Re: [PATCH v2] mmc: Add support for JMicron 388 SD/MMC controller

[Takashi Iwai <tiwai@suse.de>]

At Wed, 8 Dec 2010 21:18:38 -0500,
zhangfei gao wrote:
> 
> On Wed, Dec 8, 2010 at 4:04 AM, Takashi Iwai <tiwai@suse.de> wrote:
> > JMicron 388 SD/MMC combo controller supports the 1.8V low-voltage for
> > SD, but MMC doesn't work with the low-voltage, resulting in an error
> > at probing.
> >
> > This patch adds the support for multiple voltage mask per device type,
> > so that SD works with 1.8V while MMC forces 3.3V.  Here new ocr_avail_*
> > fields for each device are introduced, so that the actual OCR mask is
> > switched dynamically.
> 
> It is great that you also have 1.8v requirement, could you help share some info?
> What's the card you are using, mmc or sd, if sd, does cmd11 is required?
> Which component will provide voltage in your platform, external pmic
> or controller?
> What's the init voltage, 3.3v? and then switch to 1.8v, does some time
> required to wait voltage to be stable?

I guess Aries can answer to these at best :)
1.8V case was tested mainly by him.


thanks,

Takashi