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 B3E9F48095A; Tue, 5 May 2026 15:40:12 +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=1777995612; cv=none; b=JnZGd462mkk+pWeftJFlnxyxOsdQH35+l4SJGPpHhDoiKLxl93qVz4Hs0mou1weeIPdrFylAaepjCKas8J1SEuIFbvWQrpP3vZSNZEfB1mOAPq2Ijwdd2IFY0YlxGwHyPiu3kBLzETfarn3DMEl1VnvXlCt3twg4Q7ycDFlBgGw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777995612; c=relaxed/simple; bh=R/Jj1MGKLOsi4YiefeZMpJJYAkiTt2dPqIT+kEApTfQ=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=ee6jqlUrnFKy28pkyz+y5b+Cy/WJLdAV+m0NulVxfeOq/wm5FamDxLy1SAy1X01nBwky8hQ3FSjEkk9tVC0peqHLs4kLTbx3GA2fQLvVe+1CYR2+Hzj4hScrF0kRq/Y3JoCETmVQbNARWqVsuUzZelf3NIb3x1EJS92imijOTyU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=NY6aSg9e; 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="NY6aSg9e" Received: by smtp.kernel.org (Postfix) with ESMTPSA id D69CDC4AF0D; Tue, 5 May 2026 15:40:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1777995612; bh=R/Jj1MGKLOsi4YiefeZMpJJYAkiTt2dPqIT+kEApTfQ=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=NY6aSg9eOACI7ankJJ6pgIgHu8rLwE01PNWcAWRF6A7SfKOIykqXoxooJrOaTsAaP OM9SjgizlQfU/WASj/62IPMd8AV9BXn0BMBlPTIbYE7v24Mef7holzCrKYsGyKcfkR jlMYhac5lfvboKwHs0YX/NhCx+SumsTfhRXxYC/KN0jAK8C/UaEH+Ow50iCt/vipi4 s9Kn/F1QiQKVTMgicGtfU3XFbOvzKblpdk9C4lc489yqPYp1ci4uKErc0LoTMrso0o djJWAhbxTrrnxf7GoTzbtWLXMR6Y4G7nFiRJtzRJ73kOrOWS5nYhVZjNuEvTAqIMPe IHwd2GLV7dzSg== Date: Tue, 5 May 2026 10:40:09 -0500 From: "Rob Herring (Arm)" To: Krzysztof Kozlowski Cc: Conor Dooley , devicetree@vger.kernel.org, Conor Dooley , linux-kernel@vger.kernel.org, Krzysztof Kozlowski Subject: Re: [PATCH v2] docs: dt: writing-bindings: Extend compatible fallbacks guideline Message-ID: <177799560843.2973367.1894381541645031550.robh@kernel.org> References: <20260427160739.175451-2-krzysztof.kozlowski@oss.qualcomm.com> Precedence: bulk X-Mailing-List: devicetree@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20260427160739.175451-2-krzysztof.kozlowski@oss.qualcomm.com> On Mon, 27 Apr 2026 18:07:40 +0200, Krzysztof Kozlowski wrote: > Extend the guidelines when to use fallback compatibles to cover to > common review responses. Devices are most likely compatible and should > use fallbacks when having: > > 1. Compatible programming interface, meaning one is a subset, and Linux > device drivers can use the subset to correctly match/bind and still > operate with the subset features. > > 2. Device variant discovery through some means, like registers. > > Devices are incompatible and fallback is not suitable when that > fallback cannot be used by the drivers to match/bind. In the same time > commit message should clearly explain when the code suggests devices > are compatible, but the binding does not define them as such. > > Acked-by: Conor Dooley > Signed-off-by: Krzysztof Kozlowski > > --- > > Changes in v2: > 1. Include Conor's suggestion about commit msg, a bit rephrased. > 2. Add tag > 3. Drop double-space, because file does not use that format (old habit). > --- > .../devicetree/bindings/writing-bindings.rst | 12 +++++++++++- > 1 file changed, 11 insertions(+), 1 deletion(-) > Applied, thanks!