LXR linux/drivers/eisa/pci

   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 ? */
  20static struct eisa_root_device pci_eisa_root;
  21
  22static 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 */
  76static 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}
  90subsys_initcall_sync(pci_eisa_init_early);
  91