Initial import

1 files changed, 386 insertions, 0 deletions

diff --git a/drivers/pci/search.c b/drivers/pci/search.c
new file mode 100644
index 000000000..a20ce7d5e
--- /dev/null
+++ b/drivers/pci/search.c
@@ -0,0 +1,386 @@
+/*
+ *	PCI searching functions.
+ *
+ *	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/pci.h>
+#include <linux/slab.h>
+#include <linux/module.h>
+#include <linux/interrupt.h>
+#include "pci.h"
+
+DECLARE_RWSEM(pci_bus_sem);
+EXPORT_SYMBOL_GPL(pci_bus_sem);
+
+/*
+ * pci_for_each_dma_alias - Iterate over DMA aliases for a device
+ * @pdev: starting downstream device
+ * @fn: function to call for each alias
+ * @data: opaque data to pass to @fn
+ *
+ * Starting @pdev, walk up the bus calling @fn for each possible alias
+ * of @pdev at the root bus.
+ */
+int pci_for_each_dma_alias(struct pci_dev *pdev,
+			   int (*fn)(struct pci_dev *pdev,
+				     u16 alias, void *data), void *data)
+{
+	struct pci_bus *bus;
+	int ret;
+
+	ret = fn(pdev, PCI_DEVID(pdev->bus->number, pdev->devfn), data);
+	if (ret)
+		return ret;
+
+	/*
+	 * If the device is broken and uses an alias requester ID for
+	 * DMA, iterate over that too.
+	 */
+	if (unlikely(pdev->dev_flags & PCI_DEV_FLAGS_DMA_ALIAS_DEVFN)) {
+		ret = fn(pdev, PCI_DEVID(pdev->bus->number,
+					 pdev->dma_alias_devfn), data);
+		if (ret)
+			return ret;
+	}
+
+	for (bus = pdev->bus; !pci_is_root_bus(bus); bus = bus->parent) {
+		struct pci_dev *tmp;
+
+		/* Skip virtual buses */
+		if (!bus->self)
+			continue;
+
+		tmp = bus->self;
+
+		/*
+		 * PCIe-to-PCI/X bridges alias transactions from downstream
+		 * devices using the subordinate bus number (PCI Express to
+		 * PCI/PCI-X Bridge Spec, rev 1.0, sec 2.3).  For all cases
+		 * where the upstream bus is PCI/X we alias to the bridge
+		 * (there are various conditions in the previous reference
+		 * where the bridge may take ownership of transactions, even
+		 * when the secondary interface is PCI-X).
+		 */
+		if (pci_is_pcie(tmp)) {
+			switch (pci_pcie_type(tmp)) {
+			case PCI_EXP_TYPE_ROOT_PORT:
+			case PCI_EXP_TYPE_UPSTREAM:
+			case PCI_EXP_TYPE_DOWNSTREAM:
+				continue;
+			case PCI_EXP_TYPE_PCI_BRIDGE:
+				ret = fn(tmp,
+					 PCI_DEVID(tmp->subordinate->number,
+						   PCI_DEVFN(0, 0)), data);
+				if (ret)
+					return ret;
+				continue;
+			case PCI_EXP_TYPE_PCIE_BRIDGE:
+				ret = fn(tmp,
+					 PCI_DEVID(tmp->bus->number,
+						   tmp->devfn), data);
+				if (ret)
+					return ret;
+				continue;
+			}
+		} else {
+			if (tmp->dev_flags & PCI_DEV_FLAG_PCIE_BRIDGE_ALIAS)
+				ret = fn(tmp,
+					 PCI_DEVID(tmp->subordinate->number,
+						   PCI_DEVFN(0, 0)), data);
+			else
+				ret = fn(tmp,
+					 PCI_DEVID(tmp->bus->number,
+						   tmp->devfn), data);
+			if (ret)
+				return ret;
+		}
+	}
+
+	return ret;
+}
+
+static struct pci_bus *pci_do_find_bus(struct pci_bus *bus, unsigned char busnr)
+{
+	struct pci_bus *child;
+	struct pci_bus *tmp;
+
+	if (bus->number == busnr)
+		return bus;
+
+	list_for_each_entry(tmp, &bus->children, node) {
+		child = pci_do_find_bus(tmp, busnr);
+		if (child)
+			return child;
+	}
+	return NULL;
+}
+
+/**
+ * pci_find_bus - locate PCI bus from a given domain and bus number
+ * @domain: number of PCI domain to search
+ * @busnr: number of desired PCI bus
+ *
+ * Given a PCI bus number and domain number, the desired PCI bus is located
+ * 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 *pci_find_bus(int domain, int busnr)
+{
+	struct pci_bus *bus = NULL;
+	struct pci_bus *tmp_bus;
+
+	while ((bus = pci_find_next_bus(bus)) != NULL)  {
+		if (pci_domain_nr(bus) != domain)
+			continue;
+		tmp_bus = pci_do_find_bus(bus, busnr);
+		if (tmp_bus)
+			return tmp_bus;
+	}
+	return NULL;
+}
+EXPORT_SYMBOL(pci_find_bus);
+
+/**
+ * pci_find_next_bus - begin or continue searching for a PCI bus
+ * @from: Previous PCI bus found, or %NULL for new search.
+ *
+ * Iterates through the list of known PCI buses.  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.
+ */
+struct pci_bus *pci_find_next_bus(const struct pci_bus *from)
+{
+	struct list_head *n;
+	struct pci_bus *b = NULL;
+
+	WARN_ON(in_interrupt());
+	down_read(&pci_bus_sem);
+	n = from ? from->node.next : pci_root_buses.next;
+	if (n != &pci_root_buses)
+		b = list_entry(n, struct pci_bus, node);
+	up_read(&pci_bus_sem);
+	return b;
+}
+EXPORT_SYMBOL(pci_find_next_bus);
+
+/**
+ * pci_get_slot - locate PCI device for a given PCI slot
+ * @bus: 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 the list of PCI devices.
+ * If the device is found, its reference count is increased and this
+ * function returns a pointer to its data structure.  The caller must
+ * decrement the reference count by calling pci_dev_put().
+ * If no device is found, %NULL is returned.
+ */
+struct pci_dev *pci_get_slot(struct pci_bus *bus, unsigned int devfn)
+{
+	struct pci_dev *dev;
+
+	WARN_ON(in_interrupt());
+	down_read(&pci_bus_sem);
+
+	list_for_each_entry(dev, &bus->devices, bus_list) {
+		if (dev->devfn == devfn)
+			goto out;
+	}
+
+	dev = NULL;
+ out:
+	pci_dev_get(dev);
+	up_read(&pci_bus_sem);
+	return dev;
+}
+EXPORT_SYMBOL(pci_get_slot);
+
+/**
+ * pci_get_domain_bus_and_slot - locate PCI device for a given PCI domain (segment), bus, and slot
+ * @domain: PCI domain/segment on which the PCI device resides.
+ * @bus: 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 domain, bus, and slot/function number, the desired PCI
+ * device is located in the list of PCI devices. If the device is
+ * found, its reference count is increased and this function returns a
+ * pointer to its data structure.  The caller must decrement the
+ * reference count by calling pci_dev_put().  If no device is found,
+ * %NULL is returned.
+ */
+struct pci_dev *pci_get_domain_bus_and_slot(int domain, unsigned int bus,
+					    unsigned int devfn)
+{
+	struct pci_dev *dev = NULL;
+
+	for_each_pci_dev(dev) {
+		if (pci_domain_nr(dev->bus) == domain &&
+		    (dev->bus->number == bus && dev->devfn == devfn))
+			return dev;
+	}
+	return NULL;
+}
+EXPORT_SYMBOL(pci_get_domain_bus_and_slot);
+
+static int match_pci_dev_by_id(struct device *dev, void *data)
+{
+	struct pci_dev *pdev = to_pci_dev(dev);
+	struct pci_device_id *id = data;
+
+	if (pci_match_one_device(id, pdev))
+		return 1;
+	return 0;
+}
+
+/*
+ * pci_get_dev_by_id - begin or continue searching for a PCI device by id
+ * @id: pointer to struct pci_device_id to match for the device
+ * @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 id 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 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.
+ *
+ * This is an internal function for use by the other search functions in
+ * this file.
+ */
+static struct pci_dev *pci_get_dev_by_id(const struct pci_device_id *id,
+					 struct pci_dev *from)
+{
+	struct device *dev;
+	struct device *dev_start = NULL;
+	struct pci_dev *pdev = NULL;
+
+	WARN_ON(in_interrupt());
+	if (from)
+		dev_start = &from->dev;
+	dev = bus_find_device(&pci_bus_type, dev_start, (void *)id,
+			      match_pci_dev_by_id);
+	if (dev)
+		pdev = to_pci_dev(dev);
+	pci_dev_put(from);
+	return pdev;
+}
+
+/**
+ * pci_get_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
+ * @device: PCI device id to match, or %PCI_ANY_ID to match all device ids
+ * @ss_vendor: PCI subsystem vendor id to match, or %PCI_ANY_ID to match all vendor ids
+ * @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
+ * 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 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_subsys(unsigned int vendor, unsigned int device,
+			       unsigned int ss_vendor, unsigned int ss_device,
+			       struct pci_dev *from)
+{
+	struct pci_device_id id = {
+		.vendor = vendor,
+		.device = device,
+		.subvendor = ss_vendor,
+		.subdevice = ss_device,
+	};
+
+	return pci_get_dev_by_id(&id, from);
+}
+EXPORT_SYMBOL(pci_get_subsys);
+
+/**
+ * pci_get_device - 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.  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(unsigned int vendor, unsigned int device,
+			       struct pci_dev *from)
+{
+	return pci_get_subsys(vendor, device, PCI_ANY_ID, PCI_ANY_ID, from);
+}
+EXPORT_SYMBOL(pci_get_device);
+
+/**
+ * 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, 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_class(unsigned int class, struct pci_dev *from)
+{
+	struct pci_device_id id = {
+		.vendor = PCI_ANY_ID,
+		.device = PCI_ANY_ID,
+		.subvendor = PCI_ANY_ID,
+		.subdevice = PCI_ANY_ID,
+		.class_mask = PCI_ANY_ID,
+		.class = class,
+	};
+
+	return pci_get_dev_by_id(&id, from);
+}
+EXPORT_SYMBOL(pci_get_class);
+
+/**
+ * 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)
+{
+	struct pci_dev *found = NULL;
+
+	WARN_ON(in_interrupt());
+	while (ids->vendor || ids->subvendor || ids->class_mask) {
+		found = pci_get_dev_by_id(ids, NULL);
+		if (found) {
+			pci_dev_put(found);
+			return 1;
+		}
+		ids++;
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL(pci_dev_present);