diff --git a/drivers/iio/dac/ad3552r-hs.c b/drivers/iio/dac/ad3552r-hs.c
index 6bc64f53bce9..5d6c2517a7a8 100644
--- a/drivers/iio/dac/ad3552r-hs.c
+++ b/drivers/iio/dac/ad3552r-hs.c
@@ -591,7 +591,7 @@ static ssize_t ad3552r_hs_show_data_source_avail(struct file *f,
 	int i;
 
 	for (i = 0; i < ARRAY_SIZE(dbgfs_attr_source); i++) {
-		len += scnprintf(buf + len, PAGE_SIZE - len, "%s ",
+		len += scnprintf(buf + len, sizeof(buf) - len, "%s ",
 				 dbgfs_attr_source[i]);
 	}
 	buf[len - 1] = '\n';