drivers/ipack/devices/ipoctal.c

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