[PATCH 1/2 v2] imx: optimize __clk_enable() and __clk_disable() functions.

[Vladimir Zapolskiy]

On Thu, Mar 18, 2010 at 4:27 PM, Vladimir Zapolskiy
<vzapolskiy at gmail.com> wrote:
> To remove unnecessary calls of functions with invalid argumets make
> the checks before a call.
>
> Signed-off-by: Vladimir Zapolskiy <vzapolskiy at gmail.com>
> ---
>  arch/arm/plat-mxc/clock.c |   25 ++++++++++++-------------
>  1 files changed, 12 insertions(+), 13 deletions(-)
>
> diff --git a/arch/arm/plat-mxc/clock.c b/arch/arm/plat-mxc/clock.c
> index 323ff8c..ec4af90 100644
> --- a/arch/arm/plat-mxc/clock.c
> +++ b/arch/arm/plat-mxc/clock.c
> @@ -50,24 +50,25 @@ static DEFINE_MUTEX(clocks_mutex);
>
>  static void __clk_disable(struct clk *clk)
>  {
> -       if (clk == NULL || IS_ERR(clk))
> -               return;
> -
> -       __clk_disable(clk->parent);
> -       __clk_disable(clk->secondary);
> -
>        WARN_ON(!clk->usecount);
> +
>        if (!(--clk->usecount) && clk->disable)
>                clk->disable(clk);
> +
> +       if (clk->secondary)
> +               __clk_disable(clk->secondary);
> +
> +       if (clk->parent)
> +               __clk_disable(clk->parent);
>  }
>
>  static int __clk_enable(struct clk *clk)
>  {
> -       if (clk == NULL || IS_ERR(clk))
> -               return -EINVAL;
> +       if (clk->parent)
> +               __clk_enable(clk->parent);
>
> -       __clk_enable(clk->parent);
> -       __clk_enable(clk->secondary);
> +       if (clk->secondary)
> +               __clk_enable(clk->secondary);
>
>        if (clk->usecount++ == 0 && clk->enable)
>                clk->enable(clk);
> @@ -99,9 +100,7 @@ EXPORT_SYMBOL(clk_enable);
>  */
>  void clk_disable(struct clk *clk)
>  {
> -       if (clk == NULL || IS_ERR(clk))
> -               return;
> -
> +       BUG_ON(clk == NULL || IS_ERR(clk));
>        mutex_lock(&clocks_mutex);
>        __clk_disable(clk);
>        mutex_unlock(&clocks_mutex);
> --
> 1.6.6.1
>
>
One potential issue is still exists, there is no valid checks and
unbinding of return values in __clk_enable() recursive calls.

With best wishes,
Vladimir