242d3a872011776dee58067a763ca617c7d6a104
[linux-2.6.git] / 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(struct pnp_dev *dev, struct resource *r, int port)
26 {
27         char *regionid;
28         const char *pnpid = dev_name(&dev->dev);
29         resource_size_t start = r->start, end = r->end;
30         struct resource *res;
31
32         regionid = kmalloc(16, GFP_KERNEL);
33         if (!regionid)
34                 return;
35
36         snprintf(regionid, 16, "pnp %s", pnpid);
37         if (port)
38                 res = request_region(start, end - start + 1, regionid);
39         else
40                 res = request_mem_region(start, end - start + 1, regionid);
41         if (res)
42                 res->flags &= ~IORESOURCE_BUSY;
43         else
44                 kfree(regionid);
45
46         /*
47          * Failures at this point are usually harmless. pci quirks for
48          * example do reserve stuff they know about too, so we may well
49          * have double reservations.
50          */
51         dev_info(&dev->dev, "%pRt %s reserved\n", r,
52                  res ? "has been" : "could not be");
53 }
54
55 static void reserve_resources_of_dev(struct pnp_dev *dev)
56 {
57         struct resource *res;
58         int i;
59
60         for (i = 0; (res = pnp_get_resource(dev, IORESOURCE_IO, i)); i++) {
61                 if (res->flags & IORESOURCE_DISABLED)
62                         continue;
63                 if (res->start == 0)
64                         continue;       /* disabled */
65                 if (res->start < 0x100)
66                         /*
67                          * Below 0x100 is only standard PC hardware
68                          * (pics, kbd, timer, dma, ...)
69                          * We should not get resource conflicts there,
70                          * and the kernel reserves these anyway
71                          * (see arch/i386/kernel/setup.c).
72                          * So, do nothing
73                          */
74                         continue;
75                 if (res->end < res->start)
76                         continue;       /* invalid */
77
78                 reserve_range(dev, res, 1);
79         }
80
81         for (i = 0; (res = pnp_get_resource(dev, IORESOURCE_MEM, i)); i++) {
82                 if (res->flags & IORESOURCE_DISABLED)
83                         continue;
84
85                 reserve_range(dev, res, 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);