init: add detection support to init structure

This lets a component have a detection routine.
This mimics the struct iommu_table_entry from the
kernel. For now we just add a detect routine to
the x thing.

Signed-off-by: Luis R. Rodriguez <mcgrof@kernel.org>

2 files changed, 11 insertions, 3 deletions

diff --git a/init.c b/init.c
index 5cebb87..5991252 100644
--- a/init.c
+++ b/init.c
@@ -6,7 +6,12 @@ static void init_x(void) {
 	sleep(1);
 }
 
+static int detect_x(void) {
+	return 1;
+}
+
 struct init_fn x_init_fn __init_fn(INIT_EARLY) = {
+	.detect = detect_x,
 	.initialise = init_x,
 	.name = "X thing",
 };
@@ -20,9 +25,11 @@ int init(void)
 	printf("Number of init entries: %d\n", num_inits);
 
 	for_each_table_entry (init_fn, INIT_FNS) {
-		printf("Initializing %s ...\n", init_fn->name);
-		init_fn->initialise();
-		printf("Completed initializing %s !\n", init_fn->name);
+		if (init_fn->detect && init_fn->detect() > 0) {
+			printf("Initializing %s ...\n", init_fn->name);
+			init_fn->initialise();
+			printf("Completed initializing %s !\n", init_fn->name);
+		}
 	}
 
 	return 0;
diff --git a/init.h b/init.h
index ccfd9d0..1ff5a11 100644
--- a/init.h
+++ b/init.h
@@ -7,6 +7,7 @@
  * call to init().
  */
 struct init_fn {                                                                
+	int (* detect)(void);
 	void (* initialise) (void);
 	const char *name;
 };