From 29f3eb64634cf96903a3cdb56b1f9a80bebad17d Mon Sep 17 00:00:00 2001 From: Alan Cox Date: Mon, 16 Oct 2006 16:20:21 -0700 Subject: pci: Additional search functions In order to finish converting to pci_get_* interfaces we need to add a couple of bits of missing functionaility pci_get_bus_and_slot() provides the equivalent to pci_find_slot() (pci_get_slot is already taken as a name for something similar but not the same) pci_get_device_reverse() is the equivalent of pci_find_device_reverse but refcounting Signed-off-by: Alan Cox Signed-off-by: Andrew Morton Signed-off-by: Greg Kroah-Hartman --- drivers/pci/search.c | 72 ++++++++++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 70 insertions(+), 2 deletions(-) (limited to 'drivers/pci/search.c') diff --git a/drivers/pci/search.c b/drivers/pci/search.c index d529462d1b53..2f13eba5d5ae 100644 --- a/drivers/pci/search.c +++ b/drivers/pci/search.c @@ -139,6 +139,31 @@ struct pci_dev * pci_get_slot(struct pci_bus *bus, unsigned int devfn) 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 @@ -274,6 +299,45 @@ pci_get_device(unsigned int vendor, unsigned int device, struct pci_dev *from) 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 @@ -382,12 +446,16 @@ exit: } EXPORT_SYMBOL(pci_dev_present); -EXPORT_SYMBOL(pci_find_bus); -EXPORT_SYMBOL(pci_find_next_bus); EXPORT_SYMBOL(pci_find_device); EXPORT_SYMBOL(pci_find_device_reverse); EXPORT_SYMBOL(pci_find_slot); +/* 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); -- cgit v1.2.3-58-ga151