[RFC PATCH v2 0/3] ARM: dts: Support official Raspberry Pi 7inch touchscreen

[RFC PATCH v2 0/3] ARM: dts: Support official Raspberry Pi 7inch touchscreen

[Detlev Casanova]

Add a devicetree overlay to support the official Raspberry Pi 7inch touchscreen.

This also demuxes the i2c0 controller to support both pinctrls.

Changes in v2:
 * The device tree in now an overlay
 * The i2c demux patch is kept for now to have a working patch set. It has
   not been merged yet in [1].
 * The device tree overlay doesn't use fragments. It is working as is 
   but not enough literature was found to go one way or the other.

[1] https://www.spinics.net/lists/arm-kernel/msg944330.html

Detlev Casanova (3):
  ARM: dts: bcm2*: Demux i2c0 with a pinctrl
  of: Add support for -@ when compiling overlays
  ARM: dto: Add bcm2711-rpi-7-inches-ts.dts overlay

 arch/arm/boot/dts/Makefile                    |   4 +
 arch/arm/boot/dts/bcm2711-rpi-4-b.dts         |   1 +
 arch/arm/boot/dts/bcm2711.dtsi                |   2 +-
 arch/arm/boot/dts/bcm2835-rpi.dtsi            |   9 +-
 .../boot/dts/bcm283x-rpi-i2c0mux_0_44.dtsi    |   4 +
 arch/arm/boot/dts/bcm283x.dtsi                |  26 +++-
 arch/arm/boot/dts/overlays/Makefile           |   3 +
 .../dts/overlays/bcm2711-rpi-7-inches-ts.dts  | 125 ++++++++++++++++++
 arch/arm64/boot/dts/broadcom/Makefile         |   4 +
 .../arm64/boot/dts/broadcom/overlays/Makefile |   3 +
 .../overlays/bcm2711-rpi-7-inches-ts.dts      |   2 +
 drivers/of/Kconfig                            |   8 ++
 scripts/Makefile.lib                          |   9 +-
 13 files changed, 193 insertions(+), 7 deletions(-)
 create mode 100644 arch/arm/boot/dts/bcm283x-rpi-i2c0mux_0_44.dtsi
 create mode 100644 arch/arm/boot/dts/overlays/Makefile
 create mode 100644 arch/arm/boot/dts/overlays/bcm2711-rpi-7-inches-ts.dts
 create mode 100644 arch/arm64/boot/dts/broadcom/overlays/Makefile
 create mode 100644 arch/arm64/boot/dts/broadcom/overlays/bcm2711-rpi-7-inches-ts.dts

-- 
2.36.0

[RFC PATCH v2 1/3] ARM: dts: bcm2*: Demux i2c0 with a pinctrl

[Detlev Casanova]

The i2c0 device has 2 different busses controlled by a pinctrl.
This commit separates the device node into 2 i2c devices:
 * pin 0: Base i2c bus
 * pin 44: DSI i2c bus

i2c0 is renamed to i2c0if so that device-trees referencing i2c0 don't
break and use the i2c0 node defined in i2c0mux node.

i2c_csi_dsi can be used to control devices via the DSI i2c bus, used for
DSI displays.

Signed-off-by: Detlev Casanova <detlev.casanova@collabora.com>
---
 arch/arm/boot/dts/bcm2711-rpi-4-b.dts         |  1 +
 arch/arm/boot/dts/bcm2711.dtsi                |  2 +-
 arch/arm/boot/dts/bcm2835-rpi.dtsi            |  9 ++++---
 .../boot/dts/bcm283x-rpi-i2c0mux_0_44.dtsi    |  4 +++
 arch/arm/boot/dts/bcm283x.dtsi                | 26 ++++++++++++++++++-
 5 files changed, 37 insertions(+), 5 deletions(-)
 create mode 100644 arch/arm/boot/dts/bcm283x-rpi-i2c0mux_0_44.dtsi

diff --git a/arch/arm/boot/dts/bcm2711-rpi-4-b.dts b/arch/arm/boot/dts/bcm2711-rpi-4-b.dts
index 4432412044de..5dcce58817e6 100644
--- a/arch/arm/boot/dts/bcm2711-rpi-4-b.dts
+++ b/arch/arm/boot/dts/bcm2711-rpi-4-b.dts
@@ -4,6 +4,7 @@
 #include "bcm2711-rpi.dtsi"
 #include "bcm283x-rpi-usb-peripheral.dtsi"
 #include "bcm283x-rpi-wifi-bt.dtsi"
+#include "bcm283x-rpi-i2c0mux_0_44.dtsi"
 
 / {
 	compatible = "raspberrypi,4-model-b", "brcm,bcm2711";
diff --git a/arch/arm/boot/dts/bcm2711.dtsi b/arch/arm/boot/dts/bcm2711.dtsi
index dff18fc9a906..96209ed89c36 100644
--- a/arch/arm/boot/dts/bcm2711.dtsi
+++ b/arch/arm/boot/dts/bcm2711.dtsi
@@ -1045,7 +1045,7 @@ &cma {
 	alloc-ranges = <0x0 0x00000000 0x40000000>;
 };
 
-&i2c0 {
+&i2c0if {
 	compatible = "brcm,bcm2711-i2c", "brcm,bcm2835-i2c";
 	interrupts = <GIC_SPI 117 IRQ_TYPE_LEVEL_HIGH>;
 };
diff --git a/arch/arm/boot/dts/bcm2835-rpi.dtsi b/arch/arm/boot/dts/bcm2835-rpi.dtsi
index 87ddcad76083..1e38f9f0e80e 100644
--- a/arch/arm/boot/dts/bcm2835-rpi.dtsi
+++ b/arch/arm/boot/dts/bcm2835-rpi.dtsi
@@ -49,13 +49,16 @@ alt0: alt0 {
 	};
 };
 
-&i2c0 {
-	pinctrl-names = "default";
-	pinctrl-0 = <&i2c0_gpio0>;
+&i2c0if {
 	status = "okay";
 	clock-frequency = <100000>;
 };
 
+&i2c0mux {
+	pinctrl-0 = <&i2c0_gpio0>;
+	status = "okay";
+};
+
 &i2c1 {
 	pinctrl-names = "default";
 	pinctrl-0 = <&i2c1_gpio2>;
diff --git a/arch/arm/boot/dts/bcm283x-rpi-i2c0mux_0_44.dtsi b/arch/arm/boot/dts/bcm283x-rpi-i2c0mux_0_44.dtsi
new file mode 100644
index 000000000000..119946d878db
--- /dev/null
+++ b/arch/arm/boot/dts/bcm283x-rpi-i2c0mux_0_44.dtsi
@@ -0,0 +1,4 @@
+&i2c0mux {
+	pinctrl-0 = <&i2c0_gpio0>;
+	pinctrl-1 = <&i2c0_gpio44>;
+};
diff --git a/arch/arm/boot/dts/bcm283x.dtsi b/arch/arm/boot/dts/bcm283x.dtsi
index c113661a6668..62d7ee513549 100644
--- a/arch/arm/boot/dts/bcm283x.dtsi
+++ b/arch/arm/boot/dts/bcm283x.dtsi
@@ -336,7 +336,7 @@ spi: spi@7e204000 {
 			status = "disabled";
 		};
 
-		i2c0: i2c@7e205000 {
+		i2c0if: i2c@7e205000 {
 			compatible = "brcm,bcm2835-i2c";
 			reg = <0x7e205000 0x200>;
 			interrupts = <2 21>;
@@ -346,6 +346,30 @@ i2c0: i2c@7e205000 {
 			status = "disabled";
 		};
 
+		i2c0mux: i2c0mux {
+			compatible = "i2c-mux-pinctrl";
+			#address-cells = <1>;
+			#size-cells = <0>;
+
+			i2c-parent = <&i2c0if>;
+
+			pinctrl-names = "i2c0", "i2c_csi_dsi";
+
+			status = "disabled";
+
+			i2c0: i2c@0 {
+				reg = <0>;
+				#address-cells = <1>;
+				#size-cells = <0>;
+			};
+
+			i2c_csi_dsi: i2c@1 {
+				reg = <1>;
+				#address-cells = <1>;
+				#size-cells = <0>;
+			};
+		};
+
 		dpi: dpi@7e208000 {
 			compatible = "brcm,bcm2835-dpi";
 			reg = <0x7e208000 0x8c>;
-- 
2.36.0

[RFC PATCH v2 2/3] of: Add support for -@ when compiling overlays

[Detlev Casanova]

This commit adds an option to compile all device trees with -@ to add the
symbol table to the Device Tree Blobs.

It prepares the introduction of device tree overlays that are
not applied on device trees at compile time (dtbo files.)

These device tree overlays will be used by either a bootloader or a
linux userspace tool to extend the base device tree.

This is used e.g. for drivers that need device tree nodes for optional
non plug and play devices, like an external DSI touchscreen panel that
embeds different i2c devices to control it.

Signed-off-by: Detlev Casanova <detlev.casanova@collabora.com>
---
 drivers/of/Kconfig   | 8 ++++++++
 scripts/Makefile.lib | 9 +++++++--
 2 files changed, 15 insertions(+), 2 deletions(-)

diff --git a/drivers/of/Kconfig b/drivers/of/Kconfig
index 80b5fd44ab1c..28cf8d18ac45 100644
--- a/drivers/of/Kconfig
+++ b/drivers/of/Kconfig
@@ -76,11 +76,19 @@ config OF_RESERVED_MEM
 config OF_RESOLVE
 	bool
 
+config OF_SYMBOLS
+	bool "Include device tree symbols"
+	help
+	  Loading a device tree overlay dynamically can require the base
+	  device tree symbols to be present.
+	  If this is enabled, the device tree blobs will be bigger.
+
 config OF_OVERLAY
 	bool "Device Tree overlays"
 	select OF_DYNAMIC
 	select OF_FLATTREE
 	select OF_RESOLVE
+	select OF_SYMBOLS
 	help
 	  Overlays are a method to dynamically modify part of the kernel's
 	  device tree with dynamically loaded data.
diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib
index 79be57fdd32a..4c330e565297 100644
--- a/scripts/Makefile.lib
+++ b/scripts/Makefile.lib
@@ -319,8 +319,13 @@ endif
 
 DTC_FLAGS += $(DTC_FLAGS_$(basetarget))
 
-# Set -@ if the target is a base DTB that overlay is applied onto
-DTC_FLAGS += $(if $(filter $(patsubst $(obj)/%,%,$@), $(base-dtb-y)), -@)
+ifeq ($(CONFIG_OF_SYMBOLS),y)
+	# Add symbols in all devicetrees
+	DTC_FLAGS += -@
+else
+	# Set -@ if the target is a base DTB that overlay is applied onto
+	DTC_FLAGS += $(if $(filter $(patsubst $(obj)/%,%,$@), $(base-dtb-y)), -@)
+endif
 
 # Generate an assembly file to wrap the output of the device tree compiler
 quiet_cmd_dt_S_dtb= DTB     $@
-- 
2.36.0

[RFC PATCH v2 3/3] ARM: dto: Add bcm2711-rpi-7-inches-ts.dts overlay

[Detlev Casanova]

Add a device tree overlay to support the official Raspberrypi 7" touchscreen for
the bcm2711 devices.

The panel is connected on the DSI 1 port and uses the simple-panel
driver.

The device tree also makes sure to activate the pixelvalve[0-4] CRTC modules

Signed-off-by: Detlev Casanova <detlev.casanova@collabora.com>
---
 arch/arm/boot/dts/Makefile                    |   4 +
 arch/arm/boot/dts/overlays/Makefile           |   3 +
 .../dts/overlays/bcm2711-rpi-7-inches-ts.dts  | 125 ++++++++++++++++++
 arch/arm64/boot/dts/broadcom/Makefile         |   4 +
 .../arm64/boot/dts/broadcom/overlays/Makefile |   3 +
 .../overlays/bcm2711-rpi-7-inches-ts.dts      |   2 +
 6 files changed, 141 insertions(+)
 create mode 100644 arch/arm/boot/dts/overlays/Makefile
 create mode 100644 arch/arm/boot/dts/overlays/bcm2711-rpi-7-inches-ts.dts
 create mode 100644 arch/arm64/boot/dts/broadcom/overlays/Makefile
 create mode 100644 arch/arm64/boot/dts/broadcom/overlays/bcm2711-rpi-7-inches-ts.dts

diff --git a/arch/arm/boot/dts/Makefile b/arch/arm/boot/dts/Makefile
index 235ad559acb2..eb0b0b121947 100644
--- a/arch/arm/boot/dts/Makefile
+++ b/arch/arm/boot/dts/Makefile
@@ -1549,3 +1549,7 @@ dtb-$(CONFIG_ARCH_ASPEED) += \
 	aspeed-bmc-vegman-n110.dtb \
 	aspeed-bmc-vegman-rx20.dtb \
 	aspeed-bmc-vegman-sx20.dtb
+
+ifeq ($(CONFIG_OF_OVERLAY),y)
+subdir-y	+= overlays
+endif
diff --git a/arch/arm/boot/dts/overlays/Makefile b/arch/arm/boot/dts/overlays/Makefile
new file mode 100644
index 000000000000..c90883dfaf91
--- /dev/null
+++ b/arch/arm/boot/dts/overlays/Makefile
@@ -0,0 +1,3 @@
+# SPDX-License-Identifier: GPL-2.0
+
+dtb-$(CONFIG_ARCH_BCM2835) += bcm2711-rpi-7-inches-ts.dtbo
diff --git a/arch/arm/boot/dts/overlays/bcm2711-rpi-7-inches-ts.dts b/arch/arm/boot/dts/overlays/bcm2711-rpi-7-inches-ts.dts
new file mode 100644
index 000000000000..de98a6c1079a
--- /dev/null
+++ b/arch/arm/boot/dts/overlays/bcm2711-rpi-7-inches-ts.dts
@@ -0,0 +1,125 @@
+// SPDX-License-Identifier: GPL-2.0
+
+/dts-v1/;
+/plugin/;
+
+&{/} {
+	#address-cells = <2>;
+	#size-cells = <1>;
+
+	panel_disp1: panel@0 {
+		reg = <0 0 0>;
+		compatible = "raspberrypi,7inch-dsi", "simple-panel";
+		backlight = <&reg_display>;
+		power-supply = <&reg_display>;
+		status = "okay";
+
+		port {
+			panel_in: endpoint {
+				remote-endpoint = <&bridge_out>;
+			};
+		};
+	};
+
+	reg_bridge: regulator@0 {
+		reg = <0 0 0>;
+		compatible = "regulator-fixed";
+		regulator-name = "bridge_reg";
+		gpio = <&reg_display 0 0>;
+		vin-supply = <&reg_display>;
+		enable-active-high;
+		status = "okay";
+	};
+};
+
+&i2c_csi_dsi {
+	#address-cells = <1>;
+	#size-cells = <0>;
+
+	ft5406: touchscreen@38 {
+		compatible = "edt,edt-ft5506";
+		reg = <0x38>;
+		status = "okay";
+
+		vcc-supply = <&reg_display>;
+		reset-gpio = <&reg_display 1 1>;
+
+		touchscreen-size-x = < 800 >;
+		touchscreen-size-y = < 480 >;
+
+		touchscreen-inverted-x;
+		touchscreen-inverted-y;
+	};
+
+	reg_display: regulator@45 {
+		compatible = "raspberrypi,7inch-touchscreen-panel-regulator";
+		reg = <0x45>;
+		status = "okay";
+
+		gpio-controller;
+		#gpio-cells = <2>;
+	};
+
+};
+
+&dsi1 {
+	#address-cells = <1>;
+	#size-cells = <0>;
+
+	status = "okay";
+
+	port {
+		dsi_out: endpoint {
+			remote-endpoint = <&bridge_in>;
+		};
+	};
+
+	bridge@0 {
+		#address-cells = <1>;
+		#size-cells = <0>;
+
+		reg = <0>;
+		compatible = "toshiba,tc358762";
+
+		vddc-supply = <&reg_bridge>;
+
+		ports {
+			#address-cells = <1>;
+			#size-cells = <0>;
+
+			port@0 {
+				reg = <0>;
+				bridge_in: endpoint {
+					remote-endpoint = <&dsi_out>;
+				};
+			};
+
+			port@1 {
+				reg = <1>;
+				bridge_out: endpoint {
+					remote-endpoint = <&panel_in>;
+				};
+			};
+		};
+	};
+};
+
+&pixelvalve0 {
+	status = "okay";
+};
+
+&pixelvalve1 {
+	status = "okay";
+};
+
+&pixelvalve2 {
+	status = "okay";
+};
+
+&pixelvalve3 {
+	status = "okay";
+};
+
+&pixelvalve4 {
+	status = "okay";
+};
diff --git a/arch/arm64/boot/dts/broadcom/Makefile b/arch/arm64/boot/dts/broadcom/Makefile
index c6882032a428..a6c43c5b053a 100644
--- a/arch/arm64/boot/dts/broadcom/Makefile
+++ b/arch/arm64/boot/dts/broadcom/Makefile
@@ -7,6 +7,10 @@ dtb-$(CONFIG_ARCH_BCM2835) += bcm2711-rpi-400.dtb \
 			      bcm2837-rpi-3-b-plus.dtb \
 			      bcm2837-rpi-cm3-io3.dtb
 
+ifeq ($(CONFIG_OF_OVERLAY),y)
+subdir-y	+= overlays
+endif
+
 subdir-y	+= bcm4908
 subdir-y	+= northstar2
 subdir-y	+= stingray
diff --git a/arch/arm64/boot/dts/broadcom/overlays/Makefile b/arch/arm64/boot/dts/broadcom/overlays/Makefile
new file mode 100644
index 000000000000..c90883dfaf91
--- /dev/null
+++ b/arch/arm64/boot/dts/broadcom/overlays/Makefile
@@ -0,0 +1,3 @@
+# SPDX-License-Identifier: GPL-2.0
+
+dtb-$(CONFIG_ARCH_BCM2835) += bcm2711-rpi-7-inches-ts.dtbo
diff --git a/arch/arm64/boot/dts/broadcom/overlays/bcm2711-rpi-7-inches-ts.dts b/arch/arm64/boot/dts/broadcom/overlays/bcm2711-rpi-7-inches-ts.dts
new file mode 100644
index 000000000000..7d532b090305
--- /dev/null
+++ b/arch/arm64/boot/dts/broadcom/overlays/bcm2711-rpi-7-inches-ts.dts
@@ -0,0 +1,2 @@
+// SPDX-License-Identifier: GPL-2.0
+#include "arm/overlays/bcm2711-rpi-7-inches-ts.dts"
-- 
2.36.0

Re: [RFC PATCH v2 3/3] ARM: dto: Add bcm2711-rpi-7-inches-ts.dts overlay

[Rob Herring]

On Wed, Apr 27, 2022 at 02:52:43PM -0400, Detlev Casanova wrote:
> Add a device tree overlay to support the official Raspberrypi 7" touchscreen for
> the bcm2711 devices.
> 
> The panel is connected on the DSI 1 port and uses the simple-panel
> driver.
> 
> The device tree also makes sure to activate the pixelvalve[0-4] CRTC modules
> 
> Signed-off-by: Detlev Casanova <detlev.casanova@collabora.com>
> ---
>  arch/arm/boot/dts/Makefile                    |   4 +
>  arch/arm/boot/dts/overlays/Makefile           |   3 +
>  .../dts/overlays/bcm2711-rpi-7-inches-ts.dts  | 125 ++++++++++++++++++

.dtso is preferred. I think... It was discussed, but I never got an 
updated patch to switch.

>  arch/arm64/boot/dts/broadcom/Makefile         |   4 +
>  .../arm64/boot/dts/broadcom/overlays/Makefile |   3 +
>  .../overlays/bcm2711-rpi-7-inches-ts.dts      |   2 +
>  6 files changed, 141 insertions(+)
>  create mode 100644 arch/arm/boot/dts/overlays/Makefile
>  create mode 100644 arch/arm/boot/dts/overlays/bcm2711-rpi-7-inches-ts.dts

A global (to arm) 'overlays' directory will create the same mess that we 
have in arch/arm/boot/dts/. IMO, first you should move all the Broadcom 
dts files to a 'broadcom' subdirectory like we have for arm64.

>  create mode 100644 arch/arm64/boot/dts/broadcom/overlays/Makefile
>  create mode 100644 arch/arm64/boot/dts/broadcom/overlays/bcm2711-rpi-7-inches-ts.dts
> 
> diff --git a/arch/arm/boot/dts/Makefile b/arch/arm/boot/dts/Makefile
> index 235ad559acb2..eb0b0b121947 100644
> --- a/arch/arm/boot/dts/Makefile
> +++ b/arch/arm/boot/dts/Makefile
> @@ -1549,3 +1549,7 @@ dtb-$(CONFIG_ARCH_ASPEED) += \
>  	aspeed-bmc-vegman-n110.dtb \
>  	aspeed-bmc-vegman-rx20.dtb \
>  	aspeed-bmc-vegman-sx20.dtb
> +
> +ifeq ($(CONFIG_OF_OVERLAY),y)
> +subdir-y	+= overlays

I don't think this should depend on the config. If it does, you can do 
this in scripts/Makefile.lib by removing .dtbo targets. Or this could 
have been just:

subdir-$(CONFIG_OF_OVERLAY) += overlays

But I prefer the former so each platform is not picking their own way.

> +endif
> diff --git a/arch/arm/boot/dts/overlays/Makefile b/arch/arm/boot/dts/overlays/Makefile
> new file mode 100644
> index 000000000000..c90883dfaf91
> --- /dev/null
> +++ b/arch/arm/boot/dts/overlays/Makefile
> @@ -0,0 +1,3 @@
> +# SPDX-License-Identifier: GPL-2.0
> +
> +dtb-$(CONFIG_ARCH_BCM2835) += bcm2711-rpi-7-inches-ts.dtbo

The overlays should be applied to the base dtb(s) to ensure they 
actually apply and so we can validate them with schema. kbuild supports 
this already.


> diff --git a/arch/arm/boot/dts/overlays/bcm2711-rpi-7-inches-ts.dts 
> b/arch/arm/boot/dts/overlays/bcm2711-rpi-7-inches-ts.dts
> new file mode 100644
> index 000000000000..de98a6c1079a
> --- /dev/null
> +++ b/arch/arm/boot/dts/overlays/bcm2711-rpi-7-inches-ts.dts
> @@ -0,0 +1,125 @@
> +// SPDX-License-Identifier: GPL-2.0

No one uses RPi with *BSD? Dual licensing is preferred. Of course, what 
this applies to should have similar licensing.

> +
> +/dts-v1/;
> +/plugin/;
> +
> +&{/} {
> +	#address-cells = <2>;
> +	#size-cells = <1>;
> +
> +	panel_disp1: panel@0 {

What is '0' representing?

> +		reg = <0 0 0>;
> +		compatible = "raspberrypi,7inch-dsi", "simple-panel";
> +		backlight = <&reg_display>;
> +		power-supply = <&reg_display>;
> +		status = "okay";

That's the default. Same thing in a few other spots.

> +
> +		port {
> +			panel_in: endpoint {
> +				remote-endpoint = <&bridge_out>;
> +			};
> +		};
> +	};
> +
> +	reg_bridge: regulator@0 {

Oops! 2 different things at the same address!

> +		reg = <0 0 0>;

'regulator-fixed' doesn't have an address.

> +		compatible = "regulator-fixed";
> +		regulator-name = "bridge_reg";
> +		gpio = <&reg_display 0 0>;
> +		vin-supply = <&reg_display>;
> +		enable-active-high;
> +		status = "okay";
> +	};
> +};
> +
> +&i2c_csi_dsi {
> +	#address-cells = <1>;
> +	#size-cells = <0>;
> +
> +	ft5406: touchscreen@38 {
> +		compatible = "edt,edt-ft5506";
> +		reg = <0x38>;
> +		status = "okay";
> +
> +		vcc-supply = <&reg_display>;
> +		reset-gpio = <&reg_display 1 1>;
> +
> +		touchscreen-size-x = < 800 >;
> +		touchscreen-size-y = < 480 >;
> +
> +		touchscreen-inverted-x;
> +		touchscreen-inverted-y;
> +	};
> +
> +	reg_display: regulator@45 {
> +		compatible = "raspberrypi,7inch-touchscreen-panel-regulator";
> +		reg = <0x45>;
> +		status = "okay";
> +
> +		gpio-controller;
> +		#gpio-cells = <2>;

The regulator is a gpio-controller?

> +	};
> +
> +};
> +
> +&dsi1 {
> +	#address-cells = <1>;
> +	#size-cells = <0>;
> +
> +	status = "okay";
> +
> +	port {
> +		dsi_out: endpoint {
> +			remote-endpoint = <&bridge_in>;
> +		};
> +	};
> +
> +	bridge@0 {

> +		#address-cells = <1>;
> +		#size-cells = <0>;

Not valid here. But I shouldn't have to tell you this as the schema 
checks will. Please run them. Applied to a base should work for sure. As 
just a .dtbo, there's probably some issues, but complete nodes like this 
should validate fine.

> +
> +		reg = <0>;
> +		compatible = "toshiba,tc358762";
> +
> +		vddc-supply = <&reg_bridge>;
> +
> +		ports {
> +			#address-cells = <1>;
> +			#size-cells = <0>;
> +
> +			port@0 {
> +				reg = <0>;
> +				bridge_in: endpoint {
> +					remote-endpoint = <&dsi_out>;
> +				};
> +			};
> +
> +			port@1 {
> +				reg = <1>;
> +				bridge_out: endpoint {
> +					remote-endpoint = <&panel_in>;
> +				};
> +			};
> +		};
> +	};
> +};
> +
> +&pixelvalve0 {
> +	status = "okay";
> +};
> +
> +&pixelvalve1 {
> +	status = "okay";
> +};
> +
> +&pixelvalve2 {
> +	status = "okay";
> +};
> +
> +&pixelvalve3 {
> +	status = "okay";
> +};
> +
> +&pixelvalve4 {
> +	status = "okay";
> +};

Re: [RFC PATCH v2 2/3] of: Add support for -@ when compiling overlays

[Rob Herring]

On Wed, Apr 27, 2022 at 02:52:42PM -0400, Detlev Casanova wrote:
> This commit adds an option to compile all device trees with -@ to add the
> symbol table to the Device Tree Blobs.

Why would we want to tie this to the kernel config?

Globally enabling it has already been discussed and rejected.

> It prepares the introduction of device tree overlays that are
> not applied on device trees at compile time (dtbo files.)
> 
> These device tree overlays will be used by either a bootloader or a
> linux userspace tool to extend the base device tree.
> 
> This is used e.g. for drivers that need device tree nodes for optional
> non plug and play devices, like an external DSI touchscreen panel that
> embeds different i2c devices to control it.

You can already set DTC_FLAGS per directory (and target?), so enable it 
for the dtbs that have overlays.

> 
> Signed-off-by: Detlev Casanova <detlev.casanova@collabora.com>
> ---
>  drivers/of/Kconfig   | 8 ++++++++
>  scripts/Makefile.lib | 9 +++++++--
>  2 files changed, 15 insertions(+), 2 deletions(-)

Re: [RFC PATCH v2 2/3] of: Add support for -@ when compiling overlays

[Florian Fainelli]

On 4/27/2022 2:24 PM, Rob Herring wrote:
> On Wed, Apr 27, 2022 at 02:52:42PM -0400, Detlev Casanova wrote:
>> This commit adds an option to compile all device trees with -@ to add the
>> symbol table to the Device Tree Blobs.
> 
> Why would we want to tie this to the kernel config?
> 
> Globally enabling it has already been discussed and rejected.
> 
>> It prepares the introduction of device tree overlays that are
>> not applied on device trees at compile time (dtbo files.)
>>
>> These device tree overlays will be used by either a bootloader or a
>> linux userspace tool to extend the base device tree.
>>
>> This is used e.g. for drivers that need device tree nodes for optional
>> non plug and play devices, like an external DSI touchscreen panel that
>> embeds different i2c devices to control it.
> 
> You can already set DTC_FLAGS per directory (and target?), so enable it
> for the dtbs that have overlays.

Looks like this patch series from Aurelien should take care of that:

https://lore.kernel.org/linux-arm-kernel/20220427233607.1225419-1-
aurelien@aurel32.net/
-- 
Florian

Re: [RFC PATCH v2 3/3] ARM: dto: Add bcm2711-rpi-7-inches-ts.dts overlay

[Geert Uytterhoeven]

Hi Rob,

On Wed, Apr 27, 2022 at 11:23 PM Rob Herring <robh@kernel.org> wrote:
> On Wed, Apr 27, 2022 at 02:52:43PM -0400, Detlev Casanova wrote:
> > Add a device tree overlay to support the official Raspberrypi 7" touchscreen for
> > the bcm2711 devices.
> >
> > The panel is connected on the DSI 1 port and uses the simple-panel
> > driver.
> >
> > The device tree also makes sure to activate the pixelvalve[0-4] CRTC modules
> >
> > Signed-off-by: Detlev Casanova <detlev.casanova@collabora.com>
> > ---
> >  arch/arm/boot/dts/Makefile                    |   4 +
> >  arch/arm/boot/dts/overlays/Makefile           |   3 +
> >  .../dts/overlays/bcm2711-rpi-7-inches-ts.dts  | 125 ++++++++++++++++++
>
> .dtso is preferred. I think... It was discussed, but I never got an
> updated patch to switch.

Unfortunately that switch indeed hasn't happened yet.
My main gripe with .dts for overlays is that you cannot know whether
it's an overlay or not without reading the file's contents.
Hence tools like make also cannot know, and you need to e.g. list
all files explicitly in a Makefile.

> >  arch/arm64/boot/dts/broadcom/Makefile         |   4 +
> >  .../arm64/boot/dts/broadcom/overlays/Makefile |   3 +
> >  .../overlays/bcm2711-rpi-7-inches-ts.dts      |   2 +
> >  6 files changed, 141 insertions(+)
> >  create mode 100644 arch/arm/boot/dts/overlays/Makefile
> >  create mode 100644 arch/arm/boot/dts/overlays/bcm2711-rpi-7-inches-ts.dts
>
> A global (to arm) 'overlays' directory will create the same mess that we
> have in arch/arm/boot/dts/. IMO, first you should move all the Broadcom
> dts files to a 'broadcom' subdirectory like we have for arm64.

As I believe this display is not only used with real Raspberry Pi
devices, it makes sense to not have it a broadcom directory.
In fact it may be used on other architectures than arm, too, so I
think we need an arch-agnostic directory for overlays[1]?
This may need remapping of labels. I'm aware the rpi infrastructure has
support for remapping labels when applying overlays during boot, but
AFAIK this is not yet supported by fdtoverlay (or perhaps by a fork?)?
Note that the remapping is also needed if you want to apply two
instances of the same overlay.

> >  create mode 100644 arch/arm64/boot/dts/broadcom/overlays/Makefile
> >  create mode 100644 arch/arm64/boot/dts/broadcom/overlays/bcm2711-rpi-7-inches-ts.dts

And this one just includes the former, and thus sort-of serves as an
example of my point above ;-)

[1] Note that this does not only apply to overlays: soon we will
    have a full SoC peripheral description in r9a07g043.dtsi to
    share between RZ/G2UL (arm64) and RZ/Five (riscv)).

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds

Re: [RFC PATCH v2 3/3] ARM: dto: Add bcm2711-rpi-7-inches-ts.dts overlay

[Rob Herring]

On Thu, Apr 28, 2022 at 08:44:17AM +0200, Geert Uytterhoeven wrote:
> Hi Rob,
> 
> On Wed, Apr 27, 2022 at 11:23 PM Rob Herring <robh@kernel.org> wrote:
> > On Wed, Apr 27, 2022 at 02:52:43PM -0400, Detlev Casanova wrote:
> > > Add a device tree overlay to support the official Raspberrypi 7" touchscreen for
> > > the bcm2711 devices.
> > >
> > > The panel is connected on the DSI 1 port and uses the simple-panel
> > > driver.
> > >
> > > The device tree also makes sure to activate the pixelvalve[0-4] CRTC modules
> > >
> > > Signed-off-by: Detlev Casanova <detlev.casanova@collabora.com>
> > > ---
> > >  arch/arm/boot/dts/Makefile                    |   4 +
> > >  arch/arm/boot/dts/overlays/Makefile           |   3 +
> > >  .../dts/overlays/bcm2711-rpi-7-inches-ts.dts  | 125 ++++++++++++++++++
> >
> > .dtso is preferred. I think... It was discussed, but I never got an
> > updated patch to switch.
> 
> Unfortunately that switch indeed hasn't happened yet.
> My main gripe with .dts for overlays is that you cannot know whether
> it's an overlay or not without reading the file's contents.
> Hence tools like make also cannot know, and you need to e.g. list
> all files explicitly in a Makefile.

See my reply in the other thread for that.

> > >  arch/arm64/boot/dts/broadcom/Makefile         |   4 +
> > >  .../arm64/boot/dts/broadcom/overlays/Makefile |   3 +
> > >  .../overlays/bcm2711-rpi-7-inches-ts.dts      |   2 +
> > >  6 files changed, 141 insertions(+)
> > >  create mode 100644 arch/arm/boot/dts/overlays/Makefile
> > >  create mode 100644 arch/arm/boot/dts/overlays/bcm2711-rpi-7-inches-ts.dts
> >
> > A global (to arm) 'overlays' directory will create the same mess that we
> > have in arch/arm/boot/dts/. IMO, first you should move all the Broadcom
> > dts files to a 'broadcom' subdirectory like we have for arm64.
> 
> As I believe this display is not only used with real Raspberry Pi
> devices, it makes sense to not have it a broadcom directory.

Then at a minimum 'bcm2711' in the name is not appropriate.

I'm doubtful that as-is the overlay would apply to boards outside of 
RPi's. For this to work (well), there needs to be a connector node to 
translate between connector resources and the base board resources. See 
the recent mikrobus thread[2].

> In fact it may be used on other architectures than arm, too, so I
> think we need an arch-agnostic directory for overlays[1]?

Probably so.

Personally, I would prefer no DTs under /arch.

> This may need remapping of labels. I'm aware the rpi infrastructure has
> support for remapping labels when applying overlays during boot, but
> AFAIK this is not yet supported by fdtoverlay (or perhaps by a fork?)?
> Note that the remapping is also needed if you want to apply two
> instances of the same overlay.

First I've heard of label remapping... I have a lot of concerns about 
using labels for overlays. For starters, with a flip of a switch (-@), 
they all become an ABI when they were not previously. I think at a 
minimum, we need an annotation so that a subset can be exported. 
Anything that's an ABI, we should be documenting and reviewing.

The requirement for overlays upstream is that they are applied at build 
time to a base DT. Otherwise, we can't validate them completely. So if 
there's a label remapping dependency on these, sounds like there is some 
more work to do. The first being getting agreement that label remapping 
is the right approach.

Common label names or some remapping for targets kind of works, but 
easily falls apart. For example, GPIO (or any provider with identifier 
cells) numbering or SPI CS numbering would be different. 

Rob

[2] https://lore.kernel.org/all/YmFo+EntwxIsco%2Ft@robh.at.kernel.org/

Re: [RFC PATCH v2 0/3] ARM: dts: Support official Raspberry Pi 7inch touchscreen

[Detlev Casanova]

On Monday, February 21, 2022 9:01:14 A.M. EDT Detlev Casanova wrote:
> Add a devicetree overlay to support the official Raspberry Pi 7inch
> touchscreen.
> 
> This also demuxes the i2c0 controller to support both pinctrls.
> 
> Changes in v2:
>  * The device tree in now an overlay
>  * The i2c demux patch is kept for now to have a working patch set. It has
>    not been merged yet in [1].
>  * The device tree overlay doesn't use fragments. It is working as is
>    but not enough literature was found to go one way or the other.
> 
> [1] https://www.spinics.net/lists/arm-kernel/msg944330.html
> 
> Detlev Casanova (3):
>   ARM: dts: bcm2*: Demux i2c0 with a pinctrl
>   of: Add support for -@ when compiling overlays
>   ARM: dto: Add bcm2711-rpi-7-inches-ts.dts overlay
> 
>  arch/arm/boot/dts/Makefile                    |   4 +
>  arch/arm/boot/dts/bcm2711-rpi-4-b.dts         |   1 +
>  arch/arm/boot/dts/bcm2711.dtsi                |   2 +-
>  arch/arm/boot/dts/bcm2835-rpi.dtsi            |   9 +-
>  .../boot/dts/bcm283x-rpi-i2c0mux_0_44.dtsi    |   4 +
>  arch/arm/boot/dts/bcm283x.dtsi                |  26 +++-
>  arch/arm/boot/dts/overlays/Makefile           |   3 +
>  .../dts/overlays/bcm2711-rpi-7-inches-ts.dts  | 125 ++++++++++++++++++
>  arch/arm64/boot/dts/broadcom/Makefile         |   4 +
>  .../arm64/boot/dts/broadcom/overlays/Makefile |   3 +
>  .../overlays/bcm2711-rpi-7-inches-ts.dts      |   2 +
>  drivers/of/Kconfig                            |   8 ++
>  scripts/Makefile.lib                          |   9 +-
>  13 files changed, 193 insertions(+), 7 deletions(-)
>  create mode 100644 arch/arm/boot/dts/bcm283x-rpi-i2c0mux_0_44.dtsi
>  create mode 100644 arch/arm/boot/dts/overlays/Makefile
>  create mode 100644 arch/arm/boot/dts/overlays/bcm2711-rpi-7-inches-ts.dts
>  create mode 100644 arch/arm64/boot/dts/broadcom/overlays/Makefile
>  create mode 100644
> arch/arm64/boot/dts/broadcom/overlays/bcm2711-rpi-7-inches-ts.dts

Hello,

Any comments on this ?

Regards,

Detlev.

[RFC PATCH v2 0/3] ARM: dts: Support official Raspberry Pi 7inch touchscreen

[Detlev Casanova]

Add a devicetree overlay to support the official Raspberry Pi 7inch touchscreen.

This also demuxes the i2c0 controller to support both pinctrls.

Changes in v2:
 * The device tree in now an overlay
 * The i2c demux patch is kept for now to have a working patch set. It has
   not been merged yet in [1].
 * The device tree overlay doesn't use fragments. It is working as is 
   but not enough literature was found to go one way or the other.

[1] https://www.spinics.net/lists/arm-kernel/msg944330.html

Detlev Casanova (3):
  ARM: dts: bcm2*: Demux i2c0 with a pinctrl
  of: Add support for -@ when compiling overlays
  ARM: dto: Add bcm2711-rpi-7-inches-ts.dts overlay

 arch/arm/boot/dts/Makefile                    |   4 +
 arch/arm/boot/dts/bcm2711-rpi-4-b.dts         |   1 +
 arch/arm/boot/dts/bcm2711.dtsi                |   2 +-
 arch/arm/boot/dts/bcm2835-rpi.dtsi            |   9 +-
 .../boot/dts/bcm283x-rpi-i2c0mux_0_44.dtsi    |   4 +
 arch/arm/boot/dts/bcm283x.dtsi                |  26 +++-
 arch/arm/boot/dts/overlays/Makefile           |   3 +
 .../dts/overlays/bcm2711-rpi-7-inches-ts.dts  | 125 ++++++++++++++++++
 arch/arm64/boot/dts/broadcom/Makefile         |   4 +
 .../arm64/boot/dts/broadcom/overlays/Makefile |   3 +
 .../overlays/bcm2711-rpi-7-inches-ts.dts      |   2 +
 drivers/of/Kconfig                            |   8 ++
 scripts/Makefile.lib                          |   9 +-
 13 files changed, 193 insertions(+), 7 deletions(-)
 create mode 100644 arch/arm/boot/dts/bcm283x-rpi-i2c0mux_0_44.dtsi
 create mode 100644 arch/arm/boot/dts/overlays/Makefile
 create mode 100644 arch/arm/boot/dts/overlays/bcm2711-rpi-7-inches-ts.dts
 create mode 100644 arch/arm64/boot/dts/broadcom/overlays/Makefile
 create mode 100644 arch/arm64/boot/dts/broadcom/overlays/bcm2711-rpi-7-inches-ts.dts

-- 
2.35.1