From patchwork Thu Feb 14 10:25:49 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Fabrice Gasnier X-Patchwork-Id: 10812317 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 BAEB313B5 for ; Thu, 14 Feb 2019 10:27:41 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id A70092D2A0 for ; Thu, 14 Feb 2019 10:27:41 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 9B0B72D2BD; Thu, 14 Feb 2019 10:27:41 +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 1677C2D2A0 for ; Thu, 14 Feb 2019 10:27:41 +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=eru+dSbJLOP9UTjGkpoxgKvKh6KbJVaWjJ1Zggecnns=; b=LeLadq2cn3lL4+ izhZRLhlrnkSK3f7vgEPvIJK97NYqjWflnkLZ4sq6k7wOdo2GCI5Hwg0ksaDDy7UT9dU35vB2fYLb /+dFxs6+Ay4vQaB4zhWbkPBegKErSvlF9OKaHhleHV3IsNH+wJZZ/tdlPQpJlrL/6V8+/OD22+kcH yuxoLj8Us+gBEDkL4eAdemA8CRhtXi4o3/ywLU551i1vCZEUekwLMnoiM8OD04Uu2zM0qXPSG8HA4 mqrnPIE2L2Cm6rfbxPAYCWW4jV+0tQmJIlrmDUYgCOBPwRka9bkwI0tGf3v2gpVpoTVxRI5gmPX2h RY93fF6IAzAh25rOWmOA==; 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 1guEF2-00010t-Gp; Thu, 14 Feb 2019 10:27:40 +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 1guEE2-0007q0-1B for linux-arm-kernel@lists.infradead.org; Thu, 14 Feb 2019 10:26:40 +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 x1EAQRKx011458; Thu, 14 Feb 2019 11:26:29 +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 2qmy1na9uu-1 (version=TLSv1 cipher=ECDHE-RSA-AES256-SHA bits=256 verify=NOT); Thu, 14 Feb 2019 11:26:29 +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 6285631; Thu, 14 Feb 2019 10:26:28 +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 F13B54E13; Thu, 14 Feb 2019 10:26:27 +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; Thu, 14 Feb 2019 11:26:27 +0100 From: Fabrice Gasnier To: , Subject: [PATCH v4 1/3] dt-bindings: pwm-stm32-lp: document pinctrl sleep state Date: Thu, 14 Feb 2019 11:25:49 +0100 Message-ID: <1550139951-25788-2-git-send-email-fabrice.gasnier@st.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1550139951-25788-1-git-send-email-fabrice.gasnier@st.com> References: <1550139951-25788-1-git-send-email-fabrice.gasnier@st.com> MIME-Version: 1.0 X-Originating-IP: [10.75.127.47] X-ClientProxiedBy: SFHDAG7NODE1.st.com (10.75.127.19) To SFHDAG5NODE3.st.com (10.75.127.15) X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:, , definitions=2019-02-14_07:, , signatures=0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190214_022638_562154_58BE664A X-CRM114-Status: GOOD ( 10.12 ) 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 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 Thu Feb 14 10:25:50 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Fabrice Gasnier X-Patchwork-Id: 10812321 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 D9AFE922 for ; Thu, 14 Feb 2019 10:28:25 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id C2E062D2A0 for ; Thu, 14 Feb 2019 10:28:25 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id B67B22D2BD; Thu, 14 Feb 2019 10:28:25 +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 611FC2D2A0 for ; Thu, 14 Feb 2019 10:28:25 +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=M5j2IxfesE4BUKr2ezWVkFg8+ZqRV17kJxEzqVFZfCY=; b=rZouW2bfnn4cJz D0pK+YNICFO1Mg5KfJVq1KfjFvcSRyABmHEGMJ1rcnuGo6I4S2b0DLxZte4xNE8B2HzCtcMmd1n0v C1bnEqsomdrJ3qVQQCw8RpdPgq8rPNuaoABm1dLsUFB02ZVQufIunp3v+dnSjMu9NOJCTFXhQPT1g B+dbG3i3fRWXqZ8oj0UwtXWf1oMtU/32rWdFC8M/YNDlnAwQxp4NTd0WT/D1XMwvX2e++83rhawSr VKRGCgyCnE0xxqL/bCg0hxoExARi6L8jLdAGnw637bCvsSy10OaMGM3ouLLeSgd9o2KwacELvhNkn 4jwBCi8vwloKFkMm3CAg==; 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 1guEFe-0001op-Rd; Thu, 14 Feb 2019 10:28:18 +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 1guEE2-0007qh-13 for linux-arm-kernel@lists.infradead.org; Thu, 14 Feb 2019 10:26:43 +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 x1EAQRL1011458; Thu, 14 Feb 2019 11:26:30 +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 2qmy1na9v3-1 (version=TLSv1 cipher=ECDHE-RSA-AES256-SHA bits=256 verify=NOT); Thu, 14 Feb 2019 11:26:30 +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 49F7438; Thu, 14 Feb 2019 10:26:29 +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 19A704E11; Thu, 14 Feb 2019 10:26:29 +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; Thu, 14 Feb 2019 11:26:27 +0100 From: Fabrice Gasnier To: , Subject: [PATCH v4 2/3] pwm: stm32-lp: Add power management support Date: Thu, 14 Feb 2019 11:25:50 +0100 Message-ID: <1550139951-25788-3-git-send-email-fabrice.gasnier@st.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1550139951-25788-1-git-send-email-fabrice.gasnier@st.com> References: <1550139951-25788-1-git-send-email-fabrice.gasnier@st.com> MIME-Version: 1.0 X-Originating-IP: [10.75.127.44] X-ClientProxiedBy: SFHDAG6NODE2.st.com (10.75.127.17) To SFHDAG5NODE3.st.com (10.75.127.15) X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:, , definitions=2019-02-14_07:, , signatures=0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190214_022638_648904_2226D7A3 X-CRM114-Status: GOOD ( 11.75 ) 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 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 int stm32_pwm_lp_remove(struct platform_device *pdev) .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 Thu Feb 14 10:25:51 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Fabrice Gasnier X-Patchwork-Id: 10812319 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 7747B13B5 for ; Thu, 14 Feb 2019 10:28:02 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 641F92D2A0 for ; Thu, 14 Feb 2019 10:28:02 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 57C112D2AC; Thu, 14 Feb 2019 10:28:02 +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 9FF832D2F4 for ; Thu, 14 Feb 2019 10:28:00 +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=Kt3x9JyX64E2tMye0f8A9s6FlnC08tvGRqw88Un1EoE=; b=kHj7Vaa1y8+I+H 1GojaSiGYTgpIt8803sFZ7ZPTmEudxVrCuU77Gh8tvzDETMdNavbWEJolBd3Vf2+cr6tJDTrJTOFy f+eB0KKM1IMKu4fkD1RhaszCHOTaG/tnqrjY06Vp5+4G479DzqwBtPwp4DoW8r9Y/s1f+YskLtiMu LXk2c7pqRp37jjCCV3lQyd8bgtJkikWqFEg1GCK41AVooBMBs39ujHn6Mbpagh+XjWxR8OhlXxg95 5vPwTosVQzWbKgedsfQUEvs0eWNWLGY0TTA8VeaUOI3I2/h1jKjE67ke+Zm6Ag6OZK1xN9wIIiDkQ 1lvxwV8oNXKehQ4sUh2w==; 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 1guEFG-0001GG-Ly; Thu, 14 Feb 2019 10:27:54 +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 1guEE2-0007re-0l for linux-arm-kernel@lists.infradead.org; Thu, 14 Feb 2019 10:26:41 +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 x1EAQTCm032128; Thu, 14 Feb 2019 11:26:30 +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 2qn0jwsvse-1 (version=TLSv1 cipher=ECDHE-RSA-AES256-SHA bits=256 verify=NOT); Thu, 14 Feb 2019 11:26:30 +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 F095731; Thu, 14 Feb 2019 10:26:29 +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 BB8154E10; Thu, 14 Feb 2019 10:26:29 +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; Thu, 14 Feb 2019 11:26:28 +0100 From: Fabrice Gasnier To: , Subject: [PATCH v4 3/3] pwm: core: add consumer device link Date: Thu, 14 Feb 2019 11:25:51 +0100 Message-ID: <1550139951-25788-4-git-send-email-fabrice.gasnier@st.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1550139951-25788-1-git-send-email-fabrice.gasnier@st.com> References: <1550139951-25788-1-git-send-email-fabrice.gasnier@st.com> MIME-Version: 1.0 X-Originating-IP: [10.75.127.44] X-ClientProxiedBy: SFHDAG8NODE2.st.com (10.75.127.23) To SFHDAG5NODE3.st.com (10.75.127.15) X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:, , definitions=2019-02-14_07:, , signatures=0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190214_022638_550994_831771DA X-CRM114-Status: GOOD ( 19.36 ) 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_*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 --- 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..64e10a6 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. + */ + pr_warn("no consumer dev, can't create device link to %s\n", + dev_name(pwm->chip->dev)); + 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);