/*
* PCI searching functions.
*
- * Copyright 1993 -- 1997 Drew Eckhardt, Frederic Potter,
- * David Mosberger-Tang
- * Copyright 1997 -- 2000 Martin Mares <mj@ucw.cz>
- * Copyright 2003 -- Greg Kroah-Hartman <greg@kroah.com>
+ * Copyright (C) 1993 -- 1997 Drew Eckhardt, Frederic Potter,
+ * David Mosberger-Tang
+ * Copyright (C) 1997 -- 2000 Martin Mares <mj@ucw.cz>
+ * Copyright (C) 2003 -- 2004 Greg Kroah-Hartman <greg@kroah.com>
*/
#include <linux/init.h>
#include <linux/pci.h>
#include <linux/module.h>
#include <linux/interrupt.h>
+#include "pci.h"
-spinlock_t pci_bus_lock = SPIN_LOCK_UNLOCKED;
+DECLARE_RWSEM(pci_bus_sem);
static struct pci_bus * __devinit
pci_do_find_bus(struct pci_bus* bus, unsigned char busnr)
* in the global list of PCI buses. If the bus is found, a pointer to its
* data structure is returned. If no bus is found, %NULL is returned.
*/
-struct pci_bus * __devinit pci_find_bus(int domain, int busnr)
+struct pci_bus * pci_find_bus(int domain, int busnr)
{
struct pci_bus *bus = NULL;
struct pci_bus *tmp_bus;
* @from: Previous PCI bus found, or %NULL for new search.
*
* Iterates through the list of known PCI busses. A new search is
- * initiated by passing %NULL to the @from argument. Otherwise if
+ * initiated by passing %NULL as the @from argument. Otherwise if
* @from is not %NULL, searches continue from next device on the
* global list.
*/
struct pci_bus *b = NULL;
WARN_ON(in_interrupt());
- spin_lock(&pci_bus_lock);
+ down_read(&pci_bus_sem);
n = from ? from->node.next : pci_root_buses.next;
if (n != &pci_root_buses)
b = pci_bus_b(n);
- spin_unlock(&pci_bus_lock);
+ up_read(&pci_bus_sem);
return b;
}
struct pci_dev *dev;
WARN_ON(in_interrupt());
- spin_lock(&pci_bus_lock);
+ down_read(&pci_bus_sem);
list_for_each(tmp, &bus->devices) {
dev = pci_dev_b(tmp);
dev = NULL;
out:
pci_dev_get(dev);
- spin_unlock(&pci_bus_lock);
+ up_read(&pci_bus_sem);
return dev;
}
+/**
+ * pci_get_bus_and_slot - locate PCI device from a given PCI slot
+ * @bus: number of PCI bus on which desired PCI device resides
+ * @devfn: encodes number of PCI slot in which the desired PCI
+ * device resides and the logical device number within that slot
+ * in case of multi-function devices.
+ *
+ * Given a PCI bus and slot/function number, the desired PCI device
+ * is located in system global list of PCI devices. If the device
+ * is found, a pointer to its data structure is returned. If no
+ * device is found, %NULL is returned. The returned device has its
+ * reference count bumped by one.
+ */
+
+struct pci_dev * pci_get_bus_and_slot(unsigned int bus, unsigned int devfn)
+{
+ struct pci_dev *dev = NULL;
+
+ while ((dev = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, dev)) != NULL) {
+ if (dev->bus->number == bus && dev->devfn == devfn)
+ return dev;
+ }
+ return NULL;
+}
+
/**
* pci_find_subsys - begin or continue searching for a PCI device by vendor/subvendor/device/subdevice id
* @vendor: PCI vendor id to match, or %PCI_ANY_ID to match all vendor ids
* @from: Previous PCI device found in search, or %NULL for new search.
*
* Iterates through the list of known PCI devices. If a PCI device is
- * found with a matching @vendor, @device, @ss_vendor and @ss_device, a pointer to its
- * device structure is returned. Otherwise, %NULL is returned.
- * A new search is initiated by passing %NULL to the @from argument.
- * Otherwise if @from is not %NULL, searches continue from next device on the global list.
+ * found with a matching @vendor, @device, @ss_vendor and @ss_device, a
+ * pointer to its device structure is returned. Otherwise, %NULL is returned.
+ * A new search is initiated by passing %NULL as the @from argument.
+ * Otherwise if @from is not %NULL, searches continue from next device
+ * on the global list.
*
- * NOTE: Do not use this function anymore, use pci_get_subsys() instead, as
- * the pci device returned by this function can disappear at any moment in
+ * NOTE: Do not use this function any more; use pci_get_subsys() instead, as
+ * the PCI device returned by this function can disappear at any moment in
* time.
*/
-struct pci_dev *
-pci_find_subsys(unsigned int vendor, unsigned int device,
- unsigned int ss_vendor, unsigned int ss_device,
- const struct pci_dev *from)
+static struct pci_dev * pci_find_subsys(unsigned int vendor,
+ unsigned int device,
+ unsigned int ss_vendor,
+ unsigned int ss_device,
+ const struct pci_dev *from)
{
struct list_head *n;
struct pci_dev *dev;
WARN_ON(in_interrupt());
- spin_lock(&pci_bus_lock);
+
+ /*
+ * pci_find_subsys() can be called on the ide_setup() path, super-early
+ * in boot. But the down_read() will enable local interrupts, which
+ * can cause some machines to crash. So here we detect and flag that
+ * situation and bail out early.
+ */
+ if (unlikely(list_empty(&pci_devices)))
+ return NULL;
+ down_read(&pci_bus_sem);
n = from ? from->global_list.next : pci_devices.next;
while (n && (n != &pci_devices)) {
}
dev = NULL;
exit:
- spin_unlock(&pci_bus_lock);
+ up_read(&pci_bus_sem);
return dev;
}
* @device: PCI device id to match, or %PCI_ANY_ID to match all device ids
* @from: Previous PCI device found in search, or %NULL for new search.
*
- * Iterates through the list of known PCI devices. If a PCI device is
- * found with a matching @vendor and @device, a pointer to its device structure is
+ * Iterates through the list of known PCI devices. If a PCI device is found
+ * with a matching @vendor and @device, a pointer to its device structure is
* returned. Otherwise, %NULL is returned.
- * A new search is initiated by passing %NULL to the @from argument.
- * Otherwise if @from is not %NULL, searches continue from next device on the global list.
+ * A new search is initiated by passing %NULL as the @from argument.
+ * Otherwise if @from is not %NULL, searches continue from next device
+ * on the global list.
*
- * NOTE: Do not use this function anymore, use pci_get_device() instead, as
- * the pci device returned by this function can disappear at any moment in
+ * NOTE: Do not use this function any more; use pci_get_device() instead, as
+ * the PCI device returned by this function can disappear at any moment in
* time.
*/
struct pci_dev *
* @ss_device: PCI subsystem device id to match, or %PCI_ANY_ID to match all device ids
* @from: Previous PCI device found in search, or %NULL for new search.
*
- * Iterates through the list of known PCI devices. If a PCI device is
- * found with a matching @vendor, @device, @ss_vendor and @ss_device, a pointer to its
+ * Iterates through the list of known PCI devices. If a PCI device is found
+ * with a matching @vendor, @device, @ss_vendor and @ss_device, a pointer to its
* device structure is returned, and the reference count to the device is
* incremented. Otherwise, %NULL is returned. A new search is initiated by
- * passing %NULL to the @from argument. Otherwise if @from is not %NULL,
+ * passing %NULL as the @from argument. Otherwise if @from is not %NULL,
* searches continue from next device on the global list.
* The reference count for @from is always decremented if it is not %NULL.
*/
struct pci_dev *dev;
WARN_ON(in_interrupt());
- spin_lock(&pci_bus_lock);
+
+ /*
+ * pci_get_subsys() can potentially be called by drivers super-early
+ * in boot. But the down_read() will enable local interrupts, which
+ * can cause some machines to crash. So here we detect and flag that
+ * situation and bail out early.
+ */
+ if (unlikely(list_empty(&pci_devices)))
+ return NULL;
+ down_read(&pci_bus_sem);
n = from ? from->global_list.next : pci_devices.next;
while (n && (n != &pci_devices)) {
}
dev = NULL;
exit:
- pci_dev_put(from);
dev = pci_dev_get(dev);
- spin_unlock(&pci_bus_lock);
+ up_read(&pci_bus_sem);
+ pci_dev_put(from);
return dev;
}
* @from: Previous PCI device found in search, or %NULL for new search.
*
* Iterates through the list of known PCI devices. If a PCI device is
- * found with a matching @vendor and @device, a pointer to its device structure is
- * returned. Otherwise, %NULL is returned.
- * A new search is initiated by passing %NULL to the @from argument.
- * Otherwise if @from is not %NULL, searches continue from next device on the global list.
- *
- * Iterates through the list of known PCI devices. If a PCI device is
* found with a matching @vendor and @device, the reference count to the
* device is incremented and a pointer to its device structure is returned.
* Otherwise, %NULL is returned. A new search is initiated by passing %NULL
- * to the @from argument. Otherwise if @from is not %NULL, searches continue
+ * as the @from argument. Otherwise if @from is not %NULL, searches continue
* from next device on the global list. The reference count for @from is
* always decremented if it is not %NULL.
*/
return pci_get_subsys(vendor, device, PCI_ANY_ID, PCI_ANY_ID, from);
}
+/**
+ * pci_get_device_reverse - begin or continue searching for a PCI device by vendor/device id
+ * @vendor: PCI vendor id to match, or %PCI_ANY_ID to match all vendor ids
+ * @device: PCI device id to match, or %PCI_ANY_ID to match all device ids
+ * @from: Previous PCI device found in search, or %NULL for new search.
+ *
+ * Iterates through the list of known PCI devices in the reverse order of
+ * pci_get_device.
+ * If a PCI device is found with a matching @vendor and @device, the reference
+ * count to the device is incremented and a pointer to its device structure
+ * is returned Otherwise, %NULL is returned. A new search is initiated by
+ * passing %NULL as the @from argument. Otherwise if @from is not %NULL,
+ * searches continue from next device on the global list. The reference
+ * count for @from is always decremented if it is not %NULL.
+ */
+struct pci_dev *
+pci_get_device_reverse(unsigned int vendor, unsigned int device, struct pci_dev *from)
+{
+ struct list_head *n;
+ struct pci_dev *dev;
+
+ WARN_ON(in_interrupt());
+ down_read(&pci_bus_sem);
+ n = from ? from->global_list.prev : pci_devices.prev;
+
+ while (n && (n != &pci_devices)) {
+ dev = pci_dev_g(n);
+ if ((vendor == PCI_ANY_ID || dev->vendor == vendor) &&
+ (device == PCI_ANY_ID || dev->device == device))
+ goto exit;
+ n = n->prev;
+ }
+ dev = NULL;
+exit:
+ dev = pci_dev_get(dev);
+ up_read(&pci_bus_sem);
+ pci_dev_put(from);
+ return dev;
+}
/**
* pci_find_device_reverse - begin or continue searching for a PCI device by vendor/device id
* @device: PCI device id to match, or %PCI_ANY_ID to match all device ids
* @from: Previous PCI device found in search, or %NULL for new search.
*
- * Iterates through the list of known PCI devices in the reverse order of pci_find_device().
+ * Iterates through the list of known PCI devices in the reverse order of
+ * pci_find_device().
* If a PCI device is found with a matching @vendor and @device, a pointer to
* its device structure is returned. Otherwise, %NULL is returned.
- * A new search is initiated by passing %NULL to the @from argument.
- * Otherwise if @from is not %NULL, searches continue from previous device on the global list.
+ * A new search is initiated by passing %NULL as the @from argument.
+ * Otherwise if @from is not %NULL, searches continue from previous device
+ * on the global list.
*/
struct pci_dev *
pci_find_device_reverse(unsigned int vendor, unsigned int device, const struct pci_dev *from)
struct pci_dev *dev;
WARN_ON(in_interrupt());
- spin_lock(&pci_bus_lock);
+ down_read(&pci_bus_sem);
n = from ? from->global_list.prev : pci_devices.prev;
while (n && (n != &pci_devices)) {
}
dev = NULL;
exit:
- spin_unlock(&pci_bus_lock);
+ up_read(&pci_bus_sem);
return dev;
}
-
/**
- * pci_find_class - begin or continue searching for a PCI device by class
+ * pci_get_class - begin or continue searching for a PCI device by class
* @class: search for a PCI device with this class designation
* @from: Previous PCI device found in search, or %NULL for new search.
*
* Iterates through the list of known PCI devices. If a PCI device is
- * found with a matching @class, a pointer to its device structure is
- * returned. Otherwise, %NULL is returned.
- * A new search is initiated by passing %NULL to the @from argument.
+ * found with a matching @class, the reference count to the device is
+ * incremented and a pointer to its device structure is returned.
+ * Otherwise, %NULL is returned.
+ * A new search is initiated by passing %NULL as the @from argument.
* Otherwise if @from is not %NULL, searches continue from next device
- * on the global list.
+ * on the global list. The reference count for @from is always decremented
+ * if it is not %NULL.
*/
-struct pci_dev *
-pci_find_class(unsigned int class, const struct pci_dev *from)
+struct pci_dev *pci_get_class(unsigned int class, struct pci_dev *from)
{
struct list_head *n;
struct pci_dev *dev;
- spin_lock(&pci_bus_lock);
+ WARN_ON(in_interrupt());
+ down_read(&pci_bus_sem);
n = from ? from->global_list.next : pci_devices.next;
while (n && (n != &pci_devices)) {
}
dev = NULL;
exit:
- spin_unlock(&pci_bus_lock);
+ dev = pci_dev_get(dev);
+ up_read(&pci_bus_sem);
+ pci_dev_put(from);
return dev;
}
-EXPORT_SYMBOL(pci_find_bus);
-EXPORT_SYMBOL(pci_find_class);
+const struct pci_device_id *pci_find_present(const struct pci_device_id *ids)
+{
+ struct pci_dev *dev;
+ const struct pci_device_id *found = NULL;
+
+ WARN_ON(in_interrupt());
+ down_read(&pci_bus_sem);
+ while (ids->vendor || ids->subvendor || ids->class_mask) {
+ list_for_each_entry(dev, &pci_devices, global_list) {
+ if ((found = pci_match_one_device(ids, dev)) != NULL)
+ break;
+ }
+ ids++;
+ }
+ up_read(&pci_bus_sem);
+ return found;
+}
+
+/**
+ * pci_dev_present - Returns 1 if device matching the device list is present, 0 if not.
+ * @ids: A pointer to a null terminated list of struct pci_device_id structures
+ * that describe the type of PCI device the caller is trying to find.
+ *
+ * Obvious fact: You do not have a reference to any device that might be found
+ * by this function, so if that device is removed from the system right after
+ * this function is finished, the value will be stale. Use this function to
+ * find devices that are usually built into a system, or for a general hint as
+ * to if another device happens to be present at this specific moment in time.
+ */
+int pci_dev_present(const struct pci_device_id *ids)
+{
+ return pci_find_present(ids) == NULL ? 0 : 1;
+}
+
+EXPORT_SYMBOL(pci_dev_present);
+EXPORT_SYMBOL(pci_find_present);
+
EXPORT_SYMBOL(pci_find_device);
EXPORT_SYMBOL(pci_find_device_reverse);
EXPORT_SYMBOL(pci_find_slot);
-EXPORT_SYMBOL(pci_find_subsys);
+/* For boot time work */
+EXPORT_SYMBOL(pci_find_bus);
+EXPORT_SYMBOL(pci_find_next_bus);
+/* For everyone */
EXPORT_SYMBOL(pci_get_device);
+EXPORT_SYMBOL(pci_get_device_reverse);
EXPORT_SYMBOL(pci_get_subsys);
EXPORT_SYMBOL(pci_get_slot);
+EXPORT_SYMBOL(pci_get_bus_and_slot);
+EXPORT_SYMBOL(pci_get_class);
git://git.onelab.eu / linux-2.6.git / blobdiff