Outline ![]()
Files ![]()
loading...
CodeScope![]()
STM32 Libraries and Samples![]()
usbx![]()
common/usbx_host_classes/src/ux_host_class_hid_report_descriptor_get.c
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
/**************************************************************************/
/* */
/* Copyright (c) Microsoft Corporation. All rights reserved. */
/* */
/* This software is licensed under the Microsoft Software License */
/* Terms for Microsoft Azure RTOS. Full text of the license can be */
/* found in the LICENSE file at https://aka.ms/AzureRTOS_EULA */
/* and in the root directory of this software. */
/* */
/**************************************************************************/
/**************************************************************************/
/**************************************************************************/
/** */
/** USBX Component */
/** */
/** HID Class */
/** */
/**************************************************************************/
/**************************************************************************/
/* Include necessary system files. */
#define UX_SOURCE_CODE
#include "ux_api.h"
#include "ux_host_class_hid.h"
#include "ux_host_stack.h"
/**************************************************************************/
/* */
/* FUNCTION RELEASE */
/* */
/* _ux_host_class_hid_report_descriptor_get PORTABLE C */
/* 6.1 */
/* AUTHOR */
/* */
/* Chaoqiong Xiao, Microsoft Corporation */
/* */
/* DESCRIPTION */
/* */
/* This function gets the report descriptor and analyzes it. */
/* */
/* INPUT */
/* */
/* hid Pointer to HID class */
/* length Length of descriptor */
/* */
/* OUTPUT */
/* */
/* Completion Status */
/* */
/* CALLS */
/* */
/* _ux_host_class_hid_global_item_parse Parse global item */
/* _ux_host_class_hid_local_item_parse Parse local item */
/* _ux_host_class_hid_report_item_analyse Analyze report */
/* _ux_host_class_hid_resources_free Free HID resources */
/* _ux_host_stack_transfer_request Process transfer request */
/* _ux_utility_memory_allocate Allocate memory block */
/* _ux_utility_memory_free Release memory block */
/* */
/* CALLED BY */
/* */
/* HID Class */
/* */
/* RELEASE HISTORY */
/* */
/* DATE NAME DESCRIPTION */
/* */
/* 05-19-2020 Chaoqiong Xiao Initial Version 6.0 */
/* 09-30-2020 Chaoqiong Xiao Modified comment(s), */
/* resulting in version 6.1 */
/* */
/**************************************************************************/
UINT _ux_host_class_hid_report_descriptor_get(UX_HOST_CLASS_HID *hid, ULONG length)
{
UX_ENDPOINT *control_endpoint;
UX_TRANSFER *transfer_request;
UCHAR *descriptor;
UCHAR *start_descriptor;
UX_HOST_CLASS_HID_ITEM item;
UINT status;
/* We need to get the default control endpoint transfer request pointer. */
control_endpoint = &hid -> ux_host_class_hid_device -> ux_device_control_endpoint;
transfer_request = &control_endpoint -> ux_endpoint_transfer_request;
/* Need to allocate memory for the report descriptor. */
descriptor = _ux_utility_memory_allocate(UX_SAFE_ALIGN, UX_CACHE_SAFE_MEMORY, length);
if (descriptor == UX_NULL)
return(UX_MEMORY_INSUFFICIENT);
/* We need to save the descriptor starting address. */
start_descriptor = descriptor;
/* Create a transfer_request for the GET_DESCRIPTOR request */
transfer_request -> ux_transfer_request_data_pointer = descriptor;
transfer_request -> ux_transfer_request_requested_length = length;
transfer_request -> ux_transfer_request_function = UX_GET_DESCRIPTOR;
transfer_request -> ux_transfer_request_type = UX_REQUEST_IN | UX_REQUEST_TYPE_STANDARD | UX_REQUEST_TARGET_INTERFACE;
transfer_request -> ux_transfer_request_value = UX_HOST_CLASS_HID_REPORT_DESCRIPTOR << 8;
transfer_request -> ux_transfer_request_index = hid -> ux_host_class_hid_interface -> ux_interface_descriptor.bInterfaceNumber;
/* Send request to HCD layer. */
status = _ux_host_stack_transfer_request(transfer_request);
/* Check for correct transfer and entire descriptor returned. */
if ((status == UX_SUCCESS) && (transfer_request -> ux_transfer_request_actual_length == length))
{
/* Parse the report descriptor and build the report items. */
while (length)
{
/* Get one item from the report and analyze it. */
_ux_host_class_hid_report_item_analyse(descriptor, &item);
/* Point the descriptor right after the item identifier. */
descriptor += item.ux_host_class_hid_item_report_format;
/* Process relative to the item type. */
switch (item.ux_host_class_hid_item_report_type)
{
case UX_HOST_CLASS_HID_TYPE_GLOBAL:
/* This is a global item. */
status = _ux_host_class_hid_global_item_parse(hid, &item, descriptor);
break;
case UX_HOST_CLASS_HID_TYPE_MAIN:
/* This is a main item. */
status = _ux_host_class_hid_main_item_parse(hid, &item, descriptor);
break;
case UX_HOST_CLASS_HID_TYPE_LOCAL:
/* This is a local item. */
status = _ux_host_class_hid_local_item_parse(hid, &item, descriptor);
break;
default:
/* This is a reserved item, meaning it shouldn't be used! */
/* Set status to error. The check after this switch statement
will handle the rest. */
status = UX_DESCRIPTOR_CORRUPTED;
break;
}
/* Recheck the status code. */
if (status != UX_SUCCESS)
{
break;
}
/* Jump to the next item. */
descriptor += item.ux_host_class_hid_item_report_length;
/* Verify that the report descriptor is not corrupted. */
if (length < item.ux_host_class_hid_item_report_length)
{
/* Return error status. */
status = (UX_DESCRIPTOR_CORRUPTED);
break;
}
/* Adjust the length. */
length -= (ULONG)(item.ux_host_class_hid_item_report_length + item.ux_host_class_hid_item_report_format);
}
}
else
/* Descriptor length error! */
status = UX_DESCRIPTOR_CORRUPTED;
if (status != UX_SUCCESS)
{
/* Error trap. */
_ux_system_error_handler(UX_SYSTEM_LEVEL_THREAD, UX_SYSTEM_CONTEXT_CLASS, UX_DESCRIPTOR_CORRUPTED);
/* If trace is enabled, insert this event into the trace buffer. */
UX_TRACE_IN_LINE_INSERT(UX_TRACE_ERROR, UX_DESCRIPTOR_CORRUPTED, descriptor, 0, 0, UX_TRACE_ERRORS, 0, 0)
/* The descriptor is corrupted! */
_ux_host_class_hid_resources_free(hid);
}
/* Free used resources. */
_ux_utility_memory_free(start_descriptor);
/* Return completion status. */
return(status);
}