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         if (self->tx_buff.head)
 239                 kfree(self->tx_buff.head);
 240
 241         if (self->rx_buff.skb)
 242                 kfree_skb(self->rx_buff.skb);
 243         self->rx_buff.skb = NULL;
 244
 245         /* Remove ourselves */
 246         dev_self[self->index] = NULL;
 247         free_netdev(self->netdev);
 248
 249         return 0;
 250 }
 251
 252 static void irport_stop(struct irport_cb *self)
 253 {
 254         int iobase;
 255
 256         iobase = self->io.sir_base;
 257
 258         /* We can't lock, we may be called from a FIR driver - Jean II */
 259
 260         /* We are not transmitting any more */
 261         self->transmitting = 0;
 262
 263         /* Reset UART */
 264         outb(0, iobase+UART_MCR);
 265
 266         /* Turn off interrupts */
 267         outb(0, iobase+UART_IER);
 268 }
 269
 270 static void irport_start(struct irport_cb *self)
 271 {
 272         int iobase;
 273
 274         iobase = self->io.sir_base;
 275
 276         irport_stop(self);
 277
 278         /* We can't lock, we may be called from a FIR driver - Jean II */
 279
 280         /* Initialize UART */
 281         outb(UART_LCR_WLEN8, iobase+UART_LCR);  /* Reset DLAB */
 282         outb((UART_MCR_DTR | UART_MCR_RTS | UART_MCR_OUT2), iobase+UART_MCR);
 283
 284         /* Turn on interrups */
 285         outb(UART_IER_RLSI | UART_IER_RDI |UART_IER_THRI, iobase+UART_IER);
 286 }
 287
 288 /*
 289  * Function irport_probe (void)
 290  *
 291  *    Start IO port
 292  *
 293  */
 294 int irport_probe(int iobase)
 295 {
 296         IRDA_DEBUG(4, "%s(), iobase=%#x\n", __FUNCTION__, iobase);
 297
 298         return 0;
 299 }
 300
 301 /*
 302  * Function irport_get_fcr (speed)
 303  *
 304  *    Compute value of fcr
 305  *
 306  */
 307 static inline unsigned int irport_get_fcr(__u32 speed)
 308 {
 309         unsigned int fcr;    /* FIFO control reg */
 310
 311         /* Enable fifos */
 312         fcr = UART_FCR_ENABLE_FIFO;
 313
 314         /*
 315          * Use trigger level 1 to avoid 3 ms. timeout delay at 9600 bps, and
 316          * almost 1,7 ms at 19200 bps. At speeds above that we can just forget
 317          * about this timeout since it will always be fast enough.
 318          */
 319         if (speed < 38400)
 320                 fcr |= UART_FCR_TRIGGER_1;
 321         else
 322                 //fcr |= UART_FCR_TRIGGER_14;
 323                 fcr |= UART_FCR_TRIGGER_8;
 324
 325         return(fcr);
 326 }
 327
 328 /*
 329  * Function irport_change_speed (self, speed)
 330  *
 331  *    Set speed of IrDA port to specified baudrate
 332  *
 333  * This function should be called with irq off and spin-lock.
 334  */
 335 static void irport_change_speed(void *priv, __u32 speed)
 336 {
 337         struct irport_cb *self = (struct irport_cb *) priv;
 338         int iobase;
 339         unsigned int fcr;    /* FIFO control reg */
 340         unsigned int lcr;    /* Line control reg */
 341         int divisor;
 342
 343         IRDA_ASSERT(self != NULL, return;);
 344         IRDA_ASSERT(speed != 0, return;);
 345
 346         IRDA_DEBUG(1, "%s(), Setting speed to: %d - iobase=%#x\n",
 347                     __FUNCTION__, speed, self->io.sir_base);
 348
 349         /* We can't lock, we may be called from a FIR driver - Jean II */
 350
 351         iobase = self->io.sir_base;
 352
 353         /* Update accounting for new speed */
 354         self->io.speed = speed;
 355
 356         /* Turn off interrupts */
 357         outb(0, iobase+UART_IER);
 358
 359         divisor = SPEED_MAX/speed;
 360
 361         /* Get proper fifo configuration */
 362         fcr = irport_get_fcr(speed);
 363
 364         /* IrDA ports use 8N1 */
 365         lcr = UART_LCR_WLEN8;
 366
 367         outb(UART_LCR_DLAB | lcr, iobase+UART_LCR); /* Set DLAB */
 368         outb(divisor & 0xff,      iobase+UART_DLL); /* Set speed */
 369         outb(divisor >> 8,        iobase+UART_DLM);
 370         outb(lcr,                 iobase+UART_LCR); /* Set 8N1  */
 371         outb(fcr,                 iobase+UART_FCR); /* Enable FIFO's */
 372
 373         /* Turn on interrups */
 374         /* This will generate a fatal interrupt storm.
 375          * People calling us will do that properly - Jean II */
 376         //outb(/*UART_IER_RLSI|*/UART_IER_RDI/*|UART_IER_THRI*/, iobase+UART_IER);
 377 }
 378
 379 /*
 380  * Function __irport_change_speed (instance, state, param)
 381  *
 382  *    State machine for changing speed of the device. We do it this way since
 383  *    we cannot use schedule_timeout() when we are in interrupt context
 384  *
 385  */
 386 int __irport_change_speed(struct irda_task *task)
 387 {
 388         struct irport_cb *self;
 389         __u32 speed = (__u32) task->param;
 390         unsigned long flags = 0;
 391         int wasunlocked = 0;
 392         int ret = 0;
 393
 394         IRDA_DEBUG(2, "%s(), <%ld>\n", __FUNCTION__, jiffies);
 395
 396         self = (struct irport_cb *) task->instance;
 397
 398         IRDA_ASSERT(self != NULL, return -1;);
 399
 400         /* Locking notes : this function may be called from irq context with
 401          * spinlock, via irport_write_wakeup(), or from non-interrupt without
 402          * spinlock (from the task timer). Yuck !
 403          * This is ugly, and unsafe is the spinlock is not already aquired.
 404          * This will be fixed when irda-task get rewritten.
 405          * Jean II */
 406         if (!spin_is_locked(&self->lock)) {
 407                 spin_lock_irqsave(&self->lock, flags);
 408                 wasunlocked = 1;
 409         }
 410
 411         switch (task->state) {
 412         case IRDA_TASK_INIT:
 413         case IRDA_TASK_WAIT:
 414                 /* Are we ready to change speed yet? */
 415                 if (self->tx_buff.len > 0) {
 416                         task->state = IRDA_TASK_WAIT;
 417
 418                         /* Try again later */
 419                         ret = msecs_to_jiffies(20);
 420                         break;
 421                 }
 422
 423                 if (self->dongle)
 424                         irda_task_next_state(task, IRDA_TASK_CHILD_INIT);
 425                 else
 426                         irda_task_next_state(task, IRDA_TASK_CHILD_DONE);
 427                 break;
 428         case IRDA_TASK_CHILD_INIT:
 429                 /* Go to default speed */
 430                 self->change_speed(self->priv, 9600);
 431
 432                 /* Change speed of dongle */
 433                 if (irda_task_execute(self->dongle,
 434                                       self->dongle->issue->change_speed,
 435                                       NULL, task, (void *) speed))
 436                 {
 437                         /* Dongle need more time to change its speed */
 438                         irda_task_next_state(task, IRDA_TASK_CHILD_WAIT);
 439
 440                         /* Give dongle 1 sec to finish */
 441                         ret = msecs_to_jiffies(1000);
 442                 } else
 443                         /* Child finished immediately */
 444                         irda_task_next_state(task, IRDA_TASK_CHILD_DONE);
 445                 break;
 446         case IRDA_TASK_CHILD_WAIT:
 447                 IRDA_WARNING("%s(), changing speed of dongle timed out!\n", __FUNCTION__);
 448                 ret = -1;
 449                 break;
 450         case IRDA_TASK_CHILD_DONE:
 451                 /* Finally we are ready to change the speed */
 452                 self->change_speed(self->priv, speed);
 453
 454                 irda_task_next_state(task, IRDA_TASK_DONE);
 455                 break;
 456         default:
 457                 IRDA_ERROR("%s(), unknown state %d\n",
 458                            __FUNCTION__, task->state);
 459                 irda_task_next_state(task, IRDA_TASK_DONE);
 460                 ret = -1;
 461                 break;
 462         }
 463         /* Put stuff in the state we found them - Jean II */
 464         if(wasunlocked) {
 465                 spin_unlock_irqrestore(&self->lock, flags);
 466         }
 467
 468         return ret;
 469 }
 470
 471 /*
 472  * Function irport_change_speed_complete (task)
 473  *
 474  *    Called when the change speed operation completes
 475  *
 476  */
 477 static int irport_change_speed_complete(struct irda_task *task)
 478 {
 479         struct irport_cb *self;
 480
 481         IRDA_DEBUG(1, "%s()\n", __FUNCTION__);
 482
 483         self = (struct irport_cb *) task->instance;
 484
 485         IRDA_ASSERT(self != NULL, return -1;);
 486         IRDA_ASSERT(self->netdev != NULL, return -1;);
 487
 488         /* Finished changing speed, so we are not busy any longer */
 489         /* Signal network layer so it can try to send the frame */
 490
 491         netif_wake_queue(self->netdev);
 492
 493         return 0;
 494 }
 495
 496 /*
 497  * Function irport_timeout (struct net_device *dev)
 498  *
 499  *    The networking layer thinks we timed out.
 500  *
 501  */
 502
 503 static void irport_timeout(struct net_device *dev)
 504 {
 505         struct irport_cb *self;
 506         int iobase;
 507         int iir, lsr;
 508         unsigned long flags;
 509
 510         self = (struct irport_cb *) dev->priv;
 511         IRDA_ASSERT(self != NULL, return;);
 512         iobase = self->io.sir_base;
 513
 514         IRDA_WARNING("%s: transmit timed out, jiffies = %ld, trans_start = %ld\n",
 515                 dev->name, jiffies, dev->trans_start);
 516         spin_lock_irqsave(&self->lock, flags);
 517
 518         /* Debug what's happening... */
 519
 520         /* Get interrupt status */
 521         lsr = inb(iobase+UART_LSR);
 522         /* Read interrupt register */
 523         iir = inb(iobase+UART_IIR);
 524         IRDA_DEBUG(0, "%s(), iir=%02x, lsr=%02x, iobase=%#x\n",
 525                    __FUNCTION__, iir, lsr, iobase);
 526
 527         IRDA_DEBUG(0, "%s(), transmitting=%d, remain=%d, done=%d\n",
 528                    __FUNCTION__, self->transmitting, self->tx_buff.len,
 529                    self->tx_buff.data - self->tx_buff.head);
 530
 531         /* Now, restart the port */
 532         irport_start(self);
 533         self->change_speed(self->priv, self->io.speed);
 534         /* This will re-enable irqs */
 535         outb(/*UART_IER_RLSI|*/UART_IER_RDI/*|UART_IER_THRI*/, iobase+UART_IER);
 536         dev->trans_start = jiffies;
 537         spin_unlock_irqrestore(&self->lock, flags);
 538
 539         netif_wake_queue(dev);
 540 }
 541
 542 /*
 543  * Function irport_wait_hw_transmitter_finish ()
 544  *
 545  *    Wait for the real end of HW transmission
 546  *
 547  * The UART is a strict FIFO, and we get called only when we have finished
 548  * pushing data to the FIFO, so the maximum amount of time we must wait
 549  * is only for the FIFO to drain out.
 550  *
 551  * We use a simple calibrated loop. We may need to adjust the loop
 552  * delay (udelay) to balance I/O traffic and latency. And we also need to
 553  * adjust the maximum timeout.
 554  * It would probably be better to wait for the proper interrupt,
 555  * but it doesn't seem to be available.
 556  *
 557  * We can't use jiffies or kernel timers because :
 558  * 1) We are called from the interrupt handler, which disable softirqs,
 559  * so jiffies won't be increased
 560  * 2) Jiffies granularity is usually very coarse (10ms), and we don't
 561  * want to wait that long to detect stuck hardware.
 562  * Jean II
 563  */
 564
 565 static void irport_wait_hw_transmitter_finish(struct irport_cb *self)
 566 {
 567         int iobase;
 568         int count = 1000;       /* 1 ms */
 569
 570         iobase = self->io.sir_base;
 571
 572         /* Calibrated busy loop */
 573         while((count-- > 0) && !(inb(iobase+UART_LSR) & UART_LSR_TEMT))
 574                 udelay(1);
 575
 576         if(count == 0)
 577                 IRDA_DEBUG(0, "%s(): stuck transmitter\n", __FUNCTION__);
 578 }
 579
 580 /*
 581  * Function irport_hard_start_xmit (struct sk_buff *skb, struct net_device *dev)
 582  *
 583  *    Transmits the current frame until FIFO is full, then
 584  *    waits until the next transmitt interrupt, and continues until the
 585  *    frame is transmitted.
 586  */
 587 static int irport_hard_xmit(struct sk_buff *skb, struct net_device *dev)
 588 {
 589         struct irport_cb *self;
 590         unsigned long flags;
 591         int iobase;
 592         s32 speed;
 593
 594         IRDA_DEBUG(1, "%s()\n", __FUNCTION__);
 595
 596         IRDA_ASSERT(dev != NULL, return 0;);
 597
 598         self = (struct irport_cb *) dev->priv;
 599         IRDA_ASSERT(self != NULL, return 0;);
 600
 601         iobase = self->io.sir_base;
 602
 603         netif_stop_queue(dev);
 604
 605         /* Make sure tests & speed change are atomic */
 606         spin_lock_irqsave(&self->lock, flags);
 607
 608         /* Check if we need to change the speed */
 609         speed = irda_get_next_speed(skb);
 610         if ((speed != self->io.speed) && (speed != -1)) {
 611                 /* Check for empty frame */
 612                 if (!skb->len) {
 613                         /*
 614                          * We send frames one by one in SIR mode (no
 615                          * pipelining), so at this point, if we were sending
 616                          * a previous frame, we just received the interrupt
 617                          * telling us it is finished (UART_IIR_THRI).
 618                          * Therefore, waiting for the transmitter to really
 619                          * finish draining the fifo won't take too long.
 620                          * And the interrupt handler is not expected to run.
 621                          * - Jean II */
 622                         irport_wait_hw_transmitter_finish(self);
 623                         /* Better go there already locked - Jean II */
 624                         irda_task_execute(self, __irport_change_speed,
 625                                           irport_change_speed_complete,
 626                                           NULL, (void *) speed);
 627                         dev->trans_start = jiffies;
 628                         spin_unlock_irqrestore(&self->lock, flags);
 629                         dev_kfree_skb(skb);
 630                         return 0;
 631                 } else
 632                         self->new_speed = speed;
 633         }
 634
 635         /* Init tx buffer */
 636         self->tx_buff.data = self->tx_buff.head;
 637
 638         /* Copy skb to tx_buff while wrapping, stuffing and making CRC */
 639         self->tx_buff.len = async_wrap_skb(skb, self->tx_buff.data,
 640                                            self->tx_buff.truesize);
 641
 642         self->stats.tx_bytes += self->tx_buff.len;
 643
 644         /* We are transmitting */
 645         self->transmitting = 1;
 646
 647         /* Turn on transmit finished interrupt. Will fire immediately!  */
 648         outb(UART_IER_THRI, iobase+UART_IER);
 649
 650         dev->trans_start = jiffies;
 651         spin_unlock_irqrestore(&self->lock, flags);
 652
 653         dev_kfree_skb(skb);
 654
 655         return 0;
 656 }
 657
 658 /*
 659  * Function irport_write (driver)
 660  *
 661  *    Fill Tx FIFO with transmit data
 662  *
 663  * Called only from irport_write_wakeup()
 664  */
 665 static inline int irport_write(int iobase, int fifo_size, __u8 *buf, int len)
 666 {
 667         int actual = 0;
 668
 669         /* Fill FIFO with current frame */
 670         while ((actual < fifo_size) && (actual < len)) {
 671                 /* Transmit next byte */
 672                 outb(buf[actual], iobase+UART_TX);
 673
 674                 actual++;
 675         }
 676
 677         return actual;
 678 }
 679
 680 /*
 681  * Function irport_write_wakeup (tty)
 682  *
 683  *    Called by the driver when there's room for more data.  If we have
 684  *    more packets to send, we send them here.
 685  *
 686  * Called only from irport_interrupt()
 687  * Make sure this function is *not* called while we are receiving,
 688  * otherwise we will reset fifo and loose data :-(
 689  */
 690 static inline void irport_write_wakeup(struct irport_cb *self)
 691 {
 692         int actual = 0;
 693         int iobase;
 694         unsigned int fcr;
 695
 696         IRDA_ASSERT(self != NULL, return;);
 697
 698         IRDA_DEBUG(4, "%s()\n", __FUNCTION__);
 699
 700         iobase = self->io.sir_base;
 701
 702         /* Finished with frame?  */
 703         if (self->tx_buff.len > 0)  {
 704                 /* Write data left in transmit buffer */
 705                 actual = irport_write(iobase, self->io.fifo_size,
 706                                       self->tx_buff.data, self->tx_buff.len);
 707                 self->tx_buff.data += actual;
 708                 self->tx_buff.len  -= actual;
 709         } else {
 710                 /*
 711                  *  Now serial buffer is almost free & we can start
 712                  *  transmission of another packet. But first we must check
 713                  *  if we need to change the speed of the hardware
 714                  */
 715                 if (self->new_speed) {
 716                         irport_wait_hw_transmitter_finish(self);
 717                         irda_task_execute(self, __irport_change_speed,
 718                                           irport_change_speed_complete,
 719                                           NULL, (void *) self->new_speed);
 720                         self->new_speed = 0;
 721                 } else {
 722                         /* Tell network layer that we want more frames */
 723                         netif_wake_queue(self->netdev);
 724                 }
 725                 self->stats.tx_packets++;
 726
 727                 /*
 728                  * Reset Rx FIFO to make sure that all reflected transmit data
 729                  * is discarded. This is needed for half duplex operation
 730                  */
 731                 fcr = irport_get_fcr(self->io.speed);
 732                 fcr |= UART_FCR_CLEAR_RCVR;
 733                 outb(fcr, iobase+UART_FCR);
 734
 735                 /* Finished transmitting */
 736                 self->transmitting = 0;
 737
 738                 /* Turn on receive interrupts */
 739                 outb(UART_IER_RDI, iobase+UART_IER);
 740
 741                 IRDA_DEBUG(1, "%s() : finished Tx\n", __FUNCTION__);
 742         }
 743 }
 744
 745 /*
 746  * Function irport_receive (self)
 747  *
 748  *    Receive one frame from the infrared port
 749  *
 750  * Called only from irport_interrupt()
 751  */
 752 static inline void irport_receive(struct irport_cb *self)
 753 {
 754         int boguscount = 0;
 755         int iobase;
 756
 757         IRDA_ASSERT(self != NULL, return;);
 758
 759         iobase = self->io.sir_base;
 760
 761         /*
 762          * Receive all characters in Rx FIFO, unwrap and unstuff them.
 763          * async_unwrap_char will deliver all found frames
 764          */
 765         do {
 766                 async_unwrap_char(self->netdev, &self->stats, &self->rx_buff,
 767                                   inb(iobase+UART_RX));
 768
 769                 /* Make sure we don't stay here too long */
 770                 if (boguscount++ > 32) {
 771                         IRDA_DEBUG(2,"%s(), breaking!\n", __FUNCTION__);
 772                         break;
 773                 }
 774         } while (inb(iobase+UART_LSR) & UART_LSR_DR);
 775 }
 776
 777 /*
 778  * Function irport_interrupt (irq, dev_id, regs)
 779  *
 780  *    Interrupt handler
 781  */
 782 static irqreturn_t irport_interrupt(int irq, void *dev_id,
 783                                     struct pt_regs *regs)
 784 {
 785         struct net_device *dev = (struct net_device *) dev_id;
 786         struct irport_cb *self;
 787         int boguscount = 0;
 788         int iobase;
 789         int iir, lsr;
 790         int handled = 0;
 791
 792         if (!dev) {
 793                 IRDA_WARNING("%s() irq %d for unknown device.\n", __FUNCTION__, irq);
 794                 return IRQ_NONE;
 795         }
 796         self = (struct irport_cb *) dev->priv;
 797
 798         spin_lock(&self->lock);
 799
 800         iobase = self->io.sir_base;
 801
 802         /* Cut'n'paste interrupt routine from serial.c
 803          * This version try to minimise latency and I/O operations.
 804          * Simplified and modified to enforce half duplex operation.
 805          * - Jean II */
 806
 807         /* Check status even is iir reg is cleared, more robust and
 808          * eliminate a read on the I/O bus - Jean II */
 809         do {
 810                 /* Get interrupt status ; Clear interrupt */
 811                 lsr = inb(iobase+UART_LSR);
 812
 813                 /* Are we receiving or transmitting ? */
 814                 if(!self->transmitting) {
 815                         /* Received something ? */
 816                         if (lsr & UART_LSR_DR)
 817                                 irport_receive(self);
 818                 } else {
 819                         /* Room in Tx fifo ? */
 820                         if (lsr & (UART_LSR_THRE | UART_LSR_TEMT))
 821                                 irport_write_wakeup(self);
 822                 }
 823
 824                 /* A bit hackish, but working as expected... Jean II */
 825                 if(lsr & (UART_LSR_THRE | UART_LSR_TEMT | UART_LSR_DR))
 826                         handled = 1;
 827
 828                 /* Make sure we don't stay here to long */
 829                 if (boguscount++ > 10) {
 830                         IRDA_WARNING("%s() irq handler looping : lsr=%02x\n",
 831                                      __FUNCTION__, lsr);
 832                         break;
 833                 }
 834
 835                 /* Read interrupt register */
 836                 iir = inb(iobase+UART_IIR);
 837
 838                 /* Enable this debug only when no other options and at low
 839                  * bit rates, otherwise it may cause Rx overruns (lsr=63).
 840                  * - Jean II */
 841                 IRDA_DEBUG(6, "%s(), iir=%02x, lsr=%02x, iobase=%#x\n",
 842                             __FUNCTION__, iir, lsr, iobase);
 843
 844                 /* As long as interrupt pending... */
 845         } while ((iir & UART_IIR_NO_INT) == 0);
 846
 847         spin_unlock(&self->lock);
 848         return IRQ_RETVAL(handled);
 849 }
 850
 851 /*
 852  * Function irport_net_open (dev)
 853  *
 854  *    Network device is taken up. Usually this is done by "ifconfig irda0 up"
 855  *
 856  */
 857 static int irport_net_open(struct net_device *dev)
 858 {
 859         struct irport_cb *self;
 860         int iobase;
 861         char hwname[16];
 862         unsigned long flags;
 863
 864         IRDA_DEBUG(2, "%s()\n", __FUNCTION__);
 865
 866         IRDA_ASSERT(dev != NULL, return -1;);
 867         self = (struct irport_cb *) dev->priv;
 868
 869         iobase = self->io.sir_base;
 870
 871         if (request_irq(self->io.irq, self->interrupt, 0, dev->name,
 872                         (void *) dev)) {
 873                 IRDA_DEBUG(0, "%s(), unable to allocate irq=%d\n",
 874                            __FUNCTION__, self->io.irq);
 875                 return -EAGAIN;
 876         }
 877
 878         spin_lock_irqsave(&self->lock, flags);
 879         /* Init uart */
 880         irport_start(self);
 881         /* Set 9600 bauds per default, including at the dongle */
 882         irda_task_execute(self, __irport_change_speed,
 883                           irport_change_speed_complete,
 884                           NULL, (void *) 9600);
 885         spin_unlock_irqrestore(&self->lock, flags);
 886
 887
 888         /* Give self a hardware name */
 889         sprintf(hwname, "SIR @ 0x%03x", self->io.sir_base);
 890
 891         /*
 892          * Open new IrLAP layer instance, now that everything should be
 893          * initialized properly
 894          */
 895         self->irlap = irlap_open(dev, &self->qos, hwname);
 896
 897         /* Ready to play! */
 898
 899         netif_start_queue(dev);
 900
 901         return 0;
 902 }
 903
 904 /*
 905  * Function irport_net_close (self)
 906  *
 907  *    Network device is taken down. Usually this is done by
 908  *    "ifconfig irda0 down"
 909  */
 910 static int irport_net_close(struct net_device *dev)
 911 {
 912         struct irport_cb *self;
 913         int iobase;
 914         unsigned long flags;
 915
 916         IRDA_DEBUG(4, "%s()\n", __FUNCTION__);
 917
 918         IRDA_ASSERT(dev != NULL, return -1;);
 919         self = (struct irport_cb *) dev->priv;
 920
 921         IRDA_ASSERT(self != NULL, return -1;);
 922
 923         iobase = self->io.sir_base;
 924
 925         /* Stop device */
 926         netif_stop_queue(dev);
 927
 928         /* Stop and remove instance of IrLAP */
 929         if (self->irlap)
 930                 irlap_close(self->irlap);
 931         self->irlap = NULL;
 932
 933         spin_lock_irqsave(&self->lock, flags);
 934         irport_stop(self);
 935         spin_unlock_irqrestore(&self->lock, flags);
 936
 937         free_irq(self->io.irq, dev);
 938
 939         return 0;
 940 }
 941
 942 /*
 943  * Function irport_is_receiving (self)
 944  *
 945  *    Returns true is we are currently receiving data
 946  *
 947  */
 948 static inline int irport_is_receiving(struct irport_cb *self)
 949 {
 950         return (self->rx_buff.state != OUTSIDE_FRAME);
 951 }
 952
 953 /*
 954  * Function irport_set_dtr_rts (tty, dtr, rts)
 955  *
 956  *    This function can be used by dongles etc. to set or reset the status
 957  *    of the dtr and rts lines
 958  */
 959 static int irport_set_dtr_rts(struct net_device *dev, int dtr, int rts)
 960 {
 961         struct irport_cb *self = dev->priv;
 962         int iobase;
 963
 964         IRDA_ASSERT(self != NULL, return -1;);
 965
 966         iobase = self->io.sir_base;
 967
 968         if (dtr)
 969                 dtr = UART_MCR_DTR;
 970         if (rts)
 971                 rts = UART_MCR_RTS;
 972
 973         outb(dtr|rts|UART_MCR_OUT2, iobase+UART_MCR);
 974
 975         return 0;
 976 }
 977
 978 static int irport_raw_write(struct net_device *dev, __u8 *buf, int len)
 979 {
 980         struct irport_cb *self = (struct irport_cb *) dev->priv;
 981         int actual = 0;
 982         int iobase;
 983
 984         IRDA_ASSERT(self != NULL, return -1;);
 985
 986         iobase = self->io.sir_base;
 987
 988         /* Tx FIFO should be empty! */
 989         if (!(inb(iobase+UART_LSR) & UART_LSR_THRE)) {
 990                 IRDA_DEBUG( 0, "%s(), failed, fifo not empty!\n", __FUNCTION__);
 991                 return -1;
 992         }
 993
 994         /* Fill FIFO with current frame */
 995         while (actual < len) {
 996                 /* Transmit next byte */
 997                 outb(buf[actual], iobase+UART_TX);
 998                 actual++;
 999         }
1000
1001         return actual;
1002 }
1003
1004 /*
1005  * Function irport_net_ioctl (dev, rq, cmd)
1006  *
1007  *    Process IOCTL commands for this device
1008  *
1009  */
1010 static int irport_net_ioctl(struct net_device *dev, struct ifreq *rq, int cmd)
1011 {
1012         struct if_irda_req *irq = (struct if_irda_req *) rq;
1013         struct irport_cb *self;
1014         dongle_t *dongle;
1015         unsigned long flags;
1016         int ret = 0;
1017
1018         IRDA_ASSERT(dev != NULL, return -1;);
1019
1020         self = dev->priv;
1021
1022         IRDA_ASSERT(self != NULL, return -1;);
1023
1024         IRDA_DEBUG(2, "%s(), %s, (cmd=0x%X)\n", __FUNCTION__, dev->name, cmd);
1025
1026         switch (cmd) {
1027         case SIOCSBANDWIDTH: /* Set bandwidth */
1028                 if (!capable(CAP_NET_ADMIN))
1029                         ret = -EPERM;
1030                 else
1031                         irda_task_execute(self, __irport_change_speed, NULL,
1032                                           NULL, (void *) irq->ifr_baudrate);
1033                 break;
1034         case SIOCSDONGLE: /* Set dongle */
1035                 if (!capable(CAP_NET_ADMIN)) {
1036                         ret = -EPERM;
1037                         break;
1038                 }
1039
1040                 /* Locking :
1041                  * irda_device_dongle_init() can't be locked.
1042                  * irda_task_execute() doesn't need to be locked.
1043                  * Jean II
1044                  */
1045
1046                 /* Initialize dongle */
1047                 dongle = irda_device_dongle_init(dev, irq->ifr_dongle);
1048                 if (!dongle)
1049                         break;
1050
1051                 dongle->set_mode    = NULL;
1052                 dongle->read        = NULL;
1053                 dongle->write       = irport_raw_write;
1054                 dongle->set_dtr_rts = irport_set_dtr_rts;
1055
1056                 /* Now initialize the dongle!  */
1057                 dongle->issue->open(dongle, &self->qos);
1058
1059                 /* Reset dongle */
1060                 irda_task_execute(dongle, dongle->issue->reset, NULL, NULL,
1061                                   NULL);
1062
1063                 /* Make dongle available to driver only now to avoid
1064                  * race conditions - Jean II */
1065                 self->dongle = dongle;
1066                 break;
1067         case SIOCSMEDIABUSY: /* Set media busy */
1068                 if (!capable(CAP_NET_ADMIN)) {
1069                         ret = -EPERM;
1070                         break;
1071                 }
1072
1073                 irda_device_set_media_busy(self->netdev, TRUE);
1074                 break;
1075         case SIOCGRECEIVING: /* Check if we are receiving right now */
1076                 irq->ifr_receiving = irport_is_receiving(self);
1077                 break;
1078         case SIOCSDTRRTS:
1079                 if (!capable(CAP_NET_ADMIN)) {
1080                         ret = -EPERM;
1081                         break;
1082                 }
1083
1084                 /* No real need to lock... */
1085                 spin_lock_irqsave(&self->lock, flags);
1086                 irport_set_dtr_rts(dev, irq->ifr_dtr, irq->ifr_rts);
1087                 spin_unlock_irqrestore(&self->lock, flags);
1088                 break;
1089         default:
1090                 ret = -EOPNOTSUPP;
1091         }
1092
1093         return ret;
1094 }
1095
1096 static struct net_device_stats *irport_net_get_stats(struct net_device *dev)
1097 {
1098         struct irport_cb *self = (struct irport_cb *) dev->priv;
1099
1100         return &self->stats;
1101 }
1102
1103 static int __init irport_init(void)
1104 {
1105         int i;
1106
1107         for (i=0; (io[i] < 2000) && (i < 4); i++) {
1108                 if (irport_open(i, io[i], irq[i]) != NULL)
1109                         return 0;
1110         }
1111         /*
1112          * Maybe something failed, but we can still be usable for FIR drivers
1113          */
1114         return 0;
1115 }
1116
1117 /*
1118  * Function irport_cleanup ()
1119  *
1120  *    Close all configured ports
1121  *
1122  */
1123 static void __exit irport_cleanup(void)
1124 {
1125         int i;
1126
1127         IRDA_DEBUG( 4, "%s()\n", __FUNCTION__);
1128
1129         for (i=0; i < 4; i++) {
1130                 if (dev_self[i])
1131                         irport_close(dev_self[i]);
1132         }
1133 }
1134
1135 MODULE_PARM(io, "1-4i");
1136 MODULE_PARM_DESC(io, "Base I/O addresses");
1137 MODULE_PARM(irq, "1-4i");
1138 MODULE_PARM_DESC(irq, "IRQ lines");
1139
1140 MODULE_AUTHOR("Dag Brattli <dagb@cs.uit.no>");
1141 MODULE_DESCRIPTION("Half duplex serial driver for IrDA SIR mode");
1142 MODULE_LICENSE("GPL");
1143
1144 module_init(irport_init);
1145 module_exit(irport_cleanup);
1146