drivers/pnp/system.c

   1 /*
   2  * system.c - a driver for reserving pnp system resources
   3  *
   4  * Some code is based on pnpbios_core.c
   5  * Copyright 2002 Adam Belay <ambx1@neo.rr.com>
   6  * (c) Copyright 2007 Hewlett-Packard Development Company, L.P.
   7  *      Bjorn Helgaas <bjorn.helgaas@hp.com>
   8  */
   9
  10 #include <linux/pnp.h>
  11 #include <linux/device.h>
  12 #include <linux/init.h>
  13 #include <linux/slab.h>
  14 #include <linux/kernel.h>
  15 #include <linux/ioport.h>
  16
  17 static const struct pnp_device_id pnp_dev_table[] = {
  18         /* General ID for reserving resources */
  19         {"PNP0c02", 0},
  20         /* memory controller */
  21         {"PNP0c01", 0},
  22         {"", 0}
  23 };
  24
  25 static void reserve_range(const char *pnpid, resource_size_t start,
  26                           resource_size_t end, int port)
  27 {
  28         struct resource *res;
  29         char *regionid;
  30
  31         regionid = kmalloc(16, GFP_KERNEL);
  32         if (regionid == NULL)
  33                 return;
  34         snprintf(regionid, 16, "pnp %s", pnpid);
  35         if (port)
  36                 res = request_region(start, end - start + 1, regionid);
  37         else
  38                 res = request_mem_region(start, end - start + 1, regionid);
  39         if (res == NULL)
  40                 kfree(regionid);
  41         else
  42                 res->flags &= ~IORESOURCE_BUSY;
  43         /*
  44          * Failures at this point are usually harmless. pci quirks for
  45          * example do reserve stuff they know about too, so we may well
  46          * have double reservations.
  47          */
  48         printk(KERN_INFO "pnp: %s: %s range 0x%llx-0x%llx %s reserved\n",
  49                pnpid, port ? "ioport" : "iomem",
  50                (unsigned long long)start, (unsigned long long)end,
  51                NULL != res ? "has been" : "could not be");
  52 }
  53
  54 static void reserve_resources_of_dev(const struct pnp_dev *dev)
  55 {
  56         int i;
  57
  58         for (i = 0; i < PNP_MAX_PORT; i++) {
  59                 if (!pnp_port_valid(dev, i))
  60                         continue;
  61                 if (pnp_port_start(dev, i) == 0)
  62                         continue;       /* disabled */
  63                 if (pnp_port_start(dev, i) < 0x100)
  64                         /*
  65                          * Below 0x100 is only standard PC hardware
  66                          * (pics, kbd, timer, dma, ...)
  67                          * We should not get resource conflicts there,
  68                          * and the kernel reserves these anyway
  69                          * (see arch/i386/kernel/setup.c).
  70                          * So, do nothing
  71                          */
  72                         continue;
  73                 if (pnp_port_end(dev, i) < pnp_port_start(dev, i))
  74                         continue;       /* invalid */
  75
  76                 reserve_range(dev->dev.bus_id, pnp_port_start(dev, i),
  77                               pnp_port_end(dev, i), 1);
  78         }
  79
  80         for (i = 0; i < PNP_MAX_MEM; i++) {
  81                 if (!pnp_mem_valid(dev, i))
  82                         continue;
  83
  84                 reserve_range(dev->dev.bus_id, pnp_mem_start(dev, i),
  85                               pnp_mem_end(dev, i), 0);
  86         }
  87 }
  88
  89 static int system_pnp_probe(struct pnp_dev *dev,
  90                             const struct pnp_device_id *dev_id)
  91 {
  92         reserve_resources_of_dev(dev);
  93         return 0;
  94 }
  95
  96 static struct pnp_driver system_pnp_driver = {
  97         .name     = "system",
  98         .id_table = pnp_dev_table,
  99         .flags    = PNP_DRIVER_RES_DO_NOT_CHANGE,
 100         .probe    = system_pnp_probe,
 101 };
 102
 103 static int __init pnp_system_init(void)
 104 {
 105         return pnp_register_driver(&system_pnp_driver);
 106 }
 107
 108 /**
 109  * Reserve motherboard resources after PCI claim BARs,
 110  * but before PCI assign resources for uninitialized PCI devices
 111  */
 112 fs_initcall(pnp_system_init);