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 1EAF936B; Sat, 29 Nov 2025 15:44:50 +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=1764431091; cv=none; b=OWHSbD+YOjc9cemR4A8O2AZ8mvBJBO1/6jyfwnt93UCaIl2sZ41kaoa14g588+5CtHGnV6T5VrkoK833HS9O5PACoNMcELtfE5QfMAURnpH0xRNn+9W0L9SI4wakf8l1YyqZ0XmX6WSPyk449br90320uZSQBWRIZ6QFIaaszIw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1764431091; c=relaxed/simple; bh=0UANz+DgS6lbWIrceFwDIral2u/fvRmP+7PtS4MXcYI=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=iAHs8dlh0qRdUrXQx9x4dBL9GJsyn7FDpT7cBnrjyJN38vmiWQ/sm7DtBkn9MG91tOZBz4KV5MPkM5LTdlRFDIYWprVTHJ+fk1mAW6wjDQVg7TCtoKYWpzAfFleQQo7qAH61EUfy0EnSFMunkiKewf/ZYRO+34bOiHQ19c3zh2s= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=ZXoS9j/q; 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="ZXoS9j/q" Received: by smtp.kernel.org (Postfix) with ESMTPSA id CD81DC4CEF7; Sat, 29 Nov 2025 15:44:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1764431090; bh=0UANz+DgS6lbWIrceFwDIral2u/fvRmP+7PtS4MXcYI=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=ZXoS9j/q72buF0f1wJAPgpewZ8Lz6+0apL/gWGY5ZRMgeutubTa77wj7A8FXqYjz5 SQufS3a6jc5W2Cze5kzp+FxmaY+xMyK3ZfkyzOeoeb9IpTYriE2tyVYwomTOWBPbwl vtwBU14yKtVvP07LNvPRdz1DuEhMaXnURAvbyJELmDLAn2iTesmoMcWOKt7pK4L/ZN t7e3/7DlPJfZfK06X2R/d5E9sK5JsRNv8F0EFSPKcjW8A9obxOPPAF0yFp9idATvqC 2xOW46FNTsnGm4b0G/tv7g6TujvwZm8uhNgF4y13h0KXjW3woPYs0MNfjSiMn7mA+/ Hd2b0K2loMoKQ== Message-ID: <8b0e2b8a-314f-40ee-8f30-c281f3799705@kernel.org> Date: Sat, 29 Nov 2025 16:44:44 +0100 Precedence: bulk X-Mailing-List: linux-omap@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH 1/4] dt-bindings: Document new common property: has-inaccessible-regs To: Richard Weinberger 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 References: <20251129142042.344359-1-richard@nod.at> <20251129142042.344359-2-richard@nod.at> <7d9fcf24-5ad5-48cf-b36d-83025976f3aa@kernel.org> <771947541.4509.1764430418744.JavaMail.zimbra@nod.at> From: Krzysztof Kozlowski Content-Language: en-US Autocrypt: addr=krzk@kernel.org; keydata= xsFNBFVDQq4BEAC6KeLOfFsAvFMBsrCrJ2bCalhPv5+KQF2PS2+iwZI8BpRZoV+Bd5kWvN79 cFgcqTTuNHjAvxtUG8pQgGTHAObYs6xeYJtjUH0ZX6ndJ33FJYf5V3yXqqjcZ30FgHzJCFUu JMp7PSyMPzpUXfU12yfcRYVEMQrmplNZssmYhiTeVicuOOypWugZKVLGNm0IweVCaZ/DJDIH gNbpvVwjcKYrx85m9cBVEBUGaQP6AT7qlVCkrf50v8bofSIyVa2xmubbAwwFA1oxoOusjPIE J3iadrwpFvsZjF5uHAKS+7wHLoW9hVzOnLbX6ajk5Hf8Pb1m+VH/E8bPBNNYKkfTtypTDUCj NYcd27tjnXfG+SDs/EXNUAIRefCyvaRG7oRYF3Ec+2RgQDRnmmjCjoQNbFrJvJkFHlPeHaeS BosGY+XWKydnmsfY7SSnjAzLUGAFhLd/XDVpb1Een2XucPpKvt9ORF+48gy12FA5GduRLhQU vK4tU7ojoem/G23PcowM1CwPurC8sAVsQb9KmwTGh7rVz3ks3w/zfGBy3+WmLg++C2Wct6nM Pd8/6CBVjEWqD06/RjI2AnjIq5fSEH/BIfXXfC68nMp9BZoy3So4ZsbOlBmtAPvMYX6U8VwD TNeBxJu5Ex0Izf1NV9CzC3nNaFUYOY8KfN01X5SExAoVTr09ewARAQABzSVLcnp5c3p0b2Yg S296bG93c2tpIDxrcnprQGtlcm5lbC5vcmc+wsGVBBMBCgA/AhsDBgsJCAcDAgYVCAIJCgsE FgIDAQIeAQIXgBYhBJvQfg4MUfjVlne3VBuTQ307QWKbBQJoF1BKBQkWlnSaAAoJEBuTQ307 QWKbHukP/3t4tRp/bvDnxJfmNdNVn0gv9ep3L39IntPalBFwRKytqeQkzAju0whYWg+R/rwp +r2I1Fzwt7+PTjsnMFlh1AZxGDmP5MFkzVsMnfX1lGiXhYSOMP97XL6R1QSXxaWOpGNCDaUl ajorB0lJDcC0q3xAdwzRConxYVhlgmTrRiD8oLlSCD5baEAt5Zw17UTNDnDGmZQKR0fqLpWy 786Lm5OScb7DjEgcA2PRm17st4UQ1kF0rQHokVaotxRM74PPDB8bCsunlghJl1DRK9s1aSuN hL1Pv9VD8b4dFNvCo7b4hfAANPU67W40AaaGZ3UAfmw+1MYyo4QuAZGKzaP2ukbdCD/DYnqi tJy88XqWtyb4UQWKNoQqGKzlYXdKsldYqrLHGoMvj1UN9XcRtXHST/IaLn72o7j7/h/Ac5EL 8lSUVIG4TYn59NyxxAXa07Wi6zjVL1U11fTnFmE29ALYQEXKBI3KUO1A3p4sQWzU7uRmbuxn naUmm8RbpMcOfa9JjlXCLmQ5IP7Rr5tYZUCkZz08LIfF8UMXwH7OOEX87Y++EkAB+pzKZNNd hwoXulTAgjSy+OiaLtuCys9VdXLZ3Zy314azaCU3BoWgaMV0eAW/+gprWMXQM1lrlzvwlD/k whyy9wGf0AEPpLssLVt9VVxNjo6BIkt6d1pMg6mHsUEVzsFNBFVDXDQBEADNkrQYSREUL4D3 Gws46JEoZ9HEQOKtkrwjrzlw/tCmqVzERRPvz2Xg8n7+HRCrgqnodIYoUh5WsU84N03KlLue MNsWLJBvBaubYN4JuJIdRr4dS4oyF1/fQAQPHh8Thpiz0SAZFx6iWKB7Qrz3OrGCjTPcW6ei OMheesVS5hxietSmlin+SilmIAPZHx7n242u6kdHOh+/SyLImKn/dh9RzatVpUKbv34eP1wA GldWsRxbf3WP9pFNObSzI/Bo3kA89Xx2rO2roC+Gq4LeHvo7ptzcLcrqaHUAcZ3CgFG88CnA 6z6lBZn0WyewEcPOPdcUB2Q7D/NiUY+HDiV99rAYPJztjeTrBSTnHeSBPb+qn5ZZGQwIdUW9 YegxWKvXXHTwB5eMzo/RB6vffwqcnHDoe0q7VgzRRZJwpi6aMIXLfeWZ5Wrwaw2zldFuO4Dt 91pFzBSOIpeMtfgb/Pfe/a1WJ/GgaIRIBE+NUqckM+3zJHGmVPqJP/h2Iwv6nw8U+7Yyl6gU BLHFTg2hYnLFJI4Xjg+AX1hHFVKmvl3VBHIsBv0oDcsQWXqY+NaFahT0lRPjYtrTa1v3tem/ JoFzZ4B0p27K+qQCF2R96hVvuEyjzBmdq2esyE6zIqftdo4MOJho8uctOiWbwNNq2U9pPWmu 4vXVFBYIGmpyNPYzRm0QPwARAQABwsF8BBgBCgAmAhsMFiEEm9B+DgxR+NWWd7dUG5NDfTtB YpsFAmgXUF8FCRaWWyoACgkQG5NDfTtBYptO0w//dlXJs5/42hAXKsk+PDg3wyEFb4NpyA1v qmx7SfAzk9Hf6lWwU1O6AbqNMbh6PjEwadKUk1m04S7EjdQLsj/MBSgoQtCT3MDmWUUtHZd5 RYIPnPq3WVB47GtuO6/u375tsxhtf7vt95QSYJwCB+ZUgo4T+FV4hquZ4AsRkbgavtIzQisg Dgv76tnEv3YHV8Jn9mi/Bu0FURF+5kpdMfgo1sq6RXNQ//TVf8yFgRtTUdXxW/qHjlYURrm2 H4kutobVEIxiyu6m05q3e9eZB/TaMMNVORx+1kM3j7f0rwtEYUFzY1ygQfpcMDPl7pRYoJjB dSsm0ZuzDaCwaxg2t8hqQJBzJCezTOIkjHUsWAK+tEbU4Z4SnNpCyM3fBqsgYdJxjyC/tWVT AQ18NRLtPw7tK1rdcwCl0GFQHwSwk5pDpz1NH40e6lU+NcXSeiqkDDRkHlftKPV/dV+lQXiu jWt87ecuHlpL3uuQ0ZZNWqHgZoQLXoqC2ZV5KrtKWb/jyiFX/sxSrodALf0zf+tfHv0FZWT2 zHjUqd0t4njD/UOsuIMOQn4Ig0SdivYPfZukb5cdasKJukG1NOpbW7yRNivaCnfZz6dTawXw XRIV/KDsHQiyVxKvN73bThKhONkcX2LWuD928tAR6XMM2G5ovxLe09vuOzzfTWQDsm++9UKF a/A= In-Reply-To: <771947541.4509.1764430418744.JavaMail.zimbra@nod.at> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit On 29/11/2025 16:33, Richard Weinberger wrote: > ----- Ursprüngliche 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. >> >> So device driver controls fully their exposure via sysfs. >> >> Binding cannot help here at all. > > The driver does not expose them via sysfs, it's the regmap framework via debugfs. Driver always tells the regmap which registers are valid. This is not a new problem, we had it in several devices and fixed drivers. > >>> The purpose of this property is to disable register access through debug >>> facilities outside of the device driver. >> >> 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 = "syscon", "simple-bus"; > reg = <0x0 0x1400>; > #address-cells = <1>; > #size-cells = <1>; > ranges = <0 0x0 0x1400>; > has-inaccessible-regs; > > pbias_regulator: pbias_regulator@e00 { > compatible = "ti,pbias-dra7", "ti,pbias-omap"; > reg = <0xe00 0x4>; > syscon = <&scm_conf>; > pbias_mmc_reg: pbias_mmc_omap5 { > regulator-name = "pbias_mmc_omap5"; > regulator-min-microvolt = <1800000>; > regulator-max-microvolt = <3300000>; > }; > }; > > phy_gmii_sel: phy-gmii-sel@554 { > compatible = "ti,dra7xx-phy-gmii-sel"; > reg = <0x554 0x4>; > #phy-cells = <1>; > }; > > scm_conf_clocks: clocks { > #address-cells = <1>; > #size-cells = <0>; > }; > }; > > So, drivers like ti,pbias-dra7 or ti,dra7xx-phy-gmii-sel touch only registers > 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 = <0x0 0x1400> into many tiny fractions and not using an mfd anymore? Fix the driver. In your case, the syscon driver. Best regards, Krzysztof