1 #ifndef _LINUX_TTY_DRIVER_H 2 #define _LINUX_TTY_DRIVER_H 3 4 /* 5 * This structure defines the interface between the low-level tty 6 * driver and the tty routines. The following routines can be 7 * defined; unless noted otherwise, they are optional, and can be 8 * filled in with a null pointer. 9 * 10 * int (*open)(struct tty_struct * tty, struct file * filp); 11 * 12 * This routine is called when a particular tty device is opened. 13 * This routine is mandatory; if this routine is not filled in, 14 * the attempted open will fail with ENODEV. 15 * 16 * void (*close)(struct tty_struct * tty, struct file * filp); 17 * 18 * This routine is called when a particular tty device is closed. 19 * 20 * int (*write)(struct tty_struct * tty, 21 * const unsigned char *buf, int count); 22 * 23 * This routine is called by the kernel to write a series of 24 * characters to the tty device. The characters may come from 25 * user space or kernel space. This routine will return the 26 * number of characters actually accepted for writing. This 27 * routine is mandatory. 28 * 29 * void (*put_char)(struct tty_struct *tty, unsigned char ch); 30 * 31 * This routine is called by the kernel to write a single 32 * character to the tty device. If the kernel uses this routine, 33 * it must call the flush_chars() routine (if defined) when it is 34 * done stuffing characters into the driver. If there is no room 35 * in the queue, the character is ignored. 36 * 37 * void (*flush_chars)(struct tty_struct *tty); 38 * 39 * This routine is called by the kernel after it has written a 40 * series of characters to the tty device using put_char(). 41 * 42 * int (*write_room)(struct tty_struct *tty); 43 * 44 * This routine returns the numbers of characters the tty driver 45 * will accept for queuing to be written. This number is subject 46 * to change as output buffers get emptied, or if the output flow 47 * control is acted. 48 * 49 * int (*ioctl)(struct tty_struct *tty, struct file * file, 50 * unsigned int cmd, unsigned long arg); 51 * 52 * This routine allows the tty driver to implement 53 * device-specific ioctl's. If the ioctl number passed in cmd 54 * is not recognized by the driver, it should return ENOIOCTLCMD. 55 * 56 * long (*compat_ioctl)(struct tty_struct *tty, struct file * file, 57 * unsigned int cmd, unsigned long arg); 58 * 59 * implement ioctl processing for 32 bit process on 64 bit system 60 * 61 * void (*set_termios)(struct tty_struct *tty, struct ktermios * old); 62 * 63 * This routine allows the tty driver to be notified when 64 * device's termios settings have changed. Note that a 65 * well-designed tty driver should be prepared to accept the case 66 * where old == NULL, and try to do something rational. 67 * 68 * void (*set_ldisc)(struct tty_struct *tty); 69 * 70 * This routine allows the tty driver to be notified when the 71 * device's termios settings have changed. 72 * 73 * void (*throttle)(struct tty_struct * tty); 74 * 75 * This routine notifies the tty driver that input buffers for 76 * the line discipline are close to full, and it should somehow 77 * signal that no more characters should be sent to the tty. 78 * 79 * void (*unthrottle)(struct tty_struct * tty); 80 * 81 * This routine notifies the tty drivers that it should signals 82 * that characters can now be sent to the tty without fear of 83 * overrunning the input buffers of the line disciplines. 84 * 85 * void (*stop)(struct tty_struct *tty); 86 * 87 * This routine notifies the tty driver that it should stop 88 * outputting characters to the tty device. 89 * 90 * void (*start)(struct tty_struct *tty); 91 * 92 * This routine notifies the tty driver that it resume sending 93 * characters to the tty device. 94 * 95 * void (*hangup)(struct tty_struct *tty); 96 * 97 * This routine notifies the tty driver that it should hangup the 98 * tty device. 99 * 100 * void (*break_ctl)(struct tty_stuct *tty, int state); 101 * 102 * This optional routine requests the tty driver to turn on or 103 * off BREAK status on the RS-232 port. If state is -1, 104 * then the BREAK status should be turned on; if state is 0, then 105 * BREAK should be turned off. 106 * 107 * If this routine is implemented, the high-level tty driver will 108 * handle the following ioctls: TCSBRK, TCSBRKP, TIOCSBRK, 109 * TIOCCBRK. Otherwise, these ioctls will be passed down to the 110 * driver to handle. 111 * 112 * void (*wait_until_sent)(struct tty_struct *tty, int timeout); 113 * 114 * This routine waits until the device has written out all of the 115 * characters in its transmitter FIFO. 116 * 117 * void (*send_xchar)(struct tty_struct *tty, char ch); 118 * 119 * This routine is used to send a high-priority XON/XOFF 120 * character to the device. 121 */ 122 123 #include <linux/fs.h> 124 #include <linux/list.h> 125 #include <linux/cdev.h> 126 127 struct tty_struct; 128 129 struct tty_operations { 130 int (*open)(struct tty_struct * tty, struct file * filp); 131 void (*close)(struct tty_struct * tty, struct file * filp); 132 int (*write)(struct tty_struct * tty, 133 const unsigned char *buf, int count); 134 void (*put_char)(struct tty_struct *tty, unsigned char ch); 135 void (*flush_chars)(struct tty_struct *tty); 136 int (*write_room)(struct tty_struct *tty); 137 int (*chars_in_buffer)(struct tty_struct *tty); 138 int (*ioctl)(struct tty_struct *tty, struct file * file, 139 unsigned int cmd, unsigned long arg); 140 long (*compat_ioctl)(struct tty_struct *tty, struct file * file, 141 unsigned int cmd, unsigned long arg); 142 void (*set_termios)(struct tty_struct *tty, struct ktermios * old); 143 void (*throttle)(struct tty_struct * tty); 144 void (*unthrottle)(struct tty_struct * tty); 145 void (*stop)(struct tty_struct *tty); 146 void (*start)(struct tty_struct *tty); 147 void (*hangup)(struct tty_struct *tty); 148 void (*break_ctl)(struct tty_struct *tty, int state); 149 void (*flush_buffer)(struct tty_struct *tty); 150 void (*set_ldisc)(struct tty_struct *tty); 151 void (*wait_until_sent)(struct tty_struct *tty, int timeout); 152 void (*send_xchar)(struct tty_struct *tty, char ch); 153 int (*read_proc)(char *page, char **start, off_t off, 154 int count, int *eof, void *data); 155 int (*write_proc)(struct file *file, const char __user *buffer, 156 unsigned long count, void *data); 157 int (*tiocmget)(struct tty_struct *tty, struct file *file); 158 int (*tiocmset)(struct tty_struct *tty, struct file *file, 159 unsigned int set, unsigned int clear); 160 }; 161 162 struct tty_driver { 163 int magic; /* magic number for this structure */ 164 struct cdev cdev; 165 struct module *owner; 166 const char *driver_name; 167 const char *name; 168 int name_base; /* offset of printed name */ 169 int major; /* major device number */ 170 int minor_start; /* start of minor device number */ 171 int minor_num; /* number of *possible* devices */ 172 int num; /* number of devices allocated */ 173 short type; /* type of tty driver */ 174 short subtype; /* subtype of tty driver */ 175 struct ktermios init_termios; /* Initial termios */ 176 int flags; /* tty driver flags */ 177 int refcount; /* for loadable tty drivers */ 178 struct proc_dir_entry *proc_entry; /* /proc fs entry */ 179 struct tty_driver *other; /* only used for the PTY driver */ 180 181 /* 182 * Pointer to the tty data structures 183 */ 184 struct tty_struct **ttys; 185 struct ktermios **termios; 186 struct ktermios **termios_locked; 187 void *driver_state; /* only used for the PTY driver */ 188 189 /* 190 * Interface routines from the upper tty layer to the tty 191 * driver. Will be replaced with struct tty_operations. 192 */ 193 int (*open)(struct tty_struct * tty, struct file * filp); 194 void (*close)(struct tty_struct * tty, struct file * filp); 195 int (*write)(struct tty_struct * tty, 196 const unsigned char *buf, int count); 197 void (*put_char)(struct tty_struct *tty, unsigned char ch); 198 void (*flush_chars)(struct tty_struct *tty); 199 int (*write_room)(struct tty_struct *tty); 200 int (*chars_in_buffer)(struct tty_struct *tty); 201 int (*ioctl)(struct tty_struct *tty, struct file * file, 202 unsigned int cmd, unsigned long arg); 203 long (*compat_ioctl)(struct tty_struct *tty, struct file * file, 204 unsigned int cmd, unsigned long arg); 205 void (*set_termios)(struct tty_struct *tty, struct ktermios * old); 206 void (*throttle)(struct tty_struct * tty); 207 void (*unthrottle)(struct tty_struct * tty); 208 void (*stop)(struct tty_struct *tty); 209 void (*start)(struct tty_struct *tty); 210 void (*hangup)(struct tty_struct *tty); 211 void (*break_ctl)(struct tty_struct *tty, int state); 212 void (*flush_buffer)(struct tty_struct *tty); 213 void (*set_ldisc)(struct tty_struct *tty); 214 void (*wait_until_sent)(struct tty_struct *tty, int timeout); 215 void (*send_xchar)(struct tty_struct *tty, char ch); 216 int (*read_proc)(char *page, char **start, off_t off, 217 int count, int *eof, void *data); 218 int (*write_proc)(struct file *file, const char __user *buffer, 219 unsigned long count, void *data); 220 int (*tiocmget)(struct tty_struct *tty, struct file *file); 221 int (*tiocmset)(struct tty_struct *tty, struct file *file, 222 unsigned int set, unsigned int clear); 223 224 struct list_head tty_drivers; 225 }; 226 227 extern struct list_head tty_drivers; 228 229 struct tty_driver *alloc_tty_driver(int lines); 230 void put_tty_driver(struct tty_driver *driver); 231 void tty_set_operations(struct tty_driver *driver, 232 const struct tty_operations *op); 233 234 /* tty driver magic number */ 235 #define TTY_DRIVER_MAGIC 0x5402 236 237 /* 238 * tty driver flags 239 * 240 * TTY_DRIVER_RESET_TERMIOS --- requests the tty layer to reset the 241 * termios setting when the last process has closed the device. 242 * Used for PTY's, in particular. 243 * 244 * TTY_DRIVER_REAL_RAW --- if set, indicates that the driver will 245 * guarantee never not to set any special character handling 246 * flags if ((IGNBRK || (!BRKINT && !PARMRK)) && (IGNPAR || 247 * !INPCK)). That is, if there is no reason for the driver to 248 * send notifications of parity and break characters up to the 249 * line driver, it won't do so. This allows the line driver to 250 * optimize for this case if this flag is set. (Note that there 251 * is also a promise, if the above case is true, not to signal 252 * overruns, either.) 253 * 254 * TTY_DRIVER_DYNAMIC_DEV --- if set, the individual tty devices need 255 * to be registered with a call to tty_register_driver() when the 256 * device is found in the system and unregistered with a call to 257 * tty_unregister_device() so the devices will be show up 258 * properly in sysfs. If not set, driver->num entries will be 259 * created by the tty core in sysfs when tty_register_driver() is 260 * called. This is to be used by drivers that have tty devices 261 * that can appear and disappear while the main tty driver is 262 * registered with the tty core. 263 * 264 * TTY_DRIVER_DEVPTS_MEM -- don't use the standard arrays, instead 265 * use dynamic memory keyed through the devpts filesystem. This 266 * is only applicable to the pty driver. 267 */ 268 #define TTY_DRIVER_INSTALLED 0x0001 269 #define TTY_DRIVER_RESET_TERMIOS 0x0002 270 #define TTY_DRIVER_REAL_RAW 0x0004 271 #define TTY_DRIVER_DYNAMIC_DEV 0x0008 272 #define TTY_DRIVER_DEVPTS_MEM 0x0010 273 274 /* tty driver types */ 275 #define TTY_DRIVER_TYPE_SYSTEM 0x0001 276 #define TTY_DRIVER_TYPE_CONSOLE 0x0002 277 #define TTY_DRIVER_TYPE_SERIAL 0x0003 278 #define TTY_DRIVER_TYPE_PTY 0x0004 279 #define TTY_DRIVER_TYPE_SCC 0x0005 /* scc driver */ 280 #define TTY_DRIVER_TYPE_SYSCONS 0x0006 281 282 /* system subtypes (magic, used by tty_io.c) */ 283 #define SYSTEM_TYPE_TTY 0x0001 284 #define SYSTEM_TYPE_CONSOLE 0x0002 285 #define SYSTEM_TYPE_SYSCONS 0x0003 286 #define SYSTEM_TYPE_SYSPTMX 0x0004 287 288 /* pty subtypes (magic, used by tty_io.c) */ 289 #define PTY_TYPE_MASTER 0x0001 290 #define PTY_TYPE_SLAVE 0x0002 291 292 /* serial subtype definitions */ 293 #define SERIAL_TYPE_NORMAL 1 294 295 #endif /* #ifdef _LINUX_TTY_DRIVER_H */ 296