Re: [PATCH 2/3] soc: rockchip: power-domain: Use of_clk_get_parent_count() instead of open coding

[Heiko Stuebner <heiko@sntech.de>]

Hi Geert,

Am Freitag, 19. Januar 2018, 16:18:20 CET schrieb Geert Uytterhoeven:
> As of_clk_get_parent_count() returns zero on failure, while
> of_count_phandle_with_args() might return a negative error code, this
> also fixes the issue of possibly using a negative number in the
> allocation below.
> 
> Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
> ---
>  drivers/soc/rockchip/pm_domains.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/soc/rockchip/pm_domains.c b/drivers/soc/rockchip/pm_domains.c
> index 5c342167b9db7a16..9936038d38771784 100644
> --- a/drivers/soc/rockchip/pm_domains.c
> +++ b/drivers/soc/rockchip/pm_domains.c
> @@ -16,6 +16,7 @@
>  #include <linux/of_address.h>
>  #include <linux/of_platform.h>
>  #include <linux/clk.h>
> +#include <linux/clk-provider.h>

not wanting to be to nitpicky, but clk-provider.h seems that it should be
used from drivers exposing clocks to the system, not from clock users.

I just remember that in the past clk maintainers tried to keep their
layering intact, so I've included them for clarification.

Mike, Stephen: the power-domain driver of Rockchip socs needs
to toggle all clocks of domain peripherals when turning a domain
on or off, so has a variable list of clocks in the clocks property in dt.
Hence the of_count_... call which could be replaced with
of_clk_get_parent_count to not open-code this.


Heiko

>  #include <linux/regmap.h>
>  #include <linux/mfd/syscon.h>
>  #include <dt-bindings/power/rk3288-power.h>
> @@ -391,7 +392,7 @@ static int rockchip_pm_add_one_domain(struct rockchip_pmu *pmu,
>  		return -EINVAL;
>  	}
>  
> -	clk_cnt = of_count_phandle_with_args(node, "clocks", "#clock-cells");
> +	clk_cnt = of_clk_get_parent_count(node);
>  	pd = devm_kzalloc(pmu->dev,
>  			  sizeof(*pd) + clk_cnt * sizeof(pd->clks[0]),
>  			  GFP_KERNEL);
>