dmaengine: sh: rz-dmac: Fix destination and source data size setting

commit c6ec8c8 upstream.

Before setting DDS and SDS values, we need to clear its value first
otherwise, we get incorrect results when we change/update the DMA bus
width several times due to the 'OR' expression.

Fixes: 5000d37 ("dmaengine: sh: Add DMAC driver for RZ/G2L SoC")
Cc: stable@kernel.org
Signed-off-by: Hien Huynh <hien.huynh.px@renesas.com>
Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/20230706112150.198941-3-biju.das.jz@bp.renesas.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/dma/sh/rz-dmac.c

@@ -9,6 +9,7 @@
  * Copyright 2012 Javier Martin, Vista Silicon <javier.martin@vista-silicon.com>
  */
 
+#include <linux/bitfield.h>
 #include <linux/dma-mapping.h>
 #include <linux/dmaengine.h>
 #include <linux/interrupt.h>
@@ -145,8 +146,8 @@ struct rz_dmac {
 #define CHCFG_REQD			BIT(3)
 #define CHCFG_SEL(bits)			((bits) & 0x07)
 #define CHCFG_MEM_COPY			(0x80400008)
-#define CHCFG_FILL_DDS(a)		(((a) << 16) & GENMASK(19, 16))
-#define CHCFG_FILL_SDS(a)		(((a) << 12) & GENMASK(15, 12))
+#define CHCFG_FILL_DDS_MASK		GENMASK(19, 16)
+#define CHCFG_FILL_SDS_MASK		GENMASK(15, 12)
 #define CHCFG_FILL_TM(a)		(((a) & BIT(5)) << 22)
 #define CHCFG_FILL_AM(a)		(((a) & GENMASK(4, 2)) << 6)
 #define CHCFG_FILL_LVL(a)		(((a) & BIT(1)) << 5)
@@ -607,13 +608,15 @@ static int rz_dmac_config(struct dma_chan *chan,
 	if (val == CHCFG_DS_INVALID)
 		return -EINVAL;
 
-	channel->chcfg |= CHCFG_FILL_DDS(val);
+	channel->chcfg &= ~CHCFG_FILL_DDS_MASK;
+	channel->chcfg |= FIELD_PREP(CHCFG_FILL_DDS_MASK, val);
 
 	val = rz_dmac_ds_to_val_mapping(config->src_addr_width);
 	if (val == CHCFG_DS_INVALID)
 		return -EINVAL;
 
-	channel->chcfg |= CHCFG_FILL_SDS(val);
+	channel->chcfg &= ~CHCFG_FILL_SDS_MASK;
+	channel->chcfg |= FIELD_PREP(CHCFG_FILL_SDS_MASK, val);
 
 	return 0;
 }