mmc: moxart: Fix issue with uninitialized dma_slave_config

stable inclusion
from stable-5.10.65
commit cfaefbcc6bc4c2bf76b9c9779cf6d6ff95a2fbac
bugzilla: 182361 https://gitee.com/openeuler/kernel/issues/I4EH3U

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=cfaefbcc6bc4c2bf76b9c9779cf6d6ff95a2fbac

--------------------------------

[ Upstream commit ee516535 ]

Depending on the DMA driver being used, the struct dma_slave_config may
need to be initialized to zero for the unused data.

For example, we have three DMA drivers using src_port_window_size and
dst_port_window_size. If these are left uninitialized, it can cause DMA
failures.

For moxart, this is probably not currently an issue but is still good to
fix though.

Fixes: 1b66e94e ("mmc: moxart: Add MOXA ART SD/MMC driver")
Cc: Jonas Jensen <jonas.jensen@gmail.com>
Cc: Vinod Koul <vkoul@kernel.org>
Cc: Peter Ujfalusi <peter.ujfalusi@gmail.com>
Signed-off-by: NTony Lindgren <tony@atomide.com>
Link: https://lore.kernel.org/r/20210810081644.19353-3-tony@atomide.comSigned-off-by: NUlf Hansson <ulf.hansson@linaro.org>
Signed-off-by: NSasha Levin <sashal@kernel.org>
Signed-off-by: NChen Jun <chenjun102@huawei.com>
Acked-by: NWeilong Chen <chenweilong@huawei.com>
Signed-off-by: NChen Jun <chenjun102@huawei.com>
Signed-off-by: NZheng Zengkai <zhengzengkai@huawei.com>

drivers/mmc/host/moxart-mmc.c

@@ -631,6 +631,7 @@ static int moxart_probe(struct platform_device *pdev)
 			 host->dma_chan_tx, host->dma_chan_rx);
 		host->have_dma = true;
 
+		memset(&cfg, 0, sizeof(cfg));
 		cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
 		cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;