Re: Regulator enable/disable delay based on board design: How tohandle?

From: Laxman Dewangan
Date: Mon Feb 13 2012 - 12:59:53 EST


On Monday 13 February 2012 10:07 PM, Mark Brown wrote:
* PGP Signed by an unknown key

On Mon, Feb 13, 2012 at 02:48:18PM +0530, Laxman Dewangan wrote:

We observed that some of the rail enable/disable settling time
depends on the board design specially based on external capacitor
connected on
rails. This is observed mainly on VBUS regulator rail where
difference on the capacitance value which is connected on rail makes
the on/off
time to vary.
Usually this would be handled via regulator driver platform data as the
regulator will typically be designed with particular external components
in mind and (especially in the case of DCDC convertors) may need to be
configured differently depending on the choice of passive components.
Many regulators also have some software control for the ramp rate,
mainly intended to limit inrush currents on system startup, which can be
varied at runtime if desired.


Interesting, Many regulator driver is written like it just take the regulator_init_data as the platform data and does not leave any option to add any new platform parameters.
Not sure how can we add platform data without too much tempering on the existing user, but if we can add parameter of delay(settling time) in struct regulator_init_data then almost all driver can support such platform specific delay.

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