linux-stable/drivers/acpi/container.c
Rafael J. Wysocki abda0af4cd ACPI: container: Use acpi_dev_for_each_child()
Instead of walking the list of children of an ACPI device directly,
use acpi_dev_for_each_child() to carry out an action for all of
the given ACPI device's children.

This will help to eliminate the children list head from struct
acpi_device as it is redundant and it is used in questionable ways
in some places (in particular, locking is needed for walking the
list pointed to it safely, but it is often missing).

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
2022-06-20 20:33:05 +02:00

118 lines
2.6 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* container.c - ACPI Generic Container Driver
*
* Copyright (C) 2004 Anil S Keshavamurthy (anil.s.keshavamurthy@intel.com)
* Copyright (C) 2004 Keiichiro Tokunaga (tokunaga.keiich@jp.fujitsu.com)
* Copyright (C) 2004 Motoyuki Ito (motoyuki@soft.fujitsu.com)
* Copyright (C) 2004 FUJITSU LIMITED
* Copyright (C) 2004, 2013 Intel Corp.
* Author: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
*/
#include <linux/acpi.h>
#include <linux/container.h>
#include "internal.h"
static const struct acpi_device_id container_device_ids[] = {
{"ACPI0004", 0},
{"PNP0A05", 0},
{"PNP0A06", 0},
{"", 0},
};
#ifdef CONFIG_ACPI_CONTAINER
static int check_offline(struct acpi_device *adev, void *not_used)
{
if (acpi_scan_is_offline(adev, false))
return 0;
return -EBUSY;
}
static int acpi_container_offline(struct container_dev *cdev)
{
/* Check all of the dependent devices' physical companions. */
return acpi_dev_for_each_child(ACPI_COMPANION(&cdev->dev), check_offline, NULL);
}
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)
{
struct container_dev *cdev;
struct device *dev;
int ret;
if (adev->flags.is_dock_station)
return 0;
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) {
put_device(dev);
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 void container_device_online(struct acpi_device *adev)
{
struct device *dev = acpi_driver_data(adev);
kobject_uevent(&dev->kobj, KOBJ_ONLINE);
}
static struct acpi_scan_handler container_handler = {
.ids = container_device_ids,
.attach = container_device_attach,
.detach = container_device_detach,
.hotplug = {
.enabled = true,
.demand_offline = true,
.notify_online = container_device_online,
},
};
void __init acpi_container_init(void)
{
acpi_scan_add_handler(&container_handler);
}
#else
static struct acpi_scan_handler container_handler = {
.ids = container_device_ids,
};
void __init acpi_container_init(void)
{
acpi_scan_add_handler_with_hotplug(&container_handler, "container");
}
#endif /* CONFIG_ACPI_CONTAINER */