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 /** */
16 /** USBX Component */
17 /** */
18 /** Video Class */
19 /** */
20 /**************************************************************************/
21 /**************************************************************************/
22
23
24 /* Include necessary system files. */
25
26 #define UX_SOURCE_CODE
27
28 #include "ux_api.h"
29 #include "ux_host_class_video.h"
30 #include "ux_host_stack.h"
31
32
33 /**************************************************************************/
34 /* */
35 /* FUNCTION RELEASE */
36 /* */
37 /* _ux_host_class_video_input_format_get PORTABLE C */
38 /* 6.1 */
39 /* AUTHOR */
40 /* */
41 /* Chaoqiong Xiao, Microsoft Corporation */
42 /* */
43 /* DESCRIPTION */
44 /* */
45 /* This function finds the input format(s) for the input terminal. */
46 /* */
47 /* INPUT */
48 /* */
49 /* video Pointer to video class */
50 /* */
51 /* OUTPUT */
52 /* */
53 /* Completion Status */
54 /* */
55 /* CALLS */
56 /* */
57 /* _ux_utility_descriptor_parse Parse descriptor */
58 /* _ux_system_error_handler Log system error */
59 /* */
60 /* CALLED BY */
61 /* */
62 /* Video Class */
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 /* */
72 /**************************************************************************/
_ux_host_class_video_input_format_get(UX_HOST_CLASS_VIDEO * video)73 UINT _ux_host_class_video_input_format_get(UX_HOST_CLASS_VIDEO *video)
74 {
75
76 UCHAR *descriptor;
77 UX_INTERFACE_DESCRIPTOR interface_descriptor;
78 UX_HOST_CLASS_VIDEO_INPUT_HEADER_DESCRIPTOR input_header_descriptor;
79 ULONG total_descriptor_length;
80 ULONG descriptor_length;
81 ULONG descriptor_type;
82 ULONG descriptor_subtype;
83 ULONG descriptor_found;
84
85
86 /* Get the descriptor to the entire configuration. */
87 descriptor = video -> ux_host_class_video_configuration_descriptor;
88 total_descriptor_length = video -> ux_host_class_video_configuration_descriptor_length;
89
90 /* Default is Interface descriptor not yet found. */
91 descriptor_found = UX_FALSE;
92
93 /* Scan the descriptor for the Video Streaming interface. */
94 while (total_descriptor_length)
95 {
96
97 /* Gather the length, type and subtype of the descriptor. */
98 descriptor_length = *descriptor;
99 descriptor_type = *(descriptor + 1);
100 descriptor_subtype = *(descriptor + 2);
101
102 /* Make sure this descriptor has at least the minimum length. */
103 if (descriptor_length < 3)
104 {
105
106 /* Error trap. */
107 _ux_system_error_handler(UX_SYSTEM_LEVEL_THREAD, UX_SYSTEM_CONTEXT_CLASS, UX_DESCRIPTOR_CORRUPTED);
108
109 /* If trace is enabled, insert this event into the trace buffer. */
110 //UX_TRACE_IN_LINE_INSERT(UX_TRACE_ERROR, UX_DESCRIPTOR_CORRUPTED, descriptor, 0, 0, UX_TRACE_ERRORS, 0, 0)
111
112 return(UX_DESCRIPTOR_CORRUPTED);
113 }
114
115 /* Process relative to the descriptor type. */
116 switch (descriptor_type)
117 {
118
119
120 case UX_INTERFACE_DESCRIPTOR_ITEM:
121
122 /* Parse the interface descriptor and make it machine independent. */
123 _ux_utility_descriptor_parse(descriptor, _ux_system_interface_descriptor_structure,
124 UX_INTERFACE_DESCRIPTOR_ENTRIES, (UCHAR *) &interface_descriptor);
125
126 /* Ensure we have the correct interface for Video Streaming. */
127 if ((interface_descriptor.bInterfaceClass == UX_HOST_CLASS_VIDEO_CLASS) &&
128 (interface_descriptor.bInterfaceSubClass == UX_HOST_CLASS_VIDEO_SUBCLASS_STREAMING))
129 {
130
131 /* Mark we have found it. */
132 descriptor_found = UX_TRUE;
133 }
134 else
135 {
136
137 descriptor_found = UX_FALSE;
138 }
139 break;
140
141
142 case UX_HOST_CLASS_VIDEO_CS_INTERFACE:
143
144 /* First make sure we have found the correct generic interface descriptor. */
145 if (descriptor_found == UX_TRUE)
146 {
147
148 /* Check the sub type. */
149 switch (descriptor_subtype)
150 {
151
152
153 case UX_HOST_CLASS_VIDEO_VS_INPUT_HEADER:
154
155 /* Make the descriptor machine independent. */
156 _ux_utility_descriptor_parse(descriptor, _ux_system_class_video_input_header_descriptor_structure,
157 UX_HOST_CLASS_VIDEO_INPUT_HEADER_DESCRIPTOR_ENTRIES, (UCHAR *) &input_header_descriptor);
158
159 /* Get the number of formats. */
160 video -> ux_host_class_video_number_formats = input_header_descriptor.bNumFormats;
161
162 /* Get the length of formats. */
163 video -> ux_host_class_video_length_formats = input_header_descriptor.wTotalLength;
164
165 /* Save the descriptor where the formats reside. */
166 video -> ux_host_class_video_format_address = descriptor;
167
168 /* We are done here. */
169 return(UX_SUCCESS);
170
171 }
172 }
173 break;
174 }
175
176 /* Verify if the descriptor is still valid. */
177 if (descriptor_length > total_descriptor_length)
178 {
179
180 /* Error trap. */
181 _ux_system_error_handler(UX_SYSTEM_LEVEL_THREAD, UX_SYSTEM_CONTEXT_CLASS, UX_DESCRIPTOR_CORRUPTED);
182
183 /* If trace is enabled, insert this event into the trace buffer. */
184 //UX_TRACE_IN_LINE_INSERT(UX_TRACE_ERROR, UX_DESCRIPTOR_CORRUPTED, descriptor, 0, 0, UX_TRACE_ERRORS, 0, 0)
185
186 return(UX_DESCRIPTOR_CORRUPTED);
187 }
188
189 /* Jump to the next descriptor if we have not reached the end. */
190 descriptor += descriptor_length;
191
192 /* And adjust the length left to parse in the descriptor. */
193 total_descriptor_length -= descriptor_length;
194 }
195
196 /* Error trap. */
197 _ux_system_error_handler(UX_SYSTEM_LEVEL_THREAD, UX_SYSTEM_CONTEXT_CLASS, UX_HOST_CLASS_VIDEO_WRONG_TYPE);
198
199 /* We get here when either the report descriptor has a problem or we could
200 not find the right video device. */
201 return(UX_HOST_CLASS_VIDEO_WRONG_TYPE);
202 }
203
204
