xref: /netbsd-src/sys/external/bsd/vchiq/dist/interface/vchiq_arm/vchiq_arm.c (revision 413d532bcc3f62d122e56d92e13ac64825a40baf)
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 
40 #include "vchiq_core.h"
41 #include "vchiq_ioctl.h"
42 #include "vchiq_arm.h"
43 
44 #define DEVICE_NAME "vchiq"
45 
46 /* Override the default prefix, which would be vchiq_arm (from the filename) */
47 #undef MODULE_PARAM_PREFIX
48 #define MODULE_PARAM_PREFIX DEVICE_NAME "."
49 
50 #define VCHIQ_MINOR 0
51 
52 /* Some per-instance constants */
53 #define MAX_COMPLETIONS 16
54 #define MAX_SERVICES 64
55 #define MAX_ELEMENTS 8
56 #define MSG_QUEUE_SIZE 64
57 
58 #define KEEPALIVE_VER 1
59 #define KEEPALIVE_VER_MIN KEEPALIVE_VER
60 
61 MALLOC_DEFINE(M_VCHIQ, "vchiq_cdev", "VideoCore cdev memory");
62 
63 /* Run time control of log level, based on KERN_XXX level. */
64 int vchiq_arm_log_level = VCHIQ_LOG_DEFAULT;
65 int vchiq_susp_log_level = VCHIQ_LOG_ERROR;
66 
67 #define SUSPEND_TIMER_TIMEOUT_MS 100
68 #define SUSPEND_RETRY_TIMER_TIMEOUT_MS 1000
69 
70 #define VC_SUSPEND_NUM_OFFSET 3 /* number of values before idle which are -ve */
71 static const char *const suspend_state_names[] = {
72 	"VC_SUSPEND_FORCE_CANCELED",
73 	"VC_SUSPEND_REJECTED",
74 	"VC_SUSPEND_FAILED",
75 	"VC_SUSPEND_IDLE",
76 	"VC_SUSPEND_REQUESTED",
77 	"VC_SUSPEND_IN_PROGRESS",
78 	"VC_SUSPEND_SUSPENDED"
79 };
80 #define VC_RESUME_NUM_OFFSET 1 /* number of values before idle which are -ve */
81 static const char *const resume_state_names[] = {
82 	"VC_RESUME_FAILED",
83 	"VC_RESUME_IDLE",
84 	"VC_RESUME_REQUESTED",
85 	"VC_RESUME_IN_PROGRESS",
86 	"VC_RESUME_RESUMED"
87 };
88 /* The number of times we allow force suspend to timeout before actually
89 ** _forcing_ suspend.  This is to cater for SW which fails to release vchiq
90 ** correctly - we don't want to prevent ARM suspend indefinitely in this case.
91 */
92 #define FORCE_SUSPEND_FAIL_MAX 8
93 
94 /* The time in ms allowed for videocore to go idle when force suspend has been
95  * requested */
96 #define FORCE_SUSPEND_TIMEOUT_MS 200
97 
98 
99 static void suspend_timer_callback(unsigned long context);
100 #ifdef notyet
101 static int vchiq_proc_add_instance(VCHIQ_INSTANCE_T instance);
102 static void vchiq_proc_remove_instance(VCHIQ_INSTANCE_T instance);
103 #endif
104 
105 
106 typedef struct user_service_struct {
107 	VCHIQ_SERVICE_T *service;
108 	void *userdata;
109 	VCHIQ_INSTANCE_T instance;
110 	int is_vchi;
111 	int dequeue_pending;
112 	int message_available_pos;
113 	int msg_insert;
114 	int msg_remove;
115 	struct semaphore insert_event;
116 	struct semaphore remove_event;
117 	VCHIQ_HEADER_T * msg_queue[MSG_QUEUE_SIZE];
118 } USER_SERVICE_T;
119 
120 struct bulk_waiter_node {
121 	struct bulk_waiter bulk_waiter;
122 	struct lwp *l;
123 	struct list_head list;
124 };
125 
126 struct vchiq_instance_struct {
127 	VCHIQ_STATE_T *state;
128 	VCHIQ_COMPLETION_DATA_T completions[MAX_COMPLETIONS];
129 	int completion_insert;
130 	int completion_remove;
131 	struct semaphore insert_event;
132 	struct semaphore remove_event;
133 	struct mutex completion_mutex;
134 
135 	int connected;
136 	int closing;
137 	struct lwp *l;
138 	int mark;
139 
140 	struct list_head bulk_waiter_list;
141 	struct mutex bulk_waiter_list_mutex;
142 
143 	struct proc_dir_entry *proc_entry;
144 };
145 
146 typedef struct dump_context_struct {
147 	char __user *buf;
148 	size_t actual;
149 	size_t space;
150 	loff_t offset;
151 } DUMP_CONTEXT_T;
152 
153 VCHIQ_STATE_T g_state;
154 static DEFINE_SPINLOCK(msg_queue_spinlock);
155 
156 static const char *const ioctl_names[] = {
157 	"CONNECT",
158 	"SHUTDOWN",
159 	"CREATE_SERVICE",
160 	"REMOVE_SERVICE",
161 	"QUEUE_MESSAGE",
162 	"QUEUE_BULK_TRANSMIT",
163 	"QUEUE_BULK_RECEIVE",
164 	"AWAIT_COMPLETION",
165 	"DEQUEUE_MESSAGE",
166 	"GET_CLIENT_ID",
167 	"GET_CONFIG",
168 	"CLOSE_SERVICE",
169 	"USE_SERVICE",
170 	"RELEASE_SERVICE",
171 	"SET_SERVICE_OPTION",
172 	"DUMP_PHYS_MEM"
173 };
174 
175 vchiq_static_assert((sizeof(ioctl_names)/sizeof(ioctl_names[0])) ==
176 	(VCHIQ_IOC_MAX + 1));
177 
178 static dev_type_open(vchiq_open);
179 
180 struct cdevsw vchiq_cdevsw = {
181 	.d_open = vchiq_open,
182 	.d_close = noclose,
183 	.d_read = noread,
184 	.d_write = nowrite,
185 	.d_ioctl = noioctl,
186 	.d_stop = nostop,
187 	.d_tty = notty,
188 	.d_poll = nopoll,
189 	.d_mmap = nommap,
190 	.d_kqfilter = nokqfilter,
191 	.d_flag = D_OTHER | D_MPSAFE
192 };
193 
194 extern struct cfdriver vchiq_cd;
195 
196 static int	vchiq_ioctl(struct file *, u_long, void *);
197 static int	vchiq_close(struct file *);
198 
199 static const struct fileops vchiq_fileops = {
200 	.fo_read = fbadop_read,
201 	.fo_write = fbadop_write,
202 	.fo_ioctl = vchiq_ioctl,
203 	.fo_fcntl = fnullop_fcntl,
204 	.fo_poll = fnullop_poll,
205 	.fo_stat = fbadop_stat,
206 	.fo_close = vchiq_close,
207 	.fo_kqfilter = fnullop_kqfilter,
208 };
209 
210 #if 0
211 static void
212 dump_phys_mem(void *virt_addr, uint32_t num_bytes);
213 #endif
214 
215 /****************************************************************************
216 *
217 *   add_completion
218 *
219 ***************************************************************************/
220 
221 static VCHIQ_STATUS_T
222 add_completion(VCHIQ_INSTANCE_T instance, VCHIQ_REASON_T reason,
223 	VCHIQ_HEADER_T *header, USER_SERVICE_T *user_service,
224 	void *bulk_userdata)
225 {
226 	VCHIQ_COMPLETION_DATA_T *completion;
227 	DEBUG_INITIALISE(g_state.local)
228 
229 	while (instance->completion_insert ==
230 		(instance->completion_remove + MAX_COMPLETIONS)) {
231 		/* Out of space - wait for the client */
232 		DEBUG_TRACE(SERVICE_CALLBACK_LINE);
233 		vchiq_log_trace(vchiq_arm_log_level,
234 			"add_completion - completion queue full");
235 		DEBUG_COUNT(COMPLETION_QUEUE_FULL_COUNT);
236 		if (down_interruptible(&instance->remove_event) != 0) {
237 			vchiq_log_info(vchiq_arm_log_level,
238 				"service_callback interrupted");
239 			return VCHIQ_RETRY;
240 		} else if (instance->closing) {
241 			vchiq_log_info(vchiq_arm_log_level,
242 				"service_callback closing");
243 			return VCHIQ_ERROR;
244 		}
245 		DEBUG_TRACE(SERVICE_CALLBACK_LINE);
246 	}
247 
248 	completion =
249 		 &instance->completions[instance->completion_insert &
250 		 (MAX_COMPLETIONS - 1)];
251 
252 	completion->header = header;
253 	completion->reason = reason;
254 	/* N.B. service_userdata is updated while processing AWAIT_COMPLETION */
255 	completion->service_userdata = user_service->service;
256 	completion->bulk_userdata = bulk_userdata;
257 
258 	if (reason == VCHIQ_SERVICE_CLOSED)
259 		/* Take an extra reference, to be held until
260 		   this CLOSED notification is delivered. */
261 		lock_service(user_service->service);
262 
263 	/* A write barrier is needed here to ensure that the entire completion
264 		record is written out before the insert point. */
265 	wmb();
266 
267 	if (reason == VCHIQ_MESSAGE_AVAILABLE)
268 		user_service->message_available_pos =
269 			instance->completion_insert;
270 	instance->completion_insert++;
271 
272 	up(&instance->insert_event);
273 
274 	return VCHIQ_SUCCESS;
275 }
276 
277 /****************************************************************************
278 *
279 *   service_callback
280 *
281 ***************************************************************************/
282 
283 static VCHIQ_STATUS_T
284 service_callback(VCHIQ_REASON_T reason, VCHIQ_HEADER_T *header,
285 	VCHIQ_SERVICE_HANDLE_T handle, void *bulk_userdata)
286 {
287 	/* How do we ensure the callback goes to the right client?
288 	** The service_user data points to a USER_SERVICE_T record containing
289 	** the original callback and the user state structure, which contains a
290 	** circular buffer for completion records.
291 	*/
292 	USER_SERVICE_T *user_service;
293 	VCHIQ_SERVICE_T *service;
294 	VCHIQ_INSTANCE_T instance;
295 	DEBUG_INITIALISE(g_state.local)
296 
297 	DEBUG_TRACE(SERVICE_CALLBACK_LINE);
298 
299 	service = handle_to_service(handle);
300 	BUG_ON(!service);
301 	user_service = (USER_SERVICE_T *)service->base.userdata;
302 	instance = user_service->instance;
303 
304 	if (!instance || instance->closing)
305 		return VCHIQ_SUCCESS;
306 
307 	vchiq_log_trace(vchiq_arm_log_level,
308 		"service_callback - service %lx(%d), handle %x, reason %d, header %lx, "
309 		"instance %lx, bulk_userdata %lx",
310 		(unsigned long)user_service,
311 		service->localport, service->handle,
312 		reason, (unsigned long)header,
313 		(unsigned long)instance, (unsigned long)bulk_userdata);
314 
315 	if (header && user_service->is_vchi) {
316 		spin_lock(&msg_queue_spinlock);
317 		while (user_service->msg_insert ==
318 			(user_service->msg_remove + MSG_QUEUE_SIZE)) {
319 			spin_unlock(&msg_queue_spinlock);
320 			DEBUG_TRACE(SERVICE_CALLBACK_LINE);
321 			DEBUG_COUNT(MSG_QUEUE_FULL_COUNT);
322 			vchiq_log_trace(vchiq_arm_log_level,
323 				"service_callback - msg queue full");
324 			/* If there is no MESSAGE_AVAILABLE in the completion
325 			** queue, add one
326 			*/
327 			if ((user_service->message_available_pos -
328 				instance->completion_remove) < 0) {
329 				VCHIQ_STATUS_T status;
330 				vchiq_log_info(vchiq_arm_log_level,
331 					"Inserting extra MESSAGE_AVAILABLE");
332 				DEBUG_TRACE(SERVICE_CALLBACK_LINE);
333 				status = add_completion(instance, reason,
334 					NULL, user_service, bulk_userdata);
335 				if (status != VCHIQ_SUCCESS) {
336 					DEBUG_TRACE(SERVICE_CALLBACK_LINE);
337 					return status;
338 				}
339 			}
340 
341 			DEBUG_TRACE(SERVICE_CALLBACK_LINE);
342 			if (down_interruptible(&user_service->remove_event)
343 				!= 0) {
344 				vchiq_log_info(vchiq_arm_log_level,
345 					"service_callback interrupted");
346 				DEBUG_TRACE(SERVICE_CALLBACK_LINE);
347 				return VCHIQ_RETRY;
348 			} else if (instance->closing) {
349 				vchiq_log_info(vchiq_arm_log_level,
350 					"service_callback closing");
351 				DEBUG_TRACE(SERVICE_CALLBACK_LINE);
352 				return VCHIQ_ERROR;
353 			}
354 			DEBUG_TRACE(SERVICE_CALLBACK_LINE);
355 			spin_lock(&msg_queue_spinlock);
356 		}
357 
358 		user_service->msg_queue[user_service->msg_insert &
359 			(MSG_QUEUE_SIZE - 1)] = header;
360 		user_service->msg_insert++;
361 		spin_unlock(&msg_queue_spinlock);
362 
363 		up(&user_service->insert_event);
364 
365 		/* If there is a thread waiting in DEQUEUE_MESSAGE, or if
366 		** there is a MESSAGE_AVAILABLE in the completion queue then
367 		** bypass the completion queue.
368 		*/
369 		if (((user_service->message_available_pos -
370 			instance->completion_remove) >= 0) ||
371 			user_service->dequeue_pending) {
372 			DEBUG_TRACE(SERVICE_CALLBACK_LINE);
373 			user_service->dequeue_pending = 0;
374 			return VCHIQ_SUCCESS;
375 		}
376 
377 		header = NULL;
378 	}
379 	DEBUG_TRACE(SERVICE_CALLBACK_LINE);
380 
381 	return add_completion(instance, reason, header, user_service,
382 		bulk_userdata);
383 }
384 
385 /****************************************************************************
386 *
387 *   user_service_free
388 *
389 ***************************************************************************/
390 static void
391 user_service_free(void *userdata)
392 {
393 	USER_SERVICE_T *user_service = userdata;
394 
395 	_sema_destroy(&user_service->insert_event);
396 	_sema_destroy(&user_service->remove_event);
397 
398 	kfree(user_service);
399 }
400 
401 /****************************************************************************
402 *
403 *   vchiq_ioctl
404 *
405 ***************************************************************************/
406 
407 static int
408 vchiq_ioctl(struct file *fp, u_long cmd, void *arg)
409 {
410 	VCHIQ_INSTANCE_T instance;
411 	VCHIQ_STATUS_T status = VCHIQ_SUCCESS;
412 	VCHIQ_SERVICE_T *service = NULL;
413 	int ret = 0;
414 	int i, rc;
415 	DEBUG_INITIALISE(g_state.local)
416 
417 	instance = fp->f_data;
418 
419 /* XXXBSD: HACK! */
420 #define _IOC_NR(x) ((x) & 0xff)
421 #define	_IOC_TYPE(x)	IOCGROUP(x)
422 
423 	vchiq_log_trace(vchiq_arm_log_level,
424 		 "vchiq_ioctl - instance %x, cmd %s, arg %p",
425 		(unsigned int)instance,
426 		((_IOC_TYPE(cmd) == VCHIQ_IOC_MAGIC) &&
427 		(_IOC_NR(cmd) <= VCHIQ_IOC_MAX)) ?
428 		ioctl_names[_IOC_NR(cmd)] : "<invalid>", arg);
429 
430 	switch (cmd) {
431 	case VCHIQ_IOC_SHUTDOWN:
432 		if (!instance->connected)
433 			break;
434 
435 		/* Remove all services */
436 		i = 0;
437 		while ((service = next_service_by_instance(instance->state,
438 			instance, &i)) != NULL) {
439 			status = vchiq_remove_service(service->handle);
440 			unlock_service(service);
441 			if (status != VCHIQ_SUCCESS)
442 				break;
443 		}
444 		service = NULL;
445 
446 		if (status == VCHIQ_SUCCESS) {
447 			/* Wake the completion thread and ask it to exit */
448 			instance->closing = 1;
449 			up(&instance->insert_event);
450 		}
451 
452 		break;
453 
454 	case VCHIQ_IOC_CONNECT:
455 		if (instance->connected) {
456 			ret = -EINVAL;
457 			break;
458 		}
459 		rc = lmutex_lock_interruptible(&instance->state->mutex);
460 		if (rc != 0) {
461 			vchiq_log_error(vchiq_arm_log_level,
462 				"vchiq: connect: could not lock mutex for "
463 				"state %d: %d",
464 				instance->state->id, rc);
465 			ret = -EINTR;
466 			break;
467 		}
468 		status = vchiq_connect_internal(instance->state, instance);
469 		lmutex_unlock(&instance->state->mutex);
470 
471 		if (status == VCHIQ_SUCCESS)
472 			instance->connected = 1;
473 		else
474 			vchiq_log_error(vchiq_arm_log_level,
475 				"vchiq: could not connect: %d", status);
476 		break;
477 
478 	case VCHIQ_IOC_CREATE_SERVICE: {
479 		VCHIQ_CREATE_SERVICE_T *pargs = arg;
480 		USER_SERVICE_T *user_service = NULL;
481 		void *userdata;
482 		int srvstate;
483 
484 		user_service = kzalloc(sizeof(USER_SERVICE_T), GFP_KERNEL);
485 		if (!user_service) {
486 			ret = -ENOMEM;
487 			break;
488 		}
489 
490 		if (pargs->is_open) {
491 			if (!instance->connected) {
492 				ret = -ENOTCONN;
493 				kfree(user_service);
494 				break;
495 			}
496 			srvstate = VCHIQ_SRVSTATE_OPENING;
497 		} else {
498 			srvstate =
499 				 instance->connected ?
500 				 VCHIQ_SRVSTATE_LISTENING :
501 				 VCHIQ_SRVSTATE_HIDDEN;
502 		}
503 
504 		userdata = pargs->params.userdata;
505 		pargs->params.callback = service_callback;
506 		pargs->params.userdata = user_service;
507 		service = vchiq_add_service_internal(
508 				instance->state,
509 				&pargs->params, srvstate,
510 				instance, user_service_free);
511 
512 		if (service != NULL) {
513 			user_service->service = service;
514 			user_service->userdata = userdata;
515 			user_service->instance = instance;
516 			user_service->is_vchi = pargs->is_vchi;
517 			user_service->dequeue_pending = 0;
518 			user_service->message_available_pos =
519 				instance->completion_remove - 1;
520 			user_service->msg_insert = 0;
521 			user_service->msg_remove = 0;
522 			_sema_init(&user_service->insert_event, 0);
523 			_sema_init(&user_service->remove_event, 0);
524 
525 			if (pargs->is_open) {
526 				status = vchiq_open_service_internal
527 					(service, (uintptr_t)instance->l);
528 				if (status != VCHIQ_SUCCESS) {
529 					vchiq_remove_service(service->handle);
530 					service = NULL;
531 					ret = (status == VCHIQ_RETRY) ?
532 						-EINTR : -EIO;
533 					break;
534 				}
535 			}
536 
537 #ifdef VCHIQ_IOCTL_DEBUG
538 			printf("%s: [CREATE SERVICE] handle = %08x\n", __func__, service->handle);
539 #endif
540 			pargs->handle = service->handle;
541 
542 			service = NULL;
543 		} else {
544 			ret = -EEXIST;
545 			kfree(user_service);
546 		}
547 	} break;
548 
549 	case VCHIQ_IOC_CLOSE_SERVICE: {
550 		VCHIQ_SERVICE_HANDLE_T handle = *(VCHIQ_SERVICE_HANDLE_T *)arg;
551 
552 #ifdef VCHIQ_IOCTL_DEBUG
553 		printf("%s: [CLOSE SERVICE] handle = %08x\n", __func__, handle);
554 #endif
555 
556 		service = find_service_for_instance(instance, handle);
557 		if (service != NULL)
558 			status = vchiq_close_service(service->handle);
559 		else
560 			ret = -EINVAL;
561 	} break;
562 
563 	case VCHIQ_IOC_REMOVE_SERVICE: {
564 		VCHIQ_SERVICE_HANDLE_T handle = *(VCHIQ_SERVICE_HANDLE_T *)arg;
565 
566 #ifdef VCHIQ_IOCTL_DEBUG
567 		printf("%s: [REMOVE SERVICE] handle = %08x\n", __func__, handle);
568 #endif
569 
570 		service = find_service_for_instance(instance, handle);
571 		if (service != NULL)
572 			status = vchiq_remove_service(service->handle);
573 		else
574 			ret = -EINVAL;
575 	} break;
576 
577 	case VCHIQ_IOC_USE_SERVICE:
578 	case VCHIQ_IOC_RELEASE_SERVICE:	{
579 		VCHIQ_SERVICE_HANDLE_T handle = *(VCHIQ_SERVICE_HANDLE_T *)arg;
580 
581 #ifdef VCHIQ_IOCTL_DEBUG
582 		printf("%s: [%s SERVICE] handle = %08x\n", __func__,
583 		    cmd == VCHIQ_IOC_USE_SERVICE ? "USE" : "RELEASE", handle);
584 #endif
585 
586 		service = find_service_for_instance(instance, handle);
587 		if (service != NULL) {
588 			status = (cmd == VCHIQ_IOC_USE_SERVICE)	?
589 				vchiq_use_service_internal(service) :
590 				vchiq_release_service_internal(service);
591 			if (status != VCHIQ_SUCCESS) {
592 				vchiq_log_error(vchiq_susp_log_level,
593 					"%s: cmd %s returned error %d for "
594 					"service %c%c%c%c:%8x",
595 					__func__,
596 					(cmd == VCHIQ_IOC_USE_SERVICE) ?
597 						"VCHIQ_IOC_USE_SERVICE" :
598 						"VCHIQ_IOC_RELEASE_SERVICE",
599 					status,
600 					VCHIQ_FOURCC_AS_4CHARS(
601 						service->base.fourcc),
602 					service->client_id);
603 				ret = -EINVAL;
604 			}
605 		} else
606 			ret = -EINVAL;
607 	} break;
608 
609 	case VCHIQ_IOC_QUEUE_MESSAGE: {
610 		VCHIQ_QUEUE_MESSAGE_T *pargs = arg;
611 
612 #ifdef VCHIQ_IOCTL_DEBUG
613 		printf("%s: [QUEUE MESSAGE] handle = %08x\n", __func__, pargs->handle);
614 #endif
615 
616 		service = find_service_for_instance(instance, pargs->handle);
617 
618 		if ((service != NULL) && (pargs->count <= MAX_ELEMENTS)) {
619 			/* Copy elements into kernel space */
620 			VCHIQ_ELEMENT_T elements[MAX_ELEMENTS];
621 			if (copy_from_user(elements, pargs->elements,
622 				pargs->count * sizeof(VCHIQ_ELEMENT_T)) == 0)
623 				status = vchiq_queue_message
624 					(pargs->handle,
625 					elements, pargs->count);
626 			else
627 				ret = -EFAULT;
628 		} else {
629 			ret = -EINVAL;
630 		}
631 	} break;
632 
633 	case VCHIQ_IOC_QUEUE_BULK_TRANSMIT:
634 	case VCHIQ_IOC_QUEUE_BULK_RECEIVE: {
635 		VCHIQ_QUEUE_BULK_TRANSFER_T *pargs = arg;
636 		struct bulk_waiter_node *waiter = NULL;
637 		VCHIQ_BULK_DIR_T dir =
638 			(cmd == VCHIQ_IOC_QUEUE_BULK_TRANSMIT) ?
639 			VCHIQ_BULK_TRANSMIT : VCHIQ_BULK_RECEIVE;
640 
641 		service = find_service_for_instance(instance, pargs->handle);
642 		if (!service) {
643 			ret = -EINVAL;
644 			break;
645 		}
646 
647 		if (pargs->mode == VCHIQ_BULK_MODE_BLOCKING) {
648 			waiter = kzalloc(sizeof(struct bulk_waiter_node),
649 				GFP_KERNEL);
650 			if (!waiter) {
651 				ret = -ENOMEM;
652 				break;
653 			}
654 			pargs->userdata = &waiter->bulk_waiter;
655 		} else if (pargs->mode == VCHIQ_BULK_MODE_WAITING) {
656 			struct list_head *pos;
657 			lmutex_lock(&instance->bulk_waiter_list_mutex);
658 			list_for_each(pos, &instance->bulk_waiter_list) {
659 				if (list_entry(pos, struct bulk_waiter_node,
660 					list)->l == current) {
661 					waiter = list_entry(pos,
662 						struct bulk_waiter_node,
663 						list);
664 					list_del(pos);
665 					break;
666 				}
667 
668 			}
669 			lmutex_unlock(&instance->bulk_waiter_list_mutex);
670 			if (!waiter) {
671 				vchiq_log_error(vchiq_arm_log_level,
672 					"no bulk_waiter found for lwp %p",
673 					current);
674 				ret = -ESRCH;
675 				break;
676 			}
677 			vchiq_log_info(vchiq_arm_log_level,
678 				"found bulk_waiter %x for lwp %p",
679 				(unsigned int)waiter, current);
680 			pargs->userdata = &waiter->bulk_waiter;
681 		}
682 		status = vchiq_bulk_transfer
683 			(pargs->handle,
684 			 VCHI_MEM_HANDLE_INVALID,
685 			 pargs->data, pargs->size,
686 			 pargs->userdata, pargs->mode,
687 			 dir);
688 		if (!waiter)
689 			break;
690 		if ((status != VCHIQ_RETRY) || fatal_signal_pending(current) ||
691 			!waiter->bulk_waiter.bulk) {
692 			if (waiter->bulk_waiter.bulk) {
693 				/* Cancel the signal when the transfer
694 				** completes. */
695 				spin_lock(&bulk_waiter_spinlock);
696 				waiter->bulk_waiter.bulk->userdata = NULL;
697 				spin_unlock(&bulk_waiter_spinlock);
698 			}
699 			_sema_destroy(&waiter->bulk_waiter.event);
700 			kfree(waiter);
701 		} else {
702 			const VCHIQ_BULK_MODE_T mode_waiting =
703 				VCHIQ_BULK_MODE_WAITING;
704 			waiter->l = current;
705 			lmutex_lock(&instance->bulk_waiter_list_mutex);
706 			list_add(&waiter->list, &instance->bulk_waiter_list);
707 			lmutex_unlock(&instance->bulk_waiter_list_mutex);
708 			vchiq_log_info(vchiq_arm_log_level,
709 				"saved bulk_waiter %x for lwp %p",
710 				(unsigned int)waiter, current);
711 
712 			pargs->mode = mode_waiting;
713 		}
714 	} break;
715 
716 	case VCHIQ_IOC_AWAIT_COMPLETION: {
717 		VCHIQ_AWAIT_COMPLETION_T *pargs = arg;
718 
719 		DEBUG_TRACE(AWAIT_COMPLETION_LINE);
720 		if (!instance->connected) {
721 			ret = -ENOTCONN;
722 			break;
723 		}
724 
725 		lmutex_lock(&instance->completion_mutex);
726 
727 		DEBUG_TRACE(AWAIT_COMPLETION_LINE);
728 		while ((instance->completion_remove ==
729 			instance->completion_insert)
730 			&& !instance->closing) {
731 			DEBUG_TRACE(AWAIT_COMPLETION_LINE);
732 			lmutex_unlock(&instance->completion_mutex);
733 			rc = down_interruptible(&instance->insert_event);
734 			lmutex_lock(&instance->completion_mutex);
735 			if (rc != 0) {
736 				DEBUG_TRACE(AWAIT_COMPLETION_LINE);
737 				vchiq_log_info(vchiq_arm_log_level,
738 					"AWAIT_COMPLETION interrupted");
739 				ret = -EINTR;
740 				break;
741 			}
742 		}
743 		DEBUG_TRACE(AWAIT_COMPLETION_LINE);
744 
745 		/* A read memory barrier is needed to stop prefetch of a stale
746 		** completion record
747 		*/
748 		rmb();
749 
750 		if (ret == 0) {
751 			int msgbufcount = pargs->msgbufcount;
752 			int count;
753 
754 			for (count = 0; count < pargs->count; count++) {
755 				VCHIQ_COMPLETION_DATA_T *completion;
756 				VCHIQ_SERVICE_T *service1;
757 				USER_SERVICE_T *user_service;
758 				VCHIQ_HEADER_T *header;
759 				if (instance->completion_remove ==
760 					instance->completion_insert)
761 					break;
762 				completion = &instance->completions[
763 					instance->completion_remove &
764 					(MAX_COMPLETIONS - 1)];
765 
766 				service1 = completion->service_userdata;
767 				user_service = service1->base.userdata;
768 				completion->service_userdata =
769 					user_service->userdata;
770 
771 				header = completion->header;
772 				if (header) {
773 					void __user *msgbuf;
774 					int msglen;
775 
776 					msglen = header->size +
777 						sizeof(VCHIQ_HEADER_T);
778 					/* This must be a VCHIQ-style service */
779 					if (pargs->msgbufsize < msglen) {
780 						vchiq_log_error(
781 							vchiq_arm_log_level,
782 							"header %x: msgbufsize"
783 							" %x < msglen %x",
784 							(unsigned int)header,
785 							pargs->msgbufsize,
786 							msglen);
787 						WARN(1, "invalid message "
788 							"size\n");
789 						if (count == 0)
790 							ret = -EMSGSIZE;
791 						break;
792 					}
793 					if (msgbufcount <= 0)
794 						/* Stall here for lack of a
795 						** buffer for the message. */
796 						break;
797 					/* Get the pointer from user space */
798 					msgbufcount--;
799 					if (copy_from_user(&msgbuf,
800 						(const void __user *)
801 						&pargs->msgbufs[msgbufcount],
802 						sizeof(msgbuf)) != 0) {
803 						if (count == 0)
804 							ret = -EFAULT;
805 						break;
806 					}
807 
808 					/* Copy the message to user space */
809 					if (copy_to_user(msgbuf, header,
810 						msglen) != 0) {
811 						if (count == 0)
812 							ret = -EFAULT;
813 						break;
814 					}
815 
816 					/* Now it has been copied, the message
817 					** can be released. */
818 					vchiq_release_message(service1->handle,
819 						header);
820 
821 					/* The completion must point to the
822 					** msgbuf. */
823 					completion->header = msgbuf;
824 				}
825 
826 				if (completion->reason ==
827 					VCHIQ_SERVICE_CLOSED)
828 					unlock_service(service1);
829 
830 				if (copy_to_user((void __user *)(
831 					(size_t)pargs->buf +
832 					count * sizeof(VCHIQ_COMPLETION_DATA_T)),
833 					completion,
834 					sizeof(VCHIQ_COMPLETION_DATA_T)) != 0) {
835 						if (count == 0)
836 							ret = -EFAULT;
837 					break;
838 				}
839 
840 				instance->completion_remove++;
841 			}
842 
843 			pargs->msgbufcount = msgbufcount;
844 			pargs->count = count;
845 		}
846 
847 		if (ret != 0)
848 			up(&instance->remove_event);
849 		lmutex_unlock(&instance->completion_mutex);
850 		DEBUG_TRACE(AWAIT_COMPLETION_LINE);
851 	} break;
852 
853 	case VCHIQ_IOC_DEQUEUE_MESSAGE: {
854 		VCHIQ_DEQUEUE_MESSAGE_T *pargs = arg;
855 		USER_SERVICE_T *user_service;
856 		VCHIQ_HEADER_T *header;
857 
858 		DEBUG_TRACE(DEQUEUE_MESSAGE_LINE);
859 		service = find_service_for_instance(instance, pargs->handle);
860 		if (!service) {
861 			ret = -EINVAL;
862 			break;
863 		}
864 		user_service = (USER_SERVICE_T *)service->base.userdata;
865 		if (user_service->is_vchi == 0) {
866 			ret = -EINVAL;
867 			break;
868 		}
869 
870 		spin_lock(&msg_queue_spinlock);
871 		if (user_service->msg_remove == user_service->msg_insert) {
872 			if (!pargs->blocking) {
873 				spin_unlock(&msg_queue_spinlock);
874 				DEBUG_TRACE(DEQUEUE_MESSAGE_LINE);
875 				ret = -EWOULDBLOCK;
876 				break;
877 			}
878 			user_service->dequeue_pending = 1;
879 			do {
880 				spin_unlock(&msg_queue_spinlock);
881 				DEBUG_TRACE(DEQUEUE_MESSAGE_LINE);
882 				if (down_interruptible(
883 					&user_service->insert_event) != 0) {
884 					vchiq_log_info(vchiq_arm_log_level,
885 						"DEQUEUE_MESSAGE interrupted");
886 					ret = -EINTR;
887 					break;
888 				}
889 				spin_lock(&msg_queue_spinlock);
890 			} while (user_service->msg_remove ==
891 				user_service->msg_insert);
892 
893 			if (ret)
894 				break;
895 		}
896 
897 		BUG_ON((int)(user_service->msg_insert -
898 			user_service->msg_remove) < 0);
899 
900 		header = user_service->msg_queue[user_service->msg_remove &
901 			(MSG_QUEUE_SIZE - 1)];
902 		user_service->msg_remove++;
903 		spin_unlock(&msg_queue_spinlock);
904 
905 		up(&user_service->remove_event);
906 		if (header == NULL)
907 			ret = -ENOTCONN;
908 		else if (header->size <= pargs->bufsize) {
909 			/* Copy to user space if msgbuf is not NULL */
910 			if ((pargs->buf == NULL) ||
911 				(copy_to_user((void __user *)pargs->buf,
912 				header->data,
913 				header->size) == 0)) {
914 				pargs->bufsize = header->size;
915 				vchiq_release_message(
916 					service->handle,
917 					header);
918 			} else
919 				ret = -EFAULT;
920 		} else {
921 			vchiq_log_error(vchiq_arm_log_level,
922 				"header %x: bufsize %x < size %x",
923 				(unsigned int)header, pargs->bufsize,
924 				header->size);
925 			WARN(1, "invalid size\n");
926 			ret = -EMSGSIZE;
927 		}
928 		DEBUG_TRACE(DEQUEUE_MESSAGE_LINE);
929 	} break;
930 
931 	case VCHIQ_IOC_GET_CLIENT_ID: {
932 		VCHIQ_SERVICE_HANDLE_T handle = (VCHIQ_SERVICE_HANDLE_T)arg;
933 
934 		ret = vchiq_get_client_id(handle);
935 	} break;
936 
937 	case VCHIQ_IOC_GET_CONFIG: {
938 		VCHIQ_GET_CONFIG_T *pargs = arg;
939 		VCHIQ_CONFIG_T config;
940 
941 		if (pargs->config_size > sizeof(config)) {
942 			ret = -EINVAL;
943 			break;
944 		}
945 		status = vchiq_get_config(instance, pargs->config_size, &config);
946 		if (status == VCHIQ_SUCCESS) {
947 			if (copy_to_user((void __user *)pargs->pconfig,
948 				&config, pargs->config_size) != 0) {
949 				ret = -EFAULT;
950 				break;
951 			}
952 		}
953 	} break;
954 
955 	case VCHIQ_IOC_SET_SERVICE_OPTION: {
956 		VCHIQ_SET_SERVICE_OPTION_T *pargs = arg;
957 
958 		service = find_service_for_instance(instance, pargs->handle);
959 		if (!service) {
960 			ret = -EINVAL;
961 			break;
962 		}
963 
964 		status = vchiq_set_service_option(
965 				pargs->handle, pargs->option, pargs->value);
966 	} break;
967 
968 	case VCHIQ_IOC_DUMP_PHYS_MEM: {
969 #if 0
970 		VCHIQ_DUMP_MEM_T *pargs = arg;
971 #endif
972 
973 		printf("IMPLEMENT ME: %s:%d\n", __FILE__, __LINE__);
974 #if 0
975 		dump_phys_mem(pargs->virt_addr, pargs->num_bytes);
976 #endif
977 	} break;
978 
979 	default:
980 		ret = -ENOTTY;
981 		break;
982 	}
983 
984 	if (service)
985 		unlock_service(service);
986 
987 	if (ret == 0) {
988 		if (status == VCHIQ_ERROR)
989 			ret = -EIO;
990 		else if (status == VCHIQ_RETRY)
991 			ret = -EINTR;
992 	}
993 
994 	if ((status == VCHIQ_SUCCESS) && (ret < 0) && (ret != -EINTR) &&
995 		(ret != -EWOULDBLOCK))
996 		vchiq_log_info(vchiq_arm_log_level,
997 			"  ioctl instance %lx, cmd %s -> status %d, %d",
998 			(unsigned long)instance,
999 			(_IOC_NR(cmd) <= VCHIQ_IOC_MAX) ?
1000 				ioctl_names[_IOC_NR(cmd)] :
1001 				"<invalid>",
1002 			status, ret);
1003 	else
1004 		vchiq_log_trace(vchiq_arm_log_level,
1005 			"  ioctl instance %lx, cmd %s -> status %d, %d",
1006 			(unsigned long)instance,
1007 			(_IOC_NR(cmd) <= VCHIQ_IOC_MAX) ?
1008 				ioctl_names[_IOC_NR(cmd)] :
1009 				"<invalid>",
1010 			status, ret);
1011 
1012 	/* XXXBSD: report BSD-style error to userland */
1013 	if (ret < 0)
1014 		ret = -ret;
1015 
1016 	return ret;
1017 }
1018 
1019 #if notyet
1020 static void
1021 instance_dtr(void *data)
1022 {
1023 
1024    free(data, M_VCHIQ);
1025 }
1026 #endif
1027 
1028 /****************************************************************************
1029 *
1030 *   vchiq_open
1031 *
1032 ***************************************************************************/
1033 
1034 static int
1035 vchiq_open(dev_t dev, int flags, int mode, lwp_t *l)
1036 {
1037 	VCHIQ_INSTANCE_T instance = NULL;
1038 	struct file *fp;
1039 	int err, fd;
1040 
1041 	vchiq_log_info(vchiq_arm_log_level, "vchiq_open");
1042 
1043 	/* XXXBSD: do we really need this check? */
1044 	if (device_lookup_private(&vchiq_cd, minor(dev)) != NULL) {
1045 		VCHIQ_STATE_T *state = vchiq_get_state();
1046 
1047 		if (!state) {
1048 			vchiq_log_error(vchiq_arm_log_level,
1049 				"vchiq has no connection to VideoCore");
1050 			return -ENOTCONN;
1051 		}
1052 
1053 		instance = kzalloc(sizeof(*instance), GFP_KERNEL);
1054 		if (!instance)
1055 			return -ENOMEM;
1056 
1057 		err = fd_allocfile(&fp, &fd);
1058 		if (err) {
1059 			kfree(instance);
1060 			return -err;
1061 		}
1062 
1063 		instance->state = state;
1064 		instance->l = l;
1065 
1066 #ifdef notyet
1067 		ret = vchiq_proc_add_instance(instance);
1068 		if (ret != 0) {
1069 			kfree(instance);
1070 			return ret;
1071 		}
1072 #endif
1073 
1074 		_sema_init(&instance->insert_event, 0);
1075 		_sema_init(&instance->remove_event, 0);
1076 		lmutex_init(&instance->completion_mutex);
1077 		lmutex_init(&instance->bulk_waiter_list_mutex);
1078 		INIT_LIST_HEAD(&instance->bulk_waiter_list);
1079 
1080 	}
1081 	else {
1082 		vchiq_log_error(vchiq_arm_log_level,
1083 			"Unknown minor device");
1084 		return -ENXIO;
1085 	}
1086 
1087 	return fd_clone(fp, fd, flags, &vchiq_fileops, instance);
1088 }
1089 
1090 /****************************************************************************
1091 *
1092 *   vchiq_release
1093 *
1094 ***************************************************************************/
1095 
1096 static int
1097 vchiq_close(struct file *fp)
1098 {
1099 	int ret = 0;
1100 	if (1) {
1101 		VCHIQ_INSTANCE_T instance;
1102 		VCHIQ_STATE_T *state = vchiq_get_state();
1103 		VCHIQ_SERVICE_T *service;
1104 		int i;
1105 
1106 		instance = fp->f_data;
1107 
1108 		vchiq_log_info(vchiq_arm_log_level,
1109 			"vchiq_release: instance=%lx",
1110 			(unsigned long)instance);
1111 
1112 		if (!state) {
1113 			ret = -EPERM;
1114 			goto out;
1115 		}
1116 
1117 		/* Ensure videocore is awake to allow termination. */
1118 		vchiq_use_internal(instance->state, NULL,
1119 				USE_TYPE_VCHIQ);
1120 
1121 		lmutex_lock(&instance->completion_mutex);
1122 
1123 		/* Wake the completion thread and ask it to exit */
1124 		instance->closing = 1;
1125 		up(&instance->insert_event);
1126 
1127 		lmutex_unlock(&instance->completion_mutex);
1128 
1129 		/* Wake the slot handler if the completion queue is full. */
1130 		up(&instance->remove_event);
1131 
1132 		/* Mark all services for termination... */
1133 		i = 0;
1134 		while ((service = next_service_by_instance(state, instance,
1135 			&i)) !=	NULL) {
1136 			USER_SERVICE_T *user_service = service->base.userdata;
1137 
1138 			/* Wake the slot handler if the msg queue is full. */
1139 			up(&user_service->remove_event);
1140 
1141 			vchiq_terminate_service_internal(service);
1142 			unlock_service(service);
1143 		}
1144 
1145 		/* ...and wait for them to die */
1146 		i = 0;
1147 		while ((service = next_service_by_instance(state, instance, &i))
1148 			!= NULL) {
1149 			USER_SERVICE_T *user_service = service->base.userdata;
1150 
1151 			down(&service->remove_event);
1152 
1153 			BUG_ON(service->srvstate != VCHIQ_SRVSTATE_FREE);
1154 
1155 			spin_lock(&msg_queue_spinlock);
1156 
1157 			while (user_service->msg_remove !=
1158 				user_service->msg_insert) {
1159 				VCHIQ_HEADER_T *header = user_service->
1160 					msg_queue[user_service->msg_remove &
1161 						(MSG_QUEUE_SIZE - 1)];
1162 				user_service->msg_remove++;
1163 				spin_unlock(&msg_queue_spinlock);
1164 
1165 				if (header)
1166 					vchiq_release_message(
1167 						service->handle,
1168 						header);
1169 				spin_lock(&msg_queue_spinlock);
1170 			}
1171 
1172 			spin_unlock(&msg_queue_spinlock);
1173 
1174 			unlock_service(service);
1175 		}
1176 
1177 		/* Release any closed services */
1178 		while (instance->completion_remove !=
1179 			instance->completion_insert) {
1180 			VCHIQ_COMPLETION_DATA_T *completion;
1181 			VCHIQ_SERVICE_T *service1;
1182 			completion = &instance->completions[
1183 				instance->completion_remove &
1184 				(MAX_COMPLETIONS - 1)];
1185 			service1 = completion->service_userdata;
1186 			if (completion->reason == VCHIQ_SERVICE_CLOSED)
1187 				unlock_service(service1);
1188 			instance->completion_remove++;
1189 		}
1190 
1191 		/* Release the PEER service count. */
1192 		vchiq_release_internal(instance->state, NULL);
1193 
1194 		{
1195 			struct list_head *pos, *next;
1196 			list_for_each_safe(pos, next,
1197 				&instance->bulk_waiter_list) {
1198 				struct bulk_waiter_node *waiter;
1199 				waiter = list_entry(pos,
1200 					struct bulk_waiter_node,
1201 					list);
1202 				list_del(pos);
1203 				vchiq_log_info(vchiq_arm_log_level,
1204 					"bulk_waiter - cleaned up %x "
1205 					"for lwp %p",
1206 					(unsigned int)waiter, waiter->l);
1207 		                _sema_destroy(&waiter->bulk_waiter.event);
1208 				kfree(waiter);
1209 			}
1210 		}
1211 
1212 	}
1213 	else {
1214 		vchiq_log_error(vchiq_arm_log_level,
1215 			"Unknown minor device");
1216 		ret = -ENXIO;
1217 	}
1218 
1219 out:
1220 	return ret;
1221 }
1222 
1223 /****************************************************************************
1224 *
1225 *   vchiq_dump
1226 *
1227 ***************************************************************************/
1228 
1229 void
1230 vchiq_dump(void *dump_context, const char *str, int len)
1231 {
1232 	DUMP_CONTEXT_T *context = (DUMP_CONTEXT_T *)dump_context;
1233 
1234 	if (context->actual < context->space) {
1235 		int copy_bytes;
1236 		if (context->offset > 0) {
1237 			int skip_bytes = min(len, (int)context->offset);
1238 			str += skip_bytes;
1239 			len -= skip_bytes;
1240 			context->offset -= skip_bytes;
1241 			if (context->offset > 0)
1242 				return;
1243 		}
1244 		copy_bytes = min(len, (int)(context->space - context->actual));
1245 		if (copy_bytes == 0)
1246 			return;
1247 		if (copy_to_user(context->buf + context->actual, str,
1248 			copy_bytes))
1249 			context->actual = -EFAULT;
1250 		context->actual += copy_bytes;
1251 		len -= copy_bytes;
1252 
1253 		/* If tne terminating NUL is included in the length, then it
1254 		** marks the end of a line and should be replaced with a
1255 		** carriage return. */
1256 		if ((len == 0) && (str[copy_bytes - 1] == '\0')) {
1257 			char cr = '\n';
1258 			if (copy_to_user(context->buf + context->actual - 1,
1259 				&cr, 1))
1260 				context->actual = -EFAULT;
1261 		}
1262 	}
1263 }
1264 
1265 /****************************************************************************
1266 *
1267 *   vchiq_dump_platform_instance_state
1268 *
1269 ***************************************************************************/
1270 
1271 void
1272 vchiq_dump_platform_instances(void *dump_context)
1273 {
1274 	VCHIQ_STATE_T *state = vchiq_get_state();
1275 	char buf[80];
1276 	int len;
1277 	int i;
1278 
1279 	/* There is no list of instances, so instead scan all services,
1280 		marking those that have been dumped. */
1281 
1282 	for (i = 0; i < state->unused_service; i++) {
1283 		VCHIQ_SERVICE_T *service = state->services[i];
1284 		VCHIQ_INSTANCE_T instance;
1285 
1286 		if (service && (service->base.callback == service_callback)) {
1287 			instance = service->instance;
1288 			if (instance)
1289 				instance->mark = 0;
1290 		}
1291 	}
1292 
1293 	for (i = 0; i < state->unused_service; i++) {
1294 		VCHIQ_SERVICE_T *service = state->services[i];
1295 		VCHIQ_INSTANCE_T instance;
1296 
1297 		if (service && (service->base.callback == service_callback)) {
1298 			instance = service->instance;
1299 			if (instance && !instance->mark) {
1300 				len = snprintf(buf, sizeof(buf),
1301 					"Instance %x: lwp %p,%s completions "
1302 						"%d/%d",
1303 					(unsigned int)instance, instance->l,
1304 					instance->connected ? " connected, " :
1305 						"",
1306 					instance->completion_insert -
1307 						instance->completion_remove,
1308 					MAX_COMPLETIONS);
1309 
1310 				vchiq_dump(dump_context, buf, len + 1);
1311 
1312 				instance->mark = 1;
1313 			}
1314 		}
1315 	}
1316 }
1317 
1318 /****************************************************************************
1319 *
1320 *   vchiq_dump_platform_service_state
1321 *
1322 ***************************************************************************/
1323 
1324 void
1325 vchiq_dump_platform_service_state(void *dump_context, VCHIQ_SERVICE_T *service)
1326 {
1327 	USER_SERVICE_T *user_service = (USER_SERVICE_T *)service->base.userdata;
1328 	char buf[80];
1329 	int len;
1330 
1331 	len = snprintf(buf, sizeof(buf), "  instance %x",
1332 		(unsigned int)service->instance);
1333 
1334 	if ((service->base.callback == service_callback) &&
1335 		user_service->is_vchi) {
1336 		len += snprintf(buf + len, sizeof(buf) - len,
1337 			", %d/%d messages",
1338 			user_service->msg_insert - user_service->msg_remove,
1339 			MSG_QUEUE_SIZE);
1340 
1341 		if (user_service->dequeue_pending)
1342 			len += snprintf(buf + len, sizeof(buf) - len,
1343 				" (dequeue pending)");
1344 	}
1345 
1346 	vchiq_dump(dump_context, buf, len + 1);
1347 }
1348 
1349 #ifdef notyet
1350 /****************************************************************************
1351 *
1352 *   dump_user_mem
1353 *
1354 ***************************************************************************/
1355 
1356 static void
1357 dump_phys_mem(void *virt_addr, uint32_t num_bytes)
1358 {
1359 	int            rc;
1360 	uint8_t       *end_virt_addr = virt_addr + num_bytes;
1361 	int            num_pages;
1362 	int            offset;
1363 	int            end_offset;
1364 	int            page_idx;
1365 	int            prev_idx;
1366 	struct page   *page;
1367 	struct page  **pages;
1368 	uint8_t       *kmapped_virt_ptr;
1369 
1370 	/* Align virtAddr and endVirtAddr to 16 byte boundaries. */
1371 
1372 	virt_addr = (void *)((unsigned long)virt_addr & ~0x0fuL);
1373 	end_virt_addr = (void *)(((unsigned long)end_virt_addr + 15uL) &
1374 		~0x0fuL);
1375 
1376 	offset = (int)(long)virt_addr & (PAGE_SIZE - 1);
1377 	end_offset = (int)(long)end_virt_addr & (PAGE_SIZE - 1);
1378 
1379 	num_pages = (offset + num_bytes + PAGE_SIZE - 1) / PAGE_SIZE;
1380 
1381 	pages = kmalloc(sizeof(struct page *) * num_pages, GFP_KERNEL);
1382 	if (pages == NULL) {
1383 		vchiq_log_error(vchiq_arm_log_level,
1384 			"Unable to allocation memory for %d pages\n",
1385 			num_pages);
1386 		return;
1387 	}
1388 
1389 	down_read(&current->mm->mmap_sem);
1390 	rc = get_user_pages(current,      /* task */
1391 		current->mm,              /* mm */
1392 		(unsigned long)virt_addr, /* start */
1393 		num_pages,                /* len */
1394 		0,                        /* write */
1395 		0,                        /* force */
1396 		pages,                    /* pages (array of page pointers) */
1397 		NULL);                    /* vmas */
1398 	up_read(&current->mm->mmap_sem);
1399 
1400 	prev_idx = -1;
1401 	page = NULL;
1402 
1403 	while (offset < end_offset) {
1404 
1405 		int page_offset = offset % PAGE_SIZE;
1406 		page_idx = offset / PAGE_SIZE;
1407 
1408 		if (page_idx != prev_idx) {
1409 
1410 			if (page != NULL)
1411 				kunmap(page);
1412 			page = pages[page_idx];
1413 			kmapped_virt_ptr = kmap(page);
1414 
1415 			prev_idx = page_idx;
1416 		}
1417 
1418 		if (vchiq_arm_log_level >= VCHIQ_LOG_TRACE)
1419 			vchiq_log_dump_mem("ph",
1420 				(uint32_t)(unsigned long)&kmapped_virt_ptr[
1421 					page_offset],
1422 				&kmapped_virt_ptr[page_offset], 16);
1423 
1424 		offset += 16;
1425 	}
1426 	if (page != NULL)
1427 		kunmap(page);
1428 
1429 	for (page_idx = 0; page_idx < num_pages; page_idx++)
1430 		page_cache_release(pages[page_idx]);
1431 
1432 	kfree(pages);
1433 }
1434 
1435 /****************************************************************************
1436 *
1437 *   vchiq_read
1438 *
1439 ***************************************************************************/
1440 
1441 static ssize_t
1442 vchiq_read(struct file *file, char __user *buf,
1443 	size_t count, loff_t *ppos)
1444 {
1445 	DUMP_CONTEXT_T context;
1446 	context.buf = buf;
1447 	context.actual = 0;
1448 	context.space = count;
1449 	context.offset = *ppos;
1450 
1451 	vchiq_dump_state(&context, &g_state);
1452 
1453 	*ppos += context.actual;
1454 
1455 	return context.actual;
1456 }
1457 #endif
1458 
1459 VCHIQ_STATE_T *
1460 vchiq_get_state(void)
1461 {
1462 
1463 	if (g_state.remote == NULL)
1464 		printk(KERN_ERR "%s: g_state.remote == NULL\n", __func__);
1465 	else if (g_state.remote->initialised != 1)
1466 		printk(KERN_NOTICE "%s: g_state.remote->initialised != 1 (%d)\n",
1467 			__func__, g_state.remote->initialised);
1468 
1469 	return ((g_state.remote != NULL) &&
1470 		(g_state.remote->initialised == 1)) ? &g_state : NULL;
1471 }
1472 
1473 /*
1474  * Autosuspend related functionality
1475  */
1476 
1477 int
1478 vchiq_videocore_wanted(VCHIQ_STATE_T *state)
1479 {
1480 	VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
1481 	if (!arm_state)
1482 		/* autosuspend not supported - always return wanted */
1483 		return 1;
1484 	else if (arm_state->blocked_count)
1485 		return 1;
1486 	else if (!arm_state->videocore_use_count)
1487 		/* usage count zero - check for override unless we're forcing */
1488 		if (arm_state->resume_blocked)
1489 			return 0;
1490 		else
1491 			return vchiq_platform_videocore_wanted(state);
1492 	else
1493 		/* non-zero usage count - videocore still required */
1494 		return 1;
1495 }
1496 
1497 static VCHIQ_STATUS_T
1498 vchiq_keepalive_vchiq_callback(VCHIQ_REASON_T reason,
1499 	VCHIQ_HEADER_T *header,
1500 	VCHIQ_SERVICE_HANDLE_T service_user,
1501 	void *bulk_user)
1502 {
1503 	vchiq_log_error(vchiq_susp_log_level,
1504 		"%s callback reason %d", __func__, reason);
1505 	return 0;
1506 }
1507 
1508 static int
1509 vchiq_keepalive_thread_func(void *v)
1510 {
1511 	VCHIQ_STATE_T *state = (VCHIQ_STATE_T *) v;
1512 	VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
1513 
1514 	VCHIQ_STATUS_T status;
1515 	VCHIQ_INSTANCE_T instance;
1516 	VCHIQ_SERVICE_HANDLE_T ka_handle;
1517 
1518 	VCHIQ_SERVICE_PARAMS_T params = {
1519 		.fourcc      = VCHIQ_MAKE_FOURCC('K', 'E', 'E', 'P'),
1520 		.callback    = vchiq_keepalive_vchiq_callback,
1521 		.version     = KEEPALIVE_VER,
1522 		.version_min = KEEPALIVE_VER_MIN
1523 	};
1524 
1525 	status = vchiq_initialise(&instance);
1526 	if (status != VCHIQ_SUCCESS) {
1527 		vchiq_log_error(vchiq_susp_log_level,
1528 			"%s vchiq_initialise failed %d", __func__, status);
1529 		goto exit;
1530 	}
1531 
1532 	status = vchiq_connect(instance);
1533 	if (status != VCHIQ_SUCCESS) {
1534 		vchiq_log_error(vchiq_susp_log_level,
1535 			"%s vchiq_connect failed %d", __func__, status);
1536 		goto shutdown;
1537 	}
1538 
1539 	status = vchiq_add_service(instance, &params, &ka_handle);
1540 	if (status != VCHIQ_SUCCESS) {
1541 		vchiq_log_error(vchiq_susp_log_level,
1542 			"%s vchiq_open_service failed %d", __func__, status);
1543 		goto shutdown;
1544 	}
1545 
1546 	while (1) {
1547 		long rc = 0, uc = 0;
1548 		if (wait_for_completion_interruptible(&arm_state->ka_evt)
1549 				!= 0) {
1550 			vchiq_log_error(vchiq_susp_log_level,
1551 				"%s interrupted", __func__);
1552 			flush_signals(current);
1553 			continue;
1554 		}
1555 
1556 		/* read and clear counters.  Do release_count then use_count to
1557 		 * prevent getting more releases than uses */
1558 		rc = atomic_xchg(&arm_state->ka_release_count, 0);
1559 		uc = atomic_xchg(&arm_state->ka_use_count, 0);
1560 
1561 		/* Call use/release service the requisite number of times.
1562 		 * Process use before release so use counts don't go negative */
1563 		while (uc--) {
1564 			atomic_inc(&arm_state->ka_use_ack_count);
1565 			status = vchiq_use_service(ka_handle);
1566 			if (status != VCHIQ_SUCCESS) {
1567 				vchiq_log_error(vchiq_susp_log_level,
1568 					"%s vchiq_use_service error %d",
1569 					__func__, status);
1570 			}
1571 		}
1572 		while (rc--) {
1573 			status = vchiq_release_service(ka_handle);
1574 			if (status != VCHIQ_SUCCESS) {
1575 				vchiq_log_error(vchiq_susp_log_level,
1576 					"%s vchiq_release_service error %d",
1577 					__func__, status);
1578 			}
1579 		}
1580 	}
1581 
1582 shutdown:
1583 	vchiq_shutdown(instance);
1584 exit:
1585 	return 0;
1586 }
1587 
1588 VCHIQ_STATUS_T
1589 vchiq_arm_init_state(VCHIQ_STATE_T *state, VCHIQ_ARM_STATE_T *arm_state)
1590 {
1591 	VCHIQ_STATUS_T status = VCHIQ_SUCCESS;
1592 
1593 	if (arm_state) {
1594 		rwlock_init(&arm_state->susp_res_lock);
1595 
1596 		init_completion(&arm_state->ka_evt);
1597 		atomic_set(&arm_state->ka_use_count, 0);
1598 		atomic_set(&arm_state->ka_use_ack_count, 0);
1599 		atomic_set(&arm_state->ka_release_count, 0);
1600 
1601 		init_completion(&arm_state->vc_suspend_complete);
1602 
1603 		init_completion(&arm_state->vc_resume_complete);
1604 		/* Initialise to 'done' state.  We only want to block on resume
1605 		 * completion while videocore is suspended. */
1606 		set_resume_state(arm_state, VC_RESUME_RESUMED);
1607 
1608 		init_completion(&arm_state->resume_blocker);
1609 		/* Initialise to 'done' state.  We only want to block on this
1610 		 * completion while resume is blocked */
1611 		complete_all(&arm_state->resume_blocker);
1612 
1613 		init_completion(&arm_state->blocked_blocker);
1614 		/* Initialise to 'done' state.  We only want to block on this
1615 		 * completion while things are waiting on the resume blocker */
1616 		complete_all(&arm_state->blocked_blocker);
1617 
1618 		arm_state->suspend_timer_timeout = SUSPEND_TIMER_TIMEOUT_MS;
1619 		arm_state->suspend_timer_running = 0;
1620 		init_timer(&arm_state->suspend_timer);
1621 		arm_state->suspend_timer.data = (unsigned long)(state);
1622 		arm_state->suspend_timer.function = suspend_timer_callback;
1623 
1624 		arm_state->first_connect = 0;
1625 
1626 	}
1627 	return status;
1628 }
1629 
1630 /*
1631 ** Functions to modify the state variables;
1632 **	set_suspend_state
1633 **	set_resume_state
1634 **
1635 ** There are more state variables than we might like, so ensure they remain in
1636 ** step.  Suspend and resume state are maintained separately, since most of
1637 ** these state machines can operate independently.  However, there are a few
1638 ** states where state transitions in one state machine cause a reset to the
1639 ** other state machine.  In addition, there are some completion events which
1640 ** need to occur on state machine reset and end-state(s), so these are also
1641 ** dealt with in these functions.
1642 **
1643 ** In all states we set the state variable according to the input, but in some
1644 ** cases we perform additional steps outlined below;
1645 **
1646 ** VC_SUSPEND_IDLE - Initialise the suspend completion at the same time.
1647 **			The suspend completion is completed after any suspend
1648 **			attempt.  When we reset the state machine we also reset
1649 **			the completion.  This reset occurs when videocore is
1650 **			resumed, and also if we initiate suspend after a suspend
1651 **			failure.
1652 **
1653 ** VC_SUSPEND_IN_PROGRESS - This state is considered the point of no return for
1654 **			suspend - ie from this point on we must try to suspend
1655 **			before resuming can occur.  We therefore also reset the
1656 **			resume state machine to VC_RESUME_IDLE in this state.
1657 **
1658 ** VC_SUSPEND_SUSPENDED - Suspend has completed successfully. Also call
1659 **			complete_all on the suspend completion to notify
1660 **			anything waiting for suspend to happen.
1661 **
1662 ** VC_SUSPEND_REJECTED - Videocore rejected suspend. Videocore will also
1663 **			initiate resume, so no need to alter resume state.
1664 **			We call complete_all on the suspend completion to notify
1665 **			of suspend rejection.
1666 **
1667 ** VC_SUSPEND_FAILED - We failed to initiate videocore suspend.  We notify the
1668 **			suspend completion and reset the resume state machine.
1669 **
1670 ** VC_RESUME_IDLE - Initialise the resume completion at the same time.  The
1671 **			resume completion is in it's 'done' state whenever
1672 **			videcore is running.  Therfore, the VC_RESUME_IDLE state
1673 **			implies that videocore is suspended.
1674 **			Hence, any thread which needs to wait until videocore is
1675 **			running can wait on this completion - it will only block
1676 **			if videocore is suspended.
1677 **
1678 ** VC_RESUME_RESUMED - Resume has completed successfully.  Videocore is running.
1679 **			Call complete_all on the resume completion to unblock
1680 **			any threads waiting for resume.	 Also reset the suspend
1681 **			state machine to it's idle state.
1682 **
1683 ** VC_RESUME_FAILED - Currently unused - no mechanism to fail resume exists.
1684 */
1685 
1686 inline void
1687 set_suspend_state(VCHIQ_ARM_STATE_T *arm_state,
1688 	enum vc_suspend_status new_state)
1689 {
1690 	/* set the state in all cases */
1691 	arm_state->vc_suspend_state = new_state;
1692 
1693 	/* state specific additional actions */
1694 	switch (new_state) {
1695 	case VC_SUSPEND_FORCE_CANCELED:
1696 		complete_all(&arm_state->vc_suspend_complete);
1697 		break;
1698 	case VC_SUSPEND_REJECTED:
1699 		complete_all(&arm_state->vc_suspend_complete);
1700 		break;
1701 	case VC_SUSPEND_FAILED:
1702 		complete_all(&arm_state->vc_suspend_complete);
1703 		arm_state->vc_resume_state = VC_RESUME_RESUMED;
1704 		complete_all(&arm_state->vc_resume_complete);
1705 		break;
1706 	case VC_SUSPEND_IDLE:
1707 		INIT_COMPLETION(arm_state->vc_suspend_complete);
1708 		break;
1709 	case VC_SUSPEND_REQUESTED:
1710 		break;
1711 	case VC_SUSPEND_IN_PROGRESS:
1712 		set_resume_state(arm_state, VC_RESUME_IDLE);
1713 		break;
1714 	case VC_SUSPEND_SUSPENDED:
1715 		complete_all(&arm_state->vc_suspend_complete);
1716 		break;
1717 	default:
1718 		BUG();
1719 		break;
1720 	}
1721 }
1722 
1723 inline void
1724 set_resume_state(VCHIQ_ARM_STATE_T *arm_state,
1725 	enum vc_resume_status new_state)
1726 {
1727 	/* set the state in all cases */
1728 	arm_state->vc_resume_state = new_state;
1729 
1730 	/* state specific additional actions */
1731 	switch (new_state) {
1732 	case VC_RESUME_FAILED:
1733 		break;
1734 	case VC_RESUME_IDLE:
1735 		INIT_COMPLETION(arm_state->vc_resume_complete);
1736 		break;
1737 	case VC_RESUME_REQUESTED:
1738 		break;
1739 	case VC_RESUME_IN_PROGRESS:
1740 		break;
1741 	case VC_RESUME_RESUMED:
1742 		complete_all(&arm_state->vc_resume_complete);
1743 		set_suspend_state(arm_state, VC_SUSPEND_IDLE);
1744 		break;
1745 	default:
1746 		BUG();
1747 		break;
1748 	}
1749 }
1750 
1751 
1752 /* should be called with the write lock held */
1753 inline void
1754 start_suspend_timer(VCHIQ_ARM_STATE_T *arm_state)
1755 {
1756 	del_timer(&arm_state->suspend_timer);
1757 	arm_state->suspend_timer.expires = jiffies +
1758 		msecs_to_jiffies(arm_state->
1759 			suspend_timer_timeout);
1760 	add_timer(&arm_state->suspend_timer);
1761 	arm_state->suspend_timer_running = 1;
1762 }
1763 
1764 /* should be called with the write lock held */
1765 static inline void
1766 stop_suspend_timer(VCHIQ_ARM_STATE_T *arm_state)
1767 {
1768 	if (arm_state->suspend_timer_running) {
1769 		del_timer(&arm_state->suspend_timer);
1770 		arm_state->suspend_timer_running = 0;
1771 	}
1772 }
1773 
1774 static inline int
1775 need_resume(VCHIQ_STATE_T *state)
1776 {
1777 	VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
1778 	return (arm_state->vc_suspend_state > VC_SUSPEND_IDLE) &&
1779 			(arm_state->vc_resume_state < VC_RESUME_REQUESTED) &&
1780 			vchiq_videocore_wanted(state);
1781 }
1782 
1783 static int
1784 block_resume(VCHIQ_ARM_STATE_T *arm_state)
1785 {
1786 	int status = VCHIQ_SUCCESS;
1787 	const unsigned long timeout_val =
1788 				msecs_to_jiffies(FORCE_SUSPEND_TIMEOUT_MS);
1789 	int resume_count = 0;
1790 
1791 	/* Allow any threads which were blocked by the last force suspend to
1792 	 * complete if they haven't already.  Only give this one shot; if
1793 	 * blocked_count is incremented after blocked_blocker is completed
1794 	 * (which only happens when blocked_count hits 0) then those threads
1795 	 * will have to wait until next time around */
1796 	if (arm_state->blocked_count) {
1797 		INIT_COMPLETION(arm_state->blocked_blocker);
1798 		write_unlock_bh(&arm_state->susp_res_lock);
1799 		vchiq_log_info(vchiq_susp_log_level, "%s wait for previously "
1800 			"blocked clients", __func__);
1801 		if (wait_for_completion_interruptible_timeout(
1802 				&arm_state->blocked_blocker, timeout_val)
1803 					<= 0) {
1804 			vchiq_log_error(vchiq_susp_log_level, "%s wait for "
1805 				"previously blocked clients failed" , __func__);
1806 			status = VCHIQ_ERROR;
1807 			write_lock_bh(&arm_state->susp_res_lock);
1808 			goto out;
1809 		}
1810 		vchiq_log_info(vchiq_susp_log_level, "%s previously blocked "
1811 			"clients resumed", __func__);
1812 		write_lock_bh(&arm_state->susp_res_lock);
1813 	}
1814 
1815 	/* We need to wait for resume to complete if it's in process */
1816 	while (arm_state->vc_resume_state != VC_RESUME_RESUMED &&
1817 			arm_state->vc_resume_state > VC_RESUME_IDLE) {
1818 		if (resume_count > 1) {
1819 			status = VCHIQ_ERROR;
1820 			vchiq_log_error(vchiq_susp_log_level, "%s waited too "
1821 				"many times for resume" , __func__);
1822 			goto out;
1823 		}
1824 		write_unlock_bh(&arm_state->susp_res_lock);
1825 		vchiq_log_info(vchiq_susp_log_level, "%s wait for resume",
1826 			__func__);
1827 		if (wait_for_completion_interruptible_timeout(
1828 				&arm_state->vc_resume_complete, timeout_val)
1829 					<= 0) {
1830 			vchiq_log_error(vchiq_susp_log_level, "%s wait for "
1831 				"resume failed (%s)", __func__,
1832 				resume_state_names[arm_state->vc_resume_state +
1833 							VC_RESUME_NUM_OFFSET]);
1834 			status = VCHIQ_ERROR;
1835 			write_lock_bh(&arm_state->susp_res_lock);
1836 			goto out;
1837 		}
1838 		vchiq_log_info(vchiq_susp_log_level, "%s resumed", __func__);
1839 		write_lock_bh(&arm_state->susp_res_lock);
1840 		resume_count++;
1841 	}
1842 	INIT_COMPLETION(arm_state->resume_blocker);
1843 	arm_state->resume_blocked = 1;
1844 
1845 out:
1846 	return status;
1847 }
1848 
1849 static inline void
1850 unblock_resume(VCHIQ_ARM_STATE_T *arm_state)
1851 {
1852 	complete_all(&arm_state->resume_blocker);
1853 	arm_state->resume_blocked = 0;
1854 }
1855 
1856 /* Initiate suspend via slot handler. Should be called with the write lock
1857  * held */
1858 VCHIQ_STATUS_T
1859 vchiq_arm_vcsuspend(VCHIQ_STATE_T *state)
1860 {
1861 	VCHIQ_STATUS_T status = VCHIQ_ERROR;
1862 	VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
1863 
1864 	if (!arm_state)
1865 		goto out;
1866 
1867 	vchiq_log_trace(vchiq_susp_log_level, "%s", __func__);
1868 	status = VCHIQ_SUCCESS;
1869 
1870 
1871 	switch (arm_state->vc_suspend_state) {
1872 	case VC_SUSPEND_REQUESTED:
1873 		vchiq_log_info(vchiq_susp_log_level, "%s: suspend already "
1874 			"requested", __func__);
1875 		break;
1876 	case VC_SUSPEND_IN_PROGRESS:
1877 		vchiq_log_info(vchiq_susp_log_level, "%s: suspend already in "
1878 			"progress", __func__);
1879 		break;
1880 
1881 	default:
1882 		/* We don't expect to be in other states, so log but continue
1883 		 * anyway */
1884 		vchiq_log_error(vchiq_susp_log_level,
1885 			"%s unexpected suspend state %s", __func__,
1886 			suspend_state_names[arm_state->vc_suspend_state +
1887 						VC_SUSPEND_NUM_OFFSET]);
1888 		/* fall through */
1889 	case VC_SUSPEND_REJECTED:
1890 	case VC_SUSPEND_FAILED:
1891 		/* Ensure any idle state actions have been run */
1892 		set_suspend_state(arm_state, VC_SUSPEND_IDLE);
1893 		/* fall through */
1894 	case VC_SUSPEND_IDLE:
1895 		vchiq_log_info(vchiq_susp_log_level,
1896 			"%s: suspending", __func__);
1897 		set_suspend_state(arm_state, VC_SUSPEND_REQUESTED);
1898 		/* kick the slot handler thread to initiate suspend */
1899 		request_poll(state, NULL, 0);
1900 		break;
1901 	}
1902 
1903 out:
1904 	vchiq_log_trace(vchiq_susp_log_level, "%s exit %d", __func__, status);
1905 	return status;
1906 }
1907 
1908 void
1909 vchiq_platform_check_suspend(VCHIQ_STATE_T *state)
1910 {
1911 	VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
1912 	int susp = 0;
1913 
1914 	if (!arm_state)
1915 		goto out;
1916 
1917 	vchiq_log_trace(vchiq_susp_log_level, "%s", __func__);
1918 
1919 	write_lock_bh(&arm_state->susp_res_lock);
1920 	if (arm_state->vc_suspend_state == VC_SUSPEND_REQUESTED &&
1921 			arm_state->vc_resume_state == VC_RESUME_RESUMED) {
1922 		set_suspend_state(arm_state, VC_SUSPEND_IN_PROGRESS);
1923 		susp = 1;
1924 	}
1925 	write_unlock_bh(&arm_state->susp_res_lock);
1926 
1927 	if (susp)
1928 		vchiq_platform_suspend(state);
1929 
1930 out:
1931 	vchiq_log_trace(vchiq_susp_log_level, "%s exit", __func__);
1932 	return;
1933 }
1934 
1935 
1936 static void
1937 output_timeout_error(VCHIQ_STATE_T *state)
1938 {
1939 	VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
1940 	char service_err[50] = "";
1941 	int vc_use_count = arm_state->videocore_use_count;
1942 	int active_services = state->unused_service;
1943 	int i;
1944 
1945 	if (!arm_state->videocore_use_count) {
1946 		snprintf(service_err, 50, " Videocore usecount is 0");
1947 		goto output_msg;
1948 	}
1949 	for (i = 0; i < active_services; i++) {
1950 		VCHIQ_SERVICE_T *service_ptr = state->services[i];
1951 		if (service_ptr && service_ptr->service_use_count &&
1952 			(service_ptr->srvstate != VCHIQ_SRVSTATE_FREE)) {
1953 			snprintf(service_err, 50, " %c%c%c%c(%8x) service has "
1954 				"use count %d%s", VCHIQ_FOURCC_AS_4CHARS(
1955 					service_ptr->base.fourcc),
1956 				 service_ptr->client_id,
1957 				 service_ptr->service_use_count,
1958 				 service_ptr->service_use_count ==
1959 					 vc_use_count ? "" : " (+ more)");
1960 			break;
1961 		}
1962 	}
1963 
1964 output_msg:
1965 	vchiq_log_error(vchiq_susp_log_level,
1966 		"timed out waiting for vc suspend (%d).%s",
1967 		 arm_state->autosuspend_override, service_err);
1968 
1969 }
1970 
1971 /* Try to get videocore into suspended state, regardless of autosuspend state.
1972 ** We don't actually force suspend, since videocore may get into a bad state
1973 ** if we force suspend at a bad time.  Instead, we wait for autosuspend to
1974 ** determine a good point to suspend.  If this doesn't happen within 100ms we
1975 ** report failure.
1976 **
1977 ** Returns VCHIQ_SUCCESS if videocore suspended successfully, VCHIQ_RETRY if
1978 ** videocore failed to suspend in time or VCHIQ_ERROR if interrupted.
1979 */
1980 VCHIQ_STATUS_T
1981 vchiq_arm_force_suspend(VCHIQ_STATE_T *state)
1982 {
1983 	VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
1984 	VCHIQ_STATUS_T status = VCHIQ_ERROR;
1985 	long rc = 0;
1986 	int repeat = -1;
1987 
1988 	if (!arm_state)
1989 		goto out;
1990 
1991 	vchiq_log_trace(vchiq_susp_log_level, "%s", __func__);
1992 
1993 	write_lock_bh(&arm_state->susp_res_lock);
1994 
1995 	status = block_resume(arm_state);
1996 	if (status != VCHIQ_SUCCESS)
1997 		goto unlock;
1998 	if (arm_state->vc_suspend_state == VC_SUSPEND_SUSPENDED) {
1999 		/* Already suspended - just block resume and exit */
2000 		vchiq_log_info(vchiq_susp_log_level, "%s already suspended",
2001 			__func__);
2002 		status = VCHIQ_SUCCESS;
2003 		goto unlock;
2004 	} else if (arm_state->vc_suspend_state <= VC_SUSPEND_IDLE) {
2005 		/* initiate suspend immediately in the case that we're waiting
2006 		 * for the timeout */
2007 		stop_suspend_timer(arm_state);
2008 		if (!vchiq_videocore_wanted(state)) {
2009 			vchiq_log_info(vchiq_susp_log_level, "%s videocore "
2010 				"idle, initiating suspend", __func__);
2011 			status = vchiq_arm_vcsuspend(state);
2012 		} else if (arm_state->autosuspend_override <
2013 						FORCE_SUSPEND_FAIL_MAX) {
2014 			vchiq_log_info(vchiq_susp_log_level, "%s letting "
2015 				"videocore go idle", __func__);
2016 			status = VCHIQ_SUCCESS;
2017 		} else {
2018 			vchiq_log_warning(vchiq_susp_log_level, "%s failed too "
2019 				"many times - attempting suspend", __func__);
2020 			status = vchiq_arm_vcsuspend(state);
2021 		}
2022 	} else {
2023 		vchiq_log_info(vchiq_susp_log_level, "%s videocore suspend "
2024 			"in progress - wait for completion", __func__);
2025 		status = VCHIQ_SUCCESS;
2026 	}
2027 
2028 	/* Wait for suspend to happen due to system idle (not forced..) */
2029 	if (status != VCHIQ_SUCCESS)
2030 		goto unblock_resume;
2031 
2032 	do {
2033 		write_unlock_bh(&arm_state->susp_res_lock);
2034 
2035 		rc = wait_for_completion_interruptible_timeout(
2036 				&arm_state->vc_suspend_complete,
2037 				msecs_to_jiffies(FORCE_SUSPEND_TIMEOUT_MS));
2038 
2039 		write_lock_bh(&arm_state->susp_res_lock);
2040 		if (rc < 0) {
2041 			vchiq_log_warning(vchiq_susp_log_level, "%s "
2042 				"interrupted waiting for suspend", __func__);
2043 			status = VCHIQ_ERROR;
2044 			goto unblock_resume;
2045 		} else if (rc == 0) {
2046 			if (arm_state->vc_suspend_state > VC_SUSPEND_IDLE) {
2047 				/* Repeat timeout once if in progress */
2048 				if (repeat < 0) {
2049 					repeat = 1;
2050 					continue;
2051 				}
2052 			}
2053 			arm_state->autosuspend_override++;
2054 			output_timeout_error(state);
2055 
2056 			status = VCHIQ_RETRY;
2057 			goto unblock_resume;
2058 		}
2059 	} while (0 < (repeat--));
2060 
2061 	/* Check and report state in case we need to abort ARM suspend */
2062 	if (arm_state->vc_suspend_state != VC_SUSPEND_SUSPENDED) {
2063 		status = VCHIQ_RETRY;
2064 		vchiq_log_error(vchiq_susp_log_level,
2065 			"%s videocore suspend failed (state %s)", __func__,
2066 			suspend_state_names[arm_state->vc_suspend_state +
2067 						VC_SUSPEND_NUM_OFFSET]);
2068 		/* Reset the state only if it's still in an error state.
2069 		 * Something could have already initiated another suspend. */
2070 		if (arm_state->vc_suspend_state < VC_SUSPEND_IDLE)
2071 			set_suspend_state(arm_state, VC_SUSPEND_IDLE);
2072 
2073 		goto unblock_resume;
2074 	}
2075 
2076 	/* successfully suspended - unlock and exit */
2077 	goto unlock;
2078 
2079 unblock_resume:
2080 	/* all error states need to unblock resume before exit */
2081 	unblock_resume(arm_state);
2082 
2083 unlock:
2084 	write_unlock_bh(&arm_state->susp_res_lock);
2085 
2086 out:
2087 	vchiq_log_trace(vchiq_susp_log_level, "%s exit %d", __func__, status);
2088 	return status;
2089 }
2090 
2091 void
2092 vchiq_check_suspend(VCHIQ_STATE_T *state)
2093 {
2094 	VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
2095 
2096 	if (!arm_state)
2097 		goto out;
2098 
2099 	vchiq_log_trace(vchiq_susp_log_level, "%s", __func__);
2100 
2101 	write_lock_bh(&arm_state->susp_res_lock);
2102 	if (arm_state->vc_suspend_state != VC_SUSPEND_SUSPENDED &&
2103 			arm_state->first_connect &&
2104 			!vchiq_videocore_wanted(state)) {
2105 		vchiq_arm_vcsuspend(state);
2106 	}
2107 	write_unlock_bh(&arm_state->susp_res_lock);
2108 
2109 out:
2110 	vchiq_log_trace(vchiq_susp_log_level, "%s exit", __func__);
2111 	return;
2112 }
2113 
2114 
2115 int
2116 vchiq_arm_allow_resume(VCHIQ_STATE_T *state)
2117 {
2118 	VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
2119 	int resume = 0;
2120 	int ret = -1;
2121 
2122 	if (!arm_state)
2123 		goto out;
2124 
2125 	vchiq_log_trace(vchiq_susp_log_level, "%s", __func__);
2126 
2127 	write_lock_bh(&arm_state->susp_res_lock);
2128 	unblock_resume(arm_state);
2129 	resume = vchiq_check_resume(state);
2130 	write_unlock_bh(&arm_state->susp_res_lock);
2131 
2132 	if (resume) {
2133 		if (wait_for_completion_interruptible(
2134 			&arm_state->vc_resume_complete) < 0) {
2135 			vchiq_log_error(vchiq_susp_log_level,
2136 				"%s interrupted", __func__);
2137 			/* failed, cannot accurately derive suspend
2138 			 * state, so exit early. */
2139 			goto out;
2140 		}
2141 	}
2142 
2143 	read_lock_bh(&arm_state->susp_res_lock);
2144 	if (arm_state->vc_suspend_state == VC_SUSPEND_SUSPENDED) {
2145 		vchiq_log_info(vchiq_susp_log_level,
2146 				"%s: Videocore remains suspended", __func__);
2147 	} else {
2148 		vchiq_log_info(vchiq_susp_log_level,
2149 				"%s: Videocore resumed", __func__);
2150 		ret = 0;
2151 	}
2152 	read_unlock_bh(&arm_state->susp_res_lock);
2153 out:
2154 	vchiq_log_trace(vchiq_susp_log_level, "%s exit %d", __func__, ret);
2155 	return ret;
2156 }
2157 
2158 /* This function should be called with the write lock held */
2159 int
2160 vchiq_check_resume(VCHIQ_STATE_T *state)
2161 {
2162 	VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
2163 	int resume = 0;
2164 
2165 	if (!arm_state)
2166 		goto out;
2167 
2168 	vchiq_log_trace(vchiq_susp_log_level, "%s", __func__);
2169 
2170 	if (need_resume(state)) {
2171 		set_resume_state(arm_state, VC_RESUME_REQUESTED);
2172 		request_poll(state, NULL, 0);
2173 		resume = 1;
2174 	}
2175 
2176 out:
2177 	vchiq_log_trace(vchiq_susp_log_level, "%s exit", __func__);
2178 	return resume;
2179 }
2180 
2181 #ifdef notyet
2182 void
2183 vchiq_platform_check_resume(VCHIQ_STATE_T *state)
2184 {
2185 	VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
2186 	int res = 0;
2187 
2188 	if (!arm_state)
2189 		goto out;
2190 
2191 	vchiq_log_trace(vchiq_susp_log_level, "%s", __func__);
2192 
2193 	write_lock_bh(&arm_state->susp_res_lock);
2194 	if (arm_state->wake_address == 0) {
2195 		vchiq_log_info(vchiq_susp_log_level,
2196 					"%s: already awake", __func__);
2197 		goto unlock;
2198 	}
2199 	if (arm_state->vc_resume_state == VC_RESUME_IN_PROGRESS) {
2200 		vchiq_log_info(vchiq_susp_log_level,
2201 					"%s: already resuming", __func__);
2202 		goto unlock;
2203 	}
2204 
2205 	if (arm_state->vc_resume_state == VC_RESUME_REQUESTED) {
2206 		set_resume_state(arm_state, VC_RESUME_IN_PROGRESS);
2207 		res = 1;
2208 	} else
2209 		vchiq_log_trace(vchiq_susp_log_level,
2210 				"%s: not resuming (resume state %s)", __func__,
2211 				resume_state_names[arm_state->vc_resume_state +
2212 							VC_RESUME_NUM_OFFSET]);
2213 
2214 unlock:
2215 	write_unlock_bh(&arm_state->susp_res_lock);
2216 
2217 	if (res)
2218 		vchiq_platform_resume(state);
2219 
2220 out:
2221 	vchiq_log_trace(vchiq_susp_log_level, "%s exit", __func__);
2222 	return;
2223 
2224 }
2225 #endif
2226 
2227 
2228 
2229 VCHIQ_STATUS_T
2230 vchiq_use_internal(VCHIQ_STATE_T *state, VCHIQ_SERVICE_T *service,
2231 		enum USE_TYPE_E use_type)
2232 {
2233 	VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
2234 	VCHIQ_STATUS_T ret = VCHIQ_SUCCESS;
2235 	char entity[16];
2236 	int *entity_uc;
2237 	int local_uc, local_entity_uc;
2238 
2239 	if (!arm_state)
2240 		goto out;
2241 
2242 	vchiq_log_trace(vchiq_susp_log_level, "%s", __func__);
2243 
2244 	if (use_type == USE_TYPE_VCHIQ) {
2245 		snprintf(entity, sizeof(entity), "VCHIQ:   ");
2246 		entity_uc = &arm_state->peer_use_count;
2247 	} else if (service) {
2248 		snprintf(entity, sizeof(entity), "%c%c%c%c:%8x",
2249 			VCHIQ_FOURCC_AS_4CHARS(service->base.fourcc),
2250 			service->client_id);
2251 		entity_uc = &service->service_use_count;
2252 	} else {
2253 		vchiq_log_error(vchiq_susp_log_level, "%s null service "
2254 				"ptr", __func__);
2255 		ret = VCHIQ_ERROR;
2256 		goto out;
2257 	}
2258 
2259 	write_lock_bh(&arm_state->susp_res_lock);
2260 	while (arm_state->resume_blocked) {
2261 		/* If we call 'use' while force suspend is waiting for suspend,
2262 		 * then we're about to block the thread which the force is
2263 		 * waiting to complete, so we're bound to just time out. In this
2264 		 * case, set the suspend state such that the wait will be
2265 		 * canceled, so we can complete as quickly as possible. */
2266 		if (arm_state->resume_blocked && arm_state->vc_suspend_state ==
2267 				VC_SUSPEND_IDLE) {
2268 			set_suspend_state(arm_state, VC_SUSPEND_FORCE_CANCELED);
2269 			break;
2270 		}
2271 		/* If suspend is already in progress then we need to block */
2272 		if (!try_wait_for_completion(&arm_state->resume_blocker)) {
2273 			/* Indicate that there are threads waiting on the resume
2274 			 * blocker.  These need to be allowed to complete before
2275 			 * a _second_ call to force suspend can complete,
2276 			 * otherwise low priority threads might never actually
2277 			 * continue */
2278 			arm_state->blocked_count++;
2279 			write_unlock_bh(&arm_state->susp_res_lock);
2280 			vchiq_log_info(vchiq_susp_log_level, "%s %s resume "
2281 				"blocked - waiting...", __func__, entity);
2282 			if (wait_for_completion_killable(
2283 					&arm_state->resume_blocker) != 0) {
2284 				vchiq_log_error(vchiq_susp_log_level, "%s %s "
2285 					"wait for resume blocker interrupted",
2286 					__func__, entity);
2287 				ret = VCHIQ_ERROR;
2288 				write_lock_bh(&arm_state->susp_res_lock);
2289 				arm_state->blocked_count--;
2290 				write_unlock_bh(&arm_state->susp_res_lock);
2291 				goto out;
2292 			}
2293 			vchiq_log_info(vchiq_susp_log_level, "%s %s resume "
2294 				"unblocked", __func__, entity);
2295 			write_lock_bh(&arm_state->susp_res_lock);
2296 			if (--arm_state->blocked_count == 0)
2297 				complete_all(&arm_state->blocked_blocker);
2298 		}
2299 	}
2300 
2301 	stop_suspend_timer(arm_state);
2302 
2303 	local_uc = ++arm_state->videocore_use_count;
2304 	local_entity_uc = ++(*entity_uc);
2305 
2306 	/* If there's a pending request which hasn't yet been serviced then
2307 	 * just clear it.  If we're past VC_SUSPEND_REQUESTED state then
2308 	 * vc_resume_complete will block until we either resume or fail to
2309 	 * suspend */
2310 	if (arm_state->vc_suspend_state <= VC_SUSPEND_REQUESTED)
2311 		set_suspend_state(arm_state, VC_SUSPEND_IDLE);
2312 
2313 	if ((use_type != USE_TYPE_SERVICE_NO_RESUME) && need_resume(state)) {
2314 		set_resume_state(arm_state, VC_RESUME_REQUESTED);
2315 		vchiq_log_info(vchiq_susp_log_level,
2316 			"%s %s count %d, state count %d",
2317 			__func__, entity, local_entity_uc, local_uc);
2318 		request_poll(state, NULL, 0);
2319 	} else
2320 		vchiq_log_trace(vchiq_susp_log_level,
2321 			"%s %s count %d, state count %d",
2322 			__func__, entity, *entity_uc, local_uc);
2323 
2324 
2325 	write_unlock_bh(&arm_state->susp_res_lock);
2326 
2327 	/* Completion is in a done state when we're not suspended, so this won't
2328 	 * block for the non-suspended case. */
2329 	if (!try_wait_for_completion(&arm_state->vc_resume_complete)) {
2330 		vchiq_log_info(vchiq_susp_log_level, "%s %s wait for resume",
2331 			__func__, entity);
2332 		if (wait_for_completion_killable(
2333 				&arm_state->vc_resume_complete) != 0) {
2334 			vchiq_log_error(vchiq_susp_log_level, "%s %s wait for "
2335 				"resume interrupted", __func__, entity);
2336 			ret = VCHIQ_ERROR;
2337 			goto out;
2338 		}
2339 		vchiq_log_info(vchiq_susp_log_level, "%s %s resumed", __func__,
2340 			entity);
2341 	}
2342 
2343 	if (ret == VCHIQ_SUCCESS) {
2344 		VCHIQ_STATUS_T status = VCHIQ_SUCCESS;
2345 		long ack_cnt = atomic_xchg(&arm_state->ka_use_ack_count, 0);
2346 		while (ack_cnt && (status == VCHIQ_SUCCESS)) {
2347 			/* Send the use notify to videocore */
2348 			status = vchiq_send_remote_use_active(state);
2349 			if (status == VCHIQ_SUCCESS)
2350 				ack_cnt--;
2351 			else
2352 				atomic_add(ack_cnt,
2353 					&arm_state->ka_use_ack_count);
2354 		}
2355 	}
2356 
2357 out:
2358 	vchiq_log_trace(vchiq_susp_log_level, "%s exit %d", __func__, ret);
2359 	return ret;
2360 }
2361 
2362 VCHIQ_STATUS_T
2363 vchiq_release_internal(VCHIQ_STATE_T *state, VCHIQ_SERVICE_T *service)
2364 {
2365 	VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
2366 	VCHIQ_STATUS_T ret = VCHIQ_SUCCESS;
2367 	char entity[16];
2368 	int *entity_uc;
2369 
2370 	if (!arm_state)
2371 		goto out;
2372 
2373 	vchiq_log_trace(vchiq_susp_log_level, "%s", __func__);
2374 
2375 	if (service) {
2376 		snprintf(entity, sizeof(entity), "%c%c%c%c:%8x",
2377 			VCHIQ_FOURCC_AS_4CHARS(service->base.fourcc),
2378 			service->client_id);
2379 		entity_uc = &service->service_use_count;
2380 	} else {
2381 		snprintf(entity, sizeof(entity), "PEER:   ");
2382 		entity_uc = &arm_state->peer_use_count;
2383 	}
2384 
2385 	write_lock_bh(&arm_state->susp_res_lock);
2386 	if (!arm_state->videocore_use_count || !(*entity_uc)) {
2387 		/* Don't use BUG_ON - don't allow user thread to crash kernel */
2388 		WARN_ON(!arm_state->videocore_use_count);
2389 		WARN_ON(!(*entity_uc));
2390 		ret = VCHIQ_ERROR;
2391 		goto unlock;
2392 	}
2393 	--arm_state->videocore_use_count;
2394 	--(*entity_uc);
2395 
2396 	if (!vchiq_videocore_wanted(state)) {
2397 		if (vchiq_platform_use_suspend_timer() &&
2398 				!arm_state->resume_blocked) {
2399 			/* Only use the timer if we're not trying to force
2400 			 * suspend (=> resume_blocked) */
2401 			start_suspend_timer(arm_state);
2402 		} else {
2403 			vchiq_log_info(vchiq_susp_log_level,
2404 				"%s %s count %d, state count %d - suspending",
2405 				__func__, entity, *entity_uc,
2406 				arm_state->videocore_use_count);
2407 			vchiq_arm_vcsuspend(state);
2408 		}
2409 	} else
2410 		vchiq_log_trace(vchiq_susp_log_level,
2411 			"%s %s count %d, state count %d",
2412 			__func__, entity, *entity_uc,
2413 			arm_state->videocore_use_count);
2414 
2415 unlock:
2416 	write_unlock_bh(&arm_state->susp_res_lock);
2417 
2418 out:
2419 	vchiq_log_trace(vchiq_susp_log_level, "%s exit %d", __func__, ret);
2420 	return ret;
2421 }
2422 
2423 void
2424 vchiq_on_remote_use(VCHIQ_STATE_T *state)
2425 {
2426 	VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
2427 	vchiq_log_trace(vchiq_susp_log_level, "%s", __func__);
2428 	atomic_inc(&arm_state->ka_use_count);
2429 	complete(&arm_state->ka_evt);
2430 }
2431 
2432 void
2433 vchiq_on_remote_release(VCHIQ_STATE_T *state)
2434 {
2435 	VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
2436 	vchiq_log_trace(vchiq_susp_log_level, "%s", __func__);
2437 	atomic_inc(&arm_state->ka_release_count);
2438 	complete(&arm_state->ka_evt);
2439 }
2440 
2441 VCHIQ_STATUS_T
2442 vchiq_use_service_internal(VCHIQ_SERVICE_T *service)
2443 {
2444 	return vchiq_use_internal(service->state, service, USE_TYPE_SERVICE);
2445 }
2446 
2447 VCHIQ_STATUS_T
2448 vchiq_release_service_internal(VCHIQ_SERVICE_T *service)
2449 {
2450 	return vchiq_release_internal(service->state, service);
2451 }
2452 
2453 static void suspend_timer_callback(unsigned long context)
2454 {
2455 	VCHIQ_STATE_T *state = (VCHIQ_STATE_T *)context;
2456 	VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
2457 	if (!arm_state)
2458 		goto out;
2459 	vchiq_log_info(vchiq_susp_log_level,
2460 		"%s - suspend timer expired - check suspend", __func__);
2461 	vchiq_check_suspend(state);
2462 out:
2463 	return;
2464 }
2465 
2466 VCHIQ_STATUS_T
2467 vchiq_use_service_no_resume(VCHIQ_SERVICE_HANDLE_T handle)
2468 {
2469 	VCHIQ_STATUS_T ret = VCHIQ_ERROR;
2470 	VCHIQ_SERVICE_T *service = find_service_by_handle(handle);
2471 	if (service) {
2472 		ret = vchiq_use_internal(service->state, service,
2473 				USE_TYPE_SERVICE_NO_RESUME);
2474 		unlock_service(service);
2475 	}
2476 	return ret;
2477 }
2478 
2479 VCHIQ_STATUS_T
2480 vchiq_use_service(VCHIQ_SERVICE_HANDLE_T handle)
2481 {
2482 	VCHIQ_STATUS_T ret = VCHIQ_ERROR;
2483 	VCHIQ_SERVICE_T *service = find_service_by_handle(handle);
2484 	if (service) {
2485 		ret = vchiq_use_internal(service->state, service,
2486 				USE_TYPE_SERVICE);
2487 		unlock_service(service);
2488 	}
2489 	return ret;
2490 }
2491 
2492 VCHIQ_STATUS_T
2493 vchiq_release_service(VCHIQ_SERVICE_HANDLE_T handle)
2494 {
2495 	VCHIQ_STATUS_T ret = VCHIQ_ERROR;
2496 	VCHIQ_SERVICE_T *service = find_service_by_handle(handle);
2497 	if (service) {
2498 		ret = vchiq_release_internal(service->state, service);
2499 		unlock_service(service);
2500 	}
2501 	return ret;
2502 }
2503 
2504 void
2505 vchiq_dump_service_use_state(VCHIQ_STATE_T *state)
2506 {
2507 	VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
2508 	int i, j = 0;
2509 	/* Only dump 64 services */
2510 	static const int local_max_services = 64;
2511 	/* If there's more than 64 services, only dump ones with
2512 	 * non-zero counts */
2513 	int only_nonzero = 0;
2514 	static const char *nz = "<-- preventing suspend";
2515 
2516 	enum vc_suspend_status vc_suspend_state;
2517 	enum vc_resume_status  vc_resume_state;
2518 	int peer_count;
2519 	int vc_use_count;
2520 	int active_services;
2521 	struct service_data_struct {
2522 		int fourcc;
2523 		int clientid;
2524 		int use_count;
2525 	} service_data[local_max_services];
2526 
2527 	if (!arm_state)
2528 		return;
2529 
2530 	read_lock_bh(&arm_state->susp_res_lock);
2531 	vc_suspend_state = arm_state->vc_suspend_state;
2532 	vc_resume_state  = arm_state->vc_resume_state;
2533 	peer_count = arm_state->peer_use_count;
2534 	vc_use_count = arm_state->videocore_use_count;
2535 	active_services = state->unused_service;
2536 	if (active_services > local_max_services)
2537 		only_nonzero = 1;
2538 
2539 	for (i = 0; (i < active_services) && (j < local_max_services); i++) {
2540 		VCHIQ_SERVICE_T *service_ptr = state->services[i];
2541 		if (!service_ptr)
2542 			continue;
2543 
2544 		if (only_nonzero && !service_ptr->service_use_count)
2545 			continue;
2546 
2547 		if (service_ptr->srvstate != VCHIQ_SRVSTATE_FREE) {
2548 			service_data[j].fourcc = service_ptr->base.fourcc;
2549 			service_data[j].clientid = service_ptr->client_id;
2550 			service_data[j++].use_count = service_ptr->
2551 							service_use_count;
2552 		}
2553 	}
2554 
2555 	read_unlock_bh(&arm_state->susp_res_lock);
2556 
2557 	vchiq_log_warning(vchiq_susp_log_level,
2558 		"-- Videcore suspend state: %s --",
2559 		suspend_state_names[vc_suspend_state + VC_SUSPEND_NUM_OFFSET]);
2560 	vchiq_log_warning(vchiq_susp_log_level,
2561 		"-- Videcore resume state: %s --",
2562 		resume_state_names[vc_resume_state + VC_RESUME_NUM_OFFSET]);
2563 
2564 	if (only_nonzero)
2565 		vchiq_log_warning(vchiq_susp_log_level, "Too many active "
2566 			"services (%d).  Only dumping up to first %d services "
2567 			"with non-zero use-count", active_services,
2568 			local_max_services);
2569 
2570 	for (i = 0; i < j; i++) {
2571 		vchiq_log_warning(vchiq_susp_log_level,
2572 			"----- %c%c%c%c:%d service count %d %s",
2573 			VCHIQ_FOURCC_AS_4CHARS(service_data[i].fourcc),
2574 			service_data[i].clientid,
2575 			service_data[i].use_count,
2576 			service_data[i].use_count ? nz : "");
2577 	}
2578 	vchiq_log_warning(vchiq_susp_log_level,
2579 		"----- VCHIQ use count count %d", peer_count);
2580 	vchiq_log_warning(vchiq_susp_log_level,
2581 		"--- Overall vchiq instance use count %d", vc_use_count);
2582 
2583 	vchiq_dump_platform_use_state(state);
2584 }
2585 
2586 VCHIQ_STATUS_T
2587 vchiq_check_service(VCHIQ_SERVICE_T *service)
2588 {
2589 	VCHIQ_ARM_STATE_T *arm_state;
2590 	VCHIQ_STATUS_T ret = VCHIQ_ERROR;
2591 
2592 	if (!service || !service->state)
2593 		goto out;
2594 
2595 	vchiq_log_trace(vchiq_susp_log_level, "%s", __func__);
2596 
2597 	arm_state = vchiq_platform_get_arm_state(service->state);
2598 
2599 	read_lock_bh(&arm_state->susp_res_lock);
2600 	if (service->service_use_count)
2601 		ret = VCHIQ_SUCCESS;
2602 	read_unlock_bh(&arm_state->susp_res_lock);
2603 
2604 	if (ret == VCHIQ_ERROR) {
2605 		vchiq_log_error(vchiq_susp_log_level,
2606 			"%s ERROR - %c%c%c%c:%8x service count %d, "
2607 			"state count %d, videocore suspend state %s", __func__,
2608 			VCHIQ_FOURCC_AS_4CHARS(service->base.fourcc),
2609 			service->client_id, service->service_use_count,
2610 			arm_state->videocore_use_count,
2611 			suspend_state_names[arm_state->vc_suspend_state +
2612 						VC_SUSPEND_NUM_OFFSET]);
2613 		vchiq_dump_service_use_state(service->state);
2614 	}
2615 out:
2616 	return ret;
2617 }
2618 
2619 /* stub functions */
2620 void vchiq_on_remote_use_active(VCHIQ_STATE_T *state)
2621 {
2622 	(void)state;
2623 }
2624 
2625 void vchiq_platform_conn_state_changed(VCHIQ_STATE_T *state,
2626 	VCHIQ_CONNSTATE_T oldstate, VCHIQ_CONNSTATE_T newstate)
2627 {
2628 	VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
2629 	vchiq_log_info(vchiq_susp_log_level, "%d: %s->%s", state->id,
2630 		get_conn_state_name(oldstate), get_conn_state_name(newstate));
2631 	if (state->conn_state == VCHIQ_CONNSTATE_CONNECTED) {
2632 		write_lock_bh(&arm_state->susp_res_lock);
2633 		if (!arm_state->first_connect) {
2634 			char threadname[10];
2635 			arm_state->first_connect = 1;
2636 			write_unlock_bh(&arm_state->susp_res_lock);
2637 			snprintf(threadname, sizeof(threadname), "VCHIQka-%d",
2638 				state->id);
2639 			arm_state->ka_thread = vchiq_thread_create(
2640 				&vchiq_keepalive_thread_func,
2641 				(void *)state,
2642 				threadname);
2643 			if (arm_state->ka_thread == NULL) {
2644 				vchiq_log_error(vchiq_susp_log_level,
2645 					"vchiq: FATAL: couldn't create thread %s",
2646 					threadname);
2647 			} else {
2648 				wake_up_process(arm_state->ka_thread);
2649 			}
2650 		} else
2651 			write_unlock_bh(&arm_state->susp_res_lock);
2652 	}
2653 }
2654 
2655 /****************************************************************************
2656 *
2657 *   vchiq_init - called when the module is loaded.
2658 *
2659 ***************************************************************************/
2660 
2661 int __init vchiq_init(void);
2662 int __init
2663 vchiq_init(void)
2664 {
2665 	int err;
2666 
2667 #ifdef notyet
2668 	/* create proc entries */
2669 	err = vchiq_proc_init();
2670 	if (err != 0)
2671 		goto failed_proc_init;
2672 #endif
2673 
2674 	spin_lock_init(&msg_queue_spinlock);
2675 
2676 	err = vchiq_platform_init(&g_state);
2677 	if (err != 0)
2678 		goto failed_platform_init;
2679 
2680 	vchiq_log_info(vchiq_arm_log_level,
2681 		"vchiq: initialised - version %d (min %d)",
2682 		VCHIQ_VERSION, VCHIQ_VERSION_MIN);
2683 
2684 	return 0;
2685 
2686 failed_platform_init:
2687 	vchiq_log_warning(vchiq_arm_log_level, "could not load vchiq");
2688 	return err;
2689 }
2690 
2691 #ifdef notyet
2692 static int vchiq_instance_get_use_count(VCHIQ_INSTANCE_T instance)
2693 {
2694 	VCHIQ_SERVICE_T *service;
2695 	int use_count = 0, i;
2696 	i = 0;
2697 	while ((service = next_service_by_instance(instance->state,
2698 		instance, &i)) != NULL) {
2699 		use_count += service->service_use_count;
2700 		unlock_service(service);
2701 	}
2702 	return use_count;
2703 }
2704 
2705 /* read the per-process use-count */
2706 static int proc_read_use_count(char *page, char **start,
2707 			       off_t off, int count,
2708 			       int *eof, void *data)
2709 {
2710 	VCHIQ_INSTANCE_T instance = data;
2711 	int len, use_count;
2712 
2713 	use_count = vchiq_instance_get_use_count(instance);
2714 	len = snprintf(page+off, count, "%d\n", use_count);
2715 
2716 	return len;
2717 }
2718 
2719 /* add an instance (process) to the proc entries */
2720 static int vchiq_proc_add_instance(VCHIQ_INSTANCE_T instance)
2721 {
2722 	char pidstr[32];
2723 	struct proc_dir_entry *top, *use_count;
2724 	struct proc_dir_entry *clients = vchiq_clients_top();
2725 	int pid = instance->pid;
2726 
2727 	snprintf(pidstr, sizeof(pidstr), "%d", pid);
2728 	top = proc_mkdir(pidstr, clients);
2729 	if (!top)
2730 		goto fail_top;
2731 
2732 	use_count = create_proc_read_entry("use_count",
2733 					   0444, top,
2734 					   proc_read_use_count,
2735 					   instance);
2736 	if (!use_count)
2737 		goto fail_use_count;
2738 
2739 	instance->proc_entry = top;
2740 
2741 	return 0;
2742 
2743 fail_use_count:
2744 	remove_proc_entry(top->name, clients);
2745 fail_top:
2746 	return -ENOMEM;
2747 }
2748 
2749 static void vchiq_proc_remove_instance(VCHIQ_INSTANCE_T instance)
2750 {
2751 	struct proc_dir_entry *clients = vchiq_clients_top();
2752 	remove_proc_entry("use_count", instance->proc_entry);
2753 	remove_proc_entry(instance->proc_entry->name, clients);
2754 }
2755 
2756 #endif
2757 
2758 /****************************************************************************
2759 *
2760 *   vchiq_exit - called when the module is unloaded.
2761 *
2762 ***************************************************************************/
2763 
2764 void vchiq_exit(void);
2765 void
2766 vchiq_exit(void)
2767 {
2768 	vchiq_platform_exit(&g_state);
2769 }
2770