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(const struct device *dev, struct kobj_uevent_env *env)
46 const 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 void 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);
96 static void mcb_shutdown(struct device *dev)
98 struct mcb_driver *mdrv = to_mcb_driver(dev->driver);
99 struct mcb_device *mdev = to_mcb_device(dev);
101 if (mdrv && mdrv->shutdown)
102 mdrv->shutdown(mdev);
105 static ssize_t revision_show(struct device *dev, struct device_attribute *attr,
108 struct mcb_bus *bus = to_mcb_bus(dev);
110 return scnprintf(buf, PAGE_SIZE, "%d\n", bus->revision);
112 static DEVICE_ATTR_RO(revision);
114 static ssize_t model_show(struct device *dev, struct device_attribute *attr,
117 struct mcb_bus *bus = to_mcb_bus(dev);
119 return scnprintf(buf, PAGE_SIZE, "%c\n", bus->model);
121 static DEVICE_ATTR_RO(model);
123 static ssize_t minor_show(struct device *dev, struct device_attribute *attr,
126 struct mcb_bus *bus = to_mcb_bus(dev);
128 return scnprintf(buf, PAGE_SIZE, "%d\n", bus->minor);
130 static DEVICE_ATTR_RO(minor);
132 static ssize_t name_show(struct device *dev, struct device_attribute *attr,
135 struct mcb_bus *bus = to_mcb_bus(dev);
137 return scnprintf(buf, PAGE_SIZE, "%s\n", bus->name);
139 static DEVICE_ATTR_RO(name);
141 static struct attribute *mcb_bus_attrs[] = {
142 &dev_attr_revision.attr,
143 &dev_attr_model.attr,
144 &dev_attr_minor.attr,
149 static const struct attribute_group mcb_carrier_group = {
150 .attrs = mcb_bus_attrs,
153 static const struct attribute_group *mcb_carrier_groups[] = {
159 static struct bus_type mcb_bus_type = {
162 .uevent = mcb_uevent,
164 .remove = mcb_remove,
165 .shutdown = mcb_shutdown,
168 static struct device_type mcb_carrier_device_type = {
169 .name = "mcb-carrier",
170 .groups = mcb_carrier_groups,
174 * __mcb_register_driver() - Register a @mcb_driver at the system
175 * @drv: The @mcb_driver
176 * @owner: The @mcb_driver's module
177 * @mod_name: The name of the @mcb_driver's module
179 * Register a @mcb_driver at the system. Perform some sanity checks, if
180 * the .probe and .remove methods are provided by the driver.
182 int __mcb_register_driver(struct mcb_driver *drv, struct module *owner,
183 const char *mod_name)
185 if (!drv->probe || !drv->remove)
188 drv->driver.owner = owner;
189 drv->driver.bus = &mcb_bus_type;
190 drv->driver.mod_name = mod_name;
192 return driver_register(&drv->driver);
194 EXPORT_SYMBOL_NS_GPL(__mcb_register_driver, MCB);
197 * mcb_unregister_driver() - Unregister a @mcb_driver from the system
198 * @drv: The @mcb_driver
200 * Unregister a @mcb_driver from the system.
202 void mcb_unregister_driver(struct mcb_driver *drv)
204 driver_unregister(&drv->driver);
206 EXPORT_SYMBOL_NS_GPL(mcb_unregister_driver, MCB);
208 static void mcb_release_dev(struct device *dev)
210 struct mcb_device *mdev = to_mcb_device(dev);
212 mcb_bus_put(mdev->bus);
217 * mcb_device_register() - Register a mcb_device
218 * @bus: The @mcb_bus of the device
219 * @dev: The @mcb_device
221 * Register a specific @mcb_device at a @mcb_bus and the system itself.
223 int mcb_device_register(struct mcb_bus *bus, struct mcb_device *dev)
228 device_initialize(&dev->dev);
230 dev->dev.bus = &mcb_bus_type;
231 dev->dev.parent = bus->dev.parent;
232 dev->dev.release = mcb_release_dev;
233 dev->dma_dev = bus->carrier;
236 dev_set_name(&dev->dev, "mcb%d-16z%03d-%d:%d:%d",
237 bus->bus_nr, device_id, dev->inst, dev->group, dev->var);
239 ret = device_add(&dev->dev);
241 pr_err("Failed registering device 16z%03d on bus mcb%d (%d)\n",
242 device_id, bus->bus_nr, ret);
249 put_device(&dev->dev);
253 EXPORT_SYMBOL_NS_GPL(mcb_device_register, MCB);
255 static void mcb_free_bus(struct device *dev)
257 struct mcb_bus *bus = to_mcb_bus(dev);
259 put_device(bus->carrier);
260 ida_free(&mcb_ida, bus->bus_nr);
265 * mcb_alloc_bus() - Allocate a new @mcb_bus
267 * Allocate a new @mcb_bus.
269 struct mcb_bus *mcb_alloc_bus(struct device *carrier)
275 bus = kzalloc(sizeof(struct mcb_bus), GFP_KERNEL);
277 return ERR_PTR(-ENOMEM);
279 bus_nr = ida_alloc(&mcb_ida, GFP_KERNEL);
282 return ERR_PTR(bus_nr);
285 bus->bus_nr = bus_nr;
286 bus->carrier = get_device(carrier);
288 device_initialize(&bus->dev);
289 bus->dev.parent = carrier;
290 bus->dev.bus = &mcb_bus_type;
291 bus->dev.type = &mcb_carrier_device_type;
292 bus->dev.release = mcb_free_bus;
294 dev_set_name(&bus->dev, "mcb:%d", bus_nr);
295 rc = device_add(&bus->dev);
302 put_device(&bus->dev);
305 EXPORT_SYMBOL_NS_GPL(mcb_alloc_bus, MCB);
307 static int __mcb_devices_unregister(struct device *dev, void *data)
309 device_unregister(dev);
313 static void mcb_devices_unregister(struct mcb_bus *bus)
315 bus_for_each_dev(bus->dev.bus, NULL, NULL, __mcb_devices_unregister);
318 * mcb_release_bus() - Free a @mcb_bus
319 * @bus: The @mcb_bus to release
321 * Release an allocated @mcb_bus from the system.
323 void mcb_release_bus(struct mcb_bus *bus)
325 mcb_devices_unregister(bus);
327 EXPORT_SYMBOL_NS_GPL(mcb_release_bus, MCB);
330 * mcb_bus_put() - Increment refcnt
333 * Get a @mcb_bus' ref
335 struct mcb_bus *mcb_bus_get(struct mcb_bus *bus)
338 get_device(&bus->dev);
342 EXPORT_SYMBOL_NS_GPL(mcb_bus_get, MCB);
345 * mcb_bus_put() - Decrement refcnt
348 * Release a @mcb_bus' ref
350 void mcb_bus_put(struct mcb_bus *bus)
353 put_device(&bus->dev);
355 EXPORT_SYMBOL_NS_GPL(mcb_bus_put, MCB);
358 * mcb_alloc_dev() - Allocate a device
359 * @bus: The @mcb_bus the device is part of
361 * Allocate a @mcb_device and add bus.
363 struct mcb_device *mcb_alloc_dev(struct mcb_bus *bus)
365 struct mcb_device *dev;
367 dev = kzalloc(sizeof(struct mcb_device), GFP_KERNEL);
375 EXPORT_SYMBOL_NS_GPL(mcb_alloc_dev, MCB);
378 * mcb_free_dev() - Free @mcb_device
379 * @dev: The device to free
383 void mcb_free_dev(struct mcb_device *dev)
387 EXPORT_SYMBOL_NS_GPL(mcb_free_dev, MCB);
389 static int __mcb_bus_add_devices(struct device *dev, void *data)
393 retval = device_attach(dev);
395 dev_err(dev, "Error adding device (%d)\n", retval);
403 * mcb_bus_add_devices() - Add devices in the bus' internal device list
404 * @bus: The @mcb_bus we add the devices
406 * Add devices in the bus' internal device list to the system.
408 void mcb_bus_add_devices(const struct mcb_bus *bus)
410 bus_for_each_dev(bus->dev.bus, NULL, NULL, __mcb_bus_add_devices);
412 EXPORT_SYMBOL_NS_GPL(mcb_bus_add_devices, MCB);
415 * mcb_get_resource() - get a resource for a mcb device
416 * @dev: the mcb device
417 * @type: the type of resource
419 struct resource *mcb_get_resource(struct mcb_device *dev, unsigned int type)
421 if (type == IORESOURCE_MEM)
423 else if (type == IORESOURCE_IRQ)
428 EXPORT_SYMBOL_NS_GPL(mcb_get_resource, MCB);
431 * mcb_request_mem() - Request memory
432 * @dev: The @mcb_device the memory is for
433 * @name: The name for the memory reference.
435 * Request memory for a @mcb_device. If @name is NULL the driver name will
438 struct resource *mcb_request_mem(struct mcb_device *dev, const char *name)
440 struct resource *mem;
444 name = dev->dev.driver->name;
446 size = resource_size(&dev->mem);
448 mem = request_mem_region(dev->mem.start, size, name);
450 return ERR_PTR(-EBUSY);
454 EXPORT_SYMBOL_NS_GPL(mcb_request_mem, MCB);
457 * mcb_release_mem() - Release memory requested by device
458 * @dev: The @mcb_device that requested the memory
460 * Release memory that was prior requested via @mcb_request_mem().
462 void mcb_release_mem(struct resource *mem)
466 size = resource_size(mem);
467 release_mem_region(mem->start, size);
469 EXPORT_SYMBOL_NS_GPL(mcb_release_mem, MCB);
471 static int __mcb_get_irq(struct mcb_device *dev)
473 struct resource *irq;
475 irq = mcb_get_resource(dev, IORESOURCE_IRQ);
481 * mcb_get_irq() - Get device's IRQ number
482 * @dev: The @mcb_device the IRQ is for
484 * Get the IRQ number of a given @mcb_device.
486 int mcb_get_irq(struct mcb_device *dev)
488 struct mcb_bus *bus = dev->bus;
491 return bus->get_irq(dev);
493 return __mcb_get_irq(dev);
495 EXPORT_SYMBOL_NS_GPL(mcb_get_irq, MCB);
497 static int mcb_init(void)
499 return bus_register(&mcb_bus_type);
502 static void mcb_exit(void)
504 ida_destroy(&mcb_ida);
505 bus_unregister(&mcb_bus_type);
508 /* mcb must be initialized after PCI but before the chameleon drivers.
509 * That means we must use some initcall between subsys_initcall and
512 fs_initcall(mcb_init);
513 module_exit(mcb_exit);
515 MODULE_DESCRIPTION("MEN Chameleon Bus Driver");
516 MODULE_AUTHOR("Johannes Thumshirn <johannes.thumshirn@men.de>");
517 MODULE_LICENSE("GPL v2");