On 02/05/2014 07:07 PM, Jean-Francois Moine wrote:
> On Wed, 05 Feb 2014 10:19:22 +0100
> Lars-Peter Clausen <lars at metafoo.de> wrote:
>
>>> So, in the CODEC, I don't see how I could update the parameters
>>> dictated by the EDID otherwise in changing the DAI driver parameters.
>>>
>>
>> The startup function is the right place. But instead of modifying the DAI
>> use snd_pcm_hw_constraint_mask64(), snd_pcm_hw_constraint_list(), etc. to
>> setup the additional constraints that come from the EDID.
>
> It is more complicated, but it works. Nevertheless, I have 2 problems:
>
> - snd_pcm_hw_constraint_list() keeps a pointer to the list, so, it
> cannot be in the stack. It fix this with static struct and rate array.
>
Right. If the struct is modified though it should be per device and not
global. I think the best way to implement this is to make the array static
and specify a mask for the constraint based on the EDID. E.g.
static unsigned int hdmi_rates[] = {
32000,
44100,
48000,
88200,
96000,
176400,
192000,
};
rate_mask = 0;
while (...) {
...
rate_mask |= 1 << sad[1];
}
rate_constraints->list = hdmi_rates;
rate_constraints->count = ARRAY_SIZE(hdmi_rates);
rate_constraints->mask = rate_mask;
> - snd_pcm_hw_constraint_mask64() is not exported.
> Is there an other way to set constraints on the formats/sample widths?
I think that's a bug. Both snd_pcm_hw_constraint_mask() and
snd_pcm_hw_constraint_mask64() should be exported. Can you send a patch?
- Lars
