Re: [PATCH v11 4/7] drm/sun4i: dsi: Handle bus clock explicitly

[Jagan Teki <jagan@amarulasolutions.com>]

Hi Maxime,

On Mon, Oct 28, 2019 at 9:06 PM Maxime Ripard <mripard@kernel.org> wrote:
>
> On Fri, Oct 25, 2019 at 11:26:22PM +0530, Jagan Teki wrote:
> > Usage of clocks are varies between different Allwinner
> > DSI controllers. Clocking in A33 would need bus and
> > mod clocks where as A64 would need only bus clock.
> >
> > To support this kind of clocking structure variants
> > in the same dsi driver,
>
> There's no variance in the clock structure as far as the bus clock is
> concerned.
>
> > explicit handling of common clock would require since the A64
> > doesn't need to mention the clock-names explicitly in dts since it
> > support only one bus clock.
> >
> > Also pass clk_id NULL instead "bus" to regmap clock init function
> > since the single clock variants no need to mention clock-names
> > explicitly.
>
> You don't need explicit clock handling. Passing NULL as the argument
> in regmap_init_mmio_clk will make it use the first clock, which is the
> bus clock.

Indeed I tried that, since NULL clk_id wouldn't enable the bus clock
during regmap_mmio_gen_context code, passing NULL triggering vblank
timeout.