[PATCH v5 03/11] dt-bindings: media: Add bindings for bcm2835-unicam

Jean-Michel Hautbois
2022-02-08T15:51:01Z

Introduce the dt-bindings documentation for bcm2835 CCP2/CSI2 Unicam
camera interface.

Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
Signed-off-by: Naushir Patuck <naush@raspberrypi.com>
Signed-off-by: Jean-Michel Hautbois <jeanmichel.hautbois@ideasonboard.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>

---
v4:
- make MAINTAINERS its own patch
- describe the reg and clocks correctly
- use a vendor entry for the number of data lanes
---
.../bindings/media/brcm,bcm2835-unicam.yaml | 117 ++++++++++++++++++
1 file changed, 117 insertions(+)
create mode 100644 Documentation/devicetree/bindings/media/brcm,bcm2835-unicam.yaml

diff --git a/Documentation/devicetree/bindings/media/brcm,bcm2835-unicam.yaml b/Documentation/devicetree/bindings/media/brcm,bcm2835-unicam.yaml
new file mode 100644
index 000000000000..1938ace23b3d
--- /dev/null
+++ b/Documentation/devicetree/bindings/media/brcm,bcm2835-unicam.yaml
@@ -0,0 +1,117 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/media/brcm,bcm2835-unicam.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Broadcom BCM283x Camera Interface (Unicam)
+
+maintainers:
+ - Raspberry Pi Kernel Maintenance <kernel-list@raspberrypi.com>
+
+description: |-
+ The Unicam block on BCM283x SoCs is the receiver for either
+ CSI-2 or CCP2 data from image sensors or similar devices.
+
+ The main platform using this SoC is the Raspberry Pi family of boards. On
+ the Pi the VideoCore firmware can also control this hardware block, and
+ driving it from two different processors will cause issues. To avoid this,
+ the firmware checks the device tree configuration during boot. If it finds
+ device tree nodes whose name starts with 'csi' then it will stop the firmware
+ accessing the block, and it can then safely be used via the device tree
+ binding.
+
+properties:
+ compatible:
+ const: brcm,bcm2835-unicam
+
+ reg:
+ items:
+ - description: Unicam block.
+ - description: Clock Manager Image (CMI) block.
+
+ reg-names:
+ items:
+ - const: unicam
+ - const: cmi
+
+ interrupts:
+ maxItems: 1
+
+ clocks:
+ items:
+ - description: Clock to drive the LP state machine of Unicam.
+ - description: Clock for the VPU (core clock).
+
+ clock-names:
+ items:
+ - const: lp
+ - const: vpu
+
+ power-domains:
+ items:
+ - description: Unicam power domain
+
+ brcm,num-data-lanes:
+ $ref: /schemas/types.yaml#/definitions/uint32
+ enum: [ 2, 4 ]
+ description: |
+ Number of CSI-2 data lanes supported by this Unicam instance. The number
+ of data lanes actively used is specified with the data-lanes endpoint
+ property.
+
+ port:
+ $ref: /schemas/graph.yaml#/$defs/port-base
+ unevaluatedProperties: false
+
+ properties:
+ endpoint:
+ $ref: /schemas/media/video-interfaces.yaml#
+ unevaluatedProperties: false
+
+ properties:
+ data-lanes: true
+
+ required:
+ - data-lanes
+
+ required:
+ - endpoint
+
+required:
+ - compatible
+ - reg
+ - reg-names
+ - interrupts
+ - clocks
+ - clock-names
+ - power-domains
+ - brcm,num-data-lanes
+ - port
+
+additionalProperties: False
+
+examples:
+ - |
+ #include <dt-bindings/clock/bcm2835.h>
+ #include <dt-bindings/interrupt-controller/arm-gic.h>
+ #include <dt-bindings/power/raspberrypi-power.h>
+ csi1: csi@7e801000 {
+ compatible = "brcm,bcm2835-unicam";
+ reg = <0x7e801000 0x800>,
+ <0x7e802004 0x4>;
+ reg-names = "unicam", "cmi";
+ interrupts = <GIC_SPI 103 IRQ_TYPE_LEVEL_HIGH>;
+ clocks = <&clocks BCM2835_CLOCK_CAM1>,
+ <&firmware_clocks 4>;
+ clock-names = "lp", "vpu";
+ power-domains = <&power RPI_POWER_DOMAIN_UNICAM1>;
+ brcm,num-data-lanes = <2>;
+ port {
+ csi1_ep: endpoint {
+ remote-endpoint = <&imx219_0>;
+ data-lanes = <1 2>;
+ };
+ };
+ };
+...
--
2.32.0