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
9 #ifndef __LINUX_USB_SERIAL_H
10 #define __LINUX_USB_SERIAL_H
11
12 #include <linux/kref.h>
13 #include <linux/mutex.h>
14 #include <linux/serial.h>
15 #include <linux/kfifo.h>
16 #include <linux/usb.h>
17
18 /* The maximum number of ports one device can grab at once */
19 #define MAX_NUM_PORTS 16
20
21 /* USB serial flags */
22 #define USB_SERIAL_WRITE_BUSY 0
23 #define USB_SERIAL_THROTTLED 1
24
25 /**
26 * usb_serial_port: structure for the specific ports of a device.
27 * @serial: pointer back to the struct usb_serial owner of this port.
28 * @port: pointer to the corresponding tty_port for this port.
29 * @lock: spinlock to grab when updating portions of this structure.
30 * @minor: the minor number of the port
31 * @port_number: the struct usb_serial port number of this port (starts at 0)
32 * @interrupt_in_buffer: pointer to the interrupt in buffer for this port.
33 * @interrupt_in_urb: pointer to the interrupt in struct urb for this port.
34 * @interrupt_in_endpointAddress: endpoint address for the interrupt in pipe
35 * for this port.
36 * @interrupt_out_buffer: pointer to the interrupt out buffer for this port.
37 * @interrupt_out_size: the size of the interrupt_out_buffer, in bytes.
38 * @interrupt_out_urb: pointer to the interrupt out struct urb for this port.
39 * @interrupt_out_endpointAddress: endpoint address for the interrupt out pipe
40 * for this port.
41 * @bulk_in_buffer: pointer to the bulk in buffer for this port.
42 * @bulk_in_size: the size of the bulk_in_buffer, in bytes.
43 * @read_urb: pointer to the bulk in struct urb for this port.
44 * @bulk_in_endpointAddress: endpoint address for the bulk in pipe for this
45 * port.
46 * @bulk_in_buffers: pointers to the bulk in buffers for this port
47 * @read_urbs: pointers to the bulk in urbs for this port
48 * @read_urbs_free: status bitmap the for bulk in urbs
49 * @bulk_out_buffer: pointer to the bulk out buffer for this port.
50 * @bulk_out_size: the size of the bulk_out_buffer, in bytes.
51 * @write_urb: pointer to the bulk out struct urb for this port.
52 * @write_fifo: kfifo used to buffer outgoing data
53 * @bulk_out_buffers: pointers to the bulk out buffers for this port
54 * @write_urbs: pointers to the bulk out urbs for this port
55 * @write_urbs_free: status bitmap the for bulk out urbs
56 * @icount: interrupt counters
57 * @tx_bytes: number of bytes currently in host stack queues
58 * @bulk_out_endpointAddress: endpoint address for the bulk out pipe for this
59 * port.
60 * @flags: usb serial port flags
61 * @work: work queue entry for the line discipline waking up.
62 * @dev: pointer to the serial device
63 *
64 * This structure is used by the usb-serial core and drivers for the specific
65 * ports of a device.
66 */
67 struct usb_serial_port {
68 struct usb_serial *serial;
69 struct tty_port port;
70 spinlock_t lock;
71 u32 minor;
72 u8 port_number;
73
74 unsigned char *interrupt_in_buffer;
75 struct urb *interrupt_in_urb;
76 __u8 interrupt_in_endpointAddress;
77
78 unsigned char *interrupt_out_buffer;
79 int interrupt_out_size;
80 struct urb *interrupt_out_urb;
81 __u8 interrupt_out_endpointAddress;
82
83 unsigned char *bulk_in_buffer;
84 int bulk_in_size;
85 struct urb *read_urb;
86 __u8 bulk_in_endpointAddress;
87
88 unsigned char *bulk_in_buffers[2];
89 struct urb *read_urbs[2];
90 unsigned long read_urbs_free;
91
92 unsigned char *bulk_out_buffer;
93 int bulk_out_size;
94 struct urb *write_urb;
95 struct kfifo write_fifo;
96
97 unsigned char *bulk_out_buffers[2];
98 struct urb *write_urbs[2];
99 unsigned long write_urbs_free;
100 __u8 bulk_out_endpointAddress;
101
102 struct async_icount icount;
103 int tx_bytes;
104
105 unsigned long flags;
106 struct work_struct work;
107 unsigned long sysrq; /* sysrq timeout */
108 struct device dev;
109 };
110 #define to_usb_serial_port(d) container_of(d, struct usb_serial_port, dev)
111
112 /* get and set the port private data pointer helper functions */
usb_get_serial_port_data(struct usb_serial_port * port)113 static inline void *usb_get_serial_port_data(struct usb_serial_port *port)
114 {
115 return dev_get_drvdata(&port->dev);
116 }
117
usb_set_serial_port_data(struct usb_serial_port * port,void * data)118 static inline void usb_set_serial_port_data(struct usb_serial_port *port,
119 void *data)
120 {
121 dev_set_drvdata(&port->dev, data);
122 }
123
124 /**
125 * usb_serial - structure used by the usb-serial core for a device
126 * @dev: pointer to the struct usb_device for this device
127 * @type: pointer to the struct usb_serial_driver for this device
128 * @interface: pointer to the struct usb_interface for this device
129 * @sibling: pointer to the struct usb_interface of any sibling interface
130 * @suspend_count: number of suspended (sibling) interfaces
131 * @num_ports: the number of ports this device has
132 * @num_interrupt_in: number of interrupt in endpoints we have
133 * @num_interrupt_out: number of interrupt out endpoints we have
134 * @num_bulk_in: number of bulk in endpoints we have
135 * @num_bulk_out: number of bulk out endpoints we have
136 * @port: array of struct usb_serial_port structures for the different ports.
137 * @private: place to put any driver specific information that is needed. The
138 * usb-serial driver is required to manage this data, the usb-serial core
139 * will not touch this. Use usb_get_serial_data() and
140 * usb_set_serial_data() to access this.
141 */
142 struct usb_serial {
143 struct usb_device *dev;
144 struct usb_serial_driver *type;
145 struct usb_interface *interface;
146 struct usb_interface *sibling;
147 unsigned int suspend_count;
148 unsigned char disconnected:1;
149 unsigned char attached:1;
150 unsigned char minors_reserved:1;
151 unsigned char num_ports;
152 unsigned char num_port_pointers;
153 unsigned char num_interrupt_in;
154 unsigned char num_interrupt_out;
155 unsigned char num_bulk_in;
156 unsigned char num_bulk_out;
157 struct usb_serial_port *port[MAX_NUM_PORTS];
158 struct kref kref;
159 struct mutex disc_mutex;
160 void *private;
161 };
162 #define to_usb_serial(d) container_of(d, struct usb_serial, kref)
163
164 /* get and set the serial private data pointer helper functions */
usb_get_serial_data(struct usb_serial * serial)165 static inline void *usb_get_serial_data(struct usb_serial *serial)
166 {
167 return serial->private;
168 }
169
usb_set_serial_data(struct usb_serial * serial,void * data)170 static inline void usb_set_serial_data(struct usb_serial *serial, void *data)
171 {
172 serial->private = data;
173 }
174
175 struct usb_serial_endpoints {
176 unsigned char num_bulk_in;
177 unsigned char num_bulk_out;
178 unsigned char num_interrupt_in;
179 unsigned char num_interrupt_out;
180 struct usb_endpoint_descriptor *bulk_in[MAX_NUM_PORTS];
181 struct usb_endpoint_descriptor *bulk_out[MAX_NUM_PORTS];
182 struct usb_endpoint_descriptor *interrupt_in[MAX_NUM_PORTS];
183 struct usb_endpoint_descriptor *interrupt_out[MAX_NUM_PORTS];
184 };
185
186 /**
187 * usb_serial_driver - describes a usb serial driver
188 * @description: pointer to a string that describes this driver. This string
189 * used in the syslog messages when a device is inserted or removed.
190 * @id_table: pointer to a list of usb_device_id structures that define all
191 * of the devices this structure can support.
192 * @num_ports: the number of different ports this device will have.
193 * @num_bulk_in: minimum number of bulk-in endpoints
194 * @num_bulk_out: minimum number of bulk-out endpoints
195 * @num_interrupt_in: minimum number of interrupt-in endpoints
196 * @num_interrupt_out: minimum number of interrupt-out endpoints
197 * @bulk_in_size: minimum number of bytes to allocate for bulk-in buffer
198 * (0 = end-point size)
199 * @bulk_out_size: bytes to allocate for bulk-out buffer (0 = end-point size)
200 * @calc_num_ports: pointer to a function to determine how many ports this
201 * device has dynamically. It can also be used to verify the number of
202 * endpoints or to modify the port-endpoint mapping. It will be called
203 * after the probe() callback is called, but before attach().
204 * @probe: pointer to the driver's probe function.
205 * This will be called when the device is inserted into the system,
206 * but before the device has been fully initialized by the usb_serial
207 * subsystem. Use this function to download any firmware to the device,
208 * or any other early initialization that might be needed.
209 * Return 0 to continue on with the initialization sequence. Anything
210 * else will abort it.
211 * @attach: pointer to the driver's attach function.
212 * This will be called when the struct usb_serial structure is fully
213 * set up. Do any local initialization of the device, or any private
214 * memory structure allocation at this point in time.
215 * @disconnect: pointer to the driver's disconnect function. This will be
216 * called when the device is unplugged or unbound from the driver.
217 * @release: pointer to the driver's release function. This will be called
218 * when the usb_serial data structure is about to be destroyed.
219 * @usb_driver: pointer to the struct usb_driver that controls this
220 * device. This is necessary to allow dynamic ids to be added to
221 * the driver from sysfs.
222 *
223 * This structure is defines a USB Serial driver. It provides all of
224 * the information that the USB serial core code needs. If the function
225 * pointers are defined, then the USB serial core code will call them when
226 * the corresponding tty port functions are called. If they are not
227 * called, the generic serial function will be used instead.
228 *
229 * The driver.owner field should be set to the module owner of this driver.
230 * The driver.name field should be set to the name of this driver (remember
231 * it will show up in sysfs, so it needs to be short and to the point.
232 * Using the module name is a good idea.)
233 */
234 struct usb_serial_driver {
235 const char *description;
236 const struct usb_device_id *id_table;
237
238 struct list_head driver_list;
239 struct device_driver driver;
240 struct usb_driver *usb_driver;
241 struct usb_dynids dynids;
242
243 unsigned char num_ports;
244
245 unsigned char num_bulk_in;
246 unsigned char num_bulk_out;
247 unsigned char num_interrupt_in;
248 unsigned char num_interrupt_out;
249
250 size_t bulk_in_size;
251 size_t bulk_out_size;
252
253 int (*probe)(struct usb_serial *serial, const struct usb_device_id *id);
254 int (*attach)(struct usb_serial *serial);
255 int (*calc_num_ports)(struct usb_serial *serial,
256 struct usb_serial_endpoints *epds);
257
258 void (*disconnect)(struct usb_serial *serial);
259 void (*release)(struct usb_serial *serial);
260
261 int (*port_probe)(struct usb_serial_port *port);
262 void (*port_remove)(struct usb_serial_port *port);
263
264 int (*suspend)(struct usb_serial *serial, pm_message_t message);
265 int (*resume)(struct usb_serial *serial);
266 int (*reset_resume)(struct usb_serial *serial);
267
268 /* serial function calls */
269 /* Called by console and by the tty layer */
270 int (*open)(struct tty_struct *tty, struct usb_serial_port *port);
271 void (*close)(struct usb_serial_port *port);
272 int (*write)(struct tty_struct *tty, struct usb_serial_port *port,
273 const unsigned char *buf, int count);
274 /* Called only by the tty layer */
275 unsigned int (*write_room)(struct tty_struct *tty);
276 int (*ioctl)(struct tty_struct *tty,
277 unsigned int cmd, unsigned long arg);
278 void (*get_serial)(struct tty_struct *tty, struct serial_struct *ss);
279 int (*set_serial)(struct tty_struct *tty, struct serial_struct *ss);
280 void (*set_termios)(struct tty_struct *tty, struct usb_serial_port *port,
281 const struct ktermios *old);
282 int (*break_ctl)(struct tty_struct *tty, int break_state);
283 unsigned int (*chars_in_buffer)(struct tty_struct *tty);
284 void (*wait_until_sent)(struct tty_struct *tty, long timeout);
285 bool (*tx_empty)(struct usb_serial_port *port);
286 void (*throttle)(struct tty_struct *tty);
287 void (*unthrottle)(struct tty_struct *tty);
288 int (*tiocmget)(struct tty_struct *tty);
289 int (*tiocmset)(struct tty_struct *tty,
290 unsigned int set, unsigned int clear);
291 int (*tiocmiwait)(struct tty_struct *tty, unsigned long arg);
292 int (*get_icount)(struct tty_struct *tty,
293 struct serial_icounter_struct *icount);
294 /* Called by the tty layer for port level work. There may or may not
295 be an attached tty at this point */
296 void (*dtr_rts)(struct usb_serial_port *port, int on);
297 int (*carrier_raised)(struct usb_serial_port *port);
298 /* Called by the usb serial hooks to allow the user to rework the
299 termios state */
300 void (*init_termios)(struct tty_struct *tty);
301 /* USB events */
302 void (*read_int_callback)(struct urb *urb);
303 void (*write_int_callback)(struct urb *urb);
304 void (*read_bulk_callback)(struct urb *urb);
305 void (*write_bulk_callback)(struct urb *urb);
306 /* Called by the generic read bulk callback */
307 void (*process_read_urb)(struct urb *urb);
308 /* Called by the generic write implementation */
309 int (*prepare_write_buffer)(struct usb_serial_port *port,
310 void *dest, size_t size);
311 };
312 #define to_usb_serial_driver(d) \
313 container_of(d, struct usb_serial_driver, driver)
314
315 #define usb_serial_register_drivers(serial_drivers, name, id_table) \
316 __usb_serial_register_drivers(serial_drivers, THIS_MODULE, name, id_table)
317 int __usb_serial_register_drivers(struct usb_serial_driver *const serial_drivers[],
318 struct module *owner, const char *name,
319 const struct usb_device_id *id_table);
320 void usb_serial_deregister_drivers(struct usb_serial_driver *const serial_drivers[]);
321 void usb_serial_port_softint(struct usb_serial_port *port);
322
323 int usb_serial_suspend(struct usb_interface *intf, pm_message_t message);
324 int usb_serial_resume(struct usb_interface *intf);
325
326 /* USB Serial console functions */
327 #ifdef CONFIG_USB_SERIAL_CONSOLE
328 void usb_serial_console_init(int minor);
329 void usb_serial_console_exit(void);
330 void usb_serial_console_disconnect(struct usb_serial *serial);
331 #else
usb_serial_console_init(int minor)332 static inline void usb_serial_console_init(int minor) { }
usb_serial_console_exit(void)333 static inline void usb_serial_console_exit(void) { }
usb_serial_console_disconnect(struct usb_serial * serial)334 static inline void usb_serial_console_disconnect(struct usb_serial *serial) {}
335 #endif
336
337 /* Functions needed by other parts of the usbserial core */
338 struct usb_serial_port *usb_serial_port_get_by_minor(unsigned int minor);
339 void usb_serial_put(struct usb_serial *serial);
340
341 int usb_serial_claim_interface(struct usb_serial *serial, struct usb_interface *intf);
342
343 int usb_serial_generic_open(struct tty_struct *tty, struct usb_serial_port *port);
344 int usb_serial_generic_write_start(struct usb_serial_port *port, gfp_t mem_flags);
345 int usb_serial_generic_write(struct tty_struct *tty, struct usb_serial_port *port,
346 const unsigned char *buf, int count);
347 void usb_serial_generic_close(struct usb_serial_port *port);
348 int usb_serial_generic_resume(struct usb_serial *serial);
349 unsigned int usb_serial_generic_write_room(struct tty_struct *tty);
350 unsigned int usb_serial_generic_chars_in_buffer(struct tty_struct *tty);
351 void usb_serial_generic_wait_until_sent(struct tty_struct *tty, long timeout);
352 void usb_serial_generic_read_bulk_callback(struct urb *urb);
353 void usb_serial_generic_write_bulk_callback(struct urb *urb);
354 void usb_serial_generic_throttle(struct tty_struct *tty);
355 void usb_serial_generic_unthrottle(struct tty_struct *tty);
356 int usb_serial_generic_tiocmiwait(struct tty_struct *tty, unsigned long arg);
357 int usb_serial_generic_get_icount(struct tty_struct *tty, struct serial_icounter_struct *icount);
358 int usb_serial_generic_register(void);
359 void usb_serial_generic_deregister(void);
360 int usb_serial_generic_submit_read_urbs(struct usb_serial_port *port, gfp_t mem_flags);
361 void usb_serial_generic_process_read_urb(struct urb *urb);
362 int usb_serial_generic_prepare_write_buffer(struct usb_serial_port *port, void *dest, size_t size);
363
364 #if defined(CONFIG_USB_SERIAL_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
365 int usb_serial_handle_sysrq_char(struct usb_serial_port *port, unsigned int ch);
366 int usb_serial_handle_break(struct usb_serial_port *port);
367 #else
usb_serial_handle_sysrq_char(struct usb_serial_port * port,unsigned int ch)368 static inline int usb_serial_handle_sysrq_char(struct usb_serial_port *port, unsigned int ch)
369 {
370 return 0;
371 }
usb_serial_handle_break(struct usb_serial_port * port)372 static inline int usb_serial_handle_break(struct usb_serial_port *port)
373 {
374 return 0;
375 }
376 #endif
377
378 void usb_serial_handle_dcd_change(struct usb_serial_port *usb_port,
379 struct tty_struct *tty, unsigned int status);
380
381
382 int usb_serial_bus_register(struct usb_serial_driver *device);
383 void usb_serial_bus_deregister(struct usb_serial_driver *device);
384
385 extern const struct bus_type usb_serial_bus_type;
386 extern struct tty_driver *usb_serial_tty_driver;
387
usb_serial_debug_data(struct device * dev,const char * function,int size,const unsigned char * data)388 static inline void usb_serial_debug_data(struct device *dev,
389 const char *function, int size,
390 const unsigned char *data)
391 {
392 dev_dbg(dev, "%s - length = %d, data = %*ph\n",
393 function, size, size, data);
394 }
395
396 /*
397 * Macro for reporting errors in write path to avoid infinite loop
398 * when port is used as a console.
399 */
400 #define dev_err_console(usport, fmt, ...) \
401 do { \
402 static bool __print_once; \
403 struct usb_serial_port *__port = (usport); \
404 \
405 if (!__port->port.console || !__print_once) { \
406 __print_once = true; \
407 dev_err(&__port->dev, fmt, ##__VA_ARGS__); \
408 } \
409 } while (0)
410
411 /*
412 * module_usb_serial_driver() - Helper macro for registering a USB Serial driver
413 * @__serial_drivers: list of usb_serial drivers to register
414 * @__ids: all device ids that @__serial_drivers bind to
415 *
416 * Helper macro for USB serial drivers which do not do anything special
417 * in module init/exit. This eliminates a lot of boilerplate. Each
418 * module may only use this macro once, and calling it replaces
419 * module_init() and module_exit()
420 *
421 */
422 #define usb_serial_module_driver(__name, __serial_drivers, __ids) \
423 static int __init usb_serial_module_init(void) \
424 { \
425 return usb_serial_register_drivers(__serial_drivers, \
426 __name, __ids); \
427 } \
428 module_init(usb_serial_module_init); \
429 static void __exit usb_serial_module_exit(void) \
430 { \
431 usb_serial_deregister_drivers(__serial_drivers); \
432 } \
433 module_exit(usb_serial_module_exit);
434
435 #define module_usb_serial_driver(__serial_drivers, __ids) \
436 usb_serial_module_driver(KBUILD_MODNAME, __serial_drivers, __ids)
437
438 #endif /* __LINUX_USB_SERIAL_H */
439
440