linux-kernel - [PATCH 3/6] Input: tsc2004/5 - fix reset handling on probe

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Message-ID: <20240711172719.1248373-3-dmitry.torokhov@gmail.com>
Date: Thu, 11 Jul 2024 10:27:14 -0700
From: Dmitry Torokhov <dmitry.torokhov@...il.com>
To: linux-input@...r.kernel.org,
	Sebastian Reichel <sre@...nel.org>
Cc: linux-kernel@...r.kernel.org
Subject: [PATCH 3/6] Input: tsc2004/5 - fix reset handling on probe

When the driver has been converted to use gpiod API it was requesting
and asserting the reset on probe, but never deasserted it. However
because of incorrect annotations in device tree marking reset line as
active high whereas in reality it is active low, the end result was
that the chip was never reset on probe. With polarity of the reset line
now corrected this became a problem.

Fix this by calling tsc200x_reset() from tsc200x_probe() to properly
complete the reset sequence and move requesting the reset GPIO and VIO
supply closer to the point where we need to start talking to the
hardware.

Fixes: d257f2980feb ("Input: tsc2005 - convert to gpiod")
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@...il.com>
---
 drivers/input/touchscreen/tsc200x-core.c | 28 +++++++++++++-----------
 1 file changed, 15 insertions(+), 13 deletions(-)

diff --git a/drivers/input/touchscreen/tsc200x-core.c b/drivers/input/touchscreen/tsc200x-core.c
index cd539a2a1dd5..87e6839c60fa 100644
--- a/drivers/input/touchscreen/tsc200x-core.c
+++ b/drivers/input/touchscreen/tsc200x-core.c
@@ -486,19 +486,6 @@ int tsc200x_probe(struct device *dev, int irq, const struct input_id *tsc_id,
 					 &esd_timeout);
 	ts->esd_timeout = error ? 0 : esd_timeout;
 
-	ts->reset_gpio = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_HIGH);
-	if (IS_ERR(ts->reset_gpio)) {
-		error = PTR_ERR(ts->reset_gpio);
-		dev_err(dev, "error acquiring reset gpio: %d\n", error);
-		return error;
-	}
-
-	error = devm_regulator_get_enable(dev, "vio");
-	if (error) {
-		dev_err(dev, "error acquiring vio regulator: %d\n", error);
-		return error;
-	}
-
 	mutex_init(&ts->mutex);
 
 	spin_lock_init(&ts->lock);
@@ -539,6 +526,21 @@ int tsc200x_probe(struct device *dev, int irq, const struct input_id *tsc_id,
 
 	touchscreen_parse_properties(input_dev, false, &ts->prop);
 
+	ts->reset_gpio = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_HIGH);
+	error = PTR_ERR_OR_ZERO(ts->reset_gpio);
+	if (error) {
+		dev_err(dev, "error acquiring reset gpio: %d\n", error);
+		return error;
+	}
+
+	error = devm_regulator_get_enable(dev, "vio");
+	if (error) {
+		dev_err(dev, "error acquiring vio regulator: %d\n", error);
+		return error;
+	}
+
+	tsc200x_reset(ts);
+
 	/* Ensure the touchscreen is off */
 	tsc200x_stop_scan(ts);
 
-- 
2.45.2.993.g49e7a77208-goog