Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758238Ab2JXLPW (ORCPT ); Wed, 24 Oct 2012 07:15:22 -0400 Received: from casper.infradead.org ([85.118.1.10]:59080 "EHLO casper.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751599Ab2JXLPV (ORCPT ); Wed, 24 Oct 2012 07:15:21 -0400 Subject: Re: [PATCH] DMA: PL330: Add runtime pm support From: Vinod Koul To: Inderpal Singh Cc: vinod.koul@intel.com, linux-samsung-soc@vger.kernel.org, linux-kernel@vger.kernel.org, jassisinghbrar@gmail.com, boojin.kim@samsung.com, kgene.kim@samsung.com, patches@linaro.org In-Reply-To: <1350447151-16737-1-git-send-email-inderpal.singh@linaro.org> References: <1350447151-16737-1-git-send-email-inderpal.singh@linaro.org> Content-Type: text/plain; charset="UTF-8" Date: Wed, 24 Oct 2012 10:24:01 +0530 Message-ID: <1351054441.5263.52.camel@vkoul-udesk3> Mime-Version: 1.0 X-Mailer: Evolution 2.28.3 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2977 Lines: 92 On Wed, 2012-10-17 at 09:42 +0530, Inderpal Singh wrote: > At the pl330's probe point the device is already in runtime resume state. > Hence to manage the device with runtime, the probe should do pm_runtime_put > and remove should do pm_runtime_get to balance with probe. > > And in between, the device is being get/put at alloc_chan_resources and > free_chan_resources. > > Signed-off-by: Inderpal Singh > --- > This patch is based on slave-dma's next branch and on top > of the clean up patches at [1]. > > [1] https://lkml.org/lkml/2012/10/5/169 > > drivers/dma/pl330.c | 10 ++++++++++ > 1 file changed, 10 insertions(+) > > diff --git a/drivers/dma/pl330.c b/drivers/dma/pl330.c > index 2ee1538..5ae19ea 100644 > --- a/drivers/dma/pl330.c > +++ b/drivers/dma/pl330.c > @@ -25,6 +25,7 @@ > #include > #include > #include > +#include > > #include "dmaengine.h" > #define PL330_MAX_CHAN 8 > @@ -2384,6 +2385,8 @@ static int pl330_alloc_chan_resources(struct dma_chan *chan) > struct dma_pl330_dmac *pdmac = pch->dmac; > unsigned long flags; > > + pm_runtime_get_sync(pdmac->ddma.dev); it would be really good if we move this to tx_submit. That way you resume the dmaengine when actual transactions happen, not when someone requests a channel. Yes thats a little more work, though initially we can have this way. > + > spin_lock_irqsave(&pch->lock, flags); > > dma_cookie_init(chan); > @@ -2392,6 +2395,7 @@ static int pl330_alloc_chan_resources(struct dma_chan *chan) > pch->pl330_chid = pl330_request_channel(&pdmac->pif); > if (!pch->pl330_chid) { > spin_unlock_irqrestore(&pch->lock, flags); > + pm_runtime_put(pdmac->ddma.dev); > return -ENOMEM; > } > > @@ -2470,6 +2474,8 @@ static void pl330_free_chan_resources(struct dma_chan *chan) > list_splice_tail_init(&pch->work_list, &pch->dmac->desc_pool); > > spin_unlock_irqrestore(&pch->lock, flags); > + > + pm_runtime_put(pch->dmac->ddma.dev); > } > > static enum dma_status > @@ -2974,6 +2980,8 @@ pl330_probe(struct amba_device *adev, const struct amba_id *id) > pi->pcfg.data_bus_width / 8, pi->pcfg.num_chan, > pi->pcfg.num_peri, pi->pcfg.num_events); > > + pm_runtime_put(pd->dev); pm_runtime_put_noidle is better. Yous should also do pm_runtime_allow here and pm_runtime_forbid in your remove. > + > return 0; > > probe_err5: > @@ -3017,6 +3025,8 @@ static int __devexit pl330_remove(struct amba_device *adev) > return -EBUSY; > } > > + pm_runtime_get(pdmac->ddma.dev); > + > dma_async_device_unregister(&pdmac->ddma); > > amba_set_drvdata(adev, NULL); -- Vinod Koul Intel Corp. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/