* defined; unless noted otherwise, they are optional, and can be
* filled in with a null pointer.
*
+ * struct tty_struct * (*lookup)(struct tty_driver *self, int idx)
+ *
+ * Return the tty device corresponding to idx, NULL if there is not
+ * one currently in use and an ERR_PTR value on error. Called under
+ * tty_mutex (for now!)
+ *
+ * Optional method. Default behaviour is to use the ttys array
+ *
+ * int (*install)(struct tty_driver *self, struct tty_struct *tty)
+ *
+ * Install a new tty into the tty driver internal tables. Used in
+ * conjunction with lookup and remove methods.
+ *
+ * Optional method. Default behaviour is to use the ttys array
+ *
+ * void (*remove)(struct tty_driver *self, struct tty_struct *tty)
+ *
+ * Remove a closed tty from the tty driver internal tables. Used in
+ * conjunction with lookup and remove methods.
+ *
+ * Optional method. Default behaviour is to use the ttys array
+ *
* int (*open)(struct tty_struct * tty, struct file * filp);
*
* This routine is called when a particular tty device is opened.
*
* Required method.
*
+ * void (*shutdown)(struct tty_struct * tty);
+ *
+ * This routine is called synchronously when a particular tty device
+ * is closed for the last time freeing up the resources.
+ *
+ *
+ * void (*cleanup)(struct tty_struct * tty);
+ *
+ * This routine is called asynchronously when a particular tty device
+ * is closed for the last time freeing up the resources. This is
+ * actually the second part of shutdown for routines that might sleep.
+ *
+ *
* int (*write)(struct tty_struct * tty,
* 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.
+ * number of characters actually accepted for writing.
*
* Optional: Required for writable devices.
*
* the line discipline are close to full, and it should somehow
* signal that no more characters should be sent to the tty.
*
- * Optional: Always invoke via tty_throttle();
+ * Optional: Always invoke via tty_throttle(), called under the
+ * termios lock.
*
* void (*unthrottle)(struct tty_struct * tty);
*
* that characters can now be sent to the tty without fear of
* overrunning the input buffers of the line disciplines.
*
- * Optional: Always invoke via tty_unthrottle();
+ * Optional: Always invoke via tty_unthrottle(), called under the
+ * termios lock.
*
* void (*stop)(struct tty_struct *tty);
*
* This routine notifies the tty driver that it should hangup the
* tty device.
*
- * Required:
+ * Optional:
*
- * void (*break_ctl)(struct tty_stuct *tty, int state);
+ * int (*break_ctl)(struct tty_stuct *tty, int state);
*
* This optional routine requests the tty driver to turn on or
* off BREAK status on the RS-232 port. If state is -1,
* handle the following ioctls: TCSBRK, TCSBRKP, TIOCSBRK,
* TIOCCBRK.
*
+ * If the driver sets TTY_DRIVER_HARDWARE_BREAK then the interface
+ * will also be called with actual times and the hardware is expected
+ * to do the delay work itself. 0 and -1 are still used for on/off.
+ *
* Optional: Required for TCSBRK/BRKP/etc handling.
*
* void (*wait_until_sent)(struct tty_struct *tty, int timeout);
*
* Optional: If not provided then the write method is called under
* the atomic write lock to keep it serialized with the ldisc.
+ *
+ * int (*resize)(struct tty_struct *tty, struct winsize *ws)
+ *
+ * Called when a termios request is issued which changes the
+ * requested terminal geometry.
+ *
+ * Optional: the default action is to update the termios structure
+ * without error. This is usually the correct behaviour. Drivers should
+ * not force errors here if they are not resizable objects (eg a serial
+ * line). See tty_do_resize() if you need to wrap the standard method
+ * in your own logic - the usual case.
+ *
+ * void (*set_termiox)(struct tty_struct *tty, struct termiox *new);
+ *
+ * Called when the device receives a termiox based ioctl. Passes down
+ * the requested data from user space. This method will not be invoked
+ * unless the tty also has a valid tty->termiox pointer.
+ *
+ * Optional: Called under the termios lock
*/
#include <linux/fs.h>
struct tty_driver;
struct tty_operations {
+ struct tty_struct * (*lookup)(struct tty_driver *driver,
+ struct inode *inode, int idx);
+ int (*install)(struct tty_driver *driver, struct tty_struct *tty);
+ void (*remove)(struct tty_driver *driver, struct tty_struct *tty);
int (*open)(struct tty_struct * tty, struct file * filp);
void (*close)(struct tty_struct * tty, struct file * filp);
+ void (*shutdown)(struct tty_struct *tty);
+ void (*cleanup)(struct tty_struct *tty);
int (*write)(struct tty_struct * tty,
const unsigned char *buf, int count);
int (*put_char)(struct tty_struct *tty, unsigned char ch);
void (*stop)(struct tty_struct *tty);
void (*start)(struct tty_struct *tty);
void (*hangup)(struct tty_struct *tty);
- void (*break_ctl)(struct tty_struct *tty, int state);
+ int (*break_ctl)(struct tty_struct *tty, int state);
void (*flush_buffer)(struct tty_struct *tty);
void (*set_ldisc)(struct tty_struct *tty);
void (*wait_until_sent)(struct tty_struct *tty, int timeout);
void (*send_xchar)(struct tty_struct *tty, char ch);
- int (*read_proc)(char *page, char **start, off_t off,
- int count, int *eof, void *data);
int (*tiocmget)(struct tty_struct *tty, struct file *file);
int (*tiocmset)(struct tty_struct *tty, struct file *file,
unsigned int set, unsigned int clear);
+ int (*resize)(struct tty_struct *tty, struct winsize *ws);
+ int (*set_termiox)(struct tty_struct *tty, struct termiox *tnew);
#ifdef CONFIG_CONSOLE_POLL
int (*poll_init)(struct tty_driver *driver, int line, char *options);
int (*poll_get_char)(struct tty_driver *driver, int line);
void (*poll_put_char)(struct tty_driver *driver, int line, char ch);
#endif
+ const struct file_operations *proc_fops;
};
struct tty_driver {
int magic; /* magic number for this structure */
+ struct kref kref; /* Reference management */
struct cdev cdev;
struct module *owner;
const char *driver_name;
short subtype; /* subtype of tty driver */
struct ktermios init_termios; /* Initial termios */
int flags; /* tty driver flags */
- int refcount; /* for loadable tty drivers */
struct proc_dir_entry *proc_entry; /* /proc fs entry */
struct tty_driver *other; /* only used for the PTY driver */
extern struct list_head tty_drivers;
-struct tty_driver *alloc_tty_driver(int lines);
-void put_tty_driver(struct tty_driver *driver);
-void tty_set_operations(struct tty_driver *driver,
+extern struct tty_driver *alloc_tty_driver(int lines);
+extern void put_tty_driver(struct tty_driver *driver);
+extern void tty_set_operations(struct tty_driver *driver,
const struct tty_operations *op);
extern struct tty_driver *tty_find_polling_driver(char *name, int *line);
+extern void tty_driver_kref_put(struct tty_driver *driver);
+
+static inline struct tty_driver *tty_driver_kref_get(struct tty_driver *d)
+{
+ kref_get(&d->kref);
+ return d;
+}
+
/* tty driver magic number */
#define TTY_DRIVER_MAGIC 0x5402
* TTY_DRIVER_DEVPTS_MEM -- don't use the standard arrays, instead
* use dynamic memory keyed through the devpts filesystem. This
* is only applicable to the pty driver.
+ *
+ * TTY_DRIVER_HARDWARE_BREAK -- hardware handles break signals. Pass
+ * the requested timeout to the caller instead of using a simple
+ * on/off interface.
+ *
*/
#define TTY_DRIVER_INSTALLED 0x0001
#define TTY_DRIVER_RESET_TERMIOS 0x0002
#define TTY_DRIVER_REAL_RAW 0x0004
#define TTY_DRIVER_DYNAMIC_DEV 0x0008
#define TTY_DRIVER_DEVPTS_MEM 0x0010
+#define TTY_DRIVER_HARDWARE_BREAK 0x0020
/* tty driver types */
#define TTY_DRIVER_TYPE_SYSTEM 0x0001