drm: rcar-du: Fix external clock error checks

The rcar-du driver supports probe deferral for external clocks, but
implements it badly by checking the wrong pointer due to a bad copy and
paste. Fix it.

While at it, reject invalid clocks outright for DU channels that have a
display PLL, as the external clock is mandatory in that case. This
avoids a WARN_ON() at runtime.

Fixes: 1b30dbde8596 ("drm: rcar-du: Add support for external pixel clock")
Reported-by: Kuninori Morimoto <[email protected]>
Signed-off-by: Laurent Pinchart <[email protected]>
Reviewed-by: Kieran Bingham <[email protected]>

0 files changed, 0 insertions, 0 deletions