1/*
2 * pc300_tty.c	Cyclades-PC300(tm) TTY Driver.
3 *
4 * Author:	Regina Kodato <reginak@cyclades.com>
5 *
6 * Copyright:	(c) 1999-2002 Cyclades Corp.
7 *
8 *	This program is free software; you can redistribute it and/or
9 *  modify it under the terms of the GNU General Public License
10 *  as published by the Free Software Foundation; either version
11 *  2 of the License, or (at your option) any later version.
12 *
13 *  $Log: pc300_tty.c,v $
14 *  Revision 3.7  2002/03/07 14:17:09  henrique
15 *  License data fixed
16 *
17 *  Revision 3.6  2001/12/10 12:29:42  regina
18 *  Fix the MLPPP bug
19 *
20 *  Revision 3.5  2001/10/31 11:20:05  regina
21 *  automatic pppd starts
22 *
23 *  Revision 3.4  2001/08/06 12:01:51  regina
24 *  problem in DSR_DE bit
25 *
26 *  Revision 3.3  2001/07/26 22:58:41  regina
27 *  update EDA value
28 *
29 *  Revision 3.2  2001/07/12 13:11:20  regina
30 *  bug fix - DCD-OFF in pc300 tty driver
31 *
32 *	DMA transmission bug fix
33 *
34 *  Revision 3.1  2001/06/22 13:13:02  regina
35 *  MLPPP implementation
36 *
37 */
38
39#include <linux/module.h>
40#include <linux/kernel.h>
41#include <linux/errno.h>
42#include <linux/string.h>
43#include <linux/init.h>
44#include <linux/netdevice.h>
45#include <linux/spinlock.h>
46#include <linux/slab.h>
47#include <linux/if.h>
48#include <linux/skbuff.h>
49/* TTY includes */
50#include <linux/tty.h>
51#include <linux/tty_flip.h>
52#include <linux/serial.h>
53
54#include <asm/io.h>
55#include <asm/uaccess.h>
56
57#include "pc300.h"
58
59/* defines and macros */
60/* TTY Global definitions */
61#define	CPC_TTY_NPORTS	8	/* maximum number of the sync tty connections */
62#define	CPC_TTY_MAJOR	CYCLADES_MAJOR
63#define CPC_TTY_MINOR_START	240	/* minor of the first PC300 interface */
64
65#define CPC_TTY_MAX_MTU	2000
66
67/* tty interface state */
68#define	CPC_TTY_ST_IDLE	0
69#define CPC_TTY_ST_INIT	1	/* configured with MLPPP and up */
70#define CPC_TTY_ST_OPEN	2	/* opened by application */
71
72#define	CPC_TTY_LOCK(card,flags)\
73	do {\
74		spin_lock_irqsave(&card->card_lock, flags);	\
75	} while (0)
76
77#define CPC_TTY_UNLOCK(card,flags)	\
78	do {\
79		spin_unlock_irqrestore(&card->card_lock, flags);	\
80	} while (0)
81
82//#define	CPC_TTY_DBG(format,a...)	printk(format,##a)
83#define	CPC_TTY_DBG(format,a...)
84
85/* data structures */
86typedef struct _st_cpc_rx_buf {
87	struct _st_cpc_rx_buf	*next;
88	int		size;
89	unsigned char	data[1];
90} st_cpc_rx_buf;
91
92struct st_cpc_rx_list {
93	st_cpc_rx_buf	*first;
94	st_cpc_rx_buf	*last;
95};
96
97typedef	struct _st_cpc_tty_area {
98	int		state;		/* state of the TTY interface */
99	int		num_open;
100	unsigned int 	tty_minor;	/* minor this interface */
101	volatile struct st_cpc_rx_list buf_rx;	/* ptr. to reception buffer */
102	unsigned char*	buf_tx;		/* ptr. to transmission buffer */
103	pc300dev_t*	pc300dev;	/* ptr. to info struct in PC300 driver */
104	unsigned char	name[20];	/* interf. name + "-tty" */
105	struct tty_struct *tty;
106	struct work_struct tty_tx_work; /* tx work - tx interrupt */
107	struct work_struct tty_rx_work; /* rx work - rx interrupt */
108	} st_cpc_tty_area;
109
110/* TTY data structures */
111static struct tty_driver serial_drv;
112
113/* local variables */
114static st_cpc_tty_area	cpc_tty_area[CPC_TTY_NPORTS];
115
116static int cpc_tty_cnt = 0;	/* number of intrfaces configured with MLPPP */
117static int cpc_tty_unreg_flag = 0;
118
119/* TTY functions prototype */
120static int cpc_tty_open(struct tty_struct *tty, struct file *flip);
121static void cpc_tty_close(struct tty_struct *tty, struct file *flip);
122static int cpc_tty_write(struct tty_struct *tty, const unsigned char *buf, int count);
123static int cpc_tty_write_room(struct tty_struct *tty);
124static int cpc_tty_chars_in_buffer(struct tty_struct *tty);
125static void cpc_tty_flush_buffer(struct tty_struct *tty);
126static void cpc_tty_hangup(struct tty_struct *tty);
127static void cpc_tty_rx_work(struct work_struct *work);
128static void cpc_tty_tx_work(struct work_struct *work);
129static int cpc_tty_send_to_card(pc300dev_t *dev,void *buf, int len);
130static void cpc_tty_trace(pc300dev_t *dev, char* buf, int len, char rxtx);
131static void cpc_tty_signal_off(pc300dev_t *pc300dev, unsigned char);
132static void cpc_tty_signal_on(pc300dev_t *pc300dev, unsigned char);
133
134static int pc300_tiocmset(struct tty_struct *, unsigned int, unsigned int);
135static int pc300_tiocmget(struct tty_struct *);
136
137/* functions called by PC300 driver */
138void cpc_tty_init(pc300dev_t *dev);
139void cpc_tty_unregister_service(pc300dev_t *pc300dev);
140void cpc_tty_receive(pc300dev_t *pc300dev);
141void cpc_tty_trigger_poll(pc300dev_t *pc300dev);
142
143/*
144 * PC300 TTY clear "signal"
145 */
146static void cpc_tty_signal_off(pc300dev_t *pc300dev, unsigned char signal)
147{
148	pc300ch_t *pc300chan = (pc300ch_t *)pc300dev->chan;
149	pc300_t *card = (pc300_t *) pc300chan->card;
150	int ch = pc300chan->channel;
151	unsigned long flags;
152
153	CPC_TTY_DBG("%s-tty: Clear signal %x\n",
154		pc300dev->dev->name, signal);
155	CPC_TTY_LOCK(card, flags);
156	cpc_writeb(card->hw.scabase + M_REG(CTL,ch),
157		cpc_readb(card->hw.scabase+M_REG(CTL,ch))& signal);
158	CPC_TTY_UNLOCK(card,flags);
159}
160
161/*
162 * PC300 TTY set "signal" to ON
163 */
164static void cpc_tty_signal_on(pc300dev_t *pc300dev, unsigned char signal)
165{
166	pc300ch_t *pc300chan = (pc300ch_t *)pc300dev->chan;
167	pc300_t *card = (pc300_t *) pc300chan->card;
168	int ch = pc300chan->channel;
169	unsigned long flags;
170
171	CPC_TTY_DBG("%s-tty: Set signal %x\n",
172		pc300dev->dev->name, signal);
173	CPC_TTY_LOCK(card, flags);
174	cpc_writeb(card->hw.scabase + M_REG(CTL,ch),
175		cpc_readb(card->hw.scabase+M_REG(CTL,ch))& ~signal);
176	CPC_TTY_UNLOCK(card,flags);
177}
178
179
180static const struct tty_operations pc300_ops = {
181	.open = cpc_tty_open,
182	.close = cpc_tty_close,
183	.write = cpc_tty_write,
184	.write_room = cpc_tty_write_room,
185	.chars_in_buffer = cpc_tty_chars_in_buffer,
186	.tiocmset = pc300_tiocmset,
187	.tiocmget = pc300_tiocmget,
188	.flush_buffer = cpc_tty_flush_buffer,
189	.hangup = cpc_tty_hangup,
190};
191
192
193/*
194 * PC300 TTY initialization routine
195 *
196 * This routine is called by the PC300 driver during board configuration
197 * (ioctl=SIOCSP300CONF). At this point the adapter is completely
198 * initialized.
199 * o verify kernel version (only 2.4.x)
200 * o register TTY driver
201 * o init cpc_tty_area struct
202 */
203void cpc_tty_init(pc300dev_t *pc300dev)
204{
205	unsigned long port;
206	int aux;
207	st_cpc_tty_area * cpc_tty;
208
209	/* hdlcX - X=interface number */
210	port = pc300dev->dev->name[4] - '0';
211	if (port >= CPC_TTY_NPORTS) {
212		printk("%s-tty: invalid interface selected (0-%i): %li",
213			pc300dev->dev->name,
214			CPC_TTY_NPORTS-1,port);
215		return;
216	}
217
218	if (cpc_tty_cnt == 0) { /* first TTY connection -> register driver */
219		CPC_TTY_DBG("%s-tty: driver init, major:%i, minor range:%i=%i\n",
220			pc300dev->dev->name,
221			CPC_TTY_MAJOR, CPC_TTY_MINOR_START,
222			CPC_TTY_MINOR_START+CPC_TTY_NPORTS);
223		/* initialize tty driver struct */
224		memset(&serial_drv,0,sizeof(struct tty_driver));
225		serial_drv.magic = TTY_DRIVER_MAGIC;
226		serial_drv.owner = THIS_MODULE;
227		serial_drv.driver_name = "pc300_tty";
228		serial_drv.name = "ttyCP";
229		serial_drv.major = CPC_TTY_MAJOR;
230		serial_drv.minor_start = CPC_TTY_MINOR_START;
231		serial_drv.num = CPC_TTY_NPORTS;
232		serial_drv.type = TTY_DRIVER_TYPE_SERIAL;
233		serial_drv.subtype = SERIAL_TYPE_NORMAL;
234
235		serial_drv.init_termios = tty_std_termios;
236		serial_drv.init_termios.c_cflag = B9600|CS8|CREAD|HUPCL|CLOCAL;
237		serial_drv.flags = TTY_DRIVER_REAL_RAW;
238
239		/* interface routines from the upper tty layer to the tty driver */
240		tty_set_operations(&serial_drv, &pc300_ops);
241
242		/* register the TTY driver */
243		if (tty_register_driver(&serial_drv)) {
244			printk("%s-tty: Failed to register serial driver! ",
245				pc300dev->dev->name);
246		   	return;
247		}
248
249		memset((void *)cpc_tty_area, 0,
250								sizeof(st_cpc_tty_area) * CPC_TTY_NPORTS);
251	}
252
253	cpc_tty = &cpc_tty_area[port];
254
255	if (cpc_tty->state != CPC_TTY_ST_IDLE) {
256		CPC_TTY_DBG("%s-tty: TTY port %i, already in use.\n",
257				pc300dev->dev->name, port);
258		return;
259	}
260
261	cpc_tty_cnt++;
262	cpc_tty->state = CPC_TTY_ST_INIT;
263	cpc_tty->num_open= 0;
264	cpc_tty->tty_minor = port + CPC_TTY_MINOR_START;
265	cpc_tty->pc300dev = pc300dev;
266
267	INIT_WORK(&cpc_tty->tty_tx_work, cpc_tty_tx_work);
268	INIT_WORK(&cpc_tty->tty_rx_work, cpc_tty_rx_work);
269
270	cpc_tty->buf_rx.first = cpc_tty->buf_rx.last = NULL;
271
272	pc300dev->cpc_tty = (void *)cpc_tty;
273
274	aux = strlen(pc300dev->dev->name);
275	memcpy(cpc_tty->name, pc300dev->dev->name, aux);
276	memcpy(&cpc_tty->name[aux], "-tty", 5);
277
278	cpc_open(pc300dev->dev);
279	cpc_tty_signal_off(pc300dev, CTL_DTR);
280
281	CPC_TTY_DBG("%s: Initializing TTY Sync Driver, tty major#%d minor#%i\n",
282			cpc_tty->name,CPC_TTY_MAJOR,cpc_tty->tty_minor);
283	return;
284}
285
286/*
287 * PC300 TTY OPEN routine
288 *
289 * This routine is called by the tty driver to open the interface
290 * o verify minor
291 * o allocate buffer to Rx and Tx
292 */
293static int cpc_tty_open(struct tty_struct *tty, struct file *flip)
294{
295	int port ;
296	st_cpc_tty_area *cpc_tty;
297
298	if (!tty) {
299		return -ENODEV;
300	}
301
302	port = tty->index;
303
304	if ((port < 0) || (port >= CPC_TTY_NPORTS)){
305		CPC_TTY_DBG("pc300_tty: open invalid port %d\n", port);
306		return -ENODEV;
307	}
308
309	cpc_tty = &cpc_tty_area[port];
310
311	if (cpc_tty->state == CPC_TTY_ST_IDLE){
312		CPC_TTY_DBG("%s: open - invalid interface, port=%d\n",
313					cpc_tty->name, tty->index);
314		return -ENODEV;
315	}
316
317	if (cpc_tty->num_open == 0) { /* first open of this tty */
318		if (!cpc_tty_area[port].buf_tx){
319			cpc_tty_area[port].buf_tx = kmalloc(CPC_TTY_MAX_MTU,GFP_KERNEL);
320			if (!cpc_tty_area[port].buf_tx) {
321				CPC_TTY_DBG("%s: error in memory allocation\n",cpc_tty->name);
322				return -ENOMEM;
323			}
324		}
325
326		if (cpc_tty_area[port].buf_rx.first) {
327			unsigned char * aux;
328			while (cpc_tty_area[port].buf_rx.first) {
329				aux = (unsigned char *)cpc_tty_area[port].buf_rx.first;
330				cpc_tty_area[port].buf_rx.first = cpc_tty_area[port].buf_rx.first->next;
331				kfree(aux);
332			}
333			cpc_tty_area[port].buf_rx.first = NULL;
334			cpc_tty_area[port].buf_rx.last = NULL;
335		}
336
337		cpc_tty_area[port].state = CPC_TTY_ST_OPEN;
338		cpc_tty_area[port].tty = tty;
339		tty->driver_data = &cpc_tty_area[port];
340
341		cpc_tty_signal_on(cpc_tty->pc300dev, CTL_DTR);
342	}
343
344	cpc_tty->num_open++;
345
346	CPC_TTY_DBG("%s: opening TTY driver\n", cpc_tty->name);
347
348	/* avisar driver PC300 */
349	return 0;
350}
351
352/*
353 * PC300 TTY CLOSE routine
354 *
355 * This routine is called by the tty driver to close the interface
356 * o call close channel in PC300 driver (cpc_closech)
357 * o free Rx and Tx buffers
358 */
359
360static void cpc_tty_close(struct tty_struct *tty, struct file *flip)
361{
362	st_cpc_tty_area    *cpc_tty;
363	unsigned long flags;
364	int res;
365
366	if (!tty || !tty->driver_data ) {
367		CPC_TTY_DBG("hdlx-tty: no TTY in close\n");
368		return;
369	}
370
371	cpc_tty = (st_cpc_tty_area *) tty->driver_data;
372
373	if ((cpc_tty->tty != tty)|| (cpc_tty->state != CPC_TTY_ST_OPEN)) {
374		CPC_TTY_DBG("%s: TTY is not opened\n",cpc_tty->name);
375		return;
376	}
377
378	if (!cpc_tty->num_open) {
379		CPC_TTY_DBG("%s: TTY is closed\n",cpc_tty->name);
380		return;
381	}
382
383	if (--cpc_tty->num_open > 0) {
384		CPC_TTY_DBG("%s: TTY closed\n",cpc_tty->name);
385		return;
386	}
387
388	cpc_tty_signal_off(cpc_tty->pc300dev, CTL_DTR);
389
390	CPC_TTY_LOCK(cpc_tty->pc300dev->chan->card, flags);  /* lock irq */
391	cpc_tty->tty = NULL;
392	cpc_tty->state = CPC_TTY_ST_INIT;
393	CPC_TTY_UNLOCK(cpc_tty->pc300dev->chan->card, flags); /* unlock irq */
394
395	if (cpc_tty->buf_rx.first) {
396		unsigned char * aux;
397		while (cpc_tty->buf_rx.first) {
398			aux = (unsigned char *)cpc_tty->buf_rx.first;
399			cpc_tty->buf_rx.first = cpc_tty->buf_rx.first->next;
400			kfree(aux);
401		}
402		cpc_tty->buf_rx.first = NULL;
403		cpc_tty->buf_rx.last = NULL;
404	}
405
406	kfree(cpc_tty->buf_tx);
407	cpc_tty->buf_tx = NULL;
408
409	CPC_TTY_DBG("%s: TTY closed\n",cpc_tty->name);
410
411	if (!serial_drv.refcount && cpc_tty_unreg_flag) {
412		cpc_tty_unreg_flag = 0;
413		CPC_TTY_DBG("%s: unregister the tty driver\n", cpc_tty->name);
414		if ((res=tty_unregister_driver(&serial_drv))) {
415			CPC_TTY_DBG("%s: ERROR ->unregister the tty driver error=%d\n",
416							cpc_tty->name,res);
417		}
418	}
419	return;
420}
421
422/*
423 * PC300 TTY WRITE routine
424 *
425 * This routine is called by the tty driver to write a series of characters
426 * to the tty device. The characters may come from user or kernel space.
427 * o verify the DCD signal
428 * o send characters to board and start the transmission
429 */
430static int cpc_tty_write(struct tty_struct *tty, const unsigned char *buf, int count)
431{
432	st_cpc_tty_area    *cpc_tty;
433	pc300ch_t *pc300chan;
434	pc300_t *card;
435	int ch;
436	unsigned long flags;
437	struct net_device_stats *stats;
438
439	if (!tty || !tty->driver_data ) {
440		CPC_TTY_DBG("hdlcX-tty: no TTY in write\n");
441		return -ENODEV;
442	}
443
444	cpc_tty = (st_cpc_tty_area *) tty->driver_data;
445
446	if ((cpc_tty->tty != tty) ||  (cpc_tty->state != CPC_TTY_ST_OPEN)) {
447		CPC_TTY_DBG("%s: TTY is not opened\n", cpc_tty->name);
448		return -ENODEV;
449	}
450
451	if (count > CPC_TTY_MAX_MTU) {
452		CPC_TTY_DBG("%s: count is invalid\n",cpc_tty->name);
453		return -EINVAL;        /* frame too big */
454	}
455
456	CPC_TTY_DBG("%s: cpc_tty_write data len=%i\n",cpc_tty->name,count);
457
458	pc300chan = (pc300ch_t *)((pc300dev_t*)cpc_tty->pc300dev)->chan;
459	stats = &cpc_tty->pc300dev->dev->stats;
460	card = (pc300_t *) pc300chan->card;
461	ch = pc300chan->channel;
462
463	/* verify DCD signal*/
464	if (cpc_readb(card->hw.scabase + M_REG(ST3,ch)) & ST3_DCD) {
465		/* DCD is OFF */
466		CPC_TTY_DBG("%s : DCD is OFF\n", cpc_tty->name);
467		stats->tx_errors++;
468		stats->tx_carrier_errors++;
469		CPC_TTY_LOCK(card, flags);
470		cpc_writeb(card->hw.scabase + M_REG(CMD, ch), CMD_TX_BUF_CLR);
471
472		if (card->hw.type == PC300_TE) {
473			cpc_writeb(card->hw.falcbase + card->hw.cpld_reg2,
474				cpc_readb(card->hw.falcbase + card->hw.cpld_reg2) &
475				~(CPLD_REG2_FALC_LED1 << (2 *ch)));
476		}
477
478		CPC_TTY_UNLOCK(card, flags);
479
480		return -EINVAL;
481	}
482
483	if (cpc_tty_send_to_card(cpc_tty->pc300dev, (void*)buf, count)) {
484	   /* failed to send */
485	   CPC_TTY_DBG("%s: trasmition error\n", cpc_tty->name);
486	   return 0;
487	}
488	return count;
489}
490
491/*
492 * PC300 TTY Write Room routine
493 *
494 * This routine returns the numbers of characteres the tty driver will accept
495 * for queuing to be written.
496 * o return MTU
497 */
498static int cpc_tty_write_room(struct tty_struct *tty)
499{
500	st_cpc_tty_area    *cpc_tty;
501
502	if (!tty || !tty->driver_data ) {
503		CPC_TTY_DBG("hdlcX-tty: no TTY to write room\n");
504		return -ENODEV;
505	}
506
507	cpc_tty = (st_cpc_tty_area *) tty->driver_data;
508
509	if ((cpc_tty->tty != tty) ||  (cpc_tty->state != CPC_TTY_ST_OPEN)) {
510		CPC_TTY_DBG("%s: TTY is not opened\n",cpc_tty->name);
511		return -ENODEV;
512	}
513
514	CPC_TTY_DBG("%s: write room\n",cpc_tty->name);
515
516	return CPC_TTY_MAX_MTU;
517}
518
519/*
520 * PC300 TTY chars in buffer routine
521 *
522 * This routine returns the chars number in the transmission buffer
523 * o returns 0
524 */
525static int cpc_tty_chars_in_buffer(struct tty_struct *tty)
526{
527	st_cpc_tty_area    *cpc_tty;
528
529	if (!tty || !tty->driver_data ) {
530		CPC_TTY_DBG("hdlcX-tty: no TTY to chars in buffer\n");
531		return -ENODEV;
532	}
533
534	cpc_tty = (st_cpc_tty_area *) tty->driver_data;
535
536	if ((cpc_tty->tty != tty) || (cpc_tty->state != CPC_TTY_ST_OPEN)) {
537		CPC_TTY_DBG("%s: TTY is not opened\n",cpc_tty->name);
538		return -ENODEV;
539	}
540
541	return 0;
542}
543
544static int pc300_tiocmset(struct tty_struct *tty,
545			  unsigned int set, unsigned int clear)
546{
547	st_cpc_tty_area    *cpc_tty;
548
549	CPC_TTY_DBG("%s: set:%x clear:%x\n", __func__, set, clear);
550
551	if (!tty || !tty->driver_data ) {
552	   	CPC_TTY_DBG("hdlcX-tty: no TTY to chars in buffer\n");
553		return -ENODEV;
554	}
555
556	cpc_tty = (st_cpc_tty_area *) tty->driver_data;
557
558	if (set & TIOCM_RTS)
559		cpc_tty_signal_on(cpc_tty->pc300dev, CTL_RTS);
560	if (set & TIOCM_DTR)
561		cpc_tty_signal_on(cpc_tty->pc300dev, CTL_DTR);
562
563	if (clear & TIOCM_RTS)
564		cpc_tty_signal_off(cpc_tty->pc300dev, CTL_RTS);
565	if (clear & TIOCM_DTR)
566		cpc_tty_signal_off(cpc_tty->pc300dev, CTL_DTR);
567
568	return 0;
569}
570
571static int pc300_tiocmget(struct tty_struct *tty)
572{
573	unsigned int result;
574	unsigned char status;
575	unsigned long flags;
576	st_cpc_tty_area  *cpc_tty = (st_cpc_tty_area *) tty->driver_data;
577	pc300dev_t *pc300dev = cpc_tty->pc300dev;
578	pc300ch_t *pc300chan = (pc300ch_t *)pc300dev->chan;
579	pc300_t *card = (pc300_t *) pc300chan->card;
580	int ch = pc300chan->channel;
581
582	cpc_tty = (st_cpc_tty_area *) tty->driver_data;
583
584	CPC_TTY_DBG("%s-tty: tiocmget\n",
585		((struct net_device*)(pc300dev->hdlc))->name);
586
587	CPC_TTY_LOCK(card, flags);
588	status = cpc_readb(card->hw.scabase+M_REG(CTL,ch));
589	CPC_TTY_UNLOCK(card,flags);
590
591	result = ((status & CTL_DTR) ? TIOCM_DTR : 0) |
592		 ((status & CTL_RTS) ? TIOCM_RTS : 0);
593
594	return result;
595}
596
597/*
598 * PC300 TTY Flush Buffer routine
599 *
600 * This routine resets the transmission buffer
601 */
602static void cpc_tty_flush_buffer(struct tty_struct *tty)
603{
604	st_cpc_tty_area    *cpc_tty;
605
606	if (!tty || !tty->driver_data ) {
607	   	CPC_TTY_DBG("hdlcX-tty: no TTY to flush buffer\n");
608		return;
609	}
610
611	cpc_tty = (st_cpc_tty_area *) tty->driver_data;
612
613	if ((cpc_tty->tty != tty) ||  (cpc_tty->state != CPC_TTY_ST_OPEN)) {
614		CPC_TTY_DBG("%s: TTY is not opened\n",cpc_tty->name);
615		return;
616	}
617
618	CPC_TTY_DBG("%s: call wake_up_interruptible\n",cpc_tty->name);
619
620	tty_wakeup(tty);
621	return;
622}
623
624/*
625 * PC300 TTY Hangup routine
626 *
627 * This routine is called by the tty driver to hangup the interface
628 * o clear DTR signal
629 */
630
631static void cpc_tty_hangup(struct tty_struct *tty)
632{
633	st_cpc_tty_area    *cpc_tty;
634	int res;
635
636	if (!tty || !tty->driver_data ) {
637		CPC_TTY_DBG("hdlcX-tty: no TTY to hangup\n");
638		return ;
639	}
640
641	cpc_tty = (st_cpc_tty_area *) tty->driver_data;
642
643	if ((cpc_tty->tty != tty) || (cpc_tty->state != CPC_TTY_ST_OPEN)) {
644		CPC_TTY_DBG("%s: TTY is not opened\n",cpc_tty->name);
645		return ;
646	}
647	if (!serial_drv.refcount && cpc_tty_unreg_flag) {
648		cpc_tty_unreg_flag = 0;
649		CPC_TTY_DBG("%s: unregister the tty driver\n", cpc_tty->name);
650		if ((res=tty_unregister_driver(&serial_drv))) {
651			CPC_TTY_DBG("%s: ERROR ->unregister the tty driver error=%d\n",
652							cpc_tty->name,res);
653		}
654	}
655	cpc_tty_signal_off(cpc_tty->pc300dev, CTL_DTR);
656}
657
658/*
659 * PC300 TTY RX work routine
660 * This routine treats RX work
661 * o verify read buffer
662 * o call the line disc. read
663 * o free memory
664 */
665static void cpc_tty_rx_work(struct work_struct *work)
666{
667	st_cpc_tty_area *cpc_tty;
668	unsigned long port;
669	int i, j;
670	volatile st_cpc_rx_buf *buf;
671	char flags=0,flg_rx=1;
672	struct tty_ldisc *ld;
673
674	if (cpc_tty_cnt == 0) return;
675
676	for (i=0; (i < 4) && flg_rx ; i++) {
677		flg_rx = 0;
678
679		cpc_tty = container_of(work, st_cpc_tty_area, tty_rx_work);
680		port = cpc_tty - cpc_tty_area;
681
682		for (j=0; j < CPC_TTY_NPORTS; j++) {
683			cpc_tty = &cpc_tty_area[port];
684
685			if ((buf=cpc_tty->buf_rx.first) != NULL) {
686				if (cpc_tty->tty) {
687					ld = tty_ldisc_ref(cpc_tty->tty);
688					if (ld) {
689						if (ld->ops->receive_buf) {
690							CPC_TTY_DBG("%s: call line disc. receive_buf\n",cpc_tty->name);
691							ld->ops->receive_buf(cpc_tty->tty, (char *)(buf->data), &flags, buf->size);
692						}
693						tty_ldisc_deref(ld);
694					}
695				}
696				cpc_tty->buf_rx.first = cpc_tty->buf_rx.first->next;
697				kfree((void *)buf);
698				buf = cpc_tty->buf_rx.first;
699				flg_rx = 1;
700			}
701			if (++port == CPC_TTY_NPORTS) port = 0;
702		}
703	}
704}
705
706/*
707 * PC300 TTY RX work routine
708 *
709 * This routine treats RX interrupt.
710 * o read all frames in card
711 * o verify the frame size
712 * o read the frame in rx buffer
713 */
714static void cpc_tty_rx_disc_frame(pc300ch_t *pc300chan)
715{
716	volatile pcsca_bd_t __iomem * ptdescr;
717	volatile unsigned char status;
718	pc300_t *card = (pc300_t *)pc300chan->card;
719	int ch = pc300chan->channel;
720
721	/* dma buf read */
722	ptdescr = (pcsca_bd_t __iomem *)(card->hw.rambase +
723				RX_BD_ADDR(ch, pc300chan->rx_first_bd));
724	while (pc300chan->rx_first_bd != pc300chan->rx_last_bd) {
725		status = cpc_readb(&ptdescr->status);
726		cpc_writeb(&ptdescr->status, 0);
727		cpc_writeb(&ptdescr->len, 0);
728		pc300chan->rx_first_bd = (pc300chan->rx_first_bd + 1) &
729					(N_DMA_RX_BUF - 1);
730		if (status & DST_EOM) {
731			break; /* end of message */
732		}
733		ptdescr = (pcsca_bd_t __iomem *)(card->hw.rambase + cpc_readl(&ptdescr->next));
734	}
735}
736
737void cpc_tty_receive(pc300dev_t *pc300dev)
738{
739	st_cpc_tty_area *cpc_tty;
740	pc300ch_t *pc300chan = (pc300ch_t *)pc300dev->chan;
741	pc300_t *card = (pc300_t *)pc300chan->card;
742	int ch = pc300chan->channel;
743	volatile pcsca_bd_t  __iomem * ptdescr;
744	struct net_device_stats *stats = &pc300dev->dev->stats;
745	int rx_len, rx_aux;
746	volatile unsigned char status;
747	unsigned short first_bd = pc300chan->rx_first_bd;
748	st_cpc_rx_buf *new = NULL;
749	unsigned char dsr_rx;
750
751	if (pc300dev->cpc_tty == NULL) {
752		return;
753	}
754
755	dsr_rx = cpc_readb(card->hw.scabase + DSR_RX(ch));
756
757	cpc_tty = pc300dev->cpc_tty;
758
759	while (1) {
760		rx_len = 0;
761		ptdescr = (pcsca_bd_t  __iomem *)(card->hw.rambase + RX_BD_ADDR(ch, first_bd));
762		while ((status = cpc_readb(&ptdescr->status)) & DST_OSB) {
763			rx_len += cpc_readw(&ptdescr->len);
764			first_bd = (first_bd + 1) & (N_DMA_RX_BUF - 1);
765			if (status & DST_EOM) {
766				break;
767			}
768			ptdescr = (pcsca_bd_t __iomem *)(card->hw.rambase+cpc_readl(&ptdescr->next));
769		}
770
771		if (!rx_len) {
772			if (dsr_rx & DSR_BOF) {
773				/* update EDA */
774				cpc_writel(card->hw.scabase + DRX_REG(EDAL, ch),
775						RX_BD_ADDR(ch, pc300chan->rx_last_bd));
776			}
777			kfree(new);
778			return;
779		}
780
781		if (rx_len > CPC_TTY_MAX_MTU) {
782			/* Free RX descriptors */
783			CPC_TTY_DBG("%s: frame size is invalid.\n",cpc_tty->name);
784			stats->rx_errors++;
785			stats->rx_frame_errors++;
786			cpc_tty_rx_disc_frame(pc300chan);
787			continue;
788		}
789
790		new = kmalloc(rx_len + sizeof(st_cpc_rx_buf), GFP_ATOMIC);
791		if (!new) {
792			cpc_tty_rx_disc_frame(pc300chan);
793			continue;
794		}
795
796		/* dma buf read */
797		ptdescr = (pcsca_bd_t __iomem *)(card->hw.rambase +
798				RX_BD_ADDR(ch, pc300chan->rx_first_bd));
799
800		rx_len = 0;	/* counter frame size */
801
802		while ((status = cpc_readb(&ptdescr->status)) & DST_OSB) {
803			rx_aux = cpc_readw(&ptdescr->len);
804			if ((status & (DST_OVR | DST_CRC | DST_RBIT |  DST_SHRT | DST_ABT))
805				|| (rx_aux > BD_DEF_LEN)) {
806				CPC_TTY_DBG("%s: reception error\n", cpc_tty->name);
807				stats->rx_errors++;
808				if (status & DST_OVR) {
809					stats->rx_fifo_errors++;
810				}
811				if (status & DST_CRC) {
812					stats->rx_crc_errors++;
813				}
814				if ((status & (DST_RBIT | DST_SHRT | DST_ABT)) ||
815					(rx_aux > BD_DEF_LEN))	{
816					stats->rx_frame_errors++;
817				}
818				/* discard remainig descriptors used by the bad frame */
819				CPC_TTY_DBG("%s: reception error - discard descriptors",
820						cpc_tty->name);
821				cpc_tty_rx_disc_frame(pc300chan);
822				rx_len = 0;
823				kfree(new);
824				new = NULL;
825				break; /* read next frame - while(1) */
826			}
827
828			if (cpc_tty->state != CPC_TTY_ST_OPEN) {
829				/* Free RX descriptors */
830				cpc_tty_rx_disc_frame(pc300chan);
831				stats->rx_dropped++;
832				rx_len = 0;
833				kfree(new);
834				new = NULL;
835				break; /* read next frame - while(1) */
836			}
837
838			/* read the segment of the frame */
839			if (rx_aux != 0) {
840				memcpy_fromio((new->data + rx_len),
841					(void __iomem *)(card->hw.rambase +
842					 cpc_readl(&ptdescr->ptbuf)), rx_aux);
843				rx_len += rx_aux;
844			}
845			cpc_writeb(&ptdescr->status,0);
846			cpc_writeb(&ptdescr->len, 0);
847			pc300chan->rx_first_bd = (pc300chan->rx_first_bd + 1) &
848					(N_DMA_RX_BUF -1);
849			if (status & DST_EOM)break;
850
851			ptdescr = (pcsca_bd_t __iomem *) (card->hw.rambase +
852					cpc_readl(&ptdescr->next));
853		}
854		/* update pointer */
855		pc300chan->rx_last_bd = (pc300chan->rx_first_bd - 1) &
856					(N_DMA_RX_BUF - 1) ;
857		if (!(dsr_rx & DSR_BOF)) {
858			/* update EDA */
859			cpc_writel(card->hw.scabase + DRX_REG(EDAL, ch),
860					RX_BD_ADDR(ch, pc300chan->rx_last_bd));
861		}
862		if (rx_len != 0) {
863			stats->rx_bytes += rx_len;
864
865			if (pc300dev->trace_on) {
866				cpc_tty_trace(pc300dev, new->data,rx_len, 'R');
867			}
868			new->size = rx_len;
869			new->next = NULL;
870			if (cpc_tty->buf_rx.first == NULL) {
871				cpc_tty->buf_rx.first = new;
872				cpc_tty->buf_rx.last = new;
873			} else {
874				cpc_tty->buf_rx.last->next = new;
875				cpc_tty->buf_rx.last = new;
876			}
877			schedule_work(&(cpc_tty->tty_rx_work));
878			stats->rx_packets++;
879		}
880	}
881}
882
883/*
884 * PC300 TTY TX work routine
885 *
886 * This routine treats TX interrupt.
887 * o if need call line discipline wakeup
888 * o call wake_up_interruptible
889 */
890static void cpc_tty_tx_work(struct work_struct *work)
891{
892	st_cpc_tty_area *cpc_tty =
893		container_of(work, st_cpc_tty_area, tty_tx_work);
894	struct tty_struct *tty;
895
896	CPC_TTY_DBG("%s: cpc_tty_tx_work init\n",cpc_tty->name);
897
898	if ((tty = cpc_tty->tty) == NULL) {
899		CPC_TTY_DBG("%s: the interface is not opened\n",cpc_tty->name);
900		return;
901	}
902	tty_wakeup(tty);
903}
904
905/*
906 * PC300 TTY send to card routine
907 *
908 * This routine send data to card.
909 * o clear descriptors
910 * o write data to DMA buffers
911 * o start the transmission
912 */
913static int cpc_tty_send_to_card(pc300dev_t *dev,void* buf, int len)
914{
915	pc300ch_t *chan = (pc300ch_t *)dev->chan;
916	pc300_t *card = (pc300_t *)chan->card;
917	int ch = chan->channel;
918	struct net_device_stats *stats = &dev->dev->stats;
919	unsigned long flags;
920	volatile pcsca_bd_t __iomem *ptdescr;
921	int i, nchar;
922	int tosend = len;
923	int nbuf = ((len - 1)/BD_DEF_LEN) + 1;
924	unsigned char *pdata=buf;
925
926	CPC_TTY_DBG("%s:cpc_tty_send_to_cars len=%i",
927			(st_cpc_tty_area *)dev->cpc_tty->name,len);
928
929	if (nbuf >= card->chan[ch].nfree_tx_bd) {
930		return 1;
931	}
932
933	/* write buffer to DMA buffers */
934	CPC_TTY_DBG("%s: call dma_buf_write\n",
935			(st_cpc_tty_area *)dev->cpc_tty->name);
936	for (i = 0 ; i < nbuf ; i++) {
937		ptdescr = (pcsca_bd_t __iomem *)(card->hw.rambase +
938			TX_BD_ADDR(ch, card->chan[ch].tx_next_bd));
939		nchar = (BD_DEF_LEN > tosend) ? tosend : BD_DEF_LEN;
940		if (cpc_readb(&ptdescr->status) & DST_OSB) {
941			memcpy_toio((void __iomem *)(card->hw.rambase +
942				cpc_readl(&ptdescr->ptbuf)),
943				&pdata[len - tosend],
944				nchar);
945			card->chan[ch].nfree_tx_bd--;
946			if ((i + 1) == nbuf) {
947				/* This must be the last BD to be used */
948				cpc_writeb(&ptdescr->status, DST_EOM);
949			} else {
950				cpc_writeb(&ptdescr->status, 0);
951			}
952			cpc_writew(&ptdescr->len, nchar);
953		} else {
954			CPC_TTY_DBG("%s: error in dma_buf_write\n",
955					(st_cpc_tty_area *)dev->cpc_tty->name);
956			stats->tx_dropped++;
957			return 1;
958		}
959		tosend -= nchar;
960		card->chan[ch].tx_next_bd =
961			(card->chan[ch].tx_next_bd + 1) & (N_DMA_TX_BUF - 1);
962	}
963
964	if (dev->trace_on) {
965		cpc_tty_trace(dev, buf, len,'T');
966	}
967
968	/* start transmission */
969	CPC_TTY_DBG("%s: start transmission\n",
970		(st_cpc_tty_area *)dev->cpc_tty->name);
971
972	CPC_TTY_LOCK(card, flags);
973	cpc_writeb(card->hw.scabase + DTX_REG(EDAL, ch),
974			TX_BD_ADDR(ch, chan->tx_next_bd));
975	cpc_writeb(card->hw.scabase + M_REG(CMD, ch), CMD_TX_ENA);
976	cpc_writeb(card->hw.scabase + DSR_TX(ch), DSR_DE);
977
978	if (card->hw.type == PC300_TE) {
979		cpc_writeb(card->hw.falcbase + card->hw.cpld_reg2,
980			cpc_readb(card->hw.falcbase + card->hw.cpld_reg2) |
981			(CPLD_REG2_FALC_LED1 << (2 * ch)));
982	}
983	CPC_TTY_UNLOCK(card, flags);
984	return 0;
985}
986
987/*
988 *	PC300 TTY trace routine
989 *
990 *  This routine send trace of connection to application.
991 *  o clear descriptors
992 *  o write data to DMA buffers
993 *  o start the transmission
994 */
995
996static void cpc_tty_trace(pc300dev_t *dev, char* buf, int len, char rxtx)
997{
998	struct sk_buff *skb;
999
1000	if ((skb = dev_alloc_skb(10 + len)) == NULL) {
1001		/* out of memory */
1002		CPC_TTY_DBG("%s: tty_trace - out of memory\n", dev->dev->name);
1003		return;
1004	}
1005
1006	skb_put (skb, 10 + len);
1007	skb->dev = dev->dev;
1008	skb->protocol = htons(ETH_P_CUST);
1009	skb_reset_mac_header(skb);
1010	skb->pkt_type = PACKET_HOST;
1011	skb->len = 10 + len;
1012
1013	skb_copy_to_linear_data(skb, dev->dev->name, 5);
1014	skb->data[5] = '[';
1015	skb->data[6] = rxtx;
1016	skb->data[7] = ']';
1017	skb->data[8] = ':';
1018	skb->data[9] = ' ';
1019	skb_copy_to_linear_data_offset(skb, 10, buf, len);
1020	netif_rx(skb);
1021}
1022
1023/*
1024 *	PC300 TTY unregister service routine
1025 *
1026 *	This routine unregister one interface.
1027 */
1028void cpc_tty_unregister_service(pc300dev_t *pc300dev)
1029{
1030	st_cpc_tty_area *cpc_tty;
1031	ulong flags;
1032	int res;
1033
1034	if ((cpc_tty= (st_cpc_tty_area *) pc300dev->cpc_tty) == NULL) {
1035		CPC_TTY_DBG("%s: interface is not TTY\n", pc300dev->dev->name);
1036		return;
1037	}
1038	CPC_TTY_DBG("%s: cpc_tty_unregister_service", cpc_tty->name);
1039
1040	if (cpc_tty->pc300dev != pc300dev) {
1041		CPC_TTY_DBG("%s: invalid tty ptr=%s\n",
1042		pc300dev->dev->name, cpc_tty->name);
1043		return;
1044	}
1045
1046	if (--cpc_tty_cnt == 0) {
1047		if (serial_drv.refcount) {
1048			CPC_TTY_DBG("%s: unregister is not possible, refcount=%d",
1049							cpc_tty->name, serial_drv.refcount);
1050			cpc_tty_cnt++;
1051			cpc_tty_unreg_flag = 1;
1052			return;
1053		} else {
1054			CPC_TTY_DBG("%s: unregister the tty driver\n", cpc_tty->name);
1055			if ((res=tty_unregister_driver(&serial_drv))) {
1056				CPC_TTY_DBG("%s: ERROR ->unregister the tty driver error=%d\n",
1057								cpc_tty->name,res);
1058			}
1059		}
1060	}
1061	CPC_TTY_LOCK(pc300dev->chan->card,flags);
1062	cpc_tty->tty = NULL;
1063	CPC_TTY_UNLOCK(pc300dev->chan->card, flags);
1064	cpc_tty->tty_minor = 0;
1065	cpc_tty->state = CPC_TTY_ST_IDLE;
1066}
1067
1068/*
1069 * PC300 TTY trigger poll routine
1070 * This routine is called by pc300driver to treats Tx interrupt.
1071 */
1072void cpc_tty_trigger_poll(pc300dev_t *pc300dev)
1073{
1074	st_cpc_tty_area *cpc_tty = (st_cpc_tty_area *)pc300dev->cpc_tty;
1075	if (!cpc_tty) {
1076		return;
1077	}
1078	schedule_work(&(cpc_tty->tty_tx_work));
1079}
1080