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 CA27A1D8E07; Mon, 7 Oct 2024 15:59:40 +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=1728316780; cv=none; b=JcYLaM2L4i51Gq3hYV9jCsvTroGoaEzcEmnDutXjS24fNhJ9yaA93qB5pPNW5x4YDPG0lG/I8EUMKdZcDcGF+beiBDRrLzf500sGnsstLPca2oBpRN/nUDHlHqaSkJNB4oDPvzyA85VlXfbhYGN1QRPiBtQM12W4ieF+9t1UoZ8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1728316780; c=relaxed/simple; bh=fhPtbJcYuo2EIiYOBX9N2FPoMgTuRpLRKCd9jzg6Vt0=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=SDt0b1nfS40+Q/qIQyBzJBj7q3zKiy8RjwFUJwI7ixT1kgtyIZoE+Bbi4iOBtstNANudxeaGSqxRGj+wNs6a9Tw2YlctRXsWlvJN7ZvNv3RK/lPYV6tb6HYXSHybAQ5roAMhhTDy8gW8p30JyY9Gz39mFy3+9ewC7j+G84X/hPY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=kUsH9KoJ; 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="kUsH9KoJ" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 30748C4CEC6; Mon, 7 Oct 2024 15:59:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1728316780; bh=fhPtbJcYuo2EIiYOBX9N2FPoMgTuRpLRKCd9jzg6Vt0=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=kUsH9KoJ/pcRJzTf0yiA76pFtXQToF3xoqGGBMSO/255O9nNZJx396sPE1Qn1deZc VbEIMzU76zibDubgGE9FYQOsPiKXrpR6mOEM0/z8ZrDnRI7xE1ad+UZMcc67dii7Yf fu+Ti3BrJasdXWC9/KH/aWR8juwbZy0PietEoRxpUJHCxDSxx5i8kWv24prO34EePT rQMOx5pNzv553+BV2nKmuoONMyk81DN7HbL+OWsDwSQ32WNjrdCfar/3lysObkE7Ng V7kVxHq76AYgAlJyIV4Cm01BV3+1UDRYwq3DGXY3lDRablkJqXEUIRDscEcOMIlmOH Kn5FCb6rlGxjA== Date: Mon, 7 Oct 2024 10:59:39 -0500 From: Rob Herring To: POPESCU Catalin Cc: "ulf.hansson@linaro.org" , "krzk+dt@kernel.org" , "conor+dt@kernel.org" , "p.zabel@pengutronix.de" , "linux-mmc@vger.kernel.org" , "devicetree@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "m.felsch@pengutronix.de" , GEO-CHHER-bsp-development Subject: Re: [PATCH 1/2] dt-bindings: mmc: mmc-pwrseq-simple: add support for reset control Message-ID: <20241007155939.GA849826-robh@kernel.org> References: <20241004120740.2887776-1-catalin.popescu@leica-geosystems.com> <20241005182632.GA496820-robh@kernel.org> <92a27d06-cd37-42ff-ac48-687981d24d41@leica-geosystems.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=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <92a27d06-cd37-42ff-ac48-687981d24d41@leica-geosystems.com> On Mon, Oct 07, 2024 at 03:32:42PM +0000, POPESCU Catalin wrote: > On 05/10/2024 20:26, Rob Herring wrote: > > [Some people who received this message don't often get email from robh@kernel.org. Learn why this is important at https://aka.ms/LearnAboutSenderIdentification ] > > > > This email is not from Hexagon’s Office 365 instance. Please be careful while clicking links, opening attachments, or replying to this email. > > > > > > On Fri, Oct 04, 2024 at 02:07:39PM +0200, Catalin Popescu wrote: > >> Add compatible value "mmc-pwrseq-simple-reset" to support reset control > >> instead of gpios. Reset controls being refcounted, they allow to use > >> shared resets or gpios across drivers. Support of reset control is > >> limited to one single reset control. > > Can't you do this without a binding change? Just use reset controls when > > there is only 1 GPIO. > > That's a good question. The idea was to keep in place the gpio support > w/o impacting any platform using pwrseq-simple. Why would it matter? If not shared, then the behavior should be the same. If shared, we want to maintain the broken behavior? > > Also, later on when support for a list of reset gpios will be added to > the reset framework, this would not work anymore... Why not? How an OS handles reset-gpios is up to the OS. It can evolve. The binding can't evolve because it is an ABI. Also, a list is kind of broken to begin with for a "generic" binding. What's the order the lines should be asserted/deasserted? What about timing requirements? You don't know because every device is different. This binding would not be accepted now, so extending it is questionable. Rob