[libhid-discuss] linux usbhid module claiming my device

[Gabriel Rossetti]

Charles Lepple wrote:
> On Sep 9, 2009, at 10:35 AM, Gabriel Rossetti wrote:
>
>> Hello,
>>
>> I have a problem where on linux the usbhid module claims my custom 
>> device. I used the hid_force_open() function and it is able to 
>> release the device and claim it but when I try to use 
>> hid_interrupt_read() it says that the device is busy :
>>
>> NOTICE: hid_force_open(): successfully opened USB device 001/035[0].
>> TRACE: hid_interrupt_read(): retrieving interrupt report from device 
>> 001/035[0] ...
>> WARNING: hid_interrupt_read(): failed to get interrupt read from 
>> device 001/035[0]: could not claim interface 0: Device or resource busy
>
> Is there any indication that the usbhid module is still claiming the 
> device after you successfully use hid_force_open()? If so, then 
> usb_detach_kernel_driver_np() is not doing its job, and it might be a 
> libusb question.
>

I think it's doing it's job correctly, but the hid driver either 
reclaims it or it tries to claim it after libhid has claimed it already.

>> Does anyone know how to deal with this (hopefully programically)? I 
>> use version 0.2.15+20060325-2.1 (ubuntu 8.04), installed using aptitude.
>>
>> Thank you,
>> Gabriel
>>
>> PS
>> should I also post on libusb since libhid is built on top of it?
>
> Possibly. I wouldn't advise cross-posting directly - there probably 
> aren't too many people on the libusb list who know much about libhid.
>
> For reference, the source code to hid_force_open() is here:
> http://libhid.alioth.debian.org/doc/hid__opening_8c-source.html#l00241