From patchwork Thu Oct 22 03:23:24 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chen Yu X-Patchwork-Id: 11850183 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 2F7B41580 for ; Thu, 22 Oct 2020 03:21:39 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1352221534 for ; Thu, 22 Oct 2020 03:21:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2895321AbgJVDVi (ORCPT ); Wed, 21 Oct 2020 23:21:38 -0400 Received: from mga02.intel.com ([134.134.136.20]:7623 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2443456AbgJVDVi (ORCPT ); Wed, 21 Oct 2020 23:21:38 -0400 IronPort-SDR: 9ph1gteUXu2hpeelS5YSlshI3jECgdkZENqL9h0iMtgyU7MfdVmUgHyfdh82/+0x7k+ty3E29E DBa1mR6zXIqg== X-IronPort-AV: E=McAfee;i="6000,8403,9781"; a="154418920" X-IronPort-AV: E=Sophos;i="5.77,403,1596524400"; d="scan'208";a="154418920" X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga008.fm.intel.com ([10.253.24.58]) by orsmga101.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 21 Oct 2020 20:21:37 -0700 IronPort-SDR: zVq9ZMmOMBwT1s+CtuqYsuoILt9sZOJdDNBiF4scm8qMmDbyRHIhtys6CJz6iXMwHUACl+8gy+ 73Hppwtn9ExA== X-IronPort-AV: E=Sophos;i="5.77,403,1596524400"; d="scan'208";a="302212891" Received: from chenyu-office.sh.intel.com ([10.239.158.173]) by fmsmga008-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 21 Oct 2020 20:21:35 -0700 From: Chen Yu To: "Rafael J. Wysocki" , Len Brown Cc: Andy Shevchenko , Greg Kroah-Hartman , linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org, Chen Yu Subject: [PATCH] PM / sysfs: Expose suspend resume driver flags in sysfs Date: Thu, 22 Oct 2020 11:23:24 +0800 Message-Id: <20201022032324.25308-1-yu.c.chen@intel.com> X-Mailer: git-send-email 2.17.1 Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org Currently there are 4 driver flags to control system suspend/resume behavior: DPM_FLAG_NO_DIRECT_COMPLETE, DPM_FLAG_SMART_PREPARE, DPM_FLAG_SMART_SUSPEND and DPM_FLAG_MAY_SKIP_RESUME. Make these flags visible in sysfs as read-only to get a brief understanding of the expected behavior of each device during suspend/resume, so as to facilitate suspend/resume debugging/tuning. For example: /sys/devices/pci0000:00/0000:00:15.1/power/driver_flags:4 (DPM_FLAG_SMART_SUSPEND) /sys/devices/pci0000:00/0000:00:07.3/power/driver_flags:5 (DPM_FLAG_NO_DIRECT_COMPLETE | DPM_FLAG_SMART_SUSPEND) Acked-by: Len Brown Signed-off-by: Chen Yu --- drivers/base/power/sysfs.c | 29 ++++++++++++++++++++++++++++- 1 file changed, 28 insertions(+), 1 deletion(-) diff --git a/drivers/base/power/sysfs.c b/drivers/base/power/sysfs.c index a1474fb67db9..48313a1040a5 100644 --- a/drivers/base/power/sysfs.c +++ b/drivers/base/power/sysfs.c @@ -607,6 +607,13 @@ static ssize_t async_store(struct device *dev, struct device_attribute *attr, static DEVICE_ATTR_RW(async); +static ssize_t driver_flags_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + return sysfs_emit(buf, "%x\n", dev->power.driver_flags); +} +static DEVICE_ATTR_RO(driver_flags); + #endif /* CONFIG_PM_SLEEP */ #endif /* CONFIG_PM_ADVANCED_DEBUG */ @@ -691,6 +698,20 @@ static const struct attribute_group pm_qos_flags_attr_group = { .attrs = pm_qos_flags_attrs, }; +static struct attribute *pm_driver_flags_attrs[] = { +#ifdef CONFIG_PM_ADVANCED_DEBUG +#ifdef CONFIG_PM_SLEEP + &dev_attr_driver_flags.attr, +#endif +#endif + NULL, +}; + +static const struct attribute_group pm_driver_flags_attr_group = { + .name = power_group_name, + .attrs = pm_driver_flags_attrs, +}; + int dpm_sysfs_add(struct device *dev) { int rc; @@ -719,11 +740,17 @@ int dpm_sysfs_add(struct device *dev) if (rc) goto err_wakeup; } - rc = pm_wakeup_source_sysfs_add(dev); + rc = sysfs_merge_group(&dev->kobj, &pm_driver_flags_attr_group); if (rc) goto err_latency; + + rc = pm_wakeup_source_sysfs_add(dev); + if (rc) + goto err_flags; return 0; + err_flags: + sysfs_unmerge_group(&dev->kobj, &pm_driver_flags_attr_group); err_latency: sysfs_unmerge_group(&dev->kobj, &pm_qos_latency_tolerance_attr_group); err_wakeup: