[PATCH 2/2] PCI: endpoint: Add kdoc description of pci_epf_type_add_cfs()

[Damien Le Moal <dlemoal@kernel.org>]

Restore an improve the kdoc function description for
pci_epf_type_add_cfs() that was removed with commit
893f14fed7d3 ("PCI: endpoint: Move pci_epf_type_add_cfs() code").

Fixes: 893f14fed7d3 ("PCI: endpoint: Move pci_epf_type_add_cfs() code")
Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
---
 drivers/pci/endpoint/pci-ep-cfs.c | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

diff --git a/drivers/pci/endpoint/pci-ep-cfs.c b/drivers/pci/endpoint/pci-ep-cfs.c
index d8a6abe2c31c..15e17a661875 100644
--- a/drivers/pci/endpoint/pci-ep-cfs.c
+++ b/drivers/pci/endpoint/pci-ep-cfs.c
@@ -509,6 +509,24 @@ static const struct config_item_type pci_epf_type = {
 	.ct_owner	= THIS_MODULE,
 };
 
+/**
+ * pci_epf_type_add_cfs() - Help function drivers to expose function specific   
+ *                          attributes in configfs
+ * @epf: the EPF device that has to be configured using configfs
+ * @group: the parent configfs group (corresponding to entries in
+ *         pci_epf_device_id)
+ *
+ * Invoke to expose function specific attributes in configfs.
+ *
+ * Return: NULL if the function driver
+ *
+ * Return: A pointer to a config_group structure or NULL if the function driver
+ * does not have anything to expose (attributes configured by user) or if the
+ * the function driver does not implement the add_cfs() method.
+ *
+ * Returns an error pointer if this function is called for an unbound EPF device
+ * or if the EPF driver add_cfs() method fails.
+ */
 static struct config_group *pci_epf_type_add_cfs(struct pci_epf *epf,
 						 struct config_group *group)
 {
-- 
2.40.1