linux_dsm_epyc7002/drivers/nubus/bus.c
Finn Thain bdeeed0988 nubus: Call bus_register unconditionally
Loading a NuBus driver module on a non-NuBus machine triggers the
BUG_ON(!drv->bus->p) in driver_register(), because bus_register() was
not called, because it is conditional on MACH_IS_MAC.

Fix the crash by calling bus_register() unconditionally. Call it from
a postcore_initcall(), like other busses do.

Hence, the bus type is available for device_register(), which happens
in a subsys initcall, and for driver_register(), which happens in a
device or module initcall.

Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reported-by: Michael Schmitz <schmitzmic@gmail.com>
Tested-by: Stan Johnson <userm57@yahoo.com>
Fixes: 7f86c765a6 ("nubus: Add support for the driver model")
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-14 16:27:08 +02:00

113 lines
2.6 KiB
C

// SPDX-License-Identifier: GPL-2.0
//
// Bus implementation for the NuBus subsystem.
//
// Copyright (C) 2017 Finn Thain
#include <linux/device.h>
#include <linux/list.h>
#include <linux/nubus.h>
#include <linux/seq_file.h>
#include <linux/slab.h>
#define to_nubus_board(d) container_of(d, struct nubus_board, dev)
#define to_nubus_driver(d) container_of(d, struct nubus_driver, driver)
static int nubus_bus_match(struct device *dev, struct device_driver *driver)
{
return 1;
}
static int nubus_device_probe(struct device *dev)
{
struct nubus_driver *ndrv = to_nubus_driver(dev->driver);
int err = -ENODEV;
if (ndrv->probe)
err = ndrv->probe(to_nubus_board(dev));
return err;
}
static int nubus_device_remove(struct device *dev)
{
struct nubus_driver *ndrv = to_nubus_driver(dev->driver);
int err = -ENODEV;
if (dev->driver && ndrv->remove)
err = ndrv->remove(to_nubus_board(dev));
return err;
}
struct bus_type nubus_bus_type = {
.name = "nubus",
.match = nubus_bus_match,
.probe = nubus_device_probe,
.remove = nubus_device_remove,
};
EXPORT_SYMBOL(nubus_bus_type);
int nubus_driver_register(struct nubus_driver *ndrv)
{
ndrv->driver.bus = &nubus_bus_type;
return driver_register(&ndrv->driver);
}
EXPORT_SYMBOL(nubus_driver_register);
void nubus_driver_unregister(struct nubus_driver *ndrv)
{
driver_unregister(&ndrv->driver);
}
EXPORT_SYMBOL(nubus_driver_unregister);
static struct device nubus_parent = {
.init_name = "nubus",
};
static int __init nubus_bus_register(void)
{
return bus_register(&nubus_bus_type);
}
postcore_initcall(nubus_bus_register);
int __init nubus_parent_device_register(void)
{
return device_register(&nubus_parent);
}
static void nubus_device_release(struct device *dev)
{
struct nubus_board *board = to_nubus_board(dev);
struct nubus_rsrc *fres, *tmp;
list_for_each_entry_safe(fres, tmp, &nubus_func_rsrcs, list)
if (fres->board == board) {
list_del(&fres->list);
kfree(fres);
}
kfree(board);
}
int nubus_device_register(struct nubus_board *board)
{
board->dev.parent = &nubus_parent;
board->dev.release = nubus_device_release;
board->dev.bus = &nubus_bus_type;
dev_set_name(&board->dev, "slot.%X", board->slot);
return device_register(&board->dev);
}
static int nubus_print_device_name_fn(struct device *dev, void *data)
{
struct nubus_board *board = to_nubus_board(dev);
struct seq_file *m = data;
seq_printf(m, "Slot %X: %s\n", board->slot, board->name);
return 0;
}
int nubus_proc_show(struct seq_file *m, void *data)
{
return bus_for_each_dev(&nubus_bus_type, NULL, m,
nubus_print_device_name_fn);
}