xref: /linux/drivers/pnp/system.c (revision d9bc125caf592b7d081021f32ce5b717efdf70c8)
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);
114