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(char *pnpid, int start, int end, int port)
  26 {
  27         struct resource *res;
  28         char *regionid;
  29
  30         regionid = kmalloc(16, GFP_KERNEL);
  31         if (regionid == NULL)
  32                 return;
  33         snprintf(regionid, 16, "pnp %s", pnpid);
  34         if (port)
  35                 res = request_region(start,end-start+1,regionid);
  36         else
  37                 res = request_mem_region(start,end-start+1,regionid);
  38         if (res == NULL)
  39                 kfree(regionid);
  40         else
  41                 res->flags &= ~IORESOURCE_BUSY;
  42         /*
  43          * Failures at this point are usually harmless. pci quirks for
  44          * example do reserve stuff they know about too, so we may well
  45          * have double reservations.
  46          */
  47         printk(KERN_INFO
  48                 "pnp: %s: %s range 0x%x-0x%x %s reserved\n",
  49                 pnpid, port ? "ioport" : "iomem", start, end,
  50                 NULL != res ? "has been" : "could not be");
  51 }
  52
  53 static void reserve_resources_of_dev(struct pnp_dev *dev)
  54 {
  55         int i;
  56
  57         for (i = 0; i < PNP_MAX_PORT; i++) {
  58                 if (!pnp_port_valid(dev, i))
  59                         continue;
  60                 if (pnp_port_start(dev, i) == 0)
  61                         continue;       /* disabled */
  62                 if (pnp_port_start(dev, i) < 0x100)
  63                         /*
  64                          * Below 0x100 is only standard PC hardware
  65                          * (pics, kbd, timer, dma, ...)
  66                          * We should not get resource conflicts there,
  67                          * and the kernel reserves these anyway
  68                          * (see arch/i386/kernel/setup.c).
  69                          * So, do nothing
  70                          */
  71                         continue;
  72                 if (pnp_port_end(dev, i) < pnp_port_start(dev, i))
  73                         continue;       /* invalid */
  74
  75                 reserve_range(dev->dev.bus_id, pnp_port_start(dev, i),
  76                         pnp_port_end(dev, i), 1);
  77         }
  78
  79         for (i = 0; i < PNP_MAX_MEM; i++) {
  80                 if (!pnp_mem_valid(dev, i))
  81                         continue;
  82
  83                 reserve_range(dev->dev.bus_id, pnp_mem_start(dev, i),
  84                         pnp_mem_end(dev, i), 0);
  85         }
  86
  87         return;
  88 }
  89
  90 static int system_pnp_probe(struct pnp_dev * dev, 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         .remove         = NULL,
 102 };
 103
 104 static int __init pnp_system_init(void)
 105 {
 106         return pnp_register_driver(&system_pnp_driver);
 107 }
 108
 109 /**
 110  * Reserve motherboard resources after PCI claim BARs,
 111  * but before PCI assign resources for uninitialized PCI devices
 112  */
 113 fs_initcall(pnp_system_init);