The driver use the value of property 'snps,rx-queues-to-use' to loop
same numbers child nodes as queues, such as:

    gmac {
        rx-queues-config {
            snps,rx-queues-to-use = <1>;
            queue0 {
                // nothing need here.
	    };
	};
    };

Since a patch for dtc from rockchip will delete all node without any
properties or child node, the queue0 node will be deleted, that caused
the driver fail to probe:

    rk_gmac-dwmac: probe of ffa80000.ethernet failed with error -22

This patch try to support driver work well for DTs without setting for
the child queue nodes and then have none child queue nodes.

Signed-off-by: Jianqun Xu <jay.xu@rock-chips.com>
---
v2:
 - change subject and update commit comment, sugguested by Kicinski

 drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c
index 2d8c095f3856..4f01a41c485c 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c
@@ -279,7 +279,7 @@ static int stmmac_mtl_setup(struct platform_device *pdev,
 
 		queue++;
 	}
-	if (queue != plat->tx_queues_to_use) {
+	if (queue != plat->tx_queues_to_use && of_get_child_count(tx_node)) {
 		ret = -EINVAL;
 		dev_err(&pdev->dev, "Not all TX queues were configured\n");
 		goto out;
-- 
2.25.1

On Fri, 29 Apr 2022 08:46:05 +0800 Jianqun Xu wrote:
> The driver use the value of property 'snps,rx-queues-to-use' to loop
> same numbers child nodes as queues, such as:
> 
>     gmac {
>         rx-queues-config {
>             snps,rx-queues-to-use = <1>;
>             queue0 {
>                 // nothing need here.
> 	    };
> 	};
>     };

I think you mean tx, not rx, given the code.

>  
>  		queue++;
>  	}
> -	if (queue != plat->tx_queues_to_use) {
> +	if (queue != plat->tx_queues_to_use && of_get_child_count(tx_node)) {
>  		ret = -EINVAL;
>  		dev_err(&pdev->dev, "Not all TX queues were configured\n");
>  		goto out;

Also what about the init to defaults I asked about?

On Fri, Apr 29, 2022 at 08:46:05AM +0800, Jianqun Xu wrote:
> The driver use the value of property 'snps,rx-queues-to-use' to loop
> same numbers child nodes as queues, such as:
> 
>     gmac {
>         rx-queues-config {
>             snps,rx-queues-to-use = <1>;
>             queue0 {
>                 // nothing need here.
> 	    };
> 	};
>     };
> 
> Since a patch for dtc from rockchip will delete all node without any
> properties or child node, the queue0 node will be deleted, that caused
> the driver fail to probe:

Is this the in tree dtc? Do you have a commit hash for it? That should
probably be used as a Fixes: tag. Or that change to dtc needs
reverting because it breaks stuff.

	  Andrew