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