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 <linux/pps_kernel.h>
  33#include <uapi/linux/serial_core.h>
  34
  35struct uart_port;
  36struct serial_struct;
  37struct device;
  38
  39/*
  40 * This structure describes all the operations that can be
  41 * done on the physical hardware.
  42 */
  43struct uart_ops {
  44        unsigned int    (*tx_empty)(struct uart_port *);
  45        void            (*set_mctrl)(struct uart_port *, unsigned int mctrl);
  46        unsigned int    (*get_mctrl)(struct uart_port *);
  47        void            (*stop_tx)(struct uart_port *);
  48        void            (*start_tx)(struct uart_port *);
  49        void            (*send_xchar)(struct uart_port *, char ch);
  50        void            (*stop_rx)(struct uart_port *);
  51        void            (*enable_ms)(struct uart_port *);
  52        void            (*break_ctl)(struct uart_port *, int ctl);
  53        int             (*startup)(struct uart_port *);
  54        void            (*shutdown)(struct uart_port *);
  55        void            (*flush_buffer)(struct uart_port *);
  56        void            (*set_termios)(struct uart_port *, struct ktermios *new,
  57                                       struct ktermios *old);
  58        void            (*set_ldisc)(struct uart_port *, int new);
  59        void            (*pm)(struct uart_port *, unsigned int state,
  60                              unsigned int oldstate);
  61        int             (*set_wake)(struct uart_port *, unsigned int state);
  62
  63        /*
  64         * Return a string describing the type of the port
  65         */
  66        const char *(*type)(struct uart_port *);
  67
  68        /*
  69         * Release IO and memory resources used by the port.
  70         * This includes iounmap if necessary.
  71         */
  72        void            (*release_port)(struct uart_port *);
  73
  74        /*
  75         * Request IO and memory resources used by the port.
  76         * This includes iomapping the port if necessary.
  77         */
  78        int             (*request_port)(struct uart_port *);
  79        void            (*config_port)(struct uart_port *, int);
  80        int             (*verify_port)(struct uart_port *, struct serial_struct *);
  81        int             (*ioctl)(struct uart_port *, unsigned int, unsigned long);
  82#ifdef CONFIG_CONSOLE_POLL
  83        int             (*poll_init)(struct uart_port *);
  84        void    (*poll_put_char)(struct uart_port *, unsigned char);
  85        int             (*poll_get_char)(struct uart_port *);
  86#endif
  87};
  88
  89#define NO_POLL_CHAR            0x00ff0000
  90#define UART_CONFIG_TYPE        (1 << 0)
  91#define UART_CONFIG_IRQ         (1 << 1)
  92
  93struct uart_icount {
  94        __u32   cts;
  95        __u32   dsr;
  96        __u32   rng;
  97        __u32   dcd;
  98        __u32   rx;
  99        __u32   tx;
 100        __u32   frame;
 101        __u32   overrun;
 102        __u32   parity;
 103        __u32   brk;
 104        __u32   buf_overrun;
 105};
 106
 107typedef unsigned int __bitwise__ upf_t;
 108
 109struct uart_port {
 110        spinlock_t              lock;                   /* port lock */
 111        unsigned long           iobase;                 /* in/out[bwl] */
 112        unsigned char __iomem   *membase;               /* read/write[bwl] */
 113        unsigned int            (*serial_in)(struct uart_port *, int);
 114        void                    (*serial_out)(struct uart_port *, int, int);
 115        void                    (*set_termios)(struct uart_port *,
 116                                               struct ktermios *new,
 117                                               struct ktermios *old);
 118        int                     (*handle_irq)(struct uart_port *);
 119        void                    (*pm)(struct uart_port *, unsigned int state,
 120                                      unsigned int old);
 121        void                    (*handle_break)(struct uart_port *);
 122        unsigned int            irq;                    /* irq number */
 123        unsigned long           irqflags;               /* irq flags  */
 124        unsigned int            uartclk;                /* base uart clock */
 125        unsigned int            fifosize;               /* tx fifo size */
 126        unsigned char           x_char;                 /* xon/xoff char */
 127        unsigned char           regshift;               /* reg offset shift */
 128        unsigned char           iotype;                 /* io access style */
 129        unsigned char           unused1;
 130
 131#define UPIO_PORT               (0)
 132#define UPIO_HUB6               (1)
 133#define UPIO_MEM                (2)
 134#define UPIO_MEM32              (3)
 135#define UPIO_AU                 (4)                     /* Au1x00 type IO */
 136#define UPIO_TSI                (5)                     /* Tsi108/109 type IO */
 137#define UPIO_RM9000             (6)                     /* RM9000 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#define UPF_CONS_FLOW           ((__force upf_t) (1 << 23))
 167#define UPF_SHARE_IRQ           ((__force upf_t) (1 << 24))
 168#define UPF_EXAR_EFR            ((__force upf_t) (1 << 25))
 169#define UPF_BUG_THRE            ((__force upf_t) (1 << 26))
 170/* The exact UART type is known and should not be probed.  */
 171#define UPF_FIXED_TYPE          ((__force upf_t) (1 << 27))
 172#define UPF_BOOT_AUTOCONF       ((__force upf_t) (1 << 28))
 173#define UPF_FIXED_PORT          ((__force upf_t) (1 << 29))
 174#define UPF_DEAD                ((__force upf_t) (1 << 30))
 175#define UPF_IOREMAP             ((__force upf_t) (1 << 31))
 176
 177#define UPF_CHANGE_MASK         ((__force upf_t) (0x17fff))
 178#define UPF_USR_MASK            ((__force upf_t) (UPF_SPD_MASK|UPF_LOW_LATENCY))
 179
 180        unsigned int            mctrl;                  /* current modem ctrl settings */
 181        unsigned int            timeout;                /* character-based timeout */
 182        unsigned int            type;                   /* port type */
 183        const struct uart_ops   *ops;
 184        unsigned int            custom_divisor;
 185        unsigned int            line;                   /* port index */
 186        resource_size_t         mapbase;                /* for ioremap */
 187        struct device           *dev;                   /* parent device */
 188        unsigned char           hub6;                   /* this should be in the 8250 driver */
 189        unsigned char           suspended;
 190        unsigned char           irq_wake;
 191        unsigned char           unused[2];
 192        void                    *private_data;          /* generic platform data pointer */
 193};
 194
 195static inline int serial_port_in(struct uart_port *up, int offset)
 196{
 197        return up->serial_in(up, offset);
 198}
 199
 200static inline void serial_port_out(struct uart_port *up, int offset, int value)
 201{
 202        up->serial_out(up, offset, value);
 203}
 204
 205/*
 206 * This is the state information which is persistent across opens.
 207 */
 208struct uart_state {
 209        struct tty_port         port;
 210
 211        int                     pm_state;
 212        struct circ_buf         xmit;
 213
 214        struct uart_port        *uart_port;
 215};
 216
 217#define UART_XMIT_SIZE  PAGE_SIZE
 218
 219
 220/* number of characters left in xmit buffer before we ask for more */
 221#define WAKEUP_CHARS            256
 222
 223struct module;
 224struct tty_driver;
 225
 226struct uart_driver {
 227        struct module           *owner;
 228        const char              *driver_name;
 229        const char              *dev_name;
 230        int                      major;
 231        int                      minor;
 232        int                      nr;
 233        struct console          *cons;
 234
 235        /*
 236         * these are private; the low level driver should not
 237         * touch these; they should be initialised to NULL
 238         */
 239        struct uart_state       *state;
 240        struct tty_driver       *tty_driver;
 241};
 242
 243void uart_write_wakeup(struct uart_port *port);
 244
 245/*
 246 * Baud rate helpers.
 247 */
 248void uart_update_timeout(struct uart_port *port, unsigned int cflag,
 249                         unsigned int baud);
 250unsigned int uart_get_baud_rate(struct uart_port *port, struct ktermios *termios,
 251                                struct ktermios *old, unsigned int min,
 252                                unsigned int max);
 253unsigned int uart_get_divisor(struct uart_port *port, unsigned int baud);
 254
 255/* Base timer interval for polling */
 256static inline int uart_poll_timeout(struct uart_port *port)
 257{
 258        int timeout = port->timeout;
 259
 260        return timeout > 6 ? (timeout / 2 - 2) : 1;
 261}
 262
 263/*
 264 * Console helpers.
 265 */
 266struct uart_port *uart_get_console(struct uart_port *ports, int nr,
 267                                   struct console *c);
 268void uart_parse_options(char *options, int *baud, int *parity, int *bits,
 269                        int *flow);
 270int uart_set_options(struct uart_port *port, struct console *co, int baud,
 271                     int parity, int bits, int flow);
 272struct tty_driver *uart_console_device(struct console *co, int *index);
 273void uart_console_write(struct uart_port *port, const char *s,
 274                        unsigned int count,
 275                        void (*putchar)(struct uart_port *, int));
 276
 277/*
 278 * Port/driver registration/removal
 279 */
 280int uart_register_driver(struct uart_driver *uart);
 281void uart_unregister_driver(struct uart_driver *uart);
 282int uart_add_one_port(struct uart_driver *reg, struct uart_port *port);
 283int uart_remove_one_port(struct uart_driver *reg, struct uart_port *port);
 284int uart_match_port(struct uart_port *port1, struct uart_port *port2);
 285
 286/*
 287 * Power Management
 288 */
 289int uart_suspend_port(struct uart_driver *reg, struct uart_port *port);
 290int uart_resume_port(struct uart_driver *reg, struct uart_port *port);
 291
 292#define uart_circ_empty(circ)           ((circ)->head == (circ)->tail)
 293#define uart_circ_clear(circ)           ((circ)->head = (circ)->tail = 0)
 294
 295#define uart_circ_chars_pending(circ)   \
 296        (CIRC_CNT((circ)->head, (circ)->tail, UART_XMIT_SIZE))
 297
 298#define uart_circ_chars_free(circ)      \
 299        (CIRC_SPACE((circ)->head, (circ)->tail, UART_XMIT_SIZE))
 300
 301static inline int uart_tx_stopped(struct uart_port *port)
 302{
 303        struct tty_struct *tty = port->state->port.tty;
 304        if(tty->stopped || tty->hw_stopped)
 305                return 1;
 306        return 0;
 307}
 308
 309/*
 310 * The following are helper functions for the low level drivers.
 311 */
 312
 313extern void uart_handle_dcd_change(struct uart_port *uport,
 314                unsigned int status);
 315extern void uart_handle_cts_change(struct uart_port *uport,
 316                unsigned int status);
 317
 318extern void uart_insert_char(struct uart_port *port, unsigned int status,
 319                 unsigned int overrun, unsigned int ch, unsigned int flag);
 320
 321#ifdef SUPPORT_SYSRQ
 322static inline int
 323uart_handle_sysrq_char(struct uart_port *port, unsigned int ch)
 324{
 325        if (port->sysrq) {
 326                if (ch && time_before(jiffies, port->sysrq)) {
 327                        handle_sysrq(ch);
 328                        port->sysrq = 0;
 329                        return 1;
 330                }
 331                port->sysrq = 0;
 332        }
 333        return 0;
 334}
 335#else
 336#define uart_handle_sysrq_char(port,ch) ({ (void)port; 0; })
 337#endif
 338
 339/*
 340 * We do the SysRQ and SAK checking like this...
 341 */
 342static inline int uart_handle_break(struct uart_port *port)
 343{
 344        struct uart_state *state = port->state;
 345
 346        if (port->handle_break)
 347                port->handle_break(port);
 348
 349#ifdef SUPPORT_SYSRQ
 350        if (port->cons && port->cons->index == port->line) {
 351                if (!port->sysrq) {
 352                        port->sysrq = jiffies + HZ*5;
 353                        return 1;
 354                }
 355                port->sysrq = 0;
 356        }
 357#endif
 358        if (port->flags & UPF_SAK)
 359                do_SAK(state->port.tty);
 360        return 0;
 361}
 362
 363/*
 364 *      UART_ENABLE_MS - determine if port should enable modem status irqs
 365 */
 366#define UART_ENABLE_MS(port,cflag)      ((port)->flags & UPF_HARDPPS_CD || \
 367                                         (cflag) & CRTSCTS || \
 368                                         !((cflag) & CLOCAL))
 369
 370#endif /* LINUX_SERIAL_CORE_H */
 371