1 /***************************************************************************
2 * Copyright (c) 2024 Microsoft Corporation
3 *
4 * This program and the accompanying materials are made available under the
5 * terms of the MIT License which is available at
6 * https://opensource.org/licenses/MIT.
7 *
8 * SPDX-License-Identifier: MIT
9 **************************************************************************/
10
11 /**************************************************************************/
12 /**************************************************************************/
13 /** */
14 /** USBX Component */
15 /** */
16 /** Device Audio Class */
17 /** */
18 /**************************************************************************/
19 /**************************************************************************/
20
21 #define UX_SOURCE_CODE
22
23
24 /* Include necessary system files. */
25
26 #include "ux_api.h"
27 #include "ux_device_class_audio.h"
28 #include "ux_device_stack.h"
29
30
31 #if defined(UX_DEVICE_STANDALONE)
32 /**************************************************************************/
33 /* */
34 /* FUNCTION RELEASE */
35 /* */
36 /* _ux_device_class_audio_write_task_function PORTABLE C */
37 /* 6.3.0 */
38 /* AUTHOR */
39 /* */
40 /* Yajun Xia, Microsoft Corporation */
41 /* */
42 /* DESCRIPTION */
43 /* */
44 /* This function is the background task of the audio stream write. */
45 /* */
46 /* It's for standalone mode. */
47 /* */
48 /* INPUT */
49 /* */
50 /* audio_class Address of audio class */
51 /* container */
52 /* */
53 /* OUTPUT */
54 /* */
55 /* State machine status */
56 /* UX_STATE_EXIT Device not configured */
57 /* UX_STATE_IDLE No streaming transfer running */
58 /* UX_STATE_WAIT Streaming transfer running */
59 /* */
60 /* CALLS */
61 /* */
62 /* _ux_device_stack_transfer_run Run transfer state machine */
63 /* _ux_utility_memory_copy Copy memory */
64 /* */
65 /* CALLED BY */
66 /* */
67 /* USBX Device Stack */
68 /* */
69 /* RELEASE HISTORY */
70 /* */
71 /* DATE NAME DESCRIPTION */
72 /* */
73 /* 10-31-2022 Yajun Xia Initial Version 6.2.0 */
74 /* 10-31-2023 Chaoqiong Xiao Modified comment(s), */
75 /* added a new mode to manage */
76 /* endpoint buffer in classes */
77 /* with zero copy enabled, */
78 /* resulting in version 6.3.0 */
79 /* */
80 /**************************************************************************/
_ux_device_class_audio_write_task_function(UX_DEVICE_CLASS_AUDIO_STREAM * stream)81 UINT _ux_device_class_audio_write_task_function(UX_DEVICE_CLASS_AUDIO_STREAM *stream)
82 {
83 UX_SLAVE_DEVICE *device;
84 UX_SLAVE_ENDPOINT *endpoint;
85 UX_SLAVE_TRANSFER *transfer;
86 UCHAR *next_pos;
87 UX_DEVICE_CLASS_AUDIO_FRAME *next_frame;
88 ULONG transfer_length;
89 ULONG actual_length;
90 UINT status;
91
92
93 /* Get the pointer to the device. */
94 device = stream -> ux_device_class_audio_stream_audio -> ux_device_class_audio_device;
95
96 /* Check if the device is configured. */
97 if (device -> ux_slave_device_state != UX_DEVICE_CONFIGURED)
98 {
99 stream -> ux_device_class_audio_stream_task_state = UX_STATE_EXIT;
100 return(UX_STATE_EXIT);
101 }
102
103 /* Get the endpoint. */
104 endpoint = stream -> ux_device_class_audio_stream_endpoint;
105
106 /* No endpoint ready, maybe it's alternate setting 0. */
107 if (endpoint == UX_NULL)
108 return(UX_STATE_IDLE);
109
110 /* Check if background transfer task is started. */
111 if (stream -> ux_device_class_audio_stream_task_state == UX_DEVICE_CLASS_AUDIO_STREAM_RW_STOP)
112 return(UX_STATE_IDLE);
113
114 /* Get transfer instance. */
115 transfer = &endpoint -> ux_slave_endpoint_transfer_request;
116
117 /* If not started yet, prepare data, reset transfer and start polling. */
118 if (stream -> ux_device_class_audio_stream_task_state == UX_DEVICE_CLASS_AUDIO_STREAM_RW_START)
119 {
120
121 /* Next state: transfer wait. */
122 stream -> ux_device_class_audio_stream_task_state = UX_DEVICE_CLASS_AUDIO_STREAM_RW_WAIT;
123
124 /* Start frame transfer anyway (even ZLP). */
125 transfer_length = stream -> ux_device_class_audio_stream_transfer_pos -> ux_device_class_audio_frame_length;
126
127 #if UX_DEVICE_ENDPOINT_BUFFER_OWNER == 0
128
129 /* Stack owns buffer, copy data to it. */
130 if (transfer_length)
131 _ux_utility_memory_copy(transfer -> ux_slave_transfer_request_data_pointer,
132 stream -> ux_device_class_audio_stream_transfer_pos -> ux_device_class_audio_frame_data, transfer_length); /* Use case of memcpy is verified. */
133 #else
134
135 /* Zero copy: directly use frame buffer to transfer. */
136 transfer -> ux_slave_transfer_request_data_pointer = stream ->
137 ux_device_class_audio_stream_transfer_pos -> ux_device_class_audio_frame_data;
138 #endif
139
140 /* Reset transfer state. */
141 UX_SLAVE_TRANSFER_STATE_RESET(transfer);
142 }
143
144 /* Get current transfer length. */
145 transfer_length = stream -> ux_device_class_audio_stream_transfer_pos -> ux_device_class_audio_frame_length;
146
147 /* Run transfer states. */
148 status = _ux_device_stack_transfer_run(transfer, transfer_length, transfer_length);
149
150 /* Error case. */
151 if (status < UX_STATE_NEXT)
152 {
153
154 /* Error on background transfer task start. */
155 stream -> ux_device_class_audio_stream_task_state = UX_STATE_RESET;
156 stream -> ux_device_class_audio_stream_task_status =
157 transfer -> ux_slave_transfer_request_completion_code;
158
159 /* Error notification! */
160 _ux_system_error_handler(UX_SYSTEM_LEVEL_THREAD, UX_SYSTEM_CONTEXT_CLASS, UX_TRANSFER_ERROR);
161 return(UX_STATE_EXIT);
162 }
163
164 /* Success case. */
165 if (status == UX_STATE_NEXT)
166 {
167
168 /* Next state: start. */
169 stream -> ux_device_class_audio_stream_task_state = UX_DEVICE_CLASS_AUDIO_STREAM_RW_START;
170 stream -> ux_device_class_audio_stream_task_status =
171 transfer -> ux_slave_transfer_request_completion_code;
172
173 /* Frame sent, free it. */
174 stream -> ux_device_class_audio_stream_transfer_pos -> ux_device_class_audio_frame_length = 0;
175
176 /* Get actual transfer length. */
177 actual_length = transfer -> ux_slave_transfer_request_actual_length;
178
179 /* Calculate next position. */
180 next_pos = (UCHAR *)stream -> ux_device_class_audio_stream_transfer_pos;
181 next_pos += stream -> ux_device_class_audio_stream_frame_buffer_size;
182 if (next_pos >= stream -> ux_device_class_audio_stream_buffer + stream -> ux_device_class_audio_stream_buffer_size)
183 next_pos = stream -> ux_device_class_audio_stream_buffer;
184 next_frame = (UX_DEVICE_CLASS_AUDIO_FRAME *)next_pos;
185
186 /* Underflow check! */
187 if (transfer_length)
188 {
189
190 /* Advance position. */
191 stream -> ux_device_class_audio_stream_transfer_pos = next_frame;
192
193 /* Error trap! */
194 if (next_frame -> ux_device_class_audio_frame_length == 0)
195 {
196 _ux_system_error_handler(UX_SYSTEM_LEVEL_THREAD, UX_SYSTEM_CONTEXT_CLASS, UX_BUFFER_OVERFLOW);
197 stream -> ux_device_class_audio_stream_buffer_error_count ++;
198 }
199 }
200 else
201 {
202
203 /* Advance position if next payload available. */
204 if (next_frame -> ux_device_class_audio_frame_length)
205 stream -> ux_device_class_audio_stream_transfer_pos = next_frame;
206 else
207 {
208
209 /* Error trap! */
210 _ux_system_error_handler(UX_SYSTEM_LEVEL_THREAD, UX_SYSTEM_CONTEXT_CLASS, UX_BUFFER_OVERFLOW);
211 stream -> ux_device_class_audio_stream_buffer_error_count ++;
212 }
213 }
214
215 /* Invoke notification callback. */
216 if (stream -> ux_device_class_audio_stream_callbacks.ux_device_class_audio_stream_frame_done != UX_NULL)
217 stream -> ux_device_class_audio_stream_callbacks.ux_device_class_audio_stream_frame_done(stream, actual_length);
218 }
219
220 /* Keep waiting. */
221 return(UX_STATE_WAIT);
222 }
223 #endif
224
225
