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

From: Sakari Ailus
Date: Mon Dec 28 2020 - 11:43:23 EST


Hi Daniel,

On Thu, Dec 24, 2020 at 02:21:15PM +0000, Daniel Scally wrote:
> 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 :)

I'd be in favour of using strlen("port@") here.

At least for now. I think refactoring the use of such strings could be a
separate set at another time, if that's seen as the way to go.

--
Kind regards,

Sakari Ailus