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 X-Spam-Level: X-Spam-Status: No, score=-3.7 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7CEC3C4338F for ; Sat, 31 Jul 2021 12:00:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 60BF460D07 for ; Sat, 31 Jul 2021 12:00:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232969AbhGaMAw (ORCPT ); Sat, 31 Jul 2021 08:00:52 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47340 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232957AbhGaMAw (ORCPT ); Sat, 31 Jul 2021 08:00:52 -0400 Received: from metis.ext.pengutronix.de (metis.ext.pengutronix.de [IPv6:2001:67c:670:201:290:27ff:fe1d:cc33]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 568DEC06175F for ; Sat, 31 Jul 2021 05:00:46 -0700 (PDT) Received: from drehscheibe.grey.stw.pengutronix.de ([2a0a:edc0:0:c01:1d::a2]) by metis.ext.pengutronix.de with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1m9nf1-0006Si-LC; Sat, 31 Jul 2021 14:00:11 +0200 Received: from [2a0a:edc0:0:900:1d::77] (helo=ptz.office.stw.pengutronix.de) by drehscheibe.grey.stw.pengutronix.de with esmtp (Exim 4.92) (envelope-from ) id 1m9nex-0007cy-2W; Sat, 31 Jul 2021 14:00:07 +0200 Received: from ukl by ptz.office.stw.pengutronix.de with local (Exim 4.92) (envelope-from ) id 1m9nex-0001JF-0C; Sat, 31 Jul 2021 14:00:07 +0200 Date: Sat, 31 Jul 2021 14:00:04 +0200 From: Uwe =?utf-8?Q?Kleine-K=C3=B6nig?= To: Stephen Boyd , Russell King Cc: alexandre.belloni@bootlin.com, Michael Turquette , thierry.reding@gmail.com, lee.jones@linaro.org, linux-clk@vger.kernel.org, linux-rtc@vger.kernel.org, Ludovic.Desroches@microchip.com, o.rempel@pengutronix.de, andy.shevchenko@gmail.com, aardelean@deviqon.com, linux-pwm@vger.kernel.org, Arnd Bergmann , broonie@kernel.org, Jonathan.Cameron@huawei.com, linux-arm-kernel@lists.infradead.org, a.zummo@towertech.it, linux-kernel@vger.kernel.org, linux-spi@vger.kernel.org, wsa@kernel.org, kernel@pengutronix.de, akpm@linux-foundation.org, torvalds@linux-foundation.org, Claudiu.Beznea@microchip.com Subject: Re: About clk maintainership [Was: Re: [PULL] Add variants of devm_clk_get for prepared and enabled clocks enabled clocks] Message-ID: <20210731120004.i3affxw7upl5y4c5@pengutronix.de> References: <20210722060654.nudpdtemosi64nlb@pengutronix.de> <20210722081817.2tsjzof4gvldq6ka@pengutronix.de> <20210723091331.wl33wtcvvnejuhau@pengutronix.de> <06e799be-b7c0-5b93-8586-678a449d2239@microchip.com> <20210728202547.7uvfwflpruku7yps@pengutronix.de> <20210728204033.GF22278@shell.armlinux.org.uk> <162771727997.714452.2303764341103276867@swboyd.mtv.corp.google.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="i6yytbqtmtyzj4jc" Content-Disposition: inline In-Reply-To: <162771727997.714452.2303764341103276867@swboyd.mtv.corp.google.com> X-SA-Exim-Connect-IP: 2a0a:edc0:0:c01:1d::a2 X-SA-Exim-Mail-From: ukl@pengutronix.de X-SA-Exim-Scanned: No (on metis.ext.pengutronix.de); SAEximRunCond expanded to false X-PTX-Original-Recipient: linux-pwm@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pwm@vger.kernel.org --i6yytbqtmtyzj4jc Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable Hi Russell, hi Stephen, On Sat, Jul 31, 2021 at 12:41:19AM -0700, Stephen Boyd wrote: > Quoting Russell King (Oracle) (2021-07-28 13:40:34) > > > I adapted the Subject in the hope to catch Stephen's and Michael's > > > attention. My impression is that this thread isn't on their radar yet, > > > but the topic here seems important enough to get a matching Subject. >=20 > The thread is on my radar but... >=20 > >=20 > > Have you thought about sending your pull request to the clk API > > maintainer (iow, me) ? I wasn't really aware that Russell has the clk API hat (or that this separate hat actually exists and this isn't purely a CCF topic). I assume I only did $ scripts/get_maintainer.pl -f drivers/clk/clk-devres.c which is where the current and new code implementing devm_clk_get et al lives. @Russell: What is your position here, do you like the approach of devm_clk_get_enabled? I can send a new pull request in your direction if you like it and are willing to take it. > +1 This patch doesn't fall under CCF maintainer. Given that CCF is the only implementer of devm_clk_get at least an Ack =66rom your side would still be good I guess? > Finally, this sort of patch has been discussed for years and I didn't > see any mention of those previous attempts in the patch series. Has > something changed since that time? I think we've got a bunch of hand > rolled devm things in the meantime but not much else.=20 I found a patch set adding devm variants of clk_enable (e.g. https://lore.kernel.org/patchwork/patch/755667/) but this approach is different as it also contains clk_get which IMHO makes more sense=20 The discussion considered wrapping get+enable at one point, but I didn't find a followup. > I still wonder if it would be better if we had some sort of DT binding > that said "turn this clk on when the driver probes this device and keep > it on until the driver is unbound". This doesn't sound like a hardware property and so I don't think this belongs into DT and I would be surprised if the dt maintainers would be willing to accept an idea with this semantic. > That would probably work well for quite a few drivers that don't want > to ever call clk_get() or clk_prepare_enable() and could tie into the > assigned-clock-rates property in a way that let us keep the platform > details out of the drivers. We could also go one step further and make > a clk pm domain when this new property is present and then have the > clk be enabled based on runtime PM of the device (and if runtime PM is > disabled then just enable it at driver probe time). clk pm domain sounds good, but introducing devm_clk_get_enabled() is much easier and converting to it can be done without dt changes and more or less mechanically. So I consider the cost-usage-value of devm_clk_get_enabled() much better. Best regards Uwe --=20 Pengutronix e.K. | Uwe Kleine-K=F6nig | Industrial Linux Solutions | https://www.pengutronix.de/ | --i6yytbqtmtyzj4jc Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQEzBAABCgAdFiEEfnIqFpAYrP8+dKQLwfwUeK3K7AkFAmEFO0EACgkQwfwUeK3K 7AlP7gf+Mh0OqHPD6Rdp5r9B+Fxlngh7uhJxy6hGORWCzdtQGYt1lJo7givJt/jp h8/E8f7WHUoDRQ1UWeFfpRDlDFxIvLWqw0xCq+V7pSqTzuynRPg8mVGxFvuni+g3 79HyLA6VnVI9rvaSb1NMcWTLwF8FYISAp3WnrpBQnH1VM1Oi/DDGCA+wHGC3XkWI sTqJrqewjSGyanX7ijHA/lGUoC+ibLwy1ilQpRJ99GKfqDvSomtSupY/DocH4euY 7VKDTLKTilOB5f0tFlzYplIjbaphveTAD3Qow91V6ycitCOMqQhu1z3y8cDIQ+x2 iBa83Y+F+FSTBv0yzh0od7me8xfcDA== =D5zi -----END PGP SIGNATURE----- --i6yytbqtmtyzj4jc--