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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * driver for the GE IP-OCTAL boards
4 *
5 * Copyright (C) 2009-2012 CERN (www.cern.ch)
6 * Author: Nicolas Serafini, EIC2 SA
7 * Author: Samuel Iglesias Gonsalvez <[email protected]>
8 */
9
10#include <linux/device.h>
11#include <linux/module.h>
12#include <linux/interrupt.h>
13#include <linux/kref.h>
14#include <linux/rwsem.h>
15#include <linux/sched.h>
16#include <linux/tty.h>
17#include <linux/serial.h>
18#include <linux/tty_flip.h>
19#include <linux/slab.h>
20#include <linux/io.h>
21#include <linux/ipack.h>
22#include "ipoctal.h"
23#include "scc2698.h"
24
25#define IP_OCTAL_ID_SPACE_VECTOR 0x41
26#define IP_OCTAL_NB_BLOCKS 4
27
28static const struct tty_operations ipoctal_fops;
29
30static void ipoctal_release(struct kref *kref);
31
32struct ipoctal_channel {
33 struct ipoctal_stats stats;
34 unsigned int nb_bytes;
35 wait_queue_head_t queue;
36 spinlock_t lock;
37 unsigned int pointer_read;
38 unsigned int pointer_write;
39 struct tty_port tty_port;
40 bool tty_registered;
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
49struct 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 struct kref kref;
57 struct module *carrier_owner;
58 struct rw_semaphore remove_sem;
59 bool removed;
60};
61
62static inline struct ipoctal *chan_to_ipoctal(struct ipoctal_channel *chan,
63 unsigned int index)
64{
65 return container_of(chan, struct ipoctal, channel[index]);
66}
67
68static void ipoctal_reset_channel(struct ipoctal_channel *channel)
69{
70 iowrite8(CR_DISABLE_RX | CR_DISABLE_TX, &channel->regs->w.cr);
71 channel->rx_enable = 0;
72 iowrite8(CR_CMD_RESET_RX, &channel->regs->w.cr);
73 iowrite8(CR_CMD_RESET_TX, &channel->regs->w.cr);
74 iowrite8(CR_CMD_RESET_ERR_STATUS, &channel->regs->w.cr);
75 iowrite8(CR_CMD_RESET_MR, &channel->regs->w.cr);
76}
77
78static int ipoctal_port_activate(struct tty_port *port, struct tty_struct *tty)
79{
80 struct ipoctal_channel *channel;
81 struct ipoctal *ipoctal;
82
83 channel = dev_get_drvdata(tty->dev);
84 ipoctal = chan_to_ipoctal(channel, tty->index);
85
86 guard(rwsem_read)(&ipoctal->remove_sem);
87 if (ipoctal->removed)
88 return -ENODEV;
89
90 /*
91 * Enable RX. TX will be enabled when
92 * there is something to send
93 */
94 iowrite8(CR_ENABLE_RX, &channel->regs->w.cr);
95 channel->rx_enable = 1;
96 return 0;
97}
98
99static int ipoctal_install(struct tty_driver *driver, struct tty_struct *tty)
100{
101 struct ipoctal_channel *channel = dev_get_drvdata(tty->dev);
102 struct ipoctal *ipoctal = chan_to_ipoctal(channel, tty->index);
103 int res;
104
105 if (!ipack_get_carrier(ipoctal->dev))
106 return -EBUSY;
107
108 res = tty_standard_install(driver, tty);
109 if (res)
110 goto err_put_carrier;
111
112 kref_get(&ipoctal->kref);
113 tty->driver_data = channel;
114
115 return 0;
116
117err_put_carrier:
118 ipack_put_carrier(ipoctal->dev);
119
120 return res;
121}
122
123static int ipoctal_open(struct tty_struct *tty, struct file *file)
124{
125 struct ipoctal_channel *channel = tty->driver_data;
126
127 return tty_port_open(&channel->tty_port, tty, file);
128}
129
130static void ipoctal_reset_stats(struct ipoctal_stats *stats)
131{
132 stats->tx = 0;
133 stats->rx = 0;
134 stats->rcv_break = 0;
135 stats->framing_err = 0;
136 stats->overrun_err = 0;
137 stats->parity_err = 0;
138}
139
140static void ipoctal_free_channel(struct ipoctal_channel *channel)
141{
142 ipoctal_reset_stats(&channel->stats);
143 channel->pointer_read = 0;
144 channel->pointer_write = 0;
145 channel->nb_bytes = 0;
146}
147
148static void ipoctal_close(struct tty_struct *tty, struct file *filp)
149{
150 struct ipoctal_channel *channel = tty->driver_data;
151
152 tty_port_close(&channel->tty_port, tty, filp);
153 ipoctal_free_channel(channel);
154}
155
156static int ipoctal_get_icount(struct tty_struct *tty,
157 struct serial_icounter_struct *icount)
158{
159 struct ipoctal_channel *channel = tty->driver_data;
160
161 icount->cts = 0;
162 icount->dsr = 0;
163 icount->rng = 0;
164 icount->dcd = 0;
165 icount->rx = channel->stats.rx;
166 icount->tx = channel->stats.tx;
167 icount->frame = channel->stats.framing_err;
168 icount->parity = channel->stats.parity_err;
169 icount->brk = channel->stats.rcv_break;
170 return 0;
171}
172
173static void ipoctal_irq_rx(struct ipoctal_channel *channel, u8 sr)
174{
175 struct tty_port *port = &channel->tty_port;
176 u8 isr, value, flag;
177
178 do {
179 value = ioread8(&channel->regs->r.rhr);
180 flag = TTY_NORMAL;
181 /* Error: count statistics */
182 if (sr & SR_ERROR) {
183 iowrite8(CR_CMD_RESET_ERR_STATUS, &channel->regs->w.cr);
184
185 if (sr & SR_OVERRUN_ERROR) {
186 channel->stats.overrun_err++;
187 /* Overrun doesn't affect the current character*/
188 tty_insert_flip_char(port, 0, TTY_OVERRUN);
189 }
190 if (sr & SR_PARITY_ERROR) {
191 channel->stats.parity_err++;
192 flag = TTY_PARITY;
193 }
194 if (sr & SR_FRAMING_ERROR) {
195 channel->stats.framing_err++;
196 flag = TTY_FRAME;
197 }
198 if (sr & SR_RECEIVED_BREAK) {
199 channel->stats.rcv_break++;
200 flag = TTY_BREAK;
201 }
202 }
203 tty_insert_flip_char(port, value, flag);
204
205 /* Check if there are more characters in RX FIFO
206 * If there are more, the isr register for this channel
207 * has enabled the RxRDY|FFULL bit.
208 */
209 isr = ioread8(&channel->block_regs->r.isr);
210 sr = ioread8(&channel->regs->r.sr);
211 } while (isr & channel->isr_rx_rdy_mask);
212
213 tty_flip_buffer_push(port);
214}
215
216static void ipoctal_irq_tx(struct ipoctal_channel *channel)
217{
218 unsigned int *pointer_write = &channel->pointer_write;
219 u8 value;
220
221 if (channel->nb_bytes == 0)
222 return;
223
224 spin_lock(&channel->lock);
225 value = channel->tty_port.xmit_buf[*pointer_write];
226 iowrite8(value, &channel->regs->w.thr);
227 channel->stats.tx++;
228 (*pointer_write)++;
229 *pointer_write = *pointer_write % PAGE_SIZE;
230 channel->nb_bytes--;
231 spin_unlock(&channel->lock);
232}
233
234static void ipoctal_irq_channel(struct ipoctal_channel *channel)
235{
236 u8 isr, sr;
237
238 /* The HW is organized in pair of channels. See which register we need
239 * to read from */
240 isr = ioread8(&channel->block_regs->r.isr);
241 sr = ioread8(&channel->regs->r.sr);
242
243 if (isr & (IMR_DELTA_BREAK_A | IMR_DELTA_BREAK_B))
244 iowrite8(CR_CMD_RESET_BREAK_CHANGE, &channel->regs->w.cr);
245
246 if ((sr & SR_TX_EMPTY) && (channel->nb_bytes == 0)) {
247 iowrite8(CR_DISABLE_TX, &channel->regs->w.cr);
248 /* In case of RS-485, change from TX to RX when finishing TX.
249 * Half-duplex. */
250 if (channel->board_id == IPACK1_DEVICE_ID_SBS_OCTAL_485) {
251 iowrite8(CR_CMD_NEGATE_RTSN, &channel->regs->w.cr);
252 iowrite8(CR_ENABLE_RX, &channel->regs->w.cr);
253 channel->rx_enable = 1;
254 }
255 }
256
257 /* RX data */
258 if ((isr & channel->isr_rx_rdy_mask) && (sr & SR_RX_READY))
259 ipoctal_irq_rx(channel, sr);
260
261 /* TX of each character */
262 if ((isr & channel->isr_tx_rdy_mask) && (sr & SR_TX_READY))
263 ipoctal_irq_tx(channel);
264}
265
266static irqreturn_t ipoctal_irq_handler(void *arg)
267{
268 unsigned int i;
269 struct ipoctal *ipoctal = arg;
270
271 /* Clear the IPack device interrupt */
272 readw(ipoctal->int_space + ACK_INT_REQ0);
273 readw(ipoctal->int_space + ACK_INT_REQ1);
274
275 /* Check all channels */
276 for (i = 0; i < NR_CHANNELS; i++)
277 ipoctal_irq_channel(&ipoctal->channel[i]);
278
279 return IRQ_HANDLED;
280}
281
282static const struct tty_port_operations ipoctal_tty_port_ops = {
283 .dtr_rts = NULL,
284 .activate = ipoctal_port_activate,
285};
286
287static int ipoctal_inst_slot(struct ipoctal *ipoctal, unsigned int bus_nr,
288 unsigned int slot)
289{
290 int res;
291 int i;
292 struct tty_driver *drv;
293 struct ipoctal_channel *channel;
294 struct ipack_region *region;
295 void __iomem *addr;
296 union scc2698_channel __iomem *chan_regs;
297 union scc2698_block __iomem *block_regs;
298
299 ipoctal->board_id = ipoctal->dev->id_device;
300
301 region = &ipoctal->dev->region[IPACK_IO_SPACE];
302 addr = devm_ioremap(&ipoctal->dev->dev,
303 region->start, region->size);
304 if (!addr) {
305 dev_err(&ipoctal->dev->dev,
306 "Unable to map slot [%d:%d] IO space!\n",
307 bus_nr, slot);
308 return -EADDRNOTAVAIL;
309 }
310 /* Save the virtual address to access the registers easily */
311 chan_regs =
312 (union scc2698_channel __iomem *) addr;
313 block_regs =
314 (union scc2698_block __iomem *) addr;
315
316 region = &ipoctal->dev->region[IPACK_INT_SPACE];
317 ipoctal->int_space =
318 devm_ioremap(&ipoctal->dev->dev,
319 region->start, region->size);
320 if (!ipoctal->int_space) {
321 dev_err(&ipoctal->dev->dev,
322 "Unable to map slot [%d:%d] INT space!\n",
323 bus_nr, slot);
324 return -EADDRNOTAVAIL;
325 }
326
327 region = &ipoctal->dev->region[IPACK_MEM8_SPACE];
328 ipoctal->mem8_space =
329 devm_ioremap(&ipoctal->dev->dev,
330 region->start, 0x8000);
331 if (!ipoctal->mem8_space) {
332 dev_err(&ipoctal->dev->dev,
333 "Unable to map slot [%d:%d] MEM8 space!\n",
334 bus_nr, slot);
335 return -EADDRNOTAVAIL;
336 }
337
338
339 /* Disable RX and TX before touching anything */
340 for (i = 0; i < NR_CHANNELS ; i++) {
341 struct ipoctal_channel *channel = &ipoctal->channel[i];
342 channel->regs = chan_regs + i;
343 channel->block_regs = block_regs + (i >> 1);
344 channel->board_id = ipoctal->board_id;
345 if (i & 1) {
346 channel->isr_tx_rdy_mask = ISR_TxRDY_B;
347 channel->isr_rx_rdy_mask = ISR_RxRDY_FFULL_B;
348 } else {
349 channel->isr_tx_rdy_mask = ISR_TxRDY_A;
350 channel->isr_rx_rdy_mask = ISR_RxRDY_FFULL_A;
351 }
352
353 ipoctal_reset_channel(channel);
354 iowrite8(MR1_CHRL_8_BITS | MR1_ERROR_CHAR | MR1_RxINT_RxRDY,
355 &channel->regs->w.mr); /* mr1 */
356 iowrite8(0, &channel->regs->w.mr); /* mr2 */
357 iowrite8(TX_CLK_9600 | RX_CLK_9600, &channel->regs->w.csr);
358 }
359
360 for (i = 0; i < IP_OCTAL_NB_BLOCKS; i++) {
361 iowrite8(ACR_BRG_SET2, &block_regs[i].w.acr);
362 iowrite8(OPCR_MPP_OUTPUT | OPCR_MPOa_RTSN | OPCR_MPOb_RTSN,
363 &block_regs[i].w.opcr);
364 iowrite8(IMR_TxRDY_A | IMR_RxRDY_FFULL_A | IMR_DELTA_BREAK_A |
365 IMR_TxRDY_B | IMR_RxRDY_FFULL_B | IMR_DELTA_BREAK_B,
366 &block_regs[i].w.imr);
367 }
368
369 /* Dummy write */
370 iowrite8(1, ipoctal->mem8_space + 1);
371
372 /* Register the TTY device */
373
374 /* Each IP-OCTAL channel is a TTY port */
375 drv = tty_alloc_driver(NR_CHANNELS, TTY_DRIVER_REAL_RAW |
376 TTY_DRIVER_DYNAMIC_DEV);
377 if (IS_ERR(drv))
378 return PTR_ERR(drv);
379
380 /* Fill struct tty_driver with ipoctal data */
381 drv->owner = THIS_MODULE;
382 drv->driver_name = KBUILD_MODNAME;
383 drv->name = kasprintf(GFP_KERNEL, KBUILD_MODNAME ".%d.%d.", bus_nr, slot);
384 if (!drv->name) {
385 res = -ENOMEM;
386 goto err_put_driver;
387 }
388 drv->major = 0;
389
390 drv->minor_start = 0;
391 drv->type = TTY_DRIVER_TYPE_SERIAL;
392 drv->subtype = SERIAL_TYPE_NORMAL;
393 drv->init_termios = tty_std_termios;
394 drv->init_termios.c_cflag = B9600 | CS8 | CREAD | HUPCL | CLOCAL;
395 drv->init_termios.c_ispeed = 9600;
396 drv->init_termios.c_ospeed = 9600;
397
398 tty_set_operations(drv, &ipoctal_fops);
399 res = tty_register_driver(drv);
400 if (res) {
401 dev_err(&ipoctal->dev->dev, "Can't register tty driver.\n");
402 goto err_free_name;
403 }
404
405 /* Save struct tty_driver for use it when uninstalling the device */
406 ipoctal->tty_drv = drv;
407
408 for (i = 0; i < NR_CHANNELS; i++) {
409 struct device *tty_dev;
410
411 channel = &ipoctal->channel[i];
412 tty_port_init(&channel->tty_port);
413 res = tty_port_alloc_xmit_buf(&channel->tty_port);
414 if (res)
415 continue;
416 channel->tty_port.ops = &ipoctal_tty_port_ops;
417
418 ipoctal_reset_stats(&channel->stats);
419 channel->nb_bytes = 0;
420 spin_lock_init(&channel->lock);
421 channel->pointer_read = 0;
422 channel->pointer_write = 0;
423 tty_dev = tty_port_register_device_attr(&channel->tty_port, drv,
424 i, NULL, channel, NULL);
425 if (IS_ERR(tty_dev)) {
426 dev_err(&ipoctal->dev->dev, "Failed to register tty device.\n");
427 tty_port_free_xmit_buf(&channel->tty_port);
428 tty_port_destroy(&channel->tty_port);
429 continue;
430 }
431 channel->tty_registered = true;
432 }
433
434 /*
435 * IP-OCTAL has different addresses to copy its IRQ vector.
436 * Depending of the carrier these addresses are accesible or not.
437 * More info in the datasheet.
438 */
439 ipoctal->dev->bus->ops->request_irq(ipoctal->dev,
440 ipoctal_irq_handler, ipoctal);
441
442 return 0;
443
444err_free_name:
445 kfree(drv->name);
446err_put_driver:
447 tty_driver_kref_put(drv);
448
449 return res;
450}
451
452static inline size_t ipoctal_copy_write_buffer(struct ipoctal_channel *channel,
453 const u8 *buf, size_t count)
454{
455 unsigned long flags;
456 size_t i;
457 unsigned int *pointer_read = &channel->pointer_read;
458
459 /* Copy the bytes from the user buffer to the internal one */
460 for (i = 0; i < count; i++) {
461 if (i <= (PAGE_SIZE - channel->nb_bytes)) {
462 spin_lock_irqsave(&channel->lock, flags);
463 channel->tty_port.xmit_buf[*pointer_read] = buf[i];
464 *pointer_read = (*pointer_read + 1) % PAGE_SIZE;
465 channel->nb_bytes++;
466 spin_unlock_irqrestore(&channel->lock, flags);
467 } else {
468 break;
469 }
470 }
471 return i;
472}
473
474static ssize_t ipoctal_write_tty(struct tty_struct *tty, const u8 *buf,
475 size_t count)
476{
477 struct ipoctal_channel *channel = tty->driver_data;
478 struct ipoctal *ipoctal = chan_to_ipoctal(channel, tty->index);
479 size_t char_copied;
480
481 guard(rwsem_read)(&ipoctal->remove_sem);
482 if (ipoctal->removed || !channel->tty_port.xmit_buf)
483 return 0;
484
485 char_copied = ipoctal_copy_write_buffer(channel, buf, count);
486
487 /* As the IP-OCTAL 485 only supports half duplex, do it manually */
488 if (channel->board_id == IPACK1_DEVICE_ID_SBS_OCTAL_485) {
489 iowrite8(CR_DISABLE_RX, &channel->regs->w.cr);
490 channel->rx_enable = 0;
491 iowrite8(CR_CMD_ASSERT_RTSN, &channel->regs->w.cr);
492 }
493
494 /*
495 * Send a packet and then disable TX to avoid failure after several send
496 * operations
497 */
498 iowrite8(CR_ENABLE_TX, &channel->regs->w.cr);
499 return char_copied;
500}
501
502static unsigned int ipoctal_write_room(struct tty_struct *tty)
503{
504 struct ipoctal_channel *channel = tty->driver_data;
505
506 return PAGE_SIZE - channel->nb_bytes;
507}
508
509static unsigned int ipoctal_chars_in_buffer(struct tty_struct *tty)
510{
511 struct ipoctal_channel *channel = tty->driver_data;
512
513 return channel->nb_bytes;
514}
515
516static void ipoctal_set_termios(struct tty_struct *tty,
517 const struct ktermios *old_termios)
518{
519 unsigned int cflag;
520 unsigned char mr1 = 0;
521 unsigned char mr2 = 0;
522 unsigned char csr = 0;
523 struct ipoctal_channel *channel = tty->driver_data;
524 struct ipoctal *ipoctal = chan_to_ipoctal(channel, tty->index);
525 speed_t baud;
526
527 guard(rwsem_read)(&ipoctal->remove_sem);
528 if (ipoctal->removed)
529 return;
530
531 cflag = tty->termios.c_cflag;
532
533 /* Disable and reset everything before change the setup */
534 ipoctal_reset_channel(channel);
535
536 /* Set Bits per chars */
537 switch (cflag & CSIZE) {
538 case CS6:
539 mr1 |= MR1_CHRL_6_BITS;
540 break;
541 case CS7:
542 mr1 |= MR1_CHRL_7_BITS;
543 break;
544 case CS8:
545 default:
546 mr1 |= MR1_CHRL_8_BITS;
547 /* By default, select CS8 */
548 tty->termios.c_cflag = (cflag & ~CSIZE) | CS8;
549 break;
550 }
551
552 /* Set Parity */
553 if (cflag & PARENB)
554 if (cflag & PARODD)
555 mr1 |= MR1_PARITY_ON | MR1_PARITY_ODD;
556 else
557 mr1 |= MR1_PARITY_ON | MR1_PARITY_EVEN;
558 else
559 mr1 |= MR1_PARITY_OFF;
560
561 /* Mark or space parity is not supported */
562 tty->termios.c_cflag &= ~CMSPAR;
563
564 /* Set stop bits */
565 if (cflag & CSTOPB)
566 mr2 |= MR2_STOP_BITS_LENGTH_2;
567 else
568 mr2 |= MR2_STOP_BITS_LENGTH_1;
569
570 /* Set the flow control */
571 switch (channel->board_id) {
572 case IPACK1_DEVICE_ID_SBS_OCTAL_232:
573 if (cflag & CRTSCTS) {
574 mr1 |= MR1_RxRTS_CONTROL_ON;
575 mr2 |= MR2_TxRTS_CONTROL_OFF | MR2_CTS_ENABLE_TX_ON;
576 } else {
577 mr1 |= MR1_RxRTS_CONTROL_OFF;
578 mr2 |= MR2_TxRTS_CONTROL_OFF | MR2_CTS_ENABLE_TX_OFF;
579 }
580 break;
581 case IPACK1_DEVICE_ID_SBS_OCTAL_422:
582 mr1 |= MR1_RxRTS_CONTROL_OFF;
583 mr2 |= MR2_TxRTS_CONTROL_OFF | MR2_CTS_ENABLE_TX_OFF;
584 break;
585 case IPACK1_DEVICE_ID_SBS_OCTAL_485:
586 mr1 |= MR1_RxRTS_CONTROL_OFF;
587 mr2 |= MR2_TxRTS_CONTROL_ON | MR2_CTS_ENABLE_TX_OFF;
588 break;
589 default:
590 return;
591 }
592
593 baud = tty_get_baud_rate(tty);
594 tty_termios_encode_baud_rate(&tty->termios, baud, baud);
595
596 /* Set baud rate */
597 switch (baud) {
598 case 75:
599 csr |= TX_CLK_75 | RX_CLK_75;
600 break;
601 case 110:
602 csr |= TX_CLK_110 | RX_CLK_110;
603 break;
604 case 150:
605 csr |= TX_CLK_150 | RX_CLK_150;
606 break;
607 case 300:
608 csr |= TX_CLK_300 | RX_CLK_300;
609 break;
610 case 600:
611 csr |= TX_CLK_600 | RX_CLK_600;
612 break;
613 case 1200:
614 csr |= TX_CLK_1200 | RX_CLK_1200;
615 break;
616 case 1800:
617 csr |= TX_CLK_1800 | RX_CLK_1800;
618 break;
619 case 2000:
620 csr |= TX_CLK_2000 | RX_CLK_2000;
621 break;
622 case 2400:
623 csr |= TX_CLK_2400 | RX_CLK_2400;
624 break;
625 case 4800:
626 csr |= TX_CLK_4800 | RX_CLK_4800;
627 break;
628 case 9600:
629 csr |= TX_CLK_9600 | RX_CLK_9600;
630 break;
631 case 19200:
632 csr |= TX_CLK_19200 | RX_CLK_19200;
633 break;
634 case 38400:
635 default:
636 csr |= TX_CLK_38400 | RX_CLK_38400;
637 /* In case of default, we establish 38400 bps */
638 tty_termios_encode_baud_rate(&tty->termios, 38400, 38400);
639 break;
640 }
641
642 mr1 |= MR1_ERROR_CHAR;
643 mr1 |= MR1_RxINT_RxRDY;
644
645 /* Write the control registers */
646 iowrite8(mr1, &channel->regs->w.mr);
647 iowrite8(mr2, &channel->regs->w.mr);
648 iowrite8(csr, &channel->regs->w.csr);
649
650 /* Enable again the RX, if it was before */
651 if (channel->rx_enable)
652 iowrite8(CR_ENABLE_RX, &channel->regs->w.cr);
653}
654
655static void ipoctal_hangup(struct tty_struct *tty)
656{
657 unsigned long flags;
658 struct ipoctal_channel *channel = tty->driver_data;
659 struct ipoctal *ipoctal;
660
661 if (channel == NULL)
662 return;
663
664 ipoctal = chan_to_ipoctal(channel, tty->index);
665 guard(rwsem_read)(&ipoctal->remove_sem);
666 if (ipoctal->removed)
667 return;
668
669 spin_lock_irqsave(&channel->lock, flags);
670 channel->nb_bytes = 0;
671 channel->pointer_read = 0;
672 channel->pointer_write = 0;
673 spin_unlock_irqrestore(&channel->lock, flags);
674
675 tty_port_hangup(&channel->tty_port);
676
677 ipoctal_reset_channel(channel);
678 tty_port_set_initialized(&channel->tty_port, false);
679 wake_up_interruptible(&channel->tty_port.open_wait);
680}
681
682static void ipoctal_shutdown(struct tty_struct *tty)
683{
684 struct ipoctal_channel *channel = tty->driver_data;
685 struct ipoctal *ipoctal;
686
687 if (channel == NULL)
688 return;
689
690 ipoctal = chan_to_ipoctal(channel, tty->index);
691 guard(rwsem_read)(&ipoctal->remove_sem);
692 if (ipoctal->removed)
693 return;
694
695 ipoctal_reset_channel(channel);
696 tty_port_set_initialized(&channel->tty_port, false);
697}
698
699static void ipoctal_cleanup(struct tty_struct *tty)
700{
701 struct ipoctal_channel *channel = tty->driver_data;
702 struct ipoctal *ipoctal = chan_to_ipoctal(channel, tty->index);
703
704 /* release the carrier driver via cached owner */
705 module_put(ipoctal->carrier_owner);
706 kref_put(&ipoctal->kref, ipoctal_release);
707}
708
709static const struct tty_operations ipoctal_fops = {
710 .ioctl = NULL,
711 .install = ipoctal_install,
712 .open = ipoctal_open,
713 .close = ipoctal_close,
714 .write = ipoctal_write_tty,
715 .set_termios = ipoctal_set_termios,
716 .write_room = ipoctal_write_room,
717 .chars_in_buffer = ipoctal_chars_in_buffer,
718 .get_icount = ipoctal_get_icount,
719 .hangup = ipoctal_hangup,
720 .shutdown = ipoctal_shutdown,
721 .cleanup = ipoctal_cleanup,
722};
723
724static void ipoctal_release(struct kref *kref)
725{
726 struct ipoctal *ipoctal = container_of(kref, struct ipoctal, kref);
727
728 kfree(ipoctal);
729}
730
731static int ipoctal_probe(struct ipack_device *dev)
732{
733 int res;
734 struct ipoctal *ipoctal;
735
736 ipoctal = kzalloc_obj(struct ipoctal);
737 if (ipoctal == NULL)
738 return -ENOMEM;
739
740 kref_init(&ipoctal->kref);
741 init_rwsem(&ipoctal->remove_sem);
742
743 ipoctal->dev = dev;
744 ipoctal->carrier_owner = dev->bus->owner;
745 res = ipoctal_inst_slot(ipoctal, dev->bus->bus_nr, dev->slot);
746 if (res)
747 goto out_uninst;
748
749 dev_set_drvdata(&dev->dev, ipoctal);
750 return 0;
751
752out_uninst:
753 kref_put(&ipoctal->kref, ipoctal_release);
754 return res;
755}
756
757static void __ipoctal_remove(struct ipoctal *ipoctal)
758{
759 int i;
760
761 scoped_guard(rwsem_write, &ipoctal->remove_sem)
762 ipoctal->removed = true;
763
764 ipoctal->dev->bus->ops->free_irq(ipoctal->dev);
765
766 for (i = 0; i < NR_CHANNELS; i++) {
767 struct ipoctal_channel *channel = &ipoctal->channel[i];
768
769 if (!channel->tty_registered)
770 continue;
771
772 tty_unregister_device(ipoctal->tty_drv, i);
773 tty_port_free_xmit_buf(&channel->tty_port);
774 tty_port_destroy(&channel->tty_port);
775 }
776
777 tty_unregister_driver(ipoctal->tty_drv);
778 kfree(ipoctal->tty_drv->name);
779 tty_driver_kref_put(ipoctal->tty_drv);
780 kref_put(&ipoctal->kref, ipoctal_release);
781}
782
783static void ipoctal_remove(struct ipack_device *idev)
784{
785 __ipoctal_remove(dev_get_drvdata(&idev->dev));
786}
787
788static DEFINE_IPACK_DEVICE_TABLE(ipoctal_ids) = {
789 { IPACK_DEVICE(IPACK_ID_VERSION_1, IPACK1_VENDOR_ID_SBS,
790 IPACK1_DEVICE_ID_SBS_OCTAL_232) },
791 { IPACK_DEVICE(IPACK_ID_VERSION_1, IPACK1_VENDOR_ID_SBS,
792 IPACK1_DEVICE_ID_SBS_OCTAL_422) },
793 { IPACK_DEVICE(IPACK_ID_VERSION_1, IPACK1_VENDOR_ID_SBS,
794 IPACK1_DEVICE_ID_SBS_OCTAL_485) },
795 { 0, },
796};
797
798MODULE_DEVICE_TABLE(ipack, ipoctal_ids);
799
800static const struct ipack_driver_ops ipoctal_drv_ops = {
801 .probe = ipoctal_probe,
802 .remove = ipoctal_remove,
803};
804
805static struct ipack_driver driver = {
806 .ops = &ipoctal_drv_ops,
807 .id_table = ipoctal_ids,
808};
809
810static int __init ipoctal_init(void)
811{
812 return ipack_driver_register(&driver, THIS_MODULE, KBUILD_MODNAME);
813}
814
815static void __exit ipoctal_exit(void)
816{
817 ipack_driver_unregister(&driver);
818}
819
820MODULE_DESCRIPTION("IP-Octal 232, 422 and 485 device driver");
821MODULE_LICENSE("GPL");
822
823module_init(ipoctal_init);
824module_exit(ipoctal_exit);