Difference between revisions of "ADC overo 2.6.39+"
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curr10_input in11_input in3_input in7_input power | curr10_input in11_input in3_input in7_input power | ||
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driver in12_input in4_input in8_input subsystem | driver in12_input in4_input in8_input subsystem | ||
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hwmon in15_input in5_input in9_input temp1_input | hwmon in15_input in5_input in9_input temp1_input | ||
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in0_input in2_input in6_input modalias uevent | in0_input in2_input in6_input modalias uevent | ||
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root@omap3-multi:~# cat /sys/class/hwmon/hwmon1/device/temp1_input | root@omap3-multi:~# cat /sys/class/hwmon/hwmon1/device/temp1_input | ||
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56 | 56 | ||
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root@omap3-multi:~# cat /sys/class/hwmon/hwmon1/device/curr10_input | root@omap3-multi:~# cat /sys/class/hwmon/hwmon1/device/curr10_input | ||
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-750 | -750 | ||
Revision as of 00:48, 19 September 2011
Contents
Using the ADC's
From posts in the mailing list by Steve Sakoman and others
The madc driver is now upstream and in the process it moved to the hwmon subsystem. It is now even easier to access using the /sys/class interface:
root@omap3-multi:~# ls /sys/class/hwmon/hwmon1/device/
curr10_input in11_input in3_input in7_input power
driver in12_input in4_input in8_input subsystem
hwmon in15_input in5_input in9_input temp1_input
in0_input in2_input in6_input modalias uevent
root@omap3-multi:~# cat /sys/class/hwmon/hwmon1/device/temp1_input
56
root@omap3-multi:~# cat /sys/class/hwmon/hwmon1/device/curr10_input
-750
ADC's via a system call
a quick and very nasty way to access them is by a system call
C
system("cat /sys/class/hwmon/hwmon1/device/in7_input");
Python
os.system("cat /sys/class/hwmon/hwmon1/device/in7_input")
ADC's via sysfs in code
Python
import os
import sys
import subprocess
cmd1 = "cat /sys/class/hwmon/hwmon1/device/in7_input"
process = subprocess.Popen(cmd1, stdout=subprocess.PIPE , shell=True)
os.waitpid(process.pid, 0)[1]
udata = process.stdout.read().strip()
print udata
In console (in interactive mode)
python
Python 2.6.6 (r266:84292, Sep 1 2011, 13:08:10)
[GCC 4.3.3] on linux2
>>> import os
>>> import sys
>>> import subprocess
>>> cmd1 = "cat /sys/class/hwmon/hwmon1/device/in7_input"
>>> process = subprocess.Popen(cmd1, stdout=subprocess.PIPE , shell=True)
>>> os.waitpid(process.pid, 0)[1]
0
>>> udata = process.stdout.read().strip()
>>> print udata
1388
>>>
==
Building your own kernel
When building your own kernel Make sure your defconfig has CONFIG_TWL4030_MADC and CONFIG_SENSORS_TWL4030_MADC and make sure your rootfs has the module.
Link to kernel docs for Kernel driver twl4030-madc http://www.sakoman.com/cgi-bin/gitweb.cgi?p=linux-omap-2.6.git;a=blob;f=Documentation/hwmon/twl4030-madc-hwmon;h=ef7984317cecb29eca6ef23a30c21d920e66ef31;hb=refs/heads/omap-2.6.39-pm