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Porting AD1938 ALSA driver

Thread Summary

The user is facing challenges porting a customized AD1938 ALSA driver from 2011r1-rc3 to 2012R2-RC5, particularly with changes in the SPORT and bitbang SPI. The final answer suggests using the AD193x SOC driver and adding custom volume control using SOC_DOUBLE_EXT_TLV to manage the AD5204 soft pot for gain adjustment.
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I am trying to port a customized AD1938 ALSA driver from 2011r1-rc3 to 2012R2-RC5 and finding it rather challenging due to all of the changes (in sport, bitbang SPI, etc).  I am wondering if it would be better for me to drop the custom driver and start over with the AD193x driver (which apparently uses the SOC framework now).

One complication with switching is that the driver actually controls two chips, the AD1938 itself and a AD5204 soft pot which is used to control the gain of the audio feeding the AD1938 (making it present similar ALSA "volume" controls to the AD1936 which has that gain control built in).  So it controls two bitbanged SPI devices.  The SOC AD193x driver is very different from what I am used to.  Is there a reasonable way to make such a driver now?  Or should I quit using the ALSA controls to adjust the input audio gain and modify the applications to use a new method?

Any suggestions would be very welcome.  Thanks.

Steve