linux-kernel - [PATCH 02/14] iio: pressure: mprls0025pa: remove redundant mutex

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Message-Id: <20251218-mprls_cleanup-v1-2-b36a170f1a5c@subdimension.ro>
Date: Thu, 18 Dec 2025 13:05:44 +0200
From: Petre Rodan <petre.rodan@...dimension.ro>
To: Jonathan Cameron <jic23@...nel.org>, 
 David Lechner <dlechner@...libre.com>, 
 Nuno Sá <nuno.sa@...log.com>, 
 Andy Shevchenko <andy@...nel.org>, Andreas Klinger <ak@...klinger.de>
Cc: linux-iio@...r.kernel.org, linux-kernel@...r.kernel.org, 
 Jonathan Cameron <Jonathan.Cameron@...wei.com>
Subject: [PATCH 02/14] iio: pressure: mprls0025pa: remove redundant mutex

Remove the redundant mutex since both i2c and spi transfer functions
provide their own locking mechanism.

Signed-off-by: Petre Rodan <petre.rodan@...dimension.ro>
---
 drivers/iio/pressure/mprls0025pa.c | 6 ------
 drivers/iio/pressure/mprls0025pa.h | 3 ---
 2 files changed, 9 deletions(-)

diff --git a/drivers/iio/pressure/mprls0025pa.c b/drivers/iio/pressure/mprls0025pa.c
index 2336f2760eae..d3e76eed07e6 100644
--- a/drivers/iio/pressure/mprls0025pa.c
+++ b/drivers/iio/pressure/mprls0025pa.c
@@ -188,7 +188,6 @@ static void mpr_reset(struct mpr_data *data)
  * If there is an end of conversion (EOC) interrupt registered the function
  * waits for a maximum of one second for the interrupt.
  *
- * Context: The function can sleep and data->lock should be held when calling it
  * Return:
  * * 0		- OK, the pressure value could be read
  * * -ETIMEDOUT	- Timeout while waiting for the EOC interrupt or busy flag is
@@ -273,7 +272,6 @@ static irqreturn_t mpr_trigger_handler(int irq, void *p)
 	struct iio_dev *indio_dev = pf->indio_dev;
 	struct mpr_data *data = iio_priv(indio_dev);
 
-	mutex_lock(&data->lock);
 	ret = mpr_read_pressure(data, &data->chan.pres);
 	if (ret < 0)
 		goto err;
@@ -282,7 +280,6 @@ static irqreturn_t mpr_trigger_handler(int irq, void *p)
 					   iio_get_time_ns(indio_dev));
 
 err:
-	mutex_unlock(&data->lock);
 	iio_trigger_notify_done(indio_dev->trig);
 
 	return IRQ_HANDLED;
@@ -300,9 +297,7 @@ static int mpr_read_raw(struct iio_dev *indio_dev,
 
 	switch (mask) {
 	case IIO_CHAN_INFO_RAW:
-		mutex_lock(&data->lock);
 		ret = mpr_read_pressure(data, &pressure);
-		mutex_unlock(&data->lock);
 		if (ret < 0)
 			return ret;
 		*val = pressure;
@@ -342,7 +337,6 @@ int mpr_common_probe(struct device *dev, const struct mpr_ops *ops, int irq)
 	data->ops = ops;
 	data->irq = irq;
 
-	mutex_init(&data->lock);
 	init_completion(&data->completion);
 
 	indio_dev->name = "mprls0025pa";
diff --git a/drivers/iio/pressure/mprls0025pa.h b/drivers/iio/pressure/mprls0025pa.h
index d62a018eaff3..d38ac750e392 100644
--- a/drivers/iio/pressure/mprls0025pa.h
+++ b/drivers/iio/pressure/mprls0025pa.h
@@ -14,7 +14,6 @@
 #include <linux/completion.h>
 #include <linux/delay.h>
 #include <linux/device.h>
-#include <linux/mutex.h>
 #include <linux/stddef.h>
 #include <linux/types.h>
 
@@ -44,7 +43,6 @@ enum mpr_func_id {
  * struct mpr_data
  * @dev: current device structure
  * @ops: functions that implement the sensor reads/writes, bus init
- * @lock: access to device during read
  * @pmin: minimal pressure in pascal
  * @pmax: maximal pressure in pascal
  * @function: transfer function
@@ -66,7 +64,6 @@ enum mpr_func_id {
 struct mpr_data {
 	struct device		*dev;
 	const struct mpr_ops	*ops;
-	struct mutex		lock;
 	u32			pmin;
 	u32			pmax;
 	enum mpr_func_id	function;

-- 
2.51.2