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Date:      Wed, 3 Aug 2016 20:52:42 +0000
From:      "Brian McGovern (bmcgover)" <bmcgover@cisco.com>
To:        "freebsd-arm@freebsd.org" <freebsd-arm@freebsd.org>
Subject:   Beaglebone Black ADC with 11-BETAs?
Message-ID:  <91547185801847a4951c4456d9d1dfb2@XCH-RTP-005.cisco.com>

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Its been 6+ months since I've worked with a BBB and the analog inputs. "Bac=
k in the day", I used the interface as described by ti_adc(4) man page. How=
ever, the last couple of days, I've built up an image using the code that i=
s on the 11.0 release path. The problem I'm seeing is that the ADC controll=
er appear to be disabled in this builds...

root@beaglebone:~ # dmesg | grep adc
ti_adc0: <TI ADC controller> mem 0x44e0d000-0x44e0dfff disabled on simplebu=
s0
ti_adc0: scheme: 0x1 func: 0x730 rtl: 0 rev: 0.1 custom rev: 0


... and the sysctl interface seems to be similarly truncated....

root@beaglebone:~ # sysctl -a | grep adc
dev.ti_adc.0.clockdiv: 2400
dev.ti_adc.0.%parent: simplebus0
dev.ti_adc.0.%pnpinfo: name=3Dtscadc@44e0d000 compat=3Dti,am3359-tscadc
dev.ti_adc.0.%location:=20
dev.ti_adc.0.%driver: ti_adc
dev.ti_adc.0.%desc: TI ADC controller
dev.ti_adc.%parent:=20

I noticed in the /boot/msdos/bboneblk.dts file that tscadc@44e0d000 had a s=
tatus =3D "disabled". I changed it to "okay" per other nodes, recompiled it=
 to bboneblk.dtb via dtc, rebooted, and still no joy.

Is the boot process using these files, or is the device tree built in to th=
e kernel (meaning I have to make fixes elsewhere and re-run the build)?=



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