[meta-freescale] minimal work to test headphone jack playing both channels on MCIMX6Q-SDB?

[Robert P. J. Day]

  for comparison purposes to figure out why a dev board doesn't play
anything on the right channel of the headphone jack, i want to do
nothing more than build a minimal YP bootable image for a stock
freescale MCIMX6Q-SDB and play a .wav file to verify that both
headphone channels work, then try to converge to what the problem is,
so here's what i did.

  i have fully-updated master branches of both poky and
meta-freescale, started a new project, with only these changes to
local.conf:

  MACHINE = "imx6qdlsabresd"
  IMAGE_INSTALL_append = " alsa-utils"

did the build on my fedora 26 system, got, uncompressed and dd'ed to
SD card the resulting "core-image-minimal-imx6qdlsabresd.sdcard" file
and booted from it ... now all i want is to do as little as possible
to verify that both headphone channels work. so at this point, the
question is ... given that the above is the *entirety* of what i've
done to boot my board, what do i need to do in terms of configuring
alsa-utils to play a simple .wav file on both headphone outputs?

  first, given that i've installed alsa-utils, i can see some sample
.wav files under /usr/share/sounds/alsa/:

-rw-r--r--    1 root     root        137134 Oct  2 14:53 Front_Center.wav
-rw-r--r--    1 root     root        142128 Oct  2 14:53 Front_Left.wav
-rw-r--r--    1 root     root        146990 Oct  2 14:53 Front_Right.wav
-rw-r--r--    1 root     root        135202 Oct  2 14:53 Noise.wav
-rw-r--r--    1 root     root        130096 Oct  2 14:53 Rear_Center.wav
-rw-r--r--    1 root     root        126064 Oct  2 14:53 Rear_Left.wav
-rw-r--r--    1 root     root        146480 Oct  2 14:53 Rear_Right.wav
-rw-r--r--    1 root     root        134868 Oct  2 14:53 Side_Left.wav
-rw-r--r--    1 root     root        129966 Oct  2 14:53 Side_Right.wav

at this point, i suspect i need to use "amixer" to configure the
onboard WM8962 codec just enough to hear a .wav file being played via
"aplay" over the headphones so, while i start messing with that, i'm
open to any advice as to how simple it is to just plug in some ear
buds and play a .wav file.

  oh, first question ... i'm assuming that playing a .wav file feeds
the digital file into the WM8962's digital audio interface, so at
least i know where i'm starting with the debugging process.

  thoughts?

rday

-- 

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Robert P. J. Day                                 Ottawa, Ontario, CANADA
                        http://crashcourse.ca

Twitter:                                       http://twitter.com/rpjday
LinkedIn:                               http://ca.linkedin.com/in/rpjday
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