[PATCH 4/4] sdhci-s3c: add regulator support

Mark Brown broonie at opensource.wolfsonmicro.com
Wed Jul 28 13:14:20 EDT 2010

On Wed, Jul 28, 2010 at 07:06:22PM +0200, Maurus Cuelenaere wrote:
>  Op 28-07-10 17:41, Mark Brown schreef:

> >>> +	if (sc->vmmc) {
> >>> +		int ret = regulator_disable(sc->vmmc);
> >>> +		if (ret)
> >>> +			return ret;
> >>> +		mdelay(2);

> >> Shouldn't these delays be handled in the regulator framework itself?

> > A 2ms delay on power down seems suspicious for a regulator. I'm not
> > sure why this is required but if it is I suspect it's due to a large
> > cap on the regulator output and light load rather than something
> > that's always true for whatever regulator is providing the supply.

> I wasn't suggesting to do the delay in the framework *itself*, rather in the
> regulator driver and/or the board platform code which needs this delay.

It's unlikely to be a property of the regulator in general, it sounds
like it's a property of the MMC application somehow (most likely due to
very light loading).  Possibly it should be platform configurable, but I
suspect in the MMC driver.

It'd be nice to know exactly what the delay is for...

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