[PATCH v8 03/36] media: subdev: add 'which' to subdev state

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

The subdev state is passed to functions in the media drivers, and
usually either V4L2_SUBDEV_FORMAT_ACTIVE or V4L2_SUBDEV_FORMAT_TRY is
also given to the function in one way or another.

One op where this is not the case is v4l2_subdev_pad_ops.init_cfg. One
could argue that the initialization of the state should be the same for
both ACTIVE and TRY cases, but unfortunately that is not the case:

- Some drivers do also other things than just touch the state when
dealing with ACTIVE, e.g. if there is extra state outside the standard
subdev state.
- Some drivers might need to create, say, struct v4l2_subdev_format
which has 'which' field, and that needs to be filled with either ACTIVE
or TRY.

Currently init_cfg is only called for TRY case from the v4l2 framework,
passing the TRY state. Some drivers call their own init_cfg, passing
NULL as the state, which is used to indicate ACTIVE case.

In the future we want to pass subdev's active state from the v4l2
framework side, so we need a solution to this.

We could change the init_cfg() to include the TRY/ACTIVE value, which
would require changing more or less all the drivers. Instead, I have
added 'which' field to the subdev state itself, filled at state
allocation time, which only requires changes to the drivers that
allocate a state themselves.

Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
---
 drivers/media/platform/rcar-vin/rcar-v4l2.c |  2 +-
 drivers/media/platform/vsp1/vsp1_entity.c   |  2 +-
 drivers/media/v4l2-core/v4l2-subdev.c       | 10 +++++++---
 drivers/staging/media/tegra-video/vi.c      |  2 +-
 include/media/v4l2-subdev.h                 |  7 ++++++-
 5 files changed, 16 insertions(+), 7 deletions(-)

diff --git a/drivers/media/platform/rcar-vin/rcar-v4l2.c b/drivers/media/platform/rcar-vin/rcar-v4l2.c
index 5f4fa8c48f68..1de30d5b437f 100644
--- a/drivers/media/platform/rcar-vin/rcar-v4l2.c
+++ b/drivers/media/platform/rcar-vin/rcar-v4l2.c
@@ -252,7 +252,7 @@ static int rvin_try_format(struct rvin_dev *vin, u32 which,
 	u32 width, height;
 	int ret;
 
-	sd_state = v4l2_alloc_subdev_state(sd);
+	sd_state = v4l2_alloc_subdev_state(sd, V4L2_SUBDEV_FORMAT_ACTIVE);
 	if (IS_ERR(sd_state))
 		return PTR_ERR(sd_state);
 
diff --git a/drivers/media/platform/vsp1/vsp1_entity.c b/drivers/media/platform/vsp1/vsp1_entity.c
index e40bca254b8b..63ea5e472c33 100644
--- a/drivers/media/platform/vsp1/vsp1_entity.c
+++ b/drivers/media/platform/vsp1/vsp1_entity.c
@@ -675,7 +675,7 @@ int vsp1_entity_init(struct vsp1_device *vsp1, struct vsp1_entity *entity,
 	 * Allocate the pad configuration to store formats and selection
 	 * rectangles.
 	 */
-	entity->config = v4l2_alloc_subdev_state(&entity->subdev);
+	entity->config = v4l2_alloc_subdev_state(&entity->subdev, V4L2_SUBDEV_FORMAT_ACTIVE);
 	if (IS_ERR(entity->config)) {
 		media_entity_cleanup(&entity->subdev.entity);
 		return PTR_ERR(entity->config);
diff --git a/drivers/media/v4l2-core/v4l2-subdev.c b/drivers/media/v4l2-core/v4l2-subdev.c
index e1a794f69815..04ad319fb150 100644
--- a/drivers/media/v4l2-core/v4l2-subdev.c
+++ b/drivers/media/v4l2-core/v4l2-subdev.c
@@ -28,7 +28,7 @@ static int subdev_fh_init(struct v4l2_subdev_fh *fh, struct v4l2_subdev *sd)
 {
 	struct v4l2_subdev_state *state;
 
-	state = v4l2_alloc_subdev_state(sd);
+	state = v4l2_alloc_subdev_state(sd, V4L2_SUBDEV_FORMAT_TRY);
 	if (IS_ERR(state))
 		return PTR_ERR(state);
 
@@ -870,7 +870,9 @@ int v4l2_subdev_link_validate(struct media_link *link)
 }
 EXPORT_SYMBOL_GPL(v4l2_subdev_link_validate);
 
-struct v4l2_subdev_state *v4l2_alloc_subdev_state(struct v4l2_subdev *sd)
+struct v4l2_subdev_state *
+v4l2_alloc_subdev_state(struct v4l2_subdev *sd,
+			enum v4l2_subdev_format_whence which)
 {
 	struct v4l2_subdev_state *state;
 	int ret;
@@ -879,6 +881,8 @@ struct v4l2_subdev_state *v4l2_alloc_subdev_state(struct v4l2_subdev *sd)
 	if (!state)
 		return ERR_PTR(-ENOMEM);
 
+	state->which = which;
+
 	if (sd->entity.num_pads) {
 		state->pads = kvmalloc_array(sd->entity.num_pads,
 					     sizeof(*state->pads),
@@ -948,7 +952,7 @@ int v4l2_subdev_alloc_state(struct v4l2_subdev *sd)
 {
 	struct v4l2_subdev_state *state;
 
-	state = v4l2_alloc_subdev_state(sd);
+	state = v4l2_alloc_subdev_state(sd, V4L2_SUBDEV_FORMAT_ACTIVE);
 	if (IS_ERR(state))
 		return PTR_ERR(state);
 
diff --git a/drivers/staging/media/tegra-video/vi.c b/drivers/staging/media/tegra-video/vi.c
index a94d19e2a67c..691f5e04b0a1 100644
--- a/drivers/staging/media/tegra-video/vi.c
+++ b/drivers/staging/media/tegra-video/vi.c
@@ -507,7 +507,7 @@ static int __tegra_channel_try_format(struct tegra_vi_channel *chan,
 	if (!subdev)
 		return -ENODEV;
 
-	sd_state = v4l2_alloc_subdev_state(subdev);
+	sd_state = v4l2_alloc_subdev_state(subdev, V4L2_SUBDEV_FORMAT_ACTIVE);
 	if (IS_ERR(sd_state))
 		return PTR_ERR(sd_state);
 	/*
diff --git a/include/media/v4l2-subdev.h b/include/media/v4l2-subdev.h
index ecaf040ead57..5ec78ffda4f5 100644
--- a/include/media/v4l2-subdev.h
+++ b/include/media/v4l2-subdev.h
@@ -655,6 +655,7 @@ struct v4l2_subdev_pad_config {
 /**
  * struct v4l2_subdev_state - Used for storing subdev state information.
  *
+ * @which: state type (from enum v4l2_subdev_format_whence)
  * @pads: &struct v4l2_subdev_pad_config array
  *
  * This structure only needs to be passed to the pad op if the 'which' field
@@ -662,6 +663,7 @@ struct v4l2_subdev_pad_config {
  * %V4L2_SUBDEV_FORMAT_ACTIVE it is safe to pass %NULL.
  */
 struct v4l2_subdev_state {
+	u32 which;
 	struct v4l2_subdev_pad_config *pads;
 };
 
@@ -1141,10 +1143,13 @@ int v4l2_subdev_link_validate(struct media_link *link);
  * v4l2_alloc_subdev_state - allocate v4l2_subdev_state
  *
  * @sd: pointer to &struct v4l2_subdev for which the state is being allocated.
+ * @which: configuration type for the state (from enum v4l2_subdev_format_whence)
  *
  * Must call v4l2_free_subdev_state() when state is no longer needed.
  */
-struct v4l2_subdev_state *v4l2_alloc_subdev_state(struct v4l2_subdev *sd);
+struct v4l2_subdev_state *
+v4l2_alloc_subdev_state(struct v4l2_subdev *sd,
+			enum v4l2_subdev_format_whence which);
 
 /**
  * v4l2_free_subdev_state - free a v4l2_subdev_state
-- 
2.25.1