[PATCH v2 2/3] iio: imu: adis16400: fix unprotected debugfs reads

[Arka Mondal <arkamondalofficial@gmail.com>]

adis16400_serial_number_fops is open coded and never calls
debugfs_file_get(), so debugfs_remove_recursive() does not wait for a
read in progress and unbind frees the iio_dev underneath it.

Commit ae1d37a9bb4b ("iio: imu: adis16400: use DEFINE_DEBUGFS_ATTRIBUTE
instead of DEFINE_SIMPLE_ATTRIBUTE") converted product_id and
flash_count to DEFINE_DEBUGFS_ATTRIBUTE, which protects itself, but
moved all three files to debugfs_create_file_unsafe().

serial_number prints three registers as "%.4x-%.4x-%.4x" and
DEFINE_DEBUGFS_ATTRIBUTE() formats a single u64, so it cannot be
converted without changing what the file returns. adis16475 and
adis16550 already use debugfs_create_file() for their open coded
files. Use it here too.

Fixes: ae1d37a9bb4b ("iio: imu: adis16400: use DEFINE_DEBUGFS_ATTRIBUTE instead of DEFINE_SIMPLE_ATTRIBUTE")
Signed-off-by: Arka Mondal <arkamondalofficial@gmail.com>
---

Notes:
    Compile tested only; no relevant hardware available.

 drivers/iio/imu/adis16400.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/iio/imu/adis16400.c b/drivers/iio/imu/adis16400.c
index 36323ad149e0..7e85c1b8dc16 100644
--- a/drivers/iio/imu/adis16400.c
+++ b/drivers/iio/imu/adis16400.c
@@ -280,7 +280,7 @@ static void adis16400_debugfs_init(struct iio_dev *indio_dev)
 		return;
 
 	if (st->variant->flags & ADIS16400_HAS_SERIAL_NUMBER)
-		debugfs_create_file_unsafe("serial_number", 0400,
+		debugfs_create_file("serial_number", 0400,
 				d, st, &adis16400_serial_number_fops);
 	if (st->variant->flags & ADIS16400_HAS_PROD_ID)
 		debugfs_create_file_unsafe("product_id", 0400,
-- 
2.55.0