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[PATCH v2 5/7] dmaengine: dw: platform: power on device on shutdown

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We have to call dw_dma_disable() to stop any ongoing transfer. On some
platforms we can't do that since DMA device is powered off. Moreover we have no
possibility at that point to check if the platform is affected or not. That's
why we call pm_runtime_get_sync() / pm_runtime_put() unconditionally. On the
other hand we can't use pm_runtime_suspended() because runtime PM framework is
not fully used by the driver.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
 drivers/dma/dw/platform.c | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/drivers/dma/dw/platform.c b/drivers/dma/dw/platform.c
index 68a4815..d0734e9 100644
--- a/drivers/dma/dw/platform.c
+++ b/drivers/dma/dw/platform.c
@@ -239,7 +239,19 @@ static void dw_shutdown(struct platform_device *pdev)
 {
 	struct dw_dma_chip *chip = platform_get_drvdata(pdev);
 
+	/*
+	 * We have to call dw_dma_disable() to stop any ongoing transfer. On
+	 * some platforms we can't do that since DMA device is powered off.
+	 * Moreover we have no possibility to check if the platform is affected
+	 * or not. That's why we call pm_runtime_get_sync() / pm_runtime_put()
+	 * unconditionally. On the other hand we can't use
+	 * pm_runtime_suspended() because runtime PM framework is not fully
+	 * used by the driver.
+	 */
+	pm_runtime_get_sync(chip->dev);
 	dw_dma_disable(chip);
+	pm_runtime_put_sync_suspend(chip->dev);
+
 	clk_disable_unprepare(chip->clk);
 }
 
-- 
2.6.2

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[PATCH v2 5/7] dmaengine: dw: platform: power on device on shutdown Andy Shevchenko <andriy.shevchenko@linux.intel.com> - 2015-11-26 16:30 +0100
  Re: [PATCH v2 5/7] dmaengine: dw: platform: power on device on  shutdown Vinod Koul <vinod.koul@intel.com> - 2015-11-26 18:00 +0100
    Re: [PATCH v2 5/7] dmaengine: dw: platform: power on device on  shutdown Andy Shevchenko <andriy.shevchenko@linux.intel.com> - 2015-11-26 18:30 +0100
      Re: [PATCH v2 5/7] dmaengine: dw: platform: power on device on  shutdown Vinod Koul <vinod.koul@intel.com> - 2015-11-26 18:40 +0100
        Re: [PATCH v2 5/7] dmaengine: dw: platform: power on device on  shutdown Andy Shevchenko <andriy.shevchenko@linux.intel.com> - 2015-11-26 19:10 +0100
          Re: [PATCH v2 5/7] dmaengine: dw: platform: power on device on  shutdown "Shevchenko, Andriy" <andriy.shevchenko@intel.com> - 2015-11-26 19:20 +0100

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