1// SPDX-License-Identifier: GPL-2.0+
2/*
3 * USB Cypress M8 driver
4 *
5 * Copyright (C) 2004
6 * Lonnie Mendez (dignome@gmail.com)
7 * Copyright (C) 2003,2004
8 * Neil Whelchel (koyama@firstlight.net)
9 *
10 * See Documentation/usb/usb-serial.rst for more information on using this
11 * driver
12 *
13 * See http://geocities.com/i0xox0i for information on this driver and the
14 * earthmate usb device.
15 */
16
17/* Thanks to Neil Whelchel for writing the first cypress m8 implementation
18 for linux. */
19/* Thanks to cypress for providing references for the hid reports. */
20/* Thanks to Jiang Zhang for providing links and for general help. */
21/* Code originates and was built up from ftdi_sio, belkin, pl2303 and others.*/
22
23
24#include <linux/kernel.h>
25#include <linux/errno.h>
26#include <linux/slab.h>
27#include <linux/tty.h>
28#include <linux/tty_driver.h>
29#include <linux/tty_flip.h>
30#include <linux/module.h>
31#include <linux/moduleparam.h>
32#include <linux/spinlock.h>
33#include <linux/usb.h>
34#include <linux/usb/serial.h>
35#include <linux/serial.h>
36#include <linux/kfifo.h>
37#include <linux/delay.h>
38#include <linux/uaccess.h>
39#include <asm/unaligned.h>
40
41#include "cypress_m8.h"
42
43
44static bool stats;
45static int interval;
46static bool unstable_bauds;
47
48#define DRIVER_AUTHOR "Lonnie Mendez <dignome@gmail.com>, Neil Whelchel <koyama@firstlight.net>"
49#define DRIVER_DESC "Cypress USB to Serial Driver"
50
51/* write buffer size defines */
52#define CYPRESS_BUF_SIZE 1024
53
54static const struct usb_device_id id_table_earthmate[] = {
55 { USB_DEVICE(VENDOR_ID_DELORME, PRODUCT_ID_EARTHMATEUSB) },
56 { USB_DEVICE(VENDOR_ID_DELORME, PRODUCT_ID_EARTHMATEUSB_LT20) },
57 { } /* Terminating entry */
58};
59
60static const struct usb_device_id id_table_cyphidcomrs232[] = {
61 { USB_DEVICE(VENDOR_ID_CYPRESS, PRODUCT_ID_CYPHIDCOM) },
62 { USB_DEVICE(VENDOR_ID_SAI, PRODUCT_ID_CYPHIDCOM) },
63 { USB_DEVICE(VENDOR_ID_POWERCOM, PRODUCT_ID_UPS) },
64 { USB_DEVICE(VENDOR_ID_FRWD, PRODUCT_ID_CYPHIDCOM_FRWD) },
65 { } /* Terminating entry */
66};
67
68static const struct usb_device_id id_table_nokiaca42v2[] = {
69 { USB_DEVICE(VENDOR_ID_DAZZLE, PRODUCT_ID_CA42) },
70 { } /* Terminating entry */
71};
72
73static const struct usb_device_id id_table_combined[] = {
74 { USB_DEVICE(VENDOR_ID_DELORME, PRODUCT_ID_EARTHMATEUSB) },
75 { USB_DEVICE(VENDOR_ID_DELORME, PRODUCT_ID_EARTHMATEUSB_LT20) },
76 { USB_DEVICE(VENDOR_ID_CYPRESS, PRODUCT_ID_CYPHIDCOM) },
77 { USB_DEVICE(VENDOR_ID_SAI, PRODUCT_ID_CYPHIDCOM) },
78 { USB_DEVICE(VENDOR_ID_POWERCOM, PRODUCT_ID_UPS) },
79 { USB_DEVICE(VENDOR_ID_FRWD, PRODUCT_ID_CYPHIDCOM_FRWD) },
80 { USB_DEVICE(VENDOR_ID_DAZZLE, PRODUCT_ID_CA42) },
81 { } /* Terminating entry */
82};
83
84MODULE_DEVICE_TABLE(usb, id_table_combined);
85
86enum packet_format {
87 packet_format_1, /* b0:status, b1:payload count */
88 packet_format_2 /* b0[7:3]:status, b0[2:0]:payload count */
89};
90
91struct cypress_private {
92 spinlock_t lock; /* private lock */
93 int chiptype; /* identifier of device, for quirks/etc */
94 int bytes_in; /* used for statistics */
95 int bytes_out; /* used for statistics */
96 int cmd_count; /* used for statistics */
97 int cmd_ctrl; /* always set this to 1 before issuing a command */
98 struct kfifo write_fifo; /* write fifo */
99 int write_urb_in_use; /* write urb in use indicator */
100 int write_urb_interval; /* interval to use for write urb */
101 int read_urb_interval; /* interval to use for read urb */
102 int comm_is_ok; /* true if communication is (still) ok */
103 __u8 line_control; /* holds dtr / rts value */
104 __u8 current_status; /* received from last read - info on dsr,cts,cd,ri,etc */
105 __u8 current_config; /* stores the current configuration byte */
106 __u8 rx_flags; /* throttling - used from whiteheat/ftdi_sio */
107 enum packet_format pkt_fmt; /* format to use for packet send / receive */
108 int get_cfg_unsafe; /* If true, the CYPRESS_GET_CONFIG is unsafe */
109 int baud_rate; /* stores current baud rate in
110 integer form */
111 char prev_status; /* used for TIOCMIWAIT */
112};
113
114/* function prototypes for the Cypress USB to serial device */
115static int cypress_earthmate_port_probe(struct usb_serial_port *port);
116static int cypress_hidcom_port_probe(struct usb_serial_port *port);
117static int cypress_ca42v2_port_probe(struct usb_serial_port *port);
118static void cypress_port_remove(struct usb_serial_port *port);
119static int cypress_open(struct tty_struct *tty, struct usb_serial_port *port);
120static void cypress_close(struct usb_serial_port *port);
121static void cypress_dtr_rts(struct usb_serial_port *port, int on);
122static int cypress_write(struct tty_struct *tty, struct usb_serial_port *port,
123 const unsigned char *buf, int count);
124static void cypress_send(struct usb_serial_port *port);
125static unsigned int cypress_write_room(struct tty_struct *tty);
126static void cypress_earthmate_init_termios(struct tty_struct *tty);
127static void cypress_set_termios(struct tty_struct *tty,
128 struct usb_serial_port *port,
129 const struct ktermios *old_termios);
130static int cypress_tiocmget(struct tty_struct *tty);
131static int cypress_tiocmset(struct tty_struct *tty,
132 unsigned int set, unsigned int clear);
133static unsigned int cypress_chars_in_buffer(struct tty_struct *tty);
134static void cypress_throttle(struct tty_struct *tty);
135static void cypress_unthrottle(struct tty_struct *tty);
136static void cypress_set_dead(struct usb_serial_port *port);
137static void cypress_read_int_callback(struct urb *urb);
138static void cypress_write_int_callback(struct urb *urb);
139
140static struct usb_serial_driver cypress_earthmate_device = {
141 .driver = {
142 .owner = THIS_MODULE,
143 .name = "earthmate",
144 },
145 .description = "DeLorme Earthmate USB",
146 .id_table = id_table_earthmate,
147 .num_ports = 1,
148 .port_probe = cypress_earthmate_port_probe,
149 .port_remove = cypress_port_remove,
150 .open = cypress_open,
151 .close = cypress_close,
152 .dtr_rts = cypress_dtr_rts,
153 .write = cypress_write,
154 .write_room = cypress_write_room,
155 .init_termios = cypress_earthmate_init_termios,
156 .set_termios = cypress_set_termios,
157 .tiocmget = cypress_tiocmget,
158 .tiocmset = cypress_tiocmset,
159 .tiocmiwait = usb_serial_generic_tiocmiwait,
160 .chars_in_buffer = cypress_chars_in_buffer,
161 .throttle = cypress_throttle,
162 .unthrottle = cypress_unthrottle,
163 .read_int_callback = cypress_read_int_callback,
164 .write_int_callback = cypress_write_int_callback,
165};
166
167static struct usb_serial_driver cypress_hidcom_device = {
168 .driver = {
169 .owner = THIS_MODULE,
170 .name = "cyphidcom",
171 },
172 .description = "HID->COM RS232 Adapter",
173 .id_table = id_table_cyphidcomrs232,
174 .num_ports = 1,
175 .port_probe = cypress_hidcom_port_probe,
176 .port_remove = cypress_port_remove,
177 .open = cypress_open,
178 .close = cypress_close,
179 .dtr_rts = cypress_dtr_rts,
180 .write = cypress_write,
181 .write_room = cypress_write_room,
182 .set_termios = cypress_set_termios,
183 .tiocmget = cypress_tiocmget,
184 .tiocmset = cypress_tiocmset,
185 .tiocmiwait = usb_serial_generic_tiocmiwait,
186 .chars_in_buffer = cypress_chars_in_buffer,
187 .throttle = cypress_throttle,
188 .unthrottle = cypress_unthrottle,
189 .read_int_callback = cypress_read_int_callback,
190 .write_int_callback = cypress_write_int_callback,
191};
192
193static struct usb_serial_driver cypress_ca42v2_device = {
194 .driver = {
195 .owner = THIS_MODULE,
196 .name = "nokiaca42v2",
197 },
198 .description = "Nokia CA-42 V2 Adapter",
199 .id_table = id_table_nokiaca42v2,
200 .num_ports = 1,
201 .port_probe = cypress_ca42v2_port_probe,
202 .port_remove = cypress_port_remove,
203 .open = cypress_open,
204 .close = cypress_close,
205 .dtr_rts = cypress_dtr_rts,
206 .write = cypress_write,
207 .write_room = cypress_write_room,
208 .set_termios = cypress_set_termios,
209 .tiocmget = cypress_tiocmget,
210 .tiocmset = cypress_tiocmset,
211 .tiocmiwait = usb_serial_generic_tiocmiwait,
212 .chars_in_buffer = cypress_chars_in_buffer,
213 .throttle = cypress_throttle,
214 .unthrottle = cypress_unthrottle,
215 .read_int_callback = cypress_read_int_callback,
216 .write_int_callback = cypress_write_int_callback,
217};
218
219static struct usb_serial_driver * const serial_drivers[] = {
220 &cypress_earthmate_device, &cypress_hidcom_device,
221 &cypress_ca42v2_device, NULL
222};
223
224/*****************************************************************************
225 * Cypress serial helper functions
226 *****************************************************************************/
227
228/* FRWD Dongle hidcom needs to skip reset and speed checks */
229static inline bool is_frwd(struct usb_device *dev)
230{
231 return ((le16_to_cpu(dev->descriptor.idVendor) == VENDOR_ID_FRWD) &&
232 (le16_to_cpu(dev->descriptor.idProduct) == PRODUCT_ID_CYPHIDCOM_FRWD));
233}
234
235static int analyze_baud_rate(struct usb_serial_port *port, speed_t new_rate)
236{
237 struct cypress_private *priv;
238 priv = usb_get_serial_port_data(port);
239
240 if (unstable_bauds)
241 return new_rate;
242
243 /* FRWD Dongle uses 115200 bps */
244 if (is_frwd(dev: port->serial->dev))
245 return new_rate;
246
247 /*
248 * The general purpose firmware for the Cypress M8 allows for
249 * a maximum speed of 57600bps (I have no idea whether DeLorme
250 * chose to use the general purpose firmware or not), if you
251 * need to modify this speed setting for your own project
252 * please add your own chiptype and modify the code likewise.
253 * The Cypress HID->COM device will work successfully up to
254 * 115200bps (but the actual throughput is around 3kBps).
255 */
256 if (port->serial->dev->speed == USB_SPEED_LOW) {
257 /*
258 * Mike Isely <isely@pobox.com> 2-Feb-2008: The
259 * Cypress app note that describes this mechanism
260 * states that the low-speed part can't handle more
261 * than 800 bytes/sec, in which case 4800 baud is the
262 * safest speed for a part like that.
263 */
264 if (new_rate > 4800) {
265 dev_dbg(&port->dev,
266 "%s - failed setting baud rate, device incapable speed %d\n",
267 __func__, new_rate);
268 return -1;
269 }
270 }
271 switch (priv->chiptype) {
272 case CT_EARTHMATE:
273 if (new_rate <= 600) {
274 /* 300 and 600 baud rates are supported under
275 * the generic firmware, but are not used with
276 * NMEA and SiRF protocols */
277 dev_dbg(&port->dev,
278 "%s - failed setting baud rate, unsupported speed of %d on Earthmate GPS\n",
279 __func__, new_rate);
280 return -1;
281 }
282 break;
283 default:
284 break;
285 }
286 return new_rate;
287}
288
289
290/* This function can either set or retrieve the current serial line settings */
291static int cypress_serial_control(struct tty_struct *tty,
292 struct usb_serial_port *port, speed_t baud_rate, int data_bits,
293 int stop_bits, int parity_enable, int parity_type, int reset,
294 int cypress_request_type)
295{
296 int new_baudrate = 0, retval = 0, tries = 0;
297 struct cypress_private *priv;
298 struct device *dev = &port->dev;
299 u8 *feature_buffer;
300 const unsigned int feature_len = 5;
301 unsigned long flags;
302
303 priv = usb_get_serial_port_data(port);
304
305 if (!priv->comm_is_ok)
306 return -ENODEV;
307
308 feature_buffer = kcalloc(n: feature_len, size: sizeof(u8), GFP_KERNEL);
309 if (!feature_buffer)
310 return -ENOMEM;
311
312 switch (cypress_request_type) {
313 case CYPRESS_SET_CONFIG:
314 /* 0 means 'Hang up' so doesn't change the true bit rate */
315 new_baudrate = priv->baud_rate;
316 if (baud_rate && baud_rate != priv->baud_rate) {
317 dev_dbg(dev, "%s - baud rate is changing\n", __func__);
318 retval = analyze_baud_rate(port, new_rate: baud_rate);
319 if (retval >= 0) {
320 new_baudrate = retval;
321 dev_dbg(dev, "%s - New baud rate set to %d\n",
322 __func__, new_baudrate);
323 }
324 }
325 dev_dbg(dev, "%s - baud rate is being sent as %d\n", __func__,
326 new_baudrate);
327
328 /* fill the feature_buffer with new configuration */
329 put_unaligned_le32(val: new_baudrate, p: feature_buffer);
330 feature_buffer[4] |= data_bits - 5; /* assign data bits in 2 bit space ( max 3 ) */
331 /* 1 bit gap */
332 feature_buffer[4] |= (stop_bits << 3); /* assign stop bits in 1 bit space */
333 feature_buffer[4] |= (parity_enable << 4); /* assign parity flag in 1 bit space */
334 feature_buffer[4] |= (parity_type << 5); /* assign parity type in 1 bit space */
335 /* 1 bit gap */
336 feature_buffer[4] |= (reset << 7); /* assign reset at end of byte, 1 bit space */
337
338 dev_dbg(dev, "%s - device is being sent this feature report:\n", __func__);
339 dev_dbg(dev, "%s - %02X - %02X - %02X - %02X - %02X\n", __func__,
340 feature_buffer[0], feature_buffer[1],
341 feature_buffer[2], feature_buffer[3],
342 feature_buffer[4]);
343
344 do {
345 retval = usb_control_msg(dev: port->serial->dev,
346 usb_sndctrlpipe(port->serial->dev, 0),
347 HID_REQ_SET_REPORT,
348 USB_DIR_OUT | USB_RECIP_INTERFACE | USB_TYPE_CLASS,
349 value: 0x0300, index: 0, data: feature_buffer,
350 size: feature_len, timeout: 500);
351
352 if (tries++ >= 3)
353 break;
354
355 } while (retval != feature_len &&
356 retval != -ENODEV);
357
358 if (retval != feature_len) {
359 dev_err(dev, "%s - failed sending serial line settings - %d\n",
360 __func__, retval);
361 cypress_set_dead(port);
362 } else {
363 spin_lock_irqsave(&priv->lock, flags);
364 priv->baud_rate = new_baudrate;
365 priv->current_config = feature_buffer[4];
366 spin_unlock_irqrestore(lock: &priv->lock, flags);
367 /* If we asked for a speed change encode it */
368 if (baud_rate)
369 tty_encode_baud_rate(tty,
370 ibaud: new_baudrate, obaud: new_baudrate);
371 }
372 break;
373 case CYPRESS_GET_CONFIG:
374 if (priv->get_cfg_unsafe) {
375 /* Not implemented for this device,
376 and if we try to do it we're likely
377 to crash the hardware. */
378 retval = -ENOTTY;
379 goto out;
380 }
381 dev_dbg(dev, "%s - retrieving serial line settings\n", __func__);
382 do {
383 retval = usb_control_msg(dev: port->serial->dev,
384 usb_rcvctrlpipe(port->serial->dev, 0),
385 HID_REQ_GET_REPORT,
386 USB_DIR_IN | USB_RECIP_INTERFACE | USB_TYPE_CLASS,
387 value: 0x0300, index: 0, data: feature_buffer,
388 size: feature_len, timeout: 500);
389
390 if (tries++ >= 3)
391 break;
392 } while (retval != feature_len
393 && retval != -ENODEV);
394
395 if (retval != feature_len) {
396 dev_err(dev, "%s - failed to retrieve serial line settings - %d\n",
397 __func__, retval);
398 cypress_set_dead(port);
399 goto out;
400 } else {
401 spin_lock_irqsave(&priv->lock, flags);
402 /* store the config in one byte, and later
403 use bit masks to check values */
404 priv->current_config = feature_buffer[4];
405 priv->baud_rate = get_unaligned_le32(p: feature_buffer);
406 spin_unlock_irqrestore(lock: &priv->lock, flags);
407 }
408 }
409 spin_lock_irqsave(&priv->lock, flags);
410 ++priv->cmd_count;
411 spin_unlock_irqrestore(lock: &priv->lock, flags);
412out:
413 kfree(objp: feature_buffer);
414 return retval;
415} /* cypress_serial_control */
416
417
418static void cypress_set_dead(struct usb_serial_port *port)
419{
420 struct cypress_private *priv = usb_get_serial_port_data(port);
421 unsigned long flags;
422
423 spin_lock_irqsave(&priv->lock, flags);
424 if (!priv->comm_is_ok) {
425 spin_unlock_irqrestore(lock: &priv->lock, flags);
426 return;
427 }
428 priv->comm_is_ok = 0;
429 spin_unlock_irqrestore(lock: &priv->lock, flags);
430
431 dev_err(&port->dev, "cypress_m8 suspending failing port %d - "
432 "interval might be too short\n", port->port_number);
433}
434
435
436/*****************************************************************************
437 * Cypress serial driver functions
438 *****************************************************************************/
439
440
441static int cypress_generic_port_probe(struct usb_serial_port *port)
442{
443 struct usb_serial *serial = port->serial;
444 struct cypress_private *priv;
445
446 if (!port->interrupt_out_urb || !port->interrupt_in_urb) {
447 dev_err(&port->dev, "required endpoint is missing\n");
448 return -ENODEV;
449 }
450
451 priv = kzalloc(size: sizeof(struct cypress_private), GFP_KERNEL);
452 if (!priv)
453 return -ENOMEM;
454
455 priv->comm_is_ok = !0;
456 spin_lock_init(&priv->lock);
457 if (kfifo_alloc(&priv->write_fifo, CYPRESS_BUF_SIZE, GFP_KERNEL)) {
458 kfree(objp: priv);
459 return -ENOMEM;
460 }
461
462 /* Skip reset for FRWD device. It is a workaound:
463 device hangs if it receives SET_CONFIGURE in Configured
464 state. */
465 if (!is_frwd(dev: serial->dev))
466 usb_reset_configuration(dev: serial->dev);
467
468 priv->cmd_ctrl = 0;
469 priv->line_control = 0;
470 priv->rx_flags = 0;
471 /* Default packet format setting is determined by packet size.
472 Anything with a size larger then 9 must have a separate
473 count field since the 3 bit count field is otherwise too
474 small. Otherwise we can use the slightly more compact
475 format. This is in accordance with the cypress_m8 serial
476 converter app note. */
477 if (port->interrupt_out_size > 9)
478 priv->pkt_fmt = packet_format_1;
479 else
480 priv->pkt_fmt = packet_format_2;
481
482 if (interval > 0) {
483 priv->write_urb_interval = interval;
484 priv->read_urb_interval = interval;
485 dev_dbg(&port->dev, "%s - read & write intervals forced to %d\n",
486 __func__, interval);
487 } else {
488 priv->write_urb_interval = port->interrupt_out_urb->interval;
489 priv->read_urb_interval = port->interrupt_in_urb->interval;
490 dev_dbg(&port->dev, "%s - intervals: read=%d write=%d\n",
491 __func__, priv->read_urb_interval,
492 priv->write_urb_interval);
493 }
494 usb_set_serial_port_data(port, data: priv);
495
496 port->port.drain_delay = 256;
497
498 return 0;
499}
500
501
502static int cypress_earthmate_port_probe(struct usb_serial_port *port)
503{
504 struct usb_serial *serial = port->serial;
505 struct cypress_private *priv;
506 int ret;
507
508 ret = cypress_generic_port_probe(port);
509 if (ret) {
510 dev_dbg(&port->dev, "%s - Failed setting up port\n", __func__);
511 return ret;
512 }
513
514 priv = usb_get_serial_port_data(port);
515 priv->chiptype = CT_EARTHMATE;
516 /* All Earthmate devices use the separated-count packet
517 format! Idiotic. */
518 priv->pkt_fmt = packet_format_1;
519 if (serial->dev->descriptor.idProduct !=
520 cpu_to_le16(PRODUCT_ID_EARTHMATEUSB)) {
521 /* The old original USB Earthmate seemed able to
522 handle GET_CONFIG requests; everything they've
523 produced since that time crashes if this command is
524 attempted :-( */
525 dev_dbg(&port->dev,
526 "%s - Marking this device as unsafe for GET_CONFIG commands\n",
527 __func__);
528 priv->get_cfg_unsafe = !0;
529 }
530
531 return 0;
532}
533
534static int cypress_hidcom_port_probe(struct usb_serial_port *port)
535{
536 struct cypress_private *priv;
537 int ret;
538
539 ret = cypress_generic_port_probe(port);
540 if (ret) {
541 dev_dbg(&port->dev, "%s - Failed setting up port\n", __func__);
542 return ret;
543 }
544
545 priv = usb_get_serial_port_data(port);
546 priv->chiptype = CT_CYPHIDCOM;
547
548 return 0;
549}
550
551static int cypress_ca42v2_port_probe(struct usb_serial_port *port)
552{
553 struct cypress_private *priv;
554 int ret;
555
556 ret = cypress_generic_port_probe(port);
557 if (ret) {
558 dev_dbg(&port->dev, "%s - Failed setting up port\n", __func__);
559 return ret;
560 }
561
562 priv = usb_get_serial_port_data(port);
563 priv->chiptype = CT_CA42V2;
564
565 return 0;
566}
567
568static void cypress_port_remove(struct usb_serial_port *port)
569{
570 struct cypress_private *priv;
571
572 priv = usb_get_serial_port_data(port);
573
574 kfifo_free(&priv->write_fifo);
575 kfree(objp: priv);
576}
577
578static int cypress_open(struct tty_struct *tty, struct usb_serial_port *port)
579{
580 struct cypress_private *priv = usb_get_serial_port_data(port);
581 struct usb_serial *serial = port->serial;
582 unsigned long flags;
583 int result = 0;
584
585 if (!priv->comm_is_ok)
586 return -EIO;
587
588 /* clear halts before open */
589 usb_clear_halt(dev: serial->dev, pipe: 0x81);
590 usb_clear_halt(dev: serial->dev, pipe: 0x02);
591
592 spin_lock_irqsave(&priv->lock, flags);
593 /* reset read/write statistics */
594 priv->bytes_in = 0;
595 priv->bytes_out = 0;
596 priv->cmd_count = 0;
597 priv->rx_flags = 0;
598 spin_unlock_irqrestore(lock: &priv->lock, flags);
599
600 /* Set termios */
601 cypress_send(port);
602
603 if (tty)
604 cypress_set_termios(tty, port, NULL);
605
606 /* setup the port and start reading from the device */
607 usb_fill_int_urb(urb: port->interrupt_in_urb, dev: serial->dev,
608 usb_rcvintpipe(serial->dev, port->interrupt_in_endpointAddress),
609 transfer_buffer: port->interrupt_in_urb->transfer_buffer,
610 buffer_length: port->interrupt_in_urb->transfer_buffer_length,
611 complete_fn: cypress_read_int_callback, context: port, interval: priv->read_urb_interval);
612 result = usb_submit_urb(urb: port->interrupt_in_urb, GFP_KERNEL);
613
614 if (result) {
615 dev_err(&port->dev,
616 "%s - failed submitting read urb, error %d\n",
617 __func__, result);
618 cypress_set_dead(port);
619 }
620
621 return result;
622} /* cypress_open */
623
624static void cypress_dtr_rts(struct usb_serial_port *port, int on)
625{
626 struct cypress_private *priv = usb_get_serial_port_data(port);
627 /* drop dtr and rts */
628 spin_lock_irq(lock: &priv->lock);
629 if (on == 0)
630 priv->line_control = 0;
631 else
632 priv->line_control = CONTROL_DTR | CONTROL_RTS;
633 priv->cmd_ctrl = 1;
634 spin_unlock_irq(lock: &priv->lock);
635 cypress_write(NULL, port, NULL, count: 0);
636}
637
638static void cypress_close(struct usb_serial_port *port)
639{
640 struct cypress_private *priv = usb_get_serial_port_data(port);
641 unsigned long flags;
642
643 spin_lock_irqsave(&priv->lock, flags);
644 kfifo_reset_out(&priv->write_fifo);
645 spin_unlock_irqrestore(lock: &priv->lock, flags);
646
647 dev_dbg(&port->dev, "%s - stopping urbs\n", __func__);
648 usb_kill_urb(urb: port->interrupt_in_urb);
649 usb_kill_urb(urb: port->interrupt_out_urb);
650
651 if (stats)
652 dev_info(&port->dev, "Statistics: %d Bytes In | %d Bytes Out | %d Commands Issued\n",
653 priv->bytes_in, priv->bytes_out, priv->cmd_count);
654} /* cypress_close */
655
656
657static int cypress_write(struct tty_struct *tty, struct usb_serial_port *port,
658 const unsigned char *buf, int count)
659{
660 struct cypress_private *priv = usb_get_serial_port_data(port);
661
662 dev_dbg(&port->dev, "%s - %d bytes\n", __func__, count);
663
664 /* line control commands, which need to be executed immediately,
665 are not put into the buffer for obvious reasons.
666 */
667 if (priv->cmd_ctrl) {
668 count = 0;
669 goto finish;
670 }
671
672 if (!count)
673 return count;
674
675 count = kfifo_in_locked(&priv->write_fifo, buf, count, &priv->lock);
676
677finish:
678 cypress_send(port);
679
680 return count;
681} /* cypress_write */
682
683
684static void cypress_send(struct usb_serial_port *port)
685{
686 int count = 0, result, offset, actual_size;
687 struct cypress_private *priv = usb_get_serial_port_data(port);
688 struct device *dev = &port->dev;
689 unsigned long flags;
690
691 if (!priv->comm_is_ok)
692 return;
693
694 dev_dbg(dev, "%s - interrupt out size is %d\n", __func__,
695 port->interrupt_out_size);
696
697 spin_lock_irqsave(&priv->lock, flags);
698 if (priv->write_urb_in_use) {
699 dev_dbg(dev, "%s - can't write, urb in use\n", __func__);
700 spin_unlock_irqrestore(lock: &priv->lock, flags);
701 return;
702 }
703 spin_unlock_irqrestore(lock: &priv->lock, flags);
704
705 /* clear buffer */
706 memset(port->interrupt_out_urb->transfer_buffer, 0,
707 port->interrupt_out_size);
708
709 spin_lock_irqsave(&priv->lock, flags);
710 switch (priv->pkt_fmt) {
711 default:
712 case packet_format_1:
713 /* this is for the CY7C64013... */
714 offset = 2;
715 port->interrupt_out_buffer[0] = priv->line_control;
716 break;
717 case packet_format_2:
718 /* this is for the CY7C63743... */
719 offset = 1;
720 port->interrupt_out_buffer[0] = priv->line_control;
721 break;
722 }
723
724 if (priv->line_control & CONTROL_RESET)
725 priv->line_control &= ~CONTROL_RESET;
726
727 if (priv->cmd_ctrl) {
728 priv->cmd_count++;
729 dev_dbg(dev, "%s - line control command being issued\n", __func__);
730 spin_unlock_irqrestore(lock: &priv->lock, flags);
731 goto send;
732 } else
733 spin_unlock_irqrestore(lock: &priv->lock, flags);
734
735 count = kfifo_out_locked(&priv->write_fifo,
736 &port->interrupt_out_buffer[offset],
737 port->interrupt_out_size - offset,
738 &priv->lock);
739 if (count == 0)
740 return;
741
742 switch (priv->pkt_fmt) {
743 default:
744 case packet_format_1:
745 port->interrupt_out_buffer[1] = count;
746 break;
747 case packet_format_2:
748 port->interrupt_out_buffer[0] |= count;
749 }
750
751 dev_dbg(dev, "%s - count is %d\n", __func__, count);
752
753send:
754 spin_lock_irqsave(&priv->lock, flags);
755 priv->write_urb_in_use = 1;
756 spin_unlock_irqrestore(lock: &priv->lock, flags);
757
758 if (priv->cmd_ctrl)
759 actual_size = 1;
760 else
761 actual_size = count +
762 (priv->pkt_fmt == packet_format_1 ? 2 : 1);
763
764 usb_serial_debug_data(dev, function: __func__, size: port->interrupt_out_size,
765 data: port->interrupt_out_urb->transfer_buffer);
766
767 usb_fill_int_urb(urb: port->interrupt_out_urb, dev: port->serial->dev,
768 usb_sndintpipe(port->serial->dev, port->interrupt_out_endpointAddress),
769 transfer_buffer: port->interrupt_out_buffer, buffer_length: actual_size,
770 complete_fn: cypress_write_int_callback, context: port, interval: priv->write_urb_interval);
771 result = usb_submit_urb(urb: port->interrupt_out_urb, GFP_ATOMIC);
772 if (result) {
773 dev_err_console(port,
774 "%s - failed submitting write urb, error %d\n",
775 __func__, result);
776 priv->write_urb_in_use = 0;
777 cypress_set_dead(port);
778 }
779
780 spin_lock_irqsave(&priv->lock, flags);
781 if (priv->cmd_ctrl)
782 priv->cmd_ctrl = 0;
783
784 /* do not count the line control and size bytes */
785 priv->bytes_out += count;
786 spin_unlock_irqrestore(lock: &priv->lock, flags);
787
788 usb_serial_port_softint(port);
789} /* cypress_send */
790
791
792/* returns how much space is available in the soft buffer */
793static unsigned int cypress_write_room(struct tty_struct *tty)
794{
795 struct usb_serial_port *port = tty->driver_data;
796 struct cypress_private *priv = usb_get_serial_port_data(port);
797 unsigned int room;
798 unsigned long flags;
799
800 spin_lock_irqsave(&priv->lock, flags);
801 room = kfifo_avail(&priv->write_fifo);
802 spin_unlock_irqrestore(lock: &priv->lock, flags);
803
804 dev_dbg(&port->dev, "%s - returns %u\n", __func__, room);
805 return room;
806}
807
808
809static int cypress_tiocmget(struct tty_struct *tty)
810{
811 struct usb_serial_port *port = tty->driver_data;
812 struct cypress_private *priv = usb_get_serial_port_data(port);
813 __u8 status, control;
814 unsigned int result = 0;
815 unsigned long flags;
816
817 spin_lock_irqsave(&priv->lock, flags);
818 control = priv->line_control;
819 status = priv->current_status;
820 spin_unlock_irqrestore(lock: &priv->lock, flags);
821
822 result = ((control & CONTROL_DTR) ? TIOCM_DTR : 0)
823 | ((control & CONTROL_RTS) ? TIOCM_RTS : 0)
824 | ((status & UART_CTS) ? TIOCM_CTS : 0)
825 | ((status & UART_DSR) ? TIOCM_DSR : 0)
826 | ((status & UART_RI) ? TIOCM_RI : 0)
827 | ((status & UART_CD) ? TIOCM_CD : 0);
828
829 dev_dbg(&port->dev, "%s - result = %x\n", __func__, result);
830
831 return result;
832}
833
834
835static int cypress_tiocmset(struct tty_struct *tty,
836 unsigned int set, unsigned int clear)
837{
838 struct usb_serial_port *port = tty->driver_data;
839 struct cypress_private *priv = usb_get_serial_port_data(port);
840 unsigned long flags;
841
842 spin_lock_irqsave(&priv->lock, flags);
843 if (set & TIOCM_RTS)
844 priv->line_control |= CONTROL_RTS;
845 if (set & TIOCM_DTR)
846 priv->line_control |= CONTROL_DTR;
847 if (clear & TIOCM_RTS)
848 priv->line_control &= ~CONTROL_RTS;
849 if (clear & TIOCM_DTR)
850 priv->line_control &= ~CONTROL_DTR;
851 priv->cmd_ctrl = 1;
852 spin_unlock_irqrestore(lock: &priv->lock, flags);
853
854 return cypress_write(tty, port, NULL, count: 0);
855}
856
857static void cypress_earthmate_init_termios(struct tty_struct *tty)
858{
859 tty_encode_baud_rate(tty, ibaud: 4800, obaud: 4800);
860}
861
862static void cypress_set_termios(struct tty_struct *tty,
863 struct usb_serial_port *port,
864 const struct ktermios *old_termios)
865{
866 struct cypress_private *priv = usb_get_serial_port_data(port);
867 struct device *dev = &port->dev;
868 int data_bits, stop_bits, parity_type, parity_enable;
869 unsigned int cflag;
870 unsigned long flags;
871 __u8 oldlines;
872 int linechange = 0;
873
874 /* Unsupported features need clearing */
875 tty->termios.c_cflag &= ~(CMSPAR|CRTSCTS);
876
877 cflag = tty->termios.c_cflag;
878
879 /* set number of data bits, parity, stop bits */
880 /* when parity is disabled the parity type bit is ignored */
881
882 /* 1 means 2 stop bits, 0 means 1 stop bit */
883 stop_bits = cflag & CSTOPB ? 1 : 0;
884
885 if (cflag & PARENB) {
886 parity_enable = 1;
887 /* 1 means odd parity, 0 means even parity */
888 parity_type = cflag & PARODD ? 1 : 0;
889 } else
890 parity_enable = parity_type = 0;
891
892 data_bits = tty_get_char_size(cflag);
893
894 spin_lock_irqsave(&priv->lock, flags);
895 oldlines = priv->line_control;
896 if ((cflag & CBAUD) == B0) {
897 /* drop dtr and rts */
898 dev_dbg(dev, "%s - dropping the lines, baud rate 0bps\n", __func__);
899 priv->line_control &= ~(CONTROL_DTR | CONTROL_RTS);
900 } else
901 priv->line_control = (CONTROL_DTR | CONTROL_RTS);
902 spin_unlock_irqrestore(lock: &priv->lock, flags);
903
904 dev_dbg(dev, "%s - sending %d stop_bits, %d parity_enable, %d parity_type, %d data_bits (+5)\n",
905 __func__, stop_bits, parity_enable, parity_type, data_bits);
906
907 cypress_serial_control(tty, port, baud_rate: tty_get_baud_rate(tty),
908 data_bits, stop_bits,
909 parity_enable, parity_type,
910 reset: 0, CYPRESS_SET_CONFIG);
911
912 /* we perform a CYPRESS_GET_CONFIG so that the current settings are
913 * filled into the private structure this should confirm that all is
914 * working if it returns what we just set */
915 cypress_serial_control(tty, port, baud_rate: 0, data_bits: 0, stop_bits: 0, parity_enable: 0, parity_type: 0, reset: 0, CYPRESS_GET_CONFIG);
916
917 /* Here we can define custom tty settings for devices; the main tty
918 * termios flag base comes from empeg.c */
919
920 spin_lock_irqsave(&priv->lock, flags);
921 if (priv->chiptype == CT_EARTHMATE && priv->baud_rate == 4800) {
922 dev_dbg(dev, "Using custom termios settings for a baud rate of 4800bps.\n");
923 /* define custom termios settings for NMEA protocol */
924
925 tty->termios.c_iflag /* input modes - */
926 &= ~(IGNBRK /* disable ignore break */
927 | BRKINT /* disable break causes interrupt */
928 | PARMRK /* disable mark parity errors */
929 | ISTRIP /* disable clear high bit of input char */
930 | INLCR /* disable translate NL to CR */
931 | IGNCR /* disable ignore CR */
932 | ICRNL /* disable translate CR to NL */
933 | IXON); /* disable enable XON/XOFF flow control */
934
935 tty->termios.c_oflag /* output modes */
936 &= ~OPOST; /* disable postprocess output char */
937
938 tty->termios.c_lflag /* line discipline modes */
939 &= ~(ECHO /* disable echo input characters */
940 | ECHONL /* disable echo new line */
941 | ICANON /* disable erase, kill, werase, and rprnt
942 special characters */
943 | ISIG /* disable interrupt, quit, and suspend
944 special characters */
945 | IEXTEN); /* disable non-POSIX special characters */
946 } /* CT_CYPHIDCOM: Application should handle this for device */
947
948 linechange = (priv->line_control != oldlines);
949 spin_unlock_irqrestore(lock: &priv->lock, flags);
950
951 /* if necessary, set lines */
952 if (linechange) {
953 priv->cmd_ctrl = 1;
954 cypress_write(tty, port, NULL, count: 0);
955 }
956} /* cypress_set_termios */
957
958
959/* returns amount of data still left in soft buffer */
960static unsigned int cypress_chars_in_buffer(struct tty_struct *tty)
961{
962 struct usb_serial_port *port = tty->driver_data;
963 struct cypress_private *priv = usb_get_serial_port_data(port);
964 unsigned int chars;
965 unsigned long flags;
966
967 spin_lock_irqsave(&priv->lock, flags);
968 chars = kfifo_len(&priv->write_fifo);
969 spin_unlock_irqrestore(lock: &priv->lock, flags);
970
971 dev_dbg(&port->dev, "%s - returns %u\n", __func__, chars);
972 return chars;
973}
974
975
976static void cypress_throttle(struct tty_struct *tty)
977{
978 struct usb_serial_port *port = tty->driver_data;
979 struct cypress_private *priv = usb_get_serial_port_data(port);
980
981 spin_lock_irq(lock: &priv->lock);
982 priv->rx_flags = THROTTLED;
983 spin_unlock_irq(lock: &priv->lock);
984}
985
986
987static void cypress_unthrottle(struct tty_struct *tty)
988{
989 struct usb_serial_port *port = tty->driver_data;
990 struct cypress_private *priv = usb_get_serial_port_data(port);
991 int actually_throttled, result;
992
993 spin_lock_irq(lock: &priv->lock);
994 actually_throttled = priv->rx_flags & ACTUALLY_THROTTLED;
995 priv->rx_flags = 0;
996 spin_unlock_irq(lock: &priv->lock);
997
998 if (!priv->comm_is_ok)
999 return;
1000
1001 if (actually_throttled) {
1002 result = usb_submit_urb(urb: port->interrupt_in_urb, GFP_KERNEL);
1003 if (result) {
1004 dev_err(&port->dev, "%s - failed submitting read urb, "
1005 "error %d\n", __func__, result);
1006 cypress_set_dead(port);
1007 }
1008 }
1009}
1010
1011
1012static void cypress_read_int_callback(struct urb *urb)
1013{
1014 struct usb_serial_port *port = urb->context;
1015 struct cypress_private *priv = usb_get_serial_port_data(port);
1016 struct device *dev = &urb->dev->dev;
1017 struct tty_struct *tty;
1018 unsigned char *data = urb->transfer_buffer;
1019 unsigned long flags;
1020 char tty_flag = TTY_NORMAL;
1021 int bytes = 0;
1022 int result;
1023 int i = 0;
1024 int status = urb->status;
1025
1026 switch (status) {
1027 case 0: /* success */
1028 break;
1029 case -ECONNRESET:
1030 case -ENOENT:
1031 case -ESHUTDOWN:
1032 /* precursor to disconnect so just go away */
1033 return;
1034 case -EPIPE:
1035 /* Can't call usb_clear_halt while in_interrupt */
1036 fallthrough;
1037 default:
1038 /* something ugly is going on... */
1039 dev_err(dev, "%s - unexpected nonzero read status received: %d\n",
1040 __func__, status);
1041 cypress_set_dead(port);
1042 return;
1043 }
1044
1045 spin_lock_irqsave(&priv->lock, flags);
1046 if (priv->rx_flags & THROTTLED) {
1047 dev_dbg(dev, "%s - now throttling\n", __func__);
1048 priv->rx_flags |= ACTUALLY_THROTTLED;
1049 spin_unlock_irqrestore(lock: &priv->lock, flags);
1050 return;
1051 }
1052 spin_unlock_irqrestore(lock: &priv->lock, flags);
1053
1054 tty = tty_port_tty_get(port: &port->port);
1055 if (!tty) {
1056 dev_dbg(dev, "%s - bad tty pointer - exiting\n", __func__);
1057 return;
1058 }
1059
1060 spin_lock_irqsave(&priv->lock, flags);
1061 result = urb->actual_length;
1062 switch (priv->pkt_fmt) {
1063 default:
1064 case packet_format_1:
1065 /* This is for the CY7C64013... */
1066 priv->current_status = data[0] & 0xF8;
1067 bytes = data[1] + 2;
1068 i = 2;
1069 break;
1070 case packet_format_2:
1071 /* This is for the CY7C63743... */
1072 priv->current_status = data[0] & 0xF8;
1073 bytes = (data[0] & 0x07) + 1;
1074 i = 1;
1075 break;
1076 }
1077 spin_unlock_irqrestore(lock: &priv->lock, flags);
1078 if (result < bytes) {
1079 dev_dbg(dev,
1080 "%s - wrong packet size - received %d bytes but packet said %d bytes\n",
1081 __func__, result, bytes);
1082 goto continue_read;
1083 }
1084
1085 usb_serial_debug_data(dev: &port->dev, function: __func__, size: urb->actual_length, data);
1086
1087 spin_lock_irqsave(&priv->lock, flags);
1088 /* check to see if status has changed */
1089 if (priv->current_status != priv->prev_status) {
1090 u8 delta = priv->current_status ^ priv->prev_status;
1091
1092 if (delta & UART_MSR_MASK) {
1093 if (delta & UART_CTS)
1094 port->icount.cts++;
1095 if (delta & UART_DSR)
1096 port->icount.dsr++;
1097 if (delta & UART_RI)
1098 port->icount.rng++;
1099 if (delta & UART_CD)
1100 port->icount.dcd++;
1101
1102 wake_up_interruptible(&port->port.delta_msr_wait);
1103 }
1104
1105 priv->prev_status = priv->current_status;
1106 }
1107 spin_unlock_irqrestore(lock: &priv->lock, flags);
1108
1109 /* hangup, as defined in acm.c... this might be a bad place for it
1110 * though */
1111 if (tty && !C_CLOCAL(tty) && !(priv->current_status & UART_CD)) {
1112 dev_dbg(dev, "%s - calling hangup\n", __func__);
1113 tty_hangup(tty);
1114 goto continue_read;
1115 }
1116
1117 /* There is one error bit... I'm assuming it is a parity error
1118 * indicator as the generic firmware will set this bit to 1 if a
1119 * parity error occurs.
1120 * I can not find reference to any other error events. */
1121 spin_lock_irqsave(&priv->lock, flags);
1122 if (priv->current_status & CYP_ERROR) {
1123 spin_unlock_irqrestore(lock: &priv->lock, flags);
1124 tty_flag = TTY_PARITY;
1125 dev_dbg(dev, "%s - Parity Error detected\n", __func__);
1126 } else
1127 spin_unlock_irqrestore(lock: &priv->lock, flags);
1128
1129 /* process read if there is data other than line status */
1130 if (bytes > i) {
1131 tty_insert_flip_string_fixed_flag(port: &port->port, chars: data + i,
1132 flag: tty_flag, size: bytes - i);
1133 tty_flip_buffer_push(port: &port->port);
1134 }
1135
1136 spin_lock_irqsave(&priv->lock, flags);
1137 /* control and status byte(s) are also counted */
1138 priv->bytes_in += bytes;
1139 spin_unlock_irqrestore(lock: &priv->lock, flags);
1140
1141continue_read:
1142 tty_kref_put(tty);
1143
1144 /* Continue trying to always read */
1145
1146 if (priv->comm_is_ok) {
1147 usb_fill_int_urb(urb: port->interrupt_in_urb, dev: port->serial->dev,
1148 usb_rcvintpipe(port->serial->dev,
1149 port->interrupt_in_endpointAddress),
1150 transfer_buffer: port->interrupt_in_urb->transfer_buffer,
1151 buffer_length: port->interrupt_in_urb->transfer_buffer_length,
1152 complete_fn: cypress_read_int_callback, context: port,
1153 interval: priv->read_urb_interval);
1154 result = usb_submit_urb(urb: port->interrupt_in_urb, GFP_ATOMIC);
1155 if (result && result != -EPERM) {
1156 dev_err(dev, "%s - failed resubmitting read urb, error %d\n",
1157 __func__, result);
1158 cypress_set_dead(port);
1159 }
1160 }
1161} /* cypress_read_int_callback */
1162
1163
1164static void cypress_write_int_callback(struct urb *urb)
1165{
1166 struct usb_serial_port *port = urb->context;
1167 struct cypress_private *priv = usb_get_serial_port_data(port);
1168 struct device *dev = &urb->dev->dev;
1169 int status = urb->status;
1170
1171 switch (status) {
1172 case 0:
1173 /* success */
1174 break;
1175 case -ECONNRESET:
1176 case -ENOENT:
1177 case -ESHUTDOWN:
1178 /* this urb is terminated, clean up */
1179 dev_dbg(dev, "%s - urb shutting down with status: %d\n",
1180 __func__, status);
1181 priv->write_urb_in_use = 0;
1182 return;
1183 case -EPIPE:
1184 /* Cannot call usb_clear_halt while in_interrupt */
1185 fallthrough;
1186 default:
1187 dev_err(dev, "%s - unexpected nonzero write status received: %d\n",
1188 __func__, status);
1189 cypress_set_dead(port);
1190 break;
1191 }
1192 priv->write_urb_in_use = 0;
1193
1194 /* send any buffered data */
1195 cypress_send(port);
1196}
1197
1198module_usb_serial_driver(serial_drivers, id_table_combined);
1199
1200MODULE_AUTHOR(DRIVER_AUTHOR);
1201MODULE_DESCRIPTION(DRIVER_DESC);
1202MODULE_LICENSE("GPL");
1203
1204module_param(stats, bool, 0644);
1205MODULE_PARM_DESC(stats, "Enable statistics or not");
1206module_param(interval, int, 0644);
1207MODULE_PARM_DESC(interval, "Overrides interrupt interval");
1208module_param(unstable_bauds, bool, 0644);
1209MODULE_PARM_DESC(unstable_bauds, "Allow unstable baud rates");
1210

source code of linux/drivers/usb/serial/cypress_m8.c