Re: [PATCH V3 2/4] regulator: tps62360: add dt support

From: Laxman Dewangan
Date: Sun May 20 2012 - 03:24:25 EST


On Saturday 12 May 2012 03:00 AM, Mark Brown wrote:
* PGP Signed by an unknown key

On Fri, May 11, 2012 at 09:05:01PM +0530, Laxman Dewangan wrote:

I think this is not require to enable always otherwise there may be
power dissipation from this path always, just when we off the rail
(disable rail or when go to shutdown so that the voltage output can
go down faster).
Should we add "unsigned en_discharge:1" in regulator init data but
did not get how core driver can use this flag specially when
shutdown?
Oh, now you say this I think I remember discussing this with you before!
This is pretty unusual for such hardware. Normally there's something in
the digital block so that the discharge is only enabled if the regulator
is disabled, if it's enabled then the discharge would automatically be
taken off since actively discharging while enabled doesn't make sense
and may in fact be actively harmful.


Just to share here with our new pmu which we got recently, the discharge path behavior is exactly same as what Mark mentioned
It need to be enable always. The pmu auto disable the DISC path in normal operation so there is no power dissipation but when it detects the en_bit is written 0 or any external control is making the rail to be off, it automatically turn on the path so that ramp-down can happen faster.
Just we need to enable this always.

If the hardware doesn't do that then I'd expect the driver to take care
of this if it implements the framework feature (once the framework
feature is added).

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