[alsa-devel] [PATCH] ALSA: firewire-motu: remove invalid bitshift for register value

Takashi Sakamoto o-takashi at sakamocchi.jp
Mon Apr 3 14:13:50 CEST 2017


In protocol version 3, drivers can read current sampling clock status from
register 0x'ffff'f000'0b14. 8 bits of LSB of this register represents type
of signal as source of clock.

Current driver code includes invalid bitshift to handle the parameter. This
commit fixes the bug.

Reported-by: Dan Carpenter <dan.carpenter at oracle.com>
Fixes: 5992e30034c4 ("ALSA: firewire-motu: add support for MOTU 828mk3 (FireWire/Hybrid) as a model with protocol version 3")
Signed-off-by: Takashi Sakamoto <o-takashi at sakamocchi.jp>
---
 sound/firewire/motu/motu-protocol-v3.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/sound/firewire/motu/motu-protocol-v3.c b/sound/firewire/motu/motu-protocol-v3.c
index b463da9..ddb6472 100644
--- a/sound/firewire/motu/motu-protocol-v3.c
+++ b/sound/firewire/motu/motu-protocol-v3.c
@@ -14,7 +14,6 @@
 #define  V3_CLOCK_RATE_MASK		0x0000ff00
 #define  V3_CLOCK_RATE_SHIFT		8
 #define  V3_CLOCK_SOURCE_MASK		0x000000ff
-#define  V3_CLOCK_SOURCE_SHIFT		8
 
 #define V3_OPT_IFACE_MODE_OFFSET	0x0c94
 #define  V3_ENABLE_OPT_IN_IFACE_A	0x00000001
@@ -101,7 +100,7 @@ static int v3_get_clock_source(struct snd_motu *motu,
 		return err;
 	data = be32_to_cpu(reg);
 
-	val = (data & V3_CLOCK_SOURCE_MASK) >> V3_CLOCK_SOURCE_SHIFT;
+	val = data & V3_CLOCK_SOURCE_MASK;
 	if (val == 0x00) {
 		*src = SND_MOTU_CLOCK_SOURCE_INTERNAL;
 	} else if (val == 0x01) {
-- 
2.9.3



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