// SPDX-License-Identifier: GPL-2.0-only
/*
* ACPI support for platform bus type.
*
* Copyright (C) 2012, Intel Corporation
* Authors: Mika Westerberg <[email protected]>
* Mathias Nyman <[email protected]>
* Rafael J. Wysocki <[email protected]>
*/
#include <linux/acpi.h>
#include <linux/bits.h>
#include <linux/device.h>
#include <linux/err.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/dma-mapping.h>
#include <linux/pci.h>
#include <linux/platform_device.h>
#include "internal.h"
/* Exclude devices that have no _CRS resources provided */
#define ACPI_ALLOW_WO_RESOURCES BIT(0)
static const struct acpi_device_id forbidden_id_list[] = {
{"ACPI0009", 0}, /* IOxAPIC */
{"ACPI000A", 0}, /* IOAPIC */
{"PNP0000", 0}, /* PIC */
{"PNP0100", 0}, /* Timer */
{"PNP0200", 0}, /* AT DMA Controller */
{ACPI_SMBUS_MS_HID, ACPI_ALLOW_WO_RESOURCES}, /* ACPI SMBUS virtual device */
{ }
};
static struct platform_device *acpi_platform_device_find_by_companion(struct acpi_device *adev)
{
struct device *dev;
dev = bus_find_device_by_acpi_dev(&platform_bus_type, adev);
return dev ? to_platform_device(dev) : NULL;
}
static int acpi_platform_device_remove_notify(struct notifier_block *nb,
unsigned long value, void *arg)
{
struct acpi_device *adev = arg;
struct platform_device *pdev;
switch (value) {
case ACPI_RECONFIG_DEVICE_ADD:
/* Nothing to do here */
break;
case ACPI_RECONFIG_DEVICE_REMOVE:
if (!acpi_device_enumerated(adev))
break;
pdev = acpi_platform_device_find_by_companion(adev);
if (!pdev)
break;
platform_device_unregister(pdev);
put_device(&pdev->dev);
break;
}
return NOTIFY_OK;
}
static struct notifier_block acpi_platform_notifier = {
.notifier_call = acpi_platform_device_remove_notify,
};
static void acpi_platform_fill_resource(struct acpi_device *adev,
const struct resource *src, struct resource *dest)
{
struct device *parent;
*dest = *src;
/*
* If the device has parent we need to take its resources into
* account as well because this device might consume part of those.
*/
parent = acpi_get_first_physical_node(acpi_dev_parent(adev));
if (parent && dev_is_pci(parent))
dest->parent = pci_find_resource(to_pci_dev(parent), dest);
}
static unsigned int acpi_platform_resource_count(struct acpi_resource *ares, void *data)
{
bool *has_resources = data;
*has_resources = true;
return AE_CTRL_TERMINATE;
}
/**
* acpi_create_platform_device - Create platform device for ACPI device node
* @adev: ACPI device node to create a platform device for.
* @properties: Optional collection of build-in properties.
*
* Check if the given @adev can be represented as a platform device and, if
* that's the case, create and register a platform device, populate its common
* resources and returns a pointer to it. Otherwise, return %NULL.
*
* Name of the platform device will be the same as @adev's.
*/
struct platform_device *acpi_create_platform_device(struct acpi_device *adev,
const struct property_entry *properties)
{
struct acpi_device *parent = acpi_dev_parent(adev);
struct platform_device *pdev = NULL;
struct platform_device_info pdevinfo;
const struct acpi_device_id *match;
struct resource_entry *rentry;
struct list_head resource_list;
struct resource *resources = NULL;
int count;
/* If the ACPI node already has a physical device attached, skip it. */
if (adev->physical_node_count)
return NULL;
match = acpi_match_acpi_device(forbidden_id_list, adev);
if (match) {
if (match->driver_data & ACPI_ALLOW_WO_RESOURCES) {
bool has_resources = false;
acpi_walk_resources(adev->handle, METHOD_NAME__CRS,
acpi_platform_resource_count, &has_resources);
if (has_resources)
return ERR_PTR(-EINVAL);
} else {
return ERR_PTR(-EINVAL);
}
}
INIT_LIST_HEAD(&resource_list);
count = acpi_dev_get_resources(adev, &resource_list, NULL, NULL);
if (count < 0)
return NULL;
if (count > 0) {
resources = kcalloc(count, sizeof(*resources), GFP_KERNEL);
if (!resources) {
acpi_dev_free_resource_list(&resource_list);
return ERR_PTR(-ENOMEM);
}
count = 0;
list_for_each_entry(rentry, &resource_list, node)
acpi_platform_fill_resource(adev, rentry->res,
&resources[count++]);
acpi_dev_free_resource_list(&resource_list);
}
memset(&pdevinfo, 0, sizeof(pdevinfo));
/*
* If the ACPI node has a parent and that parent has a physical device
* attached to it, that physical device should be the parent of the
* platform device we are about to create.
*/
pdevinfo.parent = parent ? acpi_get_first_physical_node(parent) : NULL;
pdevinfo.name = dev_name(&adev->dev);
pdevinfo.id = PLATFORM_DEVID_NONE;
pdevinfo.res = resources;
pdevinfo.num_res = count;
pdevinfo.fwnode = acpi_fwnode_handle(adev);
pdevinfo.properties = properties;
if (acpi_dma_supported(adev))
pdevinfo.dma_mask = DMA_BIT_MASK(32);
else
pdevinfo.dma_mask = 0;
pdev = platform_device_register_full(&pdevinfo);
if (IS_ERR(pdev))
dev_err(&adev->dev, "platform device creation failed: %ld\n",
PTR_ERR(pdev));
else {
set_dev_node(&pdev->dev, acpi_get_node(adev->handle));
dev_dbg(&adev->dev, "created platform device %s\n",
dev_name(&pdev->dev));
}
kfree(resources);
return pdev;
}
EXPORT_SYMBOL_GPL(acpi_create_platform_device);
void __init acpi_platform_init(void)
{
acpi_reconfig_notifier_register(&acpi_platform_notifier);
}
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