1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /*
3  *  linux/include/linux/serial_8250.h
4  *
5  *  Copyright (C) 2004 Russell King
6  */
7 #ifndef _LINUX_SERIAL_8250_H
8 #define _LINUX_SERIAL_8250_H
9 
10 #include <linux/serial_core.h>
11 #include <linux/serial_reg.h>
12 #include <linux/platform_device.h>
13 
14 /*
15  * This is the platform device platform_data structure
16  */
17 struct plat_serial8250_port {
18 	unsigned long	iobase;		/* io base address */
19 	void __iomem	*membase;	/* ioremap cookie or NULL */
20 	resource_size_t	mapbase;	/* resource base */
21 	unsigned int	irq;		/* interrupt number */
22 	unsigned long	irqflags;	/* request_irq flags */
23 	unsigned int	uartclk;	/* UART clock rate */
24 	void            *private_data;
25 	unsigned char	regshift;	/* register shift */
26 	unsigned char	iotype;		/* UPIO_* */
27 	unsigned char	hub6;
28 	unsigned char	has_sysrq;	/* supports magic SysRq */
29 	upf_t		flags;		/* UPF_* flags */
30 	unsigned int	type;		/* If UPF_FIXED_TYPE */
31 	unsigned int	(*serial_in)(struct uart_port *, int);
32 	void		(*serial_out)(struct uart_port *, int, int);
33 	void		(*set_termios)(struct uart_port *,
34 			               struct ktermios *new,
35 			               struct ktermios *old);
36 	void		(*set_ldisc)(struct uart_port *,
37 				     struct ktermios *);
38 	unsigned int	(*get_mctrl)(struct uart_port *);
39 	int		(*handle_irq)(struct uart_port *);
40 	void		(*pm)(struct uart_port *, unsigned int state,
41 			      unsigned old);
42 	void		(*handle_break)(struct uart_port *);
43 };
44 
45 /*
46  * Allocate 8250 platform device IDs.  Nothing is implied by
47  * the numbering here, except for the legacy entry being -1.
48  */
49 enum {
50 	PLAT8250_DEV_LEGACY = -1,
51 	PLAT8250_DEV_PLATFORM,
52 	PLAT8250_DEV_PLATFORM1,
53 	PLAT8250_DEV_PLATFORM2,
54 	PLAT8250_DEV_FOURPORT,
55 	PLAT8250_DEV_ACCENT,
56 	PLAT8250_DEV_BOCA,
57 	PLAT8250_DEV_EXAR_ST16C554,
58 	PLAT8250_DEV_HUB6,
59 	PLAT8250_DEV_AU1X00,
60 	PLAT8250_DEV_SM501,
61 };
62 
63 struct uart_8250_dma;
64 struct uart_8250_port;
65 
66 /**
67  * 8250 core driver operations
68  *
69  * @setup_irq()		Setup irq handling. The universal 8250 driver links this
70  *			port to the irq chain. Other drivers may @request_irq().
71  * @release_irq()	Undo irq handling. The universal 8250 driver unlinks
72  *			the port from the irq chain.
73  */
74 struct uart_8250_ops {
75 	int		(*setup_irq)(struct uart_8250_port *);
76 	void		(*release_irq)(struct uart_8250_port *);
77 };
78 
79 struct uart_8250_em485 {
80 	struct hrtimer		start_tx_timer; /* "rs485 start tx" timer */
81 	struct hrtimer		stop_tx_timer;  /* "rs485 stop tx" timer */
82 	struct hrtimer		*active_timer;  /* pointer to active timer */
83 	struct uart_8250_port	*port;          /* for hrtimer callbacks */
84 	unsigned int		tx_stopped:1;	/* tx is currently stopped */
85 };
86 
87 /*
88  * This should be used by drivers which want to register
89  * their own 8250 ports without registering their own
90  * platform device.  Using these will make your driver
91  * dependent on the 8250 driver.
92  */
93 
94 struct uart_8250_port {
95 	struct uart_port	port;
96 	struct timer_list	timer;		/* "no irq" timer */
97 	struct list_head	list;		/* ports on this IRQ */
98 	u32			capabilities;	/* port capabilities */
99 	unsigned short		bugs;		/* port bugs */
100 	bool			fifo_bug;	/* min RX trigger if enabled */
101 	unsigned int		tx_loadsz;	/* transmit fifo load size */
102 	unsigned char		acr;
103 	unsigned char		fcr;
104 	unsigned char		ier;
105 	unsigned char		lcr;
106 	unsigned char		mcr;
107 	unsigned char		cur_iotype;	/* Running I/O type */
108 	unsigned int		rpm_tx_active;
109 	unsigned char		canary;		/* non-zero during system sleep
110 						 *   if no_console_suspend
111 						 */
112 	unsigned char		probe;
113 	struct mctrl_gpios	*gpios;
114 #define UART_PROBE_RSA	(1 << 0)
115 
116 	/*
117 	 * Some bits in registers are cleared on a read, so they must
118 	 * be saved whenever the register is read but the bits will not
119 	 * be immediately processed.
120 	 */
121 #define LSR_SAVE_FLAGS UART_LSR_BRK_ERROR_BITS
122 	unsigned char		lsr_saved_flags;
123 #define MSR_SAVE_FLAGS UART_MSR_ANY_DELTA
124 	unsigned char		msr_saved_flags;
125 
126 	struct uart_8250_dma	*dma;
127 	const struct uart_8250_ops *ops;
128 
129 	/* 8250 specific callbacks */
130 	int			(*dl_read)(struct uart_8250_port *);
131 	void			(*dl_write)(struct uart_8250_port *, int);
132 
133 	struct uart_8250_em485 *em485;
134 	void			(*rs485_start_tx)(struct uart_8250_port *);
135 	void			(*rs485_stop_tx)(struct uart_8250_port *);
136 
137 	/* Serial port overrun backoff */
138 	struct delayed_work overrun_backoff;
139 	u32 overrun_backoff_time_ms;
140 };
141 
up_to_u8250p(struct uart_port * up)142 static inline struct uart_8250_port *up_to_u8250p(struct uart_port *up)
143 {
144 	return container_of(up, struct uart_8250_port, port);
145 }
146 
147 int serial8250_register_8250_port(const struct uart_8250_port *);
148 void serial8250_unregister_port(int line);
149 void serial8250_suspend_port(int line);
150 void serial8250_resume_port(int line);
151 
152 extern int early_serial_setup(struct uart_port *port);
153 
154 extern int early_serial8250_setup(struct earlycon_device *device,
155 					 const char *options);
156 extern void serial8250_update_uartclk(struct uart_port *port,
157 				      unsigned int uartclk);
158 extern void serial8250_do_set_termios(struct uart_port *port,
159 		struct ktermios *termios, struct ktermios *old);
160 extern void serial8250_do_set_ldisc(struct uart_port *port,
161 				    struct ktermios *termios);
162 extern unsigned int serial8250_do_get_mctrl(struct uart_port *port);
163 extern int serial8250_do_startup(struct uart_port *port);
164 extern void serial8250_do_shutdown(struct uart_port *port);
165 extern void serial8250_do_pm(struct uart_port *port, unsigned int state,
166 			     unsigned int oldstate);
167 extern void serial8250_do_set_mctrl(struct uart_port *port, unsigned int mctrl);
168 extern void serial8250_do_set_divisor(struct uart_port *port, unsigned int baud,
169 				      unsigned int quot,
170 				      unsigned int quot_frac);
171 extern int fsl8250_handle_irq(struct uart_port *port);
172 int serial8250_handle_irq(struct uart_port *port, unsigned int iir);
173 unsigned char serial8250_rx_chars(struct uart_8250_port *up, unsigned char lsr);
174 void serial8250_read_char(struct uart_8250_port *up, unsigned char lsr);
175 void serial8250_tx_chars(struct uart_8250_port *up);
176 unsigned int serial8250_modem_status(struct uart_8250_port *up);
177 void serial8250_init_port(struct uart_8250_port *up);
178 void serial8250_set_defaults(struct uart_8250_port *up);
179 void serial8250_console_write(struct uart_8250_port *up, const char *s,
180 			      unsigned int count);
181 int serial8250_console_setup(struct uart_port *port, char *options, bool probe);
182 int serial8250_console_exit(struct uart_port *port);
183 
184 extern void serial8250_set_isa_configurator(void (*v)
185 					(int port, struct uart_port *up,
186 						u32 *capabilities));
187 
188 #ifdef CONFIG_SERIAL_8250_RT288X
189 unsigned int au_serial_in(struct uart_port *p, int offset);
190 void au_serial_out(struct uart_port *p, int offset, int value);
191 #endif
192 
193 #endif
194