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