From 3764e82e5150d87b205c10cd78a9c9ab86fbfa51 Mon Sep 17 00:00:00 2001 From: Johannes Thumshirn Date: Wed, 26 Feb 2014 17:29:05 +0100 Subject: drivers: Introduce MEN Chameleon Bus The MCB (MEN Chameleon Bus) is a Bus specific to MEN Mikroelektronik FPGA based devices. It is used to identify MCB based IP-Cores within an FPGA and provide the necessary framework for instantiating drivers for these devices. Signed-off-by: Johannes Thumshirn Signed-off-by: Greg Kroah-Hartman --- drivers/mcb/mcb-core.c | 414 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 414 insertions(+) create mode 100644 drivers/mcb/mcb-core.c (limited to 'drivers/mcb/mcb-core.c') diff --git a/drivers/mcb/mcb-core.c b/drivers/mcb/mcb-core.c new file mode 100644 index 000000000000..bbe12932d404 --- /dev/null +++ b/drivers/mcb/mcb-core.c @@ -0,0 +1,414 @@ +/* + * MEN Chameleon Bus. + * + * Copyright (C) 2013 MEN Mikroelektronik GmbH (www.men.de) + * Author: Johannes Thumshirn + * + * 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 +#include +#include +#include +#include +#include + +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 "); +MODULE_LICENSE("GPL v2"); -- cgit v1.2.3-58-ga151