// SPDX-License-Identifier: GPL-2.0 /* * Simple stub driver to reserve a PCI device * * Copyright (C) 2008 Red Hat, Inc. * Author: * Chris Wright * * Usage is simple, allocate a new id to the stub driver and bind the * device to it. For example: * * # echo "8086 10f5" > /sys/bus/pci/drivers/pci-stub/new_id * # echo -n 0000:00:19.0 > /sys/bus/pci/drivers/e1000e/unbind * # echo -n 0000:00:19.0 > /sys/bus/pci/drivers/pci-stub/bind * # ls -l /sys/bus/pci/devices/0000:00:19.0/driver * .../0000:00:19.0/driver -> ../../../bus/pci/drivers/pci-stub */ #include <linux/module.h> #include <linux/pci.h> static char ids[1024] __initdata; module_param_string(ids, ids, sizeof(ids), 0); MODULE_PARM_DESC(ids, "Initial PCI IDs to add to the stub driver, format is " "\"vendor:device[:subvendor[:subdevice[:class[:class_mask]]]]\"" " and multiple comma separated entries can be specified"); static int pci_stub_probe(struct pci_dev *dev, const struct pci_device_id *id) { pci_info(dev, "claimed by stub\n"); return 0; } static struct pci_driver stub_driver = { .name = "pci-stub", .id_table = NULL, /* only dynamic id's */ .probe = pci_stub_probe, }; static int __init pci_stub_init(void) { char *p, *id; int rc; rc = pci_register_driver(&stub_driver); if (rc) return rc; /* no ids passed actually */ if (ids[0] == '\0') return 0; /* add ids specified in the module parameter */ p = ids; while ((id = strsep(&p, ","))) { unsigned int vendor, device, subvendor = PCI_ANY_ID, subdevice = PCI_ANY_ID, class = 0, class_mask = 0; int fields; if (!strlen(id)) continue; fields = sscanf(id, "%x:%x:%x:%x:%x:%x", &vendor, &device, &subvendor, &subdevice, &class, &class_mask); if (fields < 2) { pr_warn("pci-stub: invalid ID string \"%s\"\n", id); continue; } pr_info("pci-stub: add %04X:%04X sub=%04X:%04X cls=%08X/%08X\n", vendor, device, subvendor, subdevice, class, class_mask); rc = pci_add_dynid(&stub_driver, vendor, device, subvendor, subdevice, class, class_mask, 0); if (rc) pr_warn("pci-stub: failed to add dynamic ID (%d)\n", rc); } return 0; } static void __exit pci_stub_exit(void) { pci_unregister_driver(&stub_driver); } module_init(pci_stub_init); module_exit(pci_stub_exit); MODULE_LICENSE("GPL"); MODULE_AUTHOR("Chris Wright <chrisw@sous-sol.org>");