xref: /linux/drivers/usb/serial/ftdi_sio.c (revision 9ce7677cfd7cd871adb457c80bea3b581b839641)
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/config.h>
249 #include <linux/kernel.h>
250 #include <linux/errno.h>
251 #include <linux/init.h>
252 #include <linux/slab.h>
253 #include <linux/tty.h>
254 #include <linux/tty_driver.h>
255 #include <linux/tty_flip.h>
256 #include <linux/module.h>
257 #include <linux/spinlock.h>
258 #include <asm/uaccess.h>
259 #include <linux/usb.h>
260 #include <linux/serial.h>
261 #include "usb-serial.h"
262 #include "ftdi_sio.h"
263 
264 /*
265  * Version Information
266  */
267 #define DRIVER_VERSION "v1.4.3"
268 #define DRIVER_AUTHOR "Greg Kroah-Hartman <greg@kroah.com>, Bill Ryder <bryder@sgi.com>, Kuba Ober <kuba@mareimbrium.org>"
269 #define DRIVER_DESC "USB FTDI Serial Converters Driver"
270 
271 static int debug;
272 static __u16 vendor = FTDI_VID;
273 static __u16 product;
274 
275 /* struct ftdi_sio_quirk is used by devices requiring special attention. */
276 struct ftdi_sio_quirk {
277 	void (*setup)(struct usb_serial *); /* Special settings during startup. */
278 };
279 
280 static void  ftdi_USB_UIRT_setup	(struct usb_serial *serial);
281 static void  ftdi_HE_TIRA1_setup	(struct usb_serial *serial);
282 
283 static struct ftdi_sio_quirk ftdi_USB_UIRT_quirk = {
284 	.setup = ftdi_USB_UIRT_setup,
285 };
286 
287 static struct ftdi_sio_quirk ftdi_HE_TIRA1_quirk = {
288 	.setup = ftdi_HE_TIRA1_setup,
289 };
290 
291 /*
292  * The 8U232AM has the same API as the sio except for:
293  * - it can support MUCH higher baudrates; up to:
294  *   o 921600 for RS232 and 2000000 for RS422/485 at 48MHz
295  *   o 230400 at 12MHz
296  *   so .. 8U232AM's baudrate setting codes are different
297  * - it has a two byte status code.
298  * - it returns characters every 16ms (the FTDI does it every 40ms)
299  *
300  * the bcdDevice value is used to differentiate FT232BM and FT245BM from
301  * the earlier FT8U232AM and FT8U232BM.  For now, include all known VID/PID
302  * combinations in both tables.
303  * FIXME: perhaps bcdDevice can also identify 12MHz FT8U232AM devices,
304  * but I don't know if those ever went into mass production. [Ian Abbott]
305  */
306 
307 
308 
309 static struct usb_device_id id_table_combined [] = {
310 	{ USB_DEVICE(FTDI_VID, FTDI_IRTRANS_PID) },
311 	{ USB_DEVICE(FTDI_VID, FTDI_SIO_PID) },
312 	{ USB_DEVICE(FTDI_VID, FTDI_8U232AM_PID) },
313 	{ USB_DEVICE(FTDI_VID, FTDI_8U232AM_ALT_PID) },
314 	{ USB_DEVICE(FTDI_VID, FTDI_8U2232C_PID) },
315 	{ USB_DEVICE(FTDI_VID, FTDI_RELAIS_PID) },
316 	{ USB_DEVICE(INTERBIOMETRICS_VID, INTERBIOMETRICS_IOBOARD_PID) },
317 	{ USB_DEVICE(INTERBIOMETRICS_VID, INTERBIOMETRICS_MINI_IOBOARD_PID) },
318 	{ USB_DEVICE(FTDI_VID, FTDI_XF_632_PID) },
319 	{ USB_DEVICE(FTDI_VID, FTDI_XF_634_PID) },
320 	{ USB_DEVICE(FTDI_VID, FTDI_XF_547_PID) },
321 	{ USB_DEVICE(FTDI_VID, FTDI_XF_633_PID) },
322 	{ USB_DEVICE(FTDI_VID, FTDI_XF_631_PID) },
323 	{ USB_DEVICE(FTDI_VID, FTDI_XF_635_PID) },
324 	{ USB_DEVICE(FTDI_VID, FTDI_XF_640_PID) },
325 	{ USB_DEVICE(FTDI_VID, FTDI_XF_642_PID) },
326 	{ USB_DEVICE(FTDI_VID, FTDI_DSS20_PID) },
327 	{ USB_DEVICE(FTDI_NF_RIC_VID, FTDI_NF_RIC_PID) },
328 	{ USB_DEVICE(FTDI_VID, FTDI_VNHCPCUSB_D_PID) },
329 	{ USB_DEVICE(FTDI_VID, FTDI_MTXORB_0_PID) },
330 	{ USB_DEVICE(FTDI_VID, FTDI_MTXORB_1_PID) },
331 	{ USB_DEVICE(FTDI_VID, FTDI_MTXORB_2_PID) },
332 	{ USB_DEVICE(FTDI_VID, FTDI_MTXORB_3_PID) },
333 	{ USB_DEVICE(FTDI_VID, FTDI_MTXORB_4_PID) },
334 	{ USB_DEVICE(FTDI_VID, FTDI_MTXORB_5_PID) },
335 	{ USB_DEVICE(FTDI_VID, FTDI_MTXORB_6_PID) },
336 	{ USB_DEVICE(FTDI_VID, FTDI_PERLE_ULTRAPORT_PID) },
337 	{ USB_DEVICE(FTDI_VID, FTDI_PIEGROUP_PID) },
338 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2101_PID) },
339 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2102_PID) },
340 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2103_PID) },
341 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2104_PID) },
342 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2201_1_PID) },
343 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2201_2_PID) },
344 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2202_1_PID) },
345 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2202_2_PID) },
346 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2203_1_PID) },
347 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2203_2_PID) },
348 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2401_1_PID) },
349 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2401_2_PID) },
350 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2401_3_PID) },
351 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2401_4_PID) },
352 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2402_1_PID) },
353 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2402_2_PID) },
354 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2402_3_PID) },
355 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2402_4_PID) },
356 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2403_1_PID) },
357 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2403_2_PID) },
358 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2403_3_PID) },
359 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2403_4_PID) },
360 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2801_1_PID) },
361 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2801_2_PID) },
362 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2801_3_PID) },
363 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2801_4_PID) },
364 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2801_5_PID) },
365 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2801_6_PID) },
366 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2801_7_PID) },
367 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2801_8_PID) },
368 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2802_1_PID) },
369 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2802_2_PID) },
370 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2802_3_PID) },
371 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2802_4_PID) },
372 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2802_5_PID) },
373 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2802_6_PID) },
374 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2802_7_PID) },
375 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2802_8_PID) },
376 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2803_1_PID) },
377 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2803_2_PID) },
378 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2803_3_PID) },
379 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2803_4_PID) },
380 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2803_5_PID) },
381 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2803_6_PID) },
382 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2803_7_PID) },
383 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2803_8_PID) },
384 	{ USB_DEVICE(IDTECH_VID, IDTECH_IDT1221U_PID) },
385 	{ USB_DEVICE(OCT_VID, OCT_US101_PID) },
386 	{ USB_DEVICE(FTDI_VID, FTDI_HE_TIRA1_PID),
387 		.driver_info = (kernel_ulong_t)&ftdi_HE_TIRA1_quirk },
388 	{ USB_DEVICE(FTDI_VID, FTDI_USB_UIRT_PID),
389 		.driver_info = (kernel_ulong_t)&ftdi_USB_UIRT_quirk },
390 	{ USB_DEVICE(FTDI_VID, PROTEGO_SPECIAL_1) },
391 	{ USB_DEVICE(FTDI_VID, PROTEGO_R2X0) },
392 	{ USB_DEVICE(FTDI_VID, PROTEGO_SPECIAL_3) },
393 	{ USB_DEVICE(FTDI_VID, PROTEGO_SPECIAL_4) },
394 	{ USB_DEVICE(FTDI_VID, FTDI_GUDEADS_E808_PID) },
395 	{ USB_DEVICE(FTDI_VID, FTDI_GUDEADS_E809_PID) },
396 	{ USB_DEVICE(FTDI_VID, FTDI_GUDEADS_E80A_PID) },
397 	{ USB_DEVICE(FTDI_VID, FTDI_GUDEADS_E80B_PID) },
398 	{ USB_DEVICE(FTDI_VID, FTDI_GUDEADS_E80C_PID) },
399 	{ USB_DEVICE(FTDI_VID, FTDI_GUDEADS_E80D_PID) },
400 	{ USB_DEVICE(FTDI_VID, FTDI_GUDEADS_E80E_PID) },
401 	{ USB_DEVICE(FTDI_VID, FTDI_GUDEADS_E80F_PID) },
402 	{ USB_DEVICE(FTDI_VID, FTDI_GUDEADS_E888_PID) },
403 	{ USB_DEVICE(FTDI_VID, FTDI_GUDEADS_E889_PID) },
404 	{ USB_DEVICE(FTDI_VID, FTDI_GUDEADS_E88A_PID) },
405 	{ USB_DEVICE(FTDI_VID, FTDI_GUDEADS_E88B_PID) },
406 	{ USB_DEVICE(FTDI_VID, FTDI_GUDEADS_E88C_PID) },
407 	{ USB_DEVICE(FTDI_VID, FTDI_GUDEADS_E88D_PID) },
408 	{ USB_DEVICE(FTDI_VID, FTDI_GUDEADS_E88E_PID) },
409 	{ USB_DEVICE(FTDI_VID, FTDI_GUDEADS_E88F_PID) },
410 	{ USB_DEVICE(FTDI_VID, FTDI_ELV_UO100_PID) },
411 	{ USB_DEVICE(FTDI_VID, FTDI_ELV_UM100_PID) },
412 	{ USB_DEVICE(FTDI_VID, FTDI_ELV_UR100_PID) },
413 	{ USB_DEVICE(FTDI_VID, FTDI_ELV_ALC8500_PID) },
414 	{ USB_DEVICE(FTDI_VID, FTDI_PYRAMID_PID) },
415 	{ USB_DEVICE(FTDI_VID, FTDI_ELV_FHZ1000PC_PID) },
416 	/*
417 	 * These will probably use user-space drivers.  Uncomment them if
418 	 * you need them or use the user-specified vendor/product module
419 	 * parameters (see ftdi_sio.h for the numbers).  Make a fuss if
420 	 * you think the driver should recognize any of them by default.
421 	 */
422 	/* { USB_DEVICE(FTDI_VID, FTDI_ELV_CLI7000_PID) }, */
423 	/* { USB_DEVICE(FTDI_VID, FTDI_ELV_PPS7330_PID) }, */
424 	/* { USB_DEVICE(FTDI_VID, FTDI_ELV_TFM100_PID) }, */
425 	/* { USB_DEVICE(FTDI_VID, FTDI_ELV_UDF77_PID) }, */
426 	/* { USB_DEVICE(FTDI_VID, FTDI_ELV_UIO88_PID) }, */
427 	/* { USB_DEVICE(FTDI_VID, FTDI_ELV_UAD8_PID) }, */
428 	/* { USB_DEVICE(FTDI_VID, FTDI_ELV_UDA7_PID) }, */
429 	/* { USB_DEVICE(FTDI_VID, FTDI_ELV_USI2_PID) }, */
430 	/* { USB_DEVICE(FTDI_VID, FTDI_ELV_T1100_PID) }, */
431 	/* { USB_DEVICE(FTDI_VID, FTDI_ELV_PCD200_PID) }, */
432 	/* { USB_DEVICE(FTDI_VID, FTDI_ELV_ULA200_PID) }, */
433 	/* { USB_DEVICE(FTDI_VID, FTDI_ELV_CSI8_PID) }, */
434 	/* { USB_DEVICE(FTDI_VID, FTDI_ELV_EM1000DL_PID) }, */
435 	/* { USB_DEVICE(FTDI_VID, FTDI_ELV_PCK100_PID) }, */
436 	/* { USB_DEVICE(FTDI_VID, FTDI_ELV_RFP500_PID) }, */
437 	/* { USB_DEVICE(FTDI_VID, FTDI_ELV_FS20SIG_PID) }, */
438 	/* { USB_DEVICE(FTDI_VID, FTDI_ELV_WS300PC_PID) }, */
439 	/* { USB_DEVICE(FTDI_VID, FTDI_ELV_FHZ1300PC_PID) }, */
440 	/* { USB_DEVICE(FTDI_VID, FTDI_ELV_WS500_PID) }, */
441  	{ USB_DEVICE(FTDI_VID, LINX_SDMUSBQSS_PID) },
442  	{ USB_DEVICE(FTDI_VID, LINX_MASTERDEVEL2_PID) },
443  	{ USB_DEVICE(FTDI_VID, LINX_FUTURE_0_PID) },
444  	{ USB_DEVICE(FTDI_VID, LINX_FUTURE_1_PID) },
445  	{ USB_DEVICE(FTDI_VID, LINX_FUTURE_2_PID) },
446  	{ USB_DEVICE(FTDI_VID, FTDI_CCSICDU20_0_PID) },
447  	{ USB_DEVICE(FTDI_VID, FTDI_CCSICDU40_1_PID) },
448 	{ USB_DEVICE(FTDI_VID, INSIDE_ACCESSO) },
449 	{ USB_DEVICE(INTREPID_VID, INTREPID_VALUECAN_PID) },
450 	{ USB_DEVICE(INTREPID_VID, INTREPID_NEOVI_PID) },
451 	{ USB_DEVICE(FALCOM_VID, FALCOM_TWIST_PID) },
452 	{ USB_DEVICE(FALCOM_VID, FALCOM_SAMBA_PID) },
453 	{ USB_DEVICE(FTDI_VID, FTDI_SUUNTO_SPORTS_PID) },
454 	{ USB_DEVICE(FTDI_VID, FTDI_RM_CANVIEW_PID) },
455 	{ USB_DEVICE(BANDB_VID, BANDB_USOTL4_PID) },
456 	{ USB_DEVICE(BANDB_VID, BANDB_USTL4_PID) },
457 	{ USB_DEVICE(BANDB_VID, BANDB_USO9ML2_PID) },
458 	{ USB_DEVICE(FTDI_VID, EVER_ECO_PRO_CDS) },
459 	{ USB_DEVICE(FTDI_VID, FTDI_4N_GALAXY_DE_0_PID) },
460 	{ USB_DEVICE(FTDI_VID, FTDI_4N_GALAXY_DE_1_PID) },
461 	{ USB_DEVICE(FTDI_VID, FTDI_4N_GALAXY_DE_2_PID) },
462 	{ USB_DEVICE(FTDI_VID, XSENS_CONVERTER_0_PID) },
463 	{ USB_DEVICE(FTDI_VID, XSENS_CONVERTER_1_PID) },
464 	{ USB_DEVICE(FTDI_VID, XSENS_CONVERTER_2_PID) },
465 	{ USB_DEVICE(FTDI_VID, XSENS_CONVERTER_3_PID) },
466 	{ USB_DEVICE(FTDI_VID, XSENS_CONVERTER_4_PID) },
467 	{ USB_DEVICE(FTDI_VID, XSENS_CONVERTER_5_PID) },
468 	{ USB_DEVICE(FTDI_VID, XSENS_CONVERTER_6_PID) },
469 	{ USB_DEVICE(FTDI_VID, XSENS_CONVERTER_7_PID) },
470 	{ USB_DEVICE(MOBILITY_VID, MOBILITY_USB_SERIAL_PID) },
471 	{ USB_DEVICE(FTDI_VID, FTDI_ACTIVE_ROBOTS_PID) },
472 	{ USB_DEVICE(FTDI_VID, FTDI_MHAM_Y6_PID) },
473 	{ USB_DEVICE(FTDI_VID, FTDI_MHAM_Y8_PID) },
474 	{ USB_DEVICE(EVOLUTION_VID, EVOLUTION_ER1_PID) },
475 	{ USB_DEVICE(FTDI_VID, FTDI_ARTEMIS_PID) },
476 	{ USB_DEVICE(FTDI_VID, FTDI_ATIK_ATK16_PID) },
477 	{ USB_DEVICE(FTDI_VID, FTDI_ATIK_ATK16HR_PID) },
478 	{ USB_DEVICE(KOBIL_VID, KOBIL_CONV_B1_PID) },
479 	{ USB_DEVICE(KOBIL_VID, KOBIL_CONV_KAAN_PID) },
480 	{ },					/* Optional parameter entry */
481 	{ }					/* Terminating entry */
482 };
483 
484 MODULE_DEVICE_TABLE (usb, id_table_combined);
485 
486 static struct usb_driver ftdi_driver = {
487 	.name =		"ftdi_sio",
488 	.probe =	usb_serial_probe,
489 	.disconnect =	usb_serial_disconnect,
490 	.id_table =	id_table_combined,
491 };
492 
493 static char *ftdi_chip_name[] = {
494 	[SIO] = "SIO",	/* the serial part of FT8U100AX */
495 	[FT8U232AM] = "FT8U232AM",
496 	[FT232BM] = "FT232BM",
497 	[FT2232C] = "FT2232C",
498 };
499 
500 
501 /* Constants for read urb and write urb */
502 #define BUFSZ 512
503 #define PKTSZ 64
504 
505 /* rx_flags */
506 #define THROTTLED		0x01
507 #define ACTUALLY_THROTTLED	0x02
508 
509 struct ftdi_private {
510 	ftdi_chip_type_t chip_type;
511 				/* type of the device, either SIO or FT8U232AM */
512 	int baud_base;		/* baud base clock for divisor setting */
513 	int custom_divisor;	/* custom_divisor kludge, this is for baud_base (different from what goes to the chip!) */
514 	__u16 last_set_data_urb_value ;
515 				/* the last data state set - needed for doing a break */
516         int write_offset;       /* This is the offset in the usb data block to write the serial data -
517 				 * it is different between devices
518 				 */
519 	int flags;		/* some ASYNC_xxxx flags are supported */
520 	unsigned long last_dtr_rts;	/* saved modem control outputs */
521         wait_queue_head_t delta_msr_wait; /* Used for TIOCMIWAIT */
522  	char prev_status, diff_status;        /* Used for TIOCMIWAIT */
523 	__u8 rx_flags;		/* receive state flags (throttling) */
524 	spinlock_t rx_lock;	/* spinlock for receive state */
525 	struct work_struct rx_work;
526 	int rx_processed;
527 
528 	__u16 interface;	/* FT2232C port interface (0 for FT232/245) */
529 
530 	int force_baud;		/* if non-zero, force the baud rate to this value */
531 	int force_rtscts;	/* if non-zero, force RTS-CTS to always be enabled */
532 };
533 
534 /* Used for TIOCMIWAIT */
535 #define FTDI_STATUS_B0_MASK	(FTDI_RS0_CTS | FTDI_RS0_DSR | FTDI_RS0_RI | FTDI_RS0_RLSD)
536 #define FTDI_STATUS_B1_MASK	(FTDI_RS_BI)
537 /* End TIOCMIWAIT */
538 
539 #define FTDI_IMPL_ASYNC_FLAGS = ( ASYNC_SPD_HI | ASYNC_SPD_VHI \
540  ASYNC_SPD_CUST | ASYNC_SPD_SHI | ASYNC_SPD_WARP )
541 
542 /* function prototypes for a FTDI serial converter */
543 static int  ftdi_sio_probe	(struct usb_serial *serial, const struct usb_device_id *id);
544 static int  ftdi_sio_attach		(struct usb_serial *serial);
545 static void ftdi_shutdown		(struct usb_serial *serial);
546 static int  ftdi_open			(struct usb_serial_port *port, struct file *filp);
547 static void ftdi_close			(struct usb_serial_port *port, struct file *filp);
548 static int  ftdi_write			(struct usb_serial_port *port, const unsigned char *buf, int count);
549 static int  ftdi_write_room		(struct usb_serial_port *port);
550 static int  ftdi_chars_in_buffer	(struct usb_serial_port *port);
551 static void ftdi_write_bulk_callback	(struct urb *urb, struct pt_regs *regs);
552 static void ftdi_read_bulk_callback	(struct urb *urb, struct pt_regs *regs);
553 static void ftdi_process_read		(void *param);
554 static void ftdi_set_termios		(struct usb_serial_port *port, struct termios * old);
555 static int  ftdi_tiocmget               (struct usb_serial_port *port, struct file *file);
556 static int  ftdi_tiocmset		(struct usb_serial_port *port, struct file * file, unsigned int set, unsigned int clear);
557 static int  ftdi_ioctl			(struct usb_serial_port *port, struct file * file, unsigned int cmd, unsigned long arg);
558 static void ftdi_break_ctl		(struct usb_serial_port *port, int break_state );
559 static void ftdi_throttle		(struct usb_serial_port *port);
560 static void ftdi_unthrottle		(struct usb_serial_port *port);
561 
562 static unsigned short int ftdi_232am_baud_base_to_divisor (int baud, int base);
563 static unsigned short int ftdi_232am_baud_to_divisor (int baud);
564 static __u32 ftdi_232bm_baud_base_to_divisor (int baud, int base);
565 static __u32 ftdi_232bm_baud_to_divisor (int baud);
566 
567 static struct usb_serial_driver ftdi_sio_device = {
568 	.driver = {
569 		.owner =	THIS_MODULE,
570 		.name =		"ftdi_sio",
571 	},
572 	.description =		"FTDI USB Serial Device",
573 	.id_table =		id_table_combined,
574 	.num_interrupt_in =	0,
575 	.num_bulk_in =		1,
576 	.num_bulk_out =		1,
577 	.num_ports =		1,
578 	.probe =		ftdi_sio_probe,
579 	.open =			ftdi_open,
580 	.close =		ftdi_close,
581 	.throttle =		ftdi_throttle,
582 	.unthrottle =		ftdi_unthrottle,
583 	.write =		ftdi_write,
584 	.write_room =		ftdi_write_room,
585 	.chars_in_buffer =	ftdi_chars_in_buffer,
586 	.read_bulk_callback =	ftdi_read_bulk_callback,
587 	.write_bulk_callback =	ftdi_write_bulk_callback,
588 	.tiocmget =             ftdi_tiocmget,
589 	.tiocmset =             ftdi_tiocmset,
590 	.ioctl =		ftdi_ioctl,
591 	.set_termios =		ftdi_set_termios,
592 	.break_ctl =		ftdi_break_ctl,
593 	.attach =		ftdi_sio_attach,
594 	.shutdown =		ftdi_shutdown,
595 };
596 
597 
598 #define WDR_TIMEOUT 5000 /* default urb timeout */
599 #define WDR_SHORT_TIMEOUT 1000	/* shorter urb timeout */
600 
601 /* High and low are for DTR, RTS etc etc */
602 #define HIGH 1
603 #define LOW 0
604 
605 /*
606  * ***************************************************************************
607  * Utlity functions
608  * ***************************************************************************
609  */
610 
611 static unsigned short int ftdi_232am_baud_base_to_divisor(int baud, int base)
612 {
613 	unsigned short int divisor;
614 	int divisor3 = base / 2 / baud; // divisor shifted 3 bits to the left
615 	if ((divisor3 & 0x7) == 7) divisor3 ++; // round x.7/8 up to x+1
616 	divisor = divisor3 >> 3;
617 	divisor3 &= 0x7;
618 	if (divisor3 == 1) divisor |= 0xc000; else // 0.125
619 	if (divisor3 >= 4) divisor |= 0x4000; else // 0.5
620 	if (divisor3 != 0) divisor |= 0x8000;      // 0.25
621 	if (divisor == 1) divisor = 0;	/* special case for maximum baud rate */
622 	return divisor;
623 }
624 
625 static unsigned short int ftdi_232am_baud_to_divisor(int baud)
626 {
627 	 return(ftdi_232am_baud_base_to_divisor(baud, 48000000));
628 }
629 
630 static __u32 ftdi_232bm_baud_base_to_divisor(int baud, int base)
631 {
632 	static const unsigned char divfrac[8] = { 0, 3, 2, 4, 1, 5, 6, 7 };
633 	__u32 divisor;
634 	int divisor3 = base / 2 / baud; // divisor shifted 3 bits to the left
635 	divisor = divisor3 >> 3;
636 	divisor |= (__u32)divfrac[divisor3 & 0x7] << 14;
637 	/* Deal with special cases for highest baud rates. */
638 	if (divisor == 1) divisor = 0; else	// 1.0
639 	if (divisor == 0x4001) divisor = 1;	// 1.5
640 	return divisor;
641 }
642 
643 static __u32 ftdi_232bm_baud_to_divisor(int baud)
644 {
645 	 return(ftdi_232bm_baud_base_to_divisor(baud, 48000000));
646 }
647 
648 #define set_mctrl(port, set)		update_mctrl((port), (set), 0)
649 #define clear_mctrl(port, clear)	update_mctrl((port), 0, (clear))
650 
651 static int update_mctrl(struct usb_serial_port *port, unsigned int set, unsigned int clear)
652 {
653 	struct ftdi_private *priv = usb_get_serial_port_data(port);
654 	char *buf;
655 	unsigned urb_value;
656 	int rv;
657 
658 	if (((set | clear) & (TIOCM_DTR | TIOCM_RTS)) == 0) {
659 		dbg("%s - DTR|RTS not being set|cleared", __FUNCTION__);
660 		return 0;	/* no change */
661 	}
662 
663 	buf = kmalloc(1, GFP_NOIO);
664 	if (!buf) {
665 		return -ENOMEM;
666 	}
667 
668 	clear &= ~set;	/* 'set' takes precedence over 'clear' */
669 	urb_value = 0;
670 	if (clear & TIOCM_DTR)
671 		urb_value |= FTDI_SIO_SET_DTR_LOW;
672 	if (clear & TIOCM_RTS)
673 		urb_value |= FTDI_SIO_SET_RTS_LOW;
674 	if (set & TIOCM_DTR)
675 		urb_value |= FTDI_SIO_SET_DTR_HIGH;
676 	if (set & TIOCM_RTS)
677 		urb_value |= FTDI_SIO_SET_RTS_HIGH;
678 	rv = usb_control_msg(port->serial->dev,
679 			       usb_sndctrlpipe(port->serial->dev, 0),
680 			       FTDI_SIO_SET_MODEM_CTRL_REQUEST,
681 			       FTDI_SIO_SET_MODEM_CTRL_REQUEST_TYPE,
682 			       urb_value, priv->interface,
683 			       buf, 0, WDR_TIMEOUT);
684 
685 	kfree(buf);
686 	if (rv < 0) {
687 		err("%s Error from MODEM_CTRL urb: DTR %s, RTS %s",
688 				__FUNCTION__,
689 				(set & TIOCM_DTR) ? "HIGH" :
690 				(clear & TIOCM_DTR) ? "LOW" : "unchanged",
691 				(set & TIOCM_RTS) ? "HIGH" :
692 				(clear & TIOCM_RTS) ? "LOW" : "unchanged");
693 	} else {
694 		dbg("%s - DTR %s, RTS %s", __FUNCTION__,
695 				(set & TIOCM_DTR) ? "HIGH" :
696 				(clear & TIOCM_DTR) ? "LOW" : "unchanged",
697 				(set & TIOCM_RTS) ? "HIGH" :
698 				(clear & TIOCM_RTS) ? "LOW" : "unchanged");
699 		priv->last_dtr_rts = (priv->last_dtr_rts & ~clear) | set;
700 	}
701 	return rv;
702 }
703 
704 
705 static __u32 get_ftdi_divisor(struct usb_serial_port * port);
706 
707 
708 static int change_speed(struct usb_serial_port *port)
709 {
710 	struct ftdi_private *priv = usb_get_serial_port_data(port);
711 	char *buf;
712         __u16 urb_value;
713 	__u16 urb_index;
714 	__u32 urb_index_value;
715 	int rv;
716 
717 	buf = kmalloc(1, GFP_NOIO);
718 	if (!buf)
719 		return -ENOMEM;
720 
721 	urb_index_value = get_ftdi_divisor(port);
722 	urb_value = (__u16)urb_index_value;
723 	urb_index = (__u16)(urb_index_value >> 16);
724 	if (priv->interface) {	/* FT2232C */
725 		urb_index = (__u16)((urb_index << 8) | priv->interface);
726 	}
727 
728 	rv = usb_control_msg(port->serial->dev,
729 			    usb_sndctrlpipe(port->serial->dev, 0),
730 			    FTDI_SIO_SET_BAUDRATE_REQUEST,
731 			    FTDI_SIO_SET_BAUDRATE_REQUEST_TYPE,
732 			    urb_value, urb_index,
733 			    buf, 0, WDR_SHORT_TIMEOUT);
734 
735 	kfree(buf);
736 	return rv;
737 }
738 
739 
740 static __u32 get_ftdi_divisor(struct usb_serial_port * port)
741 { /* get_ftdi_divisor */
742 	struct ftdi_private *priv = usb_get_serial_port_data(port);
743 	__u32 div_value = 0;
744 	int div_okay = 1;
745 	int baud;
746 
747 	/*
748 	 * The logic involved in setting the baudrate can be cleanly split in 3 steps.
749 	 * Obtaining the actual baud rate is a little tricky since unix traditionally
750 	 * somehow ignored the possibility to set non-standard baud rates.
751 	 * 1. Standard baud rates are set in tty->termios->c_cflag
752 	 * 2. If these are not enough, you can set any speed using alt_speed as follows:
753 	 *    - set tty->termios->c_cflag speed to B38400
754 	 *    - set your real speed in tty->alt_speed; it gets ignored when
755 	 *      alt_speed==0, (or)
756 	 *    - call TIOCSSERIAL ioctl with (struct serial_struct) set as follows:
757 	 *      flags & ASYNC_SPD_MASK == ASYNC_SPD_[HI, VHI, SHI, WARP], this just
758 	 *      sets alt_speed to (HI: 57600, VHI: 115200, SHI: 230400, WARP: 460800)
759 	 * ** Steps 1, 2 are done courtesy of tty_get_baud_rate
760 	 * 3. You can also set baud rate by setting custom divisor as follows
761 	 *    - set tty->termios->c_cflag speed to B38400
762 	 *    - call TIOCSSERIAL ioctl with (struct serial_struct) set as follows:
763 	 *      o flags & ASYNC_SPD_MASK == ASYNC_SPD_CUST
764 	 *      o custom_divisor set to baud_base / your_new_baudrate
765 	 * ** Step 3 is done courtesy of code borrowed from serial.c - I should really
766 	 *    spend some time and separate+move this common code to serial.c, it is
767 	 *    replicated in nearly every serial driver you see.
768 	 */
769 
770 	/* 1. Get the baud rate from the tty settings, this observes alt_speed hack */
771 
772 	baud = tty_get_baud_rate(port->tty);
773 	dbg("%s - tty_get_baud_rate reports speed %d", __FUNCTION__, baud);
774 
775 	/* 2. Observe async-compatible custom_divisor hack, update baudrate if needed */
776 
777 	if (baud == 38400 &&
778 	    ((priv->flags & ASYNC_SPD_MASK) == ASYNC_SPD_CUST) &&
779 	     (priv->custom_divisor)) {
780 		baud = priv->baud_base / priv->custom_divisor;
781 		dbg("%s - custom divisor %d sets baud rate to %d", __FUNCTION__, priv->custom_divisor, baud);
782 	}
783 
784 	/* 3. Convert baudrate to device-specific divisor */
785 
786 	if (!baud) baud = 9600;
787 	switch(priv->chip_type) {
788 	case SIO: /* SIO chip */
789 		switch(baud) {
790 		case 300: div_value = ftdi_sio_b300; break;
791 		case 600: div_value = ftdi_sio_b600; break;
792 		case 1200: div_value = ftdi_sio_b1200; break;
793 		case 2400: div_value = ftdi_sio_b2400; break;
794 		case 4800: div_value = ftdi_sio_b4800; break;
795 		case 9600: div_value = ftdi_sio_b9600; break;
796 		case 19200: div_value = ftdi_sio_b19200; break;
797 		case 38400: div_value = ftdi_sio_b38400; break;
798 		case 57600: div_value = ftdi_sio_b57600;  break;
799 		case 115200: div_value = ftdi_sio_b115200; break;
800 		} /* baud */
801 		if (div_value == 0) {
802   			dbg("%s - Baudrate (%d) requested is not supported", __FUNCTION__,  baud);
803 			div_value = ftdi_sio_b9600;
804 			div_okay = 0;
805 		}
806 		break;
807 	case FT8U232AM: /* 8U232AM chip */
808 		if (baud <= 3000000) {
809 			div_value = ftdi_232am_baud_to_divisor(baud);
810 		} else {
811 	                dbg("%s - Baud rate too high!", __FUNCTION__);
812 			div_value = ftdi_232am_baud_to_divisor(9600);
813 			div_okay = 0;
814 		}
815 		break;
816 	case FT232BM: /* FT232BM chip */
817 	case FT2232C: /* FT2232C chip */
818 		if (baud <= 3000000) {
819 			div_value = ftdi_232bm_baud_to_divisor(baud);
820 		} else {
821 	                dbg("%s - Baud rate too high!", __FUNCTION__);
822 			div_value = ftdi_232bm_baud_to_divisor(9600);
823 			div_okay = 0;
824 		}
825 		break;
826 	} /* priv->chip_type */
827 
828 	if (div_okay) {
829 		dbg("%s - Baud rate set to %d (divisor 0x%lX) on chip %s",
830 			__FUNCTION__, baud, (unsigned long)div_value,
831 			ftdi_chip_name[priv->chip_type]);
832 	}
833 
834 	return(div_value);
835 }
836 
837 
838 static int get_serial_info(struct usb_serial_port * port, struct serial_struct __user * retinfo)
839 {
840 	struct ftdi_private *priv = usb_get_serial_port_data(port);
841 	struct serial_struct tmp;
842 
843 	if (!retinfo)
844 		return -EFAULT;
845 	memset(&tmp, 0, sizeof(tmp));
846 	tmp.flags = priv->flags;
847 	tmp.baud_base = priv->baud_base;
848 	tmp.custom_divisor = priv->custom_divisor;
849 	if (copy_to_user(retinfo, &tmp, sizeof(*retinfo)))
850 		return -EFAULT;
851 	return 0;
852 } /* get_serial_info */
853 
854 
855 static int set_serial_info(struct usb_serial_port * port, struct serial_struct __user * newinfo)
856 { /* set_serial_info */
857 	struct ftdi_private *priv = usb_get_serial_port_data(port);
858 	struct serial_struct new_serial;
859 	struct ftdi_private old_priv;
860 
861 	if (copy_from_user(&new_serial, newinfo, sizeof(new_serial)))
862 		return -EFAULT;
863 	old_priv = * priv;
864 
865 	/* Do error checking and permission checking */
866 
867 	if (!capable(CAP_SYS_ADMIN)) {
868 		if (((new_serial.flags & ~ASYNC_USR_MASK) !=
869 		     (priv->flags & ~ASYNC_USR_MASK)))
870 			return -EPERM;
871 		priv->flags = ((priv->flags & ~ASYNC_USR_MASK) |
872 			       (new_serial.flags & ASYNC_USR_MASK));
873 		priv->custom_divisor = new_serial.custom_divisor;
874 		goto check_and_exit;
875 	}
876 
877 	if ((new_serial.baud_base != priv->baud_base) &&
878 	    (new_serial.baud_base < 9600))
879 		return -EINVAL;
880 
881 	/* Make the changes - these are privileged changes! */
882 
883 	priv->flags = ((priv->flags & ~ASYNC_FLAGS) |
884 	               (new_serial.flags & ASYNC_FLAGS));
885 	priv->custom_divisor = new_serial.custom_divisor;
886 
887 	port->tty->low_latency = (priv->flags & ASYNC_LOW_LATENCY) ? 1 : 0;
888 
889 check_and_exit:
890 	if ((old_priv.flags & ASYNC_SPD_MASK) !=
891 	     (priv->flags & ASYNC_SPD_MASK)) {
892 		if ((priv->flags & ASYNC_SPD_MASK) == ASYNC_SPD_HI)
893 			port->tty->alt_speed = 57600;
894 		else if ((priv->flags & ASYNC_SPD_MASK) == ASYNC_SPD_VHI)
895 			port->tty->alt_speed = 115200;
896 		else if ((priv->flags & ASYNC_SPD_MASK) == ASYNC_SPD_SHI)
897 			port->tty->alt_speed = 230400;
898 		else if ((priv->flags & ASYNC_SPD_MASK) == ASYNC_SPD_WARP)
899 			port->tty->alt_speed = 460800;
900 		else
901 			port->tty->alt_speed = 0;
902 	}
903 	if (((old_priv.flags & ASYNC_SPD_MASK) !=
904 	     (priv->flags & ASYNC_SPD_MASK)) ||
905 	    (((priv->flags & ASYNC_SPD_MASK) == ASYNC_SPD_CUST) &&
906 	     (old_priv.custom_divisor != priv->custom_divisor))) {
907 		change_speed(port);
908 	}
909 
910 	return (0);
911 
912 } /* set_serial_info */
913 
914 
915 /* Determine type of FTDI chip based on USB config and descriptor. */
916 static void ftdi_determine_type(struct usb_serial_port *port)
917 {
918 	struct ftdi_private *priv = usb_get_serial_port_data(port);
919 	struct usb_serial *serial = port->serial;
920 	struct usb_device *udev = serial->dev;
921 	unsigned version;
922 	unsigned interfaces;
923 
924 	/* Assume it is not the original SIO device for now. */
925 	priv->baud_base = 48000000 / 2;
926 	priv->write_offset = 0;
927 
928 	version = le16_to_cpu(udev->descriptor.bcdDevice);
929 	interfaces = udev->actconfig->desc.bNumInterfaces;
930 	dbg("%s: bcdDevice = 0x%x, bNumInterfaces = %u", __FUNCTION__,
931 			version, interfaces);
932 	if (interfaces > 1) {
933 		int inter;
934 
935 		/* Multiple interfaces.  Assume FT2232C. */
936 		priv->chip_type = FT2232C;
937 		/* Determine interface code. */
938 		inter = serial->interface->altsetting->desc.bInterfaceNumber;
939 		if (inter == 0) {
940 			priv->interface = PIT_SIOA;
941 		} else {
942 			priv->interface = PIT_SIOB;
943 		}
944 		/* BM-type devices have a bug where bcdDevice gets set
945 		 * to 0x200 when iSerialNumber is 0.  */
946 		if (version < 0x500) {
947 			dbg("%s: something fishy - bcdDevice too low for multi-interface device",
948 					__FUNCTION__);
949 		}
950 	} else if (version < 0x200) {
951 		/* Old device.  Assume its the original SIO. */
952 		priv->chip_type = SIO;
953 		priv->baud_base = 12000000 / 16;
954 		priv->write_offset = 1;
955 	} else if (version < 0x400) {
956 		/* Assume its an FT8U232AM (or FT8U245AM) */
957 		/* (It might be a BM because of the iSerialNumber bug,
958 		 * but it will still work as an AM device.) */
959 		priv->chip_type = FT8U232AM;
960 	} else {
961 		/* Assume its an FT232BM (or FT245BM) */
962 		priv->chip_type = FT232BM;
963 	}
964 	info("Detected %s", ftdi_chip_name[priv->chip_type]);
965 }
966 
967 
968 /*
969  * ***************************************************************************
970  * Sysfs Attribute
971  * ***************************************************************************
972  */
973 
974 static ssize_t show_latency_timer(struct device *dev, struct device_attribute *attr, char *buf)
975 {
976 	struct usb_serial_port *port = to_usb_serial_port(dev);
977 	struct ftdi_private *priv = usb_get_serial_port_data(port);
978 	struct usb_device *udev;
979 	unsigned short latency = 0;
980 	int rv = 0;
981 
982 	udev = to_usb_device(dev);
983 
984 	dbg("%s",__FUNCTION__);
985 
986 	rv = usb_control_msg(udev,
987 			     usb_rcvctrlpipe(udev, 0),
988 			     FTDI_SIO_GET_LATENCY_TIMER_REQUEST,
989 			     FTDI_SIO_GET_LATENCY_TIMER_REQUEST_TYPE,
990 			     0, priv->interface,
991 			     (char*) &latency, 1, WDR_TIMEOUT);
992 
993 	if (rv < 0) {
994 		dev_err(dev, "Unable to read latency timer: %i", rv);
995 		return -EIO;
996 	}
997 	return sprintf(buf, "%i\n", latency);
998 }
999 
1000 /* Write a new value of the latency timer, in units of milliseconds. */
1001 static ssize_t store_latency_timer(struct device *dev, struct device_attribute *attr, const char *valbuf,
1002 				   size_t count)
1003 {
1004 	struct usb_serial_port *port = to_usb_serial_port(dev);
1005 	struct ftdi_private *priv = usb_get_serial_port_data(port);
1006 	struct usb_device *udev;
1007 	char buf[1];
1008 	int v = simple_strtoul(valbuf, NULL, 10);
1009 	int rv = 0;
1010 
1011 	udev = to_usb_device(dev);
1012 
1013 	dbg("%s: setting latency timer = %i", __FUNCTION__, v);
1014 
1015 	rv = usb_control_msg(udev,
1016 			     usb_sndctrlpipe(udev, 0),
1017 			     FTDI_SIO_SET_LATENCY_TIMER_REQUEST,
1018 			     FTDI_SIO_SET_LATENCY_TIMER_REQUEST_TYPE,
1019 			     v, priv->interface,
1020 			     buf, 0, WDR_TIMEOUT);
1021 
1022 	if (rv < 0) {
1023 		dev_err(dev, "Unable to write latency timer: %i", rv);
1024 		return -EIO;
1025 	}
1026 
1027 	return count;
1028 }
1029 
1030 /* Write an event character directly to the FTDI register.  The ASCII
1031    value is in the low 8 bits, with the enable bit in the 9th bit. */
1032 static ssize_t store_event_char(struct device *dev, struct device_attribute *attr, const char *valbuf,
1033 				size_t count)
1034 {
1035 	struct usb_serial_port *port = to_usb_serial_port(dev);
1036 	struct ftdi_private *priv = usb_get_serial_port_data(port);
1037 	struct usb_device *udev;
1038 	char buf[1];
1039 	int v = simple_strtoul(valbuf, NULL, 10);
1040 	int rv = 0;
1041 
1042 	udev = to_usb_device(dev);
1043 
1044 	dbg("%s: setting event char = %i", __FUNCTION__, v);
1045 
1046 	rv = usb_control_msg(udev,
1047 			     usb_sndctrlpipe(udev, 0),
1048 			     FTDI_SIO_SET_EVENT_CHAR_REQUEST,
1049 			     FTDI_SIO_SET_EVENT_CHAR_REQUEST_TYPE,
1050 			     v, priv->interface,
1051 			     buf, 0, WDR_TIMEOUT);
1052 
1053 	if (rv < 0) {
1054 		dbg("Unable to write event character: %i", rv);
1055 		return -EIO;
1056 	}
1057 
1058 	return count;
1059 }
1060 
1061 static DEVICE_ATTR(latency_timer, S_IWUSR | S_IRUGO, show_latency_timer, store_latency_timer);
1062 static DEVICE_ATTR(event_char, S_IWUSR, NULL, store_event_char);
1063 
1064 static void create_sysfs_attrs(struct usb_serial *serial)
1065 {
1066 	struct ftdi_private *priv;
1067 	struct usb_device *udev;
1068 
1069 	dbg("%s",__FUNCTION__);
1070 
1071 	priv = usb_get_serial_port_data(serial->port[0]);
1072 	udev = serial->dev;
1073 
1074 	/* XXX I've no idea if the original SIO supports the event_char
1075 	 * sysfs parameter, so I'm playing it safe.  */
1076 	if (priv->chip_type != SIO) {
1077 		dbg("sysfs attributes for %s", ftdi_chip_name[priv->chip_type]);
1078 		device_create_file(&udev->dev, &dev_attr_event_char);
1079 		if (priv->chip_type == FT232BM || priv->chip_type == FT2232C) {
1080 			device_create_file(&udev->dev, &dev_attr_latency_timer);
1081 		}
1082 	}
1083 }
1084 
1085 static void remove_sysfs_attrs(struct usb_serial *serial)
1086 {
1087 	struct ftdi_private *priv;
1088 	struct usb_device *udev;
1089 
1090 	dbg("%s",__FUNCTION__);
1091 
1092 	priv = usb_get_serial_port_data(serial->port[0]);
1093 	udev = serial->dev;
1094 
1095 	/* XXX see create_sysfs_attrs */
1096 	if (priv->chip_type != SIO) {
1097 		device_remove_file(&udev->dev, &dev_attr_event_char);
1098 		if (priv->chip_type == FT232BM || priv->chip_type == FT2232C) {
1099 			device_remove_file(&udev->dev, &dev_attr_latency_timer);
1100 		}
1101 	}
1102 
1103 }
1104 
1105 /*
1106  * ***************************************************************************
1107  * FTDI driver specific functions
1108  * ***************************************************************************
1109  */
1110 
1111 /* Probe function to check for special devices */
1112 static int ftdi_sio_probe (struct usb_serial *serial, const struct usb_device_id *id)
1113 {
1114 	usb_set_serial_data(serial, (void *)id->driver_info);
1115 
1116 	return (0);
1117 }
1118 
1119 /* attach subroutine */
1120 static int ftdi_sio_attach (struct usb_serial *serial)
1121 {
1122 	struct usb_serial_port *port = serial->port[0];
1123 	struct ftdi_private *priv;
1124 	struct ftdi_sio_quirk *quirk;
1125 
1126 	dbg("%s",__FUNCTION__);
1127 
1128 	priv = kmalloc(sizeof(struct ftdi_private), GFP_KERNEL);
1129 	if (!priv){
1130 		err("%s- kmalloc(%Zd) failed.", __FUNCTION__, sizeof(struct ftdi_private));
1131 		return -ENOMEM;
1132 	}
1133 	memset(priv, 0, sizeof(*priv));
1134 
1135 	spin_lock_init(&priv->rx_lock);
1136         init_waitqueue_head(&priv->delta_msr_wait);
1137 	/* This will push the characters through immediately rather
1138 	   than queue a task to deliver them */
1139 	priv->flags = ASYNC_LOW_LATENCY;
1140 
1141 	/* Increase the size of read buffers */
1142 	kfree(port->bulk_in_buffer);
1143 	port->bulk_in_buffer = kmalloc (BUFSZ, GFP_KERNEL);
1144 	if (!port->bulk_in_buffer) {
1145 		kfree (priv);
1146 		return -ENOMEM;
1147 	}
1148 	if (port->read_urb) {
1149 		port->read_urb->transfer_buffer = port->bulk_in_buffer;
1150 		port->read_urb->transfer_buffer_length = BUFSZ;
1151 	}
1152 
1153 	INIT_WORK(&priv->rx_work, ftdi_process_read, port);
1154 
1155 	/* Free port's existing write urb and transfer buffer. */
1156 	if (port->write_urb) {
1157 		usb_free_urb (port->write_urb);
1158 		port->write_urb = NULL;
1159 	}
1160 	kfree(port->bulk_out_buffer);
1161 	port->bulk_out_buffer = NULL;
1162 
1163 	usb_set_serial_port_data(serial->port[0], priv);
1164 
1165 	ftdi_determine_type (serial->port[0]);
1166 	create_sysfs_attrs(serial);
1167 
1168 	/* Check for device requiring special set up. */
1169 	quirk = (struct ftdi_sio_quirk *)usb_get_serial_data(serial);
1170 	if (quirk && quirk->setup) {
1171 		quirk->setup(serial);
1172 	}
1173 
1174 	return (0);
1175 } /* ftdi_sio_attach */
1176 
1177 
1178 /* Setup for the USB-UIRT device, which requires hardwired
1179  * baudrate (38400 gets mapped to 312500) */
1180 /* Called from usbserial:serial_probe */
1181 static void ftdi_USB_UIRT_setup (struct usb_serial *serial)
1182 {
1183 	struct ftdi_private *priv;
1184 
1185 	dbg("%s",__FUNCTION__);
1186 
1187 	priv = usb_get_serial_port_data(serial->port[0]);
1188 	priv->flags |= ASYNC_SPD_CUST;
1189 	priv->custom_divisor = 77;
1190 	priv->force_baud = B38400;
1191 } /* ftdi_USB_UIRT_setup */
1192 
1193 /* Setup for the HE-TIRA1 device, which requires hardwired
1194  * baudrate (38400 gets mapped to 100000) and RTS-CTS enabled.  */
1195 static void ftdi_HE_TIRA1_setup (struct usb_serial *serial)
1196 {
1197 	struct ftdi_private *priv;
1198 
1199 	dbg("%s",__FUNCTION__);
1200 
1201 	priv = usb_get_serial_port_data(serial->port[0]);
1202 	priv->flags |= ASYNC_SPD_CUST;
1203 	priv->custom_divisor = 240;
1204 	priv->force_baud = B38400;
1205 	priv->force_rtscts = 1;
1206 } /* ftdi_HE_TIRA1_setup */
1207 
1208 
1209 /* ftdi_shutdown is called from usbserial:usb_serial_disconnect
1210  *   it is called when the usb device is disconnected
1211  *
1212  *   usbserial:usb_serial_disconnect
1213  *      calls __serial_close for each open of the port
1214  *      shutdown is called then (ie ftdi_shutdown)
1215  */
1216 
1217 
1218 static void ftdi_shutdown (struct usb_serial *serial)
1219 { /* ftdi_shutdown */
1220 
1221 	struct usb_serial_port *port = serial->port[0];
1222 	struct ftdi_private *priv = usb_get_serial_port_data(port);
1223 
1224 	dbg("%s", __FUNCTION__);
1225 
1226 	remove_sysfs_attrs(serial);
1227 
1228 	/* all open ports are closed at this point
1229          *    (by usbserial.c:__serial_close, which calls ftdi_close)
1230 	 */
1231 
1232 	if (priv) {
1233 		usb_set_serial_port_data(port, NULL);
1234 		kfree(priv);
1235 	}
1236 } /* ftdi_shutdown */
1237 
1238 
1239 static int  ftdi_open (struct usb_serial_port *port, struct file *filp)
1240 { /* ftdi_open */
1241 	struct termios tmp_termios;
1242 	struct usb_device *dev = port->serial->dev;
1243 	struct ftdi_private *priv = usb_get_serial_port_data(port);
1244 	unsigned long flags;
1245 
1246 	int result = 0;
1247 	char buf[1]; /* Needed for the usb_control_msg I think */
1248 
1249 	dbg("%s", __FUNCTION__);
1250 
1251 
1252 	port->tty->low_latency = (priv->flags & ASYNC_LOW_LATENCY) ? 1 : 0;
1253 
1254 	/* No error checking for this (will get errors later anyway) */
1255 	/* See ftdi_sio.h for description of what is reset */
1256 	usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
1257 			FTDI_SIO_RESET_REQUEST, FTDI_SIO_RESET_REQUEST_TYPE,
1258 			FTDI_SIO_RESET_SIO,
1259 			priv->interface, buf, 0, WDR_TIMEOUT);
1260 
1261 	/* Termios defaults are set by usb_serial_init. We don't change
1262 	   port->tty->termios - this would loose speed settings, etc.
1263 	   This is same behaviour as serial.c/rs_open() - Kuba */
1264 
1265 	/* ftdi_set_termios  will send usb control messages */
1266 	ftdi_set_termios(port, &tmp_termios);
1267 
1268 	/* FIXME: Flow control might be enabled, so it should be checked -
1269 	   we have no control of defaults! */
1270 	/* Turn on RTS and DTR since we are not flow controlling by default */
1271 	set_mctrl(port, TIOCM_DTR | TIOCM_RTS);
1272 
1273 	/* Not throttled */
1274 	spin_lock_irqsave(&priv->rx_lock, flags);
1275 	priv->rx_flags &= ~(THROTTLED | ACTUALLY_THROTTLED);
1276 	spin_unlock_irqrestore(&priv->rx_lock, flags);
1277 
1278 	/* Start reading from the device */
1279 	priv->rx_processed = 0;
1280 	usb_fill_bulk_urb(port->read_urb, dev,
1281 		      usb_rcvbulkpipe(dev, port->bulk_in_endpointAddress),
1282 		      port->read_urb->transfer_buffer, port->read_urb->transfer_buffer_length,
1283 		      ftdi_read_bulk_callback, port);
1284 	result = usb_submit_urb(port->read_urb, GFP_KERNEL);
1285 	if (result)
1286 		err("%s - failed submitting read urb, error %d", __FUNCTION__, result);
1287 
1288 
1289 	return result;
1290 } /* ftdi_open */
1291 
1292 
1293 
1294 /*
1295  * usbserial:__serial_close  only calls ftdi_close if the point is open
1296  *
1297  *   This only gets called when it is the last close
1298  *
1299  *
1300  */
1301 
1302 static void ftdi_close (struct usb_serial_port *port, struct file *filp)
1303 { /* ftdi_close */
1304 	unsigned int c_cflag = port->tty->termios->c_cflag;
1305 	struct ftdi_private *priv = usb_get_serial_port_data(port);
1306 	char buf[1];
1307 
1308 	dbg("%s", __FUNCTION__);
1309 
1310 	if (c_cflag & HUPCL){
1311 		/* Disable flow control */
1312 		if (usb_control_msg(port->serial->dev,
1313 				    usb_sndctrlpipe(port->serial->dev, 0),
1314 				    FTDI_SIO_SET_FLOW_CTRL_REQUEST,
1315 				    FTDI_SIO_SET_FLOW_CTRL_REQUEST_TYPE,
1316 				    0, priv->interface, buf, 0,
1317 				    WDR_TIMEOUT) < 0) {
1318 			err("error from flowcontrol urb");
1319 		}
1320 
1321 		/* drop RTS and DTR */
1322 		clear_mctrl(port, TIOCM_DTR | TIOCM_RTS);
1323 	} /* Note change no line if hupcl is off */
1324 
1325 	/* cancel any scheduled reading */
1326 	cancel_delayed_work(&priv->rx_work);
1327 	flush_scheduled_work();
1328 
1329 	/* shutdown our bulk read */
1330 	if (port->read_urb)
1331 		usb_kill_urb(port->read_urb);
1332 } /* ftdi_close */
1333 
1334 
1335 
1336 /* The SIO requires the first byte to have:
1337  *  B0 1
1338  *  B1 0
1339  *  B2..7 length of message excluding byte 0
1340  *
1341  * The new devices do not require this byte
1342  */
1343 static int ftdi_write (struct usb_serial_port *port,
1344 			   const unsigned char *buf, int count)
1345 { /* ftdi_write */
1346 	struct ftdi_private *priv = usb_get_serial_port_data(port);
1347 	struct urb *urb;
1348 	unsigned char *buffer;
1349 	int data_offset ;       /* will be 1 for the SIO and 0 otherwise */
1350 	int status;
1351 	int transfer_size;
1352 
1353 	dbg("%s port %d, %d bytes", __FUNCTION__, port->number, count);
1354 
1355 	if (count == 0) {
1356 		dbg("write request of 0 bytes");
1357 		return 0;
1358 	}
1359 
1360 	data_offset = priv->write_offset;
1361         dbg("data_offset set to %d",data_offset);
1362 
1363 	/* Determine total transfer size */
1364 	transfer_size = count;
1365 	if (data_offset > 0) {
1366 		/* Original sio needs control bytes too... */
1367 		transfer_size += (data_offset *
1368 				((count + (PKTSZ - 1 - data_offset)) /
1369 				 (PKTSZ - data_offset)));
1370 	}
1371 
1372 	buffer = kmalloc (transfer_size, GFP_ATOMIC);
1373 	if (!buffer) {
1374 		err("%s ran out of kernel memory for urb ...", __FUNCTION__);
1375 		return -ENOMEM;
1376 	}
1377 
1378 	urb = usb_alloc_urb(0, GFP_ATOMIC);
1379 	if (!urb) {
1380 		err("%s - no more free urbs", __FUNCTION__);
1381 		kfree (buffer);
1382 		return -ENOMEM;
1383 	}
1384 
1385 	/* Copy data */
1386 	if (data_offset > 0) {
1387 		/* Original sio requires control byte at start of each packet. */
1388 		int user_pktsz = PKTSZ - data_offset;
1389 		int todo = count;
1390 		unsigned char *first_byte = buffer;
1391 		const unsigned char *current_position = buf;
1392 
1393 		while (todo > 0) {
1394 			if (user_pktsz > todo) {
1395 				user_pktsz = todo;
1396 			}
1397 			/* Write the control byte at the front of the packet*/
1398 			*first_byte = 1 | ((user_pktsz) << 2);
1399 			/* Copy data for packet */
1400 			memcpy (first_byte + data_offset,
1401 				current_position, user_pktsz);
1402 			first_byte += user_pktsz + data_offset;
1403 			current_position += user_pktsz;
1404 			todo -= user_pktsz;
1405 		}
1406 	} else {
1407 		/* No control byte required. */
1408 		/* Copy in the data to send */
1409 		memcpy (buffer, buf, count);
1410 	}
1411 
1412 	usb_serial_debug_data(debug, &port->dev, __FUNCTION__, transfer_size, buffer);
1413 
1414 	/* fill the buffer and send it */
1415 	usb_fill_bulk_urb(urb, port->serial->dev,
1416 		      usb_sndbulkpipe(port->serial->dev, port->bulk_out_endpointAddress),
1417 		      buffer, transfer_size,
1418 		      ftdi_write_bulk_callback, port);
1419 
1420 	status = usb_submit_urb(urb, GFP_ATOMIC);
1421 	if (status) {
1422 		err("%s - failed submitting write urb, error %d", __FUNCTION__, status);
1423 		count = status;
1424 		kfree (buffer);
1425 	}
1426 
1427 	/* we are done with this urb, so let the host driver
1428 	 * really free it when it is finished with it */
1429 	usb_free_urb (urb);
1430 
1431 	dbg("%s write returning: %d", __FUNCTION__, count);
1432 	return count;
1433 } /* ftdi_write */
1434 
1435 
1436 /* This function may get called when the device is closed */
1437 
1438 static void ftdi_write_bulk_callback (struct urb *urb, struct pt_regs *regs)
1439 {
1440 	struct usb_serial_port *port = (struct usb_serial_port *)urb->context;
1441 
1442 	/* free up the transfer buffer, as usb_free_urb() does not do this */
1443 	kfree (urb->transfer_buffer);
1444 
1445 	dbg("%s - port %d", __FUNCTION__, port->number);
1446 
1447 	if (urb->status) {
1448 		dbg("nonzero write bulk status received: %d", urb->status);
1449 		return;
1450 	}
1451 
1452 	schedule_work(&port->work);
1453 } /* ftdi_write_bulk_callback */
1454 
1455 
1456 static int ftdi_write_room( struct usb_serial_port *port )
1457 {
1458 	dbg("%s - port %d", __FUNCTION__, port->number);
1459 
1460 	/*
1461 	 * We really can take anything the user throws at us
1462 	 * but let's pick a nice big number to tell the tty
1463 	 * layer that we have lots of free space
1464 	 */
1465 	return 2048;
1466 } /* ftdi_write_room */
1467 
1468 
1469 static int ftdi_chars_in_buffer (struct usb_serial_port *port)
1470 { /* ftdi_chars_in_buffer */
1471 	dbg("%s - port %d", __FUNCTION__, port->number);
1472 
1473 	/*
1474 	 * We can't really account for how much data we
1475 	 * have sent out, but hasn't made it through to the
1476 	 * device, so just tell the tty layer that everything
1477 	 * is flushed.
1478 	 */
1479 	return 0;
1480 } /* ftdi_chars_in_buffer */
1481 
1482 
1483 
1484 static void ftdi_read_bulk_callback (struct urb *urb, struct pt_regs *regs)
1485 { /* ftdi_read_bulk_callback */
1486 	struct usb_serial_port *port = (struct usb_serial_port *)urb->context;
1487 	struct tty_struct *tty;
1488 	struct ftdi_private *priv;
1489 
1490 	if (urb->number_of_packets > 0) {
1491 		err("%s transfer_buffer_length %d actual_length %d number of packets %d",__FUNCTION__,
1492 		    urb->transfer_buffer_length, urb->actual_length, urb->number_of_packets );
1493 		err("%s transfer_flags %x ", __FUNCTION__,urb->transfer_flags );
1494 	}
1495 
1496 	dbg("%s - port %d", __FUNCTION__, port->number);
1497 
1498 	if (port->open_count <= 0)
1499 		return;
1500 
1501 	tty = port->tty;
1502 	if (!tty) {
1503 		dbg("%s - bad tty pointer - exiting",__FUNCTION__);
1504 		return;
1505 	}
1506 
1507 	priv = usb_get_serial_port_data(port);
1508 	if (!priv) {
1509 		dbg("%s - bad port private data pointer - exiting", __FUNCTION__);
1510 		return;
1511 	}
1512 
1513 	if (urb != port->read_urb) {
1514 		err("%s - Not my urb!", __FUNCTION__);
1515 	}
1516 
1517 	if (urb->status) {
1518 		/* This will happen at close every time so it is a dbg not an err */
1519 		dbg("(this is ok on close) nonzero read bulk status received: %d", urb->status);
1520 		return;
1521 	}
1522 
1523 	ftdi_process_read(port);
1524 
1525 } /* ftdi_read_bulk_callback */
1526 
1527 
1528 static void ftdi_process_read (void *param)
1529 { /* ftdi_process_read */
1530 	struct usb_serial_port *port = (struct usb_serial_port*)param;
1531 	struct urb *urb;
1532 	struct tty_struct *tty;
1533 	struct ftdi_private *priv;
1534 	char error_flag;
1535        	unsigned char *data;
1536 
1537 	int i;
1538 	int result;
1539 	int need_flip;
1540 	int packet_offset;
1541 	unsigned long flags;
1542 
1543 	dbg("%s - port %d", __FUNCTION__, port->number);
1544 
1545 	if (port->open_count <= 0)
1546 		return;
1547 
1548 	tty = port->tty;
1549 	if (!tty) {
1550 		dbg("%s - bad tty pointer - exiting",__FUNCTION__);
1551 		return;
1552 	}
1553 
1554 	priv = usb_get_serial_port_data(port);
1555 	if (!priv) {
1556 		dbg("%s - bad port private data pointer - exiting", __FUNCTION__);
1557 		return;
1558 	}
1559 
1560 	urb = port->read_urb;
1561 	if (!urb) {
1562 		dbg("%s - bad read_urb pointer - exiting", __FUNCTION__);
1563 		return;
1564 	}
1565 
1566 	data = urb->transfer_buffer;
1567 
1568 	if (priv->rx_processed) {
1569 		dbg("%s - already processed: %d bytes, %d remain", __FUNCTION__,
1570 				priv->rx_processed,
1571 				urb->actual_length - priv->rx_processed);
1572 	} else {
1573 		/* The first two bytes of every read packet are status */
1574 		if (urb->actual_length > 2) {
1575 			usb_serial_debug_data(debug, &port->dev, __FUNCTION__, urb->actual_length, data);
1576 		} else {
1577 			dbg("Status only: %03oo %03oo",data[0],data[1]);
1578 		}
1579 	}
1580 
1581 
1582 	/* TO DO -- check for hung up line and handle appropriately: */
1583 	/*   send hangup  */
1584 	/* See acm.c - you do a tty_hangup  - eg tty_hangup(tty) */
1585 	/* if CD is dropped and the line is not CLOCAL then we should hangup */
1586 
1587 	need_flip = 0;
1588 	for (packet_offset = priv->rx_processed; packet_offset < urb->actual_length; packet_offset += PKTSZ) {
1589 		int length;
1590 
1591 		/* Compare new line status to the old one, signal if different */
1592 		/* N.B. packet may be processed more than once, but differences
1593 		 * are only processed once.  */
1594 		if (priv != NULL) {
1595 			char new_status = data[packet_offset+0] & FTDI_STATUS_B0_MASK;
1596 			if (new_status != priv->prev_status) {
1597 				priv->diff_status |= new_status ^ priv->prev_status;
1598 				wake_up_interruptible(&priv->delta_msr_wait);
1599 				priv->prev_status = new_status;
1600 			}
1601 		}
1602 
1603 		length = min(PKTSZ, urb->actual_length-packet_offset)-2;
1604 		if (length < 0) {
1605 			err("%s - bad packet length: %d", __FUNCTION__, length+2);
1606 			length = 0;
1607 		}
1608 
1609 		/* have to make sure we don't overflow the buffer
1610 		   with tty_insert_flip_char's */
1611 		if (tty->flip.count+length > TTY_FLIPBUF_SIZE) {
1612 			tty_flip_buffer_push(tty);
1613 			need_flip = 0;
1614 
1615 			if (tty->flip.count != 0) {
1616 				/* flip didn't work, this happens when ftdi_process_read() is
1617 				 * called from ftdi_unthrottle, because TTY_DONT_FLIP is set */
1618 				dbg("%s - flip buffer push failed", __FUNCTION__);
1619 				break;
1620 			}
1621 		}
1622 		if (priv->rx_flags & THROTTLED) {
1623 			dbg("%s - throttled", __FUNCTION__);
1624 			break;
1625 		}
1626 		if (tty->ldisc.receive_room(tty)-tty->flip.count < length) {
1627 			/* break out & wait for throttling/unthrottling to happen */
1628 			dbg("%s - receive room low", __FUNCTION__);
1629 			break;
1630 		}
1631 
1632 		/* Handle errors and break */
1633 		error_flag = TTY_NORMAL;
1634 		/* Although the device uses a bitmask and hence can have multiple */
1635 		/* errors on a packet - the order here sets the priority the */
1636 		/* error is returned to the tty layer  */
1637 
1638 		if ( data[packet_offset+1] & FTDI_RS_OE ) {
1639 			error_flag = TTY_OVERRUN;
1640 			dbg("OVERRRUN error");
1641 		}
1642 		if ( data[packet_offset+1] & FTDI_RS_BI ) {
1643 			error_flag = TTY_BREAK;
1644 			dbg("BREAK received");
1645 		}
1646 		if ( data[packet_offset+1] & FTDI_RS_PE ) {
1647 			error_flag = TTY_PARITY;
1648 			dbg("PARITY error");
1649 		}
1650 		if ( data[packet_offset+1] & FTDI_RS_FE ) {
1651 			error_flag = TTY_FRAME;
1652 			dbg("FRAMING error");
1653 		}
1654 		if (length > 0) {
1655 			for (i = 2; i < length+2; i++) {
1656 				/* Note that the error flag is duplicated for
1657 				   every character received since we don't know
1658 				   which character it applied to */
1659 				tty_insert_flip_char(tty, data[packet_offset+i], error_flag);
1660 			}
1661 			need_flip = 1;
1662 		}
1663 
1664 #ifdef NOT_CORRECT_BUT_KEEPING_IT_FOR_NOW
1665 		/* if a parity error is detected you get status packets forever
1666 		   until a character is sent without a parity error.
1667 		   This doesn't work well since the application receives a never
1668 		   ending stream of bad data - even though new data hasn't been sent.
1669 		   Therefore I (bill) have taken this out.
1670 		   However - this might make sense for framing errors and so on
1671 		   so I am leaving the code in for now.
1672 		*/
1673 		else {
1674 			if (error_flag != TTY_NORMAL){
1675 				dbg("error_flag is not normal");
1676 				/* In this case it is just status - if that is an error send a bad character */
1677 				if(tty->flip.count >= TTY_FLIPBUF_SIZE) {
1678 					tty_flip_buffer_push(tty);
1679 				}
1680 				tty_insert_flip_char(tty, 0xff, error_flag);
1681 				need_flip = 1;
1682 			}
1683 		}
1684 #endif
1685 	} /* "for(packet_offset=0..." */
1686 
1687 	/* Low latency */
1688 	if (need_flip) {
1689 		tty_flip_buffer_push(tty);
1690 	}
1691 
1692 	if (packet_offset < urb->actual_length) {
1693 		/* not completely processed - record progress */
1694 		priv->rx_processed = packet_offset;
1695 		dbg("%s - incomplete, %d bytes processed, %d remain",
1696 				__FUNCTION__, packet_offset,
1697 				urb->actual_length - packet_offset);
1698 		/* check if we were throttled while processing */
1699 		spin_lock_irqsave(&priv->rx_lock, flags);
1700 		if (priv->rx_flags & THROTTLED) {
1701 			priv->rx_flags |= ACTUALLY_THROTTLED;
1702 			spin_unlock_irqrestore(&priv->rx_lock, flags);
1703 			dbg("%s - deferring remainder until unthrottled",
1704 					__FUNCTION__);
1705 			return;
1706 		}
1707 		spin_unlock_irqrestore(&priv->rx_lock, flags);
1708 		/* if the port is closed stop trying to read */
1709 		if (port->open_count > 0){
1710 			/* delay processing of remainder */
1711 			schedule_delayed_work(&priv->rx_work, 1);
1712 		} else {
1713 			dbg("%s - port is closed", __FUNCTION__);
1714 		}
1715 		return;
1716 	}
1717 
1718 	/* urb is completely processed */
1719 	priv->rx_processed = 0;
1720 
1721 	/* if the port is closed stop trying to read */
1722 	if (port->open_count > 0){
1723 		/* Continue trying to always read  */
1724 		usb_fill_bulk_urb(port->read_urb, port->serial->dev,
1725 			      usb_rcvbulkpipe(port->serial->dev, port->bulk_in_endpointAddress),
1726 			      port->read_urb->transfer_buffer, port->read_urb->transfer_buffer_length,
1727 			      ftdi_read_bulk_callback, port);
1728 
1729 		result = usb_submit_urb(port->read_urb, GFP_ATOMIC);
1730 		if (result)
1731 			err("%s - failed resubmitting read urb, error %d", __FUNCTION__, result);
1732 	}
1733 
1734 	return;
1735 } /* ftdi_process_read */
1736 
1737 
1738 static void ftdi_break_ctl( struct usb_serial_port *port, int break_state )
1739 {
1740 	struct ftdi_private *priv = usb_get_serial_port_data(port);
1741 	__u16 urb_value = 0;
1742 	char buf[1];
1743 
1744 	/* break_state = -1 to turn on break, and 0 to turn off break */
1745 	/* see drivers/char/tty_io.c to see it used */
1746 	/* last_set_data_urb_value NEVER has the break bit set in it */
1747 
1748 	if (break_state) {
1749 		urb_value = priv->last_set_data_urb_value | FTDI_SIO_SET_BREAK;
1750 	} else {
1751 		urb_value = priv->last_set_data_urb_value;
1752 	}
1753 
1754 
1755 	if (usb_control_msg(port->serial->dev, usb_sndctrlpipe(port->serial->dev, 0),
1756 			    FTDI_SIO_SET_DATA_REQUEST,
1757 			    FTDI_SIO_SET_DATA_REQUEST_TYPE,
1758 			    urb_value , priv->interface,
1759 			    buf, 0, WDR_TIMEOUT) < 0) {
1760 		err("%s FAILED to enable/disable break state (state was %d)", __FUNCTION__,break_state);
1761 	}
1762 
1763 	dbg("%s break state is %d - urb is %d", __FUNCTION__,break_state, urb_value);
1764 
1765 }
1766 
1767 
1768 /* old_termios contains the original termios settings and tty->termios contains
1769  * the new setting to be used
1770  * WARNING: set_termios calls this with old_termios in kernel space
1771  */
1772 
1773 static void ftdi_set_termios (struct usb_serial_port *port, struct termios *old_termios)
1774 { /* ftdi_termios */
1775 	struct usb_device *dev = port->serial->dev;
1776 	unsigned int cflag = port->tty->termios->c_cflag;
1777 	struct ftdi_private *priv = usb_get_serial_port_data(port);
1778 	__u16 urb_value; /* will hold the new flags */
1779 	char buf[1]; /* Perhaps I should dynamically alloc this? */
1780 
1781 	// Added for xon/xoff support
1782 	unsigned int iflag = port->tty->termios->c_iflag;
1783 	unsigned char vstop;
1784 	unsigned char vstart;
1785 
1786 	dbg("%s", __FUNCTION__);
1787 
1788 	/* Force baud rate if this device requires it, unless it is set to B0. */
1789 	if (priv->force_baud && ((port->tty->termios->c_cflag & CBAUD) != B0)) {
1790 		dbg("%s: forcing baud rate for this device", __FUNCTION__);
1791 		port->tty->termios->c_cflag &= ~CBAUD;
1792 		port->tty->termios->c_cflag |= priv->force_baud;
1793 	}
1794 
1795 	/* Force RTS-CTS if this device requires it. */
1796 	if (priv->force_rtscts) {
1797 		dbg("%s: forcing rtscts for this device", __FUNCTION__);
1798 		port->tty->termios->c_cflag |= CRTSCTS;
1799 	}
1800 
1801 	cflag = port->tty->termios->c_cflag;
1802 
1803 	/* FIXME -For this cut I don't care if the line is really changing or
1804 	   not  - so just do the change regardless  - should be able to
1805 	   compare old_termios and tty->termios */
1806 	/* NOTE These routines can get interrupted by
1807 	   ftdi_sio_read_bulk_callback  - need to examine what this
1808            means - don't see any problems yet */
1809 
1810 	/* Set number of data bits, parity, stop bits */
1811 
1812 	urb_value = 0;
1813 	urb_value |= (cflag & CSTOPB ? FTDI_SIO_SET_DATA_STOP_BITS_2 :
1814 		      FTDI_SIO_SET_DATA_STOP_BITS_1);
1815 	urb_value |= (cflag & PARENB ?
1816 		      (cflag & PARODD ? FTDI_SIO_SET_DATA_PARITY_ODD :
1817 		       FTDI_SIO_SET_DATA_PARITY_EVEN) :
1818 		      FTDI_SIO_SET_DATA_PARITY_NONE);
1819 	if (cflag & CSIZE) {
1820 		switch (cflag & CSIZE) {
1821 		case CS5: urb_value |= 5; dbg("Setting CS5"); break;
1822 		case CS6: urb_value |= 6; dbg("Setting CS6"); break;
1823 		case CS7: urb_value |= 7; dbg("Setting CS7"); break;
1824 		case CS8: urb_value |= 8; dbg("Setting CS8"); break;
1825 		default:
1826 			err("CSIZE was set but not CS5-CS8");
1827 		}
1828 	}
1829 
1830 	/* This is needed by the break command since it uses the same command - but is
1831 	 *  or'ed with this value  */
1832 	priv->last_set_data_urb_value = urb_value;
1833 
1834 	if (usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
1835 			    FTDI_SIO_SET_DATA_REQUEST,
1836 			    FTDI_SIO_SET_DATA_REQUEST_TYPE,
1837 			    urb_value , priv->interface,
1838 			    buf, 0, WDR_SHORT_TIMEOUT) < 0) {
1839 		err("%s FAILED to set databits/stopbits/parity", __FUNCTION__);
1840 	}
1841 
1842 	/* Now do the baudrate */
1843 	if ((cflag & CBAUD) == B0 ) {
1844 		/* Disable flow control */
1845 		if (usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
1846 				    FTDI_SIO_SET_FLOW_CTRL_REQUEST,
1847 				    FTDI_SIO_SET_FLOW_CTRL_REQUEST_TYPE,
1848 				    0, priv->interface,
1849 				    buf, 0, WDR_TIMEOUT) < 0) {
1850 			err("%s error from disable flowcontrol urb", __FUNCTION__);
1851 		}
1852 		/* Drop RTS and DTR */
1853 		clear_mctrl(port, TIOCM_DTR | TIOCM_RTS);
1854 	} else {
1855 		/* set the baudrate determined before */
1856 		if (change_speed(port)) {
1857 			err("%s urb failed to set baudrate", __FUNCTION__);
1858 		}
1859 		/* Ensure RTS and DTR are raised when baudrate changed from 0 */
1860 		if ((old_termios->c_cflag & CBAUD) == B0) {
1861 			set_mctrl(port, TIOCM_DTR | TIOCM_RTS);
1862 		}
1863 	}
1864 
1865 	/* Set flow control */
1866 	/* Note device also supports DTR/CD (ugh) and Xon/Xoff in hardware */
1867 	if (cflag & CRTSCTS) {
1868 		dbg("%s Setting to CRTSCTS flow control", __FUNCTION__);
1869 		if (usb_control_msg(dev,
1870 				    usb_sndctrlpipe(dev, 0),
1871 				    FTDI_SIO_SET_FLOW_CTRL_REQUEST,
1872 				    FTDI_SIO_SET_FLOW_CTRL_REQUEST_TYPE,
1873 				    0 , (FTDI_SIO_RTS_CTS_HS | priv->interface),
1874 				    buf, 0, WDR_TIMEOUT) < 0) {
1875 			err("urb failed to set to rts/cts flow control");
1876 		}
1877 
1878 	} else {
1879 		/*
1880 		 * Xon/Xoff code
1881 		 *
1882 		 * Check the IXOFF status in the iflag component of the termios structure
1883 		 * if IXOFF is not set, the pre-xon/xoff code is executed.
1884 		*/
1885 		if (iflag & IXOFF) {
1886 			dbg("%s  request to enable xonxoff iflag=%04x",__FUNCTION__,iflag);
1887 			// Try to enable the XON/XOFF on the ftdi_sio
1888 			// Set the vstart and vstop -- could have been done up above where
1889 			// a lot of other dereferencing is done but that would be very
1890 			// inefficient as vstart and vstop are not always needed
1891 			vstart=port->tty->termios->c_cc[VSTART];
1892 			vstop=port->tty->termios->c_cc[VSTOP];
1893 			urb_value=(vstop << 8) | (vstart);
1894 
1895 			if (usb_control_msg(dev,
1896 					    usb_sndctrlpipe(dev, 0),
1897 					    FTDI_SIO_SET_FLOW_CTRL_REQUEST,
1898 					    FTDI_SIO_SET_FLOW_CTRL_REQUEST_TYPE,
1899 					    urb_value , (FTDI_SIO_XON_XOFF_HS
1900 							 | priv->interface),
1901 					    buf, 0, WDR_TIMEOUT) < 0) {
1902 				err("urb failed to set to xon/xoff flow control");
1903 			}
1904 		} else {
1905 			/* else clause to only run if cfag ! CRTSCTS and iflag ! XOFF */
1906 			/* CHECKME Assuming XON/XOFF handled by tty stack - not by device */
1907 			dbg("%s Turning off hardware flow control", __FUNCTION__);
1908 			if (usb_control_msg(dev,
1909 					    usb_sndctrlpipe(dev, 0),
1910 					    FTDI_SIO_SET_FLOW_CTRL_REQUEST,
1911 					    FTDI_SIO_SET_FLOW_CTRL_REQUEST_TYPE,
1912 					    0, priv->interface,
1913 					    buf, 0, WDR_TIMEOUT) < 0) {
1914 				err("urb failed to clear flow control");
1915 			}
1916 		}
1917 
1918 	}
1919 	return;
1920 } /* ftdi_termios */
1921 
1922 
1923 static int ftdi_tiocmget (struct usb_serial_port *port, struct file *file)
1924 {
1925 	struct ftdi_private *priv = usb_get_serial_port_data(port);
1926 	unsigned char buf[2];
1927 	int ret;
1928 
1929 	dbg("%s TIOCMGET", __FUNCTION__);
1930 	switch (priv->chip_type) {
1931 	case SIO:
1932 		/* Request the status from the device */
1933 		if ((ret = usb_control_msg(port->serial->dev,
1934 					   usb_rcvctrlpipe(port->serial->dev, 0),
1935 					   FTDI_SIO_GET_MODEM_STATUS_REQUEST,
1936 					   FTDI_SIO_GET_MODEM_STATUS_REQUEST_TYPE,
1937 					   0, 0,
1938 					   buf, 1, WDR_TIMEOUT)) < 0 ) {
1939 			err("%s Could not get modem status of device - err: %d", __FUNCTION__,
1940 			    ret);
1941 			return(ret);
1942 		}
1943 		break;
1944 	case FT8U232AM:
1945 	case FT232BM:
1946 	case FT2232C:
1947 		/* the 8U232AM returns a two byte value (the sio is a 1 byte value) - in the same
1948 		   format as the data returned from the in point */
1949 		if ((ret = usb_control_msg(port->serial->dev,
1950 					   usb_rcvctrlpipe(port->serial->dev, 0),
1951 					   FTDI_SIO_GET_MODEM_STATUS_REQUEST,
1952 					   FTDI_SIO_GET_MODEM_STATUS_REQUEST_TYPE,
1953 					   0, priv->interface,
1954 					   buf, 2, WDR_TIMEOUT)) < 0 ) {
1955 			err("%s Could not get modem status of device - err: %d", __FUNCTION__,
1956 			    ret);
1957 			return(ret);
1958 		}
1959 		break;
1960 	default:
1961 		return -EFAULT;
1962 		break;
1963 	}
1964 
1965 	return  (buf[0] & FTDI_SIO_DSR_MASK ? TIOCM_DSR : 0) |
1966 		(buf[0] & FTDI_SIO_CTS_MASK ? TIOCM_CTS : 0) |
1967 		(buf[0]  & FTDI_SIO_RI_MASK  ? TIOCM_RI  : 0) |
1968 		(buf[0]  & FTDI_SIO_RLSD_MASK ? TIOCM_CD  : 0) |
1969 		priv->last_dtr_rts;
1970 }
1971 
1972 static int ftdi_tiocmset(struct usb_serial_port *port, struct file * file, unsigned int set, unsigned int clear)
1973 {
1974 	dbg("%s TIOCMSET", __FUNCTION__);
1975 	return update_mctrl(port, set, clear);
1976 }
1977 
1978 
1979 static int ftdi_ioctl (struct usb_serial_port *port, struct file * file, unsigned int cmd, unsigned long arg)
1980 {
1981 	struct ftdi_private *priv = usb_get_serial_port_data(port);
1982 
1983 	dbg("%s cmd 0x%04x", __FUNCTION__, cmd);
1984 
1985 	/* Based on code from acm.c and others */
1986 	switch (cmd) {
1987 
1988 	case TIOCGSERIAL: /* gets serial port data */
1989 		return get_serial_info(port, (struct serial_struct __user *) arg);
1990 
1991 	case TIOCSSERIAL: /* sets serial port data */
1992 		return set_serial_info(port, (struct serial_struct __user *) arg);
1993 
1994 	/*
1995 	 * Wait for any of the 4 modem inputs (DCD,RI,DSR,CTS) to change
1996 	 * - mask passed in arg for lines of interest
1997 	 *   (use |'ed TIOCM_RNG/DSR/CD/CTS for masking)
1998 	 * Caller should use TIOCGICOUNT to see which one it was.
1999 	 *
2000 	 * This code is borrowed from linux/drivers/char/serial.c
2001 	 */
2002 	case TIOCMIWAIT:
2003 		while (priv != NULL) {
2004 			interruptible_sleep_on(&priv->delta_msr_wait);
2005 			/* see if a signal did it */
2006 			if (signal_pending(current))
2007 				return -ERESTARTSYS;
2008 			else {
2009 				char diff = priv->diff_status;
2010 
2011 				if (diff == 0) {
2012 					return -EIO; /* no change => error */
2013 				}
2014 
2015 				/* Consume all events */
2016 				priv->diff_status = 0;
2017 
2018 				/* Return 0 if caller wanted to know about these bits */
2019 				if ( ((arg & TIOCM_RNG) && (diff & FTDI_RS0_RI)) ||
2020 				     ((arg & TIOCM_DSR) && (diff & FTDI_RS0_DSR)) ||
2021 				     ((arg & TIOCM_CD)  && (diff & FTDI_RS0_RLSD)) ||
2022 				     ((arg & TIOCM_CTS) && (diff & FTDI_RS0_CTS)) ) {
2023 					return 0;
2024 				}
2025 				/*
2026 				 * Otherwise caller can't care less about what happened,
2027 				 * and so we continue to wait for more events.
2028 				 */
2029 			}
2030 		}
2031 		return(0);
2032 		break;
2033 	default:
2034 		break;
2035 
2036 	}
2037 
2038 
2039 	/* This is not necessarily an error - turns out the higher layers will do
2040 	 *  some ioctls itself (see comment above)
2041 	 */
2042 	dbg("%s arg not supported - it was 0x%04x - check /usr/include/asm/ioctls.h", __FUNCTION__, cmd);
2043 
2044 	return(-ENOIOCTLCMD);
2045 } /* ftdi_ioctl */
2046 
2047 
2048 static void ftdi_throttle (struct usb_serial_port *port)
2049 {
2050 	struct ftdi_private *priv = usb_get_serial_port_data(port);
2051 	unsigned long flags;
2052 
2053 	dbg("%s - port %d", __FUNCTION__, port->number);
2054 
2055 	spin_lock_irqsave(&priv->rx_lock, flags);
2056 	priv->rx_flags |= THROTTLED;
2057 	spin_unlock_irqrestore(&priv->rx_lock, flags);
2058 }
2059 
2060 
2061 static void ftdi_unthrottle (struct usb_serial_port *port)
2062 {
2063 	struct ftdi_private *priv = usb_get_serial_port_data(port);
2064 	int actually_throttled;
2065 	unsigned long flags;
2066 
2067 	dbg("%s - port %d", __FUNCTION__, port->number);
2068 
2069 	spin_lock_irqsave(&priv->rx_lock, flags);
2070 	actually_throttled = priv->rx_flags & ACTUALLY_THROTTLED;
2071 	priv->rx_flags &= ~(THROTTLED | ACTUALLY_THROTTLED);
2072 	spin_unlock_irqrestore(&priv->rx_lock, flags);
2073 
2074 	if (actually_throttled)
2075 		schedule_work(&priv->rx_work);
2076 }
2077 
2078 static int __init ftdi_init (void)
2079 {
2080 	int retval;
2081 
2082 	dbg("%s", __FUNCTION__);
2083 	if (vendor > 0 && product > 0) {
2084 		/* Add user specified VID/PID to reserved element of table. */
2085 		int i;
2086 		for (i = 0; id_table_combined[i].idVendor; i++)
2087 			;
2088 		id_table_combined[i].match_flags = USB_DEVICE_ID_MATCH_DEVICE;
2089 		id_table_combined[i].idVendor = vendor;
2090 		id_table_combined[i].idProduct = product;
2091 	}
2092 	retval = usb_serial_register(&ftdi_sio_device);
2093 	if (retval)
2094 		goto failed_sio_register;
2095 	retval = usb_register(&ftdi_driver);
2096 	if (retval)
2097 		goto failed_usb_register;
2098 
2099 	info(DRIVER_VERSION ":" DRIVER_DESC);
2100 	return 0;
2101 failed_usb_register:
2102 	usb_serial_deregister(&ftdi_sio_device);
2103 failed_sio_register:
2104 	return retval;
2105 }
2106 
2107 
2108 static void __exit ftdi_exit (void)
2109 {
2110 
2111 	dbg("%s", __FUNCTION__);
2112 
2113 	usb_deregister (&ftdi_driver);
2114 	usb_serial_deregister (&ftdi_sio_device);
2115 
2116 }
2117 
2118 
2119 module_init(ftdi_init);
2120 module_exit(ftdi_exit);
2121 
2122 MODULE_AUTHOR( DRIVER_AUTHOR );
2123 MODULE_DESCRIPTION( DRIVER_DESC );
2124 MODULE_LICENSE("GPL");
2125 
2126 module_param(debug, bool, S_IRUGO | S_IWUSR);
2127 MODULE_PARM_DESC(debug, "Debug enabled or not");
2128 module_param(vendor, ushort, 0);
2129 MODULE_PARM_DESC(vendor, "User specified vendor ID (default="
2130 		__MODULE_STRING(FTDI_VID)")");
2131 module_param(product, ushort, 0);
2132 MODULE_PARM_DESC(vendor, "User specified product ID");
2133 
2134