Attach acpi_perf early. Especially when it is being used to provide info

to other devices, it needs to be attached first.  (Multi-pass newbus
probes would be a better solution.)

1 files changed, 6 insertions, 1 deletions

diff --git a/sys/dev/acpica/acpi_perf.c b/sys/dev/acpica/acpi_perf.c
index 629f036434b0..0fc67ca71c3a 100644
--- a/sys/dev/acpica/acpi_perf.c
+++ b/sys/dev/acpica/acpi_perf.c
@@ -141,6 +141,7 @@ static void
 acpi_perf_identify(driver_t *driver, device_t parent)
 {
 	ACPI_HANDLE handle;
+	device_t dev;
 
 	/* Make sure we're not being doubly invoked. */
 	if (device_find_child(parent, "acpi_perf", -1) != NULL)
@@ -156,8 +157,12 @@ acpi_perf_identify(driver_t *driver, device_t parent)
 	/*
 	 * Add a child to every CPU that has the right methods.  In future
 	 * versions of the ACPI spec, CPUs can have different settings.
+	 * We probe this child now so that other devices that depend
+	 * on it (i.e., for info about supported states) will see it.
 	 */
-	if (BUS_ADD_CHILD(parent, 0, "acpi_perf", -1) == NULL)
+	if ((dev = BUS_ADD_CHILD(parent, 0, "acpi_perf", -1)) != NULL)
+		device_probe_and_attach(dev);
+	else
 		device_printf(parent, "add acpi_perf child failed\n");
 }