[PATCH v6 7/8] media: subdev: add v4l2_subdev_get_fmt() helper function

[Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>]

Add v4l2_subdev_get_fmt() helper function which implements
v4l2_subdev_pad_ops.get_fmt using active state. Subdev drivers that
support active state and do not need to do anything special in their
get_fmt op can use this helper directly for v4l2_subdev_pad_ops.get_fmt.

Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
---
 drivers/media/v4l2-core/v4l2-subdev.c | 18 ++++++++++++++++++
 include/media/v4l2-subdev.h           | 17 +++++++++++++++++
 2 files changed, 35 insertions(+)

diff --git a/drivers/media/v4l2-core/v4l2-subdev.c b/drivers/media/v4l2-core/v4l2-subdev.c
index d8d1c9ef4dc4..cbc5ebff0656 100644
--- a/drivers/media/v4l2-core/v4l2-subdev.c
+++ b/drivers/media/v4l2-core/v4l2-subdev.c
@@ -1029,6 +1029,24 @@ void v4l2_subdev_cleanup(struct v4l2_subdev *sd)
 }
 EXPORT_SYMBOL_GPL(v4l2_subdev_cleanup);
 
+int v4l2_subdev_get_fmt(struct v4l2_subdev *sd, struct v4l2_subdev_state *state,
+			struct v4l2_subdev_format *format)
+{
+	struct v4l2_mbus_framefmt *fmt;
+
+	if (format->pad >= sd->entity.num_pads)
+		return -EINVAL;
+
+	fmt = v4l2_subdev_get_try_format(sd, state, format->pad);
+	if (!fmt)
+		return -EINVAL;
+
+	format->format = *fmt;
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(v4l2_subdev_get_fmt);
+
 #endif /* CONFIG_MEDIA_CONTROLLER */
 
 void v4l2_subdev_init(struct v4l2_subdev *sd, const struct v4l2_subdev_ops *ops)
diff --git a/include/media/v4l2-subdev.h b/include/media/v4l2-subdev.h
index 700ce376b22c..491bdbb1670c 100644
--- a/include/media/v4l2-subdev.h
+++ b/include/media/v4l2-subdev.h
@@ -1300,6 +1300,23 @@ v4l2_subdev_lock_and_get_active_state(struct v4l2_subdev *sd)
 	return sd->active_state;
 }
 
+/**
+ * v4l2_subdev_get_fmt() - Fill format based on state
+ * @sd: subdevice
+ * @state: subdevice state
+ * @format: pointer to &struct v4l2_subdev_format
+ *
+ * Fill @format->format field based on the information in the @format struct.
+ *
+ * This function can be used by the subdev drivers which support active state to
+ * implement v4l2_subdev_pad_ops.get_fmt if the subdev driver does not need to
+ * do anything special in their get_fmt op.
+ *
+ * Returns 0 on success, error value otherwise.
+ */
+int v4l2_subdev_get_fmt(struct v4l2_subdev *sd, struct v4l2_subdev_state *state,
+			struct v4l2_subdev_format *format);
+
 #endif /* CONFIG_MEDIA_CONTROLLER */
 
 /**
-- 
2.25.1