From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from lithops.sigma-star.at (mailout.nod.at [116.203.167.152]) (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 E1E191EA7F4; Sat, 29 Nov 2025 15:33:41 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=116.203.167.152 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1764430424; cv=none; b=fG8JHKWehaw5NZonCLFAUTN0YGeI8O5NZtahX34XJRUzu8BTDY4cdIlSpnjLOaQAMsLV/UShiuSNp98Ek4tLx+DQhJb3YRzkGCm0S5HbK+eJwT4oU3sKsBCicVTujpxey0GWf+fHpBJ7MMpueSbEOffbw7/X5EngD+usYWW8Wh0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1764430424; c=relaxed/simple; bh=dU7B6z+rZCixYSv6NG9Z/njREZ0U4zpgTam0UXKn0nA=; h=Date:From:To:Cc:Message-ID:In-Reply-To:References:Subject: MIME-Version:Content-Type; b=hANRHe/QKXRQbeW4CpUzyCgLzftHoSbnOhhUNVjuzMu7EUyeqUhnnKTQcGT0T4m1IjSNoeMitkzOsZdZXvZuuNMmmI51E0Sa0pzHukxFGZ26WVc8ot1J/Qsl/atbtVGNYHnHa5Wyw1w/RSwo/oLYSB45pTIcF7tjuBX0Ex2e3Ic= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=nod.at; spf=fail smtp.mailfrom=nod.at; arc=none smtp.client-ip=116.203.167.152 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=nod.at Authentication-Results: smtp.subspace.kernel.org; spf=fail smtp.mailfrom=nod.at Received: from localhost (localhost [127.0.0.1]) by lithops.sigma-star.at (Postfix) with ESMTP id A0A9111C05F; Sat, 29 Nov 2025 16:33:39 +0100 (CET) Received: from lithops.sigma-star.at ([127.0.0.1]) by localhost (lithops.sigma-star.at [127.0.0.1]) (amavisd-new, port 10032) with ESMTP id R5GMfTpW88Zp; Sat, 29 Nov 2025 16:33:39 +0100 (CET) Received: from localhost (localhost [127.0.0.1]) by lithops.sigma-star.at (Postfix) with ESMTP id 2D88E2C14AB; Sat, 29 Nov 2025 16:33:39 +0100 (CET) Received: from lithops.sigma-star.at ([127.0.0.1]) by localhost (lithops.sigma-star.at [127.0.0.1]) (amavisd-new, port 10026) with ESMTP id zEXPoMPlw85S; Sat, 29 Nov 2025 16:33:39 +0100 (CET) Received: from lithops.sigma-star.at (lithops.sigma-star.at [195.201.40.130]) by lithops.sigma-star.at (Postfix) with ESMTP id E70CE2C14AA; Sat, 29 Nov 2025 16:33:38 +0100 (CET) Date: Sat, 29 Nov 2025 16:33:38 +0100 (CET) From: Richard Weinberger To: Krzysztof Kozlowski Cc: linux-kernel , linux-omap , devicetree , Arnd Bergmann , Lee Jones , dakr , "Rafael J. Wysocki" , Greg Kroah-Hartman , Mark Brown , tony , rogerq , khilman , Andreas Kemnade , aaro koskinen , Conor Dooley , Krzysztof Kozlowski , robh Message-ID: <771947541.4509.1764430418744.JavaMail.zimbra@nod.at> In-Reply-To: <7d9fcf24-5ad5-48cf-b36d-83025976f3aa@kernel.org> References: <20251129142042.344359-1-richard@nod.at> <20251129142042.344359-2-richard@nod.at> <7d9fcf24-5ad5-48cf-b36d-83025976f3aa@kernel.org> Subject: Re: [PATCH 1/4] dt-bindings: Document new common property: has-inaccessible-regs 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-Transfer-Encoding: quoted-printable X-Mailer: Zimbra 8.8.12_GA_3807 (ZimbraWebClient - FF144 (Linux)/8.8.12_GA_3809) Thread-Topic: dt-bindings: Document new common property: has-inaccessible-regs Thread-Index: bPmBJJrGVUd4KMbl9WY311auULoC4Q== ----- Urspr=C3=BCngliche Mail ----- > Von: "Krzysztof Kozlowski" > On 29/11/2025 15:20, Richard Weinberger wrote: >> This property is used to denote that a certain register map contains >> registers that are inaccessible under conditions only a device driver >> can know. >=20 > So device driver controls fully their exposure via sysfs. >=20 > Binding cannot help here at all. The driver does not expose them via sysfs, it's the regmap framework via de= bugfs. =20 >> The purpose of this property is to disable register access through debug >> facilities outside of the device driver. >=20 > You described OS policy which is not suitable for bindings at all. Plus > commit msg really mixes up two separate points - buggy driver which > fails to properly set regmap (or other facility) with some DT-based > restrictions. I kind of expected this answer. ;-) Currently arch/arm/boot/dts/ti/omap/dra7-l4.dtsi binds CTRL_MODULE_CORE to = the syscon mfd driver and various child nodes bind to subranges. e.g. scm_conf: scm_conf@0 { compatible =3D "syscon", "simple-bus"; reg =3D <0x0 0x1400>; #address-cells =3D <1>; #size-cells =3D <1>; ranges =3D <0 0x0 0x1400>; has-inaccessible-regs; pbias_regulator: pbias_regulator@e00 { compatible =3D "ti,pbias-dra7", "ti,pbias-omap"; reg =3D <0xe00 0x4>; syscon =3D <&scm_conf>; pbias_mmc_reg: pbias_mmc_omap5 { regulator-name =3D "pbias_mmc_omap5"; regulator-min-microvolt =3D <1800000>; regulator-max-microvolt =3D <3300000>; }; =20 }; =20 phy_gmii_sel: phy-gmii-sel@554 { compatible =3D "ti,dra7xx-phy-gmii-sel"; reg =3D <0x554 0x4>; #phy-cells =3D <1>; }; =20 scm_conf_clocks: clocks { #address-cells =3D <1>; #size-cells =3D <0>; }; =20 }; So, drivers like ti,pbias-dra7 or ti,dra7xx-phy-gmii-sel touch only registe= rs they know about and this works well. But syscon manages the whole register map via regmap, and regmap exposes it= all via debugfs. What solution do you propose? Splitting reg =3D <0x0 0x1400> into many tiny fractions and not using an mf= d anymore? Thanks, //richard