dmaengine: k3dma: Use vchan_terminate_vdesc() instead of desc_free

To avoid race with vchan_complete, use the race free way to terminate
running transfer.

Implement the device_synchronize callback to make sure that the terminated
descriptor is freed.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Acked-by: Zhangfei Gao <zhangfei.gao@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
diff --git a/drivers/dma/k3dma.c b/drivers/dma/k3dma.c
index 01d2a75..26b6745 100644
--- a/drivers/dma/k3dma.c
+++ b/drivers/dma/k3dma.c
@@ -719,7 +719,7 @@
 		c->phy = NULL;
 		p->vchan = NULL;
 		if (p->ds_run) {
-			k3_dma_free_desc(&p->ds_run->vd);
+			vchan_terminate_vdesc(&p->ds_run->vd);
 			p->ds_run = NULL;
 		}
 		p->ds_done = NULL;
@@ -730,6 +730,13 @@
 	return 0;
 }
 
+static void k3_dma_synchronize(struct dma_chan *chan)
+{
+	struct k3_dma_chan *c = to_k3_chan(chan);
+
+	vchan_synchronize(&c->vc);
+}
+
 static int k3_dma_transfer_pause(struct dma_chan *chan)
 {
 	struct k3_dma_chan *c = to_k3_chan(chan);
@@ -868,6 +875,7 @@
 	d->slave.device_pause = k3_dma_transfer_pause;
 	d->slave.device_resume = k3_dma_transfer_resume;
 	d->slave.device_terminate_all = k3_dma_terminate_all;
+	d->slave.device_synchronize = k3_dma_synchronize;
 	d->slave.copy_align = DMAENGINE_ALIGN_8_BYTES;
 
 	/* init virtual channel */