[PATCH v3 2/3] spi: dt-bindings: atmel,at91rm9200-spi: Add support for optional 'spi_gclk' clock

[Manikandan Muralidharan <manikandan.m@microchip.com>]

The Atmel SPI controller supports both the peripheral clock and the
Generic Clock (GCLK) as sources for SPCK generation. On platforms like
the SAM9X7 SoC, the peripheral clock can reach frequencies up to
266 MHz, which may exceed the maximum value supported by the Serial
Clock Baud Rate (SCBR) divider, leading to SPI transfer failures. In such
cases, the GCLK can be used as an alternative source for SPCK generation"

This patch updates the Atmel SPI DT binding to support an optional
programmable SPI generic clock, specified as 'spi_gclk', in addition to
the required 'spi_clk'.

Signed-off-by: Manikandan Muralidharan <manikandan.m@microchip.com>
---
 .../devicetree/bindings/spi/atmel,at91rm9200-spi.yaml | 11 ++++++++---
 1 file changed, 8 insertions(+), 3 deletions(-)

diff --git a/Documentation/devicetree/bindings/spi/atmel,at91rm9200-spi.yaml b/Documentation/devicetree/bindings/spi/atmel,at91rm9200-spi.yaml
index d29772994cf5..11885d0cc209 100644
--- a/Documentation/devicetree/bindings/spi/atmel,at91rm9200-spi.yaml
+++ b/Documentation/devicetree/bindings/spi/atmel,at91rm9200-spi.yaml
@@ -31,11 +31,16 @@ properties:
     maxItems: 1
 
   clock-names:
-    contains:
-      const: spi_clk
+    items:
+      - const: spi_clk
+      - const: spi_gclk
+    minItems: 1
 
   clocks:
-    maxItems: 1
+    items:
+      - description: Peripheral Bus clock
+      - description: Programmable Generic clock
+    minItems: 1
 
   dmas:
     items:
-- 
2.25.1