Re: [PATCH 05/16] drm: rcar-du: lvds: D3/E3 support

[Laurent Pinchart <laurent.pinchart@ideasonboard.com>]

Hi Geert,

On Tuesday, 4 September 2018 17:29:29 EEST Geert Uytterhoeven wrote:
> On Tue, Sep 4, 2018 at 2:10 PM Laurent Pinchart wrote:
> > The LVDS encoders in the D3 and E3 SoCs differ significantly from those
> > in the other R-Car Gen3 family members:
> > 
> > - The LVDS PLL architecture is more complex and requires computing PLL
> >   parameters manually.
> > 
> > - The PLL uses external clocks as inputs, which need to be retrieved
> >   from DT.
> > 
> > - In addition to the different PLL setup, the startup sequence has
> >   changed *again* (seems someone had trouble making his/her mind).
> > 
> > Supporting all this requires DT bindings extensions for external clocks,
> > brand new PLL setup code, and a few quirks to handle the differences in
> > the startup sequence.
> > 
> > The implementation doesn't support all hardware features yet, namely
> > 
> > - Using the LV[01] clocks generated by the CPG as PLL input.
> > - Providing the LVDS PLL clock to the DU for use with the RGB output.
> > 
> > Those features can be added later when the need will arise.
> > 
> > Signed-off-by: Laurent Pinchart
> > <laurent.pinchart+renesas@ideasonboard.com>
> 
> Thanks for your patch!
> 
> > --- a/drivers/gpu/drm/rcar-du/rcar_lvds.c
> > +++ b/drivers/gpu/drm/rcar-du/rcar_lvds.c
> > 
> > +static void rcar_lvds_d3_e3_pll_calc(struct rcar_lvds *lvds, struct clk
> > *clk, +                                    unsigned long target, struct
> > pll_info *pll) +{
> > 
> > +#if defined(CONFIG_DEBUG) || defined(CONFIG_DYNAMIC_DEBUG)
> > +       {
> 
> As this code has no dependencies, you can improve compile coverage:
> 
>     if (IS_ENABLED(...) || ...) {
> 
> BTW, was CONFIG_DEBUG intended? Or just DEBUG?

It should have been just DEBUG, yes.

I was trying to guard against dev_dbg() being defined as a no-op and gcc 
throwing unused variables warnings, but it looks like that has never been an 
issue in the first place, so I'll drop the guard.

-- 
Regards,

Laurent Pinchart