This patch is syncing driver with actual devicetree documentation:
Documentation/devicetree/bindings/net/qca,ar71xx.txt
|Optional subnodes:
|- mdio : specifies the mdio bus, used as a container for phy nodes
| according to phy.txt in the same directory
The driver was working with fixed phy without any noticeable issues. This bug
was uncovered by introducing dsa ar9331-switch driver.
Since no one reported this bug until now, I assume no body is using it
and this patch should not brake existing system.
Fixes: d51b6ce441d3 ("net: ethernet: add ag71xx driver")
Signed-off-by: Oleksij Rempel <[email protected]>
---
drivers/net/ethernet/atheros/ag71xx.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)
diff --git a/drivers/net/ethernet/atheros/ag71xx.c b/drivers/net/ethernet/atheros/ag71xx.c
index 6703960c7cf5..d1101eea15c2 100644
--- a/drivers/net/ethernet/atheros/ag71xx.c
+++ b/drivers/net/ethernet/atheros/ag71xx.c
@@ -526,7 +526,7 @@ static int ag71xx_mdio_probe(struct ag71xx *ag)
struct device *dev = &ag->pdev->dev;
struct net_device *ndev = ag->ndev;
static struct mii_bus *mii_bus;
- struct device_node *np;
+ struct device_node *np, *mnp;
int err;
np = dev->of_node;
@@ -571,7 +571,9 @@ static int ag71xx_mdio_probe(struct ag71xx *ag)
msleep(200);
}
- err = of_mdiobus_register(mii_bus, np);
+ mnp = of_get_child_by_name(np, "mdio");
+ err = of_mdiobus_register(mii_bus, mnp);
+ of_node_put(mnp);
if (err)
goto mdio_err_put_clk;
--
2.23.0
From: Oleksij Rempel <[email protected]>
Date: Tue, 1 Oct 2019 08:41:47 +0200
> @@ -571,7 +571,9 @@ static int ag71xx_mdio_probe(struct ag71xx *ag)
> msleep(200);
> }
>
> - err = of_mdiobus_register(mii_bus, np);
> + mnp = of_get_child_by_name(np, "mdio");
> + err = of_mdiobus_register(mii_bus, mnp);
of_get_child_by_name() can fail, so error checking is necessary
before you pass mnp into of_mdiobus_register().
On Tue, Oct 01, 2019 at 09:03:20AM -0700, David Miller wrote:
> From: Oleksij Rempel <[email protected]>
> Date: Tue, 1 Oct 2019 08:41:47 +0200
>
> > @@ -571,7 +571,9 @@ static int ag71xx_mdio_probe(struct ag71xx *ag)
> > msleep(200);
> > }
> >
> > - err = of_mdiobus_register(mii_bus, np);
> > + mnp = of_get_child_by_name(np, "mdio");
> > + err = of_mdiobus_register(mii_bus, mnp);
>
> of_get_child_by_name() can fail, so error checking is necessary
> before you pass mnp into of_mdiobus_register().
Hi David
/**
* of_get_child_by_name - Find the child node by name for a given parent
* @node: parent node
* @name: child name to look for.
*
* This function looks for child node for given matching name
*
* Returns a node pointer if found, with refcount incremented, use
* of_node_put() on it when done.
* Returns NULL if node is not found.
*/
So on error, it returns NULL. And passing NULL to
of_mdiobus_register() is the correct thing to do if there is no DT
node. of_node_put() is also O.K. with NULL.
So this is all O.K. as is.
Reviewed-by: Andrew Lunn <[email protected]>
Andrew
From: Andrew Lunn <[email protected]>
Date: Tue, 1 Oct 2019 18:43:40 +0200
> On Tue, Oct 01, 2019 at 09:03:20AM -0700, David Miller wrote:
>> From: Oleksij Rempel <[email protected]>
>> Date: Tue, 1 Oct 2019 08:41:47 +0200
>>
>> > @@ -571,7 +571,9 @@ static int ag71xx_mdio_probe(struct ag71xx *ag)
>> > msleep(200);
>> > }
>> >
>> > - err = of_mdiobus_register(mii_bus, np);
>> > + mnp = of_get_child_by_name(np, "mdio");
>> > + err = of_mdiobus_register(mii_bus, mnp);
>>
>> of_get_child_by_name() can fail, so error checking is necessary
>> before you pass mnp into of_mdiobus_register().
>
> Hi David
>
> /**
> * of_get_child_by_name - Find the child node by name for a given parent
> * @node: parent node
> * @name: child name to look for.
> *
> * This function looks for child node for given matching name
> *
> * Returns a node pointer if found, with refcount incremented, use
> * of_node_put() on it when done.
> * Returns NULL if node is not found.
> */
>
> So on error, it returns NULL. And passing NULL to
> of_mdiobus_register() is the correct thing to do if there is no DT
> node. of_node_put() is also O.K. with NULL.
>
> So this is all O.K. as is.
>
> Reviewed-by: Andrew Lunn <[email protected]>
Aha I didn't think about it that way...
Ok I'll apply this thanks.