xref: /linux/drivers/usb/serial/ftdi_sio.c (revision b454cc6636d254fbf6049b73e9560aee76fb04a3)
1 /*
2  * USB FTDI SIO driver
3  *
4  *	Copyright (C) 1999 - 2001
5  *	    Greg Kroah-Hartman (greg@kroah.com)
6  *          Bill Ryder (bryder@sgi.com)
7  *	Copyright (C) 2002
8  *	    Kuba Ober (kuba@mareimbrium.org)
9  *
10  *	This program is free software; you can redistribute it and/or modify
11  *	it under the terms of the GNU General Public License as published by
12  *	the Free Software Foundation; either version 2 of the License, or
13  *	(at your option) any later version.
14  *
15  * See Documentation/usb/usb-serial.txt for more information on using this driver
16  *
17  * See http://ftdi-usb-sio.sourceforge.net for upto date testing info
18  *	and extra documentation
19  *
20  * (21/Jul/2004) Ian Abbott
21  *      Incorporated Steven Turner's code to add support for the FT2232C chip.
22  *      The prelimilary port to the 2.6 kernel was by Rus V. Brushkoff.  I have
23  *      fixed a couple of things.
24  *
25  * (27/May/2004) Ian Abbott
26  *      Improved throttling code, mostly stolen from the WhiteHEAT driver.
27  *
28  * (26/Mar/2004) Jan Capek
29  *      Added PID's for ICD-U20/ICD-U40 - incircuit PIC debuggers from CCS Inc.
30  *
31  * (09/Feb/2004) Ian Abbott
32  *      Changed full name of USB-UIRT device to avoid "/" character.
33  *      Added FTDI's alternate PID (0x6006) for FT232/245 devices.
34  *      Added PID for "ELV USB Module UO100" from Stefan Frings.
35  *
36  * (21/Oct/2003) Ian Abbott
37  *      Renamed some VID/PID macros for Matrix Orbital and Perle Systems
38  *      devices.  Removed Matrix Orbital and Perle Systems devices from the
39  *      8U232AM device table, but left them in the FT232BM table, as they are
40  *      known to use only FT232BM.
41  *
42  * (17/Oct/2003) Scott Allen
43  *      Added vid/pid for Perle Systems UltraPort USB serial converters
44  *
45  * (21/Sep/2003) Ian Abbott
46  *      Added VID/PID for Omnidirectional Control Technology US101 USB to
47  *      RS-232 adapter (also rebadged as Dick Smith Electronics XH6381).
48  *      VID/PID supplied by Donald Gordon.
49  *
50  * (19/Aug/2003) Ian Abbott
51  *      Freed urb's transfer buffer in write bulk callback.
52  *      Omitted some paranoid checks in write bulk callback that don't matter.
53  *      Scheduled work in write bulk callback regardless of port's open count.
54  *
55  * (05/Aug/2003) Ian Abbott
56  *      Added VID/PID for ID TECH IDT1221U USB to RS-232 adapter.
57  *      VID/PID provided by Steve Briggs.
58  *
59  * (23/Jul/2003) Ian Abbott
60  *      Added PIDs for CrystalFontz 547, 633, 631, 635, 640 and 640 from
61  *      Wayne Wylupski.
62  *
63  * (10/Jul/2003) David Glance
64  *      Added PID for DSS-20 SyncStation cradle for Sony-Ericsson P800.
65  *
66  * (27/Jun/2003) Ian Abbott
67  *	Reworked the urb handling logic.  We have no more pool, but dynamically
68  *	allocate the urb and the transfer buffer on the fly.  In testing this
69  *	does not incure any measurable overhead.  This also relies on the fact
70  *	that we have proper reference counting logic for urbs.  I nicked this
71  *	from Greg KH's Visor driver.
72  *
73  * (23/Jun/2003) Ian Abbott
74  *      Reduced flip buffer pushes and corrected a data length test in
75  *      ftdi_read_bulk_callback.
76  *      Defererence pointers after any paranoid checks, not before.
77  *
78  * (21/Jun/2003) Erik Nygren
79  *      Added support for Home Electronics Tira-1 IR transceiver using FT232BM chip.
80  *      See <http://www.home-electro.com/tira1.htm>.  Only operates properly
81  *      at 100000 and RTS-CTS, so set custom divisor mode on startup.
82  *      Also force the Tira-1 and USB-UIRT to only use their custom baud rates.
83  *
84  * (18/Jun/2003) Ian Abbott
85  *      Added Device ID of the USB relais from Rudolf Gugler (backported from
86  *      Philipp G�hring's patch for 2.5.x kernel).
87  *      Moved read transfer buffer reallocation into startup function.
88  *      Free existing write urb and transfer buffer in startup function.
89  *      Only use urbs in write urb pool that were successfully allocated.
90  *      Moved some constant macros out of functions.
91  *      Minor whitespace and comment changes.
92  *
93  * (12/Jun/2003) David Norwood
94  *      Added support for USB-UIRT IR transceiver using 8U232AM chip.
95  *      See <http://home.earthlink.net/~jrhees/USBUIRT/index.htm>.  Only
96  *      operates properly at 312500, so set custom divisor mode on startup.
97  *
98  * (12/Jun/2003) Ian Abbott
99  *      Added Sealevel SeaLINK+ 210x, 220x, 240x, 280x vid/pids from Tuan Hoang
100  *      - I've eliminated some that don't seem to exist!
101  *      Added Home Electronics Tira-1 IR transceiver pid from Chris Horn
102  *      Some whitespace/coding-style cleanups
103  *
104  * (11/Jun/2003) Ian Abbott
105  *      Fixed unsafe spinlock usage in ftdi_write
106  *
107  * (24/Feb/2003) Richard Shooter
108  *      Increase read buffer size to improve read speeds at higher baud rates
109  *      (specifically tested with up to 1Mb/sec at 1.5M baud)
110  *
111  * (23/Feb/2003) John Wilkins
112  *      Added Xon/xoff flow control (activating support in the ftdi device)
113  *      Added vid/pid for Videonetworks/Homechoice (UK ISP)
114  *
115  * (23/Feb/2003) Bill Ryder
116  *      Added matrix orb device vid/pids from Wayne Wylupski
117  *
118  * (19/Feb/2003) Ian Abbott
119  *      For TIOCSSERIAL, set alt_speed to 0 when ASYNC_SPD_MASK value has
120  *      changed to something other than ASYNC_SPD_HI, ASYNC_SPD_VHI,
121  *      ASYNC_SPD_SHI or ASYNC_SPD_WARP.  Also, unless ASYNC_SPD_CUST is in
122  *      force, don't bother changing baud rate when custom_divisor has changed.
123  *
124  * (18/Feb/2003) Ian Abbott
125  *      Fixed TIOCMGET handling to include state of DTR and RTS, the state
126  *      of which are now saved by set_dtr() and set_rts().
127  *      Fixed improper storage class for buf in set_dtr() and set_rts().
128  *      Added FT232BM chip type and support for its extra baud rates (compared
129  *      to FT8U232AM).
130  *      Took account of special case divisor values for highest baud rates of
131  *      FT8U232AM and FT232BM.
132  *      For TIOCSSERIAL, forced alt_speed to 0 when ASYNC_SPD_CUST kludge used,
133  *      as previous alt_speed setting is now stale.
134  *      Moved startup code common between the startup routines for the
135  *      different chip types into a common subroutine.
136  *
137  * (17/Feb/2003) Bill Ryder
138  *      Added write urb buffer pool on a per device basis
139  *      Added more checking for open file on callbacks (fixed OOPS)
140  *      Added CrystalFontz 632 and 634 PIDs
141  *         (thanx to CrystalFontz for the sample devices - they flushed out
142  *           some driver bugs)
143  *      Minor debugging message changes
144  *      Added throttle, unthrottle and chars_in_buffer functions
145  *      Fixed FTDI_SIO (the original device) bug
146  *      Fixed some shutdown handling
147  *
148  *
149  *
150  *
151  * (07/Jun/2002) Kuba Ober
152  *	Changed FTDI_SIO_BASE_BAUD_TO_DIVISOR macro into ftdi_baud_to_divisor
153  *	function. It was getting too complex.
154  *	Fix the divisor calculation logic which was setting divisor of 0.125
155  *	instead of 0.5 for fractional parts of divisor equal to 5/8, 6/8, 7/8.
156  *	Also make it bump up the divisor to next integer in case of 7/8 - it's
157  *	a better approximation.
158  *
159  * (25/Jul/2002) Bill Ryder inserted Dmitri's TIOCMIWAIT patch
160  *      Not tested by me but it doesn't break anything I use.
161  *
162  * (04/Jan/2002) Kuba Ober
163  *	Implemented 38400 baudrate kludge, where it can be substituted with other
164  *	  values. That's the only way to set custom baudrates.
165  *	Implemented TIOCSSERIAL, TIOCGSERIAL ioctl's so that setserial is happy.
166  *	FIXME: both baudrate things should eventually go to usbserial.c as other
167  *	  devices may need that functionality too. Actually, it can probably be
168  *	  merged in serial.c somehow - too many drivers repeat this code over
169  *	  and over.
170  *	Fixed baudrate forgetfulness - open() used to reset baudrate to 9600 every time.
171  *	Divisors for baudrates are calculated by a macro.
172  *	Small code cleanups. Ugly whitespace changes for Plato's sake only ;-].
173  *
174  * (04/Nov/2001) Bill Ryder
175  *	Fixed bug in read_bulk_callback where incorrect urb buffer was used.
176  *	Cleaned up write offset calculation
177  *	Added write_room since default values can be incorrect for sio
178  *	Changed write_bulk_callback to use same queue_task as other drivers
179  *        (the previous version caused panics)
180  *	Removed port iteration code since the device only has one I/O port and it
181  *	  was wrong anyway.
182  *
183  * (31/May/2001) gkh
184  *	Switched from using spinlock to a semaphore, which fixes lots of problems.
185  *
186  * (23/May/2001)   Bill Ryder
187  *	Added runtime debug patch (thanx Tyson D Sawyer).
188  *	Cleaned up comments for 8U232
189  *	Added parity, framing and overrun error handling
190  *	Added receive break handling.
191  *
192  * (04/08/2001) gb
193  *	Identify version on module load.
194  *
195  * (18/March/2001) Bill Ryder
196  *	(Not released)
197  *	Added send break handling. (requires kernel patch too)
198  *	Fixed 8U232AM hardware RTS/CTS etc status reporting.
199  *	Added flipbuf fix copied from generic device
200  *
201  * (12/3/2000) Bill Ryder
202  *	Added support for 8U232AM device.
203  *	Moved PID and VIDs into header file only.
204  *	Turned on low-latency for the tty (device will do high baudrates)
205  *	Added shutdown routine to close files when device removed.
206  *	More debug and error message cleanups.
207  *
208  * (11/13/2000) Bill Ryder
209  *	Added spinlock protected open code and close code.
210  *	Multiple opens work (sort of - see webpage mentioned above).
211  *	Cleaned up comments. Removed multiple PID/VID definitions.
212  *	Factorised cts/dtr code
213  *	Made use of __FUNCTION__ in dbg's
214  *
215  * (11/01/2000) Adam J. Richter
216  *	usb_device_id table support
217  *
218  * (10/05/2000) gkh
219  *	Fixed bug with urb->dev not being set properly, now that the usb
220  *	core needs it.
221  *
222  * (09/11/2000) gkh
223  *	Removed DEBUG #ifdefs with call to usb_serial_debug_data
224  *
225  * (07/19/2000) gkh
226  *	Added module_init and module_exit functions to handle the fact that this
227  *	driver is a loadable module now.
228  *
229  * (04/04/2000) Bill Ryder
230  *	Fixed bugs in TCGET/TCSET ioctls (by removing them - they are
231  *        handled elsewhere in the tty io driver chain).
232  *
233  * (03/30/2000) Bill Ryder
234  *	Implemented lots of ioctls
235  *	Fixed a race condition in write
236  *	Changed some dbg's to errs
237  *
238  * (03/26/2000) gkh
239  *	Split driver up into device specific pieces.
240  *
241  */
242 
243 /* Bill Ryder - bryder@sgi.com - wrote the FTDI_SIO implementation */
244 /* Thanx to FTDI for so kindly providing details of the protocol required */
245 /*   to talk to the device */
246 /* Thanx to gkh and the rest of the usb dev group for all code I have assimilated :-) */
247 
248 #include <linux/kernel.h>
249 #include <linux/errno.h>
250 #include <linux/init.h>
251 #include <linux/slab.h>
252 #include <linux/tty.h>
253 #include <linux/tty_driver.h>
254 #include <linux/tty_flip.h>
255 #include <linux/module.h>
256 #include <linux/spinlock.h>
257 #include <asm/uaccess.h>
258 #include <linux/usb.h>
259 #include <linux/serial.h>
260 #include <linux/usb/serial.h>
261 #include "ftdi_sio.h"
262 
263 /*
264  * Version Information
265  */
266 #define DRIVER_VERSION "v1.4.3"
267 #define DRIVER_AUTHOR "Greg Kroah-Hartman <greg@kroah.com>, Bill Ryder <bryder@sgi.com>, Kuba Ober <kuba@mareimbrium.org>"
268 #define DRIVER_DESC "USB FTDI Serial Converters Driver"
269 
270 static int debug;
271 static __u16 vendor = FTDI_VID;
272 static __u16 product;
273 
274 /* struct ftdi_sio_quirk is used by devices requiring special attention. */
275 struct ftdi_sio_quirk {
276 	void (*setup)(struct usb_serial *); /* Special settings during startup. */
277 };
278 
279 static void  ftdi_USB_UIRT_setup	(struct usb_serial *serial);
280 static void  ftdi_HE_TIRA1_setup	(struct usb_serial *serial);
281 
282 static struct ftdi_sio_quirk ftdi_USB_UIRT_quirk = {
283 	.setup = ftdi_USB_UIRT_setup,
284 };
285 
286 static struct ftdi_sio_quirk ftdi_HE_TIRA1_quirk = {
287 	.setup = ftdi_HE_TIRA1_setup,
288 };
289 
290 /*
291  * The 8U232AM has the same API as the sio except for:
292  * - it can support MUCH higher baudrates; up to:
293  *   o 921600 for RS232 and 2000000 for RS422/485 at 48MHz
294  *   o 230400 at 12MHz
295  *   so .. 8U232AM's baudrate setting codes are different
296  * - it has a two byte status code.
297  * - it returns characters every 16ms (the FTDI does it every 40ms)
298  *
299  * the bcdDevice value is used to differentiate FT232BM and FT245BM from
300  * the earlier FT8U232AM and FT8U232BM.  For now, include all known VID/PID
301  * combinations in both tables.
302  * FIXME: perhaps bcdDevice can also identify 12MHz FT8U232AM devices,
303  * but I don't know if those ever went into mass production. [Ian Abbott]
304  */
305 
306 
307 
308 static struct usb_device_id id_table_combined [] = {
309 	{ USB_DEVICE(FTDI_VID, FTDI_AMC232_PID) },
310 	{ USB_DEVICE(FTDI_VID, FTDI_CANUSB_PID) },
311 	{ USB_DEVICE(FTDI_VID, FTDI_ACTZWAVE_PID) },
312 	{ USB_DEVICE(FTDI_VID, FTDI_IRTRANS_PID) },
313 	{ USB_DEVICE(FTDI_VID, FTDI_IPLUS_PID) },
314 	{ USB_DEVICE(FTDI_VID, FTDI_DMX4ALL) },
315 	{ USB_DEVICE(FTDI_VID, FTDI_SIO_PID) },
316 	{ USB_DEVICE(FTDI_VID, FTDI_8U232AM_PID) },
317 	{ USB_DEVICE(FTDI_VID, FTDI_8U232AM_ALT_PID) },
318 	{ USB_DEVICE(FTDI_VID, FTDI_8U2232C_PID) },
319 	{ USB_DEVICE(FTDI_VID, FTDI_MICRO_CHAMELEON_PID) },
320 	{ USB_DEVICE(FTDI_VID, FTDI_RELAIS_PID) },
321 	{ USB_DEVICE(INTERBIOMETRICS_VID, INTERBIOMETRICS_IOBOARD_PID) },
322 	{ USB_DEVICE(INTERBIOMETRICS_VID, INTERBIOMETRICS_MINI_IOBOARD_PID) },
323 	{ USB_DEVICE(FTDI_VID, FTDI_XF_632_PID) },
324 	{ USB_DEVICE(FTDI_VID, FTDI_XF_634_PID) },
325 	{ USB_DEVICE(FTDI_VID, FTDI_XF_547_PID) },
326 	{ USB_DEVICE(FTDI_VID, FTDI_XF_633_PID) },
327 	{ USB_DEVICE(FTDI_VID, FTDI_XF_631_PID) },
328 	{ USB_DEVICE(FTDI_VID, FTDI_XF_635_PID) },
329 	{ USB_DEVICE(FTDI_VID, FTDI_XF_640_PID) },
330 	{ USB_DEVICE(FTDI_VID, FTDI_XF_642_PID) },
331 	{ USB_DEVICE(FTDI_VID, FTDI_DSS20_PID) },
332 	{ USB_DEVICE(FTDI_NF_RIC_VID, FTDI_NF_RIC_PID) },
333 	{ USB_DEVICE(FTDI_VID, FTDI_VNHCPCUSB_D_PID) },
334 	{ USB_DEVICE(FTDI_VID, FTDI_MTXORB_0_PID) },
335 	{ USB_DEVICE(FTDI_VID, FTDI_MTXORB_1_PID) },
336 	{ USB_DEVICE(FTDI_VID, FTDI_MTXORB_2_PID) },
337 	{ USB_DEVICE(FTDI_VID, FTDI_MTXORB_3_PID) },
338 	{ USB_DEVICE(FTDI_VID, FTDI_MTXORB_4_PID) },
339 	{ USB_DEVICE(FTDI_VID, FTDI_MTXORB_5_PID) },
340 	{ USB_DEVICE(FTDI_VID, FTDI_MTXORB_6_PID) },
341 	{ USB_DEVICE(FTDI_VID, FTDI_PERLE_ULTRAPORT_PID) },
342 	{ USB_DEVICE(FTDI_VID, FTDI_PIEGROUP_PID) },
343 	{ USB_DEVICE(FTDI_VID, FTDI_TNC_X_PID) },
344 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2101_PID) },
345 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2102_PID) },
346 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2103_PID) },
347 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2104_PID) },
348 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2106_PID) },
349 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2201_1_PID) },
350 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2201_2_PID) },
351 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2202_1_PID) },
352 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2202_2_PID) },
353 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2203_1_PID) },
354 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2203_2_PID) },
355 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2401_1_PID) },
356 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2401_2_PID) },
357 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2401_3_PID) },
358 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2401_4_PID) },
359 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2402_1_PID) },
360 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2402_2_PID) },
361 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2402_3_PID) },
362 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2402_4_PID) },
363 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2403_1_PID) },
364 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2403_2_PID) },
365 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2403_3_PID) },
366 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2403_4_PID) },
367 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2801_1_PID) },
368 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2801_2_PID) },
369 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2801_3_PID) },
370 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2801_4_PID) },
371 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2801_5_PID) },
372 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2801_6_PID) },
373 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2801_7_PID) },
374 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2801_8_PID) },
375 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2802_1_PID) },
376 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2802_2_PID) },
377 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2802_3_PID) },
378 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2802_4_PID) },
379 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2802_5_PID) },
380 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2802_6_PID) },
381 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2802_7_PID) },
382 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2802_8_PID) },
383 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2803_1_PID) },
384 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2803_2_PID) },
385 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2803_3_PID) },
386 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2803_4_PID) },
387 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2803_5_PID) },
388 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2803_6_PID) },
389 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2803_7_PID) },
390 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2803_8_PID) },
391 	{ USB_DEVICE(IDTECH_VID, IDTECH_IDT1221U_PID) },
392 	{ USB_DEVICE(OCT_VID, OCT_US101_PID) },
393 	{ USB_DEVICE(FTDI_VID, FTDI_HE_TIRA1_PID),
394 		.driver_info = (kernel_ulong_t)&ftdi_HE_TIRA1_quirk },
395 	{ USB_DEVICE(FTDI_VID, FTDI_USB_UIRT_PID),
396 		.driver_info = (kernel_ulong_t)&ftdi_USB_UIRT_quirk },
397 	{ USB_DEVICE(FTDI_VID, PROTEGO_SPECIAL_1) },
398 	{ USB_DEVICE(FTDI_VID, PROTEGO_R2X0) },
399 	{ USB_DEVICE(FTDI_VID, PROTEGO_SPECIAL_3) },
400 	{ USB_DEVICE(FTDI_VID, PROTEGO_SPECIAL_4) },
401 	{ USB_DEVICE(FTDI_VID, FTDI_GUDEADS_E808_PID) },
402 	{ USB_DEVICE(FTDI_VID, FTDI_GUDEADS_E809_PID) },
403 	{ USB_DEVICE(FTDI_VID, FTDI_GUDEADS_E80A_PID) },
404 	{ USB_DEVICE(FTDI_VID, FTDI_GUDEADS_E80B_PID) },
405 	{ USB_DEVICE(FTDI_VID, FTDI_GUDEADS_E80C_PID) },
406 	{ USB_DEVICE(FTDI_VID, FTDI_GUDEADS_E80D_PID) },
407 	{ USB_DEVICE(FTDI_VID, FTDI_GUDEADS_E80E_PID) },
408 	{ USB_DEVICE(FTDI_VID, FTDI_GUDEADS_E80F_PID) },
409 	{ USB_DEVICE(FTDI_VID, FTDI_GUDEADS_E888_PID) },
410 	{ USB_DEVICE(FTDI_VID, FTDI_GUDEADS_E889_PID) },
411 	{ USB_DEVICE(FTDI_VID, FTDI_GUDEADS_E88A_PID) },
412 	{ USB_DEVICE(FTDI_VID, FTDI_GUDEADS_E88B_PID) },
413 	{ USB_DEVICE(FTDI_VID, FTDI_GUDEADS_E88C_PID) },
414 	{ USB_DEVICE(FTDI_VID, FTDI_GUDEADS_E88D_PID) },
415 	{ USB_DEVICE(FTDI_VID, FTDI_GUDEADS_E88E_PID) },
416 	{ USB_DEVICE(FTDI_VID, FTDI_GUDEADS_E88F_PID) },
417 	{ USB_DEVICE(FTDI_VID, FTDI_ELV_UO100_PID) },
418 	{ USB_DEVICE(FTDI_VID, FTDI_ELV_UM100_PID) },
419 	{ USB_DEVICE(FTDI_VID, FTDI_ELV_UR100_PID) },
420 	{ USB_DEVICE(FTDI_VID, FTDI_ELV_ALC8500_PID) },
421 	{ USB_DEVICE(FTDI_VID, FTDI_PYRAMID_PID) },
422 	{ USB_DEVICE(FTDI_VID, FTDI_ELV_FHZ1000PC_PID) },
423 	/*
424 	 * These will probably use user-space drivers.  Uncomment them if
425 	 * you need them or use the user-specified vendor/product module
426 	 * parameters (see ftdi_sio.h for the numbers).  Make a fuss if
427 	 * you think the driver should recognize any of them by default.
428 	 */
429 	/* { USB_DEVICE(FTDI_VID, FTDI_ELV_CLI7000_PID) }, */
430 	/* { USB_DEVICE(FTDI_VID, FTDI_ELV_PPS7330_PID) }, */
431 	/* { USB_DEVICE(FTDI_VID, FTDI_ELV_TFM100_PID) }, */
432 	/* { USB_DEVICE(FTDI_VID, FTDI_ELV_UDF77_PID) }, */
433 	/* { USB_DEVICE(FTDI_VID, FTDI_ELV_UIO88_PID) }, */
434 	/* { USB_DEVICE(FTDI_VID, FTDI_ELV_UAD8_PID) }, */
435 	/* { USB_DEVICE(FTDI_VID, FTDI_ELV_UDA7_PID) }, */
436 	/* { USB_DEVICE(FTDI_VID, FTDI_ELV_USI2_PID) }, */
437 	/* { USB_DEVICE(FTDI_VID, FTDI_ELV_T1100_PID) }, */
438 	/* { USB_DEVICE(FTDI_VID, FTDI_ELV_PCD200_PID) }, */
439 	/* { USB_DEVICE(FTDI_VID, FTDI_ELV_ULA200_PID) }, */
440 	/* { USB_DEVICE(FTDI_VID, FTDI_ELV_CSI8_PID) }, */
441 	/* { USB_DEVICE(FTDI_VID, FTDI_ELV_EM1000DL_PID) }, */
442 	/* { USB_DEVICE(FTDI_VID, FTDI_ELV_PCK100_PID) }, */
443 	/* { USB_DEVICE(FTDI_VID, FTDI_ELV_RFP500_PID) }, */
444 	/* { USB_DEVICE(FTDI_VID, FTDI_ELV_FS20SIG_PID) }, */
445 	/* { USB_DEVICE(FTDI_VID, FTDI_ELV_WS300PC_PID) }, */
446 	/* { USB_DEVICE(FTDI_VID, FTDI_ELV_FHZ1300PC_PID) }, */
447 	/* { USB_DEVICE(FTDI_VID, FTDI_ELV_WS500_PID) }, */
448 	{ USB_DEVICE(FTDI_VID, LINX_SDMUSBQSS_PID) },
449 	{ USB_DEVICE(FTDI_VID, LINX_MASTERDEVEL2_PID) },
450 	{ USB_DEVICE(FTDI_VID, LINX_FUTURE_0_PID) },
451 	{ USB_DEVICE(FTDI_VID, LINX_FUTURE_1_PID) },
452 	{ USB_DEVICE(FTDI_VID, LINX_FUTURE_2_PID) },
453 	{ USB_DEVICE(FTDI_VID, FTDI_CCSICDU20_0_PID) },
454 	{ USB_DEVICE(FTDI_VID, FTDI_CCSICDU40_1_PID) },
455 	{ USB_DEVICE(FTDI_VID, FTDI_CCSMACHX_2_PID) },
456 	{ USB_DEVICE(FTDI_VID, INSIDE_ACCESSO) },
457 	{ USB_DEVICE(INTREPID_VID, INTREPID_VALUECAN_PID) },
458 	{ USB_DEVICE(INTREPID_VID, INTREPID_NEOVI_PID) },
459 	{ USB_DEVICE(FALCOM_VID, FALCOM_TWIST_PID) },
460 	{ USB_DEVICE(FALCOM_VID, FALCOM_SAMBA_PID) },
461 	{ USB_DEVICE(FTDI_VID, FTDI_SUUNTO_SPORTS_PID) },
462 	{ USB_DEVICE(FTDI_VID, FTDI_RM_CANVIEW_PID) },
463 	{ USB_DEVICE(BANDB_VID, BANDB_USOTL4_PID) },
464 	{ USB_DEVICE(BANDB_VID, BANDB_USTL4_PID) },
465 	{ USB_DEVICE(BANDB_VID, BANDB_USO9ML2_PID) },
466 	{ USB_DEVICE(FTDI_VID, EVER_ECO_PRO_CDS) },
467 	{ USB_DEVICE(FTDI_VID, FTDI_4N_GALAXY_DE_1_PID) },
468 	{ USB_DEVICE(FTDI_VID, FTDI_4N_GALAXY_DE_2_PID) },
469 	{ USB_DEVICE(FTDI_VID, XSENS_CONVERTER_0_PID) },
470 	{ USB_DEVICE(FTDI_VID, XSENS_CONVERTER_1_PID) },
471 	{ USB_DEVICE(FTDI_VID, XSENS_CONVERTER_2_PID) },
472 	{ USB_DEVICE(FTDI_VID, XSENS_CONVERTER_3_PID) },
473 	{ USB_DEVICE(FTDI_VID, XSENS_CONVERTER_4_PID) },
474 	{ USB_DEVICE(FTDI_VID, XSENS_CONVERTER_5_PID) },
475 	{ USB_DEVICE(FTDI_VID, XSENS_CONVERTER_6_PID) },
476 	{ USB_DEVICE(FTDI_VID, XSENS_CONVERTER_7_PID) },
477 	{ USB_DEVICE(MOBILITY_VID, MOBILITY_USB_SERIAL_PID) },
478 	{ USB_DEVICE(FTDI_VID, FTDI_ACTIVE_ROBOTS_PID) },
479 	{ USB_DEVICE(FTDI_VID, FTDI_MHAM_KW_PID) },
480 	{ USB_DEVICE(FTDI_VID, FTDI_MHAM_YS_PID) },
481 	{ USB_DEVICE(FTDI_VID, FTDI_MHAM_Y6_PID) },
482 	{ USB_DEVICE(FTDI_VID, FTDI_MHAM_Y8_PID) },
483 	{ USB_DEVICE(FTDI_VID, FTDI_MHAM_IC_PID) },
484 	{ USB_DEVICE(FTDI_VID, FTDI_MHAM_DB9_PID) },
485 	{ USB_DEVICE(FTDI_VID, FTDI_MHAM_RS232_PID) },
486 	{ USB_DEVICE(FTDI_VID, FTDI_MHAM_Y9_PID) },
487 	{ USB_DEVICE(FTDI_VID, FTDI_TERATRONIK_VCP_PID) },
488 	{ USB_DEVICE(FTDI_VID, FTDI_TERATRONIK_D2XX_PID) },
489 	{ USB_DEVICE(EVOLUTION_VID, EVOLUTION_ER1_PID) },
490 	{ USB_DEVICE(FTDI_VID, FTDI_ARTEMIS_PID) },
491 	{ USB_DEVICE(FTDI_VID, FTDI_ATIK_ATK16_PID) },
492 	{ USB_DEVICE(FTDI_VID, FTDI_ATIK_ATK16C_PID) },
493 	{ USB_DEVICE(FTDI_VID, FTDI_ATIK_ATK16HR_PID) },
494 	{ USB_DEVICE(FTDI_VID, FTDI_ATIK_ATK16HRC_PID) },
495 	{ USB_DEVICE(KOBIL_VID, KOBIL_CONV_B1_PID) },
496 	{ USB_DEVICE(KOBIL_VID, KOBIL_CONV_KAAN_PID) },
497 	{ USB_DEVICE(POSIFLEX_VID, POSIFLEX_PP7000_PID) },
498 	{ USB_DEVICE(FTDI_VID, FTDI_TTUSB_PID) },
499 	{ USB_DEVICE(FTDI_VID, FTDI_ECLO_COM_1WIRE_PID) },
500 	{ USB_DEVICE(FTDI_VID, FTDI_WESTREX_MODEL_777_PID) },
501 	{ USB_DEVICE(FTDI_VID, FTDI_WESTREX_MODEL_8900F_PID) },
502 	{ USB_DEVICE(FTDI_VID, FTDI_PCDJ_DAC2_PID) },
503 	{ USB_DEVICE(FTDI_VID, FTDI_RRCIRKITS_LOCOBUFFER_PID) },
504 	{ USB_DEVICE(FTDI_VID, FTDI_ASK_RDR400_PID) },
505 	{ USB_DEVICE(ICOM_ID1_VID, ICOM_ID1_PID) },
506 	{ USB_DEVICE(PAPOUCH_VID, PAPOUCH_TMU_PID) },
507 	{ USB_DEVICE(FTDI_VID, FTDI_ACG_HFDUAL_PID) },
508 	{ USB_DEVICE(FTDI_VID, FTDI_YEI_SERVOCENTER31_PID) },
509 	{ USB_DEVICE(FTDI_VID, FTDI_THORLABS_PID) },
510 	{ USB_DEVICE(TESTO_VID, TESTO_USB_INTERFACE_PID) },
511 	{ USB_DEVICE(FTDI_VID, FTDI_GAMMA_SCOUT_PID) },
512 	{ USB_DEVICE(FTDI_VID, FTDI_TACTRIX_OPENPORT_13M_PID) },
513 	{ USB_DEVICE(FTDI_VID, FTDI_TACTRIX_OPENPORT_13S_PID) },
514 	{ USB_DEVICE(FTDI_VID, FTDI_TACTRIX_OPENPORT_13U_PID) },
515 	{ USB_DEVICE(ELEKTOR_VID, ELEKTOR_FT323R_PID) },
516 	{ },					/* Optional parameter entry */
517 	{ }					/* Terminating entry */
518 };
519 
520 MODULE_DEVICE_TABLE (usb, id_table_combined);
521 
522 static struct usb_driver ftdi_driver = {
523 	.name =		"ftdi_sio",
524 	.probe =	usb_serial_probe,
525 	.disconnect =	usb_serial_disconnect,
526 	.id_table =	id_table_combined,
527 	.no_dynamic_id =	1,
528 };
529 
530 static const char *ftdi_chip_name[] = {
531 	[SIO] = "SIO",	/* the serial part of FT8U100AX */
532 	[FT8U232AM] = "FT8U232AM",
533 	[FT232BM] = "FT232BM",
534 	[FT2232C] = "FT2232C",
535 };
536 
537 
538 /* Constants for read urb and write urb */
539 #define BUFSZ 512
540 #define PKTSZ 64
541 
542 /* rx_flags */
543 #define THROTTLED		0x01
544 #define ACTUALLY_THROTTLED	0x02
545 
546 struct ftdi_private {
547 	ftdi_chip_type_t chip_type;
548 				/* type of the device, either SIO or FT8U232AM */
549 	int baud_base;		/* baud base clock for divisor setting */
550 	int custom_divisor;	/* custom_divisor kludge, this is for baud_base (different from what goes to the chip!) */
551 	__u16 last_set_data_urb_value ;
552 				/* the last data state set - needed for doing a break */
553         int write_offset;       /* This is the offset in the usb data block to write the serial data -
554 				 * it is different between devices
555 				 */
556 	int flags;		/* some ASYNC_xxxx flags are supported */
557 	unsigned long last_dtr_rts;	/* saved modem control outputs */
558         wait_queue_head_t delta_msr_wait; /* Used for TIOCMIWAIT */
559 	char prev_status, diff_status;        /* Used for TIOCMIWAIT */
560 	__u8 rx_flags;		/* receive state flags (throttling) */
561 	spinlock_t rx_lock;	/* spinlock for receive state */
562 	struct delayed_work rx_work;
563 	struct usb_serial_port *port;
564 	int rx_processed;
565 	unsigned long rx_bytes;
566 
567 	__u16 interface;	/* FT2232C port interface (0 for FT232/245) */
568 
569 	int force_baud;		/* if non-zero, force the baud rate to this value */
570 	int force_rtscts;	/* if non-zero, force RTS-CTS to always be enabled */
571 
572 	spinlock_t tx_lock;	/* spinlock for transmit state */
573 	unsigned long tx_bytes;
574 	unsigned long tx_outstanding_bytes;
575 	unsigned long tx_outstanding_urbs;
576 };
577 
578 /* Used for TIOCMIWAIT */
579 #define FTDI_STATUS_B0_MASK	(FTDI_RS0_CTS | FTDI_RS0_DSR | FTDI_RS0_RI | FTDI_RS0_RLSD)
580 #define FTDI_STATUS_B1_MASK	(FTDI_RS_BI)
581 /* End TIOCMIWAIT */
582 
583 #define FTDI_IMPL_ASYNC_FLAGS = ( ASYNC_SPD_HI | ASYNC_SPD_VHI \
584  ASYNC_SPD_CUST | ASYNC_SPD_SHI | ASYNC_SPD_WARP )
585 
586 /* function prototypes for a FTDI serial converter */
587 static int  ftdi_sio_probe	(struct usb_serial *serial, const struct usb_device_id *id);
588 static int  ftdi_sio_attach		(struct usb_serial *serial);
589 static void ftdi_shutdown		(struct usb_serial *serial);
590 static int  ftdi_open			(struct usb_serial_port *port, struct file *filp);
591 static void ftdi_close			(struct usb_serial_port *port, struct file *filp);
592 static int  ftdi_write			(struct usb_serial_port *port, const unsigned char *buf, int count);
593 static int  ftdi_write_room		(struct usb_serial_port *port);
594 static int  ftdi_chars_in_buffer	(struct usb_serial_port *port);
595 static void ftdi_write_bulk_callback	(struct urb *urb);
596 static void ftdi_read_bulk_callback	(struct urb *urb);
597 static void ftdi_process_read		(struct work_struct *work);
598 static void ftdi_set_termios		(struct usb_serial_port *port, struct ktermios * old);
599 static int  ftdi_tiocmget               (struct usb_serial_port *port, struct file *file);
600 static int  ftdi_tiocmset		(struct usb_serial_port *port, struct file * file, unsigned int set, unsigned int clear);
601 static int  ftdi_ioctl			(struct usb_serial_port *port, struct file * file, unsigned int cmd, unsigned long arg);
602 static void ftdi_break_ctl		(struct usb_serial_port *port, int break_state );
603 static void ftdi_throttle		(struct usb_serial_port *port);
604 static void ftdi_unthrottle		(struct usb_serial_port *port);
605 
606 static unsigned short int ftdi_232am_baud_base_to_divisor (int baud, int base);
607 static unsigned short int ftdi_232am_baud_to_divisor (int baud);
608 static __u32 ftdi_232bm_baud_base_to_divisor (int baud, int base);
609 static __u32 ftdi_232bm_baud_to_divisor (int baud);
610 
611 static struct usb_serial_driver ftdi_sio_device = {
612 	.driver = {
613 		.owner =	THIS_MODULE,
614 		.name =		"ftdi_sio",
615 	},
616 	.description =		"FTDI USB Serial Device",
617 	.usb_driver = 		&ftdi_driver ,
618 	.id_table =		id_table_combined,
619 	.num_interrupt_in =	0,
620 	.num_bulk_in =		1,
621 	.num_bulk_out =		1,
622 	.num_ports =		1,
623 	.probe =		ftdi_sio_probe,
624 	.open =			ftdi_open,
625 	.close =		ftdi_close,
626 	.throttle =		ftdi_throttle,
627 	.unthrottle =		ftdi_unthrottle,
628 	.write =		ftdi_write,
629 	.write_room =		ftdi_write_room,
630 	.chars_in_buffer =	ftdi_chars_in_buffer,
631 	.read_bulk_callback =	ftdi_read_bulk_callback,
632 	.write_bulk_callback =	ftdi_write_bulk_callback,
633 	.tiocmget =             ftdi_tiocmget,
634 	.tiocmset =             ftdi_tiocmset,
635 	.ioctl =		ftdi_ioctl,
636 	.set_termios =		ftdi_set_termios,
637 	.break_ctl =		ftdi_break_ctl,
638 	.attach =		ftdi_sio_attach,
639 	.shutdown =		ftdi_shutdown,
640 };
641 
642 
643 #define WDR_TIMEOUT 5000 /* default urb timeout */
644 #define WDR_SHORT_TIMEOUT 1000	/* shorter urb timeout */
645 
646 /* High and low are for DTR, RTS etc etc */
647 #define HIGH 1
648 #define LOW 0
649 
650 /* number of outstanding urbs to prevent userspace DoS from happening */
651 #define URB_UPPER_LIMIT	42
652 
653 /*
654  * ***************************************************************************
655  * Utlity functions
656  * ***************************************************************************
657  */
658 
659 static unsigned short int ftdi_232am_baud_base_to_divisor(int baud, int base)
660 {
661 	unsigned short int divisor;
662 	int divisor3 = base / 2 / baud; // divisor shifted 3 bits to the left
663 	if ((divisor3 & 0x7) == 7) divisor3 ++; // round x.7/8 up to x+1
664 	divisor = divisor3 >> 3;
665 	divisor3 &= 0x7;
666 	if (divisor3 == 1) divisor |= 0xc000; else // 0.125
667 	if (divisor3 >= 4) divisor |= 0x4000; else // 0.5
668 	if (divisor3 != 0) divisor |= 0x8000;      // 0.25
669 	if (divisor == 1) divisor = 0;	/* special case for maximum baud rate */
670 	return divisor;
671 }
672 
673 static unsigned short int ftdi_232am_baud_to_divisor(int baud)
674 {
675 	 return(ftdi_232am_baud_base_to_divisor(baud, 48000000));
676 }
677 
678 static __u32 ftdi_232bm_baud_base_to_divisor(int baud, int base)
679 {
680 	static const unsigned char divfrac[8] = { 0, 3, 2, 4, 1, 5, 6, 7 };
681 	__u32 divisor;
682 	int divisor3 = base / 2 / baud; // divisor shifted 3 bits to the left
683 	divisor = divisor3 >> 3;
684 	divisor |= (__u32)divfrac[divisor3 & 0x7] << 14;
685 	/* Deal with special cases for highest baud rates. */
686 	if (divisor == 1) divisor = 0; else	// 1.0
687 	if (divisor == 0x4001) divisor = 1;	// 1.5
688 	return divisor;
689 }
690 
691 static __u32 ftdi_232bm_baud_to_divisor(int baud)
692 {
693 	 return(ftdi_232bm_baud_base_to_divisor(baud, 48000000));
694 }
695 
696 #define set_mctrl(port, set)		update_mctrl((port), (set), 0)
697 #define clear_mctrl(port, clear)	update_mctrl((port), 0, (clear))
698 
699 static int update_mctrl(struct usb_serial_port *port, unsigned int set, unsigned int clear)
700 {
701 	struct ftdi_private *priv = usb_get_serial_port_data(port);
702 	char *buf;
703 	unsigned urb_value;
704 	int rv;
705 
706 	if (((set | clear) & (TIOCM_DTR | TIOCM_RTS)) == 0) {
707 		dbg("%s - DTR|RTS not being set|cleared", __FUNCTION__);
708 		return 0;	/* no change */
709 	}
710 
711 	buf = kmalloc(1, GFP_NOIO);
712 	if (!buf) {
713 		return -ENOMEM;
714 	}
715 
716 	clear &= ~set;	/* 'set' takes precedence over 'clear' */
717 	urb_value = 0;
718 	if (clear & TIOCM_DTR)
719 		urb_value |= FTDI_SIO_SET_DTR_LOW;
720 	if (clear & TIOCM_RTS)
721 		urb_value |= FTDI_SIO_SET_RTS_LOW;
722 	if (set & TIOCM_DTR)
723 		urb_value |= FTDI_SIO_SET_DTR_HIGH;
724 	if (set & TIOCM_RTS)
725 		urb_value |= FTDI_SIO_SET_RTS_HIGH;
726 	rv = usb_control_msg(port->serial->dev,
727 			       usb_sndctrlpipe(port->serial->dev, 0),
728 			       FTDI_SIO_SET_MODEM_CTRL_REQUEST,
729 			       FTDI_SIO_SET_MODEM_CTRL_REQUEST_TYPE,
730 			       urb_value, priv->interface,
731 			       buf, 0, WDR_TIMEOUT);
732 
733 	kfree(buf);
734 	if (rv < 0) {
735 		err("%s Error from MODEM_CTRL urb: DTR %s, RTS %s",
736 				__FUNCTION__,
737 				(set & TIOCM_DTR) ? "HIGH" :
738 				(clear & TIOCM_DTR) ? "LOW" : "unchanged",
739 				(set & TIOCM_RTS) ? "HIGH" :
740 				(clear & TIOCM_RTS) ? "LOW" : "unchanged");
741 	} else {
742 		dbg("%s - DTR %s, RTS %s", __FUNCTION__,
743 				(set & TIOCM_DTR) ? "HIGH" :
744 				(clear & TIOCM_DTR) ? "LOW" : "unchanged",
745 				(set & TIOCM_RTS) ? "HIGH" :
746 				(clear & TIOCM_RTS) ? "LOW" : "unchanged");
747 		priv->last_dtr_rts = (priv->last_dtr_rts & ~clear) | set;
748 	}
749 	return rv;
750 }
751 
752 
753 static __u32 get_ftdi_divisor(struct usb_serial_port * port);
754 
755 
756 static int change_speed(struct usb_serial_port *port)
757 {
758 	struct ftdi_private *priv = usb_get_serial_port_data(port);
759 	char *buf;
760         __u16 urb_value;
761 	__u16 urb_index;
762 	__u32 urb_index_value;
763 	int rv;
764 
765 	buf = kmalloc(1, GFP_NOIO);
766 	if (!buf)
767 		return -ENOMEM;
768 
769 	urb_index_value = get_ftdi_divisor(port);
770 	urb_value = (__u16)urb_index_value;
771 	urb_index = (__u16)(urb_index_value >> 16);
772 	if (priv->interface) {	/* FT2232C */
773 		urb_index = (__u16)((urb_index << 8) | priv->interface);
774 	}
775 
776 	rv = usb_control_msg(port->serial->dev,
777 			    usb_sndctrlpipe(port->serial->dev, 0),
778 			    FTDI_SIO_SET_BAUDRATE_REQUEST,
779 			    FTDI_SIO_SET_BAUDRATE_REQUEST_TYPE,
780 			    urb_value, urb_index,
781 			    buf, 0, WDR_SHORT_TIMEOUT);
782 
783 	kfree(buf);
784 	return rv;
785 }
786 
787 
788 static __u32 get_ftdi_divisor(struct usb_serial_port * port)
789 { /* get_ftdi_divisor */
790 	struct ftdi_private *priv = usb_get_serial_port_data(port);
791 	__u32 div_value = 0;
792 	int div_okay = 1;
793 	int baud;
794 
795 	/*
796 	 * The logic involved in setting the baudrate can be cleanly split in 3 steps.
797 	 * Obtaining the actual baud rate is a little tricky since unix traditionally
798 	 * somehow ignored the possibility to set non-standard baud rates.
799 	 * 1. Standard baud rates are set in tty->termios->c_cflag
800 	 * 2. If these are not enough, you can set any speed using alt_speed as follows:
801 	 *    - set tty->termios->c_cflag speed to B38400
802 	 *    - set your real speed in tty->alt_speed; it gets ignored when
803 	 *      alt_speed==0, (or)
804 	 *    - call TIOCSSERIAL ioctl with (struct serial_struct) set as follows:
805 	 *      flags & ASYNC_SPD_MASK == ASYNC_SPD_[HI, VHI, SHI, WARP], this just
806 	 *      sets alt_speed to (HI: 57600, VHI: 115200, SHI: 230400, WARP: 460800)
807 	 * ** Steps 1, 2 are done courtesy of tty_get_baud_rate
808 	 * 3. You can also set baud rate by setting custom divisor as follows
809 	 *    - set tty->termios->c_cflag speed to B38400
810 	 *    - call TIOCSSERIAL ioctl with (struct serial_struct) set as follows:
811 	 *      o flags & ASYNC_SPD_MASK == ASYNC_SPD_CUST
812 	 *      o custom_divisor set to baud_base / your_new_baudrate
813 	 * ** Step 3 is done courtesy of code borrowed from serial.c - I should really
814 	 *    spend some time and separate+move this common code to serial.c, it is
815 	 *    replicated in nearly every serial driver you see.
816 	 */
817 
818 	/* 1. Get the baud rate from the tty settings, this observes alt_speed hack */
819 
820 	baud = tty_get_baud_rate(port->tty);
821 	dbg("%s - tty_get_baud_rate reports speed %d", __FUNCTION__, baud);
822 
823 	/* 2. Observe async-compatible custom_divisor hack, update baudrate if needed */
824 
825 	if (baud == 38400 &&
826 	    ((priv->flags & ASYNC_SPD_MASK) == ASYNC_SPD_CUST) &&
827 	     (priv->custom_divisor)) {
828 		baud = priv->baud_base / priv->custom_divisor;
829 		dbg("%s - custom divisor %d sets baud rate to %d", __FUNCTION__, priv->custom_divisor, baud);
830 	}
831 
832 	/* 3. Convert baudrate to device-specific divisor */
833 
834 	if (!baud) baud = 9600;
835 	switch(priv->chip_type) {
836 	case SIO: /* SIO chip */
837 		switch(baud) {
838 		case 300: div_value = ftdi_sio_b300; break;
839 		case 600: div_value = ftdi_sio_b600; break;
840 		case 1200: div_value = ftdi_sio_b1200; break;
841 		case 2400: div_value = ftdi_sio_b2400; break;
842 		case 4800: div_value = ftdi_sio_b4800; break;
843 		case 9600: div_value = ftdi_sio_b9600; break;
844 		case 19200: div_value = ftdi_sio_b19200; break;
845 		case 38400: div_value = ftdi_sio_b38400; break;
846 		case 57600: div_value = ftdi_sio_b57600;  break;
847 		case 115200: div_value = ftdi_sio_b115200; break;
848 		} /* baud */
849 		if (div_value == 0) {
850 			dbg("%s - Baudrate (%d) requested is not supported", __FUNCTION__,  baud);
851 			div_value = ftdi_sio_b9600;
852 			div_okay = 0;
853 		}
854 		break;
855 	case FT8U232AM: /* 8U232AM chip */
856 		if (baud <= 3000000) {
857 			div_value = ftdi_232am_baud_to_divisor(baud);
858 		} else {
859 	                dbg("%s - Baud rate too high!", __FUNCTION__);
860 			div_value = ftdi_232am_baud_to_divisor(9600);
861 			div_okay = 0;
862 		}
863 		break;
864 	case FT232BM: /* FT232BM chip */
865 	case FT2232C: /* FT2232C chip */
866 		if (baud <= 3000000) {
867 			div_value = ftdi_232bm_baud_to_divisor(baud);
868 		} else {
869 	                dbg("%s - Baud rate too high!", __FUNCTION__);
870 			div_value = ftdi_232bm_baud_to_divisor(9600);
871 			div_okay = 0;
872 		}
873 		break;
874 	} /* priv->chip_type */
875 
876 	if (div_okay) {
877 		dbg("%s - Baud rate set to %d (divisor 0x%lX) on chip %s",
878 			__FUNCTION__, baud, (unsigned long)div_value,
879 			ftdi_chip_name[priv->chip_type]);
880 	}
881 
882 	return(div_value);
883 }
884 
885 
886 static int get_serial_info(struct usb_serial_port * port, struct serial_struct __user * retinfo)
887 {
888 	struct ftdi_private *priv = usb_get_serial_port_data(port);
889 	struct serial_struct tmp;
890 
891 	if (!retinfo)
892 		return -EFAULT;
893 	memset(&tmp, 0, sizeof(tmp));
894 	tmp.flags = priv->flags;
895 	tmp.baud_base = priv->baud_base;
896 	tmp.custom_divisor = priv->custom_divisor;
897 	if (copy_to_user(retinfo, &tmp, sizeof(*retinfo)))
898 		return -EFAULT;
899 	return 0;
900 } /* get_serial_info */
901 
902 
903 static int set_serial_info(struct usb_serial_port * port, struct serial_struct __user * newinfo)
904 { /* set_serial_info */
905 	struct ftdi_private *priv = usb_get_serial_port_data(port);
906 	struct serial_struct new_serial;
907 	struct ftdi_private old_priv;
908 
909 	if (copy_from_user(&new_serial, newinfo, sizeof(new_serial)))
910 		return -EFAULT;
911 	old_priv = * priv;
912 
913 	/* Do error checking and permission checking */
914 
915 	if (!capable(CAP_SYS_ADMIN)) {
916 		if (((new_serial.flags & ~ASYNC_USR_MASK) !=
917 		     (priv->flags & ~ASYNC_USR_MASK)))
918 			return -EPERM;
919 		priv->flags = ((priv->flags & ~ASYNC_USR_MASK) |
920 			       (new_serial.flags & ASYNC_USR_MASK));
921 		priv->custom_divisor = new_serial.custom_divisor;
922 		goto check_and_exit;
923 	}
924 
925 	if ((new_serial.baud_base != priv->baud_base) &&
926 	    (new_serial.baud_base < 9600))
927 		return -EINVAL;
928 
929 	/* Make the changes - these are privileged changes! */
930 
931 	priv->flags = ((priv->flags & ~ASYNC_FLAGS) |
932 	               (new_serial.flags & ASYNC_FLAGS));
933 	priv->custom_divisor = new_serial.custom_divisor;
934 
935 	port->tty->low_latency = (priv->flags & ASYNC_LOW_LATENCY) ? 1 : 0;
936 
937 check_and_exit:
938 	if ((old_priv.flags & ASYNC_SPD_MASK) !=
939 	     (priv->flags & ASYNC_SPD_MASK)) {
940 		if ((priv->flags & ASYNC_SPD_MASK) == ASYNC_SPD_HI)
941 			port->tty->alt_speed = 57600;
942 		else if ((priv->flags & ASYNC_SPD_MASK) == ASYNC_SPD_VHI)
943 			port->tty->alt_speed = 115200;
944 		else if ((priv->flags & ASYNC_SPD_MASK) == ASYNC_SPD_SHI)
945 			port->tty->alt_speed = 230400;
946 		else if ((priv->flags & ASYNC_SPD_MASK) == ASYNC_SPD_WARP)
947 			port->tty->alt_speed = 460800;
948 		else
949 			port->tty->alt_speed = 0;
950 	}
951 	if (((old_priv.flags & ASYNC_SPD_MASK) !=
952 	     (priv->flags & ASYNC_SPD_MASK)) ||
953 	    (((priv->flags & ASYNC_SPD_MASK) == ASYNC_SPD_CUST) &&
954 	     (old_priv.custom_divisor != priv->custom_divisor))) {
955 		change_speed(port);
956 	}
957 
958 	return (0);
959 
960 } /* set_serial_info */
961 
962 
963 /* Determine type of FTDI chip based on USB config and descriptor. */
964 static void ftdi_determine_type(struct usb_serial_port *port)
965 {
966 	struct ftdi_private *priv = usb_get_serial_port_data(port);
967 	struct usb_serial *serial = port->serial;
968 	struct usb_device *udev = serial->dev;
969 	unsigned version;
970 	unsigned interfaces;
971 
972 	/* Assume it is not the original SIO device for now. */
973 	priv->baud_base = 48000000 / 2;
974 	priv->write_offset = 0;
975 
976 	version = le16_to_cpu(udev->descriptor.bcdDevice);
977 	interfaces = udev->actconfig->desc.bNumInterfaces;
978 	dbg("%s: bcdDevice = 0x%x, bNumInterfaces = %u", __FUNCTION__,
979 			version, interfaces);
980 	if (interfaces > 1) {
981 		int inter;
982 
983 		/* Multiple interfaces.  Assume FT2232C. */
984 		priv->chip_type = FT2232C;
985 		/* Determine interface code. */
986 		inter = serial->interface->altsetting->desc.bInterfaceNumber;
987 		if (inter == 0) {
988 			priv->interface = PIT_SIOA;
989 		} else {
990 			priv->interface = PIT_SIOB;
991 		}
992 		/* BM-type devices have a bug where bcdDevice gets set
993 		 * to 0x200 when iSerialNumber is 0.  */
994 		if (version < 0x500) {
995 			dbg("%s: something fishy - bcdDevice too low for multi-interface device",
996 					__FUNCTION__);
997 		}
998 	} else if (version < 0x200) {
999 		/* Old device.  Assume its the original SIO. */
1000 		priv->chip_type = SIO;
1001 		priv->baud_base = 12000000 / 16;
1002 		priv->write_offset = 1;
1003 	} else if (version < 0x400) {
1004 		/* Assume its an FT8U232AM (or FT8U245AM) */
1005 		/* (It might be a BM because of the iSerialNumber bug,
1006 		 * but it will still work as an AM device.) */
1007 		priv->chip_type = FT8U232AM;
1008 	} else {
1009 		/* Assume its an FT232BM (or FT245BM) */
1010 		priv->chip_type = FT232BM;
1011 	}
1012 	info("Detected %s", ftdi_chip_name[priv->chip_type]);
1013 }
1014 
1015 
1016 /*
1017  * ***************************************************************************
1018  * Sysfs Attribute
1019  * ***************************************************************************
1020  */
1021 
1022 static ssize_t show_latency_timer(struct device *dev, struct device_attribute *attr, char *buf)
1023 {
1024 	struct usb_serial_port *port = to_usb_serial_port(dev);
1025 	struct ftdi_private *priv = usb_get_serial_port_data(port);
1026 	struct usb_device *udev;
1027 	unsigned short latency = 0;
1028 	int rv = 0;
1029 
1030 	udev = to_usb_device(dev);
1031 
1032 	dbg("%s",__FUNCTION__);
1033 
1034 	rv = usb_control_msg(udev,
1035 			     usb_rcvctrlpipe(udev, 0),
1036 			     FTDI_SIO_GET_LATENCY_TIMER_REQUEST,
1037 			     FTDI_SIO_GET_LATENCY_TIMER_REQUEST_TYPE,
1038 			     0, priv->interface,
1039 			     (char*) &latency, 1, WDR_TIMEOUT);
1040 
1041 	if (rv < 0) {
1042 		dev_err(dev, "Unable to read latency timer: %i", rv);
1043 		return -EIO;
1044 	}
1045 	return sprintf(buf, "%i\n", latency);
1046 }
1047 
1048 /* Write a new value of the latency timer, in units of milliseconds. */
1049 static ssize_t store_latency_timer(struct device *dev, struct device_attribute *attr, const char *valbuf,
1050 				   size_t count)
1051 {
1052 	struct usb_serial_port *port = to_usb_serial_port(dev);
1053 	struct ftdi_private *priv = usb_get_serial_port_data(port);
1054 	struct usb_device *udev;
1055 	char buf[1];
1056 	int v = simple_strtoul(valbuf, NULL, 10);
1057 	int rv = 0;
1058 
1059 	udev = to_usb_device(dev);
1060 
1061 	dbg("%s: setting latency timer = %i", __FUNCTION__, v);
1062 
1063 	rv = usb_control_msg(udev,
1064 			     usb_sndctrlpipe(udev, 0),
1065 			     FTDI_SIO_SET_LATENCY_TIMER_REQUEST,
1066 			     FTDI_SIO_SET_LATENCY_TIMER_REQUEST_TYPE,
1067 			     v, priv->interface,
1068 			     buf, 0, WDR_TIMEOUT);
1069 
1070 	if (rv < 0) {
1071 		dev_err(dev, "Unable to write latency timer: %i", rv);
1072 		return -EIO;
1073 	}
1074 
1075 	return count;
1076 }
1077 
1078 /* Write an event character directly to the FTDI register.  The ASCII
1079    value is in the low 8 bits, with the enable bit in the 9th bit. */
1080 static ssize_t store_event_char(struct device *dev, struct device_attribute *attr, const char *valbuf,
1081 				size_t count)
1082 {
1083 	struct usb_serial_port *port = to_usb_serial_port(dev);
1084 	struct ftdi_private *priv = usb_get_serial_port_data(port);
1085 	struct usb_device *udev;
1086 	char buf[1];
1087 	int v = simple_strtoul(valbuf, NULL, 10);
1088 	int rv = 0;
1089 
1090 	udev = to_usb_device(dev);
1091 
1092 	dbg("%s: setting event char = %i", __FUNCTION__, v);
1093 
1094 	rv = usb_control_msg(udev,
1095 			     usb_sndctrlpipe(udev, 0),
1096 			     FTDI_SIO_SET_EVENT_CHAR_REQUEST,
1097 			     FTDI_SIO_SET_EVENT_CHAR_REQUEST_TYPE,
1098 			     v, priv->interface,
1099 			     buf, 0, WDR_TIMEOUT);
1100 
1101 	if (rv < 0) {
1102 		dbg("Unable to write event character: %i", rv);
1103 		return -EIO;
1104 	}
1105 
1106 	return count;
1107 }
1108 
1109 static DEVICE_ATTR(latency_timer, S_IWUSR | S_IRUGO, show_latency_timer, store_latency_timer);
1110 static DEVICE_ATTR(event_char, S_IWUSR, NULL, store_event_char);
1111 
1112 static int create_sysfs_attrs(struct usb_serial *serial)
1113 {
1114 	struct ftdi_private *priv;
1115 	struct usb_device *udev;
1116 	int retval = 0;
1117 
1118 	dbg("%s",__FUNCTION__);
1119 
1120 	priv = usb_get_serial_port_data(serial->port[0]);
1121 	udev = serial->dev;
1122 
1123 	/* XXX I've no idea if the original SIO supports the event_char
1124 	 * sysfs parameter, so I'm playing it safe.  */
1125 	if (priv->chip_type != SIO) {
1126 		dbg("sysfs attributes for %s", ftdi_chip_name[priv->chip_type]);
1127 		retval = device_create_file(&udev->dev, &dev_attr_event_char);
1128 		if ((!retval) &&
1129 		    (priv->chip_type == FT232BM || priv->chip_type == FT2232C)) {
1130 			retval = device_create_file(&udev->dev,
1131 						    &dev_attr_latency_timer);
1132 		}
1133 	}
1134 	return retval;
1135 }
1136 
1137 static void remove_sysfs_attrs(struct usb_serial *serial)
1138 {
1139 	struct ftdi_private *priv;
1140 	struct usb_device *udev;
1141 
1142 	dbg("%s",__FUNCTION__);
1143 
1144 	priv = usb_get_serial_port_data(serial->port[0]);
1145 	udev = serial->dev;
1146 
1147 	/* XXX see create_sysfs_attrs */
1148 	if (priv->chip_type != SIO) {
1149 		device_remove_file(&udev->dev, &dev_attr_event_char);
1150 		if (priv->chip_type == FT232BM || priv->chip_type == FT2232C) {
1151 			device_remove_file(&udev->dev, &dev_attr_latency_timer);
1152 		}
1153 	}
1154 
1155 }
1156 
1157 /*
1158  * ***************************************************************************
1159  * FTDI driver specific functions
1160  * ***************************************************************************
1161  */
1162 
1163 /* Probe function to check for special devices */
1164 static int ftdi_sio_probe (struct usb_serial *serial, const struct usb_device_id *id)
1165 {
1166 	usb_set_serial_data(serial, (void *)id->driver_info);
1167 
1168 	return (0);
1169 }
1170 
1171 /* attach subroutine */
1172 static int ftdi_sio_attach (struct usb_serial *serial)
1173 {
1174 	struct usb_serial_port *port = serial->port[0];
1175 	struct ftdi_private *priv;
1176 	struct ftdi_sio_quirk *quirk;
1177 	int retval;
1178 
1179 	dbg("%s",__FUNCTION__);
1180 
1181 	priv = kzalloc(sizeof(struct ftdi_private), GFP_KERNEL);
1182 	if (!priv){
1183 		err("%s- kmalloc(%Zd) failed.", __FUNCTION__, sizeof(struct ftdi_private));
1184 		return -ENOMEM;
1185 	}
1186 
1187 	spin_lock_init(&priv->rx_lock);
1188 	spin_lock_init(&priv->tx_lock);
1189         init_waitqueue_head(&priv->delta_msr_wait);
1190 	/* This will push the characters through immediately rather
1191 	   than queue a task to deliver them */
1192 	priv->flags = ASYNC_LOW_LATENCY;
1193 
1194 	/* Increase the size of read buffers */
1195 	kfree(port->bulk_in_buffer);
1196 	port->bulk_in_buffer = kmalloc (BUFSZ, GFP_KERNEL);
1197 	if (!port->bulk_in_buffer) {
1198 		kfree (priv);
1199 		return -ENOMEM;
1200 	}
1201 	if (port->read_urb) {
1202 		port->read_urb->transfer_buffer = port->bulk_in_buffer;
1203 		port->read_urb->transfer_buffer_length = BUFSZ;
1204 	}
1205 
1206 	INIT_DELAYED_WORK(&priv->rx_work, ftdi_process_read);
1207 	priv->port = port;
1208 
1209 	/* Free port's existing write urb and transfer buffer. */
1210 	if (port->write_urb) {
1211 		usb_free_urb (port->write_urb);
1212 		port->write_urb = NULL;
1213 	}
1214 	kfree(port->bulk_out_buffer);
1215 	port->bulk_out_buffer = NULL;
1216 
1217 	usb_set_serial_port_data(serial->port[0], priv);
1218 
1219 	ftdi_determine_type (serial->port[0]);
1220 	retval = create_sysfs_attrs(serial);
1221 	if (retval)
1222 		dev_err(&serial->dev->dev, "Error creating sysfs files, "
1223 			"continuing\n");
1224 
1225 	/* Check for device requiring special set up. */
1226 	quirk = (struct ftdi_sio_quirk *)usb_get_serial_data(serial);
1227 	if (quirk && quirk->setup) {
1228 		quirk->setup(serial);
1229 	}
1230 
1231 	return 0;
1232 } /* ftdi_sio_attach */
1233 
1234 
1235 /* Setup for the USB-UIRT device, which requires hardwired
1236  * baudrate (38400 gets mapped to 312500) */
1237 /* Called from usbserial:serial_probe */
1238 static void ftdi_USB_UIRT_setup (struct usb_serial *serial)
1239 {
1240 	struct ftdi_private *priv;
1241 
1242 	dbg("%s",__FUNCTION__);
1243 
1244 	priv = usb_get_serial_port_data(serial->port[0]);
1245 	priv->flags |= ASYNC_SPD_CUST;
1246 	priv->custom_divisor = 77;
1247 	priv->force_baud = B38400;
1248 } /* ftdi_USB_UIRT_setup */
1249 
1250 /* Setup for the HE-TIRA1 device, which requires hardwired
1251  * baudrate (38400 gets mapped to 100000) and RTS-CTS enabled.  */
1252 static void ftdi_HE_TIRA1_setup (struct usb_serial *serial)
1253 {
1254 	struct ftdi_private *priv;
1255 
1256 	dbg("%s",__FUNCTION__);
1257 
1258 	priv = usb_get_serial_port_data(serial->port[0]);
1259 	priv->flags |= ASYNC_SPD_CUST;
1260 	priv->custom_divisor = 240;
1261 	priv->force_baud = B38400;
1262 	priv->force_rtscts = 1;
1263 } /* ftdi_HE_TIRA1_setup */
1264 
1265 
1266 /* ftdi_shutdown is called from usbserial:usb_serial_disconnect
1267  *   it is called when the usb device is disconnected
1268  *
1269  *   usbserial:usb_serial_disconnect
1270  *      calls __serial_close for each open of the port
1271  *      shutdown is called then (ie ftdi_shutdown)
1272  */
1273 
1274 
1275 static void ftdi_shutdown (struct usb_serial *serial)
1276 { /* ftdi_shutdown */
1277 
1278 	struct usb_serial_port *port = serial->port[0];
1279 	struct ftdi_private *priv = usb_get_serial_port_data(port);
1280 
1281 	dbg("%s", __FUNCTION__);
1282 
1283 	remove_sysfs_attrs(serial);
1284 
1285 	/* all open ports are closed at this point
1286          *    (by usbserial.c:__serial_close, which calls ftdi_close)
1287 	 */
1288 
1289 	if (priv) {
1290 		usb_set_serial_port_data(port, NULL);
1291 		kfree(priv);
1292 	}
1293 } /* ftdi_shutdown */
1294 
1295 
1296 static int  ftdi_open (struct usb_serial_port *port, struct file *filp)
1297 { /* ftdi_open */
1298 	struct usb_device *dev = port->serial->dev;
1299 	struct ftdi_private *priv = usb_get_serial_port_data(port);
1300 	unsigned long flags;
1301 
1302 	int result = 0;
1303 	char buf[1]; /* Needed for the usb_control_msg I think */
1304 
1305 	dbg("%s", __FUNCTION__);
1306 
1307 	spin_lock_irqsave(&priv->tx_lock, flags);
1308 	priv->tx_bytes = 0;
1309 	spin_unlock_irqrestore(&priv->tx_lock, flags);
1310 	spin_lock_irqsave(&priv->rx_lock, flags);
1311 	priv->rx_bytes = 0;
1312 	spin_unlock_irqrestore(&priv->rx_lock, flags);
1313 
1314 	if (port->tty)
1315 		port->tty->low_latency = (priv->flags & ASYNC_LOW_LATENCY) ? 1 : 0;
1316 
1317 	/* No error checking for this (will get errors later anyway) */
1318 	/* See ftdi_sio.h for description of what is reset */
1319 	usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
1320 			FTDI_SIO_RESET_REQUEST, FTDI_SIO_RESET_REQUEST_TYPE,
1321 			FTDI_SIO_RESET_SIO,
1322 			priv->interface, buf, 0, WDR_TIMEOUT);
1323 
1324 	/* Termios defaults are set by usb_serial_init. We don't change
1325 	   port->tty->termios - this would loose speed settings, etc.
1326 	   This is same behaviour as serial.c/rs_open() - Kuba */
1327 
1328 	/* ftdi_set_termios  will send usb control messages */
1329 	if (port->tty)
1330 		ftdi_set_termios(port, NULL);
1331 
1332 	/* FIXME: Flow control might be enabled, so it should be checked -
1333 	   we have no control of defaults! */
1334 	/* Turn on RTS and DTR since we are not flow controlling by default */
1335 	set_mctrl(port, TIOCM_DTR | TIOCM_RTS);
1336 
1337 	/* Not throttled */
1338 	spin_lock_irqsave(&priv->rx_lock, flags);
1339 	priv->rx_flags &= ~(THROTTLED | ACTUALLY_THROTTLED);
1340 	spin_unlock_irqrestore(&priv->rx_lock, flags);
1341 
1342 	/* Start reading from the device */
1343 	priv->rx_processed = 0;
1344 	usb_fill_bulk_urb(port->read_urb, dev,
1345 		      usb_rcvbulkpipe(dev, port->bulk_in_endpointAddress),
1346 		      port->read_urb->transfer_buffer, port->read_urb->transfer_buffer_length,
1347 		      ftdi_read_bulk_callback, port);
1348 	result = usb_submit_urb(port->read_urb, GFP_KERNEL);
1349 	if (result)
1350 		err("%s - failed submitting read urb, error %d", __FUNCTION__, result);
1351 
1352 
1353 	return result;
1354 } /* ftdi_open */
1355 
1356 
1357 
1358 /*
1359  * usbserial:__serial_close  only calls ftdi_close if the point is open
1360  *
1361  *   This only gets called when it is the last close
1362  *
1363  *
1364  */
1365 
1366 static void ftdi_close (struct usb_serial_port *port, struct file *filp)
1367 { /* ftdi_close */
1368 	unsigned int c_cflag = port->tty->termios->c_cflag;
1369 	struct ftdi_private *priv = usb_get_serial_port_data(port);
1370 	char buf[1];
1371 
1372 	dbg("%s", __FUNCTION__);
1373 
1374 	if (c_cflag & HUPCL){
1375 		/* Disable flow control */
1376 		if (usb_control_msg(port->serial->dev,
1377 				    usb_sndctrlpipe(port->serial->dev, 0),
1378 				    FTDI_SIO_SET_FLOW_CTRL_REQUEST,
1379 				    FTDI_SIO_SET_FLOW_CTRL_REQUEST_TYPE,
1380 				    0, priv->interface, buf, 0,
1381 				    WDR_TIMEOUT) < 0) {
1382 			err("error from flowcontrol urb");
1383 		}
1384 
1385 		/* drop RTS and DTR */
1386 		clear_mctrl(port, TIOCM_DTR | TIOCM_RTS);
1387 	} /* Note change no line if hupcl is off */
1388 
1389 	/* cancel any scheduled reading */
1390 	cancel_delayed_work(&priv->rx_work);
1391 	flush_scheduled_work();
1392 
1393 	/* shutdown our bulk read */
1394 	usb_kill_urb(port->read_urb);
1395 } /* ftdi_close */
1396 
1397 
1398 
1399 /* The SIO requires the first byte to have:
1400  *  B0 1
1401  *  B1 0
1402  *  B2..7 length of message excluding byte 0
1403  *
1404  * The new devices do not require this byte
1405  */
1406 static int ftdi_write (struct usb_serial_port *port,
1407 			   const unsigned char *buf, int count)
1408 { /* ftdi_write */
1409 	struct ftdi_private *priv = usb_get_serial_port_data(port);
1410 	struct urb *urb;
1411 	unsigned char *buffer;
1412 	int data_offset ;       /* will be 1 for the SIO and 0 otherwise */
1413 	int status;
1414 	int transfer_size;
1415 	unsigned long flags;
1416 
1417 	dbg("%s port %d, %d bytes", __FUNCTION__, port->number, count);
1418 
1419 	if (count == 0) {
1420 		dbg("write request of 0 bytes");
1421 		return 0;
1422 	}
1423 	spin_lock_irqsave(&priv->tx_lock, flags);
1424 	if (priv->tx_outstanding_urbs > URB_UPPER_LIMIT) {
1425 		spin_unlock_irqrestore(&priv->tx_lock, flags);
1426 		dbg("%s - write limit hit\n", __FUNCTION__);
1427 		return 0;
1428 	}
1429 	spin_unlock_irqrestore(&priv->tx_lock, flags);
1430 
1431 	data_offset = priv->write_offset;
1432         dbg("data_offset set to %d",data_offset);
1433 
1434 	/* Determine total transfer size */
1435 	transfer_size = count;
1436 	if (data_offset > 0) {
1437 		/* Original sio needs control bytes too... */
1438 		transfer_size += (data_offset *
1439 				((count + (PKTSZ - 1 - data_offset)) /
1440 				 (PKTSZ - data_offset)));
1441 	}
1442 
1443 	buffer = kmalloc (transfer_size, GFP_ATOMIC);
1444 	if (!buffer) {
1445 		err("%s ran out of kernel memory for urb ...", __FUNCTION__);
1446 		return -ENOMEM;
1447 	}
1448 
1449 	urb = usb_alloc_urb(0, GFP_ATOMIC);
1450 	if (!urb) {
1451 		err("%s - no more free urbs", __FUNCTION__);
1452 		kfree (buffer);
1453 		return -ENOMEM;
1454 	}
1455 
1456 	/* Copy data */
1457 	if (data_offset > 0) {
1458 		/* Original sio requires control byte at start of each packet. */
1459 		int user_pktsz = PKTSZ - data_offset;
1460 		int todo = count;
1461 		unsigned char *first_byte = buffer;
1462 		const unsigned char *current_position = buf;
1463 
1464 		while (todo > 0) {
1465 			if (user_pktsz > todo) {
1466 				user_pktsz = todo;
1467 			}
1468 			/* Write the control byte at the front of the packet*/
1469 			*first_byte = 1 | ((user_pktsz) << 2);
1470 			/* Copy data for packet */
1471 			memcpy (first_byte + data_offset,
1472 				current_position, user_pktsz);
1473 			first_byte += user_pktsz + data_offset;
1474 			current_position += user_pktsz;
1475 			todo -= user_pktsz;
1476 		}
1477 	} else {
1478 		/* No control byte required. */
1479 		/* Copy in the data to send */
1480 		memcpy (buffer, buf, count);
1481 	}
1482 
1483 	usb_serial_debug_data(debug, &port->dev, __FUNCTION__, transfer_size, buffer);
1484 
1485 	/* fill the buffer and send it */
1486 	usb_fill_bulk_urb(urb, port->serial->dev,
1487 		      usb_sndbulkpipe(port->serial->dev, port->bulk_out_endpointAddress),
1488 		      buffer, transfer_size,
1489 		      ftdi_write_bulk_callback, port);
1490 
1491 	status = usb_submit_urb(urb, GFP_ATOMIC);
1492 	if (status) {
1493 		err("%s - failed submitting write urb, error %d", __FUNCTION__, status);
1494 		count = status;
1495 		kfree (buffer);
1496 	} else {
1497 		spin_lock_irqsave(&priv->tx_lock, flags);
1498 		++priv->tx_outstanding_urbs;
1499 		priv->tx_outstanding_bytes += count;
1500 		priv->tx_bytes += count;
1501 		spin_unlock_irqrestore(&priv->tx_lock, flags);
1502 	}
1503 
1504 	/* we are done with this urb, so let the host driver
1505 	 * really free it when it is finished with it */
1506 	usb_free_urb (urb);
1507 
1508 	dbg("%s write returning: %d", __FUNCTION__, count);
1509 	return count;
1510 } /* ftdi_write */
1511 
1512 
1513 /* This function may get called when the device is closed */
1514 
1515 static void ftdi_write_bulk_callback (struct urb *urb)
1516 {
1517 	unsigned long flags;
1518 	struct usb_serial_port *port = (struct usb_serial_port *)urb->context;
1519 	struct ftdi_private *priv;
1520 	int data_offset;       /* will be 1 for the SIO and 0 otherwise */
1521 	unsigned long countback;
1522 
1523 	/* free up the transfer buffer, as usb_free_urb() does not do this */
1524 	kfree (urb->transfer_buffer);
1525 
1526 	dbg("%s - port %d", __FUNCTION__, port->number);
1527 
1528 	if (urb->status) {
1529 		dbg("nonzero write bulk status received: %d", urb->status);
1530 		return;
1531 	}
1532 
1533 	priv = usb_get_serial_port_data(port);
1534 	if (!priv) {
1535 		dbg("%s - bad port private data pointer - exiting", __FUNCTION__);
1536 		return;
1537 	}
1538 	/* account for transferred data */
1539 	countback = urb->actual_length;
1540 	data_offset = priv->write_offset;
1541 	if (data_offset > 0) {
1542 		/* Subtract the control bytes */
1543 		countback -= (data_offset * ((countback + (PKTSZ - 1)) / PKTSZ));
1544 	}
1545 	spin_lock_irqsave(&priv->tx_lock, flags);
1546 	--priv->tx_outstanding_urbs;
1547 	priv->tx_outstanding_bytes -= countback;
1548 	spin_unlock_irqrestore(&priv->tx_lock, flags);
1549 
1550 	usb_serial_port_softint(port);
1551 } /* ftdi_write_bulk_callback */
1552 
1553 
1554 static int ftdi_write_room( struct usb_serial_port *port )
1555 {
1556 	struct ftdi_private *priv = usb_get_serial_port_data(port);
1557 	int room;
1558 	unsigned long flags;
1559 
1560 	dbg("%s - port %d", __FUNCTION__, port->number);
1561 
1562 	spin_lock_irqsave(&priv->tx_lock, flags);
1563 	if (priv->tx_outstanding_urbs < URB_UPPER_LIMIT) {
1564 		/*
1565 		 * We really can take anything the user throws at us
1566 		 * but let's pick a nice big number to tell the tty
1567 		 * layer that we have lots of free space
1568 		 */
1569 		room = 2048;
1570 	} else {
1571 		room = 0;
1572 	}
1573 	spin_unlock_irqrestore(&priv->tx_lock, flags);
1574 	return room;
1575 } /* ftdi_write_room */
1576 
1577 
1578 static int ftdi_chars_in_buffer (struct usb_serial_port *port)
1579 { /* ftdi_chars_in_buffer */
1580 	struct ftdi_private *priv = usb_get_serial_port_data(port);
1581 	int buffered;
1582 	unsigned long flags;
1583 
1584 	dbg("%s - port %d", __FUNCTION__, port->number);
1585 
1586 	spin_lock_irqsave(&priv->tx_lock, flags);
1587 	buffered = (int)priv->tx_outstanding_bytes;
1588 	spin_unlock_irqrestore(&priv->tx_lock, flags);
1589 	if (buffered < 0) {
1590 		err("%s outstanding tx bytes is negative!", __FUNCTION__);
1591 		buffered = 0;
1592 	}
1593 	return buffered;
1594 } /* ftdi_chars_in_buffer */
1595 
1596 
1597 
1598 static void ftdi_read_bulk_callback (struct urb *urb)
1599 { /* ftdi_read_bulk_callback */
1600 	struct usb_serial_port *port = (struct usb_serial_port *)urb->context;
1601 	struct tty_struct *tty;
1602 	struct ftdi_private *priv;
1603 	unsigned long countread;
1604 	unsigned long flags;
1605 
1606 	if (urb->number_of_packets > 0) {
1607 		err("%s transfer_buffer_length %d actual_length %d number of packets %d",__FUNCTION__,
1608 		    urb->transfer_buffer_length, urb->actual_length, urb->number_of_packets );
1609 		err("%s transfer_flags %x ", __FUNCTION__,urb->transfer_flags );
1610 	}
1611 
1612 	dbg("%s - port %d", __FUNCTION__, port->number);
1613 
1614 	if (port->open_count <= 0)
1615 		return;
1616 
1617 	tty = port->tty;
1618 	if (!tty) {
1619 		dbg("%s - bad tty pointer - exiting",__FUNCTION__);
1620 		return;
1621 	}
1622 
1623 	priv = usb_get_serial_port_data(port);
1624 	if (!priv) {
1625 		dbg("%s - bad port private data pointer - exiting", __FUNCTION__);
1626 		return;
1627 	}
1628 
1629 	if (urb != port->read_urb) {
1630 		err("%s - Not my urb!", __FUNCTION__);
1631 	}
1632 
1633 	if (urb->status) {
1634 		/* This will happen at close every time so it is a dbg not an err */
1635 		dbg("(this is ok on close) nonzero read bulk status received: %d", urb->status);
1636 		return;
1637 	}
1638 
1639 	/* count data bytes, but not status bytes */
1640 	countread = urb->actual_length;
1641 	countread -= 2 * ((countread + (PKTSZ - 1)) / PKTSZ);
1642 	spin_lock_irqsave(&priv->rx_lock, flags);
1643 	priv->rx_bytes += countread;
1644 	spin_unlock_irqrestore(&priv->rx_lock, flags);
1645 
1646 	ftdi_process_read(&priv->rx_work.work);
1647 
1648 } /* ftdi_read_bulk_callback */
1649 
1650 
1651 static void ftdi_process_read (struct work_struct *work)
1652 { /* ftdi_process_read */
1653 	struct ftdi_private *priv =
1654 		container_of(work, struct ftdi_private, rx_work.work);
1655 	struct usb_serial_port *port = priv->port;
1656 	struct urb *urb;
1657 	struct tty_struct *tty;
1658 	char error_flag;
1659 	unsigned char *data;
1660 
1661 	int i;
1662 	int result;
1663 	int need_flip;
1664 	int packet_offset;
1665 	unsigned long flags;
1666 
1667 	dbg("%s - port %d", __FUNCTION__, port->number);
1668 
1669 	if (port->open_count <= 0)
1670 		return;
1671 
1672 	tty = port->tty;
1673 	if (!tty) {
1674 		dbg("%s - bad tty pointer - exiting",__FUNCTION__);
1675 		return;
1676 	}
1677 
1678 	priv = usb_get_serial_port_data(port);
1679 	if (!priv) {
1680 		dbg("%s - bad port private data pointer - exiting", __FUNCTION__);
1681 		return;
1682 	}
1683 
1684 	urb = port->read_urb;
1685 	if (!urb) {
1686 		dbg("%s - bad read_urb pointer - exiting", __FUNCTION__);
1687 		return;
1688 	}
1689 
1690 	data = urb->transfer_buffer;
1691 
1692 	if (priv->rx_processed) {
1693 		dbg("%s - already processed: %d bytes, %d remain", __FUNCTION__,
1694 				priv->rx_processed,
1695 				urb->actual_length - priv->rx_processed);
1696 	} else {
1697 		/* The first two bytes of every read packet are status */
1698 		if (urb->actual_length > 2) {
1699 			usb_serial_debug_data(debug, &port->dev, __FUNCTION__, urb->actual_length, data);
1700 		} else {
1701 			dbg("Status only: %03oo %03oo",data[0],data[1]);
1702 		}
1703 	}
1704 
1705 
1706 	/* TO DO -- check for hung up line and handle appropriately: */
1707 	/*   send hangup  */
1708 	/* See acm.c - you do a tty_hangup  - eg tty_hangup(tty) */
1709 	/* if CD is dropped and the line is not CLOCAL then we should hangup */
1710 
1711 	need_flip = 0;
1712 	for (packet_offset = priv->rx_processed; packet_offset < urb->actual_length; packet_offset += PKTSZ) {
1713 		int length;
1714 
1715 		/* Compare new line status to the old one, signal if different */
1716 		/* N.B. packet may be processed more than once, but differences
1717 		 * are only processed once.  */
1718 		if (priv != NULL) {
1719 			char new_status = data[packet_offset+0] & FTDI_STATUS_B0_MASK;
1720 			if (new_status != priv->prev_status) {
1721 				priv->diff_status |= new_status ^ priv->prev_status;
1722 				wake_up_interruptible(&priv->delta_msr_wait);
1723 				priv->prev_status = new_status;
1724 			}
1725 		}
1726 
1727 		length = min(PKTSZ, urb->actual_length-packet_offset)-2;
1728 		if (length < 0) {
1729 			err("%s - bad packet length: %d", __FUNCTION__, length+2);
1730 			length = 0;
1731 		}
1732 
1733 		if (priv->rx_flags & THROTTLED) {
1734 			dbg("%s - throttled", __FUNCTION__);
1735 			break;
1736 		}
1737 		if (tty_buffer_request_room(tty, length) < length) {
1738 			/* break out & wait for throttling/unthrottling to happen */
1739 			dbg("%s - receive room low", __FUNCTION__);
1740 			break;
1741 		}
1742 
1743 		/* Handle errors and break */
1744 		error_flag = TTY_NORMAL;
1745 		/* Although the device uses a bitmask and hence can have multiple */
1746 		/* errors on a packet - the order here sets the priority the */
1747 		/* error is returned to the tty layer  */
1748 
1749 		if ( data[packet_offset+1] & FTDI_RS_OE ) {
1750 			error_flag = TTY_OVERRUN;
1751 			dbg("OVERRRUN error");
1752 		}
1753 		if ( data[packet_offset+1] & FTDI_RS_BI ) {
1754 			error_flag = TTY_BREAK;
1755 			dbg("BREAK received");
1756 		}
1757 		if ( data[packet_offset+1] & FTDI_RS_PE ) {
1758 			error_flag = TTY_PARITY;
1759 			dbg("PARITY error");
1760 		}
1761 		if ( data[packet_offset+1] & FTDI_RS_FE ) {
1762 			error_flag = TTY_FRAME;
1763 			dbg("FRAMING error");
1764 		}
1765 		if (length > 0) {
1766 			for (i = 2; i < length+2; i++) {
1767 				/* Note that the error flag is duplicated for
1768 				   every character received since we don't know
1769 				   which character it applied to */
1770 				tty_insert_flip_char(tty, data[packet_offset+i], error_flag);
1771 			}
1772 			need_flip = 1;
1773 		}
1774 
1775 #ifdef NOT_CORRECT_BUT_KEEPING_IT_FOR_NOW
1776 		/* if a parity error is detected you get status packets forever
1777 		   until a character is sent without a parity error.
1778 		   This doesn't work well since the application receives a never
1779 		   ending stream of bad data - even though new data hasn't been sent.
1780 		   Therefore I (bill) have taken this out.
1781 		   However - this might make sense for framing errors and so on
1782 		   so I am leaving the code in for now.
1783 		*/
1784 		else {
1785 			if (error_flag != TTY_NORMAL){
1786 				dbg("error_flag is not normal");
1787 				/* In this case it is just status - if that is an error send a bad character */
1788 				if(tty->flip.count >= TTY_FLIPBUF_SIZE) {
1789 					tty_flip_buffer_push(tty);
1790 				}
1791 				tty_insert_flip_char(tty, 0xff, error_flag);
1792 				need_flip = 1;
1793 			}
1794 		}
1795 #endif
1796 	} /* "for(packet_offset=0..." */
1797 
1798 	/* Low latency */
1799 	if (need_flip) {
1800 		tty_flip_buffer_push(tty);
1801 	}
1802 
1803 	if (packet_offset < urb->actual_length) {
1804 		/* not completely processed - record progress */
1805 		priv->rx_processed = packet_offset;
1806 		dbg("%s - incomplete, %d bytes processed, %d remain",
1807 				__FUNCTION__, packet_offset,
1808 				urb->actual_length - packet_offset);
1809 		/* check if we were throttled while processing */
1810 		spin_lock_irqsave(&priv->rx_lock, flags);
1811 		if (priv->rx_flags & THROTTLED) {
1812 			priv->rx_flags |= ACTUALLY_THROTTLED;
1813 			spin_unlock_irqrestore(&priv->rx_lock, flags);
1814 			dbg("%s - deferring remainder until unthrottled",
1815 					__FUNCTION__);
1816 			return;
1817 		}
1818 		spin_unlock_irqrestore(&priv->rx_lock, flags);
1819 		/* if the port is closed stop trying to read */
1820 		if (port->open_count > 0){
1821 			/* delay processing of remainder */
1822 			schedule_delayed_work(&priv->rx_work, 1);
1823 		} else {
1824 			dbg("%s - port is closed", __FUNCTION__);
1825 		}
1826 		return;
1827 	}
1828 
1829 	/* urb is completely processed */
1830 	priv->rx_processed = 0;
1831 
1832 	/* if the port is closed stop trying to read */
1833 	if (port->open_count > 0){
1834 		/* Continue trying to always read  */
1835 		usb_fill_bulk_urb(port->read_urb, port->serial->dev,
1836 			      usb_rcvbulkpipe(port->serial->dev, port->bulk_in_endpointAddress),
1837 			      port->read_urb->transfer_buffer, port->read_urb->transfer_buffer_length,
1838 			      ftdi_read_bulk_callback, port);
1839 
1840 		result = usb_submit_urb(port->read_urb, GFP_ATOMIC);
1841 		if (result)
1842 			err("%s - failed resubmitting read urb, error %d", __FUNCTION__, result);
1843 	}
1844 
1845 	return;
1846 } /* ftdi_process_read */
1847 
1848 
1849 static void ftdi_break_ctl( struct usb_serial_port *port, int break_state )
1850 {
1851 	struct ftdi_private *priv = usb_get_serial_port_data(port);
1852 	__u16 urb_value = 0;
1853 	char buf[1];
1854 
1855 	/* break_state = -1 to turn on break, and 0 to turn off break */
1856 	/* see drivers/char/tty_io.c to see it used */
1857 	/* last_set_data_urb_value NEVER has the break bit set in it */
1858 
1859 	if (break_state) {
1860 		urb_value = priv->last_set_data_urb_value | FTDI_SIO_SET_BREAK;
1861 	} else {
1862 		urb_value = priv->last_set_data_urb_value;
1863 	}
1864 
1865 
1866 	if (usb_control_msg(port->serial->dev, usb_sndctrlpipe(port->serial->dev, 0),
1867 			    FTDI_SIO_SET_DATA_REQUEST,
1868 			    FTDI_SIO_SET_DATA_REQUEST_TYPE,
1869 			    urb_value , priv->interface,
1870 			    buf, 0, WDR_TIMEOUT) < 0) {
1871 		err("%s FAILED to enable/disable break state (state was %d)", __FUNCTION__,break_state);
1872 	}
1873 
1874 	dbg("%s break state is %d - urb is %d", __FUNCTION__,break_state, urb_value);
1875 
1876 }
1877 
1878 
1879 /* old_termios contains the original termios settings and tty->termios contains
1880  * the new setting to be used
1881  * WARNING: set_termios calls this with old_termios in kernel space
1882  */
1883 
1884 static void ftdi_set_termios (struct usb_serial_port *port, struct ktermios *old_termios)
1885 { /* ftdi_termios */
1886 	struct usb_device *dev = port->serial->dev;
1887 	unsigned int cflag = port->tty->termios->c_cflag;
1888 	struct ftdi_private *priv = usb_get_serial_port_data(port);
1889 	__u16 urb_value; /* will hold the new flags */
1890 	char buf[1]; /* Perhaps I should dynamically alloc this? */
1891 
1892 	// Added for xon/xoff support
1893 	unsigned int iflag = port->tty->termios->c_iflag;
1894 	unsigned char vstop;
1895 	unsigned char vstart;
1896 
1897 	dbg("%s", __FUNCTION__);
1898 
1899 	/* Force baud rate if this device requires it, unless it is set to B0. */
1900 	if (priv->force_baud && ((port->tty->termios->c_cflag & CBAUD) != B0)) {
1901 		dbg("%s: forcing baud rate for this device", __FUNCTION__);
1902 		port->tty->termios->c_cflag &= ~CBAUD;
1903 		port->tty->termios->c_cflag |= priv->force_baud;
1904 	}
1905 
1906 	/* Force RTS-CTS if this device requires it. */
1907 	if (priv->force_rtscts) {
1908 		dbg("%s: forcing rtscts for this device", __FUNCTION__);
1909 		port->tty->termios->c_cflag |= CRTSCTS;
1910 	}
1911 
1912 	cflag = port->tty->termios->c_cflag;
1913 
1914 	/* FIXME -For this cut I don't care if the line is really changing or
1915 	   not  - so just do the change regardless  - should be able to
1916 	   compare old_termios and tty->termios */
1917 	/* NOTE These routines can get interrupted by
1918 	   ftdi_sio_read_bulk_callback  - need to examine what this
1919            means - don't see any problems yet */
1920 
1921 	/* Set number of data bits, parity, stop bits */
1922 
1923 	urb_value = 0;
1924 	urb_value |= (cflag & CSTOPB ? FTDI_SIO_SET_DATA_STOP_BITS_2 :
1925 		      FTDI_SIO_SET_DATA_STOP_BITS_1);
1926 	urb_value |= (cflag & PARENB ?
1927 		      (cflag & PARODD ? FTDI_SIO_SET_DATA_PARITY_ODD :
1928 		       FTDI_SIO_SET_DATA_PARITY_EVEN) :
1929 		      FTDI_SIO_SET_DATA_PARITY_NONE);
1930 	if (cflag & CSIZE) {
1931 		switch (cflag & CSIZE) {
1932 		case CS5: urb_value |= 5; dbg("Setting CS5"); break;
1933 		case CS6: urb_value |= 6; dbg("Setting CS6"); break;
1934 		case CS7: urb_value |= 7; dbg("Setting CS7"); break;
1935 		case CS8: urb_value |= 8; dbg("Setting CS8"); break;
1936 		default:
1937 			err("CSIZE was set but not CS5-CS8");
1938 		}
1939 	}
1940 
1941 	/* This is needed by the break command since it uses the same command - but is
1942 	 *  or'ed with this value  */
1943 	priv->last_set_data_urb_value = urb_value;
1944 
1945 	if (usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
1946 			    FTDI_SIO_SET_DATA_REQUEST,
1947 			    FTDI_SIO_SET_DATA_REQUEST_TYPE,
1948 			    urb_value , priv->interface,
1949 			    buf, 0, WDR_SHORT_TIMEOUT) < 0) {
1950 		err("%s FAILED to set databits/stopbits/parity", __FUNCTION__);
1951 	}
1952 
1953 	/* Now do the baudrate */
1954 	if ((cflag & CBAUD) == B0 ) {
1955 		/* Disable flow control */
1956 		if (usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
1957 				    FTDI_SIO_SET_FLOW_CTRL_REQUEST,
1958 				    FTDI_SIO_SET_FLOW_CTRL_REQUEST_TYPE,
1959 				    0, priv->interface,
1960 				    buf, 0, WDR_TIMEOUT) < 0) {
1961 			err("%s error from disable flowcontrol urb", __FUNCTION__);
1962 		}
1963 		/* Drop RTS and DTR */
1964 		clear_mctrl(port, TIOCM_DTR | TIOCM_RTS);
1965 	} else {
1966 		/* set the baudrate determined before */
1967 		if (change_speed(port)) {
1968 			err("%s urb failed to set baudrate", __FUNCTION__);
1969 		}
1970 		/* Ensure RTS and DTR are raised when baudrate changed from 0 */
1971 		if (!old_termios || (old_termios->c_cflag & CBAUD) == B0) {
1972 			set_mctrl(port, TIOCM_DTR | TIOCM_RTS);
1973 		}
1974 	}
1975 
1976 	/* Set flow control */
1977 	/* Note device also supports DTR/CD (ugh) and Xon/Xoff in hardware */
1978 	if (cflag & CRTSCTS) {
1979 		dbg("%s Setting to CRTSCTS flow control", __FUNCTION__);
1980 		if (usb_control_msg(dev,
1981 				    usb_sndctrlpipe(dev, 0),
1982 				    FTDI_SIO_SET_FLOW_CTRL_REQUEST,
1983 				    FTDI_SIO_SET_FLOW_CTRL_REQUEST_TYPE,
1984 				    0 , (FTDI_SIO_RTS_CTS_HS | priv->interface),
1985 				    buf, 0, WDR_TIMEOUT) < 0) {
1986 			err("urb failed to set to rts/cts flow control");
1987 		}
1988 
1989 	} else {
1990 		/*
1991 		 * Xon/Xoff code
1992 		 *
1993 		 * Check the IXOFF status in the iflag component of the termios structure
1994 		 * if IXOFF is not set, the pre-xon/xoff code is executed.
1995 		*/
1996 		if (iflag & IXOFF) {
1997 			dbg("%s  request to enable xonxoff iflag=%04x",__FUNCTION__,iflag);
1998 			// Try to enable the XON/XOFF on the ftdi_sio
1999 			// Set the vstart and vstop -- could have been done up above where
2000 			// a lot of other dereferencing is done but that would be very
2001 			// inefficient as vstart and vstop are not always needed
2002 			vstart=port->tty->termios->c_cc[VSTART];
2003 			vstop=port->tty->termios->c_cc[VSTOP];
2004 			urb_value=(vstop << 8) | (vstart);
2005 
2006 			if (usb_control_msg(dev,
2007 					    usb_sndctrlpipe(dev, 0),
2008 					    FTDI_SIO_SET_FLOW_CTRL_REQUEST,
2009 					    FTDI_SIO_SET_FLOW_CTRL_REQUEST_TYPE,
2010 					    urb_value , (FTDI_SIO_XON_XOFF_HS
2011 							 | priv->interface),
2012 					    buf, 0, WDR_TIMEOUT) < 0) {
2013 				err("urb failed to set to xon/xoff flow control");
2014 			}
2015 		} else {
2016 			/* else clause to only run if cfag ! CRTSCTS and iflag ! XOFF */
2017 			/* CHECKME Assuming XON/XOFF handled by tty stack - not by device */
2018 			dbg("%s Turning off hardware flow control", __FUNCTION__);
2019 			if (usb_control_msg(dev,
2020 					    usb_sndctrlpipe(dev, 0),
2021 					    FTDI_SIO_SET_FLOW_CTRL_REQUEST,
2022 					    FTDI_SIO_SET_FLOW_CTRL_REQUEST_TYPE,
2023 					    0, priv->interface,
2024 					    buf, 0, WDR_TIMEOUT) < 0) {
2025 				err("urb failed to clear flow control");
2026 			}
2027 		}
2028 
2029 	}
2030 	return;
2031 } /* ftdi_termios */
2032 
2033 
2034 static int ftdi_tiocmget (struct usb_serial_port *port, struct file *file)
2035 {
2036 	struct ftdi_private *priv = usb_get_serial_port_data(port);
2037 	unsigned char buf[2];
2038 	int ret;
2039 
2040 	dbg("%s TIOCMGET", __FUNCTION__);
2041 	switch (priv->chip_type) {
2042 	case SIO:
2043 		/* Request the status from the device */
2044 		if ((ret = usb_control_msg(port->serial->dev,
2045 					   usb_rcvctrlpipe(port->serial->dev, 0),
2046 					   FTDI_SIO_GET_MODEM_STATUS_REQUEST,
2047 					   FTDI_SIO_GET_MODEM_STATUS_REQUEST_TYPE,
2048 					   0, 0,
2049 					   buf, 1, WDR_TIMEOUT)) < 0 ) {
2050 			err("%s Could not get modem status of device - err: %d", __FUNCTION__,
2051 			    ret);
2052 			return(ret);
2053 		}
2054 		break;
2055 	case FT8U232AM:
2056 	case FT232BM:
2057 	case FT2232C:
2058 		/* the 8U232AM returns a two byte value (the sio is a 1 byte value) - in the same
2059 		   format as the data returned from the in point */
2060 		if ((ret = usb_control_msg(port->serial->dev,
2061 					   usb_rcvctrlpipe(port->serial->dev, 0),
2062 					   FTDI_SIO_GET_MODEM_STATUS_REQUEST,
2063 					   FTDI_SIO_GET_MODEM_STATUS_REQUEST_TYPE,
2064 					   0, priv->interface,
2065 					   buf, 2, WDR_TIMEOUT)) < 0 ) {
2066 			err("%s Could not get modem status of device - err: %d", __FUNCTION__,
2067 			    ret);
2068 			return(ret);
2069 		}
2070 		break;
2071 	default:
2072 		return -EFAULT;
2073 		break;
2074 	}
2075 
2076 	return  (buf[0] & FTDI_SIO_DSR_MASK ? TIOCM_DSR : 0) |
2077 		(buf[0] & FTDI_SIO_CTS_MASK ? TIOCM_CTS : 0) |
2078 		(buf[0]  & FTDI_SIO_RI_MASK  ? TIOCM_RI  : 0) |
2079 		(buf[0]  & FTDI_SIO_RLSD_MASK ? TIOCM_CD  : 0) |
2080 		priv->last_dtr_rts;
2081 }
2082 
2083 static int ftdi_tiocmset(struct usb_serial_port *port, struct file * file, unsigned int set, unsigned int clear)
2084 {
2085 	dbg("%s TIOCMSET", __FUNCTION__);
2086 	return update_mctrl(port, set, clear);
2087 }
2088 
2089 
2090 static int ftdi_ioctl (struct usb_serial_port *port, struct file * file, unsigned int cmd, unsigned long arg)
2091 {
2092 	struct ftdi_private *priv = usb_get_serial_port_data(port);
2093 
2094 	dbg("%s cmd 0x%04x", __FUNCTION__, cmd);
2095 
2096 	/* Based on code from acm.c and others */
2097 	switch (cmd) {
2098 
2099 	case TIOCGSERIAL: /* gets serial port data */
2100 		return get_serial_info(port, (struct serial_struct __user *) arg);
2101 
2102 	case TIOCSSERIAL: /* sets serial port data */
2103 		return set_serial_info(port, (struct serial_struct __user *) arg);
2104 
2105 	/*
2106 	 * Wait for any of the 4 modem inputs (DCD,RI,DSR,CTS) to change
2107 	 * - mask passed in arg for lines of interest
2108 	 *   (use |'ed TIOCM_RNG/DSR/CD/CTS for masking)
2109 	 * Caller should use TIOCGICOUNT to see which one it was.
2110 	 *
2111 	 * This code is borrowed from linux/drivers/char/serial.c
2112 	 */
2113 	case TIOCMIWAIT:
2114 		while (priv != NULL) {
2115 			interruptible_sleep_on(&priv->delta_msr_wait);
2116 			/* see if a signal did it */
2117 			if (signal_pending(current))
2118 				return -ERESTARTSYS;
2119 			else {
2120 				char diff = priv->diff_status;
2121 
2122 				if (diff == 0) {
2123 					return -EIO; /* no change => error */
2124 				}
2125 
2126 				/* Consume all events */
2127 				priv->diff_status = 0;
2128 
2129 				/* Return 0 if caller wanted to know about these bits */
2130 				if ( ((arg & TIOCM_RNG) && (diff & FTDI_RS0_RI)) ||
2131 				     ((arg & TIOCM_DSR) && (diff & FTDI_RS0_DSR)) ||
2132 				     ((arg & TIOCM_CD)  && (diff & FTDI_RS0_RLSD)) ||
2133 				     ((arg & TIOCM_CTS) && (diff & FTDI_RS0_CTS)) ) {
2134 					return 0;
2135 				}
2136 				/*
2137 				 * Otherwise caller can't care less about what happened,
2138 				 * and so we continue to wait for more events.
2139 				 */
2140 			}
2141 		}
2142 		return(0);
2143 		break;
2144 	default:
2145 		break;
2146 
2147 	}
2148 
2149 
2150 	/* This is not necessarily an error - turns out the higher layers will do
2151 	 *  some ioctls itself (see comment above)
2152 	 */
2153 	dbg("%s arg not supported - it was 0x%04x - check /usr/include/asm/ioctls.h", __FUNCTION__, cmd);
2154 
2155 	return(-ENOIOCTLCMD);
2156 } /* ftdi_ioctl */
2157 
2158 
2159 static void ftdi_throttle (struct usb_serial_port *port)
2160 {
2161 	struct ftdi_private *priv = usb_get_serial_port_data(port);
2162 	unsigned long flags;
2163 
2164 	dbg("%s - port %d", __FUNCTION__, port->number);
2165 
2166 	spin_lock_irqsave(&priv->rx_lock, flags);
2167 	priv->rx_flags |= THROTTLED;
2168 	spin_unlock_irqrestore(&priv->rx_lock, flags);
2169 }
2170 
2171 
2172 static void ftdi_unthrottle (struct usb_serial_port *port)
2173 {
2174 	struct ftdi_private *priv = usb_get_serial_port_data(port);
2175 	int actually_throttled;
2176 	unsigned long flags;
2177 
2178 	dbg("%s - port %d", __FUNCTION__, port->number);
2179 
2180 	spin_lock_irqsave(&priv->rx_lock, flags);
2181 	actually_throttled = priv->rx_flags & ACTUALLY_THROTTLED;
2182 	priv->rx_flags &= ~(THROTTLED | ACTUALLY_THROTTLED);
2183 	spin_unlock_irqrestore(&priv->rx_lock, flags);
2184 
2185 	if (actually_throttled)
2186 		schedule_delayed_work(&priv->rx_work, 0);
2187 }
2188 
2189 static int __init ftdi_init (void)
2190 {
2191 	int retval;
2192 
2193 	dbg("%s", __FUNCTION__);
2194 	if (vendor > 0 && product > 0) {
2195 		/* Add user specified VID/PID to reserved element of table. */
2196 		int i;
2197 		for (i = 0; id_table_combined[i].idVendor; i++)
2198 			;
2199 		id_table_combined[i].match_flags = USB_DEVICE_ID_MATCH_DEVICE;
2200 		id_table_combined[i].idVendor = vendor;
2201 		id_table_combined[i].idProduct = product;
2202 	}
2203 	retval = usb_serial_register(&ftdi_sio_device);
2204 	if (retval)
2205 		goto failed_sio_register;
2206 	retval = usb_register(&ftdi_driver);
2207 	if (retval)
2208 		goto failed_usb_register;
2209 
2210 	info(DRIVER_VERSION ":" DRIVER_DESC);
2211 	return 0;
2212 failed_usb_register:
2213 	usb_serial_deregister(&ftdi_sio_device);
2214 failed_sio_register:
2215 	return retval;
2216 }
2217 
2218 
2219 static void __exit ftdi_exit (void)
2220 {
2221 
2222 	dbg("%s", __FUNCTION__);
2223 
2224 	usb_deregister (&ftdi_driver);
2225 	usb_serial_deregister (&ftdi_sio_device);
2226 
2227 }
2228 
2229 
2230 module_init(ftdi_init);
2231 module_exit(ftdi_exit);
2232 
2233 MODULE_AUTHOR( DRIVER_AUTHOR );
2234 MODULE_DESCRIPTION( DRIVER_DESC );
2235 MODULE_LICENSE("GPL");
2236 
2237 module_param(debug, bool, S_IRUGO | S_IWUSR);
2238 MODULE_PARM_DESC(debug, "Debug enabled or not");
2239 module_param(vendor, ushort, 0);
2240 MODULE_PARM_DESC(vendor, "User specified vendor ID (default="
2241 		__MODULE_STRING(FTDI_VID)")");
2242 module_param(product, ushort, 0);
2243 MODULE_PARM_DESC(vendor, "User specified product ID");
2244 
2245