drivers: input: add support for Renesas CTSU

boards/renesas/ek_ra2a1/Kconfig.defconfig

@@ -0,0 +1,9 @@
+# Copyright (c) 2025 Renesas Electronics Corporation
+# SPDX-License-Identifier: Apache-2.0
+
+if !INPUT_RENESAS_RA_QE_TOUCH_CFG
+
+config INPUT_RENESAS_RA_CTSU_NUM_SELF_ELEMENTS
+	default 1
+
+endif # INPUT_RENESAS_RA_QE_TOUCH_CFG

boards/renesas/ek_ra2a1/ek_ra2a1-pinctrl.dtsi

@@ -51,4 +51,12 @@
 			renesas,analog-enable;
 		};
 	};
+
+	ctsu_default: ctsu_default {
+		group1 {
+			/* TS01 TSCAP */
+			psels = <RA_PSEL(RA_PSEL_CTSU, 0, 1)>,
+				<RA_PSEL(RA_PSEL_CTSU, 4, 9)>;
+		};
+	};
 };

boards/renesas/ek_ra2a1/ek_ra2a1.dts

@@ -83,6 +83,10 @@
 	status = "okay";
 };
 
+&ioport4 {
+	status = "okay";
+};
+
 &port_irq6 {
 	interrupts = <29 3>;
 	status = "okay";
@@ -120,3 +124,40 @@
 &wdt {
 	status = "okay";
 };
+
+&ctsu {
+	pinctrl-0 = <&ctsu_default>;
+	pinctrl-names = "default";
+	interrupts = <10 3>, <11 3>, <12 3>;
+	interrupt-names = "ctsuwr", "ctsurd", "ctsufn";
+	clock-div = <1>;
+	pwr-supply-sel = "vcc";
+	atune1 = "normal";
+	measure-mode = "self-multi-scan";
+	tscap-gpios = <&ioport4 9 0>;
+	status = "okay";
+
+	group1 {
+		ctsuchac = <0x00>, <0x80>, <0x00>, <0x00>, <0x00>;
+		ctsuchtrc = <0x00>, <0x00>, <0x00>, <0x00>, <0x00>;
+		rx-count = <1>;
+		tx-count = <0>;
+		ssdiv = "1.00";
+		so = <0x108>;
+		snum = <0x01>;
+		sdpa = <0x0B>;
+		on-freq = <3>;
+		off-freq = <3>;
+		drift-freq = <255>;
+		cancel-freq = <0>;
+		num-moving-avg = <4>;
+
+		ts1: button1 {
+			compatible = "renesas,ra-ctsu-button";
+			event-code = <INPUT_KEY_1>;
+			elements = <0>;
+			threshold = <2305>;
+			hysteresis = <115>;
+		};
+	};
+};

drivers/input/CMakeLists.txt

@@ -31,6 +31,7 @@ zephyr_library_sources_ifdef(CONFIG_INPUT_PAW32XX input_paw32xx.c)
 zephyr_library_sources_ifdef(CONFIG_INPUT_PINNACLE input_pinnacle.c)
 zephyr_library_sources_ifdef(CONFIG_INPUT_PMW3610 input_pmw3610.c)
 zephyr_library_sources_ifdef(CONFIG_INPUT_REALTEK_RTS5912_KBD input_realtek_rts5912_kbd.c)
+zephyr_library_sources_ifdef(CONFIG_INPUT_RENESAS_RA_CTSU input_renesas_ra_ctsu.c)
 zephyr_library_sources_ifdef(CONFIG_INPUT_SBUS input_sbus.c)
 zephyr_library_sources_ifdef(CONFIG_INPUT_STM32_TSC_KEYS input_tsc_keys.c)
 zephyr_library_sources_ifdef(CONFIG_INPUT_STMPE811 input_stmpe811.c)

drivers/input/Kconfig

@@ -32,6 +32,7 @@ source "drivers/input/Kconfig.pat912x"
 source "drivers/input/Kconfig.paw32xx"
 source "drivers/input/Kconfig.pinnacle"
 source "drivers/input/Kconfig.pmw3610"
+source "drivers/input/Kconfig.renesas_ra"
 source "drivers/input/Kconfig.rts5912"
 source "drivers/input/Kconfig.sbus"
 source "drivers/input/Kconfig.sdl"

drivers/input/Kconfig.renesas_ra

@@ -0,0 +1,96 @@
+# Copyright (c) 2025 Renesas Electronics Corporation
+# SPDX-License-Identifier: Apache-2.0
+
+config INPUT_RENESAS_RA_CTSU
+	bool "Renesas RA Capacitive Touch driver"
+	default y
+	depends on DT_HAS_RENESAS_RA_CTSU_ENABLED
+	select USE_RA_FSP_CTSU
+	select USE_RA_FSP_TOUCH
+	select SYS_MEM_BLOCKS
+	select GPIO
+	select PINCTRL
+	help
+	  Enable Renesas RA Touch Sensing driver.
+
+if INPUT_RENESAS_RA_CTSU
+
+config INPUT_RENESAS_RA_DEVICE_VCC
+	int "SoC VCC input in minivolt"
+	default 3300
+	help
+	  SoC VCC input in milivolt.
+
+config INPUT_RENESAS_RA_QE_TOUCH_CFG
+	bool "Using QE Touch Workflow to config this driver"
+	help
+	  If this config was enabled, setting for CTSU and Cap
+	  Touch driver will be reflected the setting that generated
+	  from QE Touch Workflow.
+	  Please add the generated C source files into the app CMakeLists
+	  to make the driver can using it.
+
+if !INPUT_RENESAS_RA_QE_TOUCH_CFG
+
+config INPUT_RENESAS_RA_CTSU_NUM_SELF_ELEMENTS
+	int "Number of self-capacitance elements"
+	default 0
+	help
+	  Number of self-capacitance elements in the CTSU.
+
+config INPUT_RENESAS_RA_CTSU_NUM_MUTUAL_ELEMENTS
+	int "Number of mutual-capacitance elements"
+	default 0
+	help
+	  Number of mutual-capacitance elements in the CTSU.
+
+choice INPUT_RENESAS_RA_CTSU_CHATTERING_SUPPRESSION_TYPE
+	prompt "Type of chattering suppression"
+	default INPUT_RENESAS_RA_CTSU_CHATTERING_SUPPRESSION_TYPE_A
+
+config INPUT_RENESAS_RA_CTSU_CHATTERING_SUPPRESSION_TYPE_A
+	bool "Counter of exceed threshold is hold within hysteresis range"
+	help
+	  Counter of exceed threshold is hold within hysteresis range.
+
+config INPUT_RENESAS_RA_CTSU_CHATTERING_SUPPRESSION_TYPE_B
+	bool "Counter of exceed threshold is reset within hysteresis range"
+	help
+	  Counter of exceed threshold is reset within hysteresis range.
+
+endchoice # INPUT_RENESAS_RA_CTSU_CHATTERING_SUPPRESSION_TYPE
+
+endif # !INPUT_RENESAS_RA_QE_TOUCH_CFG
+
+config INPUT_RENESAS_RA_CTSU_POLLING_INTERVAL_MS
+	int "CTSU debounce interval time"
+	range 20 500
+	default 100
+	help
+	  Debouncing interval time in milliseconds.
+
+config INPUT_RENESAS_RA_CTSU_STABILIZATION_TIME_US
+	int "CTSU stabilization time"
+	default 20
+	help
+	  Stabilization time required to wait between 2 scans.
+
+config INPUT_RENESAS_RA_CTSU_DRV_STACK_SIZE
+	int "CTSU internal thread stack size"
+	default 512
+	help
+	  CTSU driver internal thread stack size.
+
+config INPUT_RENESAS_RA_CTSU_DRV_PRIORITY
+	int "CTSU internal thread priority"
+	default 8
+	help
+	  CTSU driver internal thread priority.
+
+config INPUT_RENESAS_RA_CTSU_MSG_MEM_BLOCK_SIZE
+	int "CTSU internal sys_mem_blocks allocator size"
+	default 10
+	help
+	  CTSU driver internal sys_mem_blocks allocator maximum num blocks.
+
+endif # INPUT_RENESAS_RA_CTSU