[PATCH v2 0/5] Add remaining IO expansions on Lichee Pi 4A

[PATCH v2 0/5] Add remaining IO expansions on Lichee Pi 4A

[Icenowy Zheng]

This patchset is split off the "Add TH1520 USB support" patchset,
dedicating to enable the IO expansion chips, because the situation
becomes complex when one of them (but not all) was added for Wi-Fi
support.

I fixed a small issue of the existing I2C1 device node, and then all
original patches are aligned with the existing I2C1 node for
consistency.

Emil Renner Berthing (2):
  riscv: dts: thead: Add IO labels for the IO expansion on I2C1
  riscv: dts: thead: Add remaining Lichee Pi 4A IO expansions

Icenowy Zheng (2):
  riscv: dts: thead: th1520: remove pclk for I2C1
  riscv: dts: thead: lpi4a: sort nodes

Thomas Bonnefille (1):
  riscv: dts: thead: Add TH1520 I2C nodes

 .../boot/dts/thead/th1520-lichee-pi-4a.dts    | 141 +++++++++++++-----
 arch/riscv/boot/dts/thead/th1520.dtsi         |  53 ++++++-
 2 files changed, 157 insertions(+), 37 deletions(-)

-- 
2.52.0

[PATCH v2 1/5] riscv: dts: thead: th1520: remove pclk for I2C1

[Icenowy Zheng]

The I2C1 node added previously to the th1520.dtsi file has two clocks
set -- one "ref" clock (CLK_I2C1) and one "pclk" (CLK_PERI_APB_PCLK).

However, the CLK_I2C1 clock is just a clock gate with the
CLK_PERI_APB_PCLK clock as its input. In addition, when it's gated,
reading registers from the I2C controller returns fixed value (the last
read value) for all registers. These facts indicate that the CLK_I2C1
clock is the true APB clock fed into the I2C controller instead of a
dedicated reference clock.

Leave only the CLK_I2C1 clock as the `clocks` property of the I2C1
device node and remove `clock-names` property, which represents the I2C
controller only takes a single clock both as the APB clock and the
reference clock.

Fixes: 2f60e3516330 ("riscv: dts: thead: Add TH1520 I2C1 controller")
Signed-off-by: Icenowy Zheng <zhengxingda@iscas.ac.cn>
---
 arch/riscv/boot/dts/thead/th1520.dtsi | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/arch/riscv/boot/dts/thead/th1520.dtsi b/arch/riscv/boot/dts/thead/th1520.dtsi
index 94932c51b7e39..db23624696b73 100644
--- a/arch/riscv/boot/dts/thead/th1520.dtsi
+++ b/arch/riscv/boot/dts/thead/th1520.dtsi
@@ -415,8 +415,7 @@ i2c1: i2c@ffe7f24000 {
 			compatible = "thead,th1520-i2c", "snps,designware-i2c";
 			reg = <0xff 0xe7f24000 0x0 0x4000>;
 			interrupts = <45 IRQ_TYPE_LEVEL_HIGH>;
-			clocks = <&clk CLK_I2C1>, <&clk CLK_PERI_APB_PCLK>;
-			clock-names = "ref", "pclk";
+			clocks = <&clk CLK_I2C1>;
 			#address-cells = <1>;
 			#size-cells = <0>;
 			status = "disabled";
-- 
2.52.0

[PATCH v2 2/5] riscv: dts: thead: Add TH1520 I2C nodes

[Icenowy Zheng]

From: Thomas Bonnefille <thomas.bonnefille@bootlin.com>

Add nodes for the remaining five I2C controllers on the T-Head TH1520
RISCV SoC.

Signed-off-by: Thomas Bonnefille <thomas.bonnefille@bootlin.com>
Reviewed-by: Drew Fustini <dfustini@tenstorrent.com>
[Icenowy: rebase and reword commit message to exclude I2C1]
Signed-off-by: Icenowy Zheng <zhengxingda@iscas.ac.cn>
---
 arch/riscv/boot/dts/thead/th1520.dtsi | 50 +++++++++++++++++++++++++++
 1 file changed, 50 insertions(+)

diff --git a/arch/riscv/boot/dts/thead/th1520.dtsi b/arch/riscv/boot/dts/thead/th1520.dtsi
index db23624696b73..b01a94785d870 100644
--- a/arch/riscv/boot/dts/thead/th1520.dtsi
+++ b/arch/riscv/boot/dts/thead/th1520.dtsi
@@ -411,6 +411,16 @@ uart3: serial@ffe7f04000 {
 			status = "disabled";
 		};
 
+		i2c0: i2c@ffe7f20000 {
+			compatible = "thead,th1520-i2c", "snps,designware-i2c";
+			reg = <0xff 0xe7f20000 0x0 0x4000>;
+			interrupts = <44 IRQ_TYPE_LEVEL_HIGH>;
+			clocks = <&clk CLK_I2C0>;
+			#address-cells = <1>;
+			#size-cells = <0>;
+			status = "disabled";
+		};
+
 		i2c1: i2c@ffe7f24000 {
 			compatible = "thead,th1520-i2c", "snps,designware-i2c";
 			reg = <0xff 0xe7f24000 0x0 0x4000>;
@@ -421,6 +431,16 @@ i2c1: i2c@ffe7f24000 {
 			status = "disabled";
 		};
 
+		i2c4: i2c@ffe7f28000 {
+			compatible = "thead,th1520-i2c", "snps,designware-i2c";
+			reg = <0xff 0xe7f28000 0x0 0x4000>;
+			interrupts = <48 IRQ_TYPE_LEVEL_HIGH>;
+			clocks = <&clk CLK_I2C4>;
+			#address-cells = <1>;
+			#size-cells = <0>;
+			status = "disabled";
+		};
+
 		gpio@ffe7f34000 {
 			compatible = "snps,dw-apb-gpio";
 			reg = <0xff 0xe7f34000 0x0 0x1000>;
@@ -519,6 +539,16 @@ padctrl0_apsys: pinctrl@ffec007000 {
 			thead,pad-group = <3>;
 		};
 
+		i2c2: i2c@ffec00c000 {
+			compatible = "thead,th1520-i2c", "snps,designware-i2c";
+			reg = <0xff 0xec00c000 0x0 0x4000>;
+			interrupts = <46 IRQ_TYPE_LEVEL_HIGH>;
+			clocks = <&clk CLK_I2C2>;
+			#address-cells = <1>;
+			#size-cells = <0>;
+			status = "disabled";
+		};
+
 		uart2: serial@ffec010000 {
 			compatible = "snps,dw-apb-uart";
 			reg = <0xff 0xec010000 0x0 0x4000>;
@@ -530,6 +560,16 @@ uart2: serial@ffec010000 {
 			status = "disabled";
 		};
 
+		i2c3: i2c@ffec014000 {
+			compatible = "thead,th1520-i2c", "snps,designware-i2c";
+			reg = <0xff 0xec014000 0x0 0x4000>;
+			interrupts = <47 IRQ_TYPE_LEVEL_HIGH>;
+			clocks = <&clk CLK_I2C3>;
+			#address-cells = <1>;
+			#size-cells = <0>;
+			status = "disabled";
+		};
+
 		pwm: pwm@ffec01c000 {
 			compatible = "thead,th1520-pwm";
 			reg = <0xff 0xec01c000 0x0 0x4000>;
@@ -735,6 +775,16 @@ uart5: serial@fff7f0c000 {
 			status = "disabled";
 		};
 
+		i2c5: i2c@fff7f2c000 {
+			compatible = "thead,th1520-i2c", "snps,designware-i2c";
+			reg = <0xff 0xf7f2c000 0x0 0x4000>;
+			interrupts = <49 IRQ_TYPE_LEVEL_HIGH>;
+			clocks = <&clk CLK_I2C5>;
+			#address-cells = <1>;
+			#size-cells = <0>;
+			status = "disabled";
+		};
+
 		timer4: timer@ffffc33000 {
 			compatible = "snps,dw-apb-timer";
 			reg = <0xff 0xffc33000 0x0 0x14>;
-- 
2.52.0

[PATCH v2 3/5] riscv: dts: thead: lpi4a: sort nodes

[Icenowy Zheng]

Although "D", "H" and "I" are earlier in the alphabet than "P", the DPU,
HDMI and I2C1 nodes were added after PADCTRL nodes in the Lichee Pi 4A
device tree; in addition the PADCTRL1 node is placed before the
PADCTRL0 one.

Sort the nodes in this device tree.

Signed-off-by: Icenowy Zheng <zhengxingda@iscas.ac.cn>
---
 .../boot/dts/thead/th1520-lichee-pi-4a.dts    | 72 +++++++++----------
 1 file changed, 36 insertions(+), 36 deletions(-)

diff --git a/arch/riscv/boot/dts/thead/th1520-lichee-pi-4a.dts b/arch/riscv/boot/dts/thead/th1520-lichee-pi-4a.dts
index af6f25ebbf607..74b120c6b063a 100644
--- a/arch/riscv/boot/dts/thead/th1520-lichee-pi-4a.dts
+++ b/arch/riscv/boot/dts/thead/th1520-lichee-pi-4a.dts
@@ -103,17 +103,31 @@ fan: pwm-fan {
 
 };
 
-&padctrl1_apsys {
-	i2c1_pins: i2c1-0 {
-		i2c-pins {
-			pins = "I2C1_SCL", "I2C1_SDA";
-			function = "i2c";
-			bias-pull-up = <2100>;
-			drive-strength = <7>;
-			input-enable;
-			input-schmitt-enable;
-			slew-rate = <0>;
-		};
+&dpu {
+	status = "okay";
+};
+
+&hdmi {
+	status = "okay";
+};
+
+&hdmi_out_port {
+	hdmi_out_con: endpoint {
+		remote-endpoint = <&hdmi_con_in>;
+	};
+};
+
+&i2c1 {
+	clock-frequency = <400000>;
+	pinctrl-names = "default";
+	pinctrl-0 = <&i2c1_pins>;
+	status = "okay";
+
+	ioexp2: gpio@18 {
+		compatible = "nxp,pca9557";
+		reg = <0x18>;
+		gpio-controller;
+		#gpio-cells = <2>;
 	};
 };
 
@@ -153,17 +167,17 @@ rx-pins {
 	};
 };
 
-&i2c1 {
-	clock-frequency = <400000>;
-	pinctrl-names = "default";
-	pinctrl-0 = <&i2c1_pins>;
-	status = "okay";
-
-	ioexp2: gpio@18 {
-		compatible = "nxp,pca9557";
-		reg = <0x18>;
-		gpio-controller;
-		#gpio-cells = <2>;
+&padctrl1_apsys {
+	i2c1_pins: i2c1-0 {
+		i2c-pins {
+			pins = "I2C1_SCL", "I2C1_SDA";
+			function = "i2c";
+			bias-pull-up = <2100>;
+			drive-strength = <7>;
+			input-enable;
+			input-schmitt-enable;
+			slew-rate = <0>;
+		};
 	};
 };
 
@@ -179,20 +193,6 @@ &sdio1 {
 	status = "okay";
 };
 
-&dpu {
-	status = "okay";
-};
-
-&hdmi {
-	status = "okay";
-};
-
-&hdmi_out_port {
-	hdmi_out_con: endpoint {
-		remote-endpoint = <&hdmi_con_in>;
-	};
-};
-
 &uart0 {
 	pinctrl-names = "default";
 	pinctrl-0 = <&uart0_pins>;
-- 
2.52.0

[PATCH v2 4/5] riscv: dts: thead: Add IO labels for the IO expansion on I2C1

[Icenowy Zheng]

From: Emil Renner Berthing <emil.renner.berthing@canonical.com>

Add labels for GPIOs on the IO expansion chip on the I2C1 bus.

Signed-off-by: Emil Renner Berthing <emil.renner.berthing@canonical.com>
[Icenowy: Splitted off the patch adding all 3 IO expansions]
Signed-off-by: Icenowy Zheng <zhengxingda@iscas.ac.cn>
---
 arch/riscv/boot/dts/thead/th1520-lichee-pi-4a.dts | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/arch/riscv/boot/dts/thead/th1520-lichee-pi-4a.dts b/arch/riscv/boot/dts/thead/th1520-lichee-pi-4a.dts
index 74b120c6b063a..78f5979a56c14 100644
--- a/arch/riscv/boot/dts/thead/th1520-lichee-pi-4a.dts
+++ b/arch/riscv/boot/dts/thead/th1520-lichee-pi-4a.dts
@@ -128,6 +128,14 @@ ioexp2: gpio@18 {
 		reg = <0x18>;
 		gpio-controller;
 		#gpio-cells = <2>;
+		gpio-line-names = "",
+				  "cam0_reset",
+				  "cam1_reset",
+				  "cam2_reset",
+				  "wl_host_wake",
+				  "bt_resetn",
+				  "",
+				  "bt_host_wake";
 	};
 };
 
-- 
2.52.0

Re: [PATCH v2 4/5] riscv: dts: thead: Add IO labels for the IO expansion on I2C1

[sashiko-bot]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [Low] The `gpio-line-names` array added for `ioexp2` incorrectly labels pin 4 as `wl_host_wake` and pin 7 as `bt_host_wake`. This is physically and logically incorrect because the PCA9557 IO expander lacks interrupt output capability, meaning it cannot be used to receive asynchronous wake signals from peripherals to wake the host. Furthermore, pin 4 is already configured in the base device tree as a `reset-gpios` output for the `wifi_pwrseq` node, directly contradicting the input nature of a host wake signal.
--

--- Patch [4]: [PATCH v2 4/5] riscv: dts: thead: Add IO labels for the IO expansion on I2C1 ---
commit 0fffc115b12752f1a08b3dcb530cafc2d17759f7
Author: Emil Renner Berthing <emil.renner.berthing@canonical.com>

riscv: dts: thead: Add IO labels for the IO expansion on I2C1

This commit adds labels for GPIOs on the IO expansion chip on the I2C1 bus.

> diff --git a/arch/riscv/boot/dts/thead/th1520-lichee-pi-4a.dts b/arch/riscv/boot/dts/thead/th1520-lichee-pi-4a.dts
> index 74b120c6b063a..78f5979a56c14 100644
> --- a/arch/riscv/boot/dts/thead/th1520-lichee-pi-4a.dts
> +++ b/arch/riscv/boot/dts/thead/th1520-lichee-pi-4a.dts
> @@ -128,6 +128,14 @@ ioexp2: gpio@18 {
>  		reg = <0x18>;
>  		gpio-controller;
>  		#gpio-cells = <2>;
> +		gpio-line-names = "",
> +				  "cam0_reset",
> +				  "cam1_reset",
> +				  "cam2_reset",
> +				  "wl_host_wake",
> +				  "bt_resetn",
> +				  "",
> +				  "bt_host_wake";

[Severity: Low]
The PCA9557 IO expander lacks interrupt output capability, meaning it cannot
receive asynchronous wake signals from peripherals to wake the host.

Additionally, pin 4 is already configured as a reset output in the base
device tree for the wifi_pwrseq node:

arch/riscv/boot/dts/thead/th1520-lichee-pi-4a.dts:
	wifi_pwrseq: wifi-pwrseq {
		...
		reset-gpios = <&ioexp2 4 GPIO_ACTIVE_LOW>;
	};

This configuration contradicts the input nature of a host wake signal.

Are the labels wl_host_wake and bt_host_wake correct for this IO expander?

>  	};
>  };

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260714074515.1959352-1-zhengxingda@iscas.ac.cn?part=4

[PATCH v2 5/5] riscv: dts: thead: Add remaining Lichee Pi 4A IO expansions

[Icenowy Zheng]

From: Emil Renner Berthing <emil.renner.berthing@canonical.com>

Lichee Pi 4A has 3 I2C IO expansion chips onboard, connected to the
I2C0/1/3 busses. The I2C1 one is already added to the device tree, but
the I2C0/3 ones are not yet added.

Add device tree nodes for them.

Signed-off-by: Emil Renner Berthing <emil.renner.berthing@canonical.com>
[Icenowy: added commit description, enable SoC pull-up, remove I2C1 and
 aliases]
Signed-off-by: Icenowy Zheng <zhengxingda@iscas.ac.cn>
---
 .../boot/dts/thead/th1520-lichee-pi-4a.dts    | 63 +++++++++++++++++++
 1 file changed, 63 insertions(+)

diff --git a/arch/riscv/boot/dts/thead/th1520-lichee-pi-4a.dts b/arch/riscv/boot/dts/thead/th1520-lichee-pi-4a.dts
index 78f5979a56c14..75396cafb39dc 100644
--- a/arch/riscv/boot/dts/thead/th1520-lichee-pi-4a.dts
+++ b/arch/riscv/boot/dts/thead/th1520-lichee-pi-4a.dts
@@ -117,6 +117,23 @@ hdmi_out_con: endpoint {
 	};
 };
 
+&i2c0 {
+	clock-frequency = <400000>;
+	pinctrl-names = "default";
+	pinctrl-0 = <&i2c0_pins>;
+	status = "okay";
+
+	ioexp1: gpio@18 {
+		compatible = "nxp,pca9557";
+		reg = <0x18>;
+		gpio-controller;
+		#gpio-cells = <2>;
+		gpio-line-names = "cam0_dvdd12",
+				  "cam0_avdd28",
+				  "cam0_dovdd18";
+	};
+};
+
 &i2c1 {
 	clock-frequency = <400000>;
 	pinctrl-names = "default";
@@ -139,6 +156,28 @@ ioexp2: gpio@18 {
 	};
 };
 
+&i2c3 {
+	clock-frequency = <400000>;
+	pinctrl-names = "default";
+	pinctrl-0 = <&i2c3_pins>;
+	status = "okay";
+
+	ioexp3: gpio@18 {
+		compatible = "nxp,pca9557";
+		reg = <0x18>;
+		gpio-controller;
+		#gpio-cells = <2>;
+		gpio-line-names = "tp0_rst",
+				  "",
+				  "",
+				  "vcc5v_usb",
+				  "vdd28_tp0",
+				  "vdd33_lcd0",
+				  "vdd18_lcd0",
+				  "lcd0_reset";
+	};
+};
+
 &padctrl0_apsys {
 	fan_pins: fan-0 {
 		pwm1-pins {
@@ -152,6 +191,18 @@ pwm1-pins {
 		};
 	};
 
+	i2c3_pins: i2c3-0 {
+		i2c-pins {
+			pins = "I2C3_SCL", "I2C3_SDA";
+			function = "i2c";
+			bias-pull-up = <2100>;
+			drive-strength = <7>;
+			input-enable;
+			input-schmitt-enable;
+			slew-rate = <0>;
+		};
+	};
+
 	uart0_pins: uart0-0 {
 		tx-pins {
 			pins = "UART0_TXD";
@@ -176,6 +227,18 @@ rx-pins {
 };
 
 &padctrl1_apsys {
+	i2c0_pins: i2c0-0 {
+		i2c-pins {
+			pins = "I2C0_SCL", "I2C0_SDA";
+			function = "i2c";
+			bias-pull-up = <2100>;
+			drive-strength = <7>;
+			input-enable;
+			input-schmitt-enable;
+			slew-rate = <0>;
+		};
+	};
+
 	i2c1_pins: i2c1-0 {
 		i2c-pins {
 			pins = "I2C1_SCL", "I2C1_SDA";
-- 
2.52.0