Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752145AbbKINYR (ORCPT ); Mon, 9 Nov 2015 08:24:17 -0500 Received: from hqemgate16.nvidia.com ([216.228.121.65]:19608 "EHLO hqemgate16.nvidia.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752009AbbKINYL (ORCPT ); Mon, 9 Nov 2015 08:24:11 -0500 X-PGP-Universal: processed; by hqnvupgp08.nvidia.com on Mon, 09 Nov 2015 05:21:59 -0800 From: Jon Hunter To: Laxman Dewangan , Vinod Koul , Stephen Warren , Thierry Reding , Alexandre Courbot CC: , , , Jon Hunter Subject: [PATCH V2 1/6] dmaengine: tegra-apb: Correct runtime-pm usage Date: Mon, 9 Nov 2015 13:23:44 +0000 Message-ID: <1447075429-27311-2-git-send-email-jonathanh@nvidia.com> X-Mailer: git-send-email 2.1.4 In-Reply-To: <1447075429-27311-1-git-send-email-jonathanh@nvidia.com> References: <1447075429-27311-1-git-send-email-jonathanh@nvidia.com> X-NVConfidentiality: public MIME-Version: 1.0 Content-Type: text/plain Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4648 Lines: 156 The tegra-apb DMA driver enables runtime-pm but never calls pm_runtime_get/put and hence the runtime-pm callbacks are never invoked. The driver manages the clocks by directly calling clk_prepare_enable() and clk_unprepare_disable(). Fix this by replacing the clk_prepare_enable() and clk_disable_unprepare() with pm_runtime_get_sync() and pm_runtime_put(), respectively. Note that the consequence of this is that if runtime-pm is disabled, then the clocks will remain on the entire time the driver is loaded. However, if runtime-pm is disabled, then power is not most likely not a concern. Signed-off-by: Jon Hunter --- V2 changes: - Fixed return value for allocating channel - Fixed test for return value from pm_runtime_get_sync() drivers/dma/tegra20-apb-dma.c | 49 ++++++++++++++++++------------------------- 1 file changed, 20 insertions(+), 29 deletions(-) diff --git a/drivers/dma/tegra20-apb-dma.c b/drivers/dma/tegra20-apb-dma.c index c8f79dcaaee8..6007111fac1d 100644 --- a/drivers/dma/tegra20-apb-dma.c +++ b/drivers/dma/tegra20-apb-dma.c @@ -1186,10 +1186,12 @@ static int tegra_dma_alloc_chan_resources(struct dma_chan *dc) dma_cookie_init(&tdc->dma_chan); tdc->config_init = false; - ret = clk_prepare_enable(tdma->dma_clk); + + ret = pm_runtime_get_sync(tdma->dev); if (ret < 0) - dev_err(tdc2dev(tdc), "clk_prepare_enable failed: %d\n", ret); - return ret; + return ret; + + return 0; } static void tegra_dma_free_chan_resources(struct dma_chan *dc) @@ -1232,7 +1234,7 @@ static void tegra_dma_free_chan_resources(struct dma_chan *dc) list_del(&sg_req->node); kfree(sg_req); } - clk_disable_unprepare(tdma->dma_clk); + pm_runtime_put(tdma->dev); tdc->slave_id = 0; } @@ -1356,20 +1358,14 @@ static int tegra_dma_probe(struct platform_device *pdev) spin_lock_init(&tdma->global_lock); pm_runtime_enable(&pdev->dev); - if (!pm_runtime_enabled(&pdev->dev)) { + if (!pm_runtime_enabled(&pdev->dev)) ret = tegra_dma_runtime_resume(&pdev->dev); - if (ret) { - dev_err(&pdev->dev, "dma_runtime_resume failed %d\n", - ret); - goto err_pm_disable; - } - } + else + ret = pm_runtime_get_sync(&pdev->dev); - /* Enable clock before accessing registers */ - ret = clk_prepare_enable(tdma->dma_clk); if (ret < 0) { - dev_err(&pdev->dev, "clk_prepare_enable failed: %d\n", ret); - goto err_pm_disable; + pm_runtime_disable(&pdev->dev); + return ret; } /* Reset DMA controller */ @@ -1382,7 +1378,7 @@ static int tegra_dma_probe(struct platform_device *pdev) tdma_write(tdma, TEGRA_APBDMA_CONTROL, 0); tdma_write(tdma, TEGRA_APBDMA_IRQ_MASK_SET, 0xFFFFFFFFul); - clk_disable_unprepare(tdma->dma_clk); + pm_runtime_put(&pdev->dev); INIT_LIST_HEAD(&tdma->dma_dev.channels); for (i = 0; i < cdata->nr_channels; i++) { @@ -1485,7 +1481,6 @@ err_irq: tasklet_kill(&tdc->tasklet); } -err_pm_disable: pm_runtime_disable(&pdev->dev); if (!pm_runtime_status_suspended(&pdev->dev)) tegra_dma_runtime_suspend(&pdev->dev); @@ -1539,11 +1534,10 @@ static int tegra_dma_runtime_resume(struct device *dev) static int tegra_dma_pm_suspend(struct device *dev) { struct tegra_dma *tdma = dev_get_drvdata(dev); - int i; - int ret; + int i, ret; /* Enable clock before accessing register */ - ret = tegra_dma_runtime_resume(dev); + ret = pm_runtime_get_sync(dev); if (ret < 0) return ret; @@ -1560,18 +1554,17 @@ static int tegra_dma_pm_suspend(struct device *dev) } /* Disable clock */ - tegra_dma_runtime_suspend(dev); + pm_runtime_put(dev); return 0; } static int tegra_dma_pm_resume(struct device *dev) { struct tegra_dma *tdma = dev_get_drvdata(dev); - int i; - int ret; + int i, ret; /* Enable clock before accessing register */ - ret = tegra_dma_runtime_resume(dev); + ret = pm_runtime_get_sync(dev); if (ret < 0) return ret; @@ -1592,16 +1585,14 @@ static int tegra_dma_pm_resume(struct device *dev) } /* Disable clock */ - tegra_dma_runtime_suspend(dev); + pm_runtime_put(dev); return 0; } #endif static const struct dev_pm_ops tegra_dma_dev_pm_ops = { -#ifdef CONFIG_PM - .runtime_suspend = tegra_dma_runtime_suspend, - .runtime_resume = tegra_dma_runtime_resume, -#endif + SET_RUNTIME_PM_OPS(tegra_dma_runtime_suspend, tegra_dma_runtime_resume, + NULL) SET_SYSTEM_SLEEP_PM_OPS(tegra_dma_pm_suspend, tegra_dma_pm_resume) }; -- 2.1.4 -- 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/