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I'm creating platform device for the clocks that require DVFS. These clocks don't use regulator, they are attached to the CORE domain. GENPD framework manages the performance state, aggregating perf votes from each device, i.e. from each clock individually.
You want to reinvent another layer of aggregation on top of GENPD. This doesn't worth the effort, we won't get anything from it, it should be a lot of extra complexity for nothing. We will also lose from it because pm_genpd_summary won't show you a per-device info.
domain status children performance /device runtime status
heg on 1000000 /devices/soc0/50000000.host1x active 1000000 /devices/soc0/50000000.host1x/54140000.gr2d suspended 0 mpe off-0 0 vdec off-0 0 /devices/soc0/6001a000.vde suspended 0 venc off-0 0 3d1 off-0 0 /devices/genpd:1:54180000.gr3d suspended 0 3d0 off-0 0 /devices/genpd:0:54180000.gr3d suspended 0 core-domain on 1000000 3d0, 3d1, venc, vdec, mpe, heg /devices/soc0/7d000000.usb active 1000000 /devices/soc0/78000400.mmc active 950000 /devices/soc0/7000f400.memory-controller unsupported 1000000 /devices/soc0/7000a000.pwm active 1000000 /devices/soc0/60006000.clock/tegra_clk_pll_c active 1000000 /devices/soc0/60006000.clock/tegra_clk_pll_e suspended 0 /devices/soc0/60006000.clock/tegra_clk_pll_m active 1000000 /devices/soc0/60006000.clock/tegra_clk_sclk active 1000000
I suppose if there's really no good way of doing this other than providing a struct device, then so be it. I think the cleaned up sysfs shown in the summary above looks much better than what the original would've looked like.
Perhaps an additional tweak to that would be to not create platform devices. Instead, just create struct device. Those really have everything you need (.of_node, and can be used with RPM and GENPD). As I mentioned earlier, platform device implies a CPU-memory-mapped bus, which this clearly isn't. It's kind of a separate "bus" if you want, so just using struct device directly seems more appropriate.
Just a heads up. If you don't use a platform device or have a driver associated with it for probing, you need to manage the attachment to genpd yourself. That means calling one of the dev_pm_domain_attach*() APIs, but that's perfectly fine, ofcourse.
We did something similar for XUSB pads, see drivers/phy/tegra/xusb.[ch] for an example of how that was done. I think you can do something similar here.
Thierry
Kind regards Uffe