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I have a thinkpad edge 13, with the package tp-smapi-dkms installed. As described in these instructions, I have also run sudo modprobe tp_smapi, and added tp_smapi to /etc/modules

Before upgrade to 11.10, I used to be able to change thresholds for stopping battery charging. I would open the file /sys/devices/platform/smapi/BAT0/stop_charge_thresh as administrator and change the value from 100 to 85. Now, I am no longer able to directly edit that file. I also tried sudo echo 85 > /sys/devices/platform/smapi/BAT0/stop_charge_thresh but get Permission denied.

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up vote 3 down vote accepted

You should do as showing below:

sudo sh -c 'echo XX > /sys/devices/platform/smapi/BAT0/stop_charge_thresh'

But I also suffer from trouble in ThinkPad X201s + Ubuntu 11.10.

  1. Battery keeps discharging while I connect my ThinkPad X201s to AC adapter.
  2. Before update Ubuntu, charge_thresh values are shared with Windows configuration. But after upgrade, the value of threshold are initialized to 95 & 100 while it is configured to 75 & 95 in Windows.
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