Hi Alexander, On Fri, Feb 04, 2022 at 09:50:06AM +0100, Alexander Stein wrote: > Am Donnerstag, 3. Februar 2022, 18:50:00 CET schrieb Jean-Michel Hautbois: > > Introduce the dt-bindings documentation for bcm2835 CCP2/CSI2 Unicam > > camera interface. Also add a MAINTAINERS entry for it. > > > > Signed-off-by: Dave Stevenson <dave.stevenson@xxxxxxxxxxxxxxx> > > Signed-off-by: Naushir Patuck <naush@xxxxxxxxxxxxxxx> > > Signed-off-by: Jean-Michel Hautbois <jeanmichel.hautbois@xxxxxxxxxxxxxxxx> > > > > --- > > 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 | 110 ++++++++++++++++++ > > 1 file changed, 110 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..0725a0267c60 > > --- /dev/null > > +++ b/Documentation/devicetree/bindings/media/brcm,bcm2835-unicam.yaml > > @@ -0,0 +1,110 @@ > > +# 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@xxxxxxxxxxxxxxx> > > + > > +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 starting by 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. > > + > > + 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 data lanes on the csi bus > > There is already data-lanes in Documentation/devicetree/bindings/media/video- > interfaces.yaml. AFAICS these two are identical. Can't the video- > interface.yaml be used for this? I'm no expert TBH. This is the number of data lanes that the Unicam instance supports. There are two Unicam instances, and they can have 2 or 4 data lanes depending on the SoC. The data-lanes endpoint property indicates the number of lanes used on a particular board. -- Regards, Laurent Pinchart
