1 /* 2 * usb-serial driver for Quatech SSU-100 3 * 4 * based on ftdi_sio.c and the original serqt_usb.c from Quatech 5 * 6 */ 7 8 #include <linux/errno.h> 9 #include <linux/init.h> 10 #include <linux/slab.h> 11 #include <linux/tty.h> 12 #include <linux/tty_driver.h> 13 #include <linux/tty_flip.h> 14 #include <linux/module.h> 15 #include <linux/serial.h> 16 #include <linux/usb.h> 17 #include <linux/usb/serial.h> 18 #include <linux/serial_reg.h> 19 #include <linux/uaccess.h> 20 21 #define QT_OPEN_CLOSE_CHANNEL 0xca 22 #define QT_SET_GET_DEVICE 0xc2 23 #define QT_SET_GET_REGISTER 0xc0 24 #define QT_GET_SET_PREBUF_TRIG_LVL 0xcc 25 #define QT_SET_ATF 0xcd 26 #define QT_GET_SET_UART 0xc1 27 #define QT_TRANSFER_IN 0xc0 28 #define QT_HW_FLOW_CONTROL_MASK 0xc5 29 #define QT_SW_FLOW_CONTROL_MASK 0xc6 30 31 #define SERIAL_MSR_MASK 0xf0 32 33 #define SERIAL_CRTSCTS ((UART_MCR_RTS << 8) | UART_MSR_CTS) 34 35 #define SERIAL_EVEN_PARITY (UART_LCR_PARITY | UART_LCR_EPAR) 36 37 #define MAX_BAUD_RATE 460800 38 39 #define ATC_DISABLED 0x00 40 #define DUPMODE_BITS 0xc0 41 #define RR_BITS 0x03 42 #define LOOPMODE_BITS 0x41 43 #define RS232_MODE 0x00 44 #define RTSCTS_TO_CONNECTOR 0x40 45 #define CLKS_X4 0x02 46 #define FULLPWRBIT 0x00000080 47 #define NEXT_BOARD_POWER_BIT 0x00000004 48 49 static int debug; 50 51 /* Version Information */ 52 #define DRIVER_VERSION "v0.1" 53 #define DRIVER_DESC "Quatech SSU-100 USB to Serial Driver" 54 55 #define USB_VENDOR_ID_QUATECH 0x061d /* Quatech VID */ 56 #define QUATECH_SSU100 0xC020 /* SSU100 */ 57 58 static const struct usb_device_id id_table[] = { 59 {USB_DEVICE(USB_VENDOR_ID_QUATECH, QUATECH_SSU100)}, 60 {} /* Terminating entry */ 61 }; 62 63 MODULE_DEVICE_TABLE(usb, id_table); 64 65 66 static struct usb_driver ssu100_driver = { 67 .name = "ssu100", 68 .probe = usb_serial_probe, 69 .disconnect = usb_serial_disconnect, 70 .id_table = id_table, 71 .suspend = usb_serial_suspend, 72 .resume = usb_serial_resume, 73 .no_dynamic_id = 1, 74 .supports_autosuspend = 1, 75 }; 76 77 struct ssu100_port_private { 78 spinlock_t status_lock; 79 u8 shadowLSR; 80 u8 shadowMSR; 81 wait_queue_head_t delta_msr_wait; /* Used for TIOCMIWAIT */ 82 struct async_icount icount; 83 }; 84 85 static void ssu100_release(struct usb_serial *serial) 86 { 87 struct ssu100_port_private *priv = usb_get_serial_port_data(*serial->port); 88 89 dbg("%s", __func__); 90 kfree(priv); 91 } 92 93 static inline int ssu100_control_msg(struct usb_device *dev, 94 u8 request, u16 data, u16 index) 95 { 96 return usb_control_msg(dev, usb_sndctrlpipe(dev, 0), 97 request, 0x40, data, index, 98 NULL, 0, 300); 99 } 100 101 static inline int ssu100_setdevice(struct usb_device *dev, u8 *data) 102 { 103 u16 x = ((u16)(data[1] << 8) | (u16)(data[0])); 104 105 return ssu100_control_msg(dev, QT_SET_GET_DEVICE, x, 0); 106 } 107 108 109 static inline int ssu100_getdevice(struct usb_device *dev, u8 *data) 110 { 111 return usb_control_msg(dev, usb_rcvctrlpipe(dev, 0), 112 QT_SET_GET_DEVICE, 0xc0, 0, 0, 113 data, 3, 300); 114 } 115 116 static inline int ssu100_getregister(struct usb_device *dev, 117 unsigned short uart, 118 unsigned short reg, 119 u8 *data) 120 { 121 return usb_control_msg(dev, usb_rcvctrlpipe(dev, 0), 122 QT_SET_GET_REGISTER, 0xc0, reg, 123 uart, data, sizeof(*data), 300); 124 125 } 126 127 128 static inline int ssu100_setregister(struct usb_device *dev, 129 unsigned short uart, 130 unsigned short reg, 131 u16 data) 132 { 133 u16 value = (data << 8) | reg; 134 135 return usb_control_msg(dev, usb_sndctrlpipe(dev, 0), 136 QT_SET_GET_REGISTER, 0x40, value, uart, 137 NULL, 0, 300); 138 139 } 140 141 #define set_mctrl(dev, set) update_mctrl((dev), (set), 0) 142 #define clear_mctrl(dev, clear) update_mctrl((dev), 0, (clear)) 143 144 /* these do not deal with device that have more than 1 port */ 145 static inline int update_mctrl(struct usb_device *dev, unsigned int set, 146 unsigned int clear) 147 { 148 unsigned urb_value; 149 int result; 150 151 if (((set | clear) & (TIOCM_DTR | TIOCM_RTS)) == 0) { 152 dbg("%s - DTR|RTS not being set|cleared", __func__); 153 return 0; /* no change */ 154 } 155 156 clear &= ~set; /* 'set' takes precedence over 'clear' */ 157 urb_value = 0; 158 if (set & TIOCM_DTR) 159 urb_value |= UART_MCR_DTR; 160 if (set & TIOCM_RTS) 161 urb_value |= UART_MCR_RTS; 162 163 result = ssu100_setregister(dev, 0, UART_MCR, urb_value); 164 if (result < 0) 165 dbg("%s Error from MODEM_CTRL urb", __func__); 166 167 return result; 168 } 169 170 static int ssu100_initdevice(struct usb_device *dev) 171 { 172 u8 *data; 173 int result = 0; 174 175 dbg("%s", __func__); 176 177 data = kzalloc(3, GFP_KERNEL); 178 if (!data) 179 return -ENOMEM; 180 181 result = ssu100_getdevice(dev, data); 182 if (result < 0) { 183 dbg("%s - get_device failed %i", __func__, result); 184 goto out; 185 } 186 187 data[1] &= ~FULLPWRBIT; 188 189 result = ssu100_setdevice(dev, data); 190 if (result < 0) { 191 dbg("%s - setdevice failed %i", __func__, result); 192 goto out; 193 } 194 195 result = ssu100_control_msg(dev, QT_GET_SET_PREBUF_TRIG_LVL, 128, 0); 196 if (result < 0) { 197 dbg("%s - set prebuffer level failed %i", __func__, result); 198 goto out; 199 } 200 201 result = ssu100_control_msg(dev, QT_SET_ATF, ATC_DISABLED, 0); 202 if (result < 0) { 203 dbg("%s - set ATFprebuffer level failed %i", __func__, result); 204 goto out; 205 } 206 207 result = ssu100_getdevice(dev, data); 208 if (result < 0) { 209 dbg("%s - get_device failed %i", __func__, result); 210 goto out; 211 } 212 213 data[0] &= ~(RR_BITS | DUPMODE_BITS); 214 data[0] |= CLKS_X4; 215 data[1] &= ~(LOOPMODE_BITS); 216 data[1] |= RS232_MODE; 217 218 result = ssu100_setdevice(dev, data); 219 if (result < 0) { 220 dbg("%s - setdevice failed %i", __func__, result); 221 goto out; 222 } 223 224 out: kfree(data); 225 return result; 226 227 } 228 229 230 static void ssu100_set_termios(struct tty_struct *tty, 231 struct usb_serial_port *port, 232 struct ktermios *old_termios) 233 { 234 struct usb_device *dev = port->serial->dev; 235 struct ktermios *termios = tty->termios; 236 u16 baud, divisor, remainder; 237 unsigned int cflag = termios->c_cflag; 238 u16 urb_value = 0; /* will hold the new flags */ 239 int result; 240 241 dbg("%s", __func__); 242 243 if (cflag & PARENB) { 244 if (cflag & PARODD) 245 urb_value |= UART_LCR_PARITY; 246 else 247 urb_value |= SERIAL_EVEN_PARITY; 248 } 249 250 switch (cflag & CSIZE) { 251 case CS5: 252 urb_value |= UART_LCR_WLEN5; 253 break; 254 case CS6: 255 urb_value |= UART_LCR_WLEN6; 256 break; 257 case CS7: 258 urb_value |= UART_LCR_WLEN7; 259 break; 260 default: 261 case CS8: 262 urb_value |= UART_LCR_WLEN8; 263 break; 264 } 265 266 baud = tty_get_baud_rate(tty); 267 if (!baud) 268 baud = 9600; 269 270 dbg("%s - got baud = %d\n", __func__, baud); 271 272 273 divisor = MAX_BAUD_RATE / baud; 274 remainder = MAX_BAUD_RATE % baud; 275 if (((remainder * 2) >= baud) && (baud != 110)) 276 divisor++; 277 278 urb_value = urb_value << 8; 279 280 result = ssu100_control_msg(dev, QT_GET_SET_UART, divisor, urb_value); 281 if (result < 0) 282 dbg("%s - set uart failed", __func__); 283 284 if (cflag & CRTSCTS) 285 result = ssu100_control_msg(dev, QT_HW_FLOW_CONTROL_MASK, 286 SERIAL_CRTSCTS, 0); 287 else 288 result = ssu100_control_msg(dev, QT_HW_FLOW_CONTROL_MASK, 289 0, 0); 290 if (result < 0) 291 dbg("%s - set HW flow control failed", __func__); 292 293 if (I_IXOFF(tty) || I_IXON(tty)) { 294 u16 x = ((u16)(START_CHAR(tty) << 8) | (u16)(STOP_CHAR(tty))); 295 296 result = ssu100_control_msg(dev, QT_SW_FLOW_CONTROL_MASK, 297 x, 0); 298 } else 299 result = ssu100_control_msg(dev, QT_SW_FLOW_CONTROL_MASK, 300 0, 0); 301 302 if (result < 0) 303 dbg("%s - set SW flow control failed", __func__); 304 305 } 306 307 308 static int ssu100_open(struct tty_struct *tty, struct usb_serial_port *port) 309 { 310 struct usb_device *dev = port->serial->dev; 311 struct ssu100_port_private *priv = usb_get_serial_port_data(port); 312 u8 *data; 313 int result; 314 unsigned long flags; 315 316 dbg("%s - port %d", __func__, port->number); 317 318 data = kzalloc(2, GFP_KERNEL); 319 if (!data) 320 return -ENOMEM; 321 322 result = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0), 323 QT_OPEN_CLOSE_CHANNEL, 324 QT_TRANSFER_IN, 0x01, 325 0, data, 2, 300); 326 if (result < 0) { 327 dbg("%s - open failed %i", __func__, result); 328 kfree(data); 329 return result; 330 } 331 332 spin_lock_irqsave(&priv->status_lock, flags); 333 priv->shadowLSR = data[0]; 334 priv->shadowMSR = data[1]; 335 spin_unlock_irqrestore(&priv->status_lock, flags); 336 337 kfree(data); 338 339 /* set to 9600 */ 340 result = ssu100_control_msg(dev, QT_GET_SET_UART, 0x30, 0x0300); 341 if (result < 0) 342 dbg("%s - set uart failed", __func__); 343 344 if (tty) 345 ssu100_set_termios(tty, port, tty->termios); 346 347 return usb_serial_generic_open(tty, port); 348 } 349 350 static void ssu100_close(struct usb_serial_port *port) 351 { 352 dbg("%s", __func__); 353 usb_serial_generic_close(port); 354 } 355 356 static int get_serial_info(struct usb_serial_port *port, 357 struct serial_struct __user *retinfo) 358 { 359 struct serial_struct tmp; 360 361 if (!retinfo) 362 return -EFAULT; 363 364 memset(&tmp, 0, sizeof(tmp)); 365 tmp.line = port->serial->minor; 366 tmp.port = 0; 367 tmp.irq = 0; 368 tmp.flags = ASYNC_SKIP_TEST | ASYNC_AUTO_IRQ; 369 tmp.xmit_fifo_size = port->bulk_out_size; 370 tmp.baud_base = 9600; 371 tmp.close_delay = 5*HZ; 372 tmp.closing_wait = 30*HZ; 373 374 if (copy_to_user(retinfo, &tmp, sizeof(*retinfo))) 375 return -EFAULT; 376 return 0; 377 } 378 379 static int wait_modem_info(struct usb_serial_port *port, unsigned int arg) 380 { 381 struct ssu100_port_private *priv = usb_get_serial_port_data(port); 382 struct async_icount prev, cur; 383 unsigned long flags; 384 385 spin_lock_irqsave(&priv->status_lock, flags); 386 prev = priv->icount; 387 spin_unlock_irqrestore(&priv->status_lock, flags); 388 389 while (1) { 390 wait_event_interruptible(priv->delta_msr_wait, 391 ((priv->icount.rng != prev.rng) || 392 (priv->icount.dsr != prev.dsr) || 393 (priv->icount.dcd != prev.dcd) || 394 (priv->icount.cts != prev.cts))); 395 396 if (signal_pending(current)) 397 return -ERESTARTSYS; 398 399 spin_lock_irqsave(&priv->status_lock, flags); 400 cur = priv->icount; 401 spin_unlock_irqrestore(&priv->status_lock, flags); 402 403 if ((prev.rng == cur.rng) && 404 (prev.dsr == cur.dsr) && 405 (prev.dcd == cur.dcd) && 406 (prev.cts == cur.cts)) 407 return -EIO; 408 409 if ((arg & TIOCM_RNG && (prev.rng != cur.rng)) || 410 (arg & TIOCM_DSR && (prev.dsr != cur.dsr)) || 411 (arg & TIOCM_CD && (prev.dcd != cur.dcd)) || 412 (arg & TIOCM_CTS && (prev.cts != cur.cts))) 413 return 0; 414 } 415 return 0; 416 } 417 418 static int ssu100_get_icount(struct tty_struct *tty, 419 struct serial_icounter_struct *icount) 420 { 421 struct usb_serial_port *port = tty->driver_data; 422 struct ssu100_port_private *priv = usb_get_serial_port_data(port); 423 struct async_icount cnow = priv->icount; 424 425 icount->cts = cnow.cts; 426 icount->dsr = cnow.dsr; 427 icount->rng = cnow.rng; 428 icount->dcd = cnow.dcd; 429 icount->rx = cnow.rx; 430 icount->tx = cnow.tx; 431 icount->frame = cnow.frame; 432 icount->overrun = cnow.overrun; 433 icount->parity = cnow.parity; 434 icount->brk = cnow.brk; 435 icount->buf_overrun = cnow.buf_overrun; 436 437 return 0; 438 } 439 440 441 442 static int ssu100_ioctl(struct tty_struct *tty, struct file *file, 443 unsigned int cmd, unsigned long arg) 444 { 445 struct usb_serial_port *port = tty->driver_data; 446 447 dbg("%s cmd 0x%04x", __func__, cmd); 448 449 switch (cmd) { 450 case TIOCGSERIAL: 451 return get_serial_info(port, 452 (struct serial_struct __user *) arg); 453 454 case TIOCMIWAIT: 455 return wait_modem_info(port, arg); 456 457 default: 458 break; 459 } 460 461 dbg("%s arg not supported", __func__); 462 463 return -ENOIOCTLCMD; 464 } 465 466 static int ssu100_attach(struct usb_serial *serial) 467 { 468 struct ssu100_port_private *priv; 469 struct usb_serial_port *port = *serial->port; 470 471 dbg("%s", __func__); 472 473 priv = kzalloc(sizeof(*priv), GFP_KERNEL); 474 if (!priv) { 475 dev_err(&port->dev, "%s- kmalloc(%Zd) failed.\n", __func__, 476 sizeof(*priv)); 477 return -ENOMEM; 478 } 479 480 spin_lock_init(&priv->status_lock); 481 init_waitqueue_head(&priv->delta_msr_wait); 482 usb_set_serial_port_data(port, priv); 483 484 return ssu100_initdevice(serial->dev); 485 } 486 487 static int ssu100_tiocmget(struct tty_struct *tty, struct file *file) 488 { 489 struct usb_serial_port *port = tty->driver_data; 490 struct usb_device *dev = port->serial->dev; 491 u8 *d; 492 int r; 493 494 dbg("%s\n", __func__); 495 496 d = kzalloc(2, GFP_KERNEL); 497 if (!d) 498 return -ENOMEM; 499 500 r = ssu100_getregister(dev, 0, UART_MCR, d); 501 if (r < 0) 502 goto mget_out; 503 504 r = ssu100_getregister(dev, 0, UART_MSR, d+1); 505 if (r < 0) 506 goto mget_out; 507 508 r = (d[0] & UART_MCR_DTR ? TIOCM_DTR : 0) | 509 (d[0] & UART_MCR_RTS ? TIOCM_RTS : 0) | 510 (d[1] & UART_MSR_CTS ? TIOCM_CTS : 0) | 511 (d[1] & UART_MSR_DCD ? TIOCM_CAR : 0) | 512 (d[1] & UART_MSR_RI ? TIOCM_RI : 0) | 513 (d[1] & UART_MSR_DSR ? TIOCM_DSR : 0); 514 515 mget_out: 516 kfree(d); 517 return r; 518 } 519 520 static int ssu100_tiocmset(struct tty_struct *tty, struct file *file, 521 unsigned int set, unsigned int clear) 522 { 523 struct usb_serial_port *port = tty->driver_data; 524 struct usb_device *dev = port->serial->dev; 525 526 dbg("%s\n", __func__); 527 return update_mctrl(dev, set, clear); 528 } 529 530 static void ssu100_dtr_rts(struct usb_serial_port *port, int on) 531 { 532 struct usb_device *dev = port->serial->dev; 533 534 dbg("%s\n", __func__); 535 536 mutex_lock(&port->serial->disc_mutex); 537 if (!port->serial->disconnected) { 538 /* Disable flow control */ 539 if (!on && 540 ssu100_setregister(dev, 0, UART_MCR, 0) < 0) 541 dev_err(&port->dev, "error from flowcontrol urb\n"); 542 /* drop RTS and DTR */ 543 if (on) 544 set_mctrl(dev, TIOCM_DTR | TIOCM_RTS); 545 else 546 clear_mctrl(dev, TIOCM_DTR | TIOCM_RTS); 547 } 548 mutex_unlock(&port->serial->disc_mutex); 549 } 550 551 static void ssu100_update_msr(struct usb_serial_port *port, u8 msr) 552 { 553 struct ssu100_port_private *priv = usb_get_serial_port_data(port); 554 unsigned long flags; 555 556 spin_lock_irqsave(&priv->status_lock, flags); 557 priv->shadowMSR = msr; 558 spin_unlock_irqrestore(&priv->status_lock, flags); 559 560 if (msr & UART_MSR_ANY_DELTA) { 561 /* update input line counters */ 562 if (msr & UART_MSR_DCTS) 563 priv->icount.cts++; 564 if (msr & UART_MSR_DDSR) 565 priv->icount.dsr++; 566 if (msr & UART_MSR_DDCD) 567 priv->icount.dcd++; 568 if (msr & UART_MSR_TERI) 569 priv->icount.rng++; 570 wake_up_interruptible(&priv->delta_msr_wait); 571 } 572 } 573 574 static void ssu100_update_lsr(struct usb_serial_port *port, u8 lsr, 575 char *tty_flag) 576 { 577 struct ssu100_port_private *priv = usb_get_serial_port_data(port); 578 unsigned long flags; 579 580 spin_lock_irqsave(&priv->status_lock, flags); 581 priv->shadowLSR = lsr; 582 spin_unlock_irqrestore(&priv->status_lock, flags); 583 584 *tty_flag = TTY_NORMAL; 585 if (lsr & UART_LSR_BRK_ERROR_BITS) { 586 /* we always want to update icount, but we only want to 587 * update tty_flag for one case */ 588 if (lsr & UART_LSR_BI) { 589 priv->icount.brk++; 590 *tty_flag = TTY_BREAK; 591 usb_serial_handle_break(port); 592 } 593 if (lsr & UART_LSR_PE) { 594 priv->icount.parity++; 595 if (*tty_flag == TTY_NORMAL) 596 *tty_flag = TTY_PARITY; 597 } 598 if (lsr & UART_LSR_FE) { 599 priv->icount.frame++; 600 if (*tty_flag == TTY_NORMAL) 601 *tty_flag = TTY_FRAME; 602 } 603 if (lsr & UART_LSR_OE){ 604 priv->icount.overrun++; 605 if (*tty_flag == TTY_NORMAL) 606 *tty_flag = TTY_OVERRUN; 607 } 608 } 609 610 } 611 612 static int ssu100_process_packet(struct urb *urb, 613 struct tty_struct *tty) 614 { 615 struct usb_serial_port *port = urb->context; 616 char *packet = (char *)urb->transfer_buffer; 617 char flag = TTY_NORMAL; 618 u32 len = urb->actual_length; 619 int i; 620 char *ch; 621 622 dbg("%s - port %d", __func__, port->number); 623 624 if ((len >= 4) && 625 (packet[0] == 0x1b) && (packet[1] == 0x1b) && 626 ((packet[2] == 0x00) || (packet[2] == 0x01))) { 627 if (packet[2] == 0x00) { 628 ssu100_update_lsr(port, packet[3], &flag); 629 if (flag == TTY_OVERRUN) 630 tty_insert_flip_char(tty, 0, TTY_OVERRUN); 631 } 632 if (packet[2] == 0x01) 633 ssu100_update_msr(port, packet[3]); 634 635 len -= 4; 636 ch = packet + 4; 637 } else 638 ch = packet; 639 640 if (!len) 641 return 0; /* status only */ 642 643 if (port->port.console && port->sysrq) { 644 for (i = 0; i < len; i++, ch++) { 645 if (!usb_serial_handle_sysrq_char(port, *ch)) 646 tty_insert_flip_char(tty, *ch, flag); 647 } 648 } else 649 tty_insert_flip_string_fixed_flag(tty, ch, flag, len); 650 651 return len; 652 } 653 654 static void ssu100_process_read_urb(struct urb *urb) 655 { 656 struct usb_serial_port *port = urb->context; 657 struct tty_struct *tty; 658 int count; 659 660 dbg("%s", __func__); 661 662 tty = tty_port_tty_get(&port->port); 663 if (!tty) 664 return; 665 666 count = ssu100_process_packet(urb, tty); 667 668 if (count) 669 tty_flip_buffer_push(tty); 670 tty_kref_put(tty); 671 } 672 673 static struct usb_serial_driver ssu100_device = { 674 .driver = { 675 .owner = THIS_MODULE, 676 .name = "ssu100", 677 }, 678 .description = DRIVER_DESC, 679 .id_table = id_table, 680 .usb_driver = &ssu100_driver, 681 .num_ports = 1, 682 .open = ssu100_open, 683 .close = ssu100_close, 684 .attach = ssu100_attach, 685 .release = ssu100_release, 686 .dtr_rts = ssu100_dtr_rts, 687 .process_read_urb = ssu100_process_read_urb, 688 .tiocmget = ssu100_tiocmget, 689 .tiocmset = ssu100_tiocmset, 690 .get_icount = ssu100_get_icount, 691 .ioctl = ssu100_ioctl, 692 .set_termios = ssu100_set_termios, 693 .disconnect = usb_serial_generic_disconnect, 694 }; 695 696 static int __init ssu100_init(void) 697 { 698 int retval; 699 700 dbg("%s", __func__); 701 702 /* register with usb-serial */ 703 retval = usb_serial_register(&ssu100_device); 704 705 if (retval) 706 goto failed_usb_sio_register; 707 708 retval = usb_register(&ssu100_driver); 709 if (retval) 710 goto failed_usb_register; 711 712 printk(KERN_INFO KBUILD_MODNAME ": " DRIVER_VERSION ":" 713 DRIVER_DESC "\n"); 714 715 return 0; 716 717 failed_usb_register: 718 usb_serial_deregister(&ssu100_device); 719 failed_usb_sio_register: 720 return retval; 721 } 722 723 static void __exit ssu100_exit(void) 724 { 725 usb_deregister(&ssu100_driver); 726 usb_serial_deregister(&ssu100_device); 727 } 728 729 module_init(ssu100_init); 730 module_exit(ssu100_exit); 731 732 MODULE_DESCRIPTION(DRIVER_DESC); 733 MODULE_LICENSE("GPL"); 734 735 module_param(debug, bool, S_IRUGO | S_IWUSR); 736 MODULE_PARM_DESC(debug, "Debug enabled or not"); 737