Re: [RESEND PATCH v3 1/2] device property: Add function to search for named child of device

From: Rafael J. Wysocki
Date: Tue Jun 21 2016 - 11:07:29 EST


On Tuesday, June 21, 2016 11:50:01 AM Opensource [Adam Thomson] wrote:
> 21 June 2016 12:42, Rafael J. Wysocki wrote:
>
> > > > +static inline bool acpi_data_node_match(struct fwnode_handle *fwnode,
> > > > + const char *name)
> > > > +{
> > > > + return is_acpi_data_node(fwnode) ?
> > > > + (!strcasecmp(to_acpi_data_node(fwnode)->name, name)) : false;
> > > > +}
> > >
> > > Looks fine to me.
> > >
> > > One question - is it expected that matching ACPI data nodes is always
> > > case insensitive?
> >
> > That would not be a correct expectation in theory, although I don't think it
> > really matters in practice.
>
> From my reading of the Hierarchical Data Extension and ACPI Spec, I thought
> that was the case (section 19.3.1 ASL Names - ASL names are not case-sensitive
> and will be converted to upper case).

Section 19.3.1 is applicable to object names and not to the data returned
by those objects. The link names in the Hierarchical Data Extension are
data returned by _DSD (or other objects related to it). They are general ACPI
strings and those are case-sensitive.

Thanks,
Rafael