"Timer expired" error when reading battery sys entries

[kriss]

Some of the entries in the battery sysfs directory are returning errors mesages when read.

Linux om-gta02 2.6.24 #1 PREEMPT Wed Jul 23 06:34:19 CEST 2008 armv4tl unknown

Example:

root@om-gta02:~# for i in /sys/devices/platform/bq27000-battery.0/power_supply/bat/*; do echo "==========================="; echo $i; cat $i; done
===========================
/sys/devices/platform/bq27000-battery.0/power_supply/bat/capacity
cat: read error: Timer expired
===========================
/sys/devices/platform/bq27000-battery.0/power_supply/bat/charge_full
cat: read error: Timer expired
===========================
/sys/devices/platform/bq27000-battery.0/power_supply/bat/current_now
cat: read error: Timer expired
===========================
/sys/devices/platform/bq27000-battery.0/power_supply/bat/device
cat: read error: Is a directory
===========================
/sys/devices/platform/bq27000-battery.0/power_supply/bat/online
1
===========================
/sys/devices/platform/bq27000-battery.0/power_supply/bat/power
cat: read error: Is a directory
===========================
/sys/devices/platform/bq27000-battery.0/power_supply/bat/present
0
===========================
/sys/devices/platform/bq27000-battery.0/power_supply/bat/status
Not charging
===========================
/sys/devices/platform/bq27000-battery.0/power_supply/bat/subsystem
cat: read error: Is a directory
===========================
/sys/devices/platform/bq27000-battery.0/power_supply/bat/technology
Li-ion
===========================
/sys/devices/platform/bq27000-battery.0/power_supply/bat/temp
cat: read error: Timer expired
===========================
/sys/devices/platform/bq27000-battery.0/power_supply/bat/time_to_empty_now
cat: read error: Timer expired
===========================
/sys/devices/platform/bq27000-battery.0/power_supply/bat/time_to_full_now
cat: read error: Timer expired
===========================
/sys/devices/platform/bq27000-battery.0/power_supply/bat/type
Battery
===========================
/sys/devices/platform/bq27000-battery.0/power_supply/bat/uevent
===========================
/sys/devices/platform/bq27000-battery.0/power_supply/bat/voltage_now
cat: read error: Timer expired
r

[andy]

What kind of battery is in there at this time? It says Model: GTA02 or something else?

[kriss]

It's a GTA01 Battery - rebooting with GTA02, be right back...

[kriss]

Oh it's working with that battery! - Is there a way to also support the GTA01 Battery ID?

[andy]

Nope, GTA02 battery has a nice monitoring chip we talk to in order to find out that stuff, GTA01 doesn't have anything like that. You can monitor voltage on the battery from another /sys node (although that monitoring is meant to be shaky at the moment), but that is quite hard to reliably relate to time until empty or time until full. So it's just something you can have with the shipping GTA02 battery.

Going to close as "invalid", since it is expected behaviour.

[kriss]

Thanks for the quick response!