From patchwork Fri Dec 8 12:30:47 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Vivek Gautam X-Patchwork-Id: 10102445 X-Patchwork-Delegate: agross@codeaurora.org Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 02DDF602A0 for ; Fri, 8 Dec 2017 12:31:13 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id C422528B9B for ; Fri, 8 Dec 2017 12:31:12 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id B89B828C16; Fri, 8 Dec 2017 12:31:12 +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=-6.8 required=2.0 tests=BAYES_00,DKIM_SIGNED, RCVD_IN_DNSWL_HI,T_DKIM_INVALID autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 3E0FE28B9B for ; Fri, 8 Dec 2017 12:31:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752588AbdLHMbL (ORCPT ); Fri, 8 Dec 2017 07:31:11 -0500 Received: from smtp.codeaurora.org ([198.145.29.96]:43572 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752546AbdLHMbK (ORCPT ); Fri, 8 Dec 2017 07:31:10 -0500 Received: by smtp.codeaurora.org (Postfix, from userid 1000) id 8BB5960819; Fri, 8 Dec 2017 12:31:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=codeaurora.org; s=default; t=1512736269; bh=R5oTCGwiJyuwWDjnh7FVBnvqcX0bex2E3LVUSM8YAx0=; h=From:To:Cc:Subject:Date:From; b=eI4al47KEReAWzNSAjPK5CbK1s/7MYqBLNCkmsccTgIaYAw8WwBx6UtfrqfP3YyTH /FEgr6VUv+Iz0mIQLwhqbRbRp5Wypo01EBqpv5FsIyyO2f6DDO5CdKARHHMX9boBbD nLGJd0CtV/Uo8zh8/pDq7Wql2el5cCYQBlkTLkwI= Received: from blr-ubuntu-41.ap.qualcomm.com (blr-bdr-fw-01_globalnat_allzones-outside.qualcomm.com [103.229.18.19]) (using TLSv1.1 with cipher ECDHE-RSA-AES128-SHA (128/128 bits)) (No client certificate requested) (Authenticated sender: vivek.gautam@smtp.codeaurora.org) by smtp.codeaurora.org (Postfix) with ESMTPSA id C025C60218; Fri, 8 Dec 2017 12:31:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=codeaurora.org; s=default; t=1512736268; bh=R5oTCGwiJyuwWDjnh7FVBnvqcX0bex2E3LVUSM8YAx0=; h=From:To:Cc:Subject:Date:From; b=WvupPZWGSFWahnxunLCjKGqTRQHMFqpBNyUSsEd2wur60KTyCblZ6u4ca9F8JbNrh ZIHsZzc156YcdRBWeQHyzVc/rk7DbfFRQasuTlPRNX91ekxLvDoSPm8D7/GXa1Yb+v Y/m2f/Y1j3iK8scyIHcBFD1YygyP6Q6BC/+TxVro= DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org C025C60218 Authentication-Results: pdx-caf-mail.web.codeaurora.org; dmarc=none (p=none dis=none) header.from=codeaurora.org Authentication-Results: pdx-caf-mail.web.codeaurora.org; spf=none smtp.mailfrom=vivek.gautam@codeaurora.org From: Vivek Gautam To: rjw@rjwysocki.net, len.brown@intel.com, pavel@ucw.cz, gregkh@linuxfoundation.org Cc: linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org, sboyd@codeaurora.org, robdclark@gmail.com, robin.murphy@arm.com, will.deacon@arm.com, linux-arm-msm@vger.kernel.org, Vivek Gautam Subject: [PATCH 1/1] base: power: runtime: Export pm_runtime_get/put_suppliers Date: Fri, 8 Dec 2017 18:00:47 +0530 Message-Id: <1512736247-16538-1-git-send-email-vivek.gautam@codeaurora.org> X-Mailer: git-send-email 1.9.1 Sender: linux-arm-msm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP The device link allows the pm framework to tie the supplier and consumer. So, whenever the consumer is powered-on, the supplier is powered-on first. There are however cases in which the consumer wants to power-on the supplier, but not itself. E.g., A Graphics or multimedia driver wants to power-on the SMMU to unmap a buffer and finish the TLB operations without powering on itself. Some of these unmap requests are coming from the user space when the controller itself is not powered-up, and it can be huge penalty in terms of power and latency to power-up the graphics/mm controllers. There can be an argument that the supplier should handle this case on its own and there should not be a need for the consumer to power-on the supplier. But as discussed on the thread [1] about ARM-SMMU runtime pm, we don't want to introduce runtime pm calls in atomic paths, such as in arm_smmu_unmap. [1] https://patchwork.kernel.org/patch/9827825/ Signed-off-by: Vivek Gautam --- drivers/base/power/runtime.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/base/power/runtime.c b/drivers/base/power/runtime.c index 027d159ac381..af169304ca13 100644 --- a/drivers/base/power/runtime.c +++ b/drivers/base/power/runtime.c @@ -1578,6 +1578,7 @@ void pm_runtime_get_suppliers(struct device *dev) device_links_read_unlock(idx); } +EXPORT_SYMBOL_GPL(pm_runtime_get_suppliers); /** * pm_runtime_put_suppliers - Drop references to supplier devices. @@ -1596,6 +1597,7 @@ void pm_runtime_put_suppliers(struct device *dev) device_links_read_unlock(idx); } +EXPORT_SYMBOL_GPL(pm_runtime_put_suppliers); void pm_runtime_new_link(struct device *dev) {