PCI: dwc: ep: Add Kernel-doc comments for APIs

All of the APIs are missing the Kernel-doc comments. Hence, add them.

Link: https://lore.kernel.org/linux-pci/20240327-pci-dbi-rework-v12-2-082625472414@linaro.org
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Krzysztof Wilczyński <kwilczynski@kernel.org>
Reviewed-by: Frank Li <Frank.Li@nxp.com>
Reviewed-by: Niklas Cassel <cassel@kernel.org>

Author: Mani-Sadhasivam

drivers/pci/controller/dwc/pcie-designware-ep.c

@@ -15,6 +15,10 @@
 #include <linux/pci-epc.h>
 #include <linux/pci-epf.h>
 
+/**
+ * dw_pcie_ep_linkup - Notify EPF drivers about Link Up event
+ * @ep: DWC EP device
+ */
 void dw_pcie_ep_linkup(struct dw_pcie_ep *ep)
 {
 	struct pci_epc *epc = ep->epc;
@@ -23,6 +27,10 @@ void dw_pcie_ep_linkup(struct dw_pcie_ep *ep)
 }
 EXPORT_SYMBOL_GPL(dw_pcie_ep_linkup);
 
+/**
+ * dw_pcie_ep_init_notify - Notify EPF drivers about EPC initialization complete
+ * @ep: DWC EP device
+ */
 void dw_pcie_ep_init_notify(struct dw_pcie_ep *ep)
 {
 	struct pci_epc *epc = ep->epc;
@@ -31,6 +39,14 @@ void dw_pcie_ep_init_notify(struct dw_pcie_ep *ep)
 }
 EXPORT_SYMBOL_GPL(dw_pcie_ep_init_notify);
 
+/**
+ * dw_pcie_ep_get_func_from_ep - Get the struct dw_pcie_ep_func corresponding to
+ *				 the endpoint function
+ * @ep: DWC EP device
+ * @func_no: Function number of the endpoint device
+ *
+ * Return: struct dw_pcie_ep_func if success, NULL otherwise.
+ */
 struct dw_pcie_ep_func *
 dw_pcie_ep_get_func_from_ep(struct dw_pcie_ep *ep, u8 func_no)
 {
@@ -61,6 +77,11 @@ static void __dw_pcie_ep_reset_bar(struct dw_pcie *pci, u8 func_no,
 	dw_pcie_dbi_ro_wr_dis(pci);
 }
 
+/**
+ * dw_pcie_ep_reset_bar - Reset endpoint BAR
+ * @pci: DWC PCI device
+ * @bar: BAR number of the endpoint
+ */
 void dw_pcie_ep_reset_bar(struct dw_pcie *pci, enum pci_barno bar)
 {
 	u8 func_no, funcs;
@@ -440,6 +461,13 @@ static const struct pci_epc_ops epc_ops = {
 	.get_features		= dw_pcie_ep_get_features,
 };
 
+/**
+ * dw_pcie_ep_raise_intx_irq - Raise INTx IRQ to the host
+ * @ep: DWC EP device
+ * @func_no: Function number of the endpoint
+ *
+ * Return: 0 if success, errono otherwise.
+ */
 int dw_pcie_ep_raise_intx_irq(struct dw_pcie_ep *ep, u8 func_no)
 {
 	struct dw_pcie *pci = to_dw_pcie_from_ep(ep);
@@ -451,6 +479,14 @@ int dw_pcie_ep_raise_intx_irq(struct dw_pcie_ep *ep, u8 func_no)
 }
 EXPORT_SYMBOL_GPL(dw_pcie_ep_raise_intx_irq);
 
+/**
+ * dw_pcie_ep_raise_msi_irq - Raise MSI IRQ to the host
+ * @ep: DWC EP device
+ * @func_no: Function number of the endpoint
+ * @interrupt_num: Interrupt number to be raised
+ *
+ * Return: 0 if success, errono otherwise.
+ */
 int dw_pcie_ep_raise_msi_irq(struct dw_pcie_ep *ep, u8 func_no,
 			     u8 interrupt_num)
 {
@@ -500,6 +536,15 @@ int dw_pcie_ep_raise_msi_irq(struct dw_pcie_ep *ep, u8 func_no,
 }
 EXPORT_SYMBOL_GPL(dw_pcie_ep_raise_msi_irq);
 
+/**
+ * dw_pcie_ep_raise_msix_irq_doorbell - Raise MSI-X to the host using Doorbell
+ *					method
+ * @ep: DWC EP device
+ * @func_no: Function number of the endpoint device
+ * @interrupt_num: Interrupt number to be raised
+ *
+ * Return: 0 if success, errno otherwise.
+ */
 int dw_pcie_ep_raise_msix_irq_doorbell(struct dw_pcie_ep *ep, u8 func_no,
 				       u16 interrupt_num)
 {
@@ -519,6 +564,14 @@ int dw_pcie_ep_raise_msix_irq_doorbell(struct dw_pcie_ep *ep, u8 func_no,
 	return 0;
 }
 
+/**
+ * dw_pcie_ep_raise_msix_irq - Raise MSI-X to the host
+ * @ep: DWC EP device
+ * @func_no: Function number of the endpoint device
+ * @interrupt_num: Interrupt number to be raised
+ *
+ * Return: 0 if success, errno otherwise.
+ */
 int dw_pcie_ep_raise_msix_irq(struct dw_pcie_ep *ep, u8 func_no,
 			      u16 interrupt_num)
 {
@@ -566,6 +619,13 @@ int dw_pcie_ep_raise_msix_irq(struct dw_pcie_ep *ep, u8 func_no,
 	return 0;
 }
 
+/**
+ * dw_pcie_ep_exit - Deinitialize the endpoint device
+ * @ep: DWC EP device
+ *
+ * Deinitialize the endpoint device. EPC device is not destroyed since that will
+ * be taken care by Devres.
+ */
 void dw_pcie_ep_exit(struct dw_pcie_ep *ep)
 {
 	struct dw_pcie *pci = to_dw_pcie_from_ep(ep);
@@ -601,6 +661,14 @@ static unsigned int dw_pcie_ep_find_ext_capability(struct dw_pcie *pci, int cap)
 	return 0;
 }
 
+/**
+ * dw_pcie_ep_init_complete - Complete DWC EP initialization
+ * @ep: DWC EP device
+ *
+ * Complete the initialization of the registers (CSRs) specific to DWC EP. This
+ * API should be called only when the endpoint receives an active refclk (either
+ * from host or generated locally).
+ */
 int dw_pcie_ep_init_complete(struct dw_pcie_ep *ep)
 {
 	struct dw_pcie *pci = to_dw_pcie_from_ep(ep);
@@ -723,6 +791,15 @@ int dw_pcie_ep_init_complete(struct dw_pcie_ep *ep)
 }
 EXPORT_SYMBOL_GPL(dw_pcie_ep_init_complete);
 
+/**
+ * dw_pcie_ep_init - Initialize the endpoint device
+ * @ep: DWC EP device
+ *
+ * Initialize the endpoint device. Allocate resources and create the EPC
+ * device with the endpoint framework.
+ *
+ * Return: 0 if success, errno otherwise.
+ */
 int dw_pcie_ep_init(struct dw_pcie_ep *ep)
 {
 	int ret;