From patchwork Fri Jan 19 11:43:38 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Vivek Gautam X-Patchwork-Id: 10175081 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 8B0A760386 for ; Fri, 19 Jan 2018 11:44:51 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 7ACCB285CA for ; Fri, 19 Jan 2018 11:44:51 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 6EF3828672; Fri, 19 Jan 2018 11:44:51 +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 D0BAF285CA for ; Fri, 19 Jan 2018 11:44:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754562AbeASLoM (ORCPT ); Fri, 19 Jan 2018 06:44:12 -0500 Received: from smtp.codeaurora.org ([198.145.29.96]:46036 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755283AbeASLoE (ORCPT ); Fri, 19 Jan 2018 06:44:04 -0500 Received: by smtp.codeaurora.org (Postfix, from userid 1000) id 155F860A54; Fri, 19 Jan 2018 11:44:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=codeaurora.org; s=default; t=1516362244; bh=1yVWhKRVZq1GDeX2n2rnUcLuX6x2bTiK5dbE+b1ItqY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=VcyXWhRBYCrvkxO9dqLADSaGgP6fFKnANy9ic91NOO12TkII7EbH0C8zZXFyjk5oy sm4C0oTuD82QXp7oUg1ouNg0o++XjUFNADnybWm1KIMp3lPy9nZkwuQ9qu6PlTbju9 iTn+AaWXDYIyocuSpR4Aagn/+Z1DOjAVvgW+3bEs= 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 3AC9B609D1; Fri, 19 Jan 2018 11:43:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=codeaurora.org; s=default; t=1516362243; bh=1yVWhKRVZq1GDeX2n2rnUcLuX6x2bTiK5dbE+b1ItqY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=gNWYVjbDrvO0L1tfhhpzUNdTxe4Hkw7L+KJBweaj9shxRMSrU5TIsRWOTsy/Y8aiO b/+/+OWYq57FA22AEiOZlrZ/h3u1ubuZ3WBUxw5CIDjrtW0noJ9nBickTuC7vAbZ5z 8PXXPxmb40thOCM/b68ty0TuzmJccV+/gLqn+VlY= DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org 3AC9B609D1 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: alex.williamson@redhat.com, robh+dt@kernel.org, mark.rutland@arm.com, rjw@rjwysocki.net, robin.murphy@arm.com, will.deacon@arm.com, iommu@lists.linux-foundation.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org, dri-devel@lists.freedesktop.org, freedreno@lists.freedesktop.org, sboyd@codeaurora.org Cc: gregkh@linuxfoundation.org, sricharan@codeaurora.org, m.szyprowski@samsung.com, architt@codeaurora.org, linux-arm-msm@vger.kernel.org, vivek.gautam@codeaurora.org Subject: [PATCH v6 1/6] base: power: runtime: Export pm_runtime_get/put_suppliers Date: Fri, 19 Jan 2018 17:13:38 +0530 Message-Id: <1516362223-22946-2-git-send-email-vivek.gautam@codeaurora.org> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1516362223-22946-1-git-send-email-vivek.gautam@codeaurora.org> References: <1516362223-22946-1-git-send-email-vivek.gautam@codeaurora.org> Sender: linux-pm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pm@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 path in arm_smmu_unmap. [1] https://patchwork.kernel.org/patch/9827825/ Signed-off-by: Vivek Gautam Acked-by: Rafael J. Wysocki --- 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 6e89b51ea3d9..06a2a88fe866 100644 --- a/drivers/base/power/runtime.c +++ b/drivers/base/power/runtime.c @@ -1579,6 +1579,7 @@ 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. @@ -1597,6 +1598,7 @@ 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) {