[PATCH v2 0/3] novatek-nvt-ts: add support for NT36672A touchscreen

[PATCH v2 0/3] novatek-nvt-ts: add support for NT36672A touchscreen

[Joel Selvaraj via B4 Relay]

Extend the novatek touchscreen driver to support NT36672A chip which
is found in phones like Xiaomi Poco F1 [1]. Added devicetree support for
the driver and used i2c chip data to handle the variation in chip id and
wake type. Also added vcc and iovcc regulators which are used to power
the touchscreen hardware. 

[1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/arch/arm64/boot/dts/qcom/sdm845-xiaomi-beryllium-tianma.dts?h=v6.9

Signed-off-by: Joel Selvaraj <joelselvaraj.oss@gmail.com>
---
Changes in v2:
- The generic i2c device id is now replaced with the correct IC variant
  provided by Hans de Goede
- Updated the bindings to reflect the latest changes and also incorporated
  the suggestions provided by Krzysztof Kozlowski
- Link to v1: https://lore.kernel.org/r/20240521-nvt-ts-devicetree-regulator-support-v1-0-8d766c639dca@gmail.com

---
Joel Selvaraj (3):
      Input: novatek-nvt-ts: replace generic i2c device id with specific IC variant
      dt-bindings: input: document Novatek NVT touchscreen controller
      Input: novatek-nvt-ts: add support for NT36672A touchscreen

 .../bindings/input/touchscreen/novatek,nvt-ts.yaml | 62 +++++++++++++++++
 MAINTAINERS                                        |  1 +
 drivers/input/touchscreen/novatek-nvt-ts.c         | 78 ++++++++++++++++++++--
 drivers/platform/x86/x86-android-tablets/other.c   |  2 +-
 4 files changed, 136 insertions(+), 7 deletions(-)
---
base-commit: 6578aac6a270bd6deb9f9319b991dd430de263dd
change-id: 20240518-nvt-ts-devicetree-regulator-support-ac9e49b78a16

Best regards,
-- 
Joel Selvaraj <joelselvaraj.oss@gmail.com>

[PATCH v2 1/3] Input: novatek-nvt-ts: replace generic i2c device id with specific IC variant

[Joel Selvaraj via B4 Relay]

From: Joel Selvaraj <joelselvaraj.oss@gmail.com>

This is done in preparation to introduce other variants of the Novatek NVT
touchscreen controller that can be supported by the driver.

Signed-off-by: Joel Selvaraj <joelselvaraj.oss@gmail.com>
---
 drivers/input/touchscreen/novatek-nvt-ts.c       | 2 +-
 drivers/platform/x86/x86-android-tablets/other.c | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/input/touchscreen/novatek-nvt-ts.c b/drivers/input/touchscreen/novatek-nvt-ts.c
index 1a797e410a3fa..224fd112b25a9 100644
--- a/drivers/input/touchscreen/novatek-nvt-ts.c
+++ b/drivers/input/touchscreen/novatek-nvt-ts.c
@@ -278,7 +278,7 @@ static int nvt_ts_probe(struct i2c_client *client)
 }
 
 static const struct i2c_device_id nvt_ts_i2c_id[] = {
-	{ "NVT-ts" },
+	{ "NT11205-ts" },
 	{ }
 };
 MODULE_DEVICE_TABLE(i2c, nvt_ts_i2c_id);
diff --git a/drivers/platform/x86/x86-android-tablets/other.c b/drivers/platform/x86/x86-android-tablets/other.c
index eb0e55c69dfed..5ecee6e66fb4d 100644
--- a/drivers/platform/x86/x86-android-tablets/other.c
+++ b/drivers/platform/x86/x86-android-tablets/other.c
@@ -40,7 +40,7 @@ static const struct x86_i2c_client_info acer_b1_750_i2c_clients[] __initconst =
 	{
 		/* Novatek NVT-ts touchscreen */
 		.board_info = {
-			.type = "NVT-ts",
+			.type = "NT11205-ts",
 			.addr = 0x34,
 			.dev_name = "NVT-ts",
 		},

-- 
2.45.1

[PATCH v2 2/3] dt-bindings: input: document Novatek NVT touchscreen controller

[Joel Selvaraj via B4 Relay]

From: Joel Selvaraj <joelselvaraj.oss@gmail.com>

Document the Novatek NVT touchscreen controller present in devices like
the Xiaomi Poco F1 [1]. Also, include the devictree binding file in the
MAINTAINERS file.

[1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/arch/arm64/boot/dts/qcom/sdm845-xiaomi-beryllium-tianma.dts?h=v6.9

Signed-off-by: Joel Selvaraj <joelselvaraj.oss@gmail.com>
---
 .../bindings/input/touchscreen/novatek,nvt-ts.yaml | 62 ++++++++++++++++++++++
 MAINTAINERS                                        |  1 +
 2 files changed, 63 insertions(+)

diff --git a/Documentation/devicetree/bindings/input/touchscreen/novatek,nvt-ts.yaml b/Documentation/devicetree/bindings/input/touchscreen/novatek,nvt-ts.yaml
new file mode 100644
index 0000000000000..c47b4de9d58e7
--- /dev/null
+++ b/Documentation/devicetree/bindings/input/touchscreen/novatek,nvt-ts.yaml
@@ -0,0 +1,62 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/input/touchscreen/novatek,nvt-ts.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Novatek NVT Touchscreen Controller
+
+maintainers:
+  - Hans de Goede <hdegoede@redhat.com>
+
+allOf:
+  - $ref: touchscreen.yaml#
+
+properties:
+  compatible:
+    enum:
+      - novatek,nt11205-ts
+      - novatek,nt36672a-ts
+
+  reg:
+    maxItems: 1
+
+  interrupts:
+    maxItems: 1
+
+  reset-gpios:
+    maxItems: 1
+
+  vcc-supply: true
+  iovcc-supply: true
+
+required:
+  - compatible
+  - reg
+  - interrupts
+
+unevaluatedProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/gpio/gpio.h>
+    #include <dt-bindings/interrupt-controller/arm-gic.h>
+    i2c {
+        #address-cells = <1>;
+        #size-cells = <0>;
+        touchscreen@1 {
+          compatible = "novatek,nt36672a-ts";
+          reg = <0x01>;
+          interrupts-extended = <&tlmm 31 IRQ_TYPE_EDGE_RISING>;
+          reset-gpios = <&tlmm 32 GPIO_ACTIVE_LOW>;
+          vcc-supply = <&vreg_l22a_2p85>;
+          iovcc-supply = <&vreg_l14a_1p8>;
+          pinctrl-0 = <&ts_int_default &ts_reset_default>;
+          pinctrl-1 = <&ts_int_sleep &ts_reset_sleep>;
+          pinctrl-names = "default", "sleep";
+          touchscreen-size-x = <1080>;
+          touchscreen-size-y = <2246>;
+        };
+    };
+
+...
diff --git a/MAINTAINERS b/MAINTAINERS
index 90754a451bcfc..e1f744992b15f 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -15942,6 +15942,7 @@ NOVATEK NVT-TS I2C TOUCHSCREEN DRIVER
 M:	Hans de Goede <hdegoede@redhat.com>
 L:	linux-input@vger.kernel.org
 S:	Maintained
+F:	Documentation/devicetree/bindings/input/touchscreen/novatek,nvt-ts.yaml
 F:	drivers/input/touchscreen/novatek-nvt-ts.c
 
 NSDEPS

-- 
2.45.1

[PATCH v2 3/3] Input: novatek-nvt-ts: add support for NT36672A touchscreen

[Joel Selvaraj via B4 Relay]

From: Joel Selvaraj <joelselvaraj.oss@gmail.com>

Extend the novatek touchscreen driver to support NT36672A chip which
is found in phones like Xiaomi Poco F1 [1]. Added devicetree support for
the driver and used i2c chip data to handle the variation in chip id and
wake type. Also added vcc and iovcc regulators which are used to power
the touchscreen hardware.

[1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/arch/arm64/boot/dts/qcom/sdm845-xiaomi-beryllium-tianma.dts?h=v6.9

Signed-off-by: Joel Selvaraj <joelselvaraj.oss@gmail.com>
---
 drivers/input/touchscreen/novatek-nvt-ts.c | 78 +++++++++++++++++++++++++++---
 1 file changed, 72 insertions(+), 6 deletions(-)

diff --git a/drivers/input/touchscreen/novatek-nvt-ts.c b/drivers/input/touchscreen/novatek-nvt-ts.c
index 224fd112b25a9..7a82a1b09f9d5 100644
--- a/drivers/input/touchscreen/novatek-nvt-ts.c
+++ b/drivers/input/touchscreen/novatek-nvt-ts.c
@@ -31,9 +31,6 @@
 #define NVT_TS_PARAMS_CHIP_ID		0x0e
 #define NVT_TS_PARAMS_SIZE		0x0f
 
-#define NVT_TS_SUPPORTED_WAKE_TYPE	0x05
-#define NVT_TS_SUPPORTED_CHIP_ID	0x05
-
 #define NVT_TS_MAX_TOUCHES		10
 #define NVT_TS_MAX_SIZE			4096
 
@@ -51,11 +48,18 @@ static const int nvt_ts_irq_type[4] = {
 	IRQF_TRIGGER_HIGH
 };
 
+struct nvt_ts_i2c_chip_data {
+	u8 wake_type;
+	u8 chip_id;
+};
+
 struct nvt_ts_data {
 	struct i2c_client *client;
 	struct input_dev *input;
 	struct gpio_desc *reset_gpio;
+	struct regulator_bulk_data regulators[2];
 	struct touchscreen_properties prop;
+	const struct nvt_ts_i2c_chip_data *chip;
 	int max_touches;
 	u8 buf[NVT_TS_TOUCH_SIZE * NVT_TS_MAX_TOUCHES];
 };
@@ -139,9 +143,23 @@ static irqreturn_t nvt_ts_irq(int irq, void *dev_id)
 	return IRQ_HANDLED;
 }
 
+static void nvt_ts_disable_regulators(void *_data)
+{
+	struct nvt_ts_data *data = _data;
+
+	regulator_bulk_disable(ARRAY_SIZE(data->regulators), data->regulators);
+}
+
 static int nvt_ts_start(struct input_dev *dev)
 {
 	struct nvt_ts_data *data = input_get_drvdata(dev);
+	int error;
+
+	error = regulator_bulk_enable(ARRAY_SIZE(data->regulators), data->regulators);
+	if (error) {
+		dev_err(&data->client->dev, "failed to enable regulators\n");
+		return error;
+	}
 
 	enable_irq(data->client->irq);
 	gpiod_set_value_cansleep(data->reset_gpio, 0);
@@ -155,6 +173,7 @@ static void nvt_ts_stop(struct input_dev *dev)
 
 	disable_irq(data->client->irq);
 	gpiod_set_value_cansleep(data->reset_gpio, 1);
+	nvt_ts_disable_regulators(data);
 }
 
 static int nvt_ts_suspend(struct device *dev)
@@ -199,9 +218,37 @@ static int nvt_ts_probe(struct i2c_client *client)
 	if (!data)
 		return -ENOMEM;
 
+	data->chip = device_get_match_data(&client->dev);
+	if (!data->chip)
+		return -EINVAL;
+
 	data->client = client;
 	i2c_set_clientdata(client, data);
 
+	/*
+	 * VCC is the analog voltage supply
+	 * IOVCC is the digital voltage supply
+	 */
+	data->regulators[0].supply = "vcc";
+	data->regulators[1].supply = "iovcc";
+	error = devm_regulator_bulk_get(dev, ARRAY_SIZE(data->regulators), data->regulators);
+	if (error) {
+		dev_err(dev, "cannot get regulators: %d\n", error);
+		return error;
+	}
+
+	error = regulator_bulk_enable(ARRAY_SIZE(data->regulators), data->regulators);
+	if (error) {
+		dev_err(dev, "failed to enable regulators\n");
+		return error;
+	}
+
+	error = devm_add_action_or_reset(dev, nvt_ts_disable_regulators, data);
+	if (error) {
+		dev_err(dev, "failed to install regulator disable handler\n");
+		return error;
+	}
+
 	data->reset_gpio = devm_gpiod_get(dev, "reset", GPIOD_OUT_LOW);
 	error = PTR_ERR_OR_ZERO(data->reset_gpio);
 	if (error) {
@@ -225,8 +272,8 @@ static int nvt_ts_probe(struct i2c_client *client)
 	if (width > NVT_TS_MAX_SIZE || height >= NVT_TS_MAX_SIZE ||
 	    data->max_touches > NVT_TS_MAX_TOUCHES ||
 	    irq_type >= ARRAY_SIZE(nvt_ts_irq_type) ||
-	    data->buf[NVT_TS_PARAMS_WAKE_TYPE] != NVT_TS_SUPPORTED_WAKE_TYPE ||
-	    data->buf[NVT_TS_PARAMS_CHIP_ID] != NVT_TS_SUPPORTED_CHIP_ID) {
+	    data->buf[NVT_TS_PARAMS_WAKE_TYPE] != data->chip->wake_type ||
+	    data->buf[NVT_TS_PARAMS_CHIP_ID] != data->chip->chip_id) {
 		dev_err(dev, "Unsupported touchscreen parameters: %*ph\n",
 			NVT_TS_PARAMS_SIZE, data->buf);
 		return -EIO;
@@ -277,8 +324,26 @@ static int nvt_ts_probe(struct i2c_client *client)
 	return 0;
 }
 
+static const struct nvt_ts_i2c_chip_data nvt_nt11205_ts_data = {
+	.wake_type = 0x05,
+	.chip_id = 0x05,
+};
+
+static const struct nvt_ts_i2c_chip_data nvt_nt36672a_ts_data = {
+	.wake_type = 0x01,
+	.chip_id = 0x08,
+};
+
+static const struct of_device_id nvt_ts_of_match[] = {
+	{ .compatible = "novatek,nt11205-ts", .data = &nvt_nt11205_ts_data },
+	{ .compatible = "novatek,nt36672a-ts", .data = &nvt_nt36672a_ts_data },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, nvt_ts_of_match);
+
 static const struct i2c_device_id nvt_ts_i2c_id[] = {
-	{ "NT11205-ts" },
+	{ "NT11205-ts", (unsigned long) &nvt_nt11205_ts_data },
+	{ "NT36672A-ts", (unsigned long) &nvt_nt36672a_ts_data },
 	{ }
 };
 MODULE_DEVICE_TABLE(i2c, nvt_ts_i2c_id);
@@ -287,6 +352,7 @@ static struct i2c_driver nvt_ts_driver = {
 	.driver = {
 		.name	= "novatek-nvt-ts",
 		.pm	= pm_sleep_ptr(&nvt_ts_pm_ops),
+		.of_match_table = nvt_ts_of_match,
 	},
 	.probe = nvt_ts_probe,
 	.id_table = nvt_ts_i2c_id,

-- 
2.45.1

Re: [PATCH v2 2/3] dt-bindings: input: document Novatek NVT touchscreen controller

[Krzysztof Kozlowski]

On 24/05/2024 16:39, Joel Selvaraj via B4 Relay wrote:
> From: Joel Selvaraj <joelselvaraj.oss@gmail.com>
> 
> Document the Novatek NVT touchscreen controller present in devices like
> the Xiaomi Poco F1 [1]. Also, include the devictree binding file in the

Just name the DTS, no need for external link.

> MAINTAINERS file.
> 
> [1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/arch/arm64/boot/dts/qcom/sdm845-xiaomi-beryllium-tianma.dts?h=v6.9
> 


> +
> +  vcc-supply: true
> +  iovcc-supply: true
> +
> +required:
> +  - compatible
> +  - reg
> +  - interrupts
> +
> +unevaluatedProperties: false
> +
> +examples:
> +  - |
> +    #include <dt-bindings/gpio/gpio.h>
> +    #include <dt-bindings/interrupt-controller/arm-gic.h>
> +    i2c {
> +        #address-cells = <1>;
> +        #size-cells = <0>;
> +        touchscreen@1 {
> +          compatible = "novatek,nt36672a-ts";

Messed indentation. Use 4 spaces for example indentation.

With above fixes:

Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>


Best regards,
Krzysztof