[PATCH 04/10] clk: implement parent pass through functions

[Uwe Kleine-König]

On Fri, Apr 15, 2011 at 09:08:09PM +0200, Sascha Hauer wrote:
> A common case for clocks is that certain operations are not implemented
> and shall be passed through to the parent. Add convenience functions
> for this purpose
> 
> Signed-off-by: Sascha Hauer <s.hauer at pengutronix.de>
> Cc: Jeremy Kerr <jeremy.kerr at canonical.com>
> ---
>  drivers/clk/clk.c   |   77 +++++++++++++++++++++++++++++++++++++++++++++++++++
>  include/linux/clk.h |    9 ++++++
>  2 files changed, 86 insertions(+), 0 deletions(-)
> 
> diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c
> index 264c809..7e2c182 100644
> --- a/drivers/clk/clk.c
> +++ b/drivers/clk/clk.c
> @@ -171,3 +171,80 @@ struct clk_ops clk_fixed_ops = {
>  	.get_rate = clk_fixed_get_rate,
>  };
>  EXPORT_SYMBOL_GPL(clk_fixed_ops);
> +
> +int clk_parent_prepare(struct clk *clk)
> +{
> +	struct clk *parent = clk_get_parent(clk);
> +
> +	if (IS_ERR(parent))
> +		return -ENOSYS;
> +
> +	return clk_prepare(parent);
> +}
> +EXPORT_SYMBOL_GPL(clk_parent_prepare);
> +
> +void clk_parent_unprepare(struct clk *clk)
> +{
> +	struct clk *parent = clk_get_parent(clk);
> +
> +	if (IS_ERR(parent))
> +		return;
> +
> +	clk_unprepare(parent);
> +}
> +EXPORT_SYMBOL_GPL(clk_parent_unprepare);
> +
> +int clk_parent_enable(struct clk *clk)
> +{
> +	struct clk *parent = clk_get_parent(clk);
> +
> +	if (IS_ERR(parent))
> +		return 0;
Do you really want to return 0 here? IMHO something is fishy if a clock
has .enable = clk_parent_enable but has no parent.

> +
> +	return clk_enable(parent);
> +}
> +EXPORT_SYMBOL_GPL(clk_parent_enable);
> +
> +void clk_parent_disable(struct clk *clk)
> +{
> +	struct clk *parent = clk_get_parent(clk);
> +
> +	if (IS_ERR(parent))
> +		return;
> +
> +	clk_disable(parent);
> +}
> +EXPORT_SYMBOL_GPL(clk_parent_disable);
> +
> +unsigned long clk_parent_get_rate(struct clk *clk)
> +{
> +	struct clk *parent = clk_get_parent(clk);
> +
> +	if (IS_ERR(parent))
> +		return 0;
> +
> +	return clk_get_rate(parent);
> +}
> +EXPORT_SYMBOL_GPL(clk_parent_get_rate);
> +
> +long clk_parent_round_rate(struct clk *clk, unsigned long rate)
> +{
> +	struct clk *parent = clk_get_parent(clk);
> +
> +	if (IS_ERR(parent))
> +		return -ENOSYS;
> +
> +	return clk_round_rate(parent, rate);
> +}
> +EXPORT_SYMBOL_GPL(clk_parent_round_rate);
> +
> +int clk_parent_set_rate(struct clk *clk, unsigned long rate)
> +{
> +	struct clk *parent = clk_get_parent(clk);
> +
> +	if (IS_ERR(parent))
> +		return -ENOSYS;
> +
> +	return clk_set_rate(parent, rate);
> +}
> +EXPORT_SYMBOL_GPL(clk_parent_set_rate);
> diff --git a/include/linux/clk.h b/include/linux/clk.h
> index d2f0db0..d014341 100644
> --- a/include/linux/clk.h
> +++ b/include/linux/clk.h
> @@ -171,6 +171,15 @@ extern struct clk_ops clk_fixed_ops;
>  #define DEFINE_CLK_FIXED(name, r) \
>  	struct clk_fixed name = INIT_CLK_FIXED(name, r)
>  
> +/* generic pass-through-to-parent functions */
> +int clk_parent_prepare(struct clk *clk);
> +void clk_parent_unprepare(struct clk *clk);
> +int clk_parent_enable(struct clk *clk);
> +void clk_parent_disable(struct clk *clk);
> +unsigned long clk_parent_get_rate(struct clk *clk);
> +long clk_parent_round_rate(struct clk *clk, unsigned long rate);
> +int clk_parent_set_rate(struct clk *clk, unsigned long rate);
> +
Technically they don't need to depend on USE_COMMON_STRUCT_CLK.

>  #else /* !CONFIG_USE_COMMON_STRUCT_CLK */
>  
>  /*
> -- 
> 1.7.4.1
> 
> 
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> 

-- 
Pengutronix e.K.                           | Uwe Kleine-König            |
Industrial Linux Solutions                 | http://www.pengutronix.de/  |