[PATCH 1/7] Documentation: PCI: endpoint/pci-endpoint-cfs: Guide to use SR-IOV

[Kishon Vijay Abraham I]

Add Documentation to help users use PCI endpoint to create virtual
functions using configfs. An endpoint function is designated as a
virtual endpoint function device when it is linked to a physical
endpoint function device (instead of a endpoint controller).

Signed-off-by: Kishon Vijay Abraham I <kishon@xxxxxx>
---
 Documentation/PCI/endpoint/pci-endpoint-cfs.rst | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/Documentation/PCI/endpoint/pci-endpoint-cfs.rst b/Documentation/PCI/endpoint/pci-endpoint-cfs.rst
index b6d39cdec56e..0f55c5511c6c 100644
--- a/Documentation/PCI/endpoint/pci-endpoint-cfs.rst
+++ b/Documentation/PCI/endpoint/pci-endpoint-cfs.rst
@@ -43,6 +43,7 @@ entries corresponding to EPF driver will be created by the EPF core.
 		.. <EPF Driver1>/
 			... <EPF Device 11>/
 			... <EPF Device 21>/
+			... <EPF Device 31>/
 		.. <EPF Driver2>/
 			... <EPF Device 12>/
 			... <EPF Device 22>/
@@ -68,6 +69,14 @@ created)
 				... subsys_vendor_id
 				... subsys_id
 				... interrupt_pin
+			        ... <Symlink EPF Device 31>/
+
+The <EPF Device> directory can have a list of symbolic links to
+other <EPF Device>. These symbolic links should be created by the user
+to represent the virtual functions that are bound to the physical
+function. In the above directory structure <EPF Device 11> is a physical
+function and <EPF Device 31> is a virtual function. A EPF device once it's
+linked to another EPF device, cannot be linked to a EPC device.
 
 EPC Device
 ==========
@@ -88,7 +97,8 @@ entries corresponding to EPC device will be created by the EPC core.
 
 The <EPC Device> directory will have a list of symbolic links to
 <EPF Device>. These symbolic links should be created by the user to
-represent the functions present in the endpoint device.
+represent the functions present in the endpoint device. Only <EPF Device>
+that represents a physical function can be linked to a EPC device.
 
 The <EPC Device> directory will also have a *start* field. Once
 "1" is written to this field, the endpoint device will be ready to
-- 
2.17.1