diff options
Diffstat (limited to 'Documentation')
| -rw-r--r-- | Documentation/pci.txt | 14 |
1 files changed, 11 insertions, 3 deletions
diff --git a/Documentation/pci.txt b/Documentation/pci.txt index 66bbbf1d1ef..3242e5c1ee9 100644 --- a/Documentation/pci.txt +++ b/Documentation/pci.txt @@ -213,9 +213,17 @@ have been remapped by the kernel. 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. + 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 SA_SHIRQ and use the devid to map IRQs to devices (remember that all PCI interrupts are shared). |