[PATCH v2 06/10] mmc: omap_hsmmc: add support for pbias configuration in dt
Laurent Pinchart
laurent.pinchart at ideasonboard.com
Fri Jun 14 00:53:55 EST 2013
Hi,
On Thursday 13 June 2013 20:22:42 Balaji T K wrote:
> On Thursday 13 June 2013 03:32 PM, Laurent Pinchart wrote:
> > On Thursday 13 June 2013 02:53:54 Tony Lindgren wrote:
> >> * Linus Walleij <linus.walleij at linaro.org> [130613 02:42]:
> >>> On Thu, Jun 6, 2013 at 9:14 PM, Balaji T K <balajitk at ti.com> wrote:
> >>>> PBIAS register configuration is based on the regulator voltage
> >>>> which supplies these pbias cells, sd i/o pads.
> >>>> With PBIAS register address and bit definitions different across
> >>>> omap[3,4,5], Simplify PBIAS configuration under three different
> >>>> regulator voltage levels - O V, 1.8 V, 3 V. Corresponding pinctrl
> >>>> states
> >>>> are defined as pbias_off, pbias_1v8, pbias_3v.
> >>>>
> >>>> pinctrl state mmc_init is used for configuring speed mode, loopback
> >>>> clock (in devconf0/devconf1/prog_io1 register for omap3) and pull
> >>>> strength configuration (in control_mmc1 for omap4)
> >>>>
> >>>> Signed-off-by: Balaji T K <balajitk at ti.com>
> >>>
> >>> You *need* Lee Jones and Mark Brown to review this.
> >>> Maybe Laurent has something to add too.
> >>>
> >>> Ux500 had the very same thing, and there this was solved using
> >>> a GPIO regulator for "vqmmc" a level-shifter. I vaguely remember
> >>> Laurent doing something similar with the SH stuff.
> >
> > The SH pinctrl driver registers an MMC regulator. The code is available at
> > git://git.kernel.org/pub/scm/linux/kernel/git/horms/renesas.git. Look at
> > drivers/pinctrl/sh-pfc/pfc-sh73a0.c in tags/renesas-next-20130611v2.
>
> Thanks for the link, I think I need some time to understand
> where pfc->window[1].virt is coming from.
That's just the ioremapped pinctrl device address spaced.
--
Regards,
Laurent Pinchart
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