// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * ASIX AX88172A based USB 2.0 Ethernet Devices
 * Copyright (C) 2012 OMICRON electronics GmbH
 *
 * Supports external PHYs via phylib. Based on the driver for the
 * AX88772. Original copyrights follow:
 *
 * Copyright (C) 2003-2006 David Hollis <dhollis@davehollis.com>
 * Copyright (C) 2005 Phil Chang <pchang23@sbcglobal.net>
 * Copyright (C) 2006 James Painter <jamie.painter@iname.com>
 * Copyright (c) 2002-2003 TiVo Inc.
 */

#include "asix.h"
#include <linux/phy.h>

struct ax88172a_private {
        struct mii_bus *mdio;
        struct phy_device *phydev;
        char phy_name[PHY_ID_SIZE];
        u8 phy_addr;
        u16 oldmode;
        int use_embdphy;
        struct asix_rx_fixup_info rx_fixup_info;
};

/* set MAC link settings according to information from phylib */
static void ax88172a_adjust_link(struct net_device *netdev)
{
        struct phy_device *phydev = netdev->phydev;
        struct usbnet *dev = netdev_priv(netdev);
        struct ax88172a_private *priv = dev->driver_priv;
        u16 mode = 0;

        if (phydev->link) {
                mode = AX88772_MEDIUM_DEFAULT;

                if (phydev->duplex == DUPLEX_HALF)
                        mode &= ~AX_MEDIUM_FD;

                if (phydev->speed != SPEED_100)
                        mode &= ~AX_MEDIUM_PS;
        }

        if (mode != priv->oldmode) {
                asix_write_medium_mode(dev, mode, 0);
                priv->oldmode = mode;
                netdev_dbg(netdev, "speed %u duplex %d, setting mode to 0x%04x\n",
                           phydev->speed, phydev->duplex, mode);
                phy_print_status(phydev);
        }
}

static void ax88172a_status(struct usbnet *dev, struct urb *urb)
{
        /* link changes are detected by polling the phy */
}

/* use phylib infrastructure */
static int ax88172a_init_mdio(struct usbnet *dev)
{
        struct ax88172a_private *priv = dev->driver_priv;
        int ret;

        priv->mdio = mdiobus_alloc();
        if (!priv->mdio) {
                netdev_err(dev->net, "Could not allocate MDIO bus\n");
                return -ENOMEM;
        }

        priv->mdio->priv = (void *)dev;
        priv->mdio->read = &asix_mdio_bus_read;
        priv->mdio->write = &asix_mdio_bus_write;
        priv->mdio->name = "Asix MDIO Bus";
        /* mii bus name is usb-<usb bus number>-<usb device number> */
        snprintf(priv->mdio->id, MII_BUS_ID_SIZE, "usb-%03d:%03d",
                 dev->udev->bus->busnum, dev->udev->devnum);

        ret = mdiobus_register(priv->mdio);
        if (ret) {
                netdev_err(dev->net, "Could not register MDIO bus\n");
                goto mfree;
        }

        netdev_info(dev->net, "registered mdio bus %s\n", priv->mdio->id);
        return 0;

mfree:
        mdiobus_free(priv->mdio);
        return ret;
}

static void ax88172a_remove_mdio(struct usbnet *dev)
{
        struct ax88172a_private *priv = dev->driver_priv;

        netdev_info(dev->net, "deregistering mdio bus %s\n", priv->mdio->id);
        mdiobus_unregister(priv->mdio);
        mdiobus_free(priv->mdio);
}

static const struct net_device_ops ax88172a_netdev_ops = {
        .ndo_open               = usbnet_open,
        .ndo_stop               = usbnet_stop,
        .ndo_start_xmit         = usbnet_start_xmit,
        .ndo_tx_timeout         = usbnet_tx_timeout,
        .ndo_change_mtu         = usbnet_change_mtu,
        .ndo_get_stats64        = dev_get_tstats64,
        .ndo_set_mac_address    = asix_set_mac_address,
        .ndo_validate_addr      = eth_validate_addr,
        .ndo_eth_ioctl          = phy_do_ioctl_running,
        .ndo_set_rx_mode        = asix_set_multicast,
};

static const struct ethtool_ops ax88172a_ethtool_ops = {
        .get_drvinfo            = usbnet_get_drvinfo,
        .get_link               = usbnet_get_link,
        .get_msglevel           = usbnet_get_msglevel,
        .set_msglevel           = usbnet_set_msglevel,
        .get_wol                = asix_get_wol,
        .set_wol                = asix_set_wol,
        .get_eeprom_len         = asix_get_eeprom_len,
        .get_eeprom             = asix_get_eeprom,
        .set_eeprom             = asix_set_eeprom,
        .nway_reset             = phy_ethtool_nway_reset,
        .get_link_ksettings     = phy_ethtool_get_link_ksettings,
        .set_link_ksettings     = phy_ethtool_set_link_ksettings,
};

static int ax88172a_reset_phy(struct usbnet *dev, int embd_phy)
{
        int ret;

        ret = asix_sw_reset(dev, AX_SWRESET_IPPD, 0);
        if (ret < 0)
                goto err;

        msleep(150);
        ret = asix_sw_reset(dev, AX_SWRESET_CLEAR, 0);
        if (ret < 0)
                goto err;

        msleep(150);

        ret = asix_sw_reset(dev, embd_phy ? AX_SWRESET_IPRL : AX_SWRESET_IPPD,
                            0);
        if (ret < 0)
                goto err;

        return 0;

err:
        return ret;
}


static int ax88172a_bind(struct usbnet *dev, struct usb_interface *intf)
{
        int ret;
        u8 buf[ETH_ALEN];
        struct ax88172a_private *priv;

        ret = usbnet_get_endpoints(dev, intf);
        if (ret)
                return ret;

        priv = kzalloc_obj(*priv);
        if (!priv)
                return -ENOMEM;

        dev->driver_priv = priv;

        /* Get the MAC address */
        ret = asix_read_cmd(dev, AX_CMD_READ_NODE_ID, 0, 0, ETH_ALEN, buf, 0);
        if (ret < ETH_ALEN) {
                netdev_err(dev->net, "Failed to read MAC address: %d\n", ret);
                ret = -EIO;
                goto free;
        }
        eth_hw_addr_set(dev->net, buf);

        dev->net->netdev_ops = &ax88172a_netdev_ops;
        dev->net->ethtool_ops = &ax88172a_ethtool_ops;

        /* are we using the internal or the external phy? */
        ret = asix_read_cmd(dev, AX_CMD_SW_PHY_STATUS, 0, 0, 1, buf, 0);
        if (ret < 0) {
                netdev_err(dev->net, "Failed to read software interface selection register: %d\n",
                           ret);
                goto free;
        }

        netdev_dbg(dev->net, "AX_CMD_SW_PHY_STATUS = 0x%02x\n", buf[0]);
        switch (buf[0] & AX_PHY_SELECT_MASK) {
        case AX_PHY_SELECT_INTERNAL:
                netdev_dbg(dev->net, "use internal phy\n");
                priv->use_embdphy = 1;
                break;
        case AX_PHY_SELECT_EXTERNAL:
                netdev_dbg(dev->net, "use external phy\n");
                priv->use_embdphy = 0;
                break;
        default:
                netdev_err(dev->net, "Interface mode not supported by driver\n");
                ret = -ENOTSUPP;
                goto free;
        }

        ret = asix_read_phy_addr(dev, priv->use_embdphy);
        if (ret < 0)
                goto free;

        priv->phy_addr = ret;

        ax88172a_reset_phy(dev, priv->use_embdphy);

        /* Asix framing packs multiple eth frames into a 2K usb bulk transfer */
        if (dev->driver_info->flags & FLAG_FRAMING_AX) {
                /* hard_mtu  is still the default - the device does not support
                   jumbo eth frames */
                dev->rx_urb_size = 2048;
        }

        /* init MDIO bus */
        ret = ax88172a_init_mdio(dev);
        if (ret)
                goto free;

        return 0;

free:
        kfree(priv);
        return ret;
}

static int ax88172a_stop(struct usbnet *dev)
{
        struct ax88172a_private *priv = dev->driver_priv;

        netdev_dbg(dev->net, "Stopping interface\n");

        if (priv->phydev) {
                netdev_info(dev->net, "Disconnecting from phy %s\n",
                            priv->phy_name);
                phy_stop(priv->phydev);
                phy_disconnect(priv->phydev);
        }

        return 0;
}

static void ax88172a_unbind(struct usbnet *dev, struct usb_interface *intf)
{
        struct ax88172a_private *priv = dev->driver_priv;

        ax88172a_remove_mdio(dev);
        kfree(priv);
}

static int ax88172a_reset(struct usbnet *dev)
{
        struct asix_data *data = (struct asix_data *)&dev->data;
        struct ax88172a_private *priv = dev->driver_priv;
        int ret;
        u16 rx_ctl;

        ax88172a_reset_phy(dev, priv->use_embdphy);

        msleep(150);
        rx_ctl = asix_read_rx_ctl(dev, 0);
        netdev_dbg(dev->net, "RX_CTL is 0x%04x after software reset\n", rx_ctl);
        ret = asix_write_rx_ctl(dev, 0x0000, 0);
        if (ret < 0)
                goto out;

        rx_ctl = asix_read_rx_ctl(dev, 0);
        netdev_dbg(dev->net, "RX_CTL is 0x%04x setting to 0x0000\n", rx_ctl);

        msleep(150);

        ret = asix_write_cmd(dev, AX_CMD_WRITE_IPG0,
                             AX88772_IPG0_DEFAULT | AX88772_IPG1_DEFAULT,
                             AX88772_IPG2_DEFAULT, 0, NULL, 0);
        if (ret < 0) {
                netdev_err(dev->net, "Write IPG,IPG1,IPG2 failed: %d\n", ret);
                goto out;
        }

        /* Rewrite MAC address */
        memcpy(data->mac_addr, dev->net->dev_addr, ETH_ALEN);
        ret = asix_write_cmd(dev, AX_CMD_WRITE_NODE_ID, 0, 0, ETH_ALEN,
                             data->mac_addr, 0);
        if (ret < 0)
                goto out;

        /* Set RX_CTL to default values with 2k buffer, and enable cactus */
        ret = asix_write_rx_ctl(dev, AX_DEFAULT_RX_CTL, 0);
        if (ret < 0)
                goto out;

        rx_ctl = asix_read_rx_ctl(dev, 0);
        netdev_dbg(dev->net, "RX_CTL is 0x%04x after all initializations\n",
                   rx_ctl);

        rx_ctl = asix_read_medium_status(dev, 0);
        netdev_dbg(dev->net, "Medium Status is 0x%04x after all initializations\n",
                   rx_ctl);

        /* Connect to PHY */
        snprintf(priv->phy_name, sizeof(priv->phy_name), PHY_ID_FMT,
                 priv->mdio->id, priv->phy_addr);

        priv->phydev = phy_connect(dev->net, priv->phy_name,
                                   &ax88172a_adjust_link,
                                   PHY_INTERFACE_MODE_MII);
        if (IS_ERR(priv->phydev)) {
                netdev_err(dev->net, "Could not connect to PHY device %s\n",
                           priv->phy_name);
                ret = PTR_ERR(priv->phydev);
                goto out;
        }

        netdev_info(dev->net, "Connected to phy %s\n", priv->phy_name);

        /* During power-up, the AX88172A set the power down (BMCR_PDOWN)
         * bit of the PHY. Bring the PHY up again.
         */
        genphy_resume(priv->phydev);
        phy_start(priv->phydev);

        return 0;

out:
        return ret;

}

static int ax88172a_rx_fixup(struct usbnet *dev, struct sk_buff *skb)
{
        struct ax88172a_private *dp = dev->driver_priv;
        struct asix_rx_fixup_info *rx = &dp->rx_fixup_info;

        return asix_rx_fixup_internal(dev, skb, rx);
}

const struct driver_info ax88172a_info = {
        .description = "ASIX AX88172A USB 2.0 Ethernet",
        .bind = ax88172a_bind,
        .reset = ax88172a_reset,
        .stop = ax88172a_stop,
        .unbind = ax88172a_unbind,
        .status = ax88172a_status,
        .flags = FLAG_ETHER | FLAG_FRAMING_AX | FLAG_LINK_INTR |
                 FLAG_MULTI_PACKET,
        .rx_fixup = ax88172a_rx_fixup,
        .tx_fixup = asix_tx_fixup,
};