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