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 			               const 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 	void		(*setup_timer)(struct uart_8250_port *);
78 };
79 
80 struct uart_8250_em485 {
81 	struct hrtimer		start_tx_timer; /* "rs485 start tx" timer */
82 	struct hrtimer		stop_tx_timer;  /* "rs485 stop tx" timer */
83 	struct hrtimer		*active_timer;  /* pointer to active timer */
84 	struct uart_8250_port	*port;          /* for hrtimer callbacks */
85 	unsigned int		tx_stopped:1;	/* tx is currently stopped */
86 };
87 
88 /*
89  * This should be used by drivers which want to register
90  * their own 8250 ports without registering their own
91  * platform device.  Using these will make your driver
92  * dependent on the 8250 driver.
93  */
94 
95 struct uart_8250_port {
96 	struct uart_port	port;
97 	struct timer_list	timer;		/* "no irq" timer */
98 	struct list_head	list;		/* ports on this IRQ */
99 	u32			capabilities;	/* port capabilities */
100 	unsigned short		bugs;		/* port bugs */
101 	bool			fifo_bug;	/* min RX trigger if enabled */
102 	unsigned int		tx_loadsz;	/* transmit fifo load size */
103 	unsigned char		acr;
104 	unsigned char		fcr;
105 	unsigned char		ier;
106 	unsigned char		lcr;
107 	unsigned char		mcr;
108 	unsigned char		cur_iotype;	/* Running I/O type */
109 	unsigned int		rpm_tx_active;
110 	unsigned char		canary;		/* non-zero during system sleep
111 						 *   if no_console_suspend
112 						 */
113 	unsigned char		probe;
114 	struct mctrl_gpios	*gpios;
115 #define UART_PROBE_RSA	(1 << 0)
116 
117 	/*
118 	 * Some bits in registers are cleared on a read, so they must
119 	 * be saved whenever the register is read but the bits will not
120 	 * be immediately processed.
121 	 */
122 #define LSR_SAVE_FLAGS UART_LSR_BRK_ERROR_BITS
123 	u16			lsr_saved_flags;
124 	u16			lsr_save_mask;
125 #define MSR_SAVE_FLAGS UART_MSR_ANY_DELTA
126 	unsigned char		msr_saved_flags;
127 
128 	struct uart_8250_dma	*dma;
129 	const struct uart_8250_ops *ops;
130 
131 	/* 8250 specific callbacks */
132 	int			(*dl_read)(struct uart_8250_port *);
133 	void			(*dl_write)(struct uart_8250_port *, int);
134 
135 	struct uart_8250_em485 *em485;
136 	void			(*rs485_start_tx)(struct uart_8250_port *);
137 	void			(*rs485_stop_tx)(struct uart_8250_port *);
138 
139 	/* Serial port overrun backoff */
140 	struct delayed_work overrun_backoff;
141 	u32 overrun_backoff_time_ms;
142 };
143 
up_to_u8250p(struct uart_port * up)144 static inline struct uart_8250_port *up_to_u8250p(struct uart_port *up)
145 {
146 	return container_of(up, struct uart_8250_port, port);
147 }
148 
149 int serial8250_register_8250_port(const struct uart_8250_port *);
150 void serial8250_unregister_port(int line);
151 void serial8250_suspend_port(int line);
152 void serial8250_resume_port(int line);
153 
154 extern int early_serial_setup(struct uart_port *port);
155 
156 extern int early_serial8250_setup(struct earlycon_device *device,
157 					 const char *options);
158 extern void serial8250_update_uartclk(struct uart_port *port,
159 				      unsigned int uartclk);
160 extern void serial8250_do_set_termios(struct uart_port *port,
161 		struct ktermios *termios, const struct ktermios *old);
162 extern void serial8250_do_set_ldisc(struct uart_port *port,
163 				    struct ktermios *termios);
164 extern unsigned int serial8250_do_get_mctrl(struct uart_port *port);
165 extern int serial8250_do_startup(struct uart_port *port);
166 extern void serial8250_do_shutdown(struct uart_port *port);
167 extern void serial8250_do_pm(struct uart_port *port, unsigned int state,
168 			     unsigned int oldstate);
169 extern void serial8250_do_set_mctrl(struct uart_port *port, unsigned int mctrl);
170 extern void serial8250_do_set_divisor(struct uart_port *port, unsigned int baud,
171 				      unsigned int quot,
172 				      unsigned int quot_frac);
173 extern int fsl8250_handle_irq(struct uart_port *port);
174 int serial8250_handle_irq(struct uart_port *port, unsigned int iir);
175 u16 serial8250_rx_chars(struct uart_8250_port *up, u16 lsr);
176 void serial8250_read_char(struct uart_8250_port *up, u16 lsr);
177 void serial8250_tx_chars(struct uart_8250_port *up);
178 unsigned int serial8250_modem_status(struct uart_8250_port *up);
179 void serial8250_init_port(struct uart_8250_port *up);
180 void serial8250_set_defaults(struct uart_8250_port *up);
181 void serial8250_console_write(struct uart_8250_port *up, const char *s,
182 			      unsigned int count);
183 int serial8250_console_setup(struct uart_port *port, char *options, bool probe);
184 int serial8250_console_exit(struct uart_port *port);
185 
186 extern void serial8250_set_isa_configurator(void (*v)
187 					(int port, struct uart_port *up,
188 						u32 *capabilities));
189 
190 #ifdef CONFIG_SERIAL_8250_RT288X
191 unsigned int au_serial_in(struct uart_port *p, int offset);
192 void au_serial_out(struct uart_port *p, int offset, int value);
193 #endif
194 
195 #endif
196