Commit 4f3ceca2 authored by Pierre-Yves MORDRET's avatar Pierre-Yves MORDRET Committed by Vinod Koul
Browse files

dmaengine: stm32-dmamux: 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 48bc73ba

drivers/dma/stm32-dmamux.c

+47 −11
Original line number Diff line number Diff line
@@ -28,6 +28,7 @@ 
#include <linux/module.h>

#include <linux/of_device.h>

#include <linux/of_dma.h>

#include <linux/pm_runtime.h>

#include <linux/reset.h>

#include <linux/slab.h>

#include <linux/spinlock.h>
@@ -79,8 +80,7 @@ static void stm32_dmamux_free(struct device *dev, void *route_data) 
	stm32_dmamux_write(dmamux->iomem, STM32_DMAMUX_CCR(mux->chan_id), 0);

	clear_bit(mux->chan_id, dmamux->dma_inuse);



	if (!IS_ERR(dmamux->clk))

		clk_disable(dmamux->clk);

	pm_runtime_put_sync(dev);



	spin_unlock_irqrestore(&dmamux->lock, flags);
@@ -146,14 +146,11 @@ static void *stm32_dmamux_route_allocate(struct of_phandle_args *dma_spec, 


	/* Set dma request */

	spin_lock_irqsave(&dmamux->lock, flags);

	if (!IS_ERR(dmamux->clk)) {

		ret = clk_enable(dmamux->clk);

	ret = pm_runtime_get_sync(&pdev->dev);

	if (ret < 0) {

		spin_unlock_irqrestore(&dmamux->lock, flags);

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

		goto error;

	}

	}

	spin_unlock_irqrestore(&dmamux->lock, flags);



	mux->request = dma_spec->args[0];
@@ -254,6 +251,7 @@ static int stm32_dmamux_probe(struct platform_device *pdev) 
		dev_warn(&pdev->dev, "DMAMUX defaulting on %u requests\n",

			 stm32_dmamux->dmamux_requests);

	}

	pm_runtime_get_noresume(&pdev->dev);



	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);

	iomem = devm_ioremap_resource(&pdev->dev, res);
@@ -282,6 +280,8 @@ static int stm32_dmamux_probe(struct platform_device *pdev) 
	stm32_dmamux->dmarouter.route_free = stm32_dmamux_free;



	platform_set_drvdata(pdev, stm32_dmamux);

	pm_runtime_set_active(&pdev->dev);

	pm_runtime_enable(&pdev->dev);



	if (!IS_ERR(stm32_dmamux->clk)) {

		ret = clk_prepare_enable(stm32_dmamux->clk);
@@ -291,17 +291,52 @@ static int stm32_dmamux_probe(struct platform_device *pdev) 
		}

	}



	pm_runtime_get_noresume(&pdev->dev);



	/* Reset the dmamux */

	for (i = 0; i < stm32_dmamux->dma_requests; i++)

		stm32_dmamux_write(stm32_dmamux->iomem, STM32_DMAMUX_CCR(i), 0);



	if (!IS_ERR(stm32_dmamux->clk))

		clk_disable(stm32_dmamux->clk);

	pm_runtime_put(&pdev->dev);



	return of_dma_router_register(node, stm32_dmamux_route_allocate,

				     &stm32_dmamux->dmarouter);

}



#ifdef CONFIG_PM

static int stm32_dmamux_runtime_suspend(struct device *dev)

{

	struct platform_device *pdev =

		container_of(dev, struct platform_device, dev);

	struct stm32_dmamux_data *stm32_dmamux = platform_get_drvdata(pdev);



	clk_disable_unprepare(stm32_dmamux->clk);



	return 0;

}



static int stm32_dmamux_runtime_resume(struct device *dev)

{

	struct platform_device *pdev =

		container_of(dev, struct platform_device, dev);

	struct stm32_dmamux_data *stm32_dmamux = platform_get_drvdata(pdev);

	int ret;



	ret = clk_prepare_enable(stm32_dmamux->clk);

	if (ret) {

		dev_err(&pdev->dev, "failed to prepare_enable clock\n");

		return ret;

	}



	return 0;

}

#endif



static const struct dev_pm_ops stm32_dmamux_pm_ops = {

	SET_RUNTIME_PM_OPS(stm32_dmamux_runtime_suspend,

			   stm32_dmamux_runtime_resume, NULL)

};



static const struct of_device_id stm32_dmamux_match[] = {

	{ .compatible = "st,stm32h7-dmamux" },

	{},
@@ -312,6 +347,7 @@ static struct platform_driver stm32_dmamux_driver = { 
	.driver = {

		.name = "stm32-dmamux",

		.of_match_table = stm32_dmamux_match,

		.pm = &stm32_dmamux_pm_ops,

	},

};