/***************************************************************************
 * 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                                                        */
/**                                                                       */
/**   Host Stack                                                          */
/**                                                                       */
/**************************************************************************/
/**************************************************************************/


/* Include necessary system files.  */

#define UX_SOURCE_CODE

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


/**************************************************************************/
/*                                                                        */
/*  FUNCTION                                               RELEASE        */
/*                                                                        */
/*    _ux_host_stack_role_swap                            PORTABLE C      */
/*                                                           6.1.10       */
/*  AUTHOR                                                                */
/*                                                                        */
/*    Chaoqiong Xiao, Microsoft Corporation                               */
/*                                                                        */
/*  DESCRIPTION                                                           */
/*                                                                        */
/*    This function is called when the host or the device demand a role   */
/*    swap. This function may be called by an application or by the HNP   */
/*    thread.                                                             */
/*                                                                        */
/*  INPUT                                                                 */
/*                                                                        */
/*    hcd                                       Pointer to HCD            */
/*    device                                    Device pointer            */
/*                                                                        */
/*  OUTPUT                                                                */
/*                                                                        */
/*    Status                                                              */
/*                                                                        */
/*  CALLS                                                                 */
/*                                                                        */
/*    _ux_utility_semaphore_get                 Get semaphore             */
/*    _ux_host_stack_transfer_request           Transfer request          */
/*                                                                        */
/*  CALLED BY                                                             */
/*                                                                        */
/*    Application of HNP thread.                                          */
/*                                                                        */
/**************************************************************************/
UINT  _ux_host_stack_role_swap(UX_DEVICE *device)
{

#if !defined(UX_OTG_SUPPORT)

    UX_PARAMETER_NOT_USED(device);
    return(UX_FUNCTION_NOT_SUPPORTED);
#else

UX_ENDPOINT     *control_endpoint;
UX_TRANSFER     *transfer_request;
UINT            status;

    /* Retrieve the control endpoint and the transfer request associated with it.  */
    control_endpoint =  &device -> ux_device_control_endpoint;
    transfer_request =  &control_endpoint -> ux_endpoint_transfer_request;

    /* Protect the control endpoint semaphore here.  It will be unprotected in the
       transfer request function.  */
    status =  _ux_host_semaphore_get(&device -> ux_device_protection_semaphore, UX_WAIT_FOREVER);

    /* Perform a SET_FEATURE on this device to inform the it we are ready to change role.  */
    transfer_request -> ux_transfer_request_requested_length =  0;
    transfer_request -> ux_transfer_request_function =          UX_SET_FEATURE;
    transfer_request -> ux_transfer_request_type =              UX_REQUEST_OUT | UX_REQUEST_TYPE_STANDARD | UX_REQUEST_TARGET_DEVICE;
    transfer_request -> ux_transfer_request_value =             UX_OTG_FEATURE_B_HNP_ENABLE;
    transfer_request -> ux_transfer_request_index =             0;

    /* Send request to HCD layer.  */
    status =  _ux_host_stack_transfer_request(transfer_request);

    /* If the status fails, simply ignore the command but do not proceed.  */
    if (status != UX_SUCCESS)

        /* We have an error. Do not proceed. */
        return(status);

    /* Keep track of the event for HNP synchronization.  */
    _ux_system_otg -> ux_system_otg_change_mode_event = UX_OTG_HOST_TO_SLAVE;

    /* Call the OTG function that will perform the swap.  */
    _ux_system_otg -> ux_system_otg_function(UX_OTG_HOST_TO_SLAVE);

    /* Reset the event.  */
    _ux_system_otg -> ux_system_otg_change_mode_event = 0;

    return(UX_SUCCESS);
#endif
}