2007-11-29 18:19:49

by Roel Kluin

Subject: [PATCH?] OSS: fix operator precedence in return of btaudio_dsp_ioctl

First of all, is /sound/oss/* still maintained?

#define HWBASE_AD (448000)
...
with if(bta->analog) evaluating to true bta->decimation may range
from 15 to 5
...
HWBASE_AD*4/bta->decimation>>bta->sampleshift

which is equivalent to

((HWBASE_AD * 4)/bta->decimation) >> bta->sampleshift

actually may evaluate to something like:

(1792000 / 15 ) >> bta->sampleshift

Isn't intended (HWBASE_AD * 4)/(bta->decimation >> bta->sampleshift)?
Then consider the patch below.
--
Fix operator precedence in return

Signed-off-by: Roel Kluin <[email protected]>
---
diff --git a/sound/oss/btaudio.c b/sound/oss/btaudio.c
index 4d5cf05..2a5cace 100644
--- a/sound/oss/btaudio.c
+++ b/sound/oss/btaudio.c
@@ -661,7 +661,8 @@ static int btaudio_dsp_ioctl(struct inode *inode, struct file *file,
/* fall through */
case SOUND_PCM_READ_RATE:
if (bta->analog) {
- return put_user(HWBASE_AD*4/bta->decimation>>bta->sampleshift, p);
+ return put_user((HWBASE_AD * 4) /
+ (bta->decimation >> bta->sampleshift), p);
} else {
return put_user(bta->rate, p);
}

2007-11-29 18:59:54

by Tomas Carnecky

Subject: Re: [PATCH?] OSS: fix operator precedence in return of btaudio_dsp_ioctl

Roel Kluin wrote:
> First of all, is /sound/oss/* still maintained?
>

Documentation/feature-removal-schedule.txt

What: drivers depending on OSS_OBSOLETE
When: options in 2.6.23, code in 2.6.25
Why: obsolete OSS drivers
Who: Adrian Bunk <[email protected]>

tom

2007-11-29 20:30:32

by Adrian Bunk

Subject: Re: [PATCH?] OSS: fix operator precedence in return of btaudio_dsp_ioctl

On Thu, Nov 29, 2007 at 07:59:26PM +0100, Tomas Carnecky wrote:
> Roel Kluin wrote:
> > First of all, is /sound/oss/* still maintained?
> >
>
> Documentation/feature-removal-schedule.txt
>
> What: drivers depending on OSS_OBSOLETE
> When: options in 2.6.23, code in 2.6.25
> Why: obsolete OSS drivers
> Who: Adrian Bunk <[email protected]>

I'm maintaining only the gradual removal. ;-)

That's only the removal of some of the remaining OSS drivers, but
btaudio is among them.

> tom

cu
Adrian

--

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of the darkness. There had been need of rain for many days.
"Only a promise," Lao Er said.
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