From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 096B05DF27; Wed, 6 Mar 2024 14:14:18 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1709734459; cv=none; b=pNeZzAk7ABAV7Ax4RBE13nnM5GvHiE5K3IeBN4uh4Hl0MvtvE3VnHSkrgo06DNTd9Qskffob/tYYczksxAjZ1dbXWMgeyfn3LrhiolvX6a4o0BjbO+AkMsGUgA25j/QcaFBXIah2fp562njdyBaM8OJhI8R1An5Yz02PXCIygAA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1709734459; c=relaxed/simple; bh=WIKTu97/GHeWLs/loOTdSuwxaW/iFGLGrqJns6l2xVE=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=q+kxCUK5cJ2tuqrSbLqW7Qgzy0YzBdP7yDrKNk1NXi187mO8PhO4tLvWbgwn9D3Q2PLJ6F1/zS3fvyxiS1FzFRPDzP//i+N78bVZdYUmE/RBilDracUm7inUoUOgR7UhYRh0xF9KzzvLmDUphkBPcvpPaZt9wbLPr93hAA6w1rw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=qLLpJbRa; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="qLLpJbRa" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 42A43C433C7; Wed, 6 Mar 2024 14:14:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1709734458; bh=WIKTu97/GHeWLs/loOTdSuwxaW/iFGLGrqJns6l2xVE=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=qLLpJbRabgifZKGJMJ6fgLVSinxL0cRS4XMQ7vZ1Hm2Z4OpQRIC5qFTc5MVKXSaqS Mv1uICGzG390Tzd3yZKlKBBZG/hKfBUsbOgC3YDlMv6dHBL1ijjCIJ+lK7uyPiderP 9HTXFFLj42HOhFd4NBOI86XfzNQ65xG2a4dGUI/mVrOpt6WI0nb23fQQiZLcwGJZ0f b6XpMRPudLmt9pXFItgYH9wRBjPlrFmckdGMc1QoxxFnR4GIQ5/hdWFlm3VxT2C+0K VVdYFWsqp3aN88cJaFEagcSLmprnMPgei7mvYlFk+vlhhMDWbcCmLB33yp7R1WTu92 tBEmsNZ/+mrPQ== Date: Wed, 6 Mar 2024 15:14:15 +0100 From: Maxime Ripard To: Sebastian Wick Cc: Maarten Lankhorst , Thomas Zimmermann , David Airlie , Daniel Vetter , Jonathan Corbet , dri-devel@lists.freedesktop.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] drm: Document requirements for driver-specific KMS props in new drivers Message-ID: <20240306-hulking-funky-fox-b9581b@houat> References: <20240229202833.198691-1-sebastian.wick@redhat.com> Precedence: bulk X-Mailing-List: linux-doc@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="jx5njdxurrf2cgix" Content-Disposition: inline In-Reply-To: <20240229202833.198691-1-sebastian.wick@redhat.com> --jx5njdxurrf2cgix Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable Hi, On Thu, Feb 29, 2024 at 09:28:31PM +0100, Sebastian Wick wrote: > When extending support for a driver-specific KMS property to additional > drivers, we should apply all the requirements for new properties and > make sure the semantics are the same and documented. >=20 > Signed-off-by: Sebastian Wick > --- > Documentation/gpu/drm-kms.rst | 5 +++++ > 1 file changed, 5 insertions(+) >=20 > diff --git a/Documentation/gpu/drm-kms.rst b/Documentation/gpu/drm-kms.rst > index 13d3627d8bc0..afa10a28035f 100644 > --- a/Documentation/gpu/drm-kms.rst > +++ b/Documentation/gpu/drm-kms.rst > @@ -496,6 +496,11 @@ addition to the one mentioned above: > =20 > * An IGT test must be submitted where reasonable. > =20 > +For historical reasons, non-standard, driver-specific properties exist. = If a KMS > +driver wants to add support for one of those properties, the requirement= s for > +new properties apply where possible. Additionally, the documented behavi= or must > +match the de facto semantics of the existing property to ensure compatib= ility. > + I'm conflicted about this one, really. On one hand, yeah, it's definitely reasonable and something we would want on the long run. But on the other hand, a driver getting its technical debt worked on for free by anyone but its developpers doesn't seem fair to me. Also, I assume this is in reaction to the discussion we had on the Broadcast RGB property. We used in vc4 precisely because there was some userspace code to deal with it and we could just reuse it, and it was documented. So the requirements were met already. Maxime --jx5njdxurrf2cgix Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iHUEABYKAB0WIQRcEzekXsqa64kGDp7j7w1vZxhRxQUCZeh6NgAKCRDj7w1vZxhR xduLAQDWHzR22qPgjQfjobO9zEFwx3q0Cfg112/Dqo7VmDn4DQEAoshXfdwKoAl4 /YStjp8eyrAPpOr5jgxK6Xqh7WXF6gM= =Z2rn -----END PGP SIGNATURE----- --jx5njdxurrf2cgix--