From mboxrd@z Thu Jan 1 00:00:00 1970 From: Vivek Gautam Subject: [PATCH v5 1/6] base: power: runtime: Export pm_runtime_get/put_suppliers Date: Tue, 9 Jan 2018 15:31:44 +0530 Message-ID: <1515492109-753-2-git-send-email-vivek.gautam@codeaurora.org> References: <1515492109-753-1-git-send-email-vivek.gautam@codeaurora.org> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1515492109-753-1-git-send-email-vivek.gautam-sgV2jX0FEOL9JmXXK+q4OQ@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: iommu-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org Errors-To: iommu-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org To: joro-zLv9SwRftAIdnm+yROfE0A@public.gmane.org, robh+dt-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org, mark.rutland-5wv7dgnIgG8@public.gmane.org, rjw-LthD3rsA81gm4RdzfppkhA@public.gmane.org, gregkh-hQyY1W1yCW8ekmWlsbkhG0B+6BGkLq7r@public.gmane.org, robdclark-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org, will.deacon-5wv7dgnIgG8@public.gmane.org, robin.murphy-5wv7dgnIgG8@public.gmane.org, sboyd-sgV2jX0FEOL9JmXXK+q4OQ@public.gmane.org, iommu-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org, devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-pm-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, dri-devel-PD4FTy7X32lNgt0PjOBp9y5qC8QIuHrW@public.gmane.org, freedreno-PD4FTy7X32lNgt0PjOBp9y5qC8QIuHrW@public.gmane.org Cc: len.brown-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org, airlied-cv59FeDIM0c@public.gmane.org, linux-arm-msm-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, pavel-+ZI9xUNit7I@public.gmane.org List-Id: iommu@lists.linux-foundation.org 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 --- * This is v2 of the patch [1]. Adding it to this patch series. [1] https://patchwork.kernel.org/patch/10102447/ 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) { -- QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by The Linux Foundation