| b.liu | e958203 | 2025-04-17 19:18:16 +0800 | [diff] [blame^] | 1 | // SPDX-License-Identifier: GPL-2.0+ |
| 2 | /* |
| 3 | * u_serial.h - interface to USB gadget "serial port"/TTY utilities |
| 4 | * |
| 5 | * Copyright (C) 2008 David Brownell |
| 6 | * Copyright (C) 2008 by Nokia Corporation |
| 7 | */ |
| 8 | |
| 9 | #ifndef __U_SERIAL_H |
| 10 | #define __U_SERIAL_H |
| 11 | |
| 12 | #include <linux/usb/composite.h> |
| 13 | #include <linux/usb/cdc.h> |
| 14 | |
| 15 | #define MAX_U_SERIAL_PORTS 4 |
| 16 | |
| 17 | struct f_serial_opts { |
| 18 | struct usb_function_instance func_inst; |
| 19 | u8 port_num; |
| 20 | }; |
| 21 | |
| 22 | /* |
| 23 | * One non-multiplexed "serial" I/O port ... there can be several of these |
| 24 | * on any given USB peripheral device, if it provides enough endpoints. |
| 25 | * |
| 26 | * The "u_serial" utility component exists to do one thing: manage TTY |
| 27 | * style I/O using the USB peripheral endpoints listed here, including |
| 28 | * hookups to sysfs and /dev for each logical "tty" device. |
| 29 | * |
| 30 | * REVISIT at least ACM could support tiocmget() if needed. |
| 31 | * |
| 32 | * REVISIT someday, allow multiplexing several TTYs over these endpoints. |
| 33 | */ |
| 34 | struct gserial { |
| 35 | struct usb_function func; |
| 36 | |
| 37 | /* port is managed by gserial_{connect,disconnect} */ |
| 38 | struct gs_port *ioport; |
| 39 | |
| 40 | struct usb_ep *in; |
| 41 | struct usb_ep *out; |
| 42 | |
| 43 | /* REVISIT avoid this CDC-ACM support harder ... */ |
| 44 | struct usb_cdc_line_coding port_line_coding; /* 9600-8-N-1 etc */ |
| 45 | |
| 46 | /* notification callbacks */ |
| 47 | void (*connect)(struct gserial *p); |
| 48 | void (*disconnect)(struct gserial *p); |
| 49 | int (*send_break)(struct gserial *p, int duration); |
| 50 | }; |
| 51 | |
| 52 | /* utilities to allocate/free request and buffer */ |
| 53 | struct usb_request *gs_alloc_req(struct usb_ep *ep, unsigned len, gfp_t flags); |
| 54 | void gs_free_req(struct usb_ep *, struct usb_request *req); |
| 55 | |
| 56 | /* management of individual TTY ports */ |
| 57 | int gserial_alloc_line(unsigned char *port_line); |
| 58 | void gserial_free_line(unsigned char port_line); |
| 59 | |
| 60 | /* connect/disconnect is handled by individual functions */ |
| 61 | int gserial_connect(struct gserial *, u8 port_num); |
| 62 | void gserial_disconnect(struct gserial *); |
| 63 | |
| 64 | /* functions are bound to configurations by a config or gadget driver */ |
| 65 | int gser_bind_config(struct usb_configuration *c, u8 port_num); |
| 66 | int obex_bind_config(struct usb_configuration *c, u8 port_num); |
| 67 | |
| 68 | #endif /* __U_SERIAL_H */ |