xref: /linux/drivers/usb/serial/cypress_m8.c (revision 2277ab4a1df50e05bc732fe9488d4e902bb8399a)
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_release(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 usb_serial_port *port);
178 static void cypress_dtr_rts(struct usb_serial_port *port, int on);
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 	.release =			cypress_release,
219 	.open =				cypress_open,
220 	.close =			cypress_close,
221 	.dtr_rts =			cypress_dtr_rts,
222 	.write =			cypress_write,
223 	.write_room =			cypress_write_room,
224 	.ioctl =			cypress_ioctl,
225 	.set_termios =			cypress_set_termios,
226 	.tiocmget =			cypress_tiocmget,
227 	.tiocmset =			cypress_tiocmset,
228 	.chars_in_buffer =		cypress_chars_in_buffer,
229 	.throttle =		 	cypress_throttle,
230 	.unthrottle =			cypress_unthrottle,
231 	.read_int_callback =		cypress_read_int_callback,
232 	.write_int_callback =		cypress_write_int_callback,
233 };
234 
235 static struct usb_serial_driver cypress_hidcom_device = {
236 	.driver = {
237 		.owner =		THIS_MODULE,
238 		.name =			"cyphidcom",
239 	},
240 	.description =			"HID->COM RS232 Adapter",
241 	.usb_driver = 			&cypress_driver,
242 	.id_table =			id_table_cyphidcomrs232,
243 	.num_ports =			1,
244 	.attach =			cypress_hidcom_startup,
245 	.release =			cypress_release,
246 	.open =				cypress_open,
247 	.close =			cypress_close,
248 	.dtr_rts =			cypress_dtr_rts,
249 	.write =			cypress_write,
250 	.write_room =			cypress_write_room,
251 	.ioctl =			cypress_ioctl,
252 	.set_termios =			cypress_set_termios,
253 	.tiocmget =			cypress_tiocmget,
254 	.tiocmset =			cypress_tiocmset,
255 	.chars_in_buffer =		cypress_chars_in_buffer,
256 	.throttle =			cypress_throttle,
257 	.unthrottle =			cypress_unthrottle,
258 	.read_int_callback =		cypress_read_int_callback,
259 	.write_int_callback =		cypress_write_int_callback,
260 };
261 
262 static struct usb_serial_driver cypress_ca42v2_device = {
263 	.driver = {
264 		.owner =		THIS_MODULE,
265 		.name =			"nokiaca42v2",
266 	},
267 	.description =			"Nokia CA-42 V2 Adapter",
268 	.usb_driver = 			&cypress_driver,
269 	.id_table =			id_table_nokiaca42v2,
270 	.num_ports =			1,
271 	.attach =			cypress_ca42v2_startup,
272 	.release =			cypress_release,
273 	.open =				cypress_open,
274 	.close =			cypress_close,
275 	.dtr_rts =			cypress_dtr_rts,
276 	.write =			cypress_write,
277 	.write_room =			cypress_write_room,
278 	.ioctl =			cypress_ioctl,
279 	.set_termios =			cypress_set_termios,
280 	.tiocmget =			cypress_tiocmget,
281 	.tiocmset =			cypress_tiocmset,
282 	.chars_in_buffer =		cypress_chars_in_buffer,
283 	.throttle =			cypress_throttle,
284 	.unthrottle =			cypress_unthrottle,
285 	.read_int_callback =		cypress_read_int_callback,
286 	.write_int_callback =		cypress_write_int_callback,
287 };
288 
289 /*****************************************************************************
290  * Cypress serial helper functions
291  *****************************************************************************/
292 
293 
294 static int analyze_baud_rate(struct usb_serial_port *port, speed_t new_rate)
295 {
296 	struct cypress_private *priv;
297 	priv = usb_get_serial_port_data(port);
298 
299 	/*
300 	 * The general purpose firmware for the Cypress M8 allows for
301 	 * a maximum speed of 57600bps (I have no idea whether DeLorme
302 	 * chose to use the general purpose firmware or not), if you
303 	 * need to modify this speed setting for your own project
304 	 * please add your own chiptype and modify the code likewise.
305 	 * The Cypress HID->COM device will work successfully up to
306 	 * 115200bps (but the actual throughput is around 3kBps).
307 	 */
308 	if (port->serial->dev->speed == USB_SPEED_LOW) {
309 		/*
310 		 * Mike Isely <isely@pobox.com> 2-Feb-2008: The
311 		 * Cypress app note that describes this mechanism
312 		 * states the the low-speed part can't handle more
313 		 * than 800 bytes/sec, in which case 4800 baud is the
314 		 * safest speed for a part like that.
315 		 */
316 		if (new_rate > 4800) {
317 			dbg("%s - failed setting baud rate, device incapable "
318 			    "speed %d", __func__, new_rate);
319 			return -1;
320 		}
321 	}
322 	switch (priv->chiptype) {
323 	case CT_EARTHMATE:
324 		if (new_rate <= 600) {
325 			/* 300 and 600 baud rates are supported under
326 			 * the generic firmware, but are not used with
327 			 * NMEA and SiRF protocols */
328 			dbg("%s - failed setting baud rate, unsupported speed "
329 			    "of %d on Earthmate GPS", __func__, new_rate);
330 			return -1;
331 		}
332 		break;
333 	default:
334 		break;
335 	}
336 	return new_rate;
337 }
338 
339 
340 /* This function can either set or retrieve the current serial line settings */
341 static int cypress_serial_control(struct tty_struct *tty,
342 	struct usb_serial_port *port, speed_t baud_rate, int data_bits,
343 	int stop_bits, int parity_enable, int parity_type, int reset,
344 	int cypress_request_type)
345 {
346 	int new_baudrate = 0, retval = 0, tries = 0;
347 	struct cypress_private *priv;
348 	__u8 feature_buffer[5];
349 	unsigned long flags;
350 
351 	dbg("%s", __func__);
352 
353 	priv = usb_get_serial_port_data(port);
354 
355 	if (!priv->comm_is_ok)
356 		return -ENODEV;
357 
358 	switch (cypress_request_type) {
359 	case CYPRESS_SET_CONFIG:
360 		new_baudrate = priv->baud_rate;
361 		/* 0 means 'Hang up' so doesn't change the true bit rate */
362 		if (baud_rate == 0)
363 			new_baudrate = priv->baud_rate;
364 		/* Change of speed ? */
365 		else if (baud_rate != priv->baud_rate) {
366 			dbg("%s - baud rate is changing", __func__);
367 			retval = analyze_baud_rate(port, baud_rate);
368 			if (retval >=  0) {
369 				new_baudrate = retval;
370 				dbg("%s - New baud rate set to %d",
371 				    __func__, new_baudrate);
372 			}
373 		}
374 		dbg("%s - baud rate is being sent as %d",
375 					__func__, new_baudrate);
376 
377 		memset(feature_buffer, 0, sizeof(feature_buffer));
378 		/* fill the feature_buffer with new configuration */
379 		*((u_int32_t *)feature_buffer) = new_baudrate;
380 		feature_buffer[4] |= data_bits;   /* assign data bits in 2 bit space ( max 3 ) */
381 		/* 1 bit gap */
382 		feature_buffer[4] |= (stop_bits << 3);   /* assign stop bits in 1 bit space */
383 		feature_buffer[4] |= (parity_enable << 4);   /* assign parity flag in 1 bit space */
384 		feature_buffer[4] |= (parity_type << 5);   /* assign parity type in 1 bit space */
385 		/* 1 bit gap */
386 		feature_buffer[4] |= (reset << 7);   /* assign reset at end of byte, 1 bit space */
387 
388 		dbg("%s - device is being sent this feature report:",
389 								__func__);
390 		dbg("%s - %02X - %02X - %02X - %02X - %02X", __func__,
391 			feature_buffer[0], feature_buffer[1],
392 			feature_buffer[2], feature_buffer[3],
393 			feature_buffer[4]);
394 
395 		do {
396 			retval = usb_control_msg(port->serial->dev,
397 					usb_sndctrlpipe(port->serial->dev, 0),
398 					HID_REQ_SET_REPORT,
399 					USB_DIR_OUT | USB_RECIP_INTERFACE | USB_TYPE_CLASS,
400 					0x0300, 0, feature_buffer,
401 					sizeof(feature_buffer), 500);
402 
403 			if (tries++ >= 3)
404 				break;
405 
406 		} while (retval != sizeof(feature_buffer) &&
407 			 retval != -ENODEV);
408 
409 		if (retval != sizeof(feature_buffer)) {
410 			dev_err(&port->dev, "%s - failed sending serial "
411 				"line settings - %d\n", __func__, retval);
412 			cypress_set_dead(port);
413 		} else {
414 			spin_lock_irqsave(&priv->lock, flags);
415 			priv->baud_rate = new_baudrate;
416 			priv->current_config = feature_buffer[4];
417 			spin_unlock_irqrestore(&priv->lock, flags);
418 			/* If we asked for a speed change encode it */
419 			if (baud_rate)
420 				tty_encode_baud_rate(tty,
421 					new_baudrate, new_baudrate);
422 		}
423 	break;
424 	case CYPRESS_GET_CONFIG:
425 		if (priv->get_cfg_unsafe) {
426 			/* Not implemented for this device,
427 			   and if we try to do it we're likely
428 			   to crash the hardware. */
429 			return -ENOTTY;
430 		}
431 		dbg("%s - retreiving serial line settings", __func__);
432 		/* set initial values in feature buffer */
433 		memset(feature_buffer, 0, sizeof(feature_buffer));
434 
435 		do {
436 			retval = usb_control_msg(port->serial->dev,
437 					usb_rcvctrlpipe(port->serial->dev, 0),
438 					HID_REQ_GET_REPORT,
439 					USB_DIR_IN | USB_RECIP_INTERFACE | USB_TYPE_CLASS,
440 					0x0300, 0, feature_buffer,
441 					sizeof(feature_buffer), 500);
442 
443 			if (tries++ >= 3)
444 				break;
445 		} while (retval != sizeof(feature_buffer)
446 						&& retval != -ENODEV);
447 
448 		if (retval != sizeof(feature_buffer)) {
449 			dev_err(&port->dev, "%s - failed to retrieve serial "
450 				"line settings - %d\n", __func__, retval);
451 			cypress_set_dead(port);
452 			return retval;
453 		} else {
454 			spin_lock_irqsave(&priv->lock, flags);
455 			/* store the config in one byte, and later
456 			   use bit masks to check values */
457 			priv->current_config = feature_buffer[4];
458 			priv->baud_rate = *((u_int32_t *)feature_buffer);
459 			spin_unlock_irqrestore(&priv->lock, flags);
460 		}
461 	}
462 	spin_lock_irqsave(&priv->lock, flags);
463 	++priv->cmd_count;
464 	spin_unlock_irqrestore(&priv->lock, flags);
465 
466 	return retval;
467 } /* cypress_serial_control */
468 
469 
470 static void cypress_set_dead(struct usb_serial_port *port)
471 {
472 	struct cypress_private *priv = usb_get_serial_port_data(port);
473 	unsigned long flags;
474 
475 	spin_lock_irqsave(&priv->lock, flags);
476 	if (!priv->comm_is_ok) {
477 		spin_unlock_irqrestore(&priv->lock, flags);
478 		return;
479 	}
480 	priv->comm_is_ok = 0;
481 	spin_unlock_irqrestore(&priv->lock, flags);
482 
483 	dev_err(&port->dev, "cypress_m8 suspending failing port %d - "
484 		"interval might be too short\n", port->number);
485 }
486 
487 
488 /*****************************************************************************
489  * Cypress serial driver functions
490  *****************************************************************************/
491 
492 
493 static int generic_startup(struct usb_serial *serial)
494 {
495 	struct cypress_private *priv;
496 	struct usb_serial_port *port = serial->port[0];
497 
498 	dbg("%s - port %d", __func__, port->number);
499 
500 	priv = kzalloc(sizeof(struct cypress_private), GFP_KERNEL);
501 	if (!priv)
502 		return -ENOMEM;
503 
504 	priv->comm_is_ok = !0;
505 	spin_lock_init(&priv->lock);
506 	priv->buf = cypress_buf_alloc(CYPRESS_BUF_SIZE);
507 	if (priv->buf == NULL) {
508 		kfree(priv);
509 		return -ENOMEM;
510 	}
511 	init_waitqueue_head(&priv->delta_msr_wait);
512 
513 	usb_reset_configuration(serial->dev);
514 
515 	priv->cmd_ctrl = 0;
516 	priv->line_control = 0;
517 	priv->termios_initialized = 0;
518 	priv->rx_flags = 0;
519 	/* Default packet format setting is determined by packet size.
520 	   Anything with a size larger then 9 must have a separate
521 	   count field since the 3 bit count field is otherwise too
522 	   small.  Otherwise we can use the slightly more compact
523 	   format.  This is in accordance with the cypress_m8 serial
524 	   converter app note. */
525 	if (port->interrupt_out_size > 9)
526 		priv->pkt_fmt = packet_format_1;
527 	else
528 		priv->pkt_fmt = packet_format_2;
529 
530 	if (interval > 0) {
531 		priv->write_urb_interval = interval;
532 		priv->read_urb_interval = interval;
533 		dbg("%s - port %d read & write intervals forced to %d",
534 		    __func__, port->number, interval);
535 	} else {
536 		priv->write_urb_interval = port->interrupt_out_urb->interval;
537 		priv->read_urb_interval = port->interrupt_in_urb->interval;
538 		dbg("%s - port %d intervals: read=%d write=%d",
539 		    __func__, port->number,
540 		    priv->read_urb_interval, priv->write_urb_interval);
541 	}
542 	usb_set_serial_port_data(port, priv);
543 
544 	return 0;
545 }
546 
547 
548 static int cypress_earthmate_startup(struct usb_serial *serial)
549 {
550 	struct cypress_private *priv;
551 	struct usb_serial_port *port = serial->port[0];
552 
553 	dbg("%s", __func__);
554 
555 	if (generic_startup(serial)) {
556 		dbg("%s - Failed setting up port %d", __func__,
557 				port->number);
558 		return 1;
559 	}
560 
561 	priv = usb_get_serial_port_data(port);
562 	priv->chiptype = CT_EARTHMATE;
563 	/* All Earthmate devices use the separated-count packet
564 	   format!  Idiotic. */
565 	priv->pkt_fmt = packet_format_1;
566 	if (serial->dev->descriptor.idProduct !=
567 				cpu_to_le16(PRODUCT_ID_EARTHMATEUSB)) {
568 		/* The old original USB Earthmate seemed able to
569 		   handle GET_CONFIG requests; everything they've
570 		   produced since that time crashes if this command is
571 		   attempted :-( */
572 		dbg("%s - Marking this device as unsafe for GET_CONFIG "
573 		    "commands", __func__);
574 		priv->get_cfg_unsafe = !0;
575 	}
576 
577 	return 0;
578 } /* cypress_earthmate_startup */
579 
580 
581 static int cypress_hidcom_startup(struct usb_serial *serial)
582 {
583 	struct cypress_private *priv;
584 
585 	dbg("%s", __func__);
586 
587 	if (generic_startup(serial)) {
588 		dbg("%s - Failed setting up port %d", __func__,
589 				serial->port[0]->number);
590 		return 1;
591 	}
592 
593 	priv = usb_get_serial_port_data(serial->port[0]);
594 	priv->chiptype = CT_CYPHIDCOM;
595 
596 	return 0;
597 } /* cypress_hidcom_startup */
598 
599 
600 static int cypress_ca42v2_startup(struct usb_serial *serial)
601 {
602 	struct cypress_private *priv;
603 
604 	dbg("%s", __func__);
605 
606 	if (generic_startup(serial)) {
607 		dbg("%s - Failed setting up port %d", __func__,
608 				serial->port[0]->number);
609 		return 1;
610 	}
611 
612 	priv = usb_get_serial_port_data(serial->port[0]);
613 	priv->chiptype = CT_CA42V2;
614 
615 	return 0;
616 } /* cypress_ca42v2_startup */
617 
618 
619 static void cypress_release(struct usb_serial *serial)
620 {
621 	struct cypress_private *priv;
622 
623 	dbg("%s - port %d", __func__, serial->port[0]->number);
624 
625 	/* all open ports are closed at this point */
626 
627 	priv = usb_get_serial_port_data(serial->port[0]);
628 
629 	if (priv) {
630 		cypress_buf_free(priv->buf);
631 		kfree(priv);
632 	}
633 }
634 
635 
636 static int cypress_open(struct tty_struct *tty,
637 			struct usb_serial_port *port, struct file *filp)
638 {
639 	struct cypress_private *priv = usb_get_serial_port_data(port);
640 	struct usb_serial *serial = port->serial;
641 	unsigned long flags;
642 	int result = 0;
643 
644 	dbg("%s - port %d", __func__, port->number);
645 
646 	if (!priv->comm_is_ok)
647 		return -EIO;
648 
649 	/* clear halts before open */
650 	usb_clear_halt(serial->dev, 0x81);
651 	usb_clear_halt(serial->dev, 0x02);
652 
653 	spin_lock_irqsave(&priv->lock, flags);
654 	/* reset read/write statistics */
655 	priv->bytes_in = 0;
656 	priv->bytes_out = 0;
657 	priv->cmd_count = 0;
658 	priv->rx_flags = 0;
659 	spin_unlock_irqrestore(&priv->lock, flags);
660 
661 	/* Set termios */
662 	result = cypress_write(tty, port, NULL, 0);
663 
664 	if (result) {
665 		dev_err(&port->dev,
666 			"%s - failed setting the control lines - error %d\n",
667 							__func__, result);
668 		return result;
669 	} else
670 		dbg("%s - success setting the control lines", __func__);
671 
672 	if (tty)
673 		cypress_set_termios(tty, port, &priv->tmp_termios);
674 
675 	/* setup the port and start reading from the device */
676 	if (!port->interrupt_in_urb) {
677 		dev_err(&port->dev, "%s - interrupt_in_urb is empty!\n",
678 			__func__);
679 		return -1;
680 	}
681 
682 	usb_fill_int_urb(port->interrupt_in_urb, serial->dev,
683 		usb_rcvintpipe(serial->dev, port->interrupt_in_endpointAddress),
684 		port->interrupt_in_urb->transfer_buffer,
685 		port->interrupt_in_urb->transfer_buffer_length,
686 		cypress_read_int_callback, port, priv->read_urb_interval);
687 	result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
688 
689 	if (result) {
690 		dev_err(&port->dev,
691 			"%s - failed submitting read urb, error %d\n",
692 							__func__, result);
693 		cypress_set_dead(port);
694 	}
695 	port->port.drain_delay = 256;
696 	return result;
697 } /* cypress_open */
698 
699 static void cypress_dtr_rts(struct usb_serial_port *port, int on)
700 {
701 	struct cypress_private *priv = usb_get_serial_port_data(port);
702 	/* drop dtr and rts */
703 	priv = usb_get_serial_port_data(port);
704 	spin_lock_irq(&priv->lock);
705 	if (on == 0)
706 		priv->line_control = 0;
707 	else
708 		priv->line_control = CONTROL_DTR | CONTROL_RTS;
709 	priv->cmd_ctrl = 1;
710 	spin_unlock_irq(&priv->lock);
711 	cypress_write(NULL, port, NULL, 0);
712 }
713 
714 static void cypress_close(struct usb_serial_port *port)
715 {
716 	struct cypress_private *priv = usb_get_serial_port_data(port);
717 
718 	dbg("%s - port %d", __func__, port->number);
719 
720 	/* writing is potentially harmful, lock must be taken */
721 	mutex_lock(&port->serial->disc_mutex);
722 	if (port->serial->disconnected) {
723 		mutex_unlock(&port->serial->disc_mutex);
724 		return;
725 	}
726 	cypress_buf_clear(priv->buf);
727 	dbg("%s - stopping urbs", __func__);
728 	usb_kill_urb(port->interrupt_in_urb);
729 	usb_kill_urb(port->interrupt_out_urb);
730 
731 
732 	if (stats)
733 		dev_info(&port->dev, "Statistics: %d Bytes In | %d Bytes Out | %d Commands Issued\n",
734 			priv->bytes_in, priv->bytes_out, priv->cmd_count);
735 	mutex_unlock(&port->serial->disc_mutex);
736 } /* cypress_close */
737 
738 
739 static int cypress_write(struct tty_struct *tty, struct usb_serial_port *port,
740 					const unsigned char *buf, int count)
741 {
742 	struct cypress_private *priv = usb_get_serial_port_data(port);
743 	unsigned long flags;
744 
745 	dbg("%s - port %d, %d bytes", __func__, port->number, count);
746 
747 	/* line control commands, which need to be executed immediately,
748 	   are not put into the buffer for obvious reasons.
749 	 */
750 	if (priv->cmd_ctrl) {
751 		count = 0;
752 		goto finish;
753 	}
754 
755 	if (!count)
756 		return count;
757 
758 	spin_lock_irqsave(&priv->lock, flags);
759 	count = cypress_buf_put(priv->buf, buf, count);
760 	spin_unlock_irqrestore(&priv->lock, flags);
761 
762 finish:
763 	cypress_send(port);
764 
765 	return count;
766 } /* cypress_write */
767 
768 
769 static void cypress_send(struct usb_serial_port *port)
770 {
771 	int count = 0, result, offset, actual_size;
772 	struct cypress_private *priv = usb_get_serial_port_data(port);
773 	unsigned long flags;
774 
775 	if (!priv->comm_is_ok)
776 		return;
777 
778 	dbg("%s - port %d", __func__, port->number);
779 	dbg("%s - interrupt out size is %d", __func__,
780 						port->interrupt_out_size);
781 
782 	spin_lock_irqsave(&priv->lock, flags);
783 	if (priv->write_urb_in_use) {
784 		dbg("%s - can't write, urb in use", __func__);
785 		spin_unlock_irqrestore(&priv->lock, flags);
786 		return;
787 	}
788 	spin_unlock_irqrestore(&priv->lock, flags);
789 
790 	/* clear buffer */
791 	memset(port->interrupt_out_urb->transfer_buffer, 0,
792 						port->interrupt_out_size);
793 
794 	spin_lock_irqsave(&priv->lock, flags);
795 	switch (priv->pkt_fmt) {
796 	default:
797 	case packet_format_1:
798 		/* this is for the CY7C64013... */
799 		offset = 2;
800 		port->interrupt_out_buffer[0] = priv->line_control;
801 		break;
802 	case packet_format_2:
803 		/* this is for the CY7C63743... */
804 		offset = 1;
805 		port->interrupt_out_buffer[0] = priv->line_control;
806 		break;
807 	}
808 
809 	if (priv->line_control & CONTROL_RESET)
810 		priv->line_control &= ~CONTROL_RESET;
811 
812 	if (priv->cmd_ctrl) {
813 		priv->cmd_count++;
814 		dbg("%s - line control command being issued", __func__);
815 		spin_unlock_irqrestore(&priv->lock, flags);
816 		goto send;
817 	} else
818 		spin_unlock_irqrestore(&priv->lock, flags);
819 
820 	count = cypress_buf_get(priv->buf, &port->interrupt_out_buffer[offset],
821 				port->interrupt_out_size-offset);
822 
823 	if (count == 0)
824 		return;
825 
826 	switch (priv->pkt_fmt) {
827 	default:
828 	case packet_format_1:
829 		port->interrupt_out_buffer[1] = count;
830 		break;
831 	case packet_format_2:
832 		port->interrupt_out_buffer[0] |= count;
833 	}
834 
835 	dbg("%s - count is %d", __func__, count);
836 
837 send:
838 	spin_lock_irqsave(&priv->lock, flags);
839 	priv->write_urb_in_use = 1;
840 	spin_unlock_irqrestore(&priv->lock, flags);
841 
842 	if (priv->cmd_ctrl)
843 		actual_size = 1;
844 	else
845 		actual_size = count +
846 			      (priv->pkt_fmt == packet_format_1 ? 2 : 1);
847 
848 	usb_serial_debug_data(debug, &port->dev, __func__,
849 		port->interrupt_out_size,
850 		port->interrupt_out_urb->transfer_buffer);
851 
852 	usb_fill_int_urb(port->interrupt_out_urb, port->serial->dev,
853 		usb_sndintpipe(port->serial->dev, port->interrupt_out_endpointAddress),
854 		port->interrupt_out_buffer, port->interrupt_out_size,
855 		cypress_write_int_callback, port, priv->write_urb_interval);
856 	result = usb_submit_urb(port->interrupt_out_urb, GFP_ATOMIC);
857 	if (result) {
858 		dev_err(&port->dev,
859 				"%s - failed submitting write urb, error %d\n",
860 							__func__, result);
861 		priv->write_urb_in_use = 0;
862 		cypress_set_dead(port);
863 	}
864 
865 	spin_lock_irqsave(&priv->lock, flags);
866 	if (priv->cmd_ctrl)
867 		priv->cmd_ctrl = 0;
868 
869 	/* do not count the line control and size bytes */
870 	priv->bytes_out += count;
871 	spin_unlock_irqrestore(&priv->lock, flags);
872 
873 	usb_serial_port_softint(port);
874 } /* cypress_send */
875 
876 
877 /* returns how much space is available in the soft buffer */
878 static int cypress_write_room(struct tty_struct *tty)
879 {
880 	struct usb_serial_port *port = tty->driver_data;
881 	struct cypress_private *priv = usb_get_serial_port_data(port);
882 	int room = 0;
883 	unsigned long flags;
884 
885 	dbg("%s - port %d", __func__, port->number);
886 
887 	spin_lock_irqsave(&priv->lock, flags);
888 	room = cypress_buf_space_avail(priv->buf);
889 	spin_unlock_irqrestore(&priv->lock, flags);
890 
891 	dbg("%s - returns %d", __func__, room);
892 	return room;
893 }
894 
895 
896 static int cypress_tiocmget(struct tty_struct *tty, struct file *file)
897 {
898 	struct usb_serial_port *port = tty->driver_data;
899 	struct cypress_private *priv = usb_get_serial_port_data(port);
900 	__u8 status, control;
901 	unsigned int result = 0;
902 	unsigned long flags;
903 
904 	dbg("%s - port %d", __func__, port->number);
905 
906 	spin_lock_irqsave(&priv->lock, flags);
907 	control = priv->line_control;
908 	status = priv->current_status;
909 	spin_unlock_irqrestore(&priv->lock, flags);
910 
911 	result = ((control & CONTROL_DTR)        ? TIOCM_DTR : 0)
912 		| ((control & CONTROL_RTS)       ? TIOCM_RTS : 0)
913 		| ((status & UART_CTS)        ? TIOCM_CTS : 0)
914 		| ((status & UART_DSR)        ? TIOCM_DSR : 0)
915 		| ((status & UART_RI)         ? TIOCM_RI  : 0)
916 		| ((status & UART_CD)         ? TIOCM_CD  : 0);
917 
918 	dbg("%s - result = %x", __func__, result);
919 
920 	return result;
921 }
922 
923 
924 static int cypress_tiocmset(struct tty_struct *tty, struct file *file,
925 			       unsigned int set, unsigned int clear)
926 {
927 	struct usb_serial_port *port = tty->driver_data;
928 	struct cypress_private *priv = usb_get_serial_port_data(port);
929 	unsigned long flags;
930 
931 	dbg("%s - port %d", __func__, port->number);
932 
933 	spin_lock_irqsave(&priv->lock, flags);
934 	if (set & TIOCM_RTS)
935 		priv->line_control |= CONTROL_RTS;
936 	if (set & TIOCM_DTR)
937 		priv->line_control |= CONTROL_DTR;
938 	if (clear & TIOCM_RTS)
939 		priv->line_control &= ~CONTROL_RTS;
940 	if (clear & TIOCM_DTR)
941 		priv->line_control &= ~CONTROL_DTR;
942 	priv->cmd_ctrl = 1;
943 	spin_unlock_irqrestore(&priv->lock, flags);
944 
945 	return cypress_write(tty, port, NULL, 0);
946 }
947 
948 
949 static int cypress_ioctl(struct tty_struct *tty, struct file *file,
950 					unsigned int cmd, unsigned long arg)
951 {
952 	struct usb_serial_port *port = tty->driver_data;
953 	struct cypress_private *priv = usb_get_serial_port_data(port);
954 
955 	dbg("%s - port %d, cmd 0x%.4x", __func__, port->number, cmd);
956 
957 	switch (cmd) {
958 	/* This code comes from drivers/char/serial.c and ftdi_sio.c */
959 	case TIOCMIWAIT:
960 		while (priv != NULL) {
961 			interruptible_sleep_on(&priv->delta_msr_wait);
962 			/* see if a signal did it */
963 			if (signal_pending(current))
964 				return -ERESTARTSYS;
965 			else {
966 				char diff = priv->diff_status;
967 				if (diff == 0)
968 					return -EIO; /* no change => error */
969 
970 				/* consume all events */
971 				priv->diff_status = 0;
972 
973 				/* return 0 if caller wanted to know about
974 				   these bits */
975 				if (((arg & TIOCM_RNG) && (diff & UART_RI)) ||
976 				    ((arg & TIOCM_DSR) && (diff & UART_DSR)) ||
977 				    ((arg & TIOCM_CD) && (diff & UART_CD)) ||
978 				    ((arg & TIOCM_CTS) && (diff & UART_CTS)))
979 					return 0;
980 				/* otherwise caller can't care less about what
981 				 * happened, and so we continue to wait for
982 				 * more events.
983 				 */
984 			}
985 		}
986 		return 0;
987 	default:
988 		break;
989 	}
990 	dbg("%s - arg not supported - it was 0x%04x - check include/asm/ioctls.h", __func__, cmd);
991 	return -ENOIOCTLCMD;
992 } /* cypress_ioctl */
993 
994 
995 static void cypress_set_termios(struct tty_struct *tty,
996 	struct usb_serial_port *port, struct ktermios *old_termios)
997 {
998 	struct cypress_private *priv = usb_get_serial_port_data(port);
999 	int data_bits, stop_bits, parity_type, parity_enable;
1000 	unsigned cflag, iflag;
1001 	unsigned long flags;
1002 	__u8 oldlines;
1003 	int linechange = 0;
1004 
1005 	dbg("%s - port %d", __func__, port->number);
1006 
1007 	spin_lock_irqsave(&priv->lock, flags);
1008 	if (!priv->termios_initialized) {
1009 		if (priv->chiptype == CT_EARTHMATE) {
1010 			*(tty->termios) = tty_std_termios;
1011 			tty->termios->c_cflag = B4800 | CS8 | CREAD | HUPCL |
1012 				CLOCAL;
1013 			tty->termios->c_ispeed = 4800;
1014 			tty->termios->c_ospeed = 4800;
1015 		} else if (priv->chiptype == CT_CYPHIDCOM) {
1016 			*(tty->termios) = tty_std_termios;
1017 			tty->termios->c_cflag = B9600 | CS8 | CREAD | HUPCL |
1018 				CLOCAL;
1019 			tty->termios->c_ispeed = 9600;
1020 			tty->termios->c_ospeed = 9600;
1021 		} else if (priv->chiptype == CT_CA42V2) {
1022 			*(tty->termios) = tty_std_termios;
1023 			tty->termios->c_cflag = B9600 | CS8 | CREAD | HUPCL |
1024 				CLOCAL;
1025 			tty->termios->c_ispeed = 9600;
1026 			tty->termios->c_ospeed = 9600;
1027 		}
1028 		priv->termios_initialized = 1;
1029 	}
1030 	spin_unlock_irqrestore(&priv->lock, flags);
1031 
1032 	/* Unsupported features need clearing */
1033 	tty->termios->c_cflag &= ~(CMSPAR|CRTSCTS);
1034 
1035 	cflag = tty->termios->c_cflag;
1036 	iflag = tty->termios->c_iflag;
1037 
1038 	/* check if there are new settings */
1039 	if (old_termios) {
1040 		spin_lock_irqsave(&priv->lock, flags);
1041 		priv->tmp_termios = *(tty->termios);
1042 		spin_unlock_irqrestore(&priv->lock, flags);
1043 	}
1044 
1045 	/* set number of data bits, parity, stop bits */
1046 	/* when parity is disabled the parity type bit is ignored */
1047 
1048 	/* 1 means 2 stop bits, 0 means 1 stop bit */
1049 	stop_bits = cflag & CSTOPB ? 1 : 0;
1050 
1051 	if (cflag & PARENB) {
1052 		parity_enable = 1;
1053 		/* 1 means odd parity, 0 means even parity */
1054 		parity_type = cflag & PARODD ? 1 : 0;
1055 	} else
1056 		parity_enable = parity_type = 0;
1057 
1058 	switch (cflag & CSIZE) {
1059 	case CS5:
1060 		data_bits = 0;
1061 		break;
1062 	case CS6:
1063 		data_bits = 1;
1064 		break;
1065 	case CS7:
1066 		data_bits = 2;
1067 		break;
1068 	case CS8:
1069 		data_bits = 3;
1070 		break;
1071 	default:
1072 		dev_err(&port->dev, "%s - CSIZE was set, but not CS5-CS8\n",
1073 			__func__);
1074 		data_bits = 3;
1075 	}
1076 	spin_lock_irqsave(&priv->lock, flags);
1077 	oldlines = priv->line_control;
1078 	if ((cflag & CBAUD) == B0) {
1079 		/* drop dtr and rts */
1080 		dbg("%s - dropping the lines, baud rate 0bps", __func__);
1081 		priv->line_control &= ~(CONTROL_DTR | CONTROL_RTS);
1082 	} else
1083 		priv->line_control = (CONTROL_DTR | CONTROL_RTS);
1084 	spin_unlock_irqrestore(&priv->lock, flags);
1085 
1086 	dbg("%s - sending %d stop_bits, %d parity_enable, %d parity_type, "
1087 			"%d data_bits (+5)", __func__, stop_bits,
1088 			parity_enable, parity_type, data_bits);
1089 
1090 	cypress_serial_control(tty, port, tty_get_baud_rate(tty),
1091 			data_bits, stop_bits,
1092 			parity_enable, parity_type,
1093 			0, CYPRESS_SET_CONFIG);
1094 
1095 	/* we perform a CYPRESS_GET_CONFIG so that the current settings are
1096 	 * filled into the private structure this should confirm that all is
1097 	 * working if it returns what we just set */
1098 	cypress_serial_control(tty, port, 0, 0, 0, 0, 0, 0, CYPRESS_GET_CONFIG);
1099 
1100 	/* Here we can define custom tty settings for devices; the main tty
1101 	 * termios flag base comes from empeg.c */
1102 
1103 	spin_lock_irqsave(&priv->lock, flags);
1104 	if (priv->chiptype == CT_EARTHMATE && priv->baud_rate == 4800) {
1105 		dbg("Using custom termios settings for a baud rate of "
1106 				"4800bps.");
1107 		/* define custom termios settings for NMEA protocol */
1108 
1109 		tty->termios->c_iflag /* input modes - */
1110 			&= ~(IGNBRK  /* disable ignore break */
1111 			| BRKINT     /* disable break causes interrupt */
1112 			| PARMRK     /* disable mark parity errors */
1113 			| ISTRIP     /* disable clear high bit of input char */
1114 			| INLCR      /* disable translate NL to CR */
1115 			| IGNCR      /* disable ignore CR */
1116 			| ICRNL      /* disable translate CR to NL */
1117 			| IXON);     /* disable enable XON/XOFF flow control */
1118 
1119 		tty->termios->c_oflag /* output modes */
1120 			&= ~OPOST;    /* disable postprocess output char */
1121 
1122 		tty->termios->c_lflag /* line discipline modes */
1123 			&= ~(ECHO     /* disable echo input characters */
1124 			| ECHONL      /* disable echo new line */
1125 			| ICANON      /* disable erase, kill, werase, and rprnt
1126 					 special characters */
1127 			| ISIG        /* disable interrupt, quit, and suspend
1128 					 special characters */
1129 			| IEXTEN);    /* disable non-POSIX special characters */
1130 	} /* CT_CYPHIDCOM: Application should handle this for device */
1131 
1132 	linechange = (priv->line_control != oldlines);
1133 	spin_unlock_irqrestore(&priv->lock, flags);
1134 
1135 	/* if necessary, set lines */
1136 	if (linechange) {
1137 		priv->cmd_ctrl = 1;
1138 		cypress_write(tty, port, NULL, 0);
1139 	}
1140 } /* cypress_set_termios */
1141 
1142 
1143 /* returns amount of data still left in soft buffer */
1144 static int cypress_chars_in_buffer(struct tty_struct *tty)
1145 {
1146 	struct usb_serial_port *port = tty->driver_data;
1147 	struct cypress_private *priv = usb_get_serial_port_data(port);
1148 	int chars = 0;
1149 	unsigned long flags;
1150 
1151 	dbg("%s - port %d", __func__, port->number);
1152 
1153 	spin_lock_irqsave(&priv->lock, flags);
1154 	chars = cypress_buf_data_avail(priv->buf);
1155 	spin_unlock_irqrestore(&priv->lock, flags);
1156 
1157 	dbg("%s - returns %d", __func__, chars);
1158 	return chars;
1159 }
1160 
1161 
1162 static void cypress_throttle(struct tty_struct *tty)
1163 {
1164 	struct usb_serial_port *port = tty->driver_data;
1165 	struct cypress_private *priv = usb_get_serial_port_data(port);
1166 	unsigned long flags;
1167 
1168 	dbg("%s - port %d", __func__, port->number);
1169 
1170 	spin_lock_irqsave(&priv->lock, flags);
1171 	priv->rx_flags = THROTTLED;
1172 	spin_unlock_irqrestore(&priv->lock, flags);
1173 }
1174 
1175 
1176 static void cypress_unthrottle(struct tty_struct *tty)
1177 {
1178 	struct usb_serial_port *port = tty->driver_data;
1179 	struct cypress_private *priv = usb_get_serial_port_data(port);
1180 	int actually_throttled, result;
1181 	unsigned long flags;
1182 
1183 	dbg("%s - port %d", __func__, port->number);
1184 
1185 	spin_lock_irqsave(&priv->lock, flags);
1186 	actually_throttled = priv->rx_flags & ACTUALLY_THROTTLED;
1187 	priv->rx_flags = 0;
1188 	spin_unlock_irqrestore(&priv->lock, flags);
1189 
1190 	if (!priv->comm_is_ok)
1191 		return;
1192 
1193 	if (actually_throttled) {
1194 		port->interrupt_in_urb->dev = port->serial->dev;
1195 
1196 		result = usb_submit_urb(port->interrupt_in_urb, GFP_ATOMIC);
1197 		if (result) {
1198 			dev_err(&port->dev, "%s - failed submitting read urb, "
1199 					"error %d\n", __func__, result);
1200 			cypress_set_dead(port);
1201 		}
1202 	}
1203 }
1204 
1205 
1206 static void cypress_read_int_callback(struct urb *urb)
1207 {
1208 	struct usb_serial_port *port = urb->context;
1209 	struct cypress_private *priv = usb_get_serial_port_data(port);
1210 	struct tty_struct *tty;
1211 	unsigned char *data = urb->transfer_buffer;
1212 	unsigned long flags;
1213 	char tty_flag = TTY_NORMAL;
1214 	int havedata = 0;
1215 	int bytes = 0;
1216 	int result;
1217 	int i = 0;
1218 	int status = urb->status;
1219 
1220 	dbg("%s - port %d", __func__, port->number);
1221 
1222 	switch (status) {
1223 	case 0: /* success */
1224 		break;
1225 	case -ECONNRESET:
1226 	case -ENOENT:
1227 	case -ESHUTDOWN:
1228 		/* precursor to disconnect so just go away */
1229 		return;
1230 	case -EPIPE:
1231 		/* Can't call usb_clear_halt while in_interrupt */
1232 		/* FALLS THROUGH */
1233 	default:
1234 		/* something ugly is going on... */
1235 		dev_err(&urb->dev->dev,
1236 			"%s - unexpected nonzero read status received: %d\n",
1237 							__func__, status);
1238 		cypress_set_dead(port);
1239 		return;
1240 	}
1241 
1242 	spin_lock_irqsave(&priv->lock, flags);
1243 	if (priv->rx_flags & THROTTLED) {
1244 		dbg("%s - now throttling", __func__);
1245 		priv->rx_flags |= ACTUALLY_THROTTLED;
1246 		spin_unlock_irqrestore(&priv->lock, flags);
1247 		return;
1248 	}
1249 	spin_unlock_irqrestore(&priv->lock, flags);
1250 
1251 	tty = tty_port_tty_get(&port->port);
1252 	if (!tty) {
1253 		dbg("%s - bad tty pointer - exiting", __func__);
1254 		return;
1255 	}
1256 
1257 	spin_lock_irqsave(&priv->lock, flags);
1258 	result = urb->actual_length;
1259 	switch (priv->pkt_fmt) {
1260 	default:
1261 	case packet_format_1:
1262 		/* This is for the CY7C64013... */
1263 		priv->current_status = data[0] & 0xF8;
1264 		bytes = data[1] + 2;
1265 		i = 2;
1266 		if (bytes > 2)
1267 			havedata = 1;
1268 		break;
1269 	case packet_format_2:
1270 		/* This is for the CY7C63743... */
1271 		priv->current_status = data[0] & 0xF8;
1272 		bytes = (data[0] & 0x07) + 1;
1273 		i = 1;
1274 		if (bytes > 1)
1275 			havedata = 1;
1276 		break;
1277 	}
1278 	spin_unlock_irqrestore(&priv->lock, flags);
1279 	if (result < bytes) {
1280 		dbg("%s - wrong packet size - received %d bytes but packet "
1281 		    "said %d bytes", __func__, result, bytes);
1282 		goto continue_read;
1283 	}
1284 
1285 	usb_serial_debug_data(debug, &port->dev, __func__,
1286 						urb->actual_length, data);
1287 
1288 	spin_lock_irqsave(&priv->lock, flags);
1289 	/* check to see if status has changed */
1290 	if (priv->current_status != priv->prev_status) {
1291 		priv->diff_status |= priv->current_status ^
1292 			priv->prev_status;
1293 		wake_up_interruptible(&priv->delta_msr_wait);
1294 		priv->prev_status = priv->current_status;
1295 	}
1296 	spin_unlock_irqrestore(&priv->lock, flags);
1297 
1298 	/* hangup, as defined in acm.c... this might be a bad place for it
1299 	 * though */
1300 	if (tty && !(tty->termios->c_cflag & CLOCAL) &&
1301 			!(priv->current_status & UART_CD)) {
1302 		dbg("%s - calling hangup", __func__);
1303 		tty_hangup(tty);
1304 		goto continue_read;
1305 	}
1306 
1307 	/* There is one error bit... I'm assuming it is a parity error
1308 	 * indicator as the generic firmware will set this bit to 1 if a
1309 	 * parity error occurs.
1310 	 * I can not find reference to any other error events. */
1311 	spin_lock_irqsave(&priv->lock, flags);
1312 	if (priv->current_status & CYP_ERROR) {
1313 		spin_unlock_irqrestore(&priv->lock, flags);
1314 		tty_flag = TTY_PARITY;
1315 		dbg("%s - Parity Error detected", __func__);
1316 	} else
1317 		spin_unlock_irqrestore(&priv->lock, flags);
1318 
1319 	/* process read if there is data other than line status */
1320 	if (tty && (bytes > i)) {
1321 		bytes = tty_buffer_request_room(tty, bytes);
1322 		for (; i < bytes ; ++i) {
1323 			dbg("pushing byte number %d - %d - %c", i, data[i],
1324 					data[i]);
1325 			tty_insert_flip_char(tty, data[i], tty_flag);
1326 		}
1327 		tty_flip_buffer_push(tty);
1328 	}
1329 
1330 	spin_lock_irqsave(&priv->lock, flags);
1331 	/* control and status byte(s) are also counted */
1332 	priv->bytes_in += bytes;
1333 	spin_unlock_irqrestore(&priv->lock, flags);
1334 
1335 continue_read:
1336 	tty_kref_put(tty);
1337 
1338 	/* Continue trying to always read... unless the port has closed. */
1339 
1340 	if (port->port.count > 0 && priv->comm_is_ok) {
1341 		usb_fill_int_urb(port->interrupt_in_urb, port->serial->dev,
1342 				usb_rcvintpipe(port->serial->dev,
1343 					port->interrupt_in_endpointAddress),
1344 				port->interrupt_in_urb->transfer_buffer,
1345 				port->interrupt_in_urb->transfer_buffer_length,
1346 				cypress_read_int_callback, port,
1347 				priv->read_urb_interval);
1348 		result = usb_submit_urb(port->interrupt_in_urb, GFP_ATOMIC);
1349 		if (result) {
1350 			dev_err(&urb->dev->dev, "%s - failed resubmitting "
1351 					"read urb, error %d\n", __func__,
1352 					result);
1353 			cypress_set_dead(port);
1354 		}
1355 	}
1356 
1357 	return;
1358 } /* cypress_read_int_callback */
1359 
1360 
1361 static void cypress_write_int_callback(struct urb *urb)
1362 {
1363 	struct usb_serial_port *port = urb->context;
1364 	struct cypress_private *priv = usb_get_serial_port_data(port);
1365 	int result;
1366 	int status = urb->status;
1367 
1368 	dbg("%s - port %d", __func__, port->number);
1369 
1370 	switch (status) {
1371 	case 0:
1372 		/* success */
1373 		break;
1374 	case -ECONNRESET:
1375 	case -ENOENT:
1376 	case -ESHUTDOWN:
1377 		/* this urb is terminated, clean up */
1378 		dbg("%s - urb shutting down with status: %d",
1379 						__func__, status);
1380 		priv->write_urb_in_use = 0;
1381 		return;
1382 	case -EPIPE: /* no break needed; clear halt and resubmit */
1383 		if (!priv->comm_is_ok)
1384 			break;
1385 		usb_clear_halt(port->serial->dev, 0x02);
1386 		/* error in the urb, so we have to resubmit it */
1387 		dbg("%s - nonzero write bulk status received: %d",
1388 			__func__, status);
1389 		port->interrupt_out_urb->transfer_buffer_length = 1;
1390 		port->interrupt_out_urb->dev = port->serial->dev;
1391 		result = usb_submit_urb(port->interrupt_out_urb, GFP_ATOMIC);
1392 		if (!result)
1393 			return;
1394 		dev_err(&urb->dev->dev,
1395 			"%s - failed resubmitting write urb, error %d\n",
1396 							__func__, result);
1397 		cypress_set_dead(port);
1398 		break;
1399 	default:
1400 		dev_err(&urb->dev->dev,
1401 			 "%s - unexpected nonzero write status received: %d\n",
1402 							__func__, status);
1403 		cypress_set_dead(port);
1404 		break;
1405 	}
1406 	priv->write_urb_in_use = 0;
1407 
1408 	/* send any buffered data */
1409 	cypress_send(port);
1410 }
1411 
1412 
1413 /*****************************************************************************
1414  * Write buffer functions - buffering code from pl2303 used
1415  *****************************************************************************/
1416 
1417 /*
1418  * cypress_buf_alloc
1419  *
1420  * Allocate a circular buffer and all associated memory.
1421  */
1422 
1423 static struct cypress_buf *cypress_buf_alloc(unsigned int size)
1424 {
1425 
1426 	struct cypress_buf *cb;
1427 
1428 
1429 	if (size == 0)
1430 		return NULL;
1431 
1432 	cb = kmalloc(sizeof(struct cypress_buf), GFP_KERNEL);
1433 	if (cb == NULL)
1434 		return NULL;
1435 
1436 	cb->buf_buf = kmalloc(size, GFP_KERNEL);
1437 	if (cb->buf_buf == NULL) {
1438 		kfree(cb);
1439 		return NULL;
1440 	}
1441 
1442 	cb->buf_size = size;
1443 	cb->buf_get = cb->buf_put = cb->buf_buf;
1444 
1445 	return cb;
1446 
1447 }
1448 
1449 
1450 /*
1451  * cypress_buf_free
1452  *
1453  * Free the buffer and all associated memory.
1454  */
1455 
1456 static void cypress_buf_free(struct cypress_buf *cb)
1457 {
1458 	if (cb) {
1459 		kfree(cb->buf_buf);
1460 		kfree(cb);
1461 	}
1462 }
1463 
1464 
1465 /*
1466  * cypress_buf_clear
1467  *
1468  * Clear out all data in the circular buffer.
1469  */
1470 
1471 static void cypress_buf_clear(struct cypress_buf *cb)
1472 {
1473 	if (cb != NULL)
1474 		cb->buf_get = cb->buf_put;
1475 		/* equivalent to a get of all data available */
1476 }
1477 
1478 
1479 /*
1480  * cypress_buf_data_avail
1481  *
1482  * Return the number of bytes of data available in the circular
1483  * buffer.
1484  */
1485 
1486 static unsigned int cypress_buf_data_avail(struct cypress_buf *cb)
1487 {
1488 	if (cb != NULL)
1489 		return (cb->buf_size + cb->buf_put - cb->buf_get)
1490 							% cb->buf_size;
1491 	else
1492 		return 0;
1493 }
1494 
1495 
1496 /*
1497  * cypress_buf_space_avail
1498  *
1499  * Return the number of bytes of space available in the circular
1500  * buffer.
1501  */
1502 
1503 static unsigned int cypress_buf_space_avail(struct cypress_buf *cb)
1504 {
1505 	if (cb != NULL)
1506 		return (cb->buf_size + cb->buf_get - cb->buf_put - 1)
1507 							% cb->buf_size;
1508 	else
1509 		return 0;
1510 }
1511 
1512 
1513 /*
1514  * cypress_buf_put
1515  *
1516  * Copy data data from a user buffer and put it into the circular buffer.
1517  * Restrict to the amount of space available.
1518  *
1519  * Return the number of bytes copied.
1520  */
1521 
1522 static unsigned int cypress_buf_put(struct cypress_buf *cb, const char *buf,
1523 	unsigned int count)
1524 {
1525 
1526 	unsigned int len;
1527 
1528 
1529 	if (cb == NULL)
1530 		return 0;
1531 
1532 	len  = cypress_buf_space_avail(cb);
1533 	if (count > len)
1534 		count = len;
1535 
1536 	if (count == 0)
1537 		return 0;
1538 
1539 	len = cb->buf_buf + cb->buf_size - cb->buf_put;
1540 	if (count > len) {
1541 		memcpy(cb->buf_put, buf, len);
1542 		memcpy(cb->buf_buf, buf+len, count - len);
1543 		cb->buf_put = cb->buf_buf + count - len;
1544 	} else {
1545 		memcpy(cb->buf_put, buf, count);
1546 		if (count < len)
1547 			cb->buf_put += count;
1548 		else /* count == len */
1549 			cb->buf_put = cb->buf_buf;
1550 	}
1551 
1552 	return count;
1553 
1554 }
1555 
1556 
1557 /*
1558  * cypress_buf_get
1559  *
1560  * Get data from the circular buffer and copy to the given buffer.
1561  * Restrict to the amount of data available.
1562  *
1563  * Return the number of bytes copied.
1564  */
1565 
1566 static unsigned int cypress_buf_get(struct cypress_buf *cb, char *buf,
1567 	unsigned int count)
1568 {
1569 
1570 	unsigned int len;
1571 
1572 
1573 	if (cb == NULL)
1574 		return 0;
1575 
1576 	len = cypress_buf_data_avail(cb);
1577 	if (count > len)
1578 		count = len;
1579 
1580 	if (count == 0)
1581 		return 0;
1582 
1583 	len = cb->buf_buf + cb->buf_size - cb->buf_get;
1584 	if (count > len) {
1585 		memcpy(buf, cb->buf_get, len);
1586 		memcpy(buf+len, cb->buf_buf, count - len);
1587 		cb->buf_get = cb->buf_buf + count - len;
1588 	} else {
1589 		memcpy(buf, cb->buf_get, count);
1590 		if (count < len)
1591 			cb->buf_get += count;
1592 		else /* count == len */
1593 			cb->buf_get = cb->buf_buf;
1594 	}
1595 
1596 	return count;
1597 
1598 }
1599 
1600 /*****************************************************************************
1601  * Module functions
1602  *****************************************************************************/
1603 
1604 static int __init cypress_init(void)
1605 {
1606 	int retval;
1607 
1608 	dbg("%s", __func__);
1609 
1610 	retval = usb_serial_register(&cypress_earthmate_device);
1611 	if (retval)
1612 		goto failed_em_register;
1613 	retval = usb_serial_register(&cypress_hidcom_device);
1614 	if (retval)
1615 		goto failed_hidcom_register;
1616 	retval = usb_serial_register(&cypress_ca42v2_device);
1617 	if (retval)
1618 		goto failed_ca42v2_register;
1619 	retval = usb_register(&cypress_driver);
1620 	if (retval)
1621 		goto failed_usb_register;
1622 
1623 	printk(KERN_INFO KBUILD_MODNAME ": " DRIVER_VERSION ":"
1624 	       DRIVER_DESC "\n");
1625 	return 0;
1626 
1627 failed_usb_register:
1628 	usb_serial_deregister(&cypress_ca42v2_device);
1629 failed_ca42v2_register:
1630 	usb_serial_deregister(&cypress_hidcom_device);
1631 failed_hidcom_register:
1632 	usb_serial_deregister(&cypress_earthmate_device);
1633 failed_em_register:
1634 	return retval;
1635 }
1636 
1637 
1638 static void __exit cypress_exit(void)
1639 {
1640 	dbg("%s", __func__);
1641 
1642 	usb_deregister(&cypress_driver);
1643 	usb_serial_deregister(&cypress_earthmate_device);
1644 	usb_serial_deregister(&cypress_hidcom_device);
1645 	usb_serial_deregister(&cypress_ca42v2_device);
1646 }
1647 
1648 
1649 module_init(cypress_init);
1650 module_exit(cypress_exit);
1651 
1652 MODULE_AUTHOR(DRIVER_AUTHOR);
1653 MODULE_DESCRIPTION(DRIVER_DESC);
1654 MODULE_VERSION(DRIVER_VERSION);
1655 MODULE_LICENSE("GPL");
1656 
1657 module_param(debug, bool, S_IRUGO | S_IWUSR);
1658 MODULE_PARM_DESC(debug, "Debug enabled or not");
1659 module_param(stats, bool, S_IRUGO | S_IWUSR);
1660 MODULE_PARM_DESC(stats, "Enable statistics or not");
1661 module_param(interval, int, S_IRUGO | S_IWUSR);
1662 MODULE_PARM_DESC(interval, "Overrides interrupt interval");
1663