Re: Regulator supplies when using Device Tree

From: Michael Bohan
Date: Thu Mar 29 2012 - 21:18:46 EST


On 3/29/2012 4:11 AM, Mark Brown wrote:
On Wed, Mar 28, 2012 at 05:06:48PM -0700, Michael Bohan wrote:

Are you aware of any other examples of submitted drivers with Device
Tree support that implement regulator devices that optionally have
an upstream supply? I looked at your tree recently and couldn't see
any such cases.

No, pretty much any drivers which optionally have an upstream supply
would be buggy and should therefore run into trouble during review.

Can you please elaborate on why this is a bad design? We have always used this model in the past, and the regulator framework is happy to support it.

We have identical hardware blocks that can be positioned to take a supply or not. So are you proposing we copy / paste our driver so that in one case rdesc->supply_name is NULL and the other case a valid supply name? I'm guessing you aren't implying this, but what alternatives do you suggest to support such a model?

In the thread mentioned by Rajendra, part of the motivation for putting the supply_name in the driver struct was 'no code changes in the individual drivers'. But that's exactly what we have here.

http://www.spinics.net/lists/linux-omap/msg58673.html

I was hoping that we could continue to treat regulator supplies as normal supplies, but somehow allow the framework to determine whether a regulator supply exists or not in the Device Tree configuration so the driver doesn't have to.

Thanks,
Mike

--
Sent by an employee of the Qualcomm Innovation Center, Inc.
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum.
--
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/