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-rw-r--r--drivers/usb/serial/digi_acceleport.c216
1 files changed, 0 insertions, 216 deletions
diff --git a/drivers/usb/serial/digi_acceleport.c b/drivers/usb/serial/digi_acceleport.c
index e92cbefc0f88..3786e9544ae0 100644
--- a/drivers/usb/serial/digi_acceleport.c
+++ b/drivers/usb/serial/digi_acceleport.c
@@ -13,222 +13,6 @@
13* 13*
14* Peter Berger (pberger@brimson.com) 14* Peter Berger (pberger@brimson.com)
15* Al Borchers (borchers@steinerpoint.com) 15* Al Borchers (borchers@steinerpoint.com)
16*
17* (12/03/2001) gkh
18* switched to using port->port.count instead of private version.
19* Removed port->active
20*
21* (04/08/2001) gb
22* Identify version on module load.
23*
24* (11/01/2000) Adam J. Richter
25* usb_device_id table support
26*
27* (11/01/2000) pberger and borchers
28* -- Turned off the USB_DISABLE_SPD flag for write bulk urbs--it caused
29* USB 4 ports to hang on startup.
30* -- Serialized access to write urbs by adding the dp_write_urb_in_use
31* flag; otherwise, the driver caused SMP system hangs. Watching the
32* urb status is not sufficient.
33*
34* (10/05/2000) gkh
35* -- Fixed bug with urb->dev not being set properly, now that the usb
36* core needs it.
37*
38* (8/8/2000) pberger and borchers
39* -- Fixed close so that
40* - it can timeout while waiting for transmit idle, if needed;
41* - it ignores interrupts when flushing the port, turning
42* of modem signalling, and so on;
43* - it waits for the flush to really complete before returning.
44* -- Read_bulk_callback and write_bulk_callback check for a closed
45* port before using the tty struct or writing to the port.
46* -- The two changes above fix the oops caused by interrupted closes.
47* -- Added interruptible args to write_oob_command and set_modem_signals
48* and added a timeout arg to transmit_idle; needed for fixes to
49* close.
50* -- Added code for rx_throttle and rx_unthrottle so that input flow
51* control works.
52* -- Added code to set overrun, parity, framing, and break errors
53* (untested).
54* -- Set USB_DISABLE_SPD flag for write bulk urbs, so no 0 length
55* bulk writes are done. These hung the Digi USB device. The
56* 0 length bulk writes were a new feature of usb-uhci added in
57* the 2.4.0-test6 kernels.
58* -- Fixed mod inc race in open; do mod inc before sleeping to wait
59* for a close to finish.
60*
61* (7/31/2000) pberger
62* -- Fixed bugs with hardware handshaking:
63* - Added code to set/clear tty->hw_stopped in digi_read_oob_callback()
64* and digi_set_termios()
65* -- Added code in digi_set_termios() to
66* - add conditional in code handling transition from B0 to only
67* set RTS if RTS/CTS flow control is either not in use or if
68* the port is not currently throttled.
69* - handle turning off CRTSCTS.
70*
71* (7/30/2000) borchers
72* -- Added support for more than one Digi USB device by moving
73* globals to a private structure in the pointed to from the
74* usb_serial structure.
75* -- Moved the modem change and transmit idle wait queues into
76* the port private structure, so each port has its own queue
77* rather than sharing global queues.
78* -- Added support for break signals.
79*
80* (7/25/2000) pberger
81* -- Added USB-2 support. Note: the USB-2 supports 3 devices: two
82* serial and a parallel port. The parallel port is implemented
83* as a serial-to-parallel converter. That is, the driver actually
84* presents all three USB-2 interfaces as serial ports, but the third
85* one physically connects to a parallel device. Thus, for example,
86* one could plug a parallel printer into the USB-2's third port,
87* but from the kernel's (and userland's) point of view what's
88* actually out there is a serial device.
89*
90* (7/15/2000) borchers
91* -- Fixed race in open when a close is in progress.
92* -- Keep count of opens and dec the module use count for each
93* outstanding open when shutdown is called (on disconnect).
94* -- Fixed sanity checks in read_bulk_callback and write_bulk_callback
95* so pointers are checked before use.
96* -- Split read bulk callback into in band and out of band
97* callbacks, and no longer restart read chains if there is
98* a status error or a sanity error. This fixed the seg
99* faults and other errors we used to get on disconnect.
100* -- Port->active is once again a flag as usb-serial intended it
101* to be, not a count. Since it was only a char it would
102* have been limited to 256 simultaneous opens. Now the open
103* count is kept in the port private structure in dp_open_count.
104* -- Added code for modularization of the digi_acceleport driver.
105*
106* (6/27/2000) pberger and borchers
107* -- Zeroed out sync field in the wakeup_task before first use;
108* otherwise the uninitialized value might prevent the task from
109* being scheduled.
110* -- Initialized ret value to 0 in write_bulk_callback, otherwise
111* the uninitialized value could cause a spurious debugging message.
112*
113* (6/22/2000) pberger and borchers
114* -- Made cond_wait_... inline--apparently on SPARC the flags arg
115* to spin_lock_irqsave cannot be passed to another function
116* to call spin_unlock_irqrestore. Thanks to Pauline Middelink.
117* -- In digi_set_modem_signals the inner nested spin locks use just
118* spin_lock() rather than spin_lock_irqsave(). The old code
119* mistakenly left interrupts off. Thanks to Pauline Middelink.
120* -- copy_from_user (which can sleep) is no longer called while a
121* spinlock is held. We copy to a local buffer before getting
122* the spinlock--don't like the extra copy but the code is simpler.
123* -- Printk and dbg are no longer called while a spin lock is held.
124*
125* (6/4/2000) pberger and borchers
126* -- Replaced separate calls to spin_unlock_irqrestore and
127* interruptible_sleep_on_timeout with a new function
128* cond_wait_interruptible_timeout_irqrestore. This eliminates
129* the race condition where the wake up could happen after
130* the unlock and before the sleep.
131* -- Close now waits for output to drain.
132* -- Open waits until any close in progress is finished.
133* -- All out of band responses are now processed, not just the
134* first in a USB packet.
135* -- Fixed a bug that prevented the driver from working when the
136* first Digi port was not the first USB serial port--the driver
137* was mistakenly using the external USB serial port number to
138* try to index into its internal ports.
139* -- Fixed an SMP bug -- write_bulk_callback is called directly from
140* an interrupt, so spin_lock_irqsave/spin_unlock_irqrestore are
141* needed for locks outside write_bulk_callback that are also
142* acquired by write_bulk_callback to prevent deadlocks.
143* -- Fixed support for select() by making digi_chars_in_buffer()
144* return 256 when -EINPROGRESS is set, as the line discipline
145* code in n_tty.c expects.
146* -- Fixed an include file ordering problem that prevented debugging
147* messages from working.
148* -- Fixed an intermittent timeout problem that caused writes to
149* sometimes get stuck on some machines on some kernels. It turns
150* out in these circumstances write_chan() (in n_tty.c) was
151* asleep waiting for our wakeup call. Even though we call
152* wake_up_interruptible() in digi_write_bulk_callback(), there is
153* a race condition that could cause the wakeup to fail: if our
154* wake_up_interruptible() call occurs between the time that our
155* driver write routine finishes and write_chan() sets current->state
156* to TASK_INTERRUPTIBLE, the effect of our wakeup setting the state
157* to TASK_RUNNING will be lost and write_chan's subsequent call to
158* schedule() will never return (unless it catches a signal).
159* This race condition occurs because write_bulk_callback() (and thus
160* the wakeup) are called asynchronously from an interrupt, rather than
161* from the scheduler. We can avoid the race by calling the wakeup
162* from the scheduler queue and that's our fix: Now, at the end of
163* write_bulk_callback() we queue up a wakeup call on the scheduler
164* task queue. We still also invoke the wakeup directly since that
165* squeezes a bit more performance out of the driver, and any lost
166* race conditions will get cleaned up at the next scheduler run.
167*
168* NOTE: The problem also goes away if you comment out
169* the two code lines in write_chan() where current->state
170* is set to TASK_RUNNING just before calling driver.write() and to
171* TASK_INTERRUPTIBLE immediately afterwards. This is why the
172* problem did not show up with the 2.2 kernels -- they do not
173* include that code.
174*
175* (5/16/2000) pberger and borchers
176* -- Added timeouts to sleeps, to defend against lost wake ups.
177* -- Handle transition to/from B0 baud rate in digi_set_termios.
178*
179* (5/13/2000) pberger and borchers
180* -- All commands now sent on out of band port, using
181* digi_write_oob_command.
182* -- Get modem control signals whenever they change, support TIOCMGET/
183* SET/BIS/BIC ioctls.
184* -- digi_set_termios now supports parity, word size, stop bits, and
185* receive enable.
186* -- Cleaned up open and close, use digi_set_termios and
187* digi_write_oob_command to set port parameters.
188* -- Added digi_startup_device to start read chains on all ports.
189* -- Write buffer is only used when count==1, to be sure put_char can
190* write a char (unless the buffer is full).
191*
192* (5/10/2000) pberger and borchers
193* -- Added MOD_INC_USE_COUNT/MOD_DEC_USE_COUNT calls on open/close.
194* -- Fixed problem where the first incoming character is lost on
195* port opens after the first close on that port. Now we keep
196* the read_urb chain open until shutdown.
197* -- Added more port conditioning calls in digi_open and digi_close.
198* -- Convert port->active to a use count so that we can deal with multiple
199* opens and closes properly.
200* -- Fixed some problems with the locking code.
201*
202* (5/3/2000) pberger and borchers
203* -- First alpha version of the driver--many known limitations and bugs.
204*
205*
206* Locking and SMP
207*
208* - Each port, including the out-of-band port, has a lock used to
209* serialize all access to the port's private structure.
210* - The port lock is also used to serialize all writes and access to
211* the port's URB.
212* - The port lock is also used for the port write_wait condition
213* variable. Holding the port lock will prevent a wake up on the
214* port's write_wait; this can be used with cond_wait_... to be sure
215* the wake up is not lost in a race when dropping the lock and
216* sleeping waiting for the wakeup.
217* - digi_write() does not sleep, since it is sometimes called on
218* interrupt time.
219* - digi_write_bulk_callback() and digi_read_bulk_callback() are
220* called directly from interrupts. Hence spin_lock_irqsave()
221* and spin_unlock_irqrestore() are used in the rest of the code
222* for any locks they acquire.
223* - digi_write_bulk_callback() gets the port lock before waking up
224* processes sleeping on the port write_wait. It also schedules
225* wake ups so they happen from the scheduler, because the tty
226* system can miss wake ups from interrupts.
227* - All sleeps use a timeout of DIGI_RETRY_TIMEOUT before looping to
228* recheck the condition they are sleeping on. This is defensive,
229* in case a wake up is lost.
230* - Following Documentation/DocBook/kernel-locking.tmpl no spin locks
231* are held when calling copy_to/from_user or printk.
232*/ 16*/
233 17
234#include <linux/kernel.h> 18#include <linux/kernel.h>