alistair23-linux/drivers/acpi/acpi_platform.c
Rafael J. Wysocki d2fe7251a3 ACPI / scan: Drop unnecessary label from acpi_create_platform_device()
The create_dev label in acpi_create_platform_device() is not
necessary, because the if statement causing the jump to it to
happen may be rearranged to avoid that jump.

Rework the code accordingly (no functional changes should result
drom that).

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-08-07 01:11:33 +02:00

131 lines
3.6 KiB
C

/*
* ACPI support for platform bus type.
*
* Copyright (C) 2012, Intel Corporation
* Authors: Mika Westerberg <mika.westerberg@linux.intel.com>
* Mathias Nyman <mathias.nyman@linux.intel.com>
* Rafael J. Wysocki <rafael.j.wysocki@intel.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/acpi.h>
#include <linux/device.h>
#include <linux/err.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include "internal.h"
ACPI_MODULE_NAME("platform");
/*
* The following ACPI IDs are known to be suitable for representing as
* platform devices.
*/
static const struct acpi_device_id acpi_platform_device_ids[] = {
{ "PNP0D40" },
{ }
};
/**
* acpi_create_platform_device - Create platform device for ACPI device node
* @adev: ACPI device node to create a platform device for.
* @id: ACPI device ID used to match @adev.
*
* 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.
*/
int acpi_create_platform_device(struct acpi_device *adev,
const struct acpi_device_id *id)
{
struct platform_device *pdev = NULL;
struct acpi_device *acpi_parent;
struct platform_device_info pdevinfo;
struct resource_list_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 0;
INIT_LIST_HEAD(&resource_list);
count = acpi_dev_get_resources(adev, &resource_list, NULL, NULL);
if (count < 0) {
return 0;
} else if (count > 0) {
resources = kmalloc(count * sizeof(struct resource),
GFP_KERNEL);
if (!resources) {
dev_err(&adev->dev, "No memory for resources\n");
acpi_dev_free_resource_list(&resource_list);
return -ENOMEM;
}
count = 0;
list_for_each_entry(rentry, &resource_list, node)
resources[count++] = rentry->res;
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 = NULL;
acpi_parent = adev->parent;
if (acpi_parent) {
struct acpi_device_physical_node *entry;
struct list_head *list;
mutex_lock(&acpi_parent->physical_node_lock);
list = &acpi_parent->physical_node_list;
if (!list_empty(list)) {
entry = list_first_entry(list,
struct acpi_device_physical_node,
node);
pdevinfo.parent = entry->dev;
}
mutex_unlock(&acpi_parent->physical_node_lock);
}
pdevinfo.name = dev_name(&adev->dev);
pdevinfo.id = -1;
pdevinfo.res = resources;
pdevinfo.num_res = count;
pdevinfo.acpi_node.handle = adev->handle;
pdev = platform_device_register_full(&pdevinfo);
if (IS_ERR(pdev)) {
dev_err(&adev->dev, "platform device creation failed: %ld\n",
PTR_ERR(pdev));
pdev = NULL;
} else {
dev_dbg(&adev->dev, "created platform device %s\n",
dev_name(&pdev->dev));
}
kfree(resources);
return 1;
}
static struct acpi_scan_handler platform_handler = {
.ids = acpi_platform_device_ids,
.attach = acpi_create_platform_device,
};
void __init acpi_platform_init(void)
{
acpi_scan_add_handler(&platform_handler);
}