Hi Detlev, Am 09.02.22 um 20:44 schrieb Detlev Casanova: > Hi Stefan, > > On Wednesday, February 9, 2022 12:10:12 P.M. EST Stefan Wahren wrote: >> Hi Detlev, >> >> Am 09.02.22 um 17:25 schrieb Detlev Casanova: >>> Add a device tree to support the official Raspberrypi 7" touchscreen for >>> the Raspberry Pi 4 B >>> >>> The panel is connected on the DSI 1 port and uses the simple-panel >>> driver. >>> >>> The device tree also makes sure to activate: >>> * dvp: bcm2711 clock driver >>> * hvs: Hardware Video Scaler >>> * pixelvalve[0-4]: CRTC modules >>> * txp: CRTC Writeback >>> >>> Signed-off-by: Detlev Casanova <detlev.casanova@xxxxxxxxxxxxx> >>> --- >>> >>> arch/arm/boot/dts/Makefile | 1 + >>> .../boot/dts/bcm2711-rpi-4-b-7inch-ts-dsi.dts | 129 ++++++++++++++++++ >>> arch/arm64/boot/dts/broadcom/Makefile | 1 + >>> .../broadcom/bcm2711-rpi-4-b-7inch-ts-dsi.dts | 2 + >>> 4 files changed, 133 insertions(+) >>> create mode 100644 arch/arm/boot/dts/bcm2711-rpi-4-b-7inch-ts-dsi.dts >>> create mode 100644 >>> arch/arm64/boot/dts/broadcom/bcm2711-rpi-4-b-7inch-ts-dsi.dts> >>> diff --git a/arch/arm/boot/dts/Makefile b/arch/arm/boot/dts/Makefile >>> index 0de64f237cd8..b46daf2df4ce 100644 >>> --- a/arch/arm/boot/dts/Makefile >>> +++ b/arch/arm/boot/dts/Makefile >>> @@ -94,6 +94,7 @@ dtb-$(CONFIG_ARCH_BCM2835) += \ >>> >>> bcm2837-rpi-cm3-io3.dtb \ >>> bcm2711-rpi-400.dtb \ >>> bcm2711-rpi-4-b.dtb \ >>> >>> + bcm2711-rpi-4-b-7inch-ts-dsi.dtb \ >>> >>> bcm2711-rpi-cm4-io.dtb \ >>> bcm2835-rpi-zero.dtb \ >>> bcm2835-rpi-zero-w.dtb >>> >>> diff --git a/arch/arm/boot/dts/bcm2711-rpi-4-b-7inch-ts-dsi.dts >>> b/arch/arm/boot/dts/bcm2711-rpi-4-b-7inch-ts-dsi.dts new file mode 100644 >>> index 000000000000..62e986358c2a >>> --- /dev/null >>> +++ b/arch/arm/boot/dts/bcm2711-rpi-4-b-7inch-ts-dsi.dts >> i think this should be an overlay because this board can be connected to >> different boards and we want to avoid copy & paste. Unfortunately i >> don't know where this should be stored in the kernel tree. > Yes, that is how it started but the upstream kernel doesn't use them. We > thought that a separate device-tree makes sense as it is the official raspberry > pi touchscreen. i'm not an expert here, but this seems not quite correct. AFAIK there is no full runtime overlay support in the kernel, but the resources that i found are promising [1], [2], [3]. Unfortunately i never test it by myself. Please understand that all these possible combination would result in a unmaintable mess. Best regards [1] - https://u-boot.readthedocs.io/en/latest/usage/fdt_overlays.html [2] - https://www.kernel.org/doc/html/latest/devicetree/overlay-notes.html [3] - https://bootlin.com/pub/conferences/2021/lee/maincent-devicetree-overlay-and-uboot-extension-board-management/maincent-devicetree-overlay-and-uboot-extension-board-management.pdf
