From: Dmitry Osipenko <digetx@gmail.com>
Date: Sun, 9 Feb 2020 19:33:40 +0300
Subject: dmaengine: tegra-apb: Implement synchronization hook

Git-commit: dda5e35a771043bb5a9e6107fa9f141d8d56b847
Patch-mainline: v5.7-rc1
References: jsc#SLE-15847

The ISR tasklet could be kept scheduled after DMA transfer termination,
let's add synchronization hook which blocks until tasklet is finished.

Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Acked-by: Jon Hunter <jonathanh@nvidia.com>
Link: https://lore.kernel.org/r/20200209163356.6439-4-digetx@gmail.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Mian Yousaf Kaukab <yousaf.kaukab@suse.com>
---
 drivers/dma/tegra20-apb-dma.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/drivers/dma/tegra20-apb-dma.c b/drivers/dma/tegra20-apb-dma.c
index 3a45079d11ec..b18cbfbab004 100644
--- a/drivers/dma/tegra20-apb-dma.c
+++ b/drivers/dma/tegra20-apb-dma.c
@@ -802,6 +802,13 @@ static int tegra_dma_terminate_all(struct dma_chan *dc)
 	return 0;
 }
 
+static void tegra_dma_synchronize(struct dma_chan *dc)
+{
+	struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc);
+
+	tasklet_kill(&tdc->tasklet);
+}
+
 static unsigned int tegra_dma_sg_bytes_xferred(struct tegra_dma_channel *tdc,
 					       struct tegra_dma_sg_req *sg_req)
 {
@@ -1510,6 +1517,7 @@ static int tegra_dma_probe(struct platform_device *pdev)
 	tdma->dma_dev.residue_granularity = DMA_RESIDUE_GRANULARITY_BURST;
 	tdma->dma_dev.device_config = tegra_dma_slave_config;
 	tdma->dma_dev.device_terminate_all = tegra_dma_terminate_all;
+	tdma->dma_dev.device_synchronize = tegra_dma_synchronize;
 	tdma->dma_dev.device_tx_status = tegra_dma_tx_status;
 	tdma->dma_dev.device_issue_pending = tegra_dma_issue_pending;
 
-- 
2.26.2