| 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 | struct uart_port; |
| 35 | struct serial_struct; |
| 36 | struct device; |
| 37 | |
| 38 | /* |
| 39 | * This structure describes all the operations that can be done on the |
| 40 | * physical hardware. See Documentation/serial/driver for details. |
| 41 | */ |
| 42 | struct uart_ops { |
| 43 | unsigned int (*tx_empty)(struct uart_port *); |
| 44 | void (*set_mctrl)(struct uart_port *, unsigned int mctrl); |
| 45 | unsigned int (*get_mctrl)(struct uart_port *); |
| 46 | void (*stop_tx)(struct uart_port *); |
| 47 | void (*start_tx)(struct uart_port *); |
| 48 | void (*throttle)(struct uart_port *); |
| 49 | void (*unthrottle)(struct uart_port *); |
| 50 | void (*send_xchar)(struct uart_port *, char ch); |
| 51 | void (*stop_rx)(struct uart_port *); |
| 52 | void (*enable_ms)(struct uart_port *); |
| 53 | void (*break_ctl)(struct uart_port *, int ctl); |
| 54 | int (*startup)(struct uart_port *); |
| 55 | void (*shutdown)(struct uart_port *); |
| 56 | void (*flush_buffer)(struct uart_port *); |
| 57 | void (*set_termios)(struct uart_port *, struct ktermios *new, |
| 58 | struct ktermios *old); |
| 59 | void (*set_ldisc)(struct uart_port *, int new); |
| 60 | void (*pm)(struct uart_port *, unsigned int state, |
| 61 | unsigned int oldstate); |
| 62 | int (*set_wake)(struct uart_port *, unsigned int state); |
| 63 | |
| 64 | /* |
| 65 | * Return a string describing the type of the port |
| 66 | */ |
| 67 | const char *(*type)(struct uart_port *); |
| 68 | |
| 69 | /* |
| 70 | * Release IO and memory resources used by the port. |
| 71 | * This includes iounmap if necessary. |
| 72 | */ |
| 73 | void (*release_port)(struct uart_port *); |
| 74 | |
| 75 | /* |
| 76 | * Request IO and memory resources used by the port. |
| 77 | * This includes iomapping the port if necessary. |
| 78 | */ |
| 79 | int (*request_port)(struct uart_port *); |
| 80 | void (*config_port)(struct uart_port *, int); |
| 81 | int (*verify_port)(struct uart_port *, struct serial_struct *); |
| 82 | int (*ioctl)(struct uart_port *, unsigned int, unsigned long); |
| 83 | #ifdef CONFIG_CONSOLE_POLL |
| 84 | int (*poll_init)(struct uart_port *); |
| 85 | void (*poll_put_char)(struct uart_port *, unsigned char); |
| 86 | int (*poll_get_char)(struct uart_port *); |
| 87 | #endif |
| 88 | }; |
| 89 | |
| 90 | #define NO_POLL_CHAR 0x00ff0000 |
| 91 | #define UART_CONFIG_TYPE (1 << 0) |
| 92 | #define UART_CONFIG_IRQ (1 << 1) |
| 93 | |
| 94 | struct uart_icount { |
| 95 | __u32 cts; |
| 96 | __u32 dsr; |
| 97 | __u32 rng; |
| 98 | __u32 dcd; |
| 99 | __u32 rx; |
| 100 | __u32 tx; |
| 101 | __u32 frame; |
| 102 | __u32 overrun; |
| 103 | __u32 parity; |
| 104 | __u32 brk; |
| 105 | __u32 buf_overrun; |
| 106 | }; |
| 107 | |
| 108 | typedef unsigned int __bitwise__ upf_t; |
| 109 | |
| 110 | struct uart_port { |
| 111 | spinlock_t lock; /* port lock */ |
| 112 | unsigned long iobase; /* in/out[bwl] */ |
| 113 | unsigned char __iomem *membase; /* read/write[bwl] */ |
| 114 | unsigned int (*serial_in)(struct uart_port *, int); |
| 115 | void (*serial_out)(struct uart_port *, int, int); |
| 116 | void (*set_termios)(struct uart_port *, |
| 117 | struct ktermios *new, |
| 118 | struct ktermios *old); |
| 119 | int (*handle_irq)(struct uart_port *); |
| 120 | void (*pm)(struct uart_port *, unsigned int state, |
| 121 | unsigned int old); |
| 122 | void (*handle_break)(struct uart_port *); |
| 123 | unsigned int irq; /* irq number */ |
| 124 | unsigned long irqflags; /* irq flags */ |
| 125 | unsigned int uartclk; /* base uart clock */ |
| 126 | unsigned int fifosize; /* tx fifo size */ |
| 127 | unsigned char x_char; /* xon/xoff char */ |
| 128 | unsigned char regshift; /* reg offset shift */ |
| 129 | unsigned char iotype; /* io access style */ |
| 130 | unsigned char unused1; |
| 131 | |
| 132 | #define UPIO_PORT (0) |
| 133 | #define UPIO_HUB6 (1) |
| 134 | #define UPIO_MEM (2) |
| 135 | #define UPIO_MEM32 (3) |
| 136 | #define UPIO_AU (4) /* Au1x00 and RT288x type IO */ |
| 137 | #define UPIO_TSI (5) /* Tsi108/109 type IO */ |
| 138 | |
| 139 | unsigned int read_status_mask; /* driver specific */ |
| 140 | unsigned int ignore_status_mask; /* driver specific */ |
| 141 | struct uart_state *state; /* pointer to parent state */ |
| 142 | struct uart_icount icount; /* statistics */ |
| 143 | |
| 144 | struct console *cons; /* struct console, if any */ |
| 145 | #if defined(CONFIG_SERIAL_CORE_CONSOLE) || defined(SUPPORT_SYSRQ) |
| 146 | unsigned long sysrq; /* sysrq timeout */ |
| 147 | #endif |
| 148 | |
| 149 | upf_t flags; |
| 150 | |
| 151 | #define UPF_FOURPORT ((__force upf_t) (1 << 1)) |
| 152 | #define UPF_SAK ((__force upf_t) (1 << 2)) |
| 153 | #define UPF_SPD_MASK ((__force upf_t) (0x1030)) |
| 154 | #define UPF_SPD_HI ((__force upf_t) (0x0010)) |
| 155 | #define UPF_SPD_VHI ((__force upf_t) (0x0020)) |
| 156 | #define UPF_SPD_CUST ((__force upf_t) (0x0030)) |
| 157 | #define UPF_SPD_SHI ((__force upf_t) (0x1000)) |
| 158 | #define UPF_SPD_WARP ((__force upf_t) (0x1010)) |
| 159 | #define UPF_SKIP_TEST ((__force upf_t) (1 << 6)) |
| 160 | #define UPF_AUTO_IRQ ((__force upf_t) (1 << 7)) |
| 161 | #define UPF_HARDPPS_CD ((__force upf_t) (1 << 11)) |
| 162 | #define UPF_LOW_LATENCY ((__force upf_t) (1 << 13)) |
| 163 | #define UPF_BUGGY_UART ((__force upf_t) (1 << 14)) |
| 164 | #define UPF_NO_TXEN_TEST ((__force upf_t) (1 << 15)) |
| 165 | #define UPF_MAGIC_MULTIPLIER ((__force upf_t) (1 << 16)) |
| 166 | /* Port has hardware-assisted h/w flow control (iow, auto-RTS *not* auto-CTS) */ |
| 167 | #define UPF_HARD_FLOW ((__force upf_t) (1 << 21)) |
| 168 | /* Port has hardware-assisted s/w flow control */ |
| 169 | #define UPF_SOFT_FLOW ((__force upf_t) (1 << 22)) |
| 170 | #define UPF_CONS_FLOW ((__force upf_t) (1 << 23)) |
| 171 | #define UPF_SHARE_IRQ ((__force upf_t) (1 << 24)) |
| 172 | #define UPF_EXAR_EFR ((__force upf_t) (1 << 25)) |
| 173 | #define UPF_BUG_THRE ((__force upf_t) (1 << 26)) |
| 174 | /* The exact UART type is known and should not be probed. */ |
| 175 | #define UPF_FIXED_TYPE ((__force upf_t) (1 << 27)) |
| 176 | #define UPF_BOOT_AUTOCONF ((__force upf_t) (1 << 28)) |
| 177 | #define UPF_FIXED_PORT ((__force upf_t) (1 << 29)) |
| 178 | #define UPF_DEAD ((__force upf_t) (1 << 30)) |
| 179 | #define UPF_IOREMAP ((__force upf_t) (1 << 31)) |
| 180 | |
| 181 | #define UPF_CHANGE_MASK ((__force upf_t) (0x17fff)) |
| 182 | #define UPF_USR_MASK ((__force upf_t) (UPF_SPD_MASK|UPF_LOW_LATENCY)) |
| 183 | |
| 184 | unsigned int mctrl; /* current modem ctrl settings */ |
| 185 | unsigned int timeout; /* character-based timeout */ |
| 186 | unsigned int type; /* port type */ |
| 187 | const struct uart_ops *ops; |
| 188 | unsigned int custom_divisor; |
| 189 | unsigned int line; /* port index */ |
| 190 | resource_size_t mapbase; /* for ioremap */ |
| 191 | struct device *dev; /* parent device */ |
| 192 | unsigned char hub6; /* this should be in the 8250 driver */ |
| 193 | unsigned char suspended; |
| 194 | unsigned char irq_wake; |
| 195 | unsigned char unused[2]; |
| 196 | void *private_data; /* generic platform data pointer */ |
| 197 | }; |
| 198 | |
| 199 | static inline int serial_port_in(struct uart_port *up, int offset) |
| 200 | { |
| 201 | return up->serial_in(up, offset); |
| 202 | } |
| 203 | |
| 204 | static inline void serial_port_out(struct uart_port *up, int offset, int value) |
| 205 | { |
| 206 | up->serial_out(up, offset, value); |
| 207 | } |
| 208 | |
| 209 | /** |
| 210 | * enum uart_pm_state - power states for UARTs |
| 211 | * @UART_PM_STATE_ON: UART is powered, up and operational |
| 212 | * @UART_PM_STATE_OFF: UART is powered off |
| 213 | * @UART_PM_STATE_UNDEFINED: sentinel |
| 214 | */ |
| 215 | enum uart_pm_state { |
| 216 | UART_PM_STATE_ON = 0, |
| 217 | UART_PM_STATE_OFF = 3, /* number taken from ACPI */ |
| 218 | UART_PM_STATE_UNDEFINED, |
| 219 | }; |
| 220 | |
| 221 | /* |
| 222 | * This is the state information which is persistent across opens. |
| 223 | */ |
| 224 | struct uart_state { |
| 225 | struct tty_port port; |
| 226 | |
| 227 | enum uart_pm_state pm_state; |
| 228 | struct circ_buf xmit; |
| 229 | |
| 230 | struct uart_port *uart_port; |
| 231 | }; |
| 232 | |
| 233 | #define UART_XMIT_SIZE PAGE_SIZE |
| 234 | |
| 235 | |
| 236 | /* number of characters left in xmit buffer before we ask for more */ |
| 237 | #define WAKEUP_CHARS 256 |
| 238 | |
| 239 | struct module; |
| 240 | struct tty_driver; |
| 241 | |
| 242 | struct uart_driver { |
| 243 | struct module *owner; |
| 244 | const char *driver_name; |
| 245 | const char *dev_name; |
| 246 | int major; |
| 247 | int minor; |
| 248 | int nr; |
| 249 | struct console *cons; |
| 250 | |
| 251 | /* |
| 252 | * these are private; the low level driver should not |
| 253 | * touch these; they should be initialised to NULL |
| 254 | */ |
| 255 | struct uart_state *state; |
| 256 | struct tty_driver *tty_driver; |
| 257 | }; |
| 258 | |
| 259 | void uart_write_wakeup(struct uart_port *port); |
| 260 | |
| 261 | /* |
| 262 | * Baud rate helpers. |
| 263 | */ |
| 264 | void uart_update_timeout(struct uart_port *port, unsigned int cflag, |
| 265 | unsigned int baud); |
| 266 | unsigned int uart_get_baud_rate(struct uart_port *port, struct ktermios *termios, |
| 267 | struct ktermios *old, unsigned int min, |
| 268 | unsigned int max); |
| 269 | unsigned int uart_get_divisor(struct uart_port *port, unsigned int baud); |
| 270 | |
| 271 | /* Base timer interval for polling */ |
| 272 | static inline int uart_poll_timeout(struct uart_port *port) |
| 273 | { |
| 274 | int timeout = port->timeout; |
| 275 | |
| 276 | return timeout > 6 ? (timeout / 2 - 2) : 1; |
| 277 | } |
| 278 | |
| 279 | /* |
| 280 | * Console helpers. |
| 281 | */ |
| 282 | struct uart_port *uart_get_console(struct uart_port *ports, int nr, |
| 283 | struct console *c); |
| 284 | void uart_parse_options(char *options, int *baud, int *parity, int *bits, |
| 285 | int *flow); |
| 286 | int uart_set_options(struct uart_port *port, struct console *co, int baud, |
| 287 | int parity, int bits, int flow); |
| 288 | struct tty_driver *uart_console_device(struct console *co, int *index); |
| 289 | void uart_console_write(struct uart_port *port, const char *s, |
| 290 | unsigned int count, |
| 291 | void (*putchar)(struct uart_port *, int)); |
| 292 | |
| 293 | /* |
| 294 | * Port/driver registration/removal |
| 295 | */ |
| 296 | int uart_register_driver(struct uart_driver *uart); |
| 297 | void uart_unregister_driver(struct uart_driver *uart); |
| 298 | int uart_add_one_port(struct uart_driver *reg, struct uart_port *port); |
| 299 | int uart_remove_one_port(struct uart_driver *reg, struct uart_port *port); |
| 300 | int uart_match_port(struct uart_port *port1, struct uart_port *port2); |
| 301 | |
| 302 | /* |
| 303 | * Power Management |
| 304 | */ |
| 305 | int uart_suspend_port(struct uart_driver *reg, struct uart_port *port); |
| 306 | int uart_resume_port(struct uart_driver *reg, struct uart_port *port); |
| 307 | |
| 308 | #define uart_circ_empty(circ) ((circ)->head == (circ)->tail) |
| 309 | #define uart_circ_clear(circ) ((circ)->head = (circ)->tail = 0) |
| 310 | |
| 311 | #define uart_circ_chars_pending(circ) \ |
| 312 | (CIRC_CNT((circ)->head, (circ)->tail, UART_XMIT_SIZE)) |
| 313 | |
| 314 | #define uart_circ_chars_free(circ) \ |
| 315 | (CIRC_SPACE((circ)->head, (circ)->tail, UART_XMIT_SIZE)) |
| 316 | |
| 317 | static inline int uart_tx_stopped(struct uart_port *port) |
| 318 | { |
| 319 | struct tty_struct *tty = port->state->port.tty; |
| 320 | if(tty->stopped || tty->hw_stopped) |
| 321 | return 1; |
| 322 | return 0; |
| 323 | } |
| 324 | |
| 325 | /* |
| 326 | * The following are helper functions for the low level drivers. |
| 327 | */ |
| 328 | |
| 329 | extern void uart_handle_dcd_change(struct uart_port *uport, |
| 330 | unsigned int status); |
| 331 | extern void uart_handle_cts_change(struct uart_port *uport, |
| 332 | unsigned int status); |
| 333 | |
| 334 | extern void uart_insert_char(struct uart_port *port, unsigned int status, |
| 335 | unsigned int overrun, unsigned int ch, unsigned int flag); |
| 336 | |
| 337 | #ifdef SUPPORT_SYSRQ |
| 338 | static inline int |
| 339 | uart_handle_sysrq_char(struct uart_port *port, unsigned int ch) |
| 340 | { |
| 341 | if (port->sysrq) { |
| 342 | if (ch && time_before(jiffies, port->sysrq)) { |
| 343 | handle_sysrq(ch); |
| 344 | port->sysrq = 0; |
| 345 | return 1; |
| 346 | } |
| 347 | port->sysrq = 0; |
| 348 | } |
| 349 | return 0; |
| 350 | } |
| 351 | #else |
| 352 | #define uart_handle_sysrq_char(port,ch) ({ (void)port; 0; }) |
| 353 | #endif |
| 354 | |
| 355 | /* |
| 356 | * We do the SysRQ and SAK checking like this... |
| 357 | */ |
| 358 | static inline int uart_handle_break(struct uart_port *port) |
| 359 | { |
| 360 | struct uart_state *state = port->state; |
| 361 | |
| 362 | if (port->handle_break) |
| 363 | port->handle_break(port); |
| 364 | |
| 365 | #ifdef SUPPORT_SYSRQ |
| 366 | if (port->cons && port->cons->index == port->line) { |
| 367 | if (!port->sysrq) { |
| 368 | port->sysrq = jiffies + HZ*5; |
| 369 | return 1; |
| 370 | } |
| 371 | port->sysrq = 0; |
| 372 | } |
| 373 | #endif |
| 374 | if (port->flags & UPF_SAK) |
| 375 | do_SAK(state->port.tty); |
| 376 | return 0; |
| 377 | } |
| 378 | |
| 379 | /* |
| 380 | * UART_ENABLE_MS - determine if port should enable modem status irqs |
| 381 | */ |
| 382 | #define UART_ENABLE_MS(port,cflag) ((port)->flags & UPF_HARDPPS_CD || \ |
| 383 | (cflag) & CRTSCTS || \ |
| 384 | !((cflag) & CLOCAL)) |
| 385 | |
| 386 | #endif /* LINUX_SERIAL_CORE_H */ |