[PATCH v3 09/17] PCI: endpoint: Add pci_epf_ops for epf drivers to expose function specific attrs
From: Kishon Vijay Abraham I <hidden>
Date: 2020-09-04 07:53:32
Also in:
linux-pci, lkml
Subsystem:
pci endpoint subsystem, pci subsystem, the rest · Maintainers:
Manivannan Sadhasivam, Krzysztof Wilczyński, Bjorn Helgaas, Linus Torvalds
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. Signed-off-by: Kishon Vijay Abraham I <redacted> --- drivers/pci/endpoint/pci-epf-core.c | 32 +++++++++++++++++++++++++++++ include/linux/pci-epf.h | 5 +++++ 2 files changed, 37 insertions(+)
diff --git a/drivers/pci/endpoint/pci-epf-core.c b/drivers/pci/endpoint/pci-epf-core.c
index 79329ec6373c..7646c8660d42 100644
--- a/drivers/pci/endpoint/pci-epf-core.c
+++ b/drivers/pci/endpoint/pci-epf-core.c@@ -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
diff --git a/include/linux/pci-epf.h b/include/linux/pci-epf.h
index 1dc66824f5a8..b241e7dd171f 100644
--- a/include/linux/pci-epf.h
+++ b/include/linux/pci-epf.h@@ -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 */
--
2.17.1