alistair23-linux/drivers/acpi/acpi_platform.c
Suthikulpanit, Suravee d056267483 ACPI / scan: Parse _CCA and setup device coherency
This patch implements support for ACPI _CCA object, which is introduced in
ACPIv5.1, can be used for specifying device DMA coherency attribute.

The parsing logic traverses device namespace to parse coherency
information, and stores it in acpi_device_flags. Then uses it to call
arch_setup_dma_ops() when creating each device enumerated in DSDT
during ACPI scan.

This patch also introduces acpi_dma_is_coherent(), which provides
an interface for device drivers to check the coherency information
similarly to the of_dma_is_coherent().

Signed-off-by: Mark Salter <msalter@redhat.com>
Signed-off-by: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-06-15 14:40:48 +02:00

119 lines
3.5 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/dma-mapping.h>
#include <linux/platform_device.h>
#include "internal.h"
ACPI_MODULE_NAME("platform");
static const struct acpi_device_id forbidden_id_list[] = {
{"PNP0000", 0}, /* PIC */
{"PNP0100", 0}, /* Timer */
{"PNP0200", 0}, /* AT DMA Controller */
{"", 0},
};
/**
* acpi_create_platform_device - Create platform device for ACPI device node
* @adev: ACPI device node to create a platform device for.
*
* 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)
{
struct platform_device *pdev = NULL;
struct acpi_device *acpi_parent;
struct platform_device_info pdevinfo;
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;
if (!acpi_match_device_ids(adev, forbidden_id_list))
return ERR_PTR(-EINVAL);
INIT_LIST_HEAD(&resource_list);
count = acpi_dev_get_resources(adev, &resource_list, NULL, NULL);
if (count < 0) {
return NULL;
} 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 ERR_PTR(-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.fwnode = acpi_fwnode_handle(adev);
pdevinfo.dma_mask = acpi_check_dma(adev, NULL) ? DMA_BIT_MASK(32) : 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
dev_dbg(&adev->dev, "created platform device %s\n",
dev_name(&pdev->dev));
kfree(resources);
return pdev;
}
EXPORT_SYMBOL_GPL(acpi_create_platform_device);