Re: [PATCH v2] clk: clk_set_parent: skip any operation if current and new parents are equal

[Ahmad Fatoum <a.fatoum@pengutronix.de>]

On 10/13/25 11:49 AM, Michael Grzeschik wrote:
> When an clk is defined with only one parent it probably has no
> set_parent function. Therefor changing the parent would return with
> -EINVAL. We check for this case and skip this function in this case.
> 
> Signed-off-by: Michael Grzeschik <m.grzeschik@pengutronix.de>

Reviewed-by: Ahmad Fatoum <a.fatoum@pengutronix.de>

Thanks,
Ahmad

> ---
>  drivers/clk/clk.c | 3 +++
>  1 file changed, 3 insertions(+)
> 
> diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c
> index 89a007a12c5..ac5b83cf8b4 100644
> --- a/drivers/clk/clk.c
> +++ b/drivers/clk/clk.c
> @@ -302,6 +302,9 @@ int clk_set_parent(struct clk *clk, struct clk *newparent)
>  	if (IS_ERR(newparent))
>  		return PTR_ERR(newparent);
>  
> +	if (newparent == curparent)
> +		return 0;
> +
>  	if (!clk->num_parents)
>  		return -EINVAL;
>  	if (!clk->ops->set_parent)

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