FreeBSD ACPI on a Panasonic Y4

The Panasonic R/W/T/Y series is a set of ultralight notebooks, also available in a US model. I like the Y4-Y7 for their large screen, light weight, and long battery life.

There are a couple things needed to get suspend/resume working on these models in FreeBSD. To get the backlight on and video working again, we need to trigger the 0xc000 video BIOS reset. Set the following in /etc/sysctl.conf:


The built-in mouse is stuck once we resume. We need to reinitialize it by setting the following in /boot/loader.conf. This should really be done automatically since the reinitialization should work on most systems. But more testing will have to be done before that is enabled by default.


With these changes, I can suspend/resume to RAM successfully. For more info, check the handbook.

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