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 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_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 resource_size_t mapbase; /* for ioremap */ 239 struct device *dev; /* parent device */ 240 unsigned char hub6; /* this should be in the 8250 driver */ 241 unsigned char suspended; 242 unsigned char irq_wake; 243 unsigned char unused[2]; 244 struct attribute_group *attr_group; /* port specific attributes */ 245 const struct attribute_group **tty_groups; /* all attributes (serial core use only) */ 246 struct serial_rs485 rs485; 247 void *private_data; /* generic platform data pointer */ 248 }; 249 250 static inline int serial_port_in(struct uart_port *up, int offset) 251 { 252 return up->serial_in(up, offset); 253 } 254 255 static inline void serial_port_out(struct uart_port *up, int offset, int value) 256 { 257 up->serial_out(up, offset, value); 258 } 259 260 /** 261 * enum uart_pm_state - power states for UARTs 262 * @UART_PM_STATE_ON: UART is powered, up and operational 263 * @UART_PM_STATE_OFF: UART is powered off 264 * @UART_PM_STATE_UNDEFINED: sentinel 265 */ 266 enum uart_pm_state { 267 UART_PM_STATE_ON = 0, 268 UART_PM_STATE_OFF = 3, /* number taken from ACPI */ 269 UART_PM_STATE_UNDEFINED, 270 }; 271 272 /* 273 * This is the state information which is persistent across opens. 274 */ 275 struct uart_state { 276 struct tty_port port; 277 278 enum uart_pm_state pm_state; 279 struct circ_buf xmit; 280 281 struct uart_port *uart_port; 282 }; 283 284 #define UART_XMIT_SIZE PAGE_SIZE 285 286 287 /* number of characters left in xmit buffer before we ask for more */ 288 #define WAKEUP_CHARS 256 289 290 struct module; 291 struct tty_driver; 292 293 struct uart_driver { 294 struct module *owner; 295 const char *driver_name; 296 const char *dev_name; 297 int major; 298 int minor; 299 int nr; 300 struct console *cons; 301 302 /* 303 * these are private; the low level driver should not 304 * touch these; they should be initialised to NULL 305 */ 306 struct uart_state *state; 307 struct tty_driver *tty_driver; 308 }; 309 310 void uart_write_wakeup(struct uart_port *port); 311 312 /* 313 * Baud rate helpers. 314 */ 315 void uart_update_timeout(struct uart_port *port, unsigned int cflag, 316 unsigned int baud); 317 unsigned int uart_get_baud_rate(struct uart_port *port, struct ktermios *termios, 318 struct ktermios *old, unsigned int min, 319 unsigned int max); 320 unsigned int uart_get_divisor(struct uart_port *port, unsigned int baud); 321 322 /* Base timer interval for polling */ 323 static inline int uart_poll_timeout(struct uart_port *port) 324 { 325 int timeout = port->timeout; 326 327 return timeout > 6 ? (timeout / 2 - 2) : 1; 328 } 329 330 /* 331 * Console helpers. 332 */ 333 struct earlycon_device { 334 struct console *con; 335 struct uart_port port; 336 char options[16]; /* e.g., 115200n8 */ 337 unsigned int baud; 338 }; 339 int setup_earlycon(char *buf, const char *match, 340 int (*setup)(struct earlycon_device *, const char *)); 341 342 extern int of_setup_earlycon(unsigned long addr, 343 int (*setup)(struct earlycon_device *, const char *)); 344 345 #define EARLYCON_DECLARE(name, func) \ 346 static int __init name ## _setup_earlycon(char *buf) \ 347 { \ 348 return setup_earlycon(buf, __stringify(name), func); \ 349 } \ 350 early_param("earlycon", name ## _setup_earlycon); 351 352 #define OF_EARLYCON_DECLARE(name, compat, fn) \ 353 _OF_DECLARE(earlycon, name, compat, fn, void *) 354 355 struct uart_port *uart_get_console(struct uart_port *ports, int nr, 356 struct console *c); 357 void uart_parse_options(char *options, int *baud, int *parity, int *bits, 358 int *flow); 359 int uart_set_options(struct uart_port *port, struct console *co, int baud, 360 int parity, int bits, int flow); 361 struct tty_driver *uart_console_device(struct console *co, int *index); 362 void uart_console_write(struct uart_port *port, const char *s, 363 unsigned int count, 364 void (*putchar)(struct uart_port *, int)); 365 366 /* 367 * Port/driver registration/removal 368 */ 369 int uart_register_driver(struct uart_driver *uart); 370 void uart_unregister_driver(struct uart_driver *uart); 371 int uart_add_one_port(struct uart_driver *reg, struct uart_port *port); 372 int uart_remove_one_port(struct uart_driver *reg, struct uart_port *port); 373 int uart_match_port(struct uart_port *port1, struct uart_port *port2); 374 375 /* 376 * Power Management 377 */ 378 int uart_suspend_port(struct uart_driver *reg, struct uart_port *port); 379 int uart_resume_port(struct uart_driver *reg, struct uart_port *port); 380 381 #define uart_circ_empty(circ) ((circ)->head == (circ)->tail) 382 #define uart_circ_clear(circ) ((circ)->head = (circ)->tail = 0) 383 384 #define uart_circ_chars_pending(circ) \ 385 (CIRC_CNT((circ)->head, (circ)->tail, UART_XMIT_SIZE)) 386 387 #define uart_circ_chars_free(circ) \ 388 (CIRC_SPACE((circ)->head, (circ)->tail, UART_XMIT_SIZE)) 389 390 static inline int uart_tx_stopped(struct uart_port *port) 391 { 392 struct tty_struct *tty = port->state->port.tty; 393 if (tty->stopped || port->hw_stopped) 394 return 1; 395 return 0; 396 } 397 398 static inline bool uart_cts_enabled(struct uart_port *uport) 399 { 400 return !!(uport->status & UPSTAT_CTS_ENABLE); 401 } 402 403 static inline bool uart_softcts_mode(struct uart_port *uport) 404 { 405 upstat_t mask = UPSTAT_CTS_ENABLE | UPSTAT_AUTOCTS; 406 407 return ((uport->status & mask) == UPSTAT_CTS_ENABLE); 408 } 409 410 /* 411 * The following are helper functions for the low level drivers. 412 */ 413 414 extern void uart_handle_dcd_change(struct uart_port *uport, 415 unsigned int status); 416 extern void uart_handle_cts_change(struct uart_port *uport, 417 unsigned int status); 418 419 extern void uart_insert_char(struct uart_port *port, unsigned int status, 420 unsigned int overrun, unsigned int ch, unsigned int flag); 421 422 #ifdef SUPPORT_SYSRQ 423 static inline int 424 uart_handle_sysrq_char(struct uart_port *port, unsigned int ch) 425 { 426 if (port->sysrq) { 427 if (ch && time_before(jiffies, port->sysrq)) { 428 handle_sysrq(ch); 429 port->sysrq = 0; 430 return 1; 431 } 432 port->sysrq = 0; 433 } 434 return 0; 435 } 436 #else 437 #define uart_handle_sysrq_char(port,ch) ({ (void)port; 0; }) 438 #endif 439 440 /* 441 * We do the SysRQ and SAK checking like this... 442 */ 443 static inline int uart_handle_break(struct uart_port *port) 444 { 445 struct uart_state *state = port->state; 446 447 if (port->handle_break) 448 port->handle_break(port); 449 450 #ifdef SUPPORT_SYSRQ 451 if (port->cons && port->cons->index == port->line) { 452 if (!port->sysrq) { 453 port->sysrq = jiffies + HZ*5; 454 return 1; 455 } 456 port->sysrq = 0; 457 } 458 #endif 459 if (port->flags & UPF_SAK) 460 do_SAK(state->port.tty); 461 return 0; 462 } 463 464 /* 465 * UART_ENABLE_MS - determine if port should enable modem status irqs 466 */ 467 #define UART_ENABLE_MS(port,cflag) ((port)->flags & UPF_HARDPPS_CD || \ 468 (cflag) & CRTSCTS || \ 469 !((cflag) & CLOCAL)) 470 471 #endif /* LINUX_SERIAL_CORE_H */ 472