https://github.com/torvalds/linux
Tip revision: 6eaae198076080886b9e7d57f4ae06fa782f90ef authored by Linus Torvalds on 23 July 2023, 22:24:10 UTC
Linux 6.5-rc3
Linux 6.5-rc3
Tip revision: 6eaae19
superhyway.c
/*
* drivers/sh/superhyway/superhyway.c
*
* SuperHyway Bus Driver
*
* Copyright (C) 2004, 2005 Paul Mundt <lethal@linux-sh.org>
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*/
#include <linux/kernel.h>
#include <linux/device.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/types.h>
#include <linux/list.h>
#include <linux/superhyway.h>
#include <linux/string.h>
#include <linux/slab.h>
static int superhyway_devices;
static struct device superhyway_bus_device = {
.init_name = "superhyway",
};
static void superhyway_device_release(struct device *dev)
{
struct superhyway_device *sdev = to_superhyway_device(dev);
kfree(sdev->resource);
kfree(sdev);
}
/**
* superhyway_add_device - Add a SuperHyway module
* @base: Physical address where module is mapped.
* @sdev: SuperHyway device to add, or NULL to allocate a new one.
* @bus: Bus where SuperHyway module resides.
*
* This is responsible for adding a new SuperHyway module. This sets up a new
* struct superhyway_device for the module being added if @sdev == NULL.
*
* Devices are initially added in the order that they are scanned (from the
* top-down of the memory map), and are assigned an ID based on the order that
* they are added. Any manual addition of a module will thus get the ID after
* the devices already discovered regardless of where it resides in memory.
*
* Further work can and should be done in superhyway_scan_bus(), to be sure
* that any new modules are properly discovered and subsequently registered.
*/
int superhyway_add_device(unsigned long base, struct superhyway_device *sdev,
struct superhyway_bus *bus)
{
struct superhyway_device *dev = sdev;
if (!dev) {
dev = kzalloc(sizeof(struct superhyway_device), GFP_KERNEL);
if (!dev)
return -ENOMEM;
}
dev->bus = bus;
superhyway_read_vcr(dev, base, &dev->vcr);
if (!dev->resource) {
dev->resource = kzalloc(sizeof(struct resource), GFP_KERNEL);
if (!dev->resource) {
kfree(dev);
return -ENOMEM;
}
dev->resource->name = dev->name;
dev->resource->start = base;
dev->resource->end = dev->resource->start + 0x01000000;
}
dev->dev.parent = &superhyway_bus_device;
dev->dev.bus = &superhyway_bus_type;
dev->dev.release = superhyway_device_release;
dev->id.id = dev->vcr.mod_id;
sprintf(dev->name, "SuperHyway device %04x", dev->id.id);
dev_set_name(&dev->dev, "%02x", superhyway_devices);
superhyway_devices++;
return device_register(&dev->dev);
}
int superhyway_add_devices(struct superhyway_bus *bus,
struct superhyway_device **devices,
int nr_devices)
{
int i, ret = 0;
for (i = 0; i < nr_devices; i++) {
struct superhyway_device *dev = devices[i];
ret |= superhyway_add_device(dev->resource[0].start, dev, bus);
}
return ret;
}
static int __init superhyway_init(void)
{
struct superhyway_bus *bus;
int ret;
ret = device_register(&superhyway_bus_device);
if (unlikely(ret))
return ret;
for (bus = superhyway_channels; bus->ops; bus++)
ret |= superhyway_scan_bus(bus);
return ret;
}
postcore_initcall(superhyway_init);
static const struct superhyway_device_id *
superhyway_match_id(const struct superhyway_device_id *ids,
struct superhyway_device *dev)
{
while (ids->id) {
if (ids->id == dev->id.id)
return ids;
ids++;
}
return NULL;
}
static int superhyway_device_probe(struct device *dev)
{
struct superhyway_device *shyway_dev = to_superhyway_device(dev);
struct superhyway_driver *shyway_drv = to_superhyway_driver(dev->driver);
if (shyway_drv && shyway_drv->probe) {
const struct superhyway_device_id *id;
id = superhyway_match_id(shyway_drv->id_table, shyway_dev);
if (id)
return shyway_drv->probe(shyway_dev, id);
}
return -ENODEV;
}
static void superhyway_device_remove(struct device *dev)
{
struct superhyway_device *shyway_dev = to_superhyway_device(dev);
struct superhyway_driver *shyway_drv = to_superhyway_driver(dev->driver);
if (shyway_drv->remove)
shyway_drv->remove(shyway_dev);
}
/**
* superhyway_register_driver - Register a new SuperHyway driver
* @drv: SuperHyway driver to register.
*
* This registers the passed in @drv. Any devices matching the id table will
* automatically be populated and handed off to the driver's specified probe
* routine.
*/
int superhyway_register_driver(struct superhyway_driver *drv)
{
drv->drv.name = drv->name;
drv->drv.bus = &superhyway_bus_type;
return driver_register(&drv->drv);
}
/**
* superhyway_unregister_driver - Unregister a SuperHyway driver
* @drv: SuperHyway driver to unregister.
*
* This cleans up after superhyway_register_driver(), and should be invoked in
* the exit path of any module drivers.
*/
void superhyway_unregister_driver(struct superhyway_driver *drv)
{
driver_unregister(&drv->drv);
}
static int superhyway_bus_match(struct device *dev, struct device_driver *drv)
{
struct superhyway_device *shyway_dev = to_superhyway_device(dev);
struct superhyway_driver *shyway_drv = to_superhyway_driver(drv);
const struct superhyway_device_id *ids = shyway_drv->id_table;
if (!ids)
return -EINVAL;
if (superhyway_match_id(ids, shyway_dev))
return 1;
return -ENODEV;
}
struct bus_type superhyway_bus_type = {
.name = "superhyway",
.match = superhyway_bus_match,
#ifdef CONFIG_SYSFS
.dev_groups = superhyway_dev_groups,
#endif
.probe = superhyway_device_probe,
.remove = superhyway_device_remove,
};
static int __init superhyway_bus_init(void)
{
return bus_register(&superhyway_bus_type);
}
static void __exit superhyway_bus_exit(void)
{
device_unregister(&superhyway_bus_device);
bus_unregister(&superhyway_bus_type);
}
core_initcall(superhyway_bus_init);
module_exit(superhyway_bus_exit);
EXPORT_SYMBOL(superhyway_bus_type);
EXPORT_SYMBOL(superhyway_add_device);
EXPORT_SYMBOL(superhyway_add_devices);
EXPORT_SYMBOL(superhyway_register_driver);
EXPORT_SYMBOL(superhyway_unregister_driver);
MODULE_LICENSE("GPL");