LXR linux/include/linux/serial

   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
  41struct uart_port;
  42struct serial_struct;
  43struct 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 */
  49struct 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
 100struct 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
 114typedef unsigned int __bitwise__ upf_t;
 115
 116struct uart_port {
 117        spinlock_t              lock;                   /* port lock */
 118        unsigned long           iobase;                 /* in/out[bwl] */
 119        unsigned char __iomem   *membase;               /* read/write[bwl] */
 120        unsigned int            (*serial_in)(struct uart_port *, int);
 121        void                    (*serial_out)(struct uart_port *, int, int);
 122        void                    (*set_termios)(struct uart_port *,
 123                                               struct ktermios *new,
 124                                               struct ktermios *old);
 125        int                     (*handle_irq)(struct uart_port *);
 126        void                    (*pm)(struct uart_port *, unsigned int state,
 127                                      unsigned int old);
 128        void                    (*handle_break)(struct uart_port *);
 129        unsigned int            irq;                    /* irq number */
 130        unsigned long           irqflags;               /* irq flags  */
 131        unsigned int            uartclk;                /* base uart clock */
 132        unsigned int            fifosize;               /* tx fifo size */
 133        unsigned char           x_char;                 /* xon/xoff char */
 134        unsigned char           regshift;               /* reg offset shift */
 135        unsigned char           iotype;                 /* io access style */
 136        unsigned char           unused1;
 137
 138#define UPIO_PORT               (0)
 139#define UPIO_HUB6               (1)
 140#define UPIO_MEM                (2)
 141#define UPIO_MEM32              (3)
 142#define UPIO_AU                 (4)                     /* Au1x00 and RT288x type IO */
 143#define UPIO_TSI                (5)                     /* Tsi108/109 type IO */
 144
 145        unsigned int            read_status_mask;       /* driver specific */
 146        unsigned int            ignore_status_mask;     /* driver specific */
 147        struct uart_state       *state;                 /* pointer to parent state */
 148        struct uart_icount      icount;                 /* statistics */
 149
 150        struct console          *cons;                  /* struct console, if any */
 151#if defined(CONFIG_SERIAL_CORE_CONSOLE) || defined(SUPPORT_SYSRQ)
 152        unsigned long           sysrq;                  /* sysrq timeout */
 153#endif
 154
 155        upf_t                   flags;
 156
 157#define UPF_FOURPORT            ((__force upf_t) (1 << 1))
 158#define UPF_SAK                 ((__force upf_t) (1 << 2))
 159#define UPF_SPD_MASK            ((__force upf_t) (0x1030))
 160#define UPF_SPD_HI              ((__force upf_t) (0x0010))
 161#define UPF_SPD_VHI             ((__force upf_t) (0x0020))
 162#define UPF_SPD_CUST            ((__force upf_t) (0x0030))
 163#define UPF_SPD_SHI             ((__force upf_t) (0x1000))
 164#define UPF_SPD_WARP            ((__force upf_t) (0x1010))
 165#define UPF_SKIP_TEST           ((__force upf_t) (1 << 6))
 166#define UPF_AUTO_IRQ            ((__force upf_t) (1 << 7))
 167#define UPF_HARDPPS_CD          ((__force upf_t) (1 << 11))
 168#define UPF_LOW_LATENCY         ((__force upf_t) (1 << 13))
 169#define UPF_BUGGY_UART          ((__force upf_t) (1 << 14))
 170#define UPF_NO_TXEN_TEST        ((__force upf_t) (1 << 15))
 171#define UPF_MAGIC_MULTIPLIER    ((__force upf_t) (1 << 16))
 172/* Port has hardware-assisted h/w flow control (iow, auto-RTS *not* auto-CTS) */
 173#define UPF_HARD_FLOW           ((__force upf_t) (1 << 21))
 174/* Port has hardware-assisted s/w flow control */
 175#define UPF_SOFT_FLOW           ((__force upf_t) (1 << 22))
 176#define UPF_CONS_FLOW           ((__force upf_t) (1 << 23))
 177#define UPF_SHARE_IRQ           ((__force upf_t) (1 << 24))
 178#define UPF_EXAR_EFR            ((__force upf_t) (1 << 25))
 179#define UPF_BUG_THRE            ((__force upf_t) (1 << 26))
 180/* The exact UART type is known and should not be probed.  */
 181#define UPF_FIXED_TYPE          ((__force upf_t) (1 << 27))
 182#define UPF_BOOT_AUTOCONF       ((__force upf_t) (1 << 28))
 183#define UPF_FIXED_PORT          ((__force upf_t) (1 << 29))
 184#define UPF_DEAD                ((__force upf_t) (1 << 30))
 185#define UPF_IOREMAP             ((__force upf_t) (1 << 31))
 186
 187#define UPF_CHANGE_MASK         ((__force upf_t) (0x17fff))
 188#define UPF_USR_MASK            ((__force upf_t) (UPF_SPD_MASK|UPF_LOW_LATENCY))
 189
 190        unsigned int            mctrl;                  /* current modem ctrl settings */
 191        unsigned int            timeout;                /* character-based timeout */
 192        unsigned int            type;                   /* port type */
 193        const struct uart_ops   *ops;
 194        unsigned int            custom_divisor;
 195        unsigned int            line;                   /* port index */
 196        resource_size_t         mapbase;                /* for ioremap */
 197        struct device           *dev;                   /* parent device */
 198        unsigned char           hub6;                   /* this should be in the 8250 driver */
 199        unsigned char           suspended;
 200        unsigned char           irq_wake;
 201        unsigned char           unused[2];
 202        void                    *private_data;          /* generic platform data pointer */
 203};
 204
 205static inline int serial_port_in(struct uart_port *up, int offset)
 206{
 207        return up->serial_in(up, offset);
 208}
 209
 210static inline void serial_port_out(struct uart_port *up, int offset, int value)
 211{
 212        up->serial_out(up, offset, value);
 213}
 214
 215/**
 216 * enum uart_pm_state - power states for UARTs
 217 * @UART_PM_STATE_ON: UART is powered, up and operational
 218 * @UART_PM_STATE_OFF: UART is powered off
 219 * @UART_PM_STATE_UNDEFINED: sentinel
 220 */
 221enum uart_pm_state {
 222        UART_PM_STATE_ON = 0,
 223        UART_PM_STATE_OFF = 3, /* number taken from ACPI */
 224        UART_PM_STATE_UNDEFINED,
 225};
 226
 227/*
 228 * This is the state information which is persistent across opens.
 229 */
 230struct uart_state {
 231        struct tty_port         port;
 232
 233        enum uart_pm_state      pm_state;
 234        struct circ_buf         xmit;
 235
 236        struct uart_port        *uart_port;
 237};
 238
 239#define UART_XMIT_SIZE  PAGE_SIZE
 240
 241
 242/* number of characters left in xmit buffer before we ask for more */
 243#define WAKEUP_CHARS            256
 244
 245struct module;
 246struct tty_driver;
 247
 248struct uart_driver {
 249        struct module           *owner;
 250        const char              *driver_name;
 251        const char              *dev_name;
 252        int                      major;
 253        int                      minor;
 254        int                      nr;
 255        struct console          *cons;
 256
 257        /*
 258         * these are private; the low level driver should not
 259         * touch these; they should be initialised to NULL
 260         */
 261        struct uart_state       *state;
 262        struct tty_driver       *tty_driver;
 263};
 264
 265void uart_write_wakeup(struct uart_port *port);
 266
 267/*
 268 * Baud rate helpers.
 269 */
 270void uart_update_timeout(struct uart_port *port, unsigned int cflag,
 271                         unsigned int baud);
 272unsigned int uart_get_baud_rate(struct uart_port *port, struct ktermios *termios,
 273                                struct ktermios *old, unsigned int min,
 274                                unsigned int max);
 275unsigned int uart_get_divisor(struct uart_port *port, unsigned int baud);
 276
 277/* Base timer interval for polling */
 278static inline int uart_poll_timeout(struct uart_port *port)
 279{
 280        int timeout = port->timeout;
 281
 282        return timeout > 6 ? (timeout / 2 - 2) : 1;
 283}
 284
 285/*
 286 * Console helpers.
 287 */
 288struct uart_port *uart_get_console(struct uart_port *ports, int nr,
 289                                   struct console *c);
 290void uart_parse_options(char *options, int *baud, int *parity, int *bits,
 291                        int *flow);
 292int uart_set_options(struct uart_port *port, struct console *co, int baud,
 293                     int parity, int bits, int flow);
 294struct tty_driver *uart_console_device(struct console *co, int *index);
 295void uart_console_write(struct uart_port *port, const char *s,
 296                        unsigned int count,
 297                        void (*putchar)(struct uart_port *, int));
 298
 299/*
 300 * Port/driver registration/removal
 301 */
 302int uart_register_driver(struct uart_driver *uart);
 303void uart_unregister_driver(struct uart_driver *uart);
 304int uart_add_one_port(struct uart_driver *reg, struct uart_port *port);
 305int uart_remove_one_port(struct uart_driver *reg, struct uart_port *port);
 306int uart_match_port(struct uart_port *port1, struct uart_port *port2);
 307
 308/*
 309 * Power Management
 310 */
 311int uart_suspend_port(struct uart_driver *reg, struct uart_port *port);
 312int uart_resume_port(struct uart_driver *reg, struct uart_port *port);
 313
 314#define uart_circ_empty(circ)           ((circ)->head == (circ)->tail)
 315#define uart_circ_clear(circ)           ((circ)->head = (circ)->tail = 0)
 316
 317#define uart_circ_chars_pending(circ)   \
 318        (CIRC_CNT((circ)->head, (circ)->tail, UART_XMIT_SIZE))
 319
 320#define uart_circ_chars_free(circ)      \
 321        (CIRC_SPACE((circ)->head, (circ)->tail, UART_XMIT_SIZE))
 322
 323static inline int uart_tx_stopped(struct uart_port *port)
 324{
 325        struct tty_struct *tty = port->state->port.tty;
 326        if(tty->stopped || tty->hw_stopped)
 327                return 1;
 328        return 0;
 329}
 330
 331/*
 332 * The following are helper functions for the low level drivers.
 333 */
 334
 335extern void uart_handle_dcd_change(struct uart_port *uport,
 336                unsigned int status);
 337extern void uart_handle_cts_change(struct uart_port *uport,
 338                unsigned int status);
 339
 340extern void uart_insert_char(struct uart_port *port, unsigned int status,
 341                 unsigned int overrun, unsigned int ch, unsigned int flag);
 342
 343#ifdef SUPPORT_SYSRQ
 344static inline int
 345uart_handle_sysrq_char(struct uart_port *port, unsigned int ch)
 346{
 347        if (port->sysrq) {
 348                if (ch && time_before(jiffies, port->sysrq)) {
 349                        handle_sysrq(ch);
 350                        port->sysrq = 0;
 351                        return 1;
 352                }
 353                port->sysrq = 0;
 354        }
 355        return 0;
 356}
 357#else
 358#define uart_handle_sysrq_char(port,ch) ({ (void)port; 0; })
 359#endif
 360
 361/*
 362 * We do the SysRQ and SAK checking like this...
 363 */
 364static inline int uart_handle_break(struct uart_port *port)
 365{
 366        struct uart_state *state = port->state;
 367
 368        if (port->handle_break)
 369                port->handle_break(port);
 370
 371#ifdef SUPPORT_SYSRQ
 372        if (port->cons && port->cons->index == port->line) {
 373                if (!port->sysrq) {
 374                        port->sysrq = jiffies + HZ*5;
 375                        return 1;
 376                }
 377                port->sysrq = 0;
 378        }
 379#endif
 380        if (port->flags & UPF_SAK)
 381                do_SAK(state->port.tty);
 382        return 0;
 383}
 384
 385/*
 386 *      UART_ENABLE_MS - determine if port should enable modem status irqs
 387 */
 388#define UART_ENABLE_MS(port,cflag)      ((port)->flags & UPF_HARDPPS_CD || \
 389                                         (cflag) & CRTSCTS || \
 390                                         !((cflag) & CLOCAL))
 391
 392#endif /* LINUX_SERIAL_CORE_H */
 393