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v3.5.6
 
  1/************************************************************************
  2 * Copyright 2003 Digi International (www.digi.com)
  3 *
  4 * Copyright (C) 2004 IBM Corporation. All rights reserved.
  5 *
  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)
  9 * any later version.
 10 *
 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.
 15 *
 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,
 19 * MA  02111-1307, USA.
 20 *
 21 * Contact Information:
 22 * Scott H Kilau <Scott_Kilau@digi.com>
 23 * Ananda Venkatarman <mansarov@us.ibm.com>
 24 * Modifications:
 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>
 33#include <linux/slab.h>
 34
 35#include "jsm.h"
 36
 37static DECLARE_BITMAP(linemap, MAXLINES);
 38
 39static void jsm_carrier(struct jsm_channel *ch);
 40
 41static inline int jsm_get_mstat(struct jsm_channel *ch)
 42{
 43	unsigned char mstat;
 44	unsigned result;
 45
 46	jsm_printk(IOCTL, INFO, &ch->ch_bd->pci_dev, "start\n");
 47
 48	mstat = (ch->ch_mostat | ch->ch_mistat);
 49
 50	result = 0;
 51
 52	if (mstat & UART_MCR_DTR)
 53		result |= TIOCM_DTR;
 54	if (mstat & UART_MCR_RTS)
 55		result |= TIOCM_RTS;
 56	if (mstat & UART_MSR_CTS)
 57		result |= TIOCM_CTS;
 58	if (mstat & UART_MSR_DSR)
 59		result |= TIOCM_DSR;
 60	if (mstat & UART_MSR_RI)
 61		result |= TIOCM_RI;
 62	if (mstat & UART_MSR_DCD)
 63		result |= TIOCM_CD;
 64
 65	jsm_printk(IOCTL, INFO, &ch->ch_bd->pci_dev, "finish\n");
 66	return result;
 67}
 68
 69static unsigned int jsm_tty_tx_empty(struct uart_port *port)
 70{
 71	return TIOCSER_TEMT;
 72}
 73
 74/*
 75 * Return modem signals to ld.
 76 */
 77static unsigned int jsm_tty_get_mctrl(struct uart_port *port)
 78{
 79	int result;
 80	struct jsm_channel *channel = (struct jsm_channel *)port;
 
 81
 82	jsm_printk(IOCTL, INFO, &channel->ch_bd->pci_dev, "start\n");
 83
 84	result = jsm_get_mstat(channel);
 85
 86	if (result < 0)
 87		return -ENXIO;
 88
 89	jsm_printk(IOCTL, INFO, &channel->ch_bd->pci_dev, "finish\n");
 90
 91	return result;
 92}
 93
 94/*
 95 * jsm_set_modem_info()
 96 *
 97 * Set modem signals, called by ld.
 98 */
 99static void jsm_tty_set_mctrl(struct uart_port *port, unsigned int mctrl)
100{
101	struct jsm_channel *channel = (struct jsm_channel *)port;
 
102
103	jsm_printk(IOCTL, INFO, &channel->ch_bd->pci_dev, "start\n");
104
105	if (mctrl & TIOCM_RTS)
106		channel->ch_mostat |= UART_MCR_RTS;
107	else
108		channel->ch_mostat &= ~UART_MCR_RTS;
109
110	if (mctrl & TIOCM_DTR)
111		channel->ch_mostat |= UART_MCR_DTR;
112	else
113		channel->ch_mostat &= ~UART_MCR_DTR;
114
115	channel->ch_bd->bd_ops->assert_modem_signals(channel);
116
117	jsm_printk(IOCTL, INFO, &channel->ch_bd->pci_dev, "finish\n");
118	udelay(10);
119}
120
121/*
122 * jsm_tty_write()
123 *
124 * Take data from the user or kernel and send it out to the FEP.
125 * In here exists all the Transparent Print magic as well.
126 */
127static void jsm_tty_write(struct uart_port *port)
128{
129	struct jsm_channel *channel;
 
130	channel = container_of(port, struct jsm_channel, uart_port);
131	channel->ch_bd->bd_ops->copy_data_from_queue_to_uart(channel);
132}
133
134static void jsm_tty_start_tx(struct uart_port *port)
135{
136	struct jsm_channel *channel = (struct jsm_channel *)port;
 
137
138	jsm_printk(IOCTL, INFO, &channel->ch_bd->pci_dev, "start\n");
139
140	channel->ch_flags &= ~(CH_STOP);
141	jsm_tty_write(port);
142
143	jsm_printk(IOCTL, INFO, &channel->ch_bd->pci_dev, "finish\n");
144}
145
146static void jsm_tty_stop_tx(struct uart_port *port)
147{
148	struct jsm_channel *channel = (struct jsm_channel *)port;
 
149
150	jsm_printk(IOCTL, INFO, &channel->ch_bd->pci_dev, "start\n");
151
152	channel->ch_flags |= (CH_STOP);
153
154	jsm_printk(IOCTL, INFO, &channel->ch_bd->pci_dev, "finish\n");
155}
156
157static void jsm_tty_send_xchar(struct uart_port *port, char ch)
158{
159	unsigned long lock_flags;
160	struct jsm_channel *channel = (struct jsm_channel *)port;
 
161	struct ktermios *termios;
162
163	spin_lock_irqsave(&port->lock, lock_flags);
164	termios = port->state->port.tty->termios;
165	if (ch == termios->c_cc[VSTART])
166		channel->ch_bd->bd_ops->send_start_character(channel);
167
168	if (ch == termios->c_cc[VSTOP])
169		channel->ch_bd->bd_ops->send_stop_character(channel);
170	spin_unlock_irqrestore(&port->lock, lock_flags);
171}
172
173static void jsm_tty_stop_rx(struct uart_port *port)
174{
175	struct jsm_channel *channel = (struct jsm_channel *)port;
 
176
177	channel->ch_bd->bd_ops->disable_receiver(channel);
178}
179
180static void jsm_tty_enable_ms(struct uart_port *port)
181{
182	/* Nothing needed */
183}
184
185static void jsm_tty_break(struct uart_port *port, int break_state)
186{
187	unsigned long lock_flags;
188	struct jsm_channel *channel = (struct jsm_channel *)port;
 
189
190	spin_lock_irqsave(&port->lock, lock_flags);
191	if (break_state == -1)
192		channel->ch_bd->bd_ops->send_break(channel);
193	else
194		channel->ch_bd->bd_ops->clear_break(channel, 0);
195
196	spin_unlock_irqrestore(&port->lock, lock_flags);
197}
198
199static int jsm_tty_open(struct uart_port *port)
200{
201	struct jsm_board *brd;
202	struct jsm_channel *channel = (struct jsm_channel *)port;
 
203	struct ktermios *termios;
204
205	/* Get board pointer from our array of majors we have allocated */
206	brd = channel->ch_bd;
207
208	/*
209	 * Allocate channel buffers for read/write/error.
210	 * Set flag, so we don't get trounced on.
211	 */
212	channel->ch_flags |= (CH_OPENING);
213
214	/* Drop locks, as malloc with GFP_KERNEL can sleep */
215
216	if (!channel->ch_rqueue) {
217		channel->ch_rqueue = kzalloc(RQUEUESIZE, GFP_KERNEL);
218		if (!channel->ch_rqueue) {
219			jsm_printk(INIT, ERR, &channel->ch_bd->pci_dev,
220				"unable to allocate read queue buf");
221			return -ENOMEM;
222		}
223	}
224	if (!channel->ch_equeue) {
225		channel->ch_equeue = kzalloc(EQUEUESIZE, GFP_KERNEL);
226		if (!channel->ch_equeue) {
227			jsm_printk(INIT, ERR, &channel->ch_bd->pci_dev,
228				"unable to allocate error queue buf");
229			return -ENOMEM;
230		}
231	}
232
233	channel->ch_flags &= ~(CH_OPENING);
234	/*
235	 * Initialize if neither terminal is open.
236	 */
237	jsm_printk(OPEN, INFO, &channel->ch_bd->pci_dev,
238		"jsm_open: initializing channel in open...\n");
239
240	/*
241	 * Flush input queues.
242	 */
243	channel->ch_r_head = channel->ch_r_tail = 0;
244	channel->ch_e_head = channel->ch_e_tail = 0;
245
246	brd->bd_ops->flush_uart_write(channel);
247	brd->bd_ops->flush_uart_read(channel);
248
249	channel->ch_flags = 0;
250	channel->ch_cached_lsr = 0;
251	channel->ch_stops_sent = 0;
252
253	termios = port->state->port.tty->termios;
254	channel->ch_c_cflag	= termios->c_cflag;
255	channel->ch_c_iflag	= termios->c_iflag;
256	channel->ch_c_oflag	= termios->c_oflag;
257	channel->ch_c_lflag	= termios->c_lflag;
258	channel->ch_startc	= termios->c_cc[VSTART];
259	channel->ch_stopc	= termios->c_cc[VSTOP];
260
261	/* Tell UART to init itself */
262	brd->bd_ops->uart_init(channel);
263
264	/*
265	 * Run param in case we changed anything
266	 */
267	brd->bd_ops->param(channel);
268
269	jsm_carrier(channel);
270
271	channel->ch_open_count++;
272
273	jsm_printk(OPEN, INFO, &channel->ch_bd->pci_dev, "finish\n");
274	return 0;
275}
276
277static void jsm_tty_close(struct uart_port *port)
278{
279	struct jsm_board *bd;
280	struct ktermios *ts;
281	struct jsm_channel *channel = (struct jsm_channel *)port;
282
283	jsm_printk(CLOSE, INFO, &channel->ch_bd->pci_dev, "start\n");
284
285	bd = channel->ch_bd;
286	ts = port->state->port.tty->termios;
287
288	channel->ch_flags &= ~(CH_STOPI);
289
290	channel->ch_open_count--;
291
292	/*
293	 * If we have HUPCL set, lower DTR and RTS
294	 */
295	if (channel->ch_c_cflag & HUPCL) {
296		jsm_printk(CLOSE, INFO, &channel->ch_bd->pci_dev,
297			"Close. HUPCL set, dropping DTR/RTS\n");
298
299		/* Drop RTS/DTR */
300		channel->ch_mostat &= ~(UART_MCR_DTR | UART_MCR_RTS);
301		bd->bd_ops->assert_modem_signals(channel);
302	}
303
304	/* Turn off UART interrupts for this port */
305	channel->ch_bd->bd_ops->uart_off(channel);
306
307	jsm_printk(CLOSE, INFO, &channel->ch_bd->pci_dev, "finish\n");
308}
309
310static void jsm_tty_set_termios(struct uart_port *port,
311				 struct ktermios *termios,
312				 struct ktermios *old_termios)
313{
314	unsigned long lock_flags;
315	struct jsm_channel *channel = (struct jsm_channel *)port;
 
316
317	spin_lock_irqsave(&port->lock, lock_flags);
318	channel->ch_c_cflag	= termios->c_cflag;
319	channel->ch_c_iflag	= termios->c_iflag;
320	channel->ch_c_oflag	= termios->c_oflag;
321	channel->ch_c_lflag	= termios->c_lflag;
322	channel->ch_startc	= termios->c_cc[VSTART];
323	channel->ch_stopc	= termios->c_cc[VSTOP];
324
325	channel->ch_bd->bd_ops->param(channel);
326	jsm_carrier(channel);
327	spin_unlock_irqrestore(&port->lock, lock_flags);
328}
329
330static const char *jsm_tty_type(struct uart_port *port)
331{
332	return "jsm";
333}
334
335static void jsm_tty_release_port(struct uart_port *port)
336{
337}
338
339static int jsm_tty_request_port(struct uart_port *port)
340{
341	return 0;
342}
343
344static void jsm_config_port(struct uart_port *port, int flags)
345{
346	port->type = PORT_JSM;
347}
348
349static struct uart_ops jsm_ops = {
350	.tx_empty	= jsm_tty_tx_empty,
351	.set_mctrl	= jsm_tty_set_mctrl,
352	.get_mctrl	= jsm_tty_get_mctrl,
353	.stop_tx	= jsm_tty_stop_tx,
354	.start_tx	= jsm_tty_start_tx,
355	.send_xchar	= jsm_tty_send_xchar,
356	.stop_rx	= jsm_tty_stop_rx,
357	.enable_ms	= jsm_tty_enable_ms,
358	.break_ctl	= jsm_tty_break,
359	.startup	= jsm_tty_open,
360	.shutdown	= jsm_tty_close,
361	.set_termios	= jsm_tty_set_termios,
362	.type		= jsm_tty_type,
363	.release_port	= jsm_tty_release_port,
364	.request_port	= jsm_tty_request_port,
365	.config_port	= jsm_config_port,
366};
367
368/*
369 * jsm_tty_init()
370 *
371 * Init the tty subsystem.  Called once per board after board has been
372 * downloaded and init'ed.
373 */
374int __devinit jsm_tty_init(struct jsm_board *brd)
375{
376	int i;
377	void __iomem *vaddr;
378	struct jsm_channel *ch;
379
380	if (!brd)
381		return -ENXIO;
382
383	jsm_printk(INIT, INFO, &brd->pci_dev, "start\n");
384
385	/*
386	 * Initialize board structure elements.
387	 */
388
389	brd->nasync = brd->maxports;
390
391	/*
392	 * Allocate channel memory that might not have been allocated
393	 * when the driver was first loaded.
394	 */
395	for (i = 0; i < brd->nasync; i++) {
396		if (!brd->channels[i]) {
397
398			/*
399			 * Okay to malloc with GFP_KERNEL, we are not at
400			 * interrupt context, and there are no locks held.
401			 */
402			brd->channels[i] = kzalloc(sizeof(struct jsm_channel), GFP_KERNEL);
403			if (!brd->channels[i]) {
404				jsm_printk(CORE, ERR, &brd->pci_dev,
405					"%s:%d Unable to allocate memory for channel struct\n",
406							 __FILE__, __LINE__);
407			}
408		}
409	}
410
411	ch = brd->channels[0];
412	vaddr = brd->re_map_membase;
413
414	/* Set up channel variables */
415	for (i = 0; i < brd->nasync; i++, ch = brd->channels[i]) {
416
417		if (!brd->channels[i])
418			continue;
419
420		spin_lock_init(&ch->ch_lock);
421
422		if (brd->bd_uart_offset == 0x200)
423			ch->ch_neo_uart =  vaddr + (brd->bd_uart_offset * i);
 
 
424
425		ch->ch_bd = brd;
426		ch->ch_portnum = i;
427
428		/* .25 second delay */
429		ch->ch_close_delay = 250;
430
431		init_waitqueue_head(&ch->ch_flags_wait);
432	}
433
434	jsm_printk(INIT, INFO, &brd->pci_dev, "finish\n");
435	return 0;
436}
437
438int jsm_uart_port_init(struct jsm_board *brd)
439{
440	int i, rc;
441	unsigned int line;
442	struct jsm_channel *ch;
443
444	if (!brd)
445		return -ENXIO;
446
447	jsm_printk(INIT, INFO, &brd->pci_dev, "start\n");
448
449	/*
450	 * Initialize board structure elements.
451	 */
452
453	brd->nasync = brd->maxports;
454
455	/* Set up channel variables */
456	for (i = 0; i < brd->nasync; i++, ch = brd->channels[i]) {
457
458		if (!brd->channels[i])
459			continue;
460
461		brd->channels[i]->uart_port.irq = brd->irq;
462		brd->channels[i]->uart_port.uartclk = 14745600;
463		brd->channels[i]->uart_port.type = PORT_JSM;
464		brd->channels[i]->uart_port.iotype = UPIO_MEM;
465		brd->channels[i]->uart_port.membase = brd->re_map_membase;
466		brd->channels[i]->uart_port.fifosize = 16;
467		brd->channels[i]->uart_port.ops = &jsm_ops;
468		line = find_first_zero_bit(linemap, MAXLINES);
469		if (line >= MAXLINES) {
470			printk(KERN_INFO "jsm: linemap is full, added device failed\n");
471			continue;
472		} else
473			set_bit(line, linemap);
474		brd->channels[i]->uart_port.line = line;
475		rc = uart_add_one_port (&jsm_uart_driver, &brd->channels[i]->uart_port);
476		if (rc){
477			printk(KERN_INFO "jsm: Port %d failed. Aborting...\n", i);
478			return rc;
479		}
480		else
481			printk(KERN_INFO "jsm: Port %d added\n", i);
482	}
483
484	jsm_printk(INIT, INFO, &brd->pci_dev, "finish\n");
485	return 0;
486}
487
488int jsm_remove_uart_port(struct jsm_board *brd)
489{
490	int i;
491	struct jsm_channel *ch;
492
493	if (!brd)
494		return -ENXIO;
495
496	jsm_printk(INIT, INFO, &brd->pci_dev, "start\n");
497
498	/*
499	 * Initialize board structure elements.
500	 */
501
502	brd->nasync = brd->maxports;
503
504	/* Set up channel variables */
505	for (i = 0; i < brd->nasync; i++) {
506
507		if (!brd->channels[i])
508			continue;
509
510		ch = brd->channels[i];
511
512		clear_bit(ch->uart_port.line, linemap);
513		uart_remove_one_port(&jsm_uart_driver, &brd->channels[i]->uart_port);
514	}
515
516	jsm_printk(INIT, INFO, &brd->pci_dev, "finish\n");
517	return 0;
518}
519
520void jsm_input(struct jsm_channel *ch)
521{
522	struct jsm_board *bd;
523	struct tty_struct *tp;
 
524	u32 rmask;
525	u16 head;
526	u16 tail;
527	int data_len;
528	unsigned long lock_flags;
529	int len = 0;
530	int n = 0;
531	int s = 0;
532	int i = 0;
533
534	jsm_printk(READ, INFO, &ch->ch_bd->pci_dev, "start\n");
535
536	if (!ch)
537		return;
538
539	tp = ch->uart_port.state->port.tty;
 
540
541	bd = ch->ch_bd;
542	if(!bd)
543		return;
544
545	spin_lock_irqsave(&ch->ch_lock, lock_flags);
546
547	/*
548	 *Figure the number of characters in the buffer.
549	 *Exit immediately if none.
550	 */
551
552	rmask = RQUEUEMASK;
553
554	head = ch->ch_r_head & rmask;
555	tail = ch->ch_r_tail & rmask;
556
557	data_len = (head - tail) & rmask;
558	if (data_len == 0) {
559		spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
560		return;
561	}
562
563	jsm_printk(READ, INFO, &ch->ch_bd->pci_dev, "start\n");
564
565	/*
566	 *If the device is not open, or CREAD is off, flush
567	 *input data and return immediately.
568	 */
569	if (!tp ||
570		!(tp->termios->c_cflag & CREAD) ) {
571
572		jsm_printk(READ, INFO, &ch->ch_bd->pci_dev,
573			"input. dropping %d bytes on port %d...\n", data_len, ch->ch_portnum);
 
574		ch->ch_r_head = tail;
575
576		/* Force queue flow control to be released, if needed */
577		jsm_check_queue_flow_control(ch);
578
579		spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
580		return;
581	}
582
583	/*
584	 * If we are throttled, simply don't read any data.
585	 */
586	if (ch->ch_flags & CH_STOPI) {
587		spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
588		jsm_printk(READ, INFO, &ch->ch_bd->pci_dev,
589			"Port %d throttled, not reading any data. head: %x tail: %x\n",
590			ch->ch_portnum, head, tail);
591		return;
592	}
593
594	jsm_printk(READ, INFO, &ch->ch_bd->pci_dev, "start 2\n");
595
596	if (data_len <= 0) {
597		spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
598		jsm_printk(READ, INFO, &ch->ch_bd->pci_dev, "jsm_input 1\n");
599		return;
600	}
601
602	len = tty_buffer_request_room(tp, data_len);
603	n = len;
604
605	/*
606	 * n now contains the most amount of data we can copy,
607	 * bounded either by the flip buffer size or the amount
608	 * of data the card actually has pending...
609	 */
610	while (n) {
611		s = ((head >= tail) ? head : RQUEUESIZE) - tail;
612		s = min(s, n);
613
614		if (s <= 0)
615			break;
616
617			/*
618			 * If conditions are such that ld needs to see all
619			 * UART errors, we will have to walk each character
620			 * and error byte and send them to the buffer one at
621			 * a time.
622			 */
623
624		if (I_PARMRK(tp) || I_BRKINT(tp) || I_INPCK(tp)) {
625			for (i = 0; i < s; i++) {
626				/*
627				 * Give the Linux ld the flags in the
628				 * format it likes.
629				 */
630				if (*(ch->ch_equeue +tail +i) & UART_LSR_BI)
631					tty_insert_flip_char(tp, *(ch->ch_rqueue +tail +i),  TTY_BREAK);
632				else if (*(ch->ch_equeue +tail +i) & UART_LSR_PE)
633					tty_insert_flip_char(tp, *(ch->ch_rqueue +tail +i), TTY_PARITY);
634				else if (*(ch->ch_equeue +tail +i) & UART_LSR_FE)
635					tty_insert_flip_char(tp, *(ch->ch_rqueue +tail +i), TTY_FRAME);
636				else
637					tty_insert_flip_char(tp, *(ch->ch_rqueue +tail +i), TTY_NORMAL);
638			}
639		} else {
640			tty_insert_flip_string(tp, ch->ch_rqueue + tail, s) ;
641		}
642		tail += s;
643		n -= s;
644		/* Flip queue if needed */
645		tail &= rmask;
646	}
647
648	ch->ch_r_tail = tail & rmask;
649	ch->ch_e_tail = tail & rmask;
650	jsm_check_queue_flow_control(ch);
651	spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
652
653	/* Tell the tty layer its okay to "eat" the data now */
654	tty_flip_buffer_push(tp);
655
656	jsm_printk(IOCTL, INFO, &ch->ch_bd->pci_dev, "finish\n");
657}
658
659static void jsm_carrier(struct jsm_channel *ch)
660{
661	struct jsm_board *bd;
662
663	int virt_carrier = 0;
664	int phys_carrier = 0;
665
666	jsm_printk(CARR, INFO, &ch->ch_bd->pci_dev, "start\n");
667	if (!ch)
668		return;
669
670	bd = ch->ch_bd;
671
672	if (!bd)
673		return;
674
675	if (ch->ch_mistat & UART_MSR_DCD) {
676		jsm_printk(CARR, INFO, &ch->ch_bd->pci_dev,
677			"mistat: %x D_CD: %x\n", ch->ch_mistat, ch->ch_mistat & UART_MSR_DCD);
678		phys_carrier = 1;
679	}
680
681	if (ch->ch_c_cflag & CLOCAL)
682		virt_carrier = 1;
683
684	jsm_printk(CARR, INFO, &ch->ch_bd->pci_dev,
685		"DCD: physical: %d virt: %d\n", phys_carrier, virt_carrier);
686
687	/*
688	 * Test for a VIRTUAL carrier transition to HIGH.
689	 */
690	if (((ch->ch_flags & CH_FCAR) == 0) && (virt_carrier == 1)) {
691
692		/*
693		 * When carrier rises, wake any threads waiting
694		 * for carrier in the open routine.
695		 */
696
697		jsm_printk(CARR, INFO, &ch->ch_bd->pci_dev,
698			"carrier: virt DCD rose\n");
699
700		if (waitqueue_active(&(ch->ch_flags_wait)))
701			wake_up_interruptible(&ch->ch_flags_wait);
702	}
703
704	/*
705	 * Test for a PHYSICAL carrier transition to HIGH.
706	 */
707	if (((ch->ch_flags & CH_CD) == 0) && (phys_carrier == 1)) {
708
709		/*
710		 * When carrier rises, wake any threads waiting
711		 * for carrier in the open routine.
712		 */
713
714		jsm_printk(CARR, INFO, &ch->ch_bd->pci_dev,
715			"carrier: physical DCD rose\n");
716
717		if (waitqueue_active(&(ch->ch_flags_wait)))
718			wake_up_interruptible(&ch->ch_flags_wait);
719	}
720
721	/*
722	 *  Test for a PHYSICAL transition to low, so long as we aren't
723	 *  currently ignoring physical transitions (which is what "virtual
724	 *  carrier" indicates).
725	 *
726	 *  The transition of the virtual carrier to low really doesn't
727	 *  matter... it really only means "ignore carrier state", not
728	 *  "make pretend that carrier is there".
729	 */
730	if ((virt_carrier == 0) && ((ch->ch_flags & CH_CD) != 0)
731			&& (phys_carrier == 0)) {
732		/*
733		 *	When carrier drops:
734		 *
735		 *	Drop carrier on all open units.
736		 *
737		 *	Flush queues, waking up any task waiting in the
738		 *	line discipline.
739		 *
740		 *	Send a hangup to the control terminal.
741		 *
742		 *	Enable all select calls.
743		 */
744		if (waitqueue_active(&(ch->ch_flags_wait)))
745			wake_up_interruptible(&ch->ch_flags_wait);
746	}
747
748	/*
749	 *  Make sure that our cached values reflect the current reality.
750	 */
751	if (virt_carrier == 1)
752		ch->ch_flags |= CH_FCAR;
753	else
754		ch->ch_flags &= ~CH_FCAR;
755
756	if (phys_carrier == 1)
757		ch->ch_flags |= CH_CD;
758	else
759		ch->ch_flags &= ~CH_CD;
760}
761
762
763void jsm_check_queue_flow_control(struct jsm_channel *ch)
764{
765	struct board_ops *bd_ops = ch->ch_bd->bd_ops;
766	int qleft;
767
768	/* Store how much space we have left in the queue */
769	if ((qleft = ch->ch_r_tail - ch->ch_r_head - 1) < 0)
770		qleft += RQUEUEMASK + 1;
771
772	/*
773	 * Check to see if we should enforce flow control on our queue because
774	 * the ld (or user) isn't reading data out of our queue fast enuf.
775	 *
776	 * NOTE: This is done based on what the current flow control of the
777	 * port is set for.
778	 *
779	 * 1) HWFLOW (RTS) - Turn off the UART's Receive interrupt.
780	 *	This will cause the UART's FIFO to back up, and force
781	 *	the RTS signal to be dropped.
782	 * 2) SWFLOW (IXOFF) - Keep trying to send a stop character to
783	 *	the other side, in hopes it will stop sending data to us.
784	 * 3) NONE - Nothing we can do.  We will simply drop any extra data
785	 *	that gets sent into us when the queue fills up.
786	 */
787	if (qleft < 256) {
788		/* HWFLOW */
789		if (ch->ch_c_cflag & CRTSCTS) {
790			if(!(ch->ch_flags & CH_RECEIVER_OFF)) {
791				bd_ops->disable_receiver(ch);
792				ch->ch_flags |= (CH_RECEIVER_OFF);
793				jsm_printk(READ, INFO, &ch->ch_bd->pci_dev,
794					"Internal queue hit hilevel mark (%d)! Turning off interrupts.\n",
795					qleft);
796			}
797		}
798		/* SWFLOW */
799		else if (ch->ch_c_iflag & IXOFF) {
800			if (ch->ch_stops_sent <= MAX_STOPS_SENT) {
801				bd_ops->send_stop_character(ch);
802				ch->ch_stops_sent++;
803				jsm_printk(READ, INFO, &ch->ch_bd->pci_dev,
804					"Sending stop char! Times sent: %x\n", ch->ch_stops_sent);
 
805			}
806		}
807	}
808
809	/*
810	 * Check to see if we should unenforce flow control because
811	 * ld (or user) finally read enuf data out of our queue.
812	 *
813	 * NOTE: This is done based on what the current flow control of the
814	 * port is set for.
815	 *
816	 * 1) HWFLOW (RTS) - Turn back on the UART's Receive interrupt.
817	 *	This will cause the UART's FIFO to raise RTS back up,
818	 *	which will allow the other side to start sending data again.
819	 * 2) SWFLOW (IXOFF) - Send a start character to
820	 *	the other side, so it will start sending data to us again.
821	 * 3) NONE - Do nothing. Since we didn't do anything to turn off the
822	 *	other side, we don't need to do anything now.
823	 */
824	if (qleft > (RQUEUESIZE / 2)) {
825		/* HWFLOW */
826		if (ch->ch_c_cflag & CRTSCTS) {
827			if (ch->ch_flags & CH_RECEIVER_OFF) {
828				bd_ops->enable_receiver(ch);
829				ch->ch_flags &= ~(CH_RECEIVER_OFF);
830				jsm_printk(READ, INFO, &ch->ch_bd->pci_dev,
831					"Internal queue hit lowlevel mark (%d)! Turning on interrupts.\n",
832					qleft);
833			}
834		}
835		/* SWFLOW */
836		else if (ch->ch_c_iflag & IXOFF && ch->ch_stops_sent) {
837			ch->ch_stops_sent = 0;
838			bd_ops->send_start_character(ch);
839			jsm_printk(READ, INFO, &ch->ch_bd->pci_dev, "Sending start char!\n");
 
840		}
841	}
842}
v4.17
  1// SPDX-License-Identifier: GPL-2.0+
  2/************************************************************************
  3 * Copyright 2003 Digi International (www.digi.com)
  4 *
  5 * Copyright (C) 2004 IBM Corporation. All rights reserved.
  6 *
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  7 * Contact Information:
  8 * Scott H Kilau <Scott_Kilau@digi.com>
  9 * Ananda Venkatarman <mansarov@us.ibm.com>
 10 * Modifications:
 11 * 01/19/06:	changed jsm_input routine to use the dynamically allocated
 12 *		tty_buffer changes. Contributors: Scott Kilau and Ananda V.
 13 ***********************************************************************/
 14#include <linux/tty.h>
 15#include <linux/tty_flip.h>
 16#include <linux/serial_reg.h>
 17#include <linux/delay.h>	/* For udelay */
 18#include <linux/pci.h>
 19#include <linux/slab.h>
 20
 21#include "jsm.h"
 22
 23static DECLARE_BITMAP(linemap, MAXLINES);
 24
 25static void jsm_carrier(struct jsm_channel *ch);
 26
 27static inline int jsm_get_mstat(struct jsm_channel *ch)
 28{
 29	unsigned char mstat;
 30	int result;
 31
 32	jsm_dbg(IOCTL, &ch->ch_bd->pci_dev, "start\n");
 33
 34	mstat = (ch->ch_mostat | ch->ch_mistat);
 35
 36	result = 0;
 37
 38	if (mstat & UART_MCR_DTR)
 39		result |= TIOCM_DTR;
 40	if (mstat & UART_MCR_RTS)
 41		result |= TIOCM_RTS;
 42	if (mstat & UART_MSR_CTS)
 43		result |= TIOCM_CTS;
 44	if (mstat & UART_MSR_DSR)
 45		result |= TIOCM_DSR;
 46	if (mstat & UART_MSR_RI)
 47		result |= TIOCM_RI;
 48	if (mstat & UART_MSR_DCD)
 49		result |= TIOCM_CD;
 50
 51	jsm_dbg(IOCTL, &ch->ch_bd->pci_dev, "finish\n");
 52	return result;
 53}
 54
 55static unsigned int jsm_tty_tx_empty(struct uart_port *port)
 56{
 57	return TIOCSER_TEMT;
 58}
 59
 60/*
 61 * Return modem signals to ld.
 62 */
 63static unsigned int jsm_tty_get_mctrl(struct uart_port *port)
 64{
 65	int result;
 66	struct jsm_channel *channel =
 67		container_of(port, struct jsm_channel, uart_port);
 68
 69	jsm_dbg(IOCTL, &channel->ch_bd->pci_dev, "start\n");
 70
 71	result = jsm_get_mstat(channel);
 72
 73	if (result < 0)
 74		return -ENXIO;
 75
 76	jsm_dbg(IOCTL, &channel->ch_bd->pci_dev, "finish\n");
 77
 78	return result;
 79}
 80
 81/*
 82 * jsm_set_modem_info()
 83 *
 84 * Set modem signals, called by ld.
 85 */
 86static void jsm_tty_set_mctrl(struct uart_port *port, unsigned int mctrl)
 87{
 88	struct jsm_channel *channel =
 89		container_of(port, struct jsm_channel, uart_port);
 90
 91	jsm_dbg(IOCTL, &channel->ch_bd->pci_dev, "start\n");
 92
 93	if (mctrl & TIOCM_RTS)
 94		channel->ch_mostat |= UART_MCR_RTS;
 95	else
 96		channel->ch_mostat &= ~UART_MCR_RTS;
 97
 98	if (mctrl & TIOCM_DTR)
 99		channel->ch_mostat |= UART_MCR_DTR;
100	else
101		channel->ch_mostat &= ~UART_MCR_DTR;
102
103	channel->ch_bd->bd_ops->assert_modem_signals(channel);
104
105	jsm_dbg(IOCTL, &channel->ch_bd->pci_dev, "finish\n");
106	udelay(10);
107}
108
109/*
110 * jsm_tty_write()
111 *
112 * Take data from the user or kernel and send it out to the FEP.
113 * In here exists all the Transparent Print magic as well.
114 */
115static void jsm_tty_write(struct uart_port *port)
116{
117	struct jsm_channel *channel;
118
119	channel = container_of(port, struct jsm_channel, uart_port);
120	channel->ch_bd->bd_ops->copy_data_from_queue_to_uart(channel);
121}
122
123static void jsm_tty_start_tx(struct uart_port *port)
124{
125	struct jsm_channel *channel =
126		container_of(port, struct jsm_channel, uart_port);
127
128	jsm_dbg(IOCTL, &channel->ch_bd->pci_dev, "start\n");
129
130	channel->ch_flags &= ~(CH_STOP);
131	jsm_tty_write(port);
132
133	jsm_dbg(IOCTL, &channel->ch_bd->pci_dev, "finish\n");
134}
135
136static void jsm_tty_stop_tx(struct uart_port *port)
137{
138	struct jsm_channel *channel =
139		container_of(port, struct jsm_channel, uart_port);
140
141	jsm_dbg(IOCTL, &channel->ch_bd->pci_dev, "start\n");
142
143	channel->ch_flags |= (CH_STOP);
144
145	jsm_dbg(IOCTL, &channel->ch_bd->pci_dev, "finish\n");
146}
147
148static void jsm_tty_send_xchar(struct uart_port *port, char ch)
149{
150	unsigned long lock_flags;
151	struct jsm_channel *channel =
152		container_of(port, struct jsm_channel, uart_port);
153	struct ktermios *termios;
154
155	spin_lock_irqsave(&port->lock, lock_flags);
156	termios = &port->state->port.tty->termios;
157	if (ch == termios->c_cc[VSTART])
158		channel->ch_bd->bd_ops->send_start_character(channel);
159
160	if (ch == termios->c_cc[VSTOP])
161		channel->ch_bd->bd_ops->send_stop_character(channel);
162	spin_unlock_irqrestore(&port->lock, lock_flags);
163}
164
165static void jsm_tty_stop_rx(struct uart_port *port)
166{
167	struct jsm_channel *channel =
168		container_of(port, struct jsm_channel, uart_port);
169
170	channel->ch_bd->bd_ops->disable_receiver(channel);
171}
172
 
 
 
 
 
173static void jsm_tty_break(struct uart_port *port, int break_state)
174{
175	unsigned long lock_flags;
176	struct jsm_channel *channel =
177		container_of(port, struct jsm_channel, uart_port);
178
179	spin_lock_irqsave(&port->lock, lock_flags);
180	if (break_state == -1)
181		channel->ch_bd->bd_ops->send_break(channel);
182	else
183		channel->ch_bd->bd_ops->clear_break(channel);
184
185	spin_unlock_irqrestore(&port->lock, lock_flags);
186}
187
188static int jsm_tty_open(struct uart_port *port)
189{
190	struct jsm_board *brd;
191	struct jsm_channel *channel =
192		container_of(port, struct jsm_channel, uart_port);
193	struct ktermios *termios;
194
195	/* Get board pointer from our array of majors we have allocated */
196	brd = channel->ch_bd;
197
198	/*
199	 * Allocate channel buffers for read/write/error.
200	 * Set flag, so we don't get trounced on.
201	 */
202	channel->ch_flags |= (CH_OPENING);
203
204	/* Drop locks, as malloc with GFP_KERNEL can sleep */
205
206	if (!channel->ch_rqueue) {
207		channel->ch_rqueue = kzalloc(RQUEUESIZE, GFP_KERNEL);
208		if (!channel->ch_rqueue) {
209			jsm_dbg(INIT, &channel->ch_bd->pci_dev,
210				"unable to allocate read queue buf\n");
211			return -ENOMEM;
212		}
213	}
214	if (!channel->ch_equeue) {
215		channel->ch_equeue = kzalloc(EQUEUESIZE, GFP_KERNEL);
216		if (!channel->ch_equeue) {
217			jsm_dbg(INIT, &channel->ch_bd->pci_dev,
218				"unable to allocate error queue buf\n");
219			return -ENOMEM;
220		}
221	}
222
223	channel->ch_flags &= ~(CH_OPENING);
224	/*
225	 * Initialize if neither terminal is open.
226	 */
227	jsm_dbg(OPEN, &channel->ch_bd->pci_dev,
228		"jsm_open: initializing channel in open...\n");
229
230	/*
231	 * Flush input queues.
232	 */
233	channel->ch_r_head = channel->ch_r_tail = 0;
234	channel->ch_e_head = channel->ch_e_tail = 0;
235
236	brd->bd_ops->flush_uart_write(channel);
237	brd->bd_ops->flush_uart_read(channel);
238
239	channel->ch_flags = 0;
240	channel->ch_cached_lsr = 0;
241	channel->ch_stops_sent = 0;
242
243	termios = &port->state->port.tty->termios;
244	channel->ch_c_cflag	= termios->c_cflag;
245	channel->ch_c_iflag	= termios->c_iflag;
246	channel->ch_c_oflag	= termios->c_oflag;
247	channel->ch_c_lflag	= termios->c_lflag;
248	channel->ch_startc	= termios->c_cc[VSTART];
249	channel->ch_stopc	= termios->c_cc[VSTOP];
250
251	/* Tell UART to init itself */
252	brd->bd_ops->uart_init(channel);
253
254	/*
255	 * Run param in case we changed anything
256	 */
257	brd->bd_ops->param(channel);
258
259	jsm_carrier(channel);
260
261	channel->ch_open_count++;
262
263	jsm_dbg(OPEN, &channel->ch_bd->pci_dev, "finish\n");
264	return 0;
265}
266
267static void jsm_tty_close(struct uart_port *port)
268{
269	struct jsm_board *bd;
270	struct jsm_channel *channel =
271		container_of(port, struct jsm_channel, uart_port);
272
273	jsm_dbg(CLOSE, &channel->ch_bd->pci_dev, "start\n");
274
275	bd = channel->ch_bd;
 
276
277	channel->ch_flags &= ~(CH_STOPI);
278
279	channel->ch_open_count--;
280
281	/*
282	 * If we have HUPCL set, lower DTR and RTS
283	 */
284	if (channel->ch_c_cflag & HUPCL) {
285		jsm_dbg(CLOSE, &channel->ch_bd->pci_dev,
286			"Close. HUPCL set, dropping DTR/RTS\n");
287
288		/* Drop RTS/DTR */
289		channel->ch_mostat &= ~(UART_MCR_DTR | UART_MCR_RTS);
290		bd->bd_ops->assert_modem_signals(channel);
291	}
292
293	/* Turn off UART interrupts for this port */
294	channel->ch_bd->bd_ops->uart_off(channel);
295
296	jsm_dbg(CLOSE, &channel->ch_bd->pci_dev, "finish\n");
297}
298
299static void jsm_tty_set_termios(struct uart_port *port,
300				 struct ktermios *termios,
301				 struct ktermios *old_termios)
302{
303	unsigned long lock_flags;
304	struct jsm_channel *channel =
305		container_of(port, struct jsm_channel, uart_port);
306
307	spin_lock_irqsave(&port->lock, lock_flags);
308	channel->ch_c_cflag	= termios->c_cflag;
309	channel->ch_c_iflag	= termios->c_iflag;
310	channel->ch_c_oflag	= termios->c_oflag;
311	channel->ch_c_lflag	= termios->c_lflag;
312	channel->ch_startc	= termios->c_cc[VSTART];
313	channel->ch_stopc	= termios->c_cc[VSTOP];
314
315	channel->ch_bd->bd_ops->param(channel);
316	jsm_carrier(channel);
317	spin_unlock_irqrestore(&port->lock, lock_flags);
318}
319
320static const char *jsm_tty_type(struct uart_port *port)
321{
322	return "jsm";
323}
324
325static void jsm_tty_release_port(struct uart_port *port)
326{
327}
328
329static int jsm_tty_request_port(struct uart_port *port)
330{
331	return 0;
332}
333
334static void jsm_config_port(struct uart_port *port, int flags)
335{
336	port->type = PORT_JSM;
337}
338
339static const struct uart_ops jsm_ops = {
340	.tx_empty	= jsm_tty_tx_empty,
341	.set_mctrl	= jsm_tty_set_mctrl,
342	.get_mctrl	= jsm_tty_get_mctrl,
343	.stop_tx	= jsm_tty_stop_tx,
344	.start_tx	= jsm_tty_start_tx,
345	.send_xchar	= jsm_tty_send_xchar,
346	.stop_rx	= jsm_tty_stop_rx,
 
347	.break_ctl	= jsm_tty_break,
348	.startup	= jsm_tty_open,
349	.shutdown	= jsm_tty_close,
350	.set_termios	= jsm_tty_set_termios,
351	.type		= jsm_tty_type,
352	.release_port	= jsm_tty_release_port,
353	.request_port	= jsm_tty_request_port,
354	.config_port	= jsm_config_port,
355};
356
357/*
358 * jsm_tty_init()
359 *
360 * Init the tty subsystem.  Called once per board after board has been
361 * downloaded and init'ed.
362 */
363int jsm_tty_init(struct jsm_board *brd)
364{
365	int i;
366	void __iomem *vaddr;
367	struct jsm_channel *ch;
368
369	if (!brd)
370		return -ENXIO;
371
372	jsm_dbg(INIT, &brd->pci_dev, "start\n");
373
374	/*
375	 * Initialize board structure elements.
376	 */
377
378	brd->nasync = brd->maxports;
379
380	/*
381	 * Allocate channel memory that might not have been allocated
382	 * when the driver was first loaded.
383	 */
384	for (i = 0; i < brd->nasync; i++) {
385		if (!brd->channels[i]) {
386
387			/*
388			 * Okay to malloc with GFP_KERNEL, we are not at
389			 * interrupt context, and there are no locks held.
390			 */
391			brd->channels[i] = kzalloc(sizeof(struct jsm_channel), GFP_KERNEL);
392			if (!brd->channels[i]) {
393				jsm_dbg(CORE, &brd->pci_dev,
394					"%s:%d Unable to allocate memory for channel struct\n",
395					__FILE__, __LINE__);
396			}
397		}
398	}
399
400	ch = brd->channels[0];
401	vaddr = brd->re_map_membase;
402
403	/* Set up channel variables */
404	for (i = 0; i < brd->nasync; i++, ch = brd->channels[i]) {
405
406		if (!brd->channels[i])
407			continue;
408
409		spin_lock_init(&ch->ch_lock);
410
411		if (brd->bd_uart_offset == 0x200)
412			ch->ch_neo_uart =  vaddr + (brd->bd_uart_offset * i);
413		else
414			ch->ch_cls_uart =  vaddr + (brd->bd_uart_offset * i);
415
416		ch->ch_bd = brd;
417		ch->ch_portnum = i;
418
419		/* .25 second delay */
420		ch->ch_close_delay = 250;
421
422		init_waitqueue_head(&ch->ch_flags_wait);
423	}
424
425	jsm_dbg(INIT, &brd->pci_dev, "finish\n");
426	return 0;
427}
428
429int jsm_uart_port_init(struct jsm_board *brd)
430{
431	int i, rc;
432	unsigned int line;
433	struct jsm_channel *ch;
434
435	if (!brd)
436		return -ENXIO;
437
438	jsm_dbg(INIT, &brd->pci_dev, "start\n");
439
440	/*
441	 * Initialize board structure elements.
442	 */
443
444	brd->nasync = brd->maxports;
445
446	/* Set up channel variables */
447	for (i = 0; i < brd->nasync; i++, ch = brd->channels[i]) {
448
449		if (!brd->channels[i])
450			continue;
451
452		brd->channels[i]->uart_port.irq = brd->irq;
453		brd->channels[i]->uart_port.uartclk = 14745600;
454		brd->channels[i]->uart_port.type = PORT_JSM;
455		brd->channels[i]->uart_port.iotype = UPIO_MEM;
456		brd->channels[i]->uart_port.membase = brd->re_map_membase;
457		brd->channels[i]->uart_port.fifosize = 16;
458		brd->channels[i]->uart_port.ops = &jsm_ops;
459		line = find_first_zero_bit(linemap, MAXLINES);
460		if (line >= MAXLINES) {
461			printk(KERN_INFO "jsm: linemap is full, added device failed\n");
462			continue;
463		} else
464			set_bit(line, linemap);
465		brd->channels[i]->uart_port.line = line;
466		rc = uart_add_one_port(&jsm_uart_driver, &brd->channels[i]->uart_port);
467		if (rc) {
468			printk(KERN_INFO "jsm: Port %d failed. Aborting...\n", i);
469			return rc;
470		} else
 
471			printk(KERN_INFO "jsm: Port %d added\n", i);
472	}
473
474	jsm_dbg(INIT, &brd->pci_dev, "finish\n");
475	return 0;
476}
477
478int jsm_remove_uart_port(struct jsm_board *brd)
479{
480	int i;
481	struct jsm_channel *ch;
482
483	if (!brd)
484		return -ENXIO;
485
486	jsm_dbg(INIT, &brd->pci_dev, "start\n");
487
488	/*
489	 * Initialize board structure elements.
490	 */
491
492	brd->nasync = brd->maxports;
493
494	/* Set up channel variables */
495	for (i = 0; i < brd->nasync; i++) {
496
497		if (!brd->channels[i])
498			continue;
499
500		ch = brd->channels[i];
501
502		clear_bit(ch->uart_port.line, linemap);
503		uart_remove_one_port(&jsm_uart_driver, &brd->channels[i]->uart_port);
504	}
505
506	jsm_dbg(INIT, &brd->pci_dev, "finish\n");
507	return 0;
508}
509
510void jsm_input(struct jsm_channel *ch)
511{
512	struct jsm_board *bd;
513	struct tty_struct *tp;
514	struct tty_port *port;
515	u32 rmask;
516	u16 head;
517	u16 tail;
518	int data_len;
519	unsigned long lock_flags;
520	int len = 0;
 
521	int s = 0;
522	int i = 0;
523
524	jsm_dbg(READ, &ch->ch_bd->pci_dev, "start\n");
 
 
 
525
526	port = &ch->uart_port.state->port;
527	tp = port->tty;
528
529	bd = ch->ch_bd;
530	if (!bd)
531		return;
532
533	spin_lock_irqsave(&ch->ch_lock, lock_flags);
534
535	/*
536	 *Figure the number of characters in the buffer.
537	 *Exit immediately if none.
538	 */
539
540	rmask = RQUEUEMASK;
541
542	head = ch->ch_r_head & rmask;
543	tail = ch->ch_r_tail & rmask;
544
545	data_len = (head - tail) & rmask;
546	if (data_len == 0) {
547		spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
548		return;
549	}
550
551	jsm_dbg(READ, &ch->ch_bd->pci_dev, "start\n");
552
553	/*
554	 *If the device is not open, or CREAD is off, flush
555	 *input data and return immediately.
556	 */
557	if (!tp || !C_CREAD(tp)) {
 
558
559		jsm_dbg(READ, &ch->ch_bd->pci_dev,
560			"input. dropping %d bytes on port %d...\n",
561			data_len, ch->ch_portnum);
562		ch->ch_r_head = tail;
563
564		/* Force queue flow control to be released, if needed */
565		jsm_check_queue_flow_control(ch);
566
567		spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
568		return;
569	}
570
571	/*
572	 * If we are throttled, simply don't read any data.
573	 */
574	if (ch->ch_flags & CH_STOPI) {
575		spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
576		jsm_dbg(READ, &ch->ch_bd->pci_dev,
577			"Port %d throttled, not reading any data. head: %x tail: %x\n",
578			ch->ch_portnum, head, tail);
579		return;
580	}
581
582	jsm_dbg(READ, &ch->ch_bd->pci_dev, "start 2\n");
 
 
 
 
 
 
583
584	len = tty_buffer_request_room(port, data_len);
 
585
586	/*
587	 * len now contains the most amount of data we can copy,
588	 * bounded either by the flip buffer size or the amount
589	 * of data the card actually has pending...
590	 */
591	while (len) {
592		s = ((head >= tail) ? head : RQUEUESIZE) - tail;
593		s = min(s, len);
594
595		if (s <= 0)
596			break;
597
598			/*
599			 * If conditions are such that ld needs to see all
600			 * UART errors, we will have to walk each character
601			 * and error byte and send them to the buffer one at
602			 * a time.
603			 */
604
605		if (I_PARMRK(tp) || I_BRKINT(tp) || I_INPCK(tp)) {
606			for (i = 0; i < s; i++) {
607				/*
608				 * Give the Linux ld the flags in the
609				 * format it likes.
610				 */
611				if (*(ch->ch_equeue +tail +i) & UART_LSR_BI)
612					tty_insert_flip_char(port, *(ch->ch_rqueue +tail +i),  TTY_BREAK);
613				else if (*(ch->ch_equeue +tail +i) & UART_LSR_PE)
614					tty_insert_flip_char(port, *(ch->ch_rqueue +tail +i), TTY_PARITY);
615				else if (*(ch->ch_equeue +tail +i) & UART_LSR_FE)
616					tty_insert_flip_char(port, *(ch->ch_rqueue +tail +i), TTY_FRAME);
617				else
618					tty_insert_flip_char(port, *(ch->ch_rqueue +tail +i), TTY_NORMAL);
619			}
620		} else {
621			tty_insert_flip_string(port, ch->ch_rqueue + tail, s);
622		}
623		tail += s;
624		len -= s;
625		/* Flip queue if needed */
626		tail &= rmask;
627	}
628
629	ch->ch_r_tail = tail & rmask;
630	ch->ch_e_tail = tail & rmask;
631	jsm_check_queue_flow_control(ch);
632	spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
633
634	/* Tell the tty layer its okay to "eat" the data now */
635	tty_flip_buffer_push(port);
636
637	jsm_dbg(IOCTL, &ch->ch_bd->pci_dev, "finish\n");
638}
639
640static void jsm_carrier(struct jsm_channel *ch)
641{
642	struct jsm_board *bd;
643
644	int virt_carrier = 0;
645	int phys_carrier = 0;
646
647	jsm_dbg(CARR, &ch->ch_bd->pci_dev, "start\n");
 
 
648
649	bd = ch->ch_bd;
 
650	if (!bd)
651		return;
652
653	if (ch->ch_mistat & UART_MSR_DCD) {
654		jsm_dbg(CARR, &ch->ch_bd->pci_dev, "mistat: %x D_CD: %x\n",
655			ch->ch_mistat, ch->ch_mistat & UART_MSR_DCD);
656		phys_carrier = 1;
657	}
658
659	if (ch->ch_c_cflag & CLOCAL)
660		virt_carrier = 1;
661
662	jsm_dbg(CARR, &ch->ch_bd->pci_dev, "DCD: physical: %d virt: %d\n",
663		phys_carrier, virt_carrier);
664
665	/*
666	 * Test for a VIRTUAL carrier transition to HIGH.
667	 */
668	if (((ch->ch_flags & CH_FCAR) == 0) && (virt_carrier == 1)) {
669
670		/*
671		 * When carrier rises, wake any threads waiting
672		 * for carrier in the open routine.
673		 */
674
675		jsm_dbg(CARR, &ch->ch_bd->pci_dev, "carrier: virt DCD rose\n");
 
676
677		if (waitqueue_active(&(ch->ch_flags_wait)))
678			wake_up_interruptible(&ch->ch_flags_wait);
679	}
680
681	/*
682	 * Test for a PHYSICAL carrier transition to HIGH.
683	 */
684	if (((ch->ch_flags & CH_CD) == 0) && (phys_carrier == 1)) {
685
686		/*
687		 * When carrier rises, wake any threads waiting
688		 * for carrier in the open routine.
689		 */
690
691		jsm_dbg(CARR, &ch->ch_bd->pci_dev,
692			"carrier: physical DCD rose\n");
693
694		if (waitqueue_active(&(ch->ch_flags_wait)))
695			wake_up_interruptible(&ch->ch_flags_wait);
696	}
697
698	/*
699	 *  Test for a PHYSICAL transition to low, so long as we aren't
700	 *  currently ignoring physical transitions (which is what "virtual
701	 *  carrier" indicates).
702	 *
703	 *  The transition of the virtual carrier to low really doesn't
704	 *  matter... it really only means "ignore carrier state", not
705	 *  "make pretend that carrier is there".
706	 */
707	if ((virt_carrier == 0) && ((ch->ch_flags & CH_CD) != 0)
708			&& (phys_carrier == 0)) {
709		/*
710		 *	When carrier drops:
711		 *
712		 *	Drop carrier on all open units.
713		 *
714		 *	Flush queues, waking up any task waiting in the
715		 *	line discipline.
716		 *
717		 *	Send a hangup to the control terminal.
718		 *
719		 *	Enable all select calls.
720		 */
721		if (waitqueue_active(&(ch->ch_flags_wait)))
722			wake_up_interruptible(&ch->ch_flags_wait);
723	}
724
725	/*
726	 *  Make sure that our cached values reflect the current reality.
727	 */
728	if (virt_carrier == 1)
729		ch->ch_flags |= CH_FCAR;
730	else
731		ch->ch_flags &= ~CH_FCAR;
732
733	if (phys_carrier == 1)
734		ch->ch_flags |= CH_CD;
735	else
736		ch->ch_flags &= ~CH_CD;
737}
738
739
740void jsm_check_queue_flow_control(struct jsm_channel *ch)
741{
742	struct board_ops *bd_ops = ch->ch_bd->bd_ops;
743	int qleft;
744
745	/* Store how much space we have left in the queue */
746	if ((qleft = ch->ch_r_tail - ch->ch_r_head - 1) < 0)
747		qleft += RQUEUEMASK + 1;
748
749	/*
750	 * Check to see if we should enforce flow control on our queue because
751	 * the ld (or user) isn't reading data out of our queue fast enuf.
752	 *
753	 * NOTE: This is done based on what the current flow control of the
754	 * port is set for.
755	 *
756	 * 1) HWFLOW (RTS) - Turn off the UART's Receive interrupt.
757	 *	This will cause the UART's FIFO to back up, and force
758	 *	the RTS signal to be dropped.
759	 * 2) SWFLOW (IXOFF) - Keep trying to send a stop character to
760	 *	the other side, in hopes it will stop sending data to us.
761	 * 3) NONE - Nothing we can do.  We will simply drop any extra data
762	 *	that gets sent into us when the queue fills up.
763	 */
764	if (qleft < 256) {
765		/* HWFLOW */
766		if (ch->ch_c_cflag & CRTSCTS) {
767			if (!(ch->ch_flags & CH_RECEIVER_OFF)) {
768				bd_ops->disable_receiver(ch);
769				ch->ch_flags |= (CH_RECEIVER_OFF);
770				jsm_dbg(READ, &ch->ch_bd->pci_dev,
771					"Internal queue hit hilevel mark (%d)! Turning off interrupts\n",
772					qleft);
773			}
774		}
775		/* SWFLOW */
776		else if (ch->ch_c_iflag & IXOFF) {
777			if (ch->ch_stops_sent <= MAX_STOPS_SENT) {
778				bd_ops->send_stop_character(ch);
779				ch->ch_stops_sent++;
780				jsm_dbg(READ, &ch->ch_bd->pci_dev,
781					"Sending stop char! Times sent: %x\n",
782					ch->ch_stops_sent);
783			}
784		}
785	}
786
787	/*
788	 * Check to see if we should unenforce flow control because
789	 * ld (or user) finally read enuf data out of our queue.
790	 *
791	 * NOTE: This is done based on what the current flow control of the
792	 * port is set for.
793	 *
794	 * 1) HWFLOW (RTS) - Turn back on the UART's Receive interrupt.
795	 *	This will cause the UART's FIFO to raise RTS back up,
796	 *	which will allow the other side to start sending data again.
797	 * 2) SWFLOW (IXOFF) - Send a start character to
798	 *	the other side, so it will start sending data to us again.
799	 * 3) NONE - Do nothing. Since we didn't do anything to turn off the
800	 *	other side, we don't need to do anything now.
801	 */
802	if (qleft > (RQUEUESIZE / 2)) {
803		/* HWFLOW */
804		if (ch->ch_c_cflag & CRTSCTS) {
805			if (ch->ch_flags & CH_RECEIVER_OFF) {
806				bd_ops->enable_receiver(ch);
807				ch->ch_flags &= ~(CH_RECEIVER_OFF);
808				jsm_dbg(READ, &ch->ch_bd->pci_dev,
809					"Internal queue hit lowlevel mark (%d)! Turning on interrupts\n",
810					qleft);
811			}
812		}
813		/* SWFLOW */
814		else if (ch->ch_c_iflag & IXOFF && ch->ch_stops_sent) {
815			ch->ch_stops_sent = 0;
816			bd_ops->send_start_character(ch);
817			jsm_dbg(READ, &ch->ch_bd->pci_dev,
818				"Sending start char!\n");
819		}
820	}
821}