kernel-ark/drivers/pci/bus.c
Greg Kroah-Hartman fd7d1ced29 PCI: make pci_bus a struct device
This moves the pci_bus class device to be a real struct device and at
the same time, place it in the device tree in the correct location.

Note, the old "bridge" symlink is now gone, but this was a non-standard
link and no userspace program used it.  If you need to determine the
device that the bus is on, follow the standard device symlink, or walk
up the device tree.


Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-02-01 15:04:31 -08:00

221 lines
5.6 KiB
C

/*
* drivers/pci/bus.c
*
* From setup-res.c, by:
* Dave Rusling (david.rusling@reo.mts.dec.com)
* David Mosberger (davidm@cs.arizona.edu)
* David Miller (davem@redhat.com)
* Ivan Kokshaysky (ink@jurassic.park.msu.ru)
*/
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/pci.h>
#include <linux/errno.h>
#include <linux/ioport.h>
#include <linux/proc_fs.h>
#include <linux/init.h>
#include "pci.h"
/**
* pci_bus_alloc_resource - allocate a resource from a parent bus
* @bus: PCI bus
* @res: resource to allocate
* @size: size of resource to allocate
* @align: alignment of resource to allocate
* @min: minimum /proc/iomem address to allocate
* @type_mask: IORESOURCE_* type flags
* @alignf: resource alignment function
* @alignf_data: data argument for resource alignment function
*
* Given the PCI bus a device resides on, the size, minimum address,
* alignment and type, try to find an acceptable resource allocation
* for a specific device resource.
*/
int
pci_bus_alloc_resource(struct pci_bus *bus, struct resource *res,
resource_size_t size, resource_size_t align,
resource_size_t min, unsigned int type_mask,
void (*alignf)(void *, struct resource *, resource_size_t,
resource_size_t),
void *alignf_data)
{
int i, ret = -ENOMEM;
type_mask |= IORESOURCE_IO | IORESOURCE_MEM;
for (i = 0; i < PCI_BUS_NUM_RESOURCES; i++) {
struct resource *r = bus->resource[i];
if (!r)
continue;
/* type_mask must match */
if ((res->flags ^ r->flags) & type_mask)
continue;
/* We cannot allocate a non-prefetching resource
from a pre-fetching area */
if ((r->flags & IORESOURCE_PREFETCH) &&
!(res->flags & IORESOURCE_PREFETCH))
continue;
/* Ok, try it out.. */
ret = allocate_resource(r, res, size,
r->start ? : min,
-1, align,
alignf, alignf_data);
if (ret == 0)
break;
}
return ret;
}
/**
* add a single device
* @dev: device to add
*
* This adds a single pci device to the global
* device list and adds sysfs and procfs entries
*/
int pci_bus_add_device(struct pci_dev *dev)
{
int retval;
retval = device_add(&dev->dev);
if (retval)
return retval;
down_write(&pci_bus_sem);
list_add_tail(&dev->global_list, &pci_devices);
up_write(&pci_bus_sem);
pci_proc_attach_device(dev);
pci_create_sysfs_dev_files(dev);
return 0;
}
/**
* pci_bus_add_devices - insert newly discovered PCI devices
* @bus: bus to check for new devices
*
* Add newly discovered PCI devices (which are on the bus->devices
* list) to the global PCI device list, add the sysfs and procfs
* entries. Where a bridge is found, add the discovered bus to
* the parents list of child buses, and recurse (breadth-first
* to be compatible with 2.4)
*
* Call hotplug for each new devices.
*/
void pci_bus_add_devices(struct pci_bus *bus)
{
struct pci_dev *dev;
struct pci_bus *child_bus;
int retval;
list_for_each_entry(dev, &bus->devices, bus_list) {
/*
* Skip already-present devices (which are on the
* global device list.)
*/
if (!list_empty(&dev->global_list))
continue;
retval = pci_bus_add_device(dev);
if (retval)
dev_err(&dev->dev, "Error adding device, continuing\n");
}
list_for_each_entry(dev, &bus->devices, bus_list) {
BUG_ON(list_empty(&dev->global_list));
/*
* If there is an unattached subordinate bus, attach
* it and then scan for unattached PCI devices.
*/
if (dev->subordinate) {
if (list_empty(&dev->subordinate->node)) {
down_write(&pci_bus_sem);
list_add_tail(&dev->subordinate->node,
&dev->bus->children);
up_write(&pci_bus_sem);
}
pci_bus_add_devices(dev->subordinate);
/* register the bus with sysfs as the parent is now
* properly registered. */
child_bus = dev->subordinate;
child_bus->dev.parent = child_bus->bridge;
retval = device_register(&child_bus->dev);
if (!retval)
retval = device_create_file(&child_bus->dev,
&dev_attr_cpuaffinity);
if (retval)
dev_err(&dev->dev, "Error registering pci_bus"
" device bridge symlink,"
" continuing...\n");
}
}
}
void pci_enable_bridges(struct pci_bus *bus)
{
struct pci_dev *dev;
int retval;
list_for_each_entry(dev, &bus->devices, bus_list) {
if (dev->subordinate) {
retval = pci_enable_device(dev);
pci_set_master(dev);
pci_enable_bridges(dev->subordinate);
}
}
}
/** pci_walk_bus - walk devices on/under bus, calling callback.
* @top bus whose devices should be walked
* @cb callback to be called for each device found
* @userdata arbitrary pointer to be passed to callback.
*
* Walk the given bus, including any bridged devices
* on buses under this bus. Call the provided callback
* on each device found.
*/
void pci_walk_bus(struct pci_bus *top, void (*cb)(struct pci_dev *, void *),
void *userdata)
{
struct pci_dev *dev;
struct pci_bus *bus;
struct list_head *next;
bus = top;
down_read(&pci_bus_sem);
next = top->devices.next;
for (;;) {
if (next == &bus->devices) {
/* end of this bus, go up or finish */
if (bus == top)
break;
next = bus->self->bus_list.next;
bus = bus->self->bus;
continue;
}
dev = list_entry(next, struct pci_dev, bus_list);
if (dev->subordinate) {
/* this is a pci-pci bridge, do its devices next */
next = dev->subordinate->devices.next;
bus = dev->subordinate;
} else
next = dev->bus_list.next;
/* Run device routines with the device locked */
down(&dev->dev.sem);
cb(dev, userdata);
up(&dev->dev.sem);
}
up_read(&pci_bus_sem);
}
EXPORT_SYMBOL(pci_bus_alloc_resource);
EXPORT_SYMBOL_GPL(pci_bus_add_device);
EXPORT_SYMBOL(pci_bus_add_devices);
EXPORT_SYMBOL(pci_enable_bridges);