xref: /linux/drivers/usb/serial/ftdi_sio.c (revision 20d0021394c1b070bf04b22c5bc8fdb437edd4c5)
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 
273 /* struct ftdi_sio_quirk is used by devices requiring special attention. */
274 struct ftdi_sio_quirk {
275 	void (*setup)(struct usb_serial *); /* Special settings during startup. */
276 };
277 
278 static void  ftdi_USB_UIRT_setup	(struct usb_serial *serial);
279 static void  ftdi_HE_TIRA1_setup	(struct usb_serial *serial);
280 
281 static struct ftdi_sio_quirk ftdi_USB_UIRT_quirk = {
282 	.setup = ftdi_USB_UIRT_setup,
283 };
284 
285 static struct ftdi_sio_quirk ftdi_HE_TIRA1_quirk = {
286 	.setup = ftdi_HE_TIRA1_setup,
287 };
288 
289 /*
290  * The 8U232AM has the same API as the sio except for:
291  * - it can support MUCH higher baudrates; up to:
292  *   o 921600 for RS232 and 2000000 for RS422/485 at 48MHz
293  *   o 230400 at 12MHz
294  *   so .. 8U232AM's baudrate setting codes are different
295  * - it has a two byte status code.
296  * - it returns characters every 16ms (the FTDI does it every 40ms)
297  *
298  * the bcdDevice value is used to differentiate FT232BM and FT245BM from
299  * the earlier FT8U232AM and FT8U232BM.  For now, include all known VID/PID
300  * combinations in both tables.
301  * FIXME: perhaps bcdDevice can also identify 12MHz FT8U232AM devices,
302  * but I don't know if those ever went into mass production. [Ian Abbott]
303  */
304 
305 
306 
307 static struct usb_device_id id_table_combined [] = {
308 	{ USB_DEVICE(FTDI_VID, FTDI_IRTRANS_PID) },
309 	{ USB_DEVICE(FTDI_VID, FTDI_SIO_PID) },
310 	{ USB_DEVICE(FTDI_VID, FTDI_8U232AM_PID) },
311 	{ USB_DEVICE(FTDI_VID, FTDI_8U232AM_ALT_PID) },
312 	{ USB_DEVICE(FTDI_VID, FTDI_8U2232C_PID) },
313 	{ USB_DEVICE(FTDI_VID, FTDI_RELAIS_PID) },
314 	{ USB_DEVICE(INTERBIOMETRICS_VID, INTERBIOMETRICS_IOBOARD_PID) },
315 	{ USB_DEVICE(INTERBIOMETRICS_VID, INTERBIOMETRICS_MINI_IOBOARD_PID) },
316 	{ USB_DEVICE(FTDI_VID, FTDI_XF_632_PID) },
317 	{ USB_DEVICE(FTDI_VID, FTDI_XF_634_PID) },
318 	{ USB_DEVICE(FTDI_VID, FTDI_XF_547_PID) },
319 	{ USB_DEVICE(FTDI_VID, FTDI_XF_633_PID) },
320 	{ USB_DEVICE(FTDI_VID, FTDI_XF_631_PID) },
321 	{ USB_DEVICE(FTDI_VID, FTDI_XF_635_PID) },
322 	{ USB_DEVICE(FTDI_VID, FTDI_XF_640_PID) },
323 	{ USB_DEVICE(FTDI_VID, FTDI_XF_642_PID) },
324 	{ USB_DEVICE(FTDI_VID, FTDI_DSS20_PID) },
325 	{ USB_DEVICE(FTDI_NF_RIC_VID, FTDI_NF_RIC_PID) },
326 	{ USB_DEVICE(FTDI_VID, FTDI_VNHCPCUSB_D_PID) },
327 	{ USB_DEVICE(FTDI_VID, FTDI_MTXORB_0_PID) },
328 	{ USB_DEVICE(FTDI_VID, FTDI_MTXORB_1_PID) },
329 	{ USB_DEVICE(FTDI_VID, FTDI_MTXORB_2_PID) },
330 	{ USB_DEVICE(FTDI_VID, FTDI_MTXORB_3_PID) },
331 	{ USB_DEVICE(FTDI_VID, FTDI_MTXORB_4_PID) },
332 	{ USB_DEVICE(FTDI_VID, FTDI_MTXORB_5_PID) },
333 	{ USB_DEVICE(FTDI_VID, FTDI_MTXORB_6_PID) },
334 	{ USB_DEVICE(FTDI_VID, FTDI_PERLE_ULTRAPORT_PID) },
335 	{ USB_DEVICE(FTDI_VID, FTDI_PIEGROUP_PID) },
336 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2101_PID) },
337 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2102_PID) },
338 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2103_PID) },
339 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2104_PID) },
340 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2201_1_PID) },
341 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2201_2_PID) },
342 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2202_1_PID) },
343 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2202_2_PID) },
344 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2203_1_PID) },
345 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2203_2_PID) },
346 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2401_1_PID) },
347 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2401_2_PID) },
348 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2401_3_PID) },
349 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2401_4_PID) },
350 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2402_1_PID) },
351 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2402_2_PID) },
352 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2402_3_PID) },
353 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2402_4_PID) },
354 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2403_1_PID) },
355 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2403_2_PID) },
356 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2403_3_PID) },
357 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2403_4_PID) },
358 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2801_1_PID) },
359 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2801_2_PID) },
360 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2801_3_PID) },
361 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2801_4_PID) },
362 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2801_5_PID) },
363 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2801_6_PID) },
364 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2801_7_PID) },
365 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2801_8_PID) },
366 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2802_1_PID) },
367 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2802_2_PID) },
368 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2802_3_PID) },
369 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2802_4_PID) },
370 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2802_5_PID) },
371 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2802_6_PID) },
372 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2802_7_PID) },
373 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2802_8_PID) },
374 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2803_1_PID) },
375 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2803_2_PID) },
376 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2803_3_PID) },
377 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2803_4_PID) },
378 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2803_5_PID) },
379 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2803_6_PID) },
380 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2803_7_PID) },
381 	{ USB_DEVICE(SEALEVEL_VID, SEALEVEL_2803_8_PID) },
382 	{ USB_DEVICE(IDTECH_VID, IDTECH_IDT1221U_PID) },
383 	{ USB_DEVICE(OCT_VID, OCT_US101_PID) },
384 	{ USB_DEVICE(FTDI_VID, FTDI_HE_TIRA1_PID),
385 		.driver_info = (kernel_ulong_t)&ftdi_HE_TIRA1_quirk },
386 	{ USB_DEVICE(FTDI_VID, FTDI_USB_UIRT_PID),
387 		.driver_info = (kernel_ulong_t)&ftdi_USB_UIRT_quirk },
388 	{ USB_DEVICE(FTDI_VID, PROTEGO_SPECIAL_1) },
389 	{ USB_DEVICE(FTDI_VID, PROTEGO_R2X0) },
390 	{ USB_DEVICE(FTDI_VID, PROTEGO_SPECIAL_3) },
391 	{ USB_DEVICE(FTDI_VID, PROTEGO_SPECIAL_4) },
392 	{ USB_DEVICE(FTDI_VID, FTDI_GUDEADS_E808_PID) },
393 	{ USB_DEVICE(FTDI_VID, FTDI_GUDEADS_E809_PID) },
394 	{ USB_DEVICE(FTDI_VID, FTDI_GUDEADS_E80A_PID) },
395 	{ USB_DEVICE(FTDI_VID, FTDI_GUDEADS_E80B_PID) },
396 	{ USB_DEVICE(FTDI_VID, FTDI_GUDEADS_E80C_PID) },
397 	{ USB_DEVICE(FTDI_VID, FTDI_GUDEADS_E80D_PID) },
398 	{ USB_DEVICE(FTDI_VID, FTDI_GUDEADS_E80E_PID) },
399 	{ USB_DEVICE(FTDI_VID, FTDI_GUDEADS_E80F_PID) },
400 	{ USB_DEVICE(FTDI_VID, FTDI_GUDEADS_E888_PID) },
401 	{ USB_DEVICE(FTDI_VID, FTDI_GUDEADS_E889_PID) },
402 	{ USB_DEVICE(FTDI_VID, FTDI_GUDEADS_E88A_PID) },
403 	{ USB_DEVICE(FTDI_VID, FTDI_GUDEADS_E88B_PID) },
404 	{ USB_DEVICE(FTDI_VID, FTDI_GUDEADS_E88C_PID) },
405 	{ USB_DEVICE(FTDI_VID, FTDI_GUDEADS_E88D_PID) },
406 	{ USB_DEVICE(FTDI_VID, FTDI_GUDEADS_E88E_PID) },
407 	{ USB_DEVICE(FTDI_VID, FTDI_GUDEADS_E88F_PID) },
408 	{ USB_DEVICE(FTDI_VID, FTDI_ELV_UO100_PID) },
409 	{ USB_DEVICE(FTDI_VID, FTDI_ELV_UM100_PID) },
410  	{ USB_DEVICE(FTDI_VID, LINX_SDMUSBQSS_PID) },
411  	{ USB_DEVICE(FTDI_VID, LINX_MASTERDEVEL2_PID) },
412  	{ USB_DEVICE(FTDI_VID, LINX_FUTURE_0_PID) },
413  	{ USB_DEVICE(FTDI_VID, LINX_FUTURE_1_PID) },
414  	{ USB_DEVICE(FTDI_VID, LINX_FUTURE_2_PID) },
415  	{ USB_DEVICE(FTDI_VID, FTDI_CCSICDU20_0_PID) },
416  	{ USB_DEVICE(FTDI_VID, FTDI_CCSICDU40_1_PID) },
417 	{ USB_DEVICE(FTDI_VID, INSIDE_ACCESSO) },
418 	{ USB_DEVICE(INTREPID_VID, INTREPID_VALUECAN_PID) },
419 	{ USB_DEVICE(INTREPID_VID, INTREPID_NEOVI_PID) },
420 	{ USB_DEVICE(FALCOM_VID, FALCOM_TWIST_PID) },
421 	{ USB_DEVICE(FTDI_VID, FTDI_SUUNTO_SPORTS_PID) },
422 	{ USB_DEVICE(FTDI_VID, FTDI_RM_CANVIEW_PID) },
423 	{ USB_DEVICE(BANDB_VID, BANDB_USOTL4_PID) },
424 	{ USB_DEVICE(BANDB_VID, BANDB_USTL4_PID) },
425 	{ USB_DEVICE(BANDB_VID, BANDB_USO9ML2_PID) },
426 	{ USB_DEVICE(FTDI_VID, EVER_ECO_PRO_CDS) },
427 	{ USB_DEVICE(FTDI_VID, FTDI_4N_GALAXY_DE_0_PID) },
428 	{ USB_DEVICE(FTDI_VID, FTDI_4N_GALAXY_DE_1_PID) },
429 	{ USB_DEVICE(FTDI_VID, FTDI_4N_GALAXY_DE_2_PID) },
430 	{ USB_DEVICE(MOBILITY_VID, MOBILITY_USB_SERIAL_PID) },
431 	{ USB_DEVICE(FTDI_VID, FTDI_ACTIVE_ROBOTS_PID) },
432 	{ }						/* Terminating entry */
433 };
434 
435 MODULE_DEVICE_TABLE (usb, id_table_combined);
436 
437 static struct usb_driver ftdi_driver = {
438 	.name =		"ftdi_sio",
439 	.probe =	usb_serial_probe,
440 	.disconnect =	usb_serial_disconnect,
441 	.id_table =	id_table_combined,
442 };
443 
444 static char *ftdi_chip_name[] = {
445 	[SIO] = "SIO",	/* the serial part of FT8U100AX */
446 	[FT8U232AM] = "FT8U232AM",
447 	[FT232BM] = "FT232BM",
448 	[FT2232C] = "FT2232C",
449 };
450 
451 
452 /* Constants for read urb and write urb */
453 #define BUFSZ 512
454 #define PKTSZ 64
455 
456 /* rx_flags */
457 #define THROTTLED		0x01
458 #define ACTUALLY_THROTTLED	0x02
459 
460 struct ftdi_private {
461 	ftdi_chip_type_t chip_type;
462 				/* type of the device, either SIO or FT8U232AM */
463 	int baud_base;		/* baud base clock for divisor setting */
464 	int custom_divisor;	/* custom_divisor kludge, this is for baud_base (different from what goes to the chip!) */
465 	__u16 last_set_data_urb_value ;
466 				/* the last data state set - needed for doing a break */
467         int write_offset;       /* This is the offset in the usb data block to write the serial data -
468 				 * it is different between devices
469 				 */
470 	int flags;		/* some ASYNC_xxxx flags are supported */
471 	unsigned long last_dtr_rts;	/* saved modem control outputs */
472         wait_queue_head_t delta_msr_wait; /* Used for TIOCMIWAIT */
473  	char prev_status, diff_status;        /* Used for TIOCMIWAIT */
474 	__u8 rx_flags;		/* receive state flags (throttling) */
475 	spinlock_t rx_lock;	/* spinlock for receive state */
476 	struct work_struct rx_work;
477 	int rx_processed;
478 
479 	__u16 interface;	/* FT2232C port interface (0 for FT232/245) */
480 
481 	int force_baud;		/* if non-zero, force the baud rate to this value */
482 	int force_rtscts;	/* if non-zero, force RTS-CTS to always be enabled */
483 };
484 
485 /* Used for TIOCMIWAIT */
486 #define FTDI_STATUS_B0_MASK	(FTDI_RS0_CTS | FTDI_RS0_DSR | FTDI_RS0_RI | FTDI_RS0_RLSD)
487 #define FTDI_STATUS_B1_MASK	(FTDI_RS_BI)
488 /* End TIOCMIWAIT */
489 
490 #define FTDI_IMPL_ASYNC_FLAGS = ( ASYNC_SPD_HI | ASYNC_SPD_VHI \
491  ASYNC_SPD_CUST | ASYNC_SPD_SHI | ASYNC_SPD_WARP )
492 
493 /* function prototypes for a FTDI serial converter */
494 static int  ftdi_sio_probe	(struct usb_serial *serial, const struct usb_device_id *id);
495 static int  ftdi_sio_attach		(struct usb_serial *serial);
496 static void ftdi_shutdown		(struct usb_serial *serial);
497 static int  ftdi_open			(struct usb_serial_port *port, struct file *filp);
498 static void ftdi_close			(struct usb_serial_port *port, struct file *filp);
499 static int  ftdi_write			(struct usb_serial_port *port, const unsigned char *buf, int count);
500 static int  ftdi_write_room		(struct usb_serial_port *port);
501 static int  ftdi_chars_in_buffer	(struct usb_serial_port *port);
502 static void ftdi_write_bulk_callback	(struct urb *urb, struct pt_regs *regs);
503 static void ftdi_read_bulk_callback	(struct urb *urb, struct pt_regs *regs);
504 static void ftdi_process_read		(void *param);
505 static void ftdi_set_termios		(struct usb_serial_port *port, struct termios * old);
506 static int  ftdi_tiocmget               (struct usb_serial_port *port, struct file *file);
507 static int  ftdi_tiocmset		(struct usb_serial_port *port, struct file * file, unsigned int set, unsigned int clear);
508 static int  ftdi_ioctl			(struct usb_serial_port *port, struct file * file, unsigned int cmd, unsigned long arg);
509 static void ftdi_break_ctl		(struct usb_serial_port *port, int break_state );
510 static void ftdi_throttle		(struct usb_serial_port *port);
511 static void ftdi_unthrottle		(struct usb_serial_port *port);
512 
513 static unsigned short int ftdi_232am_baud_base_to_divisor (int baud, int base);
514 static unsigned short int ftdi_232am_baud_to_divisor (int baud);
515 static __u32 ftdi_232bm_baud_base_to_divisor (int baud, int base);
516 static __u32 ftdi_232bm_baud_to_divisor (int baud);
517 
518 static struct usb_serial_device_type ftdi_sio_device = {
519 	.owner =		THIS_MODULE,
520 	.name =			"FTDI USB Serial Device",
521 	.short_name =		"ftdi_sio",
522 	.id_table =		id_table_combined,
523 	.num_interrupt_in =	0,
524 	.num_bulk_in =		1,
525 	.num_bulk_out =		1,
526 	.num_ports =		1,
527 	.probe =		ftdi_sio_probe,
528 	.open =			ftdi_open,
529 	.close =		ftdi_close,
530 	.throttle =		ftdi_throttle,
531 	.unthrottle =		ftdi_unthrottle,
532 	.write =		ftdi_write,
533 	.write_room =		ftdi_write_room,
534 	.chars_in_buffer =	ftdi_chars_in_buffer,
535 	.read_bulk_callback =	ftdi_read_bulk_callback,
536 	.write_bulk_callback =	ftdi_write_bulk_callback,
537 	.tiocmget =             ftdi_tiocmget,
538 	.tiocmset =             ftdi_tiocmset,
539 	.ioctl =		ftdi_ioctl,
540 	.set_termios =		ftdi_set_termios,
541 	.break_ctl =		ftdi_break_ctl,
542 	.attach =		ftdi_sio_attach,
543 	.shutdown =		ftdi_shutdown,
544 };
545 
546 
547 #define WDR_TIMEOUT 5000 /* default urb timeout */
548 
549 /* High and low are for DTR, RTS etc etc */
550 #define HIGH 1
551 #define LOW 0
552 
553 /*
554  * ***************************************************************************
555  * Utlity functions
556  * ***************************************************************************
557  */
558 
559 static unsigned short int ftdi_232am_baud_base_to_divisor(int baud, int base)
560 {
561 	unsigned short int divisor;
562 	int divisor3 = base / 2 / baud; // divisor shifted 3 bits to the left
563 	if ((divisor3 & 0x7) == 7) divisor3 ++; // round x.7/8 up to x+1
564 	divisor = divisor3 >> 3;
565 	divisor3 &= 0x7;
566 	if (divisor3 == 1) divisor |= 0xc000; else // 0.125
567 	if (divisor3 >= 4) divisor |= 0x4000; else // 0.5
568 	if (divisor3 != 0) divisor |= 0x8000;      // 0.25
569 	if (divisor == 1) divisor = 0;	/* special case for maximum baud rate */
570 	return divisor;
571 }
572 
573 static unsigned short int ftdi_232am_baud_to_divisor(int baud)
574 {
575 	 return(ftdi_232am_baud_base_to_divisor(baud, 48000000));
576 }
577 
578 static __u32 ftdi_232bm_baud_base_to_divisor(int baud, int base)
579 {
580 	static const unsigned char divfrac[8] = { 0, 3, 2, 4, 1, 5, 6, 7 };
581 	__u32 divisor;
582 	int divisor3 = base / 2 / baud; // divisor shifted 3 bits to the left
583 	divisor = divisor3 >> 3;
584 	divisor |= (__u32)divfrac[divisor3 & 0x7] << 14;
585 	/* Deal with special cases for highest baud rates. */
586 	if (divisor == 1) divisor = 0; else	// 1.0
587 	if (divisor == 0x4001) divisor = 1;	// 1.5
588 	return divisor;
589 }
590 
591 static __u32 ftdi_232bm_baud_to_divisor(int baud)
592 {
593 	 return(ftdi_232bm_baud_base_to_divisor(baud, 48000000));
594 }
595 
596 static int set_rts(struct usb_serial_port *port, int high_or_low)
597 {
598 	struct ftdi_private *priv = usb_get_serial_port_data(port);
599 	char *buf;
600 	unsigned ftdi_high_or_low;
601 	int rv;
602 
603 	buf = kmalloc(1, GFP_NOIO);
604 	if (!buf)
605 		return -ENOMEM;
606 
607 	if (high_or_low) {
608 		ftdi_high_or_low = FTDI_SIO_SET_RTS_HIGH;
609 		priv->last_dtr_rts |= TIOCM_RTS;
610 	} else {
611 		ftdi_high_or_low = FTDI_SIO_SET_RTS_LOW;
612 		priv->last_dtr_rts &= ~TIOCM_RTS;
613 	}
614 	rv = usb_control_msg(port->serial->dev,
615 			       usb_sndctrlpipe(port->serial->dev, 0),
616 			       FTDI_SIO_SET_MODEM_CTRL_REQUEST,
617 			       FTDI_SIO_SET_MODEM_CTRL_REQUEST_TYPE,
618 			       ftdi_high_or_low, priv->interface,
619 			       buf, 0, WDR_TIMEOUT);
620 
621 	kfree(buf);
622 	return rv;
623 }
624 
625 
626 static int set_dtr(struct usb_serial_port *port, int high_or_low)
627 {
628 	struct ftdi_private *priv = usb_get_serial_port_data(port);
629 	char *buf;
630 	unsigned ftdi_high_or_low;
631 	int rv;
632 
633 	buf = kmalloc(1, GFP_NOIO);
634 	if (!buf)
635 		return -ENOMEM;
636 
637 	if (high_or_low) {
638 		ftdi_high_or_low = FTDI_SIO_SET_DTR_HIGH;
639 		priv->last_dtr_rts |= TIOCM_DTR;
640 	} else {
641 		ftdi_high_or_low = FTDI_SIO_SET_DTR_LOW;
642 		priv->last_dtr_rts &= ~TIOCM_DTR;
643 	}
644 	rv = usb_control_msg(port->serial->dev,
645 			       usb_sndctrlpipe(port->serial->dev, 0),
646 			       FTDI_SIO_SET_MODEM_CTRL_REQUEST,
647 			       FTDI_SIO_SET_MODEM_CTRL_REQUEST_TYPE,
648 			       ftdi_high_or_low, priv->interface,
649 			       buf, 0, WDR_TIMEOUT);
650 
651 	kfree(buf);
652 	return rv;
653 }
654 
655 
656 static __u32 get_ftdi_divisor(struct usb_serial_port * port);
657 
658 
659 static int change_speed(struct usb_serial_port *port)
660 {
661 	struct ftdi_private *priv = usb_get_serial_port_data(port);
662 	char *buf;
663         __u16 urb_value;
664 	__u16 urb_index;
665 	__u32 urb_index_value;
666 	int rv;
667 
668 	buf = kmalloc(1, GFP_NOIO);
669 	if (!buf)
670 		return -ENOMEM;
671 
672 	urb_index_value = get_ftdi_divisor(port);
673 	urb_value = (__u16)urb_index_value;
674 	urb_index = (__u16)(urb_index_value >> 16);
675 	if (priv->interface) {	/* FT2232C */
676 		urb_index = (__u16)((urb_index << 8) | priv->interface);
677 	}
678 
679 	rv = usb_control_msg(port->serial->dev,
680 			    usb_sndctrlpipe(port->serial->dev, 0),
681 			    FTDI_SIO_SET_BAUDRATE_REQUEST,
682 			    FTDI_SIO_SET_BAUDRATE_REQUEST_TYPE,
683 			    urb_value, urb_index,
684 			    buf, 0, 100);
685 
686 	kfree(buf);
687 	return rv;
688 }
689 
690 
691 static __u32 get_ftdi_divisor(struct usb_serial_port * port)
692 { /* get_ftdi_divisor */
693 	struct ftdi_private *priv = usb_get_serial_port_data(port);
694 	__u32 div_value = 0;
695 	int div_okay = 1;
696 	int baud;
697 
698 	/*
699 	 * The logic involved in setting the baudrate can be cleanly split in 3 steps.
700 	 * Obtaining the actual baud rate is a little tricky since unix traditionally
701 	 * somehow ignored the possibility to set non-standard baud rates.
702 	 * 1. Standard baud rates are set in tty->termios->c_cflag
703 	 * 2. If these are not enough, you can set any speed using alt_speed as follows:
704 	 *    - set tty->termios->c_cflag speed to B38400
705 	 *    - set your real speed in tty->alt_speed; it gets ignored when
706 	 *      alt_speed==0, (or)
707 	 *    - call TIOCSSERIAL ioctl with (struct serial_struct) set as follows:
708 	 *      flags & ASYNC_SPD_MASK == ASYNC_SPD_[HI, VHI, SHI, WARP], this just
709 	 *      sets alt_speed to (HI: 57600, VHI: 115200, SHI: 230400, WARP: 460800)
710 	 * ** Steps 1, 2 are done courtesy of tty_get_baud_rate
711 	 * 3. You can also set baud rate by setting custom divisor as follows
712 	 *    - set tty->termios->c_cflag speed to B38400
713 	 *    - call TIOCSSERIAL ioctl with (struct serial_struct) set as follows:
714 	 *      o flags & ASYNC_SPD_MASK == ASYNC_SPD_CUST
715 	 *      o custom_divisor set to baud_base / your_new_baudrate
716 	 * ** Step 3 is done courtesy of code borrowed from serial.c - I should really
717 	 *    spend some time and separate+move this common code to serial.c, it is
718 	 *    replicated in nearly every serial driver you see.
719 	 */
720 
721 	/* 1. Get the baud rate from the tty settings, this observes alt_speed hack */
722 
723 	baud = tty_get_baud_rate(port->tty);
724 	dbg("%s - tty_get_baud_rate reports speed %d", __FUNCTION__, baud);
725 
726 	/* 2. Observe async-compatible custom_divisor hack, update baudrate if needed */
727 
728 	if (baud == 38400 &&
729 	    ((priv->flags & ASYNC_SPD_MASK) == ASYNC_SPD_CUST) &&
730 	     (priv->custom_divisor)) {
731 		baud = priv->baud_base / priv->custom_divisor;
732 		dbg("%s - custom divisor %d sets baud rate to %d", __FUNCTION__, priv->custom_divisor, baud);
733 	}
734 
735 	/* 3. Convert baudrate to device-specific divisor */
736 
737 	if (!baud) baud = 9600;
738 	switch(priv->chip_type) {
739 	case SIO: /* SIO chip */
740 		switch(baud) {
741 		case 300: div_value = ftdi_sio_b300; break;
742 		case 600: div_value = ftdi_sio_b600; break;
743 		case 1200: div_value = ftdi_sio_b1200; break;
744 		case 2400: div_value = ftdi_sio_b2400; break;
745 		case 4800: div_value = ftdi_sio_b4800; break;
746 		case 9600: div_value = ftdi_sio_b9600; break;
747 		case 19200: div_value = ftdi_sio_b19200; break;
748 		case 38400: div_value = ftdi_sio_b38400; break;
749 		case 57600: div_value = ftdi_sio_b57600;  break;
750 		case 115200: div_value = ftdi_sio_b115200; break;
751 		} /* baud */
752 		if (div_value == 0) {
753   			dbg("%s - Baudrate (%d) requested is not supported", __FUNCTION__,  baud);
754 			div_value = ftdi_sio_b9600;
755 			div_okay = 0;
756 		}
757 		break;
758 	case FT8U232AM: /* 8U232AM chip */
759 		if (baud <= 3000000) {
760 			div_value = ftdi_232am_baud_to_divisor(baud);
761 		} else {
762 	                dbg("%s - Baud rate too high!", __FUNCTION__);
763 			div_value = ftdi_232am_baud_to_divisor(9600);
764 			div_okay = 0;
765 		}
766 		break;
767 	case FT232BM: /* FT232BM chip */
768 	case FT2232C: /* FT2232C chip */
769 		if (baud <= 3000000) {
770 			div_value = ftdi_232bm_baud_to_divisor(baud);
771 		} else {
772 	                dbg("%s - Baud rate too high!", __FUNCTION__);
773 			div_value = ftdi_232bm_baud_to_divisor(9600);
774 			div_okay = 0;
775 		}
776 		break;
777 	} /* priv->chip_type */
778 
779 	if (div_okay) {
780 		dbg("%s - Baud rate set to %d (divisor 0x%lX) on chip %s",
781 			__FUNCTION__, baud, (unsigned long)div_value,
782 			ftdi_chip_name[priv->chip_type]);
783 	}
784 
785 	return(div_value);
786 }
787 
788 
789 static int get_serial_info(struct usb_serial_port * port, struct serial_struct __user * retinfo)
790 {
791 	struct ftdi_private *priv = usb_get_serial_port_data(port);
792 	struct serial_struct tmp;
793 
794 	if (!retinfo)
795 		return -EFAULT;
796 	memset(&tmp, 0, sizeof(tmp));
797 	tmp.flags = priv->flags;
798 	tmp.baud_base = priv->baud_base;
799 	tmp.custom_divisor = priv->custom_divisor;
800 	if (copy_to_user(retinfo, &tmp, sizeof(*retinfo)))
801 		return -EFAULT;
802 	return 0;
803 } /* get_serial_info */
804 
805 
806 static int set_serial_info(struct usb_serial_port * port, struct serial_struct __user * newinfo)
807 { /* set_serial_info */
808 	struct ftdi_private *priv = usb_get_serial_port_data(port);
809 	struct serial_struct new_serial;
810 	struct ftdi_private old_priv;
811 
812 	if (copy_from_user(&new_serial, newinfo, sizeof(new_serial)))
813 		return -EFAULT;
814 	old_priv = * priv;
815 
816 	/* Do error checking and permission checking */
817 
818 	if (!capable(CAP_SYS_ADMIN)) {
819 		if (((new_serial.flags & ~ASYNC_USR_MASK) !=
820 		     (priv->flags & ~ASYNC_USR_MASK)))
821 			return -EPERM;
822 		priv->flags = ((priv->flags & ~ASYNC_USR_MASK) |
823 			       (new_serial.flags & ASYNC_USR_MASK));
824 		priv->custom_divisor = new_serial.custom_divisor;
825 		goto check_and_exit;
826 	}
827 
828 	if ((new_serial.baud_base != priv->baud_base) &&
829 	    (new_serial.baud_base < 9600))
830 		return -EINVAL;
831 
832 	/* Make the changes - these are privileged changes! */
833 
834 	priv->flags = ((priv->flags & ~ASYNC_FLAGS) |
835 	               (new_serial.flags & ASYNC_FLAGS));
836 	priv->custom_divisor = new_serial.custom_divisor;
837 
838 	port->tty->low_latency = (priv->flags & ASYNC_LOW_LATENCY) ? 1 : 0;
839 
840 check_and_exit:
841 	if ((old_priv.flags & ASYNC_SPD_MASK) !=
842 	     (priv->flags & ASYNC_SPD_MASK)) {
843 		if ((priv->flags & ASYNC_SPD_MASK) == ASYNC_SPD_HI)
844 			port->tty->alt_speed = 57600;
845 		else if ((priv->flags & ASYNC_SPD_MASK) == ASYNC_SPD_VHI)
846 			port->tty->alt_speed = 115200;
847 		else if ((priv->flags & ASYNC_SPD_MASK) == ASYNC_SPD_SHI)
848 			port->tty->alt_speed = 230400;
849 		else if ((priv->flags & ASYNC_SPD_MASK) == ASYNC_SPD_WARP)
850 			port->tty->alt_speed = 460800;
851 		else
852 			port->tty->alt_speed = 0;
853 	}
854 	if (((old_priv.flags & ASYNC_SPD_MASK) !=
855 	     (priv->flags & ASYNC_SPD_MASK)) ||
856 	    (((priv->flags & ASYNC_SPD_MASK) == ASYNC_SPD_CUST) &&
857 	     (old_priv.custom_divisor != priv->custom_divisor))) {
858 		change_speed(port);
859 	}
860 
861 	return (0);
862 
863 } /* set_serial_info */
864 
865 
866 /* Determine type of FTDI chip based on USB config and descriptor. */
867 static void ftdi_determine_type(struct usb_serial_port *port)
868 {
869 	struct ftdi_private *priv = usb_get_serial_port_data(port);
870 	struct usb_serial *serial = port->serial;
871 	struct usb_device *udev = serial->dev;
872 	unsigned version;
873 	unsigned interfaces;
874 
875 	/* Assume it is not the original SIO device for now. */
876 	priv->baud_base = 48000000 / 16;
877 	priv->write_offset = 0;
878 
879 	version = le16_to_cpu(udev->descriptor.bcdDevice);
880 	interfaces = udev->actconfig->desc.bNumInterfaces;
881 	dbg("%s: bcdDevice = 0x%x, bNumInterfaces = %u", __FUNCTION__,
882 			version, interfaces);
883 	if (interfaces > 1) {
884 		int inter;
885 
886 		/* Multiple interfaces.  Assume FT2232C. */
887 		priv->chip_type = FT2232C;
888 		/* Determine interface code. */
889 		inter = serial->interface->altsetting->desc.bInterfaceNumber;
890 		if (inter == 0) {
891 			priv->interface = PIT_SIOA;
892 		} else {
893 			priv->interface = PIT_SIOB;
894 		}
895 		/* BM-type devices have a bug where bcdDevice gets set
896 		 * to 0x200 when iSerialNumber is 0.  */
897 		if (version < 0x500) {
898 			dbg("%s: something fishy - bcdDevice too low for multi-interface device",
899 					__FUNCTION__);
900 		}
901 	} else if (version < 0x200) {
902 		/* Old device.  Assume its the original SIO. */
903 		priv->chip_type = SIO;
904 		priv->baud_base = 12000000 / 16;
905 		priv->write_offset = 1;
906 	} else if (version < 0x400) {
907 		/* Assume its an FT8U232AM (or FT8U245AM) */
908 		/* (It might be a BM because of the iSerialNumber bug,
909 		 * but it will still work as an AM device.) */
910 		priv->chip_type = FT8U232AM;
911 	} else {
912 		/* Assume its an FT232BM (or FT245BM) */
913 		priv->chip_type = FT232BM;
914 	}
915 	info("Detected %s", ftdi_chip_name[priv->chip_type]);
916 }
917 
918 
919 /*
920  * ***************************************************************************
921  * Sysfs Attribute
922  * ***************************************************************************
923  */
924 
925 static ssize_t show_latency_timer(struct device *dev, struct device_attribute *attr, char *buf)
926 {
927 	struct usb_serial_port *port = to_usb_serial_port(dev);
928 	struct ftdi_private *priv = usb_get_serial_port_data(port);
929 	struct usb_device *udev;
930 	unsigned short latency = 0;
931 	int rv = 0;
932 
933 	udev = to_usb_device(dev);
934 
935 	dbg("%s",__FUNCTION__);
936 
937 	rv = usb_control_msg(udev,
938 			     usb_rcvctrlpipe(udev, 0),
939 			     FTDI_SIO_GET_LATENCY_TIMER_REQUEST,
940 			     FTDI_SIO_GET_LATENCY_TIMER_REQUEST_TYPE,
941 			     0, priv->interface,
942 			     (char*) &latency, 1, WDR_TIMEOUT);
943 
944 	if (rv < 0) {
945 		dev_err(dev, "Unable to read latency timer: %i", rv);
946 		return -EIO;
947 	}
948 	return sprintf(buf, "%i\n", latency);
949 }
950 
951 /* Write a new value of the latency timer, in units of milliseconds. */
952 static ssize_t store_latency_timer(struct device *dev, struct device_attribute *attr, const char *valbuf,
953 				   size_t count)
954 {
955 	struct usb_serial_port *port = to_usb_serial_port(dev);
956 	struct ftdi_private *priv = usb_get_serial_port_data(port);
957 	struct usb_device *udev;
958 	char buf[1];
959 	int v = simple_strtoul(valbuf, NULL, 10);
960 	int rv = 0;
961 
962 	udev = to_usb_device(dev);
963 
964 	dbg("%s: setting latency timer = %i", __FUNCTION__, v);
965 
966 	rv = usb_control_msg(udev,
967 			     usb_sndctrlpipe(udev, 0),
968 			     FTDI_SIO_SET_LATENCY_TIMER_REQUEST,
969 			     FTDI_SIO_SET_LATENCY_TIMER_REQUEST_TYPE,
970 			     v, priv->interface,
971 			     buf, 0, WDR_TIMEOUT);
972 
973 	if (rv < 0) {
974 		dev_err(dev, "Unable to write latency timer: %i", rv);
975 		return -EIO;
976 	}
977 
978 	return count;
979 }
980 
981 /* Write an event character directly to the FTDI register.  The ASCII
982    value is in the low 8 bits, with the enable bit in the 9th bit. */
983 static ssize_t store_event_char(struct device *dev, struct device_attribute *attr, const char *valbuf,
984 				size_t count)
985 {
986 	struct usb_serial_port *port = to_usb_serial_port(dev);
987 	struct ftdi_private *priv = usb_get_serial_port_data(port);
988 	struct usb_device *udev;
989 	char buf[1];
990 	int v = simple_strtoul(valbuf, NULL, 10);
991 	int rv = 0;
992 
993 	udev = to_usb_device(dev);
994 
995 	dbg("%s: setting event char = %i", __FUNCTION__, v);
996 
997 	rv = usb_control_msg(udev,
998 			     usb_sndctrlpipe(udev, 0),
999 			     FTDI_SIO_SET_EVENT_CHAR_REQUEST,
1000 			     FTDI_SIO_SET_EVENT_CHAR_REQUEST_TYPE,
1001 			     v, priv->interface,
1002 			     buf, 0, WDR_TIMEOUT);
1003 
1004 	if (rv < 0) {
1005 		dbg("Unable to write event character: %i", rv);
1006 		return -EIO;
1007 	}
1008 
1009 	return count;
1010 }
1011 
1012 static DEVICE_ATTR(latency_timer, S_IWUSR | S_IRUGO, show_latency_timer, store_latency_timer);
1013 static DEVICE_ATTR(event_char, S_IWUSR, NULL, store_event_char);
1014 
1015 static void create_sysfs_attrs(struct usb_serial *serial)
1016 {
1017 	struct ftdi_private *priv;
1018 	struct usb_device *udev;
1019 
1020 	dbg("%s",__FUNCTION__);
1021 
1022 	priv = usb_get_serial_port_data(serial->port[0]);
1023 	udev = serial->dev;
1024 
1025 	/* XXX I've no idea if the original SIO supports the event_char
1026 	 * sysfs parameter, so I'm playing it safe.  */
1027 	if (priv->chip_type != SIO) {
1028 		dbg("sysfs attributes for %s", ftdi_chip_name[priv->chip_type]);
1029 		device_create_file(&udev->dev, &dev_attr_event_char);
1030 		if (priv->chip_type == FT232BM || priv->chip_type == FT2232C) {
1031 			device_create_file(&udev->dev, &dev_attr_latency_timer);
1032 		}
1033 	}
1034 }
1035 
1036 static void remove_sysfs_attrs(struct usb_serial *serial)
1037 {
1038 	struct ftdi_private *priv;
1039 	struct usb_device *udev;
1040 
1041 	dbg("%s",__FUNCTION__);
1042 
1043 	priv = usb_get_serial_port_data(serial->port[0]);
1044 	udev = serial->dev;
1045 
1046 	/* XXX see create_sysfs_attrs */
1047 	if (priv->chip_type != SIO) {
1048 		device_remove_file(&udev->dev, &dev_attr_event_char);
1049 		if (priv->chip_type == FT232BM || priv->chip_type == FT2232C) {
1050 			device_remove_file(&udev->dev, &dev_attr_latency_timer);
1051 		}
1052 	}
1053 
1054 }
1055 
1056 /*
1057  * ***************************************************************************
1058  * FTDI driver specific functions
1059  * ***************************************************************************
1060  */
1061 
1062 /* Probe function to check for special devices */
1063 static int ftdi_sio_probe (struct usb_serial *serial, const struct usb_device_id *id)
1064 {
1065 	usb_set_serial_data(serial, (void *)id->driver_info);
1066 
1067 	return (0);
1068 }
1069 
1070 /* attach subroutine */
1071 static int ftdi_sio_attach (struct usb_serial *serial)
1072 {
1073 	struct usb_serial_port *port = serial->port[0];
1074 	struct ftdi_private *priv;
1075 	struct ftdi_sio_quirk *quirk;
1076 
1077 	dbg("%s",__FUNCTION__);
1078 
1079 	priv = kmalloc(sizeof(struct ftdi_private), GFP_KERNEL);
1080 	if (!priv){
1081 		err("%s- kmalloc(%Zd) failed.", __FUNCTION__, sizeof(struct ftdi_private));
1082 		return -ENOMEM;
1083 	}
1084 	memset(priv, 0, sizeof(*priv));
1085 
1086 	spin_lock_init(&priv->rx_lock);
1087         init_waitqueue_head(&priv->delta_msr_wait);
1088 	/* This will push the characters through immediately rather
1089 	   than queue a task to deliver them */
1090 	priv->flags = ASYNC_LOW_LATENCY;
1091 
1092 	/* Increase the size of read buffers */
1093 	kfree(port->bulk_in_buffer);
1094 	port->bulk_in_buffer = kmalloc (BUFSZ, GFP_KERNEL);
1095 	if (!port->bulk_in_buffer) {
1096 		kfree (priv);
1097 		return -ENOMEM;
1098 	}
1099 	if (port->read_urb) {
1100 		port->read_urb->transfer_buffer = port->bulk_in_buffer;
1101 		port->read_urb->transfer_buffer_length = BUFSZ;
1102 	}
1103 
1104 	INIT_WORK(&priv->rx_work, ftdi_process_read, port);
1105 
1106 	/* Free port's existing write urb and transfer buffer. */
1107 	if (port->write_urb) {
1108 		usb_free_urb (port->write_urb);
1109 		port->write_urb = NULL;
1110 	}
1111 	kfree(port->bulk_out_buffer);
1112 	port->bulk_out_buffer = NULL;
1113 
1114 	usb_set_serial_port_data(serial->port[0], priv);
1115 
1116 	ftdi_determine_type (serial->port[0]);
1117 	create_sysfs_attrs(serial);
1118 
1119 	/* Check for device requiring special set up. */
1120 	quirk = (struct ftdi_sio_quirk *)usb_get_serial_data(serial);
1121 	if (quirk && quirk->setup) {
1122 		quirk->setup(serial);
1123 	}
1124 
1125 	return (0);
1126 } /* ftdi_sio_attach */
1127 
1128 
1129 /* Setup for the USB-UIRT device, which requires hardwired
1130  * baudrate (38400 gets mapped to 312500) */
1131 /* Called from usbserial:serial_probe */
1132 static void ftdi_USB_UIRT_setup (struct usb_serial *serial)
1133 {
1134 	struct ftdi_private *priv;
1135 
1136 	dbg("%s",__FUNCTION__);
1137 
1138 	priv = usb_get_serial_port_data(serial->port[0]);
1139 	priv->flags |= ASYNC_SPD_CUST;
1140 	priv->custom_divisor = 77;
1141 	priv->force_baud = B38400;
1142 } /* ftdi_USB_UIRT_setup */
1143 
1144 /* Setup for the HE-TIRA1 device, which requires hardwired
1145  * baudrate (38400 gets mapped to 100000) and RTS-CTS enabled.  */
1146 static void ftdi_HE_TIRA1_setup (struct usb_serial *serial)
1147 {
1148 	struct ftdi_private *priv;
1149 
1150 	dbg("%s",__FUNCTION__);
1151 
1152 	priv = usb_get_serial_port_data(serial->port[0]);
1153 	priv->flags |= ASYNC_SPD_CUST;
1154 	priv->custom_divisor = 240;
1155 	priv->force_baud = B38400;
1156 	priv->force_rtscts = 1;
1157 } /* ftdi_HE_TIRA1_setup */
1158 
1159 
1160 /* ftdi_shutdown is called from usbserial:usb_serial_disconnect
1161  *   it is called when the usb device is disconnected
1162  *
1163  *   usbserial:usb_serial_disconnect
1164  *      calls __serial_close for each open of the port
1165  *      shutdown is called then (ie ftdi_shutdown)
1166  */
1167 
1168 
1169 static void ftdi_shutdown (struct usb_serial *serial)
1170 { /* ftdi_shutdown */
1171 
1172 	struct usb_serial_port *port = serial->port[0];
1173 	struct ftdi_private *priv = usb_get_serial_port_data(port);
1174 
1175 	dbg("%s", __FUNCTION__);
1176 
1177 	remove_sysfs_attrs(serial);
1178 
1179 	/* all open ports are closed at this point
1180          *    (by usbserial.c:__serial_close, which calls ftdi_close)
1181 	 */
1182 
1183 	if (priv) {
1184 		usb_set_serial_port_data(port, NULL);
1185 		kfree(priv);
1186 	}
1187 } /* ftdi_shutdown */
1188 
1189 
1190 static int  ftdi_open (struct usb_serial_port *port, struct file *filp)
1191 { /* ftdi_open */
1192 	struct termios tmp_termios;
1193 	struct usb_device *dev = port->serial->dev;
1194 	struct ftdi_private *priv = usb_get_serial_port_data(port);
1195 	unsigned long flags;
1196 
1197 	int result = 0;
1198 	char buf[1]; /* Needed for the usb_control_msg I think */
1199 
1200 	dbg("%s", __FUNCTION__);
1201 
1202 
1203 	port->tty->low_latency = (priv->flags & ASYNC_LOW_LATENCY) ? 1 : 0;
1204 
1205 	/* No error checking for this (will get errors later anyway) */
1206 	/* See ftdi_sio.h for description of what is reset */
1207 	usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
1208 			FTDI_SIO_RESET_REQUEST, FTDI_SIO_RESET_REQUEST_TYPE,
1209 			FTDI_SIO_RESET_SIO,
1210 			priv->interface, buf, 0, WDR_TIMEOUT);
1211 
1212 	/* Termios defaults are set by usb_serial_init. We don't change
1213 	   port->tty->termios - this would loose speed settings, etc.
1214 	   This is same behaviour as serial.c/rs_open() - Kuba */
1215 
1216 	/* ftdi_set_termios  will send usb control messages */
1217 	ftdi_set_termios(port, &tmp_termios);
1218 
1219 	/* FIXME: Flow control might be enabled, so it should be checked -
1220 	   we have no control of defaults! */
1221 	/* Turn on RTS and DTR since we are not flow controlling by default */
1222 	if (set_dtr(port, HIGH) < 0) {
1223 		err("%s Error from DTR HIGH urb", __FUNCTION__);
1224 	}
1225 	if (set_rts(port, HIGH) < 0){
1226 		err("%s Error from RTS HIGH urb", __FUNCTION__);
1227 	}
1228 
1229 	/* Not throttled */
1230 	spin_lock_irqsave(&priv->rx_lock, flags);
1231 	priv->rx_flags &= ~(THROTTLED | ACTUALLY_THROTTLED);
1232 	spin_unlock_irqrestore(&priv->rx_lock, flags);
1233 
1234 	/* Start reading from the device */
1235 	priv->rx_processed = 0;
1236 	usb_fill_bulk_urb(port->read_urb, dev,
1237 		      usb_rcvbulkpipe(dev, port->bulk_in_endpointAddress),
1238 		      port->read_urb->transfer_buffer, port->read_urb->transfer_buffer_length,
1239 		      ftdi_read_bulk_callback, port);
1240 	result = usb_submit_urb(port->read_urb, GFP_KERNEL);
1241 	if (result)
1242 		err("%s - failed submitting read urb, error %d", __FUNCTION__, result);
1243 
1244 
1245 	return result;
1246 } /* ftdi_open */
1247 
1248 
1249 
1250 /*
1251  * usbserial:__serial_close  only calls ftdi_close if the point is open
1252  *
1253  *   This only gets called when it is the last close
1254  *
1255  *
1256  */
1257 
1258 static void ftdi_close (struct usb_serial_port *port, struct file *filp)
1259 { /* ftdi_close */
1260 	unsigned int c_cflag = port->tty->termios->c_cflag;
1261 	struct ftdi_private *priv = usb_get_serial_port_data(port);
1262 	char buf[1];
1263 
1264 	dbg("%s", __FUNCTION__);
1265 
1266 	if (c_cflag & HUPCL){
1267 		/* Disable flow control */
1268 		if (usb_control_msg(port->serial->dev,
1269 				    usb_sndctrlpipe(port->serial->dev, 0),
1270 				    FTDI_SIO_SET_FLOW_CTRL_REQUEST,
1271 				    FTDI_SIO_SET_FLOW_CTRL_REQUEST_TYPE,
1272 				    0, priv->interface, buf, 0,
1273 				    WDR_TIMEOUT) < 0) {
1274 			err("error from flowcontrol urb");
1275 		}
1276 
1277 		/* drop DTR */
1278 		if (set_dtr(port, LOW) < 0){
1279 			err("Error from DTR LOW urb");
1280 		}
1281 		/* drop RTS */
1282 		if (set_rts(port, LOW) < 0) {
1283 			err("Error from RTS LOW urb");
1284 		}
1285 	} /* Note change no line if hupcl is off */
1286 
1287 	/* cancel any scheduled reading */
1288 	cancel_delayed_work(&priv->rx_work);
1289 	flush_scheduled_work();
1290 
1291 	/* shutdown our bulk read */
1292 	if (port->read_urb)
1293 		usb_kill_urb(port->read_urb);
1294 } /* ftdi_close */
1295 
1296 
1297 
1298 /* The SIO requires the first byte to have:
1299  *  B0 1
1300  *  B1 0
1301  *  B2..7 length of message excluding byte 0
1302  *
1303  * The new devices do not require this byte
1304  */
1305 static int ftdi_write (struct usb_serial_port *port,
1306 			   const unsigned char *buf, int count)
1307 { /* ftdi_write */
1308 	struct ftdi_private *priv = usb_get_serial_port_data(port);
1309 	struct urb *urb;
1310 	unsigned char *buffer;
1311 	int data_offset ;       /* will be 1 for the SIO and 0 otherwise */
1312 	int status;
1313 	int transfer_size;
1314 
1315 	dbg("%s port %d, %d bytes", __FUNCTION__, port->number, count);
1316 
1317 	if (count == 0) {
1318 		dbg("write request of 0 bytes");
1319 		return 0;
1320 	}
1321 
1322 	data_offset = priv->write_offset;
1323         dbg("data_offset set to %d",data_offset);
1324 
1325 	/* Determine total transfer size */
1326 	transfer_size = count;
1327 	if (data_offset > 0) {
1328 		/* Original sio needs control bytes too... */
1329 		transfer_size += (data_offset *
1330 				((count + (PKTSZ - 1 - data_offset)) /
1331 				 (PKTSZ - data_offset)));
1332 	}
1333 
1334 	buffer = kmalloc (transfer_size, GFP_ATOMIC);
1335 	if (!buffer) {
1336 		err("%s ran out of kernel memory for urb ...", __FUNCTION__);
1337 		return -ENOMEM;
1338 	}
1339 
1340 	urb = usb_alloc_urb(0, GFP_ATOMIC);
1341 	if (!urb) {
1342 		err("%s - no more free urbs", __FUNCTION__);
1343 		kfree (buffer);
1344 		return -ENOMEM;
1345 	}
1346 
1347 	/* Copy data */
1348 	if (data_offset > 0) {
1349 		/* Original sio requires control byte at start of each packet. */
1350 		int user_pktsz = PKTSZ - data_offset;
1351 		int todo = count;
1352 		unsigned char *first_byte = buffer;
1353 		const unsigned char *current_position = buf;
1354 
1355 		while (todo > 0) {
1356 			if (user_pktsz > todo) {
1357 				user_pktsz = todo;
1358 			}
1359 			/* Write the control byte at the front of the packet*/
1360 			*first_byte = 1 | ((user_pktsz) << 2);
1361 			/* Copy data for packet */
1362 			memcpy (first_byte + data_offset,
1363 				current_position, user_pktsz);
1364 			first_byte += user_pktsz + data_offset;
1365 			current_position += user_pktsz;
1366 			todo -= user_pktsz;
1367 		}
1368 	} else {
1369 		/* No control byte required. */
1370 		/* Copy in the data to send */
1371 		memcpy (buffer, buf, count);
1372 	}
1373 
1374 	usb_serial_debug_data(debug, &port->dev, __FUNCTION__, transfer_size, buffer);
1375 
1376 	/* fill the buffer and send it */
1377 	usb_fill_bulk_urb(urb, port->serial->dev,
1378 		      usb_sndbulkpipe(port->serial->dev, port->bulk_out_endpointAddress),
1379 		      buffer, transfer_size,
1380 		      ftdi_write_bulk_callback, port);
1381 
1382 	status = usb_submit_urb(urb, GFP_ATOMIC);
1383 	if (status) {
1384 		err("%s - failed submitting write urb, error %d", __FUNCTION__, status);
1385 		count = status;
1386 		kfree (buffer);
1387 	}
1388 
1389 	/* we are done with this urb, so let the host driver
1390 	 * really free it when it is finished with it */
1391 	usb_free_urb (urb);
1392 
1393 	dbg("%s write returning: %d", __FUNCTION__, count);
1394 	return count;
1395 } /* ftdi_write */
1396 
1397 
1398 /* This function may get called when the device is closed */
1399 
1400 static void ftdi_write_bulk_callback (struct urb *urb, struct pt_regs *regs)
1401 {
1402 	struct usb_serial_port *port = (struct usb_serial_port *)urb->context;
1403 
1404 	/* free up the transfer buffer, as usb_free_urb() does not do this */
1405 	kfree (urb->transfer_buffer);
1406 
1407 	dbg("%s - port %d", __FUNCTION__, port->number);
1408 
1409 	if (urb->status) {
1410 		dbg("nonzero write bulk status received: %d", urb->status);
1411 		return;
1412 	}
1413 
1414 	schedule_work(&port->work);
1415 } /* ftdi_write_bulk_callback */
1416 
1417 
1418 static int ftdi_write_room( struct usb_serial_port *port )
1419 {
1420 	dbg("%s - port %d", __FUNCTION__, port->number);
1421 
1422 	/*
1423 	 * We really can take anything the user throws at us
1424 	 * but let's pick a nice big number to tell the tty
1425 	 * layer that we have lots of free space
1426 	 */
1427 	return 2048;
1428 } /* ftdi_write_room */
1429 
1430 
1431 static int ftdi_chars_in_buffer (struct usb_serial_port *port)
1432 { /* ftdi_chars_in_buffer */
1433 	dbg("%s - port %d", __FUNCTION__, port->number);
1434 
1435 	/*
1436 	 * We can't really account for how much data we
1437 	 * have sent out, but hasn't made it through to the
1438 	 * device, so just tell the tty layer that everything
1439 	 * is flushed.
1440 	 */
1441 	return 0;
1442 } /* ftdi_chars_in_buffer */
1443 
1444 
1445 
1446 static void ftdi_read_bulk_callback (struct urb *urb, struct pt_regs *regs)
1447 { /* ftdi_read_bulk_callback */
1448 	struct usb_serial_port *port = (struct usb_serial_port *)urb->context;
1449 	struct tty_struct *tty;
1450 	struct ftdi_private *priv;
1451 
1452 	if (urb->number_of_packets > 0) {
1453 		err("%s transfer_buffer_length %d actual_length %d number of packets %d",__FUNCTION__,
1454 		    urb->transfer_buffer_length, urb->actual_length, urb->number_of_packets );
1455 		err("%s transfer_flags %x ", __FUNCTION__,urb->transfer_flags );
1456 	}
1457 
1458 	dbg("%s - port %d", __FUNCTION__, port->number);
1459 
1460 	if (port->open_count <= 0)
1461 		return;
1462 
1463 	tty = port->tty;
1464 	if (!tty) {
1465 		dbg("%s - bad tty pointer - exiting",__FUNCTION__);
1466 		return;
1467 	}
1468 
1469 	priv = usb_get_serial_port_data(port);
1470 	if (!priv) {
1471 		dbg("%s - bad port private data pointer - exiting", __FUNCTION__);
1472 		return;
1473 	}
1474 
1475 	if (urb != port->read_urb) {
1476 		err("%s - Not my urb!", __FUNCTION__);
1477 	}
1478 
1479 	if (urb->status) {
1480 		/* This will happen at close every time so it is a dbg not an err */
1481 		dbg("(this is ok on close) nonzero read bulk status received: %d", urb->status);
1482 		return;
1483 	}
1484 
1485 	ftdi_process_read(port);
1486 
1487 } /* ftdi_read_bulk_callback */
1488 
1489 
1490 static void ftdi_process_read (void *param)
1491 { /* ftdi_process_read */
1492 	struct usb_serial_port *port = (struct usb_serial_port*)param;
1493 	struct urb *urb;
1494 	struct tty_struct *tty;
1495 	struct ftdi_private *priv;
1496 	char error_flag;
1497        	unsigned char *data;
1498 
1499 	int i;
1500 	int result;
1501 	int need_flip;
1502 	int packet_offset;
1503 	unsigned long flags;
1504 
1505 	dbg("%s - port %d", __FUNCTION__, port->number);
1506 
1507 	if (port->open_count <= 0)
1508 		return;
1509 
1510 	tty = port->tty;
1511 	if (!tty) {
1512 		dbg("%s - bad tty pointer - exiting",__FUNCTION__);
1513 		return;
1514 	}
1515 
1516 	priv = usb_get_serial_port_data(port);
1517 	if (!priv) {
1518 		dbg("%s - bad port private data pointer - exiting", __FUNCTION__);
1519 		return;
1520 	}
1521 
1522 	urb = port->read_urb;
1523 	if (!urb) {
1524 		dbg("%s - bad read_urb pointer - exiting", __FUNCTION__);
1525 		return;
1526 	}
1527 
1528 	data = urb->transfer_buffer;
1529 
1530 	if (priv->rx_processed) {
1531 		dbg("%s - already processed: %d bytes, %d remain", __FUNCTION__,
1532 				priv->rx_processed,
1533 				urb->actual_length - priv->rx_processed);
1534 	} else {
1535 		/* The first two bytes of every read packet are status */
1536 		if (urb->actual_length > 2) {
1537 			usb_serial_debug_data(debug, &port->dev, __FUNCTION__, urb->actual_length, data);
1538 		} else {
1539 			dbg("Status only: %03oo %03oo",data[0],data[1]);
1540 		}
1541 	}
1542 
1543 
1544 	/* TO DO -- check for hung up line and handle appropriately: */
1545 	/*   send hangup  */
1546 	/* See acm.c - you do a tty_hangup  - eg tty_hangup(tty) */
1547 	/* if CD is dropped and the line is not CLOCAL then we should hangup */
1548 
1549 	need_flip = 0;
1550 	for (packet_offset = priv->rx_processed; packet_offset < urb->actual_length; packet_offset += PKTSZ) {
1551 		int length;
1552 
1553 		/* Compare new line status to the old one, signal if different */
1554 		/* N.B. packet may be processed more than once, but differences
1555 		 * are only processed once.  */
1556 		if (priv != NULL) {
1557 			char new_status = data[packet_offset+0] & FTDI_STATUS_B0_MASK;
1558 			if (new_status != priv->prev_status) {
1559 				priv->diff_status |= new_status ^ priv->prev_status;
1560 				wake_up_interruptible(&priv->delta_msr_wait);
1561 				priv->prev_status = new_status;
1562 			}
1563 		}
1564 
1565 		length = min(PKTSZ, urb->actual_length-packet_offset)-2;
1566 		if (length < 0) {
1567 			err("%s - bad packet length: %d", __FUNCTION__, length+2);
1568 			length = 0;
1569 		}
1570 
1571 		/* have to make sure we don't overflow the buffer
1572 		   with tty_insert_flip_char's */
1573 		if (tty->flip.count+length > TTY_FLIPBUF_SIZE) {
1574 			tty_flip_buffer_push(tty);
1575 			need_flip = 0;
1576 
1577 			if (tty->flip.count != 0) {
1578 				/* flip didn't work, this happens when ftdi_process_read() is
1579 				 * called from ftdi_unthrottle, because TTY_DONT_FLIP is set */
1580 				dbg("%s - flip buffer push failed", __FUNCTION__);
1581 				break;
1582 			}
1583 		}
1584 		if (priv->rx_flags & THROTTLED) {
1585 			dbg("%s - throttled", __FUNCTION__);
1586 			break;
1587 		}
1588 		if (tty->ldisc.receive_room(tty)-tty->flip.count < length) {
1589 			/* break out & wait for throttling/unthrottling to happen */
1590 			dbg("%s - receive room low", __FUNCTION__);
1591 			break;
1592 		}
1593 
1594 		/* Handle errors and break */
1595 		error_flag = TTY_NORMAL;
1596 		/* Although the device uses a bitmask and hence can have multiple */
1597 		/* errors on a packet - the order here sets the priority the */
1598 		/* error is returned to the tty layer  */
1599 
1600 		if ( data[packet_offset+1] & FTDI_RS_OE ) {
1601 			error_flag = TTY_OVERRUN;
1602 			dbg("OVERRRUN error");
1603 		}
1604 		if ( data[packet_offset+1] & FTDI_RS_BI ) {
1605 			error_flag = TTY_BREAK;
1606 			dbg("BREAK received");
1607 		}
1608 		if ( data[packet_offset+1] & FTDI_RS_PE ) {
1609 			error_flag = TTY_PARITY;
1610 			dbg("PARITY error");
1611 		}
1612 		if ( data[packet_offset+1] & FTDI_RS_FE ) {
1613 			error_flag = TTY_FRAME;
1614 			dbg("FRAMING error");
1615 		}
1616 		if (length > 0) {
1617 			for (i = 2; i < length+2; i++) {
1618 				/* Note that the error flag is duplicated for
1619 				   every character received since we don't know
1620 				   which character it applied to */
1621 				tty_insert_flip_char(tty, data[packet_offset+i], error_flag);
1622 			}
1623 			need_flip = 1;
1624 		}
1625 
1626 #ifdef NOT_CORRECT_BUT_KEEPING_IT_FOR_NOW
1627 		/* if a parity error is detected you get status packets forever
1628 		   until a character is sent without a parity error.
1629 		   This doesn't work well since the application receives a never
1630 		   ending stream of bad data - even though new data hasn't been sent.
1631 		   Therefore I (bill) have taken this out.
1632 		   However - this might make sense for framing errors and so on
1633 		   so I am leaving the code in for now.
1634 		*/
1635 		else {
1636 			if (error_flag != TTY_NORMAL){
1637 				dbg("error_flag is not normal");
1638 				/* In this case it is just status - if that is an error send a bad character */
1639 				if(tty->flip.count >= TTY_FLIPBUF_SIZE) {
1640 					tty_flip_buffer_push(tty);
1641 				}
1642 				tty_insert_flip_char(tty, 0xff, error_flag);
1643 				need_flip = 1;
1644 			}
1645 		}
1646 #endif
1647 	} /* "for(packet_offset=0..." */
1648 
1649 	/* Low latency */
1650 	if (need_flip) {
1651 		tty_flip_buffer_push(tty);
1652 	}
1653 
1654 	if (packet_offset < urb->actual_length) {
1655 		/* not completely processed - record progress */
1656 		priv->rx_processed = packet_offset;
1657 		dbg("%s - incomplete, %d bytes processed, %d remain",
1658 				__FUNCTION__, packet_offset,
1659 				urb->actual_length - packet_offset);
1660 		/* check if we were throttled while processing */
1661 		spin_lock_irqsave(&priv->rx_lock, flags);
1662 		if (priv->rx_flags & THROTTLED) {
1663 			priv->rx_flags |= ACTUALLY_THROTTLED;
1664 			spin_unlock_irqrestore(&priv->rx_lock, flags);
1665 			dbg("%s - deferring remainder until unthrottled",
1666 					__FUNCTION__);
1667 			return;
1668 		}
1669 		spin_unlock_irqrestore(&priv->rx_lock, flags);
1670 		/* if the port is closed stop trying to read */
1671 		if (port->open_count > 0){
1672 			/* delay processing of remainder */
1673 			schedule_delayed_work(&priv->rx_work, 1);
1674 		} else {
1675 			dbg("%s - port is closed", __FUNCTION__);
1676 		}
1677 		return;
1678 	}
1679 
1680 	/* urb is completely processed */
1681 	priv->rx_processed = 0;
1682 
1683 	/* if the port is closed stop trying to read */
1684 	if (port->open_count > 0){
1685 		/* Continue trying to always read  */
1686 		usb_fill_bulk_urb(port->read_urb, port->serial->dev,
1687 			      usb_rcvbulkpipe(port->serial->dev, port->bulk_in_endpointAddress),
1688 			      port->read_urb->transfer_buffer, port->read_urb->transfer_buffer_length,
1689 			      ftdi_read_bulk_callback, port);
1690 
1691 		result = usb_submit_urb(port->read_urb, GFP_ATOMIC);
1692 		if (result)
1693 			err("%s - failed resubmitting read urb, error %d", __FUNCTION__, result);
1694 	}
1695 
1696 	return;
1697 } /* ftdi_process_read */
1698 
1699 
1700 static void ftdi_break_ctl( struct usb_serial_port *port, int break_state )
1701 {
1702 	struct ftdi_private *priv = usb_get_serial_port_data(port);
1703 	__u16 urb_value = 0;
1704 	char buf[1];
1705 
1706 	/* break_state = -1 to turn on break, and 0 to turn off break */
1707 	/* see drivers/char/tty_io.c to see it used */
1708 	/* last_set_data_urb_value NEVER has the break bit set in it */
1709 
1710 	if (break_state) {
1711 		urb_value = priv->last_set_data_urb_value | FTDI_SIO_SET_BREAK;
1712 	} else {
1713 		urb_value = priv->last_set_data_urb_value;
1714 	}
1715 
1716 
1717 	if (usb_control_msg(port->serial->dev, usb_sndctrlpipe(port->serial->dev, 0),
1718 			    FTDI_SIO_SET_DATA_REQUEST,
1719 			    FTDI_SIO_SET_DATA_REQUEST_TYPE,
1720 			    urb_value , priv->interface,
1721 			    buf, 0, WDR_TIMEOUT) < 0) {
1722 		err("%s FAILED to enable/disable break state (state was %d)", __FUNCTION__,break_state);
1723 	}
1724 
1725 	dbg("%s break state is %d - urb is %d", __FUNCTION__,break_state, urb_value);
1726 
1727 }
1728 
1729 
1730 /* old_termios contains the original termios settings and tty->termios contains
1731  * the new setting to be used
1732  * WARNING: set_termios calls this with old_termios in kernel space
1733  */
1734 
1735 static void ftdi_set_termios (struct usb_serial_port *port, struct termios *old_termios)
1736 { /* ftdi_termios */
1737 	struct usb_device *dev = port->serial->dev;
1738 	unsigned int cflag = port->tty->termios->c_cflag;
1739 	struct ftdi_private *priv = usb_get_serial_port_data(port);
1740 	__u16 urb_value; /* will hold the new flags */
1741 	char buf[1]; /* Perhaps I should dynamically alloc this? */
1742 
1743 	// Added for xon/xoff support
1744 	unsigned int iflag = port->tty->termios->c_iflag;
1745 	unsigned char vstop;
1746 	unsigned char vstart;
1747 
1748 	dbg("%s", __FUNCTION__);
1749 
1750 	/* Force baud rate if this device requires it, unless it is set to B0. */
1751 	if (priv->force_baud && ((port->tty->termios->c_cflag & CBAUD) != B0)) {
1752 		dbg("%s: forcing baud rate for this device", __FUNCTION__);
1753 		port->tty->termios->c_cflag &= ~CBAUD;
1754 		port->tty->termios->c_cflag |= priv->force_baud;
1755 	}
1756 
1757 	/* Force RTS-CTS if this device requires it. */
1758 	if (priv->force_rtscts) {
1759 		dbg("%s: forcing rtscts for this device", __FUNCTION__);
1760 		port->tty->termios->c_cflag |= CRTSCTS;
1761 	}
1762 
1763 	cflag = port->tty->termios->c_cflag;
1764 
1765 	/* FIXME -For this cut I don't care if the line is really changing or
1766 	   not  - so just do the change regardless  - should be able to
1767 	   compare old_termios and tty->termios */
1768 	/* NOTE These routines can get interrupted by
1769 	   ftdi_sio_read_bulk_callback  - need to examine what this
1770            means - don't see any problems yet */
1771 
1772 	/* Set number of data bits, parity, stop bits */
1773 
1774 	urb_value = 0;
1775 	urb_value |= (cflag & CSTOPB ? FTDI_SIO_SET_DATA_STOP_BITS_2 :
1776 		      FTDI_SIO_SET_DATA_STOP_BITS_1);
1777 	urb_value |= (cflag & PARENB ?
1778 		      (cflag & PARODD ? FTDI_SIO_SET_DATA_PARITY_ODD :
1779 		       FTDI_SIO_SET_DATA_PARITY_EVEN) :
1780 		      FTDI_SIO_SET_DATA_PARITY_NONE);
1781 	if (cflag & CSIZE) {
1782 		switch (cflag & CSIZE) {
1783 		case CS5: urb_value |= 5; dbg("Setting CS5"); break;
1784 		case CS6: urb_value |= 6; dbg("Setting CS6"); break;
1785 		case CS7: urb_value |= 7; dbg("Setting CS7"); break;
1786 		case CS8: urb_value |= 8; dbg("Setting CS8"); break;
1787 		default:
1788 			err("CSIZE was set but not CS5-CS8");
1789 		}
1790 	}
1791 
1792 	/* This is needed by the break command since it uses the same command - but is
1793 	 *  or'ed with this value  */
1794 	priv->last_set_data_urb_value = urb_value;
1795 
1796 	if (usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
1797 			    FTDI_SIO_SET_DATA_REQUEST,
1798 			    FTDI_SIO_SET_DATA_REQUEST_TYPE,
1799 			    urb_value , priv->interface,
1800 			    buf, 0, 100) < 0) {
1801 		err("%s FAILED to set databits/stopbits/parity", __FUNCTION__);
1802 	}
1803 
1804 	/* Now do the baudrate */
1805 	if ((cflag & CBAUD) == B0 ) {
1806 		/* Disable flow control */
1807 		if (usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
1808 				    FTDI_SIO_SET_FLOW_CTRL_REQUEST,
1809 				    FTDI_SIO_SET_FLOW_CTRL_REQUEST_TYPE,
1810 				    0, priv->interface,
1811 				    buf, 0, WDR_TIMEOUT) < 0) {
1812 			err("%s error from disable flowcontrol urb", __FUNCTION__);
1813 		}
1814 		/* Drop RTS and DTR */
1815 		if (set_dtr(port, LOW) < 0){
1816 			err("%s Error from DTR LOW urb", __FUNCTION__);
1817 		}
1818 		if (set_rts(port, LOW) < 0){
1819 			err("%s Error from RTS LOW urb", __FUNCTION__);
1820 		}
1821 
1822 	} else {
1823 		/* set the baudrate determined before */
1824 		if (change_speed(port)) {
1825 			err("%s urb failed to set baurdrate", __FUNCTION__);
1826 		}
1827 		/* Ensure  RTS and DTR are raised */
1828 		else if (set_dtr(port, HIGH) < 0){
1829 			err("%s Error from DTR HIGH urb", __FUNCTION__);
1830 		}
1831 		else if (set_rts(port, HIGH) < 0){
1832 			err("%s Error from RTS HIGH urb", __FUNCTION__);
1833 		}
1834 	}
1835 
1836 	/* Set flow control */
1837 	/* Note device also supports DTR/CD (ugh) and Xon/Xoff in hardware */
1838 	if (cflag & CRTSCTS) {
1839 		dbg("%s Setting to CRTSCTS flow control", __FUNCTION__);
1840 		if (usb_control_msg(dev,
1841 				    usb_sndctrlpipe(dev, 0),
1842 				    FTDI_SIO_SET_FLOW_CTRL_REQUEST,
1843 				    FTDI_SIO_SET_FLOW_CTRL_REQUEST_TYPE,
1844 				    0 , (FTDI_SIO_RTS_CTS_HS | priv->interface),
1845 				    buf, 0, WDR_TIMEOUT) < 0) {
1846 			err("urb failed to set to rts/cts flow control");
1847 		}
1848 
1849 	} else {
1850 		/*
1851 		 * Xon/Xoff code
1852 		 *
1853 		 * Check the IXOFF status in the iflag component of the termios structure
1854 		 * if IXOFF is not set, the pre-xon/xoff code is executed.
1855 		*/
1856 		if (iflag & IXOFF) {
1857 			dbg("%s  request to enable xonxoff iflag=%04x",__FUNCTION__,iflag);
1858 			// Try to enable the XON/XOFF on the ftdi_sio
1859 			// Set the vstart and vstop -- could have been done up above where
1860 			// a lot of other dereferencing is done but that would be very
1861 			// inefficient as vstart and vstop are not always needed
1862 			vstart=port->tty->termios->c_cc[VSTART];
1863 			vstop=port->tty->termios->c_cc[VSTOP];
1864 			urb_value=(vstop << 8) | (vstart);
1865 
1866 			if (usb_control_msg(dev,
1867 					    usb_sndctrlpipe(dev, 0),
1868 					    FTDI_SIO_SET_FLOW_CTRL_REQUEST,
1869 					    FTDI_SIO_SET_FLOW_CTRL_REQUEST_TYPE,
1870 					    urb_value , (FTDI_SIO_XON_XOFF_HS
1871 							 | priv->interface),
1872 					    buf, 0, WDR_TIMEOUT) < 0) {
1873 				err("urb failed to set to xon/xoff flow control");
1874 			}
1875 		} else {
1876 			/* else clause to only run if cfag ! CRTSCTS and iflag ! XOFF */
1877 			/* CHECKME Assuming XON/XOFF handled by tty stack - not by device */
1878 			dbg("%s Turning off hardware flow control", __FUNCTION__);
1879 			if (usb_control_msg(dev,
1880 					    usb_sndctrlpipe(dev, 0),
1881 					    FTDI_SIO_SET_FLOW_CTRL_REQUEST,
1882 					    FTDI_SIO_SET_FLOW_CTRL_REQUEST_TYPE,
1883 					    0, priv->interface,
1884 					    buf, 0, WDR_TIMEOUT) < 0) {
1885 				err("urb failed to clear flow control");
1886 			}
1887 		}
1888 
1889 	}
1890 	return;
1891 } /* ftdi_termios */
1892 
1893 
1894 static int ftdi_tiocmget (struct usb_serial_port *port, struct file *file)
1895 {
1896 	struct ftdi_private *priv = usb_get_serial_port_data(port);
1897 	unsigned char buf[2];
1898 	int ret;
1899 
1900 	dbg("%s TIOCMGET", __FUNCTION__);
1901 	switch (priv->chip_type) {
1902 	case SIO:
1903 		/* Request the status from the device */
1904 		if ((ret = usb_control_msg(port->serial->dev,
1905 					   usb_rcvctrlpipe(port->serial->dev, 0),
1906 					   FTDI_SIO_GET_MODEM_STATUS_REQUEST,
1907 					   FTDI_SIO_GET_MODEM_STATUS_REQUEST_TYPE,
1908 					   0, 0,
1909 					   buf, 1, WDR_TIMEOUT)) < 0 ) {
1910 			err("%s Could not get modem status of device - err: %d", __FUNCTION__,
1911 			    ret);
1912 			return(ret);
1913 		}
1914 		break;
1915 	case FT8U232AM:
1916 	case FT232BM:
1917 	case FT2232C:
1918 		/* the 8U232AM returns a two byte value (the sio is a 1 byte value) - in the same
1919 		   format as the data returned from the in point */
1920 		if ((ret = usb_control_msg(port->serial->dev,
1921 					   usb_rcvctrlpipe(port->serial->dev, 0),
1922 					   FTDI_SIO_GET_MODEM_STATUS_REQUEST,
1923 					   FTDI_SIO_GET_MODEM_STATUS_REQUEST_TYPE,
1924 					   0, priv->interface,
1925 					   buf, 2, WDR_TIMEOUT)) < 0 ) {
1926 			err("%s Could not get modem status of device - err: %d", __FUNCTION__,
1927 			    ret);
1928 			return(ret);
1929 		}
1930 		break;
1931 	default:
1932 		return -EFAULT;
1933 		break;
1934 	}
1935 
1936 	return  (buf[0] & FTDI_SIO_DSR_MASK ? TIOCM_DSR : 0) |
1937 		(buf[0] & FTDI_SIO_CTS_MASK ? TIOCM_CTS : 0) |
1938 		(buf[0]  & FTDI_SIO_RI_MASK  ? TIOCM_RI  : 0) |
1939 		(buf[0]  & FTDI_SIO_RLSD_MASK ? TIOCM_CD  : 0) |
1940 		priv->last_dtr_rts;
1941 }
1942 
1943 static int ftdi_tiocmset(struct usb_serial_port *port, struct file * file, unsigned int set, unsigned int clear)
1944 {
1945 	int ret;
1946 
1947 	dbg("%s TIOCMSET", __FUNCTION__);
1948 	if (set & TIOCM_DTR){
1949 		if ((ret = set_dtr(port, HIGH)) < 0) {
1950 			err("Urb to set DTR failed");
1951 			return(ret);
1952 		}
1953 	}
1954 	if (set & TIOCM_RTS) {
1955 		if ((ret = set_rts(port, HIGH)) < 0){
1956 			err("Urb to set RTS failed");
1957 			return(ret);
1958 		}
1959 	}
1960 
1961 	if (clear & TIOCM_DTR){
1962 		if ((ret = set_dtr(port, LOW)) < 0){
1963 			err("Urb to unset DTR failed");
1964 			return(ret);
1965 		}
1966 	}
1967 	if (clear & TIOCM_RTS) {
1968 		if ((ret = set_rts(port, LOW)) < 0){
1969 			err("Urb to unset RTS failed");
1970 			return(ret);
1971 		}
1972 	}
1973 	return(0);
1974 }
1975 
1976 
1977 static int ftdi_ioctl (struct usb_serial_port *port, struct file * file, unsigned int cmd, unsigned long arg)
1978 {
1979 	struct ftdi_private *priv = usb_get_serial_port_data(port);
1980 
1981 	dbg("%s cmd 0x%04x", __FUNCTION__, cmd);
1982 
1983 	/* Based on code from acm.c and others */
1984 	switch (cmd) {
1985 
1986 	case TIOCGSERIAL: /* gets serial port data */
1987 		return get_serial_info(port, (struct serial_struct __user *) arg);
1988 
1989 	case TIOCSSERIAL: /* sets serial port data */
1990 		return set_serial_info(port, (struct serial_struct __user *) arg);
1991 
1992 	/*
1993 	 * Wait for any of the 4 modem inputs (DCD,RI,DSR,CTS) to change
1994 	 * - mask passed in arg for lines of interest
1995 	 *   (use |'ed TIOCM_RNG/DSR/CD/CTS for masking)
1996 	 * Caller should use TIOCGICOUNT to see which one it was.
1997 	 *
1998 	 * This code is borrowed from linux/drivers/char/serial.c
1999 	 */
2000 	case TIOCMIWAIT:
2001 		while (priv != NULL) {
2002 			interruptible_sleep_on(&priv->delta_msr_wait);
2003 			/* see if a signal did it */
2004 			if (signal_pending(current))
2005 				return -ERESTARTSYS;
2006 			else {
2007 				char diff = priv->diff_status;
2008 
2009 				if (diff == 0) {
2010 					return -EIO; /* no change => error */
2011 				}
2012 
2013 				/* Consume all events */
2014 				priv->diff_status = 0;
2015 
2016 				/* Return 0 if caller wanted to know about these bits */
2017 				if ( ((arg & TIOCM_RNG) && (diff & FTDI_RS0_RI)) ||
2018 				     ((arg & TIOCM_DSR) && (diff & FTDI_RS0_DSR)) ||
2019 				     ((arg & TIOCM_CD)  && (diff & FTDI_RS0_RLSD)) ||
2020 				     ((arg & TIOCM_CTS) && (diff & FTDI_RS0_CTS)) ) {
2021 					return 0;
2022 				}
2023 				/*
2024 				 * Otherwise caller can't care less about what happened,
2025 				 * and so we continue to wait for more events.
2026 				 */
2027 			}
2028 		}
2029 		return(0);
2030 		break;
2031 	default:
2032 		break;
2033 
2034 	}
2035 
2036 
2037 	/* This is not necessarily an error - turns out the higher layers will do
2038 	 *  some ioctls itself (see comment above)
2039 	 */
2040 	dbg("%s arg not supported - it was 0x%04x - check /usr/include/asm/ioctls.h", __FUNCTION__, cmd);
2041 
2042 	return(-ENOIOCTLCMD);
2043 } /* ftdi_ioctl */
2044 
2045 
2046 static void ftdi_throttle (struct usb_serial_port *port)
2047 {
2048 	struct ftdi_private *priv = usb_get_serial_port_data(port);
2049 	unsigned long flags;
2050 
2051 	dbg("%s - port %d", __FUNCTION__, port->number);
2052 
2053 	spin_lock_irqsave(&priv->rx_lock, flags);
2054 	priv->rx_flags |= THROTTLED;
2055 	spin_unlock_irqrestore(&priv->rx_lock, flags);
2056 }
2057 
2058 
2059 static void ftdi_unthrottle (struct usb_serial_port *port)
2060 {
2061 	struct ftdi_private *priv = usb_get_serial_port_data(port);
2062 	int actually_throttled;
2063 	unsigned long flags;
2064 
2065 	dbg("%s - port %d", __FUNCTION__, port->number);
2066 
2067 	spin_lock_irqsave(&priv->rx_lock, flags);
2068 	actually_throttled = priv->rx_flags & ACTUALLY_THROTTLED;
2069 	priv->rx_flags &= ~(THROTTLED | ACTUALLY_THROTTLED);
2070 	spin_unlock_irqrestore(&priv->rx_lock, flags);
2071 
2072 	if (actually_throttled)
2073 		schedule_work(&priv->rx_work);
2074 }
2075 
2076 static int __init ftdi_init (void)
2077 {
2078 	int retval;
2079 
2080 	dbg("%s", __FUNCTION__);
2081 	retval = usb_serial_register(&ftdi_sio_device);
2082 	if (retval)
2083 		goto failed_sio_register;
2084 	retval = usb_register(&ftdi_driver);
2085 	if (retval)
2086 		goto failed_usb_register;
2087 
2088 	info(DRIVER_VERSION ":" DRIVER_DESC);
2089 	return 0;
2090 failed_usb_register:
2091 	usb_serial_deregister(&ftdi_sio_device);
2092 failed_sio_register:
2093 	return retval;
2094 }
2095 
2096 
2097 static void __exit ftdi_exit (void)
2098 {
2099 
2100 	dbg("%s", __FUNCTION__);
2101 
2102 	usb_deregister (&ftdi_driver);
2103 	usb_serial_deregister (&ftdi_sio_device);
2104 
2105 }
2106 
2107 
2108 module_init(ftdi_init);
2109 module_exit(ftdi_exit);
2110 
2111 MODULE_AUTHOR( DRIVER_AUTHOR );
2112 MODULE_DESCRIPTION( DRIVER_DESC );
2113 MODULE_LICENSE("GPL");
2114 
2115 module_param(debug, bool, S_IRUGO | S_IWUSR);
2116 MODULE_PARM_DESC(debug, "Debug enabled or not");
2117 
2118