From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752730AbaJPOFJ (ORCPT ); Thu, 16 Oct 2014 10:05:09 -0400 Received: from mailout4.w1.samsung.com ([210.118.77.14]:43160 "EHLO mailout4.w1.samsung.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751587AbaJPOFG (ORCPT ); Thu, 16 Oct 2014 10:05:06 -0400 X-AuditID: cbfec7f4-b7f156d0000063c7-1d-543fd0903721 Message-id: <1413468302.5605.9.camel@AMDC1943> Subject: PM/runtime issue: Device cannot runtime resume because power domain is off during system resume From: Krzysztof Kozlowski To: "Rafael J. Wysocki" , Pavel Machek , Len Brown , linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org Date: Thu, 16 Oct 2014 16:05:02 +0200 Content-type: text/plain; charset=UTF-8 X-Mailer: Evolution 3.10.4-0ubuntu2 MIME-version: 1.0 Content-transfer-encoding: 7bit X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFupmluLIzCtJLcpLzFFi42I5/e/4Zd0JF+xDDC4v47KYNWUvk8XlXXPY LD73HmG0uHvqKJvFmdOXWB1YPRbvecnkseVqO4vHitXf2T0+b5ILYInisklJzcksSy3St0vg yljzeQ57wSbuigd3GlkaGL9xdDFyckgImEh8efWVDcIWk7hwbz2QzcUhJLCUUWLDmnOMEM5n Rokpc64wg1TxCuhJtK56zg5iCwtkSdza9IAFxGYTMJbYvHwJWLcISPecMx8YQRIsAqoSl/bs B1vBLKAuMWneIqBBHEDrlCUa+90gZgpK/Jh8jwWiRF5i85q3zBMYeWch6ZiFpGwWkrIFjMyr GEVTS5MLipPScw31ihNzi0vz0vWS83M3MUIC8MsOxsXHrA4xCnAwKvHwagTbhwixJpYVV+Ye YpTgYFYS4T12CijEm5JYWZValB9fVJqTWnyIkYmDU6qBkcXl9X2V6+0JHGmP57FWPNY67yTt 3T2d70v3/oUs7vGntd7/lf0iunadpaz53yPOiwN3d+5YYToxWO2fRPXRfqUZ3vdDPrtld6tI GJX/ODzpnqD0niIngXdX9f7mTRef7fjuneGUi62rJA5ovT72Madh40PPVzNtnxybs9jw5hsX v/m1qrG895RYijMSDbWYi4oTASmaFLceAgAA Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, I encounter issues with DRM/panel driver for Exynos after resuming from suspend to RAM. This is reproduced on 3.16 but I think it is applicable also to mainline. The scenario: 0. DRM DSI is in LCD power domain. Power domain is OFF before suspending. 1. System suspends. 2. System resumes. 3. DRM driver:resume(). 4. pm_runtime_get() for DRM DSI driver. 5. This should enable LCD power domain. 6. but __pm_genpd_poweron() exits early because: genpd->prepared_count = 3 genpd->suspend_power_off = 1 in domain.c:183 7. The domain is not powered on but it is marked as active. 8. The DRM driver thinks everything is OK and proceeds with resume... but it fails because whole power domain is OFF. The question: Shouldn't the power domain be powered up EARLY? Something like this: diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c index 40bc2f4072cc..4fdfe404a04c 100644 --- a/drivers/base/power/domain.c +++ b/drivers/base/power/domain.c @@ -179,8 +179,7 @@ static int __pm_genpd_poweron(struct } finish_wait(&genpd->status_wait_queue, &wait); - if (genpd->status == GPD_STATE_ACTIVE - || (genpd->prepared_count > 0 && genpd->suspend_power_off)) + if (genpd->status == GPD_STATE_ACTIVE) return 0; if (genpd->status != GPD_STATE_POWER_OFF) { If not... how to solve the scenario above? Best regards, Krzyszto