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v3.1
  1/*
  2 * Belkin USB Serial Adapter Driver
  3 *
  4 *  Copyright (C) 2000		William Greathouse (wgreathouse@smva.com)
  5 *  Copyright (C) 2000-2001 	Greg Kroah-Hartman (greg@kroah.com)
  6 *  Copyright (C) 2010		Johan Hovold (jhovold@gmail.com)
  7 *
  8 *  This program is largely derived from work by the linux-usb group
  9 *  and associated source files.  Please see the usb/serial files for
 10 *  individual credits and copyrights.
 11 *
 12 * 	This program is free software; you can redistribute it and/or modify
 13 * 	it under the terms of the GNU General Public License as published by
 14 * 	the Free Software Foundation; either version 2 of the License, or
 15 * 	(at your option) any later version.
 16 *
 17 * See Documentation/usb/usb-serial.txt for more information on using this
 18 * driver
 19 *
 20 * TODO:
 21 * -- Add true modem contol line query capability.  Currently we track the
 22 *    states reported by the interrupt and the states we request.
 23 * -- Add error reporting back to application for UART error conditions.
 24 *    Just point me at how to implement this and I'll do it. I've put the
 25 *    framework in, but haven't analyzed the "tty_flip" interface yet.
 26 * -- Add support for flush commands
 27 * -- Add everything that is missing :)
 28 *
 29 * 27-Nov-2001 gkh
 30 * 	compressed all the differnent device entries into 1.
 31 *
 32 * 30-May-2001 gkh
 33 *	switched from using spinlock to a semaphore, which fixes lots of
 34 *	problems.
 35 *
 36 * 08-Apr-2001 gb
 37 *	- Identify version on module load.
 38 *
 39 * 12-Mar-2001 gkh
 40 *	- Added support for the GoHubs GO-COM232 device which is the same as the
 41 *	  Peracom device.
 42 *
 43 * 06-Nov-2000 gkh
 44 *	- Added support for the old Belkin and Peracom devices.
 45 *	- Made the port able to be opened multiple times.
 46 *	- Added some defaults incase the line settings are things these devices
 47 *	  can't support.
 48 *
 49 * 18-Oct-2000 William Greathouse
 50 *    Released into the wild (linux-usb-devel)
 51 *
 52 * 17-Oct-2000 William Greathouse
 53 *    Add code to recognize firmware version and set hardware flow control
 54 *    appropriately.  Belkin states that firmware prior to 3.05 does not
 55 *    operate correctly in hardware handshake mode.  I have verified this
 56 *    on firmware 2.05 -- for both RTS and DTR input flow control, the control
 57 *    line is not reset.  The test performed by the Belkin Win* driver is
 58 *    to enable hardware flow control for firmware 2.06 or greater and
 59 *    for 1.00 or prior.  I am only enabling for 2.06 or greater.
 60 *
 61 * 12-Oct-2000 William Greathouse
 62 *    First cut at supporting Belkin USB Serial Adapter F5U103
 63 *    I did not have a copy of the original work to support this
 64 *    adapter, so pardon any stupid mistakes.  All of the information
 65 *    I am using to write this driver was acquired by using a modified
 66 *    UsbSnoop on Windows2000 and from examining the other USB drivers.
 67 */
 68
 69#include <linux/kernel.h>
 70#include <linux/errno.h>
 71#include <linux/init.h>
 72#include <linux/slab.h>
 73#include <linux/tty.h>
 74#include <linux/tty_driver.h>
 75#include <linux/tty_flip.h>
 76#include <linux/module.h>
 77#include <linux/spinlock.h>
 78#include <linux/uaccess.h>
 79#include <linux/usb.h>
 80#include <linux/usb/serial.h>
 81#include "belkin_sa.h"
 82
 83static int debug;
 84
 85/*
 86 * Version Information
 87 */
 88#define DRIVER_VERSION "v1.3"
 89#define DRIVER_AUTHOR "William Greathouse <wgreathouse@smva.com>"
 90#define DRIVER_DESC "USB Belkin Serial converter driver"
 91
 92/* function prototypes for a Belkin USB Serial Adapter F5U103 */
 93static int  belkin_sa_startup(struct usb_serial *serial);
 94static void belkin_sa_release(struct usb_serial *serial);
 95static int  belkin_sa_open(struct tty_struct *tty,
 96			struct usb_serial_port *port);
 97static void belkin_sa_close(struct usb_serial_port *port);
 98static void belkin_sa_read_int_callback(struct urb *urb);
 99static void belkin_sa_process_read_urb(struct urb *urb);
100static void belkin_sa_set_termios(struct tty_struct *tty,
101			struct usb_serial_port *port, struct ktermios * old);
102static void belkin_sa_break_ctl(struct tty_struct *tty, int break_state);
103static int  belkin_sa_tiocmget(struct tty_struct *tty);
104static int  belkin_sa_tiocmset(struct tty_struct *tty,
105					unsigned int set, unsigned int clear);
106
107
108static const struct usb_device_id id_table_combined[] = {
109	{ USB_DEVICE(BELKIN_SA_VID, BELKIN_SA_PID) },
110	{ USB_DEVICE(BELKIN_OLD_VID, BELKIN_OLD_PID) },
111	{ USB_DEVICE(PERACOM_VID, PERACOM_PID) },
112	{ USB_DEVICE(GOHUBS_VID, GOHUBS_PID) },
113	{ USB_DEVICE(GOHUBS_VID, HANDYLINK_PID) },
114	{ USB_DEVICE(BELKIN_DOCKSTATION_VID, BELKIN_DOCKSTATION_PID) },
115	{ }	/* Terminating entry */
116};
117MODULE_DEVICE_TABLE(usb, id_table_combined);
118
119static struct usb_driver belkin_driver = {
120	.name =		"belkin",
121	.probe =	usb_serial_probe,
122	.disconnect =	usb_serial_disconnect,
123	.id_table =	id_table_combined,
124	.no_dynamic_id =	1,
125};
126
127/* All of the device info needed for the serial converters */
128static struct usb_serial_driver belkin_device = {
129	.driver = {
130		.owner =	THIS_MODULE,
131		.name =		"belkin",
132	},
133	.description =		"Belkin / Peracom / GoHubs USB Serial Adapter",
134	.usb_driver =		&belkin_driver,
135	.id_table =		id_table_combined,
136	.num_ports =		1,
137	.open =			belkin_sa_open,
138	.close =		belkin_sa_close,
139	.read_int_callback =	belkin_sa_read_int_callback,
140	.process_read_urb =	belkin_sa_process_read_urb,
141	.set_termios =		belkin_sa_set_termios,
142	.break_ctl =		belkin_sa_break_ctl,
143	.tiocmget =		belkin_sa_tiocmget,
144	.tiocmset =		belkin_sa_tiocmset,
145	.attach =		belkin_sa_startup,
146	.release =		belkin_sa_release,
 
 
 
 
147};
148
149struct belkin_sa_private {
150	spinlock_t		lock;
151	unsigned long		control_state;
152	unsigned char		last_lsr;
153	unsigned char		last_msr;
154	int			bad_flow_control;
155};
156
157
158/*
159 * ***************************************************************************
160 * Belkin USB Serial Adapter F5U103 specific driver functions
161 * ***************************************************************************
162 */
163
164#define WDR_TIMEOUT 5000 /* default urb timeout */
165
166/* assumes that struct usb_serial *serial is available */
167#define BSA_USB_CMD(c, v) usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0), \
168					    (c), BELKIN_SA_SET_REQUEST_TYPE, \
169					    (v), 0, NULL, 0, WDR_TIMEOUT)
170
171/* do some startup allocations not currently performed by usb_serial_probe() */
172static int belkin_sa_startup(struct usb_serial *serial)
173{
174	struct usb_device *dev = serial->dev;
175	struct belkin_sa_private *priv;
176
177	/* allocate the private data structure */
178	priv = kmalloc(sizeof(struct belkin_sa_private), GFP_KERNEL);
179	if (!priv)
180		return -1; /* error */
181	/* set initial values for control structures */
182	spin_lock_init(&priv->lock);
183	priv->control_state = 0;
184	priv->last_lsr = 0;
185	priv->last_msr = 0;
186	/* see comments at top of file */
187	priv->bad_flow_control =
188		(le16_to_cpu(dev->descriptor.bcdDevice) <= 0x0206) ? 1 : 0;
189	dev_info(&dev->dev, "bcdDevice: %04x, bfc: %d\n",
190					le16_to_cpu(dev->descriptor.bcdDevice),
191					priv->bad_flow_control);
192
193	init_waitqueue_head(&serial->port[0]->write_wait);
194	usb_set_serial_port_data(serial->port[0], priv);
195
196	return 0;
197}
198
199static void belkin_sa_release(struct usb_serial *serial)
200{
201	int i;
202
203	dbg("%s", __func__);
 
204
205	for (i = 0; i < serial->num_ports; ++i)
206		kfree(usb_get_serial_port_data(serial->port[i]));
207}
208
209static int belkin_sa_open(struct tty_struct *tty,
210					struct usb_serial_port *port)
211{
212	int retval;
213
214	dbg("%s port %d", __func__, port->number);
215
216	retval = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
217	if (retval) {
218		dev_err(&port->dev, "usb_submit_urb(read int) failed\n");
219		return retval;
220	}
221
222	retval = usb_serial_generic_open(tty, port);
223	if (retval)
224		usb_kill_urb(port->interrupt_in_urb);
225
226	return retval;
227}
228
229static void belkin_sa_close(struct usb_serial_port *port)
230{
231	dbg("%s port %d", __func__, port->number);
232
233	usb_serial_generic_close(port);
234	usb_kill_urb(port->interrupt_in_urb);
235}
236
237static void belkin_sa_read_int_callback(struct urb *urb)
238{
239	struct usb_serial_port *port = urb->context;
240	struct belkin_sa_private *priv;
241	unsigned char *data = urb->transfer_buffer;
242	int retval;
243	int status = urb->status;
244	unsigned long flags;
245
246	switch (status) {
247	case 0:
248		/* success */
249		break;
250	case -ECONNRESET:
251	case -ENOENT:
252	case -ESHUTDOWN:
253		/* this urb is terminated, clean up */
254		dbg("%s - urb shutting down with status: %d",
255		    __func__, status);
256		return;
257	default:
258		dbg("%s - nonzero urb status received: %d",
259		    __func__, status);
260		goto exit;
261	}
262
263	usb_serial_debug_data(debug, &port->dev, __func__,
264					urb->actual_length, data);
265
266	/* Handle known interrupt data */
267	/* ignore data[0] and data[1] */
268
269	priv = usb_get_serial_port_data(port);
270	spin_lock_irqsave(&priv->lock, flags);
271	priv->last_msr = data[BELKIN_SA_MSR_INDEX];
272
273	/* Record Control Line states */
274	if (priv->last_msr & BELKIN_SA_MSR_DSR)
275		priv->control_state |= TIOCM_DSR;
276	else
277		priv->control_state &= ~TIOCM_DSR;
278
279	if (priv->last_msr & BELKIN_SA_MSR_CTS)
280		priv->control_state |= TIOCM_CTS;
281	else
282		priv->control_state &= ~TIOCM_CTS;
283
284	if (priv->last_msr & BELKIN_SA_MSR_RI)
285		priv->control_state |= TIOCM_RI;
286	else
287		priv->control_state &= ~TIOCM_RI;
288
289	if (priv->last_msr & BELKIN_SA_MSR_CD)
290		priv->control_state |= TIOCM_CD;
291	else
292		priv->control_state &= ~TIOCM_CD;
293
294	priv->last_lsr = data[BELKIN_SA_LSR_INDEX];
295	spin_unlock_irqrestore(&priv->lock, flags);
296exit:
297	retval = usb_submit_urb(urb, GFP_ATOMIC);
298	if (retval)
299		dev_err(&port->dev, "%s - usb_submit_urb failed with "
300			"result %d\n", __func__, retval);
301}
302
303static void belkin_sa_process_read_urb(struct urb *urb)
304{
305	struct usb_serial_port *port = urb->context;
306	struct belkin_sa_private *priv = usb_get_serial_port_data(port);
307	struct tty_struct *tty;
308	unsigned char *data = urb->transfer_buffer;
309	unsigned long flags;
310	unsigned char status;
311	char tty_flag;
312
313	/* Update line status */
314	tty_flag = TTY_NORMAL;
315
316	spin_lock_irqsave(&priv->lock, flags);
317	status = priv->last_lsr;
318	priv->last_lsr &= ~BELKIN_SA_LSR_ERR;
319	spin_unlock_irqrestore(&priv->lock, flags);
320
321	if (!urb->actual_length)
322		return;
323
324	tty = tty_port_tty_get(&port->port);
325	if (!tty)
326		return;
327
328	if (status & BELKIN_SA_LSR_ERR) {
329		/* Break takes precedence over parity, which takes precedence
330		 * over framing errors. */
331		if (status & BELKIN_SA_LSR_BI)
332			tty_flag = TTY_BREAK;
333		else if (status & BELKIN_SA_LSR_PE)
334			tty_flag = TTY_PARITY;
335		else if (status & BELKIN_SA_LSR_FE)
336			tty_flag = TTY_FRAME;
337		dev_dbg(&port->dev, "tty_flag = %d\n", tty_flag);
338
339		/* Overrun is special, not associated with a char. */
340		if (status & BELKIN_SA_LSR_OE)
341			tty_insert_flip_char(tty, 0, TTY_OVERRUN);
342	}
343
344	tty_insert_flip_string_fixed_flag(tty, data, tty_flag,
345							urb->actual_length);
346	tty_flip_buffer_push(tty);
347	tty_kref_put(tty);
348}
349
350static void belkin_sa_set_termios(struct tty_struct *tty,
351		struct usb_serial_port *port, struct ktermios *old_termios)
352{
353	struct usb_serial *serial = port->serial;
354	struct belkin_sa_private *priv = usb_get_serial_port_data(port);
355	unsigned int iflag;
356	unsigned int cflag;
357	unsigned int old_iflag = 0;
358	unsigned int old_cflag = 0;
359	__u16 urb_value = 0; /* Will hold the new flags */
360	unsigned long flags;
361	unsigned long control_state;
362	int bad_flow_control;
363	speed_t baud;
364	struct ktermios *termios = tty->termios;
365
366	iflag = termios->c_iflag;
367	cflag = termios->c_cflag;
368
369	termios->c_cflag &= ~CMSPAR;
370
371	/* get a local copy of the current port settings */
372	spin_lock_irqsave(&priv->lock, flags);
373	control_state = priv->control_state;
374	bad_flow_control = priv->bad_flow_control;
375	spin_unlock_irqrestore(&priv->lock, flags);
376
377	old_iflag = old_termios->c_iflag;
378	old_cflag = old_termios->c_cflag;
379
380	/* Set the baud rate */
381	if ((cflag & CBAUD) != (old_cflag & CBAUD)) {
382		/* reassert DTR and (maybe) RTS on transition from B0 */
383		if ((old_cflag & CBAUD) == B0) {
384			control_state |= (TIOCM_DTR|TIOCM_RTS);
385			if (BSA_USB_CMD(BELKIN_SA_SET_DTR_REQUEST, 1) < 0)
386				dev_err(&port->dev, "Set DTR error\n");
387			/* don't set RTS if using hardware flow control */
388			if (!(old_cflag & CRTSCTS))
389				if (BSA_USB_CMD(BELKIN_SA_SET_RTS_REQUEST
390								, 1) < 0)
391					dev_err(&port->dev, "Set RTS error\n");
392		}
393	}
394
395	baud = tty_get_baud_rate(tty);
396	if (baud) {
397		urb_value = BELKIN_SA_BAUD(baud);
398		/* Clip to maximum speed */
399		if (urb_value == 0)
400			urb_value = 1;
401		/* Turn it back into a resulting real baud rate */
402		baud = BELKIN_SA_BAUD(urb_value);
403
404		/* Report the actual baud rate back to the caller */
405		tty_encode_baud_rate(tty, baud, baud);
406		if (BSA_USB_CMD(BELKIN_SA_SET_BAUDRATE_REQUEST, urb_value) < 0)
407			dev_err(&port->dev, "Set baudrate error\n");
408	} else {
409		/* Disable flow control */
410		if (BSA_USB_CMD(BELKIN_SA_SET_FLOW_CTRL_REQUEST,
411						BELKIN_SA_FLOW_NONE) < 0)
412			dev_err(&port->dev, "Disable flowcontrol error\n");
413		/* Drop RTS and DTR */
414		control_state &= ~(TIOCM_DTR | TIOCM_RTS);
415		if (BSA_USB_CMD(BELKIN_SA_SET_DTR_REQUEST, 0) < 0)
416			dev_err(&port->dev, "DTR LOW error\n");
417		if (BSA_USB_CMD(BELKIN_SA_SET_RTS_REQUEST, 0) < 0)
418			dev_err(&port->dev, "RTS LOW error\n");
419	}
420
421	/* set the parity */
422	if ((cflag ^ old_cflag) & (PARENB | PARODD)) {
423		if (cflag & PARENB)
424			urb_value = (cflag & PARODD) ?  BELKIN_SA_PARITY_ODD
425						: BELKIN_SA_PARITY_EVEN;
426		else
427			urb_value = BELKIN_SA_PARITY_NONE;
428		if (BSA_USB_CMD(BELKIN_SA_SET_PARITY_REQUEST, urb_value) < 0)
429			dev_err(&port->dev, "Set parity error\n");
430	}
431
432	/* set the number of data bits */
433	if ((cflag & CSIZE) != (old_cflag & CSIZE)) {
434		switch (cflag & CSIZE) {
435		case CS5:
436			urb_value = BELKIN_SA_DATA_BITS(5);
437			break;
438		case CS6:
439			urb_value = BELKIN_SA_DATA_BITS(6);
440			break;
441		case CS7:
442			urb_value = BELKIN_SA_DATA_BITS(7);
443			break;
444		case CS8:
445			urb_value = BELKIN_SA_DATA_BITS(8);
446			break;
447		default: dbg("CSIZE was not CS5-CS8, using default of 8");
 
 
448			urb_value = BELKIN_SA_DATA_BITS(8);
449			break;
450		}
451		if (BSA_USB_CMD(BELKIN_SA_SET_DATA_BITS_REQUEST, urb_value) < 0)
452			dev_err(&port->dev, "Set data bits error\n");
453	}
454
455	/* set the number of stop bits */
456	if ((cflag & CSTOPB) != (old_cflag & CSTOPB)) {
457		urb_value = (cflag & CSTOPB) ? BELKIN_SA_STOP_BITS(2)
458						: BELKIN_SA_STOP_BITS(1);
459		if (BSA_USB_CMD(BELKIN_SA_SET_STOP_BITS_REQUEST,
460							urb_value) < 0)
461			dev_err(&port->dev, "Set stop bits error\n");
462	}
463
464	/* Set flow control */
465	if (((iflag ^ old_iflag) & (IXOFF | IXON)) ||
466		((cflag ^ old_cflag) & CRTSCTS)) {
467		urb_value = 0;
468		if ((iflag & IXOFF) || (iflag & IXON))
469			urb_value |= (BELKIN_SA_FLOW_OXON | BELKIN_SA_FLOW_IXON);
470		else
471			urb_value &= ~(BELKIN_SA_FLOW_OXON | BELKIN_SA_FLOW_IXON);
472
473		if (cflag & CRTSCTS)
474			urb_value |=  (BELKIN_SA_FLOW_OCTS | BELKIN_SA_FLOW_IRTS);
475		else
476			urb_value &= ~(BELKIN_SA_FLOW_OCTS | BELKIN_SA_FLOW_IRTS);
477
478		if (bad_flow_control)
479			urb_value &= ~(BELKIN_SA_FLOW_IRTS);
480
481		if (BSA_USB_CMD(BELKIN_SA_SET_FLOW_CTRL_REQUEST, urb_value) < 0)
482			dev_err(&port->dev, "Set flow control error\n");
483	}
484
485	/* save off the modified port settings */
486	spin_lock_irqsave(&priv->lock, flags);
487	priv->control_state = control_state;
488	spin_unlock_irqrestore(&priv->lock, flags);
489}
490
491static void belkin_sa_break_ctl(struct tty_struct *tty, int break_state)
492{
493	struct usb_serial_port *port = tty->driver_data;
494	struct usb_serial *serial = port->serial;
495
496	if (BSA_USB_CMD(BELKIN_SA_SET_BREAK_REQUEST, break_state ? 1 : 0) < 0)
497		dev_err(&port->dev, "Set break_ctl %d\n", break_state);
498}
499
500static int belkin_sa_tiocmget(struct tty_struct *tty)
501{
502	struct usb_serial_port *port = tty->driver_data;
503	struct belkin_sa_private *priv = usb_get_serial_port_data(port);
504	unsigned long control_state;
505	unsigned long flags;
506
507	dbg("%s", __func__);
508
509	spin_lock_irqsave(&priv->lock, flags);
510	control_state = priv->control_state;
511	spin_unlock_irqrestore(&priv->lock, flags);
512
513	return control_state;
514}
515
516static int belkin_sa_tiocmset(struct tty_struct *tty,
517			       unsigned int set, unsigned int clear)
518{
519	struct usb_serial_port *port = tty->driver_data;
520	struct usb_serial *serial = port->serial;
521	struct belkin_sa_private *priv = usb_get_serial_port_data(port);
522	unsigned long control_state;
523	unsigned long flags;
524	int retval;
525	int rts = 0;
526	int dtr = 0;
527
528	dbg("%s", __func__);
529
530	spin_lock_irqsave(&priv->lock, flags);
531	control_state = priv->control_state;
532
533	if (set & TIOCM_RTS) {
534		control_state |= TIOCM_RTS;
535		rts = 1;
536	}
537	if (set & TIOCM_DTR) {
538		control_state |= TIOCM_DTR;
539		dtr = 1;
540	}
541	if (clear & TIOCM_RTS) {
542		control_state &= ~TIOCM_RTS;
543		rts = 0;
544	}
545	if (clear & TIOCM_DTR) {
546		control_state &= ~TIOCM_DTR;
547		dtr = 0;
548	}
549
550	priv->control_state = control_state;
551	spin_unlock_irqrestore(&priv->lock, flags);
552
553	retval = BSA_USB_CMD(BELKIN_SA_SET_RTS_REQUEST, rts);
554	if (retval < 0) {
555		dev_err(&port->dev, "Set RTS error %d\n", retval);
556		goto exit;
557	}
558
559	retval = BSA_USB_CMD(BELKIN_SA_SET_DTR_REQUEST, dtr);
560	if (retval < 0) {
561		dev_err(&port->dev, "Set DTR error %d\n", retval);
562		goto exit;
563	}
564exit:
565	return retval;
566}
567
568
569static int __init belkin_sa_init(void)
570{
571	int retval;
572	retval = usb_serial_register(&belkin_device);
573	if (retval)
574		goto failed_usb_serial_register;
575	retval = usb_register(&belkin_driver);
576	if (retval)
577		goto failed_usb_register;
578	printk(KERN_INFO KBUILD_MODNAME ": " DRIVER_VERSION ":"
579	       DRIVER_DESC "\n");
580	return 0;
581failed_usb_register:
582	usb_serial_deregister(&belkin_device);
583failed_usb_serial_register:
584	return retval;
585}
586
587static void __exit belkin_sa_exit (void)
588{
589	usb_deregister(&belkin_driver);
590	usb_serial_deregister(&belkin_device);
591}
592
593
594module_init(belkin_sa_init);
595module_exit(belkin_sa_exit);
596
597MODULE_AUTHOR(DRIVER_AUTHOR);
598MODULE_DESCRIPTION(DRIVER_DESC);
599MODULE_VERSION(DRIVER_VERSION);
600MODULE_LICENSE("GPL");
601
602module_param(debug, bool, S_IRUGO | S_IWUSR);
603MODULE_PARM_DESC(debug, "Debug enabled or not");
v4.6
  1/*
  2 * Belkin USB Serial Adapter Driver
  3 *
  4 *  Copyright (C) 2000		William Greathouse (wgreathouse@smva.com)
  5 *  Copyright (C) 2000-2001	Greg Kroah-Hartman (greg@kroah.com)
  6 *  Copyright (C) 2010		Johan Hovold (jhovold@gmail.com)
  7 *
  8 *  This program is largely derived from work by the linux-usb group
  9 *  and associated source files.  Please see the usb/serial files for
 10 *  individual credits and copyrights.
 11 *
 12 *	This program is free software; you can redistribute it and/or modify
 13 *	it under the terms of the GNU General Public License as published by
 14 *	the Free Software Foundation; either version 2 of the License, or
 15 *	(at your option) any later version.
 16 *
 17 * See Documentation/usb/usb-serial.txt for more information on using this
 18 * driver
 19 *
 20 * TODO:
 21 * -- Add true modem control line query capability.  Currently we track the
 22 *    states reported by the interrupt and the states we request.
 
 
 
 23 * -- Add support for flush commands
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 24 */
 25
 26#include <linux/kernel.h>
 27#include <linux/errno.h>
 
 28#include <linux/slab.h>
 29#include <linux/tty.h>
 30#include <linux/tty_driver.h>
 31#include <linux/tty_flip.h>
 32#include <linux/module.h>
 33#include <linux/spinlock.h>
 34#include <linux/uaccess.h>
 35#include <linux/usb.h>
 36#include <linux/usb/serial.h>
 37#include "belkin_sa.h"
 38
 
 
 
 
 
 
 39#define DRIVER_AUTHOR "William Greathouse <wgreathouse@smva.com>"
 40#define DRIVER_DESC "USB Belkin Serial converter driver"
 41
 42/* function prototypes for a Belkin USB Serial Adapter F5U103 */
 43static int belkin_sa_port_probe(struct usb_serial_port *port);
 44static int belkin_sa_port_remove(struct usb_serial_port *port);
 45static int  belkin_sa_open(struct tty_struct *tty,
 46			struct usb_serial_port *port);
 47static void belkin_sa_close(struct usb_serial_port *port);
 48static void belkin_sa_read_int_callback(struct urb *urb);
 49static void belkin_sa_process_read_urb(struct urb *urb);
 50static void belkin_sa_set_termios(struct tty_struct *tty,
 51			struct usb_serial_port *port, struct ktermios * old);
 52static void belkin_sa_break_ctl(struct tty_struct *tty, int break_state);
 53static int  belkin_sa_tiocmget(struct tty_struct *tty);
 54static int  belkin_sa_tiocmset(struct tty_struct *tty,
 55					unsigned int set, unsigned int clear);
 56
 57
 58static const struct usb_device_id id_table[] = {
 59	{ USB_DEVICE(BELKIN_SA_VID, BELKIN_SA_PID) },
 60	{ USB_DEVICE(BELKIN_OLD_VID, BELKIN_OLD_PID) },
 61	{ USB_DEVICE(PERACOM_VID, PERACOM_PID) },
 62	{ USB_DEVICE(GOHUBS_VID, GOHUBS_PID) },
 63	{ USB_DEVICE(GOHUBS_VID, HANDYLINK_PID) },
 64	{ USB_DEVICE(BELKIN_DOCKSTATION_VID, BELKIN_DOCKSTATION_PID) },
 65	{ }	/* Terminating entry */
 66};
 67MODULE_DEVICE_TABLE(usb, id_table);
 
 
 
 
 
 
 
 
 68
 69/* All of the device info needed for the serial converters */
 70static struct usb_serial_driver belkin_device = {
 71	.driver = {
 72		.owner =	THIS_MODULE,
 73		.name =		"belkin",
 74	},
 75	.description =		"Belkin / Peracom / GoHubs USB Serial Adapter",
 76	.id_table =		id_table,
 
 77	.num_ports =		1,
 78	.open =			belkin_sa_open,
 79	.close =		belkin_sa_close,
 80	.read_int_callback =	belkin_sa_read_int_callback,
 81	.process_read_urb =	belkin_sa_process_read_urb,
 82	.set_termios =		belkin_sa_set_termios,
 83	.break_ctl =		belkin_sa_break_ctl,
 84	.tiocmget =		belkin_sa_tiocmget,
 85	.tiocmset =		belkin_sa_tiocmset,
 86	.port_probe =		belkin_sa_port_probe,
 87	.port_remove =		belkin_sa_port_remove,
 88};
 89
 90static struct usb_serial_driver * const serial_drivers[] = {
 91	&belkin_device, NULL
 92};
 93
 94struct belkin_sa_private {
 95	spinlock_t		lock;
 96	unsigned long		control_state;
 97	unsigned char		last_lsr;
 98	unsigned char		last_msr;
 99	int			bad_flow_control;
100};
101
102
103/*
104 * ***************************************************************************
105 * Belkin USB Serial Adapter F5U103 specific driver functions
106 * ***************************************************************************
107 */
108
109#define WDR_TIMEOUT 5000 /* default urb timeout */
110
111/* assumes that struct usb_serial *serial is available */
112#define BSA_USB_CMD(c, v) usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0), \
113					    (c), BELKIN_SA_SET_REQUEST_TYPE, \
114					    (v), 0, NULL, 0, WDR_TIMEOUT)
115
116static int belkin_sa_port_probe(struct usb_serial_port *port)
 
117{
118	struct usb_device *dev = port->serial->dev;
119	struct belkin_sa_private *priv;
120
 
121	priv = kmalloc(sizeof(struct belkin_sa_private), GFP_KERNEL);
122	if (!priv)
123		return -ENOMEM;
124
125	spin_lock_init(&priv->lock);
126	priv->control_state = 0;
127	priv->last_lsr = 0;
128	priv->last_msr = 0;
129	/* see comments at top of file */
130	priv->bad_flow_control =
131		(le16_to_cpu(dev->descriptor.bcdDevice) <= 0x0206) ? 1 : 0;
132	dev_info(&dev->dev, "bcdDevice: %04x, bfc: %d\n",
133					le16_to_cpu(dev->descriptor.bcdDevice),
134					priv->bad_flow_control);
135
136	usb_set_serial_port_data(port, priv);
 
137
138	return 0;
139}
140
141static int belkin_sa_port_remove(struct usb_serial_port *port)
142{
143	struct belkin_sa_private *priv;
144
145	priv = usb_get_serial_port_data(port);
146	kfree(priv);
147
148	return 0;
 
149}
150
151static int belkin_sa_open(struct tty_struct *tty,
152					struct usb_serial_port *port)
153{
154	int retval;
155
 
 
156	retval = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
157	if (retval) {
158		dev_err(&port->dev, "usb_submit_urb(read int) failed\n");
159		return retval;
160	}
161
162	retval = usb_serial_generic_open(tty, port);
163	if (retval)
164		usb_kill_urb(port->interrupt_in_urb);
165
166	return retval;
167}
168
169static void belkin_sa_close(struct usb_serial_port *port)
170{
 
 
171	usb_serial_generic_close(port);
172	usb_kill_urb(port->interrupt_in_urb);
173}
174
175static void belkin_sa_read_int_callback(struct urb *urb)
176{
177	struct usb_serial_port *port = urb->context;
178	struct belkin_sa_private *priv;
179	unsigned char *data = urb->transfer_buffer;
180	int retval;
181	int status = urb->status;
182	unsigned long flags;
183
184	switch (status) {
185	case 0:
186		/* success */
187		break;
188	case -ECONNRESET:
189	case -ENOENT:
190	case -ESHUTDOWN:
191		/* this urb is terminated, clean up */
192		dev_dbg(&port->dev, "%s - urb shutting down with status: %d\n",
193			__func__, status);
194		return;
195	default:
196		dev_dbg(&port->dev, "%s - nonzero urb status received: %d\n",
197			__func__, status);
198		goto exit;
199	}
200
201	usb_serial_debug_data(&port->dev, __func__, urb->actual_length, data);
 
202
203	/* Handle known interrupt data */
204	/* ignore data[0] and data[1] */
205
206	priv = usb_get_serial_port_data(port);
207	spin_lock_irqsave(&priv->lock, flags);
208	priv->last_msr = data[BELKIN_SA_MSR_INDEX];
209
210	/* Record Control Line states */
211	if (priv->last_msr & BELKIN_SA_MSR_DSR)
212		priv->control_state |= TIOCM_DSR;
213	else
214		priv->control_state &= ~TIOCM_DSR;
215
216	if (priv->last_msr & BELKIN_SA_MSR_CTS)
217		priv->control_state |= TIOCM_CTS;
218	else
219		priv->control_state &= ~TIOCM_CTS;
220
221	if (priv->last_msr & BELKIN_SA_MSR_RI)
222		priv->control_state |= TIOCM_RI;
223	else
224		priv->control_state &= ~TIOCM_RI;
225
226	if (priv->last_msr & BELKIN_SA_MSR_CD)
227		priv->control_state |= TIOCM_CD;
228	else
229		priv->control_state &= ~TIOCM_CD;
230
231	priv->last_lsr = data[BELKIN_SA_LSR_INDEX];
232	spin_unlock_irqrestore(&priv->lock, flags);
233exit:
234	retval = usb_submit_urb(urb, GFP_ATOMIC);
235	if (retval)
236		dev_err(&port->dev, "%s - usb_submit_urb failed with "
237			"result %d\n", __func__, retval);
238}
239
240static void belkin_sa_process_read_urb(struct urb *urb)
241{
242	struct usb_serial_port *port = urb->context;
243	struct belkin_sa_private *priv = usb_get_serial_port_data(port);
 
244	unsigned char *data = urb->transfer_buffer;
245	unsigned long flags;
246	unsigned char status;
247	char tty_flag;
248
249	/* Update line status */
250	tty_flag = TTY_NORMAL;
251
252	spin_lock_irqsave(&priv->lock, flags);
253	status = priv->last_lsr;
254	priv->last_lsr &= ~BELKIN_SA_LSR_ERR;
255	spin_unlock_irqrestore(&priv->lock, flags);
256
257	if (!urb->actual_length)
258		return;
259
 
 
 
 
260	if (status & BELKIN_SA_LSR_ERR) {
261		/* Break takes precedence over parity, which takes precedence
262		 * over framing errors. */
263		if (status & BELKIN_SA_LSR_BI)
264			tty_flag = TTY_BREAK;
265		else if (status & BELKIN_SA_LSR_PE)
266			tty_flag = TTY_PARITY;
267		else if (status & BELKIN_SA_LSR_FE)
268			tty_flag = TTY_FRAME;
269		dev_dbg(&port->dev, "tty_flag = %d\n", tty_flag);
270
271		/* Overrun is special, not associated with a char. */
272		if (status & BELKIN_SA_LSR_OE)
273			tty_insert_flip_char(&port->port, 0, TTY_OVERRUN);
274	}
275
276	tty_insert_flip_string_fixed_flag(&port->port, data, tty_flag,
277							urb->actual_length);
278	tty_flip_buffer_push(&port->port);
 
279}
280
281static void belkin_sa_set_termios(struct tty_struct *tty,
282		struct usb_serial_port *port, struct ktermios *old_termios)
283{
284	struct usb_serial *serial = port->serial;
285	struct belkin_sa_private *priv = usb_get_serial_port_data(port);
286	unsigned int iflag;
287	unsigned int cflag;
288	unsigned int old_iflag = 0;
289	unsigned int old_cflag = 0;
290	__u16 urb_value = 0; /* Will hold the new flags */
291	unsigned long flags;
292	unsigned long control_state;
293	int bad_flow_control;
294	speed_t baud;
295	struct ktermios *termios = &tty->termios;
296
297	iflag = termios->c_iflag;
298	cflag = termios->c_cflag;
299
300	termios->c_cflag &= ~CMSPAR;
301
302	/* get a local copy of the current port settings */
303	spin_lock_irqsave(&priv->lock, flags);
304	control_state = priv->control_state;
305	bad_flow_control = priv->bad_flow_control;
306	spin_unlock_irqrestore(&priv->lock, flags);
307
308	old_iflag = old_termios->c_iflag;
309	old_cflag = old_termios->c_cflag;
310
311	/* Set the baud rate */
312	if ((cflag & CBAUD) != (old_cflag & CBAUD)) {
313		/* reassert DTR and (maybe) RTS on transition from B0 */
314		if ((old_cflag & CBAUD) == B0) {
315			control_state |= (TIOCM_DTR|TIOCM_RTS);
316			if (BSA_USB_CMD(BELKIN_SA_SET_DTR_REQUEST, 1) < 0)
317				dev_err(&port->dev, "Set DTR error\n");
318			/* don't set RTS if using hardware flow control */
319			if (!(old_cflag & CRTSCTS))
320				if (BSA_USB_CMD(BELKIN_SA_SET_RTS_REQUEST
321								, 1) < 0)
322					dev_err(&port->dev, "Set RTS error\n");
323		}
324	}
325
326	baud = tty_get_baud_rate(tty);
327	if (baud) {
328		urb_value = BELKIN_SA_BAUD(baud);
329		/* Clip to maximum speed */
330		if (urb_value == 0)
331			urb_value = 1;
332		/* Turn it back into a resulting real baud rate */
333		baud = BELKIN_SA_BAUD(urb_value);
334
335		/* Report the actual baud rate back to the caller */
336		tty_encode_baud_rate(tty, baud, baud);
337		if (BSA_USB_CMD(BELKIN_SA_SET_BAUDRATE_REQUEST, urb_value) < 0)
338			dev_err(&port->dev, "Set baudrate error\n");
339	} else {
340		/* Disable flow control */
341		if (BSA_USB_CMD(BELKIN_SA_SET_FLOW_CTRL_REQUEST,
342						BELKIN_SA_FLOW_NONE) < 0)
343			dev_err(&port->dev, "Disable flowcontrol error\n");
344		/* Drop RTS and DTR */
345		control_state &= ~(TIOCM_DTR | TIOCM_RTS);
346		if (BSA_USB_CMD(BELKIN_SA_SET_DTR_REQUEST, 0) < 0)
347			dev_err(&port->dev, "DTR LOW error\n");
348		if (BSA_USB_CMD(BELKIN_SA_SET_RTS_REQUEST, 0) < 0)
349			dev_err(&port->dev, "RTS LOW error\n");
350	}
351
352	/* set the parity */
353	if ((cflag ^ old_cflag) & (PARENB | PARODD)) {
354		if (cflag & PARENB)
355			urb_value = (cflag & PARODD) ?  BELKIN_SA_PARITY_ODD
356						: BELKIN_SA_PARITY_EVEN;
357		else
358			urb_value = BELKIN_SA_PARITY_NONE;
359		if (BSA_USB_CMD(BELKIN_SA_SET_PARITY_REQUEST, urb_value) < 0)
360			dev_err(&port->dev, "Set parity error\n");
361	}
362
363	/* set the number of data bits */
364	if ((cflag & CSIZE) != (old_cflag & CSIZE)) {
365		switch (cflag & CSIZE) {
366		case CS5:
367			urb_value = BELKIN_SA_DATA_BITS(5);
368			break;
369		case CS6:
370			urb_value = BELKIN_SA_DATA_BITS(6);
371			break;
372		case CS7:
373			urb_value = BELKIN_SA_DATA_BITS(7);
374			break;
375		case CS8:
376			urb_value = BELKIN_SA_DATA_BITS(8);
377			break;
378		default:
379			dev_dbg(&port->dev,
380				"CSIZE was not CS5-CS8, using default of 8\n");
381			urb_value = BELKIN_SA_DATA_BITS(8);
382			break;
383		}
384		if (BSA_USB_CMD(BELKIN_SA_SET_DATA_BITS_REQUEST, urb_value) < 0)
385			dev_err(&port->dev, "Set data bits error\n");
386	}
387
388	/* set the number of stop bits */
389	if ((cflag & CSTOPB) != (old_cflag & CSTOPB)) {
390		urb_value = (cflag & CSTOPB) ? BELKIN_SA_STOP_BITS(2)
391						: BELKIN_SA_STOP_BITS(1);
392		if (BSA_USB_CMD(BELKIN_SA_SET_STOP_BITS_REQUEST,
393							urb_value) < 0)
394			dev_err(&port->dev, "Set stop bits error\n");
395	}
396
397	/* Set flow control */
398	if (((iflag ^ old_iflag) & (IXOFF | IXON)) ||
399		((cflag ^ old_cflag) & CRTSCTS)) {
400		urb_value = 0;
401		if ((iflag & IXOFF) || (iflag & IXON))
402			urb_value |= (BELKIN_SA_FLOW_OXON | BELKIN_SA_FLOW_IXON);
403		else
404			urb_value &= ~(BELKIN_SA_FLOW_OXON | BELKIN_SA_FLOW_IXON);
405
406		if (cflag & CRTSCTS)
407			urb_value |=  (BELKIN_SA_FLOW_OCTS | BELKIN_SA_FLOW_IRTS);
408		else
409			urb_value &= ~(BELKIN_SA_FLOW_OCTS | BELKIN_SA_FLOW_IRTS);
410
411		if (bad_flow_control)
412			urb_value &= ~(BELKIN_SA_FLOW_IRTS);
413
414		if (BSA_USB_CMD(BELKIN_SA_SET_FLOW_CTRL_REQUEST, urb_value) < 0)
415			dev_err(&port->dev, "Set flow control error\n");
416	}
417
418	/* save off the modified port settings */
419	spin_lock_irqsave(&priv->lock, flags);
420	priv->control_state = control_state;
421	spin_unlock_irqrestore(&priv->lock, flags);
422}
423
424static void belkin_sa_break_ctl(struct tty_struct *tty, int break_state)
425{
426	struct usb_serial_port *port = tty->driver_data;
427	struct usb_serial *serial = port->serial;
428
429	if (BSA_USB_CMD(BELKIN_SA_SET_BREAK_REQUEST, break_state ? 1 : 0) < 0)
430		dev_err(&port->dev, "Set break_ctl %d\n", break_state);
431}
432
433static int belkin_sa_tiocmget(struct tty_struct *tty)
434{
435	struct usb_serial_port *port = tty->driver_data;
436	struct belkin_sa_private *priv = usb_get_serial_port_data(port);
437	unsigned long control_state;
438	unsigned long flags;
439
 
 
440	spin_lock_irqsave(&priv->lock, flags);
441	control_state = priv->control_state;
442	spin_unlock_irqrestore(&priv->lock, flags);
443
444	return control_state;
445}
446
447static int belkin_sa_tiocmset(struct tty_struct *tty,
448			       unsigned int set, unsigned int clear)
449{
450	struct usb_serial_port *port = tty->driver_data;
451	struct usb_serial *serial = port->serial;
452	struct belkin_sa_private *priv = usb_get_serial_port_data(port);
453	unsigned long control_state;
454	unsigned long flags;
455	int retval;
456	int rts = 0;
457	int dtr = 0;
458
 
 
459	spin_lock_irqsave(&priv->lock, flags);
460	control_state = priv->control_state;
461
462	if (set & TIOCM_RTS) {
463		control_state |= TIOCM_RTS;
464		rts = 1;
465	}
466	if (set & TIOCM_DTR) {
467		control_state |= TIOCM_DTR;
468		dtr = 1;
469	}
470	if (clear & TIOCM_RTS) {
471		control_state &= ~TIOCM_RTS;
472		rts = 0;
473	}
474	if (clear & TIOCM_DTR) {
475		control_state &= ~TIOCM_DTR;
476		dtr = 0;
477	}
478
479	priv->control_state = control_state;
480	spin_unlock_irqrestore(&priv->lock, flags);
481
482	retval = BSA_USB_CMD(BELKIN_SA_SET_RTS_REQUEST, rts);
483	if (retval < 0) {
484		dev_err(&port->dev, "Set RTS error %d\n", retval);
485		goto exit;
486	}
487
488	retval = BSA_USB_CMD(BELKIN_SA_SET_DTR_REQUEST, dtr);
489	if (retval < 0) {
490		dev_err(&port->dev, "Set DTR error %d\n", retval);
491		goto exit;
492	}
493exit:
494	return retval;
495}
496
497module_usb_serial_driver(serial_drivers, id_table);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
498
499MODULE_AUTHOR(DRIVER_AUTHOR);
500MODULE_DESCRIPTION(DRIVER_DESC);
 
501MODULE_LICENSE("GPL");