Re: [RESEND,2/7] ARM: Exynos: add support for sub-power domains

[Pankaj Dubey <pankaj.dubey@samsung.com>]

+CC: Amit Daniel Kachhap

Hi Andrzej,

On Monday 24 November 2014 01:00 PM, Andrzej Hajda wrote:
> From: Marek Szyprowski <m.szyprowski@samsung.com>
>
> This patch adds support for making one power domain a sub-domain of
> other domain. This is useful for modeling power dependences for devices
> like TV Mixer or Camera ISP, which needs to have more than one power
> domain enabled to be operational.
>
> Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
> Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
>
> ---
> Documentation/devicetree/bindings/arm/exynos/power_domain.txt | 2 ++
>   arch/arm/mach-exynos/pm_domains.c                             | 9 ++++++++-
>   2 files changed, 10 insertions(+), 1 deletion(-)
>
> diff --git a/Documentation/devicetree/bindings/arm/exynos/power_domain.txt b/Documentation/devicetree/bindings/arm/exynos/power_domain.txt
> index abde1ea..cad9476 100644
> --- a/Documentation/devicetree/bindings/arm/exynos/power_domain.txt
> +++ b/Documentation/devicetree/bindings/arm/exynos/power_domain.txt
> @@ -22,6 +22,8 @@ Optional Properties:
>   	- pclkN, clkN: Pairs of parent of input clock and input clock to the
>   		devices in this power domain. Maximum of 4 pairs (N = 0 to 3)
>   		are supported currently.
> +- power-domain-master: phandle to a master power domain that the given domain
> +		       is a part of
>

If you are trying to make parent, child relationship using this, please 
have a look to following thread [1] where Amit also trying to make such 
attempt and some discussion are happening on this thread, so that we can 
come up with single approach for all such needs.

[1]: https://patchwork.kernel.org/patch/5366171/

Thanks,
Pankaj Dubey

>   Node of a device using power domains must have a samsung,power-domain property
>   defined with a phandle to respective power domain.
> diff --git a/arch/arm/mach-exynos/pm_domains.c b/arch/arm/mach-exynos/pm_domains.c
> index 20f2671..373ac62 100644
> --- a/arch/arm/mach-exynos/pm_domains.c
> +++ b/arch/arm/mach-exynos/pm_domains.c
> @@ -108,7 +108,7 @@ static int exynos_pd_power_off(struct generic_pm_domain *domain)
>   static __init int exynos4_pm_init_power_domain(void)
>   {
>   	struct platform_device *pdev;
> -	struct device_node *np;
> +	struct device_node *np, *master_np;
>
>   	for_each_compatible_node(np, NULL, "samsung,exynos4210-pd") {
>   		struct exynos_pm_domain *pd;
> @@ -159,6 +159,13 @@ no_clk:
>
>   		pm_genpd_init(&pd->pd, NULL, !on);
>   		of_genpd_add_provider_simple(np, &pd->pd);
> +
> +		/* make master and slave hierarchy */
> +		master_np = of_parse_phandle(np, "power-domain-master", 0);
> +		if (master_np) {
> +			pm_genpd_add_subdomain_names(master_np->name, np->name);
> +			of_node_put(master_np);
> +		}
>   	}
>
>   	return 0;
>