From patchwork Wed Feb 20 13:07:46 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Fabrice Gasnier X-Patchwork-Id: 10822135 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 9EE2D6C2 for ; Wed, 20 Feb 2019 13:09:51 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 84D472CF17 for ; Wed, 20 Feb 2019 13:09:51 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 78F082D588; Wed, 20 Feb 2019 13:09:51 +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 2E0932CF17 for ; Wed, 20 Feb 2019 13:09:51 +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=NtgUtWB61/zwmYta8Ouel6LrFQDB6yhp1Q/Gi2gMBQo=; b=mVAlNwKnXs98jK TKupBu2ZG65jBRuxnq02Trovz9i/Ir0BZgF58g9hXY0/xIcs2cSQscKepbF37h/5h7XWiYpxjUJla ZQZiGX6Z+Zul6zzN+TDz1SRTDwY0bGOTSWOZ7FVd3oeUt4Cuh7fnmwPRgORJL7WGci4mhqlOPM09i PHlI29rNSnS7YXbzNSa5VOCC77Szo5JafTW5Ryc0TFRT6kd5GH8BaUzOpjYohGmZ69+zNZb3pG/Y1 pJ+IltC0VGVd5vQdWhkgUiFZzXD4bx3qegTVO3p0q5coDL+inMXfFobRcMMx+7k/h58pnq0/w541/ /ZK0JcZMaQUUEr7sM4gg==; 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 1gwRd8-0006YF-7K; Wed, 20 Feb 2019 13:09:42 +0000 Received: from mx07-00178001.pphosted.com ([62.209.51.94]) by bombadil.infradead.org with esmtps (Exim 4.90_1 #2 (Red Hat Linux)) id 1gwRcl-00068P-LO for linux-arm-kernel@lists.infradead.org; Wed, 20 Feb 2019 13:09:22 +0000 Received: from pps.filterd (m0046668.ppops.net [127.0.0.1]) by mx07-00178001.pphosted.com (8.16.0.27/8.16.0.27) with SMTP id x1KD6Yfi018759; Wed, 20 Feb 2019 14:09:09 +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 2qr6x5s9fa-1 (version=TLSv1 cipher=ECDHE-RSA-AES256-SHA bits=256 verify=NOT); Wed, 20 Feb 2019 14:09:09 +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 7F56E34; Wed, 20 Feb 2019 13:09:08 +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 487AD2BB6; Wed, 20 Feb 2019 13:09:08 +0000 (GMT) Received: from localhost (10.75.127.44) by SFHDAG5NODE3.st.com (10.75.127.15) with Microsoft SMTP Server (TLS) id 15.0.1347.2; Wed, 20 Feb 2019 14:09:07 +0100 From: Fabrice Gasnier To: Subject: [PATCH v5 1/3] dt-bindings: pwm-stm32-lp: document pinctrl sleep state Date: Wed, 20 Feb 2019 14:07:46 +0100 Message-ID: <1550668068-9661-2-git-send-email-fabrice.gasnier@st.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1550668068-9661-1-git-send-email-fabrice.gasnier@st.com> References: <1550668068-9661-1-git-send-email-fabrice.gasnier@st.com> MIME-Version: 1.0 X-Originating-IP: [10.75.127.44] X-ClientProxiedBy: SFHDAG4NODE2.st.com (10.75.127.11) To SFHDAG5NODE3.st.com (10.75.127.15) X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:, , definitions=2019-02-20_11:, , signatures=0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190220_050919_994278_415ADF0F X-CRM114-Status: GOOD ( 10.37 ) 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, robh+dt@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 documentation for pinctrl sleep state on STM32 LPTimer PWM. Signed-off-by: Fabrice Gasnier Reviewed-by: Rob Herring --- Documentation/devicetree/bindings/pwm/pwm-stm32-lp.txt | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/Documentation/devicetree/bindings/pwm/pwm-stm32-lp.txt b/Documentation/devicetree/bindings/pwm/pwm-stm32-lp.txt index bd23302..6521bc4 100644 --- a/Documentation/devicetree/bindings/pwm/pwm-stm32-lp.txt +++ b/Documentation/devicetree/bindings/pwm/pwm-stm32-lp.txt @@ -11,8 +11,10 @@ Required parameters: bindings defined in pwm.txt. Optional properties: -- pinctrl-names: Set to "default". -- pinctrl-0: Phandle pointing to pin configuration node for PWM. +- pinctrl-names: Set to "default". An additional "sleep" state can be + defined to set pins in sleep state when in low power. +- pinctrl-n: Phandle(s) pointing to pin configuration node for PWM, + respectively for "default" and "sleep" states. Example: timer@40002400 { @@ -21,7 +23,8 @@ Example: pwm { compatible = "st,stm32-pwm-lp"; #pwm-cells = <3>; - pinctrl-names = "default"; + pinctrl-names = "default", "sleep"; pinctrl-0 = <&lppwm1_pins>; + pinctrl-1 = <&lppwm1_sleep_pins>; }; }; From patchwork Wed Feb 20 13:07:47 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Fabrice Gasnier X-Patchwork-Id: 10822133 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 6DF4A6C2 for ; Wed, 20 Feb 2019 13:09:34 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 50CD32CF17 for ; Wed, 20 Feb 2019 13:09:34 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 423092D588; Wed, 20 Feb 2019 13:09:34 +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 DEA9A2CF17 for ; Wed, 20 Feb 2019 13:09:33 +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=vXBQ/SFNrYFcxo+mJVIaAGYZCbGfTqnNzHeeWYYZD2o=; b=BfDKm80w+nYywZ rmq4Rc34tHY8WzZ9cC/1g8Gc8aax31CZ6WgOpnk+QG9zVEkcoIv9L2jtfthqU+84OYeycoIiu4KSW Nbeybl9QNnWbrH3VNsxX5jfb9AhS0lVKthCsP0gxqL+6UgJMWgiXFE34h/9bg4JQlf8b7r/eJHM16 zm/mssV3jwBjKsdZtwOatwv+Yuc9hVXrwb5HKdnjISg6IpL+DmRZSbbkPE32EVF5yWhws/3ngdjJE ltcjo1Gc7MkZcPzMK4y8NtVwKvE81TnOfxfi4SYlka66oj/m59T4EFnldE5P/ewniyXkFxJsbKCdV S3ewFadAtQSQlISXCZRA==; 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 1gwRcy-0006Kn-NC; Wed, 20 Feb 2019 13:09:32 +0000 Received: from mx07-00178001.pphosted.com ([62.209.51.94]) by bombadil.infradead.org with esmtps (Exim 4.90_1 #2 (Red Hat Linux)) id 1gwRcl-00068R-LW for linux-arm-kernel@lists.infradead.org; Wed, 20 Feb 2019 13:09:23 +0000 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 x1KD6P7V019598; Wed, 20 Feb 2019 14:09:10 +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 2qpc6kwn65-1 (version=TLSv1 cipher=ECDHE-RSA-AES256-SHA bits=256 verify=NOT); Wed, 20 Feb 2019 14:09:10 +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 42DC431; Wed, 20 Feb 2019 13:09:09 +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 27AD32BB4; Wed, 20 Feb 2019 13:09:09 +0000 (GMT) Received: from localhost (10.75.127.44) by SFHDAG5NODE3.st.com (10.75.127.15) with Microsoft SMTP Server (TLS) id 15.0.1347.2; Wed, 20 Feb 2019 14:09:08 +0100 From: Fabrice Gasnier To: Subject: [PATCH v5 2/3] pwm: stm32-lp: Add power management support Date: Wed, 20 Feb 2019 14:07:47 +0100 Message-ID: <1550668068-9661-3-git-send-email-fabrice.gasnier@st.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1550668068-9661-1-git-send-email-fabrice.gasnier@st.com> References: <1550668068-9661-1-git-send-email-fabrice.gasnier@st.com> MIME-Version: 1.0 X-Originating-IP: [10.75.127.44] X-ClientProxiedBy: SFHDAG3NODE1.st.com (10.75.127.7) To SFHDAG5NODE3.st.com (10.75.127.15) X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:, , definitions=2019-02-20_11:, , signatures=0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190220_050920_010991_8C586454 X-CRM114-Status: GOOD ( 12.32 ) 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, robh+dt@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 suspend/resume PM sleep ops. When going to low power, enforce the PWM channel isn't active. Let the PWM consumers disable it during their own suspend sequence. Only perform a check here, and handle the pinctrl states. See [1]. [1] https://lkml.org/lkml/2019/2/5/770 Signed-off-by: Fabrice Gasnier --- Changes in v2: - Don't disable PWM channel: let the PWM user disable it. Refuse to suspend in case it's been left enabled. - Drop the ifdefs, use __maybe_unused instead. --- drivers/pwm/pwm-stm32-lp.c | 25 +++++++++++++++++++++++++ 1 file changed, 25 insertions(+) diff --git a/drivers/pwm/pwm-stm32-lp.c b/drivers/pwm/pwm-stm32-lp.c index 0059b24c..2211a64 100644 --- a/drivers/pwm/pwm-stm32-lp.c +++ b/drivers/pwm/pwm-stm32-lp.c @@ -13,6 +13,7 @@ #include #include #include +#include #include #include @@ -223,6 +224,29 @@ static int stm32_pwm_lp_remove(struct platform_device *pdev) return pwmchip_remove(&priv->chip); } +static int __maybe_unused stm32_pwm_lp_suspend(struct device *dev) +{ + struct stm32_pwm_lp *priv = dev_get_drvdata(dev); + struct pwm_state state; + + pwm_get_state(&priv->chip.pwms[0], &state); + if (state.enabled) { + dev_err(dev, "The consumer didn't stop us (%s)\n", + priv->chip.pwms[0].label); + return -EBUSY; + } + + return pinctrl_pm_select_sleep_state(dev); +} + +static int __maybe_unused stm32_pwm_lp_resume(struct device *dev) +{ + return pinctrl_pm_select_default_state(dev); +} + +static SIMPLE_DEV_PM_OPS(stm32_pwm_lp_pm_ops, stm32_pwm_lp_suspend, + stm32_pwm_lp_resume); + static const struct of_device_id stm32_pwm_lp_of_match[] = { { .compatible = "st,stm32-pwm-lp", }, {}, @@ -235,6 +259,7 @@ static struct platform_driver stm32_pwm_lp_driver = { .driver = { .name = "stm32-pwm-lp", .of_match_table = of_match_ptr(stm32_pwm_lp_of_match), + .pm = &stm32_pwm_lp_pm_ops, }, }; module_platform_driver(stm32_pwm_lp_driver); From patchwork Wed Feb 20 13:07:48 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Fabrice Gasnier X-Patchwork-Id: 10822137 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 DB20C6C2 for ; Wed, 20 Feb 2019 13:09:56 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id BED5A2CF17 for ; Wed, 20 Feb 2019 13:09:56 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id B1B952D588; Wed, 20 Feb 2019 13:09:56 +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 340BD2CF17 for ; Wed, 20 Feb 2019 13:09:56 +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=7KnQq2R5hk31TTxhuhYJ2jTsticUMl3uNuUZFbMYsRQ=; b=P/I8OsMfcv0Hti o90u87QlvsIZpUkhie+79cwFn3IYxpedPSG0m11sg3Fzfr4JXUNIXAyTObWiYDMClNTBOZu7u60YS prLJAQXbzhvBDPLu5u1fjktlJuIBmXdY/AgyObw7NMnq5NCwphWdO2kcZGVyJsZ7S3hL3m4qvofWk j3sFKK68wSqqV5ZFgnflIu1pj1id1isEQ47ILr8PIFYcpim5xEW+LktRA/UWvXdraP4WvOwE5QBid jV5NIna+VK9qIigf1HIwa8awDU37r+s7xAWTCsoKs8+fSoTafoU9zpWzKcMCmyFWiks5ZRM0v9hiK TqBTnJxNLhQFafiiNVcw==; 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 1gwRdJ-0006oe-8Z; Wed, 20 Feb 2019 13:09:53 +0000 Received: from mx07-00178001.pphosted.com ([62.209.51.94]) by bombadil.infradead.org with esmtps (Exim 4.90_1 #2 (Red Hat Linux)) id 1gwRcl-00068Q-Gp for linux-arm-kernel@lists.infradead.org; Wed, 20 Feb 2019 13:09:25 +0000 Received: from pps.filterd (m0046668.ppops.net [127.0.0.1]) by mx07-00178001.pphosted.com (8.16.0.27/8.16.0.27) with SMTP id x1KD6Mpa018722; Wed, 20 Feb 2019 14:09:10 +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 2qr6x5s9fh-1 (version=TLSv1 cipher=ECDHE-RSA-AES256-SHA bits=256 verify=NOT); Wed, 20 Feb 2019 14:09:10 +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 1AEE334; Wed, 20 Feb 2019 13:09:10 +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 E843F2BB4; Wed, 20 Feb 2019 13:09:09 +0000 (GMT) Received: from localhost (10.75.127.47) by SFHDAG5NODE3.st.com (10.75.127.15) with Microsoft SMTP Server (TLS) id 15.0.1347.2; Wed, 20 Feb 2019 14:09:09 +0100 From: Fabrice Gasnier To: Subject: [PATCH v5 3/3] pwm: core: add consumer device link Date: Wed, 20 Feb 2019 14:07:48 +0100 Message-ID: <1550668068-9661-4-git-send-email-fabrice.gasnier@st.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1550668068-9661-1-git-send-email-fabrice.gasnier@st.com> References: <1550668068-9661-1-git-send-email-fabrice.gasnier@st.com> MIME-Version: 1.0 X-Originating-IP: [10.75.127.47] X-ClientProxiedBy: SFHDAG3NODE1.st.com (10.75.127.7) To SFHDAG5NODE3.st.com (10.75.127.15) X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:, , definitions=2019-02-20_11:, , signatures=0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190220_050919_848291_E1DEEAF3 X-CRM114-Status: GOOD ( 19.89 ) 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, robh+dt@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_*pwm_get() 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 Acked-by: Uwe Kleine-König --- Changes in v5: - fix a style issue - use dev_warn() instead of pr_warn Changes in v4: - rework error handling following Thierry's comments - turn/split pr_debug() into dev_err()/pr_warn(). Changes in v3: - add struct device to of_get_pwm() arguments to handle device link from there as discussed with Uwe. --- drivers/pwm/core.c | 50 +++++++++++++++++++++++++++++++++++++++++++++++--- include/linux/pwm.h | 6 ++++-- 2 files changed, 51 insertions(+), 5 deletions(-) diff --git a/drivers/pwm/core.c b/drivers/pwm/core.c index 1581f6a..03aa1b5 100644 --- a/drivers/pwm/core.c +++ b/drivers/pwm/core.c @@ -636,8 +636,35 @@ static struct pwm_chip *of_node_to_pwmchip(struct device_node *np) return ERR_PTR(-EPROBE_DEFER); } +static struct device_link *pwm_device_link_add(struct device *dev, + struct pwm_device *pwm) +{ + struct device_link *dl; + + if (!dev) { + /* + * No device for the PWM consumer has been provided. It may + * impact the PM sequence ordering: the PWM supplier may get + * suspended before the consumer. + */ + dev_warn(pwm->chip->dev, + "No consumer device specified to create a link to\n"); + return NULL; + } + + dl = device_link_add(dev, pwm->chip->dev, DL_FLAG_AUTOREMOVE_CONSUMER); + if (!dl) { + dev_err(dev, "failed to create device link to %s\n", + dev_name(pwm->chip->dev)); + return ERR_PTR(-EINVAL); + } + + return dl; +} + /** * 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 * @@ -655,10 +682,12 @@ 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; + struct device_link *dl; struct pwm_chip *pc; int index = 0; int err; @@ -689,6 +718,14 @@ struct pwm_device *of_pwm_get(struct device_node *np, const char *con_id) if (IS_ERR(pwm)) goto put; + dl = pwm_device_link_add(dev, pwm); + if (IS_ERR(dl)) { + /* of_xlate ended up calling pwm_request_from_chip() */ + pwm_free(pwm); + pwm = ERR_CAST(dl); + goto put; + } + /* * 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 @@ -764,6 +801,7 @@ struct pwm_device *pwm_get(struct device *dev, const char *con_id) const char *dev_id = dev ? dev_name(dev) : NULL; struct pwm_device *pwm; struct pwm_chip *chip; + struct device_link *dl; unsigned int best = 0; struct pwm_lookup *p, *chosen = NULL; unsigned int match; @@ -771,7 +809,7 @@ 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 @@ -848,6 +886,12 @@ struct pwm_device *pwm_get(struct device *dev, const char *con_id) if (IS_ERR(pwm)) return pwm; + dl = pwm_device_link_add(dev, pwm); + if (IS_ERR(dl)) { + pwm_free(pwm); + return ERR_CAST(dl); + } + pwm->args.period = chosen->period; pwm->args.polarity = chosen->polarity; @@ -939,7 +983,7 @@ 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);