1 files changed, 414 insertions, 0 deletions
diff --git a/drivers/acpi/glue.c b/drivers/acpi/glue.c
new file mode 100644
index 000000000..a194f3087
--- /dev/null
+++ b/drivers/acpi/glue.c
@@ -0,0 +1,414 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Link physical devices with ACPI devices support
+ *
+ * Copyright (c) 2005 David Shaohua Li <shaohua.li@intel.com>
+ * Copyright (c) 2005 Intel Corp.
+ */
+
+#define pr_fmt(fmt) "ACPI: " fmt
+
+#include <linux/acpi_iort.h>
+#include <linux/export.h>
+#include <linux/init.h>
+#include <linux/list.h>
+#include <linux/device.h>
+#include <linux/slab.h>
+#include <linux/rwsem.h>
+#include <linux/acpi.h>
+#include <linux/dma-mapping.h>
+#include <linux/pci.h>
+#include <linux/pci-acpi.h>
+#include <linux/platform_device.h>
+
+#include "internal.h"
+
+static LIST_HEAD(bus_type_list);
+static DECLARE_RWSEM(bus_type_sem);
+
+#define PHYSICAL_NODE_STRING "physical_node"
+#define PHYSICAL_NODE_NAME_SIZE (sizeof(PHYSICAL_NODE_STRING) + 10)
+
+int register_acpi_bus_type(struct acpi_bus_type *type)
+{
+	if (acpi_disabled)
+		return -ENODEV;
+	if (type && type->match && type->find_companion) {
+		down_write(&bus_type_sem);
+		list_add_tail(&type->list, &bus_type_list);
+		up_write(&bus_type_sem);
+		pr_info("bus type %s registered\n", type->name);
+		return 0;
+	}
+	return -ENODEV;
+}
+EXPORT_SYMBOL_GPL(register_acpi_bus_type);
+
+int unregister_acpi_bus_type(struct acpi_bus_type *type)
+{
+	if (acpi_disabled)
+		return 0;
+	if (type) {
+		down_write(&bus_type_sem);
+		list_del_init(&type->list);
+		up_write(&bus_type_sem);
+		pr_info("bus type %s unregistered\n", type->name);
+		return 0;
+	}
+	return -ENODEV;
+}
+EXPORT_SYMBOL_GPL(unregister_acpi_bus_type);
+
+static struct acpi_bus_type *acpi_get_bus_type(struct device *dev)
+{
+	struct acpi_bus_type *tmp, *ret = NULL;
+
+	down_read(&bus_type_sem);
+	list_for_each_entry(tmp, &bus_type_list, list) {
+		if (tmp->match(dev)) {
+			ret = tmp;
+			break;
+		}
+	}
+	up_read(&bus_type_sem);
+	return ret;
+}
+
+#define FIND_CHILD_MIN_SCORE	1
+#define FIND_CHILD_MID_SCORE	2
+#define FIND_CHILD_MAX_SCORE	3
+
+static int match_any(struct acpi_device *adev, void *not_used)
+{
+	return 1;
+}
+
+static bool acpi_dev_has_children(struct acpi_device *adev)
+{
+	return acpi_dev_for_each_child(adev, match_any, NULL) > 0;
+}
+
+static int find_child_checks(struct acpi_device *adev, bool check_children)
+{
+	unsigned long long sta;
+	acpi_status status;
+
+	if (check_children && !acpi_dev_has_children(adev))
+		return -ENODEV;
+
+	status = acpi_evaluate_integer(adev->handle, "_STA", NULL, &sta);
+	if (status == AE_NOT_FOUND) {
+		/*
+		 * Special case: backlight device objects without _STA are
+		 * preferred to other objects with the same _ADR value, because
+		 * it is more likely that they are actually useful.
+		 */
+		if (adev->pnp.type.backlight)
+			return FIND_CHILD_MID_SCORE;
+
+		return FIND_CHILD_MIN_SCORE;
+	}
+
+	if (ACPI_FAILURE(status) || !(sta & ACPI_STA_DEVICE_ENABLED))
+		return -ENODEV;
+
+	/*
+	 * If the device has a _HID returning a valid ACPI/PNP device ID, it is
+	 * better to make it look less attractive here, so that the other device
+	 * with the same _ADR value (that may not have a valid device ID) can be
+	 * matched going forward.  [This means a second spec violation in a row,
+	 * so whatever we do here is best effort anyway.]
+	 */
+	if (adev->pnp.type.platform_id)
+		return FIND_CHILD_MIN_SCORE;
+
+	return FIND_CHILD_MAX_SCORE;
+}
+
+struct find_child_walk_data {
+	struct acpi_device *adev;
+	u64 address;
+	int score;
+	bool check_sta;
+	bool check_children;
+};
+
+static int check_one_child(struct acpi_device *adev, void *data)
+{
+	struct find_child_walk_data *wd = data;
+	int score;
+
+	if (!adev->pnp.type.bus_address || acpi_device_adr(adev) != wd->address)
+		return 0;
+
+	if (!wd->adev) {
+		/*
+		 * This is the first matching object, so save it.  If it is not
+		 * necessary to look for any other matching objects, stop the
+		 * search.
+		 */
+		wd->adev = adev;
+		return !(wd->check_sta || wd->check_children);
+	}
+
+	/*
+	 * There is more than one matching device object with the same _ADR
+	 * value.  That really is unexpected, so we are kind of beyond the scope
+	 * of the spec here.  We have to choose which one to return, though.
+	 *
+	 * First, get the score for the previously found object and terminate
+	 * the walk if it is maximum.
+	*/
+	if (!wd->score) {
+		score = find_child_checks(wd->adev, wd->check_children);
+		if (score == FIND_CHILD_MAX_SCORE)
+			return 1;
+
+		wd->score = score;
+	}
+	/*
+	 * Second, if the object that has just been found has a better score,
+	 * replace the previously found one with it and terminate the walk if
+	 * the new score is maximum.
+	 */
+	score = find_child_checks(adev, wd->check_children);
+	if (score > wd->score) {
+		wd->adev = adev;
+		if (score == FIND_CHILD_MAX_SCORE)
+			return 1;
+
+		wd->score = score;
+	}
+
+	/* Continue, because there may be better matches. */
+	return 0;
+}
+
+static struct acpi_device *acpi_find_child(struct acpi_device *parent,
+					   u64 address, bool check_children,
+					   bool check_sta)
+{
+	struct find_child_walk_data wd = {
+		.address = address,
+		.check_children = check_children,
+		.check_sta = check_sta,
+		.adev = NULL,
+		.score = 0,
+	};
+
+	if (parent)
+		acpi_dev_for_each_child(parent, check_one_child, &wd);
+
+	return wd.adev;
+}
+
+struct acpi_device *acpi_find_child_device(struct acpi_device *parent,
+					   u64 address, bool check_children)
+{
+	return acpi_find_child(parent, address, check_children, true);
+}
+EXPORT_SYMBOL_GPL(acpi_find_child_device);
+
+struct acpi_device *acpi_find_child_by_adr(struct acpi_device *adev,
+					   acpi_bus_address adr)
+{
+	return acpi_find_child(adev, adr, false, false);
+}
+EXPORT_SYMBOL_GPL(acpi_find_child_by_adr);
+
+static void acpi_physnode_link_name(char *buf, unsigned int node_id)
+{
+	if (node_id > 0)
+		snprintf(buf, PHYSICAL_NODE_NAME_SIZE,
+			 PHYSICAL_NODE_STRING "%u", node_id);
+	else
+		strcpy(buf, PHYSICAL_NODE_STRING);
+}
+
+int acpi_bind_one(struct device *dev, struct acpi_device *acpi_dev)
+{
+	struct acpi_device_physical_node *physical_node, *pn;
+	char physical_node_name[PHYSICAL_NODE_NAME_SIZE];
+	struct list_head *physnode_list;
+	unsigned int node_id;
+	int retval = -EINVAL;
+
+	if (has_acpi_companion(dev)) {
+		if (acpi_dev) {
+			dev_warn(dev, "ACPI companion already set\n");
+			return -EINVAL;
+		} else {
+			acpi_dev = ACPI_COMPANION(dev);
+		}
+	}
+	if (!acpi_dev)
+		return -EINVAL;
+
+	acpi_dev_get(acpi_dev);
+	get_device(dev);
+	physical_node = kzalloc(sizeof(*physical_node), GFP_KERNEL);
+	if (!physical_node) {
+		retval = -ENOMEM;
+		goto err;
+	}
+
+	mutex_lock(&acpi_dev->physical_node_lock);
+
+	/*
+	 * Keep the list sorted by node_id so that the IDs of removed nodes can
+	 * be recycled easily.
+	 */
+	physnode_list = &acpi_dev->physical_node_list;
+	node_id = 0;
+	list_for_each_entry(pn, &acpi_dev->physical_node_list, node) {
+		/* Sanity check. */
+		if (pn->dev == dev) {
+			mutex_unlock(&acpi_dev->physical_node_lock);
+
+			dev_warn(dev, "Already associated with ACPI node\n");
+			kfree(physical_node);
+			if (ACPI_COMPANION(dev) != acpi_dev)
+				goto err;
+
+			put_device(dev);
+			acpi_dev_put(acpi_dev);
+			return 0;
+		}
+		if (pn->node_id == node_id) {
+			physnode_list = &pn->node;
+			node_id++;
+		}
+	}
+
+	physical_node->node_id = node_id;
+	physical_node->dev = dev;
+	list_add(&physical_node->node, physnode_list);
+	acpi_dev->physical_node_count++;
+
+	if (!has_acpi_companion(dev))
+		ACPI_COMPANION_SET(dev, acpi_dev);
+
+	acpi_physnode_link_name(physical_node_name, node_id);
+	retval = sysfs_create_link(&acpi_dev->dev.kobj, &dev->kobj,
+				   physical_node_name);
+	if (retval)
+		dev_err(&acpi_dev->dev, "Failed to create link %s (%d)\n",
+			physical_node_name, retval);
+
+	retval = sysfs_create_link(&dev->kobj, &acpi_dev->dev.kobj,
+				   "firmware_node");
+	if (retval)
+		dev_err(dev, "Failed to create link firmware_node (%d)\n",
+			retval);
+
+	mutex_unlock(&acpi_dev->physical_node_lock);
+
+	if (acpi_dev->wakeup.flags.valid)
+		device_set_wakeup_capable(dev, true);
+
+	return 0;
+
+ err:
+	ACPI_COMPANION_SET(dev, NULL);
+	put_device(dev);
+	acpi_dev_put(acpi_dev);
+	return retval;
+}
+EXPORT_SYMBOL_GPL(acpi_bind_one);
+
+int acpi_unbind_one(struct device *dev)
+{
+	struct acpi_device *acpi_dev = ACPI_COMPANION(dev);
+	struct acpi_device_physical_node *entry;
+
+	if (!acpi_dev)
+		return 0;
+
+	mutex_lock(&acpi_dev->physical_node_lock);
+
+	list_for_each_entry(entry, &acpi_dev->physical_node_list, node)
+		if (entry->dev == dev) {
+			char physnode_name[PHYSICAL_NODE_NAME_SIZE];
+
+			list_del(&entry->node);
+			acpi_dev->physical_node_count--;
+
+			acpi_physnode_link_name(physnode_name, entry->node_id);
+			sysfs_remove_link(&acpi_dev->dev.kobj, physnode_name);
+			sysfs_remove_link(&dev->kobj, "firmware_node");
+			ACPI_COMPANION_SET(dev, NULL);
+			/* Drop references taken by acpi_bind_one(). */
+			put_device(dev);
+			acpi_dev_put(acpi_dev);
+			kfree(entry);
+			break;
+		}
+
+	mutex_unlock(&acpi_dev->physical_node_lock);
+	return 0;
+}
+EXPORT_SYMBOL_GPL(acpi_unbind_one);
+
+void acpi_device_notify(struct device *dev)
+{
+	struct acpi_device *adev;
+	int ret;
+
+	ret = acpi_bind_one(dev, NULL);
+	if (ret) {
+		struct acpi_bus_type *type = acpi_get_bus_type(dev);
+
+		if (!type)
+			goto err;
+
+		adev = type->find_companion(dev);
+		if (!adev) {
+			dev_dbg(dev, "ACPI companion not found\n");
+			goto err;
+		}
+		ret = acpi_bind_one(dev, adev);
+		if (ret)
+			goto err;
+
+		if (type->setup) {
+			type->setup(dev);
+			goto done;
+		}
+	} else {
+		adev = ACPI_COMPANION(dev);
+
+		if (dev_is_pci(dev)) {
+			pci_acpi_setup(dev, adev);
+			goto done;
+		} else if (dev_is_platform(dev)) {
+			acpi_configure_pmsi_domain(dev);
+		}
+	}
+
+	if (adev->handler && adev->handler->bind)
+		adev->handler->bind(dev);
+
+done:
+	acpi_handle_debug(ACPI_HANDLE(dev), "Bound to device %s\n",
+			  dev_name(dev));
+
+	return;
+
+err:
+	dev_dbg(dev, "No ACPI support\n");
+}
+
+void acpi_device_notify_remove(struct device *dev)
+{
+	struct acpi_device *adev = ACPI_COMPANION(dev);
+
+	if (!adev)
+		return;
+
+	if (dev_is_pci(dev))
+		pci_acpi_cleanup(dev, adev);
+	else if (adev->handler && adev->handler->unbind)
+		adev->handler->unbind(dev);
+
+	acpi_unbind_one(dev);
+}