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=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT 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 6C672C169C4 for ; Mon, 11 Feb 2019 16:13:07 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4600520700 for ; Mon, 11 Feb 2019 16:13:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732269AbfBKQNF (ORCPT ); Mon, 11 Feb 2019 11:13:05 -0500 Received: from mx07-00178001.pphosted.com ([62.209.51.94]:37394 "EHLO mx07-00178001.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727799AbfBKQM7 (ORCPT ); Mon, 11 Feb 2019 11:12:59 -0500 Received: from pps.filterd (m0046037.ppops.net [127.0.0.1]) by mx07-00178001.pphosted.com (8.16.0.27/8.16.0.27) with SMTP id x1BG89Ce026964; Mon, 11 Feb 2019 17:12:46 +0100 Received: from beta.dmz-eu.st.com (beta.dmz-eu.st.com [164.129.1.35]) by mx07-00178001.pphosted.com with ESMTP id 2qhurhu1dh-1 (version=TLSv1 cipher=ECDHE-RSA-AES256-SHA bits=256 verify=NOT); Mon, 11 Feb 2019 17:12:46 +0100 Received: from zeta.dmz-eu.st.com (zeta.dmz-eu.st.com [164.129.230.9]) by beta.dmz-eu.st.com (STMicroelectronics) with ESMTP id ABE2D31; Mon, 11 Feb 2019 16:12:44 +0000 (GMT) Received: from Webmail-eu.st.com (sfhdag5node3.st.com [10.75.127.15]) by zeta.dmz-eu.st.com (STMicroelectronics) with ESMTP id C8E9751C1; Mon, 11 Feb 2019 16:12:43 +0000 (GMT) Received: from localhost (10.75.127.49) by SFHDAG5NODE3.st.com (10.75.127.15) with Microsoft SMTP Server (TLS) id 15.0.1347.2; Mon, 11 Feb 2019 17:12:43 +0100 From: Fabrice Gasnier To: , CC: , , , , , , , , , , Subject: [PATCH v2 3/3] pwm: core: add consumer device link Date: Mon, 11 Feb 2019 17:12:02 +0100 Message-ID: <1549901522-15071-4-git-send-email-fabrice.gasnier@st.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1549901522-15071-1-git-send-email-fabrice.gasnier@st.com> References: <1549901522-15071-1-git-send-email-fabrice.gasnier@st.com> MIME-Version: 1.0 Content-Type: text/plain X-Originating-IP: [10.75.127.49] X-ClientProxiedBy: SFHDAG6NODE1.st.com (10.75.127.16) To SFHDAG5NODE3.st.com (10.75.127.15) X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:,, definitions=2019-02-11_10:,, signatures=0 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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 = 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 = chosen->period; pwm->args.polarity = 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 = pwm; devres_add(dev, ptr); + device_link_add(dev, pwm->chip->dev, + DL_FLAG_AUTOREMOVE_CONSUMER); } else { devres_free(ptr); } -- 1.9.1