Disable Power Button IRQ from TPS65217 on BBBW?

GoogleGroups
1

If I just tap the power button on the BBBW, 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
The image is from https://elinux.org/Beagleboard:BeagleBoneBlack_Debian#Debian_Buster_LXQt_Snapshot , as it works with the LCD out-of-the-box.

  • 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 the pwrbutton node
/*
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 the pwrbutton

  • pushd ~/BeagleBoard-DeviceTrees

  • nano -l ./src/arm/am335x-bone-common.dtsi

  • the line to edit is ~365

  • change status from okay to disabled:

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 pwrbutton section commented out in tps65217.dtsi
  • pwrbutton set to disabled in am335x-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 {
  • check IRQ’s:
    $ cat /proc/interrupts | grep 65217
142: 0 INTC 7 Level tps65217-irq
144: 0 tps65217 0 Edge vbus
145: 0 tps65217 2 Edge tps65217_pwr_but
2

Added another test, below (without success), and also posted this to https://forum.digikey.com/t/disable-power-button-irq-from-tps65217-on-bbbw/9803

  • 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.dtb instead of am335x-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 pwr in the decompiled tree:

  • dtc -I dtb -O dts -o ./src.txt ./src/arm/am335x-boneblack-uboot-univ.dtb

  • nano src.txt

  • the tps65217_pwr_but IRQ is still present

  • check irq’s:
    $ cat /proc/interrupts | grep 65217

142: 0 INTC 7 Level tps65217-irq
144: 0 tps65217 0 Edge vbus
145: 0 tps65217 2 Edge tps65217_pwr_but
3

You can disable teh cape universal redirect with disabling this line
in /boot/uEnv.txt

enable_uboot_overlays=1

You can also just not build with the tps65218-pwrbutton driver:

https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/drivers/input/misc/tps65218-pwrbutton.c

Regards,

4

Thanks, Robert. Unfortunately, commenting out either line in uEnv.txt,
#enable_uboot_overlays=1 or

#enable_uboot_cape_universal=1

the TPS65217 IRQ still exists:

$ cat /proc/interrupts | grep 65217
60: 0 INTC 7 Level tps65217-irq
62: 0 tps65217 0 Edge vbus
63: 0 tps65217 2 Edge tps65217_pwr_but

And, PWM no longer works using the Python scripts, even after restoring the original dtb files.

Is this the appropriate information source for building the kernel?

Joe

5

Thanks, Robert. Unfortunately, commenting out either line in uEnv.txt,
`#enable_uboot_overlays=1` or
`#enable_uboot_cape_universal=1`
the TPS65217 IRQ still exists:
$ cat /proc/interrupts | grep 65217
60: 0 INTC 7 Level tps65217-irq
62: 0 tps65217 0 Edge vbus
63: 0 tps65217 2 Edge tps65217_pwr_but
And, PWM no longer works using the Python scripts, even after restoring the original dtb files.

Correct, you'd have to enable pwm..

User cross posted here:

With the dtb hack to make tps65217_pwr_but disappear..

Is this the appropriate information source for building the kernel?
- Debian: Getting Started with the BeagleBone Black - Linux Guides - Electronic Component and Engineering Solution Forum - TechForum │ Digi-Key
We're currently using this lxqt image for the BBBW:
- Beagleboard:BeagleBoneBlack Debian - eLinux.org

Correct

Regards,