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

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

[Takashi Sakamoto]

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@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@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

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

[Takashi Iwai]

On Mon, 03 Apr 2017 14:13:50 +0200,
Takashi Sakamoto wrote:
> 
> 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@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@sakamocchi.jp>

Applied to for-next branch now.  Thanks.


Takashi

> ---
>  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
>