dt-bindings: clock: Add a binding for the RPi Firmware clocks

The firmware running on the RPi VideoCore can be used to discover and
change the various clocks running in the BCM2711. Since devices will
need to use them through the DT, let's add a pretty simple binding.

Cc: Michael Turquette <mturquette@baylibre.com>
Cc: linux-clk@vger.kernel.org
Cc: devicetree@vger.kernel.org
Reviewed-by: Stephen Boyd <sboyd@kernel.org>
Reviewed-by: Rob Herring <robh+dt@kernel.org>
Tested-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://lore.kernel.org/r/f6105207e7ef5a5ea8d7a1774faf989d341a25f5.1592210452.git-series.maxime@cerno.tech
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

diff --git a/Documentation/devicetree/bindings/arm/bcm/raspberrypi,bcm2835-firmware.yaml b/Documentation/devicetree/bindings/arm/bcm/raspberrypi,bcm2835-firmware.yaml
index cec540c052b6ac0ed8632d9c2697d25810bf26f7..b48ed875eb8e4535f716ac976afb53f724d29de3 100644 (file)
--- a/Documentation/devicetree/bindings/arm/bcm/raspberrypi,bcm2835-firmware.yaml
+++ b/Documentation/devicetree/bindings/arm/bcm/raspberrypi,bcm2835-firmware.yaml
@@ -22,6 +22,25 @@ properties:
       Phandle to the firmware device's Mailbox.
       (See: ../mailbox/mailbox.txt for more information)
 
+  clocks:
+    type: object
+
+    properties:
+      compatible:
+        const: raspberrypi,firmware-clocks
+
+      "#clock-cells":
+        const: 1
+        description: >
+          The argument is the ID of the clocks contained by the
+          firmware messages.
+
+    required:
+      - compatible
+      - "#clock-cells"
+
+    additionalProperties: false
+
 required:
   - compatible
   - mboxes
@@ -31,5 +50,10 @@ examples:
     firmware {
         compatible = "raspberrypi,bcm2835-firmware", "simple-bus";
         mboxes = <&mailbox>;
+
+        firmware_clocks: clocks {
+            compatible = "raspberrypi,firmware-clocks";
+            #clock-cells = <1>;
+        };
     };
 ...