3) How do we handle devices that already have power-domains specified in DT? The opp binding for required-opps doesn't let us specify the power domain to target, instead it assumes that whatever power domain is attached to a device is the one that OPP needs to use to change the genpd performance state. Do we need a dev_pm_opp_set_required_opps_name() or something to be explicit about this? Can we have some way for the power domain that required-opps correspond to be expressed in the OPP tables themselves?
I was converting a few more drivers to use the proposed approach in this RFC, in order to identify all outstanding issues we need to deal with, and specifically for UFS, I end up with this exact scenario where UFS already has an existing power domain (gdsc) and I need to add another one (rpmhpd) for setting the performance state. If I use dev_pm_opp_of_add_table() to add the opp table from DT, the opp layer assumes its the same device on which it can do a dev_pm_genpd_set_performance_state() with, however the device that's actually associated with the pm_domain when we have multiple power domains is infact the one (dummy) that we create when the driver makes a call to dev_pm_domain_attach_by_name/id(). Any thoughts on whats a good way to handle this? -- QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by The Linux Foundation
