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Compared to > implementing .get_state() I don't feel confident to do that without > testing though. (Though I could make the driver return an error code if > the register setting doesn't match.) >=20 > > If only .apply() uses it, then it's mostly fine, I suppose, because we > > don't care what the current (or initial) state is/was. So we either > > don't use the device or we overwrite it with a custom set of values. >=20 > I don't agree here. If the TEGRA_PWM_DEPTH setting is different in > hardware than the driver assumes, I'd say .apply() being wrong is worse > than .get_state() being wrong. So I'd either go with .get_state() as it > is now, or rely on someone with hardware to correct the depth setting > first. >=20 > Best regards > Uwe My state of mind when posting the Tegra264 support series was that the=20 driver -- for the time being -- intentionally relies on the DEPTH=20 register being at reset value. As such I think it's fine to rely on that=20 everywhere for now. Once we add support for setting the register at=20 runtime, I think it makes sense to update all code paths at that time. (Of course, I had intended to follow up with those patches sooner, but=20 ..) Mikko