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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * Minimalist driver for a generic PCI-to-EISA bridge.4 *5 * (C) 2003 Marc Zyngier <maz@wild-wind.fr.eu.org>6 *7 * Ivan Kokshaysky <ink@jurassic.park.msu.ru> :8 * Generalisation from i82375 to PCI_CLASS_BRIDGE_EISA.9 */10 11#include <linux/kernel.h>12#include <linux/device.h>13#include <linux/eisa.h>14#include <linux/pci.h>15#include <linux/module.h>16#include <linux/init.h>17 18/* There is only *one* pci_eisa device per machine, right ? */19static struct eisa_root_device pci_eisa_root;20 21static int __init pci_eisa_init(struct pci_dev *pdev)22{23 struct resource *res, *bus_res = NULL;24 int rc;25 26 if ((rc = pci_enable_device (pdev))) {27 dev_err(&pdev->dev, "Could not enable device\n");28 return rc;29 }30 31 /*32 * The Intel 82375 PCI-EISA bridge is a subtractive-decode PCI33 * device, so the resources available on EISA are the same as those34 * available on the 82375 bus. This works the same as a PCI-PCI35 * bridge in subtractive-decode mode (see pci_read_bridge_bases()).36 * We assume other PCI-EISA bridges are similar.37 *38 * eisa_root_register() can only deal with a single io port resource,39 * so we use the first valid io port resource.40 */41 pci_bus_for_each_resource(pdev->bus, res)42 if (res && (res->flags & IORESOURCE_IO)) {43 bus_res = res;44 break;45 }46 47 if (!bus_res) {48 dev_err(&pdev->dev, "No resources available\n");49 return -1;50 }51 52 pci_eisa_root.dev = &pdev->dev;53 pci_eisa_root.res = bus_res;54 pci_eisa_root.bus_base_addr = bus_res->start;55 pci_eisa_root.slots = EISA_MAX_SLOTS;56 pci_eisa_root.dma_mask = pdev->dma_mask;57 dev_set_drvdata(pci_eisa_root.dev, &pci_eisa_root);58 59 if (eisa_root_register (&pci_eisa_root)) {60 dev_err(&pdev->dev, "Could not register EISA root\n");61 return -1;62 }63 64 return 0;65}66 67/*68 * We have to call pci_eisa_init_early() before pnpacpi_init()/isapnp_init().69 * Otherwise pnp resource will get enabled early and could prevent eisa70 * to be initialized.71 * Also need to make sure pci_eisa_init_early() is called after72 * x86/pci_subsys_init().73 * So need to use subsys_initcall_sync with it.74 */75static int __init pci_eisa_init_early(void)76{77 struct pci_dev *dev = NULL;78 int ret;79 80 for_each_pci_dev(dev)81 if ((dev->class >> 8) == PCI_CLASS_BRIDGE_EISA) {82 ret = pci_eisa_init(dev);83 if (ret)84 return ret;85 }86 87 return 0;88}89subsys_initcall_sync(pci_eisa_init_early);90