On 01/07/15 17:08, Jean-Francois Moine wrote: > On Wed, 07 Jan 2015 14:39:13 +0000 > Andrew Jackson <Andrew.Jackson@xxxxxxx> 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 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
