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 /** */
15 /** USBX Component */
16 /** */
17 /** Host Stack */
18 /** */
19 /**************************************************************************/
20 /**************************************************************************/
21
22
23 /* Include necessary system files. */
24
25 #define UX_SOURCE_CODE
26
27 #include "ux_api.h"
28 #include "ux_host_stack.h"
29
30
31 /**************************************************************************/
32 /* */
33 /* FUNCTION RELEASE */
34 /* */
35 /* _ux_host_stack_class_instance_create PORTABLE C */
36 /* 6.1 */
37 /* AUTHOR */
38 /* */
39 /* Chaoqiong Xiao, Microsoft Corporation */
40 /* */
41 /* DESCRIPTION */
42 /* */
43 /* This function creates a new class instance for a class container. */
44 /* The instance of a class is not contained in the class code to */
45 /* reduce the class driver complexity. Rather, each class instance is */
46 /* attached to class container. */
47 /* */
48 /* INPUT */
49 /* */
50 /* class Pointer to class */
51 /* class_instance Pointer to class instance */
52 /* */
53 /* OUTPUT */
54 /* */
55 /* Completion Status */
56 /* */
57 /* CALLS */
58 /* */
59 /* None */
60 /* */
61 /* CALLED BY */
62 /* */
63 /* Application */
64 /* USBX Components */
65 /* */
66 /* RELEASE HISTORY */
67 /* */
68 /* DATE NAME DESCRIPTION */
69 /* */
70 /* 05-19-2020 Chaoqiong Xiao Initial Version 6.0 */
71 /* 09-30-2020 Chaoqiong Xiao Modified comment(s), */
72 /* resulting in version 6.1 */
73 /* */
74 /**************************************************************************/
_ux_host_stack_class_instance_create(UX_HOST_CLASS * host_class,VOID * class_instance)75 UINT _ux_host_stack_class_instance_create(UX_HOST_CLASS *host_class, VOID *class_instance)
76 {
77
78 VOID **current_class_instance;
79
80 /* If trace is enabled, insert this event into the trace buffer. */
81 UX_TRACE_IN_LINE_INSERT(UX_TRACE_HOST_STACK_CLASS_INSTANCE_CREATE, host_class, class_instance, 0, 0, UX_TRACE_HOST_STACK_EVENTS, 0, 0)
82
83 /* If trace is enabled, register this object. */
84 UX_TRACE_OBJECT_REGISTER(UX_TRACE_HOST_OBJECT_TYPE_CLASS_INSTANCE, class_instance, 0, 0, 0)
85
86 /* Start with the first class instance attached to the class container. */
87 current_class_instance = host_class -> ux_host_class_first_instance;
88
89 /* Check if there are any instances attached. */
90 if (current_class_instance == UX_NULL)
91 {
92
93 /* Since it is the first class, attach it to the class container. */
94 host_class -> ux_host_class_first_instance = class_instance;
95
96 /* Return successful completion. */
97 return(UX_SUCCESS);
98 }
99
100 /* Traverse the list of the class instances until we find the last class. */
101 while (*current_class_instance != UX_NULL)
102 {
103
104 /* Point to the next class instance. */
105 current_class_instance = *current_class_instance;
106 }
107
108 /* We have reached the last class, hook the new class to the end. This way, we preserve
109 the chronological order of the class instances. */
110 *current_class_instance = class_instance;
111
112 /* Return successful completion to caller. */
113 return(UX_SUCCESS);
114 }
115
116
