diff options
Diffstat (limited to 'drivers/pci/hotplug/fakephp.c')
-rw-r--r-- | drivers/pci/hotplug/fakephp.c | 162 |
1 files changed, 162 insertions, 0 deletions
diff --git a/drivers/pci/hotplug/fakephp.c b/drivers/pci/hotplug/fakephp.c new file mode 100644 index 000000000000..2dc7828df480 --- /dev/null +++ b/drivers/pci/hotplug/fakephp.c @@ -0,0 +1,162 @@ +/* Works like the fakephp driver used to, except a little better. + * + * - It's possible to remove devices with subordinate busses. + * - New PCI devices that appear via any method, not just a fakephp triggered + * rescan, will be noticed. + * - Devices that are removed via any method, not just a fakephp triggered + * removal, will also be noticed. + * + * Uses nothing from the pci-hotplug subsystem. + * + */ + +#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/types.h> +#include <linux/list.h> +#include <linux/kobject.h> +#include <linux/sysfs.h> +#include <linux/init.h> +#include <linux/pci.h> +#include "../pci.h" + +struct legacy_slot { + struct kobject kobj; + struct pci_dev *dev; + struct list_head list; +}; + +static LIST_HEAD(legacy_list); + +static ssize_t legacy_show(struct kobject *kobj, struct attribute *attr, + char *buf) +{ + struct legacy_slot *slot = container_of(kobj, typeof(*slot), kobj); + strcpy(buf, "1\n"); + return 2; +} + +static void remove_callback(void *data) +{ + pci_remove_bus_device((struct pci_dev *)data); +} + +static ssize_t legacy_store(struct kobject *kobj, struct attribute *attr, + const char *buf, size_t len) +{ + struct legacy_slot *slot = container_of(kobj, typeof(*slot), kobj); + unsigned long val; + + if (strict_strtoul(buf, 0, &val) < 0) + return -EINVAL; + + if (val) + pci_rescan_bus(slot->dev->bus); + else + sysfs_schedule_callback(&slot->dev->dev.kobj, remove_callback, + slot->dev, THIS_MODULE); + return len; +} + +static struct attribute *legacy_attrs[] = { + &(struct attribute){ .name = "power", .mode = 0644 }, + NULL, +}; + +static void legacy_release(struct kobject *kobj) +{ + struct legacy_slot *slot = container_of(kobj, typeof(*slot), kobj); + + pci_dev_put(slot->dev); + kfree(slot); +} + +static struct kobj_type legacy_ktype = { + .sysfs_ops = &(struct sysfs_ops){ + .store = legacy_store, .show = legacy_show + }, + .release = &legacy_release, + .default_attrs = legacy_attrs, +}; + +static int legacy_add_slot(struct pci_dev *pdev) +{ + struct legacy_slot *slot = kzalloc(sizeof(*slot), GFP_KERNEL); + + if (!slot) + return -ENOMEM; + + if (kobject_init_and_add(&slot->kobj, &legacy_ktype, + &pci_slots_kset->kobj, "%s", + pdev->dev.bus_id)) { + dev_warn(&pdev->dev, "Failed to created legacy fake slot\n"); + return -EINVAL; + } + slot->dev = pci_dev_get(pdev); + + list_add(&slot->list, &legacy_list); + + return 0; +} + +static int legacy_notify(struct notifier_block *nb, + unsigned long action, void *data) +{ + struct pci_dev *pdev = to_pci_dev(data); + + if (action == BUS_NOTIFY_ADD_DEVICE) { + legacy_add_slot(pdev); + } else if (action == BUS_NOTIFY_DEL_DEVICE) { + struct legacy_slot *slot; + + list_for_each_entry(slot, &legacy_list, list) + if (slot->dev == pdev) + goto found; + + dev_warn(&pdev->dev, "Missing legacy fake slot?"); + return -ENODEV; +found: + kobject_del(&slot->kobj); + list_del(&slot->list); + kobject_put(&slot->kobj); + } + + return 0; +} + +static struct notifier_block legacy_notifier = { + .notifier_call = legacy_notify +}; + +static int __init init_legacy(void) +{ + struct pci_dev *pdev = NULL; + + /* Add existing devices */ + while ((pdev = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, pdev))) + legacy_add_slot(pdev); + + /* Be alerted of any new ones */ + bus_register_notifier(&pci_bus_type, &legacy_notifier); + return 0; +} +module_init(init_legacy); + +static void __exit remove_legacy(void) +{ + struct legacy_slot *slot, *tmp; + + bus_unregister_notifier(&pci_bus_type, &legacy_notifier); + + list_for_each_entry_safe(slot, tmp, &legacy_list, list) { + list_del(&slot->list); + kobject_del(&slot->kobj); + kobject_put(&slot->kobj); + } +} +module_exit(remove_legacy); + + +MODULE_AUTHOR("Trent Piepho <xyzzy@speakeasy.org>"); +MODULE_DESCRIPTION("Legacy version of the fakephp interface"); +MODULE_LICENSE("GPL"); |