On Wed, Oct 4, 2017 at 5:01 PM, Sudeep Holla <sudeep.holla@xxxxxxx> wrote: >>> + >>> +static struct platform_driver scmi_cpufreq_platdrv = { >>> + .driver = { >>> + .name = "scmi-cpufreq", >>> + }, >>> + .probe = scmi_cpufreq_probe, >>> + .remove = scmi_cpufreq_remove, >>> +}; >> >> You appear to have split this driver into the 'cpufreq' side and >> the 'protocol' handler in a different file. I already commented that >> the way the main scmi driver knows about all the protocols looks >> bad, here we can see another aspect of the same problem. >> >> Rather than manually register a platform_device for the purpose >> of connecting it to the cpufreq driver, there should be a way >> to dynamically register the protocol from the cpufreq driver >> and then have both in the same file. >> > > I agree that should be possible. I took this approach for 2 reasons: > > 1. to avoid all sorts of probe ordering issues > 2. we may have system with multiple instances of SCMI. E.g. a system > may have multiple remote processors, each controlling dvfs/power mgmt > of a subset of CPUs/devices controller in OS. > > I have to admit that I haven't thought too much in details yet. That's > the main idea behind scmi_handle and restricting access to that only to > sub-nodes in it. I am open to suggestions. How about introducing a separate bus_type for protocols? The platform_device you use here isn't really the best abstraction, and with a new bus_type, you can handle multiple instances of scmi as well as decoupling them from the protocol drivers. Arnd -- 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