Make sure devices listed by a device's _DEP method are attached before

we attach the device itself.  The _DEP methode, introduced in ACPI 5.0,
is a hint that the device in question depends on OpRegion support from
the devices listed by _DEP, so we have to order them the proper way.
To prevent us from attaching those devices again when we encounter them
later walking down the device tree, keep track of our attempts to
attach a device driver to them using aflag in the aml_node structure.

ok guenther@

2 files changed, 37 insertions, 3 deletions

diff --git a/sys/dev/acpi/acpi.c b/sys/dev/acpi/acpi.c
index 736012413db..4828c0c6f47 100644
--- a/sys/dev/acpi/acpi.c
+++ b/sys/dev/acpi/acpi.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: acpi.c,v 1.310 2016/04/25 15:43:30 pirofti Exp $ */
+/* $OpenBSD: acpi.c,v 1.311 2016/05/08 10:09:25 kettenis Exp $ */
 /*
  * Copyright (c) 2005 Thorsten Lockert <tholo@sigmasoft.com>
  * Copyright (c) 2005 Jordan Hargrave <jordan@openbsd.org>
@@ -2772,6 +2772,33 @@ const char *acpi_skip_hids[] = {
 	NULL
 };
 
+void
+acpi_attach_deps(struct acpi_softc *sc, struct aml_node *node)
+{
+	struct aml_value res;
+	struct aml_node *dep;
+	int i;
+
+	if (aml_evalname(sc, node, "_DEP", 0, NULL, &res))
+		return;
+
+	if (res.type != AML_OBJTYPE_PACKAGE)
+		return;
+
+	for (i = 0; i < res.length; i++) {
+		if (res.v_package[i]->type != AML_OBJTYPE_STRING)
+			continue;
+		dep = aml_searchrel(node, res.v_package[i]->v_string);
+		if (dep == NULL || dep->attached)
+			continue;
+		dep = aml_searchname(dep, "_HID");
+		if (dep)
+			acpi_foundhid(dep, sc);
+	}
+
+	aml_freevalue(&res);
+}
+
 int
 acpi_foundhid(struct aml_node *node, void *arg)
 {
@@ -2794,6 +2821,8 @@ acpi_foundhid(struct aml_node *node, void *arg)
 	if ((sta & STA_PRESENT) == 0)
 		return (0);
 
+	acpi_attach_deps(sc, node->parent);
+
 	memset(&aaa, 0, sizeof(aaa));
 	aaa.aaa_iot = sc->sc_iot;
 	aaa.aaa_memt = sc->sc_memt;
@@ -2814,7 +2843,10 @@ acpi_foundhid(struct aml_node *node, void *arg)
 	}
 #endif
 
-	config_found(self, &aaa, acpi_print);
+	if (!node->parent->attached) {
+		config_found(self, &aaa, acpi_print);
+		node->parent->attached = 1;
+	}
 
 	return (0);
 }
diff --git a/sys/dev/acpi/amltypes.h b/sys/dev/acpi/amltypes.h
index 825b7671943..1f9bbedfa14 100644
--- a/sys/dev/acpi/amltypes.h
+++ b/sys/dev/acpi/amltypes.h
@@ -1,4 +1,4 @@
-/* $OpenBSD: amltypes.h,v 1.43 2016/04/02 00:34:47 jsg Exp $ */
+/* $OpenBSD: amltypes.h,v 1.44 2016/05/08 10:09:25 kettenis Exp $ */
 /*
  * Copyright (c) 2005 Jordan Hargrave <jordan@openbsd.org>
  *
@@ -376,6 +376,8 @@ struct aml_node {
 	SIMPLEQ_HEAD(,aml_node)	son;
 	SIMPLEQ_ENTRY(aml_node)	sib;
 
+	int		attached;
+
 	char		name[5];
 	u_int16_t	opcode;
 	u_int8_t	*start;