Re: 2.6.10-mm2: it87 sensor driver stops CPU fan

Simone Piunno
2005-01-10T23:22:37Z

On Saturday 08 January 2005 10:34, Jean Delvare wrote:

> Could you please provide a dump of your it87 chip before loading the
> it87 driver? "isadump 0x295 0x296" should tell you. I would also be
> interested in a dump right after you load the driver if possible

Before loading it87:

0 1 2 3 4 5 6 7 8 9 a b c d e f
00: 11 00 00 00 37 ff 00 37 ff 07 00 5b 00 2a ff ff
10: ff ff ff 30 00 00 00 00 00 00 00 00 00 00 00 00
20: 5c 9f ce b0 bf b2 83 aa 00 19 29 7f 00 00 00 00
30: ff 00 ff 00 ff 00 ff 00 ff 00 ff 00 ff 00 ff 00
40: 7f 7f 7f 7f 7f 7f 00 00 2d 00 00 00 00 00 00 00
50: ff 38 7f 7f 7f 00 00 00 90 4f 06 00 50 00 00 00
60: 7f 7f 7f 7f 7f 00 00 00 7f 7f 7f 7f 7f 00 00 00
70: 7f 7f 7f 7f 7f 00 00 00 00 00 00 00 00 00 00 00
80: 11 00 00 00 37 ff 00 37 ff 07 00 5b 00 2a ff ff
90: ff ff ff 30 00 00 00 00 00 00 00 00 00 00 00 00
a0: 5c 9f ce b0 bf b2 83 aa 00 19 29 7f 00 00 00 00
b0: ff 00 ff 00 ff 00 ff 00 ff 00 ff 00 ff 00 ff 00
c0: 7f 7f 7f 7f 7f 7f 00 00 2d 00 00 00 00 00 00 00
d0: ff 38 7f 7f 7f 00 00 00 90 4f 06 00 50 00 00 00
e0: 7f 7f 7f 7f 7f 00 00 00 7f 7f 7f 7f 7f 00 00 00
f0: 7f 7f 7f 7f 7f 00 00 00 00 00 00 00 00 00 00 00

After loading it87:

0 1 2 3 4 5 6 7 8 9 a b c d e f
00: 11 03 60 00 37 ff 00 37 ff 07 00 5b 00 ff ff ff
10: fe fe fe 31 07 7f 00 00 00 00 00 00 00 00 00 00
20: 5c 9f ce b2 be a9 69 ac 00 19 26 7f 00 00 00 00
30: 62 4d a4 94 d9 c4 c3 b1 c5 b2 82 78 80 79 cd a7
40: 28 0f 2d 0f 2d 0f 00 00 2d 00 00 00 00 00 00 00
50: ff 38 7f 7f 7f 00 00 00 90 4f 06 00 50 00 00 00
60: 7f 7f 7f 7f 7f 00 00 00 7f 7f 7f 7f 7f 00 00 00
70: 7f 7f 7f 7f 7f 00 00 00 00 00 00 00 00 00 00 00
80: 11 00 00 00 37 ff 00 37 ff 07 00 5b 00 ff ff ff
90: fe fe fe 31 07 7f 00 00 00 00 00 00 00 00 00 00
a0: 5c 9f ce b2 be a9 69 ac 00 19 26 7f 00 00 00 00
b0: 62 4d a4 94 d9 c4 c3 b1 c5 b2 82 78 80 79 cd a7
c0: 28 0f 2d 0f 2d 0f 00 00 2d 00 00 00 00 00 00 00
d0: ff 38 7f 7f 7f 00 00 00 90 4f 06 00 50 00 00 00
e0: 7f 7f 7f 7f 7f 00 00 00 7f 7f 7f 7f 7f 00 00 00
f0: 7f 7f 7f 7f 7f 00 00 00 00 00 00 00 00 00 00 00

> (but don't burn your CPU for me).

Oh, don't worry.
I've already coded a small fan controller daemon working around the problem
and driving the fan to run at the minimum speed sufficient to keep the CPU
cool enough. Anyone interested can look here:
http://svn.ferrara.linux.it/view/just4fan
or check it out from the subversion repository:
svn checkout http://svn.ferrara.linux.it/just4fan
In fact, now I run the system with it87 always loaded... it's soooo quiet!
Now that I'm used to this silence I can't live without it: I can't stand the
fan screaming anymore! I think for I won't move away from -mm until this
single feature makes it into vanilla :)

> Do you know what kind of it87 chip you do have? There are three of them,
> IT8705F, IT8712F and a SIS950 clone (mostly similar to the IT8705F).

I'm sorry I don't know. How I could check?

Thanks again
/Simone

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