1 // SPDX-License-Identifier: GPL-2.0-only
5 * Copyright (C) 2013 MEN Mikroelektronik GmbH (www.men.de)
6 * Author: Johannes Thumshirn <johannes.thumshirn@men.de>
8 #include <linux/kernel.h>
9 #include <linux/module.h>
10 #include <linux/slab.h>
11 #include <linux/types.h>
12 #include <linux/idr.h>
13 #include <linux/mcb.h>
15 static DEFINE_IDA(mcb_ida);
17 static const struct mcb_device_id *mcb_match_id(const struct mcb_device_id *ids,
18 struct mcb_device *dev)
22 if (ids->device == dev->id)
31 static int mcb_match(struct device *dev, struct device_driver *drv)
33 struct mcb_driver *mdrv = to_mcb_driver(drv);
34 struct mcb_device *mdev = to_mcb_device(dev);
35 const struct mcb_device_id *found_id;
37 found_id = mcb_match_id(mdrv->id_table, mdev);
44 static int mcb_uevent(struct device *dev, struct kobj_uevent_env *env)
46 struct mcb_device *mdev = to_mcb_device(dev);
49 ret = add_uevent_var(env, "MODALIAS=mcb:16z%03d", mdev->id);
56 static int mcb_probe(struct device *dev)
58 struct mcb_driver *mdrv = to_mcb_driver(dev->driver);
59 struct mcb_device *mdev = to_mcb_device(dev);
60 const struct mcb_device_id *found_id;
61 struct module *carrier_mod;
64 found_id = mcb_match_id(mdrv->id_table, mdev);
68 carrier_mod = mdev->dev.parent->driver->owner;
69 if (!try_module_get(carrier_mod))
73 ret = mdrv->probe(mdev, found_id);
75 module_put(carrier_mod);
82 static int mcb_remove(struct device *dev)
84 struct mcb_driver *mdrv = to_mcb_driver(dev->driver);
85 struct mcb_device *mdev = to_mcb_device(dev);
86 struct module *carrier_mod;
90 carrier_mod = mdev->dev.parent->driver->owner;
91 module_put(carrier_mod);
93 put_device(&mdev->dev);
98 static void mcb_shutdown(struct device *dev)
100 struct mcb_driver *mdrv = to_mcb_driver(dev->driver);
101 struct mcb_device *mdev = to_mcb_device(dev);
103 if (mdrv && mdrv->shutdown)
104 mdrv->shutdown(mdev);
107 static ssize_t revision_show(struct device *dev, struct device_attribute *attr,
110 struct mcb_bus *bus = to_mcb_bus(dev);
112 return scnprintf(buf, PAGE_SIZE, "%d\n", bus->revision);
114 static DEVICE_ATTR_RO(revision);
116 static ssize_t model_show(struct device *dev, struct device_attribute *attr,
119 struct mcb_bus *bus = to_mcb_bus(dev);
121 return scnprintf(buf, PAGE_SIZE, "%c\n", bus->model);
123 static DEVICE_ATTR_RO(model);
125 static ssize_t minor_show(struct device *dev, struct device_attribute *attr,
128 struct mcb_bus *bus = to_mcb_bus(dev);
130 return scnprintf(buf, PAGE_SIZE, "%d\n", bus->minor);
132 static DEVICE_ATTR_RO(minor);
134 static ssize_t name_show(struct device *dev, struct device_attribute *attr,
137 struct mcb_bus *bus = to_mcb_bus(dev);
139 return scnprintf(buf, PAGE_SIZE, "%s\n", bus->name);
141 static DEVICE_ATTR_RO(name);
143 static struct attribute *mcb_bus_attrs[] = {
144 &dev_attr_revision.attr,
145 &dev_attr_model.attr,
146 &dev_attr_minor.attr,
151 static const struct attribute_group mcb_carrier_group = {
152 .attrs = mcb_bus_attrs,
155 static const struct attribute_group *mcb_carrier_groups[] = {
161 static struct bus_type mcb_bus_type = {
164 .uevent = mcb_uevent,
166 .remove = mcb_remove,
167 .shutdown = mcb_shutdown,
170 static struct device_type mcb_carrier_device_type = {
171 .name = "mcb-carrier",
172 .groups = mcb_carrier_groups,
176 * __mcb_register_driver() - Register a @mcb_driver at the system
177 * @drv: The @mcb_driver
178 * @owner: The @mcb_driver's module
179 * @mod_name: The name of the @mcb_driver's module
181 * Register a @mcb_driver at the system. Perform some sanity checks, if
182 * the .probe and .remove methods are provided by the driver.
184 int __mcb_register_driver(struct mcb_driver *drv, struct module *owner,
185 const char *mod_name)
187 if (!drv->probe || !drv->remove)
190 drv->driver.owner = owner;
191 drv->driver.bus = &mcb_bus_type;
192 drv->driver.mod_name = mod_name;
194 return driver_register(&drv->driver);
196 EXPORT_SYMBOL_NS_GPL(__mcb_register_driver, MCB);
199 * mcb_unregister_driver() - Unregister a @mcb_driver from the system
200 * @drv: The @mcb_driver
202 * Unregister a @mcb_driver from the system.
204 void mcb_unregister_driver(struct mcb_driver *drv)
206 driver_unregister(&drv->driver);
208 EXPORT_SYMBOL_NS_GPL(mcb_unregister_driver, MCB);
210 static void mcb_release_dev(struct device *dev)
212 struct mcb_device *mdev = to_mcb_device(dev);
214 mcb_bus_put(mdev->bus);
219 * mcb_device_register() - Register a mcb_device
220 * @bus: The @mcb_bus of the device
221 * @dev: The @mcb_device
223 * Register a specific @mcb_device at a @mcb_bus and the system itself.
225 int mcb_device_register(struct mcb_bus *bus, struct mcb_device *dev)
230 device_initialize(&dev->dev);
232 dev->dev.bus = &mcb_bus_type;
233 dev->dev.parent = bus->dev.parent;
234 dev->dev.release = mcb_release_dev;
235 dev->dma_dev = bus->carrier;
238 dev_set_name(&dev->dev, "mcb%d-16z%03d-%d:%d:%d",
239 bus->bus_nr, device_id, dev->inst, dev->group, dev->var);
241 ret = device_add(&dev->dev);
243 pr_err("Failed registering device 16z%03d on bus mcb%d (%d)\n",
244 device_id, bus->bus_nr, ret);
251 put_device(&dev->dev);
255 EXPORT_SYMBOL_NS_GPL(mcb_device_register, MCB);
257 static void mcb_free_bus(struct device *dev)
259 struct mcb_bus *bus = to_mcb_bus(dev);
261 put_device(bus->carrier);
262 ida_simple_remove(&mcb_ida, bus->bus_nr);
267 * mcb_alloc_bus() - Allocate a new @mcb_bus
269 * Allocate a new @mcb_bus.
271 struct mcb_bus *mcb_alloc_bus(struct device *carrier)
277 bus = kzalloc(sizeof(struct mcb_bus), GFP_KERNEL);
279 return ERR_PTR(-ENOMEM);
281 bus_nr = ida_simple_get(&mcb_ida, 0, 0, GFP_KERNEL);
284 return ERR_PTR(bus_nr);
287 bus->bus_nr = bus_nr;
288 bus->carrier = get_device(carrier);
290 device_initialize(&bus->dev);
291 bus->dev.parent = carrier;
292 bus->dev.bus = &mcb_bus_type;
293 bus->dev.type = &mcb_carrier_device_type;
294 bus->dev.release = &mcb_free_bus;
296 dev_set_name(&bus->dev, "mcb:%d", bus_nr);
297 rc = device_add(&bus->dev);
304 put_device(&bus->dev);
307 EXPORT_SYMBOL_NS_GPL(mcb_alloc_bus, MCB);
309 static int __mcb_devices_unregister(struct device *dev, void *data)
311 device_unregister(dev);
315 static void mcb_devices_unregister(struct mcb_bus *bus)
317 bus_for_each_dev(&mcb_bus_type, NULL, NULL, __mcb_devices_unregister);
320 * mcb_release_bus() - Free a @mcb_bus
321 * @bus: The @mcb_bus to release
323 * Release an allocated @mcb_bus from the system.
325 void mcb_release_bus(struct mcb_bus *bus)
327 mcb_devices_unregister(bus);
329 EXPORT_SYMBOL_NS_GPL(mcb_release_bus, MCB);
332 * mcb_bus_put() - Increment refcnt
335 * Get a @mcb_bus' ref
337 struct mcb_bus *mcb_bus_get(struct mcb_bus *bus)
340 get_device(&bus->dev);
344 EXPORT_SYMBOL_NS_GPL(mcb_bus_get, MCB);
347 * mcb_bus_put() - Decrement refcnt
350 * Release a @mcb_bus' ref
352 void mcb_bus_put(struct mcb_bus *bus)
355 put_device(&bus->dev);
357 EXPORT_SYMBOL_NS_GPL(mcb_bus_put, MCB);
360 * mcb_alloc_dev() - Allocate a device
361 * @bus: The @mcb_bus the device is part of
363 * Allocate a @mcb_device and add bus.
365 struct mcb_device *mcb_alloc_dev(struct mcb_bus *bus)
367 struct mcb_device *dev;
369 dev = kzalloc(sizeof(struct mcb_device), GFP_KERNEL);
377 EXPORT_SYMBOL_NS_GPL(mcb_alloc_dev, MCB);
380 * mcb_free_dev() - Free @mcb_device
381 * @dev: The device to free
385 void mcb_free_dev(struct mcb_device *dev)
389 EXPORT_SYMBOL_NS_GPL(mcb_free_dev, MCB);
391 static int __mcb_bus_add_devices(struct device *dev, void *data)
395 retval = device_attach(dev);
397 dev_err(dev, "Error adding device (%d)\n", retval);
405 * mcb_bus_add_devices() - Add devices in the bus' internal device list
406 * @bus: The @mcb_bus we add the devices
408 * Add devices in the bus' internal device list to the system.
410 void mcb_bus_add_devices(const struct mcb_bus *bus)
412 bus_for_each_dev(&mcb_bus_type, NULL, NULL, __mcb_bus_add_devices);
414 EXPORT_SYMBOL_NS_GPL(mcb_bus_add_devices, MCB);
417 * mcb_get_resource() - get a resource for a mcb device
418 * @dev: the mcb device
419 * @type: the type of resource
421 struct resource *mcb_get_resource(struct mcb_device *dev, unsigned int type)
423 if (type == IORESOURCE_MEM)
425 else if (type == IORESOURCE_IRQ)
430 EXPORT_SYMBOL_NS_GPL(mcb_get_resource, MCB);
433 * mcb_request_mem() - Request memory
434 * @dev: The @mcb_device the memory is for
435 * @name: The name for the memory reference.
437 * Request memory for a @mcb_device. If @name is NULL the driver name will
440 struct resource *mcb_request_mem(struct mcb_device *dev, const char *name)
442 struct resource *mem;
446 name = dev->dev.driver->name;
448 size = resource_size(&dev->mem);
450 mem = request_mem_region(dev->mem.start, size, name);
452 return ERR_PTR(-EBUSY);
456 EXPORT_SYMBOL_NS_GPL(mcb_request_mem, MCB);
459 * mcb_release_mem() - Release memory requested by device
460 * @dev: The @mcb_device that requested the memory
462 * Release memory that was prior requested via @mcb_request_mem().
464 void mcb_release_mem(struct resource *mem)
468 size = resource_size(mem);
469 release_mem_region(mem->start, size);
471 EXPORT_SYMBOL_NS_GPL(mcb_release_mem, MCB);
473 static int __mcb_get_irq(struct mcb_device *dev)
475 struct resource *irq;
477 irq = mcb_get_resource(dev, IORESOURCE_IRQ);
483 * mcb_get_irq() - Get device's IRQ number
484 * @dev: The @mcb_device the IRQ is for
486 * Get the IRQ number of a given @mcb_device.
488 int mcb_get_irq(struct mcb_device *dev)
490 struct mcb_bus *bus = dev->bus;
493 return bus->get_irq(dev);
495 return __mcb_get_irq(dev);
497 EXPORT_SYMBOL_NS_GPL(mcb_get_irq, MCB);
499 static int mcb_init(void)
501 return bus_register(&mcb_bus_type);
504 static void mcb_exit(void)
506 ida_destroy(&mcb_ida);
507 bus_unregister(&mcb_bus_type);
510 /* mcb must be initialized after PCI but before the chameleon drivers.
511 * That means we must use some initcall between subsys_initcall and
514 fs_initcall(mcb_init);
515 module_exit(mcb_exit);
517 MODULE_DESCRIPTION("MEN Chameleon Bus Driver");
518 MODULE_AUTHOR("Johannes Thumshirn <johannes.thumshirn@men.de>");
519 MODULE_LICENSE("GPL v2");