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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 | #ifndef _LINUX_TTY_DRIVER_H #define _LINUX_TTY_DRIVER_H /* * This structure defines the interface between the low-level tty * driver and the tty routines. The following routines can be * defined; unless noted otherwise, they are optional, and can be * filled in with a null pointer. * * int (*open)(struct tty_struct * tty, struct file * filp); * * This routine is called when a particular tty device is opened. * This routine is mandatory; if this routine is not filled in, * the attempted open will fail with ENODEV. * * void (*close)(struct tty_struct * tty, struct file * filp); * * This routine is called when a particular tty device is closed. * * int (*write)(struct tty_struct * tty, int from_user, * const unsigned char *buf, int count); * * This routine is called by the kernel to write a series of * characters to the tty device. The characters may come from * user space or kernel space. This routine will return the * number of characters actually accepted for writing. This * routine is mandatory. * * void (*put_char)(struct tty_struct *tty, unsigned char ch); * * This routine is called by the kernel to write a single * character to the tty device. If the kernel uses this routine, * it must call the flush_chars() routine (if defined) when it is * done stuffing characters into the driver. If there is no room * in the queue, the character is ignored. * * void (*flush_chars)(struct tty_struct *tty); * * This routine is called by the kernel after it has written a * series of characters to the tty device using put_char(). * * int (*write_room)(struct tty_struct *tty); * * This routine returns the numbers of characters the tty driver * will accept for queuing to be written. This number is subject * to change as output buffers get emptied, or if the output flow * control is acted. * * int (*ioctl)(struct tty_struct *tty, struct file * file, * unsigned int cmd, unsigned long arg); * * This routine allows the tty driver to implement * device-specific ioctl's. If the ioctl number passed in cmd * is not recognized by the driver, it should return ENOIOCTLCMD. * * void (*set_termios)(struct tty_struct *tty, struct termios * old); * * This routine allows the tty driver to be notified when * device's termios settings have changed. Note that a * well-designed tty driver should be prepared to accept the case * where old == NULL, and try to do something rational. * * void (*set_ldisc)(struct tty_struct *tty); * * This routine allows the tty driver to be notified when the * device's termios settings have changed. * * void (*throttle)(struct tty_struct * tty); * * This routine notifies the tty driver that input buffers for * the line discipline are close to full, and it should somehow * signal that no more characters should be sent to the tty. * * void (*unthrottle)(struct tty_struct * tty); * * This routine notifies the tty drivers that it should signals * that characters can now be sent to the tty without fear of * overrunning the input buffers of the line disciplines. * * void (*stop)(struct tty_struct *tty); * * This routine notifies the tty driver that it should stop * outputting characters to the tty device. * * void (*start)(struct tty_struct *tty); * * This routine notifies the tty driver that it resume sending * characters to the tty device. * * void (*hangup)(struct tty_struct *tty); * * This routine notifies the tty driver that it should hangup the * tty device. * */ #include <linux/fs.h> struct tty_driver { int magic; /* magic number for this structure */ const char *name; int name_base; /* offset of printed name */ short major; /* major device number */ short minor_start; /* start of minor device number*/ short num; /* number of devices */ short type; /* type of tty driver */ short subtype; /* subtype of tty driver */ struct termios init_termios; /* Initial termios */ int flags; /* tty driver flags */ int *refcount; /* for loadable tty drivers */ struct tty_driver *other; /* only used for the PTY driver */ /* * Pointer to the tty data structures */ struct tty_struct **table; struct termios **termios; struct termios **termios_locked; /* * Interface routines from the upper tty layer to the tty * driver. */ int (*open)(struct tty_struct * tty, struct file * filp); void (*close)(struct tty_struct * tty, struct file * filp); int (*write)(struct tty_struct * tty, int from_user, const unsigned char *buf, int count); void (*put_char)(struct tty_struct *tty, unsigned char ch); void (*flush_chars)(struct tty_struct *tty); int (*write_room)(struct tty_struct *tty); int (*chars_in_buffer)(struct tty_struct *tty); int (*ioctl)(struct tty_struct *tty, struct file * file, unsigned int cmd, unsigned long arg); void (*set_termios)(struct tty_struct *tty, struct termios * old); void (*throttle)(struct tty_struct * tty); void (*unthrottle)(struct tty_struct * tty); void (*stop)(struct tty_struct *tty); void (*start)(struct tty_struct *tty); void (*hangup)(struct tty_struct *tty); void (*flush_buffer)(struct tty_struct *tty); void (*set_ldisc)(struct tty_struct *tty); /* * linked list pointers */ struct tty_driver *next; struct tty_driver *prev; }; /* tty driver magic number */ #define TTY_DRIVER_MAGIC 0x5402 /* * tty driver flags * * TTY_DRIVER_RESET_TERMIOS --- requests the tty layer to reset the * termios setting when the last process has closed the device. * Used for PTY's, in particular. * * TTY_DRIVER_REAL_RAW --- if set, indicates that the driver will * guarantee never not to set any special character handling * flags if ((IGNBRK || (!BRKINT && !PARMRK)) && (IGNPAR || * !INPCK)). That is, if there is no reason for the driver to * send notifications of parity and break characters up to the * line driver, it won't do so. This allows the line driver to * optimize for this case if this flag is set. (Note that there * is also a promise, if the above case is true, not to signal * overruns, either.) */ #define TTY_DRIVER_INSTALLED 0x0001 #define TTY_DRIVER_RESET_TERMIOS 0x0002 #define TTY_DRIVER_REAL_RAW 0x0004 /* tty driver types */ #define TTY_DRIVER_TYPE_SYSTEM 0x0001 #define TTY_DRIVER_TYPE_CONSOLE 0x0002 #define TTY_DRIVER_TYPE_SERIAL 0x0003 #define TTY_DRIVER_TYPE_PTY 0x0004 #define TTY_DRIVER_TYPE_SCC 0x0005 /* scc driver */ /* system subtypes (magic, used by tty_io.c) */ #define SYSTEM_TYPE_TTY 0x0001 #define SYSTEM_TYPE_CONSOLE 0x0002 /* pty subtypes (magic, used by tty_io.c) */ #define PTY_TYPE_MASTER 0x0001 #define PTY_TYPE_SLAVE 0x0002 #endif /* #ifdef _LINUX_TTY_DRIVER_H */ |