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// SPDX-License-Identifier: GPL-2.0-only
// Copyright (C) 2022 Linutronix GmbH, John Ogness
// Copyright (C) 2022 Intel, Thomas Gleixner
#include <linux/kernel.h>
#include <linux/console.h>
#include "internal.h"
/*
* Printk console printing implementation for consoles which does not depend
* on the legacy style console_lock mechanism.
*/
/**
* nbcon_state_set - Helper function to set the console state
* @con: Console to update
* @new: The new state to write
*
* Only to be used when the console is not yet or no longer visible in the
* system. Otherwise use nbcon_state_try_cmpxchg().
*/
static inline void nbcon_state_set(struct console *con, struct nbcon_state *new)
{
atomic_set(&ACCESS_PRIVATE(con, nbcon_state), new->atom);
}
/**
* nbcon_state_read - Helper function to read the console state
* @con: Console to read
* @state: The state to store the result
*/
static inline void nbcon_state_read(struct console *con, struct nbcon_state *state)
{
state->atom = atomic_read(&ACCESS_PRIVATE(con, nbcon_state));
}
/**
* nbcon_state_try_cmpxchg() - Helper function for atomic_try_cmpxchg() on console state
* @con: Console to update
* @cur: Old/expected state
* @new: New state
*
* Return: True on success. False on fail and @cur is updated.
*/
static inline bool nbcon_state_try_cmpxchg(struct console *con, struct nbcon_state *cur,
struct nbcon_state *new)
{
return atomic_try_cmpxchg(&ACCESS_PRIVATE(con, nbcon_state), &cur->atom, new->atom);
}
/**
* nbcon_init - Initialize the nbcon console specific data
* @con: Console to initialize
*/
void nbcon_init(struct console *con)
{
struct nbcon_state state = { };
nbcon_state_set(con, &state);
}
/**
* nbcon_cleanup - Cleanup the nbcon console specific data
* @con: Console to cleanup
*/
void nbcon_cleanup(struct console *con)
{
struct nbcon_state state = { };
nbcon_state_set(con, &state);
}
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