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 #define DRIVER_AUTHOR "Bart Hartgers <bart.hartgers+ark3116@gmail.com>" 41 #define DRIVER_DESC "USB ARK3116 serial/IrDA driver" 42 #define DRIVER_DEV_DESC "ARK3116 RS232/IrDA" 43 #define DRIVER_NAME "ark3116" 44 45 /* usb timeout of 1 second */ 46 #define ARK_TIMEOUT (1*HZ) 47 48 static const struct usb_device_id id_table[] = { 49 { USB_DEVICE(0x6547, 0x0232) }, 50 { USB_DEVICE(0x18ec, 0x3118) }, /* USB to IrDA adapter */ 51 { }, 52 }; 53 MODULE_DEVICE_TABLE(usb, id_table); 54 55 static int is_irda(struct usb_serial *serial) 56 { 57 struct usb_device *dev = serial->dev; 58 if (le16_to_cpu(dev->descriptor.idVendor) == 0x18ec && 59 le16_to_cpu(dev->descriptor.idProduct) == 0x3118) 60 return 1; 61 return 0; 62 } 63 64 struct ark3116_private { 65 wait_queue_head_t delta_msr_wait; 66 struct async_icount icount; 67 int irda; /* 1 for irda device */ 68 69 /* protects hw register updates */ 70 struct mutex hw_lock; 71 72 int quot; /* baudrate divisor */ 73 __u32 lcr; /* line control register value */ 74 __u32 hcr; /* handshake control register (0x8) 75 * value */ 76 __u32 mcr; /* modem contol register value */ 77 78 /* protects the status values below */ 79 spinlock_t status_lock; 80 __u32 msr; /* modem status register value */ 81 __u32 lsr; /* line status register value */ 82 }; 83 84 static int ark3116_write_reg(struct usb_serial *serial, 85 unsigned reg, __u8 val) 86 { 87 int result; 88 /* 0xfe 0x40 are magic values taken from original driver */ 89 result = usb_control_msg(serial->dev, 90 usb_sndctrlpipe(serial->dev, 0), 91 0xfe, 0x40, val, reg, 92 NULL, 0, ARK_TIMEOUT); 93 return result; 94 } 95 96 static int ark3116_read_reg(struct usb_serial *serial, 97 unsigned reg, unsigned char *buf) 98 { 99 int result; 100 /* 0xfe 0xc0 are magic values taken from original driver */ 101 result = usb_control_msg(serial->dev, 102 usb_rcvctrlpipe(serial->dev, 0), 103 0xfe, 0xc0, 0, reg, 104 buf, 1, ARK_TIMEOUT); 105 if (result < 0) 106 return result; 107 else 108 return buf[0]; 109 } 110 111 static inline int calc_divisor(int bps) 112 { 113 /* Original ark3116 made some exceptions in rounding here 114 * because windows did the same. Assume that is not really 115 * necessary. 116 * Crystal is 12MHz, probably because of USB, but we divide by 4? 117 */ 118 return (12000000 + 2*bps) / (4*bps); 119 } 120 121 static int ark3116_attach(struct usb_serial *serial) 122 { 123 /* make sure we have our end-points */ 124 if ((serial->num_bulk_in == 0) || 125 (serial->num_bulk_out == 0) || 126 (serial->num_interrupt_in == 0)) { 127 dev_err(&serial->dev->dev, 128 "%s - missing endpoint - " 129 "bulk in: %d, bulk out: %d, int in %d\n", 130 KBUILD_MODNAME, 131 serial->num_bulk_in, 132 serial->num_bulk_out, 133 serial->num_interrupt_in); 134 return -EINVAL; 135 } 136 137 return 0; 138 } 139 140 static int ark3116_port_probe(struct usb_serial_port *port) 141 { 142 struct usb_serial *serial = port->serial; 143 struct ark3116_private *priv; 144 145 priv = kzalloc(sizeof(*priv), GFP_KERNEL); 146 if (!priv) 147 return -ENOMEM; 148 149 init_waitqueue_head(&priv->delta_msr_wait); 150 mutex_init(&priv->hw_lock); 151 spin_lock_init(&priv->status_lock); 152 153 priv->irda = is_irda(serial); 154 155 usb_set_serial_port_data(port, priv); 156 157 /* setup the hardware */ 158 ark3116_write_reg(serial, UART_IER, 0); 159 /* disable DMA */ 160 ark3116_write_reg(serial, UART_FCR, 0); 161 /* handshake control */ 162 priv->hcr = 0; 163 ark3116_write_reg(serial, 0x8 , 0); 164 /* modem control */ 165 priv->mcr = 0; 166 ark3116_write_reg(serial, UART_MCR, 0); 167 168 if (!(priv->irda)) { 169 ark3116_write_reg(serial, 0xb , 0); 170 } else { 171 ark3116_write_reg(serial, 0xb , 1); 172 ark3116_write_reg(serial, 0xc , 0); 173 ark3116_write_reg(serial, 0xd , 0x41); 174 ark3116_write_reg(serial, 0xa , 1); 175 } 176 177 /* setup baudrate */ 178 ark3116_write_reg(serial, UART_LCR, UART_LCR_DLAB); 179 180 /* setup for 9600 8N1 */ 181 priv->quot = calc_divisor(9600); 182 ark3116_write_reg(serial, UART_DLL, priv->quot & 0xff); 183 ark3116_write_reg(serial, UART_DLM, (priv->quot>>8) & 0xff); 184 185 priv->lcr = UART_LCR_WLEN8; 186 ark3116_write_reg(serial, UART_LCR, UART_LCR_WLEN8); 187 188 ark3116_write_reg(serial, 0xe, 0); 189 190 if (priv->irda) 191 ark3116_write_reg(serial, 0x9, 0); 192 193 dev_info(&serial->dev->dev, 194 "%s using %s mode\n", 195 KBUILD_MODNAME, 196 priv->irda ? "IrDA" : "RS232"); 197 return 0; 198 } 199 200 static int ark3116_port_remove(struct usb_serial_port *port) 201 { 202 struct ark3116_private *priv = usb_get_serial_port_data(port); 203 204 /* device is closed, so URBs and DMA should be down */ 205 mutex_destroy(&priv->hw_lock); 206 kfree(priv); 207 208 return 0; 209 } 210 211 static void ark3116_init_termios(struct tty_struct *tty) 212 { 213 struct ktermios *termios = &tty->termios; 214 *termios = tty_std_termios; 215 termios->c_cflag = B9600 | CS8 216 | CREAD | HUPCL | CLOCAL; 217 termios->c_ispeed = 9600; 218 termios->c_ospeed = 9600; 219 } 220 221 static void ark3116_set_termios(struct tty_struct *tty, 222 struct usb_serial_port *port, 223 struct ktermios *old_termios) 224 { 225 struct usb_serial *serial = port->serial; 226 struct ark3116_private *priv = usb_get_serial_port_data(port); 227 struct ktermios *termios = &tty->termios; 228 unsigned int cflag = termios->c_cflag; 229 int bps = tty_get_baud_rate(tty); 230 int quot; 231 __u8 lcr, hcr, eval; 232 233 /* set data bit count */ 234 switch (cflag & CSIZE) { 235 case CS5: 236 lcr = UART_LCR_WLEN5; 237 break; 238 case CS6: 239 lcr = UART_LCR_WLEN6; 240 break; 241 case CS7: 242 lcr = UART_LCR_WLEN7; 243 break; 244 default: 245 case CS8: 246 lcr = UART_LCR_WLEN8; 247 break; 248 } 249 if (cflag & CSTOPB) 250 lcr |= UART_LCR_STOP; 251 if (cflag & PARENB) 252 lcr |= UART_LCR_PARITY; 253 if (!(cflag & PARODD)) 254 lcr |= UART_LCR_EPAR; 255 #ifdef CMSPAR 256 if (cflag & CMSPAR) 257 lcr |= UART_LCR_SPAR; 258 #endif 259 /* handshake control */ 260 hcr = (cflag & CRTSCTS) ? 0x03 : 0x00; 261 262 /* calc baudrate */ 263 dev_dbg(&port->dev, "%s - setting bps to %d\n", __func__, bps); 264 eval = 0; 265 switch (bps) { 266 case 0: 267 quot = calc_divisor(9600); 268 break; 269 default: 270 if ((bps < 75) || (bps > 3000000)) 271 bps = 9600; 272 quot = calc_divisor(bps); 273 break; 274 case 460800: 275 eval = 1; 276 quot = calc_divisor(bps); 277 break; 278 case 921600: 279 eval = 2; 280 quot = calc_divisor(bps); 281 break; 282 } 283 284 /* Update state: synchronize */ 285 mutex_lock(&priv->hw_lock); 286 287 /* keep old LCR_SBC bit */ 288 lcr |= (priv->lcr & UART_LCR_SBC); 289 290 dev_dbg(&port->dev, "%s - setting hcr:0x%02x,lcr:0x%02x,quot:%d\n", 291 __func__, hcr, lcr, quot); 292 293 /* handshake control */ 294 if (priv->hcr != hcr) { 295 priv->hcr = hcr; 296 ark3116_write_reg(serial, 0x8, hcr); 297 } 298 299 /* baudrate */ 300 if (priv->quot != quot) { 301 priv->quot = quot; 302 priv->lcr = lcr; /* need to write lcr anyway */ 303 304 /* disable DMA since transmit/receive is 305 * shadowed by UART_DLL 306 */ 307 ark3116_write_reg(serial, UART_FCR, 0); 308 309 ark3116_write_reg(serial, UART_LCR, 310 lcr|UART_LCR_DLAB); 311 ark3116_write_reg(serial, UART_DLL, quot & 0xff); 312 ark3116_write_reg(serial, UART_DLM, (quot>>8) & 0xff); 313 314 /* restore lcr */ 315 ark3116_write_reg(serial, UART_LCR, lcr); 316 /* magic baudrate thingy: not sure what it does, 317 * but windows does this as well. 318 */ 319 ark3116_write_reg(serial, 0xe, eval); 320 321 /* enable DMA */ 322 ark3116_write_reg(serial, UART_FCR, UART_FCR_DMA_SELECT); 323 } else if (priv->lcr != lcr) { 324 priv->lcr = lcr; 325 ark3116_write_reg(serial, UART_LCR, lcr); 326 } 327 328 mutex_unlock(&priv->hw_lock); 329 330 /* check for software flow control */ 331 if (I_IXOFF(tty) || I_IXON(tty)) { 332 dev_warn(&serial->dev->dev, 333 "%s: don't know how to do software flow control\n", 334 KBUILD_MODNAME); 335 } 336 337 /* Don't rewrite B0 */ 338 if (tty_termios_baud_rate(termios)) 339 tty_termios_encode_baud_rate(termios, bps, bps); 340 } 341 342 static void ark3116_close(struct usb_serial_port *port) 343 { 344 struct usb_serial *serial = port->serial; 345 346 if (serial->dev) { 347 /* disable DMA */ 348 ark3116_write_reg(serial, UART_FCR, 0); 349 350 /* deactivate interrupts */ 351 ark3116_write_reg(serial, UART_IER, 0); 352 353 usb_serial_generic_close(port); 354 if (serial->num_interrupt_in) 355 usb_kill_urb(port->interrupt_in_urb); 356 } 357 358 } 359 360 static int ark3116_open(struct tty_struct *tty, struct usb_serial_port *port) 361 { 362 struct ark3116_private *priv = usb_get_serial_port_data(port); 363 struct usb_serial *serial = port->serial; 364 unsigned char *buf; 365 int result; 366 367 buf = kmalloc(1, GFP_KERNEL); 368 if (buf == NULL) 369 return -ENOMEM; 370 371 result = usb_serial_generic_open(tty, port); 372 if (result) { 373 dev_dbg(&port->dev, 374 "%s - usb_serial_generic_open failed: %d\n", 375 __func__, result); 376 goto err_out; 377 } 378 379 /* remove any data still left: also clears error state */ 380 ark3116_read_reg(serial, UART_RX, buf); 381 382 /* read modem status */ 383 priv->msr = ark3116_read_reg(serial, UART_MSR, buf); 384 /* read line status */ 385 priv->lsr = ark3116_read_reg(serial, UART_LSR, buf); 386 387 result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL); 388 if (result) { 389 dev_err(&port->dev, "submit irq_in urb failed %d\n", 390 result); 391 ark3116_close(port); 392 goto err_out; 393 } 394 395 /* activate interrupts */ 396 ark3116_write_reg(port->serial, UART_IER, UART_IER_MSI|UART_IER_RLSI); 397 398 /* enable DMA */ 399 ark3116_write_reg(port->serial, UART_FCR, UART_FCR_DMA_SELECT); 400 401 /* setup termios */ 402 if (tty) 403 ark3116_set_termios(tty, port, NULL); 404 405 err_out: 406 kfree(buf); 407 return result; 408 } 409 410 static int ark3116_get_icount(struct tty_struct *tty, 411 struct serial_icounter_struct *icount) 412 { 413 struct usb_serial_port *port = tty->driver_data; 414 struct ark3116_private *priv = usb_get_serial_port_data(port); 415 struct async_icount cnow = priv->icount; 416 icount->cts = cnow.cts; 417 icount->dsr = cnow.dsr; 418 icount->rng = cnow.rng; 419 icount->dcd = cnow.dcd; 420 icount->rx = cnow.rx; 421 icount->tx = cnow.tx; 422 icount->frame = cnow.frame; 423 icount->overrun = cnow.overrun; 424 icount->parity = cnow.parity; 425 icount->brk = cnow.brk; 426 icount->buf_overrun = cnow.buf_overrun; 427 return 0; 428 } 429 430 static int ark3116_ioctl(struct tty_struct *tty, 431 unsigned int cmd, unsigned long arg) 432 { 433 struct usb_serial_port *port = tty->driver_data; 434 struct ark3116_private *priv = usb_get_serial_port_data(port); 435 struct serial_struct serstruct; 436 void __user *user_arg = (void __user *)arg; 437 438 switch (cmd) { 439 case TIOCGSERIAL: 440 /* XXX: Some of these values are probably wrong. */ 441 memset(&serstruct, 0, sizeof(serstruct)); 442 serstruct.type = PORT_16654; 443 serstruct.line = port->serial->minor; 444 serstruct.port = port->number; 445 serstruct.custom_divisor = 0; 446 serstruct.baud_base = 460800; 447 448 if (copy_to_user(user_arg, &serstruct, sizeof(serstruct))) 449 return -EFAULT; 450 451 return 0; 452 case TIOCSSERIAL: 453 if (copy_from_user(&serstruct, user_arg, sizeof(serstruct))) 454 return -EFAULT; 455 return 0; 456 case TIOCMIWAIT: 457 for (;;) { 458 struct async_icount prev = priv->icount; 459 interruptible_sleep_on(&priv->delta_msr_wait); 460 /* see if a signal did it */ 461 if (signal_pending(current)) 462 return -ERESTARTSYS; 463 if ((prev.rng == priv->icount.rng) && 464 (prev.dsr == priv->icount.dsr) && 465 (prev.dcd == priv->icount.dcd) && 466 (prev.cts == priv->icount.cts)) 467 return -EIO; 468 if ((arg & TIOCM_RNG && 469 (prev.rng != priv->icount.rng)) || 470 (arg & TIOCM_DSR && 471 (prev.dsr != priv->icount.dsr)) || 472 (arg & TIOCM_CD && 473 (prev.dcd != priv->icount.dcd)) || 474 (arg & TIOCM_CTS && 475 (prev.cts != priv->icount.cts))) 476 return 0; 477 } 478 break; 479 } 480 481 return -ENOIOCTLCMD; 482 } 483 484 static int ark3116_tiocmget(struct tty_struct *tty) 485 { 486 struct usb_serial_port *port = tty->driver_data; 487 struct ark3116_private *priv = usb_get_serial_port_data(port); 488 __u32 status; 489 __u32 ctrl; 490 unsigned long flags; 491 492 mutex_lock(&priv->hw_lock); 493 ctrl = priv->mcr; 494 mutex_unlock(&priv->hw_lock); 495 496 spin_lock_irqsave(&priv->status_lock, flags); 497 status = priv->msr; 498 spin_unlock_irqrestore(&priv->status_lock, flags); 499 500 return (status & UART_MSR_DSR ? TIOCM_DSR : 0) | 501 (status & UART_MSR_CTS ? TIOCM_CTS : 0) | 502 (status & UART_MSR_RI ? TIOCM_RI : 0) | 503 (status & UART_MSR_DCD ? TIOCM_CD : 0) | 504 (ctrl & UART_MCR_DTR ? TIOCM_DTR : 0) | 505 (ctrl & UART_MCR_RTS ? TIOCM_RTS : 0) | 506 (ctrl & UART_MCR_OUT1 ? TIOCM_OUT1 : 0) | 507 (ctrl & UART_MCR_OUT2 ? TIOCM_OUT2 : 0); 508 } 509 510 static int ark3116_tiocmset(struct tty_struct *tty, 511 unsigned set, unsigned clr) 512 { 513 struct usb_serial_port *port = tty->driver_data; 514 struct ark3116_private *priv = usb_get_serial_port_data(port); 515 516 /* we need to take the mutex here, to make sure that the value 517 * in priv->mcr is actually the one that is in the hardware 518 */ 519 520 mutex_lock(&priv->hw_lock); 521 522 if (set & TIOCM_RTS) 523 priv->mcr |= UART_MCR_RTS; 524 if (set & TIOCM_DTR) 525 priv->mcr |= UART_MCR_DTR; 526 if (set & TIOCM_OUT1) 527 priv->mcr |= UART_MCR_OUT1; 528 if (set & TIOCM_OUT2) 529 priv->mcr |= UART_MCR_OUT2; 530 if (clr & TIOCM_RTS) 531 priv->mcr &= ~UART_MCR_RTS; 532 if (clr & TIOCM_DTR) 533 priv->mcr &= ~UART_MCR_DTR; 534 if (clr & TIOCM_OUT1) 535 priv->mcr &= ~UART_MCR_OUT1; 536 if (clr & TIOCM_OUT2) 537 priv->mcr &= ~UART_MCR_OUT2; 538 539 ark3116_write_reg(port->serial, UART_MCR, priv->mcr); 540 541 mutex_unlock(&priv->hw_lock); 542 543 return 0; 544 } 545 546 static void ark3116_break_ctl(struct tty_struct *tty, int break_state) 547 { 548 struct usb_serial_port *port = tty->driver_data; 549 struct ark3116_private *priv = usb_get_serial_port_data(port); 550 551 /* LCR is also used for other things: protect access */ 552 mutex_lock(&priv->hw_lock); 553 554 if (break_state) 555 priv->lcr |= UART_LCR_SBC; 556 else 557 priv->lcr &= ~UART_LCR_SBC; 558 559 ark3116_write_reg(port->serial, UART_LCR, priv->lcr); 560 561 mutex_unlock(&priv->hw_lock); 562 } 563 564 static void ark3116_update_msr(struct usb_serial_port *port, __u8 msr) 565 { 566 struct ark3116_private *priv = usb_get_serial_port_data(port); 567 unsigned long flags; 568 569 spin_lock_irqsave(&priv->status_lock, flags); 570 priv->msr = msr; 571 spin_unlock_irqrestore(&priv->status_lock, flags); 572 573 if (msr & UART_MSR_ANY_DELTA) { 574 /* update input line counters */ 575 if (msr & UART_MSR_DCTS) 576 priv->icount.cts++; 577 if (msr & UART_MSR_DDSR) 578 priv->icount.dsr++; 579 if (msr & UART_MSR_DDCD) 580 priv->icount.dcd++; 581 if (msr & UART_MSR_TERI) 582 priv->icount.rng++; 583 wake_up_interruptible(&priv->delta_msr_wait); 584 } 585 } 586 587 static void ark3116_update_lsr(struct usb_serial_port *port, __u8 lsr) 588 { 589 struct ark3116_private *priv = usb_get_serial_port_data(port); 590 unsigned long flags; 591 592 spin_lock_irqsave(&priv->status_lock, flags); 593 /* combine bits */ 594 priv->lsr |= lsr; 595 spin_unlock_irqrestore(&priv->status_lock, flags); 596 597 if (lsr&UART_LSR_BRK_ERROR_BITS) { 598 if (lsr & UART_LSR_BI) 599 priv->icount.brk++; 600 if (lsr & UART_LSR_FE) 601 priv->icount.frame++; 602 if (lsr & UART_LSR_PE) 603 priv->icount.parity++; 604 if (lsr & UART_LSR_OE) 605 priv->icount.overrun++; 606 } 607 } 608 609 static void ark3116_read_int_callback(struct urb *urb) 610 { 611 struct usb_serial_port *port = urb->context; 612 int status = urb->status; 613 const __u8 *data = urb->transfer_buffer; 614 int result; 615 616 switch (status) { 617 case -ECONNRESET: 618 case -ENOENT: 619 case -ESHUTDOWN: 620 /* this urb is terminated, clean up */ 621 dev_dbg(&port->dev, "%s - urb shutting down with status: %d\n", 622 __func__, status); 623 return; 624 default: 625 dev_dbg(&port->dev, "%s - nonzero urb status received: %d\n", 626 __func__, status); 627 break; 628 case 0: /* success */ 629 /* discovered this by trail and error... */ 630 if ((urb->actual_length == 4) && (data[0] == 0xe8)) { 631 const __u8 id = data[1]&UART_IIR_ID; 632 dev_dbg(&port->dev, "%s: iir=%02x\n", __func__, data[1]); 633 if (id == UART_IIR_MSI) { 634 dev_dbg(&port->dev, "%s: msr=%02x\n", 635 __func__, data[3]); 636 ark3116_update_msr(port, data[3]); 637 break; 638 } else if (id == UART_IIR_RLSI) { 639 dev_dbg(&port->dev, "%s: lsr=%02x\n", 640 __func__, data[2]); 641 ark3116_update_lsr(port, data[2]); 642 break; 643 } 644 } 645 /* 646 * Not sure what this data meant... 647 */ 648 usb_serial_debug_data(&port->dev, __func__, 649 urb->actual_length, 650 urb->transfer_buffer); 651 break; 652 } 653 654 result = usb_submit_urb(urb, GFP_ATOMIC); 655 if (result) 656 dev_err(&urb->dev->dev, 657 "%s - Error %d submitting interrupt urb\n", 658 __func__, result); 659 } 660 661 662 /* Data comes in via the bulk (data) URB, erors/interrupts via the int URB. 663 * This means that we cannot be sure which data byte has an associated error 664 * condition, so we report an error for all data in the next bulk read. 665 * 666 * Actually, there might even be a window between the bulk data leaving the 667 * ark and reading/resetting the lsr in the read_bulk_callback where an 668 * interrupt for the next data block could come in. 669 * Without somekind of ordering on the ark, we would have to report the 670 * error for the next block of data as well... 671 * For now, let's pretend this can't happen. 672 */ 673 static void ark3116_process_read_urb(struct urb *urb) 674 { 675 struct usb_serial_port *port = urb->context; 676 struct ark3116_private *priv = usb_get_serial_port_data(port); 677 struct tty_struct *tty; 678 unsigned char *data = urb->transfer_buffer; 679 char tty_flag = TTY_NORMAL; 680 unsigned long flags; 681 __u32 lsr; 682 683 /* update line status */ 684 spin_lock_irqsave(&priv->status_lock, flags); 685 lsr = priv->lsr; 686 priv->lsr &= ~UART_LSR_BRK_ERROR_BITS; 687 spin_unlock_irqrestore(&priv->status_lock, flags); 688 689 if (!urb->actual_length) 690 return; 691 692 tty = tty_port_tty_get(&port->port); 693 if (!tty) 694 return; 695 696 if (lsr & UART_LSR_BRK_ERROR_BITS) { 697 if (lsr & UART_LSR_BI) 698 tty_flag = TTY_BREAK; 699 else if (lsr & UART_LSR_PE) 700 tty_flag = TTY_PARITY; 701 else if (lsr & UART_LSR_FE) 702 tty_flag = TTY_FRAME; 703 704 /* overrun is special, not associated with a char */ 705 if (lsr & UART_LSR_OE) 706 tty_insert_flip_char(tty, 0, TTY_OVERRUN); 707 } 708 tty_insert_flip_string_fixed_flag(tty, data, tty_flag, 709 urb->actual_length); 710 tty_flip_buffer_push(tty); 711 tty_kref_put(tty); 712 } 713 714 static struct usb_serial_driver ark3116_device = { 715 .driver = { 716 .owner = THIS_MODULE, 717 .name = "ark3116", 718 }, 719 .id_table = id_table, 720 .num_ports = 1, 721 .attach = ark3116_attach, 722 .port_probe = ark3116_port_probe, 723 .port_remove = ark3116_port_remove, 724 .set_termios = ark3116_set_termios, 725 .init_termios = ark3116_init_termios, 726 .ioctl = ark3116_ioctl, 727 .tiocmget = ark3116_tiocmget, 728 .tiocmset = ark3116_tiocmset, 729 .get_icount = ark3116_get_icount, 730 .open = ark3116_open, 731 .close = ark3116_close, 732 .break_ctl = ark3116_break_ctl, 733 .read_int_callback = ark3116_read_int_callback, 734 .process_read_urb = ark3116_process_read_urb, 735 }; 736 737 static struct usb_serial_driver * const serial_drivers[] = { 738 &ark3116_device, NULL 739 }; 740 741 module_usb_serial_driver(serial_drivers, id_table); 742 743 MODULE_LICENSE("GPL"); 744 745 MODULE_AUTHOR(DRIVER_AUTHOR); 746 MODULE_DESCRIPTION(DRIVER_DESC); 747 748 /* 749 * The following describes what I learned from studying the old 750 * ark3116.c driver, disassembling the windows driver, and some lucky 751 * guesses. Since I do not have any datasheet or other 752 * documentation, inaccuracies are almost guaranteed. 753 * 754 * Some specs for the ARK3116 can be found here: 755 * http://web.archive.org/web/20060318000438/ 756 * www.arkmicro.com/en/products/view.php?id=10 757 * On that page, 2 GPIO pins are mentioned: I assume these are the 758 * OUT1 and OUT2 pins of the UART, so I added support for those 759 * through the MCR. Since the pins are not available on my hardware, 760 * I could not verify this. 761 * Also, it states there is "on-chip hardware flow control". I have 762 * discovered how to enable that. Unfortunately, I do not know how to 763 * enable XON/XOFF (software) flow control, which would need support 764 * from the chip as well to work. Because of the wording on the web 765 * page there is a real possibility the chip simply does not support 766 * software flow control. 767 * 768 * I got my ark3116 as part of a mobile phone adapter cable. On the 769 * PCB, the following numbered contacts are present: 770 * 771 * 1:- +5V 772 * 2:o DTR 773 * 3:i RX 774 * 4:i DCD 775 * 5:o RTS 776 * 6:o TX 777 * 7:i RI 778 * 8:i DSR 779 * 10:- 0V 780 * 11:i CTS 781 * 782 * On my chip, all signals seem to be 3.3V, but 5V tolerant. But that 783 * may be different for the one you have ;-). 784 * 785 * The windows driver limits the registers to 0-F, so I assume there 786 * are actually 16 present on the device. 787 * 788 * On an UART interrupt, 4 bytes of data come in on the interrupt 789 * endpoint. The bytes are 0xe8 IIR LSR MSR. 790 * 791 * The baudrate seems to be generated from the 12MHz crystal, using 792 * 4-times subsampling. So quot=12e6/(4*baud). Also see description 793 * of register E. 794 * 795 * Registers 0-7: 796 * These seem to be the same as for a regular 16450. The FCR is set 797 * to UART_FCR_DMA_SELECT (0x8), I guess to enable transfers between 798 * the UART and the USB bridge/DMA engine. 799 * 800 * Register 8: 801 * By trial and error, I found out that bit 0 enables hardware CTS, 802 * stopping TX when CTS is +5V. Bit 1 does the same for RTS, making 803 * RTS +5V when the 3116 cannot transfer the data to the USB bus 804 * (verified by disabling the reading URB). Note that as far as I can 805 * tell, the windows driver does NOT use this, so there might be some 806 * hardware bug or something. 807 * 808 * According to a patch provided here 809 * (http://lkml.org/lkml/2009/7/26/56), the ARK3116 can also be used 810 * as an IrDA dongle. Since I do not have such a thing, I could not 811 * investigate that aspect. However, I can speculate ;-). 812 * 813 * - IrDA encodes data differently than RS232. Most likely, one of 814 * the bits in registers 9..E enables the IR ENDEC (encoder/decoder). 815 * - Depending on the IR transceiver, the input and output need to be 816 * inverted, so there are probably bits for that as well. 817 * - IrDA is half-duplex, so there should be a bit for selecting that. 818 * 819 * This still leaves at least two registers unaccounted for. Perhaps 820 * The chip can do XON/XOFF or CRC in HW? 821 * 822 * Register 9: 823 * Set to 0x00 for IrDA, when the baudrate is initialised. 824 * 825 * Register A: 826 * Set to 0x01 for IrDA, at init. 827 * 828 * Register B: 829 * Set to 0x01 for IrDA, 0x00 for RS232, at init. 830 * 831 * Register C: 832 * Set to 00 for IrDA, at init. 833 * 834 * Register D: 835 * Set to 0x41 for IrDA, at init. 836 * 837 * Register E: 838 * Somekind of baudrate override. The windows driver seems to set 839 * this to 0x00 for normal baudrates, 0x01 for 460800, 0x02 for 921600. 840 * Since 460800 and 921600 cannot be obtained by dividing 3MHz by an integer, 841 * it could be somekind of subdivisor thingy. 842 * However,it does not seem to do anything: selecting 921600 (divisor 3, 843 * reg E=2), still gets 1 MHz. I also checked if registers 9, C or F would 844 * work, but they don't. 845 * 846 * Register F: unknown 847 */ 848