[PATCH RESEND v2 1/2] cmd: bind: Try to improve the (un)bind help

[Marek Vasut]

On 10/5/23 17:54, Miquel Raynal wrote:
> Hi Marek,
> 
> marex at denx.de wrote on Thu, 5 Oct 2023 15:01:51 +0200:
> 
>> On 10/2/23 15:46, Miquel Raynal wrote:
>>> While it may sound totally obvious for the regular U-Boot developer to
>>> get the parameters of the bind/unbind commands from the output of 'dm
>>> tree', it did not felt straightforward to me until I was explicitly
>>> told to look there. And even when I knew the command, I did not make a
>>> direct link between the arguments of this command and the columns
>>> returned by 'dm tree'.
>>>
>>> Several of us lost a lot of time because of that, I would like to kindly
>>> help other users by slightly improving this textual line. Unfortunately,
>>> because of how this string is used (like within the 'help' command) I
>>> cannot detail much more, but at least the pointer is there.
>>>
>>> Signed-off-by: Miquel Raynal <miquel.raynal at bootlin.com>
>>> ---
>>> Resend: no change.
>>>
>>> Changes in v2:
>>> * Moved the details in the long text section as suggested by Heinrich.
>>> * Rephrased the help text as well, not fully following Heinrich
>>>     suggestion, but taking inspiration from it.
>>> ---
>>>    cmd/bind.c | 4 ++++
>>>    1 file changed, 4 insertions(+)
>>>
>>> diff --git a/cmd/bind.c b/cmd/bind.c
>>> index 4d1b7885e60..be0d4d2a711 100644
>>> --- a/cmd/bind.c
>>> +++ b/cmd/bind.c
>>> @@ -246,6 +246,8 @@ U_BOOT_CMD(
>>>    	"Bind a device to a driver",
>>>    	"<node path> <driver>\n"
>>>    	"bind <class> <index> <driver>\n"
>>> +	"Use 'dm tree' to list all devices registered in the driver model,\n"
>>> +	"their path, class, index and current driver.\n"
>>>    );
>>>    >   U_BOOT_CMD(
>>> @@ -254,4 +256,6 @@ U_BOOT_CMD(
>>>    	"<node path>\n"
>>>    	"unbind <class> <index>\n"
>>>    	"unbind <class> <index> <driver>\n"
>>> +	"Use 'dm tree' to list all devices registered in the driver model,\n"
>>> +	"their path, class, index and current driver.\n"
>>
>> 'dm tree' depends on CMD_DM , you might need some if (IS_ENABLED()) here.
> 
> Well, no, and that's my point actually. People need to know that this
> command exist and should be used for this purpose. If you only tell
> them "use 'dm tree'" conditionally, you loose part of the audience:
> people not aware of this command or its usefulness.

If you tell them 'Use "dm tree"' and it prints "no command found" , then 
it's a bug.

You likely want to add 'imply CMD_DM' into CMD_BIND Kconfig to make sure 
CMD_DM is available by default, but also that users can turn it off if 
they really want to.