[PATCH 1/2] clk: implement clk_get_enabled helper

[Sascha Hauer]

On Wed, Sep 13, 2023 at 02:08:06PM +0200, Ahmad Fatoum wrote:
> Kernel code increasingly uses devm_clk_get_enabled to make driver code
> more compact. Port a devres-less version to barebox to make porting such
> Linux code easier.
> 
> Signed-off-by: Ahmad Fatoum <a.fatoum at pengutronix.de>
> ---
>  include/linux/clk.h | 29 +++++++++++++++++++++++++++++
>  1 file changed, 29 insertions(+)
> 
> diff --git a/include/linux/clk.h b/include/linux/clk.h
> index 82022e78e39d..398427eca676 100644
> --- a/include/linux/clk.h
> +++ b/include/linux/clk.h
> @@ -951,4 +951,33 @@ static inline struct clk *clk_get_optional(struct device *dev, const char *id)
>  	return clk;
>  }
>  
> +/**
> + * clk_get_enabled - clk_get() + clk_prepare_enable()
> + * @dev: device for clock "consumer"
> + * @id: clock consumer ID
> + *
> + * Return: a struct clk corresponding to the clock producer, or
> + * valid IS_ERR() condition containing errno.  The implementation
> + * uses @dev and @id to determine the clock consumer, and thereby
> + * the clock producer.  (IOW, @id may be identical strings, but
> + * clk_get may return different clock producers depending on @dev.)
> + *
> + * The returned clk (if valid) is enabled.
> + */
> +static inline struct clk *clk_get_enabled(struct device *dev, const char *id)
> +{
> +	struct clk *clk;
> +	int ret;
> +
> +	clk = clk_get(dev, id);
> +	if (IS_ERR(clk))
> +		return clk;
> +
> +	ret = clk_enable(clk);
> +	if (ret)
> +		return ERR_PTR(ret);

As this isn't devm managed you should release the clock in the error
path.

Sascha

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