Re: ez usb fx2 reset

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Alan,

> Other people know more about this than I do.  Isn't there a specific 
> request you send the device to cause the CPU to reset?
> 

Yes, the 0x01 bit in CPUC_REGS on the fx2 is toggled with control calls.

> 
> You're likely to run into trouble, because the reenumeration will cause
> the device's descriptors to change and that will cause the kernel to
> unbind the existing driver.  Thus the open call will end up associated
> with a defunct device instance.
> 
> Normally firmware is sent while probe() runs and the device's CPU is 
> reset right away.  The driver gets unbound and rebound, and the second 
> time through the probe() routine recognizes that the firmware has 
> already been installed.
> 

Good advice, I've done this in probe now, but still the behaviour is not what I
expect. Shouldn't the driver disconnect and then re-probe when the chip
renumerates? I don't have trouble keeping track of that two pass approach in 
probe.

I'm expecting the unbinding to happen automatically when I reset the CPU on the
USB chip. Is this an incorrect assumption? Should I manually bind/unbind?

I'm not even trying to download the firmware. Just trying to verify 
renumeration with the fx2 loader firmware.

regards,
John




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