From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from relay1-d.mail.gandi.net (relay1-d.mail.gandi.net [217.70.183.193]) (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 6D3FE1D5CF2; Mon, 9 Jun 2025 09:07:30 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.70.183.193 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1749460052; cv=none; b=ng6PQgvKoy/6FcgmX0n7kqC6YA2ntKymGonTYzLfhJtSKAyjWbwG/EghDTQNbpHJx8xuTwqgPsy03+zuMgGDKtuy+yj2HoPj9BmEnPaGzhbX4XCsVGwX3b1ujBnjbrBXQygHCntCxuCmatr2oqg0oyK4ixneH8w36l/Y+8yq5ko= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1749460052; c=relaxed/simple; bh=erCWTv1iBu+zhino5X8lqV0NnPCfncKslxTm/LttBO4=; h=From:To:Cc:Subject:In-Reply-To:References:Date:Message-ID: MIME-Version:Content-Type; b=b/AWWINMStwszDojSMLrwb6N2dn3zKnW6Bw0tiGq43HCnC0NOOLXDWNo0kXJDcwAuiTP1w2uzhgldSDEG81c1bC8w43opADlHEtai0F2mv/FFiLfez2mep6tJlQFZH6XzY7BYlevOQ8r4VWHoKGwqes4lN+7E//xU9CsNIBYXZY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=bootlin.com; spf=pass smtp.mailfrom=bootlin.com; dkim=pass (2048-bit key) header.d=bootlin.com header.i=@bootlin.com header.b=mqb8fdfU; arc=none smtp.client-ip=217.70.183.193 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=bootlin.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=bootlin.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=bootlin.com header.i=@bootlin.com header.b="mqb8fdfU" Received: by mail.gandi.net (Postfix) with ESMTPSA id A8E3B4326B; Mon, 9 Jun 2025 09:07:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bootlin.com; s=gm1; t=1749460048; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=erCWTv1iBu+zhino5X8lqV0NnPCfncKslxTm/LttBO4=; b=mqb8fdfUAPmh1nGlznkXqcy65DTSqmBNVTK2jEWW+sZy/L4Mwn72e1BDiJ6cNad6U5dhco u2tGJQquy5bw3+kHVVdCbRKfHfSnzViq+cQDLYETVOvMuFONiHdKYsOexHM9Wtq5TlUA27 Wq6EQAHizzOUgD/5vnR/JKaEAE9T6g0f+lVPjJLQmVUJ7c33S2FZ74WRNQJywTAYKrGQVk fSKxOTK0HsojuD7X2IAULVVy80JhHB4I6IhrxTD2EO/Jy5eiufVse+maoLpEn6h5EHezDB jnD8xN55kzjPhIwMon0UA42cRqfRK4brNShFTyzymTAVg6aNocx8YOUgeY/CTQ== From: Miquel Raynal To: Alexey Charkov Cc: Krzysztof Kozlowski , Rob Herring , Mark Brown , Krzysztof Kozlowski , Conor Dooley , Tudor Ambarus , Pratyush Yadav , Michael Walle , Richard Weinberger , Vignesh Raghavendra , linux-spi@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mtd@lists.infradead.org, linux-arm-kernel@lists.infradead.org Subject: Re: [PATCH 1/3] dt-bindings: spi: Add VIA/WonderMedia serial flash controller In-Reply-To: (Alexey Charkov's message of "Fri, 6 Jun 2025 13:06:22 +0400") References: <20250510-wmt-sflash-v1-0-02a1ac6adf12@gmail.com> <20250510-wmt-sflash-v1-1-02a1ac6adf12@gmail.com> <20250514204159.GA2988411-robh@kernel.org> <2b520ae5-eb0d-40eb-ba73-cc18759f33b9@kernel.org> User-Agent: mu4e 1.12.7; emacs 29.4 Date: Mon, 09 Jun 2025 11:07:27 +0200 Message-ID: <87y0u1z3jk.fsf@bootlin.com> 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=utf-8 Content-Transfer-Encoding: quoted-printable X-GND-State: clean X-GND-Score: -100 X-GND-Cause: gggruggvucftvghtrhhoucdtuddrgeeffedrtddugdeltdelucetufdoteggodetrfdotffvucfrrhhofhhilhgvmecuifetpfffkfdpucggtfgfnhhsuhgsshgtrhhisggvnecuuegrihhlohhuthemuceftddunecusecvtfgvtghiphhivghnthhsucdlqddutddtmdenucfjughrpefhvfevufgjfhgffffkgggtgfesthhqredttderjeenucfhrhhomhepofhiqhhuvghlucftrgihnhgrlhcuoehmihhquhgvlhdrrhgrhihnrghlsegsohhothhlihhnrdgtohhmqeenucggtffrrghtthgvrhhnpeffgefhjedtfeeigeduudekudejkedtiefhleelueeiueevheekvdeludehiedvfeenucfkphepledtrdekledrudeifedruddvjeenucevlhhushhtvghrufhiiigvpedtnecurfgrrhgrmhepihhnvghtpeeltddrkeelrdduieefrdduvdejpdhhvghloheplhhotggrlhhhohhsthdpmhgrihhlfhhrohhmpehmihhquhgvlhdrrhgrhihnrghlsegsohhothhlihhnrdgtohhmpdhnsggprhgtphhtthhopeduiedprhgtphhtthhopegrlhgthhgrrhhksehgmhgrihhlrdgtohhmpdhrtghpthhtohepkhhriihksehkvghrnhgvlhdrohhrghdprhgtphhtthhopehrohgshheskhgvrhhnvghlrdhorhhgpdhrtghpthhtohepsghrohhonhhivgeskhgvrhhnvghlrdhorhhgpdhrtghpthhtohepkhhriihkodgutheskhgvrhhnvghlrdhorhhgpdhrtghpthhtoheptghonhhorhdoughtsehkvghrnhgvlhdrohhrghdpr hgtphhtthhopehtuhguohhrrdgrmhgsrghruhhssehlihhnrghrohdrohhrghdprhgtphhtthhopehprhgrthihuhhshheskhgvrhhnvghlrdhorhhg X-GND-Sasl: miquel.raynal@bootlin.com Hi Alexey, >> > Happy to reference the spi-controller.yaml binding if so. >> >> SPI NOR flashes are still child devices of an SPI controller. You can >> look at other examples - aren't they all using spi-controller? Why this >> would be different? Unless you found some cases that are different, but >> then which ones? > > No strong opinions here, and no expectation of any special treatment > :) Just wanted to consult on what's most appropriate. > > My (subjective and perhaps unfounded) expectation when seeing > something advertise itself as an SPI controller was that it would be a > general purpose SPI master, to which one can e.g. connect an SPI > driven LCD screen and get it to work with generic Linux SPI > infrastructure - which would not be possible with this single-purpose > NOR-only flash controller. Given that I don't know how flexible or > restrictive other examples are in terms of driving arbitrary SPI > devices, I thought it's better to just ask. > > What I'm getting from this exchange here is that I'd better use the > spi-controller binding and respective node names regardless of the > fact that this controller cannot drive arbitrary SPI devices beyond > NOR flash (which, as I'm getting, is irrelevant after all). Just for information, there are several SPI controllers which are optimized for flash handling (not only NOR, though) and for that we have a spi-mem layer which allows to reference a set of SPI memory "only" callbacks. On the description side though, these controllers are like all other SPI controllers, so the same controller bindings may apply. Thanks, Miqu=C3=A8l