Power Management Overview


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This index page is intended to be for aggregation, summarizing and linking to all of the many existing pages discussing different aspects of power management on the XO laptop family.

Information currently on the wiki varies a lot, in both accuracy and currency. Some pages describe early designs, only some of which were ever implemented, some describe early progress during XO-1 hardware development. Other pages that were correct for initial software releases on the XO-1 don't correctly describe the XO-1.5 hardware, or later software releases.

New pages are needed describing both existing implementation of power management on XO-1 and XO-1.5 in the 10.1.X releases, and discussions of proposed scenarios and solutions for XO-1.75.

System description pages

Power management This very long page contains a fairly detailed description of the XO-1 hardware, paying special attention to the power requirements and implications of each piece. Some of it was overly optimistic, some parts (describing unchanged hardware modules) still pertain to the XO-1.5. Non-power discussions include security, the boot sequence, the device tree, LED status indicators, language support.

OHM power management describes how to interact with and control "ohmd", the power management daemon used on initial (including G1G1) releases of the XO-1. Also describes the actions ohmd takes in response to various user actions (lid close, keypress, batter insertion, etc).

XO 1.5 ACPI hardware support contains comparisons of the exposed interfaces available for power management on the XO-1 and XO-1.5 laptops.

powerd is the power management daemon used on XO-1.5, and on recent (10.1.X) releases for XO-1.

User and deployment support pages

XO Power Draw Describes tools that can be used to measure system power use, as well as the many modes of operation that can change the laptop's power requirements. Some sample measurements are also included

Support FAQ/Power Generation, Power Management, Battery Issues gives answers to common questions asked about power on the initial software releases for the XO-1. FAQ entries range from expected battery life to specific software bugs.

Battery_and_Power describes the battery charging system, and various alternate (and/or non-traditional) charging mechanisms. Lots of user contributions. Includes details specs on the laptop's hard-to-find charging jack.

Historical pages, largely outdated

Power Management Software dates from 2007, and consists mainly of a few early thoughts and questions about how power management might work. Not much of interest here in 2011.

Power Management Interface also from early 2007, this page consists almost entirely of retracted design thoughts.

Power Management Tips Very briefly describes how lid open/close events can be monitored, and how the DCON can be enabled/disabled.

Power Management Scenarios briefly describes (from a 2007/2008 perspective) the XO-1's intended suspend and idle states, as managed by ohmd.

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