[PATCH v2 net-next 11/21] net: usb: aqc111: Add support for changing MTU

[Igor Russkikh]

From: Dmitry Bezrukov <dmitry.bezru...@aquantia.com>

Signed-off-by: Dmitry Bezrukov <dmitry.bezru...@aquantia.com>
Signed-off-by: Igor Russkikh <igor.russk...@aquantia.com>
---
 drivers/net/usb/aqc111.c | 60 +++++++++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 59 insertions(+), 1 deletion(-)

diff --git a/drivers/net/usb/aqc111.c b/drivers/net/usb/aqc111.c
index 90061157b7ac..e197824f96f1 100644
--- a/drivers/net/usb/aqc111.c
+++ b/drivers/net/usb/aqc111.c
@@ -285,6 +285,48 @@ static void aqc111_set_phy_speed(struct usbnet *dev, u8 
autoneg, u16 speed)
                aqc111_set_phy_speed_fw_iface(dev, aqc111_data);
 }
 
+static int aqc111_change_mtu(struct net_device *net, int new_mtu)
+{
+       struct usbnet *dev = netdev_priv(net);
+       u16 reg16 = 0;
+       u8 buf[5];
+
+       net->mtu = new_mtu;
+       dev->hard_mtu = net->mtu + net->hard_header_len;
+
+       aqc111_read16_cmd(dev, AQ_ACCESS_MAC, SFR_MEDIUM_STATUS_MODE,
+                         2, &reg16);
+       if (net->mtu > 1500)
+               reg16 |= SFR_MEDIUM_JUMBO_EN;
+       else
+               reg16 &= ~SFR_MEDIUM_JUMBO_EN;
+
+       aqc111_write16_cmd(dev, AQ_ACCESS_MAC, SFR_MEDIUM_STATUS_MODE,
+                          2, &reg16);
+
+       if (dev->net->mtu > 12500 && dev->net->mtu <= 16334) {
+               memcpy(buf, &AQC111_BULKIN_SIZE[2], 5);
+               /* RX bulk configuration */
+               aqc111_write_cmd(dev, AQ_ACCESS_MAC, SFR_RX_BULKIN_QCTRL,
+                                5, 5, buf);
+       }
+
+       /* Set high low water level */
+       if (dev->net->mtu <= 4500)
+               reg16 = 0x0810;
+       else if (dev->net->mtu <= 9500)
+               reg16 = 0x1020;
+       else if (dev->net->mtu <= 12500)
+               reg16 = 0x1420;
+       else if (dev->net->mtu <= 16334)
+               reg16 = 0x1A20;
+
+       aqc111_write16_cmd(dev, AQ_ACCESS_MAC, SFR_PAUSE_WATERLVL_LOW,
+                          2, &reg16);
+
+       return 0;
+}
+
 static int aqc111_set_mac_addr(struct net_device *net, void *p)
 {
        struct usbnet *dev = netdev_priv(net);
@@ -305,6 +347,7 @@ static const struct net_device_ops aqc111_netdev_ops = {
        .ndo_start_xmit         = usbnet_start_xmit,
        .ndo_tx_timeout         = usbnet_tx_timeout,
        .ndo_get_stats64        = usbnet_get_stats64,
+       .ndo_change_mtu         = aqc111_change_mtu,
        .ndo_set_mac_address    = aqc111_set_mac_addr,
        .ndo_validate_addr      = eth_validate_addr,
 };
@@ -383,6 +426,8 @@ static int aqc111_bind(struct usbnet *dev, struct 
usb_interface *intf)
        dev->net->needed_headroom += sizeof(u64);
        dev->net->needed_tailroom += sizeof(u64);
 
+       dev->net->max_mtu = 16334;
+
        dev->net->netdev_ops = &aqc111_netdev_ops;
 
        if (usb_device_no_sg_constraint(dev->udev))
@@ -524,12 +569,22 @@ static void aqc111_configure_rx(struct usbnet *dev,
                break;
        }
 
+       if (dev->net->mtu > 12500 && dev->net->mtu <= 16334)
+               queue_num = 2; /* For Jumbo packet 16KB */
+
        memcpy(buf, &AQC111_BULKIN_SIZE[queue_num], 5);
        /* RX bulk configuration */
        aqc111_write_cmd(dev, AQ_ACCESS_MAC, SFR_RX_BULKIN_QCTRL, 5, 5, buf);
 
        /* Set high low water level */
-       reg16 = 0x0810;
+       if (dev->net->mtu <= 4500)
+               reg16 = 0x0810;
+       else if (dev->net->mtu <= 9500)
+               reg16 = 0x1020;
+       else if (dev->net->mtu <= 12500)
+               reg16 = 0x1420;
+       else if (dev->net->mtu <= 16334)
+               reg16 = 0x1A20;
 
        aqc111_write16_cmd(dev, AQ_ACCESS_MAC, SFR_PAUSE_WATERLVL_LOW,
                           2, &reg16);
@@ -604,6 +659,9 @@ static int aqc111_link_reset(struct usbnet *dev)
                aqc111_read16_cmd(dev, AQ_ACCESS_MAC, SFR_MEDIUM_STATUS_MODE,
                                  2, &reg16);
 
+               if (dev->net->mtu > 1500)
+                       reg16 |= SFR_MEDIUM_JUMBO_EN;
+
                reg16 |= SFR_MEDIUM_RECEIVE_EN | SFR_MEDIUM_RXFLOW_CTRLEN |
                         SFR_MEDIUM_TXFLOW_CTRLEN;
                aqc111_write16_cmd(dev, AQ_ACCESS_MAC, SFR_MEDIUM_STATUS_MODE,
-- 
2.7.4