xref: /openbmc/linux/drivers/usb/serial/cypress_m8.c (revision 9ac8d3fb)
1 /*
2  * USB Cypress M8 driver
3  *
4  * 	Copyright (C) 2004
5  * 	    Lonnie Mendez (dignome@gmail.com)
6  *	Copyright (C) 2003,2004
7  *	    Neil Whelchel (koyama@firstlight.net)
8  *
9  * 	This program is free software; you can redistribute it and/or modify
10  * 	it under the terms of the GNU General Public License as published by
11  * 	the Free Software Foundation; either version 2 of the License, or
12  * 	(at your option) any later version.
13  *
14  * See Documentation/usb/usb-serial.txt for more information on using this
15  * driver
16  *
17  * See http://geocities.com/i0xox0i for information on this driver and the
18  * earthmate usb device.
19  *
20  *  Lonnie Mendez <dignome@gmail.com>
21  *  4-29-2005
22  *	Fixed problem where setting or retreiving the serial config would fail
23  *	with EPIPE.  Removed CRTS toggling so the driver behaves more like
24  *	other usbserial adapters.  Issued new interval of 1ms instead of the
25  *	default 10ms.  As a result, transfer speed has been substantially
26  *	increased from avg. 850bps to avg. 3300bps.  initial termios has also
27  *	been modified.  Cleaned up code and formatting issues so it is more
28  *	readable.  Replaced the C++ style comments.
29  *
30  *  Lonnie Mendez <dignome@gmail.com>
31  *  12-15-2004
32  *	Incorporated write buffering from pl2303 driver.  Fixed bug with line
33  *	handling so both lines are raised in cypress_open. (was dropping rts)
34  *      Various code cleanups made as well along with other misc bug fixes.
35  *
36  *  Lonnie Mendez <dignome@gmail.com>
37  *  04-10-2004
38  *	Driver modified to support dynamic line settings.  Various improvments
39  *      and features.
40  *
41  *  Neil Whelchel
42  *  10-2003
43  *	Driver first released.
44  *
45  */
46 
47 /* Thanks to Neil Whelchel for writing the first cypress m8 implementation
48    for linux. */
49 /* Thanks to cypress for providing references for the hid reports. */
50 /* Thanks to Jiang Zhang for providing links and for general help. */
51 /* Code originates and was built up from ftdi_sio, belkin, pl2303 and others.*/
52 
53 
54 #include <linux/kernel.h>
55 #include <linux/errno.h>
56 #include <linux/init.h>
57 #include <linux/slab.h>
58 #include <linux/tty.h>
59 #include <linux/tty_driver.h>
60 #include <linux/tty_flip.h>
61 #include <linux/module.h>
62 #include <linux/moduleparam.h>
63 #include <linux/spinlock.h>
64 #include <linux/usb.h>
65 #include <linux/usb/serial.h>
66 #include <linux/serial.h>
67 #include <linux/delay.h>
68 #include <linux/uaccess.h>
69 
70 #include "cypress_m8.h"
71 
72 
73 #ifdef CONFIG_USB_SERIAL_DEBUG
74 	static int debug = 1;
75 #else
76 	static int debug;
77 #endif
78 static int stats;
79 static int interval;
80 
81 /*
82  * Version Information
83  */
84 #define DRIVER_VERSION "v1.09"
85 #define DRIVER_AUTHOR "Lonnie Mendez <dignome@gmail.com>, Neil Whelchel <koyama@firstlight.net>"
86 #define DRIVER_DESC "Cypress USB to Serial Driver"
87 
88 /* write buffer size defines */
89 #define CYPRESS_BUF_SIZE	1024
90 #define CYPRESS_CLOSING_WAIT	(30*HZ)
91 
92 static struct usb_device_id id_table_earthmate [] = {
93 	{ USB_DEVICE(VENDOR_ID_DELORME, PRODUCT_ID_EARTHMATEUSB) },
94 	{ USB_DEVICE(VENDOR_ID_DELORME, PRODUCT_ID_EARTHMATEUSB_LT20) },
95 	{ }						/* Terminating entry */
96 };
97 
98 static struct usb_device_id id_table_cyphidcomrs232 [] = {
99 	{ USB_DEVICE(VENDOR_ID_CYPRESS, PRODUCT_ID_CYPHIDCOM) },
100 	{ USB_DEVICE(VENDOR_ID_POWERCOM, PRODUCT_ID_UPS) },
101 	{ }						/* Terminating entry */
102 };
103 
104 static struct usb_device_id id_table_nokiaca42v2 [] = {
105 	{ USB_DEVICE(VENDOR_ID_DAZZLE, PRODUCT_ID_CA42) },
106 	{ }						/* Terminating entry */
107 };
108 
109 static struct usb_device_id id_table_combined [] = {
110 	{ USB_DEVICE(VENDOR_ID_DELORME, PRODUCT_ID_EARTHMATEUSB) },
111 	{ USB_DEVICE(VENDOR_ID_DELORME, PRODUCT_ID_EARTHMATEUSB_LT20) },
112 	{ USB_DEVICE(VENDOR_ID_CYPRESS, PRODUCT_ID_CYPHIDCOM) },
113 	{ USB_DEVICE(VENDOR_ID_POWERCOM, PRODUCT_ID_UPS) },
114 	{ USB_DEVICE(VENDOR_ID_DAZZLE, PRODUCT_ID_CA42) },
115 	{ }						/* Terminating entry */
116 };
117 
118 MODULE_DEVICE_TABLE(usb, id_table_combined);
119 
120 static struct usb_driver cypress_driver = {
121 	.name =		"cypress",
122 	.probe =	usb_serial_probe,
123 	.disconnect =	usb_serial_disconnect,
124 	.id_table =	id_table_combined,
125 	.no_dynamic_id = 	1,
126 };
127 
128 enum packet_format {
129 	packet_format_1,  /* b0:status, b1:payload count */
130 	packet_format_2   /* b0[7:3]:status, b0[2:0]:payload count */
131 };
132 
133 struct cypress_private {
134 	spinlock_t lock;		   /* private lock */
135 	int chiptype;			   /* identifier of device, for quirks/etc */
136 	int bytes_in;			   /* used for statistics */
137 	int bytes_out;			   /* used for statistics */
138 	int cmd_count;			   /* used for statistics */
139 	int cmd_ctrl;			   /* always set this to 1 before issuing a command */
140 	struct cypress_buf *buf;	   /* write buffer */
141 	int write_urb_in_use;		   /* write urb in use indicator */
142 	int write_urb_interval;            /* interval to use for write urb */
143 	int read_urb_interval;             /* interval to use for read urb */
144 	int comm_is_ok;                    /* true if communication is (still) ok */
145 	int termios_initialized;
146 	__u8 line_control;	   	   /* holds dtr / rts value */
147 	__u8 current_status;	   	   /* received from last read - info on dsr,cts,cd,ri,etc */
148 	__u8 current_config;	   	   /* stores the current configuration byte */
149 	__u8 rx_flags;			   /* throttling - used from whiteheat/ftdi_sio */
150 	enum packet_format pkt_fmt;	   /* format to use for packet send / receive */
151 	int get_cfg_unsafe;		   /* If true, the CYPRESS_GET_CONFIG is unsafe */
152 	int baud_rate;			   /* stores current baud rate in
153 					      integer form */
154 	int isthrottled;		   /* if throttled, discard reads */
155 	wait_queue_head_t delta_msr_wait;  /* used for TIOCMIWAIT */
156 	char prev_status, diff_status;	   /* used for TIOCMIWAIT */
157 	/* we pass a pointer to this as the arguement sent to
158 	   cypress_set_termios old_termios */
159 	struct ktermios tmp_termios; 	   /* stores the old termios settings */
160 };
161 
162 /* write buffer structure */
163 struct cypress_buf {
164 	unsigned int	buf_size;
165 	char		*buf_buf;
166 	char		*buf_get;
167 	char		*buf_put;
168 };
169 
170 /* function prototypes for the Cypress USB to serial device */
171 static int  cypress_earthmate_startup(struct usb_serial *serial);
172 static int  cypress_hidcom_startup(struct usb_serial *serial);
173 static int  cypress_ca42v2_startup(struct usb_serial *serial);
174 static void cypress_shutdown(struct usb_serial *serial);
175 static int  cypress_open(struct tty_struct *tty,
176 			struct usb_serial_port *port, struct file *filp);
177 static void cypress_close(struct tty_struct *tty,
178 			struct usb_serial_port *port, struct file *filp);
179 static int  cypress_write(struct tty_struct *tty, struct usb_serial_port *port,
180 			const unsigned char *buf, int count);
181 static void cypress_send(struct usb_serial_port *port);
182 static int  cypress_write_room(struct tty_struct *tty);
183 static int  cypress_ioctl(struct tty_struct *tty, struct file *file,
184 			unsigned int cmd, unsigned long arg);
185 static void cypress_set_termios(struct tty_struct *tty,
186 			struct usb_serial_port *port, struct ktermios *old);
187 static int  cypress_tiocmget(struct tty_struct *tty, struct file *file);
188 static int  cypress_tiocmset(struct tty_struct *tty, struct file *file,
189 			unsigned int set, unsigned int clear);
190 static int  cypress_chars_in_buffer(struct tty_struct *tty);
191 static void cypress_throttle(struct tty_struct *tty);
192 static void cypress_unthrottle(struct tty_struct *tty);
193 static void cypress_set_dead(struct usb_serial_port *port);
194 static void cypress_read_int_callback(struct urb *urb);
195 static void cypress_write_int_callback(struct urb *urb);
196 /* write buffer functions */
197 static struct cypress_buf *cypress_buf_alloc(unsigned int size);
198 static void cypress_buf_free(struct cypress_buf *cb);
199 static void cypress_buf_clear(struct cypress_buf *cb);
200 static unsigned int cypress_buf_data_avail(struct cypress_buf *cb);
201 static unsigned int cypress_buf_space_avail(struct cypress_buf *cb);
202 static unsigned int cypress_buf_put(struct cypress_buf *cb,
203 					const char *buf, unsigned int count);
204 static unsigned int cypress_buf_get(struct cypress_buf *cb,
205 					char *buf, unsigned int count);
206 
207 
208 static struct usb_serial_driver cypress_earthmate_device = {
209 	.driver = {
210 		.owner =		THIS_MODULE,
211 		.name =			"earthmate",
212 	},
213 	.description =			"DeLorme Earthmate USB",
214 	.usb_driver = 			&cypress_driver,
215 	.id_table =			id_table_earthmate,
216 	.num_ports =			1,
217 	.attach =			cypress_earthmate_startup,
218 	.shutdown =			cypress_shutdown,
219 	.open =				cypress_open,
220 	.close =			cypress_close,
221 	.write =			cypress_write,
222 	.write_room =			cypress_write_room,
223 	.ioctl =			cypress_ioctl,
224 	.set_termios =			cypress_set_termios,
225 	.tiocmget =			cypress_tiocmget,
226 	.tiocmset =			cypress_tiocmset,
227 	.chars_in_buffer =		cypress_chars_in_buffer,
228 	.throttle =		 	cypress_throttle,
229 	.unthrottle =			cypress_unthrottle,
230 	.read_int_callback =		cypress_read_int_callback,
231 	.write_int_callback =		cypress_write_int_callback,
232 };
233 
234 static struct usb_serial_driver cypress_hidcom_device = {
235 	.driver = {
236 		.owner =		THIS_MODULE,
237 		.name =			"cyphidcom",
238 	},
239 	.description =			"HID->COM RS232 Adapter",
240 	.usb_driver = 			&cypress_driver,
241 	.id_table =			id_table_cyphidcomrs232,
242 	.num_ports =			1,
243 	.attach =			cypress_hidcom_startup,
244 	.shutdown =			cypress_shutdown,
245 	.open =				cypress_open,
246 	.close =			cypress_close,
247 	.write =			cypress_write,
248 	.write_room =			cypress_write_room,
249 	.ioctl =			cypress_ioctl,
250 	.set_termios =			cypress_set_termios,
251 	.tiocmget =			cypress_tiocmget,
252 	.tiocmset =			cypress_tiocmset,
253 	.chars_in_buffer =		cypress_chars_in_buffer,
254 	.throttle =			cypress_throttle,
255 	.unthrottle =			cypress_unthrottle,
256 	.read_int_callback =		cypress_read_int_callback,
257 	.write_int_callback =		cypress_write_int_callback,
258 };
259 
260 static struct usb_serial_driver cypress_ca42v2_device = {
261 	.driver = {
262 		.owner =		THIS_MODULE,
263 		.name =			"nokiaca42v2",
264 	},
265 	.description =			"Nokia CA-42 V2 Adapter",
266 	.usb_driver = 			&cypress_driver,
267 	.id_table =			id_table_nokiaca42v2,
268 	.num_ports =			1,
269 	.attach =			cypress_ca42v2_startup,
270 	.shutdown =			cypress_shutdown,
271 	.open =				cypress_open,
272 	.close =			cypress_close,
273 	.write =			cypress_write,
274 	.write_room =			cypress_write_room,
275 	.ioctl =			cypress_ioctl,
276 	.set_termios =			cypress_set_termios,
277 	.tiocmget =			cypress_tiocmget,
278 	.tiocmset =			cypress_tiocmset,
279 	.chars_in_buffer =		cypress_chars_in_buffer,
280 	.throttle =			cypress_throttle,
281 	.unthrottle =			cypress_unthrottle,
282 	.read_int_callback =		cypress_read_int_callback,
283 	.write_int_callback =		cypress_write_int_callback,
284 };
285 
286 /*****************************************************************************
287  * Cypress serial helper functions
288  *****************************************************************************/
289 
290 
291 static int analyze_baud_rate(struct usb_serial_port *port, speed_t new_rate)
292 {
293 	struct cypress_private *priv;
294 	priv = usb_get_serial_port_data(port);
295 
296 	/*
297 	 * The general purpose firmware for the Cypress M8 allows for
298 	 * a maximum speed of 57600bps (I have no idea whether DeLorme
299 	 * chose to use the general purpose firmware or not), if you
300 	 * need to modify this speed setting for your own project
301 	 * please add your own chiptype and modify the code likewise.
302 	 * The Cypress HID->COM device will work successfully up to
303 	 * 115200bps (but the actual throughput is around 3kBps).
304 	 */
305 	if (port->serial->dev->speed == USB_SPEED_LOW) {
306 		/*
307 		 * Mike Isely <isely@pobox.com> 2-Feb-2008: The
308 		 * Cypress app note that describes this mechanism
309 		 * states the the low-speed part can't handle more
310 		 * than 800 bytes/sec, in which case 4800 baud is the
311 		 * safest speed for a part like that.
312 		 */
313 		if (new_rate > 4800) {
314 			dbg("%s - failed setting baud rate, device incapable "
315 			    "speed %d", __func__, new_rate);
316 			return -1;
317 		}
318 	}
319 	switch (priv->chiptype) {
320 	case CT_EARTHMATE:
321 		if (new_rate <= 600) {
322 			/* 300 and 600 baud rates are supported under
323 			 * the generic firmware, but are not used with
324 			 * NMEA and SiRF protocols */
325 			dbg("%s - failed setting baud rate, unsupported speed "
326 			    "of %d on Earthmate GPS", __func__, new_rate);
327 			return -1;
328 		}
329 		break;
330 	default:
331 		break;
332 	}
333 	return new_rate;
334 }
335 
336 
337 /* This function can either set or retrieve the current serial line settings */
338 static int cypress_serial_control(struct tty_struct *tty,
339 	struct usb_serial_port *port, speed_t baud_rate, int data_bits,
340 	int stop_bits, int parity_enable, int parity_type, int reset,
341 	int cypress_request_type)
342 {
343 	int new_baudrate = 0, retval = 0, tries = 0;
344 	struct cypress_private *priv;
345 	__u8 feature_buffer[5];
346 	unsigned long flags;
347 
348 	dbg("%s", __func__);
349 
350 	priv = usb_get_serial_port_data(port);
351 
352 	if (!priv->comm_is_ok)
353 		return -ENODEV;
354 
355 	switch (cypress_request_type) {
356 	case CYPRESS_SET_CONFIG:
357 		new_baudrate = priv->baud_rate;
358 		/* 0 means 'Hang up' so doesn't change the true bit rate */
359 		if (baud_rate == 0)
360 			new_baudrate = priv->baud_rate;
361 		/* Change of speed ? */
362 		else if (baud_rate != priv->baud_rate) {
363 			dbg("%s - baud rate is changing", __func__);
364 			retval = analyze_baud_rate(port, baud_rate);
365 			if (retval >=  0) {
366 				new_baudrate = retval;
367 				dbg("%s - New baud rate set to %d",
368 				    __func__, new_baudrate);
369 			}
370 		}
371 		dbg("%s - baud rate is being sent as %d",
372 					__func__, new_baudrate);
373 
374 		memset(feature_buffer, 0, sizeof(feature_buffer));
375 		/* fill the feature_buffer with new configuration */
376 		*((u_int32_t *)feature_buffer) = new_baudrate;
377 		feature_buffer[4] |= data_bits;   /* assign data bits in 2 bit space ( max 3 ) */
378 		/* 1 bit gap */
379 		feature_buffer[4] |= (stop_bits << 3);   /* assign stop bits in 1 bit space */
380 		feature_buffer[4] |= (parity_enable << 4);   /* assign parity flag in 1 bit space */
381 		feature_buffer[4] |= (parity_type << 5);   /* assign parity type in 1 bit space */
382 		/* 1 bit gap */
383 		feature_buffer[4] |= (reset << 7);   /* assign reset at end of byte, 1 bit space */
384 
385 		dbg("%s - device is being sent this feature report:",
386 								__func__);
387 		dbg("%s - %02X - %02X - %02X - %02X - %02X", __func__,
388 			feature_buffer[0], feature_buffer[1],
389 			feature_buffer[2], feature_buffer[3],
390 			feature_buffer[4]);
391 
392 		do {
393 			retval = usb_control_msg(port->serial->dev,
394 					usb_sndctrlpipe(port->serial->dev, 0),
395 					HID_REQ_SET_REPORT,
396 					USB_DIR_OUT | USB_RECIP_INTERFACE | USB_TYPE_CLASS,
397 					0x0300, 0, feature_buffer,
398 					sizeof(feature_buffer), 500);
399 
400 			if (tries++ >= 3)
401 				break;
402 
403 		} while (retval != sizeof(feature_buffer) &&
404 			 retval != -ENODEV);
405 
406 		if (retval != sizeof(feature_buffer)) {
407 			dev_err(&port->dev, "%s - failed sending serial "
408 				"line settings - %d\n", __func__, retval);
409 			cypress_set_dead(port);
410 		} else {
411 			spin_lock_irqsave(&priv->lock, flags);
412 			priv->baud_rate = new_baudrate;
413 			priv->current_config = feature_buffer[4];
414 			spin_unlock_irqrestore(&priv->lock, flags);
415 			/* If we asked for a speed change encode it */
416 			if (baud_rate)
417 				tty_encode_baud_rate(tty,
418 					new_baudrate, new_baudrate);
419 		}
420 	break;
421 	case CYPRESS_GET_CONFIG:
422 		if (priv->get_cfg_unsafe) {
423 			/* Not implemented for this device,
424 			   and if we try to do it we're likely
425 			   to crash the hardware. */
426 			return -ENOTTY;
427 		}
428 		dbg("%s - retreiving serial line settings", __func__);
429 		/* set initial values in feature buffer */
430 		memset(feature_buffer, 0, sizeof(feature_buffer));
431 
432 		do {
433 			retval = usb_control_msg(port->serial->dev,
434 					usb_rcvctrlpipe(port->serial->dev, 0),
435 					HID_REQ_GET_REPORT,
436 					USB_DIR_IN | USB_RECIP_INTERFACE | USB_TYPE_CLASS,
437 					0x0300, 0, feature_buffer,
438 					sizeof(feature_buffer), 500);
439 
440 			if (tries++ >= 3)
441 				break;
442 		} while (retval != sizeof(feature_buffer)
443 						&& retval != -ENODEV);
444 
445 		if (retval != sizeof(feature_buffer)) {
446 			dev_err(&port->dev, "%s - failed to retrieve serial "
447 				"line settings - %d\n", __func__, retval);
448 			cypress_set_dead(port);
449 			return retval;
450 		} else {
451 			spin_lock_irqsave(&priv->lock, flags);
452 			/* store the config in one byte, and later
453 			   use bit masks to check values */
454 			priv->current_config = feature_buffer[4];
455 			priv->baud_rate = *((u_int32_t *)feature_buffer);
456 			spin_unlock_irqrestore(&priv->lock, flags);
457 		}
458 	}
459 	spin_lock_irqsave(&priv->lock, flags);
460 	++priv->cmd_count;
461 	spin_unlock_irqrestore(&priv->lock, flags);
462 
463 	return retval;
464 } /* cypress_serial_control */
465 
466 
467 static void cypress_set_dead(struct usb_serial_port *port)
468 {
469 	struct cypress_private *priv = usb_get_serial_port_data(port);
470 	unsigned long flags;
471 
472 	spin_lock_irqsave(&priv->lock, flags);
473 	if (!priv->comm_is_ok) {
474 		spin_unlock_irqrestore(&priv->lock, flags);
475 		return;
476 	}
477 	priv->comm_is_ok = 0;
478 	spin_unlock_irqrestore(&priv->lock, flags);
479 
480 	dev_err(&port->dev, "cypress_m8 suspending failing port %d - "
481 		"interval might be too short\n", port->number);
482 }
483 
484 
485 /*****************************************************************************
486  * Cypress serial driver functions
487  *****************************************************************************/
488 
489 
490 static int generic_startup(struct usb_serial *serial)
491 {
492 	struct cypress_private *priv;
493 	struct usb_serial_port *port = serial->port[0];
494 
495 	dbg("%s - port %d", __func__, port->number);
496 
497 	priv = kzalloc(sizeof(struct cypress_private), GFP_KERNEL);
498 	if (!priv)
499 		return -ENOMEM;
500 
501 	priv->comm_is_ok = !0;
502 	spin_lock_init(&priv->lock);
503 	priv->buf = cypress_buf_alloc(CYPRESS_BUF_SIZE);
504 	if (priv->buf == NULL) {
505 		kfree(priv);
506 		return -ENOMEM;
507 	}
508 	init_waitqueue_head(&priv->delta_msr_wait);
509 
510 	usb_reset_configuration(serial->dev);
511 
512 	priv->cmd_ctrl = 0;
513 	priv->line_control = 0;
514 	priv->termios_initialized = 0;
515 	priv->rx_flags = 0;
516 	/* Default packet format setting is determined by packet size.
517 	   Anything with a size larger then 9 must have a separate
518 	   count field since the 3 bit count field is otherwise too
519 	   small.  Otherwise we can use the slightly more compact
520 	   format.  This is in accordance with the cypress_m8 serial
521 	   converter app note. */
522 	if (port->interrupt_out_size > 9)
523 		priv->pkt_fmt = packet_format_1;
524 	else
525 		priv->pkt_fmt = packet_format_2;
526 
527 	if (interval > 0) {
528 		priv->write_urb_interval = interval;
529 		priv->read_urb_interval = interval;
530 		dbg("%s - port %d read & write intervals forced to %d",
531 		    __func__, port->number, interval);
532 	} else {
533 		priv->write_urb_interval = port->interrupt_out_urb->interval;
534 		priv->read_urb_interval = port->interrupt_in_urb->interval;
535 		dbg("%s - port %d intervals: read=%d write=%d",
536 		    __func__, port->number,
537 		    priv->read_urb_interval, priv->write_urb_interval);
538 	}
539 	usb_set_serial_port_data(port, priv);
540 
541 	return 0;
542 }
543 
544 
545 static int cypress_earthmate_startup(struct usb_serial *serial)
546 {
547 	struct cypress_private *priv;
548 	struct usb_serial_port *port = serial->port[0];
549 
550 	dbg("%s", __func__);
551 
552 	if (generic_startup(serial)) {
553 		dbg("%s - Failed setting up port %d", __func__,
554 				port->number);
555 		return 1;
556 	}
557 
558 	priv = usb_get_serial_port_data(port);
559 	priv->chiptype = CT_EARTHMATE;
560 	/* All Earthmate devices use the separated-count packet
561 	   format!  Idiotic. */
562 	priv->pkt_fmt = packet_format_1;
563 	if (serial->dev->descriptor.idProduct !=
564 				cpu_to_le16(PRODUCT_ID_EARTHMATEUSB)) {
565 		/* The old original USB Earthmate seemed able to
566 		   handle GET_CONFIG requests; everything they've
567 		   produced since that time crashes if this command is
568 		   attempted :-( */
569 		dbg("%s - Marking this device as unsafe for GET_CONFIG "
570 		    "commands", __func__);
571 		priv->get_cfg_unsafe = !0;
572 	}
573 
574 	return 0;
575 } /* cypress_earthmate_startup */
576 
577 
578 static int cypress_hidcom_startup(struct usb_serial *serial)
579 {
580 	struct cypress_private *priv;
581 
582 	dbg("%s", __func__);
583 
584 	if (generic_startup(serial)) {
585 		dbg("%s - Failed setting up port %d", __func__,
586 				serial->port[0]->number);
587 		return 1;
588 	}
589 
590 	priv = usb_get_serial_port_data(serial->port[0]);
591 	priv->chiptype = CT_CYPHIDCOM;
592 
593 	return 0;
594 } /* cypress_hidcom_startup */
595 
596 
597 static int cypress_ca42v2_startup(struct usb_serial *serial)
598 {
599 	struct cypress_private *priv;
600 
601 	dbg("%s", __func__);
602 
603 	if (generic_startup(serial)) {
604 		dbg("%s - Failed setting up port %d", __func__,
605 				serial->port[0]->number);
606 		return 1;
607 	}
608 
609 	priv = usb_get_serial_port_data(serial->port[0]);
610 	priv->chiptype = CT_CA42V2;
611 
612 	return 0;
613 } /* cypress_ca42v2_startup */
614 
615 
616 static void cypress_shutdown(struct usb_serial *serial)
617 {
618 	struct cypress_private *priv;
619 
620 	dbg("%s - port %d", __func__, serial->port[0]->number);
621 
622 	/* all open ports are closed at this point */
623 
624 	priv = usb_get_serial_port_data(serial->port[0]);
625 
626 	if (priv) {
627 		cypress_buf_free(priv->buf);
628 		kfree(priv);
629 		usb_set_serial_port_data(serial->port[0], NULL);
630 	}
631 }
632 
633 
634 static int cypress_open(struct tty_struct *tty,
635 			struct usb_serial_port *port, struct file *filp)
636 {
637 	struct cypress_private *priv = usb_get_serial_port_data(port);
638 	struct usb_serial *serial = port->serial;
639 	unsigned long flags;
640 	int result = 0;
641 
642 	dbg("%s - port %d", __func__, port->number);
643 
644 	if (!priv->comm_is_ok)
645 		return -EIO;
646 
647 	/* clear halts before open */
648 	usb_clear_halt(serial->dev, 0x81);
649 	usb_clear_halt(serial->dev, 0x02);
650 
651 	spin_lock_irqsave(&priv->lock, flags);
652 	/* reset read/write statistics */
653 	priv->bytes_in = 0;
654 	priv->bytes_out = 0;
655 	priv->cmd_count = 0;
656 	priv->rx_flags = 0;
657 	spin_unlock_irqrestore(&priv->lock, flags);
658 
659 	/* setting to zero could cause data loss */
660 	if (tty)
661 		tty->low_latency = 1;
662 
663 	/* raise both lines and set termios */
664 	spin_lock_irqsave(&priv->lock, flags);
665 	priv->line_control = CONTROL_DTR | CONTROL_RTS;
666 	priv->cmd_ctrl = 1;
667 	spin_unlock_irqrestore(&priv->lock, flags);
668 	result = cypress_write(tty, port, NULL, 0);
669 
670 	if (result) {
671 		dev_err(&port->dev,
672 			"%s - failed setting the control lines - error %d\n",
673 							__func__, result);
674 		return result;
675 	} else
676 		dbg("%s - success setting the control lines", __func__);
677 
678 	if (tty)
679 		cypress_set_termios(tty, port, &priv->tmp_termios);
680 
681 	/* setup the port and start reading from the device */
682 	if (!port->interrupt_in_urb) {
683 		dev_err(&port->dev, "%s - interrupt_in_urb is empty!\n",
684 			__func__);
685 		return -1;
686 	}
687 
688 	usb_fill_int_urb(port->interrupt_in_urb, serial->dev,
689 		usb_rcvintpipe(serial->dev, port->interrupt_in_endpointAddress),
690 		port->interrupt_in_urb->transfer_buffer,
691 		port->interrupt_in_urb->transfer_buffer_length,
692 		cypress_read_int_callback, port, priv->read_urb_interval);
693 	result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
694 
695 	if (result) {
696 		dev_err(&port->dev,
697 			"%s - failed submitting read urb, error %d\n",
698 							__func__, result);
699 		cypress_set_dead(port);
700 	}
701 
702 	return result;
703 } /* cypress_open */
704 
705 
706 static void cypress_close(struct tty_struct *tty,
707 			struct usb_serial_port *port, struct file *filp)
708 {
709 	struct cypress_private *priv = usb_get_serial_port_data(port);
710 	unsigned int c_cflag;
711 	int bps;
712 	long timeout;
713 	wait_queue_t wait;
714 
715 	dbg("%s - port %d", __func__, port->number);
716 
717 	/* wait for data to drain from buffer */
718 	spin_lock_irq(&priv->lock);
719 	timeout = CYPRESS_CLOSING_WAIT;
720 	init_waitqueue_entry(&wait, current);
721 	add_wait_queue(&tty->write_wait, &wait);
722 	for (;;) {
723 		set_current_state(TASK_INTERRUPTIBLE);
724 		if (cypress_buf_data_avail(priv->buf) == 0
725 		|| timeout == 0 || signal_pending(current)
726 		/* without mutex, allowed due to harmless failure mode */
727 		|| port->serial->disconnected)
728 			break;
729 		spin_unlock_irq(&priv->lock);
730 		timeout = schedule_timeout(timeout);
731 		spin_lock_irq(&priv->lock);
732 	}
733 	set_current_state(TASK_RUNNING);
734 	remove_wait_queue(&tty->write_wait, &wait);
735 	/* clear out any remaining data in the buffer */
736 	cypress_buf_clear(priv->buf);
737 	spin_unlock_irq(&priv->lock);
738 
739 	/* writing is potentially harmful, lock must be taken */
740 	mutex_lock(&port->serial->disc_mutex);
741 	if (port->serial->disconnected) {
742 		mutex_unlock(&port->serial->disc_mutex);
743 		return;
744 	}
745 	/* wait for characters to drain from device */
746 	if (tty) {
747 		bps = tty_get_baud_rate(tty);
748 		if (bps > 1200)
749 			timeout = max((HZ * 2560) / bps, HZ / 10);
750 		else
751 			timeout = 2 * HZ;
752 		schedule_timeout_interruptible(timeout);
753 	}
754 
755 	dbg("%s - stopping urbs", __func__);
756 	usb_kill_urb(port->interrupt_in_urb);
757 	usb_kill_urb(port->interrupt_out_urb);
758 
759 	if (tty) {
760 		c_cflag = tty->termios->c_cflag;
761 		if (c_cflag & HUPCL) {
762 			/* drop dtr and rts */
763 			priv = usb_get_serial_port_data(port);
764 			spin_lock_irq(&priv->lock);
765 			priv->line_control = 0;
766 			priv->cmd_ctrl = 1;
767 			spin_unlock_irq(&priv->lock);
768 			cypress_write(tty, port, NULL, 0);
769 		}
770 	}
771 
772 	if (stats)
773 		dev_info(&port->dev, "Statistics: %d Bytes In | %d Bytes Out | %d Commands Issued\n",
774 			priv->bytes_in, priv->bytes_out, priv->cmd_count);
775 	mutex_unlock(&port->serial->disc_mutex);
776 } /* cypress_close */
777 
778 
779 static int cypress_write(struct tty_struct *tty, struct usb_serial_port *port,
780 					const unsigned char *buf, int count)
781 {
782 	struct cypress_private *priv = usb_get_serial_port_data(port);
783 	unsigned long flags;
784 
785 	dbg("%s - port %d, %d bytes", __func__, port->number, count);
786 
787 	/* line control commands, which need to be executed immediately,
788 	   are not put into the buffer for obvious reasons.
789 	 */
790 	if (priv->cmd_ctrl) {
791 		count = 0;
792 		goto finish;
793 	}
794 
795 	if (!count)
796 		return count;
797 
798 	spin_lock_irqsave(&priv->lock, flags);
799 	count = cypress_buf_put(priv->buf, buf, count);
800 	spin_unlock_irqrestore(&priv->lock, flags);
801 
802 finish:
803 	cypress_send(port);
804 
805 	return count;
806 } /* cypress_write */
807 
808 
809 static void cypress_send(struct usb_serial_port *port)
810 {
811 	int count = 0, result, offset, actual_size;
812 	struct cypress_private *priv = usb_get_serial_port_data(port);
813 	unsigned long flags;
814 
815 	if (!priv->comm_is_ok)
816 		return;
817 
818 	dbg("%s - port %d", __func__, port->number);
819 	dbg("%s - interrupt out size is %d", __func__,
820 						port->interrupt_out_size);
821 
822 	spin_lock_irqsave(&priv->lock, flags);
823 	if (priv->write_urb_in_use) {
824 		dbg("%s - can't write, urb in use", __func__);
825 		spin_unlock_irqrestore(&priv->lock, flags);
826 		return;
827 	}
828 	spin_unlock_irqrestore(&priv->lock, flags);
829 
830 	/* clear buffer */
831 	memset(port->interrupt_out_urb->transfer_buffer, 0,
832 						port->interrupt_out_size);
833 
834 	spin_lock_irqsave(&priv->lock, flags);
835 	switch (priv->pkt_fmt) {
836 	default:
837 	case packet_format_1:
838 		/* this is for the CY7C64013... */
839 		offset = 2;
840 		port->interrupt_out_buffer[0] = priv->line_control;
841 		break;
842 	case packet_format_2:
843 		/* this is for the CY7C63743... */
844 		offset = 1;
845 		port->interrupt_out_buffer[0] = priv->line_control;
846 		break;
847 	}
848 
849 	if (priv->line_control & CONTROL_RESET)
850 		priv->line_control &= ~CONTROL_RESET;
851 
852 	if (priv->cmd_ctrl) {
853 		priv->cmd_count++;
854 		dbg("%s - line control command being issued", __func__);
855 		spin_unlock_irqrestore(&priv->lock, flags);
856 		goto send;
857 	} else
858 		spin_unlock_irqrestore(&priv->lock, flags);
859 
860 	count = cypress_buf_get(priv->buf, &port->interrupt_out_buffer[offset],
861 				port->interrupt_out_size-offset);
862 
863 	if (count == 0)
864 		return;
865 
866 	switch (priv->pkt_fmt) {
867 	default:
868 	case packet_format_1:
869 		port->interrupt_out_buffer[1] = count;
870 		break;
871 	case packet_format_2:
872 		port->interrupt_out_buffer[0] |= count;
873 	}
874 
875 	dbg("%s - count is %d", __func__, count);
876 
877 send:
878 	spin_lock_irqsave(&priv->lock, flags);
879 	priv->write_urb_in_use = 1;
880 	spin_unlock_irqrestore(&priv->lock, flags);
881 
882 	if (priv->cmd_ctrl)
883 		actual_size = 1;
884 	else
885 		actual_size = count +
886 			      (priv->pkt_fmt == packet_format_1 ? 2 : 1);
887 
888 	usb_serial_debug_data(debug, &port->dev, __func__,
889 		port->interrupt_out_size,
890 		port->interrupt_out_urb->transfer_buffer);
891 
892 	usb_fill_int_urb(port->interrupt_out_urb, port->serial->dev,
893 		usb_sndintpipe(port->serial->dev, port->interrupt_out_endpointAddress),
894 		port->interrupt_out_buffer, port->interrupt_out_size,
895 		cypress_write_int_callback, port, priv->write_urb_interval);
896 	result = usb_submit_urb(port->interrupt_out_urb, GFP_ATOMIC);
897 	if (result) {
898 		dev_err(&port->dev,
899 				"%s - failed submitting write urb, error %d\n",
900 							__func__, result);
901 		priv->write_urb_in_use = 0;
902 		cypress_set_dead(port);
903 	}
904 
905 	spin_lock_irqsave(&priv->lock, flags);
906 	if (priv->cmd_ctrl)
907 		priv->cmd_ctrl = 0;
908 
909 	/* do not count the line control and size bytes */
910 	priv->bytes_out += count;
911 	spin_unlock_irqrestore(&priv->lock, flags);
912 
913 	usb_serial_port_softint(port);
914 } /* cypress_send */
915 
916 
917 /* returns how much space is available in the soft buffer */
918 static int cypress_write_room(struct tty_struct *tty)
919 {
920 	struct usb_serial_port *port = tty->driver_data;
921 	struct cypress_private *priv = usb_get_serial_port_data(port);
922 	int room = 0;
923 	unsigned long flags;
924 
925 	dbg("%s - port %d", __func__, port->number);
926 
927 	spin_lock_irqsave(&priv->lock, flags);
928 	room = cypress_buf_space_avail(priv->buf);
929 	spin_unlock_irqrestore(&priv->lock, flags);
930 
931 	dbg("%s - returns %d", __func__, room);
932 	return room;
933 }
934 
935 
936 static int cypress_tiocmget(struct tty_struct *tty, struct file *file)
937 {
938 	struct usb_serial_port *port = tty->driver_data;
939 	struct cypress_private *priv = usb_get_serial_port_data(port);
940 	__u8 status, control;
941 	unsigned int result = 0;
942 	unsigned long flags;
943 
944 	dbg("%s - port %d", __func__, port->number);
945 
946 	spin_lock_irqsave(&priv->lock, flags);
947 	control = priv->line_control;
948 	status = priv->current_status;
949 	spin_unlock_irqrestore(&priv->lock, flags);
950 
951 	result = ((control & CONTROL_DTR)        ? TIOCM_DTR : 0)
952 		| ((control & CONTROL_RTS)       ? TIOCM_RTS : 0)
953 		| ((status & UART_CTS)        ? TIOCM_CTS : 0)
954 		| ((status & UART_DSR)        ? TIOCM_DSR : 0)
955 		| ((status & UART_RI)         ? TIOCM_RI  : 0)
956 		| ((status & UART_CD)         ? TIOCM_CD  : 0);
957 
958 	dbg("%s - result = %x", __func__, result);
959 
960 	return result;
961 }
962 
963 
964 static int cypress_tiocmset(struct tty_struct *tty, struct file *file,
965 			       unsigned int set, unsigned int clear)
966 {
967 	struct usb_serial_port *port = tty->driver_data;
968 	struct cypress_private *priv = usb_get_serial_port_data(port);
969 	unsigned long flags;
970 
971 	dbg("%s - port %d", __func__, port->number);
972 
973 	spin_lock_irqsave(&priv->lock, flags);
974 	if (set & TIOCM_RTS)
975 		priv->line_control |= CONTROL_RTS;
976 	if (set & TIOCM_DTR)
977 		priv->line_control |= CONTROL_DTR;
978 	if (clear & TIOCM_RTS)
979 		priv->line_control &= ~CONTROL_RTS;
980 	if (clear & TIOCM_DTR)
981 		priv->line_control &= ~CONTROL_DTR;
982 	priv->cmd_ctrl = 1;
983 	spin_unlock_irqrestore(&priv->lock, flags);
984 
985 	return cypress_write(tty, port, NULL, 0);
986 }
987 
988 
989 static int cypress_ioctl(struct tty_struct *tty, struct file *file,
990 					unsigned int cmd, unsigned long arg)
991 {
992 	struct usb_serial_port *port = tty->driver_data;
993 	struct cypress_private *priv = usb_get_serial_port_data(port);
994 
995 	dbg("%s - port %d, cmd 0x%.4x", __func__, port->number, cmd);
996 
997 	switch (cmd) {
998 	/* This code comes from drivers/char/serial.c and ftdi_sio.c */
999 	case TIOCMIWAIT:
1000 		while (priv != NULL) {
1001 			interruptible_sleep_on(&priv->delta_msr_wait);
1002 			/* see if a signal did it */
1003 			if (signal_pending(current))
1004 				return -ERESTARTSYS;
1005 			else {
1006 				char diff = priv->diff_status;
1007 				if (diff == 0)
1008 					return -EIO; /* no change => error */
1009 
1010 				/* consume all events */
1011 				priv->diff_status = 0;
1012 
1013 				/* return 0 if caller wanted to know about
1014 				   these bits */
1015 				if (((arg & TIOCM_RNG) && (diff & UART_RI)) ||
1016 				    ((arg & TIOCM_DSR) && (diff & UART_DSR)) ||
1017 				    ((arg & TIOCM_CD) && (diff & UART_CD)) ||
1018 				    ((arg & TIOCM_CTS) && (diff & UART_CTS)))
1019 					return 0;
1020 				/* otherwise caller can't care less about what
1021 				 * happened, and so we continue to wait for
1022 				 * more events.
1023 				 */
1024 			}
1025 		}
1026 		return 0;
1027 	default:
1028 		break;
1029 	}
1030 	dbg("%s - arg not supported - it was 0x%04x - check include/asm/ioctls.h", __func__, cmd);
1031 	return -ENOIOCTLCMD;
1032 } /* cypress_ioctl */
1033 
1034 
1035 static void cypress_set_termios(struct tty_struct *tty,
1036 	struct usb_serial_port *port, struct ktermios *old_termios)
1037 {
1038 	struct cypress_private *priv = usb_get_serial_port_data(port);
1039 	int data_bits, stop_bits, parity_type, parity_enable;
1040 	unsigned cflag, iflag;
1041 	unsigned long flags;
1042 	__u8 oldlines;
1043 	int linechange = 0;
1044 
1045 	dbg("%s - port %d", __func__, port->number);
1046 
1047 	spin_lock_irqsave(&priv->lock, flags);
1048 	if (!priv->termios_initialized) {
1049 		if (priv->chiptype == CT_EARTHMATE) {
1050 			*(tty->termios) = tty_std_termios;
1051 			tty->termios->c_cflag = B4800 | CS8 | CREAD | HUPCL |
1052 				CLOCAL;
1053 			tty->termios->c_ispeed = 4800;
1054 			tty->termios->c_ospeed = 4800;
1055 		} else if (priv->chiptype == CT_CYPHIDCOM) {
1056 			*(tty->termios) = tty_std_termios;
1057 			tty->termios->c_cflag = B9600 | CS8 | CREAD | HUPCL |
1058 				CLOCAL;
1059 			tty->termios->c_ispeed = 9600;
1060 			tty->termios->c_ospeed = 9600;
1061 		} else if (priv->chiptype == CT_CA42V2) {
1062 			*(tty->termios) = tty_std_termios;
1063 			tty->termios->c_cflag = B9600 | CS8 | CREAD | HUPCL |
1064 				CLOCAL;
1065 			tty->termios->c_ispeed = 9600;
1066 			tty->termios->c_ospeed = 9600;
1067 		}
1068 		priv->termios_initialized = 1;
1069 	}
1070 	spin_unlock_irqrestore(&priv->lock, flags);
1071 
1072 	/* Unsupported features need clearing */
1073 	tty->termios->c_cflag &= ~(CMSPAR|CRTSCTS);
1074 
1075 	cflag = tty->termios->c_cflag;
1076 	iflag = tty->termios->c_iflag;
1077 
1078 	/* check if there are new settings */
1079 	if (old_termios) {
1080 		spin_lock_irqsave(&priv->lock, flags);
1081 		priv->tmp_termios = *(tty->termios);
1082 		spin_unlock_irqrestore(&priv->lock, flags);
1083 	}
1084 
1085 	/* set number of data bits, parity, stop bits */
1086 	/* when parity is disabled the parity type bit is ignored */
1087 
1088 	/* 1 means 2 stop bits, 0 means 1 stop bit */
1089 	stop_bits = cflag & CSTOPB ? 1 : 0;
1090 
1091 	if (cflag & PARENB) {
1092 		parity_enable = 1;
1093 		/* 1 means odd parity, 0 means even parity */
1094 		parity_type = cflag & PARODD ? 1 : 0;
1095 	} else
1096 		parity_enable = parity_type = 0;
1097 
1098 	switch (cflag & CSIZE) {
1099 	case CS5:
1100 		data_bits = 0;
1101 		break;
1102 	case CS6:
1103 		data_bits = 1;
1104 		break;
1105 	case CS7:
1106 		data_bits = 2;
1107 		break;
1108 	case CS8:
1109 		data_bits = 3;
1110 		break;
1111 	default:
1112 		dev_err(&port->dev, "%s - CSIZE was set, but not CS5-CS8\n",
1113 			__func__);
1114 		data_bits = 3;
1115 	}
1116 	spin_lock_irqsave(&priv->lock, flags);
1117 	oldlines = priv->line_control;
1118 	if ((cflag & CBAUD) == B0) {
1119 		/* drop dtr and rts */
1120 		dbg("%s - dropping the lines, baud rate 0bps", __func__);
1121 		priv->line_control &= ~(CONTROL_DTR | CONTROL_RTS);
1122 	} else
1123 		priv->line_control = (CONTROL_DTR | CONTROL_RTS);
1124 	spin_unlock_irqrestore(&priv->lock, flags);
1125 
1126 	dbg("%s - sending %d stop_bits, %d parity_enable, %d parity_type, "
1127 			"%d data_bits (+5)", __func__, stop_bits,
1128 			parity_enable, parity_type, data_bits);
1129 
1130 	cypress_serial_control(tty, port, tty_get_baud_rate(tty),
1131 			data_bits, stop_bits,
1132 			parity_enable, parity_type,
1133 			0, CYPRESS_SET_CONFIG);
1134 
1135 	/* we perform a CYPRESS_GET_CONFIG so that the current settings are
1136 	 * filled into the private structure this should confirm that all is
1137 	 * working if it returns what we just set */
1138 	cypress_serial_control(tty, port, 0, 0, 0, 0, 0, 0, CYPRESS_GET_CONFIG);
1139 
1140 	/* Here we can define custom tty settings for devices; the main tty
1141 	 * termios flag base comes from empeg.c */
1142 
1143 	spin_lock_irqsave(&priv->lock, flags);
1144 	if (priv->chiptype == CT_EARTHMATE && priv->baud_rate == 4800) {
1145 		dbg("Using custom termios settings for a baud rate of "
1146 				"4800bps.");
1147 		/* define custom termios settings for NMEA protocol */
1148 
1149 		tty->termios->c_iflag /* input modes - */
1150 			&= ~(IGNBRK  /* disable ignore break */
1151 			| BRKINT     /* disable break causes interrupt */
1152 			| PARMRK     /* disable mark parity errors */
1153 			| ISTRIP     /* disable clear high bit of input char */
1154 			| INLCR      /* disable translate NL to CR */
1155 			| IGNCR      /* disable ignore CR */
1156 			| ICRNL      /* disable translate CR to NL */
1157 			| IXON);     /* disable enable XON/XOFF flow control */
1158 
1159 		tty->termios->c_oflag /* output modes */
1160 			&= ~OPOST;    /* disable postprocess output char */
1161 
1162 		tty->termios->c_lflag /* line discipline modes */
1163 			&= ~(ECHO     /* disable echo input characters */
1164 			| ECHONL      /* disable echo new line */
1165 			| ICANON      /* disable erase, kill, werase, and rprnt
1166 					 special characters */
1167 			| ISIG        /* disable interrupt, quit, and suspend
1168 					 special characters */
1169 			| IEXTEN);    /* disable non-POSIX special characters */
1170 	} /* CT_CYPHIDCOM: Application should handle this for device */
1171 
1172 	linechange = (priv->line_control != oldlines);
1173 	spin_unlock_irqrestore(&priv->lock, flags);
1174 
1175 	/* if necessary, set lines */
1176 	if (linechange) {
1177 		priv->cmd_ctrl = 1;
1178 		cypress_write(tty, port, NULL, 0);
1179 	}
1180 } /* cypress_set_termios */
1181 
1182 
1183 /* returns amount of data still left in soft buffer */
1184 static int cypress_chars_in_buffer(struct tty_struct *tty)
1185 {
1186 	struct usb_serial_port *port = tty->driver_data;
1187 	struct cypress_private *priv = usb_get_serial_port_data(port);
1188 	int chars = 0;
1189 	unsigned long flags;
1190 
1191 	dbg("%s - port %d", __func__, port->number);
1192 
1193 	spin_lock_irqsave(&priv->lock, flags);
1194 	chars = cypress_buf_data_avail(priv->buf);
1195 	spin_unlock_irqrestore(&priv->lock, flags);
1196 
1197 	dbg("%s - returns %d", __func__, chars);
1198 	return chars;
1199 }
1200 
1201 
1202 static void cypress_throttle(struct tty_struct *tty)
1203 {
1204 	struct usb_serial_port *port = tty->driver_data;
1205 	struct cypress_private *priv = usb_get_serial_port_data(port);
1206 	unsigned long flags;
1207 
1208 	dbg("%s - port %d", __func__, port->number);
1209 
1210 	spin_lock_irqsave(&priv->lock, flags);
1211 	priv->rx_flags = THROTTLED;
1212 	spin_unlock_irqrestore(&priv->lock, flags);
1213 }
1214 
1215 
1216 static void cypress_unthrottle(struct tty_struct *tty)
1217 {
1218 	struct usb_serial_port *port = tty->driver_data;
1219 	struct cypress_private *priv = usb_get_serial_port_data(port);
1220 	int actually_throttled, result;
1221 	unsigned long flags;
1222 
1223 	dbg("%s - port %d", __func__, port->number);
1224 
1225 	spin_lock_irqsave(&priv->lock, flags);
1226 	actually_throttled = priv->rx_flags & ACTUALLY_THROTTLED;
1227 	priv->rx_flags = 0;
1228 	spin_unlock_irqrestore(&priv->lock, flags);
1229 
1230 	if (!priv->comm_is_ok)
1231 		return;
1232 
1233 	if (actually_throttled) {
1234 		port->interrupt_in_urb->dev = port->serial->dev;
1235 
1236 		result = usb_submit_urb(port->interrupt_in_urb, GFP_ATOMIC);
1237 		if (result) {
1238 			dev_err(&port->dev, "%s - failed submitting read urb, "
1239 					"error %d\n", __func__, result);
1240 			cypress_set_dead(port);
1241 		}
1242 	}
1243 }
1244 
1245 
1246 static void cypress_read_int_callback(struct urb *urb)
1247 {
1248 	struct usb_serial_port *port = urb->context;
1249 	struct cypress_private *priv = usb_get_serial_port_data(port);
1250 	struct tty_struct *tty;
1251 	unsigned char *data = urb->transfer_buffer;
1252 	unsigned long flags;
1253 	char tty_flag = TTY_NORMAL;
1254 	int havedata = 0;
1255 	int bytes = 0;
1256 	int result;
1257 	int i = 0;
1258 	int status = urb->status;
1259 
1260 	dbg("%s - port %d", __func__, port->number);
1261 
1262 	switch (status) {
1263 	case 0: /* success */
1264 		break;
1265 	case -ECONNRESET:
1266 	case -ENOENT:
1267 	case -ESHUTDOWN:
1268 		/* precursor to disconnect so just go away */
1269 		return;
1270 	case -EPIPE:
1271 		usb_clear_halt(port->serial->dev, 0x81);
1272 		break;
1273 	default:
1274 		/* something ugly is going on... */
1275 		dev_err(&urb->dev->dev,
1276 			"%s - unexpected nonzero read status received: %d\n",
1277 							__func__, status);
1278 		cypress_set_dead(port);
1279 		return;
1280 	}
1281 
1282 	spin_lock_irqsave(&priv->lock, flags);
1283 	if (priv->rx_flags & THROTTLED) {
1284 		dbg("%s - now throttling", __func__);
1285 		priv->rx_flags |= ACTUALLY_THROTTLED;
1286 		spin_unlock_irqrestore(&priv->lock, flags);
1287 		return;
1288 	}
1289 	spin_unlock_irqrestore(&priv->lock, flags);
1290 
1291 	tty = tty_port_tty_get(&port->port);
1292 	if (!tty) {
1293 		dbg("%s - bad tty pointer - exiting", __func__);
1294 		return;
1295 	}
1296 
1297 	spin_lock_irqsave(&priv->lock, flags);
1298 	result = urb->actual_length;
1299 	switch (priv->pkt_fmt) {
1300 	default:
1301 	case packet_format_1:
1302 		/* This is for the CY7C64013... */
1303 		priv->current_status = data[0] & 0xF8;
1304 		bytes = data[1] + 2;
1305 		i = 2;
1306 		if (bytes > 2)
1307 			havedata = 1;
1308 		break;
1309 	case packet_format_2:
1310 		/* This is for the CY7C63743... */
1311 		priv->current_status = data[0] & 0xF8;
1312 		bytes = (data[0] & 0x07) + 1;
1313 		i = 1;
1314 		if (bytes > 1)
1315 			havedata = 1;
1316 		break;
1317 	}
1318 	spin_unlock_irqrestore(&priv->lock, flags);
1319 	if (result < bytes) {
1320 		dbg("%s - wrong packet size - received %d bytes but packet "
1321 		    "said %d bytes", __func__, result, bytes);
1322 		goto continue_read;
1323 	}
1324 
1325 	usb_serial_debug_data(debug, &port->dev, __func__,
1326 						urb->actual_length, data);
1327 
1328 	spin_lock_irqsave(&priv->lock, flags);
1329 	/* check to see if status has changed */
1330 	if (priv->current_status != priv->prev_status) {
1331 		priv->diff_status |= priv->current_status ^
1332 			priv->prev_status;
1333 		wake_up_interruptible(&priv->delta_msr_wait);
1334 		priv->prev_status = priv->current_status;
1335 	}
1336 	spin_unlock_irqrestore(&priv->lock, flags);
1337 
1338 	/* hangup, as defined in acm.c... this might be a bad place for it
1339 	 * though */
1340 	if (tty && !(tty->termios->c_cflag & CLOCAL) &&
1341 			!(priv->current_status & UART_CD)) {
1342 		dbg("%s - calling hangup", __func__);
1343 		tty_hangup(tty);
1344 		goto continue_read;
1345 	}
1346 
1347 	/* There is one error bit... I'm assuming it is a parity error
1348 	 * indicator as the generic firmware will set this bit to 1 if a
1349 	 * parity error occurs.
1350 	 * I can not find reference to any other error events. */
1351 	spin_lock_irqsave(&priv->lock, flags);
1352 	if (priv->current_status & CYP_ERROR) {
1353 		spin_unlock_irqrestore(&priv->lock, flags);
1354 		tty_flag = TTY_PARITY;
1355 		dbg("%s - Parity Error detected", __func__);
1356 	} else
1357 		spin_unlock_irqrestore(&priv->lock, flags);
1358 
1359 	/* process read if there is data other than line status */
1360 	if (tty && (bytes > i)) {
1361 		bytes = tty_buffer_request_room(tty, bytes);
1362 		for (; i < bytes ; ++i) {
1363 			dbg("pushing byte number %d - %d - %c", i, data[i],
1364 					data[i]);
1365 			tty_insert_flip_char(tty, data[i], tty_flag);
1366 		}
1367 		tty_flip_buffer_push(tty);
1368 	}
1369 
1370 	spin_lock_irqsave(&priv->lock, flags);
1371 	/* control and status byte(s) are also counted */
1372 	priv->bytes_in += bytes;
1373 	spin_unlock_irqrestore(&priv->lock, flags);
1374 
1375 continue_read:
1376 	tty_kref_put(tty);
1377 
1378 	/* Continue trying to always read... unless the port has closed. */
1379 
1380 	if (port->port.count > 0 && priv->comm_is_ok) {
1381 		usb_fill_int_urb(port->interrupt_in_urb, port->serial->dev,
1382 				usb_rcvintpipe(port->serial->dev,
1383 					port->interrupt_in_endpointAddress),
1384 				port->interrupt_in_urb->transfer_buffer,
1385 				port->interrupt_in_urb->transfer_buffer_length,
1386 				cypress_read_int_callback, port,
1387 				priv->read_urb_interval);
1388 		result = usb_submit_urb(port->interrupt_in_urb, GFP_ATOMIC);
1389 		if (result) {
1390 			dev_err(&urb->dev->dev, "%s - failed resubmitting "
1391 					"read urb, error %d\n", __func__,
1392 					result);
1393 			cypress_set_dead(port);
1394 		}
1395 	}
1396 
1397 	return;
1398 } /* cypress_read_int_callback */
1399 
1400 
1401 static void cypress_write_int_callback(struct urb *urb)
1402 {
1403 	struct usb_serial_port *port = urb->context;
1404 	struct cypress_private *priv = usb_get_serial_port_data(port);
1405 	int result;
1406 	int status = urb->status;
1407 
1408 	dbg("%s - port %d", __func__, port->number);
1409 
1410 	switch (status) {
1411 	case 0:
1412 		/* success */
1413 		break;
1414 	case -ECONNRESET:
1415 	case -ENOENT:
1416 	case -ESHUTDOWN:
1417 		/* this urb is terminated, clean up */
1418 		dbg("%s - urb shutting down with status: %d",
1419 						__func__, status);
1420 		priv->write_urb_in_use = 0;
1421 		return;
1422 	case -EPIPE: /* no break needed; clear halt and resubmit */
1423 		if (!priv->comm_is_ok)
1424 			break;
1425 		usb_clear_halt(port->serial->dev, 0x02);
1426 		/* error in the urb, so we have to resubmit it */
1427 		dbg("%s - nonzero write bulk status received: %d",
1428 			__func__, status);
1429 		port->interrupt_out_urb->transfer_buffer_length = 1;
1430 		port->interrupt_out_urb->dev = port->serial->dev;
1431 		result = usb_submit_urb(port->interrupt_out_urb, GFP_ATOMIC);
1432 		if (!result)
1433 			return;
1434 		dev_err(&urb->dev->dev,
1435 			"%s - failed resubmitting write urb, error %d\n",
1436 							__func__, result);
1437 		cypress_set_dead(port);
1438 		break;
1439 	default:
1440 		dev_err(&urb->dev->dev,
1441 			 "%s - unexpected nonzero write status received: %d\n",
1442 							__func__, status);
1443 		cypress_set_dead(port);
1444 		break;
1445 	}
1446 	priv->write_urb_in_use = 0;
1447 
1448 	/* send any buffered data */
1449 	cypress_send(port);
1450 }
1451 
1452 
1453 /*****************************************************************************
1454  * Write buffer functions - buffering code from pl2303 used
1455  *****************************************************************************/
1456 
1457 /*
1458  * cypress_buf_alloc
1459  *
1460  * Allocate a circular buffer and all associated memory.
1461  */
1462 
1463 static struct cypress_buf *cypress_buf_alloc(unsigned int size)
1464 {
1465 
1466 	struct cypress_buf *cb;
1467 
1468 
1469 	if (size == 0)
1470 		return NULL;
1471 
1472 	cb = kmalloc(sizeof(struct cypress_buf), GFP_KERNEL);
1473 	if (cb == NULL)
1474 		return NULL;
1475 
1476 	cb->buf_buf = kmalloc(size, GFP_KERNEL);
1477 	if (cb->buf_buf == NULL) {
1478 		kfree(cb);
1479 		return NULL;
1480 	}
1481 
1482 	cb->buf_size = size;
1483 	cb->buf_get = cb->buf_put = cb->buf_buf;
1484 
1485 	return cb;
1486 
1487 }
1488 
1489 
1490 /*
1491  * cypress_buf_free
1492  *
1493  * Free the buffer and all associated memory.
1494  */
1495 
1496 static void cypress_buf_free(struct cypress_buf *cb)
1497 {
1498 	if (cb) {
1499 		kfree(cb->buf_buf);
1500 		kfree(cb);
1501 	}
1502 }
1503 
1504 
1505 /*
1506  * cypress_buf_clear
1507  *
1508  * Clear out all data in the circular buffer.
1509  */
1510 
1511 static void cypress_buf_clear(struct cypress_buf *cb)
1512 {
1513 	if (cb != NULL)
1514 		cb->buf_get = cb->buf_put;
1515 		/* equivalent to a get of all data available */
1516 }
1517 
1518 
1519 /*
1520  * cypress_buf_data_avail
1521  *
1522  * Return the number of bytes of data available in the circular
1523  * buffer.
1524  */
1525 
1526 static unsigned int cypress_buf_data_avail(struct cypress_buf *cb)
1527 {
1528 	if (cb != NULL)
1529 		return (cb->buf_size + cb->buf_put - cb->buf_get)
1530 							% cb->buf_size;
1531 	else
1532 		return 0;
1533 }
1534 
1535 
1536 /*
1537  * cypress_buf_space_avail
1538  *
1539  * Return the number of bytes of space available in the circular
1540  * buffer.
1541  */
1542 
1543 static unsigned int cypress_buf_space_avail(struct cypress_buf *cb)
1544 {
1545 	if (cb != NULL)
1546 		return (cb->buf_size + cb->buf_get - cb->buf_put - 1)
1547 							% cb->buf_size;
1548 	else
1549 		return 0;
1550 }
1551 
1552 
1553 /*
1554  * cypress_buf_put
1555  *
1556  * Copy data data from a user buffer and put it into the circular buffer.
1557  * Restrict to the amount of space available.
1558  *
1559  * Return the number of bytes copied.
1560  */
1561 
1562 static unsigned int cypress_buf_put(struct cypress_buf *cb, const char *buf,
1563 	unsigned int count)
1564 {
1565 
1566 	unsigned int len;
1567 
1568 
1569 	if (cb == NULL)
1570 		return 0;
1571 
1572 	len  = cypress_buf_space_avail(cb);
1573 	if (count > len)
1574 		count = len;
1575 
1576 	if (count == 0)
1577 		return 0;
1578 
1579 	len = cb->buf_buf + cb->buf_size - cb->buf_put;
1580 	if (count > len) {
1581 		memcpy(cb->buf_put, buf, len);
1582 		memcpy(cb->buf_buf, buf+len, count - len);
1583 		cb->buf_put = cb->buf_buf + count - len;
1584 	} else {
1585 		memcpy(cb->buf_put, buf, count);
1586 		if (count < len)
1587 			cb->buf_put += count;
1588 		else /* count == len */
1589 			cb->buf_put = cb->buf_buf;
1590 	}
1591 
1592 	return count;
1593 
1594 }
1595 
1596 
1597 /*
1598  * cypress_buf_get
1599  *
1600  * Get data from the circular buffer and copy to the given buffer.
1601  * Restrict to the amount of data available.
1602  *
1603  * Return the number of bytes copied.
1604  */
1605 
1606 static unsigned int cypress_buf_get(struct cypress_buf *cb, char *buf,
1607 	unsigned int count)
1608 {
1609 
1610 	unsigned int len;
1611 
1612 
1613 	if (cb == NULL)
1614 		return 0;
1615 
1616 	len = cypress_buf_data_avail(cb);
1617 	if (count > len)
1618 		count = len;
1619 
1620 	if (count == 0)
1621 		return 0;
1622 
1623 	len = cb->buf_buf + cb->buf_size - cb->buf_get;
1624 	if (count > len) {
1625 		memcpy(buf, cb->buf_get, len);
1626 		memcpy(buf+len, cb->buf_buf, count - len);
1627 		cb->buf_get = cb->buf_buf + count - len;
1628 	} else {
1629 		memcpy(buf, cb->buf_get, count);
1630 		if (count < len)
1631 			cb->buf_get += count;
1632 		else /* count == len */
1633 			cb->buf_get = cb->buf_buf;
1634 	}
1635 
1636 	return count;
1637 
1638 }
1639 
1640 /*****************************************************************************
1641  * Module functions
1642  *****************************************************************************/
1643 
1644 static int __init cypress_init(void)
1645 {
1646 	int retval;
1647 
1648 	dbg("%s", __func__);
1649 
1650 	retval = usb_serial_register(&cypress_earthmate_device);
1651 	if (retval)
1652 		goto failed_em_register;
1653 	retval = usb_serial_register(&cypress_hidcom_device);
1654 	if (retval)
1655 		goto failed_hidcom_register;
1656 	retval = usb_serial_register(&cypress_ca42v2_device);
1657 	if (retval)
1658 		goto failed_ca42v2_register;
1659 	retval = usb_register(&cypress_driver);
1660 	if (retval)
1661 		goto failed_usb_register;
1662 
1663 	printk(KERN_INFO KBUILD_MODNAME ": " DRIVER_VERSION ":"
1664 	       DRIVER_DESC "\n");
1665 	return 0;
1666 
1667 failed_usb_register:
1668 	usb_serial_deregister(&cypress_ca42v2_device);
1669 failed_ca42v2_register:
1670 	usb_serial_deregister(&cypress_hidcom_device);
1671 failed_hidcom_register:
1672 	usb_serial_deregister(&cypress_earthmate_device);
1673 failed_em_register:
1674 	return retval;
1675 }
1676 
1677 
1678 static void __exit cypress_exit(void)
1679 {
1680 	dbg("%s", __func__);
1681 
1682 	usb_deregister(&cypress_driver);
1683 	usb_serial_deregister(&cypress_earthmate_device);
1684 	usb_serial_deregister(&cypress_hidcom_device);
1685 	usb_serial_deregister(&cypress_ca42v2_device);
1686 }
1687 
1688 
1689 module_init(cypress_init);
1690 module_exit(cypress_exit);
1691 
1692 MODULE_AUTHOR(DRIVER_AUTHOR);
1693 MODULE_DESCRIPTION(DRIVER_DESC);
1694 MODULE_VERSION(DRIVER_VERSION);
1695 MODULE_LICENSE("GPL");
1696 
1697 module_param(debug, bool, S_IRUGO | S_IWUSR);
1698 MODULE_PARM_DESC(debug, "Debug enabled or not");
1699 module_param(stats, bool, S_IRUGO | S_IWUSR);
1700 MODULE_PARM_DESC(stats, "Enable statistics or not");
1701 module_param(interval, int, S_IRUGO | S_IWUSR);
1702 MODULE_PARM_DESC(interval, "Overrides interrupt interval");
1703