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  *
   7  */
   8
   9 #include <linux/pnp.h>
  10 #include <linux/device.h>
  11 #include <linux/init.h>
  12 #include <linux/slab.h>
  13 #include <linux/kernel.h>
  14 #include <linux/ioport.h>
  15
  16 static const struct pnp_device_id pnp_dev_table[] = {
  17         /* General ID for reserving resources */
  18         {       "PNP0c02",              0       },
  19         /* memory controller */
  20         {       "PNP0c01",              0       },
  21         {       "",                     0       }
  22 };
  23
  24 static void reserve_ioport_range(char *pnpid, int start, int end)
  25 {
  26         struct resource *res;
  27         char *regionid;
  28
  29         regionid = kmalloc(16, GFP_KERNEL);
  30         if ( regionid == NULL )
  31                 return;
  32         snprintf(regionid, 16, "pnp %s", pnpid);
  33         res = request_region(start,end-start+1,regionid);
  34         if ( res == NULL )
  35                 kfree( regionid );
  36         else
  37                 res->flags &= ~IORESOURCE_BUSY;
  38         /*
  39          * Failures at this point are usually harmless. pci quirks for
  40          * example do reserve stuff they know about too, so we may well
  41          * have double reservations.
  42          */
  43         printk(KERN_INFO
  44                 "pnp: %s: ioport range 0x%x-0x%x %s reserved\n",
  45                 pnpid, start, end,
  46                 NULL != res ? "has been" : "could not be"
  47         );
  48
  49         return;
  50 }
  51
  52 static void reserve_resources_of_dev( struct pnp_dev *dev )
  53 {
  54         int i;
  55
  56         for (i=0;i<PNP_MAX_PORT;i++) {
  57                 if (!pnp_port_valid(dev, i))
  58                         /* end of resources */
  59                         continue;
  60                 if (pnp_port_start(dev, i) == 0)
  61                         /* disabled */
  62                         /* Do nothing */
  63                         continue;
  64                 if (pnp_port_start(dev, i) < 0x100)
  65                         /*
  66                          * Below 0x100 is only standard PC hardware
  67                          * (pics, kbd, timer, dma, ...)
  68                          * We should not get resource conflicts there,
  69                          * and the kernel reserves these anyway
  70                          * (see arch/i386/kernel/setup.c).
  71                          * So, do nothing
  72                          */
  73                         continue;
  74                 if (pnp_port_end(dev, i) < pnp_port_start(dev, i))
  75                         /* invalid endpoint */
  76                         /* Do nothing */
  77                         continue;
  78                 reserve_ioport_range(
  79                         dev->dev.bus_id,
  80                         pnp_port_start(dev, i),
  81                         pnp_port_end(dev, i)
  82                 );
  83         }
  84
  85         return;
  86 }
  87
  88 static int system_pnp_probe(struct pnp_dev * dev, const struct pnp_device_id *dev_id)
  89 {
  90         reserve_resources_of_dev(dev);
  91         return 0;
  92 }
  93
  94 static struct pnp_driver system_pnp_driver = {
  95         .name           = "system",
  96         .id_table       = pnp_dev_table,
  97         .flags          = PNP_DRIVER_RES_DO_NOT_CHANGE,
  98         .probe          = system_pnp_probe,
  99         .remove         = NULL,
 100 };
 101
 102 static int __init pnp_system_init(void)
 103 {
 104         return pnp_register_driver(&system_pnp_driver);
 105 }
 106
 107 subsys_initcall(pnp_system_init);