Hi Sakari, Thanks for your feedback. On 2018-04-04 23:13:57 +0300, Sakari Ailus wrote: [snip] > > > + pm_runtime_enable(&pdev->dev); > > > > Is CONFIG_PM mandatory on Renesas SoCs? If not, you end up with the > > device uninitialised at probe, and pm_runtime_get_sync will not > > initialise it either if CONFIG_PM is not enabled. I guess you could > > call your runtime_resume function unconditionally, and mark the device > > as active in runtime_pm using pm_runtime_set_active. > > There doesn't seem to be any runtime_resume function. Was there supposed > to be one? No there is not suppose to be one. > > Assuming runtime PM would actually do something here, you might add > pm_runtime_idle() to power the device off after probing. > > I guess pm_runtime_set_active() should precede pm_runtime_enable(). The CSI-2 is in the always on power domain so the calls to pm_runtime_get_sync() and pm_runtime_put() are there in the s_stream() callback to enable and disable the module clock. I'm no expert on PM but in my testing the pm_ calls in this driver seems to be correct. 1. In probe I call pm_runtime_enable(). And rudimentary tests shows the clock is off (but I might miss something) as I wish it to be until stream on time. 2. In s_stream() I call pm_runtime_get_sync() before writing any register when starting a stream. And likewise I call pm_runtime_put() when stopping and I no longer need to write to a register. 3. In remove() I call pm_runtime_disable(). Am I missing something obvious here? -- Regards, Niklas Söderlund
