B) the I2C commands to the CODEC set DSP mode, not IIS mode Because the default codec is doing 2 channel TDM, not 2 channel i2s.
A) the McASP pins never do anything You have looked at the pins on an analyzer? On Sun, Sep 27, 2015 at 10:12 PM, Rick Mann <[email protected]> wrote: > I built a cape using the same codec as the BB Audio Cape Rev B > (tlv320aic3104) =, and wired it up the same way to reduce the amount of > Linux configuration I'd have to do to get it to work. I finally have it > communicating over the i2c bus, and both the codec and the alsa sound card > seem to be (mostly) properly configured in the device tree overlay ( > https://github.com/JetForMe/podtique/blob/v1/bbb/cape/Podtique1/BB-ENABLE-PRU.dts > ). > > But the McASP part of the interface still seems to do nothing. Looking at > the pins with an oscilloscope, nothing comes out. I *think* I'm at a point > where my ALSA configuration is wrong, but I'm not sure. > > Lending further credence to the ALSA config culprit theory is the fact > that the i2c commands to configure the codec seem to be incorrect. In > particular, when I run "speaker-test", the i2c commands that get sent to > the codec set it up for DSP mode, not IIS/I2S mode. The DT overlay calls > for IIS mode. > > Other parts of the DT overlay seem to be working very well. Linux enables > the power regulators for the CODEC via a GPIO, and takes it out of reset > via another GPIO before communicating with it. I watched the I2C traffic > with an I2C protocol analyzer, and it looks solid (you can see it here. The > first part is the cape enumeration, the codec comms start at transaction > 49: http://pastebin.com/2VFPVBbq). > > On my board, I've got the differential line out L&R going to an on-board > audio power amp. I haven't routed any of the other outputs (or inputs) from > the CODEC. > > Anyone got any insight as to why > > A) the McASP pins never do anything > B) the I2C commands to the CODEC set DSP mode, not IIS mode > > Thanks! > > -- > Rick Mann > [email protected] > > > -- > For more options, visit http://beagleboard.org/discuss > --- > You received this message because you are subscribed to the Google Groups > "BeagleBoard" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > For more options, visit https://groups.google.com/d/optout. > -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups "BeagleBoard" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/d/optout.
