diff options
Diffstat (limited to 'drivers/pci/endpoint/pci-epf-core.c')
-rw-r--r-- | drivers/pci/endpoint/pci-epf-core.c | 359 |
1 files changed, 359 insertions, 0 deletions
diff --git a/drivers/pci/endpoint/pci-epf-core.c b/drivers/pci/endpoint/pci-epf-core.c new file mode 100644 index 0000000..6877d6a --- /dev/null +++ b/drivers/pci/endpoint/pci-epf-core.c @@ -0,0 +1,359 @@ +/** + * PCI Endpoint *Function* (EPF) library + * + * Copyright (C) 2017 Texas Instruments + * Author: Kishon Vijay Abraham I <kishon@ti.com> + * + * 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/device.h> +#include <linux/dma-mapping.h> +#include <linux/slab.h> +#include <linux/module.h> + +#include <linux/pci-epc.h> +#include <linux/pci-epf.h> +#include <linux/pci-ep-cfs.h> + +static struct bus_type pci_epf_bus_type; +static struct device_type pci_epf_type; + +/** + * pci_epf_linkup() - Notify the function driver that EPC device has + * established a connection with the Root Complex. + * @epf: the EPF device bound to the EPC device which has established + * the connection with the host + * + * Invoke to notify the function driver that EPC device has established + * a connection with the Root Complex. + */ +void pci_epf_linkup(struct pci_epf *epf) +{ + if (!epf->driver) { + dev_WARN(&epf->dev, "epf device not bound to driver\n"); + return; + } + + epf->driver->ops->linkup(epf); +} +EXPORT_SYMBOL_GPL(pci_epf_linkup); + +/** + * pci_epf_unbind() - Notify the function driver that the binding between the + * EPF device and EPC device has been lost + * @epf: the EPF device which has lost the binding with the EPC device + * + * Invoke to notify the function driver that the binding between the EPF device + * and EPC device has been lost. + */ +void pci_epf_unbind(struct pci_epf *epf) +{ + if (!epf->driver) { + dev_WARN(&epf->dev, "epf device not bound to driver\n"); + return; + } + + epf->driver->ops->unbind(epf); + module_put(epf->driver->owner); +} +EXPORT_SYMBOL_GPL(pci_epf_unbind); + +/** + * pci_epf_bind() - Notify the function driver that the EPF device has been + * bound to a EPC device + * @epf: the EPF device which has been bound to the EPC device + * + * Invoke to notify the function driver that it has been bound to a EPC device + */ +int pci_epf_bind(struct pci_epf *epf) +{ + if (!epf->driver) { + dev_WARN(&epf->dev, "epf device not bound to driver\n"); + return -EINVAL; + } + + if (!try_module_get(epf->driver->owner)) + return -EAGAIN; + + return epf->driver->ops->bind(epf); +} +EXPORT_SYMBOL_GPL(pci_epf_bind); + +/** + * pci_epf_free_space() - free the allocated PCI EPF register space + * @addr: the virtual address of the PCI EPF register space + * @bar: the BAR number corresponding to the register space + * + * Invoke to free the allocated PCI EPF register space. + */ +void pci_epf_free_space(struct pci_epf *epf, void *addr, enum pci_barno bar) +{ + struct device *dev = &epf->dev; + + if (!addr) + return; + + dma_free_coherent(dev, epf->bar[bar].size, addr, + epf->bar[bar].phys_addr); + + epf->bar[bar].phys_addr = 0; + epf->bar[bar].size = 0; +} +EXPORT_SYMBOL_GPL(pci_epf_free_space); + +/** + * pci_epf_alloc_space() - allocate memory for the PCI EPF register space + * @size: the size of the memory that has to be allocated + * @bar: the BAR number corresponding to the allocated register space + * + * Invoke to allocate memory for the PCI EPF register space. + */ +void *pci_epf_alloc_space(struct pci_epf *epf, size_t size, enum pci_barno bar) +{ + void *space; + struct device *dev = &epf->dev; + dma_addr_t phys_addr; + + if (size < 128) + size = 128; + size = roundup_pow_of_two(size); + + space = dma_alloc_coherent(dev, size, &phys_addr, GFP_KERNEL); + if (!space) { + dev_err(dev, "failed to allocate mem space\n"); + return NULL; + } + + epf->bar[bar].phys_addr = phys_addr; + epf->bar[bar].size = size; + + return space; +} +EXPORT_SYMBOL_GPL(pci_epf_alloc_space); + +/** + * pci_epf_unregister_driver() - unregister the PCI EPF driver + * @driver: the PCI EPF driver that has to be unregistered + * + * Invoke to unregister the PCI EPF driver. + */ +void pci_epf_unregister_driver(struct pci_epf_driver *driver) +{ + pci_ep_cfs_remove_epf_group(driver->group); + driver_unregister(&driver->driver); +} +EXPORT_SYMBOL_GPL(pci_epf_unregister_driver); + +/** + * __pci_epf_register_driver() - register a new PCI EPF driver + * @driver: structure representing PCI EPF driver + * @owner: the owner of the module that registers the PCI EPF driver + * + * Invoke to register a new PCI EPF driver. + */ +int __pci_epf_register_driver(struct pci_epf_driver *driver, + struct module *owner) +{ + int ret; + + if (!driver->ops) + return -EINVAL; + + if (!driver->ops->bind || !driver->ops->unbind || !driver->ops->linkup) + return -EINVAL; + + driver->driver.bus = &pci_epf_bus_type; + driver->driver.owner = owner; + + ret = driver_register(&driver->driver); + if (ret) + return ret; + + driver->group = pci_ep_cfs_add_epf_group(driver->driver.name); + + return 0; +} +EXPORT_SYMBOL_GPL(__pci_epf_register_driver); + +/** + * pci_epf_destroy() - destroy the created PCI EPF device + * @epf: the PCI EPF device that has to be destroyed. + * + * Invoke to destroy the PCI EPF device created by invoking pci_epf_create(). + */ +void pci_epf_destroy(struct pci_epf *epf) +{ + device_unregister(&epf->dev); +} +EXPORT_SYMBOL_GPL(pci_epf_destroy); + +/** + * pci_epf_create() - create a new PCI EPF device + * @name: the name of the PCI EPF device. This name will be used to bind the + * the EPF device to a EPF driver + * + * Invoke to create a new PCI EPF device by providing the name of the function + * device. + */ +struct pci_epf *pci_epf_create(const char *name) +{ + int ret; + struct pci_epf *epf; + struct device *dev; + char *func_name; + char *buf; + + epf = kzalloc(sizeof(*epf), GFP_KERNEL); + if (!epf) { + ret = -ENOMEM; + goto err_ret; + } + + buf = kstrdup(name, GFP_KERNEL); + if (!buf) { + ret = -ENOMEM; + goto free_epf; + } + + func_name = buf; + buf = strchrnul(buf, '.'); + *buf = '\0'; + + epf->name = kstrdup(func_name, GFP_KERNEL); + if (!epf->name) { + ret = -ENOMEM; + goto free_func_name; + } + + dev = &epf->dev; + device_initialize(dev); + dev->bus = &pci_epf_bus_type; + dev->type = &pci_epf_type; + + ret = dev_set_name(dev, "%s", name); + if (ret) + goto put_dev; + + ret = device_add(dev); + if (ret) + goto put_dev; + + kfree(func_name); + return epf; + +put_dev: + put_device(dev); + kfree(epf->name); + +free_func_name: + kfree(func_name); + +free_epf: + kfree(epf); + +err_ret: + return ERR_PTR(ret); +} +EXPORT_SYMBOL_GPL(pci_epf_create); + +static void pci_epf_dev_release(struct device *dev) +{ + struct pci_epf *epf = to_pci_epf(dev); + + kfree(epf->name); + kfree(epf); +} + +static struct device_type pci_epf_type = { + .release = pci_epf_dev_release, +}; + +static int +pci_epf_match_id(const struct pci_epf_device_id *id, const struct pci_epf *epf) +{ + while (id->name[0]) { + if (strcmp(epf->name, id->name) == 0) + return true; + id++; + } + + return false; +} + +static int pci_epf_device_match(struct device *dev, struct device_driver *drv) +{ + struct pci_epf *epf = to_pci_epf(dev); + struct pci_epf_driver *driver = to_pci_epf_driver(drv); + + if (driver->id_table) + return pci_epf_match_id(driver->id_table, epf); + + return !strcmp(epf->name, drv->name); +} + +static int pci_epf_device_probe(struct device *dev) +{ + struct pci_epf *epf = to_pci_epf(dev); + struct pci_epf_driver *driver = to_pci_epf_driver(dev->driver); + + if (!driver->probe) + return -ENODEV; + + epf->driver = driver; + + return driver->probe(epf); +} + +static int pci_epf_device_remove(struct device *dev) +{ + int ret; + struct pci_epf *epf = to_pci_epf(dev); + struct pci_epf_driver *driver = to_pci_epf_driver(dev->driver); + + ret = driver->remove(epf); + epf->driver = NULL; + + return ret; +} + +static struct bus_type pci_epf_bus_type = { + .name = "pci-epf", + .match = pci_epf_device_match, + .probe = pci_epf_device_probe, + .remove = pci_epf_device_remove, +}; + +static int __init pci_epf_init(void) +{ + int ret; + + ret = bus_register(&pci_epf_bus_type); + if (ret) { + pr_err("failed to register pci epf bus --> %d\n", ret); + return ret; + } + + return 0; +} +module_init(pci_epf_init); + +static void __exit pci_epf_exit(void) +{ + bus_unregister(&pci_epf_bus_type); +} +module_exit(pci_epf_exit); + +MODULE_DESCRIPTION("PCI EPF Library"); +MODULE_AUTHOR("Kishon Vijay Abraham I <kishon@ti.com>"); +MODULE_LICENSE("GPL v2"); |