3 * Copyright (C) 2006 Matthew Wilcox <matthew@wil.cx>
4 * Copyright (C) 2006-2009 Hewlett-Packard Development Company, L.P.
5 * Alex Chiang <achiang@hp.com>
8 #include <linux/kobject.h>
10 #include <linux/err.h>
13 struct kset *pci_slots_kset;
14 EXPORT_SYMBOL_GPL(pci_slots_kset);
16 static ssize_t pci_slot_attr_show(struct kobject *kobj,
17 struct attribute *attr, char *buf)
19 struct pci_slot *slot = to_pci_slot(kobj);
20 struct pci_slot_attribute *attribute = to_pci_slot_attr(attr);
21 return attribute->show ? attribute->show(slot, buf) : -EIO;
24 static ssize_t pci_slot_attr_store(struct kobject *kobj,
25 struct attribute *attr, const char *buf, size_t len)
27 struct pci_slot *slot = to_pci_slot(kobj);
28 struct pci_slot_attribute *attribute = to_pci_slot_attr(attr);
29 return attribute->store ? attribute->store(slot, buf, len) : -EIO;
32 static struct sysfs_ops pci_slot_sysfs_ops = {
33 .show = pci_slot_attr_show,
34 .store = pci_slot_attr_store,
37 static ssize_t address_read_file(struct pci_slot *slot, char *buf)
39 if (slot->number == 0xff)
40 return sprintf(buf, "%04x:%02x\n",
41 pci_domain_nr(slot->bus),
44 return sprintf(buf, "%04x:%02x:%02x\n",
45 pci_domain_nr(slot->bus),
50 /* these strings match up with the values in pci_bus_speed */
51 static char *pci_bus_speed_strings[] = {
52 "33 MHz PCI", /* 0x00 */
53 "66 MHz PCI", /* 0x01 */
54 "66 MHz PCI-X", /* 0x02 */
55 "100 MHz PCI-X", /* 0x03 */
56 "133 MHz PCI-X", /* 0x04 */
61 "66 MHz PCI-X 266", /* 0x09 */
62 "100 MHz PCI-X 266", /* 0x0a */
63 "133 MHz PCI-X 266", /* 0x0b */
69 "66 MHz PCI-X 533", /* 0x11 */
70 "100 MHz PCI-X 533", /* 0x12 */
71 "133 MHz PCI-X 533", /* 0x13 */
72 "2.5 GT/s PCIe", /* 0x14 */
73 "5.0 GT/s PCIe", /* 0x15 */
76 static ssize_t bus_speed_read(enum pci_bus_speed speed, char *buf)
78 const char *speed_string;
80 if (speed < ARRAY_SIZE(pci_bus_speed_strings))
81 speed_string = pci_bus_speed_strings[speed];
83 speed_string = "Unknown";
85 return sprintf(buf, "%s\n", speed_string);
88 static ssize_t max_speed_read_file(struct pci_slot *slot, char *buf)
90 return bus_speed_read(slot->bus->max_bus_speed, buf);
93 static ssize_t cur_speed_read_file(struct pci_slot *slot, char *buf)
95 return bus_speed_read(slot->bus->cur_bus_speed, buf);
98 static void pci_slot_release(struct kobject *kobj)
101 struct pci_slot *slot = to_pci_slot(kobj);
103 dev_dbg(&slot->bus->dev, "dev %02x, released physical slot %s\n",
104 slot->number, pci_slot_name(slot));
106 list_for_each_entry(dev, &slot->bus->devices, bus_list)
107 if (PCI_SLOT(dev->devfn) == slot->number)
110 list_del(&slot->list);
115 static struct pci_slot_attribute pci_slot_attr_address =
116 __ATTR(address, (S_IFREG | S_IRUGO), address_read_file, NULL);
117 static struct pci_slot_attribute pci_slot_attr_max_speed =
118 __ATTR(max_bus_speed, (S_IFREG | S_IRUGO), max_speed_read_file, NULL);
119 static struct pci_slot_attribute pci_slot_attr_cur_speed =
120 __ATTR(cur_bus_speed, (S_IFREG | S_IRUGO), cur_speed_read_file, NULL);
122 static struct attribute *pci_slot_default_attrs[] = {
123 &pci_slot_attr_address.attr,
124 &pci_slot_attr_max_speed.attr,
125 &pci_slot_attr_cur_speed.attr,
129 static struct kobj_type pci_slot_ktype = {
130 .sysfs_ops = &pci_slot_sysfs_ops,
131 .release = &pci_slot_release,
132 .default_attrs = pci_slot_default_attrs,
135 static char *make_slot_name(const char *name)
140 new_name = kstrdup(name, GFP_KERNEL);
145 * Make sure we hit the realloc case the first time through the
146 * loop. 'len' will be strlen(name) + 3 at that point which is
147 * enough space for "name-X" and the trailing NUL.
149 len = strlen(name) + 2;
154 struct kobject *dup_slot;
155 dup_slot = kset_find_obj(pci_slots_kset, new_name);
158 kobject_put(dup_slot);
163 new_name = kmalloc(len, GFP_KERNEL);
167 sprintf(new_name, "%s-%d", name, dup++);
173 static int rename_slot(struct pci_slot *slot, const char *name)
178 if (strcmp(pci_slot_name(slot), name) == 0)
181 slot_name = make_slot_name(name);
185 result = kobject_rename(&slot->kobj, slot_name);
191 static struct pci_slot *get_slot(struct pci_bus *parent, int slot_nr)
193 struct pci_slot *slot;
195 * We already hold pci_bus_sem so don't worry
197 list_for_each_entry(slot, &parent->slots, list)
198 if (slot->number == slot_nr) {
199 kobject_get(&slot->kobj);
207 * pci_create_slot - create or increment refcount for physical PCI slot
208 * @parent: struct pci_bus of parent bridge
209 * @slot_nr: PCI_SLOT(pci_dev->devfn) or -1 for placeholder
210 * @name: user visible string presented in /sys/bus/pci/slots/<name>
211 * @hotplug: set if caller is hotplug driver, NULL otherwise
213 * PCI slots have first class attributes such as address, speed, width,
214 * and a &struct pci_slot is used to manage them. This interface will
215 * either return a new &struct pci_slot to the caller, or if the pci_slot
216 * already exists, its refcount will be incremented.
218 * Slots are uniquely identified by a @pci_bus, @slot_nr tuple.
220 * There are known platforms with broken firmware that assign the same
221 * name to multiple slots. Workaround these broken platforms by renaming
222 * the slots on behalf of the caller. If firmware assigns name N to
225 * The first slot is assigned N
226 * The second slot is assigned N-1
227 * The third slot is assigned N-2
231 * In most cases, @pci_bus, @slot_nr will be sufficient to uniquely identify
232 * a slot. There is one notable exception - pSeries (rpaphp), where the
233 * @slot_nr cannot be determined until a device is actually inserted into
234 * the slot. In this scenario, the caller may pass -1 for @slot_nr.
236 * The following semantics are imposed when the caller passes @slot_nr ==
237 * -1. First, we no longer check for an existing %struct pci_slot, as there
238 * may be many slots with @slot_nr of -1. The other change in semantics is
239 * user-visible, which is the 'address' parameter presented in sysfs will
240 * consist solely of a dddd:bb tuple, where dddd is the PCI domain of the
241 * %struct pci_bus and bb is the bus number. In other words, the devfn of
242 * the 'placeholder' slot will not be displayed.
244 struct pci_slot *pci_create_slot(struct pci_bus *parent, int slot_nr,
246 struct hotplug_slot *hotplug)
249 struct pci_slot *slot;
251 char *slot_name = NULL;
253 down_write(&pci_bus_sem);
259 * Hotplug drivers are allowed to rename an existing slot,
260 * but only if not already claimed.
262 slot = get_slot(parent, slot_nr);
265 if ((err = slot->hotplug ? -EBUSY : 0)
266 || (err = rename_slot(slot, name))) {
267 kobject_put(&slot->kobj);
276 slot = kzalloc(sizeof(*slot), GFP_KERNEL);
283 slot->number = slot_nr;
285 slot->kobj.kset = pci_slots_kset;
287 slot_name = make_slot_name(name);
293 err = kobject_init_and_add(&slot->kobj, &pci_slot_ktype, NULL,
298 INIT_LIST_HEAD(&slot->list);
299 list_add(&slot->list, &parent->slots);
301 list_for_each_entry(dev, &parent->devices, bus_list)
302 if (PCI_SLOT(dev->devfn) == slot_nr)
305 dev_dbg(&parent->dev, "dev %02x, created physical slot %s\n",
306 slot_nr, pci_slot_name(slot));
310 up_write(&pci_bus_sem);
317 EXPORT_SYMBOL_GPL(pci_create_slot);
320 * pci_renumber_slot - update %struct pci_slot -> number
321 * @slot: &struct pci_slot to update
322 * @slot_nr: new number for slot
324 * The primary purpose of this interface is to allow callers who earlier
325 * created a placeholder slot in pci_create_slot() by passing a -1 as
326 * slot_nr, to update their %struct pci_slot with the correct @slot_nr.
328 void pci_renumber_slot(struct pci_slot *slot, int slot_nr)
330 struct pci_slot *tmp;
332 down_write(&pci_bus_sem);
334 list_for_each_entry(tmp, &slot->bus->slots, list) {
335 WARN_ON(tmp->number == slot_nr);
339 slot->number = slot_nr;
341 up_write(&pci_bus_sem);
343 EXPORT_SYMBOL_GPL(pci_renumber_slot);
346 * pci_destroy_slot - decrement refcount for physical PCI slot
347 * @slot: struct pci_slot to decrement
349 * %struct pci_slot is refcounted, so destroying them is really easy; we
350 * just call kobject_put on its kobj and let our release methods do the
353 void pci_destroy_slot(struct pci_slot *slot)
355 dev_dbg(&slot->bus->dev, "dev %02x, dec refcount to %d\n",
356 slot->number, atomic_read(&slot->kobj.kref.refcount) - 1);
358 down_write(&pci_bus_sem);
359 kobject_put(&slot->kobj);
360 up_write(&pci_bus_sem);
362 EXPORT_SYMBOL_GPL(pci_destroy_slot);
364 #if defined(CONFIG_HOTPLUG_PCI) || defined(CONFIG_HOTPLUG_PCI_MODULE)
365 #include <linux/pci_hotplug.h>
367 * pci_hp_create_link - create symbolic link to the hotplug driver module.
368 * @pci_slot: struct pci_slot
370 * Helper function for pci_hotplug_core.c to create symbolic link to
371 * the hotplug driver module.
373 void pci_hp_create_module_link(struct pci_slot *pci_slot)
375 struct hotplug_slot *slot = pci_slot->hotplug;
376 struct kobject *kobj = NULL;
379 if (!slot || !slot->ops)
381 kobj = kset_find_obj(module_kset, slot->ops->mod_name);
384 no_warn = sysfs_create_link(&pci_slot->kobj, kobj, "module");
387 EXPORT_SYMBOL_GPL(pci_hp_create_module_link);
390 * pci_hp_remove_link - remove symbolic link to the hotplug driver module.
391 * @pci_slot: struct pci_slot
393 * Helper function for pci_hotplug_core.c to remove symbolic link to
394 * the hotplug driver module.
396 void pci_hp_remove_module_link(struct pci_slot *pci_slot)
398 sysfs_remove_link(&pci_slot->kobj, "module");
400 EXPORT_SYMBOL_GPL(pci_hp_remove_module_link);
403 static int pci_slot_init(void)
405 struct kset *pci_bus_kset;
407 pci_bus_kset = bus_get_kset(&pci_bus_type);
408 pci_slots_kset = kset_create_and_add("slots", NULL,
409 &pci_bus_kset->kobj);
410 if (!pci_slots_kset) {
411 printk(KERN_ERR "PCI: Slot initialization failure\n");
417 subsys_initcall(pci_slot_init);