On Sun, Aug 30, 2009 at 09:35:08PM -0400, Ryan Flannery wrote:
> On Sun, Aug 30, 2009 at 8:55 PM, Brynet<bry...@gmail.com> wrote:
> > Edd wrote:
> >> Upon invocation I get:
> >> xstatbar: ioctl AUDIO_MIXER_READ: Invalid argument
> >
> > The system I was using had no sound card.. I assumed this error was
> > related to that, so perhaps the author can tell us why it doesn't
> > work?
> >
> > Here is the cosmetic changes anyway, sorry for not properly testing.
> >
>
> Off-hand I have no idea why this fails, but I can dig into it further
> if it is still an open issue.
couple issues here ...
/* find the "master" device */
v->master_idx = -1;
devinfo.index = 0;
while (ioctl(v->dev_fd, AUDIO_MIXER_DEVINFO, &devinfo) >= 0)
{ if (strncmp(devinfo.label.name, "master", 7) == 0)
v->master_idx = devinfo.index;
devinfo.index++;
}
if (v->master_idx == -1)
errx(1, "failed to find \"master\" mixer device for volume init");
you should make sure you get outputs.master as opposed to possibly
record.master, or some other "master". technically speaking, a device
is free to make up whatever class it wants. you have to find the
"outputs" class index, and make sure that "master"'s mixer_class equals
the "outputs" class index.
/* Volume values are stored as 8-bit values, however not all values are
* supported (i.e. fewer than 256 different volume levels may be
* supported). As such, to accurately determine the percentages shown
* in the display, we have to find the maximum settings for this
* device.
you could use the delta: devinfo.un.v.delta. that is the step size
of the hardware. that is, you have to move that many volume units to
affect a change in the hardware. you could use this to determine
the largest value ...
So, we...
* 1. read the current volume values
* 2. set the volume to the max possible (255)
255 -> AUDIO_MAX_GAIN
* 3. read the volume values and see what the max is for this device
* 4. reset the volume to what was read in step 1 so we don't muck
* with the users' volume.
*/
/* read current volume */
v->info.dev = v->master_idx;
v->info.type = AUDIO_MIXER_VALUE;
if (ioctl(v->dev_fd, AUDIO_MIXER_READ, &(v->info)) < 0)
err(1, "ioctl AUDIO_MIXER_READ");
that fails because on many devices because num_channels is not set
correctly. in sys/dev/ic/ac97.c:
ac97_mixer_get_port(struct ac86_codec_if *codec_if, mixer_ctrl_t *cp)
{
struct ac97_softc *as = (struct ac97_softc *)codec_if;
struct ac97_source_info *si = &as->source_info[cp->dev];
...
case AUDIO_MIXER_VALUE:
{
const struct audio_mixer_value *value = si->info;
u_int16_t l, r;
if ((cp->un.value.num_channels <= 0) ||
(cp->un.value.num_channels > value->num_channels))
return (EINVAL);
here, value->num_channels == devinfo.un.v.num_channels ...
--
jake...@sdf.lonestar.org
SDF Public Access UNIX System - http://sdf.lonestar.org
