On Fri, Feb 17, 2017 at 03:20:23PM +0530, Kishon Vijay Abraham I wrote: > Introduce a new configfs entry to configure the EP function (like > configuring the standard configuration header entries) and to > bind the EP function with EP controller. > > Signed-off-by: Kishon Vijay Abraham I <kishon@xxxxxx> > --- > drivers/pci/endpoint/Kconfig | 14 +- > drivers/pci/endpoint/Makefile | 1 + > drivers/pci/endpoint/pci-ep-cfs.c | 427 +++++++++++++++++++++++++++++++++++++ > 3 files changed, 440 insertions(+), 2 deletions(-) > create mode 100644 drivers/pci/endpoint/pci-ep-cfs.c > > diff --git a/drivers/pci/endpoint/Kconfig b/drivers/pci/endpoint/Kconfig > index 7eb1c79..8470f0b 100644 > --- a/drivers/pci/endpoint/Kconfig > +++ b/drivers/pci/endpoint/Kconfig > @@ -6,7 +6,6 @@ menu "PCI Endpoint" > > config PCI_ENDPOINT > bool "PCI Endpoint Support" > - select CONFIGFS_FS > help > Enable this configuration option to support configurable PCI > endpoint. This should be enabled if the platform has a PCI > @@ -14,8 +13,19 @@ config PCI_ENDPOINT > > Enabling this option will build the endpoint library, which > includes endpoint controller library and endpoint function > - library. > + library. This will also enable the configfs entry required to > + configure the endpoint function and used to bind the > + function with a endpoint controller. > > If in doubt, say "N" to disable Endpoint support. > > +config PCI_ENDPOINT_CONFIGFS > + bool "PCI Endpoint Configfs Support" > + depends on PCI_ENDPOINT > + select CONFIGFS_FS > + help > + This will enable the configfs entry that can be used to > + configure the endpoint function and used to bind the > + function with a endpoint controller. > + > endmenu > diff --git a/drivers/pci/endpoint/Makefile b/drivers/pci/endpoint/Makefile > index dc1bc16..dd9163c 100644 > --- a/drivers/pci/endpoint/Makefile > +++ b/drivers/pci/endpoint/Makefile > @@ -4,3 +4,4 @@ > > obj-$(CONFIG_PCI_ENDPOINT) += pci-epc-core.o pci-epf-core.o\ > pci-epc-mem.o > +obj-$(CONFIG_PCI_ENDPOINT_CONFIGFS) += pci-ep-cfs.o > diff --git a/drivers/pci/endpoint/pci-ep-cfs.c b/drivers/pci/endpoint/pci-ep-cfs.c > new file mode 100644 > index 0000000..ed0f8c2 > --- /dev/null > +++ b/drivers/pci/endpoint/pci-ep-cfs.c > @@ -0,0 +1,427 @@ > +/** > + * configfs to configure the PCI endpoint > + * > + * Copyright (C) 2017 Texas Instruments > + * Author: Kishon Vijay Abraham I <kishon@xxxxxx> > + * > + * This program is free software: you can redistribute it and/or modify > + * it under the terms of the GNU General Public License version 2 of > + * the License as published by the Free Software Foundation. > + * > + * This program is distributed in the hope that it will be useful, > + * but WITHOUT ANY WARRANTY; without even the implied warranty of > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the > + * GNU General Public License for more details. > + * > + * You should have received a copy of the GNU General Public License > + * along with this program. If not, see <http://www.gnu.org/licenses/>. > + */ > + > +#include <linux/configfs.h> > +#include <linux/module.h> > +#include <linux/slab.h> > + > +#include <linux/pci-epc.h> > +#include <linux/pci-epf.h> > + > +struct pci_epf_info { > + struct config_group group; > + struct list_head list; > + struct pci_epf *epf; > +}; > + > +struct pci_ep_info { > + struct config_group group; > + struct config_group pci_epf_group; > + /* mutex to protect pci_epf list */ > + struct mutex lock; > + struct list_head pci_epf; > + const char *epc_name; > + struct pci_epc *epc; > +}; > + > +static inline struct pci_epf_info *to_pci_epf_info(struct config_item *item) > +{ > + return container_of(to_config_group(item), struct pci_epf_info, group); > +} > + > +static inline struct pci_ep_info *to_pci_ep_info(struct config_item *item) > +{ > + return container_of(to_config_group(item), struct pci_ep_info, group); > +} > + > +#define PCI_EPF_HEADER_R(_name) \ > +static ssize_t pci_epf_##_name##_show(struct config_item *item, char *page) \ > +{ \ > + struct pci_epf *epf = to_pci_epf_info(item)->epf; \ > + if (!epf->header) { \ > + WARN_ON_ONCE("epf device not bound to function driver\n"); \ WARN_ON_ONCE takes a string to evaluate as argument, not a message > + return 0; and if we return 0 here the callers will retry because that is interpreted as a short read. The code should be something like: if (WARN_ON_ONCE(!epf->header)) return -EINVAL; > + if (!epf->header) { \ > + WARN_ON_ONCE("epf device not bound to function driver\n"); \ > + return 0; \ > + } \ Same here, and a couple more instances down below.
