[PATCH v3 07/29] media: v4l2-subdev: Add frame descriptor passthrough for CSI-2 and DVP

[Sakari Ailus <sakari.ailus@linux.intel.com>]

Add frame descriptor pass-through functions specific to MIPI CSI-2 and DVP
(parallel) interfaces. The two new functions are needed in order to
support frame descriptor-less sub-device drivers.

Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
---
 drivers/media/v4l2-core/v4l2-subdev.c | 20 +++++++++++
 include/media/v4l2-subdev.h           | 49 +++++++++++++++++++++++++++
 2 files changed, 69 insertions(+)

diff --git a/drivers/media/v4l2-core/v4l2-subdev.c b/drivers/media/v4l2-core/v4l2-subdev.c
index 071657459202..f5fa62038754 100644
--- a/drivers/media/v4l2-core/v4l2-subdev.c
+++ b/drivers/media/v4l2-core/v4l2-subdev.c
@@ -2672,6 +2672,26 @@ int v4l2_subdev_get_frame_desc_passthrough(struct v4l2_subdev *sd,
 }
 EXPORT_SYMBOL_GPL(v4l2_subdev_get_frame_desc_passthrough);
 
+int v4l2_subdev_get_frame_desc_passthrough_dvp(struct v4l2_subdev *sd,
+					       unsigned int pad,
+					       struct v4l2_mbus_frame_desc *fd)
+{
+	fd->type = V4L2_MBUS_FRAME_DESC_TYPE_PARALLEL;
+
+	return v4l2_subdev_get_frame_desc_passthrough(sd, pad, fd);
+}
+EXPORT_SYMBOL_GPL(v4l2_subdev_get_frame_desc_passthrough_dvp);
+
+int v4l2_subdev_get_frame_desc_passthrough_csi2(struct v4l2_subdev *sd,
+						unsigned int pad,
+						struct v4l2_mbus_frame_desc *fd)
+{
+	fd->type = V4L2_MBUS_FRAME_DESC_TYPE_CSI2;
+
+	return v4l2_subdev_get_frame_desc_passthrough(sd, pad, fd);
+}
+EXPORT_SYMBOL_GPL(v4l2_subdev_get_frame_desc_passthrough_csi2);
+
 struct v4l2_mbus_frame_desc *
 v4l2_subdev_get_frame_desc(struct v4l2_subdev *sd, unsigned int pad,
 			   enum v4l2_mbus_frame_desc_type type)
diff --git a/include/media/v4l2-subdev.h b/include/media/v4l2-subdev.h
index daebf8982c43..80ae7649f5c7 100644
--- a/include/media/v4l2-subdev.h
+++ b/include/media/v4l2-subdev.h
@@ -1795,6 +1795,55 @@ int v4l2_subdev_get_frame_desc_passthrough(struct v4l2_subdev *sd,
 					   unsigned int pad,
 					   struct v4l2_mbus_frame_desc *fd);
 
+/**
+ * v4l2_subdev_get_frame_desc_passthrough_dvp() - Helper to implement the subdev
+ *	get_frame_desc operation in simple passthrough cases for DVP
+ * @sd: The subdevice
+ * @pad: The source pad index
+ * @fd: The mbus frame desc
+ *
+ * This function locks the subdevice's active state, calls
+ * __v4l2_subdev_get_frame_desc_passthrough(), and unlocks the state.
+ *
+ * This function can be assigned directly as the .get_frame_desc callback in
+ * &v4l2_subdev_pad_ops for subdevices that pass streams through without
+ * modification. Drivers that need to perform additional work should use
+ * __v4l2_subdev_get_frame_desc_passthrough() in their custom
+ * .get_frame_desc implementation instead.
+ *
+ * This callback can be used for the DVP (Digital Video Port), also often called
+ * simply the "parallel interface".
+ *
+ * Return: 0 on success, or a negative error code otherwise.
+ */
+int v4l2_subdev_get_frame_desc_passthrough_dvp(struct v4l2_subdev *sd,
+					       unsigned int pad,
+					       struct v4l2_mbus_frame_desc *fd);
+
+/**
+ * v4l2_subdev_get_frame_desc_passthrough_csi2() - Helper to implement the subdev
+ *	get_frame_desc operation in simple passthrough cases for MIPI CSI-2
+ * @sd: The subdevice
+ * @pad: The source pad index
+ * @fd: The mbus frame desc
+ *
+ * This function locks the subdevice's active state, calls
+ * __v4l2_subdev_get_frame_desc_passthrough(), and unlocks the state.
+ *
+ * This function can be assigned directly as the .get_frame_desc callback in
+ * &v4l2_subdev_pad_ops for subdevices that pass streams through without
+ * modification. Drivers that need to perform additional work should use
+ * __v4l2_subdev_get_frame_desc_passthrough() in their custom
+ * .get_frame_desc implementation instead.
+ *
+ * This callback can be used for the MIPI CSI-2 interface.
+ *
+ * Return: 0 on success, or a negative error code otherwise.
+ */
+int v4l2_subdev_get_frame_desc_passthrough_csi2(struct v4l2_subdev *sd,
+						unsigned int pad,
+						struct v4l2_mbus_frame_desc *fd);
+
 /**
  * v4l2_subdev_get_frame_desc() - Get a frame descriptor for a pad
  * @sd: The sub-device
-- 
2.47.3