Date: Wed, 23 Apr 2008 12:46:37 -0700 From: Nate Lawson <nate@root.org> To: Andriy Gapon <avg@icyb.net.ua> Cc: freebsd-acpi@freebsd.org Subject: Re: initial value of tz_active Message-ID: <480F921D.3050505@root.org> In-Reply-To: <480F8E2E.8000502@icyb.net.ua> References: <480F8E2E.8000502@icyb.net.ua>
next in thread | previous in thread | raw e-mail | index | archive | help
Andriy Gapon wrote: > It seems that tz_active (in acpi_thermal) is initialized to NONE/-1. > I don't have a patch, but I have an idea - acpi_thermal should query > current power state of fans and set tz_active based on that. > For example, some systems start up with all fans turned on (at full > speed) for safety reasons, acpi_thermal sees that temperature is low > enough, it thinks/assumes that no fan is active, so it doesn't change AC > level, so in reality AC0 is always in effect. Good point. I think there should be a "first_time" static that is set on boot. Once acpi_thermal decides to turn some fans on or off, first_time is set. Until it has been set, all fan control is actually performed, regardless of tz_active. After it is set, we can depend on tz_active as before. The reason we can't just read the fan status and initialize tz_active accordingly is that some ASL doesn't return the real value of the fans. It just returns a hard-coded value. On many systems, it does return the real value but if even one system is wrong, we can't trust any of them. -- Nate
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?480F921D.3050505>