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 /** Host Stack */
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_stack.h"
30
31
32 /**************************************************************************/
33 /* */
34 /* FUNCTION RELEASE */
35 /* */
36 /* _ux_host_stack_configuration_descriptor_parse PORTABLE C */
37 /* 6.1 */
38 /* AUTHOR */
39 /* */
40 /* Chaoqiong Xiao, Microsoft Corporation */
41 /* */
42 /* DESCRIPTION */
43 /* */
44 /* This function reads the entire configuration descriptor and */
45 /* enumerates the interfaces, binds the interface to a class driver... */
46 /* if the device has multiple configurations, we read all the */
47 /* configurations but do not instantiate any configuration. Rather we */
48 /* let a class driver do the work. */
49 /* */
50 /* INPUT */
51 /* */
52 /* device Pointer to device */
53 /* configuration Pointer to configuration */
54 /* configuration_index Index of configuration */
55 /* */
56 /* OUTPUT */
57 /* */
58 /* Completion Status */
59 /* */
60 /* CALLS */
61 /* */
62 /* _ux_host_stack_interfaces_scan Scan host interfaces */
63 /* _ux_host_stack_transfer_request Process transfer request */
64 /* _ux_utility_memory_allocate Allocate block of memory */
65 /* _ux_utility_memory_free Free block of memory */
66 /* */
67 /* CALLED BY */
68 /* */
69 /* USBX Components */
70 /* */
71 /* RELEASE HISTORY */
72 /* */
73 /* DATE NAME DESCRIPTION */
74 /* */
75 /* 05-19-2020 Chaoqiong Xiao Initial Version 6.0 */
76 /* 09-30-2020 Chaoqiong Xiao Modified comment(s), */
77 /* resulting in version 6.1 */
78 /* */
79 /**************************************************************************/
_ux_host_stack_configuration_descriptor_parse(UX_DEVICE * device,UX_CONFIGURATION * configuration,UINT configuration_index)80 UINT _ux_host_stack_configuration_descriptor_parse(UX_DEVICE *device, UX_CONFIGURATION *configuration,
81 UINT configuration_index)
82 {
83
84 UX_TRANSFER *transfer_request;
85 UINT status;
86 UCHAR *descriptor;
87 UX_ENDPOINT *control_endpoint;
88 ULONG total_configuration_length;
89
90
91 /* Retrieve the pointer to the control endpoint and its transfer_request. */
92 control_endpoint = &device -> ux_device_control_endpoint;
93 transfer_request = &control_endpoint -> ux_endpoint_transfer_request;
94
95 /* Retrieve the size of all the configuration descriptor. */
96 total_configuration_length = configuration -> ux_configuration_descriptor.wTotalLength;
97
98 /* Allocate enough memory to read all descriptors attached to this configuration. */
99 descriptor = _ux_utility_memory_allocate(UX_SAFE_ALIGN, UX_CACHE_SAFE_MEMORY, total_configuration_length);
100
101 /* Determine if the memory was allocated. */
102 if (descriptor == UX_NULL)
103 {
104
105 /* No, return an error. */
106 return(UX_MEMORY_INSUFFICIENT);
107 }
108 else
109 {
110
111 /* Create a transfer_request for the GET_DESCRIPTOR request. */
112 transfer_request -> ux_transfer_request_data_pointer = descriptor;
113 transfer_request -> ux_transfer_request_requested_length = total_configuration_length;
114 transfer_request -> ux_transfer_request_function = UX_GET_DESCRIPTOR;
115 transfer_request -> ux_transfer_request_type = UX_REQUEST_IN | UX_REQUEST_TYPE_STANDARD | UX_REQUEST_TARGET_DEVICE;
116 transfer_request -> ux_transfer_request_value = configuration_index | (UINT)(UX_CONFIGURATION_DESCRIPTOR_ITEM << 8);
117 transfer_request -> ux_transfer_request_index = 0;
118
119 /* Send request to HCD layer. */
120 status = _ux_host_stack_transfer_request(transfer_request);
121
122 /* Check for correct transfer and entire descriptor returned. */
123 if((status == UX_SUCCESS) && (transfer_request -> ux_transfer_request_actual_length == total_configuration_length))
124 {
125
126 /* The entire descriptor now contains the configuration descriptor,
127 the interface(s) descriptors, all alternate settings, endpoints
128 and descriptor specific to the class. The descriptor is parsed for all interfaces. */
129 status = _ux_host_stack_interfaces_scan(configuration, descriptor);
130 }
131 }
132
133 /* Free all used resources. */
134 _ux_utility_memory_free(descriptor);
135
136 /* Return completion status. */
137 return(status);
138 }
139
140
