From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-il1-f181.google.com (mail-il1-f181.google.com [209.85.166.181]) (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 04E5D5387 for ; Thu, 4 Aug 2022 20:25:24 +0000 (UTC) Received: by mail-il1-f181.google.com with SMTP id o14so489570ilt.2 for ; Thu, 04 Aug 2022 13:25:24 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-message-state:from:to:cc; bh=VCrvf/3BTjJQt0YH832xOkI02Lgn0gW1RupzGTTYZ48=; b=NdgjSuK6ENr4QGU2KU/V37477EmPTT4VDynNWWhJjMgxTUFsmhcI++wGdVEjF5kpAw OXQQxRZ5Oz5NYkzigYdkzKN1o0FcofwNv17IQ+H4Z3KnGEjqEzgJESmVnBuvgrINMNvo t2/431aiQRdIgzXkQcwNvQw41xgULbD47WtRlTVOQ3QONJyc0jvP3Ot/A6+7QCWUQaPc /QBvWbH8dVr17JnVUxODj+K/ZSdalfzrT7z3/jqd9lHegt0AoTJ13/i/o2D3QNiLhKgB Lv1dcBd52+BhfqdT5swq9SMuvXlUrFftadNhNHNn8738SV+czHklHpds75Z20lNuGbz+ orfw== X-Gm-Message-State: ACgBeo0mjq2qkyX7DPk4M/jMOfuENT09zCsoax2T2lPSHTLgOjHYboEf SvBa+jVElOCeu6U5AA5/QA== X-Google-Smtp-Source: AA6agR4IEIf2V1e+SjXZ08QE3XEDkC/YH4eaoedz452FM2FY+ToqoUd9zND/cdfAZ57pVgDo6kT9lA== X-Received: by 2002:a05:6e02:2188:b0:2dd:f749:512d with SMTP id j8-20020a056e02218800b002ddf749512dmr1587415ila.216.1659644723968; Thu, 04 Aug 2022 13:25:23 -0700 (PDT) Received: from robh.at.kernel.org ([64.188.179.248]) by smtp.gmail.com with ESMTPSA id d18-20020a92c192000000b002dd028f5ef5sm811076ilh.38.2022.08.04.13.25.22 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 04 Aug 2022 13:25:23 -0700 (PDT) Received: (nullmailer pid 304396 invoked by uid 1000); Thu, 04 Aug 2022 20:25:22 -0000 Date: Thu, 4 Aug 2022 14:25:22 -0600 From: Rob Herring To: Samuel Holland Cc: Liam Girdwood , Mark Brown , Chen-Yu Tsai , Jernej Skrabec , Krzysztof Kozlowski , Maxime Ripard , devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-sunxi@lists.linux.dev Subject: Re: [PATCH v2 3/4] regulator: dt-bindings: Add Allwinner D1 LDOs Message-ID: <20220804202522.GC4145453-robh@kernel.org> References: <20220802053213.3645-1-samuel@sholland.org> <20220802053213.3645-4-samuel@sholland.org> <20220802150452.GA86158-robh@kernel.org> <918a83a7-1b8d-04b1-4f7b-386fc800e653@sholland.org> Precedence: bulk X-Mailing-List: linux-sunxi@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <918a83a7-1b8d-04b1-4f7b-386fc800e653@sholland.org> On Wed, Aug 03, 2022 at 10:03:07PM -0500, Samuel Holland wrote: > Hi Rob, > > Thanks again for your review. > > On 8/2/22 10:04 AM, Rob Herring wrote: > > On Tue, Aug 02, 2022 at 12:32:12AM -0500, Samuel Holland wrote: > >> The Allwinner D1 SoC contains two pairs of in-package LDOs. One pair is > >> for general purpose use. LDOA generally powers the board's 1.8 V rail. > >> LDOB generally powers the in-package DRAM, where applicable. > >> > >> The other pair of LDOs powers the analog power domains inside the SoC, > >> including the audio codec, thermal sensor, and ADCs. These LDOs require > >> a 0.9 V bandgap voltage reference. The calibration value for the voltage > >> reference is stored in an eFuse, accessed via an NVMEM cell. > >> > >> Neither LDO control register is in its own MMIO range; instead, each > >> regulator device relies on a regmap/syscon exported by its parent. > >> > >> Signed-off-by: Samuel Holland > >> --- > >> > >> Changes in v2: > >> - Remove syscon property from bindings > >> - Update binding examples to fix warnings and provide context > >> > >> .../allwinner,sun20i-d1-analog-ldos.yaml | 65 +++++++++++++++++++ > >> .../allwinner,sun20i-d1-system-ldos.yaml | 57 ++++++++++++++++ > >> 2 files changed, 122 insertions(+) > >> create mode 100644 Documentation/devicetree/bindings/regulator/allwinner,sun20i-d1-analog-ldos.yaml > >> create mode 100644 Documentation/devicetree/bindings/regulator/allwinner,sun20i-d1-system-ldos.yaml > >> > >> diff --git a/Documentation/devicetree/bindings/regulator/allwinner,sun20i-d1-analog-ldos.yaml b/Documentation/devicetree/bindings/regulator/allwinner,sun20i-d1-analog-ldos.yaml > >> new file mode 100644 > >> index 000000000000..19c984ef4e53 > >> --- /dev/null > >> +++ b/Documentation/devicetree/bindings/regulator/allwinner,sun20i-d1-analog-ldos.yaml > >> @@ -0,0 +1,65 @@ > >> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) > >> +%YAML 1.2 > >> +--- > >> +$id: http://devicetree.org/schemas/regulator/allwinner,sun20i-d1-analog-ldos.yaml# > >> +$schema: http://devicetree.org/meta-schemas/core.yaml# > >> + > >> +title: Allwinner D1 Analog LDOs > >> + > >> +description: > >> + Allwinner D1 contains a set of LDOs which are designed to supply analog power > >> + inside and outside the SoC. They are controlled by a register within the audio > >> + codec MMIO space, but which is not part of the audio codec clock/reset domain. > >> + > >> +maintainers: > >> + - Samuel Holland > >> + > >> +properties: > >> + compatible: > >> + enum: > >> + - allwinner,sun20i-d1-analog-ldos > >> + > >> + nvmem-cells: > >> + items: > >> + - description: NVMEM cell for the calibrated bandgap reference trim value > >> + > >> + nvmem-cell-names: > >> + items: > >> + - const: bg_trim > >> + > >> +patternProperties: > >> + "^(aldo|hpldo)$": > > > > '^(a|hp)ldo$' > > > >> + type: object > >> + $ref: regulator.yaml# > > > > unevaluatedProperties: false > > > >> + > >> +required: > >> + - compatible > >> + - nvmem-cells > >> + - nvmem-cell-names > >> + > >> +unevaluatedProperties: false > >> + > >> +examples: > >> + - | > >> + audio-codec@2030000 { > >> + compatible = "simple-mfd", "syscon"; > > > > Needs a specific compatible. Obviously there's some other functionality > > here if this is an 'audio-codec'. > > I am not yet ready to submit the binding or driver for the audio codec, as I > still need to work out the details for jack detection (and some other issues). > If I added the specific audio codec compatible now, without the properties > required for the sound driver, that would create backward compatibility issues, > right? Only if something used it. > My intention is to add the specific compatible along with the ASoC support. > > > 'simple-mfd' also means the child nodes have zero dependence on the > > parent node and its resources. > > That is correct. The regulators have zero dependencies on the audio codec > resources (clocks/resets/etc.). The _only_ relationship is the overlapping > address of the MMIO register. Okay. > > >> + reg = <0x2030000 0x1000>; > >> + > >> + regulators { > >> + compatible = "allwinner,sun20i-d1-analog-ldos"; > > > > Is there a defined set of registers for these regulators? If so, put > > them into 'reg'. > > What do you suggest for 'ranges' in the parent device? I ask because the > SRAM/system controller binding requires an empty 'ranges' property. I think you are misreading 'ranges: true'. That just means the property can be present, not that it's type is boolean. > With empty 'ranges', the child has to compute the relative address for use with > the parent's regmap, but maybe that is okay? We should probably have some sort of 'address to regmap offset' helper that works no matter what ranges has. In most cases, while I require 'reg', unless the child nodes use a mixed up set of registers, Linux doesn't currently use 'reg'. You can also just hardcode the offsets in your driver. > >> + nvmem-cells = <&bg_trim>; > >> + nvmem-cell-names = "bg_trim"; > >> + > >> + reg_aldo: aldo { > >> + regulator-min-microvolt = <1800000>; > >> + regulator-max-microvolt = <1800000>; > >> + }; > >> + > >> + reg_hpldo: hpldo { > >> + regulator-min-microvolt = <1800000>; > >> + regulator-max-microvolt = <1800000>; > >> + }; > >> + }; > >> + }; > >> + > >> +... > >> diff --git a/Documentation/devicetree/bindings/regulator/allwinner,sun20i-d1-system-ldos.yaml b/Documentation/devicetree/bindings/regulator/allwinner,sun20i-d1-system-ldos.yaml > >> new file mode 100644 > >> index 000000000000..c95030a827d6 > >> --- /dev/null > >> +++ b/Documentation/devicetree/bindings/regulator/allwinner,sun20i-d1-system-ldos.yaml > >> @@ -0,0 +1,57 @@ > >> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) > >> +%YAML 1.2 > >> +--- > >> +$id: http://devicetree.org/schemas/regulator/allwinner,sun20i-d1-system-ldos.yaml# > >> +$schema: http://devicetree.org/meta-schemas/core.yaml# > >> + > >> +title: Allwinner D1 System LDOs > >> + > >> +description: > >> + Allwinner D1 contains a pair of general-purpose LDOs which are designed to > >> + supply power inside and outside the SoC. They are controlled by a register > >> + within the system control MMIO space. > >> + > >> +maintainers: > >> + - Samuel Holland > >> + > >> +properties: > >> + compatible: > >> + enum: > >> + - allwinner,sun20i-d1-system-ldos > >> + > >> +patternProperties: > >> + "^(ldoa|ldob)$": > > > > '^ldo[ab]$' > > > > Any reason the naming is not consistent with 'ldo' as the prefix or > > suffix? > > All four names match the pin names from the SoC datasheet. Good enough for me. Rob