| Kyle Swenson | 8d8f654 | 2021-03-15 11:02:55 -0600 | [diff] [blame^] | 1 | /* pci-stub - simple stub driver to reserve a pci device |
| 2 | * |
| 3 | * Copyright (C) 2008 Red Hat, Inc. |
| 4 | * Author: |
| 5 | * Chris Wright |
| 6 | * |
| 7 | * This work is licensed under the terms of the GNU GPL, version 2. |
| 8 | * |
| 9 | * Usage is simple, allocate a new id to the stub driver and bind the |
| 10 | * device to it. For example: |
| 11 | * |
| 12 | * # echo "8086 10f5" > /sys/bus/pci/drivers/pci-stub/new_id |
| 13 | * # echo -n 0000:00:19.0 > /sys/bus/pci/drivers/e1000e/unbind |
| 14 | * # echo -n 0000:00:19.0 > /sys/bus/pci/drivers/pci-stub/bind |
| 15 | * # ls -l /sys/bus/pci/devices/0000:00:19.0/driver |
| 16 | * .../0000:00:19.0/driver -> ../../../bus/pci/drivers/pci-stub |
| 17 | */ |
| 18 | |
| 19 | #include <linux/module.h> |
| 20 | #include <linux/pci.h> |
| 21 | |
| 22 | static char ids[1024] __initdata; |
| 23 | |
| 24 | module_param_string(ids, ids, sizeof(ids), 0); |
| 25 | MODULE_PARM_DESC(ids, "Initial PCI IDs to add to the stub driver, format is " |
| 26 | "\"vendor:device[:subvendor[:subdevice[:class[:class_mask]]]]\"" |
| 27 | " and multiple comma separated entries can be specified"); |
| 28 | |
| 29 | static int pci_stub_probe(struct pci_dev *dev, const struct pci_device_id *id) |
| 30 | { |
| 31 | dev_info(&dev->dev, "claimed by stub\n"); |
| 32 | return 0; |
| 33 | } |
| 34 | |
| 35 | static struct pci_driver stub_driver = { |
| 36 | .name = "pci-stub", |
| 37 | .id_table = NULL, /* only dynamic id's */ |
| 38 | .probe = pci_stub_probe, |
| 39 | }; |
| 40 | |
| 41 | static int __init pci_stub_init(void) |
| 42 | { |
| 43 | char *p, *id; |
| 44 | int rc; |
| 45 | |
| 46 | rc = pci_register_driver(&stub_driver); |
| 47 | if (rc) |
| 48 | return rc; |
| 49 | |
| 50 | /* no ids passed actually */ |
| 51 | if (ids[0] == '\0') |
| 52 | return 0; |
| 53 | |
| 54 | /* add ids specified in the module parameter */ |
| 55 | p = ids; |
| 56 | while ((id = strsep(&p, ","))) { |
| 57 | unsigned int vendor, device, subvendor = PCI_ANY_ID, |
| 58 | subdevice = PCI_ANY_ID, class = 0, class_mask = 0; |
| 59 | int fields; |
| 60 | |
| 61 | if (!strlen(id)) |
| 62 | continue; |
| 63 | |
| 64 | fields = sscanf(id, "%x:%x:%x:%x:%x:%x", |
| 65 | &vendor, &device, &subvendor, &subdevice, |
| 66 | &class, &class_mask); |
| 67 | |
| 68 | if (fields < 2) { |
| 69 | printk(KERN_WARNING |
| 70 | "pci-stub: invalid id string \"%s\"\n", id); |
| 71 | continue; |
| 72 | } |
| 73 | |
| 74 | printk(KERN_INFO |
| 75 | "pci-stub: add %04X:%04X sub=%04X:%04X cls=%08X/%08X\n", |
| 76 | vendor, device, subvendor, subdevice, class, class_mask); |
| 77 | |
| 78 | rc = pci_add_dynid(&stub_driver, vendor, device, |
| 79 | subvendor, subdevice, class, class_mask, 0); |
| 80 | if (rc) |
| 81 | printk(KERN_WARNING |
| 82 | "pci-stub: failed to add dynamic id (%d)\n", rc); |
| 83 | } |
| 84 | |
| 85 | return 0; |
| 86 | } |
| 87 | |
| 88 | static void __exit pci_stub_exit(void) |
| 89 | { |
| 90 | pci_unregister_driver(&stub_driver); |
| 91 | } |
| 92 | |
| 93 | module_init(pci_stub_init); |
| 94 | module_exit(pci_stub_exit); |
| 95 | |
| 96 | MODULE_LICENSE("GPL"); |
| 97 | MODULE_AUTHOR("Chris Wright <chrisw@sous-sol.org>"); |