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 "vchiq_connected.h"
35#include "vchiq_core.h"
36
37#define  MAX_CALLBACKS  10
38
39static   int                        g_connected;
40static   int                        g_num_deferred_callbacks;
41static   VCHIQ_CONNECTED_CALLBACK_T g_deferred_callback[MAX_CALLBACKS];
42static   int                        g_once_init;
43static   struct mutex               g_connected_mutex;
44
45/****************************************************************************
46*
47* Function to initialize our lock.
48*
49***************************************************************************/
50
51static void connected_init(void)
52{
53	if (!g_once_init) {
54		lmutex_init(&g_connected_mutex);
55		g_once_init = 1;
56	}
57}
58
59/****************************************************************************
60*
61* This function is used to defer initialization until the vchiq stack is
62* initialized. If the stack is already initialized, then the callback will
63* be made immediately, otherwise it will be deferred until
64* vchiq_call_connected_callbacks is called.
65*
66***************************************************************************/
67
68void vchiq_add_connected_callback(VCHIQ_CONNECTED_CALLBACK_T callback)
69{
70	connected_init();
71
72	if (lmutex_lock_interruptible(&g_connected_mutex) != 0)
73		return;
74
75	if (g_connected)
76		/* We're already connected. Call the callback immediately. */
77
78		callback();
79	else {
80		if (g_num_deferred_callbacks >= MAX_CALLBACKS)
81			vchiq_log_error(vchiq_core_log_level,
82				"There are already %d callbacks registered - "
83				"please increase MAX_CALLBACKS",
84				g_num_deferred_callbacks);
85		else {
86			g_deferred_callback[g_num_deferred_callbacks] =
87				callback;
88			g_num_deferred_callbacks++;
89		}
90	}
91	lmutex_unlock(&g_connected_mutex);
92}
93
94/****************************************************************************
95*
96* This function is called by the vchiq stack once it has been connected to
97* the videocore and clients can start to use the stack.
98*
99***************************************************************************/
100
101void vchiq_call_connected_callbacks(void)
102{
103	int i;
104
105	connected_init();
106
107	if (lmutex_lock_interruptible(&g_connected_mutex) != 0)
108		return;
109
110	for (i = 0; i <  g_num_deferred_callbacks; i++)
111		g_deferred_callback[i]();
112
113	g_num_deferred_callbacks = 0;
114	g_connected = 1;
115	lmutex_unlock(&g_connected_mutex);
116}
117EXPORT_SYMBOL(vchiq_add_connected_callback);
118