xref: /openbmc/linux/drivers/ipack/devices/ipoctal.c (revision 588b48ca)
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/io.h>
24 #include <linux/ipack.h>
25 #include "ipoctal.h"
26 #include "scc2698.h"
27 
28 #define IP_OCTAL_ID_SPACE_VECTOR    0x41
29 #define IP_OCTAL_NB_BLOCKS          4
30 
31 static const struct tty_operations ipoctal_fops;
32 
33 struct ipoctal_channel {
34 	struct ipoctal_stats		stats;
35 	unsigned int			nb_bytes;
36 	wait_queue_head_t		queue;
37 	spinlock_t			lock;
38 	unsigned int			pointer_read;
39 	unsigned int			pointer_write;
40 	struct tty_port			tty_port;
41 	union scc2698_channel __iomem	*regs;
42 	union scc2698_block __iomem	*block_regs;
43 	unsigned int			board_id;
44 	u8				isr_rx_rdy_mask;
45 	u8				isr_tx_rdy_mask;
46 	unsigned int			rx_enable;
47 };
48 
49 struct ipoctal {
50 	struct ipack_device		*dev;
51 	unsigned int			board_id;
52 	struct ipoctal_channel		channel[NR_CHANNELS];
53 	struct tty_driver		*tty_drv;
54 	u8 __iomem			*mem8_space;
55 	u8 __iomem			*int_space;
56 };
57 
58 static int ipoctal_port_activate(struct tty_port *port, struct tty_struct *tty)
59 {
60 	struct ipoctal_channel *channel;
61 
62 	channel = dev_get_drvdata(tty->dev);
63 
64 	/*
65 	 * Enable RX. TX will be enabled when
66 	 * there is something to send
67 	 */
68 	iowrite8(CR_ENABLE_RX, &channel->regs->w.cr);
69 	channel->rx_enable = 1;
70 	return 0;
71 }
72 
73 static int ipoctal_open(struct tty_struct *tty, struct file *file)
74 {
75 	struct ipoctal_channel *channel;
76 
77 	channel = dev_get_drvdata(tty->dev);
78 	tty->driver_data = channel;
79 
80 	return tty_port_open(&channel->tty_port, tty, file);
81 }
82 
83 static void ipoctal_reset_stats(struct ipoctal_stats *stats)
84 {
85 	stats->tx = 0;
86 	stats->rx = 0;
87 	stats->rcv_break = 0;
88 	stats->framing_err = 0;
89 	stats->overrun_err = 0;
90 	stats->parity_err = 0;
91 }
92 
93 static void ipoctal_free_channel(struct ipoctal_channel *channel)
94 {
95 	ipoctal_reset_stats(&channel->stats);
96 	channel->pointer_read = 0;
97 	channel->pointer_write = 0;
98 	channel->nb_bytes = 0;
99 }
100 
101 static void ipoctal_close(struct tty_struct *tty, struct file *filp)
102 {
103 	struct ipoctal_channel *channel = tty->driver_data;
104 
105 	tty_port_close(&channel->tty_port, tty, filp);
106 	ipoctal_free_channel(channel);
107 }
108 
109 static int ipoctal_get_icount(struct tty_struct *tty,
110 			      struct serial_icounter_struct *icount)
111 {
112 	struct ipoctal_channel *channel = tty->driver_data;
113 
114 	icount->cts = 0;
115 	icount->dsr = 0;
116 	icount->rng = 0;
117 	icount->dcd = 0;
118 	icount->rx = channel->stats.rx;
119 	icount->tx = channel->stats.tx;
120 	icount->frame = channel->stats.framing_err;
121 	icount->parity = channel->stats.parity_err;
122 	icount->brk = channel->stats.rcv_break;
123 	return 0;
124 }
125 
126 static void ipoctal_irq_rx(struct ipoctal_channel *channel, u8 sr)
127 {
128 	struct tty_port *port = &channel->tty_port;
129 	unsigned char value;
130 	unsigned char flag;
131 	u8 isr;
132 
133 	do {
134 		value = ioread8(&channel->regs->r.rhr);
135 		flag = TTY_NORMAL;
136 		/* Error: count statistics */
137 		if (sr & SR_ERROR) {
138 			iowrite8(CR_CMD_RESET_ERR_STATUS, &channel->regs->w.cr);
139 
140 			if (sr & SR_OVERRUN_ERROR) {
141 				channel->stats.overrun_err++;
142 				/* Overrun doesn't affect the current character*/
143 				tty_insert_flip_char(port, 0, TTY_OVERRUN);
144 			}
145 			if (sr & SR_PARITY_ERROR) {
146 				channel->stats.parity_err++;
147 				flag = TTY_PARITY;
148 			}
149 			if (sr & SR_FRAMING_ERROR) {
150 				channel->stats.framing_err++;
151 				flag = TTY_FRAME;
152 			}
153 			if (sr & SR_RECEIVED_BREAK) {
154 				iowrite8(CR_CMD_RESET_BREAK_CHANGE, &channel->regs->w.cr);
155 				channel->stats.rcv_break++;
156 				flag = TTY_BREAK;
157 			}
158 		}
159 		tty_insert_flip_char(port, value, flag);
160 
161 		/* Check if there are more characters in RX FIFO
162 		 * If there are more, the isr register for this channel
163 		 * has enabled the RxRDY|FFULL bit.
164 		 */
165 		isr = ioread8(&channel->block_regs->r.isr);
166 		sr = ioread8(&channel->regs->r.sr);
167 	} while (isr & channel->isr_rx_rdy_mask);
168 
169 	tty_flip_buffer_push(port);
170 }
171 
172 static void ipoctal_irq_tx(struct ipoctal_channel *channel)
173 {
174 	unsigned char value;
175 	unsigned int *pointer_write = &channel->pointer_write;
176 
177 	if (channel->nb_bytes == 0)
178 		return;
179 
180 	spin_lock(&channel->lock);
181 	value = channel->tty_port.xmit_buf[*pointer_write];
182 	iowrite8(value, &channel->regs->w.thr);
183 	channel->stats.tx++;
184 	(*pointer_write)++;
185 	*pointer_write = *pointer_write % PAGE_SIZE;
186 	channel->nb_bytes--;
187 	spin_unlock(&channel->lock);
188 }
189 
190 static void ipoctal_irq_channel(struct ipoctal_channel *channel)
191 {
192 	u8 isr, sr;
193 
194 	/* The HW is organized in pair of channels.  See which register we need
195 	 * to read from */
196 	isr = ioread8(&channel->block_regs->r.isr);
197 	sr = ioread8(&channel->regs->r.sr);
198 
199 	if ((sr & SR_TX_EMPTY) && (channel->nb_bytes == 0)) {
200 		iowrite8(CR_DISABLE_TX, &channel->regs->w.cr);
201 		/* In case of RS-485, change from TX to RX when finishing TX.
202 		 * Half-duplex. */
203 		if (channel->board_id == IPACK1_DEVICE_ID_SBS_OCTAL_485) {
204 			iowrite8(CR_CMD_NEGATE_RTSN, &channel->regs->w.cr);
205 			iowrite8(CR_ENABLE_RX, &channel->regs->w.cr);
206 			channel->rx_enable = 1;
207 		}
208 	}
209 
210 	/* RX data */
211 	if ((isr & channel->isr_rx_rdy_mask) && (sr & SR_RX_READY))
212 		ipoctal_irq_rx(channel, sr);
213 
214 	/* TX of each character */
215 	if ((isr & channel->isr_tx_rdy_mask) && (sr & SR_TX_READY))
216 		ipoctal_irq_tx(channel);
217 }
218 
219 static irqreturn_t ipoctal_irq_handler(void *arg)
220 {
221 	unsigned int i;
222 	struct ipoctal *ipoctal = (struct ipoctal *) arg;
223 
224 	/* Clear the IPack device interrupt */
225 	readw(ipoctal->int_space + ACK_INT_REQ0);
226 	readw(ipoctal->int_space + ACK_INT_REQ1);
227 
228 	/* Check all channels */
229 	for (i = 0; i < NR_CHANNELS; i++)
230 		ipoctal_irq_channel(&ipoctal->channel[i]);
231 
232 	return IRQ_HANDLED;
233 }
234 
235 static const struct tty_port_operations ipoctal_tty_port_ops = {
236 	.dtr_rts = NULL,
237 	.activate = ipoctal_port_activate,
238 };
239 
240 static int ipoctal_inst_slot(struct ipoctal *ipoctal, unsigned int bus_nr,
241 			     unsigned int slot)
242 {
243 	int res;
244 	int i;
245 	struct tty_driver *tty;
246 	char name[20];
247 	struct ipoctal_channel *channel;
248 	struct ipack_region *region;
249 	void __iomem *addr;
250 	union scc2698_channel __iomem *chan_regs;
251 	union scc2698_block __iomem *block_regs;
252 
253 	ipoctal->board_id = ipoctal->dev->id_device;
254 
255 	region = &ipoctal->dev->region[IPACK_IO_SPACE];
256 	addr = devm_ioremap_nocache(&ipoctal->dev->dev,
257 				    region->start, region->size);
258 	if (!addr) {
259 		dev_err(&ipoctal->dev->dev,
260 			"Unable to map slot [%d:%d] IO space!\n",
261 			bus_nr, slot);
262 		return -EADDRNOTAVAIL;
263 	}
264 	/* Save the virtual address to access the registers easily */
265 	chan_regs =
266 		(union scc2698_channel __iomem *) addr;
267 	block_regs =
268 		(union scc2698_block __iomem *) addr;
269 
270 	region = &ipoctal->dev->region[IPACK_INT_SPACE];
271 	ipoctal->int_space =
272 		devm_ioremap_nocache(&ipoctal->dev->dev,
273 				     region->start, region->size);
274 	if (!ipoctal->int_space) {
275 		dev_err(&ipoctal->dev->dev,
276 			"Unable to map slot [%d:%d] INT space!\n",
277 			bus_nr, slot);
278 		return -EADDRNOTAVAIL;
279 	}
280 
281 	region = &ipoctal->dev->region[IPACK_MEM8_SPACE];
282 	ipoctal->mem8_space =
283 		devm_ioremap_nocache(&ipoctal->dev->dev,
284 				     region->start, 0x8000);
285 	if (!ipoctal->mem8_space) {
286 		dev_err(&ipoctal->dev->dev,
287 			"Unable to map slot [%d:%d] MEM8 space!\n",
288 			bus_nr, slot);
289 		return -EADDRNOTAVAIL;
290 	}
291 
292 
293 	/* Disable RX and TX before touching anything */
294 	for (i = 0; i < NR_CHANNELS ; i++) {
295 		struct ipoctal_channel *channel = &ipoctal->channel[i];
296 		channel->regs = chan_regs + i;
297 		channel->block_regs = block_regs + (i >> 1);
298 		channel->board_id = ipoctal->board_id;
299 		if (i & 1) {
300 			channel->isr_tx_rdy_mask = ISR_TxRDY_B;
301 			channel->isr_rx_rdy_mask = ISR_RxRDY_FFULL_B;
302 		} else {
303 			channel->isr_tx_rdy_mask = ISR_TxRDY_A;
304 			channel->isr_rx_rdy_mask = ISR_RxRDY_FFULL_A;
305 		}
306 
307 		iowrite8(CR_DISABLE_RX | CR_DISABLE_TX, &channel->regs->w.cr);
308 		channel->rx_enable = 0;
309 		iowrite8(CR_CMD_RESET_RX, &channel->regs->w.cr);
310 		iowrite8(CR_CMD_RESET_TX, &channel->regs->w.cr);
311 		iowrite8(MR1_CHRL_8_BITS | MR1_ERROR_CHAR | MR1_RxINT_RxRDY,
312 			 &channel->regs->w.mr); /* mr1 */
313 		iowrite8(0, &channel->regs->w.mr); /* mr2 */
314 		iowrite8(TX_CLK_9600  | RX_CLK_9600, &channel->regs->w.csr);
315 	}
316 
317 	for (i = 0; i < IP_OCTAL_NB_BLOCKS; i++) {
318 		iowrite8(ACR_BRG_SET2, &block_regs[i].w.acr);
319 		iowrite8(OPCR_MPP_OUTPUT | OPCR_MPOa_RTSN | OPCR_MPOb_RTSN,
320 			 &block_regs[i].w.opcr);
321 		iowrite8(IMR_TxRDY_A | IMR_RxRDY_FFULL_A | IMR_DELTA_BREAK_A |
322 			 IMR_TxRDY_B | IMR_RxRDY_FFULL_B | IMR_DELTA_BREAK_B,
323 			 &block_regs[i].w.imr);
324 	}
325 
326 	/* Dummy write */
327 	iowrite8(1, ipoctal->mem8_space + 1);
328 
329 	/* Register the TTY device */
330 
331 	/* Each IP-OCTAL channel is a TTY port */
332 	tty = alloc_tty_driver(NR_CHANNELS);
333 
334 	if (!tty)
335 		return -ENOMEM;
336 
337 	/* Fill struct tty_driver with ipoctal data */
338 	tty->owner = THIS_MODULE;
339 	tty->driver_name = KBUILD_MODNAME;
340 	sprintf(name, KBUILD_MODNAME ".%d.%d.", bus_nr, slot);
341 	tty->name = name;
342 	tty->major = 0;
343 
344 	tty->minor_start = 0;
345 	tty->type = TTY_DRIVER_TYPE_SERIAL;
346 	tty->subtype = SERIAL_TYPE_NORMAL;
347 	tty->flags = TTY_DRIVER_REAL_RAW | TTY_DRIVER_DYNAMIC_DEV;
348 	tty->init_termios = tty_std_termios;
349 	tty->init_termios.c_cflag = B9600 | CS8 | CREAD | HUPCL | CLOCAL;
350 	tty->init_termios.c_ispeed = 9600;
351 	tty->init_termios.c_ospeed = 9600;
352 
353 	tty_set_operations(tty, &ipoctal_fops);
354 	res = tty_register_driver(tty);
355 	if (res) {
356 		dev_err(&ipoctal->dev->dev, "Can't register tty driver.\n");
357 		put_tty_driver(tty);
358 		return res;
359 	}
360 
361 	/* Save struct tty_driver for use it when uninstalling the device */
362 	ipoctal->tty_drv = tty;
363 
364 	for (i = 0; i < NR_CHANNELS; i++) {
365 		struct device *tty_dev;
366 
367 		channel = &ipoctal->channel[i];
368 		tty_port_init(&channel->tty_port);
369 		tty_port_alloc_xmit_buf(&channel->tty_port);
370 		channel->tty_port.ops = &ipoctal_tty_port_ops;
371 
372 		ipoctal_reset_stats(&channel->stats);
373 		channel->nb_bytes = 0;
374 		spin_lock_init(&channel->lock);
375 		channel->pointer_read = 0;
376 		channel->pointer_write = 0;
377 		tty_dev = tty_port_register_device(&channel->tty_port, tty, i, NULL);
378 		if (IS_ERR(tty_dev)) {
379 			dev_err(&ipoctal->dev->dev, "Failed to register tty device.\n");
380 			tty_port_destroy(&channel->tty_port);
381 			continue;
382 		}
383 		dev_set_drvdata(tty_dev, channel);
384 	}
385 
386 	/*
387 	 * IP-OCTAL has different addresses to copy its IRQ vector.
388 	 * Depending of the carrier these addresses are accesible or not.
389 	 * More info in the datasheet.
390 	 */
391 	ipoctal->dev->bus->ops->request_irq(ipoctal->dev,
392 				       ipoctal_irq_handler, ipoctal);
393 
394 	return 0;
395 }
396 
397 static inline int ipoctal_copy_write_buffer(struct ipoctal_channel *channel,
398 					    const unsigned char *buf,
399 					    int count)
400 {
401 	unsigned long flags;
402 	int i;
403 	unsigned int *pointer_read = &channel->pointer_read;
404 
405 	/* Copy the bytes from the user buffer to the internal one */
406 	for (i = 0; i < count; i++) {
407 		if (i <= (PAGE_SIZE - channel->nb_bytes)) {
408 			spin_lock_irqsave(&channel->lock, flags);
409 			channel->tty_port.xmit_buf[*pointer_read] = buf[i];
410 			*pointer_read = (*pointer_read + 1) % PAGE_SIZE;
411 			channel->nb_bytes++;
412 			spin_unlock_irqrestore(&channel->lock, flags);
413 		} else {
414 			break;
415 		}
416 	}
417 	return i;
418 }
419 
420 static int ipoctal_write_tty(struct tty_struct *tty,
421 			     const unsigned char *buf, int count)
422 {
423 	struct ipoctal_channel *channel = tty->driver_data;
424 	unsigned int char_copied;
425 
426 	char_copied = ipoctal_copy_write_buffer(channel, buf, count);
427 
428 	/* As the IP-OCTAL 485 only supports half duplex, do it manually */
429 	if (channel->board_id == IPACK1_DEVICE_ID_SBS_OCTAL_485) {
430 		iowrite8(CR_DISABLE_RX, &channel->regs->w.cr);
431 		channel->rx_enable = 0;
432 		iowrite8(CR_CMD_ASSERT_RTSN, &channel->regs->w.cr);
433 	}
434 
435 	/*
436 	 * Send a packet and then disable TX to avoid failure after several send
437 	 * operations
438 	 */
439 	iowrite8(CR_ENABLE_TX, &channel->regs->w.cr);
440 	return char_copied;
441 }
442 
443 static int ipoctal_write_room(struct tty_struct *tty)
444 {
445 	struct ipoctal_channel *channel = tty->driver_data;
446 
447 	return PAGE_SIZE - channel->nb_bytes;
448 }
449 
450 static int ipoctal_chars_in_buffer(struct tty_struct *tty)
451 {
452 	struct ipoctal_channel *channel = tty->driver_data;
453 
454 	return channel->nb_bytes;
455 }
456 
457 static void ipoctal_set_termios(struct tty_struct *tty,
458 				struct ktermios *old_termios)
459 {
460 	unsigned int cflag;
461 	unsigned char mr1 = 0;
462 	unsigned char mr2 = 0;
463 	unsigned char csr = 0;
464 	struct ipoctal_channel *channel = tty->driver_data;
465 	speed_t baud;
466 
467 	cflag = tty->termios.c_cflag;
468 
469 	/* Disable and reset everything before change the setup */
470 	iowrite8(CR_DISABLE_RX | CR_DISABLE_TX, &channel->regs->w.cr);
471 	iowrite8(CR_CMD_RESET_RX, &channel->regs->w.cr);
472 	iowrite8(CR_CMD_RESET_TX, &channel->regs->w.cr);
473 	iowrite8(CR_CMD_RESET_ERR_STATUS, &channel->regs->w.cr);
474 	iowrite8(CR_CMD_RESET_MR, &channel->regs->w.cr);
475 
476 	/* Set Bits per chars */
477 	switch (cflag & CSIZE) {
478 	case CS6:
479 		mr1 |= MR1_CHRL_6_BITS;
480 		break;
481 	case CS7:
482 		mr1 |= MR1_CHRL_7_BITS;
483 		break;
484 	case CS8:
485 	default:
486 		mr1 |= MR1_CHRL_8_BITS;
487 		/* By default, select CS8 */
488 		tty->termios.c_cflag = (cflag & ~CSIZE) | CS8;
489 		break;
490 	}
491 
492 	/* Set Parity */
493 	if (cflag & PARENB)
494 		if (cflag & PARODD)
495 			mr1 |= MR1_PARITY_ON | MR1_PARITY_ODD;
496 		else
497 			mr1 |= MR1_PARITY_ON | MR1_PARITY_EVEN;
498 	else
499 		mr1 |= MR1_PARITY_OFF;
500 
501 	/* Mark or space parity is not supported */
502 	tty->termios.c_cflag &= ~CMSPAR;
503 
504 	/* Set stop bits */
505 	if (cflag & CSTOPB)
506 		mr2 |= MR2_STOP_BITS_LENGTH_2;
507 	else
508 		mr2 |= MR2_STOP_BITS_LENGTH_1;
509 
510 	/* Set the flow control */
511 	switch (channel->board_id) {
512 	case IPACK1_DEVICE_ID_SBS_OCTAL_232:
513 		if (cflag & CRTSCTS) {
514 			mr1 |= MR1_RxRTS_CONTROL_ON;
515 			mr2 |= MR2_TxRTS_CONTROL_OFF | MR2_CTS_ENABLE_TX_ON;
516 		} else {
517 			mr1 |= MR1_RxRTS_CONTROL_OFF;
518 			mr2 |= MR2_TxRTS_CONTROL_OFF | MR2_CTS_ENABLE_TX_OFF;
519 		}
520 		break;
521 	case IPACK1_DEVICE_ID_SBS_OCTAL_422:
522 		mr1 |= MR1_RxRTS_CONTROL_OFF;
523 		mr2 |= MR2_TxRTS_CONTROL_OFF | MR2_CTS_ENABLE_TX_OFF;
524 		break;
525 	case IPACK1_DEVICE_ID_SBS_OCTAL_485:
526 		mr1 |= MR1_RxRTS_CONTROL_OFF;
527 		mr2 |= MR2_TxRTS_CONTROL_ON | MR2_CTS_ENABLE_TX_OFF;
528 		break;
529 	default:
530 		return;
531 		break;
532 	}
533 
534 	baud = tty_get_baud_rate(tty);
535 	tty_termios_encode_baud_rate(&tty->termios, baud, baud);
536 
537 	/* Set baud rate */
538 	switch (baud) {
539 	case 75:
540 		csr |= TX_CLK_75 | RX_CLK_75;
541 		break;
542 	case 110:
543 		csr |= TX_CLK_110 | RX_CLK_110;
544 		break;
545 	case 150:
546 		csr |= TX_CLK_150 | RX_CLK_150;
547 		break;
548 	case 300:
549 		csr |= TX_CLK_300 | RX_CLK_300;
550 		break;
551 	case 600:
552 		csr |= TX_CLK_600 | RX_CLK_600;
553 		break;
554 	case 1200:
555 		csr |= TX_CLK_1200 | RX_CLK_1200;
556 		break;
557 	case 1800:
558 		csr |= TX_CLK_1800 | RX_CLK_1800;
559 		break;
560 	case 2000:
561 		csr |= TX_CLK_2000 | RX_CLK_2000;
562 		break;
563 	case 2400:
564 		csr |= TX_CLK_2400 | RX_CLK_2400;
565 		break;
566 	case 4800:
567 		csr |= TX_CLK_4800  | RX_CLK_4800;
568 		break;
569 	case 9600:
570 		csr |= TX_CLK_9600  | RX_CLK_9600;
571 		break;
572 	case 19200:
573 		csr |= TX_CLK_19200 | RX_CLK_19200;
574 		break;
575 	case 38400:
576 	default:
577 		csr |= TX_CLK_38400 | RX_CLK_38400;
578 		/* In case of default, we establish 38400 bps */
579 		tty_termios_encode_baud_rate(&tty->termios, 38400, 38400);
580 		break;
581 	}
582 
583 	mr1 |= MR1_ERROR_CHAR;
584 	mr1 |= MR1_RxINT_RxRDY;
585 
586 	/* Write the control registers */
587 	iowrite8(mr1, &channel->regs->w.mr);
588 	iowrite8(mr2, &channel->regs->w.mr);
589 	iowrite8(csr, &channel->regs->w.csr);
590 
591 	/* Enable again the RX, if it was before */
592 	if (channel->rx_enable)
593 		iowrite8(CR_ENABLE_RX, &channel->regs->w.cr);
594 }
595 
596 static void ipoctal_hangup(struct tty_struct *tty)
597 {
598 	unsigned long flags;
599 	struct ipoctal_channel *channel = tty->driver_data;
600 
601 	if (channel == NULL)
602 		return;
603 
604 	spin_lock_irqsave(&channel->lock, flags);
605 	channel->nb_bytes = 0;
606 	channel->pointer_read = 0;
607 	channel->pointer_write = 0;
608 	spin_unlock_irqrestore(&channel->lock, flags);
609 
610 	tty_port_hangup(&channel->tty_port);
611 
612 	iowrite8(CR_DISABLE_RX | CR_DISABLE_TX, &channel->regs->w.cr);
613 	channel->rx_enable = 0;
614 	iowrite8(CR_CMD_RESET_RX, &channel->regs->w.cr);
615 	iowrite8(CR_CMD_RESET_TX, &channel->regs->w.cr);
616 	iowrite8(CR_CMD_RESET_ERR_STATUS, &channel->regs->w.cr);
617 	iowrite8(CR_CMD_RESET_MR, &channel->regs->w.cr);
618 
619 	clear_bit(ASYNCB_INITIALIZED, &channel->tty_port.flags);
620 	wake_up_interruptible(&channel->tty_port.open_wait);
621 }
622 
623 static void ipoctal_shutdown(struct tty_struct *tty)
624 {
625 	struct ipoctal_channel *channel = tty->driver_data;
626 
627 	if (channel == NULL)
628 		return;
629 
630 	iowrite8(CR_DISABLE_RX | CR_DISABLE_TX, &channel->regs->w.cr);
631 	channel->rx_enable = 0;
632 	iowrite8(CR_CMD_RESET_RX, &channel->regs->w.cr);
633 	iowrite8(CR_CMD_RESET_TX, &channel->regs->w.cr);
634 	iowrite8(CR_CMD_RESET_ERR_STATUS, &channel->regs->w.cr);
635 	iowrite8(CR_CMD_RESET_MR, &channel->regs->w.cr);
636 	clear_bit(ASYNCB_INITIALIZED, &channel->tty_port.flags);
637 }
638 
639 static const struct tty_operations ipoctal_fops = {
640 	.ioctl =		NULL,
641 	.open =			ipoctal_open,
642 	.close =		ipoctal_close,
643 	.write =		ipoctal_write_tty,
644 	.set_termios =		ipoctal_set_termios,
645 	.write_room =		ipoctal_write_room,
646 	.chars_in_buffer =	ipoctal_chars_in_buffer,
647 	.get_icount =		ipoctal_get_icount,
648 	.hangup =		ipoctal_hangup,
649 	.shutdown =		ipoctal_shutdown,
650 };
651 
652 static int ipoctal_probe(struct ipack_device *dev)
653 {
654 	int res;
655 	struct ipoctal *ipoctal;
656 
657 	ipoctal = kzalloc(sizeof(struct ipoctal), GFP_KERNEL);
658 	if (ipoctal == NULL)
659 		return -ENOMEM;
660 
661 	ipoctal->dev = dev;
662 	res = ipoctal_inst_slot(ipoctal, dev->bus->bus_nr, dev->slot);
663 	if (res)
664 		goto out_uninst;
665 
666 	dev_set_drvdata(&dev->dev, ipoctal);
667 	return 0;
668 
669 out_uninst:
670 	kfree(ipoctal);
671 	return res;
672 }
673 
674 static void __ipoctal_remove(struct ipoctal *ipoctal)
675 {
676 	int i;
677 
678 	ipoctal->dev->bus->ops->free_irq(ipoctal->dev);
679 
680 	for (i = 0; i < NR_CHANNELS; i++) {
681 		struct ipoctal_channel *channel = &ipoctal->channel[i];
682 		tty_unregister_device(ipoctal->tty_drv, i);
683 		tty_port_free_xmit_buf(&channel->tty_port);
684 		tty_port_destroy(&channel->tty_port);
685 	}
686 
687 	tty_unregister_driver(ipoctal->tty_drv);
688 	put_tty_driver(ipoctal->tty_drv);
689 	kfree(ipoctal);
690 }
691 
692 static void ipoctal_remove(struct ipack_device *idev)
693 {
694 	__ipoctal_remove(dev_get_drvdata(&idev->dev));
695 }
696 
697 static DEFINE_IPACK_DEVICE_TABLE(ipoctal_ids) = {
698 	{ IPACK_DEVICE(IPACK_ID_VERSION_1, IPACK1_VENDOR_ID_SBS,
699 			IPACK1_DEVICE_ID_SBS_OCTAL_232) },
700 	{ IPACK_DEVICE(IPACK_ID_VERSION_1, IPACK1_VENDOR_ID_SBS,
701 			IPACK1_DEVICE_ID_SBS_OCTAL_422) },
702 	{ IPACK_DEVICE(IPACK_ID_VERSION_1, IPACK1_VENDOR_ID_SBS,
703 			IPACK1_DEVICE_ID_SBS_OCTAL_485) },
704 	{ 0, },
705 };
706 
707 MODULE_DEVICE_TABLE(ipack, ipoctal_ids);
708 
709 static const struct ipack_driver_ops ipoctal_drv_ops = {
710 	.probe  = ipoctal_probe,
711 	.remove = ipoctal_remove,
712 };
713 
714 static struct ipack_driver driver = {
715 	.ops      = &ipoctal_drv_ops,
716 	.id_table = ipoctal_ids,
717 };
718 
719 static int __init ipoctal_init(void)
720 {
721 	return ipack_driver_register(&driver, THIS_MODULE, KBUILD_MODNAME);
722 }
723 
724 static void __exit ipoctal_exit(void)
725 {
726 	ipack_driver_unregister(&driver);
727 }
728 
729 MODULE_DESCRIPTION("IP-Octal 232, 422 and 485 device driver");
730 MODULE_LICENSE("GPL");
731 
732 module_init(ipoctal_init);
733 module_exit(ipoctal_exit);
734