Starting adb on boot process? For debugging purposes... - Android Q&A, Help & Troubleshooting

Hi guys, i successfully build from scratch a device and vendor tree for my rom, and compile CM13 with no problems.
The roms boots but i get a bootloop when it come into "starting apps". My idea is get adb working on boot proccess.
I was googling but i couldn't get working....
This is my init.qcom.rc: https://drive.google.com/open?id=0ByjBTzGuQ9FIQldHTGxBWjdtczQ
And init.usb.rc generated by CM13: https://drive.google.com/open?id=0ByjBTzGuQ9FIc1ZVNnVpTVExOE0
Thanks

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Well guy i was digging around and testing ALOT with no luck. Still can't enable adb at boot.
I try adding this properties on default.prop:
Code:
ro.adb.secure=0
ro.secure=0
ro.debuggable=1
persist.sys.usb.config=mtp,adb
An this in build.prop:
Code:
ro.default_usb_mode=0
persist.service.adb.enable=1
persist.service.debuggable=1
persist.sys.usb.config=mtp,adb
My device is a Forge TV, and it have a single usb port and no sdcard slot, so the only way to get a log is via usb...
In the stock rom, by default, starts in host mode (storage) and you have to go into config to change it into "device mode" to get usb adb working....
Probably i need to manage how the usb port starts at boot, i thought that "ro.default_usb_mode=0" was the solution...but no
Any help will be appreciated!
PS. lsusb doesn't recognize any device....only in fastboot mode

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So i found out something interesting...in stock rom if i execute the command echo 0 > /proc/usb_device the device put itself in device mode and i can debug, putting that value to 1 reverts to storage.
I try to put that on init.d, or even on init.qcom.rc in the boot image with no luck....it's so frustating...

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Ususally adbd should already be running this late during the boot.
Can you at least get an usb connection during boot? (check lsusb)
If you want to get at least a dmesg output during boot you could try the following:
set this in the build.prop
Code:
debug.sf.nobootanimation=1
set the following in your kernel defconfig
Code:
CONFIG_VGA_CONSOLE=y
CONFIG_FRAMEBUFFER_CONSOLE=y
CONFIG_FRAMEBUFFER_CONSOLE_DETECT_PRIMARY=y
CONFIG_FONT_8x8=y
CONFIG_FONT_8x16=y
(not all of them are needed but I forgot which ones are and which ones are not)
add this to the kernel command line
Code:
console=tty1 loglevel=7
This should at least show some output on the phone screen itself.
To run something in the console, you could try to connect an usb keyboard or use something like a scriptable virtual keyboard.
You might need to set loglevel to 1 or 0 if you don't want it to spam your console while working on it.

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ruleh said:
Ususally adbd should already be running this late during the boot.
Can you at least get an usb connection during boot? (check lsusb)
If you want to get at least a dmesg output during boot you could try the following:
set this in the build.prop
Code:
debug.sf.nobootanimation=1
set the following in your kernel defconfig
Code:
CONFIG_VGA_CONSOLE=y
CONFIG_FRAMEBUFFER_CONSOLE=y
CONFIG_FRAMEBUFFER_CONSOLE_DETECT_PRIMARY=y
CONFIG_FONT_8x8=y
CONFIG_FONT_8x16=y
(not all of them are needed but I forgot which ones are and which ones are not)
add this to the kernel command line
Code:
console=tty1 loglevel=7
This should at least show some output on the phone screen itself.
To run something in the console, you could try to connect an usb keyboard or use something like a scriptable virtual keyboard.
You might need to set loglevel to 1 or 0 if you don't want it to spam your console while working on it.
Click to expand...
Click to collapse
Hi, thanks alot for your answer! My device is a Razer Forge TV wich is an Android TV device. It's equiped with a single full usb 3.0 port and no sdcard slot. The port works in 2 ways, by default in host mode and device mode (the mode i need to get some debug output). In the stock rom executing "echo 0 > /proc/usb_device" enable this mode and remains on reboot. But doesn't seems to work on CM (i put the command on an init.d script). lsusb reports nothing (equal in stock rom when the port is in host mode).
I test the soluton you provided, but instead of bootanimation i get a black screen then optimizing apps, starting apps and reboot (wich is my main problem)....there's no output on screen...i'm stuck on this like 10 days or more...is so annoying...thanks again

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achaw said:
Hi, thanks alot for your answer! My device is a Razer Forge TV wich is an Android TV device. It's equiped with a single full usb 3.0 port and no sdcard slot. The port works in 2 ways, by default in host mode and device mode (the mode i need to get some debug output). In the stock rom executing "echo 0 > /proc/usb_device" enable this mode and remains on reboot. But doesn't seems to work on CM (i put the command on an init.d script). lsusb reports nothing (equal in stock rom when the port is in host mode).
I test the soluton you provided, but instead of bootanimation i get a black screen then optimizing apps, starting apps and reboot (wich is my main problem)....there's no output on screen...i'm stuck on this like 10 days or more...is so annoying...thanks again
Click to expand...
Click to collapse
You could try to insert a usb stick, mount it, and then write dmesg and/or adb output to it using init.rc.
Alternatively you could try to enable adb over tcp and connect that way to it.
Alos try to chose a different tty in the kernel command line.
(btw are the following three lines present in your kernel defconfig?)
Code:
CONFIG_VT_CONSOLE=y
CONFIG_TTY=y
CONFIG_VT=y

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ruleh said:
You could try to insert a usb stick, mount it, and then write dmesg and/or adb output to it using init.rc.
Alternatively you could try to enable adb over tcp and connect that way to it.
Alos try to chose a different tty in the kernel command line.
(btw are the following three lines present in your kernel defconfig?)
Code:
CONFIG_VT_CONSOLE=y
CONFIG_TTY=y
CONFIG_VT=y
Click to expand...
Click to collapse
I can't mount usb or enable adb over tcp becasuse the system reboot itself at starting apps...
Right now i'm testing with your new config, switching ttys because i'm still getting black screen instead some output...

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Well after some days i remember that the Forge iss equipped with a ethernet port...i feel so stupid lol...
So i was able to debug via adb over tcp.... @ruleh thanks alot for your time!

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I think "starting apps" happens when zygote is started.
If it is really the case then it should be possible to mount an usb stick and write the logs to it before everything reboots.
According to the init files I have, init.${ro.hardware}.rc would be the place to do the mount+write.
Ideally /system is mounted and /system/bin is in the path to access tools like logcat and dmesg.
Otherwise you could include them in /sbin which is (in most cases) part of the ramdisk.
It would probably be something like this:
Code:
on early-boot
#mkdir /mnt/usb
mount /dev/(usb_stick) /mnt/usb
exec /system/bin/dmesg > /mnt/usb/dmesg.log
exec /system/bin/logcat > /mnt/usb/logcat.log
(I have never used the init.rc files directly so I am not too sure.)
Also did you try "write /proc/usb_device 0" instead of "echo 0 > /proc/usb_device" in the init.rc files? (preferably before zygote starts...maybe init.usb.rc?)
Or you could try to remove the lines referencing zygote from the init.rc files and see if adbd starts then or not.
---------- Post added at 20:17 ---------- Previous post was at 20:16 ----------
achaw said:
Well after some days i remember that the Forge iss equipped with a ethernet port...i feel so stupid lol...
So i was able to debug via adb over tcp.... @ruleh thanks alot for your time!
Click to expand...
Click to collapse
I wish I read this a bit earlier...... oh well