Commit 89e987e3 authored by Pierre-Yves MORDRET's avatar Pierre-Yves MORDRET Committed by Vinod Koul
Browse files

dmaengine: stm32-mdma: Add PM Runtime support 



Use pm_runtime engine for clock management purpose

Signed-off-by: default avatarPierre-Yves MORDRET <pierre-yves.mordret@st.com>
Signed-off-by: default avatarVinod Koul <vkoul@kernel.org>
parent 4f3ceca2

drivers/dma/stm32-mdma.c

+46 −6
Original line number Diff line number Diff line
@@ -37,6 +37,7 @@ 
#include <linux/of_device.h>

#include <linux/of_dma.h>

#include <linux/platform_device.h>

#include <linux/pm_runtime.h>

#include <linux/reset.h>

#include <linux/slab.h>
@@ -1456,15 +1457,13 @@ static int stm32_mdma_alloc_chan_resources(struct dma_chan *c) 
		return -ENOMEM;

	}



	ret = clk_prepare_enable(dmadev->clk);

	if (ret < 0) {

		dev_err(chan2dev(chan), "clk_prepare_enable failed: %d\n", ret);

	ret = pm_runtime_get_sync(dmadev->ddev.dev);

	if (ret < 0)

		return ret;

	}



	ret = stm32_mdma_disable_chan(chan);

	if (ret < 0)

		clk_disable_unprepare(dmadev->clk);

		pm_runtime_put(dmadev->ddev.dev);



	return ret;

}
@@ -1484,7 +1483,7 @@ static void stm32_mdma_free_chan_resources(struct dma_chan *c) 
		spin_unlock_irqrestore(&chan->vchan.lock, flags);

	}



	clk_disable_unprepare(dmadev->clk);

	pm_runtime_put(dmadev->ddev.dev);

	vchan_free_chan_resources(to_virt_chan(c));

	dmam_pool_destroy(chan->desc_pool);

	chan->desc_pool = NULL;
@@ -1599,6 +1598,12 @@ static int stm32_mdma_probe(struct platform_device *pdev) 
		return ret;

	}



	ret = clk_prepare_enable(dmadev->clk);

	if (ret < 0) {

		dev_err(&pdev->dev, "clk_prep_enable error: %d\n", ret);

		return ret;

	}



	dmadev->rst = devm_reset_control_get(&pdev->dev, NULL);

	if (!IS_ERR(dmadev->rst)) {

		reset_control_assert(dmadev->rst);
@@ -1670,6 +1675,10 @@ static int stm32_mdma_probe(struct platform_device *pdev) 
	}



	platform_set_drvdata(pdev, dmadev);

	pm_runtime_set_active(&pdev->dev);

	pm_runtime_enable(&pdev->dev);

	pm_runtime_get_noresume(&pdev->dev);

	pm_runtime_put(&pdev->dev);



	dev_info(&pdev->dev, "STM32 MDMA driver registered\n");
@@ -1679,11 +1688,42 @@ static int stm32_mdma_probe(struct platform_device *pdev) 
	return ret;

}



#ifdef CONFIG_PM

static int stm32_mdma_runtime_suspend(struct device *dev)

{

	struct stm32_mdma_device *dmadev = dev_get_drvdata(dev);



	clk_disable_unprepare(dmadev->clk);



	return 0;

}



static int stm32_mdma_runtime_resume(struct device *dev)

{

	struct stm32_mdma_device *dmadev = dev_get_drvdata(dev);

	int ret;



	ret = clk_prepare_enable(dmadev->clk);

	if (ret) {

		dev_err(dev, "failed to prepare_enable clock\n");

		return ret;

	}



	return 0;

}

#endif



static const struct dev_pm_ops stm32_mdma_pm_ops = {

	SET_RUNTIME_PM_OPS(stm32_mdma_runtime_suspend,

			   stm32_mdma_runtime_resume, NULL)

};



static struct platform_driver stm32_mdma_driver = {

	.probe = stm32_mdma_probe,

	.driver = {

		.name = "stm32-mdma",

		.of_match_table = stm32_mdma_of_match,

		.pm = &stm32_mdma_pm_ops,

	},

};