Re: [PATCH v2 1/4] ARM: dts: omap4-panda: Add USB Host support
From: Benoit Cousson
Date: Wed Jun 19 2013 - 08:35:35 EST
Hi Tony,
On 06/19/2013 07:27 AM, Tony Lindgren wrote:
* Benoit Cousson <b-cousson@xxxxxx> [130619 03:17]:
On 06/19/2013 02:46 AM, Tony Lindgren wrote:
We have a similar issue with the MMC1 PBIAS. I think in the long run we
should expand regulator (and possibly pinctrl) framework(s) to handle
comparators. We could just assume that a comparatator is a regulator,
and have a comparator binding that just uses the regulator code.
In the case of pbias, the pinctrl seems to be a much better fit for
my point of view. pinctrl can handle pin configuration and this is
what the pbias is in the case of MMC pins.
Well just recently Linus W specifically wanted us to use regulator
framework for the MMC1 PBIAS rather than pinctrl. That's because
from consumer driver point of view, it changes voltage and there's
a delay involved. So I guess no conclusion yet, and it's best to
do stand alone drivers to deal with those that use pinctrl for the
pinctrl specific parts and export it as a regulator for the consumer
devices.
In the case of pbias, the boundary is not that clear, and it is true
that writing a complete pinctrl driver is really overkill.
I've tried in the past, and gave up due to the complexity of fmwk and
the lack of time. I still think, it is a much better fmwk to handle pin
configuration than the regulator fmwk.
That's pretty much along the lines what Roger has done,
except the transceiver could use the pinctrl-single,bits for the
muxing and pinconf.
Well, in that case, this is a reset line, so it does not have anything
to do with voltage :-)
Anyway, thanks to Florian, we know that there is a real solution to that
problem. It is just not merged now :-(
Regards,
Benoit
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/