serial: core: Document and assert lock requirements for irq helpers
[deliverable/linux.git] / include / linux / serial_core.h
CommitLineData
1da177e4
LT
1/*
2 * linux/drivers/char/serial_core.h
3 *
4 * Copyright (C) 2000 Deep Blue Solutions Ltd.
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
19 */
20#ifndef LINUX_SERIAL_CORE_H
21#define LINUX_SERIAL_CORE_H
22
1da177e4 23
661f83a6 24#include <linux/compiler.h>
1da177e4
LT
25#include <linux/interrupt.h>
26#include <linux/circ_buf.h>
27#include <linux/spinlock.h>
28#include <linux/sched.h>
29#include <linux/tty.h>
e2862f6a 30#include <linux/mutex.h>
b11115c1 31#include <linux/sysrq.h>
607ca46e 32#include <uapi/linux/serial_core.h>
1da177e4 33
cf0ebee0
SP
34#ifdef CONFIG_SERIAL_CORE_CONSOLE
35#define uart_console(port) \
36 ((port)->cons && (port)->cons->index == (port)->line)
37#else
38#define uart_console(port) (0)
39#endif
40
1da177e4 41struct uart_port;
1da177e4
LT
42struct serial_struct;
43struct device;
44
45/*
e759d7c5
KC
46 * This structure describes all the operations that can be done on the
47 * physical hardware. See Documentation/serial/driver for details.
1da177e4
LT
48 */
49struct uart_ops {
50 unsigned int (*tx_empty)(struct uart_port *);
51 void (*set_mctrl)(struct uart_port *, unsigned int mctrl);
52 unsigned int (*get_mctrl)(struct uart_port *);
b129a8cc
RK
53 void (*stop_tx)(struct uart_port *);
54 void (*start_tx)(struct uart_port *);
9aba8d5b
RK
55 void (*throttle)(struct uart_port *);
56 void (*unthrottle)(struct uart_port *);
1da177e4
LT
57 void (*send_xchar)(struct uart_port *, char ch);
58 void (*stop_rx)(struct uart_port *);
59 void (*enable_ms)(struct uart_port *);
60 void (*break_ctl)(struct uart_port *, int ctl);
61 int (*startup)(struct uart_port *);
62 void (*shutdown)(struct uart_port *);
6bb0e3a5 63 void (*flush_buffer)(struct uart_port *);
606d099c
AC
64 void (*set_termios)(struct uart_port *, struct ktermios *new,
65 struct ktermios *old);
d87d9b7d 66 void (*set_ldisc)(struct uart_port *, int new);
1da177e4
LT
67 void (*pm)(struct uart_port *, unsigned int state,
68 unsigned int oldstate);
1da177e4
LT
69
70 /*
71 * Return a string describing the type of the port
72 */
e759d7c5 73 const char *(*type)(struct uart_port *);
1da177e4
LT
74
75 /*
76 * Release IO and memory resources used by the port.
77 * This includes iounmap if necessary.
78 */
79 void (*release_port)(struct uart_port *);
80
81 /*
82 * Request IO and memory resources used by the port.
83 * This includes iomapping the port if necessary.
84 */
85 int (*request_port)(struct uart_port *);
86 void (*config_port)(struct uart_port *, int);
87 int (*verify_port)(struct uart_port *, struct serial_struct *);
88 int (*ioctl)(struct uart_port *, unsigned int, unsigned long);
f2d937f3 89#ifdef CONFIG_CONSOLE_POLL
c7f3e708 90 int (*poll_init)(struct uart_port *);
e759d7c5 91 void (*poll_put_char)(struct uart_port *, unsigned char);
f2d937f3
JW
92 int (*poll_get_char)(struct uart_port *);
93#endif
1da177e4
LT
94};
95
f5316b4a 96#define NO_POLL_CHAR 0x00ff0000
1da177e4
LT
97#define UART_CONFIG_TYPE (1 << 0)
98#define UART_CONFIG_IRQ (1 << 1)
99
100struct uart_icount {
101 __u32 cts;
102 __u32 dsr;
103 __u32 rng;
104 __u32 dcd;
105 __u32 rx;
106 __u32 tx;
107 __u32 frame;
108 __u32 overrun;
109 __u32 parity;
110 __u32 brk;
111 __u32 buf_overrun;
112};
113
0077d45e
RK
114typedef unsigned int __bitwise__ upf_t;
115
1da177e4
LT
116struct uart_port {
117 spinlock_t lock; /* port lock */
0c8946d9 118 unsigned long iobase; /* in/out[bwl] */
1da177e4 119 unsigned char __iomem *membase; /* read/write[bwl] */
7d6a07d1
DD
120 unsigned int (*serial_in)(struct uart_port *, int);
121 void (*serial_out)(struct uart_port *, int, int);
235dae5d
PL
122 void (*set_termios)(struct uart_port *,
123 struct ktermios *new,
124 struct ktermios *old);
b99b121b
SAS
125 int (*startup)(struct uart_port *port);
126 void (*shutdown)(struct uart_port *port);
a74036f5 127 int (*handle_irq)(struct uart_port *);
c161afe9
ML
128 void (*pm)(struct uart_port *, unsigned int state,
129 unsigned int old);
bf03f65b 130 void (*handle_break)(struct uart_port *);
1da177e4 131 unsigned int irq; /* irq number */
1c2f0493 132 unsigned long irqflags; /* irq flags */
1da177e4 133 unsigned int uartclk; /* base uart clock */
947deee8 134 unsigned int fifosize; /* tx fifo size */
1da177e4
LT
135 unsigned char x_char; /* xon/xoff char */
136 unsigned char regshift; /* reg offset shift */
137 unsigned char iotype; /* io access style */
947deee8 138 unsigned char unused1;
1da177e4
LT
139
140#define UPIO_PORT (0)
141#define UPIO_HUB6 (1)
142#define UPIO_MEM (2)
143#define UPIO_MEM32 (3)
c420811f 144#define UPIO_AU (4) /* Au1x00 and RT288x type IO */
3be91ec7 145#define UPIO_TSI (5) /* Tsi108/109 type IO */
1da177e4
LT
146
147 unsigned int read_status_mask; /* driver specific */
148 unsigned int ignore_status_mask; /* driver specific */
ebd2c8f6 149 struct uart_state *state; /* pointer to parent state */
1da177e4
LT
150 struct uart_icount icount; /* statistics */
151
152 struct console *cons; /* struct console, if any */
06e82df0 153#if defined(CONFIG_SERIAL_CORE_CONSOLE) || defined(SUPPORT_SYSRQ)
1da177e4
LT
154 unsigned long sysrq; /* sysrq timeout */
155#endif
156
8a949b07 157 /* flags must be updated while holding port mutex */
0077d45e
RK
158 upf_t flags;
159
160#define UPF_FOURPORT ((__force upf_t) (1 << 1))
161#define UPF_SAK ((__force upf_t) (1 << 2))
162#define UPF_SPD_MASK ((__force upf_t) (0x1030))
163#define UPF_SPD_HI ((__force upf_t) (0x0010))
164#define UPF_SPD_VHI ((__force upf_t) (0x0020))
165#define UPF_SPD_CUST ((__force upf_t) (0x0030))
166#define UPF_SPD_SHI ((__force upf_t) (0x1000))
167#define UPF_SPD_WARP ((__force upf_t) (0x1010))
168#define UPF_SKIP_TEST ((__force upf_t) (1 << 6))
169#define UPF_AUTO_IRQ ((__force upf_t) (1 << 7))
170#define UPF_HARDPPS_CD ((__force upf_t) (1 << 11))
171#define UPF_LOW_LATENCY ((__force upf_t) (1 << 13))
172#define UPF_BUGGY_UART ((__force upf_t) (1 << 14))
b6adea33 173#define UPF_NO_TXEN_TEST ((__force upf_t) (1 << 15))
0077d45e 174#define UPF_MAGIC_MULTIPLIER ((__force upf_t) (1 << 16))
dba05832
RK
175/* Port has hardware-assisted h/w flow control (iow, auto-RTS *not* auto-CTS) */
176#define UPF_HARD_FLOW ((__force upf_t) (1 << 21))
2cbacafd
RK
177/* Port has hardware-assisted s/w flow control */
178#define UPF_SOFT_FLOW ((__force upf_t) (1 << 22))
0077d45e
RK
179#define UPF_CONS_FLOW ((__force upf_t) (1 << 23))
180#define UPF_SHARE_IRQ ((__force upf_t) (1 << 24))
06315348 181#define UPF_EXAR_EFR ((__force upf_t) (1 << 25))
bc02d15a 182#define UPF_BUG_THRE ((__force upf_t) (1 << 26))
8e23fcc8
DD
183/* The exact UART type is known and should not be probed. */
184#define UPF_FIXED_TYPE ((__force upf_t) (1 << 27))
0077d45e 185#define UPF_BOOT_AUTOCONF ((__force upf_t) (1 << 28))
abb4a239 186#define UPF_FIXED_PORT ((__force upf_t) (1 << 29))
68ac64cd 187#define UPF_DEAD ((__force upf_t) (1 << 30))
0077d45e
RK
188#define UPF_IOREMAP ((__force upf_t) (1 << 31))
189
190#define UPF_CHANGE_MASK ((__force upf_t) (0x17fff))
191#define UPF_USR_MASK ((__force upf_t) (UPF_SPD_MASK|UPF_LOW_LATENCY))
1da177e4
LT
192
193 unsigned int mctrl; /* current modem ctrl settings */
194 unsigned int timeout; /* character-based timeout */
195 unsigned int type; /* port type */
ba899dbc 196 const struct uart_ops *ops;
1da177e4
LT
197 unsigned int custom_divisor;
198 unsigned int line; /* port index */
4f640efb 199 resource_size_t mapbase; /* for ioremap */
1da177e4
LT
200 struct device *dev; /* parent device */
201 unsigned char hub6; /* this should be in the 8250 driver */
b3b708fa 202 unsigned char suspended;
3f960dbb 203 unsigned char irq_wake;
b3b708fa 204 unsigned char unused[2];
266dcff0
GKH
205 struct attribute_group *attr_group; /* port specific attributes */
206 const struct attribute_group **tty_groups; /* all attributes (serial core use only) */
beab697a 207 void *private_data; /* generic platform data pointer */
1da177e4
LT
208};
209
927353a7
PG
210static inline int serial_port_in(struct uart_port *up, int offset)
211{
212 return up->serial_in(up, offset);
213}
214
215static inline void serial_port_out(struct uart_port *up, int offset, int value)
216{
217 up->serial_out(up, offset, value);
218}
219
6f538fe3
LW
220/**
221 * enum uart_pm_state - power states for UARTs
222 * @UART_PM_STATE_ON: UART is powered, up and operational
223 * @UART_PM_STATE_OFF: UART is powered off
224 * @UART_PM_STATE_UNDEFINED: sentinel
225 */
226enum uart_pm_state {
227 UART_PM_STATE_ON = 0,
228 UART_PM_STATE_OFF = 3, /* number taken from ACPI */
229 UART_PM_STATE_UNDEFINED,
230};
231
ebd2c8f6
AC
232/*
233 * This is the state information which is persistent across opens.
ebd2c8f6
AC
234 */
235struct uart_state {
df4f4dd4 236 struct tty_port port;
ebd2c8f6 237
6f538fe3 238 enum uart_pm_state pm_state;
1da177e4 239 struct circ_buf xmit;
1da177e4 240
ebd2c8f6 241 struct uart_port *uart_port;
f751928e
AC
242};
243
244#define UART_XMIT_SIZE PAGE_SIZE
245
246
1da177e4
LT
247/* number of characters left in xmit buffer before we ask for more */
248#define WAKEUP_CHARS 256
249
250struct module;
251struct tty_driver;
252
253struct uart_driver {
254 struct module *owner;
255 const char *driver_name;
256 const char *dev_name;
1da177e4
LT
257 int major;
258 int minor;
259 int nr;
260 struct console *cons;
261
262 /*
263 * these are private; the low level driver should not
264 * touch these; they should be initialised to NULL
265 */
266 struct uart_state *state;
267 struct tty_driver *tty_driver;
268};
269
270void uart_write_wakeup(struct uart_port *port);
271
272/*
273 * Baud rate helpers.
274 */
275void uart_update_timeout(struct uart_port *port, unsigned int cflag,
276 unsigned int baud);
606d099c
AC
277unsigned int uart_get_baud_rate(struct uart_port *port, struct ktermios *termios,
278 struct ktermios *old, unsigned int min,
1da177e4
LT
279 unsigned int max);
280unsigned int uart_get_divisor(struct uart_port *port, unsigned int baud);
281
54381067
AV
282/* Base timer interval for polling */
283static inline int uart_poll_timeout(struct uart_port *port)
284{
285 int timeout = port->timeout;
286
287 return timeout > 6 ? (timeout / 2 - 2) : 1;
288}
289
1da177e4
LT
290/*
291 * Console helpers.
292 */
9aac5887
RH
293struct earlycon_device {
294 struct console *con;
295 struct uart_port port;
296 char options[16]; /* e.g., 115200n8 */
297 unsigned int baud;
298};
299int setup_earlycon(char *buf, const char *match,
300 int (*setup)(struct earlycon_device *, const char *));
301
b0b6abd3
RH
302extern int of_setup_earlycon(unsigned long addr,
303 int (*setup)(struct earlycon_device *, const char *));
304
9aac5887
RH
305#define EARLYCON_DECLARE(name, func) \
306static int __init name ## _setup_earlycon(char *buf) \
307{ \
308 return setup_earlycon(buf, __stringify(name), func); \
309} \
310early_param("earlycon", name ## _setup_earlycon);
311
b0b6abd3
RH
312#define OF_EARLYCON_DECLARE(name, compat, fn) \
313 _OF_DECLARE(earlycon, name, compat, fn, void *)
314
1da177e4
LT
315struct uart_port *uart_get_console(struct uart_port *ports, int nr,
316 struct console *c);
317void uart_parse_options(char *options, int *baud, int *parity, int *bits,
318 int *flow);
319int uart_set_options(struct uart_port *port, struct console *co, int baud,
320 int parity, int bits, int flow);
321struct tty_driver *uart_console_device(struct console *co, int *index);
d358788f
RK
322void uart_console_write(struct uart_port *port, const char *s,
323 unsigned int count,
324 void (*putchar)(struct uart_port *, int));
1da177e4
LT
325
326/*
327 * Port/driver registration/removal
328 */
329int uart_register_driver(struct uart_driver *uart);
330void uart_unregister_driver(struct uart_driver *uart);
1da177e4
LT
331int uart_add_one_port(struct uart_driver *reg, struct uart_port *port);
332int uart_remove_one_port(struct uart_driver *reg, struct uart_port *port);
333int uart_match_port(struct uart_port *port1, struct uart_port *port2);
334
335/*
336 * Power Management
337 */
338int uart_suspend_port(struct uart_driver *reg, struct uart_port *port);
339int uart_resume_port(struct uart_driver *reg, struct uart_port *port);
340
341#define uart_circ_empty(circ) ((circ)->head == (circ)->tail)
342#define uart_circ_clear(circ) ((circ)->head = (circ)->tail = 0)
343
344#define uart_circ_chars_pending(circ) \
345 (CIRC_CNT((circ)->head, (circ)->tail, UART_XMIT_SIZE))
346
347#define uart_circ_chars_free(circ) \
348 (CIRC_SPACE((circ)->head, (circ)->tail, UART_XMIT_SIZE))
349
f751928e
AC
350static inline int uart_tx_stopped(struct uart_port *port)
351{
ebd2c8f6 352 struct tty_struct *tty = port->state->port.tty;
f751928e
AC
353 if(tty->stopped || tty->hw_stopped)
354 return 1;
355 return 0;
356}
1da177e4
LT
357
358/*
359 * The following are helper functions for the low level drivers.
360 */
027d7dac
JS
361
362extern void uart_handle_dcd_change(struct uart_port *uport,
363 unsigned int status);
364extern void uart_handle_cts_change(struct uart_port *uport,
365 unsigned int status);
366
367extern void uart_insert_char(struct uart_port *port, unsigned int status,
368 unsigned int overrun, unsigned int ch, unsigned int flag);
369
370#ifdef SUPPORT_SYSRQ
1da177e4 371static inline int
7d12e780 372uart_handle_sysrq_char(struct uart_port *port, unsigned int ch)
1da177e4
LT
373{
374 if (port->sysrq) {
375 if (ch && time_before(jiffies, port->sysrq)) {
f335397d 376 handle_sysrq(ch);
1da177e4
LT
377 port->sysrq = 0;
378 return 1;
379 }
380 port->sysrq = 0;
381 }
382 return 0;
383}
027d7dac
JS
384#else
385#define uart_handle_sysrq_char(port,ch) ({ (void)port; 0; })
4e149184 386#endif
1da177e4
LT
387
388/*
389 * We do the SysRQ and SAK checking like this...
390 */
391static inline int uart_handle_break(struct uart_port *port)
392{
ebd2c8f6 393 struct uart_state *state = port->state;
bf03f65b
DW
394
395 if (port->handle_break)
396 port->handle_break(port);
397
1da177e4
LT
398#ifdef SUPPORT_SYSRQ
399 if (port->cons && port->cons->index == port->line) {
400 if (!port->sysrq) {
401 port->sysrq = jiffies + HZ*5;
402 return 1;
403 }
404 port->sysrq = 0;
405 }
406#endif
27ae7a74 407 if (port->flags & UPF_SAK)
ebd2c8f6 408 do_SAK(state->port.tty);
1da177e4
LT
409 return 0;
410}
411
1da177e4
LT
412/*
413 * UART_ENABLE_MS - determine if port should enable modem status irqs
414 */
415#define UART_ENABLE_MS(port,cflag) ((port)->flags & UPF_HARDPPS_CD || \
416 (cflag) & CRTSCTS || \
417 !((cflag) & CLOCAL))
418
1da177e4 419#endif /* LINUX_SERIAL_CORE_H */
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