Commit 256ae475 authored by Kishon Vijay Abraham I's avatar Kishon Vijay Abraham I Committed by Bjorn Helgaas
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PCI: endpoint: Add pci_epf_ops to expose function-specific attrs 

In addition to the attributes that are generic across function drivers
documented in Documentation/PCI/endpoint/pci-endpoint-cfs.rst, there could
be function-specific attributes that has to be exposed by the function
driver to be configured by the user. Add ->add_cfs() in pci_epf_ops to be
populated by the function driver if it has to expose any function-specific
attributes and pci_epf_type_add_cfs() to be invoked by pci-ep-cfs.c when
sub-directory to main function directory is created.

Link: https://lore.kernel.org/r/20210201195809.7342-10-kishon@ti.com


Signed-off-by: default avatarKishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: default avatarLorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: default avatarBjorn Helgaas <bhelgaas@google.com>
parent 87d5972e

drivers/pci/endpoint/pci-epf-core.c

+32 −0
Original line number Diff line number Diff line
@@ -20,6 +20,38 @@ static DEFINE_MUTEX(pci_epf_mutex); 
static struct bus_type pci_epf_bus_type;

static const struct device_type pci_epf_type;



/**

 * 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. If the function

 * driver does not have anything to expose (attributes configured by user),

 * return NULL.

 */

struct config_group *pci_epf_type_add_cfs(struct pci_epf *epf,

					  struct config_group *group)

{

	struct config_group *epf_type_group;



	if (!epf->driver) {

		dev_err(&epf->dev, "epf device not bound to driver\n");

		return NULL;

	}



	if (!epf->driver->ops->add_cfs)

		return NULL;



	mutex_lock(&epf->lock);

	epf_type_group = epf->driver->ops->add_cfs(epf, group);

	mutex_unlock(&epf->lock);



	return epf_type_group;

}

EXPORT_SYMBOL_GPL(pci_epf_type_add_cfs);



/**

 * pci_epf_unbind() - Notify the function driver that the binding between the

 *		      EPF device and EPC device has been lost

include/linux/pci-epf.h

+5 −0
Original line number Diff line number Diff line
@@ -62,10 +62,13 @@ struct pci_epf_header { 
 * @bind: ops to perform when a EPC device has been bound to EPF device

 * @unbind: ops to perform when a binding has been lost between a EPC device

 *	    and EPF device

 * @add_cfs: ops to initialize function specific configfs attributes

 */

struct pci_epf_ops {

	int	(*bind)(struct pci_epf *epf);

	void	(*unbind)(struct pci_epf *epf);

	struct config_group *(*add_cfs)(struct pci_epf *epf,

					struct config_group *group);

};



/**
@@ -188,4 +191,6 @@ void pci_epf_free_space(struct pci_epf *epf, void *addr, enum pci_barno bar, 
			enum pci_epc_interface_type type);

int pci_epf_bind(struct pci_epf *epf);

void pci_epf_unbind(struct pci_epf *epf);

struct config_group *pci_epf_type_add_cfs(struct pci_epf *epf,

					  struct config_group *group);

#endif /* __LINUX_PCI_EPF_H */