Re: [PATCH v3 4/6] drm/xe/configfs: Allow to select by class only

[Raag Jadav <raag.jadav@intel.com>]

On Tue, Sep 09, 2025 at 07:42:14AM -0500, Lucas De Marchi wrote:
> On Tue, Sep 09, 2025 at 12:27:01PM +0200, Raag Jadav wrote:
> > On Fri, Sep 05, 2025 at 10:50:32PM -0700, Lucas De Marchi wrote:
> > > For a future configfs attribute, it's desirable to select by engine mask
> > > only as the instance doesn't make sense.
> > > 
> > > Rename the function lookup_engine_mask() to lookup_engine_info() and
> > > make it return the entry. This allows parse_engine() to still return an
> > > item if the caller wants to allow parsing a class-only string like
> > > "rcs", "bcs", "ccs", etc.
> > 
> > ...
> > 
> > > -static bool lookup_engine_mask(const char *pattern, u64 *mask)
> > > +/*
> > > + * Lookup engine_info. If @mask is not NULL, reduce the mask according to the
> > > + * instance in @pattern.
> > > + *
> > > + * Examples of inputs:
> > > + * - lookup_engine_info("rcs0", &mask): return "rcs" entry from @engine_info and
> > > + *   mask == BIT_ULL(XE_HW_ENGINE_RCS0)
> > > + * - lookup_engine_info("rcs*", &mask): return "rcs" entry from @engine_info and
> > > + *   mask == XE_HW_ENGINE_RCS_MASK
> > > + * - lookup_engine_info("rcs", NULL): return "rcs" entry from @engine_info
> > > + */
> > > +static const struct engine_info *lookup_engine_info(const char *pattern, u64 *mask)
> > 
> > Now that we're returning engine_info, I'm wondering if we have any use for
> > mask parameter?
> 
> We do, because otherwise we'd have to parse the rest of the pattern in
> the caller: rcs0 vs rcs* vs rcs.

Fair.

Reviewed-by: Raag Jadav <raag.jadav@intel.com>