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 *, int new); 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 unsigned int irq; /* irq number */ 135 unsigned long irqflags; /* irq flags */ 136 unsigned int uartclk; /* base uart clock */ 137 unsigned int fifosize; /* tx fifo size */ 138 unsigned char x_char; /* xon/xoff char */ 139 unsigned char regshift; /* reg offset shift */ 140 unsigned char iotype; /* io access style */ 141 unsigned char unused1; 142 143 #define UPIO_PORT (0) 144 #define UPIO_HUB6 (1) 145 #define UPIO_MEM (2) 146 #define UPIO_MEM32 (3) 147 #define UPIO_AU (4) /* Au1x00 and RT288x type IO */ 148 #define UPIO_TSI (5) /* Tsi108/109 type IO */ 149 150 unsigned int read_status_mask; /* driver specific */ 151 unsigned int ignore_status_mask; /* driver specific */ 152 struct uart_state *state; /* pointer to parent state */ 153 struct uart_icount icount; /* statistics */ 154 155 struct console *cons; /* struct console, if any */ 156 #if defined(CONFIG_SERIAL_CORE_CONSOLE) || defined(SUPPORT_SYSRQ) 157 unsigned long sysrq; /* sysrq timeout */ 158 #endif 159 160 /* flags must be updated while holding port mutex */ 161 upf_t flags; 162 163 #define UPF_FOURPORT ((__force upf_t) (1 << 1)) 164 #define UPF_SAK ((__force upf_t) (1 << 2)) 165 #define UPF_SPD_MASK ((__force upf_t) (0x1030)) 166 #define UPF_SPD_HI ((__force upf_t) (0x0010)) 167 #define UPF_SPD_VHI ((__force upf_t) (0x0020)) 168 #define UPF_SPD_CUST ((__force upf_t) (0x0030)) 169 #define UPF_SPD_SHI ((__force upf_t) (0x1000)) 170 #define UPF_SPD_WARP ((__force upf_t) (0x1010)) 171 #define UPF_SKIP_TEST ((__force upf_t) (1 << 6)) 172 #define UPF_AUTO_IRQ ((__force upf_t) (1 << 7)) 173 #define UPF_HARDPPS_CD ((__force upf_t) (1 << 11)) 174 #define UPF_LOW_LATENCY ((__force upf_t) (1 << 13)) 175 #define UPF_BUGGY_UART ((__force upf_t) (1 << 14)) 176 #define UPF_NO_TXEN_TEST ((__force upf_t) (1 << 15)) 177 #define UPF_MAGIC_MULTIPLIER ((__force upf_t) (1 << 16)) 178 /* Port has hardware-assisted h/w flow control (iow, auto-RTS *not* auto-CTS) */ 179 #define UPF_HARD_FLOW ((__force upf_t) (1 << 21)) 180 /* Port has hardware-assisted s/w flow control */ 181 #define UPF_SOFT_FLOW ((__force upf_t) (1 << 22)) 182 #define UPF_CONS_FLOW ((__force upf_t) (1 << 23)) 183 #define UPF_SHARE_IRQ ((__force upf_t) (1 << 24)) 184 #define UPF_EXAR_EFR ((__force upf_t) (1 << 25)) 185 #define UPF_BUG_THRE ((__force upf_t) (1 << 26)) 186 /* The exact UART type is known and should not be probed. */ 187 #define UPF_FIXED_TYPE ((__force upf_t) (1 << 27)) 188 #define UPF_BOOT_AUTOCONF ((__force upf_t) (1 << 28)) 189 #define UPF_FIXED_PORT ((__force upf_t) (1 << 29)) 190 #define UPF_DEAD ((__force upf_t) (1 << 30)) 191 #define UPF_IOREMAP ((__force upf_t) (1 << 31)) 192 193 #define UPF_CHANGE_MASK ((__force upf_t) (0x17fff)) 194 #define UPF_USR_MASK ((__force upf_t) (UPF_SPD_MASK|UPF_LOW_LATENCY)) 195 196 /* status must be updated while holding port lock */ 197 upstat_t status; 198 199 #define UPSTAT_CTS_ENABLE ((__force upstat_t) (1 << 0)) 200 #define UPSTAT_DCD_ENABLE ((__force upstat_t) (1 << 1)) 201 202 int hw_stopped; /* sw-assisted CTS flow state */ 203 unsigned int mctrl; /* current modem ctrl settings */ 204 unsigned int timeout; /* character-based timeout */ 205 unsigned int type; /* port type */ 206 const struct uart_ops *ops; 207 unsigned int custom_divisor; 208 unsigned int line; /* port index */ 209 resource_size_t mapbase; /* for ioremap */ 210 struct device *dev; /* parent device */ 211 unsigned char hub6; /* this should be in the 8250 driver */ 212 unsigned char suspended; 213 unsigned char irq_wake; 214 unsigned char unused[2]; 215 struct attribute_group *attr_group; /* port specific attributes */ 216 const struct attribute_group **tty_groups; /* all attributes (serial core use only) */ 217 void *private_data; /* generic platform data pointer */ 218 }; 219 220 static inline int serial_port_in(struct uart_port *up, int offset) 221 { 222 return up->serial_in(up, offset); 223 } 224 225 static inline void serial_port_out(struct uart_port *up, int offset, int value) 226 { 227 up->serial_out(up, offset, value); 228 } 229 230 /** 231 * enum uart_pm_state - power states for UARTs 232 * @UART_PM_STATE_ON: UART is powered, up and operational 233 * @UART_PM_STATE_OFF: UART is powered off 234 * @UART_PM_STATE_UNDEFINED: sentinel 235 */ 236 enum uart_pm_state { 237 UART_PM_STATE_ON = 0, 238 UART_PM_STATE_OFF = 3, /* number taken from ACPI */ 239 UART_PM_STATE_UNDEFINED, 240 }; 241 242 /* 243 * This is the state information which is persistent across opens. 244 */ 245 struct uart_state { 246 struct tty_port port; 247 248 enum uart_pm_state pm_state; 249 struct circ_buf xmit; 250 251 struct uart_port *uart_port; 252 }; 253 254 #define UART_XMIT_SIZE PAGE_SIZE 255 256 257 /* number of characters left in xmit buffer before we ask for more */ 258 #define WAKEUP_CHARS 256 259 260 struct module; 261 struct tty_driver; 262 263 struct uart_driver { 264 struct module *owner; 265 const char *driver_name; 266 const char *dev_name; 267 int major; 268 int minor; 269 int nr; 270 struct console *cons; 271 272 /* 273 * these are private; the low level driver should not 274 * touch these; they should be initialised to NULL 275 */ 276 struct uart_state *state; 277 struct tty_driver *tty_driver; 278 }; 279 280 void uart_write_wakeup(struct uart_port *port); 281 282 /* 283 * Baud rate helpers. 284 */ 285 void uart_update_timeout(struct uart_port *port, unsigned int cflag, 286 unsigned int baud); 287 unsigned int uart_get_baud_rate(struct uart_port *port, struct ktermios *termios, 288 struct ktermios *old, unsigned int min, 289 unsigned int max); 290 unsigned int uart_get_divisor(struct uart_port *port, unsigned int baud); 291 292 /* Base timer interval for polling */ 293 static inline int uart_poll_timeout(struct uart_port *port) 294 { 295 int timeout = port->timeout; 296 297 return timeout > 6 ? (timeout / 2 - 2) : 1; 298 } 299 300 /* 301 * Console helpers. 302 */ 303 struct earlycon_device { 304 struct console *con; 305 struct uart_port port; 306 char options[16]; /* e.g., 115200n8 */ 307 unsigned int baud; 308 }; 309 int setup_earlycon(char *buf, const char *match, 310 int (*setup)(struct earlycon_device *, const char *)); 311 312 extern int of_setup_earlycon(unsigned long addr, 313 int (*setup)(struct earlycon_device *, const char *)); 314 315 #define EARLYCON_DECLARE(name, func) \ 316 static int __init name ## _setup_earlycon(char *buf) \ 317 { \ 318 return setup_earlycon(buf, __stringify(name), func); \ 319 } \ 320 early_param("earlycon", name ## _setup_earlycon); 321 322 #define OF_EARLYCON_DECLARE(name, compat, fn) \ 323 _OF_DECLARE(earlycon, name, compat, fn, void *) 324 325 struct uart_port *uart_get_console(struct uart_port *ports, int nr, 326 struct console *c); 327 void uart_parse_options(char *options, int *baud, int *parity, int *bits, 328 int *flow); 329 int uart_set_options(struct uart_port *port, struct console *co, int baud, 330 int parity, int bits, int flow); 331 struct tty_driver *uart_console_device(struct console *co, int *index); 332 void uart_console_write(struct uart_port *port, const char *s, 333 unsigned int count, 334 void (*putchar)(struct uart_port *, int)); 335 336 /* 337 * Port/driver registration/removal 338 */ 339 int uart_register_driver(struct uart_driver *uart); 340 void uart_unregister_driver(struct uart_driver *uart); 341 int uart_add_one_port(struct uart_driver *reg, struct uart_port *port); 342 int uart_remove_one_port(struct uart_driver *reg, struct uart_port *port); 343 int uart_match_port(struct uart_port *port1, struct uart_port *port2); 344 345 /* 346 * Power Management 347 */ 348 int uart_suspend_port(struct uart_driver *reg, struct uart_port *port); 349 int uart_resume_port(struct uart_driver *reg, struct uart_port *port); 350 351 #define uart_circ_empty(circ) ((circ)->head == (circ)->tail) 352 #define uart_circ_clear(circ) ((circ)->head = (circ)->tail = 0) 353 354 #define uart_circ_chars_pending(circ) \ 355 (CIRC_CNT((circ)->head, (circ)->tail, UART_XMIT_SIZE)) 356 357 #define uart_circ_chars_free(circ) \ 358 (CIRC_SPACE((circ)->head, (circ)->tail, UART_XMIT_SIZE)) 359 360 static inline int uart_tx_stopped(struct uart_port *port) 361 { 362 struct tty_struct *tty = port->state->port.tty; 363 if (tty->stopped || port->hw_stopped) 364 return 1; 365 return 0; 366 } 367 368 static inline bool uart_cts_enabled(struct uart_port *uport) 369 { 370 return uport->status & UPSTAT_CTS_ENABLE; 371 } 372 373 /* 374 * The following are helper functions for the low level drivers. 375 */ 376 377 extern void uart_handle_dcd_change(struct uart_port *uport, 378 unsigned int status); 379 extern void uart_handle_cts_change(struct uart_port *uport, 380 unsigned int status); 381 382 extern void uart_insert_char(struct uart_port *port, unsigned int status, 383 unsigned int overrun, unsigned int ch, unsigned int flag); 384 385 #ifdef SUPPORT_SYSRQ 386 static inline int 387 uart_handle_sysrq_char(struct uart_port *port, unsigned int ch) 388 { 389 if (port->sysrq) { 390 if (ch && time_before(jiffies, port->sysrq)) { 391 handle_sysrq(ch); 392 port->sysrq = 0; 393 return 1; 394 } 395 port->sysrq = 0; 396 } 397 return 0; 398 } 399 #else 400 #define uart_handle_sysrq_char(port,ch) ({ (void)port; 0; }) 401 #endif 402 403 /* 404 * We do the SysRQ and SAK checking like this... 405 */ 406 static inline int uart_handle_break(struct uart_port *port) 407 { 408 struct uart_state *state = port->state; 409 410 if (port->handle_break) 411 port->handle_break(port); 412 413 #ifdef SUPPORT_SYSRQ 414 if (port->cons && port->cons->index == port->line) { 415 if (!port->sysrq) { 416 port->sysrq = jiffies + HZ*5; 417 return 1; 418 } 419 port->sysrq = 0; 420 } 421 #endif 422 if (port->flags & UPF_SAK) 423 do_SAK(state->port.tty); 424 return 0; 425 } 426 427 /* 428 * UART_ENABLE_MS - determine if port should enable modem status irqs 429 */ 430 #define UART_ENABLE_MS(port,cflag) ((port)->flags & UPF_HARDPPS_CD || \ 431 (cflag) & CRTSCTS || \ 432 !((cflag) & CLOCAL)) 433 434 #endif /* LINUX_SERIAL_CORE_H */ 435