1 // SPDX-License-Identifier: GPL-2.0
3 * PCI Endpoint *Function* (EPF) library
5 * Copyright (C) 2017 Texas Instruments
6 * Author: Kishon Vijay Abraham I <kishon@ti.com>
9 #include <linux/device.h>
10 #include <linux/dma-mapping.h>
11 #include <linux/slab.h>
12 #include <linux/module.h>
14 #include <linux/pci-epc.h>
15 #include <linux/pci-epf.h>
16 #include <linux/pci-ep-cfs.h>
18 static DEFINE_MUTEX(pci_epf_mutex);
20 static struct bus_type pci_epf_bus_type;
21 static const struct device_type pci_epf_type;
24 * pci_epf_linkup() - Notify the function driver that EPC device has
25 * established a connection with the Root Complex.
26 * @epf: the EPF device bound to the EPC device which has established
27 * the connection with the host
29 * Invoke to notify the function driver that EPC device has established
30 * a connection with the Root Complex.
32 void pci_epf_linkup(struct pci_epf *epf)
35 dev_WARN(&epf->dev, "epf device not bound to driver\n");
39 epf->driver->ops->linkup(epf);
41 EXPORT_SYMBOL_GPL(pci_epf_linkup);
44 * pci_epf_unbind() - Notify the function driver that the binding between the
45 * EPF device and EPC device has been lost
46 * @epf: the EPF device which has lost the binding with the EPC device
48 * Invoke to notify the function driver that the binding between the EPF device
49 * and EPC device has been lost.
51 void pci_epf_unbind(struct pci_epf *epf)
54 dev_WARN(&epf->dev, "epf device not bound to driver\n");
58 epf->driver->ops->unbind(epf);
59 module_put(epf->driver->owner);
61 EXPORT_SYMBOL_GPL(pci_epf_unbind);
64 * pci_epf_bind() - Notify the function driver that the EPF device has been
65 * bound to a EPC device
66 * @epf: the EPF device which has been bound to the EPC device
68 * Invoke to notify the function driver that it has been bound to a EPC device
70 int pci_epf_bind(struct pci_epf *epf)
73 dev_WARN(&epf->dev, "epf device not bound to driver\n");
77 if (!try_module_get(epf->driver->owner))
80 return epf->driver->ops->bind(epf);
82 EXPORT_SYMBOL_GPL(pci_epf_bind);
85 * pci_epf_free_space() - free the allocated PCI EPF register space
86 * @addr: the virtual address of the PCI EPF register space
87 * @bar: the BAR number corresponding to the register space
89 * Invoke to free the allocated PCI EPF register space.
91 void pci_epf_free_space(struct pci_epf *epf, void *addr, enum pci_barno bar)
93 struct device *dev = epf->epc->dev.parent;
98 dma_free_coherent(dev, epf->bar[bar].size, addr,
99 epf->bar[bar].phys_addr);
101 epf->bar[bar].phys_addr = 0;
102 epf->bar[bar].size = 0;
103 epf->bar[bar].barno = 0;
104 epf->bar[bar].flags = 0;
106 EXPORT_SYMBOL_GPL(pci_epf_free_space);
109 * pci_epf_alloc_space() - allocate memory for the PCI EPF register space
110 * @size: the size of the memory that has to be allocated
111 * @bar: the BAR number corresponding to the allocated register space
112 * @align: alignment size for the allocation region
114 * Invoke to allocate memory for the PCI EPF register space.
116 void *pci_epf_alloc_space(struct pci_epf *epf, size_t size, enum pci_barno bar,
120 struct device *dev = epf->epc->dev.parent;
121 dma_addr_t phys_addr;
127 size = ALIGN(size, align);
129 size = roundup_pow_of_two(size);
131 space = dma_alloc_coherent(dev, size, &phys_addr, GFP_KERNEL);
133 dev_err(dev, "failed to allocate mem space\n");
137 epf->bar[bar].phys_addr = phys_addr;
138 epf->bar[bar].size = size;
139 epf->bar[bar].barno = bar;
140 epf->bar[bar].flags |= upper_32_bits(size) ?
141 PCI_BASE_ADDRESS_MEM_TYPE_64 :
142 PCI_BASE_ADDRESS_MEM_TYPE_32;
146 EXPORT_SYMBOL_GPL(pci_epf_alloc_space);
148 static void pci_epf_remove_cfs(struct pci_epf_driver *driver)
150 struct config_group *group, *tmp;
152 if (!IS_ENABLED(CONFIG_PCI_ENDPOINT_CONFIGFS))
155 mutex_lock(&pci_epf_mutex);
156 list_for_each_entry_safe(group, tmp, &driver->epf_group, group_entry)
157 pci_ep_cfs_remove_epf_group(group);
158 list_del(&driver->epf_group);
159 mutex_unlock(&pci_epf_mutex);
163 * pci_epf_unregister_driver() - unregister the PCI EPF driver
164 * @driver: the PCI EPF driver that has to be unregistered
166 * Invoke to unregister the PCI EPF driver.
168 void pci_epf_unregister_driver(struct pci_epf_driver *driver)
170 pci_epf_remove_cfs(driver);
171 driver_unregister(&driver->driver);
173 EXPORT_SYMBOL_GPL(pci_epf_unregister_driver);
175 static int pci_epf_add_cfs(struct pci_epf_driver *driver)
177 struct config_group *group;
178 const struct pci_epf_device_id *id;
180 if (!IS_ENABLED(CONFIG_PCI_ENDPOINT_CONFIGFS))
183 INIT_LIST_HEAD(&driver->epf_group);
185 id = driver->id_table;
186 while (id->name[0]) {
187 group = pci_ep_cfs_add_epf_group(id->name);
189 pci_epf_remove_cfs(driver);
190 return PTR_ERR(group);
193 mutex_lock(&pci_epf_mutex);
194 list_add_tail(&group->group_entry, &driver->epf_group);
195 mutex_unlock(&pci_epf_mutex);
203 * __pci_epf_register_driver() - register a new PCI EPF driver
204 * @driver: structure representing PCI EPF driver
205 * @owner: the owner of the module that registers the PCI EPF driver
207 * Invoke to register a new PCI EPF driver.
209 int __pci_epf_register_driver(struct pci_epf_driver *driver,
210 struct module *owner)
217 if (!driver->ops->bind || !driver->ops->unbind || !driver->ops->linkup)
220 driver->driver.bus = &pci_epf_bus_type;
221 driver->driver.owner = owner;
223 ret = driver_register(&driver->driver);
227 pci_epf_add_cfs(driver);
231 EXPORT_SYMBOL_GPL(__pci_epf_register_driver);
234 * pci_epf_destroy() - destroy the created PCI EPF device
235 * @epf: the PCI EPF device that has to be destroyed.
237 * Invoke to destroy the PCI EPF device created by invoking pci_epf_create().
239 void pci_epf_destroy(struct pci_epf *epf)
241 device_unregister(&epf->dev);
243 EXPORT_SYMBOL_GPL(pci_epf_destroy);
246 * pci_epf_create() - create a new PCI EPF device
247 * @name: the name of the PCI EPF device. This name will be used to bind the
248 * the EPF device to a EPF driver
250 * Invoke to create a new PCI EPF device by providing the name of the function
253 struct pci_epf *pci_epf_create(const char *name)
260 epf = kzalloc(sizeof(*epf), GFP_KERNEL);
262 return ERR_PTR(-ENOMEM);
264 len = strchrnul(name, '.') - name;
265 epf->name = kstrndup(name, len, GFP_KERNEL);
268 return ERR_PTR(-ENOMEM);
272 device_initialize(dev);
273 dev->bus = &pci_epf_bus_type;
274 dev->type = &pci_epf_type;
276 ret = dev_set_name(dev, "%s", name);
282 ret = device_add(dev);
290 EXPORT_SYMBOL_GPL(pci_epf_create);
292 const struct pci_epf_device_id *
293 pci_epf_match_device(const struct pci_epf_device_id *id, struct pci_epf *epf)
299 if (strcmp(epf->name, id->name) == 0)
306 EXPORT_SYMBOL_GPL(pci_epf_match_device);
308 static void pci_epf_dev_release(struct device *dev)
310 struct pci_epf *epf = to_pci_epf(dev);
316 static const struct device_type pci_epf_type = {
317 .release = pci_epf_dev_release,
321 pci_epf_match_id(const struct pci_epf_device_id *id, const struct pci_epf *epf)
323 while (id->name[0]) {
324 if (strcmp(epf->name, id->name) == 0)
332 static int pci_epf_device_match(struct device *dev, struct device_driver *drv)
334 struct pci_epf *epf = to_pci_epf(dev);
335 struct pci_epf_driver *driver = to_pci_epf_driver(drv);
337 if (driver->id_table)
338 return pci_epf_match_id(driver->id_table, epf);
340 return !strcmp(epf->name, drv->name);
343 static int pci_epf_device_probe(struct device *dev)
345 struct pci_epf *epf = to_pci_epf(dev);
346 struct pci_epf_driver *driver = to_pci_epf_driver(dev->driver);
351 epf->driver = driver;
353 return driver->probe(epf);
356 static int pci_epf_device_remove(struct device *dev)
359 struct pci_epf *epf = to_pci_epf(dev);
360 struct pci_epf_driver *driver = to_pci_epf_driver(dev->driver);
363 ret = driver->remove(epf);
369 static struct bus_type pci_epf_bus_type = {
371 .match = pci_epf_device_match,
372 .probe = pci_epf_device_probe,
373 .remove = pci_epf_device_remove,
376 static int __init pci_epf_init(void)
380 ret = bus_register(&pci_epf_bus_type);
382 pr_err("failed to register pci epf bus --> %d\n", ret);
388 module_init(pci_epf_init);
390 static void __exit pci_epf_exit(void)
392 bus_unregister(&pci_epf_bus_type);
394 module_exit(pci_epf_exit);
396 MODULE_DESCRIPTION("PCI EPF Library");
397 MODULE_AUTHOR("Kishon Vijay Abraham I <kishon@ti.com>");
398 MODULE_LICENSE("GPL v2");