`uclass_find_device_by_name` fails to find the device

[Simon Glass]

Hi Nandor,

On Tue, 7 Jan 2020 at 02:16, Nandor Han <nandor.han at vaisala.com> wrote:
>
>
> Hi Simon and thanks,
>
> On 2019-12-24 17:58, Simon Glass wrote:
>
> <snip>
>
> >
> > Can you use a phandle to refer to the device from another node,
> > perhaps a UCLASS_BOARD node if needed? It is not a good idea to use
> > this function.
>
> I'm not sure, I'll have to check that.

OK, that is the preferred method.

> Anyway
> `uclass_find_device_by_name` is used by `uclass_get_device_by_name`,
> which already seems to be used in plenty of places.
>
> >
> > Alternatively we could add a new function which finds by partial name.
>
> My fix was to ignore the suffix starting from "@", if that exist, since
> that's more like metadata...and compare entire string when "@" is missing.
>
> Something like:
>
>          uclass_foreach_dev(dev, uc) {
> -               if (!strcmp(dev->name, name)) {
> +               char *at_char = strchr(dev->name, '@');
> +               int name_length;
> +
> +               if (at_char)
> +                       name_length = at_char - dev->name;
> +               else
> +                       name_length = max(strlen(dev->name), strlen(name));
> +
> +               if (!strncmp(dev->name, name, name_length)) {
>                          *devp = dev;
>                          return 0;
>                  }
>
> I could probably to prepare an RFC with this change.

I think this is OK as a new function, but do add a comment in the
header that it should not be used and phandles should be used instead.
Also please remember to add a test.

Regards,
Simon