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/slab.h> 30#include <linux/tty_flip.h> 31#include <linux/module.h> 32#include <linux/usb.h> 33#include <linux/usb/serial.h> 34#include <linux/serial.h> 35#include <linux/serial_reg.h> 36#include <linux/uaccess.h> 37#include <linux/mutex.h> 38#include <linux/spinlock.h> 39 40static bool debug; 41/* 42 * Version information 43 */ 44 45#define DRIVER_VERSION "v0.7" 46#define DRIVER_AUTHOR "Bart Hartgers <bart.hartgers+ark3116@gmail.com>" 47#define DRIVER_DESC "USB ARK3116 serial/IrDA driver" 48#define DRIVER_DEV_DESC "ARK3116 RS232/IrDA" 49#define DRIVER_NAME "ark3116" 50 51/* usb timeout of 1 second */ 52#define ARK_TIMEOUT (1*HZ) 53 54static const struct usb_device_id id_table[] = { 55 { USB_DEVICE(0x6547, 0x0232) }, 56 { USB_DEVICE(0x18ec, 0x3118) }, /* USB to IrDA adapter */ 57 { }, 58}; 59MODULE_DEVICE_TABLE(usb, id_table); 60 61static int is_irda(struct usb_serial *serial) 62{ 63 struct usb_device *dev = serial->dev; 64 if (le16_to_cpu(dev->descriptor.idVendor) == 0x18ec && 65 le16_to_cpu(dev->descriptor.idProduct) == 0x3118) 66 return 1; 67 return 0; 68} 69 70struct ark3116_private { 71 wait_queue_head_t delta_msr_wait; 72 struct async_icount icount; 73 int irda; /* 1 for irda device */ 74 75 /* protects hw register updates */ 76 struct mutex hw_lock; 77 78 int quot; /* baudrate divisor */ 79 __u32 lcr; /* line control register value */ 80 __u32 hcr; /* handshake control register (0x8) 81 * value */ 82 __u32 mcr; /* modem contol register value */ 83 84 /* protects the status values below */ 85 spinlock_t status_lock; 86 __u32 msr; /* modem status register value */ 87 __u32 lsr; /* line status register value */ 88}; 89 90static int ark3116_write_reg(struct usb_serial *serial, 91 unsigned reg, __u8 val) 92{ 93 int result; 94 /* 0xfe 0x40 are magic values taken from original driver */ 95 result = usb_control_msg(serial->dev, 96 usb_sndctrlpipe(serial->dev, 0), 97 0xfe, 0x40, val, reg, 98 NULL, 0, ARK_TIMEOUT); 99 return result; 100} 101 102static int ark3116_read_reg(struct usb_serial *serial, 103 unsigned reg, unsigned char *buf) 104{ 105 int result; 106 /* 0xfe 0xc0 are magic values taken from original driver */ 107 result = usb_control_msg(serial->dev, 108 usb_rcvctrlpipe(serial->dev, 0), 109 0xfe, 0xc0, 0, reg, 110 buf, 1, ARK_TIMEOUT); 111 if (result < 0) 112 return result; 113 else 114 return buf[0]; 115} 116 117static inline int calc_divisor(int bps) 118{ 119 /* Original ark3116 made some exceptions in rounding here 120 * because windows did the same. Assume that is not really 121 * necessary. 122 * Crystal is 12MHz, probably because of USB, but we divide by 4? 123 */ 124 return (12000000 + 2*bps) / (4*bps); 125} 126 127static int ark3116_attach(struct usb_serial *serial) 128{ 129 struct usb_serial_port *port = serial->port[0]; 130 struct ark3116_private *priv; 131 132 /* make sure we have our end-points */ 133 if ((serial->num_bulk_in == 0) || 134 (serial->num_bulk_out == 0) || 135 (serial->num_interrupt_in == 0)) { 136 dev_err(&serial->dev->dev, 137 "%s - missing endpoint - " 138 "bulk in: %d, bulk out: %d, int in %d\n", 139 KBUILD_MODNAME, 140 serial->num_bulk_in, 141 serial->num_bulk_out, 142 serial->num_interrupt_in); 143 return -EINVAL; 144 } 145 146 priv = kzalloc(sizeof(struct ark3116_private), 147 GFP_KERNEL); 148 if (!priv) 149 return -ENOMEM; 150 151 init_waitqueue_head(&priv->delta_msr_wait); 152 mutex_init(&priv->hw_lock); 153 spin_lock_init(&priv->status_lock); 154 155 priv->irda = is_irda(serial); 156 157 usb_set_serial_port_data(port, priv); 158 159 /* setup the hardware */ 160 ark3116_write_reg(serial, UART_IER, 0); 161 /* disable DMA */ 162 ark3116_write_reg(serial, UART_FCR, 0); 163 /* handshake control */ 164 priv->hcr = 0; 165 ark3116_write_reg(serial, 0x8 , 0); 166 /* modem control */ 167 priv->mcr = 0; 168 ark3116_write_reg(serial, UART_MCR, 0); 169 170 if (!(priv->irda)) { 171 ark3116_write_reg(serial, 0xb , 0); 172 } else { 173 ark3116_write_reg(serial, 0xb , 1); 174 ark3116_write_reg(serial, 0xc , 0); 175 ark3116_write_reg(serial, 0xd , 0x41); 176 ark3116_write_reg(serial, 0xa , 1); 177 } 178 179 /* setup baudrate */ 180 ark3116_write_reg(serial, UART_LCR, UART_LCR_DLAB); 181 182 /* setup for 9600 8N1 */ 183 priv->quot = calc_divisor(9600); 184 ark3116_write_reg(serial, UART_DLL, priv->quot & 0xff); 185 ark3116_write_reg(serial, UART_DLM, (priv->quot>>8) & 0xff); 186 187 priv->lcr = UART_LCR_WLEN8; 188 ark3116_write_reg(serial, UART_LCR, UART_LCR_WLEN8); 189 190 ark3116_write_reg(serial, 0xe, 0); 191 192 if (priv->irda) 193 ark3116_write_reg(serial, 0x9, 0); 194 195 dev_info(&serial->dev->dev, 196 "%s using %s mode\n", 197 KBUILD_MODNAME, 198 priv->irda ? "IrDA" : "RS232"); 199 return 0; 200} 201 202static void ark3116_release(struct usb_serial *serial) 203{ 204 struct usb_serial_port *port = serial->port[0]; 205 struct ark3116_private *priv = usb_get_serial_port_data(port); 206 207 /* device is closed, so URBs and DMA should be down */ 208 209 usb_set_serial_port_data(port, NULL); 210 211 mutex_destroy(&priv->hw_lock); 212 213 kfree(priv); 214} 215 216static void ark3116_init_termios(struct tty_struct *tty) 217{ 218 struct ktermios *termios = tty->termios; 219 *termios = tty_std_termios; 220 termios->c_cflag = B9600 | CS8 221 | CREAD | HUPCL | CLOCAL; 222 termios->c_ispeed = 9600; 223 termios->c_ospeed = 9600; 224} 225 226static void ark3116_set_termios(struct tty_struct *tty, 227 struct usb_serial_port *port, 228 struct ktermios *old_termios) 229{ 230 struct usb_serial *serial = port->serial; 231 struct ark3116_private *priv = usb_get_serial_port_data(port); 232 struct ktermios *termios = tty->termios; 233 unsigned int cflag = termios->c_cflag; 234 int bps = tty_get_baud_rate(tty); 235 int quot; 236 __u8 lcr, hcr, eval; 237 238 /* set data bit count */ 239 switch (cflag & CSIZE) { 240 case CS5: 241 lcr = UART_LCR_WLEN5; 242 break; 243 case CS6: 244 lcr = UART_LCR_WLEN6; 245 break; 246 case CS7: 247 lcr = UART_LCR_WLEN7; 248 break; 249 default: 250 case CS8: 251 lcr = UART_LCR_WLEN8; 252 break; 253 } 254 if (cflag & CSTOPB) 255 lcr |= UART_LCR_STOP; 256 if (cflag & PARENB) 257 lcr |= UART_LCR_PARITY; 258 if (!(cflag & PARODD)) 259 lcr |= UART_LCR_EPAR; 260#ifdef CMSPAR 261 if (cflag & CMSPAR) 262 lcr |= UART_LCR_SPAR; 263#endif 264 /* handshake control */ 265 hcr = (cflag & CRTSCTS) ? 0x03 : 0x00; 266 267 /* calc baudrate */ 268 dbg("%s - setting bps to %d", __func__, bps); 269 eval = 0; 270 switch (bps) { 271 case 0: 272 quot = calc_divisor(9600); 273 break; 274 default: 275 if ((bps < 75) || (bps > 3000000)) 276 bps = 9600; 277 quot = calc_divisor(bps); 278 break; 279 case 460800: 280 eval = 1; 281 quot = calc_divisor(bps); 282 break; 283 case 921600: 284 eval = 2; 285 quot = calc_divisor(bps); 286 break; 287 } 288 289 /* Update state: synchronize */ 290 mutex_lock(&priv->hw_lock); 291 292 /* keep old LCR_SBC bit */ 293 lcr |= (priv->lcr & UART_LCR_SBC); 294 295 dbg("%s - setting hcr:0x%02x,lcr:0x%02x,quot:%d", 296 __func__, hcr, lcr, quot); 297 298 /* handshake control */ 299 if (priv->hcr != hcr) { 300 priv->hcr = hcr; 301 ark3116_write_reg(serial, 0x8, hcr); 302 } 303 304 /* baudrate */ 305 if (priv->quot != quot) { 306 priv->quot = quot; 307 priv->lcr = lcr; /* need to write lcr anyway */ 308 309 /* disable DMA since transmit/receive is 310 * shadowed by UART_DLL 311 */ 312 ark3116_write_reg(serial, UART_FCR, 0); 313 314 ark3116_write_reg(serial, UART_LCR, 315 lcr|UART_LCR_DLAB); 316 ark3116_write_reg(serial, UART_DLL, quot & 0xff); 317 ark3116_write_reg(serial, UART_DLM, (quot>>8) & 0xff); 318 319 /* restore lcr */ 320 ark3116_write_reg(serial, UART_LCR, lcr); 321 /* magic baudrate thingy: not sure what it does, 322 * but windows does this as well. 323 */ 324 ark3116_write_reg(serial, 0xe, eval); 325 326 /* enable DMA */ 327 ark3116_write_reg(serial, UART_FCR, UART_FCR_DMA_SELECT); 328 } else if (priv->lcr != lcr) { 329 priv->lcr = lcr; 330 ark3116_write_reg(serial, UART_LCR, lcr); 331 } 332 333 mutex_unlock(&priv->hw_lock); 334 335 /* check for software flow control */ 336 if (I_IXOFF(tty) || I_IXON(tty)) { 337 dev_warn(&serial->dev->dev, 338 "%s: don't know how to do software flow control\n", 339 KBUILD_MODNAME); 340 } 341 342 /* Don't rewrite B0 */ 343 if (tty_termios_baud_rate(termios)) 344 tty_termios_encode_baud_rate(termios, bps, bps); 345} 346 347static void ark3116_close(struct usb_serial_port *port) 348{ 349 struct usb_serial *serial = port->serial; 350 351 if (serial->dev) { 352 /* disable DMA */ 353 ark3116_write_reg(serial, UART_FCR, 0); 354 355 /* deactivate interrupts */ 356 ark3116_write_reg(serial, UART_IER, 0); 357 358 usb_serial_generic_close(port); 359 if (serial->num_interrupt_in) 360 usb_kill_urb(port->interrupt_in_urb); 361 } 362 363} 364 365static int ark3116_open(struct tty_struct *tty, struct usb_serial_port *port) 366{ 367 struct ark3116_private *priv = usb_get_serial_port_data(port); 368 struct usb_serial *serial = port->serial; 369 unsigned char *buf; 370 int result; 371 372 buf = kmalloc(1, GFP_KERNEL); 373 if (buf == NULL) 374 return -ENOMEM; 375 376 result = usb_serial_generic_open(tty, port); 377 if (result) { 378 dbg("%s - usb_serial_generic_open failed: %d", 379 __func__, result); 380 goto err_out; 381 } 382 383 /* remove any data still left: also clears error state */ 384 ark3116_read_reg(serial, UART_RX, buf); 385 386 /* read modem status */ 387 priv->msr = ark3116_read_reg(serial, UART_MSR, buf); 388 /* read line status */ 389 priv->lsr = ark3116_read_reg(serial, UART_LSR, buf); 390 391 result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL); 392 if (result) { 393 dev_err(&port->dev, "submit irq_in urb failed %d\n", 394 result); 395 ark3116_close(port); 396 goto err_out; 397 } 398 399 /* activate interrupts */ 400 ark3116_write_reg(port->serial, UART_IER, UART_IER_MSI|UART_IER_RLSI); 401 402 /* enable DMA */ 403 ark3116_write_reg(port->serial, UART_FCR, UART_FCR_DMA_SELECT); 404 405 /* setup termios */ 406 if (tty) 407 ark3116_set_termios(tty, port, NULL); 408 409err_out: 410 kfree(buf); 411 return result; 412} 413 414static int ark3116_get_icount(struct tty_struct *tty, 415 struct serial_icounter_struct *icount) 416{ 417 struct usb_serial_port *port = tty->driver_data; 418 struct ark3116_private *priv = usb_get_serial_port_data(port); 419 struct async_icount cnow = priv->icount; 420 icount->cts = cnow.cts; 421 icount->dsr = cnow.dsr; 422 icount->rng = cnow.rng; 423 icount->dcd = cnow.dcd; 424 icount->rx = cnow.rx; 425 icount->tx = cnow.tx; 426 icount->frame = cnow.frame; 427 icount->overrun = cnow.overrun; 428 icount->parity = cnow.parity; 429 icount->brk = cnow.brk; 430 icount->buf_overrun = cnow.buf_overrun; 431 return 0; 432} 433 434static int ark3116_ioctl(struct tty_struct *tty, 435 unsigned int cmd, unsigned long arg) 436{ 437 struct usb_serial_port *port = tty->driver_data; 438 struct ark3116_private *priv = usb_get_serial_port_data(port); 439 struct serial_struct serstruct; 440 void __user *user_arg = (void __user *)arg; 441 442 switch (cmd) { 443 case TIOCGSERIAL: 444 /* XXX: Some of these values are probably wrong. */ 445 memset(&serstruct, 0, sizeof(serstruct)); 446 serstruct.type = PORT_16654; 447 serstruct.line = port->serial->minor; 448 serstruct.port = port->number; 449 serstruct.custom_divisor = 0; 450 serstruct.baud_base = 460800; 451 452 if (copy_to_user(user_arg, &serstruct, sizeof(serstruct))) 453 return -EFAULT; 454 455 return 0; 456 case TIOCSSERIAL: 457 if (copy_from_user(&serstruct, user_arg, sizeof(serstruct))) 458 return -EFAULT; 459 return 0; 460 case TIOCMIWAIT: 461 for (;;) { 462 struct async_icount prev = priv->icount; 463 interruptible_sleep_on(&priv->delta_msr_wait); 464 /* see if a signal did it */ 465 if (signal_pending(current)) 466 return -ERESTARTSYS; 467 if ((prev.rng == priv->icount.rng) && 468 (prev.dsr == priv->icount.dsr) && 469 (prev.dcd == priv->icount.dcd) && 470 (prev.cts == priv->icount.cts)) 471 return -EIO; 472 if ((arg & TIOCM_RNG && 473 (prev.rng != priv->icount.rng)) || 474 (arg & TIOCM_DSR && 475 (prev.dsr != priv->icount.dsr)) || 476 (arg & TIOCM_CD && 477 (prev.dcd != priv->icount.dcd)) || 478 (arg & TIOCM_CTS && 479 (prev.cts != priv->icount.cts))) 480 return 0; 481 } 482 break; 483 } 484 485 return -ENOIOCTLCMD; 486} 487 488static int ark3116_tiocmget(struct tty_struct *tty) 489{ 490 struct usb_serial_port *port = tty->driver_data; 491 struct ark3116_private *priv = usb_get_serial_port_data(port); 492 __u32 status; 493 __u32 ctrl; 494 unsigned long flags; 495 496 mutex_lock(&priv->hw_lock); 497 ctrl = priv->mcr; 498 mutex_unlock(&priv->hw_lock); 499 500 spin_lock_irqsave(&priv->status_lock, flags); 501 status = priv->msr; 502 spin_unlock_irqrestore(&priv->status_lock, flags); 503 504 return (status & UART_MSR_DSR ? TIOCM_DSR : 0) | 505 (status & UART_MSR_CTS ? TIOCM_CTS : 0) | 506 (status & UART_MSR_RI ? TIOCM_RI : 0) | 507 (status & UART_MSR_DCD ? TIOCM_CD : 0) | 508 (ctrl & UART_MCR_DTR ? TIOCM_DTR : 0) | 509 (ctrl & UART_MCR_RTS ? TIOCM_RTS : 0) | 510 (ctrl & UART_MCR_OUT1 ? TIOCM_OUT1 : 0) | 511 (ctrl & UART_MCR_OUT2 ? TIOCM_OUT2 : 0); 512} 513 514static int ark3116_tiocmset(struct tty_struct *tty, 515 unsigned set, unsigned clr) 516{ 517 struct usb_serial_port *port = tty->driver_data; 518 struct ark3116_private *priv = usb_get_serial_port_data(port); 519 520 /* we need to take the mutex here, to make sure that the value 521 * in priv->mcr is actually the one that is in the hardware 522 */ 523 524 mutex_lock(&priv->hw_lock); 525 526 if (set & TIOCM_RTS) 527 priv->mcr |= UART_MCR_RTS; 528 if (set & TIOCM_DTR) 529 priv->mcr |= UART_MCR_DTR; 530 if (set & TIOCM_OUT1) 531 priv->mcr |= UART_MCR_OUT1; 532 if (set & TIOCM_OUT2) 533 priv->mcr |= UART_MCR_OUT2; 534 if (clr & TIOCM_RTS) 535 priv->mcr &= ~UART_MCR_RTS; 536 if (clr & TIOCM_DTR) 537 priv->mcr &= ~UART_MCR_DTR; 538 if (clr & TIOCM_OUT1) 539 priv->mcr &= ~UART_MCR_OUT1; 540 if (clr & TIOCM_OUT2) 541 priv->mcr &= ~UART_MCR_OUT2; 542 543 ark3116_write_reg(port->serial, UART_MCR, priv->mcr); 544 545 mutex_unlock(&priv->hw_lock); 546 547 return 0; 548} 549 550static void ark3116_break_ctl(struct tty_struct *tty, int break_state) 551{ 552 struct usb_serial_port *port = tty->driver_data; 553 struct ark3116_private *priv = usb_get_serial_port_data(port); 554 555 /* LCR is also used for other things: protect access */ 556 mutex_lock(&priv->hw_lock); 557 558 if (break_state) 559 priv->lcr |= UART_LCR_SBC; 560 else 561 priv->lcr &= ~UART_LCR_SBC; 562 563 ark3116_write_reg(port->serial, UART_LCR, priv->lcr); 564 565 mutex_unlock(&priv->hw_lock); 566} 567 568static void ark3116_update_msr(struct usb_serial_port *port, __u8 msr) 569{ 570 struct ark3116_private *priv = usb_get_serial_port_data(port); 571 unsigned long flags; 572 573 spin_lock_irqsave(&priv->status_lock, flags); 574 priv->msr = msr; 575 spin_unlock_irqrestore(&priv->status_lock, flags); 576 577 if (msr & UART_MSR_ANY_DELTA) { 578 /* update input line counters */ 579 if (msr & UART_MSR_DCTS) 580 priv->icount.cts++; 581 if (msr & UART_MSR_DDSR) 582 priv->icount.dsr++; 583 if (msr & UART_MSR_DDCD) 584 priv->icount.dcd++; 585 if (msr & UART_MSR_TERI) 586 priv->icount.rng++; 587 wake_up_interruptible(&priv->delta_msr_wait); 588 } 589} 590 591static void ark3116_update_lsr(struct usb_serial_port *port, __u8 lsr) 592{ 593 struct ark3116_private *priv = usb_get_serial_port_data(port); 594 unsigned long flags; 595 596 spin_lock_irqsave(&priv->status_lock, flags); 597 /* combine bits */ 598 priv->lsr |= lsr; 599 spin_unlock_irqrestore(&priv->status_lock, flags); 600 601 if (lsr&UART_LSR_BRK_ERROR_BITS) { 602 if (lsr & UART_LSR_BI) 603 priv->icount.brk++; 604 if (lsr & UART_LSR_FE) 605 priv->icount.frame++; 606 if (lsr & UART_LSR_PE) 607 priv->icount.parity++; 608 if (lsr & UART_LSR_OE) 609 priv->icount.overrun++; 610 } 611} 612 613static void ark3116_read_int_callback(struct urb *urb) 614{ 615 struct usb_serial_port *port = urb->context; 616 int status = urb->status; 617 const __u8 *data = urb->transfer_buffer; 618 int result; 619 620 switch (status) { 621 case -ECONNRESET: 622 case -ENOENT: 623 case -ESHUTDOWN: 624 /* this urb is terminated, clean up */ 625 dbg("%s - urb shutting down with status: %d", 626 __func__, status); 627 return; 628 default: 629 dbg("%s - nonzero urb status received: %d", 630 __func__, status); 631 break; 632 case 0: /* success */ 633 /* discovered this by trail and error... */ 634 if ((urb->actual_length == 4) && (data[0] == 0xe8)) { 635 const __u8 id = data[1]&UART_IIR_ID; 636 dbg("%s: iir=%02x", __func__, data[1]); 637 if (id == UART_IIR_MSI) { 638 dbg("%s: msr=%02x", __func__, data[3]); 639 ark3116_update_msr(port, data[3]); 640 break; 641 } else if (id == UART_IIR_RLSI) { 642 dbg("%s: lsr=%02x", __func__, data[2]); 643 ark3116_update_lsr(port, data[2]); 644 break; 645 } 646 } 647 /* 648 * Not sure what this data meant... 649 */ 650 usb_serial_debug_data(debug, &port->dev, 651 __func__, 652 urb->actual_length, 653 urb->transfer_buffer); 654 break; 655 } 656 657 result = usb_submit_urb(urb, GFP_ATOMIC); 658 if (result) 659 dev_err(&urb->dev->dev, 660 "%s - Error %d submitting interrupt urb\n", 661 __func__, result); 662} 663 664 665/* Data comes in via the bulk (data) URB, erors/interrupts via the int URB. 666 * This means that we cannot be sure which data byte has an associated error 667 * condition, so we report an error for all data in the next bulk read. 668 * 669 * Actually, there might even be a window between the bulk data leaving the 670 * ark and reading/resetting the lsr in the read_bulk_callback where an 671 * interrupt for the next data block could come in. 672 * Without somekind of ordering on the ark, we would have to report the 673 * error for the next block of data as well... 674 * For now, let's pretend this can't happen. 675 */ 676static void ark3116_process_read_urb(struct urb *urb) 677{ 678 struct usb_serial_port *port = urb->context; 679 struct ark3116_private *priv = usb_get_serial_port_data(port); 680 struct tty_struct *tty; 681 unsigned char *data = urb->transfer_buffer; 682 char tty_flag = TTY_NORMAL; 683 unsigned long flags; 684 __u32 lsr; 685 686 /* update line status */ 687 spin_lock_irqsave(&priv->status_lock, flags); 688 lsr = priv->lsr; 689 priv->lsr &= ~UART_LSR_BRK_ERROR_BITS; 690 spin_unlock_irqrestore(&priv->status_lock, flags); 691 692 if (!urb->actual_length) 693 return; 694 695 tty = tty_port_tty_get(&port->port); 696 if (!tty) 697 return; 698 699 if (lsr & UART_LSR_BRK_ERROR_BITS) { 700 if (lsr & UART_LSR_BI) 701 tty_flag = TTY_BREAK; 702 else if (lsr & UART_LSR_PE) 703 tty_flag = TTY_PARITY; 704 else if (lsr & UART_LSR_FE) 705 tty_flag = TTY_FRAME; 706 707 /* overrun is special, not associated with a char */ 708 if (lsr & UART_LSR_OE) 709 tty_insert_flip_char(tty, 0, TTY_OVERRUN); 710 } 711 tty_insert_flip_string_fixed_flag(tty, data, tty_flag, 712 urb->actual_length); 713 tty_flip_buffer_push(tty); 714 tty_kref_put(tty); 715} 716 717static struct usb_driver ark3116_driver = { 718 .name = "ark3116", 719 .probe = usb_serial_probe, 720 .disconnect = usb_serial_disconnect, 721 .id_table = id_table, 722}; 723 724static struct usb_serial_driver ark3116_device = { 725 .driver = { 726 .owner = THIS_MODULE, 727 .name = "ark3116", 728 }, 729 .id_table = id_table, 730 .num_ports = 1, 731 .attach = ark3116_attach, 732 .release = ark3116_release, 733 .set_termios = ark3116_set_termios, 734 .init_termios = ark3116_init_termios, 735 .ioctl = ark3116_ioctl, 736 .tiocmget = ark3116_tiocmget, 737 .tiocmset = ark3116_tiocmset, 738 .get_icount = ark3116_get_icount, 739 .open = ark3116_open, 740 .close = ark3116_close, 741 .break_ctl = ark3116_break_ctl, 742 .read_int_callback = ark3116_read_int_callback, 743 .process_read_urb = ark3116_process_read_urb, 744}; 745 746static struct usb_serial_driver * const serial_drivers[] = { 747 &ark3116_device, NULL 748}; 749 750module_usb_serial_driver(ark3116_driver, serial_drivers); 751 752MODULE_LICENSE("GPL"); 753 754MODULE_AUTHOR(DRIVER_AUTHOR); 755MODULE_DESCRIPTION(DRIVER_DESC); 756 757module_param(debug, bool, S_IRUGO | S_IWUSR); 758MODULE_PARM_DESC(debug, "Enable debug"); 759 760/* 761 * The following describes what I learned from studying the old 762 * ark3116.c driver, disassembling the windows driver, and some lucky 763 * guesses. Since I do not have any datasheet or other 764 * documentation, inaccuracies are almost guaranteed. 765 * 766 * Some specs for the ARK3116 can be found here: 767 * http://web.archive.org/web/20060318000438/ 768 * www.arkmicro.com/en/products/view.php?id=10 769 * On that page, 2 GPIO pins are mentioned: I assume these are the 770 * OUT1 and OUT2 pins of the UART, so I added support for those 771 * through the MCR. Since the pins are not available on my hardware, 772 * I could not verify this. 773 * Also, it states there is "on-chip hardware flow control". I have 774 * discovered how to enable that. Unfortunately, I do not know how to 775 * enable XON/XOFF (software) flow control, which would need support 776 * from the chip as well to work. Because of the wording on the web 777 * page there is a real possibility the chip simply does not support 778 * software flow control. 779 * 780 * I got my ark3116 as part of a mobile phone adapter cable. On the 781 * PCB, the following numbered contacts are present: 782 * 783 * 1:- +5V 784 * 2:o DTR 785 * 3:i RX 786 * 4:i DCD 787 * 5:o RTS 788 * 6:o TX 789 * 7:i RI 790 * 8:i DSR 791 * 10:- 0V 792 * 11:i CTS 793 * 794 * On my chip, all signals seem to be 3.3V, but 5V tolerant. But that 795 * may be different for the one you have ;-). 796 * 797 * The windows driver limits the registers to 0-F, so I assume there 798 * are actually 16 present on the device. 799 * 800 * On an UART interrupt, 4 bytes of data come in on the interrupt 801 * endpoint. The bytes are 0xe8 IIR LSR MSR. 802 * 803 * The baudrate seems to be generated from the 12MHz crystal, using 804 * 4-times subsampling. So quot=12e6/(4*baud). Also see description 805 * of register E. 806 * 807 * Registers 0-7: 808 * These seem to be the same as for a regular 16450. The FCR is set 809 * to UART_FCR_DMA_SELECT (0x8), I guess to enable transfers between 810 * the UART and the USB bridge/DMA engine. 811 * 812 * Register 8: 813 * By trial and error, I found out that bit 0 enables hardware CTS, 814 * stopping TX when CTS is +5V. Bit 1 does the same for RTS, making 815 * RTS +5V when the 3116 cannot transfer the data to the USB bus 816 * (verified by disabling the reading URB). Note that as far as I can 817 * tell, the windows driver does NOT use this, so there might be some 818 * hardware bug or something. 819 * 820 * According to a patch provided here 821 * (http://lkml.org/lkml/2009/7/26/56), the ARK3116 can also be used 822 * as an IrDA dongle. Since I do not have such a thing, I could not 823 * investigate that aspect. However, I can speculate ;-). 824 * 825 * - IrDA encodes data differently than RS232. Most likely, one of 826 * the bits in registers 9..E enables the IR ENDEC (encoder/decoder). 827 * - Depending on the IR transceiver, the input and output need to be 828 * inverted, so there are probably bits for that as well. 829 * - IrDA is half-duplex, so there should be a bit for selecting that. 830 * 831 * This still leaves at least two registers unaccounted for. Perhaps 832 * The chip can do XON/XOFF or CRC in HW? 833 * 834 * Register 9: 835 * Set to 0x00 for IrDA, when the baudrate is initialised. 836 * 837 * Register A: 838 * Set to 0x01 for IrDA, at init. 839 * 840 * Register B: 841 * Set to 0x01 for IrDA, 0x00 for RS232, at init. 842 * 843 * Register C: 844 * Set to 00 for IrDA, at init. 845 * 846 * Register D: 847 * Set to 0x41 for IrDA, at init. 848 * 849 * Register E: 850 * Somekind of baudrate override. The windows driver seems to set 851 * this to 0x00 for normal baudrates, 0x01 for 460800, 0x02 for 921600. 852 * Since 460800 and 921600 cannot be obtained by dividing 3MHz by an integer, 853 * it could be somekind of subdivisor thingy. 854 * However,it does not seem to do anything: selecting 921600 (divisor 3, 855 * reg E=2), still gets 1 MHz. I also checked if registers 9, C or F would 856 * work, but they don't. 857 * 858 * Register F: unknown 859 */ 860