mail archive of the barebox mailing list
 help / color / mirror / Atom feed
From: "Stefan Riedmüller" <s.riedmueller@phytec.de>
To: barebox@lists.infradead.org
Subject: Re: [PATCH] ARM: dts: imx6qdl: phycore: Remove emmc vmmc-supply
Date: Thu, 5 Dec 2019 14:08:16 +0100	[thread overview]
Message-ID: <b75f1cd1-7f49-007e-11f6-80544d729fe4@phytec.de> (raw)
In-Reply-To: <67c1cd67-9156-9e43-2be4-b3502877d95f@pengutronix.de>

Hi,

On 05.12.19 09:37, Ahmad Fatoum wrote:
> Hello,
> 
> On 12/5/19 9:07 AM, Sascha Hauer wrote:
>> On Tue, Dec 03, 2019 at 02:48:41PM +0100, Stefan Riedmueller wrote:
>>> There is no driver for the eMMC's vmmc-supply regulator in the barebox.
>>> Use a dummy regulator instead by simply deleting the vmmc-supply
>>> property.
>>>
>>> Signed-off-by: Stefan Riedmueller <s.riedmueller@phytec.de>
>>> ---
>>>   arch/arm/dts/imx6qdl-phytec-phycore-som.dtsi | 1 +
>>>   1 file changed, 1 insertion(+)
>>>
>>> diff --git a/arch/arm/dts/imx6qdl-phytec-phycore-som.dtsi b/arch/arm/dts/imx6qdl-phytec-phycore-som.dtsi
>>> index 69f252b42382..974e271f453d 100644
>>> --- a/arch/arm/dts/imx6qdl-phytec-phycore-som.dtsi
>>> +++ b/arch/arm/dts/imx6qdl-phytec-phycore-som.dtsi
>>> @@ -112,6 +112,7 @@
>>>   };
>>>   
>>>   &usdhc4 {
>>> +	/delete-property/ vmmc-supply;
>>
>> I don't like this approach very much. It's fine for barebox, but leads
>> to problems once you start Linux with the barebox device tree. I'd
>> rather go with the unmodified device trees (apart from the things
>> barebox changes to the device trees in order to start Linux).
> 
> How about a barebox,regulator-always-on property? If the regulator is unnecessary,
> it basically means you can assume it's always on when barebox runs.
> 
> If regulator_get is called with a property that points to such a node, a dummy
> regulator is returned with which enable is a no-op. Additionally, do the same
> for regulator-always-on, so the in-barebox device tree only needs to mark
> non regulator-always-on that are expected to be always on when it runs due to
> strapping/fuses as barebox,regulator-always-on.

What about regulators that are marked as regulator-always-on but need 
voltage adjustments? Or isn't this a real use case for the bootloader?

Regards,
Stefan

> 
> Thoughts?
> Ahmad
> 

_______________________________________________
barebox mailing list
barebox@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/barebox

  reply	other threads:[~2019-12-05 13:08 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-12-03 13:48 Stefan Riedmueller
2019-12-05  8:07 ` Sascha Hauer
2019-12-05  8:37   ` Ahmad Fatoum
2019-12-05 13:08     ` Stefan Riedmüller [this message]
2019-12-05 13:31       ` Ahmad Fatoum
2019-12-06 14:23         ` Sascha Hauer

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=b75f1cd1-7f49-007e-11f6-80544d729fe4@phytec.de \
    --to=s.riedmueller@phytec.de \
    --cc=barebox@lists.infradead.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox