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 23 24#include <linux/compiler.h> 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> 30#include <linux/mutex.h> 31#include <linux/sysrq.h> 32#include <uapi/linux/serial_core.h> 33 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 41struct uart_port; 42struct serial_struct; 43struct device; 44 45/* 46 * This structure describes all the operations that can be done on the 47 * physical hardware. See Documentation/serial/driver for details. 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 *); 53 void (*stop_tx)(struct uart_port *); 54 void (*start_tx)(struct uart_port *); 55 void (*throttle)(struct uart_port *); 56 void (*unthrottle)(struct uart_port *); 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 *); 63 void (*flush_buffer)(struct uart_port *); 64 void (*set_termios)(struct uart_port *, struct ktermios *new, 65 struct ktermios *old); 66 void (*set_ldisc)(struct uart_port *, struct ktermios *); 67 void (*pm)(struct uart_port *, unsigned int state, 68 unsigned int oldstate); 69 70 /* 71 * Return a string describing the type of the port 72 */ 73 const char *(*type)(struct uart_port *); 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); 89#ifdef CONFIG_CONSOLE_POLL 90 int (*poll_init)(struct uart_port *); 91 void (*poll_put_char)(struct uart_port *, unsigned char); 92 int (*poll_get_char)(struct uart_port *); 93#endif 94}; 95 96#define NO_POLL_CHAR 0x00ff0000 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 114typedef unsigned int __bitwise__ upf_t; 115typedef unsigned int __bitwise__ upstat_t; 116 117struct uart_port { 118 spinlock_t lock; /* port lock */ 119 unsigned long iobase; /* in/out[bwl] */ 120 unsigned char __iomem *membase; /* read/write[bwl] */ 121 unsigned int (*serial_in)(struct uart_port *, int); 122 void (*serial_out)(struct uart_port *, int, int); 123 void (*set_termios)(struct uart_port *, 124 struct ktermios *new, 125 struct ktermios *old); 126 void (*set_mctrl)(struct uart_port *, unsigned int); 127 int (*startup)(struct uart_port *port); 128 void (*shutdown)(struct uart_port *port); 129 void (*throttle)(struct uart_port *port); 130 void (*unthrottle)(struct uart_port *port); 131 int (*handle_irq)(struct uart_port *); 132 void (*pm)(struct uart_port *, unsigned int state, 133 unsigned int old); 134 void (*handle_break)(struct uart_port *); 135 int (*rs485_config)(struct uart_port *, 136 struct serial_rs485 *rs485); 137 unsigned int irq; /* irq number */ 138 unsigned long irqflags; /* irq flags */ 139 unsigned int uartclk; /* base uart clock */ 140 unsigned int fifosize; /* tx fifo size */ 141 unsigned char x_char; /* xon/xoff char */ 142 unsigned char regshift; /* reg offset shift */ 143 unsigned char iotype; /* io access style */ 144 unsigned char unused1; 145 146#define UPIO_PORT (SERIAL_IO_PORT) /* 8b I/O port access */ 147#define UPIO_HUB6 (SERIAL_IO_HUB6) /* Hub6 ISA card */ 148#define UPIO_MEM (SERIAL_IO_MEM) /* 8b MMIO access */ 149#define UPIO_MEM32 (SERIAL_IO_MEM32) /* 32b little endian */ 150#define UPIO_AU (SERIAL_IO_AU) /* Au1x00 and RT288x type IO */ 151#define UPIO_TSI (SERIAL_IO_TSI) /* Tsi108/109 type IO */ 152#define UPIO_MEM32BE (SERIAL_IO_MEM32BE) /* 32b big endian */ 153 154 unsigned int read_status_mask; /* driver specific */ 155 unsigned int ignore_status_mask; /* driver specific */ 156 struct uart_state *state; /* pointer to parent state */ 157 struct uart_icount icount; /* statistics */ 158 159 struct console *cons; /* struct console, if any */ 160#if defined(CONFIG_SERIAL_CORE_CONSOLE) || defined(SUPPORT_SYSRQ) 161 unsigned long sysrq; /* sysrq timeout */ 162#endif 163 164 /* flags must be updated while holding port mutex */ 165 upf_t flags; 166 167 /* 168 * These flags must be equivalent to the flags defined in 169 * include/uapi/linux/tty_flags.h which are the userspace definitions 170 * assigned from the serial_struct flags in uart_set_info() 171 * [for bit definitions in the UPF_CHANGE_MASK] 172 * 173 * Bits [0..UPF_LAST_USER] are userspace defined/visible/changeable 174 * except bit 15 (UPF_NO_TXEN_TEST) which is masked off. 175 * The remaining bits are serial-core specific and not modifiable by 176 * userspace. 177 */ 178#define UPF_FOURPORT ((__force upf_t) ASYNC_FOURPORT /* 1 */ ) 179#define UPF_SAK ((__force upf_t) ASYNC_SAK /* 2 */ ) 180#define UPF_SPD_HI ((__force upf_t) ASYNC_SPD_HI /* 4 */ ) 181#define UPF_SPD_VHI ((__force upf_t) ASYNC_SPD_VHI /* 5 */ ) 182#define UPF_SPD_CUST ((__force upf_t) ASYNC_SPD_CUST /* 0x0030 */ ) 183#define UPF_SPD_WARP ((__force upf_t) ASYNC_SPD_WARP /* 0x1010 */ ) 184#define UPF_SPD_MASK ((__force upf_t) ASYNC_SPD_MASK /* 0x1030 */ ) 185#define UPF_SKIP_TEST ((__force upf_t) ASYNC_SKIP_TEST /* 6 */ ) 186#define UPF_AUTO_IRQ ((__force upf_t) ASYNC_AUTO_IRQ /* 7 */ ) 187#define UPF_HARDPPS_CD ((__force upf_t) ASYNC_HARDPPS_CD /* 11 */ ) 188#define UPF_SPD_SHI ((__force upf_t) ASYNC_SPD_SHI /* 12 */ ) 189#define UPF_LOW_LATENCY ((__force upf_t) ASYNC_LOW_LATENCY /* 13 */ ) 190#define UPF_BUGGY_UART ((__force upf_t) ASYNC_BUGGY_UART /* 14 */ ) 191#define UPF_NO_TXEN_TEST ((__force upf_t) (1 << 15)) 192#define UPF_MAGIC_MULTIPLIER ((__force upf_t) ASYNC_MAGIC_MULTIPLIER /* 16 */ ) 193 194/* Port has hardware-assisted h/w flow control */ 195#define UPF_AUTO_CTS ((__force upf_t) (1 << 20)) 196#define UPF_AUTO_RTS ((__force upf_t) (1 << 21)) 197#define UPF_HARD_FLOW ((__force upf_t) (UPF_AUTO_CTS | UPF_AUTO_RTS)) 198/* Port has hardware-assisted s/w flow control */ 199#define UPF_SOFT_FLOW ((__force upf_t) (1 << 22)) 200#define UPF_CONS_FLOW ((__force upf_t) (1 << 23)) 201#define UPF_SHARE_IRQ ((__force upf_t) (1 << 24)) 202#define UPF_EXAR_EFR ((__force upf_t) (1 << 25)) 203#define UPF_BUG_THRE ((__force upf_t) (1 << 26)) 204/* The exact UART type is known and should not be probed. */ 205#define UPF_FIXED_TYPE ((__force upf_t) (1 << 27)) 206#define UPF_BOOT_AUTOCONF ((__force upf_t) (1 << 28)) 207#define UPF_FIXED_PORT ((__force upf_t) (1 << 29)) 208#define UPF_DEAD ((__force upf_t) (1 << 30)) 209#define UPF_IOREMAP ((__force upf_t) (1 << 31)) 210 211#define __UPF_CHANGE_MASK 0x17fff 212#define UPF_CHANGE_MASK ((__force upf_t) __UPF_CHANGE_MASK) 213#define UPF_USR_MASK ((__force upf_t) (UPF_SPD_MASK|UPF_LOW_LATENCY)) 214 215#if __UPF_CHANGE_MASK > ASYNC_FLAGS 216#error Change mask not equivalent to userspace-visible bit defines 217#endif 218 219 /* 220 * Must hold termios_rwsem, port mutex and port lock to change; 221 * can hold any one lock to read. 222 */ 223 upstat_t status; 224 225#define UPSTAT_CTS_ENABLE ((__force upstat_t) (1 << 0)) 226#define UPSTAT_DCD_ENABLE ((__force upstat_t) (1 << 1)) 227#define UPSTAT_AUTORTS ((__force upstat_t) (1 << 2)) 228#define UPSTAT_AUTOCTS ((__force upstat_t) (1 << 3)) 229#define UPSTAT_AUTOXOFF ((__force upstat_t) (1 << 4)) 230 231 int hw_stopped; /* sw-assisted CTS flow state */ 232 unsigned int mctrl; /* current modem ctrl settings */ 233 unsigned int timeout; /* character-based timeout */ 234 unsigned int type; /* port type */ 235 const struct uart_ops *ops; 236 unsigned int custom_divisor; 237 unsigned int line; /* port index */ 238 unsigned int minor; 239 resource_size_t mapbase; /* for ioremap */ 240 resource_size_t mapsize; 241 struct device *dev; /* parent device */ 242 unsigned char hub6; /* this should be in the 8250 driver */ 243 unsigned char suspended; 244 unsigned char irq_wake; 245 unsigned char unused[2]; 246 struct attribute_group *attr_group; /* port specific attributes */ 247 const struct attribute_group **tty_groups; /* all attributes (serial core use only) */ 248 struct serial_rs485 rs485; 249 void *private_data; /* generic platform data pointer */ 250}; 251 252static inline int serial_port_in(struct uart_port *up, int offset) 253{ 254 return up->serial_in(up, offset); 255} 256 257static inline void serial_port_out(struct uart_port *up, int offset, int value) 258{ 259 up->serial_out(up, offset, value); 260} 261 262/** 263 * enum uart_pm_state - power states for UARTs 264 * @UART_PM_STATE_ON: UART is powered, up and operational 265 * @UART_PM_STATE_OFF: UART is powered off 266 * @UART_PM_STATE_UNDEFINED: sentinel 267 */ 268enum uart_pm_state { 269 UART_PM_STATE_ON = 0, 270 UART_PM_STATE_OFF = 3, /* number taken from ACPI */ 271 UART_PM_STATE_UNDEFINED, 272}; 273 274/* 275 * This is the state information which is persistent across opens. 276 */ 277struct uart_state { 278 struct tty_port port; 279 280 enum uart_pm_state pm_state; 281 struct circ_buf xmit; 282 283 struct uart_port *uart_port; 284}; 285 286#define UART_XMIT_SIZE PAGE_SIZE 287 288 289/* number of characters left in xmit buffer before we ask for more */ 290#define WAKEUP_CHARS 256 291 292struct module; 293struct tty_driver; 294 295struct uart_driver { 296 struct module *owner; 297 const char *driver_name; 298 const char *dev_name; 299 int major; 300 int minor; 301 int nr; 302 struct console *cons; 303 304 /* 305 * these are private; the low level driver should not 306 * touch these; they should be initialised to NULL 307 */ 308 struct uart_state *state; 309 struct tty_driver *tty_driver; 310}; 311 312void uart_write_wakeup(struct uart_port *port); 313 314/* 315 * Baud rate helpers. 316 */ 317void uart_update_timeout(struct uart_port *port, unsigned int cflag, 318 unsigned int baud); 319unsigned int uart_get_baud_rate(struct uart_port *port, struct ktermios *termios, 320 struct ktermios *old, unsigned int min, 321 unsigned int max); 322unsigned int uart_get_divisor(struct uart_port *port, unsigned int baud); 323 324/* Base timer interval for polling */ 325static inline int uart_poll_timeout(struct uart_port *port) 326{ 327 int timeout = port->timeout; 328 329 return timeout > 6 ? (timeout / 2 - 2) : 1; 330} 331 332/* 333 * Console helpers. 334 */ 335struct earlycon_device { 336 struct console *con; 337 struct uart_port port; 338 char options[16]; /* e.g., 115200n8 */ 339 unsigned int baud; 340}; 341 342struct earlycon_id { 343 char name[16]; 344 int (*setup)(struct earlycon_device *, const char *options); 345} __aligned(32); 346 347extern int setup_earlycon(char *buf); 348extern int of_setup_earlycon(unsigned long addr, 349 int (*setup)(struct earlycon_device *, const char *)); 350 351#define EARLYCON_DECLARE(_name, func) \ 352 static const struct earlycon_id __earlycon_##_name \ 353 __used __section(__earlycon_table) \ 354 = { .name = __stringify(_name), \ 355 .setup = func } 356 357#define OF_EARLYCON_DECLARE(name, compat, fn) \ 358 _OF_DECLARE(earlycon, name, compat, fn, void *) 359 360struct uart_port *uart_get_console(struct uart_port *ports, int nr, 361 struct console *c); 362int uart_parse_earlycon(char *p, unsigned char *iotype, unsigned long *addr, 363 char **options); 364void uart_parse_options(char *options, int *baud, int *parity, int *bits, 365 int *flow); 366int uart_set_options(struct uart_port *port, struct console *co, int baud, 367 int parity, int bits, int flow); 368struct tty_driver *uart_console_device(struct console *co, int *index); 369void uart_console_write(struct uart_port *port, const char *s, 370 unsigned int count, 371 void (*putchar)(struct uart_port *, int)); 372 373/* 374 * Port/driver registration/removal 375 */ 376int uart_register_driver(struct uart_driver *uart); 377void uart_unregister_driver(struct uart_driver *uart); 378int uart_add_one_port(struct uart_driver *reg, struct uart_port *port); 379int uart_remove_one_port(struct uart_driver *reg, struct uart_port *port); 380int uart_match_port(struct uart_port *port1, struct uart_port *port2); 381 382/* 383 * Power Management 384 */ 385int uart_suspend_port(struct uart_driver *reg, struct uart_port *port); 386int uart_resume_port(struct uart_driver *reg, struct uart_port *port); 387 388#define uart_circ_empty(circ) ((circ)->head == (circ)->tail) 389#define uart_circ_clear(circ) ((circ)->head = (circ)->tail = 0) 390 391#define uart_circ_chars_pending(circ) \ 392 (CIRC_CNT((circ)->head, (circ)->tail, UART_XMIT_SIZE)) 393 394#define uart_circ_chars_free(circ) \ 395 (CIRC_SPACE((circ)->head, (circ)->tail, UART_XMIT_SIZE)) 396 397static inline int uart_tx_stopped(struct uart_port *port) 398{ 399 struct tty_struct *tty = port->state->port.tty; 400 if (tty->stopped || port->hw_stopped) 401 return 1; 402 return 0; 403} 404 405static inline bool uart_cts_enabled(struct uart_port *uport) 406{ 407 return !!(uport->status & UPSTAT_CTS_ENABLE); 408} 409 410static inline bool uart_softcts_mode(struct uart_port *uport) 411{ 412 upstat_t mask = UPSTAT_CTS_ENABLE | UPSTAT_AUTOCTS; 413 414 return ((uport->status & mask) == UPSTAT_CTS_ENABLE); 415} 416 417/* 418 * The following are helper functions for the low level drivers. 419 */ 420 421extern void uart_handle_dcd_change(struct uart_port *uport, 422 unsigned int status); 423extern void uart_handle_cts_change(struct uart_port *uport, 424 unsigned int status); 425 426extern void uart_insert_char(struct uart_port *port, unsigned int status, 427 unsigned int overrun, unsigned int ch, unsigned int flag); 428 429#ifdef SUPPORT_SYSRQ 430static inline int 431uart_handle_sysrq_char(struct uart_port *port, unsigned int ch) 432{ 433 if (port->sysrq) { 434 if (ch && time_before(jiffies, port->sysrq)) { 435 handle_sysrq(ch); 436 port->sysrq = 0; 437 return 1; 438 } 439 port->sysrq = 0; 440 } 441 return 0; 442} 443#else 444#define uart_handle_sysrq_char(port,ch) ({ (void)port; 0; }) 445#endif 446 447/* 448 * We do the SysRQ and SAK checking like this... 449 */ 450static inline int uart_handle_break(struct uart_port *port) 451{ 452 struct uart_state *state = port->state; 453 454 if (port->handle_break) 455 port->handle_break(port); 456 457#ifdef SUPPORT_SYSRQ 458 if (port->cons && port->cons->index == port->line) { 459 if (!port->sysrq) { 460 port->sysrq = jiffies + HZ*5; 461 return 1; 462 } 463 port->sysrq = 0; 464 } 465#endif 466 if (port->flags & UPF_SAK) 467 do_SAK(state->port.tty); 468 return 0; 469} 470 471/* 472 * UART_ENABLE_MS - determine if port should enable modem status irqs 473 */ 474#define UART_ENABLE_MS(port,cflag) ((port)->flags & UPF_HARDPPS_CD || \ 475 (cflag) & CRTSCTS || \ 476 !((cflag) & CLOCAL)) 477 478#endif /* LINUX_SERIAL_CORE_H */ 479