[PATCH v2 1/2] dmaengine: at_hdmac: Repair bitfield macros for peripheral ID handling

[Peter Rosin]

The MSB part of the peripheral IDs need to go into the ATC_SRC_PER_MSB
and ATC_DST_PER_MSB fields. Not the LSB part.

This fixes a severe regression for TSE-850 devices (compatible
axentia,tse850v3) where output to the audio I2S codec (the main
purpose of the device) simply do not work.

Fixes: d8840a7edcf0 ("dmaengine: at_hdmac: Use bitfield access macros")
Cc: stable at vger.kernel.org
Signed-off-by: Peter Rosin <peda at axentia.se>
---
 drivers/dma/at_hdmac.c | 15 +++++++++------
 1 file changed, 9 insertions(+), 6 deletions(-)

diff --git a/drivers/dma/at_hdmac.c b/drivers/dma/at_hdmac.c
index 8858470246e1..6362013b90df 100644
--- a/drivers/dma/at_hdmac.c
+++ b/drivers/dma/at_hdmac.c
@@ -153,8 +153,6 @@
 #define ATC_AUTO		BIT(31)		/* Auto multiple buffer tx enable */
 
 /* Bitfields in CFG */
-#define ATC_PER_MSB(h)	((0x30U & (h)) >> 4)	/* Extract most significant bits of a handshaking identifier */
-
 #define ATC_SRC_PER		GENMASK(3, 0)	/* Channel src rq associated with periph handshaking ifc h */
 #define ATC_DST_PER		GENMASK(7, 4)	/* Channel dst rq associated with periph handshaking ifc h */
 #define ATC_SRC_REP		BIT(8)		/* Source Replay Mod */
@@ -181,10 +179,15 @@
 #define ATC_DPIP_HOLE		GENMASK(15, 0)
 #define ATC_DPIP_BOUNDARY	GENMASK(25, 16)
 
-#define ATC_SRC_PER_ID(id)	(FIELD_PREP(ATC_SRC_PER_MSB, (id)) |	\
-				 FIELD_PREP(ATC_SRC_PER, (id)))
-#define ATC_DST_PER_ID(id)	(FIELD_PREP(ATC_DST_PER_MSB, (id)) |	\
-				 FIELD_PREP(ATC_DST_PER, (id)))
+#define ATC_PER_MSB		GENMASK(5, 4)	/* Extract MSBs of a handshaking identifier */
+#define ATC_SRC_PER_ID(id)					       \
+	({ typeof(id) _id = (id);				       \
+	   FIELD_PREP(ATC_SRC_PER_MSB, FIELD_GET(ATC_PER_MSB, _id)) |  \
+	   FIELD_PREP(ATC_SRC_PER, _id); })
+#define ATC_DST_PER_ID(id)					       \
+	({ typeof(id) _id = (id);				       \
+	   FIELD_PREP(ATC_DST_PER_MSB, FIELD_GET(ATC_PER_MSB, _id)) |  \
+	   FIELD_PREP(ATC_DST_PER, _id); })
 
 
 
-- 
2.20.1