diff options
Diffstat (limited to 'drivers/acpi/glue.c')
| -rw-r--r-- | drivers/acpi/glue.c | 376 |
1 files changed, 376 insertions, 0 deletions
diff --git a/drivers/acpi/glue.c b/drivers/acpi/glue.c new file mode 100644 index 000000000..36b24b065 --- /dev/null +++ b/drivers/acpi/glue.c @@ -0,0 +1,376 @@ +// 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. + */ + +#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/platform_device.h> + +#include "internal.h" + +#define ACPI_GLUE_DEBUG 0 +#if ACPI_GLUE_DEBUG +#define DBG(fmt, ...) \ + printk(KERN_DEBUG PREFIX fmt, ##__VA_ARGS__) +#else +#define DBG(fmt, ...) \ +do { \ + if (0) \ + printk(KERN_DEBUG PREFIX fmt, ##__VA_ARGS__); \ +} while (0) +#endif +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); + printk(KERN_INFO PREFIX "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); + printk(KERN_INFO PREFIX "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_MAX_SCORE 2 + +static int find_child_checks(struct acpi_device *adev, bool check_children) +{ + bool sta_present = true; + unsigned long long sta; + acpi_status status; + + status = acpi_evaluate_integer(adev->handle, "_STA", NULL, &sta); + if (status == AE_NOT_FOUND) + sta_present = false; + else if (ACPI_FAILURE(status) || !(sta & ACPI_STA_DEVICE_ENABLED)) + return -ENODEV; + + if (check_children && list_empty(&adev->children)) + 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.] + */ + return sta_present && !adev->pnp.type.platform_id ? + FIND_CHILD_MAX_SCORE : FIND_CHILD_MIN_SCORE; +} + +struct acpi_device *acpi_find_child_device(struct acpi_device *parent, + u64 address, bool check_children) +{ + struct acpi_device *adev, *ret = NULL; + int ret_score = 0; + + if (!parent) + return NULL; + + list_for_each_entry(adev, &parent->children, node) { + unsigned long long addr; + acpi_status status; + int score; + + status = acpi_evaluate_integer(adev->handle, METHOD_NAME__ADR, + NULL, &addr); + if (ACPI_FAILURE(status) || addr != address) + continue; + + if (!ret) { + /* This is the first matching object. Save it. */ + ret = adev; + continue; + } + /* + * 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, check if the previously found object is good enough + * and return it if so. Second, do the same for the object that + * we've just found. + */ + if (!ret_score) { + ret_score = find_child_checks(ret, check_children); + if (ret_score == FIND_CHILD_MAX_SCORE) + return ret; + } + score = find_child_checks(adev, check_children); + if (score == FIND_CHILD_MAX_SCORE) { + return adev; + } else if (score > ret_score) { + ret = adev; + ret_score = score; + } + } + return ret; +} +EXPORT_SYMBOL_GPL(acpi_find_child_device); + +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; + + get_device(&acpi_dev->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); + put_device(&acpi_dev->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); + put_device(&acpi_dev->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); + put_device(&acpi_dev->dev); + kfree(entry); + break; + } + + mutex_unlock(&acpi_dev->physical_node_lock); + return 0; +} +EXPORT_SYMBOL_GPL(acpi_unbind_one); + +static int acpi_device_notify(struct device *dev) +{ + struct acpi_bus_type *type = acpi_get_bus_type(dev); + struct acpi_device *adev; + int ret; + + ret = acpi_bind_one(dev, NULL); + if (ret && type) { + struct acpi_device *adev; + + adev = type->find_companion(dev); + if (!adev) { + DBG("Unable to get handle for %s\n", dev_name(dev)); + ret = -ENODEV; + goto out; + } + ret = acpi_bind_one(dev, adev); + if (ret) + goto out; + } + adev = ACPI_COMPANION(dev); + if (!adev) + goto out; + + if (dev_is_platform(dev)) + acpi_configure_pmsi_domain(dev); + + if (type && type->setup) + type->setup(dev); + else if (adev->handler && adev->handler->bind) + adev->handler->bind(dev); + + out: +#if ACPI_GLUE_DEBUG + if (!ret) { + struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; + + acpi_get_name(ACPI_HANDLE(dev), ACPI_FULL_PATHNAME, &buffer); + DBG("Device %s -> %s\n", dev_name(dev), (char *)buffer.pointer); + kfree(buffer.pointer); + } else + DBG("Device %s -> No ACPI support\n", dev_name(dev)); +#endif + + return ret; +} + +static int acpi_device_notify_remove(struct device *dev) +{ + struct acpi_device *adev = ACPI_COMPANION(dev); + struct acpi_bus_type *type; + + if (!adev) + return 0; + + type = acpi_get_bus_type(dev); + if (type && type->cleanup) + type->cleanup(dev); + else if (adev->handler && adev->handler->unbind) + adev->handler->unbind(dev); + + acpi_unbind_one(dev); + return 0; +} + +int acpi_platform_notify(struct device *dev, enum kobject_action action) +{ + switch (action) { + case KOBJ_ADD: + acpi_device_notify(dev); + break; + case KOBJ_REMOVE: + acpi_device_notify_remove(dev); + break; + default: + break; + } + return 0; +} |