The OMAP3 hardware architecture contains a wealth of power management features.· Unfortunately, mainline Linux support for these features has been quite limited until recently.
Gumstix suggests that customers review this overview of OMAP3 power management with 2.6.39-pm - by Steve Sakoman, which takes a brief look at the state of power management as of June 2011
Gumstix has implemented the TPS65950 integrated power management IC from Texas Instruments on each Overo COM. The·TPS65950 integrated power management IC has 3 DC/DC's, 11 LDO's, audio codec, USB HS transceiver & charger.
The power management features are still in an experimental branch of Linux-OMAP, so Gumstix hasn't completed any testing. The current plan is to wait until these power management features are merged into the mainline Linux-OMAP to alleviate any concerns for their stability.
A Gumstix Overo COM draws·250 mA @ 4v (with Wifi & Bluetooth switched off)
For the TPS65950 interrupt lines on the Overo COM,
- Gumstix Overo COM FAB revisions >= 2516, INT1 is connected to GPIO_0_4030 IRD on the OMAP.
- Gumstix Overo COM FAB revisions <= 2410, INT1 is connected toGPIO112_4030 IRQ on the OMAP.