include/linux/serial_core.h

   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
  21 /*
  22  * The type definitions.  These are from Ted Ts'o's serial.h
  23  */
  24 #define PORT_UNKNOWN    0
  25 #define PORT_8250       1
  26 #define PORT_16450      2
  27 #define PORT_16550      3
  28 #define PORT_16550A     4
  29 #define PORT_CIRRUS     5
  30 #define PORT_16650      6
  31 #define PORT_16650V2    7
  32 #define PORT_16750      8
  33 #define PORT_STARTECH   9
  34 #define PORT_16C950     10
  35 #define PORT_16654      11
  36 #define PORT_16850      12
  37 #define PORT_RSA        13
  38 #define PORT_NS16550A   14
  39 #define PORT_XSCALE     15
  40 #define PORT_MAX_8250   15      /* max port ID */
  41
  42 /*
  43  * ARM specific type numbers.  These are not currently guaranteed
  44  * to be implemented, and will change in the future.  These are
  45  * separate so any additions to the old serial.c that occur before
  46  * we are merged can be easily merged here.
  47  */
  48 #define PORT_PXA        31
  49 #define PORT_AMBA       32
  50 #define PORT_CLPS711X   33
  51 #define PORT_SA1100     34
  52 #define PORT_UART00     35
  53 #define PORT_P2001      36
  54 #define PORT_21285      37
  55
  56 /* Sparc type numbers.  */
  57 #define PORT_SUNZILOG   38
  58 #define PORT_SUNSAB     39
  59
  60 /* NEC v850.  */
  61 #define PORT_V850E_UART 40
  62
  63 /* DZ */
  64 #define PORT_DZ         47
  65
  66 /* Parisc type numbers. */
  67 #define PORT_MUX        48
  68
  69 /* Motorola ColdFire */
  70 #define PORT_MCF        49
  71
  72 /* Macintosh Zilog type numbers */
  73 #define PORT_MAC_ZILOG  50      /* m68k : not yet implemented */
  74 #define PORT_PMAC_ZILOG 51
  75
  76 /* SH-SCI */
  77 #define PORT_SCI        52
  78 #define PORT_SCIF       53
  79 #define PORT_IRDA       54
  80
  81 /* Samsung S3C2410 SoC and derivatives thereof */
  82 #define PORT_S3C2410    55
  83
  84 /* SGI IP22 aka Indy / Challenge S / Indigo 2 */
  85 #define PORT_IP22ZILOG  56
  86
  87 /* Sharp LH7a40x -- an ARM9 SoC series */
  88 #define PORT_LH7A40X    57
  89
  90 /* PPC CPM type number */
  91 #define PORT_CPM        58
  92
  93 /* MPC52xx type numbers */
  94 #define PORT_MPC52xx    59
  95
  96 /* JTAG emulation port types */
  97 #define PORT_T32_JTAG1  60
  98
  99 /* Samsung S3C4510B */
 100 #define PORT_S3C4510B   61
 101
 102 #ifdef __KERNEL__
 103
 104 #include <linux/config.h>
 105 #include <linux/interrupt.h>
 106 #include <linux/circ_buf.h>
 107 #include <linux/spinlock.h>
 108 #include <linux/sched.h>
 109
 110 struct uart_port;
 111 struct uart_info;
 112 struct serial_struct;
 113 struct device;
 114
 115 /*
 116  * This structure describes all the operations that can be
 117  * done on the physical hardware.
 118  */
 119 struct uart_ops {
 120         unsigned int    (*tx_empty)(struct uart_port *);
 121         void            (*set_mctrl)(struct uart_port *, unsigned int mctrl);
 122         unsigned int    (*get_mctrl)(struct uart_port *);
 123         void            (*stop_tx)(struct uart_port *, unsigned int tty_stop);
 124         void            (*start_tx)(struct uart_port *, unsigned int tty_start);
 125         void            (*send_xchar)(struct uart_port *, char ch);
 126         void            (*stop_rx)(struct uart_port *);
 127         void            (*enable_ms)(struct uart_port *);
 128         void            (*break_ctl)(struct uart_port *, int ctl);
 129         int             (*startup)(struct uart_port *);
 130         void            (*shutdown)(struct uart_port *);
 131         void            (*set_termios)(struct uart_port *, struct termios *new,
 132                                        struct termios *old);
 133         void            (*pm)(struct uart_port *, unsigned int state,
 134                               unsigned int oldstate);
 135         int             (*set_wake)(struct uart_port *, unsigned int state);
 136
 137         /*
 138          * Return a string describing the type of the port
 139          */
 140         const char *(*type)(struct uart_port *);
 141
 142         /*
 143          * Release IO and memory resources used by the port.
 144          * This includes iounmap if necessary.
 145          */
 146         void            (*release_port)(struct uart_port *);
 147
 148         /*
 149          * Request IO and memory resources used by the port.
 150          * This includes iomapping the port if necessary.
 151          */
 152         int             (*request_port)(struct uart_port *);
 153         void            (*config_port)(struct uart_port *, int);
 154         int             (*verify_port)(struct uart_port *, struct serial_struct *);
 155         int             (*ioctl)(struct uart_port *, unsigned int, unsigned long);
 156 };
 157
 158 #define UART_CONFIG_TYPE        (1 << 0)
 159 #define UART_CONFIG_IRQ         (1 << 1)
 160
 161 struct uart_icount {
 162         __u32   cts;
 163         __u32   dsr;
 164         __u32   rng;
 165         __u32   dcd;
 166         __u32   rx;
 167         __u32   tx;
 168         __u32   frame;
 169         __u32   overrun;
 170         __u32   parity;
 171         __u32   brk;
 172         __u32   buf_overrun;
 173 };
 174
 175 struct uart_port {
 176         spinlock_t              lock;                   /* port lock */
 177         unsigned int            iobase;                 /* in/out[bwl] */
 178         char                    *membase;               /* read/write[bwl] */
 179         unsigned int            irq;                    /* irq number */
 180         unsigned int            uartclk;                /* base uart clock */
 181         unsigned char           fifosize;               /* tx fifo size */
 182         unsigned char           x_char;                 /* xon/xoff char */
 183         unsigned char           regshift;               /* reg offset shift */
 184         unsigned char           iotype;                 /* io access style */
 185
 186 #define UPIO_PORT               (0)
 187 #define UPIO_HUB6               (1)
 188 #define UPIO_MEM                (2)
 189 #define UPIO_MEM32              (3)
 190
 191         unsigned int            read_status_mask;       /* driver specific */
 192         unsigned int            ignore_status_mask;     /* driver specific */
 193         struct uart_info        *info;                  /* pointer to parent info */
 194         struct uart_icount      icount;                 /* statistics */
 195
 196         struct console          *cons;                  /* struct console, if any */
 197 #ifdef CONFIG_SERIAL_CORE_CONSOLE
 198         unsigned long           sysrq;                  /* sysrq timeout */
 199 #endif
 200
 201         unsigned int            flags;
 202
 203 #define UPF_FOURPORT            (1 << 1)
 204 #define UPF_SAK                 (1 << 2)
 205 #define UPF_SPD_MASK            (0x1030)
 206 #define UPF_SPD_HI              (0x0010)
 207 #define UPF_SPD_VHI             (0x0020)
 208 #define UPF_SPD_CUST            (0x0030)
 209 #define UPF_SPD_SHI             (0x1000)
 210 #define UPF_SPD_WARP            (0x1010)
 211 #define UPF_SKIP_TEST           (1 << 6)
 212 #define UPF_AUTO_IRQ            (1 << 7)
 213 #define UPF_HARDPPS_CD          (1 << 11)
 214 #define UPF_LOW_LATENCY         (1 << 13)
 215 #define UPF_BUGGY_UART          (1 << 14)
 216 #define UPF_AUTOPROBE           (1 << 15)
 217 #define UPF_MAGIC_MULTIPLIER    (1 << 16)
 218 #define UPF_BOOT_ONLYMCA        (1 << 22)
 219 #define UPF_CONS_FLOW           (1 << 23)
 220 #define UPF_SHARE_IRQ           (1 << 24)
 221 #define UPF_BOOT_AUTOCONF       (1 << 28)
 222 #define UPF_IOREMAP             (1 << 31)
 223
 224 #define UPF_CHANGE_MASK         (0x17fff)
 225 #define UPF_USR_MASK            (UPF_SPD_MASK|UPF_LOW_LATENCY)
 226
 227         unsigned int            mctrl;                  /* current modem ctrl settings */
 228         unsigned int            timeout;                /* character-based timeout */
 229         unsigned int            type;                   /* port type */
 230         struct uart_ops         *ops;
 231         unsigned int            custom_divisor;
 232         unsigned int            line;                   /* port index */
 233         unsigned long           mapbase;                /* for ioremap */
 234         struct device           *dev;                   /* parent device */
 235         unsigned char           hub6;                   /* this should be in the 8250 driver */
 236         unsigned char           unused[3];
 237 };
 238
 239 /*
 240  * This is the state information which is persistent across opens.
 241  * The low level driver must not to touch any elements contained
 242  * within.
 243  */
 244 struct uart_state {
 245         unsigned int            close_delay;
 246         unsigned int            closing_wait;
 247
 248 #define USF_CLOSING_WAIT_INF    (0)
 249 #define USF_CLOSING_WAIT_NONE   (65535)
 250
 251         int                     count;
 252         int                     pm_state;
 253         struct uart_info        *info;
 254         struct uart_port        *port;
 255
 256         struct semaphore        sem;
 257 };
 258
 259 #define UART_XMIT_SIZE 1024
 260 /*
 261  * This is the state information which is only valid when the port
 262  * is open; it may be freed by the core driver once the device has
 263  * been closed.  Either the low level driver or the core can modify
 264  * stuff here.
 265  */
 266 struct uart_info {
 267         struct tty_struct       *tty;
 268         struct circ_buf         xmit;
 269         unsigned int            flags;
 270
 271 /*
 272  * These are the flags that specific to info->flags, and reflect our
 273  * internal state.  They can not be accessed via port->flags.  Low
 274  * level drivers must not change these, but may query them instead.
 275  */
 276 #define UIF_CHECK_CD            (1 << 25)
 277 #define UIF_CTS_FLOW            (1 << 26)
 278 #define UIF_NORMAL_ACTIVE       (1 << 29)
 279 #define UIF_INITIALIZED         (1 << 31)
 280
 281         unsigned char           *tmpbuf;
 282         struct semaphore        tmpbuf_sem;
 283
 284         int                     blocked_open;
 285
 286         struct tasklet_struct   tlet;
 287
 288         wait_queue_head_t       open_wait;
 289         wait_queue_head_t       delta_msr_wait;
 290 };
 291
 292 /* number of characters left in xmit buffer before we ask for more */
 293 #define WAKEUP_CHARS            256
 294
 295 struct module;
 296 struct tty_driver;
 297
 298 struct uart_driver {
 299         struct module           *owner;
 300         const char              *driver_name;
 301         const char              *dev_name;
 302         const char              *devfs_name;
 303         int                      major;
 304         int                      minor;
 305         int                      nr;
 306         struct console          *cons;
 307
 308         /*
 309          * these are private; the low level driver should not
 310          * touch these; they should be initialised to NULL
 311          */
 312         struct uart_state       *state;
 313         struct tty_driver       *tty_driver;
 314 };
 315
 316 void uart_write_wakeup(struct uart_port *port);
 317
 318 /*
 319  * Baud rate helpers.
 320  */
 321 void uart_update_timeout(struct uart_port *port, unsigned int cflag,
 322                          unsigned int baud);
 323 unsigned int uart_get_baud_rate(struct uart_port *port, struct termios *termios,
 324                                 struct termios *old, unsigned int min,
 325                                 unsigned int max);
 326 unsigned int uart_get_divisor(struct uart_port *port, unsigned int baud);
 327
 328 /*
 329  * Console helpers.
 330  */
 331 struct uart_port *uart_get_console(struct uart_port *ports, int nr,
 332                                    struct console *c);
 333 void uart_parse_options(char *options, int *baud, int *parity, int *bits,
 334                         int *flow);
 335 int uart_set_options(struct uart_port *port, struct console *co, int baud,
 336                      int parity, int bits, int flow);
 337 struct tty_driver *uart_console_device(struct console *co, int *index);
 338
 339 /*
 340  * Port/driver registration/removal
 341  */
 342 int uart_register_driver(struct uart_driver *uart);
 343 void uart_unregister_driver(struct uart_driver *uart);
 344 void uart_unregister_port(struct uart_driver *reg, int line);
 345 int uart_register_port(struct uart_driver *reg, struct uart_port *port);
 346 int uart_add_one_port(struct uart_driver *reg, struct uart_port *port);
 347 int uart_remove_one_port(struct uart_driver *reg, struct uart_port *port);
 348
 349 /*
 350  * Power Management
 351  */
 352 int uart_suspend_port(struct uart_driver *reg, struct uart_port *port);
 353 int uart_resume_port(struct uart_driver *reg, struct uart_port *port);
 354
 355 #define uart_circ_empty(circ)           ((circ)->head == (circ)->tail)
 356 #define uart_circ_clear(circ)           ((circ)->head = (circ)->tail = 0)
 357
 358 #define uart_circ_chars_pending(circ)   \
 359         (CIRC_CNT((circ)->head, (circ)->tail, UART_XMIT_SIZE))
 360
 361 #define uart_circ_chars_free(circ)      \
 362         (CIRC_SPACE((circ)->head, (circ)->tail, UART_XMIT_SIZE))
 363
 364 #define uart_tx_stopped(port)           \
 365         ((port)->info->tty->stopped || (port)->info->tty->hw_stopped)
 366
 367 /*
 368  * The following are helper functions for the low level drivers.
 369  */
 370 #ifdef SUPPORT_SYSRQ
 371 static inline int
 372 uart_handle_sysrq_char(struct uart_port *port, unsigned int ch,
 373                        struct pt_regs *regs)
 374 {
 375         if (port->sysrq) {
 376                 if (ch && time_before(jiffies, port->sysrq)) {
 377                         handle_sysrq(ch, regs, NULL);
 378                         port->sysrq = 0;
 379                         return 1;
 380                 }
 381                 port->sysrq = 0;
 382         }
 383         return 0;
 384 }
 385 #else
 386 #define uart_handle_sysrq_char(port,ch,regs)    (0)
 387 #endif
 388
 389 /*
 390  * We do the SysRQ and SAK checking like this...
 391  */
 392 static inline int uart_handle_break(struct uart_port *port)
 393 {
 394         struct uart_info *info = port->info;
 395 #ifdef SUPPORT_SYSRQ
 396         if (port->cons && port->cons->index == port->line) {
 397                 if (!port->sysrq) {
 398                         port->sysrq = jiffies + HZ*5;
 399                         return 1;
 400                 }
 401                 port->sysrq = 0;
 402         }
 403 #endif
 404         if (info->flags & UPF_SAK)
 405                 do_SAK(info->tty);
 406         return 0;
 407 }
 408
 409 /**
 410  *      uart_handle_dcd_change - handle a change of carrier detect state
 411  *      @port: uart_port structure for the open port
 412  *      @status: new carrier detect status, nonzero if active
 413  */
 414 static inline void
 415 uart_handle_dcd_change(struct uart_port *port, unsigned int status)
 416 {
 417         struct uart_info *info = port->info;
 418
 419         port->icount.dcd++;
 420
 421 #ifdef CONFIG_HARD_PPS
 422         if ((port->flags & UPF_HARDPPS_CD) && status)
 423                 hardpps();
 424 #endif
 425
 426         if (info->flags & UIF_CHECK_CD) {
 427                 if (status)
 428                         wake_up_interruptible(&info->open_wait);
 429                 else if (info->tty)
 430                         tty_hangup(info->tty);
 431         }
 432 }
 433
 434 /**
 435  *      uart_handle_cts_change - handle a change of clear-to-send state
 436  *      @port: uart_port structure for the open port
 437  *      @status: new clear to send status, nonzero if active
 438  */
 439 static inline void
 440 uart_handle_cts_change(struct uart_port *port, unsigned int status)
 441 {
 442         struct uart_info *info = port->info;
 443         struct tty_struct *tty = info->tty;
 444
 445         port->icount.cts++;
 446
 447         if (info->flags & UIF_CTS_FLOW) {
 448                 if (tty->hw_stopped) {
 449                         if (status) {
 450                                 tty->hw_stopped = 0;
 451                                 port->ops->start_tx(port, 0);
 452                                 uart_write_wakeup(port);
 453                         }
 454                 } else {
 455                         if (!status) {
 456                                 tty->hw_stopped = 1;
 457                                 port->ops->stop_tx(port, 0);
 458                         }
 459                 }
 460         }
 461 }
 462
 463 /*
 464  *      UART_ENABLE_MS - determine if port should enable modem status irqs
 465  */
 466 #define UART_ENABLE_MS(port,cflag)      ((port)->flags & UPF_HARDPPS_CD || \
 467                                          (cflag) & CRTSCTS || \
 468                                          !((cflag) & CLOCAL))
 469
 470 #endif