dmaengine: xilinx_dma: Fix control reg update in vdma_channel_set_config

In vdma_channel_set_config clear the delay, frame count and master mask
before updating their new values. It avoids programming incorrect state
when input parameters are different from default.

Signed-off-by: Radhey Shyam Pandey <radhey.shyam.pandey@xilinx.com>
Acked-by: Appana Durga Kedareswara rao <appana.durga.rao@xilinx.com>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Link: https://lore.kernel.org/r/1569495060-18117-3-git-send-email-radhey.shyam.pandey@xilinx.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>

drivers/dma/xilinx/xilinx_dma.c

@@ -68,6 +68,9 @@
 #define XILINX_DMA_DMACR_CIRC_EN		BIT(1)
 #define XILINX_DMA_DMACR_RUNSTOP		BIT(0)
 #define XILINX_DMA_DMACR_FSYNCSRC_MASK		GENMASK(6, 5)
+#define XILINX_DMA_DMACR_DELAY_MASK		GENMASK(31, 24)
+#define XILINX_DMA_DMACR_FRAME_COUNT_MASK	GENMASK(23, 16)
+#define XILINX_DMA_DMACR_MASTER_MASK		GENMASK(11, 8)
 
 #define XILINX_DMA_REG_DMASR			0x0004
 #define XILINX_DMA_DMASR_EOL_LATE_ERR		BIT(15)
@@ -2118,8 +2121,10 @@ int xilinx_vdma_channel_set_config(struct dma_chan *dchan,
 	chan->config.gen_lock = cfg->gen_lock;
 	chan->config.master = cfg->master;
 
+	dmacr &= ~XILINX_DMA_DMACR_GENLOCK_EN;
 	if (cfg->gen_lock && chan->genlock) {
 		dmacr |= XILINX_DMA_DMACR_GENLOCK_EN;
+		dmacr &= ~XILINX_DMA_DMACR_MASTER_MASK;
 		dmacr |= cfg->master << XILINX_DMA_DMACR_MASTER_SHIFT;
 	}
 
@@ -2135,11 +2140,13 @@ int xilinx_vdma_channel_set_config(struct dma_chan *dchan,
 	chan->config.delay = cfg->delay;
 
 	if (cfg->coalesc <= XILINX_DMA_DMACR_FRAME_COUNT_MAX) {
+		dmacr &= ~XILINX_DMA_DMACR_FRAME_COUNT_MASK;
 		dmacr |= cfg->coalesc << XILINX_DMA_DMACR_FRAME_COUNT_SHIFT;
 		chan->config.coalesc = cfg->coalesc;
 	}
 
 	if (cfg->delay <= XILINX_DMA_DMACR_DELAY_MAX) {
+		dmacr &= ~XILINX_DMA_DMACR_DELAY_MASK;
 		dmacr |= cfg->delay << XILINX_DMA_DMACR_DELAY_SHIFT;
 		chan->config.delay = cfg->delay;
 	}