[U-Boot] [PATCH v3 7/7] cmd: Add bind/unbind commands to bind a device to a driver from the command line

[Michal Simek]

On 30.6.2018 06:19, Simon Glass wrote:
> On 27 June 2018 at 07:13, Michal Simek <michal.simek at xilinx.com> wrote:
>> On 22.6.2018 14:25, Jean-Jacques Hiblot wrote:
>>> In some cases it can be useful to be able to bind a device to a driver from
>>> the command line.
>>> The obvious example is for versatile devices such as USB gadget.
>>> Another use case is when the devices are not yet ready at startup and
>>> require some setup before the drivers are bound (ex: FPGA which bitsream is
>>> fetched from a mass storage or ethernet)
>>>
>>> usage example:
>>>
>>> bind usb_dev_generic 0 usb_ether
>>> unbind usb_dev_generic 0 usb_ether
>>> or
>>> unbind eth 1
>>>
>>> bind /ocp/omap_dwc3 at 48380000/usb at 48390000 usb_ether
>>> unbind /ocp/omap_dwc3 at 48380000/usb at 48390000
>>>
>>> Signed-off-by: Jean-Jacques Hiblot <jjhiblot at ti.com>
>>>
>>> ---
>>>
>>> Changes in v3:
>>> - factorize code based on comments from ML
>>> - remove the devices before unbinding them
>>> - use device_find_global_by_ofnode() to get a device by its node.
>>> - Added tests
>>>
>>> Changes in v2:
>>> - Make the bind/unbind command generic, not specific to usb device.
>>> - Update the API to be able to bind/unbind based on DTS node path
>>> - Add a Kconfig option to select the bind/unbind commands
>>>
>>>  arch/sandbox/dts/test.dts  |  11 ++
>>>  cmd/Kconfig                |   9 ++
>>>  cmd/Makefile               |   1 +
>>>  cmd/bind.c                 | 255 +++++++++++++++++++++++++++++++++++++++++++++
>>>  configs/sandbox_defconfig  |   1 +
>>>  test/py/tests/test_bind.py | 178 +++++++++++++++++++++++++++++++
>>>  6 files changed, 455 insertions(+)
>>>  create mode 100644 cmd/bind.c
>>>  create mode 100644 test/py/tests/test_bind.py
> 
> Reviewed-by: Simon Glass <sjg at chromium.org>
> 
> Nice work
> 
> [...]
> 
>>
>> I have tested bind/unbind with dwc3 on zynqmp for ethernet gadget and it
>> is working fine for me.
>> I have also tried to use bind/unbind for gpio zynqmp driver and it is
>> also working fine.
>>
>> It means
>> Tested-by: Michal Simek <michal.simek at xilinx.com>
>>
>> I would prefer if these commands are called as dm bind and dm unbind
>> instead of simply bind/unbind which should also fit to dm command
>> description "dm - Driver model low level access".
> 
> Yes i can see the point. But after thinking about it, maybe it is best
> as it is? After all driver model is fundamental to U-Boot and it's not
> clear what else we might bind/unbind.
> 
> I'd like to get other opinions here, too.

Tom/Marek: Any opinion?

Thanks,
Michal