media: v4l: async: Make V4L2 async match information a struct

Make V4L2 async match information a struct, making it easier to use it
elsewhere outside the scope of struct v4l2_async_subdev.

Also remove an obsolete comment --- none of these fields are supposed to
be touched by drivers.
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Tested-by: Philipp Zabel <p.zabel@pengutronix.de> # imx6qp
Tested-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> # rcar + adv746x
Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Tested-by: Aishwarya Kothari <aishwarya.kothari@toradex.com> # Apalis i.MX6Q with TC358743
Tested-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com> # Renesas RZ/G2L SMARC
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>

drivers/media/v4l2-core/v4l2-async.c

@@ -212,7 +212,7 @@ v4l2_async_find_match(struct v4l2_async_notifier *notifier,
 
 	list_for_each_entry(asd, &notifier->waiting, list) {
 		/* bus_type has been verified valid before */
-		switch (asd->match_type) {
+		switch (asd->match.type) {
 		case V4L2_ASYNC_MATCH_I2C:
 			match = match_i2c;
 			break;
@@ -237,10 +237,10 @@ v4l2_async_find_match(struct v4l2_async_notifier *notifier,
 static bool asd_equal(struct v4l2_async_subdev *asd_x,
 		      struct v4l2_async_subdev *asd_y)
 {
-	if (asd_x->match_type != asd_y->match_type)
+	if (asd_x->match.type != asd_y->match.type)
 		return false;
 
-	switch (asd_x->match_type) {
+	switch (asd_x->match.type) {
 	case V4L2_ASYNC_MATCH_I2C:
 		return asd_x->match.i2c.adapter_id ==
 			asd_y->match.i2c.adapter_id &&
@@ -554,7 +554,7 @@ static int v4l2_async_nf_asd_valid(struct v4l2_async_notifier *notifier,
 {
 	struct device *dev = notifier_dev(notifier);
 
-	switch (asd->match_type) {
+	switch (asd->match.type) {
 	case V4L2_ASYNC_MATCH_I2C:
 	case V4L2_ASYNC_MATCH_FWNODE:
 		if (v4l2_async_nf_has_async_subdev(notifier, asd, skip_self)) {
@@ -564,7 +564,7 @@ static int v4l2_async_nf_asd_valid(struct v4l2_async_notifier *notifier,
 		break;
 	default:
 		dev_err(dev, "v4l2-async: Invalid match type %u on %p\n",
-			asd->match_type, asd);
+			asd->match.type, asd);
 		return -EINVAL;
 	}
 
@@ -690,7 +690,7 @@ static void __v4l2_async_nf_cleanup(struct v4l2_async_notifier *notifier)
 		return;
 
 	list_for_each_entry_safe(asd, tmp, &notifier->asd_list, asd_list) {
-		switch (asd->match_type) {
+		switch (asd->match.type) {
 		case V4L2_ASYNC_MATCH_FWNODE:
 			fwnode_handle_put(asd->match.fwnode);
 			break;
@@ -745,7 +745,7 @@ __v4l2_async_nf_add_fwnode(struct v4l2_async_notifier *notifier,
 	if (!asd)
 		return ERR_PTR(-ENOMEM);
 
-	asd->match_type = V4L2_ASYNC_MATCH_FWNODE;
+	asd->match.type = V4L2_ASYNC_MATCH_FWNODE;
 	asd->match.fwnode = fwnode_handle_get(fwnode);
 
 	ret = __v4l2_async_nf_add_subdev(notifier, asd);
@@ -792,7 +792,7 @@ __v4l2_async_nf_add_i2c(struct v4l2_async_notifier *notifier, int adapter_id,
 	if (!asd)
 		return ERR_PTR(-ENOMEM);
 
-	asd->match_type = V4L2_ASYNC_MATCH_I2C;
+	asd->match.type = V4L2_ASYNC_MATCH_I2C;
 	asd->match.i2c.adapter_id = adapter_id;
 	asd->match.i2c.address = address;
 
@@ -905,7 +905,7 @@ EXPORT_SYMBOL(v4l2_async_unregister_subdev);
 static void print_waiting_subdev(struct seq_file *s,
 				 struct v4l2_async_subdev *asd)
 {
-	switch (asd->match_type) {
+	switch (asd->match.type) {
 	case V4L2_ASYNC_MATCH_I2C:
 		seq_printf(s, " [i2c] dev=%d-%04x\n", asd->match.i2c.adapter_id,
 			   asd->match.i2c.address);

include/media/v4l2-async.h

@@ -34,23 +34,37 @@ enum v4l2_async_match_type {
 };
 
 /**
- * struct v4l2_async_subdev - sub-device descriptor, as known to a bridge
+ * struct v4l2_async_match_desc - async sub-device match information
  *
- * @match_type:	type of match that will be used
- * @match:	union of per-bus type matching data sets
- * @match.fwnode:
- *		pointer to &struct fwnode_handle to be matched.
+ * @type:	type of match that will be used
+ * @fwnode:	pointer to &struct fwnode_handle to be matched.
  *		Used if @match_type is %V4L2_ASYNC_MATCH_FWNODE.
- * @match.i2c:	embedded struct with I2C parameters to be matched.
+ * @i2c:	embedded struct with I2C parameters to be matched.
  *		Both @match.i2c.adapter_id and @match.i2c.address
  *		should be matched.
  *		Used if @match_type is %V4L2_ASYNC_MATCH_I2C.
- * @match.i2c.adapter_id:
+ * @i2c.adapter_id:
  *		I2C adapter ID to be matched.
  *		Used if @match_type is %V4L2_ASYNC_MATCH_I2C.
- * @match.i2c.address:
+ * @i2c.address:
  *		I2C address to be matched.
  *		Used if @match_type is %V4L2_ASYNC_MATCH_I2C.
+ */
+struct v4l2_async_match_desc {
+	enum v4l2_async_match_type type;
+	union {
+		struct fwnode_handle *fwnode;
+		struct {
+			int adapter_id;
+			unsigned short address;
+		} i2c;
+	};
+};
+
+/**
+ * struct v4l2_async_subdev - sub-device descriptor, as known to a bridge
+ *
+ * @match:	struct of match type and per-bus type matching data sets
  * @asd_list:	used to add struct v4l2_async_subdev objects to the
  *		master notifier @asd_list
  * @list:	used to link struct v4l2_async_subdev objects, waiting to be
@@ -61,16 +75,7 @@ enum v4l2_async_match_type {
  * v4l2_async_subdev as its first member.
  */
 struct v4l2_async_subdev {
-	enum v4l2_async_match_type match_type;
-	union {
-		struct fwnode_handle *fwnode;
-		struct {
-			int adapter_id;
-			unsigned short address;
-		} i2c;
-	} match;
-
-	/* v4l2-async core private: not to be used by drivers */
+	struct v4l2_async_match_desc match;
 	struct list_head list;
 	struct list_head asd_list;
 };