[PATCH v5 3/8] iio: imu: adis: Add optional init callback

[Radu Sabau via B4 Relay <devnull+radu.sabau.analog.com@kernel.org>]

From: Radu Sabau <radu.sabau@analog.com>

Add an optional init callback to struct adis_data, called right
after reset and before self-test. Not all ADIS devices need extra
bring-up between reset and self-test (SPI mode locking, status or
bootloader checks, pin or burst-mode configuration, etc.) - purely
additive: defaults to NULL, no change for existing drivers.

Signed-off-by: Radu Sabau <radu.sabau@analog.com>
---
 drivers/iio/imu/adis.c       | 6 ++++++
 include/linux/iio/imu/adis.h | 7 +++++++
 2 files changed, 13 insertions(+)

diff --git a/drivers/iio/imu/adis.c b/drivers/iio/imu/adis.c
index 5c3bb7259037..e2cf42b8b946 100644
--- a/drivers/iio/imu/adis.c
+++ b/drivers/iio/imu/adis.c
@@ -419,6 +419,12 @@ int __adis_initial_startup(struct adis *adis)
 		msleep(timeouts->sw_reset_ms);
 	}
 
+	if (adis->data->init) {
+		ret = adis->data->init(adis);
+		if (ret)
+			return ret;
+	}
+
 	ret = adis_self_test(adis);
 	if (ret)
 		return ret;
diff --git a/include/linux/iio/imu/adis.h b/include/linux/iio/imu/adis.h
index c09b381eb619..c9016f636530 100644
--- a/include/linux/iio/imu/adis.h
+++ b/include/linux/iio/imu/adis.h
@@ -52,6 +52,12 @@ struct adis_timeout {
  * @self_test_mask: Bitmask of supported self-test operations
  * @self_test_reg: Register address to request self test command
  * @self_test_no_autoclear: True if device's self-test needs clear of ctrl reg
+ * @init: Optional device-specific hook called after reset,
+ *		before self-test. Not all ADIS devices need extra bring-up
+ *		between reset and self-test (SPI mode locking, status or
+ *		bootloader checks, pin or burst-mode configuration, etc.) -
+ *		only called when set. Must return 0 on success, a negative
+ *		error code otherwise.
  * @self_test: Optional device-specific self-test override. When set,
  *		it is called instead of the generic mask-write/sleep/
  *		check-status sequence. The callback owns its own pass/fail
@@ -88,6 +94,7 @@ struct adis_data {
 	unsigned int self_test_mask;
 	unsigned int self_test_reg;
 	bool self_test_no_autoclear;
+	int (*init)(struct adis *adis);
 	int (*self_test)(struct adis *adis);
 	const struct adis_timeout *timeouts;
 

-- 
2.43.0