[alsa-devel] idt blue jack patch

[Takashi Iwai]

At Sat, 21 Feb 2009 09:42:14 +0800,
Wu Fengguang wrote:
> 
> On Fri, Feb 20, 2009 at 07:18:31PM +0200, Takashi Iwai wrote:
> > At Fri, 20 Feb 2009 09:00:01 +0800,
> > Wu Fengguang wrote:
> > > 
> > > Hi Tobin,
> > > 
> > > Here are the Linux and WinXP pin configurations.
> > > Both Linux and WinXP configure node 0x0c as an output pin.
> > > 
> > > However the driver seems to be offering three schemes:
> > > 
> > >         scheme desc             0xC dev
> > > ------------------------------------------------------
> > >         IDS_CONFIG_OPEN         Speaker_Side/LineIn
> > >         IDS_CONFIG_51           LineIn
> > >         IDS_CONFIG_71           Speaker_Side
> > > 
> > > Paulo, maybe you can run these commands to switch between
> > > linein/lineout modes:
> > > 
> > >         # wget http://www.kernel.org/pub/linux/kernel/people/tiwai/misc/hda-verb-0.3.tar.bz2
> > > 
> > >         # set PIN_IN mode
> > >         hda-verb /dev/snd/hwC0D2 0x0c SET_PIN_WIDGET_CONTROL 0x20
> > > 
> > >         # set PIN_OUT mode
> > >         hda-verb /dev/snd/hwC0D2 0x0c SET_PIN_WIDGET_CONTROL 0x40
> > 
> > 
> > Regarding the default pin configurations.
> > I made a series of patches to add the interface to change the default
> > pincfg values dynamically via hwdep sysfs.  The patches are found in
> > test/hda-pincfg branch of sound git tree
> >     git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound-2.6.git
> > 
> > and included in the very latest alsa-driver-unstable snapshot
> >     ftp://ftp.kernel.org/pub/linux/kernel/people/tiwai/snapshot/alsa-driver-unstable-snapshot.tar.gz
> > 
> > Basically, you can get / set the default pincfg values on the fly, and
> > trigger the codec reconfiguration after that.
> > 
> > The init_pin_configs file shows the initial default pincfgs set by BIOS.
> > 
> > 	# cat /sys/class/sound/hwC0D0/init_pin_configs
> > 	0x14 0x9993013f
> > 	0x15 0x01014c10
> > 	0x16 0x99030120
> > 	0x18 0x01a19c30
> > 	0x19 0x02a11c31
> > 	0x1a 0x01813c32
> > 	0x1b 0x02211c1f
> > 	0x1c 0x99330133
> > 	0x1d 0x411111f0
> > 	0x1e 0x411111f0
> > 	0x1f 0x411111f0
> > 
> > Then, you can override the default value by writing to
> > override_pin_configs sysfs file.
> > 
> > 	# cat /sys/class/sound/hwC0D0/override_pin_configs
> > 	# echo 0x1d 0x02a11c30 > /sys/class/sound/hwC0D0/override_pin_configs
> > 	# cat /sys/class/sound/hwC0D0/override_pin_configs
> > 	0x1d 0x02a11c30
> > 
> > Note that this value won't appear in init_pin_configs.
> > 
> > Also, there is another file, cur_pin_configs.  This contains the
> > pincfgs that are set by the driver explicitly.  For example,
> > the static pincfg table in patch_sigmatel.c appears here.
> > 
> > Then you can trigger the codec reconfiguration by
> > 
> > 	# echo 1 > /sys/class/sound/hwC0D0/reconfig
> > 
> > This will re-setup the driver based on the given pin configs.
> 
> Cool!  This interface will greatly ease the developer-user interactions.
> 
> Without knowing this feature, I had to write a patch for Paulo,
> and compile/verify it before sending it to him. Paulo also have to
> pull the kernel source, apply the patch, compile and run it...
> 
> Now you turned that tedious process into two simple echo commands :-)
> 
> > Unfortunately, in the current scenario, it can't override the static
> > pincfg table in the driver like in patch_sigmatel.c.  It's just for
> > fixing and BIOS setup.
> 
> Unfortunately patch_sigmatel has a long list of static pincfgs, i.e.:
> 
>         static unsigned int ref927x_pin_configs[14] = {
>                 0x02214020, 0x02a19080, 0x0181304e, 0x01014010,
>                 0x01a19040, 0x01011012, 0x01016011, 0x0101201f,
>                 0x183301f0, 0x18a001f0, 0x18a001f0, 0x01442070,
>                 0x01c42190, 0x40000100,
>         };
> 
> This effectively prohibits itself from being dynamically reconfigured
> via the override_pin_configs interface... 

Right.  Considering the implementation again, I think it must be
relatively easy to fix that.  Just changing the order of the evaluation
of pincfg, and add the check not to overwrite the value.

I'll work on it in the next week.


Takashi