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 40 /* 41 * Version information 42 */ 43 44 #define DRIVER_VERSION "v0.7" 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 const 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 dev_dbg(&port->dev, "%s - setting bps to %d\n", __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 dev_dbg(&port->dev, "%s - setting hcr:0x%02x,lcr:0x%02x,quot:%d\n", 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 usb_serial_generic_close(port); 358 if (serial->num_interrupt_in) 359 usb_kill_urb(port->interrupt_in_urb); 360 } 361 362 } 363 364 static int ark3116_open(struct tty_struct *tty, struct usb_serial_port *port) 365 { 366 struct ark3116_private *priv = usb_get_serial_port_data(port); 367 struct usb_serial *serial = port->serial; 368 unsigned char *buf; 369 int result; 370 371 buf = kmalloc(1, GFP_KERNEL); 372 if (buf == NULL) 373 return -ENOMEM; 374 375 result = usb_serial_generic_open(tty, port); 376 if (result) { 377 dev_dbg(&port->dev, 378 "%s - usb_serial_generic_open failed: %d\n", 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); 408 409 err_out: 410 kfree(buf); 411 return result; 412 } 413 414 static 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 } 433 434 static 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 } 487 488 static 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 } 513 514 static 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 } 549 550 static 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 } 567 568 static 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 } 590 591 static 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 } 612 613 static 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 dev_dbg(&port->dev, "%s - urb shutting down with status: %d\n", 626 __func__, status); 627 return; 628 default: 629 dev_dbg(&port->dev, "%s - nonzero urb status received: %d\n", 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 dev_dbg(&port->dev, "%s: iir=%02x\n", __func__, data[1]); 637 if (id == UART_IIR_MSI) { 638 dev_dbg(&port->dev, "%s: msr=%02x\n", 639 __func__, data[3]); 640 ark3116_update_msr(port, data[3]); 641 break; 642 } else if (id == UART_IIR_RLSI) { 643 dev_dbg(&port->dev, "%s: lsr=%02x\n", 644 __func__, data[2]); 645 ark3116_update_lsr(port, data[2]); 646 break; 647 } 648 } 649 /* 650 * Not sure what this data meant... 651 */ 652 usb_serial_debug_data(&port->dev, __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 static void ark3116_process_read_urb(struct urb *urb) 678 { 679 struct usb_serial_port *port = urb->context; 680 struct ark3116_private *priv = usb_get_serial_port_data(port); 681 struct tty_struct *tty; 682 unsigned char *data = urb->transfer_buffer; 683 char tty_flag = TTY_NORMAL; 684 unsigned long flags; 685 __u32 lsr; 686 687 /* update line status */ 688 spin_lock_irqsave(&priv->status_lock, flags); 689 lsr = priv->lsr; 690 priv->lsr &= ~UART_LSR_BRK_ERROR_BITS; 691 spin_unlock_irqrestore(&priv->status_lock, flags); 692 693 if (!urb->actual_length) 694 return; 695 696 tty = tty_port_tty_get(&port->port); 697 if (!tty) 698 return; 699 700 if (lsr & UART_LSR_BRK_ERROR_BITS) { 701 if (lsr & UART_LSR_BI) 702 tty_flag = TTY_BREAK; 703 else if (lsr & UART_LSR_PE) 704 tty_flag = TTY_PARITY; 705 else if (lsr & UART_LSR_FE) 706 tty_flag = TTY_FRAME; 707 708 /* overrun is special, not associated with a char */ 709 if (lsr & UART_LSR_OE) 710 tty_insert_flip_char(tty, 0, TTY_OVERRUN); 711 } 712 tty_insert_flip_string_fixed_flag(tty, data, tty_flag, 713 urb->actual_length); 714 tty_flip_buffer_push(tty); 715 tty_kref_put(tty); 716 } 717 718 static struct usb_serial_driver ark3116_device = { 719 .driver = { 720 .owner = THIS_MODULE, 721 .name = "ark3116", 722 }, 723 .id_table = id_table, 724 .num_ports = 1, 725 .attach = ark3116_attach, 726 .release = ark3116_release, 727 .set_termios = ark3116_set_termios, 728 .init_termios = ark3116_init_termios, 729 .ioctl = ark3116_ioctl, 730 .tiocmget = ark3116_tiocmget, 731 .tiocmset = ark3116_tiocmset, 732 .get_icount = ark3116_get_icount, 733 .open = ark3116_open, 734 .close = ark3116_close, 735 .break_ctl = ark3116_break_ctl, 736 .read_int_callback = ark3116_read_int_callback, 737 .process_read_urb = ark3116_process_read_urb, 738 }; 739 740 static struct usb_serial_driver * const serial_drivers[] = { 741 &ark3116_device, NULL 742 }; 743 744 module_usb_serial_driver(serial_drivers, id_table); 745 746 MODULE_LICENSE("GPL"); 747 748 MODULE_AUTHOR(DRIVER_AUTHOR); 749 MODULE_DESCRIPTION(DRIVER_DESC); 750 751 /* 752 * The following describes what I learned from studying the old 753 * ark3116.c driver, disassembling the windows driver, and some lucky 754 * guesses. Since I do not have any datasheet or other 755 * documentation, inaccuracies are almost guaranteed. 756 * 757 * Some specs for the ARK3116 can be found here: 758 * http://web.archive.org/web/20060318000438/ 759 * www.arkmicro.com/en/products/view.php?id=10 760 * On that page, 2 GPIO pins are mentioned: I assume these are the 761 * OUT1 and OUT2 pins of the UART, so I added support for those 762 * through the MCR. Since the pins are not available on my hardware, 763 * I could not verify this. 764 * Also, it states there is "on-chip hardware flow control". I have 765 * discovered how to enable that. Unfortunately, I do not know how to 766 * enable XON/XOFF (software) flow control, which would need support 767 * from the chip as well to work. Because of the wording on the web 768 * page there is a real possibility the chip simply does not support 769 * software flow control. 770 * 771 * I got my ark3116 as part of a mobile phone adapter cable. On the 772 * PCB, the following numbered contacts are present: 773 * 774 * 1:- +5V 775 * 2:o DTR 776 * 3:i RX 777 * 4:i DCD 778 * 5:o RTS 779 * 6:o TX 780 * 7:i RI 781 * 8:i DSR 782 * 10:- 0V 783 * 11:i CTS 784 * 785 * On my chip, all signals seem to be 3.3V, but 5V tolerant. But that 786 * may be different for the one you have ;-). 787 * 788 * The windows driver limits the registers to 0-F, so I assume there 789 * are actually 16 present on the device. 790 * 791 * On an UART interrupt, 4 bytes of data come in on the interrupt 792 * endpoint. The bytes are 0xe8 IIR LSR MSR. 793 * 794 * The baudrate seems to be generated from the 12MHz crystal, using 795 * 4-times subsampling. So quot=12e6/(4*baud). Also see description 796 * of register E. 797 * 798 * Registers 0-7: 799 * These seem to be the same as for a regular 16450. The FCR is set 800 * to UART_FCR_DMA_SELECT (0x8), I guess to enable transfers between 801 * the UART and the USB bridge/DMA engine. 802 * 803 * Register 8: 804 * By trial and error, I found out that bit 0 enables hardware CTS, 805 * stopping TX when CTS is +5V. Bit 1 does the same for RTS, making 806 * RTS +5V when the 3116 cannot transfer the data to the USB bus 807 * (verified by disabling the reading URB). Note that as far as I can 808 * tell, the windows driver does NOT use this, so there might be some 809 * hardware bug or something. 810 * 811 * According to a patch provided here 812 * (http://lkml.org/lkml/2009/7/26/56), the ARK3116 can also be used 813 * as an IrDA dongle. Since I do not have such a thing, I could not 814 * investigate that aspect. However, I can speculate ;-). 815 * 816 * - IrDA encodes data differently than RS232. Most likely, one of 817 * the bits in registers 9..E enables the IR ENDEC (encoder/decoder). 818 * - Depending on the IR transceiver, the input and output need to be 819 * inverted, so there are probably bits for that as well. 820 * - IrDA is half-duplex, so there should be a bit for selecting that. 821 * 822 * This still leaves at least two registers unaccounted for. Perhaps 823 * The chip can do XON/XOFF or CRC in HW? 824 * 825 * Register 9: 826 * Set to 0x00 for IrDA, when the baudrate is initialised. 827 * 828 * Register A: 829 * Set to 0x01 for IrDA, at init. 830 * 831 * Register B: 832 * Set to 0x01 for IrDA, 0x00 for RS232, at init. 833 * 834 * Register C: 835 * Set to 00 for IrDA, at init. 836 * 837 * Register D: 838 * Set to 0x41 for IrDA, at init. 839 * 840 * Register E: 841 * Somekind of baudrate override. The windows driver seems to set 842 * this to 0x00 for normal baudrates, 0x01 for 460800, 0x02 for 921600. 843 * Since 460800 and 921600 cannot be obtained by dividing 3MHz by an integer, 844 * it could be somekind of subdivisor thingy. 845 * However,it does not seem to do anything: selecting 921600 (divisor 3, 846 * reg E=2), still gets 1 MHz. I also checked if registers 9, C or F would 847 * work, but they don't. 848 * 849 * Register F: unknown 850 */ 851