iio: imu: adis: rename txrx_lock -> state_lock

The lock can be extended a bit to protect other elements that are not
particular to just TX/RX. Another idea would have been to just add a new
`state_lock`, but that would mean 2 locks which would be redundant, and
probably cause more potential for dead-locks.

What will be done in the next patches, will be to add some unlocked
versions for read/write_reg functions.
Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

drivers/iio/imu/adis.c

@@ -70,7 +70,7 @@ int adis_write_reg(struct adis *adis, unsigned int reg,
 		},
 	};
 
-	mutex_lock(&adis->txrx_lock);
+	mutex_lock(&adis->state_lock);
 
 	spi_message_init(&msg);
 
@@ -114,7 +114,7 @@ int adis_write_reg(struct adis *adis, unsigned int reg,
 	}
 
 out_unlock:
-	mutex_unlock(&adis->txrx_lock);
+	mutex_unlock(&adis->state_lock);
 
 	return ret;
 }
@@ -166,7 +166,7 @@ int adis_read_reg(struct adis *adis, unsigned int reg,
 		},
 	};
 
-	mutex_lock(&adis->txrx_lock);
+	mutex_lock(&adis->state_lock);
 	spi_message_init(&msg);
 
 	if (adis->current_page != page) {
@@ -211,7 +211,7 @@ int adis_read_reg(struct adis *adis, unsigned int reg,
 	}
 
 out_unlock:
-	mutex_unlock(&adis->txrx_lock);
+	mutex_unlock(&adis->state_lock);
 
 	return ret;
 }
@@ -438,7 +438,7 @@ EXPORT_SYMBOL_GPL(adis_single_conversion);
 int adis_init(struct adis *adis, struct iio_dev *indio_dev,
 	struct spi_device *spi, const struct adis_data *data)
 {
-	mutex_init(&adis->txrx_lock);
+	mutex_init(&adis->state_lock);
 	adis->spi = spi;
 	adis->data = data;
 	iio_device_set_drvdata(indio_dev, adis);

drivers/iio/imu/adis_buffer.c

@@ -129,7 +129,7 @@ static irqreturn_t adis_trigger_handler(int irq, void *p)
 		return -ENOMEM;
 
 	if (adis->data->has_paging) {
-		mutex_lock(&adis->txrx_lock);
+		mutex_lock(&adis->state_lock);
 		if (adis->current_page != 0) {
 			adis->tx[0] = ADIS_WRITE_REG(ADIS_REG_PAGE_ID);
 			adis->tx[1] = 0;
@@ -144,7 +144,7 @@ static irqreturn_t adis_trigger_handler(int irq, void *p)
 
 	if (adis->data->has_paging) {
 		adis->current_page = 0;
-		mutex_unlock(&adis->txrx_lock);
+		mutex_unlock(&adis->state_lock);
 	}
 
 	iio_push_to_buffers_with_timestamp(indio_dev, adis->buffer,

include/linux/iio/imu/adis.h

@@ -61,7 +61,7 @@ struct adis {
 	const struct adis_data	*data;
 	struct adis_burst	*burst;
 
-	struct mutex		txrx_lock;
+	struct mutex		state_lock;
 	struct spi_message	msg;
 	struct spi_transfer	*xfer;
 	unsigned int		current_page;