Re: [PATCH] PM / Domains: If an OF node is found but no device probed yet, defer.
From: Ulf Hansson
Date: Thu Mar 12 2015 - 04:39:59 EST
On 11 March 2015 at 16:27, Eric Anholt <eric@xxxxxxxxxx> wrote:
> If we've declared a power domain in the OF, and the OF node is found
> but the requested domain hasn't been registered on it yet, then we
> probably have just tried to probe before the power domain driver has.
> Defer our device's probe until it shows up.
As Geert also pointed out in his reply; I think the proper solution is
to move the registration of the PM domain to an earlier init level.
The main reason from my side is that I don't want us to invent yet
another "probe scenario", since we currently already have some
difficulties to handle the existing ones. Like the issue below.
> Signed-off-by: Eric Anholt <eric@xxxxxxxxxx>
> I ran into this when turning my ad-hoc code for BCM2835 (Raspberry Pi)
> USB poweron support in the DWC2 controller to an OF-based power domain
> drivers/base/power/domain.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
> diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c
> index ba4abbe..2b93c98 100644
> --- a/drivers/base/power/domain.c
> +++ b/drivers/base/power/domain.c
> @@ -2064,7 +2064,7 @@ EXPORT_SYMBOL_GPL(of_genpd_del_provider);
> struct generic_pm_domain *of_genpd_get_from_provider(
> struct of_phandle_args *genpdspec)
> - struct generic_pm_domain *genpd = ERR_PTR(-ENOENT);
> + struct generic_pm_domain *genpd = ERR_PTR(-EPROBE_DEFER);
> struct of_genpd_provider *provider;
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