On 25 November 2014 at 09:48, amit daniel kachhap <amit.daniel@xxxxxxxxxxx> wrote: > On Tue, Nov 25, 2014 at 1:05 PM, Ulf Hansson <ulf.hansson@xxxxxxxxxx> wrote: >> On 24 November 2014 at 14:04, Amit Daniel Kachhap >> <amit.daniel@xxxxxxxxxxx> wrote: >>> This API may be needed to set the power domain parent/child relationship >>> in the power domain platform driver. The parent relationship is >>> generally set after the child power domain is registered with the power >>> domain subsystem. In this case, pm_genpd_lookup_name API might be >>> useful. >> >> I think this is a step in the wrong direction. Instead we should be >> working on removing the "name" based APIs from genpd. >> >> The proper way should be to pass the PM domain as a parameter to the >> APIs instead. > Yes i understand but i had a special requirement for using this API > during pd probe. > I cannot use hierarchy to represent parent/child pd nodes as it will > break the existing SoC's. In my case all the PD nodes are linear. The > parent/child relationship are established in the second pass after all > the PD entries are registered with the help of this API. > Although there a way that i can always keep parent PD's before the > child PD's in DT in linear order. Will check this approach. I had some thinking around this, could the below approach work? I just posted a patch[1] adding a new pm_genpd_lookup() API, which is using a "DT device node" to fetch the genpd. The idea is to use that API to get the genpd handle which is needed to configure a subdomain through pm_genpd_add_subdomain() API. In principle you will have to walk through the DT a couple of times, initialize those domains (and subdomains) which either don't have a parent domain or which parent domain already has been initialized. I guess you need a somewhat clever loop to do that, but I think it's doable. Obviously we also need to have a generic binding for a "parent domain". I like Geert's proposal from the other patch, which means using "power-domains = <&pd_xyz>". Kind regards Uffe [1] http://marc.info/?l=linux-pm&m=141709766008458&w=2 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
