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=-9.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_PASS,USER_AGENT_NEOMUTT autolearn=ham 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 C674FC169C4 for ; Mon, 11 Feb 2019 19:06:55 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id 95AC421B68 for ; Mon, 11 Feb 2019 19:06:55 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="P5kBgwkK" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 95AC421B68 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=pengutronix.de Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=UbpB5j3mZNwwyiMZeC23UI/4PK+NwsHQZUv2CPtizy8=; b=P5kBgwkKMd7M+c XEIpXbAeHHv7bPtRmW5NbSi+ziiJ41g+9zC4DMMYwJkhm8k7LWBGPKDQrZunyaB6qVKfj9Vl7kq7a SHJB6b/NF5LtmIuzo3zpO9IXwYKYyUA6aJNZkVhSUIVVNGrU0nxD7Tf1rnQZq2Y/dlzToy8tHhvJK KlDt6jad4NzyvN+C/e8FS2cidNMDSw8lEu24/Ei4M64zNL67YA4rEbxoQSgEsKaltj0WbEP87XZI0 tgAh/ttDsapK4aASLyXU0xVSl7EEAtjTa7iEfxd2csnamTa8T/ltd3puKv4pnrxYj7/67WncDewYQ FpJ8edn5kokiGdjcitjQ==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1gtGuk-0004yP-Ui; Mon, 11 Feb 2019 19:06:46 +0000 Received: from metis.ext.pengutronix.de ([2001:67c:670:201:290:27ff:fe1d:cc33]) by bombadil.infradead.org with esmtps (Exim 4.90_1 #2 (Red Hat Linux)) id 1gtGub-0004x0-JF for linux-arm-kernel@lists.infradead.org; Mon, 11 Feb 2019 19:06:44 +0000 Received: from pty.hi.pengutronix.de ([2001:67c:670:100:1d::c5]) by metis.ext.pengutronix.de with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.89) (envelope-from ) id 1gtGuU-00066d-Ph; Mon, 11 Feb 2019 20:06:30 +0100 Received: from ukl by pty.hi.pengutronix.de with local (Exim 4.89) (envelope-from ) id 1gtGuS-0007sp-If; Mon, 11 Feb 2019 20:06:28 +0100 Date: Mon, 11 Feb 2019 20:06:28 +0100 From: Uwe =?iso-8859-1?Q?Kleine-K=F6nig?= To: Fabrice Gasnier Subject: Re: [PATCH v2 3/3] pwm: core: add consumer device link Message-ID: <20190211190628.eisyi6wjus4ltrrn@pengutronix.de> References: <1549901522-15071-1-git-send-email-fabrice.gasnier@st.com> <1549901522-15071-4-git-send-email-fabrice.gasnier@st.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <1549901522-15071-4-git-send-email-fabrice.gasnier@st.com> User-Agent: NeoMutt/20170113 (1.7.2) X-SA-Exim-Connect-IP: 2001:67c:670:100:1d::c5 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-arm-kernel@lists.infradead.org X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190211_110637_791436_414B7DEE X-CRM114-Status: GOOD ( 16.54 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: mark.rutland@arm.com, devicetree@vger.kernel.org, alexandre.torgue@st.com, tduszyns@gmail.com, linux-kernel@vger.kernel.org, robh+dt@kernel.org, thierry.reding@gmail.com, linux-pwm@vger.kernel.org, mcoquelin.stm32@gmail.com, linux-stm32@st-md-mailman.stormreply.com, linux-arm-kernel@lists.infradead.org Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org Hello Fabrice, On Mon, Feb 11, 2019 at 05:12:02PM +0100, Fabrice Gasnier wrote: > Add a device link between the PWM consumer and the PWM provider. This > enforces the PWM user to get suspended before the PWM provider. It > allows proper synchronization of suspend/resume sequences: the PWM user > is responsible for properly stopping PWM, before the provider gets > suspended: see [1]. Add the device link in: > - pwm_get() > - devm_pwm_get() > - devm_of_pwm_get() > as it requires a reference to the device for the PWM consumer. > = > [1] https://lkml.org/lkml/2019/2/5/770 > = > Suggested-by: Thierry Reding > Signed-off-by: Fabrice Gasnier > --- > drivers/pwm/core.c | 13 +++++++++++-- > 1 file changed, 11 insertions(+), 2 deletions(-) > = > diff --git a/drivers/pwm/core.c b/drivers/pwm/core.c > index 1581f6a..2835e27 100644 > --- a/drivers/pwm/core.c > +++ b/drivers/pwm/core.c > @@ -770,8 +770,13 @@ struct pwm_device *pwm_get(struct device *dev, const= char *con_id) > int err; > = > /* look up via DT first */ > - if (IS_ENABLED(CONFIG_OF) && dev && dev->of_node) > - return of_pwm_get(dev->of_node, con_id); > + if (IS_ENABLED(CONFIG_OF) && dev && dev->of_node) { > + pwm =3D of_pwm_get(dev->of_node, con_id); > + if (!IS_ERR(pwm)) > + device_link_add(dev, pwm->chip->dev, > + DL_FLAG_AUTOREMOVE_CONSUMER); > + return pwm; > + } > = > /* > * We look up the provider in the static table typically provided by > @@ -851,6 +856,8 @@ struct pwm_device *pwm_get(struct device *dev, const = char *con_id) > pwm->args.period =3D chosen->period; > pwm->args.polarity =3D chosen->polarity; > = > + device_link_add(dev, pwm->chip->dev, DL_FLAG_AUTOREMOVE_CONSUMER); > + > return pwm; > } > EXPORT_SYMBOL_GPL(pwm_get); > @@ -943,6 +950,8 @@ struct pwm_device *devm_of_pwm_get(struct device *dev= , struct device_node *np, > if (!IS_ERR(pwm)) { > *ptr =3D pwm; > devres_add(dev, ptr); > + device_link_add(dev, pwm->chip->dev, > + DL_FLAG_AUTOREMOVE_CONSUMER); IMHO it's surprising that devm_of_pwm_get() does more than of_pwm_get() + devres stuff. I'd put device_link_add() into of_pwm_get(). Best regards Uwe -- = Pengutronix e.K. | Uwe Kleine-K=F6nig | Industrial Linux Solutions | http://www.pengutronix.de/ | _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel