1 /*--------------------------------------------------------------------------
2 Copyright (c) 2010-2013, The Linux Foundation. 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 are met:
6 * Redistributions of source code must retain the above copyright
7 notice, this list of conditions and the following disclaimer.
8 * Redistributions in binary form must reproduce the above copyright
9 notice, this list of conditions and the following disclaimer in the
10 documentation and/or other materials provided with the distribution.
11 * Neither the name of The Linux Foundation nor
12 the names of its contributors may be used to endorse or promote
13 products derived from this software without specific prior written
14 permission.
15
16 THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
17 AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
19 NON-INFRINGEMENT ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
20 CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
21 EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
22 PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
23 OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
24 WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
25 OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
26 ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 --------------------------------------------------------------------------*/
28 #include "message_queue.h"
29
check_if_queue_empty(unsigned int queuetocheck,void * queuecontext)30 int check_if_queue_empty ( unsigned int queuetocheck, void* queuecontext )
31 {
32 struct video_queue_context *ptr_q = NULL;
33
34 /*
35 * queuetocheck - 0 command queue
36 * queuetocheck - 1 data queue
37 */
38 if ( queuecontext == NULL || (queuetocheck > 1 ) ) {
39 return 1;
40 }
41
42 ptr_q = (struct video_queue_context *)queuecontext;
43
44 if (queuetocheck == 0) {
45 if (ptr_q->read_comq == ptr_q->write_comq) {
46 return 1;
47 }
48 } else if (queuetocheck == 1) {
49 if (ptr_q->write_dataq == ptr_q->read_dataq) {
50 return 1;
51 }
52 }
53
54 return 0;
55 }
56
57
58
queue_get_cmd(void * queuecontext)59 struct video_msgq * queue_get_cmd (void* queuecontext ) {
60 struct video_queue_context *ptr_q = NULL;
61 struct video_msgq *pitem = NULL;
62
63 if ( NULL == queuecontext ) {
64 printf("queue_get_cmd: Invalid Input parameter");
65 return NULL;
66 }
67
68 ptr_q = (struct video_queue_context *)queuecontext;
69
70 /* Wait on the semaphore till it is released */
71 sem_wait(&ptr_q->sem_message);
72
73 /* Lock the mutex to protect the critical section */
74 pthread_mutex_lock(&ptr_q->mutex);
75
76 if (ptr_q->read_comq != ptr_q->write_comq) {
77 pitem = &ptr_q->ptr_cmdq [ptr_q->read_comq];
78 ptr_q->read_comq = (ptr_q->read_comq + 1) % \
79 ptr_q->commandq_size;
80 } else if (ptr_q->write_dataq != ptr_q->read_dataq) {
81 pitem = &ptr_q->ptr_dataq [ptr_q->read_dataq];
82 ptr_q->read_dataq = (ptr_q->read_dataq + 1) % \
83 ptr_q->dataq_size;
84 }
85
86 /* Unlock the mutex to release the critical section */
87 pthread_mutex_unlock(&ptr_q->mutex);
88
89 return pitem;
90 }
91
92
queue_post_cmdq(void * queuecontext,struct video_msgq * pitem)93 int queue_post_cmdq ( void* queuecontext,
94 struct video_msgq *pitem
95 )
96 {
97 struct video_queue_context *ptr_q = NULL;
98
99 if (pitem == NULL || queuecontext == NULL) {
100 return -1;
101 }
102
103 ptr_q = (struct video_queue_context *)queuecontext;
104
105 /* Lock the mutex to protect the critical section */
106 pthread_mutex_lock(&ptr_q->mutex);
107
108 if ((ptr_q->write_comq + 1) % ptr_q->commandq_size == ptr_q->read_comq) {
109 printf("QUEUE is FULL");
110 /* Unlock the mutex to release the critical section */
111 pthread_mutex_unlock(&ptr_q->mutex);
112 return 0;
113 } else {
114 /* Store the command in the Message Queue & increment write offset */
115 memcpy ( &ptr_q->ptr_cmdq [ptr_q->write_comq],pitem, \
116 sizeof (struct video_msgq));
117 ptr_q->write_comq = (ptr_q->write_comq + 1) % ptr_q->commandq_size;
118 }
119
120 /* Unlock the mutex to release the critical section */
121 pthread_mutex_unlock(&ptr_q->mutex);
122
123 /* Post the semaphore */
124 sem_post(&ptr_q->sem_message);
125 return 1;
126 }
127
128
queue_post_dataq(void * queuecontext,struct video_msgq * pitem)129 int queue_post_dataq ( void *queuecontext,
130 struct video_msgq *pitem
131 )
132 {
133 struct video_queue_context *ptr_q = NULL;
134
135 if (pitem == NULL || queuecontext == NULL) {
136 return -1;
137 }
138
139 ptr_q = (struct video_queue_context *)queuecontext;
140
141 /* Lock the mutex to protect the critical section */
142 pthread_mutex_lock(&ptr_q->mutex);
143
144 if ((ptr_q->write_dataq + 1) % ptr_q->dataq_size == ptr_q->read_dataq) {
145 printf("QUEUE is FULL");
146 /* Unlock the mutex to release the critical section */
147 pthread_mutex_unlock(&ptr_q->mutex);
148 return 0;
149 } else {
150 /* Store the command in the Message Queue & increment write offset */
151 memcpy ( &ptr_q->ptr_dataq [ptr_q->write_dataq],pitem, \
152 sizeof (struct video_msgq));
153 ptr_q->write_dataq = (ptr_q->write_dataq + 1) % ptr_q->dataq_size;
154 }
155
156 /* Unlock the mutex to release the critical section */
157 pthread_mutex_unlock(&ptr_q->mutex);
158
159 /* Post the semaphore */
160 sem_post(&ptr_q->sem_message);
161 return 1;
162
163 }
164