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 Video 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_video.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_video_read_task_function PORTABLE C */
37 /* 6.3.0 */
38 /* AUTHOR */
39 /* */
40 /* Chaoqiong Xiao, Microsoft Corporation */
41 /* */
42 /* DESCRIPTION */
43 /* */
44 /* This function is the background task of the video stream read. */
45 /* */
46 /* It's for standalone mode. */
47 /* */
48 /* INPUT */
49 /* */
50 /* stream Pointer to video stream */
51 /* */
52 /* OUTPUT */
53 /* */
54 /* State machine status */
55 /* UX_STATE_EXIT Device not configured */
56 /* UX_STATE_IDLE No streaming transfer running */
57 /* UX_STATE_WAIT Streaming transfer running */
58 /* */
59 /* CALLS */
60 /* */
61 /* _ux_device_stack_transfer_run Run transfer state machine */
62 /* _ux_utility_memory_copy Copy memory */
63 /* */
64 /* CALLED BY */
65 /* */
66 /* USBX Device Stack */
67 /* */
68 /* RELEASE HISTORY */
69 /* */
70 /* DATE NAME DESCRIPTION */
71 /* */
72 /* 10-31-2022 Chaoqiong Xiao Initial Version 6.2.0 */
73 /* 10-31-2023 Chaoqiong Xiao Modified comment(s), */
74 /* useed zero copy when class */
75 /* owns endpoint buffer, */
76 /* resulting in version 6.3.0 */
77 /* */
78 /**************************************************************************/
_ux_device_class_video_read_task_function(UX_DEVICE_CLASS_VIDEO_STREAM * stream)79 UINT _ux_device_class_video_read_task_function(UX_DEVICE_CLASS_VIDEO_STREAM *stream)
80 {
81 UX_SLAVE_DEVICE *device;
82 UX_SLAVE_ENDPOINT *endpoint;
83 UX_SLAVE_TRANSFER *transfer;
84 UCHAR *next_pos;
85 UX_DEVICE_CLASS_VIDEO_PAYLOAD *next_payload;
86 ULONG max_packet_size;
87 ULONG actual_length;
88 UINT status;
89
90
91 /* Get the pointer to the device. */
92 device = stream -> ux_device_class_video_stream_video -> ux_device_class_video_device;
93
94 /* Check if the device is configured. */
95 if (device -> ux_slave_device_state != UX_DEVICE_CONFIGURED)
96 {
97 stream -> ux_device_class_video_stream_task_state = UX_STATE_EXIT;
98 return(UX_STATE_EXIT);
99 }
100
101 /* Get the endpoint. */
102 endpoint = stream -> ux_device_class_video_stream_endpoint;
103
104 /* No endpoint ready, maybe it's alternate setting 0. */
105 if (endpoint == UX_NULL)
106 return(UX_STATE_IDLE);
107
108 /* Check if background transfer task is started. */
109 if (stream -> ux_device_class_video_stream_task_state == UX_DEVICE_CLASS_VIDEO_STREAM_RW_STOP)
110 return(UX_STATE_IDLE);
111
112 /* Get transfer instance. */
113 transfer = &endpoint -> ux_slave_endpoint_transfer_request;
114
115 /* If not started yet, reset transfer and start polling. */
116 if (stream -> ux_device_class_video_stream_task_state == UX_DEVICE_CLASS_VIDEO_STREAM_RW_START)
117 {
118
119 /* Next state: transfer wait. */
120 stream -> ux_device_class_video_stream_task_state = UX_DEVICE_CLASS_VIDEO_STREAM_RW_WAIT;
121
122 #if UX_DEVICE_ENDPOINT_BUFFER_OWNER == 1
123
124 /* Zero copy: directly use frame buffer. */
125 transfer -> ux_slave_transfer_request_data_pointer = stream ->
126 ux_device_class_video_stream_transfer_pos -> ux_device_class_video_payload_data;
127 #endif
128
129 /* Reset transfer state. */
130 UX_SLAVE_TRANSFER_STATE_RESET(transfer);
131 }
132
133 /* Run transfer state machine. */
134 max_packet_size = endpoint -> ux_slave_endpoint_transfer_request.
135 ux_slave_transfer_request_transfer_length;
136 status = _ux_device_stack_transfer_run(transfer, max_packet_size, max_packet_size);
137
138 /* Error case. */
139 if (status < UX_STATE_NEXT)
140 {
141
142 /* Error on background transfer task start. */
143 stream -> ux_device_class_video_stream_task_state = UX_STATE_RESET;
144 stream -> ux_device_class_video_stream_task_status =
145 transfer -> ux_slave_transfer_request_completion_code;
146
147 /* Error notification! */
148 _ux_system_error_handler(UX_SYSTEM_LEVEL_THREAD, UX_SYSTEM_CONTEXT_CLASS, UX_TRANSFER_ERROR);
149 return(UX_STATE_EXIT);
150 }
151
152 /* Success case. */
153 if (status == UX_STATE_NEXT)
154 {
155
156 /* Next state: start. */
157 stream -> ux_device_class_video_stream_task_state = UX_DEVICE_CLASS_VIDEO_STREAM_RW_START;
158 stream -> ux_device_class_video_stream_task_status =
159 transfer -> ux_slave_transfer_request_completion_code;
160
161 /* Get actual transfer length. */
162 actual_length = transfer -> ux_slave_transfer_request_actual_length;
163
164 /* Frame received, log it. */
165 stream -> ux_device_class_video_stream_transfer_pos -> ux_device_class_video_payload_length = actual_length;
166
167 #if UX_DEVICE_ENDPOINT_BUFFER_OWNER == 1
168
169 /* Zero copy: data already in frame buffer. */
170 #else
171
172 /* Copy data from endpoint buffer. */
173 _ux_utility_memory_copy(stream -> ux_device_class_video_stream_transfer_pos -> ux_device_class_video_payload_data,
174 transfer -> ux_slave_transfer_request_data_pointer,
175 actual_length); /* Use case of memcpy is verified. */
176 #endif
177
178 /* For simple, do not advance the transfer position if there is overflow. */
179 next_pos = (UCHAR *)stream -> ux_device_class_video_stream_transfer_pos;
180 next_pos += stream -> ux_device_class_video_stream_payload_buffer_size;
181 if (next_pos >= stream -> ux_device_class_video_stream_buffer + stream -> ux_device_class_video_stream_buffer_size)
182 next_pos = stream -> ux_device_class_video_stream_buffer;
183 next_payload = (UX_DEVICE_CLASS_VIDEO_PAYLOAD *)next_pos;
184
185 /* Check overflow! */
186 if (next_payload -> ux_device_class_video_payload_length > 0)
187 {
188
189 /* Error notification! */
190 stream -> ux_device_class_video_stream_buffer_error_count ++;
191 _ux_system_error_handler(UX_SYSTEM_LEVEL_THREAD, UX_SYSTEM_CONTEXT_CLASS, UX_BUFFER_OVERFLOW);
192 }
193 else
194
195 /* Update transfer position. */
196 stream -> ux_device_class_video_stream_transfer_pos = next_payload;
197
198 /* Invoke notification callback. */
199 if (stream -> ux_device_class_video_stream_callbacks.ux_device_class_video_stream_payload_done != UX_NULL)
200 stream -> ux_device_class_video_stream_callbacks.ux_device_class_video_stream_payload_done(stream, actual_length);
201 }
202
203 /* Keep waiting. */
204 return(UX_STATE_WAIT);
205 }
206 #endif
207
