On 01/07/15 17:08, Jean-Francois Moine wrote:
> On Wed, 07 Jan 2015 14:39:13 +0000
> Andrew Jackson <Andrew.Jackson at arm.com> wrote:
>
>>> + - audio-ports: must contain one or two values selecting the source
>>> + in the audio port.
>>> + The source type is given by the corresponding entry in
>>> + the audio-port-names property.
>>
>> I think that this entry might benefit from a little more explanation.
>> The value specified here selects which pins on the chip provide the
>> audio input doesn't it? In the outline datasheet that I have these are
>> listed in table 17:
>>
>> Audio port Input configuration
>> S/PDIF I2S-bus
>> AP0 - WS (word select)
>> AP1 S/PDIF input I2S-bus channel 0
>> AP2 S/PDIF input I2S-bus channel 1
>> AP3[1] I2S-bus channel 2
>> AP4[1] I2S-bus channel 3
>> ACLK - SCK (I2S-bus clock)
>>
>> [1] Depending on package.
>
> Your table is close to the one in the TDA9983B documentation I have,
> but the pins are not exactly the same:
>
> AP0 WS (word select)
> AP1 I2S-bus port 0
> AP2 I2S-bus port 1
> AP3 I2S-bus port 2
> AP4 I2S-bus port 3
> AP5 MCLK (master clock for S/PDIF)
> AP6 S/PDIF input
> AP7 AUX (internal test)
> ACLK SCK (I2S-bus clock)
>
> That's why I did not know clearly why I had to set AP2 for S/PDIF input
> and (AP0 + AP1) for I2S input in the Cubox.
>
> Then, the only more explanation I could give is "have a look at the
> audio input format and at the register 0x1e page 0 in the documentation
> of the TDA998x chip".
>
> BTW, the tda998x driver supports only the TDA9989, TDA19988 and
> TDA19989 chips. If the TDA9983B would be supported, the audio port
> definitions would be of no use.
>
> So, what would you see as an explanation?
>
I understand your difficulty! I was just wanting something to clarify the
meaning of the value without reference to the driver source.
You could add something like this to your existing explanation: "The value
describes which audio input pins are selected; this varies depending
on chip type so consult the section on audio port configuration in the
relevant datasheet.".
Andrew
