Hi Anton, On Wed, 31 Jan 2007 11:18:04 +0100 (CET), Anton Ertl wrote: > This is somewhat of a reverse case of > > http://www.lm-sensors.org/ticket/1917 > > I have an ASUS K8V SE Deluxe board (and use the w83697hf driver for This driver doesn't exist, I'll assume you mean the w83627hf driver and your chip is a W83697HF. > it). I used to run a stock 2.6.13.2 kernel (with the perfctr patch) > and have now switched to a stock 2.6.19.2 (with the perfctr patch). I > have also switched from Gentoo to Debian, but I doubt that is the > issue. I used to have the Quiet Fan BIOS option enabled, but also > used the fancontrol script (fancontrol works much better, but not in > all OSs). > > The way this setup apparently worked was that, as soon as I or > fancontrol wrote something to /sys/bus/i2c/devices/.../pwm2 (which > controls the CPU fan), the Quiet Fan BIOS stopped controlling the fan, > so they worked together beautifully. Hmm, looking at ticket 1917, I > guess it was probably the loading of the module that disabled the > Quiet Fan feature. > > After the upgrade to 2.6.19.2, this no longer works that way. E.g., I > write to pwm2 and read it right back, like this: > > echo 100 >pwm2; cat pwm2 > > That usually displays the number (100) I wrote, but a short time > later, pwm2 contains some other number, apparently what the Quiet Fan > BIOS deems appropriate. > > I managed to work around this problem by disabling Quiet Fan in the > BIOS; then writing to pwm2 and fancontrol work as they have before. > > That workaround is good enough for me, but I still wonder if there is > a way to get the old behaviour back (so i can have the Quiet Fan > feature for other OSs). Any ideas? The old behavior isn't something we want to do again. Loading a driver should not reconfigure the hardware monitoring chip, doing so confuses the users a lot, especially when we offer no way to revert the change. We fixed the driver for that reason. > Looking at ticket 1917, a solution might be to let the user control > how aggressive the initialization should be. An automagic solution > would be to turn off Quiet Fan control when the first write to pwm2 > happens, but I don't know if this is feasible. You should be able to set the fan speed control to manual mode by writing 1 to pwm2_enable. Then values written to pwm2 should stick, as they used to. -- Jean Delvare
