// SPDX-License-Identifier: GPL-2.0+
/* Copyright (c) 2022 Amarula Solutions, Dario Binacchi <dario.binacchi@amarulasolutions.com>
 * Copyright (c) 2022 Pengutronix, Marc Kleine-Budde <kernel@pengutronix.de>
 *
 */

#include <linux/can/dev.h>
#include <linux/ethtool.h>
#include <linux/kernel.h>
#include <linux/netdevice.h>
#include <linux/platform_device.h>

#include "flexcan.h"

static const char flexcan_priv_flags_strings[][ETH_GSTRING_LEN] = {
#define FLEXCAN_PRIV_FLAGS_RX_RTR BIT(0)
        "rx-rtr",
};

static void
flexcan_get_ringparam(struct net_device *ndev, struct ethtool_ringparam *ring,
                      struct kernel_ethtool_ringparam *kernel_ring,
                      struct netlink_ext_ack *ext_ack)
{
        const struct flexcan_priv *priv = netdev_priv(ndev);

        ring->rx_max_pending = priv->mb_count;
        ring->tx_max_pending = priv->mb_count;

        if (priv->devtype_data.quirks & FLEXCAN_QUIRK_USE_RX_MAILBOX)
                ring->rx_pending = priv->offload.mb_last -
                        priv->offload.mb_first + 1;
        else
                ring->rx_pending = 6;   /* RX-FIFO depth is fixed */

        /* the drive currently supports only on TX buffer */
        ring->tx_pending = 1;
}

static void
flexcan_get_strings(struct net_device *ndev, u32 stringset, u8 *data)
{
        switch (stringset) {
        case ETH_SS_PRIV_FLAGS:
                memcpy(data, flexcan_priv_flags_strings,
                       sizeof(flexcan_priv_flags_strings));
        }
}

static u32 flexcan_get_priv_flags(struct net_device *ndev)
{
        const struct flexcan_priv *priv = netdev_priv(ndev);
        u32 priv_flags = 0;

        if (flexcan_active_rx_rtr(priv))
                priv_flags |= FLEXCAN_PRIV_FLAGS_RX_RTR;

        return priv_flags;
}

static int flexcan_set_priv_flags(struct net_device *ndev, u32 priv_flags)
{
        struct flexcan_priv *priv = netdev_priv(ndev);
        u32 quirks = priv->devtype_data.quirks;

        if (priv_flags & FLEXCAN_PRIV_FLAGS_RX_RTR) {
                if (flexcan_supports_rx_mailbox_rtr(priv))
                        quirks |= FLEXCAN_QUIRK_USE_RX_MAILBOX;
                else if (flexcan_supports_rx_fifo(priv))
                        quirks &= ~FLEXCAN_QUIRK_USE_RX_MAILBOX;
                else
                        quirks |= FLEXCAN_QUIRK_USE_RX_MAILBOX;
        } else {
                if (flexcan_supports_rx_mailbox(priv))
                        quirks |= FLEXCAN_QUIRK_USE_RX_MAILBOX;
                else
                        quirks &= ~FLEXCAN_QUIRK_USE_RX_MAILBOX;
        }

        if (quirks != priv->devtype_data.quirks && netif_running(ndev))
                return -EBUSY;

        priv->devtype_data.quirks = quirks;

        if (!(priv_flags & FLEXCAN_PRIV_FLAGS_RX_RTR) &&
            !flexcan_active_rx_rtr(priv))
                netdev_info(ndev,
                            "Activating RX mailbox mode, cannot receive RTR frames.\n");

        return 0;
}

static int flexcan_get_sset_count(struct net_device *netdev, int sset)
{
        switch (sset) {
        case ETH_SS_PRIV_FLAGS:
                return ARRAY_SIZE(flexcan_priv_flags_strings);
        default:
                return -EOPNOTSUPP;
        }
}

const struct ethtool_ops flexcan_ethtool_ops = {
        .get_ringparam = flexcan_get_ringparam,
        .get_strings = flexcan_get_strings,
        .get_priv_flags = flexcan_get_priv_flags,
        .set_priv_flags = flexcan_set_priv_flags,
        .get_sset_count = flexcan_get_sset_count,
        .get_ts_info = ethtool_op_get_ts_info,
};