism to fail resume exists.
1690 */
1691 
1692 inline void
1693 set_suspend_state(VCHIQ_ARM_STATE_T *arm_state,
1694 	enum vc_suspend_status new_state)
1695 {
1696 	/* set the state in all cases */
1697 	arm_state->vc_suspend_state = new_state;
1698 
1699 	/* state specific additional actions */
1700 	switch (new_state) {
1701 	case VC_SUSPEND_FORCE_CANCELED:
1702 		complete_all(&arm_state->vc_suspend_complete);
1703 		break;
1704 	case VC_SUSPEND_REJECTED:
1705 		complete_all(&arm_state->vc_suspend_complete);
1706 		break;
1707 	case VC_SUSPEND_FAILED:
1708 		complete_all(&arm_state->vc_suspend_complete);
1709 		arm_state->vc_resume_state = VC_RESUME_RESUMED;
1710 		complete_all(&arm_state->vc_resume_complete);
1711 		break;
1712 	case VC_SUSPEND_IDLE:
1713 		INIT_COMPLETION(arm_state->vc_suspend_complete);
1714 		break;
1715 	case VC_SUSPEND_REQUESTED:
1716 		break;
1717 	case VC_SUSPEND_IN_PROGRESS:
1718 		set_resume_state(arm_state, VC_RESUME_IDLE);
1719 		break;
1720 	case VC_SUSPEND_SUSPENDED:
1721 		complete_all(&arm_state->vc_suspend_complete);
1722 		break;
1723 	default:
1724 		BUG();
1725 		break;
1726 	}
1727 }
1728 
1729 inline void
1730 set_resume_state(VCHIQ_ARM_STATE_T *arm_state,
1731 	enum vc_resume_status new_state)
1732 {
1733 	/* set the state in all cases */
1734 	arm_state->vc_resume_state = new_state;
1735 
1736 	/* state specific additional actions */
1737 	switch (new_state) {
1738 	case VC_RESUME_FAILED:
1739 		break;
1740 	case VC_RESUME_IDLE:
1741 		INIT_COMPLETION(arm_state->vc_resume_complete);
1742 		break;
1743 	case VC_RESUME_REQUESTED:
1744 		break;
1745 	case VC_RESUME_IN_PROGRESS:
1746 		break;
1747 	case VC_RESUME_RESUMED:
1748 		complete_all(&arm_state->vc_resume_complete);
1749 		set_suspend_state(arm_state, VC_SUSPEND_IDLE);
1750 		break;
1751 	default:
1752 		BUG();
1753 		break;
1754 	}
1755 }
1756 
1757 
1758 /* should be called with the write lock held */
1759 inline void
1760 start_suspend_timer(VCHIQ_ARM_STATE_T *arm_state)
1761 {
1762 	del_timer(&arm_state->suspend_timer);
1763 	arm_state->suspend_timer.expires = jiffies +
1764 		msecs_to_jiffies(arm_state->
1765 			suspend_timer_timeout);
1766 	add_timer(&arm_state->suspend_timer);
1767 	arm_state->suspend_timer_running = 1;
1768 }
1769 
1770 /* should be called with the write lock held */
1771 static inline void
1772 stop_suspend_timer(VCHIQ_ARM_STATE_T *arm_state)
1773 {
1774 	if (arm_state->suspend_timer_running) {
1775 		del_timer(&arm_state->suspend_timer);
1776 		arm_state->suspend_timer_running = 0;
1777 	}
1778 }
1779 
1780 static inline int
1781 need_resume(VCHIQ_STATE_T *state)
1782 {
1783 	VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
1784 	return (arm_state->vc_suspend_state > VC_SUSPEND_IDLE) &&
1785 			(arm_state->vc_resume_state < VC_RESUME_REQUESTED) &&
1786 			vchiq_videocore_wanted(state);
1787 }
1788 
1789 static int
1790 block_resume(VCHIQ_ARM_STATE_T *arm_state)
1791 {
1792 	int status = VCHIQ_SUCCESS;
1793 	const unsigned long timeout_val =
1794 				msecs_to_jiffies(FORCE_SUSPEND_TIMEOUT_MS);
1795 	int resume_count = 0;
1796 
1797 	/* Allow any threads which were blocked by the last force suspend to
1798 	 * complete if they haven't already.  Only give this one shot; if
1799 	 * blocked_count is incremented after blocked_blocker is completed
1800 	 * (which only happens when blocked_count hits 0) then those threads
1801 	 * will have to wait until next time around */
1802 	if (arm_state->blocked_count) {
1803 		INIT_COMPLETION(arm_state->blocked_blocker);
1804 		write_unlock_bh(&arm_state->susp_res_lock);
1805 		vchiq_log_info(vchiq_susp_log_level, "%s wait for previously "
1806 			"blocked clients", __func__);
1807 		if (wait_for_completion_interruptible_timeout(
1808 				&arm_state->blocked_blocker, timeout_val)
1809 					<= 0) {
1810 			vchiq_log_error(vchiq_susp_log_level, "%s wait for "
1811 				"previously blocked clients failed" , __func__);
1812 			status = VCHIQ_ERROR;
1813 			write_lock_bh(&arm_state->susp_res_lock);
1814 			goto out;
1815 		}
1816 		vchiq_log_info(vchiq_susp_log_level, "%s previously blocked "
1817 			"clients resumed", __func__);
1818 		write_lock_bh(&arm_state->susp_res_lock);
1819 	}
1820 
1821 	/* We need to wait for resume to complete if it's in process */
1822 	while (arm_state->vc_resume_state != VC_RESUME_RESUMED &&
1823 			arm_state->vc_resume_state > VC_RESUME_IDLE) {
1824 		if (resume_count > 1) {
1825 			status = VCHIQ_ERROR;
1826 			vchiq_log_error(vchiq_susp_log_level, "%s waited too "
1827 				"many times for resume" , __func__);
1828 			goto out;
1829 		}
1830 		write_unlock_bh(&arm_state->susp_res_lock);
1831 		vchiq_log_info(vchiq_susp_log_level, "%s wait for resume",
1832 			__func__);
1833 		if (wait_for_completion_interruptible_timeout(
1834 				&arm_state->vc_resume_complete, timeout_val)
1835 					<= 0) {
1836 			vchiq_log_error(vchiq_susp_log_level, "%s wait for "
1837 				"resume failed (%s)", __func__,
1838 				resume_state_names[arm_state->vc_resume_state +
1839 							VC_RESUME_NUM_OFFSET]);
1840 			status = VCHIQ_ERROR;
1841 			write_lock_bh(&arm_state->susp_res_lock);
1842 			goto out;
1843 		}
1844 		vchiq_log_info(vchiq_susp_log_level, "%s resumed", __func__);
1845 		write_lock_bh(&arm_state->susp_res_lock);
1846 		resume_count++;
1847 	}
1848 	INIT_COMPLETION(arm_state->resume_blocker);
1849 	arm_state->resume_blocked = 1;
1850 
1851 out:
1852 	return status;
1853 }
1854 
1855 static inline void
1856 unblock_resume(VCHIQ_ARM_STATE_T *arm_state)
1857 {
1858 	complete_all(&arm_state->resume_blocker);
1859 	arm_state->resume_blocked = 0;
1860 }
1861 
1862 /* Initiate suspend via slot handler. Should be called with the write lock
1863  * held */
1864 VCHIQ_STATUS_T
1865 vchiq_arm_vcsuspend(VCHIQ_STATE_T *state)
1866 {
1867 	VCHIQ_STATUS_T status = VCHIQ_ERROR;
1868 	VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
1869 
1870 	if (!arm_state)
1871 		goto out;
1872 
1873 	vchiq_log_trace(vchiq_susp_log_level, "%s", __func__);
1874 	status = VCHIQ_SUCCESS;
1875 
1876 
1877 	switch (arm_state->vc_suspend_state) {
1878 	case VC_SUSPEND_REQUESTED:
1879 		vchiq_log_info(vchiq_susp_log_level, "%s: suspend already "
1880 			"requested", __func__);
1881 		break;
1882 	case VC_SUSPEND_IN_PROGRESS:
1883 		vchiq_log_info(vchiq_susp_log_level, "%s: suspend already in "
1884 			"progress", __func__);
1885 		break;
1886 
1887 	default:
1888 		/* We don't expect to be in other states, so log but continue
1889 		 * anyway */
1890 		vchiq_log_error(vchiq_susp_log_level,
1891 			"%s unexpected suspend state %s", __func__,
1892 			suspend_state_names[arm_state->vc_suspend_state +
1893 						VC_SUSPEND_NUM_OFFSET]);
1894 		/* fall through */
1895 	case VC_SUSPEND_REJECTED:
1896 	case VC_SUSPEND_FAILED:
1897 		/* Ensure any idle state actions have been run */
1898 		set_suspend_state(arm_state, VC_SUSPEND_IDLE);
1899 		/* fall through */
1900 	case VC_SUSPEND_IDLE:
1901 		vchiq_log_info(vchiq_susp_log_level,
1902 			"%s: suspending", __func__);
1903 		set_suspend_state(arm_state, VC_SUSPEND_REQUESTED);
1904 		/* kick the slot handler thread to initiate suspend */
1905 		request_poll(state, NULL, 0);
1906 		break;
1907 	}
1908 
1909 out:
1910 	vchiq_log_trace(vchiq_susp_log_level, "%s exit %d", __func__, status);
1911 	return status;
1912 }
1913 
1914 void
1915 vchiq_platform_check_suspend(VCHIQ_STATE_T *state)
1916 {
1917 	VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
1918 	int susp = 0;
1919 
1920 	if (!arm_state)
1921 		goto out;
1922 
1923 	vchiq_log_trace(vchiq_susp_log_level, "%s", __func__);
1924 
1925 	write_lock_bh(&arm_state->susp_res_lock);
1926 	if (arm_state->vc_suspend_state == VC_SUSPEND_REQUESTED &&
1927 			arm_state->vc_resume_state == VC_RESUME_RESUMED) {
1928 		set_suspend_state(arm_state, VC_SUSPEND_IN_PROGRESS);
1929 		susp = 1;
1930 	}
1931 	write_unlock_bh(&arm_state->susp_res_lock);
1932 
1933 	if (susp)
1934 		vchiq_platform_suspend(state);
1935 
1936 out:
1937 	vchiq_log_trace(vchiq_susp_log_level, "%s exit", __func__);
1938 	return;
1939 }
1940 
1941 
1942 static void
1943 output_timeout_error(VCHIQ_STATE_T *state)
1944 {
1945 	VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
1946 	char service_err[50] = "";
1947 	int vc_use_count = arm_state->videocore_use_count;
1948 	int active_services = state->unused_service;
1949 	int i;
1950 
1951 	if (!arm_state->videocore_use_count) {
1952 		snprintf(service_err, 50, " Videocore usecount is 0");
1953 		goto output_msg;
1954 	}
1955 	for (i = 0; i < active_services; i++) {
1956 		VCHIQ_SERVICE_T *service_ptr = state->services[i];
1957 		if (service_ptr && service_ptr->service_use_count &&
1958 			(service_ptr->srvstate != VCHIQ_SRVSTATE_FREE)) {
1959 			snprintf(service_err, 50, " %c%c%c%c(%8x) service has "
1960 				"use count %d%s", VCHIQ_FOURCC_AS_4CHARS(
1961 					service_ptr->base.fourcc),
1962 				 service_ptr->client_id,
1963 				 service_ptr->service_use_count,
1964 				 service_ptr->service_use_count ==
1965 					 vc_use_count ? "" : " (+ more)");
1966 			break;
1967 		}
1968 	}
1969 
1970 output_msg:
1971 	vchiq_log_error(vchiq_susp_log_level,
1972 		"timed out waiting for vc suspend (%d).%s",
1973 		 arm_state->autosuspend_override, service_err);
1974 
1975 }
1976 
1977 /* Try to get videocore into suspended state, regardless of autosuspend state.
1978 ** We don't actually force suspend, since videocore may get into a bad state
1979 ** if we force suspend at a bad time.  Instead, we wait for autosuspend to
1980 ** determine a good point to suspend.  If this doesn't happen within 100ms we
1981 ** report failure.
1982 **
1983 ** Returns VCHIQ_SUCCESS if videocore suspended successfully, VCHIQ_RETRY if
1984 ** videocore failed to suspend in time or VCHIQ_ERROR if interrupted.
1985 */
1986 VCHIQ_STATUS_T
1987 vchiq_arm_force_suspend(VCHIQ_STATE_T *state)
1988 {
1989 	VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
1990 	VCHIQ_STATUS_T status = VCHIQ_ERROR;
1991 	long rc = 0;
1992 	int repeat = -1;
1993 
1994 	if (!arm_state)
1995 		goto out;
1996 
1997 	vchiq_log_trace(vchiq_susp_log_level, "%s", __func__);
1998 
1999 	write_lock_bh(&arm_state->susp_res_lock);
2000 
2001 	status = block_resume(arm_state);
2002 	if (status != VCHIQ_SUCCESS)
2003 		goto unlock;
2004 	if (arm_state->vc_suspend_state == VC_SUSPEND_SUSPENDED) {
2005 		/* Already suspended - just block resume and exit */
2006 		vchiq_log_info(vchiq_susp_log_level, "%s already suspended",
2007 			__func__);
2008 		status = VCHIQ_SUCCESS;
2009 		goto unlock;
2010 	} else if (arm_state->vc_suspend_state <= VC_SUSPEND_IDLE) {
2011 		/* initiate suspend immediately in the case that we're waiting
2012 		 * for the timeout */
2013 		stop_suspend_timer(arm_state);
2014 		if (!vchiq_videocore_wanted(state)) {
2015 			vchiq_log_info(vchiq_susp_log_level, "%s videocore "
2016 				"idle, initiating suspend", __func__);
2017 			status = vchiq_arm_vcsuspend(state);
2018 		} else if (arm_state->autosuspend_override <
2019 						FORCE_SUSPEND_FAIL_MAX) {
2020 			vchiq_log_info(vchiq_susp_log_level, "%s letting "
2021 				"videocore go idle", __func__);
2022 			status = VCHIQ_SUCCESS;
2023 		} else {
2024 			vchiq_log_warning(vchiq_susp_log_level, "%s failed too "
2025 				"many times - attempting suspend", __func__);
2026 			status = vchiq_arm_vcsuspend(state);
2027 		}
2028 	} else {
2029 		vchiq_log_info(vchiq_susp_log_level, "%s videocore suspend "
2030 			"in progress - wait for completion", __func__);
2031 		status = VCHIQ_SUCCESS;
2032 	}
2033 
2034 	/* Wait for suspend to happen due to system idle (not forced..) */
2035 	if (status != VCHIQ_SUCCESS)
2036 		goto unblock_resume;
2037 
2038 	do {
2039 		write_unlock_bh(&arm_state->susp_res_lock);
2040 
2041 		rc = wait_for_completion_interruptible_timeout(
2042 				&arm_state->vc_suspend_complete,
2043 				msecs_to_jiffies(FORCE_SUSPEND_TIMEOUT_MS));
2044 
2045 		write_lock_bh(&arm_state->susp_res_lock);
2046 		if (rc < 0) {
2047 			vchiq_log_warning(vchiq_susp_log_level, "%s "
2048 				"interrupted waiting for suspend", __func__);
2049 			status = VCHIQ_ERROR;
2050 			goto unblock_resume;
2051 		} else if (rc == 0) {
2052 			if (arm_state->vc_suspend_state > VC_SUSPEND_IDLE) {
2053 				/* Repeat timeout once if in progress */
2054 				if (repeat < 0) {
2055 					repeat = 1;
2056 					continue;
2057 				}
2058 			}
2059 			arm_state->autosuspend_override++;
2060 			output_timeout_error(state);
2061 
2062 			status = VCHIQ_RETRY;
2063 			goto unblock_resume;
2064 		}
2065 	} while (0 < (repeat--));
2066 
2067 	/* Check and report state in case we need to abort ARM suspend */
2068 	if (arm_state->vc_suspend_state != VC_SUSPEND_SUSPENDED) {
2069 		status = VCHIQ_RETRY;
2070 		vchiq_log_error(vchiq_susp_log_level,
2071 			"%s videocore suspend failed (state %s)", __func__,
2072 			suspend_state_names[arm_state->vc_suspend_state +
2073 						VC_SUSPEND_NUM_OFFSET]);
2074 		/* Reset the state only if it's still in an error state.
2075 		 * Something could have already initiated another suspend. */
2076 		if (arm_state->vc_suspend_state < VC_SUSPEND_IDLE)
2077 			set_suspend_state(arm_state, VC_SUSPEND_IDLE);
2078 
2079 		goto unblock_resume;
2080 	}
2081 
2082 	/* successfully suspended - unlock and exit */
2083 	goto unlock;
2084 
2085 unblock_resume:
2086 	/* all error states need to unblock resume before exit */
2087 	unblock_resume(arm_state);
2088 
2089 unlock:
2090 	write_unlock_bh(&arm_state->susp_res_lock);
2091 
2092 out:
2093 	vchiq_log_trace(vchiq_susp_log_level, "%s exit %d", __func__, status);
2094 	return status;
2095 }
2096 
2097 void
2098 vchiq_check_suspend(VCHIQ_STATE_T *state)
2099 {
2100 	VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
2101 
2102 	if (!arm_state)
2103 		goto out;
2104 
2105 	vchiq_log_trace(vchiq_susp_log_level, "%s", __func__);
2106 
2107 	write_lock_bh(&arm_state->susp_res_lock);
2108 	if (arm_state->vc_suspend_state != VC_SUSPEND_SUSPENDED &&
2109 			arm_state->first_connect &&
2110 			!vchiq_videocore_wanted(state)) {
2111 		vchiq_arm_vcsuspend(state);
2112 	}
2113 	write_unlock_bh(&arm_state->susp_res_lock);
2114 
2115 out:
2116 	vchiq_log_trace(vchiq_susp_log_level, "%s exit", __func__);
2117 	return;
2118 }
2119 
2120 
2121 int
2122 vchiq_arm_allow_resume(VCHIQ_STATE_T *state)
2123 {
2124 	VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
2125 	int resume = 0;
2126 	int ret = -1;
2127 
2128 	if (!arm_state)
2129 		goto out;
2130 
2131 	vchiq_log_trace(vchiq_susp_log_level, "%s", __func__);
2132 
2133 	write_lock_bh(&arm_state->susp_res_lock);
2134 	unblock_resume(arm_state);
2135 	resume = vchiq_check_resume(state);
2136 	write_unlock_bh(&arm_state->susp_res_lock);
2137 
2138 	if (resume) {
2139 		if (wait_for_completion_interruptible(
2140 			&arm_state->vc_resume_complete) < 0) {
2141 			vchiq_log_error(vchiq_susp_log_level,
2142 				"%s interrupted", __func__);
2143 			/* failed, cannot accurately derive suspend
2144 			 * state, so exit early. */
2145 			goto out;
2146 		}
2147 	}
2148 
2149 	read_lock_bh(&arm_state->susp_res_lock);
2150 	if (arm_state->vc_suspend_state == VC_SUSPEND_SUSPENDED) {
2151 		vchiq_log_info(vchiq_susp_log_level,
2152 				"%s: Videocore remains suspended", __func__);
2153 	} else {
2154 		vchiq_log_info(vchiq_susp_log_level,
2155 				"%s: Videocore resumed", __func__);
2156 		ret = 0;
2157 	}
2158 	read_unlock_bh(&arm_state->susp_res_lock);
2159 out:
2160 	vchiq_log_trace(vchiq_susp_log_level, "%s exit %d", __func__, ret);
2161 	return ret;
2162 }
2163 
2164 /* This function should be called with the write lock held */
2165 int
2166 vchiq_check_resume(VCHIQ_STATE_T *state)
2167 {
2168 	VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
2169 	int resume = 0;
2170 
2171 	if (!arm_state)
2172 		goto out;
2173 
2174 	vchiq_log_trace(vchiq_susp_log_level, "%s", __func__);
2175 
2176 	if (need_resume(state)) {
2177 		set_resume_state(arm_state, VC_RESUME_REQUESTED);
2178 		request_poll(state, NULL, 0);
2179 		resume = 1;
2180 	}
2181 
2182 out:
2183 	vchiq_log_trace(vchiq_susp_log_level, "%s exit", __func__);
2184 	return resume;
2185 }
2186 
2187 #ifdef notyet
2188 void
2189 vchiq_platform_check_resume(VCHIQ_STATE_T *state)
2190 {
2191 	VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
2192 	int res = 0;
2193 
2194 	if (!arm_state)
2195 		goto out;
2196 
2197 	vchiq_log_trace(vchiq_susp_log_level, "%s", __func__);
2198 
2199 	write_lock_bh(&arm_state->susp_res_lock);
2200 	if (arm_state->wake_address == 0) {
2201 		vchiq_log_info(vchiq_susp_log_level,
2202 					"%s: already awake", __func__);
2203 		goto unlock;
2204 	}
2205 	if (arm_state->vc_resume_state == VC_RESUME_IN_PROGRESS) {
2206 		vchiq_log_info(vchiq_susp_log_level,
2207 					"%s: already resuming", __func__);
2208 		goto unlock;
2209 	}
2210 
2211 	if (arm_state->vc_resume_state == VC_RESUME_REQUESTED) {
2212 		set_resume_state(arm_state, VC_RESUME_IN_PROGRESS);
2213 		res = 1;
2214 	} else
2215 		vchiq_log_trace(vchiq_susp_log_level,
2216 				"%s: not resuming (resume state %s)", __func__,
2217 				resume_state_names[arm_state->vc_resume_state +
2218 							VC_RESUME_NUM_OFFSET]);
2219 
2220 unlock:
2221 	write_unlock_bh(&arm_state->susp_res_lock);
2222 
2223 	if (res)
2224 		vchiq_platform_resume(state);
2225 
2226 out:
2227 	vchiq_log_trace(vchiq_susp_log_level, "%s exit", __func__);
2228 	return;
2229 
2230 }
2231 #endif
2232 
2233 
2234 
2235 VCHIQ_STATUS_T
2236 vchiq_use_internal(VCHIQ_STATE_T *state, VCHIQ_SERVICE_T *service,
2237 		enum USE_TYPE_E use_type)
2238 {
2239 	VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
2240 	VCHIQ_STATUS_T ret = VCHIQ_SUCCESS;
2241 	char entity[16];
2242 	int *entity_uc;
2243 	int local_uc, local_entity_uc;
2244 
2245 	if (!arm_state)
2246 		goto out;
2247 
2248 	vchiq_log_trace(vchiq_susp_log_level, "%s", __func__);
2249 
2250 	if (use_type == USE_TYPE_VCHIQ) {
2251 		snprintf(entity, sizeof(entity), "VCHIQ:   ");
2252 		entity_uc = &arm_state->peer_use_count;
2253 	} else if (service) {
2254 		snprintf(entity, sizeof(entity), "%c%c%c%c:%8x",
2255 			VCHIQ_FOURCC_AS_4CHARS(service->base.fourcc),
2256 			service->client_id);
2257 		entity_uc = &service->service_use_count;
2258 	} else {
2259 		vchiq_log_error(vchiq_susp_log_level, "%s null service "
2260 				"ptr", __func__);
2261 		ret = VCHIQ_ERROR;
2262 		goto out;
2263 	}
2264 
2265 	write_lock_bh(&arm_state->susp_res_lock);
2266 	while (arm_state->resume_blocked) {
2267 		/* If we call 'use' while force suspend is waiting for suspend,
2268 		 * then we're about to block the thread which the force is
2269 		 * waiting to complete, so we're bound to just time out. In this
2270 		 * case, set the suspend state such that the wait will be
2271 		 * canceled, so we can complete as quickly as possible. */
2272 		if (arm_state->resume_blocked && arm_state->vc_suspend_state ==
2273 				VC_SUSPEND_IDLE) {
2274 			set_suspend_state(arm_state, VC_SUSPEND_FORCE_CANCELED);
2275 			break;
2276 		}
2277 		/* If suspend is already in progress then we need to block */
2278 		if (!try_wait_for_completion(&arm_state->resume_blocker)) {
2279 			/* Indicate that there are threads waiting on the resume
2280 			 * blocker.  These need to be allowed to complete before
2281 			 * a _second_ call to force suspend can complete,
2282 			 * otherwise low priority threads might never actually
2283 			 * continue */
2284 			arm_state->blocked_count++;
2285 			write_unlock_bh(&arm_state->susp_res_lock);
2286 			vchiq_log_info(vchiq_susp_log_level, "%s %s resume "
2287 				"blocked - waiting...", __func__, entity);
2288 			if (wait_for_completion_killable(
2289 					&arm_state->resume_blocker) != 0) {
2290 				vchiq_log_error(vchiq_susp_log_level, "%s %s "
2291 					"wait for resume blocker interrupted",
2292 					__func__, entity);
2293 				ret = VCHIQ_ERROR;
2294 				write_lock_bh(&arm_state->susp_res_lock);
2295 				arm_state->blocked_count--;
2296 				write_unlock_bh(&arm_state->susp_res_lock);
2297 				goto out;
2298 			}
2299 			vchiq_log_info(vchiq_susp_log_level, "%s %s resume "
2300 				"unblocked", __func__, entity);
2301 			write_lock_bh(&arm_state->susp_res_lock);
2302 			if (--arm_state->blocked_count == 0)
2303 				complete_all(&arm_state->blocked_blocker);
2304 		}
2305 	}
2306 
2307 	stop_suspend_timer(arm_state);
2308 
2309 	local_uc = ++arm_state->videocore_use_count;
2310 	local_entity_uc = ++(*entity_uc);
2311 
2312 	/* If there's a pending request which hasn't yet been serviced then
2313 	 * just clear it.  If we're past VC_SUSPEND_REQUESTED state then
2314 	 * vc_resume_complete will block until we either resume or fail to
2315 	 * suspend */
2316 	if (arm_state->vc_suspend_state <= VC_SUSPEND_REQUESTED)
2317 		set_suspend_state(arm_state, VC_SUSPEND_IDLE);
2318 
2319 	if ((use_type != USE_TYPE_SERVICE_NO_RESUME) && need_resume(state)) {
2320 		set_resume_state(arm_state, VC_RESUME_REQUESTED);
2321 		vchiq_log_info(vchiq_susp_log_level,
2322 			"%s %s count %d, state count %d",
2323 			__func__, entity, local_entity_uc, local_uc);
2324 		request_poll(state, NULL, 0);
2325 	} else
2326 		vchiq_log_trace(vchiq_susp_log_level,
2327 			"%s %s count %d, state count %d",
2328 			__func__, entity, *entity_uc, local_uc);
2329 
2330 
2331 	write_unlock_bh(&arm_state->susp_res_lock);
2332 
2333 	/* Completion is in a done state when we're not suspended, so this won't
2334 	 * block for the non-suspended case. */
2335 	if (!try_wait_for_completion(&arm_state->vc_resume_complete)) {
2336 		vchiq_log_info(vchiq_susp_log_level, "%s %s wait for resume",
2337 			__func__, entity);
2338 		if (wait_for_completion_killable(
2339 				&arm_state->vc_resume_complete) != 0) {
2340 			vchiq_log_error(vchiq_susp_log_level, "%s %s wait for "
2341 				"resume interrupted", __func__, entity);
2342 			ret = VCHIQ_ERROR;
2343 			goto out;
2344 		}
2345 		vchiq_log_info(vchiq_susp_log_level, "%s %s resumed", __func__,
2346 			entity);
2347 	}
2348 
2349 	if (ret == VCHIQ_SUCCESS) {
2350 		VCHIQ_STATUS_T status = VCHIQ_SUCCESS;
2351 		long ack_cnt = atomic_xchg(&arm_state->ka_use_ack_count, 0);
2352 		while (ack_cnt && (status == VCHIQ_SUCCESS)) {
2353 			/* Send the use notify to videocore */
2354 			status = vchiq_send_remote_use_active(state);
2355 			if (status == VCHIQ_SUCCESS)
2356 				ack_cnt--;
2357 			else
2358 				atomic_add(ack_cnt,
2359 					&arm_state->ka_use_ack_count);
2360 		}
2361 	}
2362 
2363 out:
2364 	vchiq_log_trace(vchiq_susp_log_level, "%s exit %d", __func__, ret);
2365 	return ret;
2366 }
2367 
2368 VCHIQ_STATUS_T
2369 vchiq_release_internal(VCHIQ_STATE_T *state, VCHIQ_SERVICE_T *service)
2370 {
2371 	VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
2372 	VCHIQ_STATUS_T ret = VCHIQ_SUCCESS;
2373 	char entity[16];
2374 	int *entity_uc;
2375 
2376 	if (!arm_state)
2377 		goto out;
2378 
2379 	vchiq_log_trace(vchiq_susp_log_level, "%s", __func__);
2380 
2381 	if (service) {
2382 		snprintf(entity, sizeof(entity), "%c%c%c%c:%8x",
2383 			VCHIQ_FOURCC_AS_4CHARS(service->base.fourcc),
2384 			service->client_id);
2385 		entity_uc = &service->service_use_count;
2386 	} else {
2387 		snprintf(entity, sizeof(entity), "PEER:   ");
2388 		entity_uc = &arm_state->peer_use_count;
2389 	}
2390 
2391 	write_lock_bh(&arm_state->susp_res_lock);
2392 	if (!arm_state->videocore_use_count || !(*entity_uc)) {
2393 		/* Don't use BUG_ON - don't allow user thread to crash kernel */
2394 		WARN_ON(!arm_state->videocore_use_count);
2395 		WARN_ON(!(*entity_uc));
2396 		ret = VCHIQ_ERROR;
2397 		goto unlock;
2398 	}
2399 	--arm_state->videocore_use_count;
2400 	--(*entity_uc);
2401 
2402 	if (!vchiq_videocore_wanted(state)) {
2403 		if (vchiq_platform_use_suspend_timer() &&
2404 				!arm_state->resume_blocked) {
2405 			/* Only use the timer if we're not trying to force
2406 			 * suspend (=> resume_blocked) */
2407 			start_suspend_timer(arm_state);
2408 		} else {
2409 			vchiq_log_info(vchiq_susp_log_level,
2410 				"%s %s count %d, state count %d - suspending",
2411 				__func__, entity, *entity_uc,
2412 				arm_state->videocore_use_count);
2413 			vchiq_arm_vcsuspend(state);
2414 		}
2415 	} else
2416 		vchiq_log_trace(vchiq_susp_log_level,
2417 			"%s %s count %d, state count %d",
2418 			__func__, entity, *entity_uc,
2419 			arm_state->videocore_use_count);
2420 
2421 unlock:
2422 	write_unlock_bh(&arm_state->susp_res_lock);
2423 
2424 out:
2425 	vchiq_log_trace(vchiq_susp_log_level, "%s exit %d", __func__, ret);
2426 	return ret;
2427 }
2428 
2429 void
2430 vchiq_on_remote_use(VCHIQ_STATE_T *state)
2431 {
2432 	VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
2433 	vchiq_log_trace(vchiq_susp_log_level, "%s", __func__);
2434 	atomic_inc(&arm_state->ka_use_count);
2435 	complete(&arm_state->ka_evt);
2436 }
2437 
2438 void
2439 vchiq_on_remote_release(VCHIQ_STATE_T *state)
2440 {
2441 	VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
2442 	vchiq_log_trace(vchiq_susp_log_level, "%s", __func__);
2443 	atomic_inc(&arm_state->ka_release_count);
2444 	complete(&arm_state->ka_evt);
2445 }
2446 
2447 VCHIQ_STATUS_T
2448 vchiq_use_service_internal(VCHIQ_SERVICE_T *service)
2449 {
2450 	return vchiq_use_internal(service->state, service, USE_TYPE_SERVICE);
2451 }
2452 
2453 VCHIQ_STATUS_T
2454 vchiq_release_service_internal(VCHIQ_SERVICE_T *service)
2455 {
2456 	return vchiq_release_internal(service->state, service);
2457 }
2458 
2459 static void suspend_timer_callback(unsigned long context)
2460 {
2461 	VCHIQ_STATE_T *state = (VCHIQ_STATE_T *)context;
2462 	VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
2463 	if (!arm_state)
2464 		goto out;
2465 	vchiq_log_info(vchiq_susp_log_level,
2466 		"%s - suspend timer expired - check suspend", __func__);
2467 	vchiq_check_suspend(state);
2468 out:
2469 	return;
2470 }
2471 
2472 VCHIQ_STATUS_T
2473 vchiq_use_service_no_resume(VCHIQ_SERVICE_HANDLE_T handle)
2474 {
2475 	VCHIQ_STATUS_T ret = VCHIQ_ERROR;
2476 	VCHIQ_SERVICE_T *service = find_service_by_handle(handle);
2477 	if (service) {
2478 		ret = vchiq_use_internal(service->state, service,
2479 				USE_TYPE_SERVICE_NO_RESUME);
2480 		unlock_service(service);
2481 	}
2482 	return ret;
2483 }
2484 
2485 VCHIQ_STATUS_T
2486 vchiq_use_service(VCHIQ_SERVICE_HANDLE_T handle)
2487 {
2488 	VCHIQ_STATUS_T ret = VCHIQ_ERROR;
2489 	VCHIQ_SERVICE_T *service = find_service_by_handle(handle);
2490 	if (service) {
2491 		ret = vchiq_use_internal(service->state, service,
2492 				USE_TYPE_SERVICE);
2493 		unlock_service(service);
2494 	}
2495 	return ret;
2496 }
2497 
2498 VCHIQ_STATUS_T
2499 vchiq_release_service(VCHIQ_SERVICE_HANDLE_T handle)
2500 {
2501 	VCHIQ_STATUS_T ret = VCHIQ_ERROR;
2502 	VCHIQ_SERVICE_T *service = find_service_by_handle(handle);
2503 	if (service) {
2504 		ret = vchiq_release_internal(service->state, service);
2505 		unlock_service(service);
2506 	}
2507 	return ret;
2508 }
2509 
2510 void
2511 vchiq_dump_service_use_state(VCHIQ_STATE_T *state)
2512 {
2513 	VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
2514 	int i, j = 0;
2515 	/* Only dump 64 services */
2516 	static const int local_max_services = 64;
2517 	/* If there's more than 64 services, only dump ones with
2518 	 * non-zero counts */
2519 	int only_nonzero = 0;
2520 	static const char *nz = "<-- preventing suspend";
2521 
2522 	enum vc_suspend_status vc_suspend_state;
2523 	enum vc_resume_status  vc_resume_state;
2524 	int peer_count;
2525 	int vc_use_count;
2526 	int active_services;
2527 	struct service_data_struct {
2528 		int fourcc;
2529 		int clientid;
2530 		int use_count;
2531 	} service_data[local_max_services];
2532 
2533 	if (!arm_state)
2534 		return;
2535 
2536 	read_lock_bh(&arm_state->susp_res_lock);
2537 	vc_suspend_state = arm_state->vc_suspend_state;
2538 	vc_resume_state  = arm_state->vc_resume_state;
2539 	peer_count = arm_state->peer_use_count;
2540 	vc_use_count = arm_state->videocore_use_count;
2541 	active_services = state->unused_service;
2542 	if (active_services > local_max_services)
2543 		only_nonzero = 1;
2544 
2545 	for (i = 0; (i < active_services) && (j < local_max_services); i++) {
2546 		VCHIQ_SERVICE_T *service_ptr = state->services[i];
2547 		if (!service_ptr)
2548 			continue;
2549 
2550 		if (only_nonzero && !service_ptr->service_use_count)
2551 			continue;
2552 
2553 		if (service_ptr->srvstate != VCHIQ_SRVSTATE_FREE) {
2554 			service_data[j].fourcc = service_ptr->base.fourcc;
2555 			service_data[j].clientid = service_ptr->client_id;
2556 			service_data[j++].use_count = service_ptr->
2557 							service_use_count;
2558 		}
2559 	}
2560 
2561 	read_unlock_bh(&arm_state->susp_res_lock);
2562 
2563 	vchiq_log_warning(vchiq_susp_log_level,
2564 		"-- Videcore suspend state: %s --",
2565 		suspend_state_names[vc_suspend_state + VC_SUSPEND_NUM_OFFSET]);
2566 	vchiq_log_warning(vchiq_susp_log_level,
2567 		"-- Videcore resume state: %s --",
2568 		resume_state_names[vc_resume_state + VC_RESUME_NUM_OFFSET]);
2569 
2570 	if (only_nonzero)
2571 		vchiq_log_warning(vchiq_susp_log_level, "Too many active "
2572 			"services (%d).  Only dumping up to first %d services "
2573 			"with non-zero use-count", active_services,
2574 			local_max_services);
2575 
2576 	for (i = 0; i < j; i++) {
2577 		vchiq_log_warning(vchiq_susp_log_level,
2578 			"----- %c%c%c%c:%d service count %d %s",
2579 			VCHIQ_FOURCC_AS_4CHARS(service_data[i].fourcc),
2580 			service_data[i].clientid,
2581 			service_data[i].use_count,
2582 			service_data[i].use_count ? nz : "");
2583 	}
2584 	vchiq_log_warning(vchiq_susp_log_level,
2585 		"----- VCHIQ use count count %d", peer_count);
2586 	vchiq_log_warning(vchiq_susp_log_level,
2587 		"--- Overall vchiq instance use count %d", vc_use_count);
2588 
2589 	vchiq_dump_platform_use_state(state);
2590 }
2591 
2592 VCHIQ_STATUS_T
2593 vchiq_check_service(VCHIQ_SERVICE_T *service)
2594 {
2595 	VCHIQ_ARM_STATE_T *arm_state;
2596 	VCHIQ_STATUS_T ret = VCHIQ_ERROR;
2597 
2598 	if (!service || !service->state)
2599 		goto out;
2600 
2601 	vchiq_log_trace(vchiq_susp_log_level, "%s", __func__);
2602 
2603 	arm_state = vchiq_platform_get_arm_state(service->state);
2604 
2605 	read_lock_bh(&arm_state->susp_res_lock);
2606 	if (service->service_use_count)
2607 		ret = VCHIQ_SUCCESS;
2608 	read_unlock_bh(&arm_state->susp_res_lock);
2609 
2610 	if (ret == VCHIQ_ERROR) {
2611 		vchiq_log_error(vchiq_susp_log_level,
2612 			"%s ERROR - %c%c%c%c:%8x service count %d, "
2613 			"state count %d, videocore suspend state %s", __func__,
2614 			VCHIQ_FOURCC_AS_4CHARS(service->base.fourcc),
2615 			service->client_id, service->service_use_count,
2616 			arm_state->videocore_use_count,
2617 			suspend_state_names[arm_state->vc_suspend_state +
2618 						VC_SUSPEND_NUM_OFFSET]);
2619 		vchiq_dump_service_use_state(service->state);
2620 	}
2621 out:
2622 	return ret;
2623 }
2624 
2625 /* stub functions */
2626 void vchiq_on_remote_use_active(VCHIQ_STATE_T *state)
2627 {
2628 	(void)state;
2629 }
2630 
2631 void vchiq_platform_conn_state_changed(VCHIQ_STATE_T *state,
2632 	VCHIQ_CONNSTATE_T oldstate, VCHIQ_CONNSTATE_T newstate)
2633 {
2634 	VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
2635 	vchiq_log_info(vchiq_susp_log_level, "%d: %s->%s", state->id,
2636 		get_conn_state_name(oldstate), get_conn_state_name(newstate));
2637 	if (state->conn_state == VCHIQ_CONNSTATE_CONNECTED) {
2638 		write_lock_bh(&arm_state->susp_res_lock);
2639 		if (!arm_state->first_connect) {
2640 			char threadname[10];
2641 			arm_state->first_connect = 1;
2642 			write_unlock_bh(&arm_state->susp_res_lock);
2643 			snprintf(threadname, sizeof(threadname), "VCHIQka-%d",
2644 				state->id);
2645 			arm_state->ka_thread = vchiq_thread_create(
2646 				&vchiq_keepalive_thread_func,
2647 				(void *)state,
2648 				threadname);
2649 			if (arm_state->ka_thread == NULL) {
2650 				vchiq_log_error(vchiq_susp_log_level,
2651 					"vchiq: FATAL: couldn't create thread %s",
2652 					threadname);
2653 			} else {
2654 				wake_up_process(arm_state->ka_thread);
2655 			}
2656 		} else
2657 			write_unlock_bh(&arm_state->susp_res_lock);
2658 	}
2659 }
2660 
2661 /****************************************************************************
2662 *
2663 *   vchiq_init - called when the module is loaded.
2664 *
2665 ***************************************************************************/
2666 
2667 int __init vchiq_init(void);
2668 int __init
2669 vchiq_init(void)
2670 {
2671 	int err;
2672 
2673 #ifdef notyet
2674 	/* create proc entries */
2675 	err = vchiq_proc_init();
2676 	if (err != 0)
2677 		goto failed_proc_init;
2678 #endif
2679 
2680 	spin_lock_init(&msg_queue_spinlock);
2681 
2682 	err = vchiq_platform_init(&g_state);
2683 	if (err != 0)
2684 		goto failed_platform_init;
2685 
2686 	vchiq_log_info(vchiq_arm_log_level,
2687 		"vchiq: initialised - version %d (min %d)",
2688 		VCHIQ_VERSION, VCHIQ_VERSION_MIN);
2689 
2690 	return 0;
2691 
2692 failed_platform_init:
2693 	vchiq_log_warning(vchiq_arm_log_level, "could not load vchiq");
2694 	return err;
2695 }
2696 
2697 #ifdef notyet
2698 static int vchiq_instance_get_use_count(VCHIQ_INSTANCE_T instance)
2699 {
2700 	VCHIQ_SERVICE_T *service;
2701 	int use_count = 0, i;
2702 	i = 0;
2703 	while ((service = next_service_by_instance(instance->state,
2704 		instance, &i)) != NULL) {
2705 		use_count += service->service_use_count;
2706 		unlock_service(service);
2707 	}
2708 	return use_count;
2709 }
2710 
2711 /* read the per-process use-count */
2712 static int proc_read_use_count(char *page, char **start,
2713 			       off_t off, int count,
2714 			       int *eof, void *data)
2715 {
2716 	VCHIQ_INSTANCE_T instance = data;
2717 	int len, use_count;
2718 
2719 	use_count = vchiq_instance_get_use_count(instance);
2720 	len = snprintf(page+off, count, "%d\n", use_count);
2721 
2722 	return len;
2723 }
2724 
2725 /* add an instance (process) to the proc entries */
2726 static int vchiq_proc_add_instance(VCHIQ_INSTANCE_T instance)
2727 {
2728 	char pidstr[32];
2729 	struct proc_dir_entry *top, *use_count;
2730 	struct proc_dir_entry *clients = vchiq_clients_top();
2731 	int pid = instance->pid;
2732 
2733 	snprintf(pidstr, sizeof(pidstr), "%d", pid);
2734 	top = proc_mkdir(pidstr, clients);
2735 	if (!top)
2736 		goto fail_top;
2737 
2738 	use_count = create_proc_read_entry("use_count",
2739 					   0444, top,
2740 					   proc_read_use_count,
2741 					   instance);
2742 	if (!use_count)
2743 		goto fail_use_count;
2744 
2745 	instance->proc_entry = top;
2746 
2747 	return 0;
2748 
2749 fail_use_count:
2750 	remove_proc_entry(top->name, clients);
2751 fail_top:
2752 	return -ENOMEM;
2753 }
2754 
2755 static void vchiq_proc_remove_instance(VCHIQ_INSTANCE_T instance)
2756 {
2757 	struct proc_dir_entry *clients = vchiq_clients_top();
2758 	remove_proc_entry("use_count", instance->proc_entry);
2759 	remove_proc_entry(instance->proc_entry->name, clients);
2760 }
2761 
2762 #endif
2763 
2764 /****************************************************************************
2765 *
2766 *   vchiq_exit - called when the module is unloaded.
2767 *
2768 ***************************************************************************/
2769 
2770 void vchiq_exit(void);
2771 void
2772 vchiq_exit(void)
2773 {
2774 	vchiq_platform_exit(&g_state);
2775 }
2776