1 /************************************************************************
2 * Copyright 2003 Digi International (www.digi.com)
4 * Copyright (C) 2004 IBM Corporation. All rights reserved.
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2, or (at your option)
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY, EXPRESS OR IMPLIED; without even the
13 * implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
14 * PURPOSE. See the GNU General Public License for more details.
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 59 * Temple Place - Suite 330, Boston,
21 * Contact Information:
22 * Scott H Kilau <Scott_Kilau@digi.com>
23 * Ananda Venkatarman <mansarov@us.ibm.com>
25 * 01/19/06: changed jsm_input routine to use the dynamically allocated
26 * tty_buffer changes. Contributors: Scott Kilau and Ananda V.
27 ***********************************************************************/
28 #include <linux/tty.h>
29 #include <linux/tty_flip.h>
30 #include <linux/serial_reg.h>
31 #include <linux/delay.h> /* For udelay */
32 #include <linux/pci.h>
36 static void jsm_carrier(struct jsm_channel
*ch
);
38 static inline int jsm_get_mstat(struct jsm_channel
*ch
)
43 jsm_printk(IOCTL
, INFO
, &ch
->ch_bd
->pci_dev
, "start\n");
45 mstat
= (ch
->ch_mostat
| ch
->ch_mistat
);
49 if (mstat
& UART_MCR_DTR
)
51 if (mstat
& UART_MCR_RTS
)
53 if (mstat
& UART_MSR_CTS
)
55 if (mstat
& UART_MSR_DSR
)
57 if (mstat
& UART_MSR_RI
)
59 if (mstat
& UART_MSR_DCD
)
62 jsm_printk(IOCTL
, INFO
, &ch
->ch_bd
->pci_dev
, "finish\n");
66 static unsigned int jsm_tty_tx_empty(struct uart_port
*port
)
72 * Return modem signals to ld.
74 static unsigned int jsm_tty_get_mctrl(struct uart_port
*port
)
77 struct jsm_channel
*channel
= (struct jsm_channel
*)port
;
79 jsm_printk(IOCTL
, INFO
, &channel
->ch_bd
->pci_dev
, "start\n");
81 result
= jsm_get_mstat(channel
);
86 jsm_printk(IOCTL
, INFO
, &channel
->ch_bd
->pci_dev
, "finish\n");
92 * jsm_set_modem_info()
94 * Set modem signals, called by ld.
96 static void jsm_tty_set_mctrl(struct uart_port
*port
, unsigned int mctrl
)
98 struct jsm_channel
*channel
= (struct jsm_channel
*)port
;
100 jsm_printk(IOCTL
, INFO
, &channel
->ch_bd
->pci_dev
, "start\n");
102 if (mctrl
& TIOCM_RTS
)
103 channel
->ch_mostat
|= UART_MCR_RTS
;
105 channel
->ch_mostat
&= ~UART_MCR_RTS
;
107 if (mctrl
& TIOCM_DTR
)
108 channel
->ch_mostat
|= UART_MCR_DTR
;
110 channel
->ch_mostat
&= ~UART_MCR_DTR
;
112 channel
->ch_bd
->bd_ops
->assert_modem_signals(channel
);
114 jsm_printk(IOCTL
, INFO
, &channel
->ch_bd
->pci_dev
, "finish\n");
118 static void jsm_tty_start_tx(struct uart_port
*port
)
120 struct jsm_channel
*channel
= (struct jsm_channel
*)port
;
122 jsm_printk(IOCTL
, INFO
, &channel
->ch_bd
->pci_dev
, "start\n");
124 channel
->ch_flags
&= ~(CH_STOP
);
127 jsm_printk(IOCTL
, INFO
, &channel
->ch_bd
->pci_dev
, "finish\n");
130 static void jsm_tty_stop_tx(struct uart_port
*port
)
132 struct jsm_channel
*channel
= (struct jsm_channel
*)port
;
134 jsm_printk(IOCTL
, INFO
, &channel
->ch_bd
->pci_dev
, "start\n");
136 channel
->ch_flags
|= (CH_STOP
);
138 jsm_printk(IOCTL
, INFO
, &channel
->ch_bd
->pci_dev
, "finish\n");
141 static void jsm_tty_send_xchar(struct uart_port
*port
, char ch
)
143 unsigned long lock_flags
;
144 struct jsm_channel
*channel
= (struct jsm_channel
*)port
;
145 struct ktermios
*termios
;
147 spin_lock_irqsave(&port
->lock
, lock_flags
);
148 termios
= port
->info
->tty
->termios
;
149 if (ch
== termios
->c_cc
[VSTART
])
150 channel
->ch_bd
->bd_ops
->send_start_character(channel
);
152 if (ch
== termios
->c_cc
[VSTOP
])
153 channel
->ch_bd
->bd_ops
->send_stop_character(channel
);
154 spin_unlock_irqrestore(&port
->lock
, lock_flags
);
157 static void jsm_tty_stop_rx(struct uart_port
*port
)
159 struct jsm_channel
*channel
= (struct jsm_channel
*)port
;
161 channel
->ch_bd
->bd_ops
->disable_receiver(channel
);
164 static void jsm_tty_break(struct uart_port
*port
, int break_state
)
166 unsigned long lock_flags
;
167 struct jsm_channel
*channel
= (struct jsm_channel
*)port
;
169 spin_lock_irqsave(&port
->lock
, lock_flags
);
170 if (break_state
== -1)
171 channel
->ch_bd
->bd_ops
->send_break(channel
);
173 channel
->ch_bd
->bd_ops
->clear_break(channel
, 0);
175 spin_unlock_irqrestore(&port
->lock
, lock_flags
);
178 static int jsm_tty_open(struct uart_port
*port
)
180 struct jsm_board
*brd
;
182 struct jsm_channel
*channel
= (struct jsm_channel
*)port
;
183 struct ktermios
*termios
;
185 /* Get board pointer from our array of majors we have allocated */
186 brd
= channel
->ch_bd
;
189 * Allocate channel buffers for read/write/error.
190 * Set flag, so we don't get trounced on.
192 channel
->ch_flags
|= (CH_OPENING
);
194 /* Drop locks, as malloc with GFP_KERNEL can sleep */
196 if (!channel
->ch_rqueue
) {
197 channel
->ch_rqueue
= kzalloc(RQUEUESIZE
, GFP_KERNEL
);
198 if (!channel
->ch_rqueue
) {
199 jsm_printk(INIT
, ERR
, &channel
->ch_bd
->pci_dev
,
200 "unable to allocate read queue buf");
204 if (!channel
->ch_equeue
) {
205 channel
->ch_equeue
= kzalloc(EQUEUESIZE
, GFP_KERNEL
);
206 if (!channel
->ch_equeue
) {
207 jsm_printk(INIT
, ERR
, &channel
->ch_bd
->pci_dev
,
208 "unable to allocate error queue buf");
212 if (!channel
->ch_wqueue
) {
213 channel
->ch_wqueue
= kzalloc(WQUEUESIZE
, GFP_KERNEL
);
214 if (!channel
->ch_wqueue
) {
215 jsm_printk(INIT
, ERR
, &channel
->ch_bd
->pci_dev
,
216 "unable to allocate write queue buf");
221 channel
->ch_flags
&= ~(CH_OPENING
);
223 * Initialize if neither terminal is open.
225 jsm_printk(OPEN
, INFO
, &channel
->ch_bd
->pci_dev
,
226 "jsm_open: initializing channel in open...\n");
229 * Flush input queues.
231 channel
->ch_r_head
= channel
->ch_r_tail
= 0;
232 channel
->ch_e_head
= channel
->ch_e_tail
= 0;
233 channel
->ch_w_head
= channel
->ch_w_tail
= 0;
235 brd
->bd_ops
->flush_uart_write(channel
);
236 brd
->bd_ops
->flush_uart_read(channel
);
238 channel
->ch_flags
= 0;
239 channel
->ch_cached_lsr
= 0;
240 channel
->ch_stops_sent
= 0;
242 termios
= port
->info
->tty
->termios
;
243 channel
->ch_c_cflag
= termios
->c_cflag
;
244 channel
->ch_c_iflag
= termios
->c_iflag
;
245 channel
->ch_c_oflag
= termios
->c_oflag
;
246 channel
->ch_c_lflag
= termios
->c_lflag
;
247 channel
->ch_startc
= termios
->c_cc
[VSTART
];
248 channel
->ch_stopc
= termios
->c_cc
[VSTOP
];
250 /* Tell UART to init itself */
251 brd
->bd_ops
->uart_init(channel
);
254 * Run param in case we changed anything
256 brd
->bd_ops
->param(channel
);
258 jsm_carrier(channel
);
260 channel
->ch_open_count
++;
262 jsm_printk(OPEN
, INFO
, &channel
->ch_bd
->pci_dev
, "finish\n");
266 static void jsm_tty_close(struct uart_port
*port
)
268 struct jsm_board
*bd
;
270 struct jsm_channel
*channel
= (struct jsm_channel
*)port
;
272 jsm_printk(CLOSE
, INFO
, &channel
->ch_bd
->pci_dev
, "start\n");
275 ts
= channel
->uart_port
.info
->tty
->termios
;
277 channel
->ch_flags
&= ~(CH_STOPI
);
279 channel
->ch_open_count
--;
282 * If we have HUPCL set, lower DTR and RTS
284 if (channel
->ch_c_cflag
& HUPCL
) {
285 jsm_printk(CLOSE
, INFO
, &channel
->ch_bd
->pci_dev
,
286 "Close. HUPCL set, dropping DTR/RTS\n");
289 channel
->ch_mostat
&= ~(UART_MCR_DTR
| UART_MCR_RTS
);
290 bd
->bd_ops
->assert_modem_signals(channel
);
293 channel
->ch_old_baud
= 0;
295 /* Turn off UART interrupts for this port */
296 channel
->ch_bd
->bd_ops
->uart_off(channel
);
298 jsm_printk(CLOSE
, INFO
, &channel
->ch_bd
->pci_dev
, "finish\n");
301 static void jsm_tty_set_termios(struct uart_port
*port
,
302 struct ktermios
*termios
,
303 struct ktermios
*old_termios
)
305 unsigned long lock_flags
;
306 struct jsm_channel
*channel
= (struct jsm_channel
*)port
;
308 spin_lock_irqsave(&port
->lock
, lock_flags
);
309 channel
->ch_c_cflag
= termios
->c_cflag
;
310 channel
->ch_c_iflag
= termios
->c_iflag
;
311 channel
->ch_c_oflag
= termios
->c_oflag
;
312 channel
->ch_c_lflag
= termios
->c_lflag
;
313 channel
->ch_startc
= termios
->c_cc
[VSTART
];
314 channel
->ch_stopc
= termios
->c_cc
[VSTOP
];
316 channel
->ch_bd
->bd_ops
->param(channel
);
317 jsm_carrier(channel
);
318 spin_unlock_irqrestore(&port
->lock
, lock_flags
);
321 static const char *jsm_tty_type(struct uart_port
*port
)
326 static void jsm_tty_release_port(struct uart_port
*port
)
330 static int jsm_tty_request_port(struct uart_port
*port
)
335 static void jsm_config_port(struct uart_port
*port
, int flags
)
337 port
->type
= PORT_JSM
;
340 static struct uart_ops jsm_ops
= {
341 .tx_empty
= jsm_tty_tx_empty
,
342 .set_mctrl
= jsm_tty_set_mctrl
,
343 .get_mctrl
= jsm_tty_get_mctrl
,
344 .stop_tx
= jsm_tty_stop_tx
,
345 .start_tx
= jsm_tty_start_tx
,
346 .send_xchar
= jsm_tty_send_xchar
,
347 .stop_rx
= jsm_tty_stop_rx
,
348 .break_ctl
= jsm_tty_break
,
349 .startup
= jsm_tty_open
,
350 .shutdown
= jsm_tty_close
,
351 .set_termios
= jsm_tty_set_termios
,
352 .type
= jsm_tty_type
,
353 .release_port
= jsm_tty_release_port
,
354 .request_port
= jsm_tty_request_port
,
355 .config_port
= jsm_config_port
,
361 * Init the tty subsystem. Called once per board after board has been
362 * downloaded and init'ed.
364 int jsm_tty_init(struct jsm_board
*brd
)
368 struct jsm_channel
*ch
;
373 jsm_printk(INIT
, INFO
, &brd
->pci_dev
, "start\n");
376 * Initialize board structure elements.
379 brd
->nasync
= brd
->maxports
;
382 * Allocate channel memory that might not have been allocated
383 * when the driver was first loaded.
385 for (i
= 0; i
< brd
->nasync
; i
++) {
386 if (!brd
->channels
[i
]) {
389 * Okay to malloc with GFP_KERNEL, we are not at
390 * interrupt context, and there are no locks held.
392 brd
->channels
[i
] = kzalloc(sizeof(struct jsm_channel
), GFP_KERNEL
);
393 if (!brd
->channels
[i
]) {
394 jsm_printk(CORE
, ERR
, &brd
->pci_dev
,
395 "%s:%d Unable to allocate memory for channel struct\n",
401 ch
= brd
->channels
[0];
402 vaddr
= brd
->re_map_membase
;
404 /* Set up channel variables */
405 for (i
= 0; i
< brd
->nasync
; i
++, ch
= brd
->channels
[i
]) {
407 if (!brd
->channels
[i
])
410 spin_lock_init(&ch
->ch_lock
);
412 if (brd
->bd_uart_offset
== 0x200)
413 ch
->ch_neo_uart
= vaddr
+ (brd
->bd_uart_offset
* i
);
418 /* .25 second delay */
419 ch
->ch_close_delay
= 250;
421 init_waitqueue_head(&ch
->ch_flags_wait
);
424 jsm_printk(INIT
, INFO
, &brd
->pci_dev
, "finish\n");
428 int jsm_uart_port_init(struct jsm_board
*brd
)
431 struct jsm_channel
*ch
;
436 jsm_printk(INIT
, INFO
, &brd
->pci_dev
, "start\n");
439 * Initialize board structure elements.
442 brd
->nasync
= brd
->maxports
;
444 /* Set up channel variables */
445 for (i
= 0; i
< brd
->nasync
; i
++, ch
= brd
->channels
[i
]) {
447 if (!brd
->channels
[i
])
450 brd
->channels
[i
]->uart_port
.irq
= brd
->irq
;
451 brd
->channels
[i
]->uart_port
.uartclk
= 14745600;
452 brd
->channels
[i
]->uart_port
.type
= PORT_JSM
;
453 brd
->channels
[i
]->uart_port
.iotype
= UPIO_MEM
;
454 brd
->channels
[i
]->uart_port
.membase
= brd
->re_map_membase
;
455 brd
->channels
[i
]->uart_port
.fifosize
= 16;
456 brd
->channels
[i
]->uart_port
.ops
= &jsm_ops
;
457 brd
->channels
[i
]->uart_port
.line
= brd
->channels
[i
]->ch_portnum
+ brd
->boardnum
* 2;
458 if (uart_add_one_port (&jsm_uart_driver
, &brd
->channels
[i
]->uart_port
))
459 printk(KERN_INFO
"Added device failed\n");
461 printk(KERN_INFO
"Added device \n");
464 jsm_printk(INIT
, INFO
, &brd
->pci_dev
, "finish\n");
468 int jsm_remove_uart_port(struct jsm_board
*brd
)
471 struct jsm_channel
*ch
;
476 jsm_printk(INIT
, INFO
, &brd
->pci_dev
, "start\n");
479 * Initialize board structure elements.
482 brd
->nasync
= brd
->maxports
;
484 /* Set up channel variables */
485 for (i
= 0; i
< brd
->nasync
; i
++) {
487 if (!brd
->channels
[i
])
490 ch
= brd
->channels
[i
];
492 uart_remove_one_port(&jsm_uart_driver
, &brd
->channels
[i
]->uart_port
);
495 jsm_printk(INIT
, INFO
, &brd
->pci_dev
, "finish\n");
499 void jsm_input(struct jsm_channel
*ch
)
501 struct jsm_board
*bd
;
502 struct tty_struct
*tp
;
503 struct tty_ldisc
*ld
;
508 unsigned long lock_flags
;
515 jsm_printk(READ
, INFO
, &ch
->ch_bd
->pci_dev
, "start\n");
520 tp
= ch
->uart_port
.info
->tty
;
526 spin_lock_irqsave(&ch
->ch_lock
, lock_flags
);
529 *Figure the number of characters in the buffer.
530 *Exit immediately if none.
535 head
= ch
->ch_r_head
& rmask
;
536 tail
= ch
->ch_r_tail
& rmask
;
538 data_len
= (head
- tail
) & rmask
;
540 spin_unlock_irqrestore(&ch
->ch_lock
, lock_flags
);
544 jsm_printk(READ
, INFO
, &ch
->ch_bd
->pci_dev
, "start\n");
547 *If the device is not open, or CREAD is off, flush
548 *input data and return immediately.
551 !(tp
->termios
->c_cflag
& CREAD
) ) {
553 jsm_printk(READ
, INFO
, &ch
->ch_bd
->pci_dev
,
554 "input. dropping %d bytes on port %d...\n", data_len
, ch
->ch_portnum
);
555 ch
->ch_r_head
= tail
;
557 /* Force queue flow control to be released, if needed */
558 jsm_check_queue_flow_control(ch
);
560 spin_unlock_irqrestore(&ch
->ch_lock
, lock_flags
);
565 * If we are throttled, simply don't read any data.
567 if (ch
->ch_flags
& CH_STOPI
) {
568 spin_unlock_irqrestore(&ch
->ch_lock
, lock_flags
);
569 jsm_printk(READ
, INFO
, &ch
->ch_bd
->pci_dev
,
570 "Port %d throttled, not reading any data. head: %x tail: %x\n",
571 ch
->ch_portnum
, head
, tail
);
575 jsm_printk(READ
, INFO
, &ch
->ch_bd
->pci_dev
, "start 2\n");
578 * If the rxbuf is empty and we are not throttled, put as much
579 * as we can directly into the linux TTY buffer.
582 flip_len
= TTY_FLIPBUF_SIZE
;
584 len
= min(data_len
, flip_len
);
585 len
= min(len
, (N_TTY_BUF_SIZE
- 1) - tp
->read_cnt
);
586 ld
= tty_ldisc_ref(tp
);
589 * If we were unable to get a reference to the ld,
590 * don't flush our buffer, and act like the ld doesn't
591 * have any space to put the data right now.
597 * If ld doesn't have a pointer to a receive_buf function,
598 * flush the data, then act like the ld doesn't have any
599 * space to put the data right now.
601 if (!ld
->receive_buf
) {
602 ch
->ch_r_head
= ch
->ch_r_tail
;
608 spin_unlock_irqrestore(&ch
->ch_lock
, lock_flags
);
609 jsm_printk(READ
, INFO
, &ch
->ch_bd
->pci_dev
, "jsm_input 1\n");
615 len
= tty_buffer_request_room(tp
, len
);
619 * n now contains the most amount of data we can copy,
620 * bounded either by the flip buffer size or the amount
621 * of data the card actually has pending...
624 s
= ((head
>= tail
) ? head
: RQUEUESIZE
) - tail
;
631 * If conditions are such that ld needs to see all
632 * UART errors, we will have to walk each character
633 * and error byte and send them to the buffer one at
637 if (I_PARMRK(tp
) || I_BRKINT(tp
) || I_INPCK(tp
)) {
638 for (i
= 0; i
< s
; i
++) {
640 * Give the Linux ld the flags in the
643 if (*(ch
->ch_equeue
+tail
+i
) & UART_LSR_BI
)
644 tty_insert_flip_char(tp
, *(ch
->ch_rqueue
+tail
+i
), TTY_BREAK
);
645 else if (*(ch
->ch_equeue
+tail
+i
) & UART_LSR_PE
)
646 tty_insert_flip_char(tp
, *(ch
->ch_rqueue
+tail
+i
), TTY_PARITY
);
647 else if (*(ch
->ch_equeue
+tail
+i
) & UART_LSR_FE
)
648 tty_insert_flip_char(tp
, *(ch
->ch_rqueue
+tail
+i
), TTY_FRAME
);
650 tty_insert_flip_char(tp
, *(ch
->ch_rqueue
+tail
+i
), TTY_NORMAL
);
653 tty_insert_flip_string(tp
, ch
->ch_rqueue
+ tail
, s
) ;
657 /* Flip queue if needed */
661 ch
->ch_r_tail
= tail
& rmask
;
662 ch
->ch_e_tail
= tail
& rmask
;
663 jsm_check_queue_flow_control(ch
);
664 spin_unlock_irqrestore(&ch
->ch_lock
, lock_flags
);
666 /* Tell the tty layer its okay to "eat" the data now */
667 tty_flip_buffer_push(tp
);
672 jsm_printk(IOCTL
, INFO
, &ch
->ch_bd
->pci_dev
, "finish\n");
675 static void jsm_carrier(struct jsm_channel
*ch
)
677 struct jsm_board
*bd
;
679 int virt_carrier
= 0;
680 int phys_carrier
= 0;
682 jsm_printk(CARR
, INFO
, &ch
->ch_bd
->pci_dev
, "start\n");
691 if (ch
->ch_mistat
& UART_MSR_DCD
) {
692 jsm_printk(CARR
, INFO
, &ch
->ch_bd
->pci_dev
,
693 "mistat: %x D_CD: %x\n", ch
->ch_mistat
, ch
->ch_mistat
& UART_MSR_DCD
);
697 if (ch
->ch_c_cflag
& CLOCAL
)
700 jsm_printk(CARR
, INFO
, &ch
->ch_bd
->pci_dev
,
701 "DCD: physical: %d virt: %d\n", phys_carrier
, virt_carrier
);
704 * Test for a VIRTUAL carrier transition to HIGH.
706 if (((ch
->ch_flags
& CH_FCAR
) == 0) && (virt_carrier
== 1)) {
709 * When carrier rises, wake any threads waiting
710 * for carrier in the open routine.
713 jsm_printk(CARR
, INFO
, &ch
->ch_bd
->pci_dev
,
714 "carrier: virt DCD rose\n");
716 if (waitqueue_active(&(ch
->ch_flags_wait
)))
717 wake_up_interruptible(&ch
->ch_flags_wait
);
721 * Test for a PHYSICAL carrier transition to HIGH.
723 if (((ch
->ch_flags
& CH_CD
) == 0) && (phys_carrier
== 1)) {
726 * When carrier rises, wake any threads waiting
727 * for carrier in the open routine.
730 jsm_printk(CARR
, INFO
, &ch
->ch_bd
->pci_dev
,
731 "carrier: physical DCD rose\n");
733 if (waitqueue_active(&(ch
->ch_flags_wait
)))
734 wake_up_interruptible(&ch
->ch_flags_wait
);
738 * Test for a PHYSICAL transition to low, so long as we aren't
739 * currently ignoring physical transitions (which is what "virtual
740 * carrier" indicates).
742 * The transition of the virtual carrier to low really doesn't
743 * matter... it really only means "ignore carrier state", not
744 * "make pretend that carrier is there".
746 if ((virt_carrier
== 0) && ((ch
->ch_flags
& CH_CD
) != 0)
747 && (phys_carrier
== 0)) {
749 * When carrier drops:
751 * Drop carrier on all open units.
753 * Flush queues, waking up any task waiting in the
756 * Send a hangup to the control terminal.
758 * Enable all select calls.
760 if (waitqueue_active(&(ch
->ch_flags_wait
)))
761 wake_up_interruptible(&ch
->ch_flags_wait
);
765 * Make sure that our cached values reflect the current reality.
767 if (virt_carrier
== 1)
768 ch
->ch_flags
|= CH_FCAR
;
770 ch
->ch_flags
&= ~CH_FCAR
;
772 if (phys_carrier
== 1)
773 ch
->ch_flags
|= CH_CD
;
775 ch
->ch_flags
&= ~CH_CD
;
779 void jsm_check_queue_flow_control(struct jsm_channel
*ch
)
781 struct board_ops
*bd_ops
= ch
->ch_bd
->bd_ops
;
784 /* Store how much space we have left in the queue */
785 if ((qleft
= ch
->ch_r_tail
- ch
->ch_r_head
- 1) < 0)
786 qleft
+= RQUEUEMASK
+ 1;
789 * Check to see if we should enforce flow control on our queue because
790 * the ld (or user) isn't reading data out of our queue fast enuf.
792 * NOTE: This is done based on what the current flow control of the
795 * 1) HWFLOW (RTS) - Turn off the UART's Receive interrupt.
796 * This will cause the UART's FIFO to back up, and force
797 * the RTS signal to be dropped.
798 * 2) SWFLOW (IXOFF) - Keep trying to send a stop character to
799 * the other side, in hopes it will stop sending data to us.
800 * 3) NONE - Nothing we can do. We will simply drop any extra data
801 * that gets sent into us when the queue fills up.
805 if (ch
->ch_c_cflag
& CRTSCTS
) {
806 if(!(ch
->ch_flags
& CH_RECEIVER_OFF
)) {
807 bd_ops
->disable_receiver(ch
);
808 ch
->ch_flags
|= (CH_RECEIVER_OFF
);
809 jsm_printk(READ
, INFO
, &ch
->ch_bd
->pci_dev
,
810 "Internal queue hit hilevel mark (%d)! Turning off interrupts.\n",
815 else if (ch
->ch_c_iflag
& IXOFF
) {
816 if (ch
->ch_stops_sent
<= MAX_STOPS_SENT
) {
817 bd_ops
->send_stop_character(ch
);
819 jsm_printk(READ
, INFO
, &ch
->ch_bd
->pci_dev
,
820 "Sending stop char! Times sent: %x\n", ch
->ch_stops_sent
);
826 * Check to see if we should unenforce flow control because
827 * ld (or user) finally read enuf data out of our queue.
829 * NOTE: This is done based on what the current flow control of the
832 * 1) HWFLOW (RTS) - Turn back on the UART's Receive interrupt.
833 * This will cause the UART's FIFO to raise RTS back up,
834 * which will allow the other side to start sending data again.
835 * 2) SWFLOW (IXOFF) - Send a start character to
836 * the other side, so it will start sending data to us again.
837 * 3) NONE - Do nothing. Since we didn't do anything to turn off the
838 * other side, we don't need to do anything now.
840 if (qleft
> (RQUEUESIZE
/ 2)) {
842 if (ch
->ch_c_cflag
& CRTSCTS
) {
843 if (ch
->ch_flags
& CH_RECEIVER_OFF
) {
844 bd_ops
->enable_receiver(ch
);
845 ch
->ch_flags
&= ~(CH_RECEIVER_OFF
);
846 jsm_printk(READ
, INFO
, &ch
->ch_bd
->pci_dev
,
847 "Internal queue hit lowlevel mark (%d)! Turning on interrupts.\n",
852 else if (ch
->ch_c_iflag
& IXOFF
&& ch
->ch_stops_sent
) {
853 ch
->ch_stops_sent
= 0;
854 bd_ops
->send_start_character(ch
);
855 jsm_printk(READ
, INFO
, &ch
->ch_bd
->pci_dev
, "Sending start char!\n");
863 * Take data from the user or kernel and send it out to the FEP.
864 * In here exists all the Transparent Print magic as well.
866 int jsm_tty_write(struct uart_port
*port
)
868 int bufcount
= 0, n
= 0;
869 int data_count
= 0,data_count1
=0;
874 int temp_tail
= port
->info
->xmit
.tail
;
875 struct jsm_channel
*channel
= (struct jsm_channel
*)port
;
878 head
= (channel
->ch_w_head
) & tmask
;
879 tail
= (channel
->ch_w_tail
) & tmask
;
881 if ((bufcount
= tail
- head
- 1) < 0)
882 bufcount
+= WQUEUESIZE
;
887 remain
= WQUEUESIZE
- head
;
892 while ((port
->info
->xmit
.head
!= temp_tail
) &&
893 (data_count
< remain
)) {
894 channel
->ch_wqueue
[head
++] =
895 port
->info
->xmit
.buf
[temp_tail
];
898 temp_tail
&= (UART_XMIT_SIZE
- 1);
901 if (data_count
== remain
) head
= 0;
907 while ((port
->info
->xmit
.head
!= temp_tail
) &&
908 (data_count1
< remain
)) {
909 channel
->ch_wqueue
[head
++] =
910 port
->info
->xmit
.buf
[temp_tail
];
913 temp_tail
&= (UART_XMIT_SIZE
- 1);
919 port
->info
->xmit
.tail
= temp_tail
;
921 data_count
+= data_count1
;
924 channel
->ch_w_head
= head
;
928 channel
->ch_bd
->bd_ops
->copy_data_from_queue_to_uart(channel
);