1 /*
2 * include/linux/serial.h
3 *
4 * Copyright (C) 1992 by Theodore Ts'o.
5 *
6 * Redistribution of this file is permitted under the terms of the GNU
7 * Public License (GPL)
8 */
9
10 /*
11 * This our internal structure for keeping track of interrupt service
12 * routines.
13 */
14 typedef struct struct_ISR *async_ISR;
15 struct struct_ISR {
16 int irq; /* The IRQ assigned for this device */
17 int port; /* The base port for this device */
18 /* (use is ISR specific) */
19 void (*ISR_proc)(async_ISR, int);
20 int line; /* The serial line (or base */
21 /* serial line) */
22 int refcnt; /* How many devices are depending on */
23 /* this interrupt (multiport boards) */
24 async_ISR next_ISR; /* For the linked list */
25 async_ISR prev_ISR;
26 };
27
28 /*
29 * This is our internal structure for each serial port's state.
30 *
31 * Many fields are paralleled by the structure used by the serial_struct
32 * structure.
33 *
34 * For definitions of the flags field, see tty.h
35 */
36
37 struct async_struct {
38 int baud_base;
39 int port;
40 async_ISR ISR;
41 int flags;
42 int type;
43 struct tty_struct *tty;
44 unsigned long timer;
45 int timeout;
46 int xmit_fifo_size;
47 int custom_divisor;
48 int x_char; /* xon/xoff characater */
49 int event;
50 int line;
51 };
52
53 /*
54 * Events are used to schedule things to happen at timer-interrupt
55 * time, instead of at rs interrupt time.
56 */
57 #define RS_EVENT_READ_PROCESS 0
58 #define RS_EVENT_WRITE_WAKEUP 1
59 #define RS_EVENT_HUP_PGRP 2
60 #define RS_EVENT_BREAK_INT 3
61 #define RS_EVENT_DO_SAK 4
62
63 /*
64 * These are the UART port assignments, expressed as offsets from the base
65 * register. These assignments should hold for any serial port based on
66 * a 8250, 16450, or 16550(A).
67 */
68 #define UART_RX 0 /* In: Receive buffer (DLAB=0) */
69 #define UART_TX 0 /* Out: Transmit buffer (DLAB=0) */
70 #define UART_DLL 0 /* Out: Devisor Latch Low (DLAB=1) */
71 #define UART_DLM 1 /* Out: Devisor Latch High (DLAB=1) */
72 #define UART_IER 1 /* Out: Interrupt Enable Register */
73 #define UART_IIR 2 /* In: Interrupt ID Register */
74 #define UART_FCR 2 /* Out: FIFO Control Register */
75 #define UART_LCR 3 /* Out: Line Control Register */
76 #define UART_MCR 4 /* Out: Modem Control Register */
77 #define UART_LSR 5 /* In: Line Status Register */
78 #define UART_MSR 6 /* In: Modem Status Register */
79 #define UART_SCR 7 /* I/O: Scratch Register */
80
81 /*
82 * These are the definitions for the FIFO Control Register
83 */
84 #define UART_FCR_ENABLE_FIFO 0x01 /* Enable the FIFO */
85 #define UART_FCR_CLEAR_RCVR 0x02 /* Clear the RCVR FIFO */
86 #define UART_FCR_CLEAR_XMIT 0x04 /* Clear the XMIT FIFO */
87 #define UART_FCR_DMA_SELECT 0x08 /* For DMA applications */
88 #define UART_FCR_TRIGGER_MASK 0xC0 /* Mask for the FIFO trigger range */
89 #define UART_FCR_TRIGGER_1 0x00 /* Mask for trigger set at 1 */
90 #define UART_FCR_TRIGGER_4 0x40 /* Mask for trigger set at 4 */
91 #define UART_FCR_TRIGGER_8 0x80 /* Mask for trigger set at 8 */
92 #define UART_FCR_TRIGGER_14 0xC0 /* Mask for trigger set at 14 */
93
94 #define UART_FCR_CLEAR_CMD (UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT)
95 #define UART_FCR_SETUP_CMD (UART_FCR_ENABLE_FIFO | UART_FCR_TRIGGER_14)
96
97 /*
98 * These are the definitions for the Line Control Register
99 *
100 * Note: if the word length is 5 bits (UART_LCR_WLEN5), then setting
101 * UART_LCR_STOP will select 1.5 stop bits, not 2 stop bits.
102 */
103 #define UART_LCR_DLAB 0x80 /* Devisor latch access bit */
104 #define UART_LCR_SBC 0x40 /* Set break control */
105 #define UART_LCR_SPAR 0x20 /* Stick parity (?) */
106 #define UART_LCR_EPAR 0x10 /* Even paraity select */
107 #define UART_LCR_PARITY 0x08 /* Parity Enable */
108 #define UART_LCR_STOP 0x04 /* Stop bits: 0=1 stop bit, 1= 2 stop bits */
109 #define UART_LCR_WLEN5 0x00 /* Wordlength: 5 bits */
110 #define UART_LCR_WLEN6 0x01 /* Wordlength: 6 bits */
111 #define UART_LCR_WLEN7 0x02 /* Wordlength: 7 bits */
112 #define UART_LCR_WLEN8 0x03 /* Wordlength: 8 bits */
113
114 /*
115 * These are the definitions for the Line Status Register
116 */
117 #define UART_LSR_TEMT 0x40 /* Transmitter empty */
118 #define UART_LSR_THRE 0x20 /* Transmit-hold-register empty */
119 #define UART_LSR_BI 0x10 /* Break interrupt indicator */
120 #define UART_LSR_FE 0x08 /* Frame error indicator */
121 #define UART_LSR_PE 0x04 /* Parity error indicator */
122 #define UART_LSR_OE 0x02 /* Overrun error indicator */
123 #define UART_LSR_DR 0x01 /* Receiver data ready */
124
125 /*
126 * These are the definitions for the Interrupt Indentification Register
127 */
128 #define UART_IIR_NO_INT 0x01 /* No interrupts pending */
129 #define UART_IIR_ID 0x06 /* Mask for the interrupt ID */
130
131 #define UART_IIR_MSI 0x00 /* Modem status interrupt */
132 #define UART_IIR_THRI 0x02 /* Transmitter holding register empty */
133 #define UART_IIR_RDI 0x04 /* Receiver data interrupt */
134 #define UART_IIR_RLSI 0x06 /* Receiver line status interrupt */
135
136 /*
137 * These are the definitions for the Interrupt Enable Register
138 */
139 #define UART_IER_MSI 0x08 /* Enable Modem status interrupt */
140 #define UART_IER_RLSI 0x04 /* Enable receiver line status interrupt */
141 #define UART_IER_THRI 0x02 /* Enable Transmitter holding register int. */
142 #define UART_IER_RDI 0x01 /* Enable receiver data interrupt */
143
144 /*
145 * These are the definitions for the Modem Control Register
146 */
147 #define UART_MCR_LOOP 0x10 /* Enable loopback test mode */
148 #define UART_MCR_OUT2 0x08 /* Out2 complement */
149 #define UART_MCR_OUT1 0x04 /* Out1 complement */
150 #define UART_MCR_RTS 0x02 /* RTS complement */
151 #define UART_MCR_DTR 0x01 /* DTR complement */
152
153 /*
154 * These are the definitions for the Modem Status Register
155 */
156 #define UART_MSR_DCD 0x80 /* Data Carrier Detect */
157 #define UART_MSR_RI 0x40 /* Ring Indicator */
158 #define UART_MSR_DSR 0x20 /* Data Set Ready */
159 #define UART_MSR_CTS 0x10 /* Clear to Send */
160 #define UART_MSR_DDCD 0x08 /* Delta DCD */
161 #define UART_MSR_TERI 0x04 /* Trailing edge ring indicator */
162 #define UART_MSR_DDSR 0x02 /* Delta DSR */
163 #define UART_MSR_DCTS 0x01 /* Delta CTS */
164 #define UART_MSR_ANY_DELTA 0x0F /* Any of the delta bits! */