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		2f46a2c1d4
		
	
	
	
	
		
			
			->set_serial() and ->get_serial() resp., both taking tty and a kernel pointer to serial_struct. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
		
			
				
	
	
		
			446 lines
		
	
	
	
		
			16 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			446 lines
		
	
	
	
		
			16 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /* SPDX-License-Identifier: GPL-2.0 */
 | |
| #ifndef _LINUX_TTY_DRIVER_H
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| #define _LINUX_TTY_DRIVER_H
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| 
 | |
| /*
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|  * This structure defines the interface between the low-level tty
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|  * driver and the tty routines.  The following routines can be
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|  * defined; unless noted otherwise, they are optional, and can be
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|  * filled in with a null pointer.
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|  *
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|  * struct tty_struct * (*lookup)(struct tty_driver *self, struct file *, int idx)
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|  *
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|  *	Return the tty device corresponding to idx, NULL if there is not
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|  *	one currently in use and an ERR_PTR value on error. Called under
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|  *	tty_mutex (for now!)
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|  *
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|  *	Optional method. Default behaviour is to use the ttys array
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|  *
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|  * int (*install)(struct tty_driver *self, struct tty_struct *tty)
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|  *
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|  *	Install a new tty into the tty driver internal tables. Used in
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|  *	conjunction with lookup and remove methods.
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|  *
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|  *	Optional method. Default behaviour is to use the ttys array
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|  *
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|  * void (*remove)(struct tty_driver *self, struct tty_struct *tty)
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|  *
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|  *	Remove a closed tty from the tty driver internal tables. Used in
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|  *	conjunction with lookup and remove methods.
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|  *
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|  *	Optional method. Default behaviour is to use the ttys array
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|  *
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|  * int  (*open)(struct tty_struct * tty, struct file * filp);
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|  *
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|  * 	This routine is called when a particular tty device is opened.
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|  * 	This routine is mandatory; if this routine is not filled in,
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|  * 	the attempted open will fail with ENODEV.
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|  *
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|  *	Required method. Called with tty lock held.
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|  *
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|  * void (*close)(struct tty_struct * tty, struct file * filp);
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|  *
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|  * 	This routine is called when a particular tty device is closed.
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|  *	Note: called even if the corresponding open() failed.
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|  *
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|  *	Required method. Called with tty lock held.
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|  *
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|  * void (*shutdown)(struct tty_struct * tty);
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|  *
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|  * 	This routine is called under the tty lock when a particular tty device
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|  *	is closed for the last time. It executes before the tty resources
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|  *	are freed so may execute while another function holds a tty kref.
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|  *
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|  * void (*cleanup)(struct tty_struct * tty);
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|  *
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|  *	This routine is called asynchronously when a particular tty device
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|  *	is closed for the last time freeing up the resources. This is
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|  *	actually the second part of shutdown for routines that might sleep.
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|  *
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|  *
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|  * int (*write)(struct tty_struct * tty,
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|  * 		 const unsigned char *buf, int count);
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|  *
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|  * 	This routine is called by the kernel to write a series of
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|  * 	characters to the tty device.  The characters may come from
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|  * 	user space or kernel space.  This routine will return the
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|  *	number of characters actually accepted for writing.
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|  *
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|  *	Optional: Required for writable devices.
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|  *
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|  * int (*put_char)(struct tty_struct *tty, unsigned char ch);
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|  *
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|  * 	This routine is called by the kernel to write a single
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|  * 	character to the tty device.  If the kernel uses this routine,
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|  * 	it must call the flush_chars() routine (if defined) when it is
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|  * 	done stuffing characters into the driver.  If there is no room
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|  * 	in the queue, the character is ignored.
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|  *
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|  *	Optional: Kernel will use the write method if not provided.
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|  *
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|  *	Note: Do not call this function directly, call tty_put_char
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|  *
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|  * void (*flush_chars)(struct tty_struct *tty);
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|  *
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|  * 	This routine is called by the kernel after it has written a
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|  * 	series of characters to the tty device using put_char().  
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|  *
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|  *	Optional:
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|  *
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|  *	Note: Do not call this function directly, call tty_driver_flush_chars
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|  * 
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|  * int  (*write_room)(struct tty_struct *tty);
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|  *
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|  * 	This routine returns the numbers of characters the tty driver
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|  * 	will accept for queuing to be written.  This number is subject
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|  * 	to change as output buffers get emptied, or if the output flow
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|  *	control is acted.
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|  *
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|  *	Required if write method is provided else not needed.
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|  *
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|  *	Note: Do not call this function directly, call tty_write_room
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|  * 
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|  * int  (*ioctl)(struct tty_struct *tty, unsigned int cmd, unsigned long arg);
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|  *
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|  * 	This routine allows the tty driver to implement
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|  *	device-specific ioctls.  If the ioctl number passed in cmd
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|  * 	is not recognized by the driver, it should return ENOIOCTLCMD.
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|  *
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|  *	Optional
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|  *
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|  * long (*compat_ioctl)(struct tty_struct *tty,,
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|  * 	                unsigned int cmd, unsigned long arg);
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|  *
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|  * 	implement ioctl processing for 32 bit process on 64 bit system
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|  *
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|  *	Optional
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|  * 
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|  * void (*set_termios)(struct tty_struct *tty, struct ktermios * old);
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|  *
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|  * 	This routine allows the tty driver to be notified when
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|  * 	device's termios settings have changed.
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|  *
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|  *	Optional: Called under the termios lock
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|  *
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|  *
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|  * void (*set_ldisc)(struct tty_struct *tty);
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|  *
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|  * 	This routine allows the tty driver to be notified when the
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|  * 	device's termios settings have changed.
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|  *
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|  *	Optional: Called under BKL (currently)
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|  * 
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|  * void (*throttle)(struct tty_struct * tty);
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|  *
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|  * 	This routine notifies the tty driver that input buffers for
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|  * 	the line discipline are close to full, and it should somehow
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|  * 	signal that no more characters should be sent to the tty.
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|  *
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|  *	Optional: Always invoke via tty_throttle(), called under the
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|  *	termios lock.
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|  * 
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|  * void (*unthrottle)(struct tty_struct * tty);
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|  *
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|  * 	This routine notifies the tty drivers that it should signals
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|  * 	that characters can now be sent to the tty without fear of
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|  * 	overrunning the input buffers of the line disciplines.
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|  * 
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|  *	Optional: Always invoke via tty_unthrottle(), called under the
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|  *	termios lock.
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|  *
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|  * void (*stop)(struct tty_struct *tty);
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|  *
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|  * 	This routine notifies the tty driver that it should stop
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|  * 	outputting characters to the tty device.  
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|  *
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|  *	Called with ->flow_lock held. Serialized with start() method.
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|  *
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|  *	Optional:
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|  *
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|  *	Note: Call stop_tty not this method.
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|  * 
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|  * void (*start)(struct tty_struct *tty);
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|  *
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|  * 	This routine notifies the tty driver that it resume sending
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|  *	characters to the tty device.
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|  *
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|  *	Called with ->flow_lock held. Serialized with stop() method.
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|  *
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|  *	Optional:
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|  *
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|  *	Note: Call start_tty not this method.
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|  * 
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|  * void (*hangup)(struct tty_struct *tty);
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|  *
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|  * 	This routine notifies the tty driver that it should hang up the
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|  * 	tty device.
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|  *
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|  *	Optional:
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|  *
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|  *	Called with tty lock held.
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|  *
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|  * int (*break_ctl)(struct tty_struct *tty, int state);
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|  *
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|  * 	This optional routine requests the tty driver to turn on or
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|  * 	off BREAK status on the RS-232 port.  If state is -1,
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|  * 	then the BREAK status should be turned on; if state is 0, then
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|  * 	BREAK should be turned off.
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|  *
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|  * 	If this routine is implemented, the high-level tty driver will
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|  * 	handle the following ioctls: TCSBRK, TCSBRKP, TIOCSBRK,
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|  * 	TIOCCBRK.
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|  *
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|  *	If the driver sets TTY_DRIVER_HARDWARE_BREAK then the interface
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|  *	will also be called with actual times and the hardware is expected
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|  *	to do the delay work itself. 0 and -1 are still used for on/off.
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|  *
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|  *	Optional: Required for TCSBRK/BRKP/etc handling.
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|  *
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|  * void (*wait_until_sent)(struct tty_struct *tty, int timeout);
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|  * 
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|  * 	This routine waits until the device has written out all of the
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|  * 	characters in its transmitter FIFO.
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|  *
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|  *	Optional: If not provided the device is assumed to have no FIFO
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|  *
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|  *	Note: Usually correct to call tty_wait_until_sent
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|  *
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|  * void (*send_xchar)(struct tty_struct *tty, char ch);
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|  *
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|  * 	This routine is used to send a high-priority XON/XOFF
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|  * 	character to the device.
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|  *
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|  *	Optional: If not provided then the write method is called under
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|  *	the atomic write lock to keep it serialized with the ldisc.
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|  *
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|  * int (*resize)(struct tty_struct *tty, struct winsize *ws)
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|  *
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|  *	Called when a termios request is issued which changes the
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|  *	requested terminal geometry.
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|  *
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|  *	Optional: the default action is to update the termios structure
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|  *	without error. This is usually the correct behaviour. Drivers should
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|  *	not force errors here if they are not resizable objects (eg a serial
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|  *	line). See tty_do_resize() if you need to wrap the standard method
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|  *	in your own logic - the usual case.
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|  *
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|  * void (*set_termiox)(struct tty_struct *tty, struct termiox *new);
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|  *
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|  *	Called when the device receives a termiox based ioctl. Passes down
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|  *	the requested data from user space. This method will not be invoked
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|  *	unless the tty also has a valid tty->termiox pointer.
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|  *
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|  *	Optional: Called under the termios lock
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|  *
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|  * int (*get_icount)(struct tty_struct *tty, struct serial_icounter *icount);
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|  *
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|  *	Called when the device receives a TIOCGICOUNT ioctl. Passed a kernel
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|  *	structure to complete. This method is optional and will only be called
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|  *	if provided (otherwise EINVAL will be returned).
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|  */
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| 
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| #include <linux/export.h>
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| #include <linux/fs.h>
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| #include <linux/list.h>
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| #include <linux/cdev.h>
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| #include <linux/termios.h>
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| #include <linux/seq_file.h>
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| 
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| struct tty_struct;
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| struct tty_driver;
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| struct serial_icounter_struct;
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| struct serial_struct;
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| 
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| struct tty_operations {
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| 	struct tty_struct * (*lookup)(struct tty_driver *driver,
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| 			struct file *filp, int idx);
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| 	int  (*install)(struct tty_driver *driver, struct tty_struct *tty);
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| 	void (*remove)(struct tty_driver *driver, struct tty_struct *tty);
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| 	int  (*open)(struct tty_struct * tty, struct file * filp);
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| 	void (*close)(struct tty_struct * tty, struct file * filp);
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| 	void (*shutdown)(struct tty_struct *tty);
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| 	void (*cleanup)(struct tty_struct *tty);
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| 	int  (*write)(struct tty_struct * tty,
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| 		      const unsigned char *buf, int count);
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| 	int  (*put_char)(struct tty_struct *tty, unsigned char ch);
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| 	void (*flush_chars)(struct tty_struct *tty);
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| 	int  (*write_room)(struct tty_struct *tty);
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| 	int  (*chars_in_buffer)(struct tty_struct *tty);
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| 	int  (*ioctl)(struct tty_struct *tty,
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| 		    unsigned int cmd, unsigned long arg);
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| 	long (*compat_ioctl)(struct tty_struct *tty,
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| 			     unsigned int cmd, unsigned long arg);
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| 	void (*set_termios)(struct tty_struct *tty, struct ktermios * old);
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| 	void (*throttle)(struct tty_struct * tty);
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| 	void (*unthrottle)(struct tty_struct * tty);
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| 	void (*stop)(struct tty_struct *tty);
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| 	void (*start)(struct tty_struct *tty);
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| 	void (*hangup)(struct tty_struct *tty);
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| 	int (*break_ctl)(struct tty_struct *tty, int state);
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| 	void (*flush_buffer)(struct tty_struct *tty);
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| 	void (*set_ldisc)(struct tty_struct *tty);
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| 	void (*wait_until_sent)(struct tty_struct *tty, int timeout);
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| 	void (*send_xchar)(struct tty_struct *tty, char ch);
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| 	int (*tiocmget)(struct tty_struct *tty);
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| 	int (*tiocmset)(struct tty_struct *tty,
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| 			unsigned int set, unsigned int clear);
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| 	int (*resize)(struct tty_struct *tty, struct winsize *ws);
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| 	int (*set_termiox)(struct tty_struct *tty, struct termiox *tnew);
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| 	int (*get_icount)(struct tty_struct *tty,
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| 				struct serial_icounter_struct *icount);
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| 	int  (*get_serial)(struct tty_struct *tty, struct serial_struct *p);
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| 	int  (*set_serial)(struct tty_struct *tty, struct serial_struct *p);
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| 	void (*show_fdinfo)(struct tty_struct *tty, struct seq_file *m);
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| #ifdef CONFIG_CONSOLE_POLL
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| 	int (*poll_init)(struct tty_driver *driver, int line, char *options);
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| 	int (*poll_get_char)(struct tty_driver *driver, int line);
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| 	void (*poll_put_char)(struct tty_driver *driver, int line, char ch);
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| #endif
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| 	int (*proc_show)(struct seq_file *, void *);
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| } __randomize_layout;
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| 
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| struct tty_driver {
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| 	int	magic;		/* magic number for this structure */
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| 	struct kref kref;	/* Reference management */
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| 	struct cdev **cdevs;
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| 	struct module	*owner;
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| 	const char	*driver_name;
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| 	const char	*name;
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| 	int	name_base;	/* offset of printed name */
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| 	int	major;		/* major device number */
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| 	int	minor_start;	/* start of minor device number */
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| 	unsigned int	num;	/* number of devices allocated */
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| 	short	type;		/* type of tty driver */
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| 	short	subtype;	/* subtype of tty driver */
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| 	struct ktermios init_termios; /* Initial termios */
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| 	unsigned long	flags;		/* tty driver flags */
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| 	struct proc_dir_entry *proc_entry; /* /proc fs entry */
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| 	struct tty_driver *other; /* only used for the PTY driver */
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| 
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| 	/*
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| 	 * Pointer to the tty data structures
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| 	 */
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| 	struct tty_struct **ttys;
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| 	struct tty_port **ports;
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| 	struct ktermios **termios;
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| 	void *driver_state;
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| 
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| 	/*
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| 	 * Driver methods
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| 	 */
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| 
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| 	const struct tty_operations *ops;
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| 	struct list_head tty_drivers;
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| } __randomize_layout;
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| 
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| extern struct list_head tty_drivers;
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| 
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| extern struct tty_driver *__tty_alloc_driver(unsigned int lines,
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| 		struct module *owner, unsigned long flags);
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| extern void put_tty_driver(struct tty_driver *driver);
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| extern void tty_set_operations(struct tty_driver *driver,
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| 			const struct tty_operations *op);
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| extern struct tty_driver *tty_find_polling_driver(char *name, int *line);
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| 
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| extern void tty_driver_kref_put(struct tty_driver *driver);
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| 
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| /* Use TTY_DRIVER_* flags below */
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| #define tty_alloc_driver(lines, flags) \
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| 		__tty_alloc_driver(lines, THIS_MODULE, flags)
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| 
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| /*
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|  * DEPRECATED Do not use this in new code, use tty_alloc_driver instead.
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|  * (And change the return value checks.)
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|  */
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| static inline struct tty_driver *alloc_tty_driver(unsigned int lines)
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| {
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| 	struct tty_driver *ret = tty_alloc_driver(lines, 0);
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| 	if (IS_ERR(ret))
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| 		return NULL;
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| 	return ret;
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| }
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| 
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| static inline struct tty_driver *tty_driver_kref_get(struct tty_driver *d)
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| {
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| 	kref_get(&d->kref);
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| 	return d;
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| }
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| 
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| /* tty driver magic number */
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| #define TTY_DRIVER_MAGIC		0x5402
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| 
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| /*
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|  * tty driver flags
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|  * 
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|  * TTY_DRIVER_RESET_TERMIOS --- requests the tty layer to reset the
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|  * 	termios setting when the last process has closed the device.
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|  * 	Used for PTY's, in particular.
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|  * 
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|  * TTY_DRIVER_REAL_RAW --- if set, indicates that the driver will
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|  * 	guarantee never not to set any special character handling
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|  * 	flags if ((IGNBRK || (!BRKINT && !PARMRK)) && (IGNPAR ||
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|  * 	!INPCK)).  That is, if there is no reason for the driver to
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|  * 	send notifications of parity and break characters up to the
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|  * 	line driver, it won't do so.  This allows the line driver to
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|  *	optimize for this case if this flag is set.  (Note that there
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|  * 	is also a promise, if the above case is true, not to signal
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|  * 	overruns, either.)
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|  *
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|  * TTY_DRIVER_DYNAMIC_DEV --- if set, the individual tty devices need
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|  *	to be registered with a call to tty_register_device() when the
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|  *	device is found in the system and unregistered with a call to
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|  *	tty_unregister_device() so the devices will be show up
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|  *	properly in sysfs.  If not set, driver->num entries will be
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|  *	created by the tty core in sysfs when tty_register_driver() is
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|  *	called.  This is to be used by drivers that have tty devices
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|  *	that can appear and disappear while the main tty driver is
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|  *	registered with the tty core.
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|  *
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|  * TTY_DRIVER_DEVPTS_MEM -- don't use the standard arrays, instead
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|  *	use dynamic memory keyed through the devpts filesystem.  This
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|  *	is only applicable to the pty driver.
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|  *
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|  * TTY_DRIVER_HARDWARE_BREAK -- hardware handles break signals. Pass
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|  *	the requested timeout to the caller instead of using a simple
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|  *	on/off interface.
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|  *
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|  * TTY_DRIVER_DYNAMIC_ALLOC -- do not allocate structures which are
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|  *	needed per line for this driver as it would waste memory.
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|  *	The driver will take care.
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|  *
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|  * TTY_DRIVER_UNNUMBERED_NODE -- do not create numbered /dev nodes. In
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|  *	other words create /dev/ttyprintk and not /dev/ttyprintk0.
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|  *	Applicable only when a driver for a single tty device is
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|  *	being allocated.
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|  */
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| #define TTY_DRIVER_INSTALLED		0x0001
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| #define TTY_DRIVER_RESET_TERMIOS	0x0002
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| #define TTY_DRIVER_REAL_RAW		0x0004
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| #define TTY_DRIVER_DYNAMIC_DEV		0x0008
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| #define TTY_DRIVER_DEVPTS_MEM		0x0010
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| #define TTY_DRIVER_HARDWARE_BREAK	0x0020
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| #define TTY_DRIVER_DYNAMIC_ALLOC	0x0040
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| #define TTY_DRIVER_UNNUMBERED_NODE	0x0080
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| 
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| /* tty driver types */
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| #define TTY_DRIVER_TYPE_SYSTEM		0x0001
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| #define TTY_DRIVER_TYPE_CONSOLE		0x0002
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| #define TTY_DRIVER_TYPE_SERIAL		0x0003
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| #define TTY_DRIVER_TYPE_PTY		0x0004
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| #define TTY_DRIVER_TYPE_SCC		0x0005	/* scc driver */
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| #define TTY_DRIVER_TYPE_SYSCONS		0x0006
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| 
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| /* system subtypes (magic, used by tty_io.c) */
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| #define SYSTEM_TYPE_TTY			0x0001
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| #define SYSTEM_TYPE_CONSOLE		0x0002
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| #define SYSTEM_TYPE_SYSCONS		0x0003
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| #define SYSTEM_TYPE_SYSPTMX		0x0004
 | |
| 
 | |
| /* pty subtypes (magic, used by tty_io.c) */
 | |
| #define PTY_TYPE_MASTER			0x0001
 | |
| #define PTY_TYPE_SLAVE			0x0002
 | |
| 
 | |
| /* serial subtype definitions */
 | |
| #define SERIAL_TYPE_NORMAL	1
 | |
| 
 | |
| #endif /* #ifdef _LINUX_TTY_DRIVER_H */
 |