|  | /* | 
|  | * MEN Chameleon Bus. | 
|  | * | 
|  | * Copyright (C) 2013 MEN Mikroelektronik GmbH (www.men.de) | 
|  | * Author: Johannes Thumshirn <johannes.thumshirn@men.de> | 
|  | * | 
|  | * This program is free software; you can redistribute it and/or modify it | 
|  | * under the terms of the GNU General Public License as published by the Free | 
|  | * Software Foundation; version 2 of the License. | 
|  | */ | 
|  | #include <linux/kernel.h> | 
|  | #include <linux/module.h> | 
|  | #include <linux/slab.h> | 
|  | #include <linux/types.h> | 
|  | #include <linux/idr.h> | 
|  | #include <linux/mcb.h> | 
|  |  | 
|  | static DEFINE_IDA(mcb_ida); | 
|  |  | 
|  | static const struct mcb_device_id *mcb_match_id(const struct mcb_device_id *ids, | 
|  | struct mcb_device *dev) | 
|  | { | 
|  | if (ids) { | 
|  | while (ids->device) { | 
|  | if (ids->device == dev->id) | 
|  | return ids; | 
|  | ids++; | 
|  | } | 
|  | } | 
|  |  | 
|  | return NULL; | 
|  | } | 
|  |  | 
|  | static int mcb_match(struct device *dev, struct device_driver *drv) | 
|  | { | 
|  | struct mcb_driver *mdrv = to_mcb_driver(drv); | 
|  | struct mcb_device *mdev = to_mcb_device(dev); | 
|  | const struct mcb_device_id *found_id; | 
|  |  | 
|  | found_id = mcb_match_id(mdrv->id_table, mdev); | 
|  | if (found_id) | 
|  | return 1; | 
|  |  | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | static int mcb_uevent(struct device *dev, struct kobj_uevent_env *env) | 
|  | { | 
|  | struct mcb_device *mdev = to_mcb_device(dev); | 
|  | int ret; | 
|  |  | 
|  | ret = add_uevent_var(env, "MODALIAS=mcb:16z%03d", mdev->id); | 
|  | if (ret) | 
|  | return -ENOMEM; | 
|  |  | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | static int mcb_probe(struct device *dev) | 
|  | { | 
|  | struct mcb_driver *mdrv = to_mcb_driver(dev->driver); | 
|  | struct mcb_device *mdev = to_mcb_device(dev); | 
|  | const struct mcb_device_id *found_id; | 
|  |  | 
|  | found_id = mcb_match_id(mdrv->id_table, mdev); | 
|  | if (!found_id) | 
|  | return -ENODEV; | 
|  |  | 
|  | return mdrv->probe(mdev, found_id); | 
|  | } | 
|  |  | 
|  | static int mcb_remove(struct device *dev) | 
|  | { | 
|  | struct mcb_driver *mdrv = to_mcb_driver(dev->driver); | 
|  | struct mcb_device *mdev = to_mcb_device(dev); | 
|  |  | 
|  | mdrv->remove(mdev); | 
|  |  | 
|  | put_device(&mdev->dev); | 
|  |  | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | static void mcb_shutdown(struct device *dev) | 
|  | { | 
|  | struct mcb_device *mdev = to_mcb_device(dev); | 
|  | struct mcb_driver *mdrv = mdev->driver; | 
|  |  | 
|  | if (mdrv && mdrv->shutdown) | 
|  | mdrv->shutdown(mdev); | 
|  | } | 
|  |  | 
|  | static struct bus_type mcb_bus_type = { | 
|  | .name = "mcb", | 
|  | .match = mcb_match, | 
|  | .uevent = mcb_uevent, | 
|  | .probe = mcb_probe, | 
|  | .remove = mcb_remove, | 
|  | .shutdown = mcb_shutdown, | 
|  | }; | 
|  |  | 
|  | /** | 
|  | * __mcb_register_driver() - Register a @mcb_driver at the system | 
|  | * @drv: The @mcb_driver | 
|  | * @owner: The @mcb_driver's module | 
|  | * @mod_name: The name of the @mcb_driver's module | 
|  | * | 
|  | * Register a @mcb_driver at the system. Perform some sanity checks, if | 
|  | * the .probe and .remove methods are provided by the driver. | 
|  | */ | 
|  | int __mcb_register_driver(struct mcb_driver *drv, struct module *owner, | 
|  | const char *mod_name) | 
|  | { | 
|  | if (!drv->probe || !drv->remove) | 
|  | return -EINVAL; | 
|  |  | 
|  | drv->driver.owner = owner; | 
|  | drv->driver.bus = &mcb_bus_type; | 
|  | drv->driver.mod_name = mod_name; | 
|  |  | 
|  | return driver_register(&drv->driver); | 
|  | } | 
|  | EXPORT_SYMBOL_GPL(__mcb_register_driver); | 
|  |  | 
|  | /** | 
|  | * mcb_unregister_driver() - Unregister a @mcb_driver from the system | 
|  | * @drv: The @mcb_driver | 
|  | * | 
|  | * Unregister a @mcb_driver from the system. | 
|  | */ | 
|  | void mcb_unregister_driver(struct mcb_driver *drv) | 
|  | { | 
|  | driver_unregister(&drv->driver); | 
|  | } | 
|  | EXPORT_SYMBOL_GPL(mcb_unregister_driver); | 
|  |  | 
|  | static void mcb_release_dev(struct device *dev) | 
|  | { | 
|  | struct mcb_device *mdev = to_mcb_device(dev); | 
|  |  | 
|  | mcb_bus_put(mdev->bus); | 
|  | kfree(mdev); | 
|  | } | 
|  |  | 
|  | /** | 
|  | * mcb_device_register() - Register a mcb_device | 
|  | * @bus: The @mcb_bus of the device | 
|  | * @dev: The @mcb_device | 
|  | * | 
|  | * Register a specific @mcb_device at a @mcb_bus and the system itself. | 
|  | */ | 
|  | int mcb_device_register(struct mcb_bus *bus, struct mcb_device *dev) | 
|  | { | 
|  | int ret; | 
|  | int device_id; | 
|  |  | 
|  | device_initialize(&dev->dev); | 
|  | dev->dev.bus = &mcb_bus_type; | 
|  | dev->dev.parent = bus->dev.parent; | 
|  | dev->dev.release = mcb_release_dev; | 
|  |  | 
|  | device_id = dev->id; | 
|  | dev_set_name(&dev->dev, "mcb%d-16z%03d-%d:%d:%d", | 
|  | bus->bus_nr, device_id, dev->inst, dev->group, dev->var); | 
|  |  | 
|  | ret = device_add(&dev->dev); | 
|  | if (ret < 0) { | 
|  | pr_err("Failed registering device 16z%03d on bus mcb%d (%d)\n", | 
|  | device_id, bus->bus_nr, ret); | 
|  | goto out; | 
|  | } | 
|  |  | 
|  | return 0; | 
|  |  | 
|  | out: | 
|  |  | 
|  | return ret; | 
|  | } | 
|  | EXPORT_SYMBOL_GPL(mcb_device_register); | 
|  |  | 
|  | /** | 
|  | * mcb_alloc_bus() - Allocate a new @mcb_bus | 
|  | * | 
|  | * Allocate a new @mcb_bus. | 
|  | */ | 
|  | struct mcb_bus *mcb_alloc_bus(void) | 
|  | { | 
|  | struct mcb_bus *bus; | 
|  | int bus_nr; | 
|  |  | 
|  | bus = kzalloc(sizeof(struct mcb_bus), GFP_KERNEL); | 
|  | if (!bus) | 
|  | return NULL; | 
|  |  | 
|  | bus_nr = ida_simple_get(&mcb_ida, 0, 0, GFP_KERNEL); | 
|  | if (bus_nr < 0) { | 
|  | kfree(bus); | 
|  | return ERR_PTR(bus_nr); | 
|  | } | 
|  |  | 
|  | INIT_LIST_HEAD(&bus->children); | 
|  | bus->bus_nr = bus_nr; | 
|  |  | 
|  | return bus; | 
|  | } | 
|  | EXPORT_SYMBOL_GPL(mcb_alloc_bus); | 
|  |  | 
|  | static int __mcb_devices_unregister(struct device *dev, void *data) | 
|  | { | 
|  | device_unregister(dev); | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | static void mcb_devices_unregister(struct mcb_bus *bus) | 
|  | { | 
|  | bus_for_each_dev(&mcb_bus_type, NULL, NULL, __mcb_devices_unregister); | 
|  | } | 
|  | /** | 
|  | * mcb_release_bus() - Free a @mcb_bus | 
|  | * @bus: The @mcb_bus to release | 
|  | * | 
|  | * Release an allocated @mcb_bus from the system. | 
|  | */ | 
|  | void mcb_release_bus(struct mcb_bus *bus) | 
|  | { | 
|  | mcb_devices_unregister(bus); | 
|  |  | 
|  | ida_simple_remove(&mcb_ida, bus->bus_nr); | 
|  |  | 
|  | kfree(bus); | 
|  | } | 
|  | EXPORT_SYMBOL_GPL(mcb_release_bus); | 
|  |  | 
|  | /** | 
|  | * mcb_bus_put() - Increment refcnt | 
|  | * @bus: The @mcb_bus | 
|  | * | 
|  | * Get a @mcb_bus' ref | 
|  | */ | 
|  | struct mcb_bus *mcb_bus_get(struct mcb_bus *bus) | 
|  | { | 
|  | if (bus) | 
|  | get_device(&bus->dev); | 
|  |  | 
|  | return bus; | 
|  | } | 
|  | EXPORT_SYMBOL_GPL(mcb_bus_get); | 
|  |  | 
|  | /** | 
|  | * mcb_bus_put() - Decrement refcnt | 
|  | * @bus: The @mcb_bus | 
|  | * | 
|  | * Release a @mcb_bus' ref | 
|  | */ | 
|  | void mcb_bus_put(struct mcb_bus *bus) | 
|  | { | 
|  | if (bus) | 
|  | put_device(&bus->dev); | 
|  | } | 
|  | EXPORT_SYMBOL_GPL(mcb_bus_put); | 
|  |  | 
|  | /** | 
|  | * mcb_alloc_dev() - Allocate a device | 
|  | * @bus: The @mcb_bus the device is part of | 
|  | * | 
|  | * Allocate a @mcb_device and add bus. | 
|  | */ | 
|  | struct mcb_device *mcb_alloc_dev(struct mcb_bus *bus) | 
|  | { | 
|  | struct mcb_device *dev; | 
|  |  | 
|  | dev = kzalloc(sizeof(struct mcb_device), GFP_KERNEL); | 
|  | if (!dev) | 
|  | return NULL; | 
|  |  | 
|  | INIT_LIST_HEAD(&dev->bus_list); | 
|  | dev->bus = bus; | 
|  |  | 
|  | return dev; | 
|  | } | 
|  | EXPORT_SYMBOL_GPL(mcb_alloc_dev); | 
|  |  | 
|  | /** | 
|  | * mcb_free_dev() - Free @mcb_device | 
|  | * @dev: The device to free | 
|  | * | 
|  | * Free a @mcb_device | 
|  | */ | 
|  | void mcb_free_dev(struct mcb_device *dev) | 
|  | { | 
|  | kfree(dev); | 
|  | } | 
|  | EXPORT_SYMBOL_GPL(mcb_free_dev); | 
|  |  | 
|  | static int __mcb_bus_add_devices(struct device *dev, void *data) | 
|  | { | 
|  | struct mcb_device *mdev = to_mcb_device(dev); | 
|  | int retval; | 
|  |  | 
|  | if (mdev->is_added) | 
|  | return 0; | 
|  |  | 
|  | retval = device_attach(dev); | 
|  | if (retval < 0) | 
|  | dev_err(dev, "Error adding device (%d)\n", retval); | 
|  |  | 
|  | mdev->is_added = true; | 
|  |  | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | static int __mcb_bus_add_child(struct device *dev, void *data) | 
|  | { | 
|  | struct mcb_device *mdev = to_mcb_device(dev); | 
|  | struct mcb_bus *child; | 
|  |  | 
|  | BUG_ON(!mdev->is_added); | 
|  | child = mdev->subordinate; | 
|  |  | 
|  | if (child) | 
|  | mcb_bus_add_devices(child); | 
|  |  | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | /** | 
|  | * mcb_bus_add_devices() - Add devices in the bus' internal device list | 
|  | * @bus: The @mcb_bus we add the devices | 
|  | * | 
|  | * Add devices in the bus' internal device list to the system. | 
|  | */ | 
|  | void mcb_bus_add_devices(const struct mcb_bus *bus) | 
|  | { | 
|  | bus_for_each_dev(&mcb_bus_type, NULL, NULL, __mcb_bus_add_devices); | 
|  | bus_for_each_dev(&mcb_bus_type, NULL, NULL, __mcb_bus_add_child); | 
|  |  | 
|  | } | 
|  | EXPORT_SYMBOL_GPL(mcb_bus_add_devices); | 
|  |  | 
|  | /** | 
|  | * mcb_request_mem() - Request memory | 
|  | * @dev: The @mcb_device the memory is for | 
|  | * @name: The name for the memory reference. | 
|  | * | 
|  | * Request memory for a @mcb_device. If @name is NULL the driver name will | 
|  | * be used. | 
|  | */ | 
|  | struct resource *mcb_request_mem(struct mcb_device *dev, const char *name) | 
|  | { | 
|  | struct resource *mem; | 
|  | u32 size; | 
|  |  | 
|  | if (!name) | 
|  | name = dev->dev.driver->name; | 
|  |  | 
|  | size = resource_size(&dev->mem); | 
|  |  | 
|  | mem = request_mem_region(dev->mem.start, size, name); | 
|  | if (!mem) | 
|  | return ERR_PTR(-EBUSY); | 
|  |  | 
|  | return mem; | 
|  | } | 
|  | EXPORT_SYMBOL_GPL(mcb_request_mem); | 
|  |  | 
|  | /** | 
|  | * mcb_release_mem() - Release memory requested by device | 
|  | * @dev: The @mcb_device that requested the memory | 
|  | * | 
|  | * Release memory that was prior requested via @mcb_request_mem(). | 
|  | */ | 
|  | void mcb_release_mem(struct resource *mem) | 
|  | { | 
|  | u32 size; | 
|  |  | 
|  | size = resource_size(mem); | 
|  | release_mem_region(mem->start, size); | 
|  | } | 
|  | EXPORT_SYMBOL_GPL(mcb_release_mem); | 
|  |  | 
|  | /** | 
|  | * mcb_get_irq() - Get device's IRQ number | 
|  | * @dev: The @mcb_device the IRQ is for | 
|  | * | 
|  | * Get the IRQ number of a given @mcb_device. | 
|  | */ | 
|  | int mcb_get_irq(struct mcb_device *dev) | 
|  | { | 
|  | struct resource *irq = &dev->irq; | 
|  |  | 
|  | return irq->start; | 
|  | } | 
|  | EXPORT_SYMBOL_GPL(mcb_get_irq); | 
|  |  | 
|  | static int mcb_init(void) | 
|  | { | 
|  | return bus_register(&mcb_bus_type); | 
|  | } | 
|  |  | 
|  | static void mcb_exit(void) | 
|  | { | 
|  | bus_unregister(&mcb_bus_type); | 
|  | } | 
|  |  | 
|  | /* mcb must be initialized after PCI but before the chameleon drivers. | 
|  | * That means we must use some initcall between subsys_initcall and | 
|  | * device_initcall. | 
|  | */ | 
|  | fs_initcall(mcb_init); | 
|  | module_exit(mcb_exit); | 
|  |  | 
|  | MODULE_DESCRIPTION("MEN Chameleon Bus Driver"); | 
|  | MODULE_AUTHOR("Johannes Thumshirn <johannes.thumshirn@men.de>"); | 
|  | MODULE_LICENSE("GPL v2"); |