/*
   * USB Serial Converter stuff
   *
   *	Copyright (C) 1999 - 2012
   *	    Greg Kroah-Hartman (greg@kroah.com)
   *
   *	This program is free software; you can redistribute it and/or modify
   *	it under the terms of the GNU General Public License as published by
   *	the Free Software Foundation; version 2 of the License.
   *
   */
  
  #ifndef __LINUX_USB_SERIAL_H
  #define __LINUX_USB_SERIAL_H
  
  #include <linux/kref.h>
  #include <linux/mutex.h>
  #include <linux/serial.h>
  #include <linux/sysrq.h>
  #include <linux/kfifo.h>
  
  /* The maximum number of ports one device can grab at once */
  #define MAX_NUM_PORTS		8
  
  /* parity check flag */
  #define RELEVANT_IFLAG(iflag)	(iflag & (IGNBRK|BRKINT|IGNPAR|PARMRK|INPCK))
  
  /* USB serial flags */
  #define USB_SERIAL_WRITE_BUSY	0
  
  /**
   * usb_serial_port: structure for the specific ports of a device.
   * @serial: pointer back to the struct usb_serial owner of this port.
   * @port: pointer to the corresponding tty_port for this port.
   * @lock: spinlock to grab when updating portions of this structure.
   * @minor: the minor number of the port
   * @port_number: the struct usb_serial port number of this port (starts at 0)
   * @interrupt_in_buffer: pointer to the interrupt in buffer for this port.
   * @interrupt_in_urb: pointer to the interrupt in struct urb for this port.
   * @interrupt_in_endpointAddress: endpoint address for the interrupt in pipe
   *	for this port.
   * @interrupt_out_buffer: pointer to the interrupt out buffer for this port.
   * @interrupt_out_size: the size of the interrupt_out_buffer, in bytes.
   * @interrupt_out_urb: pointer to the interrupt out struct urb for this port.
   * @interrupt_out_endpointAddress: endpoint address for the interrupt out pipe
   *	for this port.
   * @bulk_in_buffer: pointer to the bulk in buffer for this port.
   * @bulk_in_size: the size of the bulk_in_buffer, in bytes.
   * @read_urb: pointer to the bulk in struct urb for this port.
   * @bulk_in_endpointAddress: endpoint address for the bulk in pipe for this
   *	port.
   * @bulk_in_buffers: pointers to the bulk in buffers for this port
   * @read_urbs: pointers to the bulk in urbs for this port
   * @read_urbs_free: status bitmap the for bulk in urbs
   * @bulk_out_buffer: pointer to the bulk out buffer for this port.
   * @bulk_out_size: the size of the bulk_out_buffer, in bytes.
   * @write_urb: pointer to the bulk out struct urb for this port.
   * @write_fifo: kfifo used to buffer outgoing data
   * @bulk_out_buffers: pointers to the bulk out buffers for this port
   * @write_urbs: pointers to the bulk out urbs for this port
   * @write_urbs_free: status bitmap the for bulk out urbs
   * @icount: interrupt counters
   * @tx_bytes: number of bytes currently in host stack queues
   * @bulk_out_endpointAddress: endpoint address for the bulk out pipe for this
   *	port.
   * @flags: usb serial port flags
   * @write_wait: a wait_queue_head_t used by the port.
   * @work: work queue entry for the line discipline waking up.
   * @throttled: nonzero if the read urb is inactive to throttle the device
   * @throttle_req: nonzero if the tty wants to throttle us
   * @dev: pointer to the serial device
   *
   * This structure is used by the usb-serial core and drivers for the specific
   * ports of a device.
   */
  struct usb_serial_port {
  	struct usb_serial	*serial;
  	struct tty_port		port;
  	spinlock_t		lock;
  	u32			minor;
  	u8			port_number;
  
  	unsigned char		*interrupt_in_buffer;
  	struct urb		*interrupt_in_urb;
  	__u8			interrupt_in_endpointAddress;
  
  	unsigned char		*interrupt_out_buffer;
  	int			interrupt_out_size;
  	struct urb		*interrupt_out_urb;
  	__u8			interrupt_out_endpointAddress;
  
  	unsigned char		*bulk_in_buffer;
  	int			bulk_in_size;
  	struct urb		*read_urb;
  	__u8			bulk_in_endpointAddress;
  
  	unsigned char		*bulk_in_buffers[2];
  	struct urb		*read_urbs[2];
  	unsigned long		read_urbs_free;
  
  	unsigned char		*bulk_out_buffer;
  	int			bulk_out_size;
  	struct urb		*write_urb;
  	struct kfifo		write_fifo;
  
  	unsigned char		*bulk_out_buffers[2];
  	struct urb		*write_urbs[2];
  	unsigned long		write_urbs_free;
  	__u8			bulk_out_endpointAddress;
  
  	struct async_icount	icount;
  	int			tx_bytes;
  
  	unsigned long		flags;
  	wait_queue_head_t	write_wait;
  	struct work_struct	work;
  	char			throttled;
  	char			throttle_req;
  	unsigned long		sysrq; /* sysrq timeout */
  	struct device		dev;
  };
  #define to_usb_serial_port(d) container_of(d, struct usb_serial_port, dev)
  
  /* get and set the port private data pointer helper functions */
  static inline void *usb_get_serial_port_data(struct usb_serial_port *port)
  {
  	return dev_get_drvdata(&port->dev);
  }
  
  static inline void usb_set_serial_port_data(struct usb_serial_port *port,
  					    void *data)
  {
  	dev_set_drvdata(&port->dev, data);
  }
  
  /**
   * usb_serial - structure used by the usb-serial core for a device
   * @dev: pointer to the struct usb_device for this device
   * @type: pointer to the struct usb_serial_driver for this device
   * @interface: pointer to the struct usb_interface for this device
   * @num_ports: the number of ports this device has
   * @num_interrupt_in: number of interrupt in endpoints we have
   * @num_interrupt_out: number of interrupt out endpoints we have
   * @num_bulk_in: number of bulk in endpoints we have
   * @num_bulk_out: number of bulk out endpoints we have
   * @port: array of struct usb_serial_port structures for the different ports.
   * @private: place to put any driver specific information that is needed.  The
   *	usb-serial driver is required to manage this data, the usb-serial core
   *	will not touch this.  Use usb_get_serial_data() and
   *	usb_set_serial_data() to access this.
   */
  struct usb_serial {
  	struct usb_device		*dev;
  	struct usb_serial_driver	*type;
  	struct usb_interface		*interface;
  	unsigned char			disconnected:1;
  	unsigned char			suspending:1;
  	unsigned char			attached:1;
  	unsigned char			minors_reserved:1;
  	unsigned char			num_ports;
  	unsigned char			num_port_pointers;
  	char				num_interrupt_in;
  	char				num_interrupt_out;
  	char				num_bulk_in;
  	char				num_bulk_out;
  	struct usb_serial_port		*port[MAX_NUM_PORTS];
  	struct kref			kref;
  	struct mutex			disc_mutex;
  	void				*private;
  };
  #define to_usb_serial(d) container_of(d, struct usb_serial, kref)
  
  /* get and set the serial private data pointer helper functions */
  static inline void *usb_get_serial_data(struct usb_serial *serial)
  {
  	return serial->private;
  }
  
  static inline void usb_set_serial_data(struct usb_serial *serial, void *data)
  {
  	serial->private = data;
  }
  
  /**
   * usb_serial_driver - describes a usb serial driver
   * @description: pointer to a string that describes this driver.  This string
   *	used in the syslog messages when a device is inserted or removed.
   * @id_table: pointer to a list of usb_device_id structures that define all
   *	of the devices this structure can support.
   * @num_ports: the number of different ports this device will have.
   * @bulk_in_size: minimum number of bytes to allocate for bulk-in buffer
   *	(0 = end-point size)
   * @bulk_out_size: bytes to allocate for bulk-out buffer (0 = end-point size)
   * @calc_num_ports: pointer to a function to determine how many ports this
   *	device has dynamically.  It will be called after the probe()
   *	callback is called, but before attach()
   * @probe: pointer to the driver's probe function.
   *	This will be called when the device is inserted into the system,
   *	but before the device has been fully initialized by the usb_serial
   *	subsystem.  Use this function to download any firmware to the device,
   *	or any other early initialization that might be needed.
   *	Return 0 to continue on with the initialization sequence.  Anything
   *	else will abort it.
   * @attach: pointer to the driver's attach function.
   *	This will be called when the struct usb_serial structure is fully set
   *	set up.  Do any local initialization of the device, or any private
   *	memory structure allocation at this point in time.
   * @disconnect: pointer to the driver's disconnect function.  This will be
   *	called when the device is unplugged or unbound from the driver.
   * @release: pointer to the driver's release function.  This will be called
   *	when the usb_serial data structure is about to be destroyed.
   * @usb_driver: pointer to the struct usb_driver that controls this
   *	device.  This is necessary to allow dynamic ids to be added to
   *	the driver from sysfs.
   *
   * This structure is defines a USB Serial driver.  It provides all of
   * the information that the USB serial core code needs.  If the function
   * pointers are defined, then the USB serial core code will call them when
   * the corresponding tty port functions are called.  If they are not
   * called, the generic serial function will be used instead.
   *
   * The driver.owner field should be set to the module owner of this driver.
   * The driver.name field should be set to the name of this driver (remember
   * it will show up in sysfs, so it needs to be short and to the point.
   * Using the module name is a good idea.)
   */
  struct usb_serial_driver {
  	const char *description;
  	const struct usb_device_id *id_table;
  	char	num_ports;
  
  	struct list_head	driver_list;
  	struct device_driver	driver;
  	struct usb_driver	*usb_driver;
  	struct usb_dynids	dynids;
  
  	size_t			bulk_in_size;
  	size_t			bulk_out_size;
  
  	int (*probe)(struct usb_serial *serial, const struct usb_device_id *id);
  	int (*attach)(struct usb_serial *serial);
  	int (*calc_num_ports) (struct usb_serial *serial);
  
  	void (*disconnect)(struct usb_serial *serial);
  	void (*release)(struct usb_serial *serial);
  
  	int (*port_probe)(struct usb_serial_port *port);
  	int (*port_remove)(struct usb_serial_port *port);
  
  	int (*suspend)(struct usb_serial *serial, pm_message_t message);
  	int (*resume)(struct usb_serial *serial);
  	int (*reset_resume)(struct usb_serial *serial);
  
  	/* serial function calls */
  	/* Called by console and by the tty layer */
  	int  (*open)(struct tty_struct *tty, struct usb_serial_port *port);
  	void (*close)(struct usb_serial_port *port);
  	int  (*write)(struct tty_struct *tty, struct usb_serial_port *port,
  			const unsigned char *buf, int count);
  	/* Called only by the tty layer */
  	int  (*write_room)(struct tty_struct *tty);
  	int  (*ioctl)(struct tty_struct *tty,
  		      unsigned int cmd, unsigned long arg);
  	void (*set_termios)(struct tty_struct *tty,
  			struct usb_serial_port *port, struct ktermios *old);
  	void (*break_ctl)(struct tty_struct *tty, int break_state);
  	int  (*chars_in_buffer)(struct tty_struct *tty);
  	void (*wait_until_sent)(struct tty_struct *tty, long timeout);
  	bool (*tx_empty)(struct usb_serial_port *port);
  	void (*throttle)(struct tty_struct *tty);
  	void (*unthrottle)(struct tty_struct *tty);
  	int  (*tiocmget)(struct tty_struct *tty);
  	int  (*tiocmset)(struct tty_struct *tty,
  			 unsigned int set, unsigned int clear);
  	int  (*tiocmiwait)(struct tty_struct *tty, unsigned long arg);
  	int  (*get_icount)(struct tty_struct *tty,
  			struct serial_icounter_struct *icount);
  	/* Called by the tty layer for port level work. There may or may not
  	   be an attached tty at this point */
  	void (*dtr_rts)(struct usb_serial_port *port, int on);
  	int  (*carrier_raised)(struct usb_serial_port *port);
  	/* Called by the usb serial hooks to allow the user to rework the
  	   termios state */
  	void (*init_termios)(struct tty_struct *tty);
  	/* USB events */
  	void (*read_int_callback)(struct urb *urb);
  	void (*write_int_callback)(struct urb *urb);
  	void (*read_bulk_callback)(struct urb *urb);
  	void (*write_bulk_callback)(struct urb *urb);
  	/* Called by the generic read bulk callback */
  	void (*process_read_urb)(struct urb *urb);
  	/* Called by the generic write implementation */
  	int (*prepare_write_buffer)(struct usb_serial_port *port,
  						void *dest, size_t size);
  };
  #define to_usb_serial_driver(d) \
  	container_of(d, struct usb_serial_driver, driver)
  
  extern int usb_serial_register_drivers(struct usb_serial_driver *const serial_drivers[],
  		const char *name, const struct usb_device_id *id_table);
  extern void usb_serial_deregister_drivers(struct usb_serial_driver *const serial_drivers[]);
  extern void usb_serial_port_softint(struct usb_serial_port *port);
  
  extern int usb_serial_suspend(struct usb_interface *intf, pm_message_t message);
  extern int usb_serial_resume(struct usb_interface *intf);
  
  /* USB Serial console functions */
  #ifdef CONFIG_USB_SERIAL_CONSOLE
  extern void usb_serial_console_init(int minor);
  extern void usb_serial_console_exit(void);
  extern void usb_serial_console_disconnect(struct usb_serial *serial);
  #else
  static inline void usb_serial_console_init(int minor) { }
  static inline void usb_serial_console_exit(void) { }
  static inline void usb_serial_console_disconnect(struct usb_serial *serial) {}
  #endif
  
  /* Functions needed by other parts of the usbserial core */
  extern struct usb_serial_port *usb_serial_port_get_by_minor(unsigned int minor);
  extern void usb_serial_put(struct usb_serial *serial);
  extern int usb_serial_generic_open(struct tty_struct *tty,
  	struct usb_serial_port *port);
  extern int usb_serial_generic_write_start(struct usb_serial_port *port,
  							gfp_t mem_flags);
  extern int usb_serial_generic_write(struct tty_struct *tty,
  	struct usb_serial_port *port, const unsigned char *buf, int count);
  extern void usb_serial_generic_close(struct usb_serial_port *port);
  extern int usb_serial_generic_resume(struct usb_serial *serial);
  extern int usb_serial_generic_write_room(struct tty_struct *tty);
  extern int usb_serial_generic_chars_in_buffer(struct tty_struct *tty);
  extern void usb_serial_generic_wait_until_sent(struct tty_struct *tty,
  								long timeout);
  extern void usb_serial_generic_read_bulk_callback(struct urb *urb);
  extern void usb_serial_generic_write_bulk_callback(struct urb *urb);
  extern void usb_serial_generic_throttle(struct tty_struct *tty);
  extern void usb_serial_generic_unthrottle(struct tty_struct *tty);
  extern int usb_serial_generic_tiocmiwait(struct tty_struct *tty,
  							unsigned long arg);
  extern int usb_serial_generic_get_icount(struct tty_struct *tty,
  					struct serial_icounter_struct *icount);
  extern int usb_serial_generic_register(void);
  extern void usb_serial_generic_deregister(void);
  extern int usb_serial_generic_submit_read_urbs(struct usb_serial_port *port,
  						 gfp_t mem_flags);
  extern void usb_serial_generic_process_read_urb(struct urb *urb);
  extern int usb_serial_generic_prepare_write_buffer(struct usb_serial_port *port,
  						void *dest, size_t size);
  extern int usb_serial_handle_sysrq_char(struct usb_serial_port *port,
  					unsigned int ch);
  extern int usb_serial_handle_break(struct usb_serial_port *port);
  extern void usb_serial_handle_dcd_change(struct usb_serial_port *usb_port,
  					 struct tty_struct *tty,
  					 unsigned int status);
  
  
  extern int usb_serial_bus_register(struct usb_serial_driver *device);
  extern void usb_serial_bus_deregister(struct usb_serial_driver *device);
  
  extern struct usb_serial_driver usb_serial_generic_device;
  extern struct bus_type usb_serial_bus_type;
  extern struct tty_driver *usb_serial_tty_driver;
  
  static inline void usb_serial_debug_data(struct device *dev,
  					 const char *function, int size,
  					 const unsigned char *data)
  {
  	dev_dbg(dev, "%s - length = %d, data = %*ph
  ",
  		function, size, size, data);
  }
  
  /*
   * Macro for reporting errors in write path to avoid inifinite loop
   * when port is used as a console.
   */
  #define dev_err_console(usport, fmt, ...)				\
  do {									\
  	static bool __print_once;					\
  	struct usb_serial_port *__port = (usport);			\
  									\
  	if (!__port->port.console || !__print_once) {			\
  		__print_once = true;					\
  		dev_err(&__port->dev, fmt, ##__VA_ARGS__);		\
  	}								\
  } while (0)
  
  /*
   * module_usb_serial_driver() - Helper macro for registering a USB Serial driver
   * @__serial_drivers: list of usb_serial drivers to register
   * @__ids: all device ids that @__serial_drivers bind to
   *
   * Helper macro for USB serial drivers which do not do anything special
   * in module init/exit. This eliminates a lot of boilerplate. Each
   * module may only use this macro once, and calling it replaces
   * module_init() and module_exit()
   *
   */
  #define usb_serial_module_driver(__name, __serial_drivers, __ids)	\
  static int __init usb_serial_module_init(void)				\
  {									\
  	return usb_serial_register_drivers(__serial_drivers,		\
  					   __name, __ids);		\
  }									\
  module_init(usb_serial_module_init);					\
  static void __exit usb_serial_module_exit(void)				\
  {									\
  	usb_serial_deregister_drivers(__serial_drivers);		\
  }									\
  module_exit(usb_serial_module_exit);
  
  #define module_usb_serial_driver(__serial_drivers, __ids)		\
  	usb_serial_module_driver(KBUILD_MODNAME, __serial_drivers, __ids)
  
  #endif /* __LINUX_USB_SERIAL_H */