Messages in this thread | | | From | "Kim, Milo" <> | Subject | RE: [PATCH 1/2] regulator: support operating mode in the device tree structure | Date | Tue, 7 May 2013 23:46:12 +0000 |
| |
> -----Original Message----- > From: Mark Brown [mailto:broonie@kernel.org] > Sent: Wednesday, May 08, 2013 1:05 AM > To: Kim, Milo > Cc: Liam Girdwood; linux-kernel@vger.kernel.org > Subject: Re: [PATCH 1/2] regulator: support operating mode in the > device tree structure > > On Tue, May 07, 2013 at 01:09:14PM +0000, Kim, Milo wrote: > > For better power efficiency, regulator subsystem provides operating > mode. > > (fast, normal, idle and standby) > > The operating mode is selective by a regulator consumer. > > > > With this patch, regulator operating mode can be set in the DT > structure. > > If any operating mode is configured, then 'valid_ops_mask' should be > set with > > REGULATOR_CHANGE_MODE. > > It's not clear to me that these modes are a useful thing to be exposing > in device tree - they've always been rather arbatrary and are becoming > less and less relevant as regulator hardware improves in its ability to > adapt to load. I think for fixed modes that don't vary dynamically at > runtime the best thing is just to make the modes custom so they map > onto > the device datasheets clearly. That seems to be most of the usage > anyway.
I agree the operating mode depends on the device.
It's my intention to guarantee same operations in the DT as the regulator constraints in the platform side. In case a regulator has specific 'valid_modes_mask', the operating mode is unable to be set with the device tree. For some regulator drivers such as LP8720/5 and LP8788, this patch would be useful because there is no difference between configuration in the platform side and the device tree.
Thanks, Milo
| |