From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail11.truemail.it (mail11.truemail.it [217.194.8.81]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 2341B175A6B; Tue, 21 Apr 2026 08:38:48 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.194.8.81 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776760730; cv=none; b=l7P9SKxLMscM41iPkH9/BB2BkEYyP9AZICneLh+jcn7vkJXLBktR4SGR5p0QpACP3j56KFN7t6rYvq5neFL1+wngdFFcPUuTFArL1HY2ZBmzLgJdcxp0OWlZcp9YGxt9jy9G0Npb2cI4SCZagjgP6Ap7lQnYn9ph9JJFI8086C4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776760730; c=relaxed/simple; bh=jI+w1zBcEoCC3Gc9XybfVrRe2P3szNtki5Muta6764A=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=hR6z5fLe1sdWdO0RtbGahal/vIz1HbJUiJIkre4xbLxjMELA6xRULTrvjopZ5dnrDQ9+JyS+YSw7vUgkA7GcOYQsMff4SznoVtrH7Su3UJsI7jJtoUk1y1nG/6eG6x++H7G8QHr0sySiwSoQSGoORyYA1Vj/TJtmTs2ihNdqCog= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=dolcini.it; spf=pass smtp.mailfrom=dolcini.it; dkim=pass (2048-bit key) header.d=dolcini.it header.i=@dolcini.it header.b=wVB3NCGG; arc=none smtp.client-ip=217.194.8.81 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=dolcini.it Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=dolcini.it Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=dolcini.it header.i=@dolcini.it header.b="wVB3NCGG" Received: from francesco-nb (248.201.173.83.static.wline.lns.sme.cust.swisscom.ch [83.173.201.248]) by mail11.truemail.it (Postfix) with ESMTPA id DF2681FCCC; Tue, 21 Apr 2026 10:38:46 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=dolcini.it; s=default; t=1776760727; bh=fm/1RzOdzAzq+zYf9dVgGl/EQiJTiHbbxKKZTRaHaas=; h=From:To:Subject; b=wVB3NCGGdkDBXDDX0Caowe7B9NmNno6L37Hm0u4ijIg54Rz7yfQ7YNA9x3/yJQxC2 g2LmHZ374W3NXKqfCRZschcvbMScQ47of7ea1nq3ttprR9xLtwvXk/F6PY+3hgHhR+ pulcJTzCklCgEWc5XStBA075e3h3vYc6U8DQ0gD/PQw7Qjx9aknIFqHn7Tn88HiI9N iRWFIv88HOy8jjH11UdP2VlhEw+ziN0cx/2Xdx3yEnWQ7PUzQNPd7Y+NnWF5evHsnd C/GePhNDs4V7qEj3swuWG+rITOpNFeIobd/UFAJgDscX1oF656e5VLyKqeP1bgz8jl gCapIwrKLGlkw== Date: Tue, 21 Apr 2026 10:38:43 +0200 From: Francesco Dolcini To: Krzysztof Kozlowski Cc: Conor Dooley , Francesco Dolcini , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Mark Brown , Francesco Dolcini , devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-spi@vger.kernel.org Subject: Re: [PATCH v1 1/2] dt-bindings: trivial-devices: add toradex,lava-hat-spi Message-ID: <20260421083843.GA23508@francesco-nb> References: <20260420114537.78160-1-francesco@dolcini.it> <20260420114537.78160-2-francesco@dolcini.it> <20260420-task-navy-370ea247fe1d@spud> <005d96ea-b250-4af8-9c5b-d145bae892e5@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@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: <005d96ea-b250-4af8-9c5b-d145bae892e5@kernel.org> On Mon, Apr 20, 2026 at 06:10:08PM +0200, Krzysztof Kozlowski wrote: > On 20/04/2026 18:02, Conor Dooley wrote: > > On Mon, Apr 20, 2026 at 01:45:35PM +0200, Francesco Dolcini wrote: > >> From: Francesco Dolcini > >> > >> Add a compatible string for the SPI loopback device present on the > >> Toradex LAVA HAT test fixture. > >> > >> The Toradex LAVA HAT is a board used for automated hardware-in-the-loop > >> (HIL) testing, it provides several test-related functionalities, and > >> exists in multiple variants depending on the board it is mated with. The > >> SPI function is implemented with a loopback on the MISO/MOSI signals. > >> > >> As the device can be fully described using only "compatible" and "reg", > >> it is appropriate to list it under trivial-devices.yaml rather than > >> introducing a dedicated binding. > >> > >> The SPI implementation is identical across all Toradex LAVA HAT > >> variants, so a single compatible string is sufficient. > >> > >> Link: https://lore.kernel.org/all/20260310133254.GA51497@francesco-nb/ > >> Link: https://lore.kernel.org/all/20260316073547.11437-3-francesco@dolcini.it/ > >> Signed-off-by: Francesco Dolcini > > > > Acked-by: Conor Dooley > > pw-bot: not-applicable > > > Heh, let's wait. That's a test device, so it won't be ever used in any > final product, right? So not in final DTS? It will be used in various DT overlay, that I plan to send for inclusion in mainline Linux kernel once we have a way forward. So yes, there will be DTB files using it. The need is to be able to test SPI with a mainline Linux kernel, so I am looking for a solution that works in mainline Linux. What is the reason to not wanting to have a DT overlay file for a test device in the Linux kernel? I assume that I would not be able to have an overlay included, if it uses a compatible that is defined in incomplete-devices. This was my understanding from https://lore.kernel.org/all/a3796f8b-f94c-4d0d-a0b9-b2970e43e28d@kernel.org/ > Then why it's here? I think I directed previously to document it with > the rest of test devices - in incomplete-devices schema? Because, that would not allow to add it to any DT file, from my understanding. I linked here both the email thread in which we discussed the topic before, and I understood it was ok to send it, given we have an actual HW for it and we plan to submit DT to support it in mainline Linux. I see we are running in circle, apologize for that. What can I do so that we can move forward? Francesco