/*!
    \file  usbh_hcs.c
    \brief this file implements functions for opening and closing host channels
*/

/*
    Copyright (C) 2017 GigaDevice

    2017-02-10, V1.0.0, firmware for GD32F30x
*/

#include "usbh_hcs.h"

static uint16_t usbh_freechannel_get (usb_core_handle_struct *pudev);

/*!
    \brief      open a channel
    \param[in]  pudev: pointer to usb device
    \param[in]  channel_num: host channel number which is in (0..7)
    \param[in]  dev_addr: USB device address allocated to attached device
    \param[in]  dev_speed: USB device speed (Full speed/Low speed)
    \param[in]  ep_type: endpoint type (bulk/int/ctl)
    \param[in]  ep_mps: max packet size
    \param[out] none
    \retval     operation status
*/
uint8_t usbh_channel_open (usb_core_handle_struct *pudev, 
                           uint8_t  channel_num,
                           uint8_t  dev_addr,
                           uint8_t  dev_speed,
                           uint8_t  ep_type,
                           uint16_t ep_mps)
{
    usb_hostchannel_struct *puhc = &pudev->host.host_channel[channel_num];
    uint16_t channel_info = puhc->info;

    puhc->endp_id   = (uint8_t)channel_info & 0x7FU;
    puhc->endp_in   = (uint8_t)(channel_info & 0x80U) >> 7;
    puhc->endp_type = ep_type;
    puhc->endp_mps  = ep_mps;
    puhc->dev_addr  = dev_addr;
    puhc->dev_speed = dev_speed;

    puhc->data_tg_in  = 0U;
    puhc->data_tg_out = 0U;

    usb_hostchannel_init(pudev, channel_num);

    return (uint8_t)HC_OK;
}

/*!
    \brief      modify a channel
    \param[in]  pudev: pointer to usb device
    \param[in]  channel_num: host channel number which is in (0..7)
    \param[in]  dev_addr: USB Device address allocated to attached device
    \param[in]  dev_speed: USB device speed (Full speed/Low speed)
    \param[in]  ep_type: endpoint type (bulk/int/ctl)
    \param[in]  ep_mps: max packet size
    \param[out] none
    \retval     operation status
*/
uint8_t usbh_channel_modify (usb_core_handle_struct *pudev,
                             uint8_t  channel_num,
                             uint8_t  dev_addr,
                             uint8_t  dev_speed,
                             uint8_t  ep_type,
                             uint16_t ep_mps)
{
    usb_hostchannel_struct *puhc = &pudev->host.host_channel[channel_num];

    if (0U != dev_addr) {
        puhc->dev_addr = dev_addr;
    }

    if ((puhc->endp_mps != ep_mps) && (0U != ep_mps)) {
        puhc->endp_mps = ep_mps; 
    }

    if ((puhc->dev_speed != dev_speed) && (0U != dev_speed)) {
        puhc->dev_speed = dev_speed;
    }

    usb_hostchannel_init(pudev, channel_num);

    return (uint8_t)HC_OK;
}

/*!
    \brief      allocate a new channel for the pipe
    \param[in]  pudev: pointer to usb device
    \param[in]  ep_addr: endpoint for which the channel to be allocated
    \param[out] none
    \retval     host channel number
*/
uint8_t usbh_channel_alloc (usb_core_handle_struct *pudev, uint8_t ep_addr)
{
    uint16_t hc_num = usbh_freechannel_get(pudev);

    if ((uint16_t)HC_ERROR != hc_num) {
        pudev->host.host_channel[hc_num].info = HC_USED | ep_addr;
    }

    return (uint8_t)hc_num;
}

/*!
    \brief      free the usb host channel
    \param[in]  pudev: pointer to usb device
    \param[in]  index: channel number to be freed  which is in (0..7)
    \param[out] none
    \retval     host operation status
*/
uint8_t usbh_channel_free (usb_core_handle_struct *pudev, uint8_t index)
{
    if (index < HC_MAX) {
        pudev->host.host_channel[index].info &= HC_USED_MASK;
    }

    return USBH_OK;
}

/*!
    \brief      free all usb host channel
    \param[in]  pudev: pointer to usb device
    \param[out] none
    \retval     host operation status
*/
uint8_t usbh_allchannel_dealloc (usb_core_handle_struct *pudev)
{
    uint8_t index;

    for (index = 2U; index < HC_MAX; index ++) {
        pudev->host.host_channel[index].info = 0U;
    }

    return USBH_OK;
}

/*!
    \brief      get a free channel number for allocation to a device endpoint
    \param[in]  pudev: pointer to usb device
    \param[out] none
    \retval     free channel number
*/
static uint16_t usbh_freechannel_get (usb_core_handle_struct *pudev)
{
    uint8_t index = 0U;

    for (index = 0U; index < HC_MAX; index++) {
        if (0U == (pudev->host.host_channel[index].info & HC_USED)) {
            return (uint16_t)index;
        }
    }

    return HC_ERROR;
}