drivers/net/irda/irport.c

   1 /*********************************************************************
   2  *
   3  * Filename:      irport.c
   4  * Version:       1.0
   5  * Description:   Half duplex serial port SIR driver for IrDA.
   6  * Status:        Experimental.
   7  * Author:        Dag Brattli <dagb@cs.uit.no>
   8  * Created at:    Sun Aug  3 13:49:59 1997
   9  * Modified at:   Fri Jan 28 20:22:38 2000
  10  * Modified by:   Dag Brattli <dagb@cs.uit.no>
  11  * Sources:       serial.c by Linus Torvalds
  12  *
  13  *     Copyright (c) 1997, 1998, 1999-2000 Dag Brattli, All Rights Reserved.
  14  *     Copyright (c) 2000-2003 Jean Tourrilhes, All Rights Reserved.
  15  *
  16  *     This program is free software; you can redistribute it and/or
  17  *     modify it under the terms of the GNU General Public License as
  18  *     published by the Free Software Foundation; either version 2 of
  19  *     the License, or (at your option) any later version.
  20  *
  21  *     This program is distributed in the hope that it will be useful,
  22  *     but WITHOUT ANY WARRANTY; without even the implied warranty of
  23  *     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  24  *     GNU General Public License for more details.
  25  *
  26  *     You should have received a copy of the GNU General Public License
  27  *     along with this program; if not, write to the Free Software
  28  *     Foundation, Inc., 59 Temple Place, Suite 330, Boston,
  29  *     MA 02111-1307 USA
  30  *
  31  *     This driver is ment to be a small half duplex serial driver to be
  32  *     used for IR-chipsets that has a UART (16550) compatibility mode.
  33  *     Eventually it will replace irtty, because of irtty has some
  34  *     problems that is hard to get around when we don't have control
  35  *     over the serial driver. This driver may also be used by FIR
  36  *     drivers to handle SIR mode for them.
  37  *
  38  ********************************************************************/
  39
  40 #include <linux/module.h>
  41
  42 #include <linux/kernel.h>
  43 #include <linux/types.h>
  44 #include <linux/ioport.h>
  45 #include <linux/slab.h>
  46 #include <linux/string.h>
  47 #include <linux/skbuff.h>
  48 #include <linux/serial_reg.h>
  49 #include <linux/errno.h>
  50 #include <linux/init.h>
  51 #include <linux/spinlock.h>
  52 #include <linux/delay.h>
  53 #include <linux/rtnetlink.h>
  54 #include <linux/bitops.h>
  55
  56 #include <asm/system.h>
  57 #include <asm/io.h>
  58
  59 #include <net/irda/irda.h>
  60 #include <net/irda/wrapper.h>
  61 #include "irport.h"
  62
  63 #define IO_EXTENT 8
  64
  65 /*
  66  * Currently you'll need to set these values using insmod like this:
  67  * insmod irport io=0x3e8 irq=11
  68  */
  69 static unsigned int io[]  = { ~0, ~0, ~0, ~0 };
  70 static unsigned int irq[] = { 0, 0, 0, 0 };
  71
  72 static unsigned int qos_mtt_bits = 0x03;
  73
  74 static struct irport_cb *dev_self[] = { NULL, NULL, NULL, NULL};
  75 static char *driver_name = "irport";
  76
  77 static inline void irport_write_wakeup(struct irport_cb *self);
  78 static inline int  irport_write(int iobase, int fifo_size, __u8 *buf, int len);
  79 static inline void irport_receive(struct irport_cb *self);
  80
  81 static int  irport_net_ioctl(struct net_device *dev, struct ifreq *rq,
  82                              int cmd);
  83 static inline int  irport_is_receiving(struct irport_cb *self);
  84 static int  irport_set_dtr_rts(struct net_device *dev, int dtr, int rts);
  85 static int  irport_raw_write(struct net_device *dev, __u8 *buf, int len);
  86 static struct net_device_stats *irport_net_get_stats(struct net_device *dev);
  87 static int irport_change_speed_complete(struct irda_task *task);
  88 static void irport_timeout(struct net_device *dev);
  89
  90 static irqreturn_t irport_interrupt(int irq, void *dev_id,
  91                                     struct pt_regs *regs);
  92 static int irport_hard_xmit(struct sk_buff *skb, struct net_device *dev);
  93 static void irport_change_speed(void *priv, __u32 speed);
  94 static int irport_net_open(struct net_device *dev);
  95 static int irport_net_close(struct net_device *dev);
  96
  97 static struct irport_cb *
  98 irport_open(int i, unsigned int iobase, unsigned int irq)
  99 {
 100         struct net_device *dev;
 101         struct irport_cb *self;
 102
 103         IRDA_DEBUG(1, "%s()\n", __FUNCTION__);
 104
 105         /* Lock the port that we need */
 106         if (!request_region(iobase, IO_EXTENT, driver_name)) {
 107                 IRDA_DEBUG(0, "%s(), can't get iobase of 0x%03x\n",
 108                            __FUNCTION__, iobase);
 109                 goto err_out1;
 110         }
 111
 112         /*
 113          *  Allocate new instance of the driver
 114          */
 115         dev = alloc_irdadev(sizeof(struct irport_cb));
 116         if (!dev) {
 117                 IRDA_ERROR("%s(), can't allocate memory for "
 118                            "irda device!\n", __FUNCTION__);
 119                 goto err_out2;
 120         }
 121
 122         self = dev->priv;
 123         spin_lock_init(&self->lock);
 124
 125         /* Need to store self somewhere */
 126         dev_self[i] = self;
 127         self->priv = self;
 128         self->index = i;
 129
 130         /* Initialize IO */
 131         self->io.sir_base  = iobase;
 132         self->io.sir_ext   = IO_EXTENT;
 133         self->io.irq       = irq;
 134         self->io.fifo_size = 16;                /* 16550A and compatible */
 135
 136         /* Initialize QoS for this device */
 137         irda_init_max_qos_capabilies(&self->qos);
 138
 139         self->qos.baud_rate.bits = IR_9600|IR_19200|IR_38400|IR_57600|
 140                 IR_115200;
 141
 142         self->qos.min_turn_time.bits = qos_mtt_bits;
 143         irda_qos_bits_to_value(&self->qos);
 144
 145         /* Bootstrap ZeroCopy Rx */
 146         self->rx_buff.truesize = IRDA_SKB_MAX_MTU;
 147         self->rx_buff.skb = __dev_alloc_skb(self->rx_buff.truesize,
 148                                             GFP_KERNEL);
 149         if (self->rx_buff.skb == NULL) {
 150                 IRDA_ERROR("%s(), can't allocate memory for "
 151                            "receive buffer!\n", __FUNCTION__);
 152                 goto err_out3;
 153         }
 154         skb_reserve(self->rx_buff.skb, 1);
 155         self->rx_buff.head = self->rx_buff.skb->data;
 156         /* No need to memset the buffer, unless you are really pedantic */
 157
 158         /* Finish setup the Rx buffer descriptor */
 159         self->rx_buff.in_frame = FALSE;
 160         self->rx_buff.state = OUTSIDE_FRAME;
 161         self->rx_buff.data = self->rx_buff.head;
 162
 163         /* Specify how much memory we want */
 164         self->tx_buff.truesize = 4000;
 165
 166         /* Allocate memory if needed */
 167         if (self->tx_buff.truesize > 0) {
 168                 self->tx_buff.head = (__u8 *) kmalloc(self->tx_buff.truesize,
 169                                                       GFP_KERNEL);
 170                 if (self->tx_buff.head == NULL) {
 171                         IRDA_ERROR("%s(), can't allocate memory for "
 172                                    "transmit buffer!\n", __FUNCTION__);
 173                         goto err_out4;
 174                 }
 175                 memset(self->tx_buff.head, 0, self->tx_buff.truesize);
 176         }
 177         self->tx_buff.data = self->tx_buff.head;
 178
 179         self->netdev = dev;
 180         /* Keep track of module usage */
 181         SET_MODULE_OWNER(dev);
 182
 183         /* May be overridden by piggyback drivers */
 184         self->interrupt    = irport_interrupt;
 185         self->change_speed = irport_change_speed;
 186
 187         /* Override the network functions we need to use */
 188         dev->hard_start_xmit = irport_hard_xmit;
 189         dev->tx_timeout      = irport_timeout;
 190         dev->watchdog_timeo  = HZ;  /* Allow time enough for speed change */
 191         dev->open            = irport_net_open;
 192         dev->stop            = irport_net_close;
 193         dev->get_stats       = irport_net_get_stats;
 194         dev->do_ioctl        = irport_net_ioctl;
 195
 196         /* Make ifconfig display some details */
 197         dev->base_addr = iobase;
 198         dev->irq = irq;
 199
 200         if (register_netdev(dev)) {
 201                 IRDA_ERROR("%s(), register_netdev() failed!\n", __FUNCTION__);
 202                 goto err_out5;
 203         }
 204         IRDA_MESSAGE("IrDA: Registered device %s (irport io=0x%X irq=%d)\n",
 205                 dev->name, iobase, irq);
 206
 207         return self;
 208  err_out5:
 209         kfree(self->tx_buff.head);
 210  err_out4:
 211         kfree_skb(self->rx_buff.skb);
 212  err_out3:
 213         free_netdev(dev);
 214         dev_self[i] = NULL;
 215  err_out2:
 216         release_region(iobase, IO_EXTENT);
 217  err_out1:
 218         return NULL;
 219 }
 220
 221 static int irport_close(struct irport_cb *self)
 222 {
 223         IRDA_ASSERT(self != NULL, return -1;);
 224
 225         /* We are not using any dongle anymore! */
 226         if (self->dongle)
 227                 irda_device_dongle_cleanup(self->dongle);
 228         self->dongle = NULL;
 229
 230         /* Remove netdevice */
 231         unregister_netdev(self->netdev);
 232
 233         /* Release the IO-port that this driver is using */
 234         IRDA_DEBUG(0 , "%s(), Releasing Region %03x\n",
 235                    __FUNCTION__, self->io.sir_base);
 236         release_region(self->io.sir_base, self->io.sir_ext);
 237
 238         kfree(self->tx_buff.head);
 239
 240         if (self->rx_buff.skb)
 241                 kfree_skb(self->rx_buff.skb);
 242         self->rx_buff.skb = NULL;
 243
 244         /* Remove ourselves */
 245         dev_self[self->index] = NULL;
 246         free_netdev(self->netdev);
 247
 248         return 0;
 249 }
 250
 251 static void irport_stop(struct irport_cb *self)
 252 {
 253         int iobase;
 254
 255         iobase = self->io.sir_base;
 256
 257         /* We can't lock, we may be called from a FIR driver - Jean II */
 258
 259         /* We are not transmitting any more */
 260         self->transmitting = 0;
 261
 262         /* Reset UART */
 263         outb(0, iobase+UART_MCR);
 264
 265         /* Turn off interrupts */
 266         outb(0, iobase+UART_IER);
 267 }
 268
 269 static void irport_start(struct irport_cb *self)
 270 {
 271         int iobase;
 272
 273         iobase = self->io.sir_base;
 274
 275         irport_stop(self);
 276
 277         /* We can't lock, we may be called from a FIR driver - Jean II */
 278
 279         /* Initialize UART */
 280         outb(UART_LCR_WLEN8, iobase+UART_LCR);  /* Reset DLAB */
 281         outb((UART_MCR_DTR | UART_MCR_RTS | UART_MCR_OUT2), iobase+UART_MCR);
 282
 283         /* Turn on interrups */
 284         outb(UART_IER_RLSI | UART_IER_RDI |UART_IER_THRI, iobase+UART_IER);
 285 }
 286
 287 /*
 288  * Function irport_probe (void)
 289  *
 290  *    Start IO port
 291  *
 292  */
 293 int irport_probe(int iobase)
 294 {
 295         IRDA_DEBUG(4, "%s(), iobase=%#x\n", __FUNCTION__, iobase);
 296
 297         return 0;
 298 }
 299
 300 /*
 301  * Function irport_get_fcr (speed)
 302  *
 303  *    Compute value of fcr
 304  *
 305  */
 306 static inline unsigned int irport_get_fcr(__u32 speed)
 307 {
 308         unsigned int fcr;    /* FIFO control reg */
 309
 310         /* Enable fifos */
 311         fcr = UART_FCR_ENABLE_FIFO;
 312
 313         /*
 314          * Use trigger level 1 to avoid 3 ms. timeout delay at 9600 bps, and
 315          * almost 1,7 ms at 19200 bps. At speeds above that we can just forget
 316          * about this timeout since it will always be fast enough.
 317          */
 318         if (speed < 38400)
 319                 fcr |= UART_FCR_TRIGGER_1;
 320         else
 321                 //fcr |= UART_FCR_TRIGGER_14;
 322                 fcr |= UART_FCR_TRIGGER_8;
 323
 324         return(fcr);
 325 }
 326
 327 /*
 328  * Function irport_change_speed (self, speed)
 329  *
 330  *    Set speed of IrDA port to specified baudrate
 331  *
 332  * This function should be called with irq off and spin-lock.
 333  */
 334 static void irport_change_speed(void *priv, __u32 speed)
 335 {
 336         struct irport_cb *self = (struct irport_cb *) priv;
 337         int iobase;
 338         unsigned int fcr;    /* FIFO control reg */
 339         unsigned int lcr;    /* Line control reg */
 340         int divisor;
 341
 342         IRDA_ASSERT(self != NULL, return;);
 343         IRDA_ASSERT(speed != 0, return;);
 344
 345         IRDA_DEBUG(1, "%s(), Setting speed to: %d - iobase=%#x\n",
 346                     __FUNCTION__, speed, self->io.sir_base);
 347
 348         /* We can't lock, we may be called from a FIR driver - Jean II */
 349
 350         iobase = self->io.sir_base;
 351
 352         /* Update accounting for new speed */
 353         self->io.speed = speed;
 354
 355         /* Turn off interrupts */
 356         outb(0, iobase+UART_IER);
 357
 358         divisor = SPEED_MAX/speed;
 359
 360         /* Get proper fifo configuration */
 361         fcr = irport_get_fcr(speed);
 362
 363         /* IrDA ports use 8N1 */
 364         lcr = UART_LCR_WLEN8;
 365
 366         outb(UART_LCR_DLAB | lcr, iobase+UART_LCR); /* Set DLAB */
 367         outb(divisor & 0xff,      iobase+UART_DLL); /* Set speed */
 368         outb(divisor >> 8,        iobase+UART_DLM);
 369         outb(lcr,                 iobase+UART_LCR); /* Set 8N1  */
 370         outb(fcr,                 iobase+UART_FCR); /* Enable FIFO's */
 371
 372         /* Turn on interrups */
 373         /* This will generate a fatal interrupt storm.
 374          * People calling us will do that properly - Jean II */
 375         //outb(/*UART_IER_RLSI|*/UART_IER_RDI/*|UART_IER_THRI*/, iobase+UART_IER);
 376 }
 377
 378 /*
 379  * Function __irport_change_speed (instance, state, param)
 380  *
 381  *    State machine for changing speed of the device. We do it this way since
 382  *    we cannot use schedule_timeout() when we are in interrupt context
 383  *
 384  */
 385 int __irport_change_speed(struct irda_task *task)
 386 {
 387         struct irport_cb *self;
 388         __u32 speed = (__u32) task->param;
 389         unsigned long flags = 0;
 390         int wasunlocked = 0;
 391         int ret = 0;
 392
 393         IRDA_DEBUG(2, "%s(), <%ld>\n", __FUNCTION__, jiffies);
 394
 395         self = (struct irport_cb *) task->instance;
 396
 397         IRDA_ASSERT(self != NULL, return -1;);
 398
 399         /* Locking notes : this function may be called from irq context with
 400          * spinlock, via irport_write_wakeup(), or from non-interrupt without
 401          * spinlock (from the task timer). Yuck !
 402          * This is ugly, and unsafe is the spinlock is not already aquired.
 403          * This will be fixed when irda-task get rewritten.
 404          * Jean II */
 405         if (!spin_is_locked(&self->lock)) {
 406                 spin_lock_irqsave(&self->lock, flags);
 407                 wasunlocked = 1;
 408         }
 409
 410         switch (task->state) {
 411         case IRDA_TASK_INIT:
 412         case IRDA_TASK_WAIT:
 413                 /* Are we ready to change speed yet? */
 414                 if (self->tx_buff.len > 0) {
 415                         task->state = IRDA_TASK_WAIT;
 416
 417                         /* Try again later */
 418                         ret = msecs_to_jiffies(20);
 419                         break;
 420                 }
 421
 422                 if (self->dongle)
 423                         irda_task_next_state(task, IRDA_TASK_CHILD_INIT);
 424                 else
 425                         irda_task_next_state(task, IRDA_TASK_CHILD_DONE);
 426                 break;
 427         case IRDA_TASK_CHILD_INIT:
 428                 /* Go to default speed */
 429                 self->change_speed(self->priv, 9600);
 430
 431                 /* Change speed of dongle */
 432                 if (irda_task_execute(self->dongle,
 433                                       self->dongle->issue->change_speed,
 434                                       NULL, task, (void *) speed))
 435                 {
 436                         /* Dongle need more time to change its speed */
 437                         irda_task_next_state(task, IRDA_TASK_CHILD_WAIT);
 438
 439                         /* Give dongle 1 sec to finish */
 440                         ret = msecs_to_jiffies(1000);
 441                 } else
 442                         /* Child finished immediately */
 443                         irda_task_next_state(task, IRDA_TASK_CHILD_DONE);
 444                 break;
 445         case IRDA_TASK_CHILD_WAIT:
 446                 IRDA_WARNING("%s(), changing speed of dongle timed out!\n", __FUNCTION__);
 447                 ret = -1;
 448                 break;
 449         case IRDA_TASK_CHILD_DONE:
 450                 /* Finally we are ready to change the speed */
 451                 self->change_speed(self->priv, speed);
 452
 453                 irda_task_next_state(task, IRDA_TASK_DONE);
 454                 break;
 455         default:
 456                 IRDA_ERROR("%s(), unknown state %d\n",
 457                            __FUNCTION__, task->state);
 458                 irda_task_next_state(task, IRDA_TASK_DONE);
 459                 ret = -1;
 460                 break;
 461         }
 462         /* Put stuff in the state we found them - Jean II */
 463         if(wasunlocked) {
 464                 spin_unlock_irqrestore(&self->lock, flags);
 465         }
 466
 467         return ret;
 468 }
 469
 470 /*
 471  * Function irport_change_speed_complete (task)
 472  *
 473  *    Called when the change speed operation completes
 474  *
 475  */
 476 static int irport_change_speed_complete(struct irda_task *task)
 477 {
 478         struct irport_cb *self;
 479
 480         IRDA_DEBUG(1, "%s()\n", __FUNCTION__);
 481
 482         self = (struct irport_cb *) task->instance;
 483
 484         IRDA_ASSERT(self != NULL, return -1;);
 485         IRDA_ASSERT(self->netdev != NULL, return -1;);
 486
 487         /* Finished changing speed, so we are not busy any longer */
 488         /* Signal network layer so it can try to send the frame */
 489
 490         netif_wake_queue(self->netdev);
 491
 492         return 0;
 493 }
 494
 495 /*
 496  * Function irport_timeout (struct net_device *dev)
 497  *
 498  *    The networking layer thinks we timed out.
 499  *
 500  */
 501
 502 static void irport_timeout(struct net_device *dev)
 503 {
 504         struct irport_cb *self;
 505         int iobase;
 506         int iir, lsr;
 507         unsigned long flags;
 508
 509         self = (struct irport_cb *) dev->priv;
 510         IRDA_ASSERT(self != NULL, return;);
 511         iobase = self->io.sir_base;
 512
 513         IRDA_WARNING("%s: transmit timed out, jiffies = %ld, trans_start = %ld\n",
 514                 dev->name, jiffies, dev->trans_start);
 515         spin_lock_irqsave(&self->lock, flags);
 516
 517         /* Debug what's happening... */
 518
 519         /* Get interrupt status */
 520         lsr = inb(iobase+UART_LSR);
 521         /* Read interrupt register */
 522         iir = inb(iobase+UART_IIR);
 523         IRDA_DEBUG(0, "%s(), iir=%02x, lsr=%02x, iobase=%#x\n",
 524                    __FUNCTION__, iir, lsr, iobase);
 525
 526         IRDA_DEBUG(0, "%s(), transmitting=%d, remain=%d, done=%d\n",
 527                    __FUNCTION__, self->transmitting, self->tx_buff.len,
 528                    self->tx_buff.data - self->tx_buff.head);
 529
 530         /* Now, restart the port */
 531         irport_start(self);
 532         self->change_speed(self->priv, self->io.speed);
 533         /* This will re-enable irqs */
 534         outb(/*UART_IER_RLSI|*/UART_IER_RDI/*|UART_IER_THRI*/, iobase+UART_IER);
 535         dev->trans_start = jiffies;
 536         spin_unlock_irqrestore(&self->lock, flags);
 537
 538         netif_wake_queue(dev);
 539 }
 540
 541 /*
 542  * Function irport_wait_hw_transmitter_finish ()
 543  *
 544  *    Wait for the real end of HW transmission
 545  *
 546  * The UART is a strict FIFO, and we get called only when we have finished
 547  * pushing data to the FIFO, so the maximum amount of time we must wait
 548  * is only for the FIFO to drain out.
 549  *
 550  * We use a simple calibrated loop. We may need to adjust the loop
 551  * delay (udelay) to balance I/O traffic and latency. And we also need to
 552  * adjust the maximum timeout.
 553  * It would probably be better to wait for the proper interrupt,
 554  * but it doesn't seem to be available.
 555  *
 556  * We can't use jiffies or kernel timers because :
 557  * 1) We are called from the interrupt handler, which disable softirqs,
 558  * so jiffies won't be increased
 559  * 2) Jiffies granularity is usually very coarse (10ms), and we don't
 560  * want to wait that long to detect stuck hardware.
 561  * Jean II
 562  */
 563
 564 static void irport_wait_hw_transmitter_finish(struct irport_cb *self)
 565 {
 566         int iobase;
 567         int count = 1000;       /* 1 ms */
 568
 569         iobase = self->io.sir_base;
 570
 571         /* Calibrated busy loop */
 572         while((count-- > 0) && !(inb(iobase+UART_LSR) & UART_LSR_TEMT))
 573                 udelay(1);
 574
 575         if(count == 0)
 576                 IRDA_DEBUG(0, "%s(): stuck transmitter\n", __FUNCTION__);
 577 }
 578
 579 /*
 580  * Function irport_hard_start_xmit (struct sk_buff *skb, struct net_device *dev)
 581  *
 582  *    Transmits the current frame until FIFO is full, then
 583  *    waits until the next transmitt interrupt, and continues until the
 584  *    frame is transmitted.
 585  */
 586 static int irport_hard_xmit(struct sk_buff *skb, struct net_device *dev)
 587 {
 588         struct irport_cb *self;
 589         unsigned long flags;
 590         int iobase;
 591         s32 speed;
 592
 593         IRDA_DEBUG(1, "%s()\n", __FUNCTION__);
 594
 595         IRDA_ASSERT(dev != NULL, return 0;);
 596
 597         self = (struct irport_cb *) dev->priv;
 598         IRDA_ASSERT(self != NULL, return 0;);
 599
 600         iobase = self->io.sir_base;
 601
 602         netif_stop_queue(dev);
 603
 604         /* Make sure tests & speed change are atomic */
 605         spin_lock_irqsave(&self->lock, flags);
 606
 607         /* Check if we need to change the speed */
 608         speed = irda_get_next_speed(skb);
 609         if ((speed != self->io.speed) && (speed != -1)) {
 610                 /* Check for empty frame */
 611                 if (!skb->len) {
 612                         /*
 613                          * We send frames one by one in SIR mode (no
 614                          * pipelining), so at this point, if we were sending
 615                          * a previous frame, we just received the interrupt
 616                          * telling us it is finished (UART_IIR_THRI).
 617                          * Therefore, waiting for the transmitter to really
 618                          * finish draining the fifo won't take too long.
 619                          * And the interrupt handler is not expected to run.
 620                          * - Jean II */
 621                         irport_wait_hw_transmitter_finish(self);
 622                         /* Better go there already locked - Jean II */
 623                         irda_task_execute(self, __irport_change_speed,
 624                                           irport_change_speed_complete,
 625                                           NULL, (void *) speed);
 626                         dev->trans_start = jiffies;
 627                         spin_unlock_irqrestore(&self->lock, flags);
 628                         dev_kfree_skb(skb);
 629                         return 0;
 630                 } else
 631                         self->new_speed = speed;
 632         }
 633
 634         /* Init tx buffer */
 635         self->tx_buff.data = self->tx_buff.head;
 636
 637         /* Copy skb to tx_buff while wrapping, stuffing and making CRC */
 638         self->tx_buff.len = async_wrap_skb(skb, self->tx_buff.data,
 639                                            self->tx_buff.truesize);
 640
 641         self->stats.tx_bytes += self->tx_buff.len;
 642
 643         /* We are transmitting */
 644         self->transmitting = 1;
 645
 646         /* Turn on transmit finished interrupt. Will fire immediately!  */
 647         outb(UART_IER_THRI, iobase+UART_IER);
 648
 649         dev->trans_start = jiffies;
 650         spin_unlock_irqrestore(&self->lock, flags);
 651
 652         dev_kfree_skb(skb);
 653
 654         return 0;
 655 }
 656
 657 /*
 658  * Function irport_write (driver)
 659  *
 660  *    Fill Tx FIFO with transmit data
 661  *
 662  * Called only from irport_write_wakeup()
 663  */
 664 static inline int irport_write(int iobase, int fifo_size, __u8 *buf, int len)
 665 {
 666         int actual = 0;
 667
 668         /* Fill FIFO with current frame */
 669         while ((actual < fifo_size) && (actual < len)) {
 670                 /* Transmit next byte */
 671                 outb(buf[actual], iobase+UART_TX);
 672
 673                 actual++;
 674         }
 675
 676         return actual;
 677 }
 678
 679 /*
 680  * Function irport_write_wakeup (tty)
 681  *
 682  *    Called by the driver when there's room for more data.  If we have
 683  *    more packets to send, we send them here.
 684  *
 685  * Called only from irport_interrupt()
 686  * Make sure this function is *not* called while we are receiving,
 687  * otherwise we will reset fifo and loose data :-(
 688  */
 689 static inline void irport_write_wakeup(struct irport_cb *self)
 690 {
 691         int actual = 0;
 692         int iobase;
 693         unsigned int fcr;
 694
 695         IRDA_ASSERT(self != NULL, return;);
 696
 697         IRDA_DEBUG(4, "%s()\n", __FUNCTION__);
 698
 699         iobase = self->io.sir_base;
 700
 701         /* Finished with frame?  */
 702         if (self->tx_buff.len > 0)  {
 703                 /* Write data left in transmit buffer */
 704                 actual = irport_write(iobase, self->io.fifo_size,
 705                                       self->tx_buff.data, self->tx_buff.len);
 706                 self->tx_buff.data += actual;
 707                 self->tx_buff.len  -= actual;
 708         } else {
 709                 /*
 710                  *  Now serial buffer is almost free & we can start
 711                  *  transmission of another packet. But first we must check
 712                  *  if we need to change the speed of the hardware
 713                  */
 714                 if (self->new_speed) {
 715                         irport_wait_hw_transmitter_finish(self);
 716                         irda_task_execute(self, __irport_change_speed,
 717                                           irport_change_speed_complete,
 718                                           NULL, (void *) self->new_speed);
 719                         self->new_speed = 0;
 720                 } else {
 721                         /* Tell network layer that we want more frames */
 722                         netif_wake_queue(self->netdev);
 723                 }
 724                 self->stats.tx_packets++;
 725
 726                 /*
 727                  * Reset Rx FIFO to make sure that all reflected transmit data
 728                  * is discarded. This is needed for half duplex operation
 729                  */
 730                 fcr = irport_get_fcr(self->io.speed);
 731                 fcr |= UART_FCR_CLEAR_RCVR;
 732                 outb(fcr, iobase+UART_FCR);
 733
 734                 /* Finished transmitting */
 735                 self->transmitting = 0;
 736
 737                 /* Turn on receive interrupts */
 738                 outb(UART_IER_RDI, iobase+UART_IER);
 739
 740                 IRDA_DEBUG(1, "%s() : finished Tx\n", __FUNCTION__);
 741         }
 742 }
 743
 744 /*
 745  * Function irport_receive (self)
 746  *
 747  *    Receive one frame from the infrared port
 748  *
 749  * Called only from irport_interrupt()
 750  */
 751 static inline void irport_receive(struct irport_cb *self)
 752 {
 753         int boguscount = 0;
 754         int iobase;
 755
 756         IRDA_ASSERT(self != NULL, return;);
 757
 758         iobase = self->io.sir_base;
 759
 760         /*
 761          * Receive all characters in Rx FIFO, unwrap and unstuff them.
 762          * async_unwrap_char will deliver all found frames
 763          */
 764         do {
 765                 async_unwrap_char(self->netdev, &self->stats, &self->rx_buff,
 766                                   inb(iobase+UART_RX));
 767
 768                 /* Make sure we don't stay here too long */
 769                 if (boguscount++ > 32) {
 770                         IRDA_DEBUG(2,"%s(), breaking!\n", __FUNCTION__);
 771                         break;
 772                 }
 773         } while (inb(iobase+UART_LSR) & UART_LSR_DR);
 774 }
 775
 776 /*
 777  * Function irport_interrupt (irq, dev_id, regs)
 778  *
 779  *    Interrupt handler
 780  */
 781 static irqreturn_t irport_interrupt(int irq, void *dev_id,
 782                                     struct pt_regs *regs)
 783 {
 784         struct net_device *dev = (struct net_device *) dev_id;
 785         struct irport_cb *self;
 786         int boguscount = 0;
 787         int iobase;
 788         int iir, lsr;
 789         int handled = 0;
 790
 791         if (!dev) {
 792                 IRDA_WARNING("%s() irq %d for unknown device.\n", __FUNCTION__, irq);
 793                 return IRQ_NONE;
 794         }
 795         self = (struct irport_cb *) dev->priv;
 796
 797         spin_lock(&self->lock);
 798
 799         iobase = self->io.sir_base;
 800
 801         /* Cut'n'paste interrupt routine from serial.c
 802          * This version try to minimise latency and I/O operations.
 803          * Simplified and modified to enforce half duplex operation.
 804          * - Jean II */
 805
 806         /* Check status even is iir reg is cleared, more robust and
 807          * eliminate a read on the I/O bus - Jean II */
 808         do {
 809                 /* Get interrupt status ; Clear interrupt */
 810                 lsr = inb(iobase+UART_LSR);
 811
 812                 /* Are we receiving or transmitting ? */
 813                 if(!self->transmitting) {
 814                         /* Received something ? */
 815                         if (lsr & UART_LSR_DR)
 816                                 irport_receive(self);
 817                 } else {
 818                         /* Room in Tx fifo ? */
 819                         if (lsr & (UART_LSR_THRE | UART_LSR_TEMT))
 820                                 irport_write_wakeup(self);
 821                 }
 822
 823                 /* A bit hackish, but working as expected... Jean II */
 824                 if(lsr & (UART_LSR_THRE | UART_LSR_TEMT | UART_LSR_DR))
 825                         handled = 1;
 826
 827                 /* Make sure we don't stay here to long */
 828                 if (boguscount++ > 10) {
 829                         IRDA_WARNING("%s() irq handler looping : lsr=%02x\n",
 830                                      __FUNCTION__, lsr);
 831                         break;
 832                 }
 833
 834                 /* Read interrupt register */
 835                 iir = inb(iobase+UART_IIR);
 836
 837                 /* Enable this debug only when no other options and at low
 838                  * bit rates, otherwise it may cause Rx overruns (lsr=63).
 839                  * - Jean II */
 840                 IRDA_DEBUG(6, "%s(), iir=%02x, lsr=%02x, iobase=%#x\n",
 841                             __FUNCTION__, iir, lsr, iobase);
 842
 843                 /* As long as interrupt pending... */
 844         } while ((iir & UART_IIR_NO_INT) == 0);
 845
 846         spin_unlock(&self->lock);
 847         return IRQ_RETVAL(handled);
 848 }
 849
 850 /*
 851  * Function irport_net_open (dev)
 852  *
 853  *    Network device is taken up. Usually this is done by "ifconfig irda0 up"
 854  *
 855  */
 856 static int irport_net_open(struct net_device *dev)
 857 {
 858         struct irport_cb *self;
 859         int iobase;
 860         char hwname[16];
 861         unsigned long flags;
 862
 863         IRDA_DEBUG(2, "%s()\n", __FUNCTION__);
 864
 865         IRDA_ASSERT(dev != NULL, return -1;);
 866         self = (struct irport_cb *) dev->priv;
 867
 868         iobase = self->io.sir_base;
 869
 870         if (request_irq(self->io.irq, self->interrupt, 0, dev->name,
 871                         (void *) dev)) {
 872                 IRDA_DEBUG(0, "%s(), unable to allocate irq=%d\n",
 873                            __FUNCTION__, self->io.irq);
 874                 return -EAGAIN;
 875         }
 876
 877         spin_lock_irqsave(&self->lock, flags);
 878         /* Init uart */
 879         irport_start(self);
 880         /* Set 9600 bauds per default, including at the dongle */
 881         irda_task_execute(self, __irport_change_speed,
 882                           irport_change_speed_complete,
 883                           NULL, (void *) 9600);
 884         spin_unlock_irqrestore(&self->lock, flags);
 885
 886
 887         /* Give self a hardware name */
 888         sprintf(hwname, "SIR @ 0x%03x", self->io.sir_base);
 889
 890         /*
 891          * Open new IrLAP layer instance, now that everything should be
 892          * initialized properly
 893          */
 894         self->irlap = irlap_open(dev, &self->qos, hwname);
 895
 896         /* Ready to play! */
 897
 898         netif_start_queue(dev);
 899
 900         return 0;
 901 }
 902
 903 /*
 904  * Function irport_net_close (self)
 905  *
 906  *    Network device is taken down. Usually this is done by
 907  *    "ifconfig irda0 down"
 908  */
 909 static int irport_net_close(struct net_device *dev)
 910 {
 911         struct irport_cb *self;
 912         int iobase;
 913         unsigned long flags;
 914
 915         IRDA_DEBUG(4, "%s()\n", __FUNCTION__);
 916
 917         IRDA_ASSERT(dev != NULL, return -1;);
 918         self = (struct irport_cb *) dev->priv;
 919
 920         IRDA_ASSERT(self != NULL, return -1;);
 921
 922         iobase = self->io.sir_base;
 923
 924         /* Stop device */
 925         netif_stop_queue(dev);
 926
 927         /* Stop and remove instance of IrLAP */
 928         if (self->irlap)
 929                 irlap_close(self->irlap);
 930         self->irlap = NULL;
 931
 932         spin_lock_irqsave(&self->lock, flags);
 933         irport_stop(self);
 934         spin_unlock_irqrestore(&self->lock, flags);
 935
 936         free_irq(self->io.irq, dev);
 937
 938         return 0;
 939 }
 940
 941 /*
 942  * Function irport_is_receiving (self)
 943  *
 944  *    Returns true is we are currently receiving data
 945  *
 946  */
 947 static inline int irport_is_receiving(struct irport_cb *self)
 948 {
 949         return (self->rx_buff.state != OUTSIDE_FRAME);
 950 }
 951
 952 /*
 953  * Function irport_set_dtr_rts (tty, dtr, rts)
 954  *
 955  *    This function can be used by dongles etc. to set or reset the status
 956  *    of the dtr and rts lines
 957  */
 958 static int irport_set_dtr_rts(struct net_device *dev, int dtr, int rts)
 959 {
 960         struct irport_cb *self = dev->priv;
 961         int iobase;
 962
 963         IRDA_ASSERT(self != NULL, return -1;);
 964
 965         iobase = self->io.sir_base;
 966
 967         if (dtr)
 968                 dtr = UART_MCR_DTR;
 969         if (rts)
 970                 rts = UART_MCR_RTS;
 971
 972         outb(dtr|rts|UART_MCR_OUT2, iobase+UART_MCR);
 973
 974         return 0;
 975 }
 976
 977 static int irport_raw_write(struct net_device *dev, __u8 *buf, int len)
 978 {
 979         struct irport_cb *self = (struct irport_cb *) dev->priv;
 980         int actual = 0;
 981         int iobase;
 982
 983         IRDA_ASSERT(self != NULL, return -1;);
 984
 985         iobase = self->io.sir_base;
 986
 987         /* Tx FIFO should be empty! */
 988         if (!(inb(iobase+UART_LSR) & UART_LSR_THRE)) {
 989                 IRDA_DEBUG( 0, "%s(), failed, fifo not empty!\n", __FUNCTION__);
 990                 return -1;
 991         }
 992
 993         /* Fill FIFO with current frame */
 994         while (actual < len) {
 995                 /* Transmit next byte */
 996                 outb(buf[actual], iobase+UART_TX);
 997                 actual++;
 998         }
 999
1000         return actual;
1001 }
1002
1003 /*
1004  * Function irport_net_ioctl (dev, rq, cmd)
1005  *
1006  *    Process IOCTL commands for this device
1007  *
1008  */
1009 static int irport_net_ioctl(struct net_device *dev, struct ifreq *rq, int cmd)
1010 {
1011         struct if_irda_req *irq = (struct if_irda_req *) rq;
1012         struct irport_cb *self;
1013         dongle_t *dongle;
1014         unsigned long flags;
1015         int ret = 0;
1016
1017         IRDA_ASSERT(dev != NULL, return -1;);
1018
1019         self = dev->priv;
1020
1021         IRDA_ASSERT(self != NULL, return -1;);
1022
1023         IRDA_DEBUG(2, "%s(), %s, (cmd=0x%X)\n", __FUNCTION__, dev->name, cmd);
1024
1025         switch (cmd) {
1026         case SIOCSBANDWIDTH: /* Set bandwidth */
1027                 if (!capable(CAP_NET_ADMIN))
1028                         ret = -EPERM;
1029                 else
1030                         irda_task_execute(self, __irport_change_speed, NULL,
1031                                           NULL, (void *) irq->ifr_baudrate);
1032                 break;
1033         case SIOCSDONGLE: /* Set dongle */
1034                 if (!capable(CAP_NET_ADMIN)) {
1035                         ret = -EPERM;
1036                         break;
1037                 }
1038
1039                 /* Locking :
1040                  * irda_device_dongle_init() can't be locked.
1041                  * irda_task_execute() doesn't need to be locked.
1042                  * Jean II
1043                  */
1044
1045                 /* Initialize dongle */
1046                 dongle = irda_device_dongle_init(dev, irq->ifr_dongle);
1047                 if (!dongle)
1048                         break;
1049
1050                 dongle->set_mode    = NULL;
1051                 dongle->read        = NULL;
1052                 dongle->write       = irport_raw_write;
1053                 dongle->set_dtr_rts = irport_set_dtr_rts;
1054
1055                 /* Now initialize the dongle!  */
1056                 dongle->issue->open(dongle, &self->qos);
1057
1058                 /* Reset dongle */
1059                 irda_task_execute(dongle, dongle->issue->reset, NULL, NULL,
1060                                   NULL);
1061
1062                 /* Make dongle available to driver only now to avoid
1063                  * race conditions - Jean II */
1064                 self->dongle = dongle;
1065                 break;
1066         case SIOCSMEDIABUSY: /* Set media busy */
1067                 if (!capable(CAP_NET_ADMIN)) {
1068                         ret = -EPERM;
1069                         break;
1070                 }
1071
1072                 irda_device_set_media_busy(self->netdev, TRUE);
1073                 break;
1074         case SIOCGRECEIVING: /* Check if we are receiving right now */
1075                 irq->ifr_receiving = irport_is_receiving(self);
1076                 break;
1077         case SIOCSDTRRTS:
1078                 if (!capable(CAP_NET_ADMIN)) {
1079                         ret = -EPERM;
1080                         break;
1081                 }
1082
1083                 /* No real need to lock... */
1084                 spin_lock_irqsave(&self->lock, flags);
1085                 irport_set_dtr_rts(dev, irq->ifr_dtr, irq->ifr_rts);
1086                 spin_unlock_irqrestore(&self->lock, flags);
1087                 break;
1088         default:
1089                 ret = -EOPNOTSUPP;
1090         }
1091
1092         return ret;
1093 }
1094
1095 static struct net_device_stats *irport_net_get_stats(struct net_device *dev)
1096 {
1097         struct irport_cb *self = (struct irport_cb *) dev->priv;
1098
1099         return &self->stats;
1100 }
1101
1102 static int __init irport_init(void)
1103 {
1104         int i;
1105
1106         for (i=0; (io[i] < 2000) && (i < 4); i++) {
1107                 if (irport_open(i, io[i], irq[i]) != NULL)
1108                         return 0;
1109         }
1110         /*
1111          * Maybe something failed, but we can still be usable for FIR drivers
1112          */
1113         return 0;
1114 }
1115
1116 /*
1117  * Function irport_cleanup ()
1118  *
1119  *    Close all configured ports
1120  *
1121  */
1122 static void __exit irport_cleanup(void)
1123 {
1124         int i;
1125
1126         IRDA_DEBUG( 4, "%s()\n", __FUNCTION__);
1127
1128         for (i=0; i < 4; i++) {
1129                 if (dev_self[i])
1130                         irport_close(dev_self[i]);
1131         }
1132 }
1133
1134 MODULE_PARM(io, "1-4i");
1135 MODULE_PARM_DESC(io, "Base I/O addresses");
1136 MODULE_PARM(irq, "1-4i");
1137 MODULE_PARM_DESC(irq, "IRQ lines");
1138
1139 MODULE_AUTHOR("Dag Brattli <dagb@cs.uit.no>");
1140 MODULE_DESCRIPTION("Half duplex serial driver for IrDA SIR mode");
1141 MODULE_LICENSE("GPL");
1142
1143 module_init(irport_init);
1144 module_exit(irport_cleanup);
1145