On 01/07/15 17:08, Jean-Francois Moine wrote:
On Wed, 07 Jan 2015 14:39:13 +0000 Andrew Jackson Andrew.Jackson@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