drivers/net/irda/stir4200.c

   1 /*****************************************************************************
   2 *
   3 * Filename:      stir4200.c
   4 * Version:       0.4
   5 * Description:   Irda SigmaTel USB Dongle
   6 * Status:        Experimental
   7 * Author:        Stephen Hemminger <shemminger@osdl.org>
   8 *
   9 *       Based on earlier driver by Paul Stewart <stewart@parc.com>
  10 *
  11 *       Copyright (C) 2000, Roman Weissgaerber <weissg@vienna.at>
  12 *       Copyright (C) 2001, Dag Brattli <dag@brattli.net>
  13 *       Copyright (C) 2001, Jean Tourrilhes <jt@hpl.hp.com>
  14 *       Copyright (C) 2004, Stephen Hemminger <shemminger@osdl.org>
  15 *
  16 *       This program is free software; you can redistribute it and/or modify
  17 *       it under the terms of the GNU General Public License as published by
  18 *       the Free Software Foundation; either version 2 of the License, or
  19 *       (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., 675 Mass Ave, Cambridge, MA 02139, USA.
  29 *
  30 *****************************************************************************/
  31
  32 /*
  33  * This dongle does no framing, and requires polling to receive the
  34  * data.  The STIr4200 has bulk in and out endpoints just like
  35  * usr-irda devices, but the data it sends and receives is raw; like
  36  * irtty, it needs to call the wrap and unwrap functions to add and
  37  * remove SOF/BOF and escape characters to/from the frame.
  38  */
  39
  40 #include <linux/module.h>
  41 #include <linux/moduleparam.h>
  42
  43 #include <linux/kernel.h>
  44 #include <linux/types.h>
  45 #include <linux/init.h>
  46 #include <linux/time.h>
  47 #include <linux/skbuff.h>
  48 #include <linux/netdevice.h>
  49 #include <linux/slab.h>
  50 #include <linux/delay.h>
  51 #include <linux/usb.h>
  52 #include <linux/crc32.h>
  53 #include <net/irda/irda.h>
  54 #include <net/irda/irlap.h>
  55 #include <net/irda/irda_device.h>
  56 #include <net/irda/wrapper.h>
  57 #include <net/irda/crc.h>
  58 #include <asm/byteorder.h>
  59 #include <asm/unaligned.h>
  60
  61 MODULE_AUTHOR("Stephen Hemminger <shemminger@osdl.org>");
  62 MODULE_DESCRIPTION("IrDA-USB Dongle Driver for SigmaTel STIr4200");
  63 MODULE_LICENSE("GPL");
  64
  65 static int qos_mtt_bits = 0x07; /* 1 ms or more */
  66 module_param(qos_mtt_bits, int, 0);
  67 MODULE_PARM_DESC(qos_mtt_bits, "Minimum Turn Time");
  68
  69 static int rx_sensitivity = 1;  /* FIR 0..4, SIR 0..6 */
  70 module_param(rx_sensitivity, int, 0);
  71 MODULE_PARM_DESC(rx_sensitivity, "Set Receiver sensitivity (0-6, 0 is most sensitive)");
  72
  73 static int tx_power = 0;        /* 0 = highest ... 3 = lowest */
  74 module_param(tx_power, int, 0);
  75 MODULE_PARM_DESC(tx_power, "Set Transmitter power (0-3, 0 is highest power)");
  76
  77 #define STIR_IRDA_HEADER        4
  78 #define CTRL_TIMEOUT            100        /* milliseconds */
  79 #define TRANSMIT_TIMEOUT        200        /* milliseconds */
  80 #define STIR_FIFO_SIZE          4096
  81 #define FIFO_REGS_SIZE          3
  82
  83 enum FirChars {
  84         FIR_CE   = 0x7d,
  85         FIR_XBOF = 0x7f,
  86         FIR_EOF  = 0x7e,
  87 };
  88
  89 enum StirRequests {
  90         REQ_WRITE_REG =         0x00,
  91         REQ_READ_REG =          0x01,
  92         REQ_READ_ROM =          0x02,
  93         REQ_WRITE_SINGLE =      0x03,
  94 };
  95
  96 /* Register offsets */
  97 enum StirRegs {
  98         REG_RSVD=0,
  99         REG_MODE,
 100         REG_PDCLK,
 101         REG_CTRL1,
 102         REG_CTRL2,
 103         REG_FIFOCTL,
 104         REG_FIFOLSB,
 105         REG_FIFOMSB,
 106         REG_DPLL,
 107         REG_IRDIG,
 108         REG_TEST=15,
 109 };
 110
 111 enum StirModeMask {
 112         MODE_FIR = 0x80,
 113         MODE_SIR = 0x20,
 114         MODE_ASK = 0x10,
 115         MODE_FASTRX = 0x08,
 116         MODE_FFRSTEN = 0x04,
 117         MODE_NRESET = 0x02,
 118         MODE_2400 = 0x01,
 119 };
 120
 121 enum StirPdclkMask {
 122         PDCLK_4000000 = 0x02,
 123         PDCLK_115200 = 0x09,
 124         PDCLK_57600 = 0x13,
 125         PDCLK_38400 = 0x1D,
 126         PDCLK_19200 = 0x3B,
 127         PDCLK_9600 = 0x77,
 128         PDCLK_2400 = 0xDF,
 129 };
 130
 131 enum StirCtrl1Mask {
 132         CTRL1_SDMODE = 0x80,
 133         CTRL1_RXSLOW = 0x40,
 134         CTRL1_TXPWD = 0x10,
 135         CTRL1_RXPWD = 0x08,
 136         CTRL1_SRESET = 0x01,
 137 };
 138
 139 enum StirCtrl2Mask {
 140         CTRL2_SPWIDTH = 0x08,
 141         CTRL2_REVID = 0x03,
 142 };
 143
 144 enum StirFifoCtlMask {
 145         FIFOCTL_EOF = 0x80,
 146         FIFOCTL_UNDER = 0x40,
 147         FIFOCTL_OVER = 0x20,
 148         FIFOCTL_DIR = 0x10,
 149         FIFOCTL_CLR = 0x08,
 150         FIFOCTL_EMPTY = 0x04,
 151         FIFOCTL_RXERR = 0x02,
 152         FIFOCTL_TXERR = 0x01,
 153 };
 154
 155 enum StirDiagMask {
 156         IRDIG_RXHIGH = 0x80,
 157         IRDIG_RXLOW = 0x40,
 158 };
 159
 160 enum StirTestMask {
 161         TEST_PLLDOWN = 0x80,
 162         TEST_LOOPIR = 0x40,
 163         TEST_LOOPUSB = 0x20,
 164         TEST_TSTENA = 0x10,
 165         TEST_TSTOSC = 0x0F,
 166 };
 167
 168 struct stir_cb {
 169         struct usb_device *usbdev;      /* init: probe_irda */
 170         struct net_device *netdev;      /* network layer */
 171         struct irlap_cb   *irlap;       /* The link layer we are binded to */
 172         struct net_device_stats stats;  /* network statistics */
 173         struct qos_info   qos;
 174         unsigned          speed;        /* Current speed */
 175
 176         wait_queue_head_t thr_wait;     /* transmit thread wakeup */
 177         struct completion thr_exited;
 178         pid_t             thr_pid;
 179
 180         struct sk_buff    *tx_pending;
 181         void              *io_buf;      /* transmit/receive buffer */
 182         __u8              *fifo_status;
 183
 184         iobuff_t          rx_buff;      /* receive unwrap state machine */
 185         struct timeval    rx_time;
 186         int               receiving;
 187         struct urb       *rx_urb;
 188 };
 189
 190
 191 /* These are the currently known USB ids */
 192 static struct usb_device_id dongles[] = {
 193     /* SigmaTel, Inc,  STIr4200 IrDA/USB Bridge */
 194     { USB_DEVICE(0x066f, 0x4200) },
 195     { }
 196 };
 197
 198 MODULE_DEVICE_TABLE(usb, dongles);
 199
 200 /* Send control message to set dongle register */
 201 static int write_reg(struct stir_cb *stir, __u16 reg, __u8 value)
 202 {
 203         struct usb_device *dev = stir->usbdev;
 204
 205         pr_debug("%s: write reg %d = 0x%x\n",
 206                  stir->netdev->name, reg, value);
 207         return usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
 208                                REQ_WRITE_SINGLE,
 209                                USB_DIR_OUT|USB_TYPE_VENDOR|USB_RECIP_DEVICE,
 210                                value, reg, NULL, 0,
 211                                CTRL_TIMEOUT);
 212 }
 213
 214 /* Send control message to read multiple registers */
 215 static inline int read_reg(struct stir_cb *stir, __u16 reg,
 216                     __u8 *data, __u16 count)
 217 {
 218         struct usb_device *dev = stir->usbdev;
 219
 220         return usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
 221                                REQ_READ_REG,
 222                                USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
 223                                0, reg, data, count,
 224                                CTRL_TIMEOUT);
 225 }
 226
 227 static inline int isfir(u32 speed)
 228 {
 229         return (speed == 4000000);
 230 }
 231
 232 /*
 233  * Prepare a FIR IrDA frame for transmission to the USB dongle.  The
 234  * FIR transmit frame is documented in the datasheet.  It consists of
 235  * a two byte 0x55 0xAA sequence, two little-endian length bytes, a
 236  * sequence of exactly 16 XBOF bytes of 0x7E, two BOF bytes of 0x7E,
 237  * then the data escaped as follows:
 238  *
 239  *    0x7D -> 0x7D 0x5D
 240  *    0x7E -> 0x7D 0x5E
 241  *    0x7F -> 0x7D 0x5F
 242  *
 243  * Then, 4 bytes of little endian (stuffed) FCS follow, then two
 244  * trailing EOF bytes of 0x7E.
 245  */
 246 static inline __u8 *stuff_fir(__u8 *p, __u8 c)
 247 {
 248         switch(c) {
 249         case 0x7d:
 250         case 0x7e:
 251         case 0x7f:
 252                 *p++ = 0x7d;
 253                 c ^= IRDA_TRANS;
 254                 /* fall through */
 255         default:
 256                 *p++ = c;
 257         }
 258         return p;
 259 }
 260
 261 /* Take raw data in skb and put it wrapped into buf */
 262 static unsigned wrap_fir_skb(const struct sk_buff *skb, __u8 *buf)
 263 {
 264         __u8 *ptr = buf;
 265         __u32 fcs = ~(crc32_le(~0, skb->data, skb->len));
 266         __u16 wraplen;
 267         int i;
 268
 269         /* Header */
 270         buf[0] = 0x55;
 271         buf[1] = 0xAA;
 272
 273         ptr = buf + STIR_IRDA_HEADER;
 274         memset(ptr, 0x7f, 16);
 275         ptr += 16;
 276
 277         /* BOF */
 278         *ptr++  = 0x7e;
 279         *ptr++  = 0x7e;
 280
 281         /* Address / Control / Information */
 282         for (i = 0; i < skb->len; i++)
 283                 ptr = stuff_fir(ptr, skb->data[i]);
 284
 285         /* FCS */
 286         ptr = stuff_fir(ptr, fcs & 0xff);
 287         ptr = stuff_fir(ptr, (fcs >> 8) & 0xff);
 288         ptr = stuff_fir(ptr, (fcs >> 16) & 0xff);
 289         ptr = stuff_fir(ptr, (fcs >> 24) & 0xff);
 290
 291         /* EOFs */
 292         *ptr++ = 0x7e;
 293         *ptr++ = 0x7e;
 294
 295         /* Total length, minus the header */
 296         wraplen = (ptr - buf) - STIR_IRDA_HEADER;
 297         buf[2] = wraplen & 0xff;
 298         buf[3] = (wraplen >> 8) & 0xff;
 299
 300         return wraplen + STIR_IRDA_HEADER;
 301 }
 302
 303 static unsigned wrap_sir_skb(struct sk_buff *skb, __u8 *buf)
 304 {
 305         __u16 wraplen;
 306
 307         wraplen = async_wrap_skb(skb, buf + STIR_IRDA_HEADER,
 308                                  STIR_FIFO_SIZE - STIR_IRDA_HEADER);
 309         buf[0] = 0x55;
 310         buf[1] = 0xAA;
 311         buf[2] = wraplen & 0xff;
 312         buf[3] = (wraplen >> 8) & 0xff;
 313
 314         return wraplen + STIR_IRDA_HEADER;
 315 }
 316
 317 /*
 318  * Frame is fully formed in the rx_buff so check crc
 319  * and pass up to irlap
 320  * setup for next receive
 321  */
 322 static void fir_eof(struct stir_cb *stir)
 323 {
 324         iobuff_t *rx_buff = &stir->rx_buff;
 325         int len = rx_buff->len - 4;
 326         struct sk_buff *skb, *nskb;
 327         __u32 fcs;
 328
 329         if (unlikely(len <= 0)) {
 330                 pr_debug("%s: short frame len %d\n",
 331                          stir->netdev->name, len);
 332
 333                 ++stir->stats.rx_errors;
 334                 ++stir->stats.rx_length_errors;
 335                 return;
 336         }
 337
 338         fcs = ~(crc32_le(~0, rx_buff->data, len));
 339         if (fcs != le32_to_cpu(get_unaligned((u32 *)(rx_buff->data+len)))) {
 340                 pr_debug("crc error calc 0x%x len %d\n", fcs, len);
 341                 stir->stats.rx_errors++;
 342                 stir->stats.rx_crc_errors++;
 343                 return;
 344         }
 345
 346         /* if frame is short then just copy it */
 347         if (len < IRDA_RX_COPY_THRESHOLD) {
 348                 nskb = dev_alloc_skb(len + 1);
 349                 if (unlikely(!nskb)) {
 350                         ++stir->stats.rx_dropped;
 351                         return;
 352                 }
 353                 skb_reserve(nskb, 1);
 354                 skb = nskb;
 355                 memcpy(nskb->data, rx_buff->data, len);
 356         } else {
 357                 nskb = dev_alloc_skb(rx_buff->truesize);
 358                 if (unlikely(!nskb)) {
 359                         ++stir->stats.rx_dropped;
 360                         return;
 361                 }
 362                 skb_reserve(nskb, 1);
 363                 skb = rx_buff->skb;
 364                 rx_buff->skb = nskb;
 365                 rx_buff->head = nskb->data;
 366         }
 367
 368         skb_put(skb, len);
 369
 370         skb->mac.raw  = skb->data;
 371         skb->protocol = htons(ETH_P_IRDA);
 372         skb->dev = stir->netdev;
 373
 374         netif_rx(skb);
 375
 376         stir->stats.rx_packets++;
 377         stir->stats.rx_bytes += len;
 378
 379         rx_buff->data = rx_buff->head;
 380         rx_buff->len = 0;
 381 }
 382
 383 /* Unwrap FIR stuffed data and bump it to IrLAP */
 384 static void stir_fir_chars(struct stir_cb *stir,
 385                             const __u8 *bytes, int len)
 386 {
 387         iobuff_t *rx_buff = &stir->rx_buff;
 388         int     i;
 389
 390         for (i = 0; i < len; i++) {
 391                 __u8    byte = bytes[i];
 392
 393                 switch(rx_buff->state) {
 394                 case OUTSIDE_FRAME:
 395                         /* ignore garbage till start of frame */
 396                         if (unlikely(byte != FIR_EOF))
 397                                 continue;
 398                         /* Now receiving frame */
 399                         rx_buff->state = BEGIN_FRAME;
 400
 401                         /* Time to initialize receive buffer */
 402                         rx_buff->data = rx_buff->head;
 403                         rx_buff->len = 0;
 404                         continue;
 405
 406                 case LINK_ESCAPE:
 407                         if (byte == FIR_EOF) {
 408                                 pr_debug("%s: got EOF after escape\n",
 409                                          stir->netdev->name);
 410                                 goto frame_error;
 411                         }
 412                         rx_buff->state = INSIDE_FRAME;
 413                         byte ^= IRDA_TRANS;
 414                         break;
 415
 416                 case BEGIN_FRAME:
 417                         /* ignore multiple BOF/EOF */
 418                         if (byte == FIR_EOF)
 419                                 continue;
 420                         rx_buff->state = INSIDE_FRAME;
 421                         rx_buff->in_frame = TRUE;
 422
 423                         /* fall through */
 424                 case INSIDE_FRAME:
 425                         switch(byte) {
 426                         case FIR_CE:
 427                                 rx_buff->state = LINK_ESCAPE;
 428                                 continue;
 429                         case FIR_XBOF:
 430                                 /* 0x7f is not used in this framing */
 431                                 pr_debug("%s: got XBOF without escape\n",
 432                                          stir->netdev->name);
 433                                 goto frame_error;
 434                         case FIR_EOF:
 435                                 rx_buff->state = OUTSIDE_FRAME;
 436                                 rx_buff->in_frame = FALSE;
 437                                 fir_eof(stir);
 438                                 continue;
 439                         }
 440                         break;
 441                 }
 442
 443                 /* add byte to rx buffer */
 444                 if (unlikely(rx_buff->len >= rx_buff->truesize)) {
 445                         pr_debug("%s: fir frame exceeds %d\n",
 446                                  stir->netdev->name, rx_buff->truesize);
 447                         ++stir->stats.rx_over_errors;
 448                         goto error_recovery;
 449                 }
 450
 451                 rx_buff->data[rx_buff->len++] = byte;
 452                 continue;
 453
 454         frame_error:
 455                 ++stir->stats.rx_frame_errors;
 456
 457         error_recovery:
 458                 ++stir->stats.rx_errors;
 459                 rx_buff->state = OUTSIDE_FRAME;
 460                 rx_buff->in_frame = FALSE;
 461         }
 462 }
 463
 464 /* Unwrap SIR stuffed data and bump it up to IrLAP */
 465 static void stir_sir_chars(struct stir_cb *stir,
 466                             const __u8 *bytes, int len)
 467 {
 468         int i;
 469
 470         for (i = 0; i < len; i++)
 471                 async_unwrap_char(stir->netdev, &stir->stats,
 472                                   &stir->rx_buff, bytes[i]);
 473 }
 474
 475 static inline void unwrap_chars(struct stir_cb *stir,
 476                                 const __u8 *bytes, int length)
 477 {
 478         if (isfir(stir->speed))
 479                 stir_fir_chars(stir, bytes, length);
 480         else
 481                 stir_sir_chars(stir, bytes, length);
 482 }
 483
 484 /* Mode parameters for each speed */
 485 static const struct {
 486         unsigned speed;
 487         __u8 pdclk;
 488 } stir_modes[] = {
 489         { 2400,    PDCLK_2400 },
 490         { 9600,    PDCLK_9600 },
 491         { 19200,   PDCLK_19200 },
 492         { 38400,   PDCLK_38400 },
 493         { 57600,   PDCLK_57600 },
 494         { 115200,  PDCLK_115200 },
 495         { 4000000, PDCLK_4000000 },
 496 };
 497
 498
 499 /*
 500  * Setup chip for speed.
 501  *  Called at startup to initialize the chip
 502  *  and on speed changes.
 503  *
 504  * Note: Write multiple registers doesn't appear to work
 505  */
 506 static int change_speed(struct stir_cb *stir, unsigned speed)
 507 {
 508         int i, err;
 509         __u8 mode;
 510
 511         for (i = 0; i < ARRAY_SIZE(stir_modes); ++i) {
 512                 if (speed == stir_modes[i].speed)
 513                         goto found;
 514         }
 515
 516         warn("%s: invalid speed %d", stir->netdev->name, speed);
 517         return -EINVAL;
 518
 519  found:
 520         pr_debug("speed change from %d to %d\n", stir->speed, speed);
 521
 522         /* Reset modulator */
 523         err = write_reg(stir, REG_CTRL1, CTRL1_SRESET);
 524         if (err)
 525                 goto out;
 526
 527         /* Undocumented magic to tweak the DPLL */
 528         err = write_reg(stir, REG_DPLL, 0x15);
 529         if (err)
 530                 goto out;
 531
 532         /* Set clock */
 533         err = write_reg(stir, REG_PDCLK, stir_modes[i].pdclk);
 534         if (err)
 535                 goto out;
 536
 537         mode = MODE_NRESET | MODE_FASTRX;
 538         if (isfir(speed))
 539                 mode |= MODE_FIR | MODE_FFRSTEN;
 540         else
 541                 mode |= MODE_SIR;
 542
 543         if (speed == 2400)
 544                 mode |= MODE_2400;
 545
 546         err = write_reg(stir, REG_MODE, mode);
 547         if (err)
 548                 goto out;
 549
 550         /* This resets TEMIC style transceiver if any. */
 551         err = write_reg(stir, REG_CTRL1,
 552                         CTRL1_SDMODE | (tx_power & 3) << 1);
 553         if (err)
 554                 goto out;
 555
 556         err = write_reg(stir, REG_CTRL1, (tx_power & 3) << 1);
 557         if (err)
 558                 goto out;
 559
 560         /* Reset sensitivity */
 561         err = write_reg(stir, REG_CTRL2, (rx_sensitivity & 7) << 5);
 562  out:
 563         stir->speed = speed;
 564         return err;
 565 }
 566
 567 /*
 568  * Called from net/core when new frame is available.
 569  */
 570 static int stir_hard_xmit(struct sk_buff *skb, struct net_device *netdev)
 571 {
 572         struct stir_cb *stir = netdev_priv(netdev);
 573
 574         netif_stop_queue(netdev);
 575
 576         /* the IRDA wrapping routines don't deal with non linear skb */
 577         SKB_LINEAR_ASSERT(skb);
 578
 579         skb = xchg(&stir->tx_pending, skb);
 580         wake_up(&stir->thr_wait);
 581
 582         /* this should never happen unless stop/wakeup problem */
 583         if (unlikely(skb)) {
 584                 WARN_ON(1);
 585                 dev_kfree_skb(skb);
 586         }
 587
 588         return 0;
 589 }
 590
 591 /*
 592  * Wait for the transmit FIFO to have space for next data
 593  *
 594  * If space < 0 then wait till FIFO completely drains.
 595  * FYI: can take up to 13 seconds at 2400baud.
 596  */
 597 static int fifo_txwait(struct stir_cb *stir, int space)
 598 {
 599         int err;
 600         unsigned long count, status;
 601
 602         /* Read FIFO status and count */
 603         for(;;) {
 604                 err = read_reg(stir, REG_FIFOCTL, stir->fifo_status,
 605                                    FIFO_REGS_SIZE);
 606                 if (unlikely(err != FIFO_REGS_SIZE)) {
 607                         warn("%s: FIFO register read error: %d",
 608                              stir->netdev->name, err);
 609
 610                         return err;
 611                 }
 612
 613                 status = stir->fifo_status[0];
 614                 count = (unsigned)(stir->fifo_status[2] & 0x1f) << 8
 615                         | stir->fifo_status[1];
 616
 617                 pr_debug("fifo status 0x%lx count %lu\n", status, count);
 618
 619                 /* error when receive/transmit fifo gets confused */
 620                 if (status & FIFOCTL_RXERR) {
 621                         stir->stats.rx_fifo_errors++;
 622                         stir->stats.rx_errors++;
 623                         break;
 624                 }
 625
 626                 if (status & FIFOCTL_TXERR) {
 627                         stir->stats.tx_fifo_errors++;
 628                         stir->stats.tx_errors++;
 629                         break;
 630                 }
 631
 632                 /* is fifo receiving already, or empty */
 633                 if (!(status & FIFOCTL_DIR)
 634                     || (status & FIFOCTL_EMPTY))
 635                         return 0;
 636
 637                 if (signal_pending(current))
 638                         return -EINTR;
 639
 640                 /* shutting down? */
 641                 if (!netif_running(stir->netdev)
 642                     || !netif_device_present(stir->netdev))
 643                         return -ESHUTDOWN;
 644
 645                 /* only waiting for some space */
 646                 if (space >= 0 && STIR_FIFO_SIZE - 4 > space + count)
 647                         return 0;
 648
 649                 /* estimate transfer time for remaining chars */
 650                 msleep((count * 8000) / stir->speed);
 651         }
 652
 653         err = write_reg(stir, REG_FIFOCTL, FIFOCTL_CLR);
 654         if (err)
 655                 return err;
 656         err = write_reg(stir, REG_FIFOCTL, 0);
 657         if (err)
 658                 return err;
 659
 660         return 0;
 661 }
 662
 663
 664 /* Wait for turnaround delay before starting transmit.  */
 665 static void turnaround_delay(const struct stir_cb *stir, long us)
 666 {
 667         long ticks;
 668         struct timeval now;
 669
 670         if (us <= 0)
 671                 return;
 672
 673         do_gettimeofday(&now);
 674         if (now.tv_sec - stir->rx_time.tv_sec > 0)
 675                 us -= USEC_PER_SEC;
 676         us -= now.tv_usec - stir->rx_time.tv_usec;
 677         if (us < 10)
 678                 return;
 679
 680         ticks = us / (1000000 / HZ);
 681         if (ticks > 0) {
 682                 current->state = TASK_INTERRUPTIBLE;
 683                 schedule_timeout(1 + ticks);
 684         } else
 685                 udelay(us);
 686 }
 687
 688 /*
 689  * Start receiver by submitting a request to the receive pipe.
 690  * If nothing is available it will return after rx_interval.
 691  */
 692 static int receive_start(struct stir_cb *stir)
 693 {
 694         /* reset state */
 695         stir->receiving = 1;
 696
 697         stir->rx_buff.in_frame = FALSE;
 698         stir->rx_buff.state = OUTSIDE_FRAME;
 699
 700         stir->rx_urb->status = 0;
 701         return usb_submit_urb(stir->rx_urb, GFP_KERNEL);
 702 }
 703
 704 /* Stop all pending receive Urb's */
 705 static void receive_stop(struct stir_cb *stir)
 706 {
 707         stir->receiving = 0;
 708         usb_kill_urb(stir->rx_urb);
 709
 710         if (stir->rx_buff.in_frame)
 711                 stir->stats.collisions++;
 712 }
 713 /*
 714  * Wrap data in socket buffer and send it.
 715  */
 716 static void stir_send(struct stir_cb *stir, struct sk_buff *skb)
 717 {
 718         unsigned wraplen;
 719         int first_frame = 0;
 720
 721         /* if receiving, need to turnaround */
 722         if (stir->receiving) {
 723                 receive_stop(stir);
 724                 turnaround_delay(stir, irda_get_mtt(skb));
 725                 first_frame = 1;
 726         }
 727
 728         if (isfir(stir->speed))
 729                 wraplen = wrap_fir_skb(skb, stir->io_buf);
 730         else
 731                 wraplen = wrap_sir_skb(skb, stir->io_buf);
 732
 733         /* check for space available in fifo */
 734         if (!first_frame)
 735                 fifo_txwait(stir, wraplen);
 736
 737         stir->stats.tx_packets++;
 738         stir->stats.tx_bytes += skb->len;
 739         stir->netdev->trans_start = jiffies;
 740         pr_debug("send %d (%d)\n", skb->len, wraplen);
 741
 742         if (usb_bulk_msg(stir->usbdev, usb_sndbulkpipe(stir->usbdev, 1),
 743                          stir->io_buf, wraplen,
 744                          NULL, TRANSMIT_TIMEOUT))
 745                 stir->stats.tx_errors++;
 746 }
 747
 748 /*
 749  * Transmit state machine thread
 750  */
 751 static int stir_transmit_thread(void *arg)
 752 {
 753         struct stir_cb *stir = arg;
 754         struct net_device *dev = stir->netdev;
 755         struct sk_buff *skb;
 756
 757         daemonize("%s", dev->name);
 758         allow_signal(SIGTERM);
 759
 760         while (netif_running(dev)
 761                && netif_device_present(dev)
 762                && !signal_pending(current))
 763         {
 764 #ifdef CONFIG_PM
 765                 /* if suspending, then power off and wait */
 766                 if (unlikely(current->flags & PF_FREEZE)) {
 767                         if (stir->receiving)
 768                                 receive_stop(stir);
 769                         else
 770                                 fifo_txwait(stir, -1);
 771
 772                         write_reg(stir, REG_CTRL1, CTRL1_TXPWD|CTRL1_RXPWD);
 773
 774                         refrigerator(PF_FREEZE);
 775
 776                         if (change_speed(stir, stir->speed))
 777                                 break;
 778                 }
 779 #endif
 780
 781                 /* if something to send? */
 782                 skb = xchg(&stir->tx_pending, NULL);
 783                 if (skb) {
 784                         unsigned new_speed = irda_get_next_speed(skb);
 785                         netif_wake_queue(dev);
 786
 787                         if (skb->len > 0)
 788                                 stir_send(stir, skb);
 789                         dev_kfree_skb(skb);
 790
 791                         if ((new_speed != -1) && (stir->speed != new_speed)) {
 792                                 if (fifo_txwait(stir, -1) ||
 793                                     change_speed(stir, new_speed))
 794                                         break;
 795                         }
 796                         continue;
 797                 }
 798
 799                 /* nothing to send? start receiving */
 800                 if (!stir->receiving
 801                     && irda_device_txqueue_empty(dev)) {
 802                         /* Wait otherwise chip gets confused. */
 803                         if (fifo_txwait(stir, -1))
 804                                 break;
 805
 806                         if (unlikely(receive_start(stir))) {
 807                                 if (net_ratelimit())
 808                                         info("%s: receive usb submit failed",
 809                                              stir->netdev->name);
 810                                 stir->receiving = 0;
 811                                 msleep(10);
 812                                 continue;
 813                         }
 814                 }
 815
 816                 /* sleep if nothing to send */
 817                 wait_event_interruptible(stir->thr_wait, stir->tx_pending);
 818         }
 819
 820         complete_and_exit (&stir->thr_exited, 0);
 821 }
 822
 823
 824 /*
 825  * USB bulk receive completion callback.
 826  * Wakes up every ms (usb round trip) with wrapped
 827  * data.
 828  */
 829 static void stir_rcv_irq(struct urb *urb, struct pt_regs *regs)
 830 {
 831         struct stir_cb *stir = urb->context;
 832         int err;
 833
 834         /* in process of stopping, just drop data */
 835         if (!netif_running(stir->netdev))
 836                 return;
 837
 838         /* unlink, shutdown, unplug, other nasties */
 839         if (urb->status != 0)
 840                 return;
 841
 842         if (urb->actual_length > 0) {
 843                 pr_debug("receive %d\n", urb->actual_length);
 844                 unwrap_chars(stir, urb->transfer_buffer,
 845                              urb->actual_length);
 846
 847                 stir->netdev->last_rx = jiffies;
 848                 do_gettimeofday(&stir->rx_time);
 849         }
 850
 851         /* kernel thread is stopping receiver don't resubmit */
 852         if (!stir->receiving)
 853                 return;
 854
 855         /* resubmit existing urb */
 856         err = usb_submit_urb(urb, GFP_ATOMIC);
 857
 858         /* in case of error, the kernel thread will restart us */
 859         if (err) {
 860                 warn("%s: usb receive submit error: %d",
 861                         stir->netdev->name, err);
 862                 stir->receiving = 0;
 863                 wake_up(&stir->thr_wait);
 864         }
 865 }
 866
 867 /*
 868  * Function stir_net_open (dev)
 869  *
 870  *    Network device is taken up. Usually this is done by "ifconfig irda0 up"
 871  */
 872 static int stir_net_open(struct net_device *netdev)
 873 {
 874         struct stir_cb *stir = netdev_priv(netdev);
 875         int err;
 876         char hwname[16];
 877
 878         err = usb_clear_halt(stir->usbdev, usb_sndbulkpipe(stir->usbdev, 1));
 879         if (err)
 880                 goto err_out1;
 881         err = usb_clear_halt(stir->usbdev, usb_rcvbulkpipe(stir->usbdev, 2));
 882         if (err)
 883                 goto err_out1;
 884
 885         err = change_speed(stir, 9600);
 886         if (err)
 887                 goto err_out1;
 888
 889         err = -ENOMEM;
 890
 891         /* Initialize for SIR/FIR to copy data directly into skb.  */
 892         stir->receiving = 0;
 893         stir->rx_buff.truesize = IRDA_SKB_MAX_MTU;
 894         stir->rx_buff.skb = dev_alloc_skb(IRDA_SKB_MAX_MTU);
 895         if (!stir->rx_buff.skb)
 896                 goto err_out1;
 897
 898         skb_reserve(stir->rx_buff.skb, 1);
 899         stir->rx_buff.head = stir->rx_buff.skb->data;
 900         do_gettimeofday(&stir->rx_time);
 901
 902         stir->rx_urb = usb_alloc_urb(0, GFP_KERNEL);
 903         if (!stir->rx_urb)
 904                 goto err_out2;
 905
 906         stir->io_buf = kmalloc(STIR_FIFO_SIZE, GFP_KERNEL);
 907         if (!stir->io_buf)
 908                 goto err_out3;
 909
 910         usb_fill_bulk_urb(stir->rx_urb, stir->usbdev,
 911                           usb_rcvbulkpipe(stir->usbdev, 2),
 912                           stir->io_buf, STIR_FIFO_SIZE,
 913                           stir_rcv_irq, stir);
 914
 915         stir->fifo_status = kmalloc(FIFO_REGS_SIZE, GFP_KERNEL);
 916         if (!stir->fifo_status)
 917                 goto err_out4;
 918
 919         /*
 920          * Now that everything should be initialized properly,
 921          * Open new IrLAP layer instance to take care of us...
 922          * Note : will send immediately a speed change...
 923          */
 924         sprintf(hwname, "usb#%d", stir->usbdev->devnum);
 925         stir->irlap = irlap_open(netdev, &stir->qos, hwname);
 926         if (!stir->irlap) {
 927                 err("stir4200: irlap_open failed");
 928                 goto err_out5;
 929         }
 930
 931         /** Start kernel thread for transmit.  */
 932         stir->thr_pid = kernel_thread(stir_transmit_thread, stir,
 933                                       CLONE_FS|CLONE_FILES);
 934         if (stir->thr_pid < 0) {
 935                 err = stir->thr_pid;
 936                 err("stir4200: unable to start kernel thread");
 937                 goto err_out6;
 938         }
 939
 940         netif_start_queue(netdev);
 941
 942         return 0;
 943
 944  err_out6:
 945         irlap_close(stir->irlap);
 946  err_out5:
 947         kfree(stir->fifo_status);
 948  err_out4:
 949         kfree(stir->io_buf);
 950  err_out3:
 951         usb_free_urb(stir->rx_urb);
 952  err_out2:
 953         kfree_skb(stir->rx_buff.skb);
 954  err_out1:
 955         return err;
 956 }
 957
 958 /*
 959  * Function stir_net_close (stir)
 960  *
 961  *    Network device is taken down. Usually this is done by
 962  *    "ifconfig irda0 down"
 963  */
 964 static int stir_net_close(struct net_device *netdev)
 965 {
 966         struct stir_cb *stir = netdev_priv(netdev);
 967
 968         /* Stop transmit processing */
 969         netif_stop_queue(netdev);
 970
 971         /* Kill transmit thread */
 972         kill_proc(stir->thr_pid, SIGTERM, 1);
 973         wait_for_completion(&stir->thr_exited);
 974         kfree(stir->fifo_status);
 975
 976         /* Mop up receive urb's */
 977         usb_kill_urb(stir->rx_urb);
 978
 979         kfree(stir->io_buf);
 980         usb_free_urb(stir->rx_urb);
 981         kfree_skb(stir->rx_buff.skb);
 982
 983         /* Stop and remove instance of IrLAP */
 984         if (stir->irlap)
 985                 irlap_close(stir->irlap);
 986
 987         stir->irlap = NULL;
 988
 989         return 0;
 990 }
 991
 992 /*
 993  * IOCTLs : Extra out-of-band network commands...
 994  */
 995 static int stir_net_ioctl(struct net_device *netdev, struct ifreq *rq, int cmd)
 996 {
 997         struct if_irda_req *irq = (struct if_irda_req *) rq;
 998         struct stir_cb *stir = netdev_priv(netdev);
 999         int ret = 0;
1000
1001         switch (cmd) {
1002         case SIOCSBANDWIDTH: /* Set bandwidth */
1003                 if (!capable(CAP_NET_ADMIN))
1004                         return -EPERM;
1005
1006                 /* Check if the device is still there */
1007                 if (netif_device_present(stir->netdev))
1008                         ret = change_speed(stir, irq->ifr_baudrate);
1009                 break;
1010
1011         case SIOCSMEDIABUSY: /* Set media busy */
1012                 if (!capable(CAP_NET_ADMIN))
1013                         return -EPERM;
1014
1015                 /* Check if the IrDA stack is still there */
1016                 if (netif_running(stir->netdev))
1017                         irda_device_set_media_busy(stir->netdev, TRUE);
1018                 break;
1019
1020         case SIOCGRECEIVING:
1021                 /* Only approximately true */
1022                 irq->ifr_receiving = stir->receiving;
1023                 break;
1024
1025         default:
1026                 ret = -EOPNOTSUPP;
1027         }
1028
1029         return ret;
1030 }
1031
1032 /*
1033  * Get device stats (for /proc/net/dev and ifconfig)
1034  */
1035 static struct net_device_stats *stir_net_get_stats(struct net_device *netdev)
1036 {
1037         struct stir_cb *stir = netdev_priv(netdev);
1038         return &stir->stats;
1039 }
1040
1041 /*
1042  * This routine is called by the USB subsystem for each new device
1043  * in the system. We need to check if the device is ours, and in
1044  * this case start handling it.
1045  * Note : it might be worth protecting this function by a global
1046  * spinlock... Or not, because maybe USB already deal with that...
1047  */
1048 static int stir_probe(struct usb_interface *intf,
1049                       const struct usb_device_id *id)
1050 {
1051         struct usb_device *dev = interface_to_usbdev(intf);
1052         struct stir_cb *stir = NULL;
1053         struct net_device *net;
1054         int ret = -ENOMEM;
1055
1056         /* Allocate network device container. */
1057         net = alloc_irdadev(sizeof(*stir));
1058         if(!net)
1059                 goto err_out1;
1060
1061         SET_MODULE_OWNER(net);
1062         SET_NETDEV_DEV(net, &intf->dev);
1063         stir = netdev_priv(net);
1064         stir->netdev = net;
1065         stir->usbdev = dev;
1066
1067         ret = usb_reset_configuration(dev);
1068         if (ret != 0) {
1069                 err("stir4200: usb reset configuration failed");
1070                 goto err_out2;
1071         }
1072
1073         printk(KERN_INFO "SigmaTel STIr4200 IRDA/USB found at address %d, "
1074                 "Vendor: %x, Product: %x\n",
1075                dev->devnum, le16_to_cpu(dev->descriptor.idVendor),
1076                le16_to_cpu(dev->descriptor.idProduct));
1077
1078         /* Initialize QoS for this device */
1079         irda_init_max_qos_capabilies(&stir->qos);
1080
1081         /* That's the Rx capability. */
1082         stir->qos.baud_rate.bits       &= IR_2400 | IR_9600 | IR_19200 |
1083                                          IR_38400 | IR_57600 | IR_115200 |
1084                                          (IR_4000000 << 8);
1085         stir->qos.min_turn_time.bits   &= qos_mtt_bits;
1086         irda_qos_bits_to_value(&stir->qos);
1087
1088         init_completion (&stir->thr_exited);
1089         init_waitqueue_head (&stir->thr_wait);
1090
1091         /* Override the network functions we need to use */
1092         net->hard_start_xmit = stir_hard_xmit;
1093         net->open            = stir_net_open;
1094         net->stop            = stir_net_close;
1095         net->get_stats       = stir_net_get_stats;
1096         net->do_ioctl        = stir_net_ioctl;
1097
1098         ret = register_netdev(net);
1099         if (ret != 0)
1100                 goto err_out2;
1101
1102         info("IrDA: Registered SigmaTel device %s", net->name);
1103
1104         usb_set_intfdata(intf, stir);
1105
1106         return 0;
1107
1108 err_out2:
1109         free_netdev(net);
1110 err_out1:
1111         return ret;
1112 }
1113
1114 /*
1115  * The current device is removed, the USB layer tell us to shut it down...
1116  */
1117 static void stir_disconnect(struct usb_interface *intf)
1118 {
1119         struct stir_cb *stir = usb_get_intfdata(intf);
1120
1121         if (!stir)
1122                 return;
1123
1124         unregister_netdev(stir->netdev);
1125         free_netdev(stir->netdev);
1126
1127         usb_set_intfdata(intf, NULL);
1128 }
1129
1130 #ifdef CONFIG_PM
1131 /* Power management suspend, so power off the transmitter/receiver */
1132 static int stir_suspend(struct usb_interface *intf, u32 state)
1133 {
1134         struct stir_cb *stir = usb_get_intfdata(intf);
1135
1136         netif_device_detach(stir->netdev);
1137         return 0;
1138 }
1139
1140 /* Coming out of suspend, so reset hardware */
1141 static int stir_resume(struct usb_interface *intf)
1142 {
1143         struct stir_cb *stir = usb_get_intfdata(intf);
1144
1145         netif_device_attach(stir->netdev);
1146
1147         /* receiver restarted when send thread wakes up */
1148         return 0;
1149 }
1150 #endif
1151
1152 /*
1153  * USB device callbacks
1154  */
1155 static struct usb_driver irda_driver = {
1156         .owner          = THIS_MODULE,
1157         .name           = "stir4200",
1158         .probe          = stir_probe,
1159         .disconnect     = stir_disconnect,
1160         .id_table       = dongles,
1161 #ifdef CONFIG_PM
1162         .suspend        = stir_suspend,
1163         .resume         = stir_resume,
1164 #endif
1165 };
1166
1167 /*
1168  * Module insertion
1169  */
1170 static int __init stir_init(void)
1171 {
1172         return usb_register(&irda_driver);
1173 }
1174 module_init(stir_init);
1175
1176 /*
1177  * Module removal
1178  */
1179 static void __exit stir_cleanup(void)
1180 {
1181         /* Deregister the driver and remove all pending instances */
1182         usb_deregister(&irda_driver);
1183 }
1184 module_exit(stir_cleanup);