xref: /openbmc/linux/drivers/usb/serial/kl5kusb105.c (revision 4f3db074)
1 /*
2  * KLSI KL5KUSB105 chip RS232 converter driver
3  *
4  *   Copyright (C) 2010 Johan Hovold <jhovold@gmail.com>
5  *   Copyright (C) 2001 Utz-Uwe Haus <haus@uuhaus.de>
6  *
7  *   This program is free software; you can redistribute it and/or modify
8  *   it under the terms of the GNU General Public License as published by
9  *   the Free Software Foundation; either version 2 of the License, or
10  *   (at your option) any later version.
11  *
12  * All information about the device was acquired using SniffUSB ans snoopUSB
13  * on Windows98.
14  * It was written out of frustration with the PalmConnect USB Serial adapter
15  * sold by Palm Inc.
16  * Neither Palm, nor their contractor (MCCI) or their supplier (KLSI) provided
17  * information that was not already available.
18  *
19  * It seems that KLSI bought some silicon-design information from ScanLogic,
20  * whose SL11R processor is at the core of the KL5KUSB chipset from KLSI.
21  * KLSI has firmware available for their devices; it is probable that the
22  * firmware differs from that used by KLSI in their products. If you have an
23  * original KLSI device and can provide some information on it, I would be
24  * most interested in adding support for it here. If you have any information
25  * on the protocol used (or find errors in my reverse-engineered stuff), please
26  * let me know.
27  *
28  * The code was only tested with a PalmConnect USB adapter; if you
29  * are adventurous, try it with any KLSI-based device and let me know how it
30  * breaks so that I can fix it!
31  */
32 
33 /* TODO:
34  *	check modem line signals
35  *	implement handshaking or decide that we do not support it
36  */
37 
38 #include <linux/kernel.h>
39 #include <linux/errno.h>
40 #include <linux/slab.h>
41 #include <linux/tty.h>
42 #include <linux/tty_driver.h>
43 #include <linux/tty_flip.h>
44 #include <linux/module.h>
45 #include <linux/uaccess.h>
46 #include <asm/unaligned.h>
47 #include <linux/usb.h>
48 #include <linux/usb/serial.h>
49 #include "kl5kusb105.h"
50 
51 #define DRIVER_AUTHOR "Utz-Uwe Haus <haus@uuhaus.de>, Johan Hovold <jhovold@gmail.com>"
52 #define DRIVER_DESC "KLSI KL5KUSB105 chipset USB->Serial Converter driver"
53 
54 
55 /*
56  * Function prototypes
57  */
58 static int klsi_105_port_probe(struct usb_serial_port *port);
59 static int klsi_105_port_remove(struct usb_serial_port *port);
60 static int  klsi_105_open(struct tty_struct *tty, struct usb_serial_port *port);
61 static void klsi_105_close(struct usb_serial_port *port);
62 static void klsi_105_set_termios(struct tty_struct *tty,
63 			struct usb_serial_port *port, struct ktermios *old);
64 static int  klsi_105_tiocmget(struct tty_struct *tty);
65 static void klsi_105_process_read_urb(struct urb *urb);
66 static int klsi_105_prepare_write_buffer(struct usb_serial_port *port,
67 						void *dest, size_t size);
68 
69 /*
70  * All of the device info needed for the KLSI converters.
71  */
72 static const struct usb_device_id id_table[] = {
73 	{ USB_DEVICE(PALMCONNECT_VID, PALMCONNECT_PID) },
74 	{ USB_DEVICE(KLSI_VID, KLSI_KL5KUSB105D_PID) },
75 	{ }		/* Terminating entry */
76 };
77 
78 MODULE_DEVICE_TABLE(usb, id_table);
79 
80 static struct usb_serial_driver kl5kusb105d_device = {
81 	.driver = {
82 		.owner =	THIS_MODULE,
83 		.name =		"kl5kusb105d",
84 	},
85 	.description =		"KL5KUSB105D / PalmConnect",
86 	.id_table =		id_table,
87 	.num_ports =		1,
88 	.bulk_out_size =	64,
89 	.open =			klsi_105_open,
90 	.close =		klsi_105_close,
91 	.set_termios =		klsi_105_set_termios,
92 	/*.break_ctl =		klsi_105_break_ctl,*/
93 	.tiocmget =		klsi_105_tiocmget,
94 	.port_probe =		klsi_105_port_probe,
95 	.port_remove =		klsi_105_port_remove,
96 	.throttle =		usb_serial_generic_throttle,
97 	.unthrottle =		usb_serial_generic_unthrottle,
98 	.process_read_urb =	klsi_105_process_read_urb,
99 	.prepare_write_buffer =	klsi_105_prepare_write_buffer,
100 };
101 
102 static struct usb_serial_driver * const serial_drivers[] = {
103 	&kl5kusb105d_device, NULL
104 };
105 
106 struct klsi_105_port_settings {
107 	__u8	pktlen;		/* always 5, it seems */
108 	__u8	baudrate;
109 	__u8	databits;
110 	__u8	unknown1;
111 	__u8	unknown2;
112 } __attribute__ ((packed));
113 
114 struct klsi_105_private {
115 	struct klsi_105_port_settings	cfg;
116 	struct ktermios			termios;
117 	unsigned long			line_state; /* modem line settings */
118 	spinlock_t			lock;
119 };
120 
121 
122 /*
123  * Handle vendor specific USB requests
124  */
125 
126 
127 #define KLSI_TIMEOUT	 5000 /* default urb timeout */
128 
129 static int klsi_105_chg_port_settings(struct usb_serial_port *port,
130 				      struct klsi_105_port_settings *settings)
131 {
132 	int rc;
133 
134 	rc = usb_control_msg(port->serial->dev,
135 			usb_sndctrlpipe(port->serial->dev, 0),
136 			KL5KUSB105A_SIO_SET_DATA,
137 			USB_TYPE_VENDOR | USB_DIR_OUT | USB_RECIP_INTERFACE,
138 			0, /* value */
139 			0, /* index */
140 			settings,
141 			sizeof(struct klsi_105_port_settings),
142 			KLSI_TIMEOUT);
143 	if (rc < 0)
144 		dev_err(&port->dev,
145 			"Change port settings failed (error = %d)\n", rc);
146 	dev_info(&port->serial->dev->dev,
147 		 "%d byte block, baudrate %x, databits %d, u1 %d, u2 %d\n",
148 		 settings->pktlen, settings->baudrate, settings->databits,
149 		 settings->unknown1, settings->unknown2);
150 	return rc;
151 }
152 
153 /* translate a 16-bit status value from the device to linux's TIO bits */
154 static unsigned long klsi_105_status2linestate(const __u16 status)
155 {
156 	unsigned long res = 0;
157 
158 	res =   ((status & KL5KUSB105A_DSR) ? TIOCM_DSR : 0)
159 	      | ((status & KL5KUSB105A_CTS) ? TIOCM_CTS : 0)
160 	      ;
161 
162 	return res;
163 }
164 
165 /*
166  * Read line control via vendor command and return result through
167  * *line_state_p
168  */
169 /* It seems that the status buffer has always only 2 bytes length */
170 #define KLSI_STATUSBUF_LEN	2
171 static int klsi_105_get_line_state(struct usb_serial_port *port,
172 				   unsigned long *line_state_p)
173 {
174 	int rc;
175 	u8 *status_buf;
176 	__u16 status;
177 
178 	dev_info(&port->serial->dev->dev, "sending SIO Poll request\n");
179 
180 	status_buf = kmalloc(KLSI_STATUSBUF_LEN, GFP_KERNEL);
181 	if (!status_buf)
182 		return -ENOMEM;
183 
184 	status_buf[0] = 0xff;
185 	status_buf[1] = 0xff;
186 	rc = usb_control_msg(port->serial->dev,
187 			     usb_rcvctrlpipe(port->serial->dev, 0),
188 			     KL5KUSB105A_SIO_POLL,
189 			     USB_TYPE_VENDOR | USB_DIR_IN,
190 			     0, /* value */
191 			     0, /* index */
192 			     status_buf, KLSI_STATUSBUF_LEN,
193 			     10000
194 			     );
195 	if (rc < 0)
196 		dev_err(&port->dev, "Reading line status failed (error = %d)\n",
197 			rc);
198 	else {
199 		status = get_unaligned_le16(status_buf);
200 
201 		dev_info(&port->serial->dev->dev, "read status %x %x\n",
202 			 status_buf[0], status_buf[1]);
203 
204 		*line_state_p = klsi_105_status2linestate(status);
205 	}
206 
207 	kfree(status_buf);
208 	return rc;
209 }
210 
211 
212 /*
213  * Driver's tty interface functions
214  */
215 
216 static int klsi_105_port_probe(struct usb_serial_port *port)
217 {
218 	struct klsi_105_private *priv;
219 
220 	priv = kmalloc(sizeof(*priv), GFP_KERNEL);
221 	if (!priv)
222 		return -ENOMEM;
223 
224 	/* set initial values for control structures */
225 	priv->cfg.pktlen    = 5;
226 	priv->cfg.baudrate  = kl5kusb105a_sio_b9600;
227 	priv->cfg.databits  = kl5kusb105a_dtb_8;
228 	priv->cfg.unknown1  = 0;
229 	priv->cfg.unknown2  = 1;
230 
231 	priv->line_state    = 0;
232 
233 	spin_lock_init(&priv->lock);
234 
235 	/* priv->termios is left uninitialized until port opening */
236 
237 	usb_set_serial_port_data(port, priv);
238 
239 	return 0;
240 }
241 
242 static int klsi_105_port_remove(struct usb_serial_port *port)
243 {
244 	struct klsi_105_private *priv;
245 
246 	priv = usb_get_serial_port_data(port);
247 	kfree(priv);
248 
249 	return 0;
250 }
251 
252 static int  klsi_105_open(struct tty_struct *tty, struct usb_serial_port *port)
253 {
254 	struct klsi_105_private *priv = usb_get_serial_port_data(port);
255 	int retval = 0;
256 	int rc;
257 	int i;
258 	unsigned long line_state;
259 	struct klsi_105_port_settings *cfg;
260 	unsigned long flags;
261 
262 	/* Do a defined restart:
263 	 * Set up sane default baud rate and send the 'READ_ON'
264 	 * vendor command.
265 	 * FIXME: set modem line control (how?)
266 	 * Then read the modem line control and store values in
267 	 * priv->line_state.
268 	 */
269 	cfg = kmalloc(sizeof(*cfg), GFP_KERNEL);
270 	if (!cfg)
271 		return -ENOMEM;
272 
273 	cfg->pktlen   = 5;
274 	cfg->baudrate = kl5kusb105a_sio_b9600;
275 	cfg->databits = kl5kusb105a_dtb_8;
276 	cfg->unknown1 = 0;
277 	cfg->unknown2 = 1;
278 	klsi_105_chg_port_settings(port, cfg);
279 
280 	/* set up termios structure */
281 	spin_lock_irqsave(&priv->lock, flags);
282 	priv->termios.c_iflag = tty->termios.c_iflag;
283 	priv->termios.c_oflag = tty->termios.c_oflag;
284 	priv->termios.c_cflag = tty->termios.c_cflag;
285 	priv->termios.c_lflag = tty->termios.c_lflag;
286 	for (i = 0; i < NCCS; i++)
287 		priv->termios.c_cc[i] = tty->termios.c_cc[i];
288 	priv->cfg.pktlen   = cfg->pktlen;
289 	priv->cfg.baudrate = cfg->baudrate;
290 	priv->cfg.databits = cfg->databits;
291 	priv->cfg.unknown1 = cfg->unknown1;
292 	priv->cfg.unknown2 = cfg->unknown2;
293 	spin_unlock_irqrestore(&priv->lock, flags);
294 
295 	/* READ_ON and urb submission */
296 	rc = usb_serial_generic_open(tty, port);
297 	if (rc) {
298 		retval = rc;
299 		goto exit;
300 	}
301 
302 	rc = usb_control_msg(port->serial->dev,
303 			     usb_sndctrlpipe(port->serial->dev, 0),
304 			     KL5KUSB105A_SIO_CONFIGURE,
305 			     USB_TYPE_VENDOR|USB_DIR_OUT|USB_RECIP_INTERFACE,
306 			     KL5KUSB105A_SIO_CONFIGURE_READ_ON,
307 			     0, /* index */
308 			     NULL,
309 			     0,
310 			     KLSI_TIMEOUT);
311 	if (rc < 0) {
312 		dev_err(&port->dev, "Enabling read failed (error = %d)\n", rc);
313 		retval = rc;
314 	} else
315 		dev_dbg(&port->dev, "%s - enabled reading\n", __func__);
316 
317 	rc = klsi_105_get_line_state(port, &line_state);
318 	if (rc >= 0) {
319 		spin_lock_irqsave(&priv->lock, flags);
320 		priv->line_state = line_state;
321 		spin_unlock_irqrestore(&priv->lock, flags);
322 		dev_dbg(&port->dev, "%s - read line state 0x%lx\n", __func__, line_state);
323 		retval = 0;
324 	} else
325 		retval = rc;
326 
327 exit:
328 	kfree(cfg);
329 	return retval;
330 }
331 
332 static void klsi_105_close(struct usb_serial_port *port)
333 {
334 	int rc;
335 
336 	/* send READ_OFF */
337 	rc = usb_control_msg(port->serial->dev,
338 			     usb_sndctrlpipe(port->serial->dev, 0),
339 			     KL5KUSB105A_SIO_CONFIGURE,
340 			     USB_TYPE_VENDOR | USB_DIR_OUT,
341 			     KL5KUSB105A_SIO_CONFIGURE_READ_OFF,
342 			     0, /* index */
343 			     NULL, 0,
344 			     KLSI_TIMEOUT);
345 	if (rc < 0)
346 		dev_err(&port->dev, "failed to disable read: %d\n", rc);
347 
348 	/* shutdown our bulk reads and writes */
349 	usb_serial_generic_close(port);
350 }
351 
352 /* We need to write a complete 64-byte data block and encode the
353  * number actually sent in the first double-byte, LSB-order. That
354  * leaves at most 62 bytes of payload.
355  */
356 #define KLSI_HDR_LEN		2
357 static int klsi_105_prepare_write_buffer(struct usb_serial_port *port,
358 						void *dest, size_t size)
359 {
360 	unsigned char *buf = dest;
361 	int count;
362 
363 	count = kfifo_out_locked(&port->write_fifo, buf + KLSI_HDR_LEN, size,
364 								&port->lock);
365 	put_unaligned_le16(count, buf);
366 
367 	return count + KLSI_HDR_LEN;
368 }
369 
370 /* The data received is preceded by a length double-byte in LSB-first order.
371  */
372 static void klsi_105_process_read_urb(struct urb *urb)
373 {
374 	struct usb_serial_port *port = urb->context;
375 	unsigned char *data = urb->transfer_buffer;
376 	unsigned len;
377 
378 	/* empty urbs seem to happen, we ignore them */
379 	if (!urb->actual_length)
380 		return;
381 
382 	if (urb->actual_length <= KLSI_HDR_LEN) {
383 		dev_dbg(&port->dev, "%s - malformed packet\n", __func__);
384 		return;
385 	}
386 
387 	len = get_unaligned_le16(data);
388 	if (len > urb->actual_length - KLSI_HDR_LEN) {
389 		dev_dbg(&port->dev, "%s - packet length mismatch\n", __func__);
390 		len = urb->actual_length - KLSI_HDR_LEN;
391 	}
392 
393 	tty_insert_flip_string(&port->port, data + KLSI_HDR_LEN, len);
394 	tty_flip_buffer_push(&port->port);
395 }
396 
397 static void klsi_105_set_termios(struct tty_struct *tty,
398 				 struct usb_serial_port *port,
399 				 struct ktermios *old_termios)
400 {
401 	struct klsi_105_private *priv = usb_get_serial_port_data(port);
402 	struct device *dev = &port->dev;
403 	unsigned int iflag = tty->termios.c_iflag;
404 	unsigned int old_iflag = old_termios->c_iflag;
405 	unsigned int cflag = tty->termios.c_cflag;
406 	unsigned int old_cflag = old_termios->c_cflag;
407 	struct klsi_105_port_settings *cfg;
408 	unsigned long flags;
409 	speed_t baud;
410 
411 	cfg = kmalloc(sizeof(*cfg), GFP_KERNEL);
412 	if (!cfg)
413 		return;
414 
415 	/* lock while we are modifying the settings */
416 	spin_lock_irqsave(&priv->lock, flags);
417 
418 	/*
419 	 * Update baud rate
420 	 */
421 	baud = tty_get_baud_rate(tty);
422 
423 	if ((cflag & CBAUD) != (old_cflag & CBAUD)) {
424 		/* reassert DTR and (maybe) RTS on transition from B0 */
425 		if ((old_cflag & CBAUD) == B0) {
426 			dev_dbg(dev, "%s: baud was B0\n", __func__);
427 #if 0
428 			priv->control_state |= TIOCM_DTR;
429 			/* don't set RTS if using hardware flow control */
430 			if (!(old_cflag & CRTSCTS))
431 				priv->control_state |= TIOCM_RTS;
432 			mct_u232_set_modem_ctrl(serial, priv->control_state);
433 #endif
434 		}
435 	}
436 	switch (baud) {
437 	case 0: /* handled below */
438 		break;
439 	case 1200:
440 		priv->cfg.baudrate = kl5kusb105a_sio_b1200;
441 		break;
442 	case 2400:
443 		priv->cfg.baudrate = kl5kusb105a_sio_b2400;
444 		break;
445 	case 4800:
446 		priv->cfg.baudrate = kl5kusb105a_sio_b4800;
447 		break;
448 	case 9600:
449 		priv->cfg.baudrate = kl5kusb105a_sio_b9600;
450 		break;
451 	case 19200:
452 		priv->cfg.baudrate = kl5kusb105a_sio_b19200;
453 		break;
454 	case 38400:
455 		priv->cfg.baudrate = kl5kusb105a_sio_b38400;
456 		break;
457 	case 57600:
458 		priv->cfg.baudrate = kl5kusb105a_sio_b57600;
459 		break;
460 	case 115200:
461 		priv->cfg.baudrate = kl5kusb105a_sio_b115200;
462 		break;
463 	default:
464 		dev_dbg(dev, "unsupported baudrate, using 9600\n");
465 		priv->cfg.baudrate = kl5kusb105a_sio_b9600;
466 		baud = 9600;
467 		break;
468 	}
469 	if ((cflag & CBAUD) == B0) {
470 		dev_dbg(dev, "%s: baud is B0\n", __func__);
471 		/* Drop RTS and DTR */
472 		/* maybe this should be simulated by sending read
473 		 * disable and read enable messages?
474 		 */
475 		;
476 #if 0
477 		priv->control_state &= ~(TIOCM_DTR | TIOCM_RTS);
478 		mct_u232_set_modem_ctrl(serial, priv->control_state);
479 #endif
480 	}
481 	tty_encode_baud_rate(tty, baud, baud);
482 
483 	if ((cflag & CSIZE) != (old_cflag & CSIZE)) {
484 		/* set the number of data bits */
485 		switch (cflag & CSIZE) {
486 		case CS5:
487 			dev_dbg(dev, "%s - 5 bits/byte not supported\n", __func__);
488 			spin_unlock_irqrestore(&priv->lock, flags);
489 			goto err;
490 		case CS6:
491 			dev_dbg(dev, "%s - 6 bits/byte not supported\n", __func__);
492 			spin_unlock_irqrestore(&priv->lock, flags);
493 			goto err;
494 		case CS7:
495 			priv->cfg.databits = kl5kusb105a_dtb_7;
496 			break;
497 		case CS8:
498 			priv->cfg.databits = kl5kusb105a_dtb_8;
499 			break;
500 		default:
501 			dev_err(dev, "CSIZE was not CS5-CS8, using default of 8\n");
502 			priv->cfg.databits = kl5kusb105a_dtb_8;
503 			break;
504 		}
505 	}
506 
507 	/*
508 	 * Update line control register (LCR)
509 	 */
510 	if ((cflag & (PARENB|PARODD)) != (old_cflag & (PARENB|PARODD))
511 	    || (cflag & CSTOPB) != (old_cflag & CSTOPB)) {
512 		/* Not currently supported */
513 		tty->termios.c_cflag &= ~(PARENB|PARODD|CSTOPB);
514 #if 0
515 		priv->last_lcr = 0;
516 
517 		/* set the parity */
518 		if (cflag & PARENB)
519 			priv->last_lcr |= (cflag & PARODD) ?
520 				MCT_U232_PARITY_ODD : MCT_U232_PARITY_EVEN;
521 		else
522 			priv->last_lcr |= MCT_U232_PARITY_NONE;
523 
524 		/* set the number of stop bits */
525 		priv->last_lcr |= (cflag & CSTOPB) ?
526 			MCT_U232_STOP_BITS_2 : MCT_U232_STOP_BITS_1;
527 
528 		mct_u232_set_line_ctrl(serial, priv->last_lcr);
529 #endif
530 		;
531 	}
532 	/*
533 	 * Set flow control: well, I do not really now how to handle DTR/RTS.
534 	 * Just do what we have seen with SniffUSB on Win98.
535 	 */
536 	if ((iflag & IXOFF) != (old_iflag & IXOFF)
537 	    || (iflag & IXON) != (old_iflag & IXON)
538 	    ||  (cflag & CRTSCTS) != (old_cflag & CRTSCTS)) {
539 		/* Not currently supported */
540 		tty->termios.c_cflag &= ~CRTSCTS;
541 		/* Drop DTR/RTS if no flow control otherwise assert */
542 #if 0
543 		if ((iflag & IXOFF) || (iflag & IXON) || (cflag & CRTSCTS))
544 			priv->control_state |= TIOCM_DTR | TIOCM_RTS;
545 		else
546 			priv->control_state &= ~(TIOCM_DTR | TIOCM_RTS);
547 		mct_u232_set_modem_ctrl(serial, priv->control_state);
548 #endif
549 		;
550 	}
551 	memcpy(cfg, &priv->cfg, sizeof(*cfg));
552 	spin_unlock_irqrestore(&priv->lock, flags);
553 
554 	/* now commit changes to device */
555 	klsi_105_chg_port_settings(port, cfg);
556 err:
557 	kfree(cfg);
558 }
559 
560 #if 0
561 static void mct_u232_break_ctl(struct tty_struct *tty, int break_state)
562 {
563 	struct usb_serial_port *port = tty->driver_data;
564 	struct usb_serial *serial = port->serial;
565 	struct mct_u232_private *priv =
566 				(struct mct_u232_private *)port->private;
567 	unsigned char lcr = priv->last_lcr;
568 
569 	dev_dbg(&port->dev, "%s - state=%d\n", __func__, break_state);
570 
571 	/* LOCKING */
572 	if (break_state)
573 		lcr |= MCT_U232_SET_BREAK;
574 
575 	mct_u232_set_line_ctrl(serial, lcr);
576 }
577 #endif
578 
579 static int klsi_105_tiocmget(struct tty_struct *tty)
580 {
581 	struct usb_serial_port *port = tty->driver_data;
582 	struct klsi_105_private *priv = usb_get_serial_port_data(port);
583 	unsigned long flags;
584 	int rc;
585 	unsigned long line_state;
586 
587 	rc = klsi_105_get_line_state(port, &line_state);
588 	if (rc < 0) {
589 		dev_err(&port->dev,
590 			"Reading line control failed (error = %d)\n", rc);
591 		/* better return value? EAGAIN? */
592 		return rc;
593 	}
594 
595 	spin_lock_irqsave(&priv->lock, flags);
596 	priv->line_state = line_state;
597 	spin_unlock_irqrestore(&priv->lock, flags);
598 	dev_dbg(&port->dev, "%s - read line state 0x%lx\n", __func__, line_state);
599 	return (int)line_state;
600 }
601 
602 module_usb_serial_driver(serial_drivers, id_table);
603 
604 MODULE_AUTHOR(DRIVER_AUTHOR);
605 MODULE_DESCRIPTION(DRIVER_DESC);
606 MODULE_LICENSE("GPL");
607