[PATCH] PCI documentation
Update the PCI Documentation to reflect some of the functions which have
recently been added and removed.
Index: Documentation/pci.txt
===================================================================
RCS file: /var/cvs/linux-2.5/Documentation/pci.txt,v
retrieving revision 1.4
Documentation/pci.txt | 37 ++++++++++++++++++++++---------------
1 files changed, 22 insertions(+), 15 deletions(-)
diff -Nru a/Documentation/pci.txt b/Documentation/pci.txt
--- a/Documentation/pci.txt Wed Jun 25 17:38:17 2003
+++ b/Documentation/pci.txt Wed Jun 25 17:38:17 2003
@@ -155,17 +155,11 @@
VENDOR_ID or DEVICE_ID. This allows searching for any device from a
specific vendor, for example.
- In case you need to decide according to some more complex criteria,
-you can walk the list of all known PCI devices yourself:
-
- struct pci_dev *dev;
- pci_for_each_dev(dev) {
- ... do anything you want with dev ...
- }
-
-For compatibility with device ordering in older kernels, you can also
-use pci_for_each_dev_reverse(dev) for walking the list in the opposite
-direction.
+Note that these functions are not hotplug-safe. Their hotplug-safe
+replacements are pci_get_device(), pci_get_class() and pci_get_subsys().
+They increment the reference count on the pci_dev that they return.
+You must eventually (possibly at module unload) decrement the reference
+count on these devices by calling pci_dev_put().
3. Enabling devices
@@ -193,6 +187,10 @@
string by pcibios_strerror. Most drivers expect that accesses to valid PCI
devices don't fail.
+ If you don't have a struct pci_dev available, you can call
+pci_bus_(read|write)_config_(byte|word|dword) to access a given device
+and function on that bus.
+
If you access fields in the standard portion of the config header, please
use symbolic names of locations and bits declared in <linux/pci.h>.
@@ -253,14 +251,23 @@
8. Obsolete functions
~~~~~~~~~~~~~~~~~~~~~
-There are several functions kept only for compatibility with old drivers
-not updated to the new PCI interface. Please don't use them in new code.
+There are several functions which you might come across when trying to
+port an old driver to the new PCI interface. They are no longer present
+in the kernel as they aren't compatible with hotplug or PCI domains or
+having sane locking.
-pcibios_present() Since ages, you don't need to test presence
- of PCI subsystem when trying to talk with it.
+pcibios_present() and Since ages, you don't need to test presence
+pci_present() of PCI subsystem when trying to talk to it.
If it's not there, the list of PCI devices
is empty and all functions for searching for
devices just return NULL.
pcibios_(read|write)_* Superseded by their pci_(read|write)_*
counterparts.
pcibios_find_* Superseded by their pci_find_* counterparts.
+pci_for_each_dev() Superseded by pci_find_device()
+pci_for_each_dev_reverse() Superseded by pci_find_device_reverse()
+pci_for_each_bus() Superseded by pci_find_next_bus()
+pci_find_device() Superseded by pci_get_device()
+pci_find_subsys() Superseded by pci_get_subsys()
+pcibios_find_class() Superseded by pci_find_class()
+pci_(read|write)_*_nodev() Superseded by pci_bus_(read|write)_*()
-
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