From patchwork Sat May 30 16:33:33 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Heiner Kallweit X-Patchwork-Id: 11580495 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id AEAFD739 for ; Sat, 30 May 2020 16:33:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8A59A2081A for ; Sat, 30 May 2020 16:33:43 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="er6kemQP" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729133AbgE3Qdm (ORCPT ); Sat, 30 May 2020 12:33:42 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58140 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728927AbgE3Qdm (ORCPT ); Sat, 30 May 2020 12:33:42 -0400 Received: from mail-ej1-x641.google.com (mail-ej1-x641.google.com [IPv6:2a00:1450:4864:20::641]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 395A5C03E969; Sat, 30 May 2020 09:33:42 -0700 (PDT) Received: by mail-ej1-x641.google.com with SMTP id x1so5116840ejd.8; Sat, 30 May 2020 09:33:42 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:subject:to:cc:message-id:date:user-agent:mime-version :content-language:content-transfer-encoding; bh=KnghmerSNdwoxGexYivjS5o548htuxNSrbhg+RVRtPQ=; b=er6kemQP2Y+MzHzHZ6ORCyJ9vb1OE6uFyoA2okXI7qTG75+1L0Vnkzvtts0aVlb9zL fkmJxEzxXIKXf1dF1CZnjdrn2VjpeM4qE8XR+fb314nrzpKRgJTeV4UR4lDlkxvJLVM7 OBW2UhrkdG1RluWyQAtwLuU3t48IboIl1W/RNob5Kdjo1jgAvjFBDO48PemxgjvyF1rZ gFOfdWCKcdgnk7k3YVVxPGZS92jxjiylqFQUOBA8F9LsRws0zlKgdZA1RtitcUJwSXgC N1IdP3YKOK2VxutVGp01G5x5bF/I4Uc8OwDIb6EHm56t3Peaix8mg9n1xCUZJgoAWXLd nJVQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:subject:to:cc:message-id:date:user-agent :mime-version:content-language:content-transfer-encoding; bh=KnghmerSNdwoxGexYivjS5o548htuxNSrbhg+RVRtPQ=; b=JosgYOvICUdKdXLM2F5MZYT4u7ExdOc8fvN/gE89osmkUuYPQGsgva8l+DRyDGS3f2 4De5snt/JgbHRku1ekV3oM6DWNdveaui4ZpjegLJ/AvXge7ezpTXRFCiTFFN0QDntFQz xlYxlJYZEleEUu7fkkVozX+mESWzpcJETPmPswol1iTi3NuUilHj98/M/yj5oU3Tj0OD 8757Bv661ZkPoM3JKgTjsmTyCdJ6uYhx+lgsU7qofLWltwarj8Gk5ROIhEvCCJZhASpB 5/PEXF6O4GrjY9x9X5S+LE5vxIGAP6n5UtvI33CY6HjqMXLb4Aj+ongstJ4wFHjx/L2H S3hg== X-Gm-Message-State: AOAM530cxaAtyl8Ij9QRs1muRXiGOidK5E7/IBbGvmXj73+6tCi5//Zw QsZSYfjBDc93Xdoy500N4uq3Vq7g X-Google-Smtp-Source: ABdhPJz7Rpf0OLy1MxXwnNbI9BzsI4rayT0P5TXJKfzVinlbJpTcf36wPBgioNd8W07VmIUwCWsMTQ== X-Received: by 2002:a17:906:1442:: with SMTP id q2mr12064078ejc.33.1590856420605; Sat, 30 May 2020 09:33:40 -0700 (PDT) Received: from ?IPv6:2003:ea:8f23:5700:9c9f:9224:f2fc:26c2? (p200300ea8f2357009c9f9224f2fc26c2.dip0.t-ipconnect.de. [2003:ea:8f23:5700:9c9f:9224:f2fc:26c2]) by smtp.googlemail.com with ESMTPSA id b15sm10685016edj.37.2020.05.30.09.33.39 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Sat, 30 May 2020 09:33:40 -0700 (PDT) From: Heiner Kallweit Subject: [PATCH] PM: runtime: add RPM_IDLE_SUSPEND / RPM_IDLE_NO_SUSPEND constants To: "Rafael J. Wysocki" , Pavel Machek , Len Brown , Greg Kroah-Hartman Cc: Linux PM , Linux Kernel Mailing List Message-ID: <94fe944c-c528-9459-fc75-7c94273dd2b1@gmail.com> Date: Sat, 30 May 2020 18:33:33 +0200 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:68.0) Gecko/20100101 Thunderbird/68.8.1 MIME-Version: 1.0 Content-Language: en-US Sender: linux-pm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org runtime_idle() callback implementations have to return a non-zero value if they don't intend to suspend now. Several drivers use an errno like -EBUSY for this purpose. This can be problematic because the return value is propagated up the call chain, from rpm_idle() to __pm_runtime_idle(), and from there to callers like pm_runtime_put_sync(). A driver author checking the return value of e.g. pm_runtime_put_sync() may as usual check for retval < 0 and bail out. Therefore a positive value should be returned. To facilitate this add constants RPM_IDLE_SUSPEND and RPM_IDLE_NO_SUSPEND. Signed-off-by: Heiner Kallweit --- drivers/base/power/runtime.c | 6 +++++- include/linux/pm.h | 10 ++++++++-- 2 files changed, 13 insertions(+), 3 deletions(-) diff --git a/drivers/base/power/runtime.c b/drivers/base/power/runtime.c index 9f62790f6..4f529075e 100644 --- a/drivers/base/power/runtime.c +++ b/drivers/base/power/runtime.c @@ -453,7 +453,11 @@ static int rpm_idle(struct device *dev, int rpmflags) out: trace_rpm_return_int_rcuidle(dev, _THIS_IP_, retval); - return retval ? retval : rpm_suspend(dev, rpmflags | RPM_AUTO); + + if (retval == RPM_IDLE_SUSPEND) + return rpm_suspend(dev, rpmflags | RPM_AUTO); + + return retval; } /** diff --git a/include/linux/pm.h b/include/linux/pm.h index 121c104a4..971ed3d77 100644 --- a/include/linux/pm.h +++ b/include/linux/pm.h @@ -227,8 +227,9 @@ typedef struct pm_message { * * @runtime_idle: Device appears to be inactive and it might be put into a * low-power state if all of the necessary conditions are satisfied. - * Check these conditions, and return 0 if it's appropriate to let the PM - * core queue a suspend request for the device. + * Check these conditions, and return RPM_IDLE_SUSPEND if it's + * appropriate to let the PM core queue a suspend request for the device. + * Return RPM_IDLE_NO_SUSPEND if you don't want to suspend now. * * Several device power state transitions are externally visible, affecting * the state of pending I/O queues and (for drivers that touch hardware) @@ -523,6 +524,11 @@ enum rpm_request { RPM_REQ_RESUME, }; +enum rpm_idle { + RPM_IDLE_SUSPEND = 0, + RPM_IDLE_NO_SUSPEND, +}; + struct wakeup_source; struct wake_irq; struct pm_domain_data;