Re: [PATCH v3 4/5] soc: rockchip: power-domain: Add GENPD_FLAG_RPM_ALWAYS_ON support

From: Ulf Hansson
Date: Wed Oct 09 2024 - 09:24:19 EST


On Tue, 8 Oct 2024 at 08:16, Shawn Lin <shawn.lin@xxxxxxxxxxxxxx> wrote:
>
> If low level driver claims to keep its own power domain always on,
> let pd driver respect the flag of GENPD_FLAG_RPM_ALWAYS_ON.
>
> Signed-off-by: Shawn Lin <shawn.lin@xxxxxxxxxxxxxx>
> ---
>
> Changes in v3: None
> Changes in v2: None
>
> drivers/pmdomain/rockchip/pm-domains.c | 3 +++
> 1 file changed, 3 insertions(+)
>
> diff --git a/drivers/pmdomain/rockchip/pm-domains.c b/drivers/pmdomain/rockchip/pm-domains.c
> index cb0f938..b2bb458 100644
> --- a/drivers/pmdomain/rockchip/pm-domains.c
> +++ b/drivers/pmdomain/rockchip/pm-domains.c
> @@ -621,6 +621,9 @@ static int rockchip_pd_power_off(struct generic_pm_domain *domain)
> {
> struct rockchip_pm_domain *pd = to_rockchip_pd(domain);
>
> + if (pd->genpd.flags & GENPD_FLAG_RPM_ALWAYS_ON)
> + return 0;

During system suspend, genpd may try to power off the PM domains that
have the GENPD_FLAG_RPM_ALWAYS_ON being set.

It seems like you need to prevent the PM domains from being power off
during system suspend too, right? In that case, why not use
GENPD_FLAG_ALWAYS_ON instead?

Or maybe the use case is different, let's continue to discuss patch5 first.

> +
> return rockchip_pd_power(pd, false);
> }
>
> --
> 2.7.4
>

Kind regards
Uffe