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/**************************************************************************/
/* */
/* 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 */
/** */
/** Host Stack */
/** */
/**************************************************************************/
/**************************************************************************/
/* Include necessary system files. */
#define UX_SOURCE_CODE
#include "ux_api.h"
#include "ux_host_stack.h"
/**************************************************************************/
/* */
/* FUNCTION RELEASE */
/* */
/* _ux_host_stack_device_descriptor_read PORTABLE C */
/* 6.1.10 */
/* AUTHOR */
/* */
/* Chaoqiong Xiao, Microsoft Corporation */
/* */
/* DESCRIPTION */
/* */
/* This function reads the device descriptor. */
/* */
/* INPUT */
/* */
/* device Pointer to device */
/* */
/* OUTPUT */
/* */
/* Completion Status */
/* */
/* CALLS */
/* */
/* _ux_host_stack_transfer_request Process transfer request */
/* _ux_utility_descriptor_parse Parse descriptor */
/* _ux_utility_memory_allocate Allocate memory block */
/* _ux_utility_memory_free Free memory block */
/* */
/* CALLED BY */
/* */
/* USBX Components */
/* */
/* 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 */
/* 10-15-2021 Chaoqiong Xiao Modified comment(s), */
/* added bMaxPacketSize0 check,*/
/* resulting in version 6.1.9 */
/* 01-31-2022 Chaoqiong Xiao Modified comment(s), */
/* added standalone support, */
/* added class code checking, */
/* resulting in version 6.1.10 */
/* */
/**************************************************************************/
UINT _ux_host_stack_device_descriptor_read(UX_DEVICE *device)
{
UX_TRANSFER *transfer_request;
UINT status;
UCHAR * descriptor;
UX_ENDPOINT *control_endpoint;
/* If trace is enabled, insert this event into the trace buffer. */
UX_TRACE_IN_LINE_INSERT(UX_TRACE_HOST_STACK_DEVICE_DESCRIPTOR_READ, device, 0, 0, 0, UX_TRACE_HOST_STACK_EVENTS, 0, 0)
/* Retrieve the pointer to the control endpoint. */
control_endpoint = &device -> ux_device_control_endpoint;
transfer_request = &control_endpoint -> ux_endpoint_transfer_request;
/* Need to allocate memory for the descriptor. */
descriptor = _ux_utility_memory_allocate(UX_SAFE_ALIGN, UX_CACHE_SAFE_MEMORY, UX_DEVICE_DESCRIPTOR_LENGTH);
if (descriptor == UX_NULL)
return(UX_MEMORY_INSUFFICIENT);
/* Create a transfer_request for the GET_DESCRIPTOR request. The first transfer_request asks
for the first 8 bytes only. This way we will know the real MaxPacketSize
value for the control endpoint. */
transfer_request -> ux_transfer_request_data_pointer = descriptor;
transfer_request -> ux_transfer_request_requested_length = 8;
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_DEVICE;
transfer_request -> ux_transfer_request_value = UX_DEVICE_DESCRIPTOR_ITEM << 8;
transfer_request -> ux_transfer_request_index = 0;
#if defined(UX_HOST_STANDALONE)
device -> ux_device_enum_trans = transfer_request;
status = UX_SUCCESS;
return(status);
#else
/* 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 == 8))
{
/* Parse the device descriptor and create the local descriptor. */
_ux_utility_descriptor_parse(descriptor, _ux_system_device_descriptor_structure, UX_DEVICE_DESCRIPTOR_ENTRIES,
(UCHAR *) &device -> ux_device_descriptor);
}
else
{
/* Free all used resources. */
_ux_utility_memory_free(descriptor);
/* Return completion status. */
return(status);
}
/* Validate the bMaxPacketSize0. */
if (device -> ux_device_descriptor.bMaxPacketSize0 != 8 &&
device -> ux_device_descriptor.bMaxPacketSize0 != 16 &&
device -> ux_device_descriptor.bMaxPacketSize0 != 32 &&
device -> ux_device_descriptor.bMaxPacketSize0 != 64)
{
_ux_utility_memory_free(descriptor);
return(UX_DESCRIPTOR_CORRUPTED);
}
#if defined(UX_HOST_DEVICE_CLASS_CODE_VALIDATION_ENABLE)
/* Validate the USB-IF bDeviceClass class code. */
switch(device -> ux_device_descriptor.bDeviceClass)
{
case 0x00: /* Fall through. */
case 0x02: /* Fall through. */
case 0x09: /* Fall through. */
case 0x11: /* Fall through. */
case 0xDC: /* Fall through. */
case 0xEF: /* Fall through. */
case 0xFF:
break;
default:
/* Invalid device class code. */
_ux_utility_memory_free(descriptor);
return(UX_DESCRIPTOR_CORRUPTED);
}
#endif
/* Update the max packet size value for the endpoint. */
control_endpoint -> ux_endpoint_descriptor.wMaxPacketSize = device -> ux_device_descriptor.bMaxPacketSize0;
/* Create a transfer_request for the GET_DESCRIPTOR request. This time, we have the complete length */
transfer_request -> ux_transfer_request_data_pointer = descriptor;
transfer_request -> ux_transfer_request_requested_length = UX_DEVICE_DESCRIPTOR_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_DEVICE;
transfer_request -> ux_transfer_request_value = UX_DEVICE_DESCRIPTOR_ITEM << 8;
transfer_request -> ux_transfer_request_index = 0;
transfer_request -> ux_transfer_request_packet_length = device -> ux_device_descriptor.bMaxPacketSize0;
/* 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 == UX_DEVICE_DESCRIPTOR_LENGTH))
{
/* Parse the device descriptor and create the local descriptor. */
_ux_utility_descriptor_parse(descriptor, _ux_system_device_descriptor_structure, UX_DEVICE_DESCRIPTOR_ENTRIES,
(UCHAR *) &device -> ux_device_descriptor);
}
else
{
/* Error trap. */
_ux_system_error_handler(UX_SYSTEM_LEVEL_THREAD, UX_SYSTEM_CONTEXT_ENUMERATOR, 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 device descriptor does not contain the right amount of data. Maybe corruption. */
status = UX_DESCRIPTOR_CORRUPTED;
}
/* Free all used resources. */
_ux_utility_memory_free(descriptor);
/* Return completion status. */
return(status);
#endif
}