[PATCH/RFC] serial: sh-sci: Add device tree support for r8a7779

Laurent Pinchart laurent.pinchart at ideasonboard.com
Tue Apr 29 06:44:46 PDT 2014


Hi Simon,

On Monday 28 April 2014 16:07:49 Simon Horman wrote:
> On Mon, Apr 28, 2014 at 10:13:55AM +0900, Simon Horman wrote:
> > On Mon, Apr 28, 2014 at 02:08:16AM +0200, Laurent Pinchart wrote:
> > > On Monday 28 April 2014 09:03:14 Simon Horman wrote:
> > > > On Fri, Apr 25, 2014 at 09:11:06AM +0200, Geert Uytterhoeven wrote:
> > > > > On Fri, Apr 25, 2014 at 9:05 AM, Laurent Pinchart wrote:
> > > > > >> +     scif0: serial at ffe40000 {
> > > > > >> +             compatible = "renesas,scif",
> > > > > >> "renesas,scif-r8a7779";
> > > > > >> +             reg = <0xffe40000 265>;
> > > > > >> +             interrupt-parent = <&gic>;
> > > > > >> +             interrupts = <0 88 IRQ_TYPE_LEVEL_HIGH>;
> > > > > >> +             clocks = <&cpg_clocks R8A7779_CLK_P>;
> > > > > >> +             clock-names = "sci_ick";
> > > > > > 
> > > > > > Clock handling in the sh-sci driver should probably be improved.
> > > > > > The driver currently requires an "sci_ick" interface clock and
> > > > > > supports an optional "sci_fck" functional clock. In practice, as
> > > > > > far as I can see, platforms that provide both sci_ick and sci_fck
> > > > > > set the two clocks to the same source.
> > > > > 
> > > > > That's right. As a consequence, the clock's enable count is
> > > > > incremented
> > > > > 
> > > > > 3 times:
> > > > >   - once for fck,
> > > > >   - once for ick,
> > > > >   - once for generic Runtime PM using the "NULL" clock.
> > > > 
> > > > This approach is fine by me.
> > > > But I think you need to maintain compatibility with the old
> > > > binding ("sci_ick" required, "sci_fsk") as it seems that
> > > > was included in v3.14.
> > > 
> > > sci_fck isn't part of the DT bindings, so we can at least drop that one.
> > 
> > So long as its not used anywhere in-tree, which I believe is the case,
> > then that is fine by me.
> 
> BTW, are you planning to make the above mentioned driver update
> before or after re-posting enablement patches for Koelsch and/or Lager?
> I ask because I would like to make such patches the basis for
> a patch for Marzen.

I'll try to do so today, after my talk at the ELC :-)

-- 
Regards,

Laurent Pinchart




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