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/errno.h>
11#include <linux/serial_core.h>
12#include <linux/serial_reg.h>
13#include <linux/platform_device.h>
14
15struct uart_8250_port;
16
17/*
18 * This is the platform device platform_data structure
19 *
20 * @mapsize: Port size for ioremap()
21 * @bugs: Port bugs
22 *
23 * @dl_read: ``u32 ()(struct uart_8250_port *up)``
24 *
25 * UART divisor latch read.
26 *
27 * @dl_write: ``void ()(struct uart_8250_port *up, u32 value)``
28 *
29 * Write @value into UART divisor latch.
30 *
31 * Locking: Caller holds port's lock.
32 */
33struct plat_serial8250_port {
34 unsigned long iobase; /* io base address */
35 void __iomem *membase; /* ioremap cookie or NULL */
36 resource_size_t mapbase; /* resource base */
37 resource_size_t mapsize;
38 unsigned int uartclk; /* UART clock rate */
39 unsigned int irq; /* interrupt number */
40 unsigned long irqflags; /* request_irq flags */
41 void *private_data;
42 unsigned char regshift; /* register shift */
43 unsigned char iotype; /* UPIO_* */
44 unsigned char hub6;
45 unsigned char has_sysrq; /* supports magic SysRq */
46 unsigned int type; /* If UPF_FIXED_TYPE */
47 upf_t flags; /* UPF_* flags */
48 u16 bugs; /* port bugs */
49 u32 (*serial_in)(struct uart_port *, unsigned int offset);
50 void (*serial_out)(struct uart_port *, unsigned int offset, u32 val);
51 u32 (*dl_read)(struct uart_8250_port *up);
52 void (*dl_write)(struct uart_8250_port *up, u32 value);
53 void (*set_termios)(struct uart_port *,
54 struct ktermios *new,
55 const struct ktermios *old);
56 void (*set_ldisc)(struct uart_port *,
57 struct ktermios *);
58 unsigned int (*get_mctrl)(struct uart_port *);
59 int (*handle_irq)(struct uart_port *);
60 void (*pm)(struct uart_port *, unsigned int state,
61 unsigned old);
62 void (*handle_break)(struct uart_port *);
63};
64
65/*
66 * Allocate 8250 platform device IDs. Nothing is implied by
67 * the numbering here, except for the legacy entry being -1.
68 */
69enum {
70 PLAT8250_DEV_LEGACY = -1,
71 PLAT8250_DEV_PLATFORM,
72 PLAT8250_DEV_PLATFORM1,
73 PLAT8250_DEV_PLATFORM2,
74 PLAT8250_DEV_FOURPORT,
75 PLAT8250_DEV_ACCENT,
76 PLAT8250_DEV_BOCA,
77 PLAT8250_DEV_EXAR_ST16C554,
78 PLAT8250_DEV_HUB6,
79 PLAT8250_DEV_AU1X00,
80 PLAT8250_DEV_SM501,
81};
82
83struct uart_8250_dma;
84struct uart_8250_port;
85
86/**
87 * 8250 core driver operations
88 *
89 * @setup_irq() Setup irq handling. The universal 8250 driver links this
90 * port to the irq chain. Other drivers may @request_irq().
91 * @release_irq() Undo irq handling. The universal 8250 driver unlinks
92 * the port from the irq chain.
93 */
94struct uart_8250_ops {
95 int (*setup_irq)(struct uart_8250_port *);
96 void (*release_irq)(struct uart_8250_port *);
97 void (*setup_timer)(struct uart_8250_port *);
98};
99
100struct uart_8250_em485 {
101 struct hrtimer start_tx_timer; /* "rs485 start tx" timer */
102 struct hrtimer stop_tx_timer; /* "rs485 stop tx" timer */
103 struct hrtimer *active_timer; /* pointer to active timer */
104 struct uart_8250_port *port; /* for hrtimer callbacks */
105 unsigned int tx_stopped:1; /* tx is currently stopped */
106};
107
108/*
109 * This should be used by drivers which want to register
110 * their own 8250 ports without registering their own
111 * platform device. Using these will make your driver
112 * dependent on the 8250 driver.
113 *
114 * @dl_read: ``u32 ()(struct uart_8250_port *port)``
115 *
116 * UART divisor latch read.
117 *
118 * @dl_write: ``void ()(struct uart_8250_port *port, u32 value)``
119 *
120 * Write @value into UART divisor latch.
121 *
122 * Locking: Caller holds port's lock.
123 */
124struct uart_8250_port {
125 struct uart_port port;
126 struct timer_list timer; /* "no irq" timer */
127 struct list_head list; /* ports on this IRQ */
128 u32 capabilities; /* port capabilities */
129 u16 bugs; /* port bugs */
130 unsigned int tx_loadsz; /* transmit fifo load size */
131 unsigned char acr;
132 unsigned char fcr;
133 unsigned char ier;
134 unsigned char lcr;
135 unsigned char mcr;
136 unsigned char cur_iotype; /* Running I/O type */
137 unsigned int rpm_tx_active;
138 unsigned char canary; /* non-zero during system sleep
139 * if no_console_suspend
140 */
141 unsigned char probe;
142 struct mctrl_gpios *gpios;
143#define UART_PROBE_RSA (1 << 0)
144
145 /*
146 * Some bits in registers are cleared on a read, so they must
147 * be saved whenever the register is read but the bits will not
148 * be immediately processed.
149 */
150#define LSR_SAVE_FLAGS UART_LSR_BRK_ERROR_BITS
151 u16 lsr_saved_flags;
152 u16 lsr_save_mask;
153#define MSR_SAVE_FLAGS UART_MSR_ANY_DELTA
154 unsigned char msr_saved_flags;
155
156 struct uart_8250_dma *dma;
157 const struct uart_8250_ops *ops;
158
159 /* 8250 specific callbacks */
160 u32 (*dl_read)(struct uart_8250_port *up);
161 void (*dl_write)(struct uart_8250_port *up, u32 value);
162
163 struct uart_8250_em485 *em485;
164 void (*rs485_start_tx)(struct uart_8250_port *up, bool toggle_ier);
165 void (*rs485_stop_tx)(struct uart_8250_port *up, bool toggle_ier);
166
167 /* Serial port overrun backoff */
168 struct delayed_work overrun_backoff;
169 u32 overrun_backoff_time_ms;
170};
171
172static inline struct uart_8250_port *up_to_u8250p(struct uart_port *up)
173{
174 return container_of(up, struct uart_8250_port, port);
175}
176
177int serial8250_register_8250_port(const struct uart_8250_port *);
178void serial8250_unregister_port(int line);
179void serial8250_suspend_port(int line);
180void serial8250_resume_port(int line);
181
182int early_serial_setup(struct uart_port *port);
183int early_serial8250_setup(struct earlycon_device *device, const char *options);
184
185void serial8250_update_uartclk(struct uart_port *port, unsigned int uartclk);
186void serial8250_do_set_termios(struct uart_port *port, struct ktermios *termios,
187 const struct ktermios *old);
188void serial8250_do_set_ldisc(struct uart_port *port, struct ktermios *termios);
189unsigned int serial8250_do_get_mctrl(struct uart_port *port);
190int serial8250_do_startup(struct uart_port *port);
191void serial8250_do_shutdown(struct uart_port *port);
192void serial8250_do_pm(struct uart_port *port, unsigned int state,
193 unsigned int oldstate);
194void serial8250_do_set_mctrl(struct uart_port *port, unsigned int mctrl);
195void serial8250_do_set_divisor(struct uart_port *port, unsigned int baud,
196 unsigned int quot);
197int fsl8250_handle_irq(struct uart_port *port);
198int serial8250_handle_irq(struct uart_port *port, unsigned int iir);
199u16 serial8250_rx_chars(struct uart_8250_port *up, u16 lsr);
200void serial8250_read_char(struct uart_8250_port *up, u16 lsr);
201void serial8250_tx_chars(struct uart_8250_port *up);
202unsigned int serial8250_modem_status(struct uart_8250_port *up);
203void serial8250_init_port(struct uart_8250_port *up);
204void serial8250_set_defaults(struct uart_8250_port *up);
205void serial8250_console_write(struct uart_8250_port *up, const char *s,
206 unsigned int count);
207int serial8250_console_setup(struct uart_port *port, char *options, bool probe);
208int serial8250_console_exit(struct uart_port *port);
209
210void serial8250_set_isa_configurator(void (*v)(int port, struct uart_port *up,
211 u32 *capabilities));
212
213#ifdef CONFIG_SERIAL_8250_CONSOLE
214extern int hp300_setup_serial_console(void) __init;
215#else
216static inline int hp300_setup_serial_console(void) { return 0; }
217#endif
218
219#ifdef CONFIG_SERIAL_8250_RT288X
220int rt288x_setup(struct uart_port *p);
221int au_platform_setup(struct plat_serial8250_port *p);
222#else
223static inline int rt288x_setup(struct uart_port *p) { return -ENODEV; }
224static inline int au_platform_setup(struct plat_serial8250_port *p) { return -ENODEV; }
225#endif
226
227#endif
228