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 #include <linux/bitops.h> 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) ({ (void)port; 0; }) 39 #endif 40 41 struct uart_port; 42 struct serial_struct; 43 struct 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 */ 49 struct 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) 99 100 struct 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 }; 113 114 typedef unsigned int __bitwise upf_t; 115 typedef unsigned int __bitwise upstat_t; 116 117 struct 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_ldisc)(struct uart_port *, 127 struct ktermios *); 128 unsigned int (*get_mctrl)(struct uart_port *); 129 void (*set_mctrl)(struct uart_port *, unsigned int); 130 unsigned int (*get_divisor)(struct uart_port *, 131 unsigned int baud, 132 unsigned int *frac); 133 void (*set_divisor)(struct uart_port *, 134 unsigned int baud, 135 unsigned int quot, 136 unsigned int quot_frac); 137 int (*startup)(struct uart_port *port); 138 void (*shutdown)(struct uart_port *port); 139 void (*throttle)(struct uart_port *port); 140 void (*unthrottle)(struct uart_port *port); 141 int (*handle_irq)(struct uart_port *); 142 void (*pm)(struct uart_port *, unsigned int state, 143 unsigned int old); 144 void (*handle_break)(struct uart_port *); 145 int (*rs485_config)(struct uart_port *, 146 struct serial_rs485 *rs485); 147 int (*iso7816_config)(struct uart_port *, 148 struct serial_iso7816 *iso7816); 149 unsigned int irq; /* irq number */ 150 unsigned long irqflags; /* irq flags */ 151 unsigned int uartclk; /* base uart clock */ 152 unsigned int fifosize; /* tx fifo size */ 153 unsigned char x_char; /* xon/xoff char */ 154 unsigned char regshift; /* reg offset shift */ 155 unsigned char iotype; /* io access style */ 156 unsigned char quirks; /* internal quirks */ 157 158 #define UPIO_PORT (SERIAL_IO_PORT) /* 8b I/O port access */ 159 #define UPIO_HUB6 (SERIAL_IO_HUB6) /* Hub6 ISA card */ 160 #define UPIO_MEM (SERIAL_IO_MEM) /* driver-specific */ 161 #define UPIO_MEM32 (SERIAL_IO_MEM32) /* 32b little endian */ 162 #define UPIO_AU (SERIAL_IO_AU) /* Au1x00 and RT288x type IO */ 163 #define UPIO_TSI (SERIAL_IO_TSI) /* Tsi108/109 type IO */ 164 #define UPIO_MEM32BE (SERIAL_IO_MEM32BE) /* 32b big endian */ 165 #define UPIO_MEM16 (SERIAL_IO_MEM16) /* 16b little endian */ 166 167 /* quirks must be updated while holding port mutex */ 168 #define UPQ_NO_TXEN_TEST BIT(0) 169 170 unsigned int read_status_mask; /* driver specific */ 171 unsigned int ignore_status_mask; /* driver specific */ 172 struct uart_state *state; /* pointer to parent state */ 173 struct uart_icount icount; /* statistics */ 174 175 struct console *cons; /* struct console, if any */ 176 #if defined(CONFIG_SERIAL_CORE_CONSOLE) || defined(SUPPORT_SYSRQ) 177 unsigned long sysrq; /* sysrq timeout */ 178 #endif 179 180 /* flags must be updated while holding port mutex */ 181 upf_t flags; 182 183 /* 184 * These flags must be equivalent to the flags defined in 185 * include/uapi/linux/tty_flags.h which are the userspace definitions 186 * assigned from the serial_struct flags in uart_set_info() 187 * [for bit definitions in the UPF_CHANGE_MASK] 188 * 189 * Bits [0..UPF_LAST_USER] are userspace defined/visible/changeable 190 * The remaining bits are serial-core specific and not modifiable by 191 * userspace. 192 */ 193 #define UPF_FOURPORT ((__force upf_t) ASYNC_FOURPORT /* 1 */ ) 194 #define UPF_SAK ((__force upf_t) ASYNC_SAK /* 2 */ ) 195 #define UPF_SPD_HI ((__force upf_t) ASYNC_SPD_HI /* 4 */ ) 196 #define UPF_SPD_VHI ((__force upf_t) ASYNC_SPD_VHI /* 5 */ ) 197 #define UPF_SPD_CUST ((__force upf_t) ASYNC_SPD_CUST /* 0x0030 */ ) 198 #define UPF_SPD_WARP ((__force upf_t) ASYNC_SPD_WARP /* 0x1010 */ ) 199 #define UPF_SPD_MASK ((__force upf_t) ASYNC_SPD_MASK /* 0x1030 */ ) 200 #define UPF_SKIP_TEST ((__force upf_t) ASYNC_SKIP_TEST /* 6 */ ) 201 #define UPF_AUTO_IRQ ((__force upf_t) ASYNC_AUTO_IRQ /* 7 */ ) 202 #define UPF_HARDPPS_CD ((__force upf_t) ASYNC_HARDPPS_CD /* 11 */ ) 203 #define UPF_SPD_SHI ((__force upf_t) ASYNC_SPD_SHI /* 12 */ ) 204 #define UPF_LOW_LATENCY ((__force upf_t) ASYNC_LOW_LATENCY /* 13 */ ) 205 #define UPF_BUGGY_UART ((__force upf_t) ASYNC_BUGGY_UART /* 14 */ ) 206 #define UPF_MAGIC_MULTIPLIER ((__force upf_t) ASYNC_MAGIC_MULTIPLIER /* 16 */ ) 207 208 #define UPF_NO_THRE_TEST ((__force upf_t) (1 << 19)) 209 /* Port has hardware-assisted h/w flow control */ 210 #define UPF_AUTO_CTS ((__force upf_t) (1 << 20)) 211 #define UPF_AUTO_RTS ((__force upf_t) (1 << 21)) 212 #define UPF_HARD_FLOW ((__force upf_t) (UPF_AUTO_CTS | UPF_AUTO_RTS)) 213 /* Port has hardware-assisted s/w flow control */ 214 #define UPF_SOFT_FLOW ((__force upf_t) (1 << 22)) 215 #define UPF_CONS_FLOW ((__force upf_t) (1 << 23)) 216 #define UPF_SHARE_IRQ ((__force upf_t) (1 << 24)) 217 #define UPF_EXAR_EFR ((__force upf_t) (1 << 25)) 218 #define UPF_BUG_THRE ((__force upf_t) (1 << 26)) 219 /* The exact UART type is known and should not be probed. */ 220 #define UPF_FIXED_TYPE ((__force upf_t) (1 << 27)) 221 #define UPF_BOOT_AUTOCONF ((__force upf_t) (1 << 28)) 222 #define UPF_FIXED_PORT ((__force upf_t) (1 << 29)) 223 #define UPF_DEAD ((__force upf_t) (1 << 30)) 224 #define UPF_IOREMAP ((__force upf_t) (1 << 31)) 225 226 #define __UPF_CHANGE_MASK 0x17fff 227 #define UPF_CHANGE_MASK ((__force upf_t) __UPF_CHANGE_MASK) 228 #define UPF_USR_MASK ((__force upf_t) (UPF_SPD_MASK|UPF_LOW_LATENCY)) 229 230 #if __UPF_CHANGE_MASK > ASYNC_FLAGS 231 #error Change mask not equivalent to userspace-visible bit defines 232 #endif 233 234 /* 235 * Must hold termios_rwsem, port mutex and port lock to change; 236 * can hold any one lock to read. 237 */ 238 upstat_t status; 239 240 #define UPSTAT_CTS_ENABLE ((__force upstat_t) (1 << 0)) 241 #define UPSTAT_DCD_ENABLE ((__force upstat_t) (1 << 1)) 242 #define UPSTAT_AUTORTS ((__force upstat_t) (1 << 2)) 243 #define UPSTAT_AUTOCTS ((__force upstat_t) (1 << 3)) 244 #define UPSTAT_AUTOXOFF ((__force upstat_t) (1 << 4)) 245 #define UPSTAT_SYNC_FIFO ((__force upstat_t) (1 << 5)) 246 247 int hw_stopped; /* sw-assisted CTS flow state */ 248 unsigned int mctrl; /* current modem ctrl settings */ 249 unsigned int timeout; /* character-based timeout */ 250 unsigned int type; /* port type */ 251 const struct uart_ops *ops; 252 unsigned int custom_divisor; 253 unsigned int line; /* port index */ 254 unsigned int minor; 255 resource_size_t mapbase; /* for ioremap */ 256 resource_size_t mapsize; 257 struct device *dev; /* parent device */ 258 unsigned char hub6; /* this should be in the 8250 driver */ 259 unsigned char suspended; 260 unsigned char unused[2]; 261 const char *name; /* port name */ 262 struct attribute_group *attr_group; /* port specific attributes */ 263 const struct attribute_group **tty_groups; /* all attributes (serial core use only) */ 264 struct serial_rs485 rs485; 265 struct serial_iso7816 iso7816; 266 void *private_data; /* generic platform data pointer */ 267 }; 268 269 static inline int serial_port_in(struct uart_port *up, int offset) 270 { 271 return up->serial_in(up, offset); 272 } 273 274 static inline void serial_port_out(struct uart_port *up, int offset, int value) 275 { 276 up->serial_out(up, offset, value); 277 } 278 279 /** 280 * enum uart_pm_state - power states for UARTs 281 * @UART_PM_STATE_ON: UART is powered, up and operational 282 * @UART_PM_STATE_OFF: UART is powered off 283 * @UART_PM_STATE_UNDEFINED: sentinel 284 */ 285 enum uart_pm_state { 286 UART_PM_STATE_ON = 0, 287 UART_PM_STATE_OFF = 3, /* number taken from ACPI */ 288 UART_PM_STATE_UNDEFINED, 289 }; 290 291 /* 292 * This is the state information which is persistent across opens. 293 */ 294 struct uart_state { 295 struct tty_port port; 296 297 enum uart_pm_state pm_state; 298 struct circ_buf xmit; 299 300 atomic_t refcount; 301 wait_queue_head_t remove_wait; 302 struct uart_port *uart_port; 303 }; 304 305 #define UART_XMIT_SIZE PAGE_SIZE 306 307 308 /* number of characters left in xmit buffer before we ask for more */ 309 #define WAKEUP_CHARS 256 310 311 struct module; 312 struct tty_driver; 313 314 struct uart_driver { 315 struct module *owner; 316 const char *driver_name; 317 const char *dev_name; 318 int major; 319 int minor; 320 int nr; 321 struct console *cons; 322 323 /* 324 * these are private; the low level driver should not 325 * touch these; they should be initialised to NULL 326 */ 327 struct uart_state *state; 328 struct tty_driver *tty_driver; 329 }; 330 331 void uart_write_wakeup(struct uart_port *port); 332 333 /* 334 * Baud rate helpers. 335 */ 336 void uart_update_timeout(struct uart_port *port, unsigned int cflag, 337 unsigned int baud); 338 unsigned int uart_get_baud_rate(struct uart_port *port, struct ktermios *termios, 339 struct ktermios *old, unsigned int min, 340 unsigned int max); 341 unsigned int uart_get_divisor(struct uart_port *port, unsigned int baud); 342 343 /* Base timer interval for polling */ 344 static inline int uart_poll_timeout(struct uart_port *port) 345 { 346 int timeout = port->timeout; 347 348 return timeout > 6 ? (timeout / 2 - 2) : 1; 349 } 350 351 /* 352 * Console helpers. 353 */ 354 struct earlycon_device { 355 struct console *con; 356 struct uart_port port; 357 char options[16]; /* e.g., 115200n8 */ 358 unsigned int baud; 359 }; 360 361 struct earlycon_id { 362 char name[15]; 363 char name_term; /* In case compiler didn't '\0' term name */ 364 char compatible[128]; 365 int (*setup)(struct earlycon_device *, const char *options); 366 }; 367 368 extern const struct earlycon_id *__earlycon_table[]; 369 extern const struct earlycon_id *__earlycon_table_end[]; 370 371 #if defined(CONFIG_SERIAL_EARLYCON) && !defined(MODULE) 372 #define EARLYCON_USED_OR_UNUSED __used 373 #else 374 #define EARLYCON_USED_OR_UNUSED __maybe_unused 375 #endif 376 377 #define _OF_EARLYCON_DECLARE(_name, compat, fn, unique_id) \ 378 static const struct earlycon_id unique_id \ 379 EARLYCON_USED_OR_UNUSED __initconst \ 380 = { .name = __stringify(_name), \ 381 .compatible = compat, \ 382 .setup = fn }; \ 383 static const struct earlycon_id EARLYCON_USED_OR_UNUSED \ 384 __section(__earlycon_table) \ 385 * const __PASTE(__p, unique_id) = &unique_id 386 387 #define OF_EARLYCON_DECLARE(_name, compat, fn) \ 388 _OF_EARLYCON_DECLARE(_name, compat, fn, \ 389 __UNIQUE_ID(__earlycon_##_name)) 390 391 #define EARLYCON_DECLARE(_name, fn) OF_EARLYCON_DECLARE(_name, "", fn) 392 393 extern int of_setup_earlycon(const struct earlycon_id *match, 394 unsigned long node, 395 const char *options); 396 397 #ifdef CONFIG_SERIAL_EARLYCON 398 extern bool earlycon_acpi_spcr_enable __initdata; 399 int setup_earlycon(char *buf); 400 #else 401 static const bool earlycon_acpi_spcr_enable EARLYCON_USED_OR_UNUSED; 402 static inline int setup_earlycon(char *buf) { return 0; } 403 #endif 404 405 struct uart_port *uart_get_console(struct uart_port *ports, int nr, 406 struct console *c); 407 int uart_parse_earlycon(char *p, unsigned char *iotype, resource_size_t *addr, 408 char **options); 409 void uart_parse_options(const char *options, int *baud, int *parity, int *bits, 410 int *flow); 411 int uart_set_options(struct uart_port *port, struct console *co, int baud, 412 int parity, int bits, int flow); 413 struct tty_driver *uart_console_device(struct console *co, int *index); 414 void uart_console_write(struct uart_port *port, const char *s, 415 unsigned int count, 416 void (*putchar)(struct uart_port *, int)); 417 418 /* 419 * Port/driver registration/removal 420 */ 421 int uart_register_driver(struct uart_driver *uart); 422 void uart_unregister_driver(struct uart_driver *uart); 423 int uart_add_one_port(struct uart_driver *reg, struct uart_port *port); 424 int uart_remove_one_port(struct uart_driver *reg, struct uart_port *port); 425 int uart_match_port(struct uart_port *port1, struct uart_port *port2); 426 427 /* 428 * Power Management 429 */ 430 int uart_suspend_port(struct uart_driver *reg, struct uart_port *port); 431 int uart_resume_port(struct uart_driver *reg, struct uart_port *port); 432 433 #define uart_circ_empty(circ) ((circ)->head == (circ)->tail) 434 #define uart_circ_clear(circ) ((circ)->head = (circ)->tail = 0) 435 436 #define uart_circ_chars_pending(circ) \ 437 (CIRC_CNT((circ)->head, (circ)->tail, UART_XMIT_SIZE)) 438 439 #define uart_circ_chars_free(circ) \ 440 (CIRC_SPACE((circ)->head, (circ)->tail, UART_XMIT_SIZE)) 441 442 static inline int uart_tx_stopped(struct uart_port *port) 443 { 444 struct tty_struct *tty = port->state->port.tty; 445 if ((tty && tty->stopped) || port->hw_stopped) 446 return 1; 447 return 0; 448 } 449 450 static inline bool uart_cts_enabled(struct uart_port *uport) 451 { 452 return !!(uport->status & UPSTAT_CTS_ENABLE); 453 } 454 455 static inline bool uart_softcts_mode(struct uart_port *uport) 456 { 457 upstat_t mask = UPSTAT_CTS_ENABLE | UPSTAT_AUTOCTS; 458 459 return ((uport->status & mask) == UPSTAT_CTS_ENABLE); 460 } 461 462 /* 463 * The following are helper functions for the low level drivers. 464 */ 465 466 extern void uart_handle_dcd_change(struct uart_port *uport, 467 unsigned int status); 468 extern void uart_handle_cts_change(struct uart_port *uport, 469 unsigned int status); 470 471 extern void uart_insert_char(struct uart_port *port, unsigned int status, 472 unsigned int overrun, unsigned int ch, unsigned int flag); 473 474 #if defined(SUPPORT_SYSRQ) && defined(CONFIG_MAGIC_SYSRQ_SERIAL) 475 static inline int 476 uart_handle_sysrq_char(struct uart_port *port, unsigned int ch) 477 { 478 if (port->sysrq) { 479 if (ch && time_before(jiffies, port->sysrq)) { 480 handle_sysrq(ch); 481 port->sysrq = 0; 482 return 1; 483 } 484 port->sysrq = 0; 485 } 486 return 0; 487 } 488 #else 489 #define uart_handle_sysrq_char(port,ch) ({ (void)port; 0; }) 490 #endif 491 492 /* 493 * We do the SysRQ and SAK checking like this... 494 */ 495 static inline int uart_handle_break(struct uart_port *port) 496 { 497 struct uart_state *state = port->state; 498 499 if (port->handle_break) 500 port->handle_break(port); 501 502 #ifdef SUPPORT_SYSRQ 503 if (port->cons && port->cons->index == port->line) { 504 if (!port->sysrq) { 505 port->sysrq = jiffies + HZ*5; 506 return 1; 507 } 508 port->sysrq = 0; 509 } 510 #endif 511 if (port->flags & UPF_SAK) 512 do_SAK(state->port.tty); 513 return 0; 514 } 515 516 /* 517 * UART_ENABLE_MS - determine if port should enable modem status irqs 518 */ 519 #define UART_ENABLE_MS(port,cflag) ((port)->flags & UPF_HARDPPS_CD || \ 520 (cflag) & CRTSCTS || \ 521 !((cflag) & CLOCAL)) 522 523 void uart_get_rs485_mode(struct device *dev, struct serial_rs485 *rs485conf); 524 #endif /* LINUX_SERIAL_CORE_H */ 525