dmaengine: fsl-edma: kill the tasklets upon exit

drivers should ensure that tasklets are killed, so that they can't be
executed after driver remove is executed, so ensure they are killed.

This driver used vchan tasklets, so those need to be killed.

Signed-off-by: Vinod Koul <[e-mail]>
Cc: Jingchang Lu <[e-mail]>
Cc: Peter Griffin <[e-mail]>

drivers/dma/fsl-edma.c

···
 	return 0;
 }
 
+static void fsl_edma_cleanup_vchan(struct dma_device *dmadev)
+{
+	struct fsl_edma_chan *chan, *_chan;
+
+	list_for_each_entry_safe(chan, _chan,
+				&dmadev->channels, vchan.chan.device_node) {
+		list_del(&chan->vchan.chan.device_node);
+		tasklet_kill(&chan->vchan.task);
+	}
+}
+
 static int fsl_edma_remove(struct platform_device *pdev)
 {
 	struct device_node *np = pdev->dev.of_node;
 	struct fsl_edma_engine *fsl_edma = platform_get_drvdata(pdev);
 
 	fsl_edma_irq_exit(pdev, fsl_edma);
+	fsl_edma_cleanup_vchan(&fsl_edma->dma_dev);
 	of_dma_controller_free(np);
 	dma_async_device_unregister(&fsl_edma->dma_dev);
 	fsl_disable_clocks(fsl_edma);