From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 080D7352033; Thu, 28 May 2026 22:34:44 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780007686; cv=none; b=TAEAaYnrzmIKy5ViWM3GL55MVvssiZi/Wt9Hem2AiUAaLTIsGmThWzSGSDW4UIVmc0TaptK89mxM/iXQvPdgnYJ/oHtujYU6EDrLWD+V2CNK5G6qzogKd64ewPQJiq/1vCr874zQviM7dUouexq+3dht8wJWI71BKmjI0MCU07c= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780007686; c=relaxed/simple; bh=T+A8B0Lkq8CucUJxIXZD63zdSoO1bk3N54bukijHHms=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=mECBLH/Yo+NN4lzSEG6JMB7l6VHFOMuTiOP/I2HDStTP/V7KUXHBubXsT0f1KVInWb9vi+i3q4K+XcELLgp0RMtI6CnBMHsVqWTK2VaP73GNvLcjbsTP0s4OlAQT1NY5CT+SaUDVidMmj/ujHvVF3kFKsUp319yLPv9YX+2jeBQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=Wixk+w0z; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="Wixk+w0z" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 990D61F000E9; Thu, 28 May 2026 22:34:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1780007684; bh=T+A8B0Lkq8CucUJxIXZD63zdSoO1bk3N54bukijHHms=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=Wixk+w0zrDvzUA9+b715i8Nur/PrQSMHRzRElj+lxfCwP2zEBGYfdtDffUNEG2gEz mcrTTh9lXiLPw6iEFXOPBgNqjmx5pp0CRQLy7miWuMmgqZ2UkTLe6uA9vwEw0WUn6w 08eeTuPI45sC8JYHcgyqYR2qPqDt/z6eADE9v0kPx7ExN0U+GAMPR+FHtnWJzaLbAZ 0T8ZkEAlVLDRqCM58Vdd4S5du5fRVxI7JvMDo7OZUsVpL8KsYUvND+QDo/2fryq7lY Zyil7d9oGYL2nrSETAwqRDmpeWQMzR1u74OKEwl5/ynx2hzRq+C8yepizpdIUXiPbD aG/KrVbf6hL/Q== Date: Thu, 28 May 2026 23:34:40 +0100 From: Conor Dooley To: Guenter Roeck Cc: linux-hwmon@vger.kernel.org, Lars Randers , Conor Dooley , Jonathan Corbet , Shuah Khan , Daire McNamara , linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-riscv@lists.infradead.org, Valentina.FernandezAlanis@microchip.com Subject: Re: [RFC] hwmon: add a driver for the temp/voltage sensor on PolarFire SoC Message-ID: <20260528-defog-lasso-84891a72775a@spud> References: <20260527-earring-bully-eb4a268c2e68@spud> Precedence: bulk X-Mailing-List: linux-doc@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="/dY6UJR7eVAiYQsM" Content-Disposition: inline In-Reply-To: --/dY6UJR7eVAiYQsM Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Wed, May 27, 2026 at 09:07:20PM -0700, Guenter Roeck wrote: > On Wed, May 27, 2026 at 10:06:11AM +0100, Conor Dooley wrote: > > From: Lars Randers > >=20 > > Add a driver for the temperature and voltage sensors on PolarFire SoC. > > The temperature reports how hot the die is, and the voltages are the > > SoC's 1.05, 1.8 and 2.5 volt rails respectively. > >=20 > > The hardware supports alarms in theory, but there is an unconfirmed > > erratum that prevents clearing them once triggered, so no support is > > added. > >=20 > > The hardware measures voltage with 16 bits, of which 1 is a sign bit and > > the remainder holds the voltage as a fixed point integer value. It's > > improbable that the hardware will work if the voltages are negative, so > > the driver ignores the sign bits. > >=20 > > There's no dt support etc here because this is the child of a simple-mfd > > syscon. > >=20 > > Signed-off-by: Lars Randers > > Co-developed-by: Conor Dooley > > Signed-off-by: Conor Dooley > > --- > > Guenter, there's one question here about the unit that update_interval > > is in, I didn't see anyone else using us, but I assume that's okay since > > the resolution that ms would give would be 8 steps only? > > RFC cos the question is also in the driver as a comment. > >=20 >=20 > That just came up in a different context. We'll add a new standard attrib= ute > update_interval_us. The existing attribute MUST use ms. Everything else > would be an ABI violation. Cool. Sounds like Ferdinand is working on that based on the other thread. Do you think I should support both update_interval and update_interval_us in this driver? If yes, should I do the ms version now and add the us version later once Ferdinand's work is complete? Cheers, Conor. --/dY6UJR7eVAiYQsM Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iHUEABYKAB0WIQRh246EGq/8RLhDjO14tDGHoIJi0gUCahjDAAAKCRB4tDGHoIJi 0umqAQCFXSx/b46Px06mubHpDqQJZ3Dlo4pIUwEr8Pe8FDNJVQD/SkBJj7iAvvsa IVlWnxRmcMZb0DAcbwlLRhhdwJdPOgc= =0zap -----END PGP SIGNATURE----- --/dY6UJR7eVAiYQsM-- From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id F164DCD4F54 for ; Thu, 28 May 2026 22:35:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:Content-Type: List-Subscribe:List-Help:List-Post:List-Archive:List-Unsubscribe:List-Id: In-Reply-To:MIME-Version:References:Message-ID:Subject:Cc:To:From:Date: Reply-To:Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date :Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=h5/OZtRSO00bX8NlH6DdQ2lTxAxCDsXlZxV9Dt8pCe4=; b=2poH3j+1TIq1Jt02O3bULN+CFZ qNZtL/cvw2a2+s5DeVcOVKpDUi8WMXheqNJzC/RyjneoOMSsNEaZO/aaQVigaF/cL3xHCqNKAhrG9 QPHcHlCGhqIg8bAcdMu2tceBVtLt2Wi8WGZw+J7uXowYx51YqyRYJOdcNXsXqggMYewYRDtYTcqee 3a/lDg1UVr7V4CYruJybGCCwwkZXUQ5bzR5aoJhLVh9Rvmu3YQQ9Ucy0WxBa02PEISd6e6iXAvFSi CFxB2DPgOWqEmM3OPU58Et44itTZc2I59rigvpJQycaIMpwm6Xhj8DPC6IfgQjFefb5LPP3HSft6X cbnQ40oQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1wSjJQ-00000006UPB-30cJ; Thu, 28 May 2026 22:34:48 +0000 Received: from sea.source.kernel.org ([172.234.252.31]) by bombadil.infradead.org with esmtps (Exim 4.99.1 #2 (Red Hat Linux)) id 1wSjJN-00000006UOZ-1RbN for linux-riscv@lists.infradead.org; Thu, 28 May 2026 22:34:46 +0000 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by sea.source.kernel.org (Postfix) with ESMTP id CC22740B17; Thu, 28 May 2026 22:34:44 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 990D61F000E9; Thu, 28 May 2026 22:34:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1780007684; bh=T+A8B0Lkq8CucUJxIXZD63zdSoO1bk3N54bukijHHms=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=Wixk+w0zrDvzUA9+b715i8Nur/PrQSMHRzRElj+lxfCwP2zEBGYfdtDffUNEG2gEz mcrTTh9lXiLPw6iEFXOPBgNqjmx5pp0CRQLy7miWuMmgqZ2UkTLe6uA9vwEw0WUn6w 08eeTuPI45sC8JYHcgyqYR2qPqDt/z6eADE9v0kPx7ExN0U+GAMPR+FHtnWJzaLbAZ 0T8ZkEAlVLDRqCM58Vdd4S5du5fRVxI7JvMDo7OZUsVpL8KsYUvND+QDo/2fryq7lY Zyil7d9oGYL2nrSETAwqRDmpeWQMzR1u74OKEwl5/ynx2hzRq+C8yepizpdIUXiPbD aG/KrVbf6hL/Q== Date: Thu, 28 May 2026 23:34:40 +0100 From: Conor Dooley To: Guenter Roeck Cc: linux-hwmon@vger.kernel.org, Lars Randers , Conor Dooley , Jonathan Corbet , Shuah Khan , Daire McNamara , linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-riscv@lists.infradead.org, Valentina.FernandezAlanis@microchip.com Subject: Re: [RFC] hwmon: add a driver for the temp/voltage sensor on PolarFire SoC Message-ID: <20260528-defog-lasso-84891a72775a@spud> References: <20260527-earring-bully-eb4a268c2e68@spud> MIME-Version: 1.0 In-Reply-To: X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.9.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260528_153445_422729_975990BF X-CRM114-Status: GOOD ( 25.17 ) X-BeenThere: linux-riscv@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: multipart/mixed; boundary="===============9191623384967513427==" Sender: "linux-riscv" Errors-To: linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org --===============9191623384967513427== Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="/dY6UJR7eVAiYQsM" Content-Disposition: inline --/dY6UJR7eVAiYQsM Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Wed, May 27, 2026 at 09:07:20PM -0700, Guenter Roeck wrote: > On Wed, May 27, 2026 at 10:06:11AM +0100, Conor Dooley wrote: > > From: Lars Randers > >=20 > > Add a driver for the temperature and voltage sensors on PolarFire SoC. > > The temperature reports how hot the die is, and the voltages are the > > SoC's 1.05, 1.8 and 2.5 volt rails respectively. > >=20 > > The hardware supports alarms in theory, but there is an unconfirmed > > erratum that prevents clearing them once triggered, so no support is > > added. > >=20 > > The hardware measures voltage with 16 bits, of which 1 is a sign bit and > > the remainder holds the voltage as a fixed point integer value. It's > > improbable that the hardware will work if the voltages are negative, so > > the driver ignores the sign bits. > >=20 > > There's no dt support etc here because this is the child of a simple-mfd > > syscon. > >=20 > > Signed-off-by: Lars Randers > > Co-developed-by: Conor Dooley > > Signed-off-by: Conor Dooley > > --- > > Guenter, there's one question here about the unit that update_interval > > is in, I didn't see anyone else using us, but I assume that's okay since > > the resolution that ms would give would be 8 steps only? > > RFC cos the question is also in the driver as a comment. > >=20 >=20 > That just came up in a different context. We'll add a new standard attrib= ute > update_interval_us. The existing attribute MUST use ms. Everything else > would be an ABI violation. Cool. Sounds like Ferdinand is working on that based on the other thread. Do you think I should support both update_interval and update_interval_us in this driver? If yes, should I do the ms version now and add the us version later once Ferdinand's work is complete? Cheers, Conor. --/dY6UJR7eVAiYQsM Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iHUEABYKAB0WIQRh246EGq/8RLhDjO14tDGHoIJi0gUCahjDAAAKCRB4tDGHoIJi 0umqAQCFXSx/b46Px06mubHpDqQJZ3Dlo4pIUwEr8Pe8FDNJVQD/SkBJj7iAvvsa IVlWnxRmcMZb0DAcbwlLRhhdwJdPOgc= =0zap -----END PGP SIGNATURE----- --/dY6UJR7eVAiYQsM-- --===============9191623384967513427== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ linux-riscv mailing list linux-riscv@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-riscv --===============9191623384967513427==--