1 /* 2 * Copyright (C) 2009 by Bart Hartgers (bart.hartgers+ark3116@gmail.com) 3 * Original version: 4 * Copyright (C) 2006 5 * Simon Schulz (ark3116_driver <at> auctionant.de) 6 * 7 * ark3116 8 * - implements a driver for the arkmicro ark3116 chipset (vendor=0x6547, 9 * productid=0x0232) (used in a datacable called KQ-U8A) 10 * 11 * Supports full modem status lines, break, hardware flow control. Does not 12 * support software flow control, since I do not know how to enable it in hw. 13 * 14 * This driver is a essentially new implementation. I initially dug 15 * into the old ark3116.c driver and suddenly realized the ark3116 is 16 * a 16450 with a USB interface glued to it. See comments at the 17 * bottom of this file. 18 * 19 * This program is free software; you can redistribute it and/or modify it 20 * under the terms of the GNU General Public License as published by the 21 * Free Software Foundation; either version 2 of the License, or (at your 22 * option) any later version. 23 */ 24 25 #include <linux/kernel.h> 26 #include <linux/init.h> 27 #include <linux/ioctl.h> 28 #include <linux/tty.h> 29 #include <linux/tty_flip.h> 30 #include <linux/module.h> 31 #include <linux/usb.h> 32 #include <linux/usb/serial.h> 33 #include <linux/serial.h> 34 #include <linux/serial_reg.h> 35 #include <linux/uaccess.h> 36 #include <linux/mutex.h> 37 #include <linux/spinlock.h> 38 39 static int debug; 40 /* 41 * Version information 42 */ 43 44 #define DRIVER_VERSION "v0.5" 45 #define DRIVER_AUTHOR "Bart Hartgers <bart.hartgers+ark3116@gmail.com>" 46 #define DRIVER_DESC "USB ARK3116 serial/IrDA driver" 47 #define DRIVER_DEV_DESC "ARK3116 RS232/IrDA" 48 #define DRIVER_NAME "ark3116" 49 50 /* usb timeout of 1 second */ 51 #define ARK_TIMEOUT (1*HZ) 52 53 static struct usb_device_id id_table [] = { 54 { USB_DEVICE(0x6547, 0x0232) }, 55 { USB_DEVICE(0x18ec, 0x3118) }, /* USB to IrDA adapter */ 56 { }, 57 }; 58 MODULE_DEVICE_TABLE(usb, id_table); 59 60 static int is_irda(struct usb_serial *serial) 61 { 62 struct usb_device *dev = serial->dev; 63 if (le16_to_cpu(dev->descriptor.idVendor) == 0x18ec && 64 le16_to_cpu(dev->descriptor.idProduct) == 0x3118) 65 return 1; 66 return 0; 67 } 68 69 struct ark3116_private { 70 wait_queue_head_t delta_msr_wait; 71 struct async_icount icount; 72 int irda; /* 1 for irda device */ 73 74 /* protects hw register updates */ 75 struct mutex hw_lock; 76 77 int quot; /* baudrate divisor */ 78 __u32 lcr; /* line control register value */ 79 __u32 hcr; /* handshake control register (0x8) 80 * value */ 81 __u32 mcr; /* modem contol register value */ 82 83 /* protects the status values below */ 84 spinlock_t status_lock; 85 __u32 msr; /* modem status register value */ 86 __u32 lsr; /* line status register value */ 87 }; 88 89 static int ark3116_write_reg(struct usb_serial *serial, 90 unsigned reg, __u8 val) 91 { 92 int result; 93 /* 0xfe 0x40 are magic values taken from original driver */ 94 result = usb_control_msg(serial->dev, 95 usb_sndctrlpipe(serial->dev, 0), 96 0xfe, 0x40, val, reg, 97 NULL, 0, ARK_TIMEOUT); 98 return result; 99 } 100 101 static int ark3116_read_reg(struct usb_serial *serial, 102 unsigned reg, unsigned char *buf) 103 { 104 int result; 105 /* 0xfe 0xc0 are magic values taken from original driver */ 106 result = usb_control_msg(serial->dev, 107 usb_rcvctrlpipe(serial->dev, 0), 108 0xfe, 0xc0, 0, reg, 109 buf, 1, ARK_TIMEOUT); 110 if (result < 0) 111 return result; 112 else 113 return buf[0]; 114 } 115 116 static inline int calc_divisor(int bps) 117 { 118 /* Original ark3116 made some exceptions in rounding here 119 * because windows did the same. Assume that is not really 120 * necessary. 121 * Crystal is 12MHz, probably because of USB, but we divide by 4? 122 */ 123 return (12000000 + 2*bps) / (4*bps); 124 } 125 126 static int ark3116_attach(struct usb_serial *serial) 127 { 128 struct usb_serial_port *port = serial->port[0]; 129 struct ark3116_private *priv; 130 131 /* make sure we have our end-points */ 132 if ((serial->num_bulk_in == 0) || 133 (serial->num_bulk_out == 0) || 134 (serial->num_interrupt_in == 0)) { 135 dev_err(&serial->dev->dev, 136 "%s - missing endpoint - " 137 "bulk in: %d, bulk out: %d, int in %d\n", 138 KBUILD_MODNAME, 139 serial->num_bulk_in, 140 serial->num_bulk_out, 141 serial->num_interrupt_in); 142 return -EINVAL; 143 } 144 145 priv = kzalloc(sizeof(struct ark3116_private), 146 GFP_KERNEL); 147 if (!priv) 148 return -ENOMEM; 149 150 init_waitqueue_head(&priv->delta_msr_wait); 151 mutex_init(&priv->hw_lock); 152 spin_lock_init(&priv->status_lock); 153 154 priv->irda = is_irda(serial); 155 156 usb_set_serial_port_data(port, priv); 157 158 /* setup the hardware */ 159 ark3116_write_reg(serial, UART_IER, 0); 160 /* disable DMA */ 161 ark3116_write_reg(serial, UART_FCR, 0); 162 /* handshake control */ 163 priv->hcr = 0; 164 ark3116_write_reg(serial, 0x8 , 0); 165 /* modem control */ 166 priv->mcr = 0; 167 ark3116_write_reg(serial, UART_MCR, 0); 168 169 if (!(priv->irda)) { 170 ark3116_write_reg(serial, 0xb , 0); 171 } else { 172 ark3116_write_reg(serial, 0xb , 1); 173 ark3116_write_reg(serial, 0xc , 0); 174 ark3116_write_reg(serial, 0xd , 0x41); 175 ark3116_write_reg(serial, 0xa , 1); 176 } 177 178 /* setup baudrate */ 179 ark3116_write_reg(serial, UART_LCR, UART_LCR_DLAB); 180 181 /* setup for 9600 8N1 */ 182 priv->quot = calc_divisor(9600); 183 ark3116_write_reg(serial, UART_DLL, priv->quot & 0xff); 184 ark3116_write_reg(serial, UART_DLM, (priv->quot>>8) & 0xff); 185 186 priv->lcr = UART_LCR_WLEN8; 187 ark3116_write_reg(serial, UART_LCR, UART_LCR_WLEN8); 188 189 ark3116_write_reg(serial, 0xe, 0); 190 191 if (priv->irda) 192 ark3116_write_reg(serial, 0x9, 0); 193 194 dev_info(&serial->dev->dev, 195 "%s using %s mode\n", 196 KBUILD_MODNAME, 197 priv->irda ? "IrDA" : "RS232"); 198 return 0; 199 } 200 201 static void ark3116_release(struct usb_serial *serial) 202 { 203 struct usb_serial_port *port = serial->port[0]; 204 struct ark3116_private *priv = usb_get_serial_port_data(port); 205 206 /* device is closed, so URBs and DMA should be down */ 207 208 usb_set_serial_port_data(port, NULL); 209 210 mutex_destroy(&priv->hw_lock); 211 212 kfree(priv); 213 } 214 215 static void ark3116_init_termios(struct tty_struct *tty) 216 { 217 struct ktermios *termios = tty->termios; 218 *termios = tty_std_termios; 219 termios->c_cflag = B9600 | CS8 220 | CREAD | HUPCL | CLOCAL; 221 termios->c_ispeed = 9600; 222 termios->c_ospeed = 9600; 223 } 224 225 static void ark3116_set_termios(struct tty_struct *tty, 226 struct usb_serial_port *port, 227 struct ktermios *old_termios) 228 { 229 struct usb_serial *serial = port->serial; 230 struct ark3116_private *priv = usb_get_serial_port_data(port); 231 struct ktermios *termios = tty->termios; 232 unsigned int cflag = termios->c_cflag; 233 int bps = tty_get_baud_rate(tty); 234 int quot; 235 __u8 lcr, hcr, eval; 236 237 /* set data bit count */ 238 switch (cflag & CSIZE) { 239 case CS5: 240 lcr = UART_LCR_WLEN5; 241 break; 242 case CS6: 243 lcr = UART_LCR_WLEN6; 244 break; 245 case CS7: 246 lcr = UART_LCR_WLEN7; 247 break; 248 default: 249 case CS8: 250 lcr = UART_LCR_WLEN8; 251 break; 252 } 253 if (cflag & CSTOPB) 254 lcr |= UART_LCR_STOP; 255 if (cflag & PARENB) 256 lcr |= UART_LCR_PARITY; 257 if (!(cflag & PARODD)) 258 lcr |= UART_LCR_EPAR; 259 #ifdef CMSPAR 260 if (cflag & CMSPAR) 261 lcr |= UART_LCR_SPAR; 262 #endif 263 /* handshake control */ 264 hcr = (cflag & CRTSCTS) ? 0x03 : 0x00; 265 266 /* calc baudrate */ 267 dbg("%s - setting bps to %d", __func__, bps); 268 eval = 0; 269 switch (bps) { 270 case 0: 271 quot = calc_divisor(9600); 272 break; 273 default: 274 if ((bps < 75) || (bps > 3000000)) 275 bps = 9600; 276 quot = calc_divisor(bps); 277 break; 278 case 460800: 279 eval = 1; 280 quot = calc_divisor(bps); 281 break; 282 case 921600: 283 eval = 2; 284 quot = calc_divisor(bps); 285 break; 286 } 287 288 /* Update state: synchronize */ 289 mutex_lock(&priv->hw_lock); 290 291 /* keep old LCR_SBC bit */ 292 lcr |= (priv->lcr & UART_LCR_SBC); 293 294 dbg("%s - setting hcr:0x%02x,lcr:0x%02x,quot:%d", 295 __func__, hcr, lcr, quot); 296 297 /* handshake control */ 298 if (priv->hcr != hcr) { 299 priv->hcr = hcr; 300 ark3116_write_reg(serial, 0x8, hcr); 301 } 302 303 /* baudrate */ 304 if (priv->quot != quot) { 305 priv->quot = quot; 306 priv->lcr = lcr; /* need to write lcr anyway */ 307 308 /* disable DMA since transmit/receive is 309 * shadowed by UART_DLL 310 */ 311 ark3116_write_reg(serial, UART_FCR, 0); 312 313 ark3116_write_reg(serial, UART_LCR, 314 lcr|UART_LCR_DLAB); 315 ark3116_write_reg(serial, UART_DLL, quot & 0xff); 316 ark3116_write_reg(serial, UART_DLM, (quot>>8) & 0xff); 317 318 /* restore lcr */ 319 ark3116_write_reg(serial, UART_LCR, lcr); 320 /* magic baudrate thingy: not sure what it does, 321 * but windows does this as well. 322 */ 323 ark3116_write_reg(serial, 0xe, eval); 324 325 /* enable DMA */ 326 ark3116_write_reg(serial, UART_FCR, UART_FCR_DMA_SELECT); 327 } else if (priv->lcr != lcr) { 328 priv->lcr = lcr; 329 ark3116_write_reg(serial, UART_LCR, lcr); 330 } 331 332 mutex_unlock(&priv->hw_lock); 333 334 /* check for software flow control */ 335 if (I_IXOFF(tty) || I_IXON(tty)) { 336 dev_warn(&serial->dev->dev, 337 "%s: don't know how to do software flow control\n", 338 KBUILD_MODNAME); 339 } 340 341 /* Don't rewrite B0 */ 342 if (tty_termios_baud_rate(termios)) 343 tty_termios_encode_baud_rate(termios, bps, bps); 344 } 345 346 static void ark3116_close(struct usb_serial_port *port) 347 { 348 struct usb_serial *serial = port->serial; 349 350 if (serial->dev) { 351 /* disable DMA */ 352 ark3116_write_reg(serial, UART_FCR, 0); 353 354 /* deactivate interrupts */ 355 ark3116_write_reg(serial, UART_IER, 0); 356 357 /* shutdown any bulk reads that might be going on */ 358 if (serial->num_bulk_out) 359 usb_kill_urb(port->write_urb); 360 if (serial->num_bulk_in) 361 usb_kill_urb(port->read_urb); 362 if (serial->num_interrupt_in) 363 usb_kill_urb(port->interrupt_in_urb); 364 } 365 } 366 367 static int ark3116_open(struct tty_struct *tty, struct usb_serial_port *port) 368 { 369 struct ark3116_private *priv = usb_get_serial_port_data(port); 370 struct usb_serial *serial = port->serial; 371 unsigned char *buf; 372 int result; 373 374 buf = kmalloc(1, GFP_KERNEL); 375 if (buf == NULL) 376 return -ENOMEM; 377 378 result = usb_serial_generic_open(tty, port); 379 if (result) { 380 dbg("%s - usb_serial_generic_open failed: %d", 381 __func__, result); 382 goto err_out; 383 } 384 385 /* setup termios */ 386 if (tty) 387 ark3116_set_termios(tty, port, NULL); 388 389 /* remove any data still left: also clears error state */ 390 ark3116_read_reg(serial, UART_RX, buf); 391 392 /* read modem status */ 393 priv->msr = ark3116_read_reg(serial, UART_MSR, buf); 394 /* read line status */ 395 priv->lsr = ark3116_read_reg(serial, UART_LSR, buf); 396 397 result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL); 398 if (result) { 399 dev_err(&port->dev, "submit irq_in urb failed %d\n", 400 result); 401 ark3116_close(port); 402 goto err_out; 403 } 404 405 /* activate interrupts */ 406 ark3116_write_reg(port->serial, UART_IER, UART_IER_MSI|UART_IER_RLSI); 407 408 /* enable DMA */ 409 ark3116_write_reg(port->serial, UART_FCR, UART_FCR_DMA_SELECT); 410 411 err_out: 412 kfree(buf); 413 return result; 414 } 415 416 static int ark3116_ioctl(struct tty_struct *tty, struct file *file, 417 unsigned int cmd, unsigned long arg) 418 { 419 struct usb_serial_port *port = tty->driver_data; 420 struct ark3116_private *priv = usb_get_serial_port_data(port); 421 struct serial_struct serstruct; 422 void __user *user_arg = (void __user *)arg; 423 424 switch (cmd) { 425 case TIOCGSERIAL: 426 /* XXX: Some of these values are probably wrong. */ 427 memset(&serstruct, 0, sizeof(serstruct)); 428 serstruct.type = PORT_16654; 429 serstruct.line = port->serial->minor; 430 serstruct.port = port->number; 431 serstruct.custom_divisor = 0; 432 serstruct.baud_base = 460800; 433 434 if (copy_to_user(user_arg, &serstruct, sizeof(serstruct))) 435 return -EFAULT; 436 437 return 0; 438 case TIOCSSERIAL: 439 if (copy_from_user(&serstruct, user_arg, sizeof(serstruct))) 440 return -EFAULT; 441 return 0; 442 case TIOCMIWAIT: 443 for (;;) { 444 struct async_icount prev = priv->icount; 445 interruptible_sleep_on(&priv->delta_msr_wait); 446 /* see if a signal did it */ 447 if (signal_pending(current)) 448 return -ERESTARTSYS; 449 if ((prev.rng == priv->icount.rng) && 450 (prev.dsr == priv->icount.dsr) && 451 (prev.dcd == priv->icount.dcd) && 452 (prev.cts == priv->icount.cts)) 453 return -EIO; 454 if ((arg & TIOCM_RNG && 455 (prev.rng != priv->icount.rng)) || 456 (arg & TIOCM_DSR && 457 (prev.dsr != priv->icount.dsr)) || 458 (arg & TIOCM_CD && 459 (prev.dcd != priv->icount.dcd)) || 460 (arg & TIOCM_CTS && 461 (prev.cts != priv->icount.cts))) 462 return 0; 463 } 464 break; 465 case TIOCGICOUNT: { 466 struct serial_icounter_struct icount; 467 struct async_icount cnow = priv->icount; 468 memset(&icount, 0, sizeof(icount)); 469 icount.cts = cnow.cts; 470 icount.dsr = cnow.dsr; 471 icount.rng = cnow.rng; 472 icount.dcd = cnow.dcd; 473 icount.rx = cnow.rx; 474 icount.tx = cnow.tx; 475 icount.frame = cnow.frame; 476 icount.overrun = cnow.overrun; 477 icount.parity = cnow.parity; 478 icount.brk = cnow.brk; 479 icount.buf_overrun = cnow.buf_overrun; 480 if (copy_to_user(user_arg, &icount, sizeof(icount))) 481 return -EFAULT; 482 return 0; 483 } 484 } 485 486 return -ENOIOCTLCMD; 487 } 488 489 static int ark3116_tiocmget(struct tty_struct *tty, struct file *file) 490 { 491 struct usb_serial_port *port = tty->driver_data; 492 struct ark3116_private *priv = usb_get_serial_port_data(port); 493 __u32 status; 494 __u32 ctrl; 495 unsigned long flags; 496 497 mutex_lock(&priv->hw_lock); 498 ctrl = priv->mcr; 499 mutex_unlock(&priv->hw_lock); 500 501 spin_lock_irqsave(&priv->status_lock, flags); 502 status = priv->msr; 503 spin_unlock_irqrestore(&priv->status_lock, flags); 504 505 return (status & UART_MSR_DSR ? TIOCM_DSR : 0) | 506 (status & UART_MSR_CTS ? TIOCM_CTS : 0) | 507 (status & UART_MSR_RI ? TIOCM_RI : 0) | 508 (status & UART_MSR_DCD ? TIOCM_CD : 0) | 509 (ctrl & UART_MCR_DTR ? TIOCM_DTR : 0) | 510 (ctrl & UART_MCR_RTS ? TIOCM_RTS : 0) | 511 (ctrl & UART_MCR_OUT1 ? TIOCM_OUT1 : 0) | 512 (ctrl & UART_MCR_OUT2 ? TIOCM_OUT2 : 0); 513 } 514 515 static int ark3116_tiocmset(struct tty_struct *tty, struct file *file, 516 unsigned set, unsigned clr) 517 { 518 struct usb_serial_port *port = tty->driver_data; 519 struct ark3116_private *priv = usb_get_serial_port_data(port); 520 521 /* we need to take the mutex here, to make sure that the value 522 * in priv->mcr is actually the one that is in the hardware 523 */ 524 525 mutex_lock(&priv->hw_lock); 526 527 if (set & TIOCM_RTS) 528 priv->mcr |= UART_MCR_RTS; 529 if (set & TIOCM_DTR) 530 priv->mcr |= UART_MCR_DTR; 531 if (set & TIOCM_OUT1) 532 priv->mcr |= UART_MCR_OUT1; 533 if (set & TIOCM_OUT2) 534 priv->mcr |= UART_MCR_OUT2; 535 if (clr & TIOCM_RTS) 536 priv->mcr &= ~UART_MCR_RTS; 537 if (clr & TIOCM_DTR) 538 priv->mcr &= ~UART_MCR_DTR; 539 if (clr & TIOCM_OUT1) 540 priv->mcr &= ~UART_MCR_OUT1; 541 if (clr & TIOCM_OUT2) 542 priv->mcr &= ~UART_MCR_OUT2; 543 544 ark3116_write_reg(port->serial, UART_MCR, priv->mcr); 545 546 mutex_unlock(&priv->hw_lock); 547 548 return 0; 549 } 550 551 static void ark3116_break_ctl(struct tty_struct *tty, int break_state) 552 { 553 struct usb_serial_port *port = tty->driver_data; 554 struct ark3116_private *priv = usb_get_serial_port_data(port); 555 556 /* LCR is also used for other things: protect access */ 557 mutex_lock(&priv->hw_lock); 558 559 if (break_state) 560 priv->lcr |= UART_LCR_SBC; 561 else 562 priv->lcr &= ~UART_LCR_SBC; 563 564 ark3116_write_reg(port->serial, UART_LCR, priv->lcr); 565 566 mutex_unlock(&priv->hw_lock); 567 } 568 569 static void ark3116_update_msr(struct usb_serial_port *port, __u8 msr) 570 { 571 struct ark3116_private *priv = usb_get_serial_port_data(port); 572 unsigned long flags; 573 574 spin_lock_irqsave(&priv->status_lock, flags); 575 priv->msr = msr; 576 spin_unlock_irqrestore(&priv->status_lock, flags); 577 578 if (msr & UART_MSR_ANY_DELTA) { 579 /* update input line counters */ 580 if (msr & UART_MSR_DCTS) 581 priv->icount.cts++; 582 if (msr & UART_MSR_DDSR) 583 priv->icount.dsr++; 584 if (msr & UART_MSR_DDCD) 585 priv->icount.dcd++; 586 if (msr & UART_MSR_TERI) 587 priv->icount.rng++; 588 wake_up_interruptible(&priv->delta_msr_wait); 589 } 590 } 591 592 static void ark3116_update_lsr(struct usb_serial_port *port, __u8 lsr) 593 { 594 struct ark3116_private *priv = usb_get_serial_port_data(port); 595 unsigned long flags; 596 597 spin_lock_irqsave(&priv->status_lock, flags); 598 /* combine bits */ 599 priv->lsr |= lsr; 600 spin_unlock_irqrestore(&priv->status_lock, flags); 601 602 if (lsr&UART_LSR_BRK_ERROR_BITS) { 603 if (lsr & UART_LSR_BI) 604 priv->icount.brk++; 605 if (lsr & UART_LSR_FE) 606 priv->icount.frame++; 607 if (lsr & UART_LSR_PE) 608 priv->icount.parity++; 609 if (lsr & UART_LSR_OE) 610 priv->icount.overrun++; 611 } 612 } 613 614 static void ark3116_read_int_callback(struct urb *urb) 615 { 616 struct usb_serial_port *port = urb->context; 617 int status = urb->status; 618 const __u8 *data = urb->transfer_buffer; 619 int result; 620 621 switch (status) { 622 case -ECONNRESET: 623 case -ENOENT: 624 case -ESHUTDOWN: 625 /* this urb is terminated, clean up */ 626 dbg("%s - urb shutting down with status: %d", 627 __func__, status); 628 return; 629 default: 630 dbg("%s - nonzero urb status received: %d", 631 __func__, status); 632 break; 633 case 0: /* success */ 634 /* discovered this by trail and error... */ 635 if ((urb->actual_length == 4) && (data[0] == 0xe8)) { 636 const __u8 id = data[1]&UART_IIR_ID; 637 dbg("%s: iir=%02x", __func__, data[1]); 638 if (id == UART_IIR_MSI) { 639 dbg("%s: msr=%02x", __func__, data[3]); 640 ark3116_update_msr(port, data[3]); 641 break; 642 } else if (id == UART_IIR_RLSI) { 643 dbg("%s: lsr=%02x", __func__, data[2]); 644 ark3116_update_lsr(port, data[2]); 645 break; 646 } 647 } 648 /* 649 * Not sure what this data meant... 650 */ 651 usb_serial_debug_data(debug, &port->dev, 652 __func__, 653 urb->actual_length, 654 urb->transfer_buffer); 655 break; 656 } 657 658 result = usb_submit_urb(urb, GFP_ATOMIC); 659 if (result) 660 dev_err(&urb->dev->dev, 661 "%s - Error %d submitting interrupt urb\n", 662 __func__, result); 663 } 664 665 666 /* Data comes in via the bulk (data) URB, erors/interrupts via the int URB. 667 * This means that we cannot be sure which data byte has an associated error 668 * condition, so we report an error for all data in the next bulk read. 669 * 670 * Actually, there might even be a window between the bulk data leaving the 671 * ark and reading/resetting the lsr in the read_bulk_callback where an 672 * interrupt for the next data block could come in. 673 * Without somekind of ordering on the ark, we would have to report the 674 * error for the next block of data as well... 675 * For now, let's pretend this can't happen. 676 */ 677 678 static void send_to_tty(struct tty_struct *tty, 679 const unsigned char *chars, 680 size_t size, char flag) 681 { 682 if (size == 0) 683 return; 684 if (flag == TTY_NORMAL) { 685 tty_insert_flip_string(tty, chars, size); 686 } else { 687 int i; 688 for (i = 0; i < size; ++i) 689 tty_insert_flip_char(tty, chars[i], flag); 690 } 691 } 692 693 static void ark3116_read_bulk_callback(struct urb *urb) 694 { 695 struct usb_serial_port *port = urb->context; 696 struct ark3116_private *priv = usb_get_serial_port_data(port); 697 const __u8 *data = urb->transfer_buffer; 698 int status = urb->status; 699 struct tty_struct *tty; 700 unsigned long flags; 701 int result; 702 char flag; 703 __u32 lsr; 704 705 switch (status) { 706 case -ECONNRESET: 707 case -ENOENT: 708 case -ESHUTDOWN: 709 /* this urb is terminated, clean up */ 710 dbg("%s - urb shutting down with status: %d", 711 __func__, status); 712 return; 713 default: 714 dbg("%s - nonzero urb status received: %d", 715 __func__, status); 716 break; 717 case 0: /* success */ 718 719 spin_lock_irqsave(&priv->status_lock, flags); 720 lsr = priv->lsr; 721 /* clear error bits */ 722 priv->lsr &= ~UART_LSR_BRK_ERROR_BITS; 723 spin_unlock_irqrestore(&priv->status_lock, flags); 724 725 if (unlikely(lsr & UART_LSR_BI)) 726 flag = TTY_BREAK; 727 else if (unlikely(lsr & UART_LSR_PE)) 728 flag = TTY_PARITY; 729 else if (unlikely(lsr & UART_LSR_FE)) 730 flag = TTY_FRAME; 731 else 732 flag = TTY_NORMAL; 733 734 tty = tty_port_tty_get(&port->port); 735 if (tty) { 736 tty_buffer_request_room(tty, urb->actual_length + 1); 737 /* overrun is special, not associated with a char */ 738 if (unlikely(lsr & UART_LSR_OE)) 739 tty_insert_flip_char(tty, 0, TTY_OVERRUN); 740 send_to_tty(tty, data, urb->actual_length, flag); 741 tty_flip_buffer_push(tty); 742 tty_kref_put(tty); 743 } 744 745 /* Throttle the device if requested by tty */ 746 spin_lock_irqsave(&port->lock, flags); 747 port->throttled = port->throttle_req; 748 if (port->throttled) { 749 spin_unlock_irqrestore(&port->lock, flags); 750 return; 751 } else 752 spin_unlock_irqrestore(&port->lock, flags); 753 } 754 /* Continue reading from device */ 755 result = usb_submit_urb(urb, GFP_ATOMIC); 756 if (result) 757 dev_err(&urb->dev->dev, "%s - failed resubmitting" 758 " read urb, error %d\n", __func__, result); 759 } 760 761 static struct usb_driver ark3116_driver = { 762 .name = "ark3116", 763 .probe = usb_serial_probe, 764 .disconnect = usb_serial_disconnect, 765 .id_table = id_table, 766 .no_dynamic_id = 1, 767 }; 768 769 static struct usb_serial_driver ark3116_device = { 770 .driver = { 771 .owner = THIS_MODULE, 772 .name = "ark3116", 773 }, 774 .id_table = id_table, 775 .usb_driver = &ark3116_driver, 776 .num_ports = 1, 777 .attach = ark3116_attach, 778 .release = ark3116_release, 779 .set_termios = ark3116_set_termios, 780 .init_termios = ark3116_init_termios, 781 .ioctl = ark3116_ioctl, 782 .tiocmget = ark3116_tiocmget, 783 .tiocmset = ark3116_tiocmset, 784 .open = ark3116_open, 785 .close = ark3116_close, 786 .break_ctl = ark3116_break_ctl, 787 .read_int_callback = ark3116_read_int_callback, 788 .read_bulk_callback = ark3116_read_bulk_callback, 789 }; 790 791 static int __init ark3116_init(void) 792 { 793 int retval; 794 795 retval = usb_serial_register(&ark3116_device); 796 if (retval) 797 return retval; 798 retval = usb_register(&ark3116_driver); 799 if (retval == 0) { 800 printk(KERN_INFO "%s:" 801 DRIVER_VERSION ":" 802 DRIVER_DESC "\n", 803 KBUILD_MODNAME); 804 } else 805 usb_serial_deregister(&ark3116_device); 806 return retval; 807 } 808 809 static void __exit ark3116_exit(void) 810 { 811 usb_deregister(&ark3116_driver); 812 usb_serial_deregister(&ark3116_device); 813 } 814 815 module_init(ark3116_init); 816 module_exit(ark3116_exit); 817 MODULE_LICENSE("GPL"); 818 819 MODULE_AUTHOR(DRIVER_AUTHOR); 820 MODULE_DESCRIPTION(DRIVER_DESC); 821 822 module_param(debug, bool, S_IRUGO | S_IWUSR); 823 MODULE_PARM_DESC(debug, "Enable debug"); 824 825 /* 826 * The following describes what I learned from studying the old 827 * ark3116.c driver, disassembling the windows driver, and some lucky 828 * guesses. Since I do not have any datasheet or other 829 * documentation, inaccuracies are almost guaranteed. 830 * 831 * Some specs for the ARK3116 can be found here: 832 * http://web.archive.org/web/20060318000438/ 833 * www.arkmicro.com/en/products/view.php?id=10 834 * On that page, 2 GPIO pins are mentioned: I assume these are the 835 * OUT1 and OUT2 pins of the UART, so I added support for those 836 * through the MCR. Since the pins are not available on my hardware, 837 * I could not verify this. 838 * Also, it states there is "on-chip hardware flow control". I have 839 * discovered how to enable that. Unfortunately, I do not know how to 840 * enable XON/XOFF (software) flow control, which would need support 841 * from the chip as well to work. Because of the wording on the web 842 * page there is a real possibility the chip simply does not support 843 * software flow control. 844 * 845 * I got my ark3116 as part of a mobile phone adapter cable. On the 846 * PCB, the following numbered contacts are present: 847 * 848 * 1:- +5V 849 * 2:o DTR 850 * 3:i RX 851 * 4:i DCD 852 * 5:o RTS 853 * 6:o TX 854 * 7:i RI 855 * 8:i DSR 856 * 10:- 0V 857 * 11:i CTS 858 * 859 * On my chip, all signals seem to be 3.3V, but 5V tolerant. But that 860 * may be different for the one you have ;-). 861 * 862 * The windows driver limits the registers to 0-F, so I assume there 863 * are actually 16 present on the device. 864 * 865 * On an UART interrupt, 4 bytes of data come in on the interrupt 866 * endpoint. The bytes are 0xe8 IIR LSR MSR. 867 * 868 * The baudrate seems to be generated from the 12MHz crystal, using 869 * 4-times subsampling. So quot=12e6/(4*baud). Also see description 870 * of register E. 871 * 872 * Registers 0-7: 873 * These seem to be the same as for a regular 16450. The FCR is set 874 * to UART_FCR_DMA_SELECT (0x8), I guess to enable transfers between 875 * the UART and the USB bridge/DMA engine. 876 * 877 * Register 8: 878 * By trial and error, I found out that bit 0 enables hardware CTS, 879 * stopping TX when CTS is +5V. Bit 1 does the same for RTS, making 880 * RTS +5V when the 3116 cannot transfer the data to the USB bus 881 * (verified by disabling the reading URB). Note that as far as I can 882 * tell, the windows driver does NOT use this, so there might be some 883 * hardware bug or something. 884 * 885 * According to a patch provided here 886 * (http://lkml.org/lkml/2009/7/26/56), the ARK3116 can also be used 887 * as an IrDA dongle. Since I do not have such a thing, I could not 888 * investigate that aspect. However, I can speculate ;-). 889 * 890 * - IrDA encodes data differently than RS232. Most likely, one of 891 * the bits in registers 9..E enables the IR ENDEC (encoder/decoder). 892 * - Depending on the IR transceiver, the input and output need to be 893 * inverted, so there are probably bits for that as well. 894 * - IrDA is half-duplex, so there should be a bit for selecting that. 895 * 896 * This still leaves at least two registers unaccounted for. Perhaps 897 * The chip can do XON/XOFF or CRC in HW? 898 * 899 * Register 9: 900 * Set to 0x00 for IrDA, when the baudrate is initialised. 901 * 902 * Register A: 903 * Set to 0x01 for IrDA, at init. 904 * 905 * Register B: 906 * Set to 0x01 for IrDA, 0x00 for RS232, at init. 907 * 908 * Register C: 909 * Set to 00 for IrDA, at init. 910 * 911 * Register D: 912 * Set to 0x41 for IrDA, at init. 913 * 914 * Register E: 915 * Somekind of baudrate override. The windows driver seems to set 916 * this to 0x00 for normal baudrates, 0x01 for 460800, 0x02 for 921600. 917 * Since 460800 and 921600 cannot be obtained by dividing 3MHz by an integer, 918 * it could be somekind of subdivisor thingy. 919 * However,it does not seem to do anything: selecting 921600 (divisor 3, 920 * reg E=2), still gets 1 MHz. I also checked if registers 9, C or F would 921 * work, but they don't. 922 * 923 * Register F: unknown 924 */ 925