[PATCH v4 1/4] cmd: bind: Add unbind command with driver filter

[Marek Vasut]

On 8/4/23 09:00, Miquel Raynal wrote:
> Hi Marek,
> 
> marex at denx.de wrote on Wed,  2 Aug 2023 14:46:54 +0200:
> 
>> Extend the driver core to perform lookup by both OF node and driver
>> bound to the node. Use this to look up specific device instances to
>> unbind from nodes in the unbind command. One example where this is
>> needed is USB peripheral controller, which may have multiple gadget
>> drivers bound to it. The unbind command has to select that specific
>> gadget driver instance to unbind from the controller, not unbind the
>> controller driver itself from the controller.
>>
>> USB ethernet gadget usage looks as follows with this change. Notice
>> the extra 'usb_ether' addition in the 'unbind' command at the end.
>> "
>> bind /soc/usb-otg at 49000000 usb_ether
>> setenv ethact usb_ether
>> setenv loadaddr 0xc2000000
>> setenv ipaddr 10.0.0.2
>> setenv serverip 10.0.0.1
>> setenv netmask 255.255.255.0
>> tftpboot 0xc2000000 10.0.0.1:test.file
>> unbind /soc/usb-otg at 49000000 usb_ether
> 
> This extra parameter does not seem to work on the BBBW. I cannot select
> the "usb_ether" driver like you do.
> 
> Good news though, I am now able to use fastboot, but it is not
> straightforward:
> 
> Here is my sequence right after the boot (reducing the dm tree output
> to the usb nodes for clarity):
> 
> => dm tree
>   misc          0  [ + ]   ti-musb-wrapper       |   |-- usb at 47400000
>   usb           0  [ + ]   ti-musb-peripheral    |   |   |-- usb at 47401000
>   ethernet      1  [ + ]   usb_ether             |   |   |   `-- usb_ether
>   bootdev       3  [   ]   eth_bootdev           |   |   |       `-- usb_ether.bootdev
>   usb           0  [   ]   ti-musb-host          |   |   `-- usb at 47401800
> => fastboot usb 0
> couldn't find an available UDC
> g_dnl_register: failed!, error: -19

That is expected and not a bug, since the beagle explicitly binds USB 
ethernet to MUSB gadget in board file, which is legacy deprecated way.

> exit not allowed from main input shell.
> => unbind /ocp/usb at 47400000/usb at 47401000 usb_ether

Does

=> unbind ethernet 0

work ?

If so, 1/4 in this series can be skipped altogether.

You likely won't even need the rebinding of ti-musb-peripheral anymore.

> Cannot find a device with path /ocp/usb at 47400000/usb at 47401000
> => unbind /ocp/usb at 47400000/usb at 47401000
> => dm tree
>   misc          0  [ + ]   ti-musb-wrapper       |   |-- usb at 47400000
>   usb           0  [   ]   ti-musb-host          |   |   `-- usb at 47401800
> => fastboot usb 0
> => bind /ocp/usb at 47400000/usb at 47401000 ti-musb-peripheral
> => dm tree
>   misc          0  [ + ]   ti-musb-wrapper       |   |-- usb at 47400000
>   usb           0  [   ]   ti-musb-host          |   |   |-- usb at 47401800
>   usb           0  [   ]   ti-musb-peripheral    |   |   `-- usb at 47401000
> => fastboot usb 0
> musb-hdrc: peripheral reset irq lost!
> # works! (the irq-related line above as always been there)
> 
> So now, how do we make this process easy/understandable?

What would be your proposal ?