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
21/* Thanks to Neil Whelchel for writing the first cypress m8 implementation
22   for linux. */
23/* Thanks to cypress for providing references for the hid reports. */
24/* Thanks to Jiang Zhang for providing links and for general help. */
25/* Code originates and was built up from ftdi_sio, belkin, pl2303 and others.*/
26
27
28#include <linux/kernel.h>
29#include <linux/errno.h>
30#include <linux/slab.h>
31#include <linux/tty.h>
32#include <linux/tty_driver.h>
33#include <linux/tty_flip.h>
34#include <linux/module.h>
35#include <linux/moduleparam.h>
36#include <linux/spinlock.h>
37#include <linux/usb.h>
38#include <linux/usb/serial.h>
39#include <linux/serial.h>
40#include <linux/kfifo.h>
41#include <linux/delay.h>
42#include <linux/uaccess.h>
43#include <asm/unaligned.h>
44
45#include "cypress_m8.h"
46
47
48static bool stats;
49static int interval;
50static bool unstable_bauds;
51
52#define DRIVER_AUTHOR "Lonnie Mendez <dignome@gmail.com>, Neil Whelchel <koyama@firstlight.net>"
53#define DRIVER_DESC "Cypress USB to Serial Driver"
54
55/* write buffer size defines */
56#define CYPRESS_BUF_SIZE	1024
57
58static const struct usb_device_id id_table_earthmate[] = {
59	{ USB_DEVICE(VENDOR_ID_DELORME, PRODUCT_ID_EARTHMATEUSB) },
60	{ USB_DEVICE(VENDOR_ID_DELORME, PRODUCT_ID_EARTHMATEUSB_LT20) },
61	{ }						/* Terminating entry */
62};
63
64static const struct usb_device_id id_table_cyphidcomrs232[] = {
65	{ USB_DEVICE(VENDOR_ID_CYPRESS, PRODUCT_ID_CYPHIDCOM) },
66	{ USB_DEVICE(VENDOR_ID_POWERCOM, PRODUCT_ID_UPS) },
67	{ USB_DEVICE(VENDOR_ID_FRWD, PRODUCT_ID_CYPHIDCOM_FRWD) },
68	{ }						/* Terminating entry */
69};
70
71static const struct usb_device_id id_table_nokiaca42v2[] = {
72	{ USB_DEVICE(VENDOR_ID_DAZZLE, PRODUCT_ID_CA42) },
73	{ }						/* Terminating entry */
74};
75
76static const struct usb_device_id id_table_combined[] = {
77	{ USB_DEVICE(VENDOR_ID_DELORME, PRODUCT_ID_EARTHMATEUSB) },
78	{ USB_DEVICE(VENDOR_ID_DELORME, PRODUCT_ID_EARTHMATEUSB_LT20) },
79	{ USB_DEVICE(VENDOR_ID_CYPRESS, PRODUCT_ID_CYPHIDCOM) },
80	{ USB_DEVICE(VENDOR_ID_POWERCOM, PRODUCT_ID_UPS) },
81	{ USB_DEVICE(VENDOR_ID_FRWD, PRODUCT_ID_CYPHIDCOM_FRWD) },
82	{ USB_DEVICE(VENDOR_ID_DAZZLE, PRODUCT_ID_CA42) },
83	{ }						/* Terminating entry */
84};
85
86MODULE_DEVICE_TABLE(usb, id_table_combined);
87
88enum packet_format {
89	packet_format_1,  /* b0:status, b1:payload count */
90	packet_format_2   /* b0[7:3]:status, b0[2:0]:payload count */
91};
92
93struct cypress_private {
94	spinlock_t lock;		   /* private lock */
95	int chiptype;			   /* identifier of device, for quirks/etc */
96	int bytes_in;			   /* used for statistics */
97	int bytes_out;			   /* used for statistics */
98	int cmd_count;			   /* used for statistics */
99	int cmd_ctrl;			   /* always set this to 1 before issuing a command */
100	struct kfifo write_fifo;	   /* write fifo */
101	int write_urb_in_use;		   /* write urb in use indicator */
102	int write_urb_interval;            /* interval to use for write urb */
103	int read_urb_interval;             /* interval to use for read urb */
104	int comm_is_ok;                    /* true if communication is (still) ok */
105	int termios_initialized;
106	__u8 line_control;	   	   /* holds dtr / rts value */
107	__u8 current_status;	   	   /* received from last read - info on dsr,cts,cd,ri,etc */
108	__u8 current_config;	   	   /* stores the current configuration byte */
109	__u8 rx_flags;			   /* throttling - used from whiteheat/ftdi_sio */
110	enum packet_format pkt_fmt;	   /* format to use for packet send / receive */
111	int get_cfg_unsafe;		   /* If true, the CYPRESS_GET_CONFIG is unsafe */
112	int baud_rate;			   /* stores current baud rate in
113					      integer form */
114	int isthrottled;		   /* if throttled, discard reads */
115	char prev_status;		   /* used for TIOCMIWAIT */
116	/* we pass a pointer to this as the argument sent to
117	   cypress_set_termios old_termios */
118	struct ktermios tmp_termios; 	   /* stores the old termios settings */
119};
120
121/* function prototypes for the Cypress USB to serial device */
122static int  cypress_earthmate_port_probe(struct usb_serial_port *port);
123static int  cypress_hidcom_port_probe(struct usb_serial_port *port);
124static int  cypress_ca42v2_port_probe(struct usb_serial_port *port);
125static int  cypress_port_remove(struct usb_serial_port *port);
126static int  cypress_open(struct tty_struct *tty, struct usb_serial_port *port);
127static void cypress_close(struct usb_serial_port *port);
128static void cypress_dtr_rts(struct usb_serial_port *port, int on);
129static int  cypress_write(struct tty_struct *tty, struct usb_serial_port *port,
130			const unsigned char *buf, int count);
131static void cypress_send(struct usb_serial_port *port);
132static int  cypress_write_room(struct tty_struct *tty);
133static void cypress_set_termios(struct tty_struct *tty,
134			struct usb_serial_port *port, struct ktermios *old);
135static int  cypress_tiocmget(struct tty_struct *tty);
136static int  cypress_tiocmset(struct tty_struct *tty,
137			unsigned int set, unsigned int clear);
138static int  cypress_chars_in_buffer(struct tty_struct *tty);
139static void cypress_throttle(struct tty_struct *tty);
140static void cypress_unthrottle(struct tty_struct *tty);
141static void cypress_set_dead(struct usb_serial_port *port);
142static void cypress_read_int_callback(struct urb *urb);
143static void cypress_write_int_callback(struct urb *urb);
144
145static struct usb_serial_driver cypress_earthmate_device = {
146	.driver = {
147		.owner =		THIS_MODULE,
148		.name =			"earthmate",
149	},
150	.description =			"DeLorme Earthmate USB",
151	.id_table =			id_table_earthmate,
152	.num_ports =			1,
153	.port_probe =			cypress_earthmate_port_probe,
154	.port_remove =			cypress_port_remove,
155	.open =				cypress_open,
156	.close =			cypress_close,
157	.dtr_rts =			cypress_dtr_rts,
158	.write =			cypress_write,
159	.write_room =			cypress_write_room,
160	.set_termios =			cypress_set_termios,
161	.tiocmget =			cypress_tiocmget,
162	.tiocmset =			cypress_tiocmset,
163	.tiocmiwait =			usb_serial_generic_tiocmiwait,
164	.chars_in_buffer =		cypress_chars_in_buffer,
165	.throttle =		 	cypress_throttle,
166	.unthrottle =			cypress_unthrottle,
167	.read_int_callback =		cypress_read_int_callback,
168	.write_int_callback =		cypress_write_int_callback,
169};
170
171static struct usb_serial_driver cypress_hidcom_device = {
172	.driver = {
173		.owner =		THIS_MODULE,
174		.name =			"cyphidcom",
175	},
176	.description =			"HID->COM RS232 Adapter",
177	.id_table =			id_table_cyphidcomrs232,
178	.num_ports =			1,
179	.port_probe =			cypress_hidcom_port_probe,
180	.port_remove =			cypress_port_remove,
181	.open =				cypress_open,
182	.close =			cypress_close,
183	.dtr_rts =			cypress_dtr_rts,
184	.write =			cypress_write,
185	.write_room =			cypress_write_room,
186	.set_termios =			cypress_set_termios,
187	.tiocmget =			cypress_tiocmget,
188	.tiocmset =			cypress_tiocmset,
189	.tiocmiwait =			usb_serial_generic_tiocmiwait,
190	.chars_in_buffer =		cypress_chars_in_buffer,
191	.throttle =			cypress_throttle,
192	.unthrottle =			cypress_unthrottle,
193	.read_int_callback =		cypress_read_int_callback,
194	.write_int_callback =		cypress_write_int_callback,
195};
196
197static struct usb_serial_driver cypress_ca42v2_device = {
198	.driver = {
199		.owner =		THIS_MODULE,
200		.name =			"nokiaca42v2",
201	},
202	.description =			"Nokia CA-42 V2 Adapter",
203	.id_table =			id_table_nokiaca42v2,
204	.num_ports =			1,
205	.port_probe =			cypress_ca42v2_port_probe,
206	.port_remove =			cypress_port_remove,
207	.open =				cypress_open,
208	.close =			cypress_close,
209	.dtr_rts =			cypress_dtr_rts,
210	.write =			cypress_write,
211	.write_room =			cypress_write_room,
212	.set_termios =			cypress_set_termios,
213	.tiocmget =			cypress_tiocmget,
214	.tiocmset =			cypress_tiocmset,
215	.tiocmiwait =			usb_serial_generic_tiocmiwait,
216	.chars_in_buffer =		cypress_chars_in_buffer,
217	.throttle =			cypress_throttle,
218	.unthrottle =			cypress_unthrottle,
219	.read_int_callback =		cypress_read_int_callback,
220	.write_int_callback =		cypress_write_int_callback,
221};
222
223static struct usb_serial_driver * const serial_drivers[] = {
224	&cypress_earthmate_device, &cypress_hidcom_device,
225	&cypress_ca42v2_device, NULL
226};
227
228/*****************************************************************************
229 * Cypress serial helper functions
230 *****************************************************************************/
231
232/* FRWD Dongle hidcom needs to skip reset and speed checks */
233static inline bool is_frwd(struct usb_device *dev)
234{
235	return ((le16_to_cpu(dev->descriptor.idVendor) == VENDOR_ID_FRWD) &&
236		(le16_to_cpu(dev->descriptor.idProduct) == PRODUCT_ID_CYPHIDCOM_FRWD));
237}
238
239static int analyze_baud_rate(struct usb_serial_port *port, speed_t new_rate)
240{
241	struct cypress_private *priv;
242	priv = usb_get_serial_port_data(port);
243
244	if (unstable_bauds)
245		return new_rate;
246
247	/* FRWD Dongle uses 115200 bps */
248	if (is_frwd(port->serial->dev))
249		return new_rate;
250
251	/*
252	 * The general purpose firmware for the Cypress M8 allows for
253	 * a maximum speed of 57600bps (I have no idea whether DeLorme
254	 * chose to use the general purpose firmware or not), if you
255	 * need to modify this speed setting for your own project
256	 * please add your own chiptype and modify the code likewise.
257	 * The Cypress HID->COM device will work successfully up to
258	 * 115200bps (but the actual throughput is around 3kBps).
259	 */
260	if (port->serial->dev->speed == USB_SPEED_LOW) {
261		/*
262		 * Mike Isely <isely@pobox.com> 2-Feb-2008: The
263		 * Cypress app note that describes this mechanism
264		 * states the the low-speed part can't handle more
265		 * than 800 bytes/sec, in which case 4800 baud is the
266		 * safest speed for a part like that.
267		 */
268		if (new_rate > 4800) {
269			dev_dbg(&port->dev,
270				"%s - failed setting baud rate, device incapable speed %d\n",
271				__func__, new_rate);
272			return -1;
273		}
274	}
275	switch (priv->chiptype) {
276	case CT_EARTHMATE:
277		if (new_rate <= 600) {
278			/* 300 and 600 baud rates are supported under
279			 * the generic firmware, but are not used with
280			 * NMEA and SiRF protocols */
281			dev_dbg(&port->dev,
282				"%s - failed setting baud rate, unsupported speed of %d on Earthmate GPS\n",
283				__func__, new_rate);
284			return -1;
285		}
286		break;
287	default:
288		break;
289	}
290	return new_rate;
291}
292
293
294/* This function can either set or retrieve the current serial line settings */
295static int cypress_serial_control(struct tty_struct *tty,
296	struct usb_serial_port *port, speed_t baud_rate, int data_bits,
297	int stop_bits, int parity_enable, int parity_type, int reset,
298	int cypress_request_type)
299{
300	int new_baudrate = 0, retval = 0, tries = 0;
301	struct cypress_private *priv;
302	struct device *dev = &port->dev;
303	u8 *feature_buffer;
304	const unsigned int feature_len = 5;
305	unsigned long flags;
306
307	priv = usb_get_serial_port_data(port);
308
309	if (!priv->comm_is_ok)
310		return -ENODEV;
311
312	feature_buffer = kcalloc(feature_len, sizeof(u8), GFP_KERNEL);
313	if (!feature_buffer)
314		return -ENOMEM;
315
316	switch (cypress_request_type) {
317	case CYPRESS_SET_CONFIG:
318		/* 0 means 'Hang up' so doesn't change the true bit rate */
319		new_baudrate = priv->baud_rate;
320		if (baud_rate && baud_rate != priv->baud_rate) {
321			dev_dbg(dev, "%s - baud rate is changing\n", __func__);
322			retval = analyze_baud_rate(port, baud_rate);
323			if (retval >= 0) {
324				new_baudrate = retval;
325				dev_dbg(dev, "%s - New baud rate set to %d\n",
326					__func__, new_baudrate);
327			}
328		}
329		dev_dbg(dev, "%s - baud rate is being sent as %d\n", __func__,
330			new_baudrate);
331
332		/* fill the feature_buffer with new configuration */
333		put_unaligned_le32(new_baudrate, feature_buffer);
334		feature_buffer[4] |= data_bits;   /* assign data bits in 2 bit space ( max 3 ) */
335		/* 1 bit gap */
336		feature_buffer[4] |= (stop_bits << 3);   /* assign stop bits in 1 bit space */
337		feature_buffer[4] |= (parity_enable << 4);   /* assign parity flag in 1 bit space */
338		feature_buffer[4] |= (parity_type << 5);   /* assign parity type in 1 bit space */
339		/* 1 bit gap */
340		feature_buffer[4] |= (reset << 7);   /* assign reset at end of byte, 1 bit space */
341
342		dev_dbg(dev, "%s - device is being sent this feature report:\n", __func__);
343		dev_dbg(dev, "%s - %02X - %02X - %02X - %02X - %02X\n", __func__,
344			feature_buffer[0], feature_buffer[1],
345			feature_buffer[2], feature_buffer[3],
346			feature_buffer[4]);
347
348		do {
349			retval = usb_control_msg(port->serial->dev,
350					usb_sndctrlpipe(port->serial->dev, 0),
351					HID_REQ_SET_REPORT,
352					USB_DIR_OUT | USB_RECIP_INTERFACE | USB_TYPE_CLASS,
353					0x0300, 0, feature_buffer,
354					feature_len, 500);
355
356			if (tries++ >= 3)
357				break;
358
359		} while (retval != feature_len &&
360			 retval != -ENODEV);
361
362		if (retval != feature_len) {
363			dev_err(dev, "%s - failed sending serial line settings - %d\n",
364				__func__, retval);
365			cypress_set_dead(port);
366		} else {
367			spin_lock_irqsave(&priv->lock, flags);
368			priv->baud_rate = new_baudrate;
369			priv->current_config = feature_buffer[4];
370			spin_unlock_irqrestore(&priv->lock, flags);
371			/* If we asked for a speed change encode it */
372			if (baud_rate)
373				tty_encode_baud_rate(tty,
374					new_baudrate, new_baudrate);
375		}
376	break;
377	case CYPRESS_GET_CONFIG:
378		if (priv->get_cfg_unsafe) {
379			/* Not implemented for this device,
380			   and if we try to do it we're likely
381			   to crash the hardware. */
382			retval = -ENOTTY;
383			goto out;
384		}
385		dev_dbg(dev, "%s - retreiving serial line settings\n", __func__);
386		do {
387			retval = usb_control_msg(port->serial->dev,
388					usb_rcvctrlpipe(port->serial->dev, 0),
389					HID_REQ_GET_REPORT,
390					USB_DIR_IN | USB_RECIP_INTERFACE | USB_TYPE_CLASS,
391					0x0300, 0, feature_buffer,
392					feature_len, 500);
393
394			if (tries++ >= 3)
395				break;
396		} while (retval != feature_len
397						&& retval != -ENODEV);
398
399		if (retval != feature_len) {
400			dev_err(dev, "%s - failed to retrieve serial line settings - %d\n",
401				__func__, retval);
402			cypress_set_dead(port);
403			goto out;
404		} else {
405			spin_lock_irqsave(&priv->lock, flags);
406			/* store the config in one byte, and later
407			   use bit masks to check values */
408			priv->current_config = feature_buffer[4];
409			priv->baud_rate = get_unaligned_le32(feature_buffer);
410			spin_unlock_irqrestore(&priv->lock, flags);
411		}
412	}
413	spin_lock_irqsave(&priv->lock, flags);
414	++priv->cmd_count;
415	spin_unlock_irqrestore(&priv->lock, flags);
416out:
417	kfree(feature_buffer);
418	return retval;
419} /* cypress_serial_control */
420
421
422static void cypress_set_dead(struct usb_serial_port *port)
423{
424	struct cypress_private *priv = usb_get_serial_port_data(port);
425	unsigned long flags;
426
427	spin_lock_irqsave(&priv->lock, flags);
428	if (!priv->comm_is_ok) {
429		spin_unlock_irqrestore(&priv->lock, flags);
430		return;
431	}
432	priv->comm_is_ok = 0;
433	spin_unlock_irqrestore(&priv->lock, flags);
434
435	dev_err(&port->dev, "cypress_m8 suspending failing port %d - "
436		"interval might be too short\n", port->port_number);
437}
438
439
440/*****************************************************************************
441 * Cypress serial driver functions
442 *****************************************************************************/
443
444
445static int cypress_generic_port_probe(struct usb_serial_port *port)
446{
447	struct usb_serial *serial = port->serial;
448	struct cypress_private *priv;
449
450	if (!port->interrupt_out_urb || !port->interrupt_in_urb) {
451		dev_err(&port->dev, "required endpoint is missing\n");
452		return -ENODEV;
453	}
454
455	priv = kzalloc(sizeof(struct cypress_private), GFP_KERNEL);
456	if (!priv)
457		return -ENOMEM;
458
459	priv->comm_is_ok = !0;
460	spin_lock_init(&priv->lock);
461	if (kfifo_alloc(&priv->write_fifo, CYPRESS_BUF_SIZE, GFP_KERNEL)) {
462		kfree(priv);
463		return -ENOMEM;
464	}
465
466	/* Skip reset for FRWD device. It is a workaound:
467	   device hangs if it receives SET_CONFIGURE in Configured
468	   state. */
469	if (!is_frwd(serial->dev))
470		usb_reset_configuration(serial->dev);
471
472	priv->cmd_ctrl = 0;
473	priv->line_control = 0;
474	priv->termios_initialized = 0;
475	priv->rx_flags = 0;
476	/* Default packet format setting is determined by packet size.
477	   Anything with a size larger then 9 must have a separate
478	   count field since the 3 bit count field is otherwise too
479	   small.  Otherwise we can use the slightly more compact
480	   format.  This is in accordance with the cypress_m8 serial
481	   converter app note. */
482	if (port->interrupt_out_size > 9)
483		priv->pkt_fmt = packet_format_1;
484	else
485		priv->pkt_fmt = packet_format_2;
486
487	if (interval > 0) {
488		priv->write_urb_interval = interval;
489		priv->read_urb_interval = interval;
490		dev_dbg(&port->dev, "%s - read & write intervals forced to %d\n",
491			__func__, interval);
492	} else {
493		priv->write_urb_interval = port->interrupt_out_urb->interval;
494		priv->read_urb_interval = port->interrupt_in_urb->interval;
495		dev_dbg(&port->dev, "%s - intervals: read=%d write=%d\n",
496			__func__, priv->read_urb_interval,
497			priv->write_urb_interval);
498	}
499	usb_set_serial_port_data(port, priv);
500
501	port->port.drain_delay = 256;
502
503	return 0;
504}
505
506
507static int cypress_earthmate_port_probe(struct usb_serial_port *port)
508{
509	struct usb_serial *serial = port->serial;
510	struct cypress_private *priv;
511	int ret;
512
513	ret = cypress_generic_port_probe(port);
514	if (ret) {
515		dev_dbg(&port->dev, "%s - Failed setting up port\n", __func__);
516		return ret;
517	}
518
519	priv = usb_get_serial_port_data(port);
520	priv->chiptype = CT_EARTHMATE;
521	/* All Earthmate devices use the separated-count packet
522	   format!  Idiotic. */
523	priv->pkt_fmt = packet_format_1;
524	if (serial->dev->descriptor.idProduct !=
525				cpu_to_le16(PRODUCT_ID_EARTHMATEUSB)) {
526		/* The old original USB Earthmate seemed able to
527		   handle GET_CONFIG requests; everything they've
528		   produced since that time crashes if this command is
529		   attempted :-( */
530		dev_dbg(&port->dev,
531			"%s - Marking this device as unsafe for GET_CONFIG commands\n",
532			__func__);
533		priv->get_cfg_unsafe = !0;
534	}
535
536	return 0;
537}
538
539static int cypress_hidcom_port_probe(struct usb_serial_port *port)
540{
541	struct cypress_private *priv;
542	int ret;
543
544	ret = cypress_generic_port_probe(port);
545	if (ret) {
546		dev_dbg(&port->dev, "%s - Failed setting up port\n", __func__);
547		return ret;
548	}
549
550	priv = usb_get_serial_port_data(port);
551	priv->chiptype = CT_CYPHIDCOM;
552
553	return 0;
554}
555
556static int cypress_ca42v2_port_probe(struct usb_serial_port *port)
557{
558	struct cypress_private *priv;
559	int ret;
560
561	ret = cypress_generic_port_probe(port);
562	if (ret) {
563		dev_dbg(&port->dev, "%s - Failed setting up port\n", __func__);
564		return ret;
565	}
566
567	priv = usb_get_serial_port_data(port);
568	priv->chiptype = CT_CA42V2;
569
570	return 0;
571}
572
573static int cypress_port_remove(struct usb_serial_port *port)
574{
575	struct cypress_private *priv;
576
577	priv = usb_get_serial_port_data(port);
578
579	kfifo_free(&priv->write_fifo);
580	kfree(priv);
581
582	return 0;
583}
584
585static int cypress_open(struct tty_struct *tty, struct usb_serial_port *port)
586{
587	struct cypress_private *priv = usb_get_serial_port_data(port);
588	struct usb_serial *serial = port->serial;
589	unsigned long flags;
590	int result = 0;
591
592	if (!priv->comm_is_ok)
593		return -EIO;
594
595	/* clear halts before open */
596	usb_clear_halt(serial->dev, 0x81);
597	usb_clear_halt(serial->dev, 0x02);
598
599	spin_lock_irqsave(&priv->lock, flags);
600	/* reset read/write statistics */
601	priv->bytes_in = 0;
602	priv->bytes_out = 0;
603	priv->cmd_count = 0;
604	priv->rx_flags = 0;
605	spin_unlock_irqrestore(&priv->lock, flags);
606
607	/* Set termios */
608	cypress_send(port);
609
610	if (tty)
611		cypress_set_termios(tty, port, &priv->tmp_termios);
612
613	/* setup the port and start reading from the device */
614	usb_fill_int_urb(port->interrupt_in_urb, serial->dev,
615		usb_rcvintpipe(serial->dev, port->interrupt_in_endpointAddress),
616		port->interrupt_in_urb->transfer_buffer,
617		port->interrupt_in_urb->transfer_buffer_length,
618		cypress_read_int_callback, port, priv->read_urb_interval);
619	result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
620
621	if (result) {
622		dev_err(&port->dev,
623			"%s - failed submitting read urb, error %d\n",
624							__func__, result);
625		cypress_set_dead(port);
626	}
627
628	return result;
629} /* cypress_open */
630
631static void cypress_dtr_rts(struct usb_serial_port *port, int on)
632{
633	struct cypress_private *priv = usb_get_serial_port_data(port);
634	/* drop dtr and rts */
635	spin_lock_irq(&priv->lock);
636	if (on == 0)
637		priv->line_control = 0;
638	else
639		priv->line_control = CONTROL_DTR | CONTROL_RTS;
640	priv->cmd_ctrl = 1;
641	spin_unlock_irq(&priv->lock);
642	cypress_write(NULL, port, NULL, 0);
643}
644
645static void cypress_close(struct usb_serial_port *port)
646{
647	struct cypress_private *priv = usb_get_serial_port_data(port);
648	unsigned long flags;
649
650	spin_lock_irqsave(&priv->lock, flags);
651	kfifo_reset_out(&priv->write_fifo);
652	spin_unlock_irqrestore(&priv->lock, flags);
653
654	dev_dbg(&port->dev, "%s - stopping urbs\n", __func__);
655	usb_kill_urb(port->interrupt_in_urb);
656	usb_kill_urb(port->interrupt_out_urb);
657
658	if (stats)
659		dev_info(&port->dev, "Statistics: %d Bytes In | %d Bytes Out | %d Commands Issued\n",
660			priv->bytes_in, priv->bytes_out, priv->cmd_count);
661} /* cypress_close */
662
663
664static int cypress_write(struct tty_struct *tty, struct usb_serial_port *port,
665					const unsigned char *buf, int count)
666{
667	struct cypress_private *priv = usb_get_serial_port_data(port);
668
669	dev_dbg(&port->dev, "%s - %d bytes\n", __func__, count);
670
671	/* line control commands, which need to be executed immediately,
672	   are not put into the buffer for obvious reasons.
673	 */
674	if (priv->cmd_ctrl) {
675		count = 0;
676		goto finish;
677	}
678
679	if (!count)
680		return count;
681
682	count = kfifo_in_locked(&priv->write_fifo, buf, count, &priv->lock);
683
684finish:
685	cypress_send(port);
686
687	return count;
688} /* cypress_write */
689
690
691static void cypress_send(struct usb_serial_port *port)
692{
693	int count = 0, result, offset, actual_size;
694	struct cypress_private *priv = usb_get_serial_port_data(port);
695	struct device *dev = &port->dev;
696	unsigned long flags;
697
698	if (!priv->comm_is_ok)
699		return;
700
701	dev_dbg(dev, "%s - interrupt out size is %d\n", __func__,
702		port->interrupt_out_size);
703
704	spin_lock_irqsave(&priv->lock, flags);
705	if (priv->write_urb_in_use) {
706		dev_dbg(dev, "%s - can't write, urb in use\n", __func__);
707		spin_unlock_irqrestore(&priv->lock, flags);
708		return;
709	}
710	spin_unlock_irqrestore(&priv->lock, flags);
711
712	/* clear buffer */
713	memset(port->interrupt_out_urb->transfer_buffer, 0,
714						port->interrupt_out_size);
715
716	spin_lock_irqsave(&priv->lock, flags);
717	switch (priv->pkt_fmt) {
718	default:
719	case packet_format_1:
720		/* this is for the CY7C64013... */
721		offset = 2;
722		port->interrupt_out_buffer[0] = priv->line_control;
723		break;
724	case packet_format_2:
725		/* this is for the CY7C63743... */
726		offset = 1;
727		port->interrupt_out_buffer[0] = priv->line_control;
728		break;
729	}
730
731	if (priv->line_control & CONTROL_RESET)
732		priv->line_control &= ~CONTROL_RESET;
733
734	if (priv->cmd_ctrl) {
735		priv->cmd_count++;
736		dev_dbg(dev, "%s - line control command being issued\n", __func__);
737		spin_unlock_irqrestore(&priv->lock, flags);
738		goto send;
739	} else
740		spin_unlock_irqrestore(&priv->lock, flags);
741
742	count = kfifo_out_locked(&priv->write_fifo,
743					&port->interrupt_out_buffer[offset],
744					port->interrupt_out_size - offset,
745					&priv->lock);
746	if (count == 0)
747		return;
748
749	switch (priv->pkt_fmt) {
750	default:
751	case packet_format_1:
752		port->interrupt_out_buffer[1] = count;
753		break;
754	case packet_format_2:
755		port->interrupt_out_buffer[0] |= count;
756	}
757
758	dev_dbg(dev, "%s - count is %d\n", __func__, count);
759
760send:
761	spin_lock_irqsave(&priv->lock, flags);
762	priv->write_urb_in_use = 1;
763	spin_unlock_irqrestore(&priv->lock, flags);
764
765	if (priv->cmd_ctrl)
766		actual_size = 1;
767	else
768		actual_size = count +
769			      (priv->pkt_fmt == packet_format_1 ? 2 : 1);
770
771	usb_serial_debug_data(dev, __func__, port->interrupt_out_size,
772			      port->interrupt_out_urb->transfer_buffer);
773
774	usb_fill_int_urb(port->interrupt_out_urb, port->serial->dev,
775		usb_sndintpipe(port->serial->dev, port->interrupt_out_endpointAddress),
776		port->interrupt_out_buffer, port->interrupt_out_size,
777		cypress_write_int_callback, port, priv->write_urb_interval);
778	result = usb_submit_urb(port->interrupt_out_urb, GFP_ATOMIC);
779	if (result) {
780		dev_err_console(port,
781				"%s - failed submitting write urb, error %d\n",
782							__func__, result);
783		priv->write_urb_in_use = 0;
784		cypress_set_dead(port);
785	}
786
787	spin_lock_irqsave(&priv->lock, flags);
788	if (priv->cmd_ctrl)
789		priv->cmd_ctrl = 0;
790
791	/* do not count the line control and size bytes */
792	priv->bytes_out += count;
793	spin_unlock_irqrestore(&priv->lock, flags);
794
795	usb_serial_port_softint(port);
796} /* cypress_send */
797
798
799/* returns how much space is available in the soft buffer */
800static int cypress_write_room(struct tty_struct *tty)
801{
802	struct usb_serial_port *port = tty->driver_data;
803	struct cypress_private *priv = usb_get_serial_port_data(port);
804	int room = 0;
805	unsigned long flags;
806
807	spin_lock_irqsave(&priv->lock, flags);
808	room = kfifo_avail(&priv->write_fifo);
809	spin_unlock_irqrestore(&priv->lock, flags);
810
811	dev_dbg(&port->dev, "%s - returns %d\n", __func__, room);
812	return room;
813}
814
815
816static int cypress_tiocmget(struct tty_struct *tty)
817{
818	struct usb_serial_port *port = tty->driver_data;
819	struct cypress_private *priv = usb_get_serial_port_data(port);
820	__u8 status, control;
821	unsigned int result = 0;
822	unsigned long flags;
823
824	spin_lock_irqsave(&priv->lock, flags);
825	control = priv->line_control;
826	status = priv->current_status;
827	spin_unlock_irqrestore(&priv->lock, flags);
828
829	result = ((control & CONTROL_DTR)        ? TIOCM_DTR : 0)
830		| ((control & CONTROL_RTS)       ? TIOCM_RTS : 0)
831		| ((status & UART_CTS)        ? TIOCM_CTS : 0)
832		| ((status & UART_DSR)        ? TIOCM_DSR : 0)
833		| ((status & UART_RI)         ? TIOCM_RI  : 0)
834		| ((status & UART_CD)         ? TIOCM_CD  : 0);
835
836	dev_dbg(&port->dev, "%s - result = %x\n", __func__, result);
837
838	return result;
839}
840
841
842static int cypress_tiocmset(struct tty_struct *tty,
843			       unsigned int set, unsigned int clear)
844{
845	struct usb_serial_port *port = tty->driver_data;
846	struct cypress_private *priv = usb_get_serial_port_data(port);
847	unsigned long flags;
848
849	spin_lock_irqsave(&priv->lock, flags);
850	if (set & TIOCM_RTS)
851		priv->line_control |= CONTROL_RTS;
852	if (set & TIOCM_DTR)
853		priv->line_control |= CONTROL_DTR;
854	if (clear & TIOCM_RTS)
855		priv->line_control &= ~CONTROL_RTS;
856	if (clear & TIOCM_DTR)
857		priv->line_control &= ~CONTROL_DTR;
858	priv->cmd_ctrl = 1;
859	spin_unlock_irqrestore(&priv->lock, flags);
860
861	return cypress_write(tty, port, NULL, 0);
862}
863
864static void cypress_set_termios(struct tty_struct *tty,
865	struct usb_serial_port *port, struct ktermios *old_termios)
866{
867	struct cypress_private *priv = usb_get_serial_port_data(port);
868	struct device *dev = &port->dev;
869	int data_bits, stop_bits, parity_type, parity_enable;
870	unsigned cflag, iflag;
871	unsigned long flags;
872	__u8 oldlines;
873	int linechange = 0;
874
875	spin_lock_irqsave(&priv->lock, flags);
876	/* We can't clean this one up as we don't know the device type
877	   early enough */
878	if (!priv->termios_initialized) {
879		if (priv->chiptype == CT_EARTHMATE) {
880			tty->termios = tty_std_termios;
881			tty->termios.c_cflag = B4800 | CS8 | CREAD | HUPCL |
882				CLOCAL;
883			tty->termios.c_ispeed = 4800;
884			tty->termios.c_ospeed = 4800;
885		} else if (priv->chiptype == CT_CYPHIDCOM) {
886			tty->termios = tty_std_termios;
887			tty->termios.c_cflag = B9600 | CS8 | CREAD | HUPCL |
888				CLOCAL;
889			tty->termios.c_ispeed = 9600;
890			tty->termios.c_ospeed = 9600;
891		} else if (priv->chiptype == CT_CA42V2) {
892			tty->termios = tty_std_termios;
893			tty->termios.c_cflag = B9600 | CS8 | CREAD | HUPCL |
894				CLOCAL;
895			tty->termios.c_ispeed = 9600;
896			tty->termios.c_ospeed = 9600;
897		}
898		priv->termios_initialized = 1;
899	}
900	spin_unlock_irqrestore(&priv->lock, flags);
901
902	/* Unsupported features need clearing */
903	tty->termios.c_cflag &= ~(CMSPAR|CRTSCTS);
904
905	cflag = tty->termios.c_cflag;
906	iflag = tty->termios.c_iflag;
907
908	/* check if there are new settings */
909	if (old_termios) {
910		spin_lock_irqsave(&priv->lock, flags);
911		priv->tmp_termios = tty->termios;
912		spin_unlock_irqrestore(&priv->lock, flags);
913	}
914
915	/* set number of data bits, parity, stop bits */
916	/* when parity is disabled the parity type bit is ignored */
917
918	/* 1 means 2 stop bits, 0 means 1 stop bit */
919	stop_bits = cflag & CSTOPB ? 1 : 0;
920
921	if (cflag & PARENB) {
922		parity_enable = 1;
923		/* 1 means odd parity, 0 means even parity */
924		parity_type = cflag & PARODD ? 1 : 0;
925	} else
926		parity_enable = parity_type = 0;
927
928	switch (cflag & CSIZE) {
929	case CS5:
930		data_bits = 0;
931		break;
932	case CS6:
933		data_bits = 1;
934		break;
935	case CS7:
936		data_bits = 2;
937		break;
938	case CS8:
939		data_bits = 3;
940		break;
941	default:
942		dev_err(dev, "%s - CSIZE was set, but not CS5-CS8\n", __func__);
943		data_bits = 3;
944	}
945	spin_lock_irqsave(&priv->lock, flags);
946	oldlines = priv->line_control;
947	if ((cflag & CBAUD) == B0) {
948		/* drop dtr and rts */
949		dev_dbg(dev, "%s - dropping the lines, baud rate 0bps\n", __func__);
950		priv->line_control &= ~(CONTROL_DTR | CONTROL_RTS);
951	} else
952		priv->line_control = (CONTROL_DTR | CONTROL_RTS);
953	spin_unlock_irqrestore(&priv->lock, flags);
954
955	dev_dbg(dev, "%s - sending %d stop_bits, %d parity_enable, %d parity_type, %d data_bits (+5)\n",
956		__func__, stop_bits, parity_enable, parity_type, data_bits);
957
958	cypress_serial_control(tty, port, tty_get_baud_rate(tty),
959			data_bits, stop_bits,
960			parity_enable, parity_type,
961			0, CYPRESS_SET_CONFIG);
962
963	/* we perform a CYPRESS_GET_CONFIG so that the current settings are
964	 * filled into the private structure this should confirm that all is
965	 * working if it returns what we just set */
966	cypress_serial_control(tty, port, 0, 0, 0, 0, 0, 0, CYPRESS_GET_CONFIG);
967
968	/* Here we can define custom tty settings for devices; the main tty
969	 * termios flag base comes from empeg.c */
970
971	spin_lock_irqsave(&priv->lock, flags);
972	if (priv->chiptype == CT_EARTHMATE && priv->baud_rate == 4800) {
973		dev_dbg(dev, "Using custom termios settings for a baud rate of 4800bps.\n");
974		/* define custom termios settings for NMEA protocol */
975
976		tty->termios.c_iflag /* input modes - */
977			&= ~(IGNBRK  /* disable ignore break */
978			| BRKINT     /* disable break causes interrupt */
979			| PARMRK     /* disable mark parity errors */
980			| ISTRIP     /* disable clear high bit of input char */
981			| INLCR      /* disable translate NL to CR */
982			| IGNCR      /* disable ignore CR */
983			| ICRNL      /* disable translate CR to NL */
984			| IXON);     /* disable enable XON/XOFF flow control */
985
986		tty->termios.c_oflag /* output modes */
987			&= ~OPOST;    /* disable postprocess output char */
988
989		tty->termios.c_lflag /* line discipline modes */
990			&= ~(ECHO     /* disable echo input characters */
991			| ECHONL      /* disable echo new line */
992			| ICANON      /* disable erase, kill, werase, and rprnt
993					 special characters */
994			| ISIG        /* disable interrupt, quit, and suspend
995					 special characters */
996			| IEXTEN);    /* disable non-POSIX special characters */
997	} /* CT_CYPHIDCOM: Application should handle this for device */
998
999	linechange = (priv->line_control != oldlines);
1000	spin_unlock_irqrestore(&priv->lock, flags);
1001
1002	/* if necessary, set lines */
1003	if (linechange) {
1004		priv->cmd_ctrl = 1;
1005		cypress_write(tty, port, NULL, 0);
1006	}
1007} /* cypress_set_termios */
1008
1009
1010/* returns amount of data still left in soft buffer */
1011static int cypress_chars_in_buffer(struct tty_struct *tty)
1012{
1013	struct usb_serial_port *port = tty->driver_data;
1014	struct cypress_private *priv = usb_get_serial_port_data(port);
1015	int chars = 0;
1016	unsigned long flags;
1017
1018	spin_lock_irqsave(&priv->lock, flags);
1019	chars = kfifo_len(&priv->write_fifo);
1020	spin_unlock_irqrestore(&priv->lock, flags);
1021
1022	dev_dbg(&port->dev, "%s - returns %d\n", __func__, chars);
1023	return chars;
1024}
1025
1026
1027static void cypress_throttle(struct tty_struct *tty)
1028{
1029	struct usb_serial_port *port = tty->driver_data;
1030	struct cypress_private *priv = usb_get_serial_port_data(port);
1031
1032	spin_lock_irq(&priv->lock);
1033	priv->rx_flags = THROTTLED;
1034	spin_unlock_irq(&priv->lock);
1035}
1036
1037
1038static void cypress_unthrottle(struct tty_struct *tty)
1039{
1040	struct usb_serial_port *port = tty->driver_data;
1041	struct cypress_private *priv = usb_get_serial_port_data(port);
1042	int actually_throttled, result;
1043
1044	spin_lock_irq(&priv->lock);
1045	actually_throttled = priv->rx_flags & ACTUALLY_THROTTLED;
1046	priv->rx_flags = 0;
1047	spin_unlock_irq(&priv->lock);
1048
1049	if (!priv->comm_is_ok)
1050		return;
1051
1052	if (actually_throttled) {
1053		result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
1054		if (result) {
1055			dev_err(&port->dev, "%s - failed submitting read urb, "
1056					"error %d\n", __func__, result);
1057			cypress_set_dead(port);
1058		}
1059	}
1060}
1061
1062
1063static void cypress_read_int_callback(struct urb *urb)
1064{
1065	struct usb_serial_port *port = urb->context;
1066	struct cypress_private *priv = usb_get_serial_port_data(port);
1067	struct device *dev = &urb->dev->dev;
1068	struct tty_struct *tty;
1069	unsigned char *data = urb->transfer_buffer;
1070	unsigned long flags;
1071	char tty_flag = TTY_NORMAL;
1072	int havedata = 0;
1073	int bytes = 0;
1074	int result;
1075	int i = 0;
1076	int status = urb->status;
1077
1078	switch (status) {
1079	case 0: /* success */
1080		break;
1081	case -ECONNRESET:
1082	case -ENOENT:
1083	case -ESHUTDOWN:
1084		/* precursor to disconnect so just go away */
1085		return;
1086	case -EPIPE:
1087		/* Can't call usb_clear_halt while in_interrupt */
1088		/* FALLS THROUGH */
1089	default:
1090		/* something ugly is going on... */
1091		dev_err(dev, "%s - unexpected nonzero read status received: %d\n",
1092			__func__, status);
1093		cypress_set_dead(port);
1094		return;
1095	}
1096
1097	spin_lock_irqsave(&priv->lock, flags);
1098	if (priv->rx_flags & THROTTLED) {
1099		dev_dbg(dev, "%s - now throttling\n", __func__);
1100		priv->rx_flags |= ACTUALLY_THROTTLED;
1101		spin_unlock_irqrestore(&priv->lock, flags);
1102		return;
1103	}
1104	spin_unlock_irqrestore(&priv->lock, flags);
1105
1106	tty = tty_port_tty_get(&port->port);
1107	if (!tty) {
1108		dev_dbg(dev, "%s - bad tty pointer - exiting\n", __func__);
1109		return;
1110	}
1111
1112	spin_lock_irqsave(&priv->lock, flags);
1113	result = urb->actual_length;
1114	switch (priv->pkt_fmt) {
1115	default:
1116	case packet_format_1:
1117		/* This is for the CY7C64013... */
1118		priv->current_status = data[0] & 0xF8;
1119		bytes = data[1] + 2;
1120		i = 2;
1121		if (bytes > 2)
1122			havedata = 1;
1123		break;
1124	case packet_format_2:
1125		/* This is for the CY7C63743... */
1126		priv->current_status = data[0] & 0xF8;
1127		bytes = (data[0] & 0x07) + 1;
1128		i = 1;
1129		if (bytes > 1)
1130			havedata = 1;
1131		break;
1132	}
1133	spin_unlock_irqrestore(&priv->lock, flags);
1134	if (result < bytes) {
1135		dev_dbg(dev,
1136			"%s - wrong packet size - received %d bytes but packet said %d bytes\n",
1137			__func__, result, bytes);
1138		goto continue_read;
1139	}
1140
1141	usb_serial_debug_data(&port->dev, __func__, urb->actual_length, data);
1142
1143	spin_lock_irqsave(&priv->lock, flags);
1144	/* check to see if status has changed */
1145	if (priv->current_status != priv->prev_status) {
1146		u8 delta = priv->current_status ^ priv->prev_status;
1147
1148		if (delta & UART_MSR_MASK) {
1149			if (delta & UART_CTS)
1150				port->icount.cts++;
1151			if (delta & UART_DSR)
1152				port->icount.dsr++;
1153			if (delta & UART_RI)
1154				port->icount.rng++;
1155			if (delta & UART_CD)
1156				port->icount.dcd++;
1157
1158			wake_up_interruptible(&port->port.delta_msr_wait);
1159		}
1160
1161		priv->prev_status = priv->current_status;
1162	}
1163	spin_unlock_irqrestore(&priv->lock, flags);
1164
1165	/* hangup, as defined in acm.c... this might be a bad place for it
1166	 * though */
1167	if (tty && !(tty->termios.c_cflag & CLOCAL) &&
1168			!(priv->current_status & UART_CD)) {
1169		dev_dbg(dev, "%s - calling hangup\n", __func__);
1170		tty_hangup(tty);
1171		goto continue_read;
1172	}
1173
1174	/* There is one error bit... I'm assuming it is a parity error
1175	 * indicator as the generic firmware will set this bit to 1 if a
1176	 * parity error occurs.
1177	 * I can not find reference to any other error events. */
1178	spin_lock_irqsave(&priv->lock, flags);
1179	if (priv->current_status & CYP_ERROR) {
1180		spin_unlock_irqrestore(&priv->lock, flags);
1181		tty_flag = TTY_PARITY;
1182		dev_dbg(dev, "%s - Parity Error detected\n", __func__);
1183	} else
1184		spin_unlock_irqrestore(&priv->lock, flags);
1185
1186	/* process read if there is data other than line status */
1187	if (bytes > i) {
1188		tty_insert_flip_string_fixed_flag(&port->port, data + i,
1189				tty_flag, bytes - i);
1190		tty_flip_buffer_push(&port->port);
1191	}
1192
1193	spin_lock_irqsave(&priv->lock, flags);
1194	/* control and status byte(s) are also counted */
1195	priv->bytes_in += bytes;
1196	spin_unlock_irqrestore(&priv->lock, flags);
1197
1198continue_read:
1199	tty_kref_put(tty);
1200
1201	/* Continue trying to always read */
1202
1203	if (priv->comm_is_ok) {
1204		usb_fill_int_urb(port->interrupt_in_urb, port->serial->dev,
1205				usb_rcvintpipe(port->serial->dev,
1206					port->interrupt_in_endpointAddress),
1207				port->interrupt_in_urb->transfer_buffer,
1208				port->interrupt_in_urb->transfer_buffer_length,
1209				cypress_read_int_callback, port,
1210				priv->read_urb_interval);
1211		result = usb_submit_urb(port->interrupt_in_urb, GFP_ATOMIC);
1212		if (result && result != -EPERM) {
1213			dev_err(dev, "%s - failed resubmitting read urb, error %d\n",
1214				__func__, result);
1215			cypress_set_dead(port);
1216		}
1217	}
1218} /* cypress_read_int_callback */
1219
1220
1221static void cypress_write_int_callback(struct urb *urb)
1222{
1223	struct usb_serial_port *port = urb->context;
1224	struct cypress_private *priv = usb_get_serial_port_data(port);
1225	struct device *dev = &urb->dev->dev;
1226	int status = urb->status;
1227
1228	switch (status) {
1229	case 0:
1230		/* success */
1231		break;
1232	case -ECONNRESET:
1233	case -ENOENT:
1234	case -ESHUTDOWN:
1235		/* this urb is terminated, clean up */
1236		dev_dbg(dev, "%s - urb shutting down with status: %d\n",
1237			__func__, status);
1238		priv->write_urb_in_use = 0;
1239		return;
1240	case -EPIPE:
1241		/* Cannot call usb_clear_halt while in_interrupt */
1242		/* FALLTHROUGH */
1243	default:
1244		dev_err(dev, "%s - unexpected nonzero write status received: %d\n",
1245			__func__, status);
1246		cypress_set_dead(port);
1247		break;
1248	}
1249	priv->write_urb_in_use = 0;
1250
1251	/* send any buffered data */
1252	cypress_send(port);
1253}
1254
1255module_usb_serial_driver(serial_drivers, id_table_combined);
1256
1257MODULE_AUTHOR(DRIVER_AUTHOR);
1258MODULE_DESCRIPTION(DRIVER_DESC);
1259MODULE_LICENSE("GPL");
1260
1261module_param(stats, bool, S_IRUGO | S_IWUSR);
1262MODULE_PARM_DESC(stats, "Enable statistics or not");
1263module_param(interval, int, S_IRUGO | S_IWUSR);
1264MODULE_PARM_DESC(interval, "Overrides interrupt interval");
1265module_param(unstable_bauds, bool, S_IRUGO | S_IWUSR);
1266MODULE_PARM_DESC(unstable_bauds, "Allow unstable baud rates");
1267