[lm-sensors] w83627ehf-isa-0290 CPU fan rpm: wrong value

[lm-sensors] w83627ehf-isa-0290 CPU fan rpm: wrong value

[simone marchi]

Dear all,
I've a problem with that sensors about CPU fan RPM value reported.
My motherboard is a Asus A8V-E SE. 
I use SuSE 10.1. (2.6.16.21-0.13-default)

The sensors command report sometimes a correct value (~2200rpm) 
and other time a wrong value (~140rpm).
I've seen that the multiplier of the fan (fan2_div for me) 
switch between 4 and 64.
I tried to force manually the value to 4 by this command:
 
echo -n "4" > /sys/bus/i2c/devices/9191-0290/fan2_div
but I've got a "permission denied" (I ran the command as root)

If I list that file I got that result:
-r--r--r-- 1 root root 0 2006-09-08 16:43 
            /sys/bus/i2c/devices/9191-0290/fan2_div

So, I can't modify that value.
I've tried to chmod the fan2_div, but I can't chage the value yet.

I tried also with a more recent kernel (2.6.18-rc6) but
I got the same error
(with new kernel I can monitoring, in addition, the voltages)

Does anyone help me?

Thank you
Ciao simone

[lm-sensors] w83627ehf-isa-0290 CPU fan rpm: wrong value

[David Hubbard]

Hi Simone,

This is a hardware problem that has no easy solution. I believe you
have fans with three pins and three wires. (If the fan that is giving
you the wrong value is a four-wire fan, then this must be something
else.) Three-wire fans get an RPM count while the power is being
rapidly turned on and off. It can cause this kind of behavior.

Hope this helps,
David

On 9/8/06, simone marchi <simone.marchi at ilc.cnr.it> wrote:
> Dear all,
> I've a problem with that sensors about CPU fan RPM value reported.
> My motherboard is a Asus A8V-E SE.
> I use SuSE 10.1. (2.6.16.21-0.13-default)
>
> The sensors command report sometimes a correct value (~2200rpm)
> and other time a wrong value (~140rpm).
> I've seen that the multiplier of the fan (fan2_div for me)
> switch between 4 and 64.
> I tried to force manually the value to 4 by this command:
>
> echo -n "4" > /sys/bus/i2c/devices/9191-0290/fan2_div
> but I've got a "permission denied" (I ran the command as root)
>
> If I list that file I got that result:
> -r--r--r-- 1 root root 0 2006-09-08 16:43
>             /sys/bus/i2c/devices/9191-0290/fan2_div
>
> So, I can't modify that value.
> I've tried to chmod the fan2_div, but I can't chage the value yet.
>
> I tried also with a more recent kernel (2.6.18-rc6) but
> I got the same error
> (with new kernel I can monitoring, in addition, the voltages)
>
> Does anyone help me?
>
> Thank you
> Ciao simone
>
>
> _______________________________________________
> lm-sensors mailing list
> lm-sensors at lm-sensors.org
> http://lists.lm-sensors.org/mailman/listinfo/lm-sensors
>

[lm-sensors] w83627ehf-isa-0290 CPU fan rpm: wrong value

[simone marchi]

David Hubbard ha scritto:
> Hi Simone,
> 
> This is a hardware problem that has no easy solution. I believe you
> have fans with three pins and three wires. (If the fan that is giving
> you the wrong value is a four-wire fan, then this must be something
> else.) Three-wire fans get an RPM count while the power is being
> rapidly turned on and off. It can cause this kind of behavior.
> 
> Hope this helps,
> David
> 

Hi David,
thank you for your support!
My fan has three pens and three wires. I'm using the bundled fan with my
athlon64 3800+.
I've tried to do a simple (dangerous) hack of w83627ehf source code:
I've substitute all occurence of
w83627ehf_read_value(client, W83627EHF_REG_FANDIV1)
with the vale 4 (that works fine for me).
I know that can be very dangerous because I'm not kernel expert!
But it works fine!

So, I also tried to patch my kernel (2.6.18-rc6) with
gregkh-i2c-hwmon-w83627ehf-add-pwm-support.patch
to gain fancontrol also.
With this patch I can successfully controll my fan and get correct value
for rpm fan speed.

A simple report about fancontrol:
the pwmconfig configurator fails sometime and it says "no correlation".
But, if I try other times, it works fine and I can get fan control (with
pleasure :) )
The Q-fan2 Bios feature (by Asus) must be enabled or disabled ?

thank you
ciao simone

[lm-sensors] w83627ehf-isa-0290 CPU fan rpm: wrong value

[David Hubbard]

Hi Simone,

You should be using at least the 2.6.17 kernel. The 2.6.18 kernel will
be ready soon. The gregkh-i2c-hwmon-w83627ehf-add-pwm-support.patch is
in these kernels. What kernel are you using?

Glad you are making some progress.

David

[lm-sensors] w83627ehf-isa-0290 CPU fan rpm: wrong value

[simone marchi]

David Hubbard ha scritto:
> Hi Simone,
> 
> You should be using at least the 2.6.17 kernel. The 2.6.18 kernel will
> be ready soon. The gregkh-i2c-hwmon-w83627ehf-add-pwm-support.patch is
> in these kernels. What kernel are you using?
> 
> Glad you are making some progress.
> 
> David

Hi David,
I'm using 2.6.18-rc6 (official, without any other patch) and the 
gregkh's patch isn't in that release (I believe...).
It'll be included in the final kernel release of 2.6.18 version?

Thank you very much.

ciao simone

[lm-sensors] w83627ehf-isa-0290 CPU fan rpm: wrong value

[David Hubbard]

Hi Simone,

> Hi David,
> I'm using 2.6.18-rc6 (official, without any other patch) and the
> gregkh's patch isn't in that release (I believe...).
> It'll be included in the final kernel release of 2.6.18 version?

It has been accepted for inclusion in a kernel. I don't actually know
how it works from there. I assume 2.6.18, but maybe 2.6.19... ?

David