linux/drivers/misc/pvpanic/pvpanic.c
Christophe JAILLET d208cbb002 misc/pvpanic: Remove some dead-code
'pvpanic_remove()' is referenced only by a 'devm_add_action_or_reset()'
call in 'devm_pvpanic_probe()'. So, we know that its parameter is non-NULL.

Axe the unneeded check to save a few lines of code.

Suggested-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Link: https://lore.kernel.org/r/8e425618f4042a8ab8366be4d34026972e77bd40.1622911768.git.christophe.jaillet@wanadoo.fr
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-06-09 14:45:33 +02:00

111 lines
2.3 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* Pvpanic Device Support
*
* Copyright (C) 2013 Fujitsu.
* Copyright (C) 2018 ZTE.
* Copyright (C) 2021 Oracle.
*/
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/kexec.h>
#include <linux/mod_devicetable.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/types.h>
#include <linux/cdev.h>
#include <linux/list.h>
#include <uapi/misc/pvpanic.h>
#include "pvpanic.h"
MODULE_AUTHOR("Mihai Carabas <mihai.carabas@oracle.com>");
MODULE_DESCRIPTION("pvpanic device driver ");
MODULE_LICENSE("GPL");
static struct list_head pvpanic_list;
static spinlock_t pvpanic_lock;
static void
pvpanic_send_event(unsigned int event)
{
struct pvpanic_instance *pi_cur;
spin_lock(&pvpanic_lock);
list_for_each_entry(pi_cur, &pvpanic_list, list) {
if (event & pi_cur->capability & pi_cur->events)
iowrite8(event, pi_cur->base);
}
spin_unlock(&pvpanic_lock);
}
static int
pvpanic_panic_notify(struct notifier_block *nb, unsigned long code,
void *unused)
{
unsigned int event = PVPANIC_PANICKED;
if (kexec_crash_loaded())
event = PVPANIC_CRASH_LOADED;
pvpanic_send_event(event);
return NOTIFY_DONE;
}
static struct notifier_block pvpanic_panic_nb = {
.notifier_call = pvpanic_panic_notify,
.priority = 1, /* let this called before broken drm_fb_helper */
};
static void pvpanic_remove(void *param)
{
struct pvpanic_instance *pi_cur, *pi_next;
struct pvpanic_instance *pi = param;
spin_lock(&pvpanic_lock);
list_for_each_entry_safe(pi_cur, pi_next, &pvpanic_list, list) {
if (pi_cur == pi) {
list_del(&pi_cur->list);
break;
}
}
spin_unlock(&pvpanic_lock);
}
int devm_pvpanic_probe(struct device *dev, struct pvpanic_instance *pi)
{
if (!pi || !pi->base)
return -EINVAL;
spin_lock(&pvpanic_lock);
list_add(&pi->list, &pvpanic_list);
spin_unlock(&pvpanic_lock);
return devm_add_action_or_reset(dev, pvpanic_remove, pi);
}
EXPORT_SYMBOL_GPL(devm_pvpanic_probe);
static int pvpanic_init(void)
{
INIT_LIST_HEAD(&pvpanic_list);
spin_lock_init(&pvpanic_lock);
atomic_notifier_chain_register(&panic_notifier_list,
&pvpanic_panic_nb);
return 0;
}
static void pvpanic_exit(void)
{
atomic_notifier_chain_unregister(&panic_notifier_list,
&pvpanic_panic_nb);
}
module_init(pvpanic_init);
module_exit(pvpanic_exit);