[PATCH v4 2/5] dt-bindings: display: ssd1307fb: Extend schema for SPI controllers

[Javier Martinez Canillas <javierm@redhat.com>]

The Solomon SSD130x OLED displays can either have an I2C or SPI interface,
add to the schema the properties and examples for OLED devices under SPI.

Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
Acked-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
---

Changes in v4:
- Add a description for the dc-gpios property for SPI (Geert Uytterhoeven)

Changes in v3:
- Add a comment to the properties required for SPI (Geert Uytterhoeven)

Changes in v2:
- Don't add compatible strings with an "-spi" suffix (Geert Uytterhoeven)

 .../bindings/display/solomon,ssd1307fb.yaml   | 42 ++++++++++++++++++-
 1 file changed, 40 insertions(+), 2 deletions(-)

diff --git a/Documentation/devicetree/bindings/display/solomon,ssd1307fb.yaml b/Documentation/devicetree/bindings/display/solomon,ssd1307fb.yaml
index 7653b6c3fcb6..3fbd87c2c120 100644
--- a/Documentation/devicetree/bindings/display/solomon,ssd1307fb.yaml
+++ b/Documentation/devicetree/bindings/display/solomon,ssd1307fb.yaml
@@ -38,9 +38,20 @@ properties:
   reset-gpios:
     maxItems: 1
 
+  # Only required for SPI
+  dc-gpios:
+    description:
+      GPIO connected to the controller's D/C# (Data/Command) pin,
+      that is needed for 4-wire SPI to tell the controller if the
+      data sent is for a command register or the display data RAM
+    maxItems: 1
+
   vbat-supply:
     description: The supply for VBAT
 
+  # Only required for SPI
+  spi-max-frequency: true
+
   solomon,height:
     $ref: /schemas/types.yaml#/definitions/uint32
     default: 16
@@ -220,14 +231,14 @@ examples:
             #address-cells = <1>;
             #size-cells = <0>;
 
-            ssd1307: oled@3c {
+            ssd1307_i2c: oled@3c {
                     compatible = "solomon,ssd1307";
                     reg = <0x3c>;
                     pwms = <&pwm 4 3000>;
                     reset-gpios = <&gpio2 7>;
             };
 
-            ssd1306: oled@3d {
+            ssd1306_i2c: oled@3d {
                     compatible = "solomon,ssd1306";
                     reg = <0x3c>;
                     pwms = <&pwm 4 3000>;
@@ -238,3 +249,30 @@ examples:
                     solomon,lookup-table = /bits/ 8 <0x3f 0x3f 0x3f 0x3f>;
             };
     };
+  - |
+    spi {
+            #address-cells = <1>;
+            #size-cells = <0>;
+
+            ssd1307_spi: oled@0 {
+                    compatible = "solomon,ssd1307";
+                    reg = <0x0>;
+                    pwms = <&pwm 4 3000>;
+                    reset-gpios = <&gpio2 7>;
+                    dc-gpios = <&gpio2 8>;
+                    spi-max-frequency = <10000000>;
+            };
+
+            ssd1306_spi: oled@1 {
+                    compatible = "solomon,ssd1306";
+                    reg = <0x1>;
+                    pwms = <&pwm 4 3000>;
+                    reset-gpios = <&gpio2 7>;
+                    dc-gpios = <&gpio2 8>;
+                    spi-max-frequency = <10000000>;
+                    solomon,com-lrremap;
+                    solomon,com-invdir;
+                    solomon,com-offset = <32>;
+                    solomon,lookup-table = /bits/ 8 <0x3f 0x3f 0x3f 0x3f>;
+            };
+    };
-- 
2.35.1