Re: [PATCH v2 02/10] mfd: rz-mtu3: use device-managed reset deassert

[Lee Jones <lee@kernel.org>]

On Fri, 10 Apr 2026, Cosmin Tanislav wrote:

> Replace devm_reset_control_get_exclusive() and the manual
> reset_control_deassert()/reset_control_assert() with handling by
> devm_reset_control_get_exclusive_deasserted().
> 
> While at it, remove struct rz_mtu3_priv::rstc and use a local variable
> for it as it is not needed inside rz_mtu3_reset_assert().
> 
> Rename rz_mtu3_reset_assert() to rz_mtu3_mfd_remove() to accurately
> describe its usage since it no longer calls reset_control_assert().
> 
> Signed-off-by: Cosmin Tanislav <cosmin-gabriel.tanislav.xa@renesas.com>
> ---
> 
> V2:
>  * no changes
> 
>  drivers/mfd/rz-mtu3.c | 23 +++++++----------------
>  1 file changed, 7 insertions(+), 16 deletions(-)
> 
> diff --git a/drivers/mfd/rz-mtu3.c b/drivers/mfd/rz-mtu3.c
> index 9cdfef610398f..6b9c6831dffa9 100644
> --- a/drivers/mfd/rz-mtu3.c
> +++ b/drivers/mfd/rz-mtu3.c
> @@ -21,7 +21,6 @@
>  
>  struct rz_mtu3_priv {
>  	void __iomem *mmio;
> -	struct reset_control *rstc;
>  	spinlock_t lock;
>  };
>  
> @@ -301,13 +300,9 @@ void rz_mtu3_disable(struct rz_mtu3_channel *ch)
>  }
>  EXPORT_SYMBOL_GPL(rz_mtu3_disable);
>  
> -static void rz_mtu3_reset_assert(void *data)
> +static void rz_mtu3_mfd_remove(void *data)

Remove any mention of "mfd".

>  {
> -	struct rz_mtu3 *mtu = dev_get_drvdata(data);
> -	struct rz_mtu3_priv *priv = mtu->priv_data;
> -
>  	mfd_remove_devices(data);

Why not use devm_mfd_add_devices() instead?

> -	reset_control_assert(priv->rstc);
>  }
>  
>  static const struct mfd_cell rz_mtu3_devs[] = {
> @@ -321,6 +316,7 @@ static const struct mfd_cell rz_mtu3_devs[] = {
>  
>  static int rz_mtu3_probe(struct platform_device *pdev)
>  {
> +	struct reset_control *rstc;

This shouldn't go above the main device data structs.

>  	struct rz_mtu3_priv *priv;
>  	struct rz_mtu3 *ddata;
>  	unsigned int i;
> @@ -340,15 +336,14 @@ static int rz_mtu3_probe(struct platform_device *pdev)
>  	if (IS_ERR(priv->mmio))
>  		return PTR_ERR(priv->mmio);
>  
> -	priv->rstc = devm_reset_control_get_exclusive(&pdev->dev, NULL);
> -	if (IS_ERR(priv->rstc))
> -		return PTR_ERR(priv->rstc);
> +	rstc = devm_reset_control_get_exclusive_deasserted(&pdev->dev, NULL);
> +	if (IS_ERR(rstc))
> +		return PTR_ERR(rstc);
>  
>  	ddata->clk = devm_clk_get(&pdev->dev, NULL);
>  	if (IS_ERR(ddata->clk))
>  		return PTR_ERR(ddata->clk);
>  
> -	reset_control_deassert(priv->rstc);
>  	spin_lock_init(&priv->lock);
>  	platform_set_drvdata(pdev, ddata);
>  
> @@ -361,14 +356,10 @@ static int rz_mtu3_probe(struct platform_device *pdev)
>  	ret = mfd_add_devices(&pdev->dev, 0, rz_mtu3_devs,
>  			      ARRAY_SIZE(rz_mtu3_devs), NULL, 0, NULL);
>  	if (ret < 0)
> -		goto err_assert;
> +		return ret;
>  
> -	return devm_add_action_or_reset(&pdev->dev, rz_mtu3_reset_assert,
> +	return devm_add_action_or_reset(&pdev->dev, rz_mtu3_mfd_remove,
>  					&pdev->dev);
> -
> -err_assert:
> -	reset_control_assert(priv->rstc);
> -	return ret;
>  }
>  
>  static const struct of_device_id rz_mtu3_of_match[] = {
> -- 
> 2.53.0

-- 
Lee Jones