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_21285      37
  54
  55 /* Sparc type numbers.  */
  56 #define PORT_SUNZILOG   38
  57 #define PORT_SUNSAB     39
  58
  59 /* NEC v850.  */
  60 #define PORT_V850E_UART 40
  61
  62 /* DZ */
  63 #define PORT_DZ         47
  64
  65 /* Parisc type numbers. */
  66 #define PORT_MUX        48
  67
  68 /* Macintosh Zilog type numbers */
  69 #define PORT_MAC_ZILOG  50      /* m68k : not yet implemented */
  70 #define PORT_PMAC_ZILOG 51
  71
  72 /* SH-SCI */
  73 #define PORT_SCI        52
  74 #define PORT_SCIF       53
  75 #define PORT_IRDA       54
  76
  77 /* Samsung S3C2410 SoC and derivatives thereof */
  78 #define PORT_S3C2410    55
  79
  80 /* SGI IP22 aka Indy / Challenge S / Indigo 2 */
  81 #define PORT_IP22ZILOG  56
  82
  83 /* Sharp LH7a40x -- an ARM9 SoC series */
  84 #define PORT_LH7A40X    57
  85
  86 /* PPC CPM type number */
  87 #define PORT_CPM        58
  88
  89 /* MPC52xx type numbers */
  90 #define PORT_MPC52xx    59
  91
  92 #ifdef __KERNEL__
  93
  94 #include <linux/config.h>
  95 #include <linux/interrupt.h>
  96 #include <linux/circ_buf.h>
  97 #include <linux/spinlock.h>
  98 #include <linux/sched.h>
  99
 100 struct uart_port;
 101 struct uart_info;
 102 struct serial_struct;
 103 struct device;
 104
 105 /*
 106  * This structure describes all the operations that can be
 107  * done on the physical hardware.
 108  */
 109 struct uart_ops {
 110         unsigned int    (*tx_empty)(struct uart_port *);
 111         void            (*set_mctrl)(struct uart_port *, unsigned int mctrl);
 112         unsigned int    (*get_mctrl)(struct uart_port *);
 113         void            (*stop_tx)(struct uart_port *, unsigned int tty_stop);
 114         void            (*start_tx)(struct uart_port *, unsigned int tty_start);
 115         void            (*send_xchar)(struct uart_port *, char ch);
 116         void            (*stop_rx)(struct uart_port *);
 117         void            (*enable_ms)(struct uart_port *);
 118         void            (*break_ctl)(struct uart_port *, int ctl);
 119         int             (*startup)(struct uart_port *);
 120         void            (*shutdown)(struct uart_port *);
 121         void            (*set_termios)(struct uart_port *, struct termios *new,
 122                                        struct termios *old);
 123         void            (*pm)(struct uart_port *, unsigned int state,
 124                               unsigned int oldstate);
 125         int             (*set_wake)(struct uart_port *, unsigned int state);
 126
 127         /*
 128          * Return a string describing the type of the port
 129          */
 130         const char *(*type)(struct uart_port *);
 131
 132         /*
 133          * Release IO and memory resources used by the port.
 134          * This includes iounmap if necessary.
 135          */
 136         void            (*release_port)(struct uart_port *);
 137
 138         /*
 139          * Request IO and memory resources used by the port.
 140          * This includes iomapping the port if necessary.
 141          */
 142         int             (*request_port)(struct uart_port *);
 143         void            (*config_port)(struct uart_port *, int);
 144         int             (*verify_port)(struct uart_port *, struct serial_struct *);
 145         int             (*ioctl)(struct uart_port *, unsigned int, unsigned long);
 146 };
 147
 148 #define UART_CONFIG_TYPE        (1 << 0)
 149 #define UART_CONFIG_IRQ         (1 << 1)
 150
 151 struct uart_icount {
 152         __u32   cts;
 153         __u32   dsr;
 154         __u32   rng;
 155         __u32   dcd;
 156         __u32   rx;
 157         __u32   tx;
 158         __u32   frame;
 159         __u32   overrun;
 160         __u32   parity;
 161         __u32   brk;
 162         __u32   buf_overrun;
 163 };
 164
 165 struct uart_port {
 166         spinlock_t              lock;                   /* port lock */
 167         unsigned int            iobase;                 /* in/out[bwl] */
 168         char                    *membase;               /* read/write[bwl] */
 169         unsigned int            irq;                    /* irq number */
 170         unsigned int            uartclk;                /* base uart clock */
 171         unsigned char           fifosize;               /* tx fifo size */
 172         unsigned char           x_char;                 /* xon/xoff char */
 173         unsigned char           regshift;               /* reg offset shift */
 174         unsigned char           iotype;                 /* io access style */
 175
 176 #define UPIO_PORT               (0)
 177 #define UPIO_HUB6               (1)
 178 #define UPIO_MEM                (2)
 179 #define UPIO_MEM32              (3)
 180
 181         unsigned int            read_status_mask;       /* driver specific */
 182         unsigned int            ignore_status_mask;     /* driver specific */
 183         struct uart_info        *info;                  /* pointer to parent info */
 184         struct uart_icount      icount;                 /* statistics */
 185
 186         struct console          *cons;                  /* struct console, if any */
 187 #ifdef CONFIG_SERIAL_CORE_CONSOLE
 188         unsigned long           sysrq;                  /* sysrq timeout */
 189 #endif
 190
 191         unsigned int            flags;
 192
 193 #define UPF_FOURPORT            (1 << 1)
 194 #define UPF_SAK                 (1 << 2)
 195 #define UPF_SPD_MASK            (0x1030)
 196 #define UPF_SPD_HI              (0x0010)
 197 #define UPF_SPD_VHI             (0x0020)
 198 #define UPF_SPD_CUST            (0x0030)
 199 #define UPF_SPD_SHI             (0x1000)
 200 #define UPF_SPD_WARP            (0x1010)
 201 #define UPF_SKIP_TEST           (1 << 6)
 202 #define UPF_AUTO_IRQ            (1 << 7)
 203 #define UPF_HARDPPS_CD          (1 << 11)
 204 #define UPF_LOW_LATENCY         (1 << 13)
 205 #define UPF_BUGGY_UART          (1 << 14)
 206 #define UPF_AUTOPROBE           (1 << 15)
 207 #define UPF_MAGIC_MULTIPLIER    (1 << 16)
 208 #define UPF_BOOT_ONLYMCA        (1 << 22)
 209 #define UPF_CONS_FLOW           (1 << 23)
 210 #define UPF_SHARE_IRQ           (1 << 24)
 211 #define UPF_BOOT_AUTOCONF       (1 << 28)
 212 #define UPF_IOREMAP             (1 << 31)
 213
 214 #define UPF_CHANGE_MASK         (0x17fff)
 215 #define UPF_USR_MASK            (UPF_SPD_MASK|UPF_LOW_LATENCY)
 216
 217         unsigned int            mctrl;                  /* current modem ctrl settings */
 218         unsigned int            timeout;                /* character-based timeout */
 219         unsigned int            type;                   /* port type */
 220         struct uart_ops         *ops;
 221         unsigned int            custom_divisor;
 222         unsigned int            line;                   /* port index */
 223         unsigned long           mapbase;                /* for ioremap */
 224         struct device           *dev;                   /* parent device */
 225         unsigned char           hub6;                   /* this should be in the 8250 driver */
 226         unsigned char           unused[3];
 227 };
 228
 229 /*
 230  * This is the state information which is persistent across opens.
 231  * The low level driver must not to touch any elements contained
 232  * within.
 233  */
 234 struct uart_state {
 235         unsigned int            close_delay;
 236         unsigned int            closing_wait;
 237
 238 #define USF_CLOSING_WAIT_INF    (0)
 239 #define USF_CLOSING_WAIT_NONE   (65535)
 240
 241         int                     count;
 242         int                     pm_state;
 243         struct uart_info        *info;
 244         struct uart_port        *port;
 245
 246         struct semaphore        sem;
 247 };
 248
 249 #define UART_XMIT_SIZE 1024
 250 /*
 251  * This is the state information which is only valid when the port
 252  * is open; it may be freed by the core driver once the device has
 253  * been closed.  Either the low level driver or the core can modify
 254  * stuff here.
 255  */
 256 struct uart_info {
 257         struct tty_struct       *tty;
 258         struct circ_buf         xmit;
 259         unsigned int            flags;
 260
 261 /*
 262  * These are the flags that specific to info->flags, and reflect our
 263  * internal state.  They can not be accessed via port->flags.  Low
 264  * level drivers must not change these, but may query them instead.
 265  */
 266 #define UIF_CHECK_CD            (1 << 25)
 267 #define UIF_CTS_FLOW            (1 << 26)
 268 #define UIF_NORMAL_ACTIVE       (1 << 29)
 269 #define UIF_INITIALIZED         (1 << 31)
 270
 271         unsigned char           *tmpbuf;
 272         struct semaphore        tmpbuf_sem;
 273
 274         int                     blocked_open;
 275
 276         struct tasklet_struct   tlet;
 277
 278         wait_queue_head_t       open_wait;
 279         wait_queue_head_t       delta_msr_wait;
 280 };
 281
 282 /* number of characters left in xmit buffer before we ask for more */
 283 #define WAKEUP_CHARS            256
 284
 285 struct module;
 286 struct tty_driver;
 287
 288 struct uart_driver {
 289         struct module           *owner;
 290         const char              *driver_name;
 291         const char              *dev_name;
 292         const char              *devfs_name;
 293         int                      major;
 294         int                      minor;
 295         int                      nr;
 296         struct console          *cons;
 297
 298         /*
 299          * these are private; the low level driver should not
 300          * touch these; they should be initialised to NULL
 301          */
 302         struct uart_state       *state;
 303         struct tty_driver       *tty_driver;
 304 };
 305
 306 void uart_write_wakeup(struct uart_port *port);
 307
 308 /*
 309  * Baud rate helpers.
 310  */
 311 void uart_update_timeout(struct uart_port *port, unsigned int cflag,
 312                          unsigned int baud);
 313 unsigned int uart_get_baud_rate(struct uart_port *port, struct termios *termios,
 314                                 struct termios *old, unsigned int min,
 315                                 unsigned int max);
 316 unsigned int uart_get_divisor(struct uart_port *port, unsigned int baud);
 317
 318 /*
 319  * Console helpers.
 320  */
 321 struct uart_port *uart_get_console(struct uart_port *ports, int nr,
 322                                    struct console *c);
 323 void uart_parse_options(char *options, int *baud, int *parity, int *bits,
 324                         int *flow);
 325 int uart_set_options(struct uart_port *port, struct console *co, int baud,
 326                      int parity, int bits, int flow);
 327 struct tty_driver *uart_console_device(struct console *co, int *index);
 328
 329 /*
 330  * Port/driver registration/removal
 331  */
 332 int uart_register_driver(struct uart_driver *uart);
 333 void uart_unregister_driver(struct uart_driver *uart);
 334 void uart_unregister_port(struct uart_driver *reg, int line);
 335 int uart_register_port(struct uart_driver *reg, struct uart_port *port);
 336 int uart_add_one_port(struct uart_driver *reg, struct uart_port *port);
 337 int uart_remove_one_port(struct uart_driver *reg, struct uart_port *port);
 338
 339 /*
 340  * Power Management
 341  */
 342 int uart_suspend_port(struct uart_driver *reg, struct uart_port *port);
 343 int uart_resume_port(struct uart_driver *reg, struct uart_port *port);
 344
 345 #define uart_circ_empty(circ)           ((circ)->head == (circ)->tail)
 346 #define uart_circ_clear(circ)           ((circ)->head = (circ)->tail = 0)
 347
 348 #define uart_circ_chars_pending(circ)   \
 349         (CIRC_CNT((circ)->head, (circ)->tail, UART_XMIT_SIZE))
 350
 351 #define uart_circ_chars_free(circ)      \
 352         (CIRC_SPACE((circ)->head, (circ)->tail, UART_XMIT_SIZE))
 353
 354 #define uart_tx_stopped(port)           \
 355         ((port)->info->tty->stopped || (port)->info->tty->hw_stopped)
 356
 357 /*
 358  * The following are helper functions for the low level drivers.
 359  */
 360 #ifdef SUPPORT_SYSRQ
 361 static inline int
 362 uart_handle_sysrq_char(struct uart_port *port, unsigned int ch,
 363                        struct pt_regs *regs)
 364 {
 365         if (port->sysrq) {
 366                 if (ch && time_before(jiffies, port->sysrq)) {
 367                         handle_sysrq(ch, regs, NULL);
 368                         port->sysrq = 0;
 369                         return 1;
 370                 }
 371                 port->sysrq = 0;
 372         }
 373         return 0;
 374 }
 375 #else
 376 #define uart_handle_sysrq_char(port,ch,regs)    (0)
 377 #endif
 378
 379 /*
 380  * We do the SysRQ and SAK checking like this...
 381  */
 382 static inline int uart_handle_break(struct uart_port *port)
 383 {
 384         struct uart_info *info = port->info;
 385 #ifdef SUPPORT_SYSRQ
 386         if (port->cons && port->cons->index == port->line) {
 387                 if (!port->sysrq) {
 388                         port->sysrq = jiffies + HZ*5;
 389                         return 1;
 390                 }
 391                 port->sysrq = 0;
 392         }
 393 #endif
 394         if (info->flags & UPF_SAK)
 395                 do_SAK(info->tty);
 396         return 0;
 397 }
 398
 399 /**
 400  *      uart_handle_dcd_change - handle a change of carrier detect state
 401  *      @port: uart_port structure for the open port
 402  *      @status: new carrier detect status, nonzero if active
 403  */
 404 static inline void
 405 uart_handle_dcd_change(struct uart_port *port, unsigned int status)
 406 {
 407         struct uart_info *info = port->info;
 408
 409         port->icount.dcd++;
 410
 411 #ifdef CONFIG_HARD_PPS
 412         if ((port->flags & UPF_HARDPPS_CD) && status)
 413                 hardpps();
 414 #endif
 415
 416         if (info->flags & UIF_CHECK_CD) {
 417                 if (status)
 418                         wake_up_interruptible(&info->open_wait);
 419                 else if (info->tty)
 420                         tty_hangup(info->tty);
 421         }
 422 }
 423
 424 /**
 425  *      uart_handle_cts_change - handle a change of clear-to-send state
 426  *      @port: uart_port structure for the open port
 427  *      @status: new clear to send status, nonzero if active
 428  */
 429 static inline void
 430 uart_handle_cts_change(struct uart_port *port, unsigned int status)
 431 {
 432         struct uart_info *info = port->info;
 433         struct tty_struct *tty = info->tty;
 434
 435         port->icount.cts++;
 436
 437         if (info->flags & UIF_CTS_FLOW) {
 438                 if (tty->hw_stopped) {
 439                         if (status) {
 440                                 tty->hw_stopped = 0;
 441                                 port->ops->start_tx(port, 0);
 442                                 uart_write_wakeup(port);
 443                         }
 444                 } else {
 445                         if (!status) {
 446                                 tty->hw_stopped = 1;
 447                                 port->ops->stop_tx(port, 0);
 448                         }
 449                 }
 450         }
 451 }
 452
 453 /*
 454  *      UART_ENABLE_MS - determine if port should enable modem status irqs
 455  */
 456 #define UART_ENABLE_MS(port,cflag)      ((port)->flags & UPF_HARDPPS_CD || \
 457                                          (cflag) & CRTSCTS || \
 458                                          !((cflag) & CLOCAL))
 459
 460 #endif