linux-kernel - [PATCH v2 2/2] Input: goodix - Allow DT specification of missing reset pull-up

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Message-Id: <20250429-goodix-no-reset-pull-up-v2-2-0687a4ad5a04@geanix.com>
Date: Tue, 29 Apr 2025 11:56:12 +0200
From: Esben Haabendal <esben@...nix.com>
To: Dmitry Torokhov <dmitry.torokhov@...il.com>, 
 Rob Herring <robh@...nel.org>, Krzysztof Kozlowski <krzk+dt@...nel.org>, 
 Conor Dooley <conor+dt@...nel.org>, Hans de Goede <hdegoede@...hat.com>
Cc: linux-input@...r.kernel.org, devicetree@...r.kernel.org, 
 linux-kernel@...r.kernel.org, Esben Haabendal <esben@...nix.com>
Subject: [PATCH v2 2/2] Input: goodix - Allow DT specification of missing
 reset pull-up

In commit a2fd46cd3dbb ("Input: goodix - try not to touch the reset-pin on x86/ACPI devices")
a fix for problems on various x86/ACPI devices where external
pull-up is missing were added. The same type of problem can exist on
device-tree platforms, and the fix can be activated by adding the
no-reset-pull-up device-tree property.

Signed-off-by: Esben Haabendal <esben@...nix.com>
Reviewed-by: Hans de Goede <hdegoede@...hat.com>
---
 drivers/input/touchscreen/goodix.c | 15 ++++++++++++---
 1 file changed, 12 insertions(+), 3 deletions(-)

diff --git a/drivers/input/touchscreen/goodix.c b/drivers/input/touchscreen/goodix.c
index a3e8a51c91449533b4d5185746df6b98676053dd..ce4622bbcc89434a4d89c49bb97f084fb61aa448 100644
--- a/drivers/input/touchscreen/goodix.c
+++ b/drivers/input/touchscreen/goodix.c
@@ -772,10 +772,12 @@ int goodix_reset_no_int_sync(struct goodix_ts_data *ts)
 
 	/*
 	 * Put the reset pin back in to input / high-impedance mode to save
-	 * power. Only do this in the non ACPI case since some ACPI boards
-	 * don't have a pull-up, so there the reset pin must stay active-high.
+	 * power.
+	 * Avoid doing this on boards that are known to not have external
+	 * pull-up, and all ACPI boards since some ACPI boards don't have a
+	 * pull-up. These boards need the reset pin to stay active-high.
 	 */
-	if (ts->irq_pin_access_method == IRQ_PIN_ACCESS_GPIO) {
+	if (ts->gpiod_rst_flags == GPIOD_IN) {
 		error = gpiod_direction_input(ts->gpiod_rst);
 		if (error)
 			goto error;
@@ -969,6 +971,13 @@ static int goodix_get_gpio_config(struct goodix_ts_data *ts)
 	 */
 	ts->gpiod_rst_flags = GPIOD_IN;
 
+	/*
+	 * Devices that does not have pull-up on reset signal should not be
+	 * changed to input
+	 */
+	if (device_property_read_bool(dev, "goodix,no-reset-pull-up"))
+		ts->gpiod_rst_flags = GPIOD_ASIS;
+
 	ts->avdd28 = devm_regulator_get(dev, "AVDD28");
 	if (IS_ERR(ts->avdd28))
 		return dev_err_probe(dev, PTR_ERR(ts->avdd28), "Failed to get AVDD28 regulator\n");

-- 
2.49.0