From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 668882FFF89; Mon, 7 Sep 2026 18:04:26 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788804267; cv=none; b=mdpS3Pt8l1PNUYBnfy5/vhpNixzgdu+MznkxZTtM/W+W7Lz19SOKE54vE+FRGYLQ1skaPh6OMamvmuyi+LCWOsN7csSzH+c1KniwGKzmrjdML29LVWlfWG0CIIrHtMN2ErobIPV90Xh17Tl7ASF2Lu7zjYkwk4RIrvabu3an4Zk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788804267; c=relaxed/simple; bh=FJ3KlRxpUXOaqZYlnv1OpZKQEVhij59iEgNdlEfcslM=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=gAYU4QgXdyH0y0Od6bFNCRvZCUm57oxciZbPwV0+SRBtUsL6GLUjDO+NUuQiP0s3wQBft4mAAPYhP+phzjOgp1nOCguUEv+YFYUUYWJ06IXa4Pb2x0rIfyXb2wt9xTefh1eW/rwy5IeSvPtlzz+FUXCnFz/TuGVsLYytp+SNx+0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=c5ZH6r7B; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="c5ZH6r7B" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 25C751F00A3A; Mon, 7 Sep 2026 18:04:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1788804266; bh=uCwW6+gT3njRjgvc+5t1hsycs1+h5TBUJkyDrYO4u7I=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=c5ZH6r7B9rcNWDmwK9ka7TzCln2oQankfFX/ykdQqIr9OL4RsaS1rGTS10rbX5FUV 7eBtFIsfa6mn6hgb6QDwA7cxiRV0jDjSftOAswhbMhTzz7T+M3XFCm8lRQQClHJQsV /kLuTFZ/dOk7R6RGjnmBporPHmA+vqcs1RkKQ7OQrMjGIZO+3/p3fvAljfcstiuqVG 7jJMoq0nQafjd/0JCqJBtc0RDMACVvz4BBYsC0jib9Fec7EGhevjgcfIHbWh6DAUXQ 0exSOg4sVmKLum9eI7Jf1MAd3CP7iI2V8Deu+PJ4klKuNCsDaX4Eld8cd+brsXJ3My 6Yt7pRwj6bkTQ== Date: Mon, 7 Sep 2026 19:04:21 +0100 From: Conor Dooley To: Mark Brown Cc: Shashank Maurya , Liam Girdwood , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Florian Fainelli , Broadcom internal kernel review list , Marek Vasut , linux-kernel@vger.kernel.org, devicetree@vger.kernel.org, linux-rpi-kernel@lists.infradead.org, linux-arm-kernel@lists.infradead.org, venkata.valluru@oss.qualcomm.com, Jessica Zhang Subject: Re: [PATCH v2 2/2] regulator: rpi-panel-v2: Add required vcc-supply support Message-ID: <20260907-showroom-elevation-ba1a0792b7f7@spud> References: <20260907-rpi_reg-v2-0-0c59aa60d31f@oss.qualcomm.com> <20260907-rpi_reg-v2-2-0c59aa60d31f@oss.qualcomm.com> <20260907-ensnare-wanted-e86eeaf770b0@spud> <27fb1c11-c1eb-4494-ac38-d794baf80814@sirena.org.uk> Precedence: bulk X-Mailing-List: devicetree@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="FBwSaQHk5R1QIosT" Content-Disposition: inline In-Reply-To: <27fb1c11-c1eb-4494-ac38-d794baf80814@sirena.org.uk> --FBwSaQHk5R1QIosT Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Mon, Sep 07, 2026 at 06:09:57PM +0100, Mark Brown wrote: > On Mon, Sep 07, 2026 at 06:06:24PM +0100, Conor Dooley wrote: > > On Mon, Sep 07, 2026 at 11:16:08AM +0530, Shashank Maurya wrote: >=20 > > > + vcc =3D devm_regulator_get(&i2c->dev, "vcc"); > > > + if (IS_ERR(vcc)) > > > + return dev_err_probe(&i2c->dev, PTR_ERR(vcc), > > > + "Failed to get vcc supply\n"); >=20 > > This needs to be optional, because without it you'll break existing > > devicetrees. Unless you can explain how all existing users are > > nonfunctional (e.g. nothing ever enabled the supply, which seems > > doubtful given this surely worked when it was added) this must remain > > optional. >=20 > The core will stub in a dummy regulator for mandatory supplies that > don't have anything mapped by firmware, otherwise essentially all > regualtors would be optional and our error handling would be a disaster > zone. I always forget how this works. Thanks for the reminder. --FBwSaQHk5R1QIosT Content-Type: application/pgp-signature; name=signature.asc -----BEGIN PGP SIGNATURE----- iHUEABYKAB0WIQRh246EGq/8RLhDjO14tDGHoIJi0gUCap78pQAKCRB4tDGHoIJi 0uTBAP9evMaKmff7rJAlkiT1L5Zx4532B5L6cpV0O5jW49THDQEAx/4ZV4Z/icen QJ8YGia+cNCbCHFaHC2DFjOWUQ9irgA= =QAjk -----END PGP SIGNATURE----- --FBwSaQHk5R1QIosT--