Re: [PATCH 1/2] clk: implement clk_get_enabled helper

[Sascha Hauer <sha@pengutronix.de>]

On Thu, Sep 14, 2023 at 09:46:40AM +0200, Sascha Hauer wrote:
> 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@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.

Oh, our clk_put() implementation is a no-op ;)
Added a clk_put() while applying anyway.

Sascha

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