xref: /linux/include/linux/usb/serial.h (revision a078ccff5642a8fe792a43b3d973bcc3f6dd733f)
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/sysrq.h>
19 #include <linux/kfifo.h>
20 
21 #define SERIAL_TTY_MAJOR	188	/* Nice legal number now */
22 #define SERIAL_TTY_MINORS	254	/* loads of devices :) */
23 #define SERIAL_TTY_NO_MINOR	255	/* No minor was assigned */
24 
25 /* The maximum number of ports one device can grab at once */
26 #define MAX_NUM_PORTS		8
27 
28 /* parity check flag */
29 #define RELEVANT_IFLAG(iflag)	(iflag & (IGNBRK|BRKINT|IGNPAR|PARMRK|INPCK))
30 
31 /* USB serial flags */
32 #define USB_SERIAL_WRITE_BUSY	0
33 
34 /**
35  * usb_serial_port: structure for the specific ports of a device.
36  * @serial: pointer back to the struct usb_serial owner of this port.
37  * @port: pointer to the corresponding tty_port for this port.
38  * @lock: spinlock to grab when updating portions of this structure.
39  * @number: the number of the port (the minor number).
40  * @interrupt_in_buffer: pointer to the interrupt in buffer for this port.
41  * @interrupt_in_urb: pointer to the interrupt in struct urb for this port.
42  * @interrupt_in_endpointAddress: endpoint address for the interrupt in pipe
43  *	for this port.
44  * @interrupt_out_buffer: pointer to the interrupt out buffer for this port.
45  * @interrupt_out_size: the size of the interrupt_out_buffer, in bytes.
46  * @interrupt_out_urb: pointer to the interrupt out struct urb for this port.
47  * @interrupt_out_endpointAddress: endpoint address for the interrupt out pipe
48  *	for this port.
49  * @bulk_in_buffer: pointer to the bulk in buffer for this port.
50  * @bulk_in_size: the size of the bulk_in_buffer, in bytes.
51  * @read_urb: pointer to the bulk in struct urb for this port.
52  * @bulk_in_endpointAddress: endpoint address for the bulk in pipe for this
53  *	port.
54  * @bulk_in_buffers: pointers to the bulk in buffers for this port
55  * @read_urbs: pointers to the bulk in urbs for this port
56  * @read_urbs_free: status bitmap the for bulk in urbs
57  * @bulk_out_buffer: pointer to the bulk out buffer for this port.
58  * @bulk_out_size: the size of the bulk_out_buffer, in bytes.
59  * @write_urb: pointer to the bulk out struct urb for this port.
60  * @write_fifo: kfifo used to buffer outgoing data
61  * @bulk_out_buffers: pointers to the bulk out buffers for this port
62  * @write_urbs: pointers to the bulk out urbs for this port
63  * @write_urbs_free: status bitmap the for bulk out urbs
64  * @tx_bytes: number of bytes currently in host stack queues
65  * @bulk_out_endpointAddress: endpoint address for the bulk out pipe for this
66  *	port.
67  * @flags: usb serial port flags
68  * @write_wait: a wait_queue_head_t used by the port.
69  * @delta_msr_wait: modem-status-change wait queue
70  * @work: work queue entry for the line discipline waking up.
71  * @throttled: nonzero if the read urb is inactive to throttle the device
72  * @throttle_req: nonzero if the tty wants to throttle us
73  * @dev: pointer to the serial device
74  *
75  * This structure is used by the usb-serial core and drivers for the specific
76  * ports of a device.
77  */
78 struct usb_serial_port {
79 	struct usb_serial	*serial;
80 	struct tty_port		port;
81 	spinlock_t		lock;
82 	unsigned char		number;
83 
84 	unsigned char		*interrupt_in_buffer;
85 	struct urb		*interrupt_in_urb;
86 	__u8			interrupt_in_endpointAddress;
87 
88 	unsigned char		*interrupt_out_buffer;
89 	int			interrupt_out_size;
90 	struct urb		*interrupt_out_urb;
91 	__u8			interrupt_out_endpointAddress;
92 
93 	unsigned char		*bulk_in_buffer;
94 	int			bulk_in_size;
95 	struct urb		*read_urb;
96 	__u8			bulk_in_endpointAddress;
97 
98 	unsigned char		*bulk_in_buffers[2];
99 	struct urb		*read_urbs[2];
100 	unsigned long		read_urbs_free;
101 
102 	unsigned char		*bulk_out_buffer;
103 	int			bulk_out_size;
104 	struct urb		*write_urb;
105 	struct kfifo		write_fifo;
106 
107 	unsigned char		*bulk_out_buffers[2];
108 	struct urb		*write_urbs[2];
109 	unsigned long		write_urbs_free;
110 	__u8			bulk_out_endpointAddress;
111 
112 	int			tx_bytes;
113 
114 	unsigned long		flags;
115 	wait_queue_head_t	write_wait;
116 	wait_queue_head_t	delta_msr_wait;
117 	struct work_struct	work;
118 	char			throttled;
119 	char			throttle_req;
120 	unsigned long		sysrq; /* sysrq timeout */
121 	struct device		dev;
122 };
123 #define to_usb_serial_port(d) container_of(d, struct usb_serial_port, dev)
124 
125 /* get and set the port private data pointer helper functions */
126 static inline void *usb_get_serial_port_data(struct usb_serial_port *port)
127 {
128 	return dev_get_drvdata(&port->dev);
129 }
130 
131 static inline void usb_set_serial_port_data(struct usb_serial_port *port,
132 					    void *data)
133 {
134 	dev_set_drvdata(&port->dev, data);
135 }
136 
137 /**
138  * usb_serial - structure used by the usb-serial core for a device
139  * @dev: pointer to the struct usb_device for this device
140  * @type: pointer to the struct usb_serial_driver for this device
141  * @interface: pointer to the struct usb_interface for this device
142  * @minor: the starting minor number for this device
143  * @num_ports: the number of ports this device has
144  * @num_interrupt_in: number of interrupt in endpoints we have
145  * @num_interrupt_out: number of interrupt out endpoints we have
146  * @num_bulk_in: number of bulk in endpoints we have
147  * @num_bulk_out: number of bulk out endpoints we have
148  * @port: array of struct usb_serial_port structures for the different ports.
149  * @private: place to put any driver specific information that is needed.  The
150  *	usb-serial driver is required to manage this data, the usb-serial core
151  *	will not touch this.  Use usb_get_serial_data() and
152  *	usb_set_serial_data() to access this.
153  */
154 struct usb_serial {
155 	struct usb_device		*dev;
156 	struct usb_serial_driver	*type;
157 	struct usb_interface		*interface;
158 	unsigned char			disconnected:1;
159 	unsigned char			suspending:1;
160 	unsigned char			attached:1;
161 	unsigned char			minor;
162 	unsigned char			num_ports;
163 	unsigned char			num_port_pointers;
164 	char				num_interrupt_in;
165 	char				num_interrupt_out;
166 	char				num_bulk_in;
167 	char				num_bulk_out;
168 	struct usb_serial_port		*port[MAX_NUM_PORTS];
169 	struct kref			kref;
170 	struct mutex			disc_mutex;
171 	void				*private;
172 };
173 #define to_usb_serial(d) container_of(d, struct usb_serial, kref)
174 
175 /* get and set the serial private data pointer helper functions */
176 static inline void *usb_get_serial_data(struct usb_serial *serial)
177 {
178 	return serial->private;
179 }
180 
181 static inline void usb_set_serial_data(struct usb_serial *serial, void *data)
182 {
183 	serial->private = data;
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  * @bulk_in_size: minimum number of bytes to allocate for bulk-in buffer
194  *	(0 = end-point size)
195  * @bulk_out_size: bytes to allocate for bulk-out buffer (0 = end-point size)
196  * @calc_num_ports: pointer to a function to determine how many ports this
197  *	device has dynamically.  It will be called after the probe()
198  *	callback is called, but before attach()
199  * @probe: pointer to the driver's probe function.
200  *	This will be called when the device is inserted into the system,
201  *	but before the device has been fully initialized by the usb_serial
202  *	subsystem.  Use this function to download any firmware to the device,
203  *	or any other early initialization that might be needed.
204  *	Return 0 to continue on with the initialization sequence.  Anything
205  *	else will abort it.
206  * @attach: pointer to the driver's attach function.
207  *	This will be called when the struct usb_serial structure is fully set
208  *	set up.  Do any local initialization of the device, or any private
209  *	memory structure allocation at this point in time.
210  * @disconnect: pointer to the driver's disconnect function.  This will be
211  *	called when the device is unplugged or unbound from the driver.
212  * @release: pointer to the driver's release function.  This will be called
213  *	when the usb_serial data structure is about to be destroyed.
214  * @usb_driver: pointer to the struct usb_driver that controls this
215  *	device.  This is necessary to allow dynamic ids to be added to
216  *	the driver from sysfs.
217  *
218  * This structure is defines a USB Serial driver.  It provides all of
219  * the information that the USB serial core code needs.  If the function
220  * pointers are defined, then the USB serial core code will call them when
221  * the corresponding tty port functions are called.  If they are not
222  * called, the generic serial function will be used instead.
223  *
224  * The driver.owner field should be set to the module owner of this driver.
225  * The driver.name field should be set to the name of this driver (remember
226  * it will show up in sysfs, so it needs to be short and to the point.
227  * Using the module name is a good idea.)
228  */
229 struct usb_serial_driver {
230 	const char *description;
231 	const struct usb_device_id *id_table;
232 	char	num_ports;
233 
234 	struct list_head	driver_list;
235 	struct device_driver	driver;
236 	struct usb_driver	*usb_driver;
237 	struct usb_dynids	dynids;
238 
239 	size_t			bulk_in_size;
240 	size_t			bulk_out_size;
241 
242 	int (*probe)(struct usb_serial *serial, const struct usb_device_id *id);
243 	int (*attach)(struct usb_serial *serial);
244 	int (*calc_num_ports) (struct usb_serial *serial);
245 
246 	void (*disconnect)(struct usb_serial *serial);
247 	void (*release)(struct usb_serial *serial);
248 
249 	int (*port_probe)(struct usb_serial_port *port);
250 	int (*port_remove)(struct usb_serial_port *port);
251 
252 	int (*suspend)(struct usb_serial *serial, pm_message_t message);
253 	int (*resume)(struct usb_serial *serial);
254 	int (*reset_resume)(struct usb_serial *serial);
255 
256 	/* serial function calls */
257 	/* Called by console and by the tty layer */
258 	int  (*open)(struct tty_struct *tty, struct usb_serial_port *port);
259 	void (*close)(struct usb_serial_port *port);
260 	int  (*write)(struct tty_struct *tty, struct usb_serial_port *port,
261 			const unsigned char *buf, int count);
262 	/* Called only by the tty layer */
263 	int  (*write_room)(struct tty_struct *tty);
264 	int  (*ioctl)(struct tty_struct *tty,
265 		      unsigned int cmd, unsigned long arg);
266 	void (*set_termios)(struct tty_struct *tty,
267 			struct usb_serial_port *port, struct ktermios *old);
268 	void (*break_ctl)(struct tty_struct *tty, int break_state);
269 	int  (*chars_in_buffer)(struct tty_struct *tty);
270 	void (*throttle)(struct tty_struct *tty);
271 	void (*unthrottle)(struct tty_struct *tty);
272 	int  (*tiocmget)(struct tty_struct *tty);
273 	int  (*tiocmset)(struct tty_struct *tty,
274 			 unsigned int set, unsigned int clear);
275 	int  (*get_icount)(struct tty_struct *tty,
276 			struct serial_icounter_struct *icount);
277 	/* Called by the tty layer for port level work. There may or may not
278 	   be an attached tty at this point */
279 	void (*dtr_rts)(struct usb_serial_port *port, int on);
280 	int  (*carrier_raised)(struct usb_serial_port *port);
281 	/* Called by the usb serial hooks to allow the user to rework the
282 	   termios state */
283 	void (*init_termios)(struct tty_struct *tty);
284 	/* USB events */
285 	void (*read_int_callback)(struct urb *urb);
286 	void (*write_int_callback)(struct urb *urb);
287 	void (*read_bulk_callback)(struct urb *urb);
288 	void (*write_bulk_callback)(struct urb *urb);
289 	/* Called by the generic read bulk callback */
290 	void (*process_read_urb)(struct urb *urb);
291 	/* Called by the generic write implementation */
292 	int (*prepare_write_buffer)(struct usb_serial_port *port,
293 						void *dest, size_t size);
294 };
295 #define to_usb_serial_driver(d) \
296 	container_of(d, struct usb_serial_driver, driver)
297 
298 extern int usb_serial_register_drivers(struct usb_serial_driver *const serial_drivers[],
299 		const char *name, const struct usb_device_id *id_table);
300 extern void usb_serial_deregister_drivers(struct usb_serial_driver *const serial_drivers[]);
301 extern void usb_serial_port_softint(struct usb_serial_port *port);
302 
303 extern int usb_serial_suspend(struct usb_interface *intf, pm_message_t message);
304 extern int usb_serial_resume(struct usb_interface *intf);
305 
306 /* USB Serial console functions */
307 #ifdef CONFIG_USB_SERIAL_CONSOLE
308 extern void usb_serial_console_init(int minor);
309 extern void usb_serial_console_exit(void);
310 extern void usb_serial_console_disconnect(struct usb_serial *serial);
311 #else
312 static inline void usb_serial_console_init(int minor) { }
313 static inline void usb_serial_console_exit(void) { }
314 static inline void usb_serial_console_disconnect(struct usb_serial *serial) {}
315 #endif
316 
317 /* Functions needed by other parts of the usbserial core */
318 extern struct usb_serial *usb_serial_get_by_index(unsigned int minor);
319 extern void usb_serial_put(struct usb_serial *serial);
320 extern int usb_serial_generic_open(struct tty_struct *tty,
321 	struct usb_serial_port *port);
322 extern int usb_serial_generic_write(struct tty_struct *tty,
323 	struct usb_serial_port *port, const unsigned char *buf, int count);
324 extern void usb_serial_generic_close(struct usb_serial_port *port);
325 extern int usb_serial_generic_resume(struct usb_serial *serial);
326 extern int usb_serial_generic_write_room(struct tty_struct *tty);
327 extern int usb_serial_generic_chars_in_buffer(struct tty_struct *tty);
328 extern void usb_serial_generic_read_bulk_callback(struct urb *urb);
329 extern void usb_serial_generic_write_bulk_callback(struct urb *urb);
330 extern void usb_serial_generic_throttle(struct tty_struct *tty);
331 extern void usb_serial_generic_unthrottle(struct tty_struct *tty);
332 extern void usb_serial_generic_disconnect(struct usb_serial *serial);
333 extern void usb_serial_generic_release(struct usb_serial *serial);
334 extern int usb_serial_generic_register(void);
335 extern void usb_serial_generic_deregister(void);
336 extern int usb_serial_generic_submit_read_urbs(struct usb_serial_port *port,
337 						 gfp_t mem_flags);
338 extern void usb_serial_generic_process_read_urb(struct urb *urb);
339 extern int usb_serial_generic_prepare_write_buffer(struct usb_serial_port *port,
340 						void *dest, size_t size);
341 extern int usb_serial_handle_sysrq_char(struct usb_serial_port *port,
342 					unsigned int ch);
343 extern int usb_serial_handle_break(struct usb_serial_port *port);
344 extern void usb_serial_handle_dcd_change(struct usb_serial_port *usb_port,
345 					 struct tty_struct *tty,
346 					 unsigned int status);
347 
348 
349 extern int usb_serial_bus_register(struct usb_serial_driver *device);
350 extern void usb_serial_bus_deregister(struct usb_serial_driver *device);
351 
352 extern struct usb_serial_driver usb_serial_generic_device;
353 extern struct bus_type usb_serial_bus_type;
354 extern struct tty_driver *usb_serial_tty_driver;
355 
356 static inline void usb_serial_debug_data(struct device *dev,
357 					 const char *function, int size,
358 					 const unsigned char *data)
359 {
360 	dev_dbg(dev, "%s - length = %d, data = %*ph\n",
361 		function, size, size, data);
362 }
363 
364 /*
365  * Macro for reporting errors in write path to avoid inifinite loop
366  * when port is used as a console.
367  */
368 #define dev_err_console(usport, fmt, ...)				\
369 do {									\
370 	static bool __print_once;					\
371 	struct usb_serial_port *__port = (usport);			\
372 									\
373 	if (!__port->port.console || !__print_once) {			\
374 		__print_once = true;					\
375 		dev_err(&__port->dev, fmt, ##__VA_ARGS__);		\
376 	}								\
377 } while (0)
378 
379 /*
380  * module_usb_serial_driver() - Helper macro for registering a USB Serial driver
381  * @__serial_drivers: list of usb_serial drivers to register
382  * @__ids: all device ids that @__serial_drivers bind to
383  *
384  * Helper macro for USB serial drivers which do not do anything special
385  * in module init/exit. This eliminates a lot of boilerplate. Each
386  * module may only use this macro once, and calling it replaces
387  * module_init() and module_exit()
388  *
389  */
390 #define usb_serial_module_driver(__name, __serial_drivers, __ids)	\
391 static int __init usb_serial_module_init(void)				\
392 {									\
393 	return usb_serial_register_drivers(__serial_drivers,		\
394 					   __name, __ids);		\
395 }									\
396 module_init(usb_serial_module_init);					\
397 static void __exit usb_serial_module_exit(void)				\
398 {									\
399 	usb_serial_deregister_drivers(__serial_drivers);		\
400 }									\
401 module_exit(usb_serial_module_exit);
402 
403 #define module_usb_serial_driver(__serial_drivers, __ids)		\
404 	usb_serial_module_driver(KBUILD_MODNAME, __serial_drivers, __ids)
405 
406 #endif /* __LINUX_USB_SERIAL_H */
407 
408