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[PATCH net-next v3 7/8] net: ethernet: fs_enet: simplify clock handling with devm accessors

Maxime Chevallier posted 8 patches 1 year, 3 months ago
[PATCH net-next v3 7/8] net: ethernet: fs_enet: simplify clock handling with devm accessors
Posted by Maxime Chevallier 1 year, 3 months ago 
devm_clock_get_enabled() can be used to simplify clock handling for the
PER register clock.

Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
---
 .../ethernet/freescale/fs_enet/fs_enet-main.c    | 16 ++++------------
 drivers/net/ethernet/freescale/fs_enet/fs_enet.h |  2 --
 2 files changed, 4 insertions(+), 14 deletions(-)

diff --git a/drivers/net/ethernet/freescale/fs_enet/fs_enet-main.c b/drivers/net/ethernet/freescale/fs_enet/fs_enet-main.c
index c96a6b9e1445..ec43b71c0eba 100644
--- a/drivers/net/ethernet/freescale/fs_enet/fs_enet-main.c
+++ b/drivers/net/ethernet/freescale/fs_enet/fs_enet-main.c
@@ -900,14 +900,9 @@ static int fs_enet_probe(struct platform_device *ofdev)
 	 * but require enable to succeed when a clock was specified/found,
 	 * keep a reference to the clock upon successful acquisition
 	 */
-	clk = devm_clk_get(&ofdev->dev, "per");
-	if (!IS_ERR(clk)) {
-		ret = clk_prepare_enable(clk);
-		if (ret)
-			goto out_deregister_fixed_link;
-
-		fpi->clk_per = clk;
-	}
+	clk = devm_clk_get_enabled(&ofdev->dev, "per");
+	if (IS_ERR(clk))
+		goto out_deregister_fixed_link;
 
 	privsize = sizeof(*fep) +
 		   sizeof(struct sk_buff **) *
@@ -917,7 +912,7 @@ static int fs_enet_probe(struct platform_device *ofdev)
 	ndev = alloc_etherdev(privsize);
 	if (!ndev) {
 		ret = -ENOMEM;
-		goto out_put;
+		goto out_deregister_fixed_link;
 	}
 
 	SET_NETDEV_DEV(ndev, &ofdev->dev);
@@ -979,8 +974,6 @@ static int fs_enet_probe(struct platform_device *ofdev)
 	fep->ops->cleanup_data(ndev);
 out_free_dev:
 	free_netdev(ndev);
-out_put:
-	clk_disable_unprepare(fpi->clk_per);
 out_deregister_fixed_link:
 	of_node_put(fpi->phy_node);
 	if (of_phy_is_fixed_link(ofdev->dev.of_node))
@@ -1001,7 +994,6 @@ static void fs_enet_remove(struct platform_device *ofdev)
 	fep->ops->cleanup_data(ndev);
 	dev_set_drvdata(fep->dev, NULL);
 	of_node_put(fep->fpi->phy_node);
-	clk_disable_unprepare(fep->fpi->clk_per);
 	if (of_phy_is_fixed_link(ofdev->dev.of_node))
 		of_phy_deregister_fixed_link(ofdev->dev.of_node);
 	free_netdev(ndev);
diff --git a/drivers/net/ethernet/freescale/fs_enet/fs_enet.h b/drivers/net/ethernet/freescale/fs_enet/fs_enet.h
index ee49749a3202..6ebb1b4404c7 100644
--- a/drivers/net/ethernet/freescale/fs_enet/fs_enet.h
+++ b/drivers/net/ethernet/freescale/fs_enet/fs_enet.h
@@ -119,8 +119,6 @@ struct fs_platform_info {
 	int napi_weight;	/* NAPI weight			*/
 
 	int use_rmii;		/* use RMII mode		*/
-
-	struct clk *clk_per;	/* 'per' clock for register access */
 };
 
 struct fs_enet_private {
-- 
2.46.0
Re: [PATCH net-next v3 7/8] net: ethernet: fs_enet: simplify clock handling with devm accessors
Posted by Christophe JAILLET 1 year, 3 months ago 
Le 04/09/2024 à 19:18, Maxime Chevallier a écrit :
> devm_clock_get_enabled() can be used to simplify clock handling for the
> PER register clock.
> 
> Reviewed-by: Andrew Lunn <andrew@lunn.ch>
> Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
> ---
>   .../ethernet/freescale/fs_enet/fs_enet-main.c    | 16 ++++------------
>   drivers/net/ethernet/freescale/fs_enet/fs_enet.h |  2 --
>   2 files changed, 4 insertions(+), 14 deletions(-)
> 
> diff --git a/drivers/net/ethernet/freescale/fs_enet/fs_enet-main.c b/drivers/net/ethernet/freescale/fs_enet/fs_enet-main.c
> index c96a6b9e1445..ec43b71c0eba 100644
> --- a/drivers/net/ethernet/freescale/fs_enet/fs_enet-main.c
> +++ b/drivers/net/ethernet/freescale/fs_enet/fs_enet-main.c
> @@ -900,14 +900,9 @@ static int fs_enet_probe(struct platform_device *ofdev)
>   	 * but require enable to succeed when a clock was specified/found,
>   	 * keep a reference to the clock upon successful acquisition
>   	 */
> -	clk = devm_clk_get(&ofdev->dev, "per");
> -	if (!IS_ERR(clk)) {
> -		ret = clk_prepare_enable(clk);
> -		if (ret)
> -			goto out_deregister_fixed_link;
> -
> -		fpi->clk_per = clk;
> -	}
> +	clk = devm_clk_get_enabled(&ofdev->dev, "per");
> +	if (IS_ERR(clk))
> +		goto out_deregister_fixed_link;

Hi,

I don't know if this can lead to the same issue, but a similar change 
broke a use case in another driver. See the discussion at[1].

It ended to using devm_clk_get_optional_enabled() to keep the same 
behavior as before.

CJ

[1]: 
https://lore.kernel.org/all/20240912104630.1868285-2-ardb+git@google.com/

>   
>   	privsize = sizeof(*fep) +
>   		   sizeof(struct sk_buff **) *
> @@ -917,7 +912,7 @@ static int fs_enet_probe(struct platform_device *ofdev)
>   	ndev = alloc_etherdev(privsize);
>   	if (!ndev) {
>   		ret = -ENOMEM;
> -		goto out_put;
> +		goto out_deregister_fixed_link;
>   	}
>   
>   	SET_NETDEV_DEV(ndev, &ofdev->dev);
> @@ -979,8 +974,6 @@ static int fs_enet_probe(struct platform_device *ofdev)
>   	fep->ops->cleanup_data(ndev);
>   out_free_dev:
>   	free_netdev(ndev);
> -out_put:
> -	clk_disable_unprepare(fpi->clk_per);
>   out_deregister_fixed_link:
>   	of_node_put(fpi->phy_node);
>   	if (of_phy_is_fixed_link(ofdev->dev.of_node))
> @@ -1001,7 +994,6 @@ static void fs_enet_remove(struct platform_device *ofdev)
>   	fep->ops->cleanup_data(ndev);
>   	dev_set_drvdata(fep->dev, NULL);
>   	of_node_put(fep->fpi->phy_node);
> -	clk_disable_unprepare(fep->fpi->clk_per);
>   	if (of_phy_is_fixed_link(ofdev->dev.of_node))
>   		of_phy_deregister_fixed_link(ofdev->dev.of_node);
>   	free_netdev(ndev);
> diff --git a/drivers/net/ethernet/freescale/fs_enet/fs_enet.h b/drivers/net/ethernet/freescale/fs_enet/fs_enet.h
> index ee49749a3202..6ebb1b4404c7 100644
> --- a/drivers/net/ethernet/freescale/fs_enet/fs_enet.h
> +++ b/drivers/net/ethernet/freescale/fs_enet/fs_enet.h
> @@ -119,8 +119,6 @@ struct fs_platform_info {
>   	int napi_weight;	/* NAPI weight			*/
>   
>   	int use_rmii;		/* use RMII mode		*/
> -
> -	struct clk *clk_per;	/* 'per' clock for register access */
>   };
>   
>   struct fs_enet_private {
Re: [PATCH net-next v3 7/8] net: ethernet: fs_enet: simplify clock handling with devm accessors
Posted by Maxime Chevallier 1 year, 3 months ago 
Hello Christophe,

On Fri, 13 Sep 2024 22:24:28 +0200
Christophe JAILLET <christophe.jaillet@wanadoo.fr> wrote:

> Le 04/09/2024 à 19:18, Maxime Chevallier a écrit :
> > devm_clock_get_enabled() can be used to simplify clock handling for the
> > PER register clock.
> > 
> > Reviewed-by: Andrew Lunn <andrew@lunn.ch>
> > Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
> > ---
> >   .../ethernet/freescale/fs_enet/fs_enet-main.c    | 16 ++++------------
> >   drivers/net/ethernet/freescale/fs_enet/fs_enet.h |  2 --
> >   2 files changed, 4 insertions(+), 14 deletions(-)
> > 
> > diff --git a/drivers/net/ethernet/freescale/fs_enet/fs_enet-main.c b/drivers/net/ethernet/freescale/fs_enet/fs_enet-main.c
> > index c96a6b9e1445..ec43b71c0eba 100644
> > --- a/drivers/net/ethernet/freescale/fs_enet/fs_enet-main.c
> > +++ b/drivers/net/ethernet/freescale/fs_enet/fs_enet-main.c
> > @@ -900,14 +900,9 @@ static int fs_enet_probe(struct platform_device *ofdev)
> >   	 * but require enable to succeed when a clock was specified/found,
> >   	 * keep a reference to the clock upon successful acquisition
> >   	 */
> > -	clk = devm_clk_get(&ofdev->dev, "per");
> > -	if (!IS_ERR(clk)) {
> > -		ret = clk_prepare_enable(clk);
> > -		if (ret)
> > -			goto out_deregister_fixed_link;
> > -
> > -		fpi->clk_per = clk;
> > -	}
> > +	clk = devm_clk_get_enabled(&ofdev->dev, "per");
> > +	if (IS_ERR(clk))
> > +		goto out_deregister_fixed_link;  
> 
> Hi,
> 
> I don't know if this can lead to the same issue, but a similar change 
> broke a use case in another driver. See the discussion at[1].
> 
> It ended to using devm_clk_get_optional_enabled() to keep the same 
> behavior as before.

After digging around, there appears to be some platforms that don't
have this clock indeed. Thanks for catching this, the optional is the
way to go.

Thanks,

Maxime

Patchew 2.1-devel-b67e4c2

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