dmaengine: stm32-dmamux: add suspend/resume power management support (f65c2e14) · Commits · 戴 / test

drivers/dma/stm32-dmamux.c

+50 −0

Original line number	Diff line number	Diff line
		@@ -41,6 +41,9 @@ struct stm32_dmamux_data {
		u32 dmamux_requests; /* Number of DMA requests routed toward DMAs */
		spinlock_t lock; /* Protects register access */
		unsigned long dma_inuse; / Used DMA channel */
		u32 ccr[STM32_DMAMUX_MAX_DMA_REQUESTS]; /* Used to backup CCR register
		* in suspend
		*/
		u32 dma_reqs[]; /* Number of DMA Request per DMA masters.
		* [0] holds number of DMA Masters.
		* To be kept at very end end of this structure
		@@ -318,7 +321,54 @@ static int stm32_dmamux_runtime_resume(struct device *dev)
		}
		#endif

		#ifdef CONFIG_PM_SLEEP
		static int stm32_dmamux_suspend(struct device *dev)
		{
		struct platform_device *pdev = to_platform_device(dev);
		struct stm32_dmamux_data *stm32_dmamux = platform_get_drvdata(pdev);
		int i, ret;

		ret = pm_runtime_get_sync(dev);
		if (ret < 0)
		return ret;

		for (i = 0; i < stm32_dmamux->dma_requests; i++)
		stm32_dmamux->ccr[i] = stm32_dmamux_read(stm32_dmamux->iomem,
		STM32_DMAMUX_CCR(i));

		pm_runtime_put_sync(dev);

		pm_runtime_force_suspend(dev);

		return 0;
		}

		static int stm32_dmamux_resume(struct device *dev)
		{
		struct platform_device *pdev = to_platform_device(dev);
		struct stm32_dmamux_data *stm32_dmamux = platform_get_drvdata(pdev);
		int i, ret;

		ret = pm_runtime_force_resume(dev);
		if (ret < 0)
		return ret;

		ret = pm_runtime_get_sync(dev);
		if (ret < 0)
		return ret;

		for (i = 0; i < stm32_dmamux->dma_requests; i++)
		stm32_dmamux_write(stm32_dmamux->iomem, STM32_DMAMUX_CCR(i),
		stm32_dmamux->ccr[i]);

		pm_runtime_put_sync(dev);

		return 0;
		}
		#endif

		static const struct dev_pm_ops stm32_dmamux_pm_ops = {
		SET_SYSTEM_SLEEP_PM_OPS(stm32_dmamux_suspend, stm32_dmamux_resume)
		SET_RUNTIME_PM_OPS(stm32_dmamux_runtime_suspend,
		stm32_dmamux_runtime_resume, NULL)
		};

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