asix: Add a new driver for the AX88172A

The Asix AX88172A is a USB 2.0 Ethernet interface that supports both an
internal PHY as well as an external PHY (connected via MII).

This patch adds a driver for the AX88172A and provides support for
both modes and the phylib.

Signed-off-by: Christian Riesch <christian.riesch@omicron.at>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 415 insertions, 0 deletions

diff --git a/drivers/net/usb/ax88172a.c b/drivers/net/usb/ax88172a.c
new file mode 100644
index 000000000000..534a144bd9e7
--- /dev/null
+++ b/drivers/net/usb/ax88172a.c
@@ -0,0 +1,415 @@
+/*
+ * 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.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#include "asix.h"
+#include <linux/phy.h>
+
+struct ax88172a_private {
+        struct mii_bus *mdio;
+        struct phy_device *phydev;
+        char phy_name[20];
+        u16 phy_addr;
+        u16 oldmode;
+        int use_embdphy;
+};
+
+/* MDIO read and write wrappers for phylib */
+static int asix_mdio_bus_read(struct mii_bus *bus, int phy_id, int regnum)
+{
+        return asix_mdio_read(((struct usbnet *)bus->priv)->net, phy_id,
+                              regnum);
+}
+
+static int asix_mdio_bus_write(struct mii_bus *bus, int phy_id, int regnum,
+                               u16 val)
+{
+        asix_mdio_write(((struct usbnet *)bus->priv)->net, phy_id, regnum, val);
+        return 0;
+}
+
+static int ax88172a_ioctl(struct net_device *net, struct ifreq *rq, int cmd)
+{
+        if (!netif_running(net))
+                return -EINVAL;
+
+        if (!net->phydev)
+                return -ENODEV;
+
+        return phy_mii_ioctl(net->phydev, rq, cmd);
+}
+
+/* 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);
+                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, i;
+
+        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);
+
+        priv->mdio->irq = kzalloc(sizeof(int) * PHY_MAX_ADDR, GFP_KERNEL);
+        if (!priv->mdio->irq) {
+                netdev_err(dev->net, "Could not allocate mdio->irq\n");
+                ret = -ENOMEM;
+                goto mfree;
+        }
+        for (i = 0; i < PHY_MAX_ADDR; i++)
+                priv->mdio->irq[i] = PHY_POLL;
+
+        ret = mdiobus_register(priv->mdio);
+        if (ret) {
+                netdev_err(dev->net, "Could not register MDIO bus\n");
+                goto ifree;
+        }
+
+        netdev_info(dev->net, "registered mdio bus %s\n", priv->mdio->id);
+        return 0;
+
+ifree:
+        kfree(priv->mdio->irq);
+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);
+        kfree(priv->mdio->irq);
+        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_set_mac_address    = asix_set_mac_address,
+        .ndo_validate_addr      = eth_validate_addr,
+        .ndo_do_ioctl           = ax88172a_ioctl,
+        .ndo_set_rx_mode        = asix_set_multicast,
+};
+
+int ax88172a_get_settings(struct net_device *net, struct ethtool_cmd *cmd)
+{
+        if (!net->phydev)
+                return -ENODEV;
+
+        return phy_ethtool_gset(net->phydev, cmd);
+}
+
+int ax88172a_set_settings(struct net_device *net, struct ethtool_cmd *cmd)
+{
+        if (!net->phydev)
+                return -ENODEV;
+
+        return phy_ethtool_sset(net->phydev, cmd);
+}
+
+int ax88172a_nway_reset(struct net_device *net)
+{
+        if (!net->phydev)
+                return -ENODEV;
+
+        return phy_start_aneg(net->phydev);
+}
+
+static const struct ethtool_ops ax88172a_ethtool_ops = {
+        .get_drvinfo            = asix_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,
+        .get_settings           = ax88172a_get_settings,
+        .set_settings           = ax88172a_set_settings,
+        .nway_reset             = ax88172a_nway_reset,
+};
+
+static int ax88172a_reset_phy(struct usbnet *dev, int embd_phy)
+{
+        int ret;
+
+        ret = asix_sw_reset(dev, AX_SWRESET_IPPD);
+        if (ret < 0)
+                goto err;
+
+        msleep(150);
+        ret = asix_sw_reset(dev, AX_SWRESET_CLEAR);
+        if (ret < 0)
+                goto err;
+
+        msleep(150);
+
+        ret = asix_sw_reset(dev, embd_phy ? AX_SWRESET_IPRL : AX_SWRESET_IPPD);
+        if (ret < 0)
+                goto err;
+
+        return 0;
+
+err:
+        return ret;
+}
+
+
+static int ax88172a_bind(struct usbnet *dev, struct usb_interface *intf)
+{
+        int ret;
+        struct asix_data *data = (struct asix_data *)&dev->data;
+        u8 buf[ETH_ALEN];
+        struct ax88172a_private *priv;
+
+        data->eeprom_len = AX88772_EEPROM_LEN;
+
+        usbnet_get_endpoints(dev, intf);
+
+        priv = kzalloc(sizeof(*priv), GFP_KERNEL);
+        if (!priv) {
+                netdev_err(dev->net, "Could not allocate memory for private data\n");
+                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);
+        if (ret < 0) {
+                netdev_err(dev->net, "Failed to read MAC address: %d\n", ret);
+                goto free;
+        }
+        memcpy(dev->net->dev_addr, buf, ETH_ALEN);
+
+        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);
+        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");
+                goto free;
+        }
+
+        priv->phy_addr = asix_read_phy_addr(dev, priv->use_embdphy);
+        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);
+        netdev_dbg(dev->net, "RX_CTL is 0x%04x after software reset\n", rx_ctl);
+        ret = asix_write_rx_ctl(dev, 0x0000);
+        if (ret < 0)
+                goto out;
+
+        rx_ctl = asix_read_rx_ctl(dev);
+        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);
+        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);
+        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);
+        if (ret < 0)
+                goto out;
+
+        rx_ctl = asix_read_rx_ctl(dev);
+        netdev_dbg(dev->net, "RX_CTL is 0x%04x after all initializations\n",
+                   rx_ctl);
+
+        rx_ctl = asix_read_medium_status(dev);
+        netdev_dbg(dev->net, "Medium Status is 0x%04x after all initializations\n",
+                   rx_ctl);
+
+        /* Connect to PHY */
+        snprintf(priv->phy_name, 20, PHY_ID_FMT,
+                 priv->mdio->id, priv->phy_addr);
+
+        priv->phydev = phy_connect(dev->net, priv->phy_name,
+                                   &ax88172a_adjust_link,
+                                   0, 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;
+
+}
+
+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 = asix_rx_fixup,
+        .tx_fixup = asix_tx_fixup,
+};