From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mx.nabladev.com (mx.nabladev.com [178.251.229.89]) (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 4620740F756; Thu, 27 Aug 2026 17:00:56 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=178.251.229.89 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787850059; cv=none; b=OfTJ+EpwK5KDI3xjZTB3xa49XZ3mxzTsOEBaoOCKHc26nZb59pFzj9q4g16zioqUAalYeee2HuZv0A8a1vAYBmvgBL2gAbk/4P4X6paxqy8rdzpR6UjSEfRXTcibaSv940feFS/gi0cF3iw1bAhvjui2vr99fejeYL3EsGs54/E= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787850059; c=relaxed/simple; bh=aPn2iADZBp1ZnFzWq2/FeU2y85nOQ+T4Row0SiHHb94=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=U1mcUeJtsm6oriyrR9m80bkaUWu0vTrJUb7z53QgfRezHqxD6fVp9myiVQRQ0zSF0qV9WDd3MEiDgTNUDRBf0NomMbTmAfVyS4BhJ4swG1c+3hSx7NS+6jL+FloxJDtbenQhLuxO87p0CraFDzuxXN+up6DcpJKHt/SCnLMOSBM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=nabladev.com; spf=pass smtp.mailfrom=nabladev.com; dkim=pass (2048-bit key) header.d=nabladev.com header.i=@nabladev.com header.b=HfsCtKtM; arc=none smtp.client-ip=178.251.229.89 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=nabladev.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=nabladev.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=nabladev.com header.i=@nabladev.com header.b="HfsCtKtM" Received: from [127.0.0.1] (localhost [127.0.0.1]) by localhost (Mailerdaemon) with ESMTPSA id BD7BC11D05A; Thu, 27 Aug 2026 19:00:49 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=nabladev.com; s=dkim; t=1787850050; h=from:subject:date:message-id:to:cc:mime-version:content-type: content-transfer-encoding:content-language:in-reply-to:references; bh=rPYi6o+LeNrSB5Cku6LECS3A/JbV3lwzwlsRbFujYSo=; b=HfsCtKtM0Odc8d0h8jjGdiLRvEKuf8sfG7yZb9lnTrzyupAFYcU1dc1Pzb/+vIDE15WqbO pxiXWZ6FCZpO+JMf4T5PjsZDHKu4aqcE8e9/CBg5Jtf11RnwCZzDvYK58aKyMYqOYApRpC sSiAqz6PtVgCgJi+wB9iavc+FIpytkWJWw7TvjwpTuE3FHMnjp6JErsDm+WHske3gNQOw8 SQZZza2kErv4KfUUwPc2/0JO/syBicC0KHZZQcvrj0Dx4xSmhsNZz8B4BbvS2xUX+W5ZWt ByOsH+H1HqKDUT3jnjAMeZKVnHXN7c8L8Quacx/XM1YFys8jCgEODKYzN2QBgw== Message-ID: <9b197208-dbb4-44dd-b0c0-b4dcaa57c403@nabladev.com> Date: Thu, 27 Aug 2026 17:04:40 +0200 Precedence: bulk X-Mailing-List: linux-usb@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v3 7/9] dt-bindings: arm: stm32: Switch st,stm32mp23/25-syscfg into simple-mfd To: Krzysztof Kozlowski Cc: linux-usb@vger.kernel.org, fabrice.gasnier@foss.st.com, Alexandre Torgue , Christian Bruel , Conor Dooley , Greg Kroah-Hartman , Krzysztof Kozlowski , Maxime Coquelin , Neil Armstrong , Pankaj Dev , Rahul Kumar , Rob Herring , Rosen Penev , Thinh Nguyen , Vinod Koul , devicetree@vger.kernel.org, kernel@dh-electronics.com, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-phy@lists.infradead.org, linux-stm32@st-md-mailman.stormreply.com References: <20260822074816.548662-1-marex@nabladev.com> <20260822074816.548662-8-marex@nabladev.com> <20260827-skilled-optimal-shellfish-c548e5@quoll> Content-Language: en-US From: Marek Vasut In-Reply-To: <20260827-skilled-optimal-shellfish-c548e5@quoll> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Last-TLS-Session-Version: TLSv1.3 On 8/27/26 3:07 PM, Krzysztof Kozlowski wrote: > On Sat, Aug 22, 2026 at 09:46:40AM +0200, Marek Vasut wrote: >> The st,stm32mp23-syscfg and st,stm32mp25-syscfg can have subnodes, which >> represent the USB 2.0 FEMTO-PHY. Turn the syscfg into "simple-mfd" so the >> PHYs would get populated by the OS. > > Sashiko comment is partially valid - you change the ABI in incompatible > way, by requiring a new compatible. Commit msg should briefly explain > the impact, e.g. that there is no impact because phy was not > implemented by Linux and was not described in the binding. > > OTOH, adding simple-mfd means children have no dependency on the parent, > so this should be considered or even explicitly mentioned in commit msg > (parent clock is irrelevant to child, right?) > > OTOH2, you have now patchset dependency which is nowwhere explained. > Merging constraints are the most important part of cover letter so must > be clearly stated. IMO, should be stated also here, because many > maintainers do not read cover letters. Or just decouple dependencies > with using 'compatibles' pattern (see Qualcomm msm/mdss display > bindings). I wonder, wouldn't it be better to write a driver which binds to st,stm32mp25-syscfg , handles the SYSCFG clock, and does some of_platform_populate() to bring up the PHYs (DT subnodes) ? I think that would resolve the ABI break problem, since we wouldn't need the simple-mfd compatible anymore. And it would also correctly handle the SYSCFG clock. What do you think ?