The tp_smapi kernel module exposes some features of the ThinkPad hardware/firmware via a sysfs interface. Currently, the main implemented functionality is control of battery charging and extended battery status. The underlfying hardware interfaces are SMAPI and direct access to the embedded controller.
For older ThinkPad models, see also tpctl.
- Battery charge/discharge control
- Battery status information
- PCI bus power saving control
Project Homepage / Availability
- Project page: http://tpctl.sourceforge.net/
- You need to download only the tp_smapi package. Versions containing -test are experimental, others are stable.
Installation from source
You will need the kernel headers and makefiles corresponding to your current kernel version. On Fedora, this means
# yum install kernel-devel-$(uname -r) .
For testing, you can simply compile and load the driver within the current working directory:
# tar xzvf tp_smapi-0.30.tgz
# cd tp_smapi-0.30
# make load
To compile and install into the kernel's module path:
# make install
If you use the HDAPS driver, add HDAPS=1 to also patch the hdaps for compatibility with tp_smapi (this requires a kernel source tree matching the current kernel):
# make load HDAPS=1
or, to compile and install into the kernel's module path:
# make install HDAPS=1
To prepare a stand-alone patch against the current kernel tree (including a patch against hdaps and new Kconfig entries):
# make patch
To delete all autogenerated files:
# make clean
The original kernel tree is never modified by any these commands.
The /lib/modules directory is modified only by
# make install.
Installation in Gentoo
If you use the HDAPS driver, do this first:
- Configure hdaps as module in your kernel
- Add the HDAPS use flag in /etc/make.conf
# rmmod hdaps
# emerge tp_smapi(or install tp_smapi with hdaps support manually, as above)
# echo "tp_smapi" >> /etc/modules.autoload.d/kernel-2.6
# echo "hdaps" >> /etc/modules.autoload.d/kernel-2.6
Then reboot, or run:
# modprobe tp_smapi
# modprobe hdaps
Installation on Debian/Ubuntu
deb http://www.oakcourt.dyndns.org/debian/ ./ deb-src http://www.oakcourt.dyndns.org/debian/ ./
This repository has kernel-patch packages for tp_smapi. This will not only integrate tp_smapi into your kernel build but will patch the hdaps driver for you. It is available for kernel 2.6.15 and later. Also available is an init script to automatically set SMAPI paramaters at boot--this is in package tpsmapi-utils. Please report any bugs to User:Ajbarr
Battery charge control features
To set the thresholds for starting and stopping battery charging (in percent of current full charge capacity):
# echo 40 > /sys/devices/platform/smapi/BAT0/start_charge_thresh
# echo 70 > /sys/devices/platform/smapi/BAT0/stop_charge_thresh
# cat /sys/devices/platform/smapi/BAT0/*_charge_thresh
To unconditionally inhibit charging for 17 minutes:
# echo 17 > /sys/devices/platform/smapi/BAT0/inhibit_charge_minutes
To cancel charge inhibiting:
# echo 0 > /sys/devices/platform/smapi/BAT0/inhibit_charge_minutes
To force battery discharging even if connected to AC, use one of these:
# echo 1 > /sys/devices/platform/smapi/BAT0/force_discharge
To cancel forced discharge:
# echo 0 > /sys/devices/platform/smapi/BAT0/force_discharge
Battery status features
To view extended battery status such as charging state, voltage, current, capacity, cycle count and model information:
# cat /sys/devices/platform/smapi/BAT0/installed # cat /sys/devices/platform/smapi/BAT0/state # idle/charging/discharging # cat /sys/devices/platform/smapi/BAT0/cycle_count # cat /sys/devices/platform/smapi/BAT0/current_now # instantaneous current # cat /sys/devices/platform/smapi/BAT0/current_avg # last minute average # cat /sys/devices/platform/smapi/BAT0/power_now # instantaneous power # cat /sys/devices/platform/smapi/BAT0/power_avg # last minute average # cat /sys/devices/platform/smapi/BAT0/last_full_capacity # cat /sys/devices/platform/smapi/BAT0/remaining_percent # cat /sys/devices/platform/smapi/BAT0/remaining_running_time # cat /sys/devices/platform/smapi/BAT0/remaining_charging_time # cat /sys/devices/platform/smapi/BAT0/remaining_capacity # cat /sys/devices/platform/smapi/BAT0/design_capacity # cat /sys/devices/platform/smapi/BAT0/voltage # cat /sys/devices/platform/smapi/BAT0/design_voltage # cat /sys/devices/platform/smapi/BAT0/manufacturer # cat /sys/devices/platform/smapi/BAT0/model # cat /sys/devices/platform/smapi/BAT0/barcoding # cat /sys/devices/platform/smapi/BAT0/chemistry # cat /sys/devices/platform/smapi/BAT0/serial # cat /sys/devices/platform/smapi/BAT0/manufacture_date # cat /sys/devices/platform/smapi/BAT0/first_use_date # cat /sys/devices/platform/smapi/BAT0/temperature # in milli-Celsius # cat /sys/devices/platform/smapi/ac_connected
The raw status data is also available, including some fields not listed above (in case you can figure them out):
# cat /sys/devices/platform/smapi/BAT0/dump
In all of the above, replace BAT0 with BAT1 to address the 2nd battery.
On ACPI-enabled systems, most of above information is also available through the files under /proc/acpi/battery. However, the ACPI interface does not include the instantaneous power and cycle count readouts, and does not work well when hotswapping UltraBay batteries.
This controls the "PCI bus power saving" option in the BIOS, and takes effect at the next boot. On a ThinkPad T43 turning this off increases idle power consumption by about 350mW. Out-of-the-box default is 1.
# cat /sys/devices/platform/smapi/enable_pci_power_saving_on_boot # echo 1 > /sys/devices/platform/smapi/enable_pci_power_saving_on_boot # on # echo 0 > /sys/devices/platform/smapi/enable_pci_power_saving_on_boot # off
There is also sysfs attribute for making direct SMAPI requests to the SM BIOS firmware. Don't touch it unless you really know what you're doing. Example:
# echo '211a 100 0 0 > /sys/devices/platform/smapi/smapi_request; cat /sys/devices/platform/smapi/smapi_request 211a 34b b2 0 0 0 'OK'
The 4b" in the 2nd value, converted to decimal is 75: the current charge stop threshold.
Conflict with hdaps
The extended battery status function conflicts with the hdaps kernel module (they use the same IO ports). The tp_smapi package includes a patch against hdaps to make it compatible with tp_smapi, and also to fix many problems in the original driver.
To build the patched version, simply append the HDAPS=1 parameter to the make command, for example:
# make load HDAPS=1 (see Installation above).
If you don't do that, you will not be able tp load tp_smapi (and its support module tp_base) when hdaps is loaded, and vice versa. You can use rmmod to switch between these modules.
Note that some of the battery status is also visible through ACPI (/proc/acpi/battery/*), independently of tp_smapi.
|force_discharge||battery status files|| cd_speed
|R31||no||no||no||no||no||no||No SMAPI BIOS|
|T20||no||no||no||no||no||unknown||Has SMAPI BIOS but no function is supported. EC LPC3 protocol fails.|
|T22||no||no||no||no||no||unknown||Has SMAPI BIOS but no function is supported. EC LPC3 protocol fails.|
|X20 2662-31G||no||no||no||no||no||unknown||tp_smapi 0.20|
|X40||yes||yes||yes||unknown||yes||unknown||BIOS v2.03, EC v1.60|
Please update the above and report your experience on the discussion page. If the module loads but gives a "not supported" or "not implementeded" when you try to use some specific file in /sys/devices/platform/smapi/, please report the dmesg output and whether the corresponding functionality is available under Windows - maybe your ThinkPad just can't do that.
While at it, you may also want to add your laptop to the list of DMI IDs.
Tools using this driver
The driver's interface can be accessed directly through the files under /sys/devices/platform/smapi, or via the following tools: