Devicetree
 help / color / mirror / Atom feed
From: Krzysztof Kozlowski <krzk@kernel.org>
To: Jorijn van der Graaf <jorijnvdgraaf@catcrafts.net>
Cc: David Heidelberg <david@ixit.cz>,
	 Krzysztof Kozlowski <krzk+dt@kernel.org>,
	Andrew Lunn <andrew+netdev@lunn.ch>,
	 Bjorn Andersson <andersson@kernel.org>,
	Conor Dooley <conor+dt@kernel.org>,
	 Conor Dooley <conor.dooley@microchip.com>,
	"David S . Miller" <davem@davemloft.net>,
	 Eric Dumazet <edumazet@google.com>,
	Jakub Kicinski <kuba@kernel.org>,
	 Konrad Dybcio <konradybcio@kernel.org>,
	Konrad Dybcio <konrad.dybcio@oss.qualcomm.com>,
	 Paolo Abeni <pabeni@redhat.com>, Rob Herring <robh@kernel.org>,
	 Luca Weiss <luca.weiss@fairphone.com>,
	devicetree@vger.kernel.org, linux-arm-msm@vger.kernel.org,
	 linux-kernel@vger.kernel.org, netdev@vger.kernel.org,
	oe-linux-nfc@lists.linux.dev
Subject: Re: [PATCH v4 4/6] nfc: s3fwrn5: enable the PVDD supply
Date: Tue, 11 Aug 2026 09:47:07 +0200	[thread overview]
Message-ID: <20260811-simple-impetuous-caribou-1f8596@quoll> (raw)
In-Reply-To: <20260807021001.239389-5-jorijnvdgraaf@catcrafts.net>

On Fri, Aug 07, 2026 at 04:09:59AM +0200, Jorijn van der Graaf wrote:
> The controller is powered by an externally switched PVDD rail. Get and
> enable it in the i2c phy probe, before any of the chip's pins is driven
> or its clock started, so the chip's power does not depend on whatever
> state the bootloader or platform left the rail in. Boards that do not
> describe the supply resolve to a dummy regulator, so the existing users
> keep working; they gain the regulator core's dummy-supply warning until
> their DTs describe the rail.

Last sentence is redundant - we know how regulator framework works.

What is not redundant and missing is why UART variants do not need
supply.

Best regards,
Krzysztof


  parent reply	other threads:[~2026-08-11  7:47 UTC|newest]

Thread overview: 15+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-08-07  2:09 [PATCH v4 0/6] nfc: s3fwrn5: support the S3NRN4V variant Jorijn van der Graaf
2026-08-07  2:09 ` [PATCH v4 1/6] nfc: s3fwrn5: drop of_match_ptr() from the I2C driver Jorijn van der Graaf
2026-08-11  7:43   ` Krzysztof Kozlowski
2026-08-07  2:09 ` [PATCH v4 2/6] nfc: s3fwrn5: use the "s3fwrn5_i2c" string literal directly Jorijn van der Graaf
2026-08-08  2:24   ` sashiko-bot
2026-08-07  2:09 ` [PATCH v4 3/6] dt-bindings: net: nfc: samsung,s3fwrn5: add the S3NRN4V Jorijn van der Graaf
2026-08-11  7:41   ` Krzysztof Kozlowski
2026-08-07  2:09 ` [PATCH v4 4/6] nfc: s3fwrn5: enable the PVDD supply Jorijn van der Graaf
2026-08-08  2:24   ` sashiko-bot
2026-08-11  7:47   ` Krzysztof Kozlowski [this message]
2026-08-07  2:10 ` [PATCH v4 5/6] nfc: s3fwrn5: support the S3NRN4V variant Jorijn van der Graaf
2026-08-08  2:24   ` sashiko-bot
2026-08-11  7:53   ` Krzysztof Kozlowski
2026-08-07  2:10 ` [PATCH v4 6/6] arm64: dts: qcom: milos-fairphone-fp6: Add NFC Jorijn van der Graaf
2026-08-08  2:24   ` sashiko-bot

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=20260811-simple-impetuous-caribou-1f8596@quoll \
    --to=krzk@kernel.org \
    --cc=andersson@kernel.org \
    --cc=andrew+netdev@lunn.ch \
    --cc=conor+dt@kernel.org \
    --cc=conor.dooley@microchip.com \
    --cc=davem@davemloft.net \
    --cc=david@ixit.cz \
    --cc=devicetree@vger.kernel.org \
    --cc=edumazet@google.com \
    --cc=jorijnvdgraaf@catcrafts.net \
    --cc=konrad.dybcio@oss.qualcomm.com \
    --cc=konradybcio@kernel.org \
    --cc=krzk+dt@kernel.org \
    --cc=kuba@kernel.org \
    --cc=linux-arm-msm@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=luca.weiss@fairphone.com \
    --cc=netdev@vger.kernel.org \
    --cc=oe-linux-nfc@lists.linux.dev \
    --cc=pabeni@redhat.com \
    --cc=robh@kernel.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