1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * USB Serial Converter stuff
4 *
5 * Copyright (C) 1999 - 2012
6 * Greg Kroah-Hartman (greg@kroah.com)
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; version 2 of the License.
11 *
12 */
13
14 #ifndef __LINUX_USB_SERIAL_H
15 #define __LINUX_USB_SERIAL_H
16
17 #include <linux/kref.h>
18 #include <linux/mutex.h>
19 #include <linux/serial.h>
20 #include <linux/sysrq.h>
21 #include <linux/kfifo.h>
22
23 /* The maximum number of ports one device can grab at once */
24 #define MAX_NUM_PORTS 16
25
26 /* USB serial flags */
27 #define USB_SERIAL_WRITE_BUSY 0
28 #define USB_SERIAL_THROTTLED 1
29
30 /**
31 * usb_serial_port: structure for the specific ports of a device.
32 * @serial: pointer back to the struct usb_serial owner of this port.
33 * @port: pointer to the corresponding tty_port for this port.
34 * @lock: spinlock to grab when updating portions of this structure.
35 * @minor: the minor number of the port
36 * @port_number: the struct usb_serial port number of this port (starts at 0)
37 * @interrupt_in_buffer: pointer to the interrupt in buffer for this port.
38 * @interrupt_in_urb: pointer to the interrupt in struct urb for this port.
39 * @interrupt_in_endpointAddress: endpoint address for the interrupt in pipe
40 * for this port.
41 * @interrupt_out_buffer: pointer to the interrupt out buffer for this port.
42 * @interrupt_out_size: the size of the interrupt_out_buffer, in bytes.
43 * @interrupt_out_urb: pointer to the interrupt out struct urb for this port.
44 * @interrupt_out_endpointAddress: endpoint address for the interrupt out pipe
45 * for this port.
46 * @bulk_in_buffer: pointer to the bulk in buffer for this port.
47 * @bulk_in_size: the size of the bulk_in_buffer, in bytes.
48 * @read_urb: pointer to the bulk in struct urb for this port.
49 * @bulk_in_endpointAddress: endpoint address for the bulk in pipe for this
50 * port.
51 * @bulk_in_buffers: pointers to the bulk in buffers for this port
52 * @read_urbs: pointers to the bulk in urbs for this port
53 * @read_urbs_free: status bitmap the for bulk in urbs
54 * @bulk_out_buffer: pointer to the bulk out buffer for this port.
55 * @bulk_out_size: the size of the bulk_out_buffer, in bytes.
56 * @write_urb: pointer to the bulk out struct urb for this port.
57 * @write_fifo: kfifo used to buffer outgoing data
58 * @bulk_out_buffers: pointers to the bulk out buffers for this port
59 * @write_urbs: pointers to the bulk out urbs for this port
60 * @write_urbs_free: status bitmap the for bulk out urbs
61 * @icount: interrupt counters
62 * @tx_bytes: number of bytes currently in host stack queues
63 * @bulk_out_endpointAddress: endpoint address for the bulk out pipe for this
64 * port.
65 * @flags: usb serial port flags
66 * @write_wait: a wait_queue_head_t used by the port.
67 * @work: work queue entry for the line discipline waking up.
68 * @dev: pointer to the serial device
69 *
70 * This structure is used by the usb-serial core and drivers for the specific
71 * ports of a device.
72 */
73 struct usb_serial_port {
74 struct usb_serial *serial;
75 struct tty_port port;
76 spinlock_t lock;
77 u32 minor;
78 u8 port_number;
79
80 unsigned char *interrupt_in_buffer;
81 struct urb *interrupt_in_urb;
82 __u8 interrupt_in_endpointAddress;
83
84 unsigned char *interrupt_out_buffer;
85 int interrupt_out_size;
86 struct urb *interrupt_out_urb;
87 __u8 interrupt_out_endpointAddress;
88
89 unsigned char *bulk_in_buffer;
90 int bulk_in_size;
91 struct urb *read_urb;
92 __u8 bulk_in_endpointAddress;
93
94 unsigned char *bulk_in_buffers[2];
95 struct urb *read_urbs[2];
96 unsigned long read_urbs_free;
97
98 unsigned char *bulk_out_buffer;
99 int bulk_out_size;
100 struct urb *write_urb;
101 struct kfifo write_fifo;
102
103 unsigned char *bulk_out_buffers[2];
104 struct urb *write_urbs[2];
105 unsigned long write_urbs_free;
106 __u8 bulk_out_endpointAddress;
107
108 struct async_icount icount;
109 int tx_bytes;
110
111 unsigned long flags;
112 wait_queue_head_t write_wait;
113 struct work_struct work;
114 unsigned long sysrq; /* sysrq timeout */
115 struct device dev;
116 };
117 #define to_usb_serial_port(d) container_of(d, struct usb_serial_port, dev)
118
119 /* get and set the port private data pointer helper functions */
120 static inline void *usb_get_serial_port_data(struct usb_serial_port *port)
121 {
122 return dev_get_drvdata(&port->dev);
123 }
124
125 static inline void usb_set_serial_port_data(struct usb_serial_port *port,
126 void *data)
127 {
128 dev_set_drvdata(&port->dev, data);
129 }
130
131 /**
132 * usb_serial - structure used by the usb-serial core for a device
133 * @dev: pointer to the struct usb_device for this device
134 * @type: pointer to the struct usb_serial_driver for this device
135 * @interface: pointer to the struct usb_interface for this device
136 * @num_ports: the number of ports this device has
137 * @num_interrupt_in: number of interrupt in endpoints we have
138 * @num_interrupt_out: number of interrupt out endpoints we have
139 * @num_bulk_in: number of bulk in endpoints we have
140 * @num_bulk_out: number of bulk out endpoints we have
141 * @port: array of struct usb_serial_port structures for the different ports.
142 * @private: place to put any driver specific information that is needed. The
143 * usb-serial driver is required to manage this data, the usb-serial core
144 * will not touch this. Use usb_get_serial_data() and
145 * usb_set_serial_data() to access this.
146 */
147 struct usb_serial {
148 struct usb_device *dev;
149 struct usb_serial_driver *type;
150 struct usb_interface *interface;
151 unsigned char disconnected:1;
152 unsigned char suspending:1;
153 unsigned char attached:1;
154 unsigned char minors_reserved:1;
155 unsigned char num_ports;
156 unsigned char num_port_pointers;
157 unsigned char num_interrupt_in;
158 unsigned char num_interrupt_out;
159 unsigned char num_bulk_in;
160 unsigned char num_bulk_out;
161 struct usb_serial_port *port[MAX_NUM_PORTS];
162 struct kref kref;
163 struct mutex disc_mutex;
164 void *private;
165 };
166 #define to_usb_serial(d) container_of(d, struct usb_serial, kref)
167
168 /* get and set the serial private data pointer helper functions */
169 static inline void *usb_get_serial_data(struct usb_serial *serial)
170 {
171 return serial->private;
172 }
173
174 static inline void usb_set_serial_data(struct usb_serial *serial, void *data)
175 {
176 serial->private = data;
177 }
178
179 struct usb_serial_endpoints {
180 unsigned char num_bulk_in;
181 unsigned char num_bulk_out;
182 unsigned char num_interrupt_in;
183 unsigned char num_interrupt_out;
184 struct usb_endpoint_descriptor *bulk_in[MAX_NUM_PORTS];
185 struct usb_endpoint_descriptor *bulk_out[MAX_NUM_PORTS];
186 struct usb_endpoint_descriptor *interrupt_in[MAX_NUM_PORTS];
187 struct usb_endpoint_descriptor *interrupt_out[MAX_NUM_PORTS];
188 };
189
190 /**
191 * usb_serial_driver - describes a usb serial driver
192 * @description: pointer to a string that describes this driver. This string
193 * used in the syslog messages when a device is inserted or removed.
194 * @id_table: pointer to a list of usb_device_id structures that define all
195 * of the devices this structure can support.
196 * @num_ports: the number of different ports this device will have.
197 * @num_bulk_in: minimum number of bulk-in endpoints
198 * @num_bulk_out: minimum number of bulk-out endpoints
199 * @num_interrupt_in: minimum number of interrupt-in endpoints
200 * @num_interrupt_out: minimum number of interrupt-out endpoints
201 * @bulk_in_size: minimum number of bytes to allocate for bulk-in buffer
202 * (0 = end-point size)
203 * @bulk_out_size: bytes to allocate for bulk-out buffer (0 = end-point size)
204 * @calc_num_ports: pointer to a function to determine how many ports this
205 * device has dynamically. It can also be used to verify the number of
206 * endpoints or to modify the port-endpoint mapping. It will be called
207 * after the probe() callback is called, but before attach().
208 * @probe: pointer to the driver's probe function.
209 * This will be called when the device is inserted into the system,
210 * but before the device has been fully initialized by the usb_serial
211 * subsystem. Use this function to download any firmware to the device,
212 * or any other early initialization that might be needed.
213 * Return 0 to continue on with the initialization sequence. Anything
214 * else will abort it.
215 * @attach: pointer to the driver's attach function.
216 * This will be called when the struct usb_serial structure is fully set
217 * set up. Do any local initialization of the device, or any private
218 * memory structure allocation at this point in time.
219 * @disconnect: pointer to the driver's disconnect function. This will be
220 * called when the device is unplugged or unbound from the driver.
221 * @release: pointer to the driver's release function. This will be called
222 * when the usb_serial data structure is about to be destroyed.
223 * @usb_driver: pointer to the struct usb_driver that controls this
224 * device. This is necessary to allow dynamic ids to be added to
225 * the driver from sysfs.
226 *
227 * This structure is defines a USB Serial driver. It provides all of
228 * the information that the USB serial core code needs. If the function
229 * pointers are defined, then the USB serial core code will call them when
230 * the corresponding tty port functions are called. If they are not
231 * called, the generic serial function will be used instead.
232 *
233 * The driver.owner field should be set to the module owner of this driver.
234 * The driver.name field should be set to the name of this driver (remember
235 * it will show up in sysfs, so it needs to be short and to the point.
236 * Using the module name is a good idea.)
237 */
238 struct usb_serial_driver {
239 const char *description;
240 const struct usb_device_id *id_table;
241
242 struct list_head driver_list;
243 struct device_driver driver;
244 struct usb_driver *usb_driver;
245 struct usb_dynids dynids;
246
247 unsigned char num_ports;
248
249 unsigned char num_bulk_in;
250 unsigned char num_bulk_out;
251 unsigned char num_interrupt_in;
252 unsigned char num_interrupt_out;
253
254 size_t bulk_in_size;
255 size_t bulk_out_size;
256
257 int (*probe)(struct usb_serial *serial, const struct usb_device_id *id);
258 int (*attach)(struct usb_serial *serial);
259 int (*calc_num_ports)(struct usb_serial *serial,
260 struct usb_serial_endpoints *epds);
261
262 void (*disconnect)(struct usb_serial *serial);
263 void (*release)(struct usb_serial *serial);
264
265 int (*port_probe)(struct usb_serial_port *port);
266 int (*port_remove)(struct usb_serial_port *port);
267
268 int (*suspend)(struct usb_serial *serial, pm_message_t message);
269 int (*resume)(struct usb_serial *serial);
270 int (*reset_resume)(struct usb_serial *serial);
271
272 /* serial function calls */
273 /* Called by console and by the tty layer */
274 int (*open)(struct tty_struct *tty, struct usb_serial_port *port);
275 void (*close)(struct usb_serial_port *port);
276 int (*write)(struct tty_struct *tty, struct usb_serial_port *port,
277 const unsigned char *buf, int count);
278 /* Called only by the tty layer */
279 int (*write_room)(struct tty_struct *tty);
280 int (*ioctl)(struct tty_struct *tty,
281 unsigned int cmd, unsigned long arg);
282 int (*get_serial)(struct tty_struct *tty, struct serial_struct *ss);
283 int (*set_serial)(struct tty_struct *tty, struct serial_struct *ss);
284 void (*set_termios)(struct tty_struct *tty,
285 struct usb_serial_port *port, struct ktermios *old);
286 void (*break_ctl)(struct tty_struct *tty, int break_state);
287 int (*chars_in_buffer)(struct tty_struct *tty);
288 void (*wait_until_sent)(struct tty_struct *tty, long timeout);
289 bool (*tx_empty)(struct usb_serial_port *port);
290 void (*throttle)(struct tty_struct *tty);
291 void (*unthrottle)(struct tty_struct *tty);
292 int (*tiocmget)(struct tty_struct *tty);
293 int (*tiocmset)(struct tty_struct *tty,
294 unsigned int set, unsigned int clear);
295 int (*tiocmiwait)(struct tty_struct *tty, unsigned long arg);
296 int (*get_icount)(struct tty_struct *tty,
297 struct serial_icounter_struct *icount);
298 /* Called by the tty layer for port level work. There may or may not
299 be an attached tty at this point */
300 void (*dtr_rts)(struct usb_serial_port *port, int on);
301 int (*carrier_raised)(struct usb_serial_port *port);
302 /* Called by the usb serial hooks to allow the user to rework the
303 termios state */
304 void (*init_termios)(struct tty_struct *tty);
305 /* USB events */
306 void (*read_int_callback)(struct urb *urb);
307 void (*write_int_callback)(struct urb *urb);
308 void (*read_bulk_callback)(struct urb *urb);
309 void (*write_bulk_callback)(struct urb *urb);
310 /* Called by the generic read bulk callback */
311 void (*process_read_urb)(struct urb *urb);
312 /* Called by the generic write implementation */
313 int (*prepare_write_buffer)(struct usb_serial_port *port,
314 void *dest, size_t size);
315 };
316 #define to_usb_serial_driver(d) \
317 container_of(d, struct usb_serial_driver, driver)
318
319 extern int usb_serial_register_drivers(struct usb_serial_driver *const serial_drivers[],
320 const char *name, const struct usb_device_id *id_table);
321 extern void usb_serial_deregister_drivers(struct usb_serial_driver *const serial_drivers[]);
322 extern void usb_serial_port_softint(struct usb_serial_port *port);
323
324 extern int usb_serial_suspend(struct usb_interface *intf, pm_message_t message);
325 extern int usb_serial_resume(struct usb_interface *intf);
326
327 /* USB Serial console functions */
328 #ifdef CONFIG_USB_SERIAL_CONSOLE
329 extern void usb_serial_console_init(int minor);
330 extern void usb_serial_console_exit(void);
331 extern void usb_serial_console_disconnect(struct usb_serial *serial);
332 #else
333 static inline void usb_serial_console_init(int minor) { }
334 static inline void usb_serial_console_exit(void) { }
335 static inline void usb_serial_console_disconnect(struct usb_serial *serial) {}
336 #endif
337
338 /* Functions needed by other parts of the usbserial core */
339 extern struct usb_serial_port *usb_serial_port_get_by_minor(unsigned int minor);
340 extern void usb_serial_put(struct usb_serial *serial);
341 extern int usb_serial_generic_open(struct tty_struct *tty,
342 struct usb_serial_port *port);
343 extern int usb_serial_generic_write_start(struct usb_serial_port *port,
344 gfp_t mem_flags);
345 extern int usb_serial_generic_write(struct tty_struct *tty,
346 struct usb_serial_port *port, const unsigned char *buf, int count);
347 extern void usb_serial_generic_close(struct usb_serial_port *port);
348 extern int usb_serial_generic_resume(struct usb_serial *serial);
349 extern int usb_serial_generic_write_room(struct tty_struct *tty);
350 extern int usb_serial_generic_chars_in_buffer(struct tty_struct *tty);
351 extern void usb_serial_generic_wait_until_sent(struct tty_struct *tty,
352 long timeout);
353 extern void usb_serial_generic_read_bulk_callback(struct urb *urb);
354 extern void usb_serial_generic_write_bulk_callback(struct urb *urb);
355 extern void usb_serial_generic_throttle(struct tty_struct *tty);
356 extern void usb_serial_generic_unthrottle(struct tty_struct *tty);
357 extern int usb_serial_generic_tiocmiwait(struct tty_struct *tty,
358 unsigned long arg);
359 extern int usb_serial_generic_get_icount(struct tty_struct *tty,
360 struct serial_icounter_struct *icount);
361 extern int usb_serial_generic_register(void);
362 extern void usb_serial_generic_deregister(void);
363 extern int usb_serial_generic_submit_read_urbs(struct usb_serial_port *port,
364 gfp_t mem_flags);
365 extern void usb_serial_generic_process_read_urb(struct urb *urb);
366 extern int usb_serial_generic_prepare_write_buffer(struct usb_serial_port *port,
367 void *dest, size_t size);
368 extern int usb_serial_handle_sysrq_char(struct usb_serial_port *port,
369 unsigned int ch);
370 extern int usb_serial_handle_break(struct usb_serial_port *port);
371 extern void usb_serial_handle_dcd_change(struct usb_serial_port *usb_port,
372 struct tty_struct *tty,
373 unsigned int status);
374
375
376 extern int usb_serial_bus_register(struct usb_serial_driver *device);
377 extern void usb_serial_bus_deregister(struct usb_serial_driver *device);
378
379 extern struct bus_type usb_serial_bus_type;
380 extern struct tty_driver *usb_serial_tty_driver;
381
382 static inline void usb_serial_debug_data(struct device *dev,
383 const char *function, int size,
384 const unsigned char *data)
385 {
386 dev_dbg(dev, "%s - length = %d, data = %*ph\n",
387 function, size, size, data);
388 }
389
390 /*
391 * Macro for reporting errors in write path to avoid inifinite loop
392 * when port is used as a console.
393 */
394 #define dev_err_console(usport, fmt, ...) \
395 do { \
396 static bool __print_once; \
397 struct usb_serial_port *__port = (usport); \
398 \
399 if (!__port->port.console || !__print_once) { \
400 __print_once = true; \
401 dev_err(&__port->dev, fmt, ##__VA_ARGS__); \
402 } \
403 } while (0)
404
405 /*
406 * module_usb_serial_driver() - Helper macro for registering a USB Serial driver
407 * @__serial_drivers: list of usb_serial drivers to register
408 * @__ids: all device ids that @__serial_drivers bind to
409 *
410 * Helper macro for USB serial drivers which do not do anything special
411 * in module init/exit. This eliminates a lot of boilerplate. Each
412 * module may only use this macro once, and calling it replaces
413 * module_init() and module_exit()
414 *
415 */
416 #define usb_serial_module_driver(__name, __serial_drivers, __ids) \
417 static int __init usb_serial_module_init(void) \
418 { \
419 return usb_serial_register_drivers(__serial_drivers, \
420 __name, __ids); \
421 } \
422 module_init(usb_serial_module_init); \
423 static void __exit usb_serial_module_exit(void) \
424 { \
425 usb_serial_deregister_drivers(__serial_drivers); \
426 } \
427 module_exit(usb_serial_module_exit);
428
429 #define module_usb_serial_driver(__serial_drivers, __ids) \
430 usb_serial_module_driver(KBUILD_MODNAME, __serial_drivers, __ids)
431
432 #endif /* __LINUX_USB_SERIAL_H */
433