drivers/usb/gadget/function/u_serial.h

   1 /*
   2  * u_serial.h - interface to USB gadget "serial port"/TTY utilities
   3  *
   4  * Copyright (C) 2008 David Brownell
   5  * Copyright (C) 2008 by Nokia Corporation
   6  *
   7  * This software is distributed under the terms of the GNU General
   8  * Public License ("GPL") as published by the Free Software Foundation,
   9  * either version 2 of that License or (at your option) any later version.
  10  */
  11
  12 #ifndef __U_SERIAL_H
  13 #define __U_SERIAL_H
  14
  15 #include <linux/usb/composite.h>
  16 #include <linux/usb/cdc.h>
  17
  18 #define MAX_U_SERIAL_PORTS      4
  19
  20 struct f_serial_opts {
  21         struct usb_function_instance func_inst;
  22         u8 port_num;
  23 };
  24
  25 /*
  26  * One non-multiplexed "serial" I/O port ... there can be several of these
  27  * on any given USB peripheral device, if it provides enough endpoints.
  28  *
  29  * The "u_serial" utility component exists to do one thing:  manage TTY
  30  * style I/O using the USB peripheral endpoints listed here, including
  31  * hookups to sysfs and /dev for each logical "tty" device.
  32  *
  33  * REVISIT at least ACM could support tiocmget() if needed.
  34  *
  35  * REVISIT someday, allow multiplexing several TTYs over these endpoints.
  36  */
  37 struct gserial {
  38         struct usb_function             func;
  39
  40         /* port is managed by gserial_{connect,disconnect} */
  41         struct gs_port                  *ioport;
  42
  43         struct usb_ep                   *in;
  44         struct usb_ep                   *out;
  45
  46         /* REVISIT avoid this CDC-ACM support harder ... */
  47         struct usb_cdc_line_coding port_line_coding;    /* 9600-8-N-1 etc */
  48
  49         /* notification callbacks */
  50         void (*connect)(struct gserial *p);
  51         void (*disconnect)(struct gserial *p);
  52         int (*send_break)(struct gserial *p, int duration);
  53 };
  54
  55 /* utilities to allocate/free request and buffer */
  56 struct usb_request *gs_alloc_req(struct usb_ep *ep, unsigned len, gfp_t flags);
  57 void gs_free_req(struct usb_ep *, struct usb_request *req);
  58
  59 /* management of individual TTY ports */
  60 int gserial_alloc_line(unsigned char *port_line);
  61 void gserial_free_line(unsigned char port_line);
  62
  63 /* connect/disconnect is handled by individual functions */
  64 int gserial_connect(struct gserial *, u8 port_num);
  65 void gserial_disconnect(struct gserial *);
  66
  67 /* functions are bound to configurations by a config or gadget driver */
  68 int gser_bind_config(struct usb_configuration *c, u8 port_num);
  69 int obex_bind_config(struct usb_configuration *c, u8 port_num);
  70
  71 #endif /* __U_SERIAL_H */