Re: [PATCH v2] net: ethernet: support "fixed-link" DT key/node on nb8800 driver

[Sebastian Frias]

On 02/05/2016 02:58 PM, Måns Rullgård wrote:
Sebastian Frias <s...@laposte.net> writes:
Signed-off-by: Sebastian Frias <s...@laposte.net>
---
  drivers/net/ethernet/aurora/nb8800.c | 15 ++++++++++++---
  1 file changed, 12 insertions(+), 3 deletions(-)

diff --git a/drivers/net/ethernet/aurora/nb8800.c
b/drivers/net/ethernet/aurora/nb8800.c
index ecc4a33..dd7bedc 100644
--- a/drivers/net/ethernet/aurora/nb8800.c
+++ b/drivers/net/ethernet/aurora/nb8800.c
@@ -1462,9 +1462,18 @@ static int nb8800_probe(struct platform_device *pdev)

        priv->phy_node = of_parse_phandle(pdev->dev.of_node, "phy-handle", 0);
        if (!priv->phy_node) {
-               dev_err(&pdev->dev, "no PHY specified\n");
-               ret = -ENODEV;
-               goto err_free_bus;
+               if (of_phy_is_fixed_link(pdev->dev.of_node)) {
+                       ret = of_phy_register_fixed_link(pdev->dev.of_node);
+                       if (ret < 0) {
+                               dev_err(&pdev->dev, "bad fixed-link spec\n");
+                               goto err_free_bus;
+                       }
+                       priv->phy_node = of_node_get(pdev->dev.of_node);
+               } else {
+                       dev_err(&pdev->dev, "no PHY specified\n");
+                       ret = -ENODEV;
+                       goto err_free_bus;
+               }
        }

Maybe it would be clearer to reduce the if() nesting a bit, like this
for instance:

        if (of_phy_is_fixed_link(pdev->dev.of_node)) {
                ret = of_phy_register_fixed_link(pdev->dev.of_node);
                if (ret < 0) {
                        dev_err(&pdev->dev, "bad fixed-link spec\n");
                        goto err_free_bus;
                }
                priv->phy_node = of_node_get(pdev->dev.of_node);
        }

        if (!priv->phy_node)
                priv->phy_node = of_parse_phandle(pdev->dev.of_node,
                                                  "phy-handle", 0);

        if (!priv->phy_node) {
                dev_err(&pdev->dev, "no PHY specified\n");
                ret = -ENODEV;
                goto err_free_bus;
        }



Thanks Måns for your comments.
With old code + my patch, we only hit 1 comparison in the general case, 
and a 2nd one in "fixed-link" case.
With your suggestion above, it would mean that we hit 3 comparisons all 
the time.
If you are ok with the 3 comparisons, I can post a v3.