iio: adc: ad9081: use guard(mutex) to protect critical sections

Add guard(mutex) to ad9081_status_show() and ad9081_fir_bin_write()
to ensure proper locking when accessing converter state. This prevents
potential race conditions during debugfs interactions.

Signed-off-by: Michael Hennerich <[email protected]>
(cherry picked from commit 70b58c6)

Author: mhennerich

drivers/iio/adc/ad9081.c

@@ -3206,6 +3206,8 @@ static int ad9081_status_show(struct seq_file *file, void *offset)
 	u16 stat;
 	u8 vals[3];
 
+	guard(mutex)(&conv->lock);
+
 	for (l = AD9081_LINK_0; !phy->tx_disable && (l < (ad9081_link_is_dual(phy->jrx_link_tx) ?
 		AD9081_LINK_ALL : AD9081_LINK_1)); l++) {
 
@@ -3260,9 +3262,6 @@ static int ad9081_status_show(struct seq_file *file, void *offset)
 	return 0;
 }
 
-
-
-
 static void ad9081_work_func(struct work_struct *work)
 {
 	u8 status;
@@ -3568,6 +3567,8 @@ ad9081_fir_bin_write(struct file *filp, struct kobject *kobj,
 	struct axiadc_converter *conv = iio_device_get_drvdata(indio_dev);
 	struct ad9081_phy *phy = conv->phy;
 
+	guard(mutex)(&conv->lock);
+
 	return ad9081_parse_fir(phy, buf, count);
 }