xref: /linux/drivers/ipack/devices/ipoctal.c (revision d0b73b488c55df905ea8faaad079f8535629ed26)
1 /**
2  * ipoctal.c
3  *
4  * driver for the GE IP-OCTAL boards
5  *
6  * Copyright (C) 2009-2012 CERN (www.cern.ch)
7  * Author: Nicolas Serafini, EIC2 SA
8  * Author: Samuel Iglesias Gonsalvez <siglesias@igalia.com>
9  *
10  * This program is free software; you can redistribute it and/or modify it
11  * under the terms of the GNU General Public License as published by the Free
12  * Software Foundation; version 2 of the License.
13  */
14 
15 #include <linux/device.h>
16 #include <linux/module.h>
17 #include <linux/interrupt.h>
18 #include <linux/sched.h>
19 #include <linux/tty.h>
20 #include <linux/serial.h>
21 #include <linux/tty_flip.h>
22 #include <linux/slab.h>
23 #include <linux/atomic.h>
24 #include <linux/io.h>
25 #include <linux/ipack.h>
26 #include "ipoctal.h"
27 #include "scc2698.h"
28 
29 #define IP_OCTAL_ID_SPACE_VECTOR    0x41
30 #define IP_OCTAL_NB_BLOCKS          4
31 
32 static const struct tty_operations ipoctal_fops;
33 
34 struct ipoctal_channel {
35 	struct ipoctal_stats		stats;
36 	unsigned int			nb_bytes;
37 	wait_queue_head_t		queue;
38 	spinlock_t			lock;
39 	unsigned int			pointer_read;
40 	unsigned int			pointer_write;
41 	atomic_t			open;
42 	struct tty_port			tty_port;
43 	union scc2698_channel __iomem	*regs;
44 	union scc2698_block __iomem	*block_regs;
45 	unsigned int			board_id;
46 	unsigned char			*board_write;
47 	u8				isr_rx_rdy_mask;
48 	u8				isr_tx_rdy_mask;
49 };
50 
51 struct ipoctal {
52 	struct ipack_device		*dev;
53 	unsigned int			board_id;
54 	struct ipoctal_channel		channel[NR_CHANNELS];
55 	unsigned char			write;
56 	struct tty_driver		*tty_drv;
57 	u8 __iomem			*mem8_space;
58 	u8 __iomem			*int_space;
59 };
60 
61 static int ipoctal_port_activate(struct tty_port *port, struct tty_struct *tty)
62 {
63 	struct ipoctal_channel *channel;
64 
65 	channel = dev_get_drvdata(tty->dev);
66 
67 	iowrite8(CR_ENABLE_RX, &channel->regs->w.cr);
68 	return 0;
69 }
70 
71 static int ipoctal_open(struct tty_struct *tty, struct file *file)
72 {
73 	int res;
74 	struct ipoctal_channel *channel;
75 
76 	channel = dev_get_drvdata(tty->dev);
77 
78 	if (atomic_read(&channel->open))
79 		return -EBUSY;
80 
81 	tty->driver_data = channel;
82 
83 	res = tty_port_open(&channel->tty_port, tty, file);
84 	if (res)
85 		return res;
86 
87 	atomic_inc(&channel->open);
88 	return 0;
89 }
90 
91 static void ipoctal_reset_stats(struct ipoctal_stats *stats)
92 {
93 	stats->tx = 0;
94 	stats->rx = 0;
95 	stats->rcv_break = 0;
96 	stats->framing_err = 0;
97 	stats->overrun_err = 0;
98 	stats->parity_err = 0;
99 }
100 
101 static void ipoctal_free_channel(struct ipoctal_channel *channel)
102 {
103 	ipoctal_reset_stats(&channel->stats);
104 	channel->pointer_read = 0;
105 	channel->pointer_write = 0;
106 	channel->nb_bytes = 0;
107 }
108 
109 static void ipoctal_close(struct tty_struct *tty, struct file *filp)
110 {
111 	struct ipoctal_channel *channel = tty->driver_data;
112 
113 	tty_port_close(&channel->tty_port, tty, filp);
114 
115 	if (atomic_dec_and_test(&channel->open))
116 		ipoctal_free_channel(channel);
117 }
118 
119 static int ipoctal_get_icount(struct tty_struct *tty,
120 			      struct serial_icounter_struct *icount)
121 {
122 	struct ipoctal_channel *channel = tty->driver_data;
123 
124 	icount->cts = 0;
125 	icount->dsr = 0;
126 	icount->rng = 0;
127 	icount->dcd = 0;
128 	icount->rx = channel->stats.rx;
129 	icount->tx = channel->stats.tx;
130 	icount->frame = channel->stats.framing_err;
131 	icount->parity = channel->stats.parity_err;
132 	icount->brk = channel->stats.rcv_break;
133 	return 0;
134 }
135 
136 static void ipoctal_irq_rx(struct ipoctal_channel *channel,
137 			   struct tty_struct *tty, u8 sr)
138 {
139 	unsigned char value;
140 	unsigned char flag = TTY_NORMAL;
141 	u8 isr;
142 
143 	do {
144 		value = ioread8(&channel->regs->r.rhr);
145 		/* Error: count statistics */
146 		if (sr & SR_ERROR) {
147 			iowrite8(CR_CMD_RESET_ERR_STATUS, &channel->regs->w.cr);
148 
149 			if (sr & SR_OVERRUN_ERROR) {
150 				channel->stats.overrun_err++;
151 				/* Overrun doesn't affect the current character*/
152 				tty_insert_flip_char(tty, 0, TTY_OVERRUN);
153 			}
154 			if (sr & SR_PARITY_ERROR) {
155 				channel->stats.parity_err++;
156 				flag = TTY_PARITY;
157 			}
158 			if (sr & SR_FRAMING_ERROR) {
159 				channel->stats.framing_err++;
160 				flag = TTY_FRAME;
161 			}
162 			if (sr & SR_RECEIVED_BREAK) {
163 				iowrite8(CR_CMD_RESET_BREAK_CHANGE, &channel->regs->w.cr);
164 				channel->stats.rcv_break++;
165 				flag = TTY_BREAK;
166 			}
167 		}
168 		tty_insert_flip_char(tty, value, flag);
169 
170 		/* Check if there are more characters in RX FIFO
171 		 * If there are more, the isr register for this channel
172 		 * has enabled the RxRDY|FFULL bit.
173 		 */
174 		isr = ioread8(&channel->block_regs->r.isr);
175 		sr = ioread8(&channel->regs->r.sr);
176 	} while (isr & channel->isr_rx_rdy_mask);
177 
178 	tty_flip_buffer_push(tty);
179 }
180 
181 static void ipoctal_irq_tx(struct ipoctal_channel *channel)
182 {
183 	unsigned char value;
184 	unsigned int *pointer_write = &channel->pointer_write;
185 
186 	if (channel->nb_bytes <= 0) {
187 		channel->nb_bytes = 0;
188 		return;
189 	}
190 
191 	value = channel->tty_port.xmit_buf[*pointer_write];
192 	iowrite8(value, &channel->regs->w.thr);
193 	channel->stats.tx++;
194 	(*pointer_write)++;
195 	*pointer_write = *pointer_write % PAGE_SIZE;
196 	channel->nb_bytes--;
197 
198 	if ((channel->nb_bytes == 0) &&
199 	    (waitqueue_active(&channel->queue))) {
200 
201 		if (channel->board_id != IPACK1_DEVICE_ID_SBS_OCTAL_485) {
202 			*channel->board_write = 1;
203 			wake_up_interruptible(&channel->queue);
204 		}
205 	}
206 }
207 
208 static void ipoctal_irq_channel(struct ipoctal_channel *channel)
209 {
210 	u8 isr, sr;
211 	struct tty_struct *tty;
212 
213 	/* If there is no client, skip the check */
214 	if (!atomic_read(&channel->open))
215 		return;
216 
217 	tty = tty_port_tty_get(&channel->tty_port);
218 	if (!tty)
219 		return;
220 	/* The HW is organized in pair of channels.  See which register we need
221 	 * to read from */
222 	isr = ioread8(&channel->block_regs->r.isr);
223 	sr = ioread8(&channel->regs->r.sr);
224 
225 	/* In case of RS-485, change from TX to RX when finishing TX.
226 	 * Half-duplex. */
227 	if ((channel->board_id == IPACK1_DEVICE_ID_SBS_OCTAL_485) &&
228 	    (sr & SR_TX_EMPTY) && (channel->nb_bytes == 0)) {
229 		iowrite8(CR_DISABLE_TX, &channel->regs->w.cr);
230 		iowrite8(CR_CMD_NEGATE_RTSN, &channel->regs->w.cr);
231 		iowrite8(CR_ENABLE_RX, &channel->regs->w.cr);
232 		*channel->board_write = 1;
233 		wake_up_interruptible(&channel->queue);
234 	}
235 
236 	/* RX data */
237 	if ((isr & channel->isr_rx_rdy_mask) && (sr & SR_RX_READY))
238 		ipoctal_irq_rx(channel, tty, sr);
239 
240 	/* TX of each character */
241 	if ((isr & channel->isr_tx_rdy_mask) && (sr & SR_TX_READY))
242 		ipoctal_irq_tx(channel);
243 
244 	tty_flip_buffer_push(tty);
245 	tty_kref_put(tty);
246 }
247 
248 static irqreturn_t ipoctal_irq_handler(void *arg)
249 {
250 	unsigned int i;
251 	struct ipoctal *ipoctal = (struct ipoctal *) arg;
252 
253 	/* Check all channels */
254 	for (i = 0; i < NR_CHANNELS; i++)
255 		ipoctal_irq_channel(&ipoctal->channel[i]);
256 
257 	/* Clear the IPack device interrupt */
258 	readw(ipoctal->int_space + ACK_INT_REQ0);
259 	readw(ipoctal->int_space + ACK_INT_REQ1);
260 
261 	return IRQ_HANDLED;
262 }
263 
264 static const struct tty_port_operations ipoctal_tty_port_ops = {
265 	.dtr_rts = NULL,
266 	.activate = ipoctal_port_activate,
267 };
268 
269 static int ipoctal_inst_slot(struct ipoctal *ipoctal, unsigned int bus_nr,
270 			     unsigned int slot)
271 {
272 	int res;
273 	int i;
274 	struct tty_driver *tty;
275 	char name[20];
276 	struct ipoctal_channel *channel;
277 	struct ipack_region *region;
278 	void __iomem *addr;
279 	union scc2698_channel __iomem *chan_regs;
280 	union scc2698_block __iomem *block_regs;
281 
282 	ipoctal->board_id = ipoctal->dev->id_device;
283 
284 	region = &ipoctal->dev->region[IPACK_IO_SPACE];
285 	addr = devm_ioremap_nocache(&ipoctal->dev->dev,
286 				    region->start, region->size);
287 	if (!addr) {
288 		dev_err(&ipoctal->dev->dev,
289 			"Unable to map slot [%d:%d] IO space!\n",
290 			bus_nr, slot);
291 		return -EADDRNOTAVAIL;
292 	}
293 	/* Save the virtual address to access the registers easily */
294 	chan_regs =
295 		(union scc2698_channel __iomem *) addr;
296 	block_regs =
297 		(union scc2698_block __iomem *) addr;
298 
299 	region = &ipoctal->dev->region[IPACK_INT_SPACE];
300 	ipoctal->int_space =
301 		devm_ioremap_nocache(&ipoctal->dev->dev,
302 				     region->start, region->size);
303 	if (!ipoctal->int_space) {
304 		dev_err(&ipoctal->dev->dev,
305 			"Unable to map slot [%d:%d] INT space!\n",
306 			bus_nr, slot);
307 		return -EADDRNOTAVAIL;
308 	}
309 
310 	region = &ipoctal->dev->region[IPACK_MEM8_SPACE];
311 	ipoctal->mem8_space =
312 		devm_ioremap_nocache(&ipoctal->dev->dev,
313 				     region->start, 0x8000);
314 	if (!addr) {
315 		dev_err(&ipoctal->dev->dev,
316 			"Unable to map slot [%d:%d] MEM8 space!\n",
317 			bus_nr, slot);
318 		return -EADDRNOTAVAIL;
319 	}
320 
321 
322 	/* Disable RX and TX before touching anything */
323 	for (i = 0; i < NR_CHANNELS ; i++) {
324 		struct ipoctal_channel *channel = &ipoctal->channel[i];
325 		channel->regs = chan_regs + i;
326 		channel->block_regs = block_regs + (i >> 1);
327 		channel->board_write = &ipoctal->write;
328 		channel->board_id = ipoctal->board_id;
329 		if (i & 1) {
330 			channel->isr_tx_rdy_mask = ISR_TxRDY_B;
331 			channel->isr_rx_rdy_mask = ISR_RxRDY_FFULL_B;
332 		} else {
333 			channel->isr_tx_rdy_mask = ISR_TxRDY_A;
334 			channel->isr_rx_rdy_mask = ISR_RxRDY_FFULL_A;
335 		}
336 
337 		iowrite8(CR_DISABLE_RX | CR_DISABLE_TX, &channel->regs->w.cr);
338 		iowrite8(CR_CMD_RESET_RX, &channel->regs->w.cr);
339 		iowrite8(CR_CMD_RESET_TX, &channel->regs->w.cr);
340 		iowrite8(MR1_CHRL_8_BITS | MR1_ERROR_CHAR | MR1_RxINT_RxRDY,
341 			 &channel->regs->w.mr); /* mr1 */
342 		iowrite8(0, &channel->regs->w.mr); /* mr2 */
343 		iowrite8(TX_CLK_9600  | RX_CLK_9600, &channel->regs->w.csr);
344 	}
345 
346 	for (i = 0; i < IP_OCTAL_NB_BLOCKS; i++) {
347 		iowrite8(ACR_BRG_SET2, &block_regs[i].w.acr);
348 		iowrite8(OPCR_MPP_OUTPUT | OPCR_MPOa_RTSN | OPCR_MPOb_RTSN,
349 			 &block_regs[i].w.opcr);
350 		iowrite8(IMR_TxRDY_A | IMR_RxRDY_FFULL_A | IMR_DELTA_BREAK_A |
351 			 IMR_TxRDY_B | IMR_RxRDY_FFULL_B | IMR_DELTA_BREAK_B,
352 			 &block_regs[i].w.imr);
353 	}
354 
355 	/*
356 	 * IP-OCTAL has different addresses to copy its IRQ vector.
357 	 * Depending of the carrier these addresses are accesible or not.
358 	 * More info in the datasheet.
359 	 */
360 	ipoctal->dev->bus->ops->request_irq(ipoctal->dev,
361 				       ipoctal_irq_handler, ipoctal);
362 	/* Dummy write */
363 	iowrite8(1, ipoctal->mem8_space + 1);
364 
365 	/* Register the TTY device */
366 
367 	/* Each IP-OCTAL channel is a TTY port */
368 	tty = alloc_tty_driver(NR_CHANNELS);
369 
370 	if (!tty)
371 		return -ENOMEM;
372 
373 	/* Fill struct tty_driver with ipoctal data */
374 	tty->owner = THIS_MODULE;
375 	tty->driver_name = KBUILD_MODNAME;
376 	sprintf(name, KBUILD_MODNAME ".%d.%d.", bus_nr, slot);
377 	tty->name = name;
378 	tty->major = 0;
379 
380 	tty->minor_start = 0;
381 	tty->type = TTY_DRIVER_TYPE_SERIAL;
382 	tty->subtype = SERIAL_TYPE_NORMAL;
383 	tty->flags = TTY_DRIVER_REAL_RAW | TTY_DRIVER_DYNAMIC_DEV;
384 	tty->init_termios = tty_std_termios;
385 	tty->init_termios.c_cflag = B9600 | CS8 | CREAD | HUPCL | CLOCAL;
386 	tty->init_termios.c_ispeed = 9600;
387 	tty->init_termios.c_ospeed = 9600;
388 
389 	tty_set_operations(tty, &ipoctal_fops);
390 	res = tty_register_driver(tty);
391 	if (res) {
392 		dev_err(&ipoctal->dev->dev, "Can't register tty driver.\n");
393 		put_tty_driver(tty);
394 		return res;
395 	}
396 
397 	/* Save struct tty_driver for use it when uninstalling the device */
398 	ipoctal->tty_drv = tty;
399 
400 	for (i = 0; i < NR_CHANNELS; i++) {
401 		struct device *tty_dev;
402 
403 		channel = &ipoctal->channel[i];
404 		tty_port_init(&channel->tty_port);
405 		tty_port_alloc_xmit_buf(&channel->tty_port);
406 		channel->tty_port.ops = &ipoctal_tty_port_ops;
407 
408 		ipoctal_reset_stats(&channel->stats);
409 		channel->nb_bytes = 0;
410 		init_waitqueue_head(&channel->queue);
411 
412 		spin_lock_init(&channel->lock);
413 		channel->pointer_read = 0;
414 		channel->pointer_write = 0;
415 		tty_dev = tty_port_register_device(&channel->tty_port, tty, i, NULL);
416 		if (IS_ERR(tty_dev)) {
417 			dev_err(&ipoctal->dev->dev, "Failed to register tty device.\n");
418 			tty_port_destroy(&channel->tty_port);
419 			continue;
420 		}
421 		dev_set_drvdata(tty_dev, channel);
422 
423 		/*
424 		 * Enable again the RX. TX will be enabled when
425 		 * there is something to send
426 		 */
427 		iowrite8(CR_ENABLE_RX, &channel->regs->w.cr);
428 	}
429 
430 	return 0;
431 }
432 
433 static inline int ipoctal_copy_write_buffer(struct ipoctal_channel *channel,
434 					    const unsigned char *buf,
435 					    int count)
436 {
437 	unsigned long flags;
438 	int i;
439 	unsigned int *pointer_read = &channel->pointer_read;
440 
441 	/* Copy the bytes from the user buffer to the internal one */
442 	for (i = 0; i < count; i++) {
443 		if (i <= (PAGE_SIZE - channel->nb_bytes)) {
444 			spin_lock_irqsave(&channel->lock, flags);
445 			channel->tty_port.xmit_buf[*pointer_read] = buf[i];
446 			*pointer_read = (*pointer_read + 1) % PAGE_SIZE;
447 			channel->nb_bytes++;
448 			spin_unlock_irqrestore(&channel->lock, flags);
449 		} else {
450 			break;
451 		}
452 	}
453 	return i;
454 }
455 
456 static int ipoctal_write_tty(struct tty_struct *tty,
457 			     const unsigned char *buf, int count)
458 {
459 	struct ipoctal_channel *channel = tty->driver_data;
460 	unsigned int char_copied;
461 
462 	char_copied = ipoctal_copy_write_buffer(channel, buf, count);
463 
464 	/* As the IP-OCTAL 485 only supports half duplex, do it manually */
465 	if (channel->board_id == IPACK1_DEVICE_ID_SBS_OCTAL_485) {
466 		iowrite8(CR_DISABLE_RX, &channel->regs->w.cr);
467 		iowrite8(CR_CMD_ASSERT_RTSN, &channel->regs->w.cr);
468 	}
469 
470 	/*
471 	 * Send a packet and then disable TX to avoid failure after several send
472 	 * operations
473 	 */
474 	iowrite8(CR_ENABLE_TX, &channel->regs->w.cr);
475 	wait_event_interruptible(channel->queue, *channel->board_write);
476 	iowrite8(CR_DISABLE_TX, &channel->regs->w.cr);
477 
478 	*channel->board_write = 0;
479 	return char_copied;
480 }
481 
482 static int ipoctal_write_room(struct tty_struct *tty)
483 {
484 	struct ipoctal_channel *channel = tty->driver_data;
485 
486 	return PAGE_SIZE - channel->nb_bytes;
487 }
488 
489 static int ipoctal_chars_in_buffer(struct tty_struct *tty)
490 {
491 	struct ipoctal_channel *channel = tty->driver_data;
492 
493 	return channel->nb_bytes;
494 }
495 
496 static void ipoctal_set_termios(struct tty_struct *tty,
497 				struct ktermios *old_termios)
498 {
499 	unsigned int cflag;
500 	unsigned char mr1 = 0;
501 	unsigned char mr2 = 0;
502 	unsigned char csr = 0;
503 	struct ipoctal_channel *channel = tty->driver_data;
504 	speed_t baud;
505 
506 	cflag = tty->termios.c_cflag;
507 
508 	/* Disable and reset everything before change the setup */
509 	iowrite8(CR_DISABLE_RX | CR_DISABLE_TX, &channel->regs->w.cr);
510 	iowrite8(CR_CMD_RESET_RX, &channel->regs->w.cr);
511 	iowrite8(CR_CMD_RESET_TX, &channel->regs->w.cr);
512 	iowrite8(CR_CMD_RESET_ERR_STATUS, &channel->regs->w.cr);
513 	iowrite8(CR_CMD_RESET_MR, &channel->regs->w.cr);
514 
515 	/* Set Bits per chars */
516 	switch (cflag & CSIZE) {
517 	case CS6:
518 		mr1 |= MR1_CHRL_6_BITS;
519 		break;
520 	case CS7:
521 		mr1 |= MR1_CHRL_7_BITS;
522 		break;
523 	case CS8:
524 	default:
525 		mr1 |= MR1_CHRL_8_BITS;
526 		/* By default, select CS8 */
527 		tty->termios.c_cflag = (cflag & ~CSIZE) | CS8;
528 		break;
529 	}
530 
531 	/* Set Parity */
532 	if (cflag & PARENB)
533 		if (cflag & PARODD)
534 			mr1 |= MR1_PARITY_ON | MR1_PARITY_ODD;
535 		else
536 			mr1 |= MR1_PARITY_ON | MR1_PARITY_EVEN;
537 	else
538 		mr1 |= MR1_PARITY_OFF;
539 
540 	/* Mark or space parity is not supported */
541 	tty->termios.c_cflag &= ~CMSPAR;
542 
543 	/* Set stop bits */
544 	if (cflag & CSTOPB)
545 		mr2 |= MR2_STOP_BITS_LENGTH_2;
546 	else
547 		mr2 |= MR2_STOP_BITS_LENGTH_1;
548 
549 	/* Set the flow control */
550 	switch (channel->board_id) {
551 	case IPACK1_DEVICE_ID_SBS_OCTAL_232:
552 		if (cflag & CRTSCTS) {
553 			mr1 |= MR1_RxRTS_CONTROL_ON;
554 			mr2 |= MR2_TxRTS_CONTROL_OFF | MR2_CTS_ENABLE_TX_ON;
555 		} else {
556 			mr1 |= MR1_RxRTS_CONTROL_OFF;
557 			mr2 |= MR2_TxRTS_CONTROL_OFF | MR2_CTS_ENABLE_TX_OFF;
558 		}
559 		break;
560 	case IPACK1_DEVICE_ID_SBS_OCTAL_422:
561 		mr1 |= MR1_RxRTS_CONTROL_OFF;
562 		mr2 |= MR2_TxRTS_CONTROL_OFF | MR2_CTS_ENABLE_TX_OFF;
563 		break;
564 	case IPACK1_DEVICE_ID_SBS_OCTAL_485:
565 		mr1 |= MR1_RxRTS_CONTROL_OFF;
566 		mr2 |= MR2_TxRTS_CONTROL_ON | MR2_CTS_ENABLE_TX_OFF;
567 		break;
568 	default:
569 		return;
570 		break;
571 	}
572 
573 	baud = tty_get_baud_rate(tty);
574 	tty_termios_encode_baud_rate(&tty->termios, baud, baud);
575 
576 	/* Set baud rate */
577 	switch (baud) {
578 	case 75:
579 		csr |= TX_CLK_75 | RX_CLK_75;
580 		break;
581 	case 110:
582 		csr |= TX_CLK_110 | RX_CLK_110;
583 		break;
584 	case 150:
585 		csr |= TX_CLK_150 | RX_CLK_150;
586 		break;
587 	case 300:
588 		csr |= TX_CLK_300 | RX_CLK_300;
589 		break;
590 	case 600:
591 		csr |= TX_CLK_600 | RX_CLK_600;
592 		break;
593 	case 1200:
594 		csr |= TX_CLK_1200 | RX_CLK_1200;
595 		break;
596 	case 1800:
597 		csr |= TX_CLK_1800 | RX_CLK_1800;
598 		break;
599 	case 2000:
600 		csr |= TX_CLK_2000 | RX_CLK_2000;
601 		break;
602 	case 2400:
603 		csr |= TX_CLK_2400 | RX_CLK_2400;
604 		break;
605 	case 4800:
606 		csr |= TX_CLK_4800  | RX_CLK_4800;
607 		break;
608 	case 9600:
609 		csr |= TX_CLK_9600  | RX_CLK_9600;
610 		break;
611 	case 19200:
612 		csr |= TX_CLK_19200 | RX_CLK_19200;
613 		break;
614 	case 38400:
615 	default:
616 		csr |= TX_CLK_38400 | RX_CLK_38400;
617 		/* In case of default, we establish 38400 bps */
618 		tty_termios_encode_baud_rate(&tty->termios, 38400, 38400);
619 		break;
620 	}
621 
622 	mr1 |= MR1_ERROR_CHAR;
623 	mr1 |= MR1_RxINT_RxRDY;
624 
625 	/* Write the control registers */
626 	iowrite8(mr1, &channel->regs->w.mr);
627 	iowrite8(mr2, &channel->regs->w.mr);
628 	iowrite8(csr, &channel->regs->w.csr);
629 
630 	/* Enable again the RX */
631 	iowrite8(CR_ENABLE_RX, &channel->regs->w.cr);
632 }
633 
634 static void ipoctal_hangup(struct tty_struct *tty)
635 {
636 	unsigned long flags;
637 	struct ipoctal_channel *channel = tty->driver_data;
638 
639 	if (channel == NULL)
640 		return;
641 
642 	spin_lock_irqsave(&channel->lock, flags);
643 	channel->nb_bytes = 0;
644 	channel->pointer_read = 0;
645 	channel->pointer_write = 0;
646 	spin_unlock_irqrestore(&channel->lock, flags);
647 
648 	tty_port_hangup(&channel->tty_port);
649 
650 	iowrite8(CR_DISABLE_RX | CR_DISABLE_TX, &channel->regs->w.cr);
651 	iowrite8(CR_CMD_RESET_RX, &channel->regs->w.cr);
652 	iowrite8(CR_CMD_RESET_TX, &channel->regs->w.cr);
653 	iowrite8(CR_CMD_RESET_ERR_STATUS, &channel->regs->w.cr);
654 	iowrite8(CR_CMD_RESET_MR, &channel->regs->w.cr);
655 
656 	clear_bit(ASYNCB_INITIALIZED, &channel->tty_port.flags);
657 	wake_up_interruptible(&channel->tty_port.open_wait);
658 }
659 
660 static const struct tty_operations ipoctal_fops = {
661 	.ioctl =		NULL,
662 	.open =			ipoctal_open,
663 	.close =		ipoctal_close,
664 	.write =		ipoctal_write_tty,
665 	.set_termios =		ipoctal_set_termios,
666 	.write_room =		ipoctal_write_room,
667 	.chars_in_buffer =	ipoctal_chars_in_buffer,
668 	.get_icount =		ipoctal_get_icount,
669 	.hangup =		ipoctal_hangup,
670 };
671 
672 static int ipoctal_probe(struct ipack_device *dev)
673 {
674 	int res;
675 	struct ipoctal *ipoctal;
676 
677 	ipoctal = kzalloc(sizeof(struct ipoctal), GFP_KERNEL);
678 	if (ipoctal == NULL)
679 		return -ENOMEM;
680 
681 	ipoctal->dev = dev;
682 	res = ipoctal_inst_slot(ipoctal, dev->bus->bus_nr, dev->slot);
683 	if (res)
684 		goto out_uninst;
685 
686 	dev_set_drvdata(&dev->dev, ipoctal);
687 	return 0;
688 
689 out_uninst:
690 	kfree(ipoctal);
691 	return res;
692 }
693 
694 static void __ipoctal_remove(struct ipoctal *ipoctal)
695 {
696 	int i;
697 
698 	ipoctal->dev->bus->ops->free_irq(ipoctal->dev);
699 
700 	for (i = 0; i < NR_CHANNELS; i++) {
701 		struct ipoctal_channel *channel = &ipoctal->channel[i];
702 		tty_unregister_device(ipoctal->tty_drv, i);
703 		tty_port_free_xmit_buf(&channel->tty_port);
704 		tty_port_destroy(&channel->tty_port);
705 	}
706 
707 	tty_unregister_driver(ipoctal->tty_drv);
708 	put_tty_driver(ipoctal->tty_drv);
709 	kfree(ipoctal);
710 }
711 
712 static void ipoctal_remove(struct ipack_device *idev)
713 {
714 	__ipoctal_remove(dev_get_drvdata(&idev->dev));
715 }
716 
717 static DEFINE_IPACK_DEVICE_TABLE(ipoctal_ids) = {
718 	{ IPACK_DEVICE(IPACK_ID_VERSION_1, IPACK1_VENDOR_ID_SBS,
719 			IPACK1_DEVICE_ID_SBS_OCTAL_232) },
720 	{ IPACK_DEVICE(IPACK_ID_VERSION_1, IPACK1_VENDOR_ID_SBS,
721 			IPACK1_DEVICE_ID_SBS_OCTAL_422) },
722 	{ IPACK_DEVICE(IPACK_ID_VERSION_1, IPACK1_VENDOR_ID_SBS,
723 			IPACK1_DEVICE_ID_SBS_OCTAL_485) },
724 	{ 0, },
725 };
726 
727 MODULE_DEVICE_TABLE(ipack, ipoctal_ids);
728 
729 static const struct ipack_driver_ops ipoctal_drv_ops = {
730 	.probe  = ipoctal_probe,
731 	.remove = ipoctal_remove,
732 };
733 
734 static struct ipack_driver driver = {
735 	.ops      = &ipoctal_drv_ops,
736 	.id_table = ipoctal_ids,
737 };
738 
739 static int __init ipoctal_init(void)
740 {
741 	return ipack_driver_register(&driver, THIS_MODULE, KBUILD_MODNAME);
742 }
743 
744 static void __exit ipoctal_exit(void)
745 {
746 	ipack_driver_unregister(&driver);
747 }
748 
749 MODULE_DESCRIPTION("IP-Octal 232, 422 and 485 device driver");
750 MODULE_LICENSE("GPL");
751 
752 module_init(ipoctal_init);
753 module_exit(ipoctal_exit);
754