/***************************************************************************
 * Copyright (c) 2024 Microsoft Corporation
 * Copyright (c) 2026-present Eclipse ThreadX contributors
 *
 * This program and the accompanying materials are made available under the
 * terms of the MIT License which is available at
 * https://opensource.org/licenses/MIT.
 *
 * SPDX-License-Identifier: MIT
 **************************************************************************/


/**************************************************************************/
/**************************************************************************/
/**                                                                       */
/** USBX Component                                                        */
/**                                                                       */
/**   ACM CDC Class                                                       */
/**                                                                       */
/**************************************************************************/
/**************************************************************************/


/* Include necessary system files.  */

#define UX_SOURCE_CODE

#include "ux_api.h"
#include "ux_host_class_cdc_acm.h"
#include "ux_host_stack.h"


/**************************************************************************/
/*                                                                        */
/*  FUNCTION                                               RELEASE        */
/*                                                                        */
/*    _ux_host_class_cdc_acm_reception_callback           PORTABLE C      */
/*                                                           6.1          */
/*  AUTHOR                                                                */
/*                                                                        */
/*    Chaoqiong Xiao, Microsoft Corporation                               */
/*                                                                        */
/*  DESCRIPTION                                                           */
/*                                                                        */
/*    This function is the callback from the USBX transfer functions,     */
/*    it is called when a full or partial transfer has been done for a    */
/*    bulk in transfer. It calls back the application.                    */
/*                                                                        */
/*  INPUT                                                                 */
/*                                                                        */
/*    transfer_request                      Pointer to transfer request   */
/*                                                                        */
/*  OUTPUT                                                                */
/*                                                                        */
/*    None                                                                */
/*                                                                        */
/*  CALLS                                                                 */
/*                                                                        */
/*    _ux_host_stack_transfer_request       Process transfer request      */
/*                                                                        */
/*  CALLED BY                                                             */
/*                                                                        */
/*    Application                                                         */
/*                                                                        */
/**************************************************************************/
VOID  _ux_host_class_cdc_acm_reception_callback (UX_TRANSFER *transfer_request)
{

UX_HOST_CLASS_CDC_ACM               *cdc_acm;
UX_HOST_CLASS_CDC_ACM_RECEPTION     *cdc_acm_reception;

    /* Get the class instance for this transfer request.  */
    cdc_acm =  (UX_HOST_CLASS_CDC_ACM *) transfer_request -> ux_transfer_request_class_instance;

    /* Get the pointer to the acm reception structure.  */
    cdc_acm_reception =  cdc_acm -> ux_host_class_cdc_acm_reception;

    /* Check the state of the transfer.  If there is an error, we do not proceed with this report.  */
    if (transfer_request -> ux_transfer_request_completion_code != UX_SUCCESS)
    {

        /* The reception is stopped.  */
        cdc_acm_reception -> ux_host_class_cdc_acm_reception_state =  UX_HOST_CLASS_CDC_ACM_RECEPTION_STATE_STOPPED;

        /* We do not proceed.  */
        return;

    }

    /* Move to the next reception buffer.  Check if we are at the end of the application buffer.  */
    if (cdc_acm_reception -> ux_host_class_cdc_acm_reception_data_head + cdc_acm_reception -> ux_host_class_cdc_acm_reception_block_size >=
        cdc_acm_reception -> ux_host_class_cdc_acm_reception_data_buffer + cdc_acm_reception -> ux_host_class_cdc_acm_reception_data_buffer_size)

            /* Program the head to be at the beginning of the application buffer.  */
            cdc_acm_reception -> ux_host_class_cdc_acm_reception_data_head =  cdc_acm_reception -> ux_host_class_cdc_acm_reception_data_buffer;

    else

            /* Program the head to be after the current buffer.  */
            cdc_acm_reception -> ux_host_class_cdc_acm_reception_data_head +=  cdc_acm_reception -> ux_host_class_cdc_acm_reception_block_size;

    /* OVERFLOW check: if the head reaches the tail buffer that contains reception data */
    if (cdc_acm_reception -> ux_host_class_cdc_acm_reception_data_tail ==  cdc_acm_reception -> ux_host_class_cdc_acm_reception_data_head)
    {

        /* Error trap. */
        _ux_system_error_handler(UX_SYSTEM_LEVEL_THREAD, UX_SYSTEM_CONTEXT_CLASS, UX_BUFFER_OVERFLOW);

        /* If trace is enabled, insert this event into the trace buffer.  */
        UX_TRACE_IN_LINE_INSERT(UX_TRACE_ERROR, UX_BUFFER_OVERFLOW, transfer_request, 0, 0, UX_TRACE_ERRORS, 0, 0)

        /* We have an overflow. We cannot continue.  Report to the application.  */
        cdc_acm_reception -> ux_host_class_cdc_acm_reception_callback(cdc_acm, UX_BUFFER_OVERFLOW, UX_NULL, 0);

        /* And stop the transfer in progress flag.  */
        cdc_acm_reception -> ux_host_class_cdc_acm_reception_state =  UX_HOST_CLASS_CDC_ACM_RECEPTION_STATE_STOPPED;

        return;
    }

    /* We need to report this transfer to the application.  */
    cdc_acm_reception -> ux_host_class_cdc_acm_reception_callback(cdc_acm,
                                                                    transfer_request -> ux_transfer_request_completion_code,
                                                                    transfer_request -> ux_transfer_request_data_pointer,
                                                                    transfer_request -> ux_transfer_request_actual_length);

    /* Set data pointer to the next reception buffer.  */
    transfer_request -> ux_transfer_request_data_pointer = cdc_acm_reception -> ux_host_class_cdc_acm_reception_data_head;

    /* Arm another transfer.  */
    _ux_host_stack_transfer_request(transfer_request);

    /* There is no status to be reported back to the stack.  */
    return;
}

