Findind input event device path with libudev
Hi,
I found an example on how to use libudev to iterate over devices present in the system to find its precise path since the path can be different everytime we plug a device into the system.
http://www.signal11.us/oss/udev/
In this example, the type of device searched is hidraw, however I have already tried input, event, etc and none of this match criterias in the following function:
|*udev_enumerate_add_match_subsystem*(enumerate,*"hidraw"*);|
Only hidraw seems to work.
Can I use this technic to found the path a of input event device?
Thanks,
With my best regards,
Nuno
Hi,
After digging a little bit around this i found that my problem is with this function:
dev = udev_device *udev_device_get_parent_with_subsystem_devtype(dev,"usb","usb_device");
dev is always null. He can't find me the usb device for my input device. Maybe i'm not specifiying subsystem and dev type correctly.
If I make several calls to udev_device_get_parent I can get to the correct device.
Does anyone knows what should be the correct subsystem and dev type pair to find the parent usb device for an input device?
Thanks,
Nuno
Quoted 25 lines · Nuno Santos
Hi,
I found an example on how to use libudev to iterate over devices present in the system to find its precise path since the path can be different everytime we plug a device into the system.
http://www.signal11.us/oss/udev/
In this example, the type of device searched is hidraw, however I have already tried input, event, etc and none of this match criterias in the following function:
|*udev_enumerate_add_match_subsystem*(enumerate,*"hidraw"*);|
Only hidraw seems to work.
Can I use this technic to found the path a of input event device?
Thanks,
With my best regards,
Nuno
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Quoted 8 lines · On Wed, 16 Nov 2011 14:44:08 +0000 Nuno Santos <[email protected]> wrote:
Hi,
After digging a little bit around this i found that my problem is with this function:
dev =
udev_device*udev_device_get_parent_with_subsystem_devtype(dev,"usb","usb_device");
Quoted 9 lines
dev is always null. He can't find me the usb device for my input device. Maybe i'm not specifiying subsystem and dev type correctly.
If I make several calls to
udev_device_get_parentI can get to the correct device.Does anyone knows what should be the correct subsystem and dev type pair to find the parent usb device for an input device?
You can find out the most specific subsystem and devtype yourself using:
udevadm monitor
and then plugging the device in.
Regards,
Antonio
Signature · 8 lines
Antonio Ospite http://ao2.it PGP public key ID: 0x4553B001 A: Because it messes up the order in which people normally read text. See http://en.wikipedia.org/wiki/Posting_style Q: Why is top-posting such a bad thing?