linux/drivers/acpi/acpi_platform.c

165 lines
4.4 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");
/* Flags for acpi_create_platform_device */
#define ACPI_PLATFORM_CLK BIT(0)
/*
* 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" },
/* Haswell LPSS devices */
{ "INT33C0", ACPI_PLATFORM_CLK },
{ "INT33C1", ACPI_PLATFORM_CLK },
{ "INT33C2", ACPI_PLATFORM_CLK },
{ "INT33C3", ACPI_PLATFORM_CLK },
{ "INT33C4", ACPI_PLATFORM_CLK },
{ "INT33C5", ACPI_PLATFORM_CLK },
{ "INT33C6", ACPI_PLATFORM_CLK },
{ "INT33C7", ACPI_PLATFORM_CLK },
{ }
};
static int acpi_create_platform_clks(struct acpi_device *adev)
{
static struct platform_device *pdev;
/* Create Lynxpoint LPSS clocks */
if (!pdev && !strncmp(acpi_device_hid(adev), "INT33C", 6)) {
pdev = platform_device_register_simple("clk-lpt", -1, NULL, 0);
if (IS_ERR(pdev))
return PTR_ERR(pdev);
}
return 0;
}
/**
* 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.
*/
static int acpi_create_platform_device(struct acpi_device *adev,
const struct acpi_device_id *id)
{
unsigned long flags = id->driver_data;
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;
int count;
if (flags & ACPI_PLATFORM_CLK) {
int ret = acpi_create_platform_clks(adev);
if (ret) {
dev_err(&adev->dev, "failed to create clocks\n");
return ret;
}
}
/* 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;
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);
}