Re: [libusb] Accessing managed devices with OS X

[Xiaofan C. <xia...@gm...>]

On Thu, Oct 31, 2013 at 4:30 PM, Xiaofan Chen <xia...@gm...> wrote:
> On Tue, Oct 29, 2013 at 10:27 PM, Emmanuel Blot <ebl...@gm...> wrote:
>> Starting with 10.9 (Mavericks), OS X ships with an FTDI USB native driver.
>>
>> I'm using this kind of devices from libusbx, however because of this
>> new native driver, libusbx is unable to take control of the device,
>> the following error is returned:
>>
>>  Access denied (insufficient permissions)
>>
>> A workaround is available: unloading the native driver with the
>> following command:
>>
>>   sudo kextunload -bundle com.apple.driver.AppleUSBFTDI

Yes I can see this happen for my newly upgraded OS X 10.9 installation
(from 10.7 Lion).

mymacmini:examples xiaofanc$ ./find_all_pp -v 0x0403 -p 0x6001
Found devices ( VID: 0x403, PID: 0x6001 )
------------------------------------------------
FTDI (0x7fe480502c00): ftdi, usb serial converter, ftDEH51S (Open FAILED)

mymacmini:examples xiaofanc$ sudo kextunload -bundle
com.apple.driver.AppleUSBFTDI
Password:

mymacmini:examples xiaofanc$ ./find_all_pp -v 0x0403 -p 0x6001
Found devices ( VID: 0x403, PID: 0x6001 )
------------------------------------------------
FTDI (0x7fd129c0b4d0): ftdi, usb serial converter, ftDEH51S (Open OK)

>> Under Linux, detach_kernel_driver() can be used for this purpose,
>> however AFAIU it is not supported on Darwin. Is there any other way to
>> access the device without unloading the driver?
>>
>> Sorry if it's a duplicate, I tried to browse libusbx KB, but the Trac
>> instance is in trouble (see Python traceback below).
>>
>
> I am not so sure if a codeless kext can prevent the driver from loading
> or not. Probably worth a try.

Will try this later. But this may not be a very good solution (even if it
works) since it is more troublesome than your workaround.

-- 
Xiaofan