Merge branch 'upstream-fixes' into upstream

[powerpc.git] / Documentation / pci.txt

diff --git a/Documentation/pci.txt b/Documentation/pci.txt
index 711210b..2b395e4 100644 (file)
--- a/Documentation/pci.txt
+++ b/Documentation/pci.txt
@@ -213,11 +213,19 @@ have been remapped by the kernel.
 
    See Documentation/IO-mapping.txt for how to access device memory.
 
 
    See Documentation/IO-mapping.txt for how to access device memory.
 

-   You still need to call request_region() for I/O regions and
-request_mem_region() for memory regions to make sure nobody else is using the
-same device.
-
-   All interrupt handlers should be registered with SA_SHIRQ and use the devid
+   The device driver needs to call pci_request_region() to make sure
+no other device is already using the same resource. The driver is expected
+to determine MMIO and IO Port resource availability _before_ calling
+pci_enable_device().  Conversely, drivers should call pci_release_region()
+_after_ calling pci_disable_device(). The idea is to prevent two devices
+colliding on the same address range.
+
+Generic flavors of pci_request_region() are request_mem_region()
+(for MMIO ranges) and request_region() (for IO Port ranges).
+Use these for address resources that are not described by "normal" PCI
+interfaces (e.g. BAR).
+
+   All interrupt handlers should be registered with IRQF_SHARED and use the devid

 to map IRQs to devices (remember that all PCI interrupts are shared).
 
 
 to map IRQs to devices (remember that all PCI interrupts are shared).
 
 


@@ -259,7 +267,17 @@ on the bus need to be capable of doing it, so this is something which needs
 to be handled by platform and generic code, not individual drivers.
 
 
 to be handled by platform and generic code, not individual drivers.
 
 

-8. Obsolete functions
+8. Vendor and device identifications
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+For the future, let's avoid adding device ids to include/linux/pci_ids.h.
+
+PCI_VENDOR_ID_xxx for vendors, and a hex constant for device ids.
+
+Rationale:  PCI_VENDOR_ID_xxx constants are re-used, but device ids are not.
+    Further, device ids are arbitrary hex numbers, normally used only in a
+    single location, the pci_device_id table.
+
+9. Obsolete functions

 ~~~~~~~~~~~~~~~~~~~~~
 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
 ~~~~~~~~~~~~~~~~~~~~~
 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