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
pci_eisa_init(struct pci_dev * pdev)22 static int __init pci_eisa_init(struct pci_dev *pdev)
23 {
24 int rc, i;
25 struct resource *res, *bus_res = NULL;
26
27 if ((rc = pci_enable_device (pdev))) {
28 dev_err(&pdev->dev, "Could not enable device\n");
29 return rc;
30 }
31
32 /*
33 * The Intel 82375 PCI-EISA bridge is a subtractive-decode PCI
34 * device, so the resources available on EISA are the same as those
35 * available on the 82375 bus. This works the same as a PCI-PCI
36 * bridge in subtractive-decode mode (see pci_read_bridge_bases()).
37 * We assume other PCI-EISA bridges are similar.
38 *
39 * eisa_root_register() can only deal with a single io port resource,
40 * so we use the first valid io port resource.
41 */
42 pci_bus_for_each_resource(pdev->bus, res, i)
43 if (res && (res->flags & IORESOURCE_IO)) {
44 bus_res = res;
45 break;
46 }
47
48 if (!bus_res) {
49 dev_err(&pdev->dev, "No resources available\n");
50 return -1;
51 }
52
53 pci_eisa_root.dev = &pdev->dev;
54 pci_eisa_root.res = bus_res;
55 pci_eisa_root.bus_base_addr = bus_res->start;
56 pci_eisa_root.slots = EISA_MAX_SLOTS;
57 pci_eisa_root.dma_mask = pdev->dma_mask;
58 dev_set_drvdata(pci_eisa_root.dev, &pci_eisa_root);
59
60 if (eisa_root_register (&pci_eisa_root)) {
61 dev_err(&pdev->dev, "Could not register EISA root\n");
62 return -1;
63 }
64
65 return 0;
66 }
67
68 /*
69 * We have to call pci_eisa_init_early() before pnpacpi_init()/isapnp_init().
70 * Otherwise pnp resource will get enabled early and could prevent eisa
71 * to be initialized.
72 * Also need to make sure pci_eisa_init_early() is called after
73 * x86/pci_subsys_init().
74 * So need to use subsys_initcall_sync with it.
75 */
pci_eisa_init_early(void)76 static int __init pci_eisa_init_early(void)
77 {
78 struct pci_dev *dev = NULL;
79 int ret;
80
81 for_each_pci_dev(dev)
82 if ((dev->class >> 8) == PCI_CLASS_BRIDGE_EISA) {
83 ret = pci_eisa_init(dev);
84 if (ret)
85 return ret;
86 }
87
88 return 0;
89 }
90 subsys_initcall_sync(pci_eisa_init_early);
91
