Re: [PATCH v3 07/14] software_node: Add support for fwnode_graph*() family of functions

[Daniel Scally]

Hi Andy, Laurent

> On Thu, Dec 24, 2020 at 2:55 PM Laurent Pinchart
> <laurent.pinchart@xxxxxxxxxxxxxxxx> wrote:
>> On Thu, Dec 24, 2020 at 02:24:12PM +0200, Andy Shevchenko wrote:
>>> On Thu, Dec 24, 2020 at 3:14 AM Daniel Scally wrote:
> 
> ...
> 
>>>> +               if (!strncmp(to_swnode(port)->node->name, "port@",
>>>
>>> You may use here corresponding _FMT macro.
>>>
>>>> +                            FWNODE_GRAPH_PORT_NAME_PREFIX_LEN))
>>>> +                       return port;
> 
> ...
> 
>>>> +       /* Ports have naming style "port@n", we need to select the n */
>>>
>>>> +       ret = kstrtou32(swnode->parent->node->name + FWNODE_GRAPH_PORT_NAME_PREFIX_LEN,
>>>
>>> Maybe a temporary variable?
>>>
>>>   unsigned int prefix_len = FWNODE_GRAPH_PORT_NAME_PREFIX_LEN;
>>>   ...
>>>   ret = kstrtou32(swnode->parent->node->name + prefix_len,
>>
>> Honestly I'm wondering if those macros don't hinder readability. I'd
>> rather write
>>
>>         + strlen("port@")
> 
> Works for me, since the compiler optimizes this away to be a plain constant.

Well, how about instead of the LEN macro, we have:

#define FWNODE_GRAPH_PORT_NAME_PREFIX	"port@"
#define FWNODE_GRAPH_PORT_NAME_FMT FWNODE_GRAPH_PORT_NAME_PREFIX "%u"

And then it's still maintainable in one place but (I think) slightly
less clunky, since we can do strlen(FWNODE_GRAPH_PORT_NAME_PREFIX)

Or we can do strlen("port@"), I'm good either way :)