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_terminal_get PORTABLE C */
38 /* 6.1 */
39 /* AUTHOR */
40 /* */
41 /* Chaoqiong Xiao, Microsoft Corporation */
42 /* */
43 /* DESCRIPTION */
44 /* */
45 /* This function finds the input terminal in the config descriptor. */
46 /* */
47 /* INPUT */
48 /* */
49 /* video Pointer to video class */
50 /* */
51 /* OUTPUT */
52 /* */
53 /* Completion Status */
54 /* */
55 /* CALLS */
56 /* */
57 /* _ux_system_error_handler System error log */
58 /* _ux_utility_descriptor_parse Parse descriptor */
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_terminal_get(UX_HOST_CLASS_VIDEO * video)73 UINT _ux_host_class_video_input_terminal_get(UX_HOST_CLASS_VIDEO *video)
74 {
75
76 UCHAR *descriptor;
77 UX_INTERFACE_DESCRIPTOR interface_descriptor;
78 UX_HOST_CLASS_VIDEO_INPUT_TERMINAL_DESCRIPTOR input_terminal_descriptor;
79 ULONG total_descriptor_length;
80 ULONG descriptor_length;
81 ULONG descriptor_type;
82 ULONG descriptor_subtype;
83 ULONG interface_found;
84
85
86 /* Get the descriptor to the selected format. */
87 descriptor = video -> ux_host_class_video_configuration_descriptor;
88 total_descriptor_length = video -> ux_host_class_video_configuration_descriptor_length;
89
90 /* Haven't found it yet. */
91 interface_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 descriptor type. */
116 switch (descriptor_type)
117 {
118
119 case UX_INTERFACE_DESCRIPTOR_ITEM:
120
121 /* Parse the interface descriptor and make it machine independent. */
122 _ux_utility_descriptor_parse(descriptor, _ux_system_interface_descriptor_structure,
123 UX_INTERFACE_DESCRIPTOR_ENTRIES, (UCHAR *) &interface_descriptor);
124
125 /* Ensure we have the correct interface for Video Control. */
126 if ((interface_descriptor.bInterfaceClass == UX_HOST_CLASS_VIDEO_CLASS) &&
127 (interface_descriptor.bInterfaceSubClass == UX_HOST_CLASS_VIDEO_SUBCLASS_CONTROL))
128 {
129
130 /* Mark we have found it. */
131 interface_found = UX_TRUE;
132
133 /* Get the interface number of this descriptor and save it in the video
134 instance. This will be useful to program the video controls. */
135 video -> ux_host_class_video_control_interface_number = interface_descriptor.bInterfaceNumber;
136 }
137 else
138 {
139
140 /* Haven't found it. */
141 interface_found = UX_FALSE;
142 }
143 break;
144
145
146 case UX_HOST_CLASS_VIDEO_CS_INTERFACE:
147
148 /* First make sure we have found the correct generic interface descriptor. */
149 if ((interface_found == UX_TRUE) && (descriptor_subtype == UX_HOST_CLASS_VIDEO_VC_INPUT_TERMINAL))
150 {
151
152 /* Parse the interface descriptor and make it machine independent. */
153 _ux_utility_descriptor_parse(descriptor, _ux_system_class_video_input_terminal_descriptor_structure,
154 UX_HOST_CLASS_VIDEO_INPUT_TERMINAL_DESCRIPTOR_ENTRIES, (UCHAR *) &input_terminal_descriptor);
155
156 /* Save the video terminal ID. */
157 video -> ux_host_class_video_terminal_id = input_terminal_descriptor.bTerminalID;
158
159 /* Save the video terminal type. */
160 video -> ux_host_class_video_terminal_type = input_terminal_descriptor.wTerminalType;
161
162
163 /* We are done here. */
164 return(UX_SUCCESS);
165 }
166
167 break;
168 }
169
170 /* Verify if the descriptor is still valid. */
171 if (descriptor_length > total_descriptor_length)
172 {
173
174 /* Error trap. */
175 _ux_system_error_handler(UX_SYSTEM_LEVEL_THREAD, UX_SYSTEM_CONTEXT_CLASS, UX_DESCRIPTOR_CORRUPTED);
176
177 /* If trace is enabled, insert this event into the trace buffer. */
178 //UX_TRACE_IN_LINE_INSERT(UX_TRACE_ERROR, UX_DESCRIPTOR_CORRUPTED, descriptor, 0, 0, UX_TRACE_ERRORS, 0, 0)
179
180 return(UX_DESCRIPTOR_CORRUPTED);
181 }
182
183 /* Jump to the next descriptor if we have not reached the end. */
184 descriptor += descriptor_length;
185
186 /* And adjust the length left to parse in the descriptor. */
187 total_descriptor_length -= descriptor_length;
188 }
189
190 /* Error trap. */
191 _ux_system_error_handler(UX_SYSTEM_LEVEL_THREAD, UX_SYSTEM_CONTEXT_CLASS, UX_HOST_CLASS_VIDEO_WRONG_TYPE);
192
193 /* We get here when either the report descriptor has a problem or we could
194 not find the right video device. */
195 return(UX_HOST_CLASS_VIDEO_WRONG_TYPE);
196 }
197
198
