xref: /openbmc/linux/drivers/usb/serial/cypress_m8.c (revision 6ee73861)
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, struct usb_serial_port *port);
176 static void cypress_close(struct usb_serial_port *port);
177 static void cypress_dtr_rts(struct usb_serial_port *port, int on);
178 static int  cypress_write(struct tty_struct *tty, struct usb_serial_port *port,
179 			const unsigned char *buf, int count);
180 static void cypress_send(struct usb_serial_port *port);
181 static int  cypress_write_room(struct tty_struct *tty);
182 static int  cypress_ioctl(struct tty_struct *tty, struct file *file,
183 			unsigned int cmd, unsigned long arg);
184 static void cypress_set_termios(struct tty_struct *tty,
185 			struct usb_serial_port *port, struct ktermios *old);
186 static int  cypress_tiocmget(struct tty_struct *tty, struct file *file);
187 static int  cypress_tiocmset(struct tty_struct *tty, struct file *file,
188 			unsigned int set, unsigned int clear);
189 static int  cypress_chars_in_buffer(struct tty_struct *tty);
190 static void cypress_throttle(struct tty_struct *tty);
191 static void cypress_unthrottle(struct tty_struct *tty);
192 static void cypress_set_dead(struct usb_serial_port *port);
193 static void cypress_read_int_callback(struct urb *urb);
194 static void cypress_write_int_callback(struct urb *urb);
195 /* write buffer functions */
196 static struct cypress_buf *cypress_buf_alloc(unsigned int size);
197 static void cypress_buf_free(struct cypress_buf *cb);
198 static void cypress_buf_clear(struct cypress_buf *cb);
199 static unsigned int cypress_buf_data_avail(struct cypress_buf *cb);
200 static unsigned int cypress_buf_space_avail(struct cypress_buf *cb);
201 static unsigned int cypress_buf_put(struct cypress_buf *cb,
202 					const char *buf, unsigned int count);
203 static unsigned int cypress_buf_get(struct cypress_buf *cb,
204 					char *buf, unsigned int count);
205 
206 
207 static struct usb_serial_driver cypress_earthmate_device = {
208 	.driver = {
209 		.owner =		THIS_MODULE,
210 		.name =			"earthmate",
211 	},
212 	.description =			"DeLorme Earthmate USB",
213 	.usb_driver = 			&cypress_driver,
214 	.id_table =			id_table_earthmate,
215 	.num_ports =			1,
216 	.attach =			cypress_earthmate_startup,
217 	.release =			cypress_release,
218 	.open =				cypress_open,
219 	.close =			cypress_close,
220 	.dtr_rts =			cypress_dtr_rts,
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 	.release =			cypress_release,
245 	.open =				cypress_open,
246 	.close =			cypress_close,
247 	.dtr_rts =			cypress_dtr_rts,
248 	.write =			cypress_write,
249 	.write_room =			cypress_write_room,
250 	.ioctl =			cypress_ioctl,
251 	.set_termios =			cypress_set_termios,
252 	.tiocmget =			cypress_tiocmget,
253 	.tiocmset =			cypress_tiocmset,
254 	.chars_in_buffer =		cypress_chars_in_buffer,
255 	.throttle =			cypress_throttle,
256 	.unthrottle =			cypress_unthrottle,
257 	.read_int_callback =		cypress_read_int_callback,
258 	.write_int_callback =		cypress_write_int_callback,
259 };
260 
261 static struct usb_serial_driver cypress_ca42v2_device = {
262 	.driver = {
263 		.owner =		THIS_MODULE,
264 		.name =			"nokiaca42v2",
265 	},
266 	.description =			"Nokia CA-42 V2 Adapter",
267 	.usb_driver = 			&cypress_driver,
268 	.id_table =			id_table_nokiaca42v2,
269 	.num_ports =			1,
270 	.attach =			cypress_ca42v2_startup,
271 	.release =			cypress_release,
272 	.open =				cypress_open,
273 	.close =			cypress_close,
274 	.dtr_rts =			cypress_dtr_rts,
275 	.write =			cypress_write,
276 	.write_room =			cypress_write_room,
277 	.ioctl =			cypress_ioctl,
278 	.set_termios =			cypress_set_termios,
279 	.tiocmget =			cypress_tiocmget,
280 	.tiocmset =			cypress_tiocmset,
281 	.chars_in_buffer =		cypress_chars_in_buffer,
282 	.throttle =			cypress_throttle,
283 	.unthrottle =			cypress_unthrottle,
284 	.read_int_callback =		cypress_read_int_callback,
285 	.write_int_callback =		cypress_write_int_callback,
286 };
287 
288 /*****************************************************************************
289  * Cypress serial helper functions
290  *****************************************************************************/
291 
292 
293 static int analyze_baud_rate(struct usb_serial_port *port, speed_t new_rate)
294 {
295 	struct cypress_private *priv;
296 	priv = usb_get_serial_port_data(port);
297 
298 	/*
299 	 * The general purpose firmware for the Cypress M8 allows for
300 	 * a maximum speed of 57600bps (I have no idea whether DeLorme
301 	 * chose to use the general purpose firmware or not), if you
302 	 * need to modify this speed setting for your own project
303 	 * please add your own chiptype and modify the code likewise.
304 	 * The Cypress HID->COM device will work successfully up to
305 	 * 115200bps (but the actual throughput is around 3kBps).
306 	 */
307 	if (port->serial->dev->speed == USB_SPEED_LOW) {
308 		/*
309 		 * Mike Isely <isely@pobox.com> 2-Feb-2008: The
310 		 * Cypress app note that describes this mechanism
311 		 * states the the low-speed part can't handle more
312 		 * than 800 bytes/sec, in which case 4800 baud is the
313 		 * safest speed for a part like that.
314 		 */
315 		if (new_rate > 4800) {
316 			dbg("%s - failed setting baud rate, device incapable "
317 			    "speed %d", __func__, new_rate);
318 			return -1;
319 		}
320 	}
321 	switch (priv->chiptype) {
322 	case CT_EARTHMATE:
323 		if (new_rate <= 600) {
324 			/* 300 and 600 baud rates are supported under
325 			 * the generic firmware, but are not used with
326 			 * NMEA and SiRF protocols */
327 			dbg("%s - failed setting baud rate, unsupported speed "
328 			    "of %d on Earthmate GPS", __func__, new_rate);
329 			return -1;
330 		}
331 		break;
332 	default:
333 		break;
334 	}
335 	return new_rate;
336 }
337 
338 
339 /* This function can either set or retrieve the current serial line settings */
340 static int cypress_serial_control(struct tty_struct *tty,
341 	struct usb_serial_port *port, speed_t baud_rate, int data_bits,
342 	int stop_bits, int parity_enable, int parity_type, int reset,
343 	int cypress_request_type)
344 {
345 	int new_baudrate = 0, retval = 0, tries = 0;
346 	struct cypress_private *priv;
347 	__u8 feature_buffer[5];
348 	unsigned long flags;
349 
350 	dbg("%s", __func__);
351 
352 	priv = usb_get_serial_port_data(port);
353 
354 	if (!priv->comm_is_ok)
355 		return -ENODEV;
356 
357 	switch (cypress_request_type) {
358 	case CYPRESS_SET_CONFIG:
359 		new_baudrate = priv->baud_rate;
360 		/* 0 means 'Hang up' so doesn't change the true bit rate */
361 		if (baud_rate == 0)
362 			new_baudrate = priv->baud_rate;
363 		/* Change of speed ? */
364 		else if (baud_rate != priv->baud_rate) {
365 			dbg("%s - baud rate is changing", __func__);
366 			retval = analyze_baud_rate(port, baud_rate);
367 			if (retval >=  0) {
368 				new_baudrate = retval;
369 				dbg("%s - New baud rate set to %d",
370 				    __func__, new_baudrate);
371 			}
372 		}
373 		dbg("%s - baud rate is being sent as %d",
374 					__func__, new_baudrate);
375 
376 		memset(feature_buffer, 0, sizeof(feature_buffer));
377 		/* fill the feature_buffer with new configuration */
378 		*((u_int32_t *)feature_buffer) = new_baudrate;
379 		feature_buffer[4] |= data_bits;   /* assign data bits in 2 bit space ( max 3 ) */
380 		/* 1 bit gap */
381 		feature_buffer[4] |= (stop_bits << 3);   /* assign stop bits in 1 bit space */
382 		feature_buffer[4] |= (parity_enable << 4);   /* assign parity flag in 1 bit space */
383 		feature_buffer[4] |= (parity_type << 5);   /* assign parity type in 1 bit space */
384 		/* 1 bit gap */
385 		feature_buffer[4] |= (reset << 7);   /* assign reset at end of byte, 1 bit space */
386 
387 		dbg("%s - device is being sent this feature report:",
388 								__func__);
389 		dbg("%s - %02X - %02X - %02X - %02X - %02X", __func__,
390 			feature_buffer[0], feature_buffer[1],
391 			feature_buffer[2], feature_buffer[3],
392 			feature_buffer[4]);
393 
394 		do {
395 			retval = usb_control_msg(port->serial->dev,
396 					usb_sndctrlpipe(port->serial->dev, 0),
397 					HID_REQ_SET_REPORT,
398 					USB_DIR_OUT | USB_RECIP_INTERFACE | USB_TYPE_CLASS,
399 					0x0300, 0, feature_buffer,
400 					sizeof(feature_buffer), 500);
401 
402 			if (tries++ >= 3)
403 				break;
404 
405 		} while (retval != sizeof(feature_buffer) &&
406 			 retval != -ENODEV);
407 
408 		if (retval != sizeof(feature_buffer)) {
409 			dev_err(&port->dev, "%s - failed sending serial "
410 				"line settings - %d\n", __func__, retval);
411 			cypress_set_dead(port);
412 		} else {
413 			spin_lock_irqsave(&priv->lock, flags);
414 			priv->baud_rate = new_baudrate;
415 			priv->current_config = feature_buffer[4];
416 			spin_unlock_irqrestore(&priv->lock, flags);
417 			/* If we asked for a speed change encode it */
418 			if (baud_rate)
419 				tty_encode_baud_rate(tty,
420 					new_baudrate, new_baudrate);
421 		}
422 	break;
423 	case CYPRESS_GET_CONFIG:
424 		if (priv->get_cfg_unsafe) {
425 			/* Not implemented for this device,
426 			   and if we try to do it we're likely
427 			   to crash the hardware. */
428 			return -ENOTTY;
429 		}
430 		dbg("%s - retreiving serial line settings", __func__);
431 		/* set initial values in feature buffer */
432 		memset(feature_buffer, 0, sizeof(feature_buffer));
433 
434 		do {
435 			retval = usb_control_msg(port->serial->dev,
436 					usb_rcvctrlpipe(port->serial->dev, 0),
437 					HID_REQ_GET_REPORT,
438 					USB_DIR_IN | USB_RECIP_INTERFACE | USB_TYPE_CLASS,
439 					0x0300, 0, feature_buffer,
440 					sizeof(feature_buffer), 500);
441 
442 			if (tries++ >= 3)
443 				break;
444 		} while (retval != sizeof(feature_buffer)
445 						&& retval != -ENODEV);
446 
447 		if (retval != sizeof(feature_buffer)) {
448 			dev_err(&port->dev, "%s - failed to retrieve serial "
449 				"line settings - %d\n", __func__, retval);
450 			cypress_set_dead(port);
451 			return retval;
452 		} else {
453 			spin_lock_irqsave(&priv->lock, flags);
454 			/* store the config in one byte, and later
455 			   use bit masks to check values */
456 			priv->current_config = feature_buffer[4];
457 			priv->baud_rate = *((u_int32_t *)feature_buffer);
458 			spin_unlock_irqrestore(&priv->lock, flags);
459 		}
460 	}
461 	spin_lock_irqsave(&priv->lock, flags);
462 	++priv->cmd_count;
463 	spin_unlock_irqrestore(&priv->lock, flags);
464 
465 	return retval;
466 } /* cypress_serial_control */
467 
468 
469 static void cypress_set_dead(struct usb_serial_port *port)
470 {
471 	struct cypress_private *priv = usb_get_serial_port_data(port);
472 	unsigned long flags;
473 
474 	spin_lock_irqsave(&priv->lock, flags);
475 	if (!priv->comm_is_ok) {
476 		spin_unlock_irqrestore(&priv->lock, flags);
477 		return;
478 	}
479 	priv->comm_is_ok = 0;
480 	spin_unlock_irqrestore(&priv->lock, flags);
481 
482 	dev_err(&port->dev, "cypress_m8 suspending failing port %d - "
483 		"interval might be too short\n", port->number);
484 }
485 
486 
487 /*****************************************************************************
488  * Cypress serial driver functions
489  *****************************************************************************/
490 
491 
492 static int generic_startup(struct usb_serial *serial)
493 {
494 	struct cypress_private *priv;
495 	struct usb_serial_port *port = serial->port[0];
496 
497 	dbg("%s - port %d", __func__, port->number);
498 
499 	priv = kzalloc(sizeof(struct cypress_private), GFP_KERNEL);
500 	if (!priv)
501 		return -ENOMEM;
502 
503 	priv->comm_is_ok = !0;
504 	spin_lock_init(&priv->lock);
505 	priv->buf = cypress_buf_alloc(CYPRESS_BUF_SIZE);
506 	if (priv->buf == NULL) {
507 		kfree(priv);
508 		return -ENOMEM;
509 	}
510 	init_waitqueue_head(&priv->delta_msr_wait);
511 
512 	usb_reset_configuration(serial->dev);
513 
514 	priv->cmd_ctrl = 0;
515 	priv->line_control = 0;
516 	priv->termios_initialized = 0;
517 	priv->rx_flags = 0;
518 	/* Default packet format setting is determined by packet size.
519 	   Anything with a size larger then 9 must have a separate
520 	   count field since the 3 bit count field is otherwise too
521 	   small.  Otherwise we can use the slightly more compact
522 	   format.  This is in accordance with the cypress_m8 serial
523 	   converter app note. */
524 	if (port->interrupt_out_size > 9)
525 		priv->pkt_fmt = packet_format_1;
526 	else
527 		priv->pkt_fmt = packet_format_2;
528 
529 	if (interval > 0) {
530 		priv->write_urb_interval = interval;
531 		priv->read_urb_interval = interval;
532 		dbg("%s - port %d read & write intervals forced to %d",
533 		    __func__, port->number, interval);
534 	} else {
535 		priv->write_urb_interval = port->interrupt_out_urb->interval;
536 		priv->read_urb_interval = port->interrupt_in_urb->interval;
537 		dbg("%s - port %d intervals: read=%d write=%d",
538 		    __func__, port->number,
539 		    priv->read_urb_interval, priv->write_urb_interval);
540 	}
541 	usb_set_serial_port_data(port, priv);
542 
543 	return 0;
544 }
545 
546 
547 static int cypress_earthmate_startup(struct usb_serial *serial)
548 {
549 	struct cypress_private *priv;
550 	struct usb_serial_port *port = serial->port[0];
551 
552 	dbg("%s", __func__);
553 
554 	if (generic_startup(serial)) {
555 		dbg("%s - Failed setting up port %d", __func__,
556 				port->number);
557 		return 1;
558 	}
559 
560 	priv = usb_get_serial_port_data(port);
561 	priv->chiptype = CT_EARTHMATE;
562 	/* All Earthmate devices use the separated-count packet
563 	   format!  Idiotic. */
564 	priv->pkt_fmt = packet_format_1;
565 	if (serial->dev->descriptor.idProduct !=
566 				cpu_to_le16(PRODUCT_ID_EARTHMATEUSB)) {
567 		/* The old original USB Earthmate seemed able to
568 		   handle GET_CONFIG requests; everything they've
569 		   produced since that time crashes if this command is
570 		   attempted :-( */
571 		dbg("%s - Marking this device as unsafe for GET_CONFIG "
572 		    "commands", __func__);
573 		priv->get_cfg_unsafe = !0;
574 	}
575 
576 	return 0;
577 } /* cypress_earthmate_startup */
578 
579 
580 static int cypress_hidcom_startup(struct usb_serial *serial)
581 {
582 	struct cypress_private *priv;
583 
584 	dbg("%s", __func__);
585 
586 	if (generic_startup(serial)) {
587 		dbg("%s - Failed setting up port %d", __func__,
588 				serial->port[0]->number);
589 		return 1;
590 	}
591 
592 	priv = usb_get_serial_port_data(serial->port[0]);
593 	priv->chiptype = CT_CYPHIDCOM;
594 
595 	return 0;
596 } /* cypress_hidcom_startup */
597 
598 
599 static int cypress_ca42v2_startup(struct usb_serial *serial)
600 {
601 	struct cypress_private *priv;
602 
603 	dbg("%s", __func__);
604 
605 	if (generic_startup(serial)) {
606 		dbg("%s - Failed setting up port %d", __func__,
607 				serial->port[0]->number);
608 		return 1;
609 	}
610 
611 	priv = usb_get_serial_port_data(serial->port[0]);
612 	priv->chiptype = CT_CA42V2;
613 
614 	return 0;
615 } /* cypress_ca42v2_startup */
616 
617 
618 static void cypress_release(struct usb_serial *serial)
619 {
620 	struct cypress_private *priv;
621 
622 	dbg("%s - port %d", __func__, serial->port[0]->number);
623 
624 	/* all open ports are closed at this point */
625 
626 	priv = usb_get_serial_port_data(serial->port[0]);
627 
628 	if (priv) {
629 		cypress_buf_free(priv->buf);
630 		kfree(priv);
631 	}
632 }
633 
634 
635 static int cypress_open(struct tty_struct *tty, struct usb_serial_port *port)
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 	/* Set termios */
660 	cypress_send(port);
661 
662 	if (tty)
663 		cypress_set_termios(tty, port, &priv->tmp_termios);
664 
665 	/* setup the port and start reading from the device */
666 	if (!port->interrupt_in_urb) {
667 		dev_err(&port->dev, "%s - interrupt_in_urb is empty!\n",
668 			__func__);
669 		return -1;
670 	}
671 
672 	usb_fill_int_urb(port->interrupt_in_urb, serial->dev,
673 		usb_rcvintpipe(serial->dev, port->interrupt_in_endpointAddress),
674 		port->interrupt_in_urb->transfer_buffer,
675 		port->interrupt_in_urb->transfer_buffer_length,
676 		cypress_read_int_callback, port, priv->read_urb_interval);
677 	result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
678 
679 	if (result) {
680 		dev_err(&port->dev,
681 			"%s - failed submitting read urb, error %d\n",
682 							__func__, result);
683 		cypress_set_dead(port);
684 	}
685 	port->port.drain_delay = 256;
686 	return result;
687 } /* cypress_open */
688 
689 static void cypress_dtr_rts(struct usb_serial_port *port, int on)
690 {
691 	struct cypress_private *priv = usb_get_serial_port_data(port);
692 	/* drop dtr and rts */
693 	priv = usb_get_serial_port_data(port);
694 	spin_lock_irq(&priv->lock);
695 	if (on == 0)
696 		priv->line_control = 0;
697 	else
698 		priv->line_control = CONTROL_DTR | CONTROL_RTS;
699 	priv->cmd_ctrl = 1;
700 	spin_unlock_irq(&priv->lock);
701 	cypress_write(NULL, port, NULL, 0);
702 }
703 
704 static void cypress_close(struct usb_serial_port *port)
705 {
706 	struct cypress_private *priv = usb_get_serial_port_data(port);
707 
708 	dbg("%s - port %d", __func__, port->number);
709 
710 	/* writing is potentially harmful, lock must be taken */
711 	mutex_lock(&port->serial->disc_mutex);
712 	if (port->serial->disconnected) {
713 		mutex_unlock(&port->serial->disc_mutex);
714 		return;
715 	}
716 	cypress_buf_clear(priv->buf);
717 	dbg("%s - stopping urbs", __func__);
718 	usb_kill_urb(port->interrupt_in_urb);
719 	usb_kill_urb(port->interrupt_out_urb);
720 
721 
722 	if (stats)
723 		dev_info(&port->dev, "Statistics: %d Bytes In | %d Bytes Out | %d Commands Issued\n",
724 			priv->bytes_in, priv->bytes_out, priv->cmd_count);
725 	mutex_unlock(&port->serial->disc_mutex);
726 } /* cypress_close */
727 
728 
729 static int cypress_write(struct tty_struct *tty, struct usb_serial_port *port,
730 					const unsigned char *buf, int count)
731 {
732 	struct cypress_private *priv = usb_get_serial_port_data(port);
733 	unsigned long flags;
734 
735 	dbg("%s - port %d, %d bytes", __func__, port->number, count);
736 
737 	/* line control commands, which need to be executed immediately,
738 	   are not put into the buffer for obvious reasons.
739 	 */
740 	if (priv->cmd_ctrl) {
741 		count = 0;
742 		goto finish;
743 	}
744 
745 	if (!count)
746 		return count;
747 
748 	spin_lock_irqsave(&priv->lock, flags);
749 	count = cypress_buf_put(priv->buf, buf, count);
750 	spin_unlock_irqrestore(&priv->lock, flags);
751 
752 finish:
753 	cypress_send(port);
754 
755 	return count;
756 } /* cypress_write */
757 
758 
759 static void cypress_send(struct usb_serial_port *port)
760 {
761 	int count = 0, result, offset, actual_size;
762 	struct cypress_private *priv = usb_get_serial_port_data(port);
763 	unsigned long flags;
764 
765 	if (!priv->comm_is_ok)
766 		return;
767 
768 	dbg("%s - port %d", __func__, port->number);
769 	dbg("%s - interrupt out size is %d", __func__,
770 						port->interrupt_out_size);
771 
772 	spin_lock_irqsave(&priv->lock, flags);
773 	if (priv->write_urb_in_use) {
774 		dbg("%s - can't write, urb in use", __func__);
775 		spin_unlock_irqrestore(&priv->lock, flags);
776 		return;
777 	}
778 	spin_unlock_irqrestore(&priv->lock, flags);
779 
780 	/* clear buffer */
781 	memset(port->interrupt_out_urb->transfer_buffer, 0,
782 						port->interrupt_out_size);
783 
784 	spin_lock_irqsave(&priv->lock, flags);
785 	switch (priv->pkt_fmt) {
786 	default:
787 	case packet_format_1:
788 		/* this is for the CY7C64013... */
789 		offset = 2;
790 		port->interrupt_out_buffer[0] = priv->line_control;
791 		break;
792 	case packet_format_2:
793 		/* this is for the CY7C63743... */
794 		offset = 1;
795 		port->interrupt_out_buffer[0] = priv->line_control;
796 		break;
797 	}
798 
799 	if (priv->line_control & CONTROL_RESET)
800 		priv->line_control &= ~CONTROL_RESET;
801 
802 	if (priv->cmd_ctrl) {
803 		priv->cmd_count++;
804 		dbg("%s - line control command being issued", __func__);
805 		spin_unlock_irqrestore(&priv->lock, flags);
806 		goto send;
807 	} else
808 		spin_unlock_irqrestore(&priv->lock, flags);
809 
810 	count = cypress_buf_get(priv->buf, &port->interrupt_out_buffer[offset],
811 				port->interrupt_out_size-offset);
812 
813 	if (count == 0)
814 		return;
815 
816 	switch (priv->pkt_fmt) {
817 	default:
818 	case packet_format_1:
819 		port->interrupt_out_buffer[1] = count;
820 		break;
821 	case packet_format_2:
822 		port->interrupt_out_buffer[0] |= count;
823 	}
824 
825 	dbg("%s - count is %d", __func__, count);
826 
827 send:
828 	spin_lock_irqsave(&priv->lock, flags);
829 	priv->write_urb_in_use = 1;
830 	spin_unlock_irqrestore(&priv->lock, flags);
831 
832 	if (priv->cmd_ctrl)
833 		actual_size = 1;
834 	else
835 		actual_size = count +
836 			      (priv->pkt_fmt == packet_format_1 ? 2 : 1);
837 
838 	usb_serial_debug_data(debug, &port->dev, __func__,
839 		port->interrupt_out_size,
840 		port->interrupt_out_urb->transfer_buffer);
841 
842 	usb_fill_int_urb(port->interrupt_out_urb, port->serial->dev,
843 		usb_sndintpipe(port->serial->dev, port->interrupt_out_endpointAddress),
844 		port->interrupt_out_buffer, port->interrupt_out_size,
845 		cypress_write_int_callback, port, priv->write_urb_interval);
846 	result = usb_submit_urb(port->interrupt_out_urb, GFP_ATOMIC);
847 	if (result) {
848 		dev_err(&port->dev,
849 				"%s - failed submitting write urb, error %d\n",
850 							__func__, result);
851 		priv->write_urb_in_use = 0;
852 		cypress_set_dead(port);
853 	}
854 
855 	spin_lock_irqsave(&priv->lock, flags);
856 	if (priv->cmd_ctrl)
857 		priv->cmd_ctrl = 0;
858 
859 	/* do not count the line control and size bytes */
860 	priv->bytes_out += count;
861 	spin_unlock_irqrestore(&priv->lock, flags);
862 
863 	usb_serial_port_softint(port);
864 } /* cypress_send */
865 
866 
867 /* returns how much space is available in the soft buffer */
868 static int cypress_write_room(struct tty_struct *tty)
869 {
870 	struct usb_serial_port *port = tty->driver_data;
871 	struct cypress_private *priv = usb_get_serial_port_data(port);
872 	int room = 0;
873 	unsigned long flags;
874 
875 	dbg("%s - port %d", __func__, port->number);
876 
877 	spin_lock_irqsave(&priv->lock, flags);
878 	room = cypress_buf_space_avail(priv->buf);
879 	spin_unlock_irqrestore(&priv->lock, flags);
880 
881 	dbg("%s - returns %d", __func__, room);
882 	return room;
883 }
884 
885 
886 static int cypress_tiocmget(struct tty_struct *tty, struct file *file)
887 {
888 	struct usb_serial_port *port = tty->driver_data;
889 	struct cypress_private *priv = usb_get_serial_port_data(port);
890 	__u8 status, control;
891 	unsigned int result = 0;
892 	unsigned long flags;
893 
894 	dbg("%s - port %d", __func__, port->number);
895 
896 	spin_lock_irqsave(&priv->lock, flags);
897 	control = priv->line_control;
898 	status = priv->current_status;
899 	spin_unlock_irqrestore(&priv->lock, flags);
900 
901 	result = ((control & CONTROL_DTR)        ? TIOCM_DTR : 0)
902 		| ((control & CONTROL_RTS)       ? TIOCM_RTS : 0)
903 		| ((status & UART_CTS)        ? TIOCM_CTS : 0)
904 		| ((status & UART_DSR)        ? TIOCM_DSR : 0)
905 		| ((status & UART_RI)         ? TIOCM_RI  : 0)
906 		| ((status & UART_CD)         ? TIOCM_CD  : 0);
907 
908 	dbg("%s - result = %x", __func__, result);
909 
910 	return result;
911 }
912 
913 
914 static int cypress_tiocmset(struct tty_struct *tty, struct file *file,
915 			       unsigned int set, unsigned int clear)
916 {
917 	struct usb_serial_port *port = tty->driver_data;
918 	struct cypress_private *priv = usb_get_serial_port_data(port);
919 	unsigned long flags;
920 
921 	dbg("%s - port %d", __func__, port->number);
922 
923 	spin_lock_irqsave(&priv->lock, flags);
924 	if (set & TIOCM_RTS)
925 		priv->line_control |= CONTROL_RTS;
926 	if (set & TIOCM_DTR)
927 		priv->line_control |= CONTROL_DTR;
928 	if (clear & TIOCM_RTS)
929 		priv->line_control &= ~CONTROL_RTS;
930 	if (clear & TIOCM_DTR)
931 		priv->line_control &= ~CONTROL_DTR;
932 	priv->cmd_ctrl = 1;
933 	spin_unlock_irqrestore(&priv->lock, flags);
934 
935 	return cypress_write(tty, port, NULL, 0);
936 }
937 
938 
939 static int cypress_ioctl(struct tty_struct *tty, struct file *file,
940 					unsigned int cmd, unsigned long arg)
941 {
942 	struct usb_serial_port *port = tty->driver_data;
943 	struct cypress_private *priv = usb_get_serial_port_data(port);
944 
945 	dbg("%s - port %d, cmd 0x%.4x", __func__, port->number, cmd);
946 
947 	switch (cmd) {
948 	/* This code comes from drivers/char/serial.c and ftdi_sio.c */
949 	case TIOCMIWAIT:
950 		while (priv != NULL) {
951 			interruptible_sleep_on(&priv->delta_msr_wait);
952 			/* see if a signal did it */
953 			if (signal_pending(current))
954 				return -ERESTARTSYS;
955 			else {
956 				char diff = priv->diff_status;
957 				if (diff == 0)
958 					return -EIO; /* no change => error */
959 
960 				/* consume all events */
961 				priv->diff_status = 0;
962 
963 				/* return 0 if caller wanted to know about
964 				   these bits */
965 				if (((arg & TIOCM_RNG) && (diff & UART_RI)) ||
966 				    ((arg & TIOCM_DSR) && (diff & UART_DSR)) ||
967 				    ((arg & TIOCM_CD) && (diff & UART_CD)) ||
968 				    ((arg & TIOCM_CTS) && (diff & UART_CTS)))
969 					return 0;
970 				/* otherwise caller can't care less about what
971 				 * happened, and so we continue to wait for
972 				 * more events.
973 				 */
974 			}
975 		}
976 		return 0;
977 	default:
978 		break;
979 	}
980 	dbg("%s - arg not supported - it was 0x%04x - check include/asm/ioctls.h", __func__, cmd);
981 	return -ENOIOCTLCMD;
982 } /* cypress_ioctl */
983 
984 
985 static void cypress_set_termios(struct tty_struct *tty,
986 	struct usb_serial_port *port, struct ktermios *old_termios)
987 {
988 	struct cypress_private *priv = usb_get_serial_port_data(port);
989 	int data_bits, stop_bits, parity_type, parity_enable;
990 	unsigned cflag, iflag;
991 	unsigned long flags;
992 	__u8 oldlines;
993 	int linechange = 0;
994 
995 	dbg("%s - port %d", __func__, port->number);
996 
997 	spin_lock_irqsave(&priv->lock, flags);
998 	/* We can't clean this one up as we don't know the device type
999 	   early enough */
1000 	if (!priv->termios_initialized) {
1001 		if (priv->chiptype == CT_EARTHMATE) {
1002 			*(tty->termios) = tty_std_termios;
1003 			tty->termios->c_cflag = B4800 | CS8 | CREAD | HUPCL |
1004 				CLOCAL;
1005 			tty->termios->c_ispeed = 4800;
1006 			tty->termios->c_ospeed = 4800;
1007 		} else if (priv->chiptype == CT_CYPHIDCOM) {
1008 			*(tty->termios) = tty_std_termios;
1009 			tty->termios->c_cflag = B9600 | CS8 | CREAD | HUPCL |
1010 				CLOCAL;
1011 			tty->termios->c_ispeed = 9600;
1012 			tty->termios->c_ospeed = 9600;
1013 		} else if (priv->chiptype == CT_CA42V2) {
1014 			*(tty->termios) = tty_std_termios;
1015 			tty->termios->c_cflag = B9600 | CS8 | CREAD | HUPCL |
1016 				CLOCAL;
1017 			tty->termios->c_ispeed = 9600;
1018 			tty->termios->c_ospeed = 9600;
1019 		}
1020 		priv->termios_initialized = 1;
1021 	}
1022 	spin_unlock_irqrestore(&priv->lock, flags);
1023 
1024 	/* Unsupported features need clearing */
1025 	tty->termios->c_cflag &= ~(CMSPAR|CRTSCTS);
1026 
1027 	cflag = tty->termios->c_cflag;
1028 	iflag = tty->termios->c_iflag;
1029 
1030 	/* check if there are new settings */
1031 	if (old_termios) {
1032 		spin_lock_irqsave(&priv->lock, flags);
1033 		priv->tmp_termios = *(tty->termios);
1034 		spin_unlock_irqrestore(&priv->lock, flags);
1035 	}
1036 
1037 	/* set number of data bits, parity, stop bits */
1038 	/* when parity is disabled the parity type bit is ignored */
1039 
1040 	/* 1 means 2 stop bits, 0 means 1 stop bit */
1041 	stop_bits = cflag & CSTOPB ? 1 : 0;
1042 
1043 	if (cflag & PARENB) {
1044 		parity_enable = 1;
1045 		/* 1 means odd parity, 0 means even parity */
1046 		parity_type = cflag & PARODD ? 1 : 0;
1047 	} else
1048 		parity_enable = parity_type = 0;
1049 
1050 	switch (cflag & CSIZE) {
1051 	case CS5:
1052 		data_bits = 0;
1053 		break;
1054 	case CS6:
1055 		data_bits = 1;
1056 		break;
1057 	case CS7:
1058 		data_bits = 2;
1059 		break;
1060 	case CS8:
1061 		data_bits = 3;
1062 		break;
1063 	default:
1064 		dev_err(&port->dev, "%s - CSIZE was set, but not CS5-CS8\n",
1065 			__func__);
1066 		data_bits = 3;
1067 	}
1068 	spin_lock_irqsave(&priv->lock, flags);
1069 	oldlines = priv->line_control;
1070 	if ((cflag & CBAUD) == B0) {
1071 		/* drop dtr and rts */
1072 		dbg("%s - dropping the lines, baud rate 0bps", __func__);
1073 		priv->line_control &= ~(CONTROL_DTR | CONTROL_RTS);
1074 	} else
1075 		priv->line_control = (CONTROL_DTR | CONTROL_RTS);
1076 	spin_unlock_irqrestore(&priv->lock, flags);
1077 
1078 	dbg("%s - sending %d stop_bits, %d parity_enable, %d parity_type, "
1079 			"%d data_bits (+5)", __func__, stop_bits,
1080 			parity_enable, parity_type, data_bits);
1081 
1082 	cypress_serial_control(tty, port, tty_get_baud_rate(tty),
1083 			data_bits, stop_bits,
1084 			parity_enable, parity_type,
1085 			0, CYPRESS_SET_CONFIG);
1086 
1087 	/* we perform a CYPRESS_GET_CONFIG so that the current settings are
1088 	 * filled into the private structure this should confirm that all is
1089 	 * working if it returns what we just set */
1090 	cypress_serial_control(tty, port, 0, 0, 0, 0, 0, 0, CYPRESS_GET_CONFIG);
1091 
1092 	/* Here we can define custom tty settings for devices; the main tty
1093 	 * termios flag base comes from empeg.c */
1094 
1095 	spin_lock_irqsave(&priv->lock, flags);
1096 	if (priv->chiptype == CT_EARTHMATE && priv->baud_rate == 4800) {
1097 		dbg("Using custom termios settings for a baud rate of "
1098 				"4800bps.");
1099 		/* define custom termios settings for NMEA protocol */
1100 
1101 		tty->termios->c_iflag /* input modes - */
1102 			&= ~(IGNBRK  /* disable ignore break */
1103 			| BRKINT     /* disable break causes interrupt */
1104 			| PARMRK     /* disable mark parity errors */
1105 			| ISTRIP     /* disable clear high bit of input char */
1106 			| INLCR      /* disable translate NL to CR */
1107 			| IGNCR      /* disable ignore CR */
1108 			| ICRNL      /* disable translate CR to NL */
1109 			| IXON);     /* disable enable XON/XOFF flow control */
1110 
1111 		tty->termios->c_oflag /* output modes */
1112 			&= ~OPOST;    /* disable postprocess output char */
1113 
1114 		tty->termios->c_lflag /* line discipline modes */
1115 			&= ~(ECHO     /* disable echo input characters */
1116 			| ECHONL      /* disable echo new line */
1117 			| ICANON      /* disable erase, kill, werase, and rprnt
1118 					 special characters */
1119 			| ISIG        /* disable interrupt, quit, and suspend
1120 					 special characters */
1121 			| IEXTEN);    /* disable non-POSIX special characters */
1122 	} /* CT_CYPHIDCOM: Application should handle this for device */
1123 
1124 	linechange = (priv->line_control != oldlines);
1125 	spin_unlock_irqrestore(&priv->lock, flags);
1126 
1127 	/* if necessary, set lines */
1128 	if (linechange) {
1129 		priv->cmd_ctrl = 1;
1130 		cypress_write(tty, port, NULL, 0);
1131 	}
1132 } /* cypress_set_termios */
1133 
1134 
1135 /* returns amount of data still left in soft buffer */
1136 static int cypress_chars_in_buffer(struct tty_struct *tty)
1137 {
1138 	struct usb_serial_port *port = tty->driver_data;
1139 	struct cypress_private *priv = usb_get_serial_port_data(port);
1140 	int chars = 0;
1141 	unsigned long flags;
1142 
1143 	dbg("%s - port %d", __func__, port->number);
1144 
1145 	spin_lock_irqsave(&priv->lock, flags);
1146 	chars = cypress_buf_data_avail(priv->buf);
1147 	spin_unlock_irqrestore(&priv->lock, flags);
1148 
1149 	dbg("%s - returns %d", __func__, chars);
1150 	return chars;
1151 }
1152 
1153 
1154 static void cypress_throttle(struct tty_struct *tty)
1155 {
1156 	struct usb_serial_port *port = tty->driver_data;
1157 	struct cypress_private *priv = usb_get_serial_port_data(port);
1158 
1159 	dbg("%s - port %d", __func__, port->number);
1160 
1161 	spin_lock_irq(&priv->lock);
1162 	priv->rx_flags = THROTTLED;
1163 	spin_unlock_irq(&priv->lock);
1164 }
1165 
1166 
1167 static void cypress_unthrottle(struct tty_struct *tty)
1168 {
1169 	struct usb_serial_port *port = tty->driver_data;
1170 	struct cypress_private *priv = usb_get_serial_port_data(port);
1171 	int actually_throttled, result;
1172 
1173 	dbg("%s - port %d", __func__, port->number);
1174 
1175 	spin_lock_irq(&priv->lock);
1176 	actually_throttled = priv->rx_flags & ACTUALLY_THROTTLED;
1177 	priv->rx_flags = 0;
1178 	spin_unlock_irq(&priv->lock);
1179 
1180 	if (!priv->comm_is_ok)
1181 		return;
1182 
1183 	if (actually_throttled) {
1184 		port->interrupt_in_urb->dev = port->serial->dev;
1185 
1186 		result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
1187 		if (result) {
1188 			dev_err(&port->dev, "%s - failed submitting read urb, "
1189 					"error %d\n", __func__, result);
1190 			cypress_set_dead(port);
1191 		}
1192 	}
1193 }
1194 
1195 
1196 static void cypress_read_int_callback(struct urb *urb)
1197 {
1198 	struct usb_serial_port *port = urb->context;
1199 	struct cypress_private *priv = usb_get_serial_port_data(port);
1200 	struct tty_struct *tty;
1201 	unsigned char *data = urb->transfer_buffer;
1202 	unsigned long flags;
1203 	char tty_flag = TTY_NORMAL;
1204 	int havedata = 0;
1205 	int bytes = 0;
1206 	int result;
1207 	int i = 0;
1208 	int status = urb->status;
1209 
1210 	dbg("%s - port %d", __func__, port->number);
1211 
1212 	switch (status) {
1213 	case 0: /* success */
1214 		break;
1215 	case -ECONNRESET:
1216 	case -ENOENT:
1217 	case -ESHUTDOWN:
1218 		/* precursor to disconnect so just go away */
1219 		return;
1220 	case -EPIPE:
1221 		/* Can't call usb_clear_halt while in_interrupt */
1222 		/* FALLS THROUGH */
1223 	default:
1224 		/* something ugly is going on... */
1225 		dev_err(&urb->dev->dev,
1226 			"%s - unexpected nonzero read status received: %d\n",
1227 							__func__, status);
1228 		cypress_set_dead(port);
1229 		return;
1230 	}
1231 
1232 	spin_lock_irqsave(&priv->lock, flags);
1233 	if (priv->rx_flags & THROTTLED) {
1234 		dbg("%s - now throttling", __func__);
1235 		priv->rx_flags |= ACTUALLY_THROTTLED;
1236 		spin_unlock_irqrestore(&priv->lock, flags);
1237 		return;
1238 	}
1239 	spin_unlock_irqrestore(&priv->lock, flags);
1240 
1241 	tty = tty_port_tty_get(&port->port);
1242 	if (!tty) {
1243 		dbg("%s - bad tty pointer - exiting", __func__);
1244 		return;
1245 	}
1246 
1247 	spin_lock_irqsave(&priv->lock, flags);
1248 	result = urb->actual_length;
1249 	switch (priv->pkt_fmt) {
1250 	default:
1251 	case packet_format_1:
1252 		/* This is for the CY7C64013... */
1253 		priv->current_status = data[0] & 0xF8;
1254 		bytes = data[1] + 2;
1255 		i = 2;
1256 		if (bytes > 2)
1257 			havedata = 1;
1258 		break;
1259 	case packet_format_2:
1260 		/* This is for the CY7C63743... */
1261 		priv->current_status = data[0] & 0xF8;
1262 		bytes = (data[0] & 0x07) + 1;
1263 		i = 1;
1264 		if (bytes > 1)
1265 			havedata = 1;
1266 		break;
1267 	}
1268 	spin_unlock_irqrestore(&priv->lock, flags);
1269 	if (result < bytes) {
1270 		dbg("%s - wrong packet size - received %d bytes but packet "
1271 		    "said %d bytes", __func__, result, bytes);
1272 		goto continue_read;
1273 	}
1274 
1275 	usb_serial_debug_data(debug, &port->dev, __func__,
1276 						urb->actual_length, data);
1277 
1278 	spin_lock_irqsave(&priv->lock, flags);
1279 	/* check to see if status has changed */
1280 	if (priv->current_status != priv->prev_status) {
1281 		priv->diff_status |= priv->current_status ^
1282 			priv->prev_status;
1283 		wake_up_interruptible(&priv->delta_msr_wait);
1284 		priv->prev_status = priv->current_status;
1285 	}
1286 	spin_unlock_irqrestore(&priv->lock, flags);
1287 
1288 	/* hangup, as defined in acm.c... this might be a bad place for it
1289 	 * though */
1290 	if (tty && !(tty->termios->c_cflag & CLOCAL) &&
1291 			!(priv->current_status & UART_CD)) {
1292 		dbg("%s - calling hangup", __func__);
1293 		tty_hangup(tty);
1294 		goto continue_read;
1295 	}
1296 
1297 	/* There is one error bit... I'm assuming it is a parity error
1298 	 * indicator as the generic firmware will set this bit to 1 if a
1299 	 * parity error occurs.
1300 	 * I can not find reference to any other error events. */
1301 	spin_lock_irqsave(&priv->lock, flags);
1302 	if (priv->current_status & CYP_ERROR) {
1303 		spin_unlock_irqrestore(&priv->lock, flags);
1304 		tty_flag = TTY_PARITY;
1305 		dbg("%s - Parity Error detected", __func__);
1306 	} else
1307 		spin_unlock_irqrestore(&priv->lock, flags);
1308 
1309 	/* process read if there is data other than line status */
1310 	if (tty && (bytes > i)) {
1311 		bytes = tty_buffer_request_room(tty, bytes);
1312 		for (; i < bytes ; ++i) {
1313 			dbg("pushing byte number %d - %d - %c", i, data[i],
1314 					data[i]);
1315 			tty_insert_flip_char(tty, data[i], tty_flag);
1316 		}
1317 		tty_flip_buffer_push(tty);
1318 	}
1319 
1320 	spin_lock_irqsave(&priv->lock, flags);
1321 	/* control and status byte(s) are also counted */
1322 	priv->bytes_in += bytes;
1323 	spin_unlock_irqrestore(&priv->lock, flags);
1324 
1325 continue_read:
1326 	tty_kref_put(tty);
1327 
1328 	/* Continue trying to always read... unless the port has closed. */
1329 
1330 	if (port->port.count > 0 && priv->comm_is_ok) {
1331 		usb_fill_int_urb(port->interrupt_in_urb, port->serial->dev,
1332 				usb_rcvintpipe(port->serial->dev,
1333 					port->interrupt_in_endpointAddress),
1334 				port->interrupt_in_urb->transfer_buffer,
1335 				port->interrupt_in_urb->transfer_buffer_length,
1336 				cypress_read_int_callback, port,
1337 				priv->read_urb_interval);
1338 		result = usb_submit_urb(port->interrupt_in_urb, GFP_ATOMIC);
1339 		if (result) {
1340 			dev_err(&urb->dev->dev, "%s - failed resubmitting "
1341 					"read urb, error %d\n", __func__,
1342 					result);
1343 			cypress_set_dead(port);
1344 		}
1345 	}
1346 
1347 	return;
1348 } /* cypress_read_int_callback */
1349 
1350 
1351 static void cypress_write_int_callback(struct urb *urb)
1352 {
1353 	struct usb_serial_port *port = urb->context;
1354 	struct cypress_private *priv = usb_get_serial_port_data(port);
1355 	int result;
1356 	int status = urb->status;
1357 
1358 	dbg("%s - port %d", __func__, port->number);
1359 
1360 	switch (status) {
1361 	case 0:
1362 		/* success */
1363 		break;
1364 	case -ECONNRESET:
1365 	case -ENOENT:
1366 	case -ESHUTDOWN:
1367 		/* this urb is terminated, clean up */
1368 		dbg("%s - urb shutting down with status: %d",
1369 						__func__, status);
1370 		priv->write_urb_in_use = 0;
1371 		return;
1372 	case -EPIPE: /* no break needed; clear halt and resubmit */
1373 		if (!priv->comm_is_ok)
1374 			break;
1375 		usb_clear_halt(port->serial->dev, 0x02);
1376 		/* error in the urb, so we have to resubmit it */
1377 		dbg("%s - nonzero write bulk status received: %d",
1378 			__func__, status);
1379 		port->interrupt_out_urb->transfer_buffer_length = 1;
1380 		port->interrupt_out_urb->dev = port->serial->dev;
1381 		result = usb_submit_urb(port->interrupt_out_urb, GFP_ATOMIC);
1382 		if (!result)
1383 			return;
1384 		dev_err(&urb->dev->dev,
1385 			"%s - failed resubmitting write urb, error %d\n",
1386 							__func__, result);
1387 		cypress_set_dead(port);
1388 		break;
1389 	default:
1390 		dev_err(&urb->dev->dev,
1391 			 "%s - unexpected nonzero write status received: %d\n",
1392 							__func__, status);
1393 		cypress_set_dead(port);
1394 		break;
1395 	}
1396 	priv->write_urb_in_use = 0;
1397 
1398 	/* send any buffered data */
1399 	cypress_send(port);
1400 }
1401 
1402 
1403 /*****************************************************************************
1404  * Write buffer functions - buffering code from pl2303 used
1405  *****************************************************************************/
1406 
1407 /*
1408  * cypress_buf_alloc
1409  *
1410  * Allocate a circular buffer and all associated memory.
1411  */
1412 
1413 static struct cypress_buf *cypress_buf_alloc(unsigned int size)
1414 {
1415 
1416 	struct cypress_buf *cb;
1417 
1418 
1419 	if (size == 0)
1420 		return NULL;
1421 
1422 	cb = kmalloc(sizeof(struct cypress_buf), GFP_KERNEL);
1423 	if (cb == NULL)
1424 		return NULL;
1425 
1426 	cb->buf_buf = kmalloc(size, GFP_KERNEL);
1427 	if (cb->buf_buf == NULL) {
1428 		kfree(cb);
1429 		return NULL;
1430 	}
1431 
1432 	cb->buf_size = size;
1433 	cb->buf_get = cb->buf_put = cb->buf_buf;
1434 
1435 	return cb;
1436 
1437 }
1438 
1439 
1440 /*
1441  * cypress_buf_free
1442  *
1443  * Free the buffer and all associated memory.
1444  */
1445 
1446 static void cypress_buf_free(struct cypress_buf *cb)
1447 {
1448 	if (cb) {
1449 		kfree(cb->buf_buf);
1450 		kfree(cb);
1451 	}
1452 }
1453 
1454 
1455 /*
1456  * cypress_buf_clear
1457  *
1458  * Clear out all data in the circular buffer.
1459  */
1460 
1461 static void cypress_buf_clear(struct cypress_buf *cb)
1462 {
1463 	if (cb != NULL)
1464 		cb->buf_get = cb->buf_put;
1465 		/* equivalent to a get of all data available */
1466 }
1467 
1468 
1469 /*
1470  * cypress_buf_data_avail
1471  *
1472  * Return the number of bytes of data available in the circular
1473  * buffer.
1474  */
1475 
1476 static unsigned int cypress_buf_data_avail(struct cypress_buf *cb)
1477 {
1478 	if (cb != NULL)
1479 		return (cb->buf_size + cb->buf_put - cb->buf_get)
1480 							% cb->buf_size;
1481 	else
1482 		return 0;
1483 }
1484 
1485 
1486 /*
1487  * cypress_buf_space_avail
1488  *
1489  * Return the number of bytes of space available in the circular
1490  * buffer.
1491  */
1492 
1493 static unsigned int cypress_buf_space_avail(struct cypress_buf *cb)
1494 {
1495 	if (cb != NULL)
1496 		return (cb->buf_size + cb->buf_get - cb->buf_put - 1)
1497 							% cb->buf_size;
1498 	else
1499 		return 0;
1500 }
1501 
1502 
1503 /*
1504  * cypress_buf_put
1505  *
1506  * Copy data data from a user buffer and put it into the circular buffer.
1507  * Restrict to the amount of space available.
1508  *
1509  * Return the number of bytes copied.
1510  */
1511 
1512 static unsigned int cypress_buf_put(struct cypress_buf *cb, const char *buf,
1513 	unsigned int count)
1514 {
1515 
1516 	unsigned int len;
1517 
1518 
1519 	if (cb == NULL)
1520 		return 0;
1521 
1522 	len  = cypress_buf_space_avail(cb);
1523 	if (count > len)
1524 		count = len;
1525 
1526 	if (count == 0)
1527 		return 0;
1528 
1529 	len = cb->buf_buf + cb->buf_size - cb->buf_put;
1530 	if (count > len) {
1531 		memcpy(cb->buf_put, buf, len);
1532 		memcpy(cb->buf_buf, buf+len, count - len);
1533 		cb->buf_put = cb->buf_buf + count - len;
1534 	} else {
1535 		memcpy(cb->buf_put, buf, count);
1536 		if (count < len)
1537 			cb->buf_put += count;
1538 		else /* count == len */
1539 			cb->buf_put = cb->buf_buf;
1540 	}
1541 
1542 	return count;
1543 
1544 }
1545 
1546 
1547 /*
1548  * cypress_buf_get
1549  *
1550  * Get data from the circular buffer and copy to the given buffer.
1551  * Restrict to the amount of data available.
1552  *
1553  * Return the number of bytes copied.
1554  */
1555 
1556 static unsigned int cypress_buf_get(struct cypress_buf *cb, char *buf,
1557 	unsigned int count)
1558 {
1559 
1560 	unsigned int len;
1561 
1562 
1563 	if (cb == NULL)
1564 		return 0;
1565 
1566 	len = cypress_buf_data_avail(cb);
1567 	if (count > len)
1568 		count = len;
1569 
1570 	if (count == 0)
1571 		return 0;
1572 
1573 	len = cb->buf_buf + cb->buf_size - cb->buf_get;
1574 	if (count > len) {
1575 		memcpy(buf, cb->buf_get, len);
1576 		memcpy(buf+len, cb->buf_buf, count - len);
1577 		cb->buf_get = cb->buf_buf + count - len;
1578 	} else {
1579 		memcpy(buf, cb->buf_get, count);
1580 		if (count < len)
1581 			cb->buf_get += count;
1582 		else /* count == len */
1583 			cb->buf_get = cb->buf_buf;
1584 	}
1585 
1586 	return count;
1587 
1588 }
1589 
1590 /*****************************************************************************
1591  * Module functions
1592  *****************************************************************************/
1593 
1594 static int __init cypress_init(void)
1595 {
1596 	int retval;
1597 
1598 	dbg("%s", __func__);
1599 
1600 	retval = usb_serial_register(&cypress_earthmate_device);
1601 	if (retval)
1602 		goto failed_em_register;
1603 	retval = usb_serial_register(&cypress_hidcom_device);
1604 	if (retval)
1605 		goto failed_hidcom_register;
1606 	retval = usb_serial_register(&cypress_ca42v2_device);
1607 	if (retval)
1608 		goto failed_ca42v2_register;
1609 	retval = usb_register(&cypress_driver);
1610 	if (retval)
1611 		goto failed_usb_register;
1612 
1613 	printk(KERN_INFO KBUILD_MODNAME ": " DRIVER_VERSION ":"
1614 	       DRIVER_DESC "\n");
1615 	return 0;
1616 
1617 failed_usb_register:
1618 	usb_serial_deregister(&cypress_ca42v2_device);
1619 failed_ca42v2_register:
1620 	usb_serial_deregister(&cypress_hidcom_device);
1621 failed_hidcom_register:
1622 	usb_serial_deregister(&cypress_earthmate_device);
1623 failed_em_register:
1624 	return retval;
1625 }
1626 
1627 
1628 static void __exit cypress_exit(void)
1629 {
1630 	dbg("%s", __func__);
1631 
1632 	usb_deregister(&cypress_driver);
1633 	usb_serial_deregister(&cypress_earthmate_device);
1634 	usb_serial_deregister(&cypress_hidcom_device);
1635 	usb_serial_deregister(&cypress_ca42v2_device);
1636 }
1637 
1638 
1639 module_init(cypress_init);
1640 module_exit(cypress_exit);
1641 
1642 MODULE_AUTHOR(DRIVER_AUTHOR);
1643 MODULE_DESCRIPTION(DRIVER_DESC);
1644 MODULE_VERSION(DRIVER_VERSION);
1645 MODULE_LICENSE("GPL");
1646 
1647 module_param(debug, bool, S_IRUGO | S_IWUSR);
1648 MODULE_PARM_DESC(debug, "Debug enabled or not");
1649 module_param(stats, bool, S_IRUGO | S_IWUSR);
1650 MODULE_PARM_DESC(stats, "Enable statistics or not");
1651 module_param(interval, int, S_IRUGO | S_IWUSR);
1652 MODULE_PARM_DESC(interval, "Overrides interrupt interval");
1653