Bug 14429

Reassigned to Nicolas.

I noticed the same thing.. with the iMac9,1 and the MacBookPro2,2

I sent a patch to kernel.org, and have not received any info on the status.
of these patches, here's the thread:
http://lkml.org/lkml/2010/4/5/152
(give them a try and see)

right now both machines report the temperature info without the input/output
error with 
watch cat /sys/devices/platform/applesmc.768/temp*_input

Created attachment 25909 [details]
[PATCH]fix-input-output-error-with-iMac9-1-and-MacBookPro2,2

This patch adds temperature sensors for the iMac9,1 and
the MacBookPro2,2 resulting in fixing the input/output error
when issuing the command:
watch cat /sys/devices/platform/applesmc.768/temp*_input
on both of the machines.

On my system (iMac 8,1):

applesmc: wait status failed: 5 != 1
applesmc: wait status failed: 5 != 1
applesmc: wait status failed: 5 != 1
applesmc: wait status failed: 5 != 1
applesmc: wait status failed: 5 != 1
applesmc: wait status failed: 5 != 1
applesmc: wait status failed: 4 != 5
applesmc: wait status failed: 5 != 1
applesmc: wait status failed: 4 != 0
applesmc: wait status failed: 4 != 0
applesmc: wait status failed: 5 != 1
applesmc: wait status failed: 5 != 1
applesmc: wait status failed: 4 != 0
applesmc: wait status failed: 4 != 0
applesmc: wait status failed: 5 != 1

and gnome system monitor sometimes report error.

root@imac:~# uname -a
Linux imac 2.6.32-24-generic-pae #42-Ubuntu SMP Fri Aug 20 15:37:22 UTC 2010 i686 GNU/Linux

theres an entry for the imac8,1 in applesmc.c, wondering if 2.6.32 has that entry in there?,if not then maybe upgrade to the current HEAD to see if this corrects the issue.. also make sure that the temp sensors are correct i.e. my macbookpro was wrong, after making the fix, I dont get input/output errors when using cat for the temp sensors. here is how to get them(example):
 http://mactel-linux.sourceforge.net/wiki/AppleSMC

mmarkk@imac:~$ sensors
applesmc-isa-0300
Adapter: ISA adapter
ODD :        699 RPM  (min =  700 RPM)
HDD :       1200 RPM  (min = 1200 RPM)
CPU :       1199 RPM  (min = 1200 RPM)
temp1:       +24.5°C                                    
temp2:       +43.0°C                                    
temp3:       +43.2°C                                    
temp4:       +46.0°C                                    
temp5:       +61.5°C                                    
temp6:       +53.0°C                                    
temp7:       +53.0°C                                    
temp8:       +49.5°C                                    
temp9:       +50.5°C                                    
temp10:      +43.5°C                                    
temp11:      +50.5°C                                    
temp12:      +47.2°C                                    
temp13:      +72.2°C                                    

coretemp-isa-0000
Adapter: ISA adapter
Core 0:      +50.0°C  (high = +105.0°C, crit = +105.0°C)  

coretemp-isa-0001
Adapter: ISA adapter
Core 1:      +48.0°C  (high = +105.0°C, crit = +105.0°C)  

mmarkk@imac:~$ 

It appear that all sensors are OK. How I can help diagnose problem? (I'll try ubuntu 10.10 soon)

Created attachment 30302 [details]
imac8,1

imac8,1

good the temp sensors are correct... as for the problem does this still happen with the current git HEAD?

as for the code Im seeing:
/*
229  * __wait_status - Wait up to 32ms for the status port to get a certain value
230  * (masked with 0x0f), returning zero if the value is obtained.  Callers must
231  * hold applesmc_lock.
232  */
233 static int __wait_status(u8 val)
234 {

in applecms.c

Fixed by:

http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=e1741712e85cec8004c7eeeea81186618f78eff1

tough to say if this was the real fix for this..(Im not seeing anything like that but will keep an eye out for anything)