From mboxrd@z Thu Jan  1 00:00:00 1970
From: cedric.madianga@gmail.com (M'boumba Cedric Madianga)
Date: Wed, 14 Oct 2015 15:17:14 +0200
Subject: [PATCH v2 2/4] dmaengine: Add STM32 DMA driver
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To: linux-arm-kernel@lists.infradead.org
List-Id: linux-arm-kernel.lists.infradead.org

Hi Daniel,

>>> +
>>> +static int stm32_dma_remove(struct platform_device *pdev)
>>> +{
>>> +       struct stm32_dma_device *dmadev = platform_get_drvdata(pdev);
>>> +
>>> +       of_dma_controller_free(pdev->dev.of_node);
>>> +
>>> +       dma_async_device_unregister(&dmadev->ddev);
>>> +
>>> +       clk_disable_unprepare(dmadev->clk);
>>
>>
>> What is the purpose of disabling/unpreparing the clock here?
>> stm32_dma_alloc_chan_resources() and stm32_dma_free_chan_resources() should
>> pair up and the clock should already be stopped.

stm32_dma_remove() could be called during an on-going transfer during
module unload.
So in that case, it seems that disabling/unpreparing the clock is needed.

BR,
Cedric