Charger mode on i.MX8MQ and Android 8.1

huanxin_jiang — Wed, 30 Jan 2019 04:30:48 GMT

We are developing on i.MX8MQ and Android 8.1 BSP. We have battery and need charger manager.

We have implemented the battery/charger drivers and the healthd daemon is working well. Android shows correct battery capacity and charging/discharging information. The question is if we power on the unit by plugging in the USB-C adapter it should boot into “charger” mode that shows a big battery icon on screen and plays charging animation. The method is setting “androidboot.mode=charger” in uboot but when I did this I didn’t see that the “charger” service is running. I can manually start the charger service by the following commands on the console:

$ su

# charger

It then starts the battery animation on the screen that is corresponding to the real battery level, and with the following logs (see attachments):

[ 19.315741] charger:

[ 19.318054] charger: *************** LAST KMSG ***************

[ 19.323904] charger:

[ 19.326273] charger: last_kmsg not found. Cold reset?

[ 19.331353] charger:

[ 19.333634] charger: ************* END LAST KMSG *************

[ 19.339481] charger:

[ 19.341763] charger: --------------- STARTING CHARGER MODE ---------------

[ 19.383070] charger: Could not open animation description at /res/values/charger/animation.txt

[ 19.391753] charger: Could not parse animation description. Using default animation.

So the key is to automatically start the “charger” service when “androidboot.mode=charger” is set. I tried to modify device/fsl/evk_8mq/init.rc and system/core/rootdir/init.rc, but it didn’t work. In system/core/init/init.cpp it triggers the “charger” event when boot mode is charger but it looks not working:

Can you help have a look on this?

Attached are a log that including the manual starting of the charger service, and a picture when the charger service is running.

It looks that we just need a simple setting in init.rc that starts the charger service if boot mode is charger. I did the following changes in init.rc, but it doesn’t work:

diff --git a/evk_8mq/init.rc b/evk_8mq/init.rc

index 3309b05..ebbd1a9 100644

--- a/evk_8mq/init.rc

+++ b/evk_8mq/init.rc

@@ -138,6 +138,17 @@ on early-boot

# Dectect DSF streams when scanning media

setprop ro.FSL_DSF_PARSER 1

+on charger

+ # Enable Power modes and set the CPU Freq Sampling rates

+ write /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor "powersave"

+ write /sys/devices/system/cpu/cpufreq/ondemand/up_threshold 90

+ write /sys/devices/system/cpu/cpufreq/ondemand/sampling_rate 50000

+ write /sys/devices/system/cpu/cpufreq/ondemand/io_is_busy 1

+ write /sys/devices/system/cpu/cpufreq/ondemand/sampling_down_factor 4

+ write /sys/devices/system/cpu/cpu1/online 0

+ write /sys/devices/system/cpu/cpu2/online 0

+ write /sys/devices/system/cpu/cpu3/online 0

service wpa_supplicant /vendor/bin/hw/wpa_supplicant \

-ip2p0 -Dnl80211 -c/data/misc/wifi/p2p_supplicant.conf -N \

-iwlan0 -Dnl80211 -c/data/misc/wifi/wpa_supplicant.conf \

@@ -223,6 +234,9 @@ service g3d /vendor/bin/g3d

group system

oneshot

+service charger /sbin/charger

+ class charger

on property:wc_transport.start_hci=true

start start_hci_filter

Thanks,

Huanxin Jiang

Netscout

Re: Charger mode on i.MX8MQ and Android 8.1

diegoadrian — Wed, 06 Feb 2019 22:42:44 GMT

Hello,

Just to be sure.

Are you trying to see the boot animation for the battery charging?

Anyway, Investigating I found that the BatteryMonitor.cpp file has something to do with the battery status of the device. Just let investigate a little more about this.

Best Regards,

Diego.

Re: Charger mode on i.MX8MQ and Android 8.1

huanxin_jiang — Wed, 20 Feb 2019 02:48:56 GMT

Thanks and we've resolved this issue. There was a SELINUX policy issue with the charger service.

Re: Charger mode on i.MX8MQ and Android 8.1

bettychen — Wed, 22 Feb 2023 03:11:13 GMT

Can u share how to fix it?
I have the same issue.
Thx.

i.MX ProcessorsのトピックRe: Charger mode on i.MX8MQ and Android 8.1

Charger mode on i.MX8MQ and Android 8.1

Re: Charger mode on i.MX8MQ and Android 8.1

Re: Charger mode on i.MX8MQ and Android 8.1

Re: Charger mode on i.MX8MQ and Android 8.1