Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S936459AbcKXAd2 (ORCPT ); Wed, 23 Nov 2016 19:33:28 -0500 Received: from smtp.codeaurora.org ([198.145.29.96]:51914 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934917AbcKXAdY (ORCPT ); Wed, 23 Nov 2016 19:33:24 -0500 DMARC-Filter: OpenDMARC Filter v1.3.1 smtp.codeaurora.org BAA95614A1 Authentication-Results: pdx-caf-mail.web.codeaurora.org; dmarc=none header.from=codeaurora.org Authentication-Results: pdx-caf-mail.web.codeaurora.org; spf=pass smtp.mailfrom=subhashj@codeaurora.org From: Subhash Jadavani To: vinholikatti@gmail.com, jejb@linux.vnet.ibm.com, martin.petersen@oracle.com Cc: Subhash Jadavani , linux-scsi@vger.kernel.org (open list:UNIVERSAL FLASH STORAGE HOST CONTROLLER DRIVER), linux-kernel@vger.kernel.org (open list) Subject: [PATCH v1 10/11] scsi: ufs: optimize system suspend handling Date: Wed, 23 Nov 2016 16:33:08 -0800 Message-Id: <1479947588-7297-1-git-send-email-subhashj@codeaurora.org> X-Mailer: git-send-email 1.9.1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2248 Lines: 52 Consider following sequence of events: 1. UFS is runtime suspended, link_state = Hibern8, device_state = sleep 2. System goes into system suspend, ufshcd_system_suspend() brings both link and device to active state and then puts the device in Power_Down state and link in OFF state. 3. System resumes at some later point in time, ufshcd_system_resume() doesn't do anything as UFS state is runtime suspended. Note that link is still on OFF state and device is in Power_Down state. 4. Now system again goes into suspend without any UFS accesses before it. ufshcd_system_suspend() again brings both link and device to active state and then puts the device in Power_Down state and link if OFF state. But it's unnecessary to bring the link & device in active state as both link and device are already in desired low power states. This change fixes this issue by adding proper state checks in ufshcd_system_suspend(). Reviewed-by: Gilad Broner Signed-off-by: Subhash Jadavani --- drivers/scsi/ufs/ufshcd.c | 15 ++++++--------- 1 file changed, 6 insertions(+), 9 deletions(-) diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c index b826078..4b6cc07 100644 --- a/drivers/scsi/ufs/ufshcd.c +++ b/drivers/scsi/ufs/ufshcd.c @@ -6272,16 +6272,13 @@ int ufshcd_system_suspend(struct ufs_hba *hba) if (!hba || !hba->is_powered) return 0; - if (pm_runtime_suspended(hba->dev)) { - if (hba->rpm_lvl == hba->spm_lvl) - /* - * There is possibility that device may still be in - * active state during the runtime suspend. - */ - if ((ufs_get_pm_lvl_to_dev_pwr_mode(hba->spm_lvl) == - hba->curr_dev_pwr_mode) && !hba->auto_bkops_enabled) - goto out; + if ((ufs_get_pm_lvl_to_dev_pwr_mode(hba->spm_lvl) == + hba->curr_dev_pwr_mode) && + (ufs_get_pm_lvl_to_link_pwr_state(hba->spm_lvl) == + hba->uic_link_state)) + goto out; + if (pm_runtime_suspended(hba->dev)) { /* * UFS device and/or UFS link low power states during runtime * suspend seems to be different than what is expected during -- The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project