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 static int debug; 41 /* 42 * Version information 43 */ 44 45 #define DRIVER_VERSION "v0.5" 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 54 static const struct usb_device_id id_table[] = { 55 { USB_DEVICE(0x6547, 0x0232) }, 56 { USB_DEVICE(0x18ec, 0x3118) }, /* USB to IrDA adapter */ 57 { }, 58 }; 59 MODULE_DEVICE_TABLE(usb, id_table); 60 61 static 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 70 struct 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 90 static 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 } 101 102 static 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 } 116 117 static 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 } 126 127 static 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 } 201 202 static 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 } 215 216 static 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 } 225 226 static 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 } 346 347 static 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 /* shutdown any bulk reads that might be going on */ 359 if (serial->num_bulk_out) 360 usb_kill_urb(port->write_urb); 361 if (serial->num_bulk_in) 362 usb_kill_urb(port->read_urb); 363 if (serial->num_interrupt_in) 364 usb_kill_urb(port->interrupt_in_urb); 365 } 366 } 367 368 static int ark3116_open(struct tty_struct *tty, struct usb_serial_port *port) 369 { 370 struct ark3116_private *priv = usb_get_serial_port_data(port); 371 struct usb_serial *serial = port->serial; 372 unsigned char *buf; 373 int result; 374 375 buf = kmalloc(1, GFP_KERNEL); 376 if (buf == NULL) 377 return -ENOMEM; 378 379 result = usb_serial_generic_open(tty, port); 380 if (result) { 381 dbg("%s - usb_serial_generic_open failed: %d", 382 __func__, result); 383 goto err_out; 384 } 385 386 /* setup termios */ 387 if (tty) 388 ark3116_set_termios(tty, port, NULL); 389 390 /* remove any data still left: also clears error state */ 391 ark3116_read_reg(serial, UART_RX, buf); 392 393 /* read modem status */ 394 priv->msr = ark3116_read_reg(serial, UART_MSR, buf); 395 /* read line status */ 396 priv->lsr = ark3116_read_reg(serial, UART_LSR, buf); 397 398 result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL); 399 if (result) { 400 dev_err(&port->dev, "submit irq_in urb failed %d\n", 401 result); 402 ark3116_close(port); 403 goto err_out; 404 } 405 406 /* activate interrupts */ 407 ark3116_write_reg(port->serial, UART_IER, UART_IER_MSI|UART_IER_RLSI); 408 409 /* enable DMA */ 410 ark3116_write_reg(port->serial, UART_FCR, UART_FCR_DMA_SELECT); 411 412 err_out: 413 kfree(buf); 414 return result; 415 } 416 417 static int ark3116_ioctl(struct tty_struct *tty, struct file *file, 418 unsigned int cmd, unsigned long arg) 419 { 420 struct usb_serial_port *port = tty->driver_data; 421 struct ark3116_private *priv = usb_get_serial_port_data(port); 422 struct serial_struct serstruct; 423 void __user *user_arg = (void __user *)arg; 424 425 switch (cmd) { 426 case TIOCGSERIAL: 427 /* XXX: Some of these values are probably wrong. */ 428 memset(&serstruct, 0, sizeof(serstruct)); 429 serstruct.type = PORT_16654; 430 serstruct.line = port->serial->minor; 431 serstruct.port = port->number; 432 serstruct.custom_divisor = 0; 433 serstruct.baud_base = 460800; 434 435 if (copy_to_user(user_arg, &serstruct, sizeof(serstruct))) 436 return -EFAULT; 437 438 return 0; 439 case TIOCSSERIAL: 440 if (copy_from_user(&serstruct, user_arg, sizeof(serstruct))) 441 return -EFAULT; 442 return 0; 443 case TIOCMIWAIT: 444 for (;;) { 445 struct async_icount prev = priv->icount; 446 interruptible_sleep_on(&priv->delta_msr_wait); 447 /* see if a signal did it */ 448 if (signal_pending(current)) 449 return -ERESTARTSYS; 450 if ((prev.rng == priv->icount.rng) && 451 (prev.dsr == priv->icount.dsr) && 452 (prev.dcd == priv->icount.dcd) && 453 (prev.cts == priv->icount.cts)) 454 return -EIO; 455 if ((arg & TIOCM_RNG && 456 (prev.rng != priv->icount.rng)) || 457 (arg & TIOCM_DSR && 458 (prev.dsr != priv->icount.dsr)) || 459 (arg & TIOCM_CD && 460 (prev.dcd != priv->icount.dcd)) || 461 (arg & TIOCM_CTS && 462 (prev.cts != priv->icount.cts))) 463 return 0; 464 } 465 break; 466 case TIOCGICOUNT: { 467 struct serial_icounter_struct icount; 468 struct async_icount cnow = priv->icount; 469 memset(&icount, 0, sizeof(icount)); 470 icount.cts = cnow.cts; 471 icount.dsr = cnow.dsr; 472 icount.rng = cnow.rng; 473 icount.dcd = cnow.dcd; 474 icount.rx = cnow.rx; 475 icount.tx = cnow.tx; 476 icount.frame = cnow.frame; 477 icount.overrun = cnow.overrun; 478 icount.parity = cnow.parity; 479 icount.brk = cnow.brk; 480 icount.buf_overrun = cnow.buf_overrun; 481 if (copy_to_user(user_arg, &icount, sizeof(icount))) 482 return -EFAULT; 483 return 0; 484 } 485 } 486 487 return -ENOIOCTLCMD; 488 } 489 490 static int ark3116_tiocmget(struct tty_struct *tty, struct file *file) 491 { 492 struct usb_serial_port *port = tty->driver_data; 493 struct ark3116_private *priv = usb_get_serial_port_data(port); 494 __u32 status; 495 __u32 ctrl; 496 unsigned long flags; 497 498 mutex_lock(&priv->hw_lock); 499 ctrl = priv->mcr; 500 mutex_unlock(&priv->hw_lock); 501 502 spin_lock_irqsave(&priv->status_lock, flags); 503 status = priv->msr; 504 spin_unlock_irqrestore(&priv->status_lock, flags); 505 506 return (status & UART_MSR_DSR ? TIOCM_DSR : 0) | 507 (status & UART_MSR_CTS ? TIOCM_CTS : 0) | 508 (status & UART_MSR_RI ? TIOCM_RI : 0) | 509 (status & UART_MSR_DCD ? TIOCM_CD : 0) | 510 (ctrl & UART_MCR_DTR ? TIOCM_DTR : 0) | 511 (ctrl & UART_MCR_RTS ? TIOCM_RTS : 0) | 512 (ctrl & UART_MCR_OUT1 ? TIOCM_OUT1 : 0) | 513 (ctrl & UART_MCR_OUT2 ? TIOCM_OUT2 : 0); 514 } 515 516 static int ark3116_tiocmset(struct tty_struct *tty, struct file *file, 517 unsigned set, unsigned clr) 518 { 519 struct usb_serial_port *port = tty->driver_data; 520 struct ark3116_private *priv = usb_get_serial_port_data(port); 521 522 /* we need to take the mutex here, to make sure that the value 523 * in priv->mcr is actually the one that is in the hardware 524 */ 525 526 mutex_lock(&priv->hw_lock); 527 528 if (set & TIOCM_RTS) 529 priv->mcr |= UART_MCR_RTS; 530 if (set & TIOCM_DTR) 531 priv->mcr |= UART_MCR_DTR; 532 if (set & TIOCM_OUT1) 533 priv->mcr |= UART_MCR_OUT1; 534 if (set & TIOCM_OUT2) 535 priv->mcr |= UART_MCR_OUT2; 536 if (clr & TIOCM_RTS) 537 priv->mcr &= ~UART_MCR_RTS; 538 if (clr & TIOCM_DTR) 539 priv->mcr &= ~UART_MCR_DTR; 540 if (clr & TIOCM_OUT1) 541 priv->mcr &= ~UART_MCR_OUT1; 542 if (clr & TIOCM_OUT2) 543 priv->mcr &= ~UART_MCR_OUT2; 544 545 ark3116_write_reg(port->serial, UART_MCR, priv->mcr); 546 547 mutex_unlock(&priv->hw_lock); 548 549 return 0; 550 } 551 552 static void ark3116_break_ctl(struct tty_struct *tty, int break_state) 553 { 554 struct usb_serial_port *port = tty->driver_data; 555 struct ark3116_private *priv = usb_get_serial_port_data(port); 556 557 /* LCR is also used for other things: protect access */ 558 mutex_lock(&priv->hw_lock); 559 560 if (break_state) 561 priv->lcr |= UART_LCR_SBC; 562 else 563 priv->lcr &= ~UART_LCR_SBC; 564 565 ark3116_write_reg(port->serial, UART_LCR, priv->lcr); 566 567 mutex_unlock(&priv->hw_lock); 568 } 569 570 static void ark3116_update_msr(struct usb_serial_port *port, __u8 msr) 571 { 572 struct ark3116_private *priv = usb_get_serial_port_data(port); 573 unsigned long flags; 574 575 spin_lock_irqsave(&priv->status_lock, flags); 576 priv->msr = msr; 577 spin_unlock_irqrestore(&priv->status_lock, flags); 578 579 if (msr & UART_MSR_ANY_DELTA) { 580 /* update input line counters */ 581 if (msr & UART_MSR_DCTS) 582 priv->icount.cts++; 583 if (msr & UART_MSR_DDSR) 584 priv->icount.dsr++; 585 if (msr & UART_MSR_DDCD) 586 priv->icount.dcd++; 587 if (msr & UART_MSR_TERI) 588 priv->icount.rng++; 589 wake_up_interruptible(&priv->delta_msr_wait); 590 } 591 } 592 593 static void ark3116_update_lsr(struct usb_serial_port *port, __u8 lsr) 594 { 595 struct ark3116_private *priv = usb_get_serial_port_data(port); 596 unsigned long flags; 597 598 spin_lock_irqsave(&priv->status_lock, flags); 599 /* combine bits */ 600 priv->lsr |= lsr; 601 spin_unlock_irqrestore(&priv->status_lock, flags); 602 603 if (lsr&UART_LSR_BRK_ERROR_BITS) { 604 if (lsr & UART_LSR_BI) 605 priv->icount.brk++; 606 if (lsr & UART_LSR_FE) 607 priv->icount.frame++; 608 if (lsr & UART_LSR_PE) 609 priv->icount.parity++; 610 if (lsr & UART_LSR_OE) 611 priv->icount.overrun++; 612 } 613 } 614 615 static void ark3116_read_int_callback(struct urb *urb) 616 { 617 struct usb_serial_port *port = urb->context; 618 int status = urb->status; 619 const __u8 *data = urb->transfer_buffer; 620 int result; 621 622 switch (status) { 623 case -ECONNRESET: 624 case -ENOENT: 625 case -ESHUTDOWN: 626 /* this urb is terminated, clean up */ 627 dbg("%s - urb shutting down with status: %d", 628 __func__, status); 629 return; 630 default: 631 dbg("%s - nonzero urb status received: %d", 632 __func__, status); 633 break; 634 case 0: /* success */ 635 /* discovered this by trail and error... */ 636 if ((urb->actual_length == 4) && (data[0] == 0xe8)) { 637 const __u8 id = data[1]&UART_IIR_ID; 638 dbg("%s: iir=%02x", __func__, data[1]); 639 if (id == UART_IIR_MSI) { 640 dbg("%s: msr=%02x", __func__, data[3]); 641 ark3116_update_msr(port, data[3]); 642 break; 643 } else if (id == UART_IIR_RLSI) { 644 dbg("%s: lsr=%02x", __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(debug, &port->dev, 653 __func__, 654 urb->actual_length, 655 urb->transfer_buffer); 656 break; 657 } 658 659 result = usb_submit_urb(urb, GFP_ATOMIC); 660 if (result) 661 dev_err(&urb->dev->dev, 662 "%s - Error %d submitting interrupt urb\n", 663 __func__, result); 664 } 665 666 667 /* Data comes in via the bulk (data) URB, erors/interrupts via the int URB. 668 * This means that we cannot be sure which data byte has an associated error 669 * condition, so we report an error for all data in the next bulk read. 670 * 671 * Actually, there might even be a window between the bulk data leaving the 672 * ark and reading/resetting the lsr in the read_bulk_callback where an 673 * interrupt for the next data block could come in. 674 * Without somekind of ordering on the ark, we would have to report the 675 * error for the next block of data as well... 676 * For now, let's pretend this can't happen. 677 */ 678 679 static void send_to_tty(struct tty_struct *tty, 680 const unsigned char *chars, 681 size_t size, char flag) 682 { 683 if (size == 0) 684 return; 685 if (flag == TTY_NORMAL) { 686 tty_insert_flip_string(tty, chars, size); 687 } else { 688 int i; 689 for (i = 0; i < size; ++i) 690 tty_insert_flip_char(tty, chars[i], flag); 691 } 692 } 693 694 static void ark3116_read_bulk_callback(struct urb *urb) 695 { 696 struct usb_serial_port *port = urb->context; 697 struct ark3116_private *priv = usb_get_serial_port_data(port); 698 const __u8 *data = urb->transfer_buffer; 699 int status = urb->status; 700 struct tty_struct *tty; 701 unsigned long flags; 702 int result; 703 char flag; 704 __u32 lsr; 705 706 switch (status) { 707 case -ECONNRESET: 708 case -ENOENT: 709 case -ESHUTDOWN: 710 /* this urb is terminated, clean up */ 711 dbg("%s - urb shutting down with status: %d", 712 __func__, status); 713 return; 714 default: 715 dbg("%s - nonzero urb status received: %d", 716 __func__, status); 717 break; 718 case 0: /* success */ 719 720 spin_lock_irqsave(&priv->status_lock, flags); 721 lsr = priv->lsr; 722 /* clear error bits */ 723 priv->lsr &= ~UART_LSR_BRK_ERROR_BITS; 724 spin_unlock_irqrestore(&priv->status_lock, flags); 725 726 if (unlikely(lsr & UART_LSR_BI)) 727 flag = TTY_BREAK; 728 else if (unlikely(lsr & UART_LSR_PE)) 729 flag = TTY_PARITY; 730 else if (unlikely(lsr & UART_LSR_FE)) 731 flag = TTY_FRAME; 732 else 733 flag = TTY_NORMAL; 734 735 tty = tty_port_tty_get(&port->port); 736 if (tty) { 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