Merge tag 'efi-urgent' into x86/urgent

 * Avoid WARN_ON() when mapping BGRT on Baytrail (EFI 32-bit).

Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>

1 files changed, 50 insertions, 5 deletions

diff --git a/drivers/acpi/container.c b/drivers/acpi/container.c
index e23151667655..0b6ae6eb5c4a 100644
--- a/drivers/acpi/container.c
+++ b/drivers/acpi/container.c
@@ -27,8 +27,7 @@
  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  */
 #include <linux/acpi.h>
-
-#include "internal.h"
+#include <linux/container.h>
 
 #include "internal.h"
 
@@ -44,19 +43,65 @@ static const struct acpi_device_id container_device_ids[] = {
 	{"", 0},
 };
 
-static int container_device_attach(struct acpi_device *device,
+static int acpi_container_offline(struct container_dev *cdev)
+{
+	struct acpi_device *adev = ACPI_COMPANION(&cdev->dev);
+	struct acpi_device *child;
+
+	/* Check all of the dependent devices' physical companions. */
+	list_for_each_entry(child, &adev->children, node)
+		if (!acpi_scan_is_offline(child, false))
+			return -EBUSY;
+
+	return 0;
+}
+
+static void acpi_container_release(struct device *dev)
+{
+	kfree(to_container_dev(dev));
+}
+
+static int container_device_attach(struct acpi_device *adev,
 				   const struct acpi_device_id *not_used)
 {
-	/* This is necessary for container hotplug to work. */
+	struct container_dev *cdev;
+	struct device *dev;
+	int ret;
+
+	cdev = kzalloc(sizeof(*cdev), GFP_KERNEL);
+	if (!cdev)
+		return -ENOMEM;
+
+	cdev->offline = acpi_container_offline;
+	dev = &cdev->dev;
+	dev->bus = &container_subsys;
+	dev_set_name(dev, "%s", dev_name(&adev->dev));
+	ACPI_COMPANION_SET(dev, adev);
+	dev->release = acpi_container_release;
+	ret = device_register(dev);
+	if (ret)
+		return ret;
+
+	adev->driver_data = dev;
 	return 1;
 }
 
+static void container_device_detach(struct acpi_device *adev)
+{
+	struct device *dev = acpi_driver_data(adev);
+
+	adev->driver_data = NULL;
+	if (dev)
+		device_unregister(dev);
+}
+
 static struct acpi_scan_handler container_handler = {
 	.ids = container_device_ids,
 	.attach = container_device_attach,
+	.detach = container_device_detach,
 	.hotplug = {
 		.enabled = true,
-		.mode = AHM_CONTAINER,
+		.demand_offline = true,
 	},
 };