[PATCH RFC 0/3] Input: add EKTP1059 Touchpad

[PATCH RFC 0/3] Input: add EKTP1059 Touchpad

[Andreas Kemnade]

Add a driver and bindings for the Touchpad found in the Epson Moverio
BT-200. The only information source is the driver in the vendor kernel.
Besides of cleanup it differs from it by not doing much postprocessing.

The touchpad has no buttons and can react to three simultanous touches
but positions can be used only for two touches.

This is an early RFC, maybe somebody recognizes something from other
ELAN chips.

Signed-off-by: Andreas Kemnade <andreas@kemnade.info>
---
Andreas Kemnade (3):
      dt-bindings: input: elan: Introduce Elan eKTP1059 Touchpad
      Input: Add driver for Elan eKTP1059 Touchpad
      ARM: dts: ti/omap: epson-bt2ws: add touchpad

 .../devicetree/bindings/input/elan,ektp1059.yaml   |  45 ++++
 arch/arm/boot/dts/ti/omap/omap4-epson-embt2ws.dts  |  32 +++
 drivers/input/mouse/Kconfig                        |  10 +
 drivers/input/mouse/Makefile                       |   1 +
 drivers/input/mouse/elan_ektp1059.c                | 267 +++++++++++++++++++++
 5 files changed, 355 insertions(+)
---
base-commit: 1b237f190eb3d36f52dffe07a40b5eb210280e00
change-id: 20250824-ektp-submit-338c4bc30503

Best regards,
--  
Andreas Kemnade <andreas@kemnade.info>

[PATCH RFC 1/3] dt-bindings: input: elan: Introduce Elan eKTP1059 Touchpad

[Andreas Kemnade]

The Elan eKTP1059 Touchpad is seen in the Epson Moverio BT-200
attached via SPI. Add a binding for this chip. Little is known.

Signed-off-by: Andreas Kemnade <andreas@kemnade.info>
---
 .../devicetree/bindings/input/elan,ektp1059.yaml   | 45 ++++++++++++++++++++++
 1 file changed, 45 insertions(+)

diff --git a/Documentation/devicetree/bindings/input/elan,ektp1059.yaml b/Documentation/devicetree/bindings/input/elan,ektp1059.yaml
new file mode 100644
index 000000000000..a10256a271e0
--- /dev/null
+++ b/Documentation/devicetree/bindings/input/elan,ektp1059.yaml
@@ -0,0 +1,45 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/input/elan,ektp1059.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Elantech SPI Touchpad
+
+maintainers:
+  - Andreas Kemnade <andreas@kemnade.info>
+
+allOf:
+  - $ref: touchscreen/touchscreen.yaml#
+
+properties:
+  compatible:
+    const: elan,ektp1059
+
+  reg:
+    maxItems: 1
+
+  interrupts:
+    maxItems: 1
+
+required:
+  - compatible
+  - reg
+  - interrupts
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/interrupt-controller/irq.h>
+    spi {
+        #address-cells = <1>;
+        #size-cells = <0>;
+
+        touchpad@0 {
+            compatible = "elan,ektp1059";
+            reg = <0x0>;
+            interrupt-parent = <&gpio4>;
+            interrupts = <0x0 IRQ_TYPE_LEVEL_LOW>;
+        };
+    };

-- 
2.39.5

[PATCH RFC 2/3] Input: Add driver for Elan eKTP1059 Touchpad

[Andreas Kemnade]

Add driver for Elan eKTP1059 Touchpad connected via SPI.
No information found whether it could be alternatively connected via I2C.
No details about protocol are known, the only information is found in the
vendor kernel of the Epson Moverio BT-200, drivers/input/elan
http://epsonservice.goepson.com/downloads/VI-APS/BT200_kernel.tgz

Known issues: After some time (minutes) touching it, interrupts
stop arriving. Chances are that source of this problem is outside
of the driver.

Signed-off-by: Andreas Kemnade <andreas@kemnade.info>
---
 drivers/input/mouse/Kconfig         |  10 ++
 drivers/input/mouse/Makefile        |   1 +
 drivers/input/mouse/elan_ektp1059.c | 267 ++++++++++++++++++++++++++++++++++++
 3 files changed, 278 insertions(+)

diff --git a/drivers/input/mouse/Kconfig b/drivers/input/mouse/Kconfig
index 833b643f0616..5b197bd8863b 100644
--- a/drivers/input/mouse/Kconfig
+++ b/drivers/input/mouse/Kconfig
@@ -300,6 +300,16 @@ config MOUSE_ELAN_I2C_SMBUS
 
 	   If unsure, say Y.
 
+config MOUSE_ELAN_EKTP1059
+	tristate "Elan EKTP1059 Touchpad"
+	depends on SPI
+	help
+	  Say Y here if you have an Elan ETKP1059 touchpad connected
+	  via SPI.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called elan_ektp1059.
+
 config MOUSE_INPORT
 	tristate "InPort/MS/ATIXL busmouse"
 	depends on ISA
diff --git a/drivers/input/mouse/Makefile b/drivers/input/mouse/Makefile
index a1336d5bee6f..f6160a4c97c7 100644
--- a/drivers/input/mouse/Makefile
+++ b/drivers/input/mouse/Makefile
@@ -11,6 +11,7 @@ obj-$(CONFIG_MOUSE_ATARI)		+= atarimouse.o
 obj-$(CONFIG_MOUSE_BCM5974)		+= bcm5974.o
 obj-$(CONFIG_MOUSE_CYAPA)		+= cyapatp.o
 obj-$(CONFIG_MOUSE_ELAN_I2C)		+= elan_i2c.o
+obj-$(CONFIG_MOUSE_ELAN_EKTP1059)	+= elan_ektp1059.o
 obj-$(CONFIG_MOUSE_GPIO)		+= gpio_mouse.o
 obj-$(CONFIG_MOUSE_INPORT)		+= inport.o
 obj-$(CONFIG_MOUSE_LOGIBM)		+= logibm.o
diff --git a/drivers/input/mouse/elan_ektp1059.c b/drivers/input/mouse/elan_ektp1059.c
new file mode 100644
index 000000000000..a8ed7ba20e64
--- /dev/null
+++ b/drivers/input/mouse/elan_ektp1059.c
@@ -0,0 +1,267 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Elantech eKTP1059 SPI Touchpad
+ * Copyright (C) 2025 Andreas Kemnade <andreas@kemnade.info>
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/interrupt.h>
+#include <linux/errno.h>
+#include <linux/sched.h>
+#include <linux/delay.h>
+#include <linux/io.h>
+#include <linux/err.h>
+#include <linux/spi/spi.h>
+#include <linux/input.h>
+#include <linux/input/mt.h>
+#include <linux/kthread.h>
+
+#define TOUCHPAD_WIDTH		4000
+#define TOUCHPAD_HEIGHT		2426
+#define TOUCH_AREA		20
+#define PRESSURE_MAX 256
+
+struct elan_tp_spi {
+	struct input_dev *input_touch;
+	struct spi_device *spi;
+};
+
+static int elan_spi_write(struct elan_tp_spi *elanspi, const void *buf, size_t len)
+{
+	/*
+	 * running this as single transfer with word_delay set
+	 * results in an irq storm. Epson vendor kernel uses a single spi_sync
+	 * multiple 1 byte transfers.
+	 */
+	size_t i;
+	int err;
+
+	for (i = 0 ; i < len; i++) {
+		err = spi_write(elanspi->spi, buf, 1);
+		if (err)
+			return err;
+
+		udelay(100);
+	}
+	return 0;
+}
+
+static int elan_spi_read(struct elan_tp_spi *elanspi, void *buf, size_t len)
+{
+	/* reads 0x51 on sync */
+	struct spi_transfer t = { 0 };
+	int err;
+	size_t i;
+
+	for (i = 0; i < len; i++) {
+		u8 dummy = 0xff;
+
+		t.len = 1;
+		t.tx_buf = &dummy;
+		t.rx_buf = buf + i;
+		err = spi_sync_transfer(elanspi->spi, &t, 1);
+		if (err)
+			return err;
+
+		udelay(80);
+	}
+	return 0;
+}
+
+static irqreturn_t elan_tp_irq_handler(int irq, void *dev_id)
+{
+	struct elan_tp_spi *elanspi = dev_id;
+	u8 buf[14];
+	int fingercnt = 0;
+	int x, y, pres, width;
+
+	if (elan_spi_read(elanspi, buf, 14))
+		return IRQ_HANDLED;
+
+	if (buf[13] != 0x1)
+		return IRQ_HANDLED;
+
+	fingercnt = (buf[1] & 0xC0) >> 6;
+	input_report_key(elanspi->input_touch, BTN_TOUCH, fingercnt != 0);
+	input_report_key(elanspi->input_touch, BTN_TOOL_FINGER, fingercnt == 1);
+	input_report_key(elanspi->input_touch, BTN_TOOL_DOUBLETAP, fingercnt == 2);
+	input_report_key(elanspi->input_touch, BTN_TOOL_TRIPLETAP, fingercnt == 3);
+
+	x = buf[2] & 0xf;
+	x = x << 8;
+	x |= buf[3];
+	y = buf[5] & 0xf;
+	y = y << 8;
+	y |= buf[6];
+
+	pres = (buf[2] & 0xf0) | ((buf[5] & 0xf0) >> 4);
+	width = ((buf[1] & 0x30) >> 2) | ((buf[4] & 0x30) >> 4);
+
+	input_report_abs(elanspi->input_touch, ABS_PRESSURE, pres);
+	input_report_abs(elanspi->input_touch, ABS_TOOL_WIDTH, width);
+
+	if (fingercnt != 0) {
+		input_report_abs(elanspi->input_touch, ABS_X, x);
+		input_report_abs(elanspi->input_touch, ABS_Y, y);
+	}
+
+	input_mt_slot(elanspi->input_touch, 0);
+	input_mt_report_slot_state(elanspi->input_touch, MT_TOOL_FINGER, fingercnt == 1);
+
+	if (fingercnt != 0) {
+		input_report_abs(elanspi->input_touch, ABS_MT_POSITION_X, x);
+		input_report_abs(elanspi->input_touch, ABS_MT_POSITION_Y, y);
+	}
+	dev_dbg(&elanspi->spi->dev, "1: X: %d Y: %d pres: %d width: %d\n",
+		x, y, pres, width);
+
+	if (fingercnt >= 2) {
+		x = buf[8] & 0xf;
+		x = x << 8;
+		x |= buf[9];
+		y = buf[11] & 0xf;
+		y = y << 8;
+		y |= buf[12];
+		input_mt_slot(elanspi->input_touch, 1);
+		input_mt_report_slot_state(elanspi->input_touch, MT_TOOL_FINGER, 1);
+		input_report_abs(elanspi->input_touch, ABS_MT_POSITION_X, x);
+		input_report_abs(elanspi->input_touch, ABS_MT_POSITION_Y, y);
+		dev_dbg(&elanspi->spi->dev, "2: X: %d Y: %d\n", x, y);
+	} else {
+		input_mt_slot(elanspi->input_touch, 1);
+		input_mt_report_slot_state(elanspi->input_touch, MT_TOOL_FINGER, 0);
+	}
+
+	input_sync(elanspi->input_touch);
+
+	return IRQ_HANDLED;
+}
+
+static int handle_hello_package(struct elan_tp_spi *elanspi)
+{
+	u8 buf_recv[4];
+	int rc;
+
+	rc = elan_spi_read(elanspi, buf_recv, 4);
+	if (rc != 0)
+		return rc;
+
+	/* 0xa0, 0x7, 0x0, 0x0 after boot */
+	dev_dbg(&elanspi->spi->dev,
+		"dump hello packet: %x, %x, %x, %x\n",
+		buf_recv[0], buf_recv[1], buf_recv[2], buf_recv[3]);
+
+	return 0;
+}
+
+static int init_touchpad(struct elan_tp_spi *elanspi)
+{
+	u8 buf_cmd[4] = {0x5B, 0x10, 0xC, 0x1};
+	u8 buf[14];
+	int ret;
+
+	ret = elan_spi_write(elanspi, buf_cmd, 4);
+
+	if (ret != 0)
+		return ret;
+
+	msleep(20);
+	elan_spi_read(elanspi, buf, 14);
+
+	return 0;
+}
+
+static int elan_ektp1059_probe(struct spi_device *spi)
+{
+	int status = 0;
+	struct elan_tp_spi *elanspi;
+	struct input_dev *input_touch;
+
+	spi->bits_per_word = 8;
+	status = spi_setup(spi);
+
+	elanspi = devm_kzalloc(&spi->dev,
+			       sizeof(struct elan_tp_spi), GFP_KERNEL);
+	if (!elanspi)
+		return -ENOMEM;
+
+	input_touch = devm_input_allocate_device(&spi->dev);
+	if (!input_touch)
+		return dev_err_probe(&spi->dev, PTR_ERR(input_touch),
+				     "create input touch device failed\n");
+
+	elanspi->input_touch = input_touch;
+
+	elanspi->spi = spi;
+	spi_set_drvdata(spi, elanspi);
+
+	input_touch->name = "elan-touchpad";
+	input_set_abs_params(input_touch, ABS_MT_POSITION_X, 0, TOUCHPAD_WIDTH, 0, 0);
+	input_set_abs_params(input_touch, ABS_MT_POSITION_Y, 0, TOUCHPAD_HEIGHT, 0, 0);
+	input_set_abs_params(input_touch, ABS_MT_PRESSURE, 0, PRESSURE_MAX, 0, 0);
+	input_set_abs_params(input_touch, ABS_TOOL_WIDTH, 0, TOUCH_AREA, 0, 0);
+	input_mt_init_slots(input_touch, 3, INPUT_MT_POINTER | INPUT_MT_SEMI_MT);
+	input_set_drvdata(input_touch, elanspi);
+
+	status = input_register_device(input_touch);
+	if (status < 0)
+		return dev_err_probe(&elanspi->spi->dev, status, "input_register_device failed\n");
+
+	status = handle_hello_package(elanspi);
+	if (status < 0)
+		return dev_err_probe(&elanspi->spi->dev, status, "handle hello package failed\n");
+
+	status = init_touchpad(elanspi);
+	if (status < 0)
+		return dev_err_probe(&spi->dev, status, "init touchpad failed!\n");
+
+	status = devm_request_threaded_irq(&spi->dev, spi->irq, NULL,
+					   elan_tp_irq_handler, IRQF_ONESHOT,
+					   spi->dev.driver->name, elanspi);
+	if (status < 0)
+		return dev_err_probe(&spi->dev, status, "request_irq failed\n");
+
+	return 0;
+}
+
+static int elan_ektp1059_suspend(struct device *dev)
+{
+	disable_irq(to_spi_device(dev)->irq);
+	return 0;
+}
+
+static int elan_ektp1059_resume(struct device *dev)
+{
+	enable_irq(to_spi_device(dev)->irq);
+	return 0;
+}
+
+static const struct spi_device_id elan_ektp1059_id[] = {
+	{ "ektp1059", 0 },
+	{},
+};
+MODULE_DEVICE_TABLE(spi, elan_ektp1059_id);
+
+static const struct of_device_id elan_ektp1059_of_spi_match[] = {
+	{ .compatible = "elan,ektp1059" },
+	{ },
+};
+MODULE_DEVICE_TABLE(of, elan_ektp1059_of_spi_match);
+
+static SIMPLE_DEV_PM_OPS(elan_ektp1059_pm, elan_ektp1059_suspend, elan_ektp1059_resume);
+
+static struct spi_driver elan_ektp1059_driver = {
+	.driver	= {
+		.name	 = "elan_ektp1059",
+		.of_match_table = elan_ektp1059_of_spi_match,
+		.pm = pm_ptr(&elan_ektp1059_pm),
+	},
+	.id_table = elan_ektp1059_id,
+	.probe	= elan_ektp1059_probe,
+};
+
+module_spi_driver(elan_ektp1059_driver);
+
+MODULE_DESCRIPTION("Elan eKTP1059 SPI touch pad");
+MODULE_LICENSE("GPL");

-- 
2.39.5

[PATCH RFC 3/3] ARM: dts: ti/omap: epson-bt2ws: add touchpad

[Andreas Kemnade]

Add the EKTP1059 based touchpad connected via SPI.

Signed-off-by: Andreas Kemnade <andreas@kemnade.info>
---
 arch/arm/boot/dts/ti/omap/omap4-epson-embt2ws.dts | 32 +++++++++++++++++++++++
 1 file changed, 32 insertions(+)

diff --git a/arch/arm/boot/dts/ti/omap/omap4-epson-embt2ws.dts b/arch/arm/boot/dts/ti/omap/omap4-epson-embt2ws.dts
index c90f43cc2fae..746ac4761b0d 100644
--- a/arch/arm/boot/dts/ti/omap/omap4-epson-embt2ws.dts
+++ b/arch/arm/boot/dts/ti/omap/omap4-epson-embt2ws.dts
@@ -429,6 +429,23 @@ MATRIX_KEY(1, 1, KEY_VOLUMEDOWN)
 	linux,input-no-autorepeat;
 };
 
+&mcspi1 {
+	pinctrl-names = "default";
+	pinctrl-0 = <&mcspi1_pins>;
+
+	touchpad@0 {
+		compatible = "elan,ektp1059";
+		reg = <0>;      /* cs0 */
+		pinctrl-names = "default";
+		pinctrl-0 = <&elan_pins>;
+		interrupt-parent = <&gpio2>;
+		interrupts = <20 IRQ_TYPE_LEVEL_LOW>;
+		spi-max-frequency = <200000>;
+		spi-cpol;
+		spi-cpha;
+	};
+};
+
 &mcbsp2 {
 	#sound-dai-cells = <0>;
 	pinctrl-names = "default";
@@ -506,6 +523,12 @@ OMAP4_IOPAD(0x1d4, PIN_OUTPUT | MUX_MODE3) /* gpio191 */
 		>;
 	};
 
+	elan_pins: pinmux-elan-pins {
+		pinctrl-single,pins = <
+			OMAP4_IOPAD(0x78, PIN_INPUT | MUX_MODE3) /* gpio52 */
+		>;
+	};
+
 	gpio_keys_pins: pinmux-gpio-key-pins {
 		pinctrl-single,pins = <
 			OMAP4_IOPAD(0x56, PIN_INPUT_PULLUP | MUX_MODE3) /* gpio35 */
@@ -579,6 +602,15 @@ OMAP4_IOPAD(0x1ce, PIN_OUTPUT | MUX_MODE3) /* gpio27 */
 		>;
 	};
 
+	mcspi1_pins: pinmux-mcspi1-pins {
+		pinctrl-single,pins = <
+			OMAP4_IOPAD(0x132, PIN_INPUT_PULLUP | MUX_MODE0)
+			OMAP4_IOPAD(0x134, PIN_INPUT_PULLUP | MUX_MODE0)
+			OMAP4_IOPAD(0x136, PIN_OUTPUT | MUX_MODE0)
+			OMAP4_IOPAD(0x138, PIN_OUTPUT | MUX_MODE0)
+		>;
+	};
+
 	mcbsp2_pins: pinmux-mcbsp2-pins {
 		pinctrl-single,pins = <
 			OMAP4_IOPAD(0x0f6, PIN_INPUT | MUX_MODE0)       /* abe_mcbsp2_clkx */

-- 
2.39.5

Re: [PATCH RFC 1/3] dt-bindings: input: elan: Introduce Elan eKTP1059 Touchpad

[Conor Dooley]

[-- Attachment #1: Type: text/plain, Size: 1853 bytes --]

On Mon, Aug 25, 2025 at 12:07:28AM +0200, Andreas Kemnade wrote:
> The Elan eKTP1059 Touchpad is seen in the Epson Moverio BT-200
> attached via SPI. Add a binding for this chip. Little is known.
> 
> Signed-off-by: Andreas Kemnade <andreas@kemnade.info>
> ---
>  .../devicetree/bindings/input/elan,ektp1059.yaml   | 45 ++++++++++++++++++++++
>  1 file changed, 45 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/input/elan,ektp1059.yaml b/Documentation/devicetree/bindings/input/elan,ektp1059.yaml
> new file mode 100644
> index 000000000000..a10256a271e0
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/input/elan,ektp1059.yaml
> @@ -0,0 +1,45 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/input/elan,ektp1059.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Elantech SPI Touchpad
> +
> +maintainers:
> +  - Andreas Kemnade <andreas@kemnade.info>
> +
> +allOf:
> +  - $ref: touchscreen/touchscreen.yaml#
> +
> +properties:
> +  compatible:
> +    const: elan,ektp1059
> +
> +  reg:
> +    maxItems: 1
> +
> +  interrupts:
> +    maxItems: 1
> +
> +required:
> +  - compatible
> +  - reg
> +  - interrupts
> +
> +additionalProperties: false

Shouldn't this be unevalutedProperties: false, since you want to make
use of what's in touchscreen.yaml?

> +
> +examples:
> +  - |
> +    #include <dt-bindings/interrupt-controller/irq.h>
> +    spi {
> +        #address-cells = <1>;
> +        #size-cells = <0>;
> +
> +        touchpad@0 {
> +            compatible = "elan,ektp1059";
> +            reg = <0x0>;
> +            interrupt-parent = <&gpio4>;
> +            interrupts = <0x0 IRQ_TYPE_LEVEL_LOW>;
> +        };
> +    };
> 
> -- 
> 2.39.5
> 

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