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