[RFC PATCH v1] net: ethernet: nb8800: Reset HW block in ndo_open

[Marc Gonzalez]

ndo_stop breaks RX in a way that ndo_open is unable to undo.
Work around the issue by resetting the HW in ndo_open.
This will provide the basis for suspend/resume support.

Signed-off-by: Marc Gonzalez <marc_gonza...@sigmadesigns.com>
---
 drivers/net/ethernet/aurora/nb8800.c | 40 +++++++++++++++++-------------------
 drivers/net/ethernet/aurora/nb8800.h |  1 +
 2 files changed, 20 insertions(+), 21 deletions(-)

diff --git a/drivers/net/ethernet/aurora/nb8800.c 
b/drivers/net/ethernet/aurora/nb8800.c
index e94159507847..954a28542c3b 100644
--- a/drivers/net/ethernet/aurora/nb8800.c
+++ b/drivers/net/ethernet/aurora/nb8800.c
@@ -39,6 +39,7 @@
 
 #include "nb8800.h"
 
+static void nb8800_init(struct net_device *dev);
 static void nb8800_tx_done(struct net_device *dev);
 static int nb8800_dma_stop(struct net_device *dev);
 
@@ -957,6 +958,8 @@ static int nb8800_open(struct net_device *dev)
        struct phy_device *phydev;
        int err;
 
+       nb8800_init(dev);
+
        /* clear any pending interrupts */
        nb8800_writel(priv, NB8800_RXC_SR, 0xf);
        nb8800_writel(priv, NB8800_TXC_SR, 0xf);
@@ -1350,6 +1353,20 @@ static const struct of_device_id nb8800_dt_ids[] = {
 };
 MODULE_DEVICE_TABLE(of, nb8800_dt_ids);
 
+static void nb8800_init(struct net_device *dev)
+{
+       struct nb8800_priv *priv = netdev_priv(dev);
+       const struct nb8800_ops *ops = priv->ops;
+
+       if (ops && ops->reset)
+               ops->reset(dev);
+       nb8800_hw_init(dev);
+       if (ops && ops->init)
+               ops->init(dev);
+       nb8800_update_mac_addr(dev);
+       priv->speed = 0;
+}
+
 static int nb8800_probe(struct platform_device *pdev)
 {
        const struct of_device_id *match;
@@ -1389,6 +1406,7 @@ static int nb8800_probe(struct platform_device *pdev)
 
        priv = netdev_priv(dev);
        priv->base = base;
+       priv->ops = ops;
 
        priv->phy_mode = of_get_phy_mode(pdev->dev.of_node);
        if (priv->phy_mode < 0)
@@ -1407,12 +1425,6 @@ static int nb8800_probe(struct platform_device *pdev)
 
        spin_lock_init(&priv->tx_lock);
 
-       if (ops && ops->reset) {
-               ret = ops->reset(dev);
-               if (ret)
-                       goto err_disable_clk;
-       }
-
        bus = devm_mdiobus_alloc(&pdev->dev);
        if (!bus) {
                ret = -ENOMEM;
@@ -1454,16 +1466,6 @@ static int nb8800_probe(struct platform_device *pdev)
 
        priv->mii_bus = bus;
 
-       ret = nb8800_hw_init(dev);
-       if (ret)
-               goto err_deregister_fixed_link;
-
-       if (ops && ops->init) {
-               ret = ops->init(dev);
-               if (ret)
-                       goto err_deregister_fixed_link;
-       }
-
        dev->netdev_ops = &nb8800_netdev_ops;
        dev->ethtool_ops = &nb8800_ethtool_ops;
        dev->flags |= IFF_MULTICAST;
@@ -1476,14 +1478,12 @@ static int nb8800_probe(struct platform_device *pdev)
        if (!is_valid_ether_addr(dev->dev_addr))
                eth_hw_addr_random(dev);
 
-       nb8800_update_mac_addr(dev);
-
        netif_carrier_off(dev);
 
        ret = register_netdev(dev);
        if (ret) {
                netdev_err(dev, "failed to register netdev\n");
-               goto err_free_dma;
+               goto err_deregister_fixed_link;
        }
 
        netif_napi_add(dev, &priv->napi, nb8800_poll, NAPI_POLL_WEIGHT);
@@ -1492,8 +1492,6 @@ static int nb8800_probe(struct platform_device *pdev)
 
        return 0;
 
-err_free_dma:
-       nb8800_dma_free(dev);
 err_deregister_fixed_link:
        if (of_phy_is_fixed_link(pdev->dev.of_node))
                of_phy_deregister_fixed_link(pdev->dev.of_node);
diff --git a/drivers/net/ethernet/aurora/nb8800.h 
b/drivers/net/ethernet/aurora/nb8800.h
index 6ec4a956e1e5..d5f4481a2c7b 100644
--- a/drivers/net/ethernet/aurora/nb8800.h
+++ b/drivers/net/ethernet/aurora/nb8800.h
@@ -305,6 +305,7 @@ struct nb8800_priv {
        dma_addr_t                      tx_desc_dma;
 
        struct clk                      *clk;
+       const struct nb8800_ops         *ops;
 };
 
 struct nb8800_ops {
-- 
2.11.0