xref: /openbmc/linux/drivers/eisa/pci_eisa.c (revision 2cfda637)
1 /*
2  * Minimalist driver for a generic PCI-to-EISA bridge.
3  *
4  * (C) 2003 Marc Zyngier <maz@wild-wind.fr.eu.org>
5  *
6  * This code is released under the GPL version 2.
7  *
8  * Ivan Kokshaysky <ink@jurassic.park.msu.ru> :
9  * Generalisation from i82375 to PCI_CLASS_BRIDGE_EISA.
10  */
11 
12 #include <linux/kernel.h>
13 #include <linux/device.h>
14 #include <linux/eisa.h>
15 #include <linux/pci.h>
16 #include <linux/module.h>
17 #include <linux/init.h>
18 
19 /* There is only *one* pci_eisa device per machine, right ? */
20 static struct eisa_root_device pci_eisa_root;
21 
22 static int __init pci_eisa_init(struct pci_dev *pdev,
23 				const struct pci_device_id *ent)
24 {
25 	int rc, i;
26 	struct resource *res, *bus_res = NULL;
27 
28 	if ((rc = pci_enable_device (pdev))) {
29 		printk (KERN_ERR "pci_eisa : Could not enable device %s\n",
30 			pci_name(pdev));
31 		return rc;
32 	}
33 
34 	/*
35 	 * The Intel 82375 PCI-EISA bridge is a subtractive-decode PCI
36 	 * device, so the resources available on EISA are the same as those
37 	 * available on the 82375 bus.  This works the same as a PCI-PCI
38 	 * bridge in subtractive-decode mode (see pci_read_bridge_bases()).
39 	 * We assume other PCI-EISA bridges are similar.
40 	 *
41 	 * eisa_root_register() can only deal with a single io port resource,
42 	*  so we use the first valid io port resource.
43 	 */
44 	pci_bus_for_each_resource(pdev->bus, res, i)
45 		if (res && (res->flags & IORESOURCE_IO)) {
46 			bus_res = res;
47 			break;
48 		}
49 
50 	if (!bus_res) {
51 		dev_err(&pdev->dev, "No resources available\n");
52 		return -1;
53 	}
54 
55 	pci_eisa_root.dev              = &pdev->dev;
56 	pci_eisa_root.res	       = bus_res;
57 	pci_eisa_root.bus_base_addr    = bus_res->start;
58 	pci_eisa_root.slots	       = EISA_MAX_SLOTS;
59 	pci_eisa_root.dma_mask         = pdev->dma_mask;
60 	dev_set_drvdata(pci_eisa_root.dev, &pci_eisa_root);
61 
62 	if (eisa_root_register (&pci_eisa_root)) {
63 		printk (KERN_ERR "pci_eisa : Could not register EISA root\n");
64 		return -1;
65 	}
66 
67 	return 0;
68 }
69 
70 static struct pci_device_id pci_eisa_pci_tbl[] = {
71 	{ PCI_ANY_ID, PCI_ANY_ID, PCI_ANY_ID, PCI_ANY_ID,
72 	  PCI_CLASS_BRIDGE_EISA << 8, 0xffff00, 0 },
73 	{ 0, }
74 };
75 
76 static struct pci_driver __refdata pci_eisa_driver = {
77 	.name		= "pci_eisa",
78 	.id_table	= pci_eisa_pci_tbl,
79 	.probe		= pci_eisa_init,
80 };
81 
82 static int __init pci_eisa_init_module (void)
83 {
84 	return pci_register_driver (&pci_eisa_driver);
85 }
86 
87 device_initcall(pci_eisa_init_module);
88 MODULE_DEVICE_TABLE(pci, pci_eisa_pci_tbl);
89