[PATCH v2 03/16] dt-bindings: display: renesas: lvds: Add EXTAL and DU_DOTCLKIN clocks

[Laurent Pinchart]

On the D3 and E3 SoCs, the LVDS encoder can derive its internal pixel
clock from an externally supplied clock, either through the EXTAL pin or
through one of the DU_DOTCLKINx pins. Add corresponding clocks to the DT
bindings.

To retain backward compatibility with DT that don't specify the
clock-names property, the functional clock must always be specified
first, and the clock-names property is optional when only the functional
clock is specified.

Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas at ideasonboard.com>
Reviewed-by: Jacopo Mondi <jacopo+renesas at jmondi.org>
---
Changes since v1:

- Clarified wording
---
 .../devicetree/bindings/display/bridge/renesas,lvds.txt      | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/Documentation/devicetree/bindings/display/bridge/renesas,lvds.txt b/Documentation/devicetree/bindings/display/bridge/renesas,lvds.txt
index 13af7e2ac7e8..3aeb0ec06fd0 100644
--- a/Documentation/devicetree/bindings/display/bridge/renesas,lvds.txt
+++ b/Documentation/devicetree/bindings/display/bridge/renesas,lvds.txt
@@ -19,7 +19,17 @@ Required properties:
   - "renesas,r8a77995-lvds" for R8A77995 (R-Car D3) compatible LVDS encoders
 
 - reg: Base address and length for the memory-mapped registers
-- clocks: A phandle + clock-specifier pair for the functional clock
+- clocks: A list of phandles + clock-specifier pairs, one for each entry in
+  the clock-names property.
+- clock-names: Name of the clocks. This property is model-dependent.
+  - The functional clock, which mandatory for all models, shall be listed
+    first, and shall be named "fck".
+  - On R8A77990 and R8A77995, the LVDS encoder can use the EXTAL or
+    DU_DOTCLKINx clocks. Those clocks are optional. When supplied they must be
+    named "extal" and "dclkin.x" respectively, with "x" being the DU_DOTCLKIN
+    numerical index.
+  - When the clocks property only contains the functional clock, the
+    clock-names property may be omitted.
 - resets: A phandle + reset specifier for the module reset
 
 Required nodes:
-- 
Regards,

Laurent Pinchart