(Also made this post here on the BB Google group.)
If I just tap the power button on the BeagleBone Black Wireless, it immediately begins the shutdown sequence. We need to avoid that behavior; it seems the way to do so is to disable the PB-state change IRQ (from the TPS65217 datasheet):
8.6.4 Interrupt Register (INT) (Address = 0x02) [reset = 0x80]
Bit 6: PBM R/W 0b = Interrupt is issued when PB status changes.
Bit 6: PBM R/W 1b = No interrupt is issued when PB status changes.
The bit is cleared:
i2cget -f -y 0 0x24 0x2
0x20
A similar post from 2017 didn’t really seem to have a resolution:
“Disabling PowerOff and Reset button” https://groups.google.com/g/beagleboard/c/4qv0osguaDI/m/0ITntryPAQAJ
I’ve followed a similar path, outlined in more detail below, without being able to disable the PB IRQ, either.
Thanks for any assistance.
The hardware is a BBBW with a 4D Systems gen4 cape and LCD.
$ uname -a
Linux beaglebone 4.19.94-ti-r43 #1buster SMP PREEMPT Wed Apr 22 06:11:16 UTC 2020 armv7l GNU/Linux
-
start with RCN’s DT repo:
-
git clone https://github.com/beagleboard/BeagleBoard-DeviceTrees -
pushd ~/BeagleBoard-DeviceTrees -
fgrep -rni . -e 'tps65217-pwrbutton'
./src/arm/tps65217.dtsi:27: compatible = "ti,tps65217-pwrbutton"; -
nano ./src/arm/tps65217.dtsi
comment out thepwrbuttonnode/* pwrbutton { compatible = "ti,tps65217-pwrbutton"; interrupts = <2>; status = "disabled"; }; */ -
Note that it doesn’t matter if the above file is modified, or the one below, or both. In no case is the PB IRQ disabled.
-
edit the common BB file,
am335x-bone-common.dtsi, to disable thepwrbutton -
pushd ~/BeagleBoard-DeviceTrees -
nano -l ./src/arm/am335x-bone-common.dtsi -
the line to edit is ~365
-
change status from
okaytodisabled:
pwrbutton {
status = "disabled";
};
-
build the dtb files:
make -
back up the current dtb file, then copy the new dtb file
debian@beaglebone:~/BeagleBoard-DeviceTrees$ sudo mv /boot/dtbs/4.19.94-ti-r43/am335x-boneblack-wireless.dtb /boot/dtbs/4.19.94-ti-r43/am335x-boneblack-wireless.bak.dtb debian@beaglebone:~/BeagleBoard-DeviceTrees$ sudo cp ./src/arm/am335x-boneblack-wireless.dtb /boot/dtbs/4.19.94-ti-r43/am335x-boneblack-wireless.dtb -
Compare the resulting dtb file with the original:
-
the entire
pwrbuttonsection commented out intps65217.dtsi -
pwrbuttonset todisabledinam335x-bone-common.dtsi
```
$ dtdiff /boot/dtbs/4.19.94-ti-r43/am335x-boneblack-wireless.bak.dtb /boot/dtbs/4.19.94-ti-r43/am335x-boneblack-wireless.dtb
--- /dev/fd/63 2020-10-28 02:56:38.720410323 +0000
+++ /dev/fd/62 2020-10-28 02:56:38.720410323 +0000
@@ -280,7 +280,7 @@
chosen {
base_dtb = "am335x-boneblack-wireless.dts";
- base_dtb_timestamp = "Wed Apr 22 06:09:34 2020";
+ base_dtb_timestamp = "Tue Oct 27 19:48:20 2020";
stdout-path = "/ocp/serial@44e09000";
};
@@ -851,9 +851,7 @@
};
pwrbutton {
- compatible = "ti,tps65217-pwrbutton";
- interrupts = < 0x02 >;
- status = "okay";
+ status = "disabled";
};
regulators {
```
-
based on boot-up messages from serial port
... debug: [enable_uboot_cape_universal=1] ... debug: [uboot_base_dtb_univ=am335x-boneblack-uboot-univ.dtb] ... uboot_overlays: [uboot_base_dtb=am335x-boneblack-uboot-univ.dtb] ... uboot_overlays: Switching too: dtb=am335x-boneblack-uboot-univ.dtb ... loading /boot/dtbs/4.19.94-ti-r43/am335x-boneblack-uboot-univ.dtb ... ...I copied
am335x-boneblack-uboot-univ.dtbinstead ofam335x-boneblack-wireless.dtb(already built, above) -
pushd ~/BeagleBoard-DeviceTrees -
sudo mv /boot/dtbs/4.19.94-ti-r43/am335x-boneblack-uboot-univ.dtb /boot/dtbs/4.19.94-ti-r43/am335x-boneblack-uboot-univ.bak.dtb -
sudo cp ./src/arm/am335x-boneblack-uboot-univ.dtb /boot/dtbs/4.19.94-ti-r43/am335x-boneblack-uboot-univ -
dtdiff /boot/dtbs/4.19.94-ti-r43/am335x-boneblack-uboot-univ.bak.dtb /boot/dtbs/4.19.94-ti-r43/am335x-boneblack-uboot-univ.dtb -
verify no occurrences of
pwrin the decompiled tree:
-dtc -I dtb -O dts -o ./src.txt ./src/arm/am335x-boneblack-uboot-univ.dtb
-nano src.txt -
the
tps65217_pwr_butIRQ is still present -
check irq’s:
$ cat /proc/interrupts | grep 65217142: 0 INTC 7 Level tps65217-irq 144: 0 tps65217 0 Edge vbus 145: 0 tps65217 2 Edge tps65217_pwr_but