xref: /linux/include/linux/usb/serial.h (revision e58e871becec2d3b04ed91c0c16fe8deac9c9dfa)
1 /*
2  * USB Serial Converter stuff
3  *
4  *	Copyright (C) 1999 - 2012
5  *	    Greg Kroah-Hartman (greg@kroah.com)
6  *
7  *	This program is free software; you can redistribute it and/or modify
8  *	it under the terms of the GNU General Public License as published by
9  *	the Free Software Foundation; version 2 of the License.
10  *
11  */
12 
13 #ifndef __LINUX_USB_SERIAL_H
14 #define __LINUX_USB_SERIAL_H
15 
16 #include <linux/kref.h>
17 #include <linux/mutex.h>
18 #include <linux/serial.h>
19 #include <linux/sysrq.h>
20 #include <linux/kfifo.h>
21 
22 /* The maximum number of ports one device can grab at once */
23 #define MAX_NUM_PORTS		16
24 
25 /* parity check flag */
26 #define RELEVANT_IFLAG(iflag)	(iflag & (IGNBRK|BRKINT|IGNPAR|PARMRK|INPCK))
27 
28 /* USB serial flags */
29 #define USB_SERIAL_WRITE_BUSY	0
30 
31 /**
32  * usb_serial_port: structure for the specific ports of a device.
33  * @serial: pointer back to the struct usb_serial owner of this port.
34  * @port: pointer to the corresponding tty_port for this port.
35  * @lock: spinlock to grab when updating portions of this structure.
36  * @minor: the minor number of the port
37  * @port_number: the struct usb_serial port number of this port (starts at 0)
38  * @interrupt_in_buffer: pointer to the interrupt in buffer for this port.
39  * @interrupt_in_urb: pointer to the interrupt in struct urb for this port.
40  * @interrupt_in_endpointAddress: endpoint address for the interrupt in pipe
41  *	for this port.
42  * @interrupt_out_buffer: pointer to the interrupt out buffer for this port.
43  * @interrupt_out_size: the size of the interrupt_out_buffer, in bytes.
44  * @interrupt_out_urb: pointer to the interrupt out struct urb for this port.
45  * @interrupt_out_endpointAddress: endpoint address for the interrupt out pipe
46  *	for this port.
47  * @bulk_in_buffer: pointer to the bulk in buffer for this port.
48  * @bulk_in_size: the size of the bulk_in_buffer, in bytes.
49  * @read_urb: pointer to the bulk in struct urb for this port.
50  * @bulk_in_endpointAddress: endpoint address for the bulk in pipe for this
51  *	port.
52  * @bulk_in_buffers: pointers to the bulk in buffers for this port
53  * @read_urbs: pointers to the bulk in urbs for this port
54  * @read_urbs_free: status bitmap the for bulk in urbs
55  * @bulk_out_buffer: pointer to the bulk out buffer for this port.
56  * @bulk_out_size: the size of the bulk_out_buffer, in bytes.
57  * @write_urb: pointer to the bulk out struct urb for this port.
58  * @write_fifo: kfifo used to buffer outgoing data
59  * @bulk_out_buffers: pointers to the bulk out buffers for this port
60  * @write_urbs: pointers to the bulk out urbs for this port
61  * @write_urbs_free: status bitmap the for bulk out urbs
62  * @icount: interrupt counters
63  * @tx_bytes: number of bytes currently in host stack queues
64  * @bulk_out_endpointAddress: endpoint address for the bulk out pipe for this
65  *	port.
66  * @flags: usb serial port flags
67  * @write_wait: a wait_queue_head_t used by the port.
68  * @work: work queue entry for the line discipline waking up.
69  * @throttled: nonzero if the read urb is inactive to throttle the device
70  * @throttle_req: nonzero if the tty wants to throttle us
71  * @dev: pointer to the serial device
72  *
73  * This structure is used by the usb-serial core and drivers for the specific
74  * ports of a device.
75  */
76 struct usb_serial_port {
77 	struct usb_serial	*serial;
78 	struct tty_port		port;
79 	spinlock_t		lock;
80 	u32			minor;
81 	u8			port_number;
82 
83 	unsigned char		*interrupt_in_buffer;
84 	struct urb		*interrupt_in_urb;
85 	__u8			interrupt_in_endpointAddress;
86 
87 	unsigned char		*interrupt_out_buffer;
88 	int			interrupt_out_size;
89 	struct urb		*interrupt_out_urb;
90 	__u8			interrupt_out_endpointAddress;
91 
92 	unsigned char		*bulk_in_buffer;
93 	int			bulk_in_size;
94 	struct urb		*read_urb;
95 	__u8			bulk_in_endpointAddress;
96 
97 	unsigned char		*bulk_in_buffers[2];
98 	struct urb		*read_urbs[2];
99 	unsigned long		read_urbs_free;
100 
101 	unsigned char		*bulk_out_buffer;
102 	int			bulk_out_size;
103 	struct urb		*write_urb;
104 	struct kfifo		write_fifo;
105 
106 	unsigned char		*bulk_out_buffers[2];
107 	struct urb		*write_urbs[2];
108 	unsigned long		write_urbs_free;
109 	__u8			bulk_out_endpointAddress;
110 
111 	struct async_icount	icount;
112 	int			tx_bytes;
113 
114 	unsigned long		flags;
115 	wait_queue_head_t	write_wait;
116 	struct work_struct	work;
117 	char			throttled;
118 	char			throttle_req;
119 	unsigned long		sysrq; /* sysrq timeout */
120 	struct device		dev;
121 };
122 #define to_usb_serial_port(d) container_of(d, struct usb_serial_port, dev)
123 
124 /* get and set the port private data pointer helper functions */
125 static inline void *usb_get_serial_port_data(struct usb_serial_port *port)
126 {
127 	return dev_get_drvdata(&port->dev);
128 }
129 
130 static inline void usb_set_serial_port_data(struct usb_serial_port *port,
131 					    void *data)
132 {
133 	dev_set_drvdata(&port->dev, data);
134 }
135 
136 /**
137  * usb_serial - structure used by the usb-serial core for a device
138  * @dev: pointer to the struct usb_device for this device
139  * @type: pointer to the struct usb_serial_driver for this device
140  * @interface: pointer to the struct usb_interface for this device
141  * @num_ports: the number of ports this device has
142  * @num_interrupt_in: number of interrupt in endpoints we have
143  * @num_interrupt_out: number of interrupt out endpoints we have
144  * @num_bulk_in: number of bulk in endpoints we have
145  * @num_bulk_out: number of bulk out endpoints we have
146  * @port: array of struct usb_serial_port structures for the different ports.
147  * @private: place to put any driver specific information that is needed.  The
148  *	usb-serial driver is required to manage this data, the usb-serial core
149  *	will not touch this.  Use usb_get_serial_data() and
150  *	usb_set_serial_data() to access this.
151  */
152 struct usb_serial {
153 	struct usb_device		*dev;
154 	struct usb_serial_driver	*type;
155 	struct usb_interface		*interface;
156 	unsigned char			disconnected:1;
157 	unsigned char			suspending:1;
158 	unsigned char			attached:1;
159 	unsigned char			minors_reserved:1;
160 	unsigned char			num_ports;
161 	unsigned char			num_port_pointers;
162 	unsigned char			num_interrupt_in;
163 	unsigned char			num_interrupt_out;
164 	unsigned char			num_bulk_in;
165 	unsigned char			num_bulk_out;
166 	struct usb_serial_port		*port[MAX_NUM_PORTS];
167 	struct kref			kref;
168 	struct mutex			disc_mutex;
169 	void				*private;
170 };
171 #define to_usb_serial(d) container_of(d, struct usb_serial, kref)
172 
173 /* get and set the serial private data pointer helper functions */
174 static inline void *usb_get_serial_data(struct usb_serial *serial)
175 {
176 	return serial->private;
177 }
178 
179 static inline void usb_set_serial_data(struct usb_serial *serial, void *data)
180 {
181 	serial->private = data;
182 }
183 
184 struct usb_serial_endpoints {
185 	unsigned char num_bulk_in;
186 	unsigned char num_bulk_out;
187 	unsigned char num_interrupt_in;
188 	unsigned char num_interrupt_out;
189 	struct usb_endpoint_descriptor *bulk_in[MAX_NUM_PORTS];
190 	struct usb_endpoint_descriptor *bulk_out[MAX_NUM_PORTS];
191 	struct usb_endpoint_descriptor *interrupt_in[MAX_NUM_PORTS];
192 	struct usb_endpoint_descriptor *interrupt_out[MAX_NUM_PORTS];
193 };
194 
195 /**
196  * usb_serial_driver - describes a usb serial driver
197  * @description: pointer to a string that describes this driver.  This string
198  *	used in the syslog messages when a device is inserted or removed.
199  * @id_table: pointer to a list of usb_device_id structures that define all
200  *	of the devices this structure can support.
201  * @num_ports: the number of different ports this device will have.
202  * @num_bulk_in: minimum number of bulk-in endpoints
203  * @num_bulk_out: minimum number of bulk-out endpoints
204  * @num_interrupt_in: minimum number of interrupt-in endpoints
205  * @num_interrupt_out: minimum number of interrupt-out endpoints
206  * @bulk_in_size: minimum number of bytes to allocate for bulk-in buffer
207  *	(0 = end-point size)
208  * @bulk_out_size: bytes to allocate for bulk-out buffer (0 = end-point size)
209  * @calc_num_ports: pointer to a function to determine how many ports this
210  *	device has dynamically. It can also be used to verify the number of
211  *	endpoints or to modify the port-endpoint mapping. It will be called
212  *	after the probe() callback is called, but before attach().
213  * @probe: pointer to the driver's probe function.
214  *	This will be called when the device is inserted into the system,
215  *	but before the device has been fully initialized by the usb_serial
216  *	subsystem.  Use this function to download any firmware to the device,
217  *	or any other early initialization that might be needed.
218  *	Return 0 to continue on with the initialization sequence.  Anything
219  *	else will abort it.
220  * @attach: pointer to the driver's attach function.
221  *	This will be called when the struct usb_serial structure is fully set
222  *	set up.  Do any local initialization of the device, or any private
223  *	memory structure allocation at this point in time.
224  * @disconnect: pointer to the driver's disconnect function.  This will be
225  *	called when the device is unplugged or unbound from the driver.
226  * @release: pointer to the driver's release function.  This will be called
227  *	when the usb_serial data structure is about to be destroyed.
228  * @usb_driver: pointer to the struct usb_driver that controls this
229  *	device.  This is necessary to allow dynamic ids to be added to
230  *	the driver from sysfs.
231  *
232  * This structure is defines a USB Serial driver.  It provides all of
233  * the information that the USB serial core code needs.  If the function
234  * pointers are defined, then the USB serial core code will call them when
235  * the corresponding tty port functions are called.  If they are not
236  * called, the generic serial function will be used instead.
237  *
238  * The driver.owner field should be set to the module owner of this driver.
239  * The driver.name field should be set to the name of this driver (remember
240  * it will show up in sysfs, so it needs to be short and to the point.
241  * Using the module name is a good idea.)
242  */
243 struct usb_serial_driver {
244 	const char *description;
245 	const struct usb_device_id *id_table;
246 
247 	struct list_head	driver_list;
248 	struct device_driver	driver;
249 	struct usb_driver	*usb_driver;
250 	struct usb_dynids	dynids;
251 
252 	unsigned char		num_ports;
253 
254 	unsigned char		num_bulk_in;
255 	unsigned char		num_bulk_out;
256 	unsigned char		num_interrupt_in;
257 	unsigned char		num_interrupt_out;
258 
259 	size_t			bulk_in_size;
260 	size_t			bulk_out_size;
261 
262 	int (*probe)(struct usb_serial *serial, const struct usb_device_id *id);
263 	int (*attach)(struct usb_serial *serial);
264 	int (*calc_num_ports)(struct usb_serial *serial,
265 			struct usb_serial_endpoints *epds);
266 
267 	void (*disconnect)(struct usb_serial *serial);
268 	void (*release)(struct usb_serial *serial);
269 
270 	int (*port_probe)(struct usb_serial_port *port);
271 	int (*port_remove)(struct usb_serial_port *port);
272 
273 	int (*suspend)(struct usb_serial *serial, pm_message_t message);
274 	int (*resume)(struct usb_serial *serial);
275 	int (*reset_resume)(struct usb_serial *serial);
276 
277 	/* serial function calls */
278 	/* Called by console and by the tty layer */
279 	int  (*open)(struct tty_struct *tty, struct usb_serial_port *port);
280 	void (*close)(struct usb_serial_port *port);
281 	int  (*write)(struct tty_struct *tty, struct usb_serial_port *port,
282 			const unsigned char *buf, int count);
283 	/* Called only by the tty layer */
284 	int  (*write_room)(struct tty_struct *tty);
285 	int  (*ioctl)(struct tty_struct *tty,
286 		      unsigned int cmd, unsigned long arg);
287 	void (*set_termios)(struct tty_struct *tty,
288 			struct usb_serial_port *port, struct ktermios *old);
289 	void (*break_ctl)(struct tty_struct *tty, int break_state);
290 	int  (*chars_in_buffer)(struct tty_struct *tty);
291 	void (*wait_until_sent)(struct tty_struct *tty, long timeout);
292 	bool (*tx_empty)(struct usb_serial_port *port);
293 	void (*throttle)(struct tty_struct *tty);
294 	void (*unthrottle)(struct tty_struct *tty);
295 	int  (*tiocmget)(struct tty_struct *tty);
296 	int  (*tiocmset)(struct tty_struct *tty,
297 			 unsigned int set, unsigned int clear);
298 	int  (*tiocmiwait)(struct tty_struct *tty, unsigned long arg);
299 	int  (*get_icount)(struct tty_struct *tty,
300 			struct serial_icounter_struct *icount);
301 	/* Called by the tty layer for port level work. There may or may not
302 	   be an attached tty at this point */
303 	void (*dtr_rts)(struct usb_serial_port *port, int on);
304 	int  (*carrier_raised)(struct usb_serial_port *port);
305 	/* Called by the usb serial hooks to allow the user to rework the
306 	   termios state */
307 	void (*init_termios)(struct tty_struct *tty);
308 	/* USB events */
309 	void (*read_int_callback)(struct urb *urb);
310 	void (*write_int_callback)(struct urb *urb);
311 	void (*read_bulk_callback)(struct urb *urb);
312 	void (*write_bulk_callback)(struct urb *urb);
313 	/* Called by the generic read bulk callback */
314 	void (*process_read_urb)(struct urb *urb);
315 	/* Called by the generic write implementation */
316 	int (*prepare_write_buffer)(struct usb_serial_port *port,
317 						void *dest, size_t size);
318 };
319 #define to_usb_serial_driver(d) \
320 	container_of(d, struct usb_serial_driver, driver)
321 
322 extern int usb_serial_register_drivers(struct usb_serial_driver *const serial_drivers[],
323 		const char *name, const struct usb_device_id *id_table);
324 extern void usb_serial_deregister_drivers(struct usb_serial_driver *const serial_drivers[]);
325 extern void usb_serial_port_softint(struct usb_serial_port *port);
326 
327 extern int usb_serial_suspend(struct usb_interface *intf, pm_message_t message);
328 extern int usb_serial_resume(struct usb_interface *intf);
329 
330 /* USB Serial console functions */
331 #ifdef CONFIG_USB_SERIAL_CONSOLE
332 extern void usb_serial_console_init(int minor);
333 extern void usb_serial_console_exit(void);
334 extern void usb_serial_console_disconnect(struct usb_serial *serial);
335 #else
336 static inline void usb_serial_console_init(int minor) { }
337 static inline void usb_serial_console_exit(void) { }
338 static inline void usb_serial_console_disconnect(struct usb_serial *serial) {}
339 #endif
340 
341 /* Functions needed by other parts of the usbserial core */
342 extern struct usb_serial_port *usb_serial_port_get_by_minor(unsigned int minor);
343 extern void usb_serial_put(struct usb_serial *serial);
344 extern int usb_serial_generic_open(struct tty_struct *tty,
345 	struct usb_serial_port *port);
346 extern int usb_serial_generic_write_start(struct usb_serial_port *port,
347 							gfp_t mem_flags);
348 extern int usb_serial_generic_write(struct tty_struct *tty,
349 	struct usb_serial_port *port, const unsigned char *buf, int count);
350 extern void usb_serial_generic_close(struct usb_serial_port *port);
351 extern int usb_serial_generic_resume(struct usb_serial *serial);
352 extern int usb_serial_generic_write_room(struct tty_struct *tty);
353 extern int usb_serial_generic_chars_in_buffer(struct tty_struct *tty);
354 extern void usb_serial_generic_wait_until_sent(struct tty_struct *tty,
355 								long timeout);
356 extern void usb_serial_generic_read_bulk_callback(struct urb *urb);
357 extern void usb_serial_generic_write_bulk_callback(struct urb *urb);
358 extern void usb_serial_generic_throttle(struct tty_struct *tty);
359 extern void usb_serial_generic_unthrottle(struct tty_struct *tty);
360 extern int usb_serial_generic_tiocmiwait(struct tty_struct *tty,
361 							unsigned long arg);
362 extern int usb_serial_generic_get_icount(struct tty_struct *tty,
363 					struct serial_icounter_struct *icount);
364 extern int usb_serial_generic_register(void);
365 extern void usb_serial_generic_deregister(void);
366 extern int usb_serial_generic_submit_read_urbs(struct usb_serial_port *port,
367 						 gfp_t mem_flags);
368 extern void usb_serial_generic_process_read_urb(struct urb *urb);
369 extern int usb_serial_generic_prepare_write_buffer(struct usb_serial_port *port,
370 						void *dest, size_t size);
371 extern int usb_serial_handle_sysrq_char(struct usb_serial_port *port,
372 					unsigned int ch);
373 extern int usb_serial_handle_break(struct usb_serial_port *port);
374 extern void usb_serial_handle_dcd_change(struct usb_serial_port *usb_port,
375 					 struct tty_struct *tty,
376 					 unsigned int status);
377 
378 
379 extern int usb_serial_bus_register(struct usb_serial_driver *device);
380 extern void usb_serial_bus_deregister(struct usb_serial_driver *device);
381 
382 extern struct bus_type usb_serial_bus_type;
383 extern struct tty_driver *usb_serial_tty_driver;
384 
385 static inline void usb_serial_debug_data(struct device *dev,
386 					 const char *function, int size,
387 					 const unsigned char *data)
388 {
389 	dev_dbg(dev, "%s - length = %d, data = %*ph\n",
390 		function, size, size, data);
391 }
392 
393 /*
394  * Macro for reporting errors in write path to avoid inifinite loop
395  * when port is used as a console.
396  */
397 #define dev_err_console(usport, fmt, ...)				\
398 do {									\
399 	static bool __print_once;					\
400 	struct usb_serial_port *__port = (usport);			\
401 									\
402 	if (!__port->port.console || !__print_once) {			\
403 		__print_once = true;					\
404 		dev_err(&__port->dev, fmt, ##__VA_ARGS__);		\
405 	}								\
406 } while (0)
407 
408 /*
409  * module_usb_serial_driver() - Helper macro for registering a USB Serial driver
410  * @__serial_drivers: list of usb_serial drivers to register
411  * @__ids: all device ids that @__serial_drivers bind to
412  *
413  * Helper macro for USB serial drivers which do not do anything special
414  * in module init/exit. This eliminates a lot of boilerplate. Each
415  * module may only use this macro once, and calling it replaces
416  * module_init() and module_exit()
417  *
418  */
419 #define usb_serial_module_driver(__name, __serial_drivers, __ids)	\
420 static int __init usb_serial_module_init(void)				\
421 {									\
422 	return usb_serial_register_drivers(__serial_drivers,		\
423 					   __name, __ids);		\
424 }									\
425 module_init(usb_serial_module_init);					\
426 static void __exit usb_serial_module_exit(void)				\
427 {									\
428 	usb_serial_deregister_drivers(__serial_drivers);		\
429 }									\
430 module_exit(usb_serial_module_exit);
431 
432 #define module_usb_serial_driver(__serial_drivers, __ids)		\
433 	usb_serial_module_driver(KBUILD_MODNAME, __serial_drivers, __ids)
434 
435 #endif /* __LINUX_USB_SERIAL_H */
436 
437