1 /**************************************************************************/
2 /* */
3 /* Copyright (c) Microsoft Corporation. All rights reserved. */
4 /* */
5 /* This software is licensed under the Microsoft Software License */
6 /* Terms for Microsoft Azure RTOS. Full text of the license can be */
7 /* found in the LICENSE file at https://aka.ms/AzureRTOS_EULA */
8 /* and in the root directory of this software. */
9 /* */
10 /**************************************************************************/
11
12 /**************************************************************************/
13 /**************************************************************************/
14 /** */
15 /** USBX Component */
16 /** */
17 /** Device Audio Class */
18 /** */
19 /**************************************************************************/
20 /**************************************************************************/
21
22 #define UX_SOURCE_CODE
23
24
25 /* Include necessary system files. */
26
27 #include "ux_api.h"
28 #include "ux_device_class_audio.h"
29 #include "ux_device_stack.h"
30
31
32 /**************************************************************************/
33 /* */
34 /* FUNCTION RELEASE */
35 /* */
36 /* _ux_device_class_audio_sample_read16 PORTABLE C */
37 /* 6.2.1 */
38 /* AUTHOR */
39 /* */
40 /* Chaoqiong Xiao, Microsoft Corporation */
41 /* */
42 /* DESCRIPTION */
43 /* */
44 /* This function reads 16-bit sample value from the Audio class. */
45 /* */
46 /* INPUT */
47 /* */
48 /* stream Address of audio stream */
49 /* instance */
50 /* buffer Pointer to buffer to save */
51 /* sample data */
52 /* */
53 /* OUTPUT */
54 /* */
55 /* None */
56 /* */
57 /* CALLS */
58 /* */
59 /* */
60 /* CALLED BY */
61 /* */
62 /* Application */
63 /* */
64 /* RELEASE HISTORY */
65 /* */
66 /* DATE NAME DESCRIPTION */
67 /* */
68 /* 05-19-2020 Chaoqiong Xiao Initial Version 6.0 */
69 /* 09-30-2020 Chaoqiong Xiao Modified comment(s), */
70 /* resulting in version 6.1 */
71 /* 03-08-2023 Chaoqiong Xiao Modified comment(s), */
72 /* resulting in version 6.2.1 */
73 /* */
74 /**************************************************************************/
_ux_device_class_audio_sample_read16(UX_DEVICE_CLASS_AUDIO_STREAM * stream,USHORT * buffer)75 UINT _ux_device_class_audio_sample_read16(UX_DEVICE_CLASS_AUDIO_STREAM *stream,
76 USHORT *buffer)
77 {
78
79 UX_SLAVE_ENDPOINT *endpoint;
80 UX_SLAVE_DEVICE *device;
81 UCHAR *sample_ptr;
82 UCHAR *next_frame_buffer;
83 ULONG next_frame_sample;
84
85
86 /* Get the pointer to the device. */
87 device = &_ux_system_slave -> ux_system_slave_device;
88
89 /* As long as the device is in the CONFIGURED state. */
90 if (device -> ux_slave_device_state != UX_DEVICE_CONFIGURED)
91 {
92
93 /* Cannot proceed with command, the interface is down. */
94 return(UX_CONFIGURATION_HANDLE_UNKNOWN);
95 }
96
97 /* Check if endpoint is available. */
98 endpoint = stream -> ux_device_class_audio_stream_endpoint;
99 if (endpoint == UX_NULL)
100 return(UX_ERROR);
101
102 /* Check if endpoint direction is OK. */
103 if ((endpoint -> ux_slave_endpoint_descriptor.bEndpointAddress & UX_ENDPOINT_DIRECTION) != UX_ENDPOINT_OUT)
104 return(UX_ERROR);
105
106 /* Underflow!! */
107 if (stream -> ux_device_class_audio_stream_access_pos -> ux_device_class_audio_frame_length == 0)
108 {
109 return(UX_BUFFER_OVERFLOW);
110 }
111
112 /* Try to read a sample. */
113 sample_ptr = stream -> ux_device_class_audio_stream_access_pos -> ux_device_class_audio_frame_data +
114 stream -> ux_device_class_audio_stream_access_pos -> ux_device_class_audio_frame_pos;
115 if (buffer)
116 *buffer = *(USHORT *)(sample_ptr);
117
118 /* Update sample read state. */
119 next_frame_sample = stream -> ux_device_class_audio_stream_access_pos -> ux_device_class_audio_frame_pos + 2;
120 if (next_frame_sample >= stream -> ux_device_class_audio_stream_access_pos -> ux_device_class_audio_frame_length)
121 {
122
123 /* Set frame length to 0 to indicate no data. */
124 stream -> ux_device_class_audio_stream_access_pos -> ux_device_class_audio_frame_length = 0;
125
126 /* Move to next frame buffer. */
127 next_frame_sample = 0;
128
129 /* Move frame if it's not the last one. */
130 if (stream -> ux_device_class_audio_stream_access_pos != stream -> ux_device_class_audio_stream_transfer_pos)
131 {
132 next_frame_buffer = (UCHAR *)stream -> ux_device_class_audio_stream_access_pos;
133 next_frame_buffer += stream -> ux_device_class_audio_stream_frame_buffer_size;
134 if (next_frame_buffer >= stream -> ux_device_class_audio_stream_buffer + stream -> ux_device_class_audio_stream_buffer_size)
135 next_frame_buffer = stream -> ux_device_class_audio_stream_buffer;
136 stream -> ux_device_class_audio_stream_access_pos = (UX_DEVICE_CLASS_AUDIO_FRAME *)next_frame_buffer;
137 }
138 }
139
140 /* Update next sample position. */
141 stream -> ux_device_class_audio_stream_access_pos -> ux_device_class_audio_frame_pos = next_frame_sample;
142
143 return(UX_SUCCESS);
144 }
145
146
147 /**************************************************************************/
148 /* */
149 /* FUNCTION RELEASE */
150 /* */
151 /* _uxe_device_class_audio_sample_read16 PORTABLE C */
152 /* 6.2.1 */
153 /* AUTHOR */
154 /* */
155 /* Chaoqiong Xiao, Microsoft Corporation */
156 /* */
157 /* DESCRIPTION */
158 /* */
159 /* This function checks errors in reading 16-bit sample function call. */
160 /* */
161 /* INPUT */
162 /* */
163 /* stream Address of audio stream */
164 /* instance */
165 /* buffer Pointer to buffer to save */
166 /* sample data */
167 /* */
168 /* OUTPUT */
169 /* */
170 /* None */
171 /* */
172 /* CALLS */
173 /* */
174 /* _ux_device_class_audio_sample_read16 Read 16-bit sample */
175 /* */
176 /* CALLED BY */
177 /* */
178 /* Application */
179 /* */
180 /* RELEASE HISTORY */
181 /* */
182 /* DATE NAME DESCRIPTION */
183 /* */
184 /* 03-08-2023 Chaoqiong Xiao Initial Version 6.2.1 */
185 /* */
186 /**************************************************************************/
_uxe_device_class_audio_sample_read16(UX_DEVICE_CLASS_AUDIO_STREAM * stream,USHORT * buffer)187 UINT _uxe_device_class_audio_sample_read16(UX_DEVICE_CLASS_AUDIO_STREAM *stream,
188 USHORT *buffer)
189 {
190
191 /* Sanity check. */
192 if (stream == UX_NULL)
193 return(UX_INVALID_PARAMETER);
194
195 /* Read 16-bit sample. */
196 return(_ux_device_class_audio_sample_read16(stream, buffer));
197 }
198
