Hello everyone, I just subscribed to this list...
At Tue, 27 Jan 2004 07:14:40 -0800,
Martin J. Bligh wrote:
>>
>> Is there a reason to keep mmap_valid=0 in cs46xx driver or is this a real bug? I
>> haven't seen any new bugs with this patch applied, all the multimedia
>> applications (mplayer, xine, xmms, noatun) keeps on working.
> cs46xx doesn't always support the direct hardware buffer.
> Only in some cases with a proper period (fragment) numbers, it can
> support the direct buffer access. mmap_valid option forces the driver
> to allow OSS apps the direct accessing via mmap. This might not work
> always, depending on the parameter the app uses. Use at your own
> risk.
>
> In short: it's not a real bug as long as mmap_valid=1 option works.
> You had luck that your OSS apps (using mmap) seem working :)
If this is the case and if there are other applications affected by this
than Enemy Territory and Wine mentioned in bug #1959, maybe the
"use mmap_valid 0/1" option should made selectable by the user in
kernel menuconfig? Of course with the proper "Caution: selecting
mmap_valid may cure some applications while hurting the others" warnings
attached.
I mean, for example I thought for a long time that cs46xx is much more
badly broken in kernel 2.[56].x than it in reality seems to be. No new
sound bugs ever since I've applied this mmap_valid 0-->1 patch and I
think the first time I patched the driver was around 2.6.0-test1.
The sound card I have is Hercules SoundFusion Fortissimo III 7.1
(or something like that).
At Thu, 29 Jan 2004 08:56:55 +0200,
Janne Pikkarainen wrote:
>
> Hello everyone, I just subscribed to this list...
>
> At Tue, 27 Jan 2004 07:14:40 -0800,
> Martin J. Bligh wrote:
> >>
> >> Is there a reason to keep mmap_valid=0 in cs46xx driver or is this a real bug? I
> >> haven't seen any new bugs with this patch applied, all the multimedia
> >> applications (mplayer, xine, xmms, noatun) keeps on working.
>
> > cs46xx doesn't always support the direct hardware buffer.
> > Only in some cases with a proper period (fragment) numbers, it can
> > support the direct buffer access. mmap_valid option forces the driver
> > to allow OSS apps the direct accessing via mmap. This might not work
> > always, depending on the parameter the app uses. Use at your own
> > risk.
> >
> > In short: it's not a real bug as long as mmap_valid=1 option works.
> > You had luck that your OSS apps (using mmap) seem working :)
>
> If this is the case and if there are other applications affected by this
> than Enemy Territory and Wine mentioned in bug #1959, maybe the
> "use mmap_valid 0/1" option should made selectable by the user in
> kernel menuconfig? Of course with the proper "Caution: selecting
> mmap_valid may cure some applications while hurting the others" warnings
> attached.
>
> I mean, for example I thought for a long time that cs46xx is much more
> badly broken in kernel 2.[56].x than it in reality seems to be. No new
> sound bugs ever since I've applied this mmap_valid 0-->1 patch and I
> think the first time I patched the driver was around 2.6.0-test1.
>
> The sound card I have is Hercules SoundFusion Fortissimo III 7.1
> (or something like that).
i myself have no objection to change the default for this option.
there are no many apps which use OSS mmap, except for quake & co. and
wine.
OTOH, i also feel that putting a single line in /etc/modprobe.conf
wouldn't be a hard job...
--
Takashi Iwai <[email protected]> ALSA Developer - http://www.alsa-project.org