From patchwork Wed Feb 13 10:50:12 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Fabrice Gasnier X-Patchwork-Id: 10809597 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 51DAE922 for ; Wed, 13 Feb 2019 10:51:16 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 3D3A12CA75 for ; Wed, 13 Feb 2019 10:51:16 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 315A82CA89; Wed, 13 Feb 2019 10:51:16 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.2 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,MAILING_LIST_MULTI,RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id B67F52CA75 for ; Wed, 13 Feb 2019 10:51:15 +0000 (UTC) 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:MIME-Version:References:In-Reply-To: Message-ID:Date:Subject:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=5OlmiPnw4AGzuPKabgT4vKgoXG6bI1eOi39sfdGAGE0=; b=leZX66qQbJAESJ 1FSsmEmNwRYm/28jhKrL2vH8ET7tKweQ2QKFYDM9zvTYeU7/G57OYyhwTsdNSA5byVwRNSAA0cyFI e0PKlTcDbCQetKPgXht8+vmfifOXni9Yhmp2/QiIYW9fa2OhHQyxfaZqdrWG48sX15fhrEXuMdzR5 O8AO2Od0/cnxvvKULJEAN5onD5MOqNJKeB+GBoQG1mLwdV5NZx0JkISLa8PkeB7zAKwkOlyo/4Epx oifBGCdrM/azJrcoajpi/ku5F0rp4KB3Df+d2gp2HYFBOgDb5Pgrq2HwKtkB0Cp72J6padyVs5/F1 rdZVcFsfRNXMk1+q6tfw==; 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 1gts8C-00027E-Nw; Wed, 13 Feb 2019 10:51:08 +0000 Received: from mx08-00178001.pphosted.com ([91.207.212.93] helo=mx07-00178001.pphosted.com) by bombadil.infradead.org with esmtps (Exim 4.90_1 #2 (Red Hat Linux)) id 1gts7o-0001fW-KX for linux-arm-kernel@lists.infradead.org; Wed, 13 Feb 2019 10:50:47 +0000 Received: from pps.filterd (m0046660.ppops.net [127.0.0.1]) by mx08-00178001.pphosted.com (8.16.0.27/8.16.0.27) with SMTP id x1DAg5cj024997; Wed, 13 Feb 2019 11:50:39 +0100 Received: from beta.dmz-eu.st.com (beta.dmz-eu.st.com [164.129.1.35]) by mx08-00178001.pphosted.com with ESMTP id 2qhv0m6nd9-1 (version=TLSv1 cipher=ECDHE-RSA-AES256-SHA bits=256 verify=NOT); Wed, 13 Feb 2019 11:50:39 +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 0F86B31; Wed, 13 Feb 2019 10:50:39 +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 D3E6A4EDF; Wed, 13 Feb 2019 10:50:38 +0000 (GMT) Received: from localhost (10.75.127.48) by SFHDAG5NODE3.st.com (10.75.127.15) with Microsoft SMTP Server (TLS) id 15.0.1347.2; Wed, 13 Feb 2019 11:50:38 +0100 From: Fabrice Gasnier To: , Subject: [PATCH v3 3/3] pwm: core: add consumer device link Date: Wed, 13 Feb 2019 11:50:12 +0100 Message-ID: <1550055012-23348-4-git-send-email-fabrice.gasnier@st.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1550055012-23348-1-git-send-email-fabrice.gasnier@st.com> References: <1550055012-23348-1-git-send-email-fabrice.gasnier@st.com> MIME-Version: 1.0 X-Originating-IP: [10.75.127.48] X-ClientProxiedBy: SFHDAG4NODE3.st.com (10.75.127.12) To SFHDAG5NODE3.st.com (10.75.127.15) X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:, , definitions=2019-02-13_07:, , signatures=0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190213_025044_961095_C09FA8D5 X-CRM114-Status: GOOD ( 17.41 ) 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, linux-pwm@vger.kernel.org, mcoquelin.stm32@gmail.com, u.kleine-koenig@pengutronix.de, fabrice.gasnier@st.com, linux-stm32@st-md-mailman.stormreply.com, linux-arm-kernel@lists.infradead.org Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Virus-Scanned: ClamAV using ClamSMTP 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: - of_pwm_get() - pwm_get() - devm_ variants 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 --- Changes in v3: - add struct device to of_get_pwm() arguments to handle device link from there. --- drivers/pwm/core.c | 14 +++++++++++--- include/linux/pwm.h | 6 ++++-- 2 files changed, 15 insertions(+), 5 deletions(-) diff --git a/drivers/pwm/core.c b/drivers/pwm/core.c index 1581f6a..8cb5d4bc 100644 --- a/drivers/pwm/core.c +++ b/drivers/pwm/core.c @@ -638,6 +638,7 @@ static struct pwm_chip *of_node_to_pwmchip(struct device_node *np) /** * of_pwm_get() - request a PWM via the PWM framework + * @dev: device for PWM consumer * @np: device node to get the PWM from * @con_id: consumer name * @@ -655,7 +656,8 @@ static struct pwm_chip *of_node_to_pwmchip(struct device_node *np) * Returns: A pointer to the requested PWM device or an ERR_PTR()-encoded * error code on failure. */ -struct pwm_device *of_pwm_get(struct device_node *np, const char *con_id) +struct pwm_device *of_pwm_get(struct device *dev, struct device_node *np, + const char *con_id) { struct pwm_device *pwm = NULL; struct of_phandle_args args; @@ -689,6 +691,9 @@ struct pwm_device *of_pwm_get(struct device_node *np, const char *con_id) if (IS_ERR(pwm)) goto put; + if (!device_link_add(dev, pwm->chip->dev, DL_FLAG_AUTOREMOVE_CONSUMER)) + pr_debug("%s(): device link not added\n", __func__); + /* * If a consumer name was not given, try to look it up from the * "pwm-names" property if it exists. Otherwise use the name of @@ -771,7 +776,7 @@ struct pwm_device *pwm_get(struct device *dev, const char *con_id) /* look up via DT first */ if (IS_ENABLED(CONFIG_OF) && dev && dev->of_node) - return of_pwm_get(dev->of_node, con_id); + return of_pwm_get(dev, dev->of_node, con_id); /* * We look up the provider in the static table typically provided by @@ -851,6 +856,9 @@ struct pwm_device *pwm_get(struct device *dev, const char *con_id) pwm->args.period = chosen->period; pwm->args.polarity = chosen->polarity; + if (!device_link_add(dev, pwm->chip->dev, DL_FLAG_AUTOREMOVE_CONSUMER)) + pr_debug("%s(): device link not added\n", __func__); + return pwm; } EXPORT_SYMBOL_GPL(pwm_get); @@ -939,7 +947,7 @@ struct pwm_device *devm_of_pwm_get(struct device *dev, struct device_node *np, if (!ptr) return ERR_PTR(-ENOMEM); - pwm = of_pwm_get(np, con_id); + pwm = of_pwm_get(dev, np, con_id); if (!IS_ERR(pwm)) { *ptr = pwm; devres_add(dev, ptr); diff --git a/include/linux/pwm.h b/include/linux/pwm.h index d5199b5..895e074 100644 --- a/include/linux/pwm.h +++ b/include/linux/pwm.h @@ -406,7 +406,8 @@ struct pwm_device *of_pwm_xlate_with_flags(struct pwm_chip *pc, const struct of_phandle_args *args); struct pwm_device *pwm_get(struct device *dev, const char *con_id); -struct pwm_device *of_pwm_get(struct device_node *np, const char *con_id); +struct pwm_device *of_pwm_get(struct device *dev, struct device_node *np, + const char *con_id); void pwm_put(struct pwm_device *pwm); struct pwm_device *devm_pwm_get(struct device *dev, const char *con_id); @@ -494,7 +495,8 @@ static inline struct pwm_device *pwm_get(struct device *dev, return ERR_PTR(-ENODEV); } -static inline struct pwm_device *of_pwm_get(struct device_node *np, +static inline struct pwm_device *of_pwm_get(struct device *dev, + struct device_node *np, const char *con_id) { return ERR_PTR(-ENODEV);