drivers/acpi/acpi_platform.c

   1 /*
   2  * ACPI support for platform bus type.
   3  *
   4  * Copyright (C) 2012, Intel Corporation
   5  * Authors: Mika Westerberg <mika.westerberg@linux.intel.com>
   6  *          Mathias Nyman <mathias.nyman@linux.intel.com>
   7  *          Rafael J. Wysocki <rafael.j.wysocki@intel.com>
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License version 2 as
  11  * published by the Free Software Foundation.
  12  */
  13
  14 #include <linux/acpi.h>
  15 #include <linux/device.h>
  16 #include <linux/err.h>
  17 #include <linux/kernel.h>
  18 #include <linux/module.h>
  19 #include <linux/dma-mapping.h>
  20 #include <linux/pci.h>
  21 #include <linux/platform_device.h>
  22
  23 #include "internal.h"
  24
  25 ACPI_MODULE_NAME("platform");
  26
  27 static const struct acpi_device_id forbidden_id_list[] = {
  28         {"PNP0000",  0},        /* PIC */
  29         {"PNP0100",  0},        /* Timer */
  30         {"PNP0200",  0},        /* AT DMA Controller */
  31         {"ACPI0009", 0},        /* IOxAPIC */
  32         {"ACPI000A", 0},        /* IOAPIC */
  33         {"SMB0001",  0},        /* ACPI SMBUS virtual device */
  34         {"", 0},
  35 };
  36
  37 static void acpi_platform_fill_resource(struct acpi_device *adev,
  38         const struct resource *src, struct resource *dest)
  39 {
  40         struct device *parent;
  41
  42         *dest = *src;
  43
  44         /*
  45          * If the device has parent we need to take its resources into
  46          * account as well because this device might consume part of those.
  47          */
  48         parent = acpi_get_first_physical_node(adev->parent);
  49         if (parent && dev_is_pci(parent))
  50                 dest->parent = pci_find_resource(to_pci_dev(parent), dest);
  51 }
  52
  53 /**
  54  * acpi_create_platform_device - Create platform device for ACPI device node
  55  * @adev: ACPI device node to create a platform device for.
  56  * @properties: Optional collection of build-in properties.
  57  *
  58  * Check if the given @adev can be represented as a platform device and, if
  59  * that's the case, create and register a platform device, populate its common
  60  * resources and returns a pointer to it.  Otherwise, return %NULL.
  61  *
  62  * Name of the platform device will be the same as @adev's.
  63  */
  64 struct platform_device *acpi_create_platform_device(struct acpi_device *adev,
  65                                         struct property_entry *properties)
  66 {
  67         struct platform_device *pdev = NULL;
  68         struct platform_device_info pdevinfo;
  69         struct resource_entry *rentry;
  70         struct list_head resource_list;
  71         struct resource *resources = NULL;
  72         int count;
  73
  74         /* If the ACPI node already has a physical device attached, skip it. */
  75         if (adev->physical_node_count)
  76                 return NULL;
  77
  78         if (!acpi_match_device_ids(adev, forbidden_id_list))
  79                 return ERR_PTR(-EINVAL);
  80
  81         INIT_LIST_HEAD(&resource_list);
  82         count = acpi_dev_get_resources(adev, &resource_list, NULL, NULL);
  83         if (count < 0) {
  84                 return NULL;
  85         } else if (count > 0) {
  86                 resources = kcalloc(count, sizeof(struct resource),
  87                                     GFP_KERNEL);
  88                 if (!resources) {
  89                         dev_err(&adev->dev, "No memory for resources\n");
  90                         acpi_dev_free_resource_list(&resource_list);
  91                         return ERR_PTR(-ENOMEM);
  92                 }
  93                 count = 0;
  94                 list_for_each_entry(rentry, &resource_list, node)
  95                         acpi_platform_fill_resource(adev, rentry->res,
  96                                                     &resources[count++]);
  97
  98                 acpi_dev_free_resource_list(&resource_list);
  99         }
 100
 101         memset(&pdevinfo, 0, sizeof(pdevinfo));
 102         /*
 103          * If the ACPI node has a parent and that parent has a physical device
 104          * attached to it, that physical device should be the parent of the
 105          * platform device we are about to create.
 106          */
 107         pdevinfo.parent = adev->parent ?
 108                 acpi_get_first_physical_node(adev->parent) : NULL;
 109         pdevinfo.name = dev_name(&adev->dev);
 110         pdevinfo.id = -1;
 111         pdevinfo.res = resources;
 112         pdevinfo.num_res = count;
 113         pdevinfo.fwnode = acpi_fwnode_handle(adev);
 114         pdevinfo.properties = properties;
 115
 116         if (acpi_dma_supported(adev))
 117                 pdevinfo.dma_mask = DMA_BIT_MASK(32);
 118         else
 119                 pdevinfo.dma_mask = 0;
 120
 121         pdev = platform_device_register_full(&pdevinfo);
 122         if (IS_ERR(pdev))
 123                 dev_err(&adev->dev, "platform device creation failed: %ld\n",
 124                         PTR_ERR(pdev));
 125         else {
 126                 set_dev_node(&pdev->dev, acpi_get_node(adev->handle));
 127                 dev_dbg(&adev->dev, "created platform device %s\n",
 128                         dev_name(&pdev->dev));
 129         }
 130
 131         kfree(resources);
 132
 133         return pdev;
 134 }
 135 EXPORT_SYMBOL_GPL(acpi_create_platform_device);