[mirror_ubuntu-jammy-kernel.git] / include / linux / serial_core.h

/* SPDX-License-Identifier: GPL-2.0-or-later */
/*
 *  linux/drivers/char/serial_core.h
 *
 *  Copyright (C) 2000 Deep Blue Solutions Ltd.
 */
#ifndef LINUX_SERIAL_CORE_H
#define LINUX_SERIAL_CORE_H

#include <linux/bitops.h>
#include <linux/compiler.h>
#include <linux/console.h>
#include <linux/interrupt.h>
#include <linux/circ_buf.h>
#include <linux/spinlock.h>
#include <linux/sched.h>
#include <linux/tty.h>
#include <linux/mutex.h>
#include <linux/sysrq.h>
#include <uapi/linux/serial_core.h>

#ifdef CONFIG_SERIAL_CORE_CONSOLE
#define uart_console(port) \
	((port)->cons && (port)->cons->index == (port)->line)
#else
#define uart_console(port)      ({ (void)port; 0; })
#endif

struct uart_port;
struct serial_struct;
struct device;

/*
 * This structure describes all the operations that can be done on the
 * physical hardware.  See Documentation/driver-api/serial/driver.rst for details.
 */
struct uart_ops {
	unsigned int	(*tx_empty)(struct uart_port *);
	void		(*set_mctrl)(struct uart_port *, unsigned int mctrl);
	unsigned int	(*get_mctrl)(struct uart_port *);
	void		(*stop_tx)(struct uart_port *);
	void		(*start_tx)(struct uart_port *);
	void		(*throttle)(struct uart_port *);
	void		(*unthrottle)(struct uart_port *);
	void		(*send_xchar)(struct uart_port *, char ch);
	void		(*stop_rx)(struct uart_port *);
	void		(*enable_ms)(struct uart_port *);
	void		(*break_ctl)(struct uart_port *, int ctl);
	int		(*startup)(struct uart_port *);
	void		(*shutdown)(struct uart_port *);
	void		(*flush_buffer)(struct uart_port *);
	void		(*set_termios)(struct uart_port *, struct ktermios *new,
				       struct ktermios *old);
	void		(*set_ldisc)(struct uart_port *, struct ktermios *);
	void		(*pm)(struct uart_port *, unsigned int state,
			      unsigned int oldstate);

	/*
	 * Return a string describing the type of the port
	 */
	const char	*(*type)(struct uart_port *);

	/*
	 * Release IO and memory resources used by the port.
	 * This includes iounmap if necessary.
	 */
	void		(*release_port)(struct uart_port *);

	/*
	 * Request IO and memory resources used by the port.
	 * This includes iomapping the port if necessary.
	 */
	int		(*request_port)(struct uart_port *);
	void		(*config_port)(struct uart_port *, int);
	int		(*verify_port)(struct uart_port *, struct serial_struct *);
	int		(*ioctl)(struct uart_port *, unsigned int, unsigned long);
#ifdef CONFIG_CONSOLE_POLL
	int		(*poll_init)(struct uart_port *);
	void		(*poll_put_char)(struct uart_port *, unsigned char);
	int		(*poll_get_char)(struct uart_port *);
#endif
};

#define NO_POLL_CHAR		0x00ff0000
#define UART_CONFIG_TYPE	(1 << 0)
#define UART_CONFIG_IRQ		(1 << 1)

struct uart_icount {
	__u32	cts;
	__u32	dsr;
	__u32	rng;
	__u32	dcd;
	__u32	rx;
	__u32	tx;
	__u32	frame;
	__u32	overrun;
	__u32	parity;
	__u32	brk;
	__u32	buf_overrun;
};

typedef unsigned int __bitwise upf_t;
typedef unsigned int __bitwise upstat_t;

struct uart_port {
	spinlock_t		lock;			/* port lock */
	unsigned long		iobase;			/* in/out[bwl] */
	unsigned char __iomem	*membase;		/* read/write[bwl] */
	unsigned int		(*serial_in)(struct uart_port *, int);
	void			(*serial_out)(struct uart_port *, int, int);
	void			(*set_termios)(struct uart_port *,
				               struct ktermios *new,
				               struct ktermios *old);
	void			(*set_ldisc)(struct uart_port *,
					     struct ktermios *);
	unsigned int		(*get_mctrl)(struct uart_port *);
	void			(*set_mctrl)(struct uart_port *, unsigned int);
	unsigned int		(*get_divisor)(struct uart_port *,
					       unsigned int baud,
					       unsigned int *frac);
	void			(*set_divisor)(struct uart_port *,
					       unsigned int baud,
					       unsigned int quot,
					       unsigned int quot_frac);
	int			(*startup)(struct uart_port *port);
	void			(*shutdown)(struct uart_port *port);
	void			(*throttle)(struct uart_port *port);
	void			(*unthrottle)(struct uart_port *port);
	int			(*handle_irq)(struct uart_port *);
	void			(*pm)(struct uart_port *, unsigned int state,
				      unsigned int old);
	void			(*handle_break)(struct uart_port *);
	int			(*rs485_config)(struct uart_port *,
						struct serial_rs485 *rs485);
	int			(*iso7816_config)(struct uart_port *,
						  struct serial_iso7816 *iso7816);
	unsigned int		irq;			/* irq number */
	unsigned long		irqflags;		/* irq flags  */
	unsigned int		uartclk;		/* base uart clock */
	unsigned int		fifosize;		/* tx fifo size */
	unsigned char		x_char;			/* xon/xoff char */
	unsigned char		regshift;		/* reg offset shift */
	unsigned char		iotype;			/* io access style */
	unsigned char		quirks;			/* internal quirks */

#define UPIO_PORT		(SERIAL_IO_PORT)	/* 8b I/O port access */
#define UPIO_HUB6		(SERIAL_IO_HUB6)	/* Hub6 ISA card */
#define UPIO_MEM		(SERIAL_IO_MEM)		/* driver-specific */
#define UPIO_MEM32		(SERIAL_IO_MEM32)	/* 32b little endian */
#define UPIO_AU			(SERIAL_IO_AU)		/* Au1x00 and RT288x type IO */
#define UPIO_TSI		(SERIAL_IO_TSI)		/* Tsi108/109 type IO */
#define UPIO_MEM32BE		(SERIAL_IO_MEM32BE)	/* 32b big endian */
#define UPIO_MEM16		(SERIAL_IO_MEM16)	/* 16b little endian */

	/* quirks must be updated while holding port mutex */
#define UPQ_NO_TXEN_TEST	BIT(0)

	unsigned int		read_status_mask;	/* driver specific */
	unsigned int		ignore_status_mask;	/* driver specific */
	struct uart_state	*state;			/* pointer to parent state */
	struct uart_icount	icount;			/* statistics */

	struct console		*cons;			/* struct console, if any */
#if defined(CONFIG_SERIAL_CORE_CONSOLE) || defined(SUPPORT_SYSRQ)
	unsigned long		sysrq;			/* sysrq timeout */
	unsigned int		sysrq_ch;		/* char for sysrq */
#endif

	/* flags must be updated while holding port mutex */
	upf_t			flags;

	/*
	 * These flags must be equivalent to the flags defined in
	 * include/uapi/linux/tty_flags.h which are the userspace definitions
	 * assigned from the serial_struct flags in uart_set_info()
	 * [for bit definitions in the UPF_CHANGE_MASK]
	 *
	 * Bits [0..UPF_LAST_USER] are userspace defined/visible/changeable
	 * The remaining bits are serial-core specific and not modifiable by
	 * userspace.
	 */
#define UPF_FOURPORT		((__force upf_t) ASYNC_FOURPORT       /* 1  */ )
#define UPF_SAK			((__force upf_t) ASYNC_SAK            /* 2  */ )
#define UPF_SPD_HI		((__force upf_t) ASYNC_SPD_HI         /* 4  */ )
#define UPF_SPD_VHI		((__force upf_t) ASYNC_SPD_VHI        /* 5  */ )
#define UPF_SPD_CUST		((__force upf_t) ASYNC_SPD_CUST   /* 0x0030 */ )
#define UPF_SPD_WARP		((__force upf_t) ASYNC_SPD_WARP   /* 0x1010 */ )
#define UPF_SPD_MASK		((__force upf_t) ASYNC_SPD_MASK   /* 0x1030 */ )
#define UPF_SKIP_TEST		((__force upf_t) ASYNC_SKIP_TEST      /* 6  */ )
#define UPF_AUTO_IRQ		((__force upf_t) ASYNC_AUTO_IRQ       /* 7  */ )
#define UPF_HARDPPS_CD		((__force upf_t) ASYNC_HARDPPS_CD     /* 11 */ )
#define UPF_SPD_SHI		((__force upf_t) ASYNC_SPD_SHI        /* 12 */ )
#define UPF_LOW_LATENCY		((__force upf_t) ASYNC_LOW_LATENCY    /* 13 */ )
#define UPF_BUGGY_UART		((__force upf_t) ASYNC_BUGGY_UART     /* 14 */ )
#define UPF_MAGIC_MULTIPLIER	((__force upf_t) ASYNC_MAGIC_MULTIPLIER /* 16 */ )

#define UPF_NO_THRE_TEST	((__force upf_t) (1 << 19))
/* Port has hardware-assisted h/w flow control */
#define UPF_AUTO_CTS		((__force upf_t) (1 << 20))
#define UPF_AUTO_RTS		((__force upf_t) (1 << 21))
#define UPF_HARD_FLOW		((__force upf_t) (UPF_AUTO_CTS | UPF_AUTO_RTS))
/* Port has hardware-assisted s/w flow control */
#define UPF_SOFT_FLOW		((__force upf_t) (1 << 22))
#define UPF_CONS_FLOW		((__force upf_t) (1 << 23))
#define UPF_SHARE_IRQ		((__force upf_t) (1 << 24))
#define UPF_EXAR_EFR		((__force upf_t) (1 << 25))
#define UPF_BUG_THRE		((__force upf_t) (1 << 26))
/* The exact UART type is known and should not be probed.  */
#define UPF_FIXED_TYPE		((__force upf_t) (1 << 27))
#define UPF_BOOT_AUTOCONF	((__force upf_t) (1 << 28))
#define UPF_FIXED_PORT		((__force upf_t) (1 << 29))
#define UPF_DEAD		((__force upf_t) (1 << 30))
#define UPF_IOREMAP		((__force upf_t) (1 << 31))

#define __UPF_CHANGE_MASK	0x17fff
#define UPF_CHANGE_MASK		((__force upf_t) __UPF_CHANGE_MASK)
#define UPF_USR_MASK		((__force upf_t) (UPF_SPD_MASK|UPF_LOW_LATENCY))

#if __UPF_CHANGE_MASK > ASYNC_FLAGS
#error Change mask not equivalent to userspace-visible bit defines
#endif

	/*
	 * Must hold termios_rwsem, port mutex and port lock to change;
	 * can hold any one lock to read.
	 */
	upstat_t		status;

#define UPSTAT_CTS_ENABLE	((__force upstat_t) (1 << 0))
#define UPSTAT_DCD_ENABLE	((__force upstat_t) (1 << 1))
#define UPSTAT_AUTORTS		((__force upstat_t) (1 << 2))
#define UPSTAT_AUTOCTS		((__force upstat_t) (1 << 3))
#define UPSTAT_AUTOXOFF		((__force upstat_t) (1 << 4))
#define UPSTAT_SYNC_FIFO	((__force upstat_t) (1 << 5))

	int			hw_stopped;		/* sw-assisted CTS flow state */
	unsigned int		mctrl;			/* current modem ctrl settings */
	unsigned int		timeout;		/* character-based timeout */
	unsigned int		type;			/* port type */
	const struct uart_ops	*ops;
	unsigned int		custom_divisor;
	unsigned int		line;			/* port index */
	unsigned int		minor;
	resource_size_t		mapbase;		/* for ioremap */
	resource_size_t		mapsize;
	struct device		*dev;			/* parent device */
	unsigned char		hub6;			/* this should be in the 8250 driver */
	unsigned char		suspended;
	unsigned char		unused[2];
	const char		*name;			/* port name */
	struct attribute_group	*attr_group;		/* port specific attributes */
	const struct attribute_group **tty_groups;	/* all attributes (serial core use only) */
	struct serial_rs485     rs485;
	struct serial_iso7816   iso7816;
	void			*private_data;		/* generic platform data pointer */
};

static inline int serial_port_in(struct uart_port *up, int offset)
{
	return up->serial_in(up, offset);
}

static inline void serial_port_out(struct uart_port *up, int offset, int value)
{
	up->serial_out(up, offset, value);
}

/**
 * enum uart_pm_state - power states for UARTs
 * @UART_PM_STATE_ON: UART is powered, up and operational
 * @UART_PM_STATE_OFF: UART is powered off
 * @UART_PM_STATE_UNDEFINED: sentinel
 */
enum uart_pm_state {
	UART_PM_STATE_ON = 0,
	UART_PM_STATE_OFF = 3, /* number taken from ACPI */
	UART_PM_STATE_UNDEFINED,
};

/*
 * This is the state information which is persistent across opens.
 */
struct uart_state {
	struct tty_port		port;

	enum uart_pm_state	pm_state;
	struct circ_buf		xmit;

	atomic_t		refcount;
	wait_queue_head_t	remove_wait;
	struct uart_port	*uart_port;
};

#define UART_XMIT_SIZE	PAGE_SIZE


/* number of characters left in xmit buffer before we ask for more */
#define WAKEUP_CHARS		256

struct module;
struct tty_driver;

struct uart_driver {
	struct module		*owner;
	const char		*driver_name;
	const char		*dev_name;
	int			 major;
	int			 minor;
	int			 nr;
	struct console		*cons;

	/*
	 * these are private; the low level driver should not
	 * touch these; they should be initialised to NULL
	 */
	struct uart_state	*state;
	struct tty_driver	*tty_driver;
};

void uart_write_wakeup(struct uart_port *port);

/*
 * Baud rate helpers.
 */
void uart_update_timeout(struct uart_port *port, unsigned int cflag,
			 unsigned int baud);
unsigned int uart_get_baud_rate(struct uart_port *port, struct ktermios *termios,
				struct ktermios *old, unsigned int min,
				unsigned int max);
unsigned int uart_get_divisor(struct uart_port *port, unsigned int baud);

/* Base timer interval for polling */
static inline int uart_poll_timeout(struct uart_port *port)
{
	int timeout = port->timeout;

	return timeout > 6 ? (timeout / 2 - 2) : 1;
}

/*
 * Console helpers.
 */
struct earlycon_device {
	struct console *con;
	struct uart_port port;
	char options[16];		/* e.g., 115200n8 */
	unsigned int baud;
};

struct earlycon_id {
	char	name[15];
	char	name_term;	/* In case compiler didn't '\0' term name */
	char	compatible[128];
	int	(*setup)(struct earlycon_device *, const char *options);
};

extern const struct earlycon_id *__earlycon_table[];
extern const struct earlycon_id *__earlycon_table_end[];

#if defined(CONFIG_SERIAL_EARLYCON) && !defined(MODULE)
#define EARLYCON_USED_OR_UNUSED	__used
#else
#define EARLYCON_USED_OR_UNUSED	__maybe_unused
#endif

#define _OF_EARLYCON_DECLARE(_name, compat, fn, unique_id)		\
	static const struct earlycon_id unique_id			\
	     EARLYCON_USED_OR_UNUSED __initconst			\
		= { .name = __stringify(_name),				\
		    .compatible = compat,				\
		    .setup = fn  };					\
	static const struct earlycon_id EARLYCON_USED_OR_UNUSED		\
		__section(__earlycon_table)				\
		* const __PASTE(__p, unique_id) = &unique_id

#define OF_EARLYCON_DECLARE(_name, compat, fn)				\
	_OF_EARLYCON_DECLARE(_name, compat, fn,				\
			     __UNIQUE_ID(__earlycon_##_name))

#define EARLYCON_DECLARE(_name, fn)	OF_EARLYCON_DECLARE(_name, "", fn)

extern int of_setup_earlycon(const struct earlycon_id *match,
			     unsigned long node,
			     const char *options);

#ifdef CONFIG_SERIAL_EARLYCON
extern bool earlycon_acpi_spcr_enable __initdata;
int setup_earlycon(char *buf);
#else
static const bool earlycon_acpi_spcr_enable EARLYCON_USED_OR_UNUSED;
static inline int setup_earlycon(char *buf) { return 0; }
#endif

struct uart_port *uart_get_console(struct uart_port *ports, int nr,
				   struct console *c);
int uart_parse_earlycon(char *p, unsigned char *iotype, resource_size_t *addr,
			char **options);
void uart_parse_options(const char *options, int *baud, int *parity, int *bits,
			int *flow);
int uart_set_options(struct uart_port *port, struct console *co, int baud,
		     int parity, int bits, int flow);
struct tty_driver *uart_console_device(struct console *co, int *index);
void uart_console_write(struct uart_port *port, const char *s,
			unsigned int count,
			void (*putchar)(struct uart_port *, int));

/*
 * Port/driver registration/removal
 */
int uart_register_driver(struct uart_driver *uart);
void uart_unregister_driver(struct uart_driver *uart);
int uart_add_one_port(struct uart_driver *reg, struct uart_port *port);
int uart_remove_one_port(struct uart_driver *reg, struct uart_port *port);
int uart_match_port(struct uart_port *port1, struct uart_port *port2);

/*
 * Power Management
 */
int uart_suspend_port(struct uart_driver *reg, struct uart_port *port);
int uart_resume_port(struct uart_driver *reg, struct uart_port *port);

#define uart_circ_empty(circ)		((circ)->head == (circ)->tail)
#define uart_circ_clear(circ)		((circ)->head = (circ)->tail = 0)

#define uart_circ_chars_pending(circ)	\
	(CIRC_CNT((circ)->head, (circ)->tail, UART_XMIT_SIZE))

#define uart_circ_chars_free(circ)	\
	(CIRC_SPACE((circ)->head, (circ)->tail, UART_XMIT_SIZE))

static inline int uart_tx_stopped(struct uart_port *port)
{
	struct tty_struct *tty = port->state->port.tty;
	if ((tty && tty->stopped) || port->hw_stopped)
		return 1;
	return 0;
}

static inline bool uart_cts_enabled(struct uart_port *uport)
{
	return !!(uport->status & UPSTAT_CTS_ENABLE);
}

static inline bool uart_softcts_mode(struct uart_port *uport)
{
	upstat_t mask = UPSTAT_CTS_ENABLE | UPSTAT_AUTOCTS;

	return ((uport->status & mask) == UPSTAT_CTS_ENABLE);
}

/*
 * The following are helper functions for the low level drivers.
 */

extern void uart_handle_dcd_change(struct uart_port *uport,
		unsigned int status);
extern void uart_handle_cts_change(struct uart_port *uport,
		unsigned int status);

extern void uart_insert_char(struct uart_port *port, unsigned int status,
		 unsigned int overrun, unsigned int ch, unsigned int flag);

#if defined(SUPPORT_SYSRQ) && defined(CONFIG_MAGIC_SYSRQ_SERIAL)
static inline int
uart_handle_sysrq_char(struct uart_port *port, unsigned int ch)
{
	if (port->sysrq) {
		if (ch && time_before(jiffies, port->sysrq)) {
			handle_sysrq(ch);
			port->sysrq = 0;
			return 1;
		}
		port->sysrq = 0;
	}
	return 0;
}
static inline int
uart_prepare_sysrq_char(struct uart_port *port, unsigned int ch)
{
	if (port->sysrq) {
		if (ch && time_before(jiffies, port->sysrq)) {
			port->sysrq_ch = ch;
			port->sysrq = 0;
			return 1;
		}
		port->sysrq = 0;
	}
	return 0;
}
static inline void
uart_unlock_and_check_sysrq(struct uart_port *port, unsigned long irqflags)
{
	int sysrq_ch;

	sysrq_ch = port->sysrq_ch;
	port->sysrq_ch = 0;

	spin_unlock_irqrestore(&port->lock, irqflags);

	if (sysrq_ch)
		handle_sysrq(sysrq_ch);
}
#else
static inline int
uart_handle_sysrq_char(struct uart_port *port, unsigned int ch) { return 0; }
static inline int
uart_prepare_sysrq_char(struct uart_port *port, unsigned int ch) { return 0; }
static inline void
uart_unlock_and_check_sysrq(struct uart_port *port, unsigned long irqflags)
{
	spin_unlock_irqrestore(&port->lock, irqflags);
}
#endif

/*
 * We do the SysRQ and SAK checking like this...
 */
static inline int uart_handle_break(struct uart_port *port)
{
	struct uart_state *state = port->state;

	if (port->handle_break)
		port->handle_break(port);

#ifdef SUPPORT_SYSRQ
	if (port->cons && port->cons->index == port->line) {
		if (!port->sysrq) {
			port->sysrq = jiffies + HZ*5;
			return 1;
		}
		port->sysrq = 0;
	}
#endif
	if (port->flags & UPF_SAK)
		do_SAK(state->port.tty);
	return 0;
}

/*
 *	UART_ENABLE_MS - determine if port should enable modem status irqs
 */
#define UART_ENABLE_MS(port,cflag)	((port)->flags & UPF_HARDPPS_CD || \
					 (cflag) & CRTSCTS || \
					 !((cflag) & CLOCAL))

void uart_get_rs485_mode(struct device *dev, struct serial_rs485 *rs485conf);
#endif /* LINUX_SERIAL_CORE_H */
Commit	Line	Data
1a59d1b8	1	/* SPDX-License-Identifier: GPL-2.0-or-later */
1da177e4 LT	2	/*
	3	* linux/drivers/char/serial_core.h
	4	*
	5	* Copyright (C) 2000 Deep Blue Solutions Ltd.
1da177e4 LT	6	*/
	7	#ifndef LINUX_SERIAL_CORE_H
	8	#define LINUX_SERIAL_CORE_H
	9
c7ac15ce	10	#include <linux/bitops.h>
661f83a6	11	#include <linux/compiler.h>
3e6f8806	12	#include <linux/console.h>
1da177e4 LT	13	#include <linux/interrupt.h>
	14	#include <linux/circ_buf.h>
	15	#include <linux/spinlock.h>
	16	#include <linux/sched.h>
	17	#include <linux/tty.h>
e2862f6a	18	#include <linux/mutex.h>
b11115c1	19	#include <linux/sysrq.h>
607ca46e	20	#include <uapi/linux/serial_core.h>
1da177e4	21
cf0ebee0 SP	22	#ifdef CONFIG_SERIAL_CORE_CONSOLE
	23	#define uart_console(port) \
	24	((port)->cons && (port)->cons->index == (port)->line)
	25	#else
6b3cddcc	26	#define uart_console(port) ({ (void)port; 0; })
cf0ebee0 SP	27	#endif
cf0ebee0 SP	28
1da177e4	29	struct uart_port;
1da177e4 LT	30	struct serial_struct;
	31	struct device;
	32
	33	/*
e759d7c5	34	* This structure describes all the operations that can be done on the
65388dad	35	* physical hardware. See Documentation/driver-api/serial/driver.rst for details.
1da177e4 LT	36	*/
	37	struct uart_ops {
	38	unsigned int (tx_empty)(struct uart_port );
	39	void (set_mctrl)(struct uart_port , unsigned int mctrl);
	40	unsigned int (get_mctrl)(struct uart_port );
b129a8cc RK	41	void (stop_tx)(struct uart_port );
b129a8cc RK	42	void (start_tx)(struct uart_port );
9aba8d5b RK	43	void (throttle)(struct uart_port );
9aba8d5b RK	44	void (unthrottle)(struct uart_port );
1da177e4 LT	45	void (send_xchar)(struct uart_port , char ch);
	46	void (stop_rx)(struct uart_port );
	47	void (enable_ms)(struct uart_port );
	48	void (break_ctl)(struct uart_port , int ctl);
	49	int (startup)(struct uart_port );
	50	void (shutdown)(struct uart_port );
6bb0e3a5	51	void (flush_buffer)(struct uart_port );
606d099c AC	52	void (set_termios)(struct uart_port , struct ktermios *new,
606d099c AC	53	struct ktermios *old);
732a84a0	54	void (set_ldisc)(struct uart_port , struct ktermios *);
1da177e4 LT	55	void (pm)(struct uart_port , unsigned int state,
1da177e4 LT	56	unsigned int oldstate);
1da177e4 LT	57
	58	/*
	59	* Return a string describing the type of the port
	60	*/
e759d7c5	61	const char (type)(struct uart_port *);
1da177e4 LT	62
	63	/*
	64	* Release IO and memory resources used by the port.
	65	* This includes iounmap if necessary.
	66	*/
	67	void (release_port)(struct uart_port );
	68
	69	/*
	70	* Request IO and memory resources used by the port.
	71	* This includes iomapping the port if necessary.
	72	*/
	73	int (request_port)(struct uart_port );
	74	void (config_port)(struct uart_port , int);
	75	int (verify_port)(struct uart_port , struct serial_struct *);
	76	int (ioctl)(struct uart_port , unsigned int, unsigned long);
f2d937f3	77	#ifdef CONFIG_CONSOLE_POLL
c7f3e708	78	int (poll_init)(struct uart_port );
e759d7c5	79	void (poll_put_char)(struct uart_port , unsigned char);
f2d937f3 JW	80	int (poll_get_char)(struct uart_port );
f2d937f3 JW	81	#endif
1da177e4 LT	82	};
1da177e4 LT	83
f5316b4a	84	#define NO_POLL_CHAR 0x00ff0000
1da177e4 LT	85	#define UART_CONFIG_TYPE (1 << 0)
	86	#define UART_CONFIG_IRQ (1 << 1)
	87
	88	struct uart_icount {
	89	__u32 cts;
	90	__u32 dsr;
	91	__u32 rng;
	92	__u32 dcd;
	93	__u32 rx;
	94	__u32 tx;
	95	__u32 frame;
	96	__u32 overrun;
	97	__u32 parity;
	98	__u32 brk;
	99	__u32 buf_overrun;
	100	};
	101
9efeccac MT	102	typedef unsigned int __bitwise upf_t;
9efeccac MT	103	typedef unsigned int __bitwise upstat_t;
0077d45e	104
1da177e4 LT	105	struct uart_port {
1da177e4 LT	106	spinlock_t lock; /* port lock */
0c8946d9	107	unsigned long iobase; /* in/out[bwl] */
1da177e4	108	unsigned char __iomem membase; / read/write[bwl] */
7d6a07d1 DD	109	unsigned int (serial_in)(struct uart_port , int);
7d6a07d1 DD	110	void (serial_out)(struct uart_port , int, int);
235dae5d PL	111	void (set_termios)(struct uart_port ,
	112	struct ktermios *new,
	113	struct ktermios *old);
db405a8f EB	114	void (set_ldisc)(struct uart_port ,
db405a8f EB	115	struct ktermios *);
144ef5c2	116	unsigned int (get_mctrl)(struct uart_port );
4bf4ea9d	117	void (set_mctrl)(struct uart_port , unsigned int);
0238d2b4 JZ	118	unsigned int (get_divisor)(struct uart_port ,
	119	unsigned int baud,
	120	unsigned int *frac);
	121	void (set_divisor)(struct uart_port ,
	122	unsigned int baud,
	123	unsigned int quot,
	124	unsigned int quot_frac);
b99b121b SAS	125	int (startup)(struct uart_port port);
b99b121b SAS	126	void (shutdown)(struct uart_port port);
234abab1 SAS	127	void (throttle)(struct uart_port port);
234abab1 SAS	128	void (unthrottle)(struct uart_port port);
a74036f5	129	int (handle_irq)(struct uart_port );
c161afe9 ML	130	void (pm)(struct uart_port , unsigned int state,
c161afe9 ML	131	unsigned int old);
bf03f65b	132	void (handle_break)(struct uart_port );
a5f276f1 RR	133	int (rs485_config)(struct uart_port ,
a5f276f1 RR	134	struct serial_rs485 *rs485);
ad8c0eaa NF	135	int (iso7816_config)(struct uart_port ,
ad8c0eaa NF	136	struct serial_iso7816 *iso7816);
1da177e4	137	unsigned int irq; /* irq number */
1c2f0493	138	unsigned long irqflags; /* irq flags */
1da177e4	139	unsigned int uartclk; /* base uart clock */
947deee8	140	unsigned int fifosize; /* tx fifo size */
1da177e4 LT	141	unsigned char x_char; /* xon/xoff char */
	142	unsigned char regshift; /* reg offset shift */
	143	unsigned char iotype; /* io access style */
c7ac15ce	144	unsigned char quirks; /* internal quirks */
1da177e4	145
647f162b PH	146	#define UPIO_PORT (SERIAL_IO_PORT) /* 8b I/O port access */
647f162b PH	147	#define UPIO_HUB6 (SERIAL_IO_HUB6) /* Hub6 ISA card */
858965d9	148	#define UPIO_MEM (SERIAL_IO_MEM) /* driver-specific */
647f162b PH	149	#define UPIO_MEM32 (SERIAL_IO_MEM32) /* 32b little endian */
	150	#define UPIO_AU (SERIAL_IO_AU) /* Au1x00 and RT288x type IO */
	151	#define UPIO_TSI (SERIAL_IO_TSI) /* Tsi108/109 type IO */
	152	#define UPIO_MEM32BE (SERIAL_IO_MEM32BE) /* 32b big endian */
bd94c407	153	#define UPIO_MEM16 (SERIAL_IO_MEM16) /* 16b little endian */
1da177e4	154
c7ac15ce AS	155	/* quirks must be updated while holding port mutex */
	156	#define UPQ_NO_TXEN_TEST BIT(0)
	157
1da177e4 LT	158	unsigned int read_status_mask; /* driver specific */
1da177e4 LT	159	unsigned int ignore_status_mask; /* driver specific */
ebd2c8f6	160	struct uart_state state; / pointer to parent state */
1da177e4 LT	161	struct uart_icount icount; /* statistics */
	162
	163	struct console cons; / struct console, if any */
06e82df0	164	#if defined(CONFIG_SERIAL_CORE_CONSOLE) \|\| defined(SUPPORT_SYSRQ)
1da177e4	165	unsigned long sysrq; /* sysrq timeout */
d6e19358	166	unsigned int sysrq_ch; /* char for sysrq */
1da177e4 LT	167	#endif
1da177e4 LT	168
8a949b07	169	/* flags must be updated while holding port mutex */
0077d45e RK	170	upf_t flags;
0077d45e RK	171
904326ec PH	172	/*
	173	* These flags must be equivalent to the flags defined in
	174	* include/uapi/linux/tty_flags.h which are the userspace definitions
	175	* assigned from the serial_struct flags in uart_set_info()
	176	* [for bit definitions in the UPF_CHANGE_MASK]
	177	*
	178	* Bits [0..UPF_LAST_USER] are userspace defined/visible/changeable
904326ec PH	179	* The remaining bits are serial-core specific and not modifiable by
	180	* userspace.
	181	*/
	182	#define UPF_FOURPORT ((__force upf_t) ASYNC_FOURPORT /* 1 */ )
	183	#define UPF_SAK ((__force upf_t) ASYNC_SAK /* 2 */ )
	184	#define UPF_SPD_HI ((__force upf_t) ASYNC_SPD_HI /* 4 */ )
	185	#define UPF_SPD_VHI ((__force upf_t) ASYNC_SPD_VHI /* 5 */ )
	186	#define UPF_SPD_CUST ((__force upf_t) ASYNC_SPD_CUST /* 0x0030 */ )
	187	#define UPF_SPD_WARP ((__force upf_t) ASYNC_SPD_WARP /* 0x1010 */ )
	188	#define UPF_SPD_MASK ((__force upf_t) ASYNC_SPD_MASK /* 0x1030 */ )
	189	#define UPF_SKIP_TEST ((__force upf_t) ASYNC_SKIP_TEST /* 6 */ )
	190	#define UPF_AUTO_IRQ ((__force upf_t) ASYNC_AUTO_IRQ /* 7 */ )
	191	#define UPF_HARDPPS_CD ((__force upf_t) ASYNC_HARDPPS_CD /* 11 */ )
	192	#define UPF_SPD_SHI ((__force upf_t) ASYNC_SPD_SHI /* 12 */ )
	193	#define UPF_LOW_LATENCY ((__force upf_t) ASYNC_LOW_LATENCY /* 13 */ )
	194	#define UPF_BUGGY_UART ((__force upf_t) ASYNC_BUGGY_UART /* 14 */ )
904326ec PH	195	#define UPF_MAGIC_MULTIPLIER ((__force upf_t) ASYNC_MAGIC_MULTIPLIER /* 16 */ )
904326ec PH	196
ea5244e2	197	#define UPF_NO_THRE_TEST ((__force upf_t) (1 << 19))
391f93f2 PH	198	/* Port has hardware-assisted h/w flow control */
	199	#define UPF_AUTO_CTS ((__force upf_t) (1 << 20))
	200	#define UPF_AUTO_RTS ((__force upf_t) (1 << 21))
	201	#define UPF_HARD_FLOW ((__force upf_t) (UPF_AUTO_CTS \| UPF_AUTO_RTS))
2cbacafd RK	202	/* Port has hardware-assisted s/w flow control */
2cbacafd RK	203	#define UPF_SOFT_FLOW ((__force upf_t) (1 << 22))
0077d45e RK	204	#define UPF_CONS_FLOW ((__force upf_t) (1 << 23))
0077d45e RK	205	#define UPF_SHARE_IRQ ((__force upf_t) (1 << 24))
06315348	206	#define UPF_EXAR_EFR ((__force upf_t) (1 << 25))
bc02d15a	207	#define UPF_BUG_THRE ((__force upf_t) (1 << 26))
8e23fcc8 DD	208	/* The exact UART type is known and should not be probed. */
8e23fcc8 DD	209	#define UPF_FIXED_TYPE ((__force upf_t) (1 << 27))
0077d45e	210	#define UPF_BOOT_AUTOCONF ((__force upf_t) (1 << 28))
abb4a239	211	#define UPF_FIXED_PORT ((__force upf_t) (1 << 29))
68ac64cd	212	#define UPF_DEAD ((__force upf_t) (1 << 30))
0077d45e RK	213	#define UPF_IOREMAP ((__force upf_t) (1 << 31))
0077d45e RK	214
904326ec PH	215	#define __UPF_CHANGE_MASK 0x17fff
904326ec PH	216	#define UPF_CHANGE_MASK ((__force upf_t) __UPF_CHANGE_MASK)
0077d45e	217	#define UPF_USR_MASK ((__force upf_t) (UPF_SPD_MASK\|UPF_LOW_LATENCY))
1da177e4	218
904326ec PH	219	#if __UPF_CHANGE_MASK > ASYNC_FLAGS
	220	#error Change mask not equivalent to userspace-visible bit defines
	221	#endif
	222
391f93f2 PH	223	/*
	224	* Must hold termios_rwsem, port mutex and port lock to change;
	225	* can hold any one lock to read.
	226	*/
299245a1 PH	227	upstat_t status;
	228
	229	#define UPSTAT_CTS_ENABLE ((__force upstat_t) (1 << 0))
	230	#define UPSTAT_DCD_ENABLE ((__force upstat_t) (1 << 1))
391f93f2 PH	231	#define UPSTAT_AUTORTS ((__force upstat_t) (1 << 2))
	232	#define UPSTAT_AUTOCTS ((__force upstat_t) (1 << 3))
	233	#define UPSTAT_AUTOXOFF ((__force upstat_t) (1 << 4))
c5f78b1f	234	#define UPSTAT_SYNC_FIFO ((__force upstat_t) (1 << 5))
299245a1	235
d01f4d18	236	int hw_stopped; /* sw-assisted CTS flow state */
1da177e4 LT	237	unsigned int mctrl; /* current modem ctrl settings */
	238	unsigned int timeout; /* character-based timeout */
	239	unsigned int type; /* port type */
ba899dbc	240	const struct uart_ops *ops;
1da177e4 LT	241	unsigned int custom_divisor;
1da177e4 LT	242	unsigned int line; /* port index */
959801fe	243	unsigned int minor;
4f640efb	244	resource_size_t mapbase; /* for ioremap */
ee97d0e3	245	resource_size_t mapsize;
1da177e4 LT	246	struct device dev; / parent device */
1da177e4 LT	247	unsigned char hub6; /* this should be in the 8250 driver */
b3b708fa	248	unsigned char suspended;
817e9bc8	249	unsigned char unused[2];
2e94d5ae	250	const char name; / port name */
266dcff0 GKH	251	struct attribute_group attr_group; / port specific attributes */
266dcff0 GKH	252	const struct attribute_group *tty_groups; / all attributes (serial core use only) */
a5f276f1	253	struct serial_rs485 rs485;
ad8c0eaa	254	struct serial_iso7816 iso7816;
beab697a	255	void private_data; / generic platform data pointer */
1da177e4 LT	256	};
1da177e4 LT	257
927353a7 PG	258	static inline int serial_port_in(struct uart_port *up, int offset)
	259	{
	260	return up->serial_in(up, offset);
	261	}
	262
	263	static inline void serial_port_out(struct uart_port *up, int offset, int value)
	264	{
	265	up->serial_out(up, offset, value);
	266	}
	267
6f538fe3 LW	268	/**
	269	* enum uart_pm_state - power states for UARTs
	270	* @UART_PM_STATE_ON: UART is powered, up and operational
	271	* @UART_PM_STATE_OFF: UART is powered off
	272	* @UART_PM_STATE_UNDEFINED: sentinel
	273	*/
	274	enum uart_pm_state {
	275	UART_PM_STATE_ON = 0,
	276	UART_PM_STATE_OFF = 3, /* number taken from ACPI */
	277	UART_PM_STATE_UNDEFINED,
	278	};
	279
ebd2c8f6 AC	280	/*
ebd2c8f6 AC	281	* This is the state information which is persistent across opens.
ebd2c8f6 AC	282	*/
ebd2c8f6 AC	283	struct uart_state {
df4f4dd4	284	struct tty_port port;
ebd2c8f6	285
6f538fe3	286	enum uart_pm_state pm_state;
1da177e4	287	struct circ_buf xmit;
1da177e4	288
9ed19428 PH	289	atomic_t refcount;
9ed19428 PH	290	wait_queue_head_t remove_wait;
ebd2c8f6	291	struct uart_port *uart_port;
f751928e AC	292	};
	293
	294	#define UART_XMIT_SIZE PAGE_SIZE
	295
	296
1da177e4 LT	297	/* number of characters left in xmit buffer before we ask for more */
	298	#define WAKEUP_CHARS 256
	299
	300	struct module;
	301	struct tty_driver;
	302
	303	struct uart_driver {
	304	struct module *owner;
	305	const char *driver_name;
	306	const char *dev_name;
1da177e4 LT	307	int major;
	308	int minor;
	309	int nr;
	310	struct console *cons;
	311
	312	/*
	313	* these are private; the low level driver should not
	314	* touch these; they should be initialised to NULL
	315	*/
	316	struct uart_state *state;
	317	struct tty_driver *tty_driver;
	318	};
	319
	320	void uart_write_wakeup(struct uart_port *port);
	321
	322	/*
	323	* Baud rate helpers.
	324	*/
	325	void uart_update_timeout(struct uart_port *port, unsigned int cflag,
	326	unsigned int baud);
606d099c AC	327	unsigned int uart_get_baud_rate(struct uart_port port, struct ktermios termios,
606d099c AC	328	struct ktermios *old, unsigned int min,
1da177e4 LT	329	unsigned int max);
	330	unsigned int uart_get_divisor(struct uart_port *port, unsigned int baud);
	331
54381067 AV	332	/* Base timer interval for polling */
	333	static inline int uart_poll_timeout(struct uart_port *port)
	334	{
	335	int timeout = port->timeout;
	336
	337	return timeout > 6 ? (timeout / 2 - 2) : 1;
	338	}
	339
1da177e4 LT	340	/*
	341	* Console helpers.
	342	*/
9aac5887 RH	343	struct earlycon_device {
	344	struct console *con;
	345	struct uart_port port;
	346	char options[16]; /* e.g., 115200n8 */
	347	unsigned int baud;
	348	};
9aac5887	349
470ca0de	350	struct earlycon_id {
c1c734cb DA	351	char name[15];
c1c734cb DA	352	char name_term; /* In case compiler didn't '\0' term name */
2eaa7909	353	char compatible[128];
470ca0de	354	int (setup)(struct earlycon_device , const char *options);
dd709e72	355	};
470ca0de	356
dd709e72 DK	357	extern const struct earlycon_id *__earlycon_table[];
dd709e72 DK	358	extern const struct earlycon_id *__earlycon_table_end[];
2eaa7909	359
f8ba3647 MY	360	#if defined(CONFIG_SERIAL_EARLYCON) && !defined(MODULE)
	361	#define EARLYCON_USED_OR_UNUSED __used
	362	#else
	363	#define EARLYCON_USED_OR_UNUSED __maybe_unused
	364	#endif
	365
dd709e72 DK	366	#define _OF_EARLYCON_DECLARE(_name, compat, fn, unique_id) \
	367	static const struct earlycon_id unique_id \
	368	EARLYCON_USED_OR_UNUSED __initconst \
2eaa7909 PH	369	= { .name = __stringify(_name), \
2eaa7909 PH	370	.compatible = compat, \
dd709e72 DK	371	.setup = fn }; \
	372	static const struct earlycon_id EARLYCON_USED_OR_UNUSED \
	373	__section(__earlycon_table) \
	374	* const __PASTE(__p, unique_id) = &unique_id
	375
	376	#define OF_EARLYCON_DECLARE(_name, compat, fn) \
	377	_OF_EARLYCON_DECLARE(_name, compat, fn, \
	378	__UNIQUE_ID(__earlycon_##_name))
2eaa7909 PH	379
	380	#define EARLYCON_DECLARE(_name, fn) OF_EARLYCON_DECLARE(_name, "", fn)
	381
c90fe9c0	382	extern int of_setup_earlycon(const struct earlycon_id *match,
088da2a1	383	unsigned long node,
4d118c9a	384	const char *options);
b0b6abd3	385
ad1696f6	386	#ifdef CONFIG_SERIAL_EARLYCON
0231d000	387	extern bool earlycon_acpi_spcr_enable __initdata;
ad1696f6 AM	388	int setup_earlycon(char *buf);
ad1696f6 AM	389	#else
219c7b06	390	static const bool earlycon_acpi_spcr_enable EARLYCON_USED_OR_UNUSED;
ad1696f6 AM	391	static inline int setup_earlycon(char *buf) { return 0; }
	392	#endif
	393
1da177e4 LT	394	struct uart_port uart_get_console(struct uart_port ports, int nr,
1da177e4 LT	395	struct console *c);
46e36683	396	int uart_parse_earlycon(char p, unsigned char iotype, resource_size_t *addr,
73abaf87	397	char **options);
0f646b63	398	void uart_parse_options(const char options, int baud, int parity, int bits,
1da177e4 LT	399	int *flow);
	400	int uart_set_options(struct uart_port port, struct console co, int baud,
	401	int parity, int bits, int flow);
	402	struct tty_driver uart_console_device(struct console co, int *index);
d358788f RK	403	void uart_console_write(struct uart_port port, const char s,
	404	unsigned int count,
	405	void (putchar)(struct uart_port , int));
1da177e4 LT	406
	407	/*
	408	* Port/driver registration/removal
	409	*/
	410	int uart_register_driver(struct uart_driver *uart);
	411	void uart_unregister_driver(struct uart_driver *uart);
1da177e4 LT	412	int uart_add_one_port(struct uart_driver reg, struct uart_port port);
	413	int uart_remove_one_port(struct uart_driver reg, struct uart_port port);
	414	int uart_match_port(struct uart_port port1, struct uart_port port2);
	415
	416	/*
	417	* Power Management
	418	*/
	419	int uart_suspend_port(struct uart_driver reg, struct uart_port port);
	420	int uart_resume_port(struct uart_driver reg, struct uart_port port);
	421
	422	#define uart_circ_empty(circ) ((circ)->head == (circ)->tail)
	423	#define uart_circ_clear(circ) ((circ)->head = (circ)->tail = 0)
	424
	425	#define uart_circ_chars_pending(circ) \
	426	(CIRC_CNT((circ)->head, (circ)->tail, UART_XMIT_SIZE))
	427
	428	#define uart_circ_chars_free(circ) \
	429	(CIRC_SPACE((circ)->head, (circ)->tail, UART_XMIT_SIZE))
	430
f751928e AC	431	static inline int uart_tx_stopped(struct uart_port *port)
f751928e AC	432	{
ebd2c8f6	433	struct tty_struct *tty = port->state->port.tty;
a727b025	434	if ((tty && tty->stopped) \|\| port->hw_stopped)
f751928e AC	435	return 1;
	436	return 0;
	437	}
1da177e4	438
299245a1 PH	439	static inline bool uart_cts_enabled(struct uart_port *uport)
299245a1 PH	440	{
d4260b51	441	return !!(uport->status & UPSTAT_CTS_ENABLE);
299245a1 PH	442	}
299245a1 PH	443
391f93f2 PH	444	static inline bool uart_softcts_mode(struct uart_port *uport)
	445	{
	446	upstat_t mask = UPSTAT_CTS_ENABLE \| UPSTAT_AUTOCTS;
	447
	448	return ((uport->status & mask) == UPSTAT_CTS_ENABLE);
	449	}
	450
1da177e4 LT	451	/*
	452	* The following are helper functions for the low level drivers.
	453	*/
027d7dac JS	454
	455	extern void uart_handle_dcd_change(struct uart_port *uport,
	456	unsigned int status);
	457	extern void uart_handle_cts_change(struct uart_port *uport,
	458	unsigned int status);
	459
	460	extern void uart_insert_char(struct uart_port *port, unsigned int status,
	461	unsigned int overrun, unsigned int ch, unsigned int flag);
	462
732dbf3a	463	#if defined(SUPPORT_SYSRQ) && defined(CONFIG_MAGIC_SYSRQ_SERIAL)
1da177e4	464	static inline int
7d12e780	465	uart_handle_sysrq_char(struct uart_port *port, unsigned int ch)
1da177e4 LT	466	{
	467	if (port->sysrq) {
	468	if (ch && time_before(jiffies, port->sysrq)) {
f335397d	469	handle_sysrq(ch);
1da177e4 LT	470	port->sysrq = 0;
	471	return 1;
	472	}
	473	port->sysrq = 0;
	474	}
	475	return 0;
	476	}
d6e19358 DA	477	static inline int
	478	uart_prepare_sysrq_char(struct uart_port *port, unsigned int ch)
	479	{
	480	if (port->sysrq) {
	481	if (ch && time_before(jiffies, port->sysrq)) {
	482	port->sysrq_ch = ch;
	483	port->sysrq = 0;
	484	return 1;
	485	}
	486	port->sysrq = 0;
	487	}
	488	return 0;
	489	}
	490	static inline void
	491	uart_unlock_and_check_sysrq(struct uart_port *port, unsigned long irqflags)
	492	{
	493	int sysrq_ch;
	494
	495	sysrq_ch = port->sysrq_ch;
	496	port->sysrq_ch = 0;
	497
	498	spin_unlock_irqrestore(&port->lock, irqflags);
	499
	500	if (sysrq_ch)
	501	handle_sysrq(sysrq_ch);
	502	}
027d7dac	503	#else
d6e19358 DA	504	static inline int
	505	uart_handle_sysrq_char(struct uart_port *port, unsigned int ch) { return 0; }
	506	static inline int
	507	uart_prepare_sysrq_char(struct uart_port *port, unsigned int ch) { return 0; }
	508	static inline void
	509	uart_unlock_and_check_sysrq(struct uart_port *port, unsigned long irqflags)
	510	{
	511	spin_unlock_irqrestore(&port->lock, irqflags);
	512	}
4e149184	513	#endif
1da177e4 LT	514
	515	/*
	516	* We do the SysRQ and SAK checking like this...
	517	*/
	518	static inline int uart_handle_break(struct uart_port *port)
	519	{
ebd2c8f6	520	struct uart_state *state = port->state;
bf03f65b DW	521
	522	if (port->handle_break)
	523	port->handle_break(port);
	524
1da177e4 LT	525	#ifdef SUPPORT_SYSRQ
	526	if (port->cons && port->cons->index == port->line) {
	527	if (!port->sysrq) {
	528	port->sysrq = jiffies + HZ*5;
	529	return 1;
	530	}
	531	port->sysrq = 0;
	532	}
	533	#endif
27ae7a74	534	if (port->flags & UPF_SAK)
ebd2c8f6	535	do_SAK(state->port.tty);
1da177e4 LT	536	return 0;
	537	}
	538
1da177e4 LT	539	/*
	540	* UART_ENABLE_MS - determine if port should enable modem status irqs
	541	*/
	542	#define UART_ENABLE_MS(port,cflag) ((port)->flags & UPF_HARDPPS_CD \|\| \
	543	(cflag) & CRTSCTS \|\| \
	544	!((cflag) & CLOCAL))
	545
743f93f8	546	void uart_get_rs485_mode(struct device dev, struct serial_rs485 rs485conf);
1da177e4	547	#endif /* LINUX_SERIAL_CORE_H */