ieee1284_ops.c 23.2 KB
Newer Older
Linus Torvalds's avatar
Linus Torvalds committed
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61
/* IEEE-1284 operations for parport.
 *
 * This file is for generic IEEE 1284 operations.  The idea is that
 * they are used by the low-level drivers.  If they have a special way
 * of doing something, they can provide their own routines (and put
 * the function pointers in port->ops); if not, they can just use these
 * as a fallback.
 *
 * Note: Make no assumptions about hardware or architecture in this file!
 *
 * Author: Tim Waugh <tim@cyberelk.demon.co.uk>
 * Fixed AUTOFD polarity in ecp_forward_to_reverse().  Fred Barnes, 1999
 * Software emulated EPP fixes, Fred Barnes, 04/2001.
 */


#include <linux/module.h>
#include <linux/parport.h>
#include <linux/delay.h>
#include <linux/sched.h>
#include <asm/uaccess.h>

#undef DEBUG /* undef me for production */

#ifdef CONFIG_LP_CONSOLE
#undef DEBUG /* Don't want a garbled console */
#endif

#ifdef DEBUG
#define DPRINTK(stuff...) printk (stuff)
#else
#define DPRINTK(stuff...)
#endif

/***                                *
 * One-way data transfer functions. *
 *                                ***/

/* Compatibility mode. */
size_t parport_ieee1284_write_compat (struct parport *port,
				      const void *buffer, size_t len,
				      int flags)
{
	int no_irq = 1;
	ssize_t count = 0;
	const unsigned char *addr = buffer;
	unsigned char byte;
	struct pardevice *dev = port->physport->cad;
	unsigned char ctl = (PARPORT_CONTROL_SELECT
			     | PARPORT_CONTROL_INIT);

	if (port->irq != PARPORT_IRQ_NONE) {
		parport_enable_irq (port);
		no_irq = 0;
	}

	port->physport->ieee1284.phase = IEEE1284_PH_FWD_DATA;
	parport_write_control (port, ctl);
	parport_data_forward (port);
	while (count < len) {
		unsigned long expire = jiffies + dev->timeout;
62
		long wait = msecs_to_jiffies(10);
Linus Torvalds's avatar
Linus Torvalds committed
63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98
		unsigned char mask = (PARPORT_STATUS_ERROR
				      | PARPORT_STATUS_BUSY);
		unsigned char val = (PARPORT_STATUS_ERROR
				     | PARPORT_STATUS_BUSY);

		/* Wait until the peripheral's ready */
		do {
			/* Is the peripheral ready yet? */
			if (!parport_wait_peripheral (port, mask, val))
				/* Skip the loop */
				goto ready;

			/* Is the peripheral upset? */
			if ((parport_read_status (port) &
			     (PARPORT_STATUS_PAPEROUT |
			      PARPORT_STATUS_SELECT |
			      PARPORT_STATUS_ERROR))
			    != (PARPORT_STATUS_SELECT |
				PARPORT_STATUS_ERROR))
				/* If nFault is asserted (i.e. no
				 * error) and PAPEROUT and SELECT are
				 * just red herrings, give the driver
				 * a chance to check it's happy with
				 * that before continuing. */
				goto stop;

			/* Have we run out of time? */
			if (!time_before (jiffies, expire))
				break;

			/* Yield the port for a while.  If this is the
                           first time around the loop, don't let go of
                           the port.  This way, we find out if we have
                           our interrupt handler called. */
			if (count && no_irq) {
				parport_release (dev);
99
				schedule_timeout_interruptible(wait);
Linus Torvalds's avatar
Linus Torvalds committed
100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166
				parport_claim_or_block (dev);
			}
			else
				/* We must have the device claimed here */
				parport_wait_event (port, wait);

			/* Is there a signal pending? */
			if (signal_pending (current))
				break;

			/* Wait longer next time. */
			wait *= 2;
		} while (time_before (jiffies, expire));

		if (signal_pending (current))
			break;

		DPRINTK (KERN_DEBUG "%s: Timed out\n", port->name);
		break;

	ready:
		/* Write the character to the data lines. */
		byte = *addr++;
		parport_write_data (port, byte);
		udelay (1);

		/* Pulse strobe. */
		parport_write_control (port, ctl | PARPORT_CONTROL_STROBE);
		udelay (1); /* strobe */

		parport_write_control (port, ctl);
		udelay (1); /* hold */

		/* Assume the peripheral received it. */
		count++;

                /* Let another process run if it needs to. */
		if (time_before (jiffies, expire))
			if (!parport_yield_blocking (dev)
			    && need_resched())
				schedule ();
	}
 stop:
	port->physport->ieee1284.phase = IEEE1284_PH_FWD_IDLE;

	return count;
}

/* Nibble mode. */
size_t parport_ieee1284_read_nibble (struct parport *port, 
				     void *buffer, size_t len,
				     int flags)
{
#ifndef CONFIG_PARPORT_1284
	return 0;
#else
	unsigned char *buf = buffer;
	int i;
	unsigned char byte = 0;

	len *= 2; /* in nibbles */
	for (i=0; i < len; i++) {
		unsigned char nibble;

		/* Does the error line indicate end of data? */
		if (((i & 1) == 0) &&
		    (parport_read_status(port) & PARPORT_STATUS_ERROR)) {
Marko Kohtala's avatar
Marko Kohtala committed
167
			goto end_of_data;
Linus Torvalds's avatar
Linus Torvalds committed
168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218
		}

		/* Event 7: Set nAutoFd low. */
		parport_frob_control (port,
				      PARPORT_CONTROL_AUTOFD,
				      PARPORT_CONTROL_AUTOFD);

		/* Event 9: nAck goes low. */
		port->ieee1284.phase = IEEE1284_PH_REV_DATA;
		if (parport_wait_peripheral (port,
					     PARPORT_STATUS_ACK, 0)) {
			/* Timeout -- no more data? */
			DPRINTK (KERN_DEBUG
				 "%s: Nibble timeout at event 9 (%d bytes)\n",
				 port->name, i/2);
			parport_frob_control (port, PARPORT_CONTROL_AUTOFD, 0);
			break;
		}


		/* Read a nibble. */
		nibble = parport_read_status (port) >> 3;
		nibble &= ~8;
		if ((nibble & 0x10) == 0)
			nibble |= 8;
		nibble &= 0xf;

		/* Event 10: Set nAutoFd high. */
		parport_frob_control (port, PARPORT_CONTROL_AUTOFD, 0);

		/* Event 11: nAck goes high. */
		if (parport_wait_peripheral (port,
					     PARPORT_STATUS_ACK,
					     PARPORT_STATUS_ACK)) {
			/* Timeout -- no more data? */
			DPRINTK (KERN_DEBUG
				 "%s: Nibble timeout at event 11\n",
				 port->name);
			break;
		}

		if (i & 1) {
			/* Second nibble */
			byte |= nibble << 4;
			*buf++ = byte;
		} else 
			byte = nibble;
	}

	if (i == len) {
		/* Read the last nibble without checking data avail. */
Marko Kohtala's avatar
Marko Kohtala committed
219 220 221 222 223 224 225 226 227 228 229 230
		if (parport_read_status (port) & PARPORT_STATUS_ERROR) {
		end_of_data:
			DPRINTK (KERN_DEBUG
				"%s: No more nibble data (%d bytes)\n",
				port->name, i/2);

			/* Go to reverse idle phase. */
			parport_frob_control (port,
					      PARPORT_CONTROL_AUTOFD,
					      PARPORT_CONTROL_AUTOFD);
			port->physport->ieee1284.phase = IEEE1284_PH_REV_IDLE;
		}
Linus Torvalds's avatar
Linus Torvalds committed
231
		else
Marko Kohtala's avatar
Marko Kohtala committed
232
			port->physport->ieee1284.phase = IEEE1284_PH_HBUSY_DAVAIL;
Linus Torvalds's avatar
Linus Torvalds committed
233 234
	}

Marko Kohtala's avatar
Marko Kohtala committed
235
	return i/2;
Linus Torvalds's avatar
Linus Torvalds committed
236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254
#endif /* IEEE1284 support */
}

/* Byte mode. */
size_t parport_ieee1284_read_byte (struct parport *port,
				   void *buffer, size_t len,
				   int flags)
{
#ifndef CONFIG_PARPORT_1284
	return 0;
#else
	unsigned char *buf = buffer;
	ssize_t count = 0;

	for (count = 0; count < len; count++) {
		unsigned char byte;

		/* Data available? */
		if (parport_read_status (port) & PARPORT_STATUS_ERROR) {
Marko Kohtala's avatar
Marko Kohtala committed
255
			goto end_of_data;
Linus Torvalds's avatar
Linus Torvalds committed
256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306
		}

		/* Event 14: Place data bus in high impedance state. */
		parport_data_reverse (port);

		/* Event 7: Set nAutoFd low. */
		parport_frob_control (port,
				      PARPORT_CONTROL_AUTOFD,
				      PARPORT_CONTROL_AUTOFD);

		/* Event 9: nAck goes low. */
		port->physport->ieee1284.phase = IEEE1284_PH_REV_DATA;
		if (parport_wait_peripheral (port,
					     PARPORT_STATUS_ACK,
					     0)) {
			/* Timeout -- no more data? */
			parport_frob_control (port, PARPORT_CONTROL_AUTOFD,
						 0);
			DPRINTK (KERN_DEBUG "%s: Byte timeout at event 9\n",
				 port->name);
			break;
		}

		byte = parport_read_data (port);
		*buf++ = byte;

		/* Event 10: Set nAutoFd high */
		parport_frob_control (port, PARPORT_CONTROL_AUTOFD, 0);

		/* Event 11: nAck goes high. */
		if (parport_wait_peripheral (port,
					     PARPORT_STATUS_ACK,
					     PARPORT_STATUS_ACK)) {
			/* Timeout -- no more data? */
			DPRINTK (KERN_DEBUG "%s: Byte timeout at event 11\n",
				 port->name);
			break;
		}

		/* Event 16: Set nStrobe low. */
		parport_frob_control (port,
				      PARPORT_CONTROL_STROBE,
				      PARPORT_CONTROL_STROBE);
		udelay (5);

		/* Event 17: Set nStrobe high. */
		parport_frob_control (port, PARPORT_CONTROL_STROBE, 0);
	}

	if (count == len) {
		/* Read the last byte without checking data avail. */
Marko Kohtala's avatar
Marko Kohtala committed
307 308 309 310 311 312 313 314 315 316 317 318
		if (parport_read_status (port) & PARPORT_STATUS_ERROR) {
		end_of_data:
			DPRINTK (KERN_DEBUG
				 "%s: No more byte data (%Zd bytes)\n",
				 port->name, count);

			/* Go to reverse idle phase. */
			parport_frob_control (port,
					      PARPORT_CONTROL_AUTOFD,
					      PARPORT_CONTROL_AUTOFD);
			port->physport->ieee1284.phase = IEEE1284_PH_REV_IDLE;
		}
Linus Torvalds's avatar
Linus Torvalds committed
319
		else
Marko Kohtala's avatar
Marko Kohtala committed
320
			port->physport->ieee1284.phase = IEEE1284_PH_HBUSY_DAVAIL;
Linus Torvalds's avatar
Linus Torvalds committed
321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538
	}

	return count;
#endif /* IEEE1284 support */
}

/***              *
 * ECP Functions. *
 *              ***/

#ifdef CONFIG_PARPORT_1284

static inline
int ecp_forward_to_reverse (struct parport *port)
{
	int retval;

	/* Event 38: Set nAutoFd low */
	parport_frob_control (port,
			      PARPORT_CONTROL_AUTOFD,
			      PARPORT_CONTROL_AUTOFD);
	parport_data_reverse (port);
	udelay (5);

	/* Event 39: Set nInit low to initiate bus reversal */
	parport_frob_control (port,
			      PARPORT_CONTROL_INIT,
			      0);

	/* Event 40: PError goes low */
	retval = parport_wait_peripheral (port,
					  PARPORT_STATUS_PAPEROUT, 0);

	if (!retval) {
		DPRINTK (KERN_DEBUG "%s: ECP direction: reverse\n",
			 port->name);
		port->ieee1284.phase = IEEE1284_PH_REV_IDLE;
	} else {
		DPRINTK (KERN_DEBUG "%s: ECP direction: failed to reverse\n",
			 port->name);
		port->ieee1284.phase = IEEE1284_PH_ECP_DIR_UNKNOWN;
	}

	return retval;
}

static inline
int ecp_reverse_to_forward (struct parport *port)
{
	int retval;

	/* Event 47: Set nInit high */
	parport_frob_control (port,
			      PARPORT_CONTROL_INIT
			      | PARPORT_CONTROL_AUTOFD,
			      PARPORT_CONTROL_INIT
			      | PARPORT_CONTROL_AUTOFD);

	/* Event 49: PError goes high */
	retval = parport_wait_peripheral (port,
					  PARPORT_STATUS_PAPEROUT,
					  PARPORT_STATUS_PAPEROUT);

	if (!retval) {
		parport_data_forward (port);
		DPRINTK (KERN_DEBUG "%s: ECP direction: forward\n",
			 port->name);
		port->ieee1284.phase = IEEE1284_PH_FWD_IDLE;
	} else {
		DPRINTK (KERN_DEBUG
			 "%s: ECP direction: failed to switch forward\n",
			 port->name);
		port->ieee1284.phase = IEEE1284_PH_ECP_DIR_UNKNOWN;
	}


	return retval;
}

#endif /* IEEE1284 support */

/* ECP mode, forward channel, data. */
size_t parport_ieee1284_ecp_write_data (struct parport *port,
					const void *buffer, size_t len,
					int flags)
{
#ifndef CONFIG_PARPORT_1284
	return 0;
#else
	const unsigned char *buf = buffer;
	size_t written;
	int retry;

	port = port->physport;

	if (port->ieee1284.phase != IEEE1284_PH_FWD_IDLE)
		if (ecp_reverse_to_forward (port))
			return 0;

	port->ieee1284.phase = IEEE1284_PH_FWD_DATA;

	/* HostAck high (data, not command) */
	parport_frob_control (port,
			      PARPORT_CONTROL_AUTOFD
			      | PARPORT_CONTROL_STROBE
			      | PARPORT_CONTROL_INIT,
			      PARPORT_CONTROL_INIT);
	for (written = 0; written < len; written++, buf++) {
		unsigned long expire = jiffies + port->cad->timeout;
		unsigned char byte;

		byte = *buf;
	try_again:
		parport_write_data (port, byte);
		parport_frob_control (port, PARPORT_CONTROL_STROBE,
				      PARPORT_CONTROL_STROBE);
		udelay (5);
		for (retry = 0; retry < 100; retry++) {
			if (!parport_wait_peripheral (port,
						      PARPORT_STATUS_BUSY, 0))
				goto success;

			if (signal_pending (current)) {
				parport_frob_control (port,
						      PARPORT_CONTROL_STROBE,
						      0);
				break;
			}
		}

		/* Time for Host Transfer Recovery (page 41 of IEEE1284) */
		DPRINTK (KERN_DEBUG "%s: ECP transfer stalled!\n", port->name);

		parport_frob_control (port, PARPORT_CONTROL_INIT,
				      PARPORT_CONTROL_INIT);
		udelay (50);
		if (parport_read_status (port) & PARPORT_STATUS_PAPEROUT) {
			/* It's buggered. */
			parport_frob_control (port, PARPORT_CONTROL_INIT, 0);
			break;
		}

		parport_frob_control (port, PARPORT_CONTROL_INIT, 0);
		udelay (50);
		if (!(parport_read_status (port) & PARPORT_STATUS_PAPEROUT))
			break;

		DPRINTK (KERN_DEBUG "%s: Host transfer recovered\n",
			 port->name);

		if (time_after_eq (jiffies, expire)) break;
		goto try_again;
	success:
		parport_frob_control (port, PARPORT_CONTROL_STROBE, 0);
		udelay (5);
		if (parport_wait_peripheral (port,
					     PARPORT_STATUS_BUSY,
					     PARPORT_STATUS_BUSY))
			/* Peripheral hasn't accepted the data. */
			break;
	}

	port->ieee1284.phase = IEEE1284_PH_FWD_IDLE;

	return written;
#endif /* IEEE1284 support */
}

/* ECP mode, reverse channel, data. */
size_t parport_ieee1284_ecp_read_data (struct parport *port,
				       void *buffer, size_t len, int flags)
{
#ifndef CONFIG_PARPORT_1284
	return 0;
#else
	struct pardevice *dev = port->cad;
	unsigned char *buf = buffer;
	int rle_count = 0; /* shut gcc up */
	unsigned char ctl;
	int rle = 0;
	ssize_t count = 0;

	port = port->physport;

	if (port->ieee1284.phase != IEEE1284_PH_REV_IDLE)
		if (ecp_forward_to_reverse (port))
			return 0;

	port->ieee1284.phase = IEEE1284_PH_REV_DATA;

	/* Set HostAck low to start accepting data. */
	ctl = parport_read_control (port);
	ctl &= ~(PARPORT_CONTROL_STROBE | PARPORT_CONTROL_INIT |
		 PARPORT_CONTROL_AUTOFD);
	parport_write_control (port,
			       ctl | PARPORT_CONTROL_AUTOFD);
	while (count < len) {
		unsigned long expire = jiffies + dev->timeout;
		unsigned char byte;
		int command;

		/* Event 43: Peripheral sets nAck low. It can take as
                   long as it wants. */
		while (parport_wait_peripheral (port, PARPORT_STATUS_ACK, 0)) {
			/* The peripheral hasn't given us data in
			   35ms.  If we have data to give back to the
			   caller, do it now. */
			if (count)
				goto out;

			/* If we've used up all the time we were allowed,
			   give up altogether. */
			if (!time_before (jiffies, expire))
				goto out;

			/* Yield the port for a while. */
			if (count && dev->port->irq != PARPORT_IRQ_NONE) {
				parport_release (dev);
539
				schedule_timeout_interruptible(msecs_to_jiffies(40));
Linus Torvalds's avatar
Linus Torvalds committed
540 541 542 543
				parport_claim_or_block (dev);
			}
			else
				/* We must have the device claimed here. */
544
				parport_wait_event (port, msecs_to_jiffies(40));
Linus Torvalds's avatar
Linus Torvalds committed
545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890

			/* Is there a signal pending? */
			if (signal_pending (current))
				goto out;
		}

		/* Is this a command? */
		if (rle)
			/* The last byte was a run-length count, so
                           this can't be as well. */
			command = 0;
		else
			command = (parport_read_status (port) &
				   PARPORT_STATUS_BUSY) ? 1 : 0;

		/* Read the data. */
		byte = parport_read_data (port);

		/* If this is a channel command, rather than an RLE
                   command or a normal data byte, don't accept it. */
		if (command) {
			if (byte & 0x80) {
				DPRINTK (KERN_DEBUG "%s: stopping short at "
					 "channel command (%02x)\n",
					 port->name, byte);
				goto out;
			}
			else if (port->ieee1284.mode != IEEE1284_MODE_ECPRLE)
				DPRINTK (KERN_DEBUG "%s: device illegally "
					 "using RLE; accepting anyway\n",
					 port->name);

			rle_count = byte + 1;

			/* Are we allowed to read that many bytes? */
			if (rle_count > (len - count)) {
				DPRINTK (KERN_DEBUG "%s: leaving %d RLE bytes "
					 "for next time\n", port->name,
					 rle_count);
				break;
			}

			rle = 1;
		}

		/* Event 44: Set HostAck high, acknowledging handshake. */
		parport_write_control (port, ctl);

		/* Event 45: The peripheral has 35ms to set nAck high. */
		if (parport_wait_peripheral (port, PARPORT_STATUS_ACK,
					     PARPORT_STATUS_ACK)) {
			/* It's gone wrong.  Return what data we have
                           to the caller. */
			DPRINTK (KERN_DEBUG "ECP read timed out at 45\n");

			if (command)
				printk (KERN_WARNING
					"%s: command ignored (%02x)\n",
					port->name, byte);

			break;
		}

		/* Event 46: Set HostAck low and accept the data. */
		parport_write_control (port,
				       ctl | PARPORT_CONTROL_AUTOFD);

		/* If we just read a run-length count, fetch the data. */
		if (command)
			continue;

		/* If this is the byte after a run-length count, decompress. */
		if (rle) {
			rle = 0;
			memset (buf, byte, rle_count);
			buf += rle_count;
			count += rle_count;
			DPRINTK (KERN_DEBUG "%s: decompressed to %d bytes\n",
				 port->name, rle_count);
		} else {
			/* Normal data byte. */
			*buf = byte;
			buf++, count++;
		}
	}

 out:
	port->ieee1284.phase = IEEE1284_PH_REV_IDLE;
	return count;
#endif /* IEEE1284 support */
}

/* ECP mode, forward channel, commands. */
size_t parport_ieee1284_ecp_write_addr (struct parport *port,
					const void *buffer, size_t len,
					int flags)
{
#ifndef CONFIG_PARPORT_1284
	return 0;
#else
	const unsigned char *buf = buffer;
	size_t written;
	int retry;

	port = port->physport;

	if (port->ieee1284.phase != IEEE1284_PH_FWD_IDLE)
		if (ecp_reverse_to_forward (port))
			return 0;

	port->ieee1284.phase = IEEE1284_PH_FWD_DATA;

	/* HostAck low (command, not data) */
	parport_frob_control (port,
			      PARPORT_CONTROL_AUTOFD
			      | PARPORT_CONTROL_STROBE
			      | PARPORT_CONTROL_INIT,
			      PARPORT_CONTROL_AUTOFD
			      | PARPORT_CONTROL_INIT);
	for (written = 0; written < len; written++, buf++) {
		unsigned long expire = jiffies + port->cad->timeout;
		unsigned char byte;

		byte = *buf;
	try_again:
		parport_write_data (port, byte);
		parport_frob_control (port, PARPORT_CONTROL_STROBE,
				      PARPORT_CONTROL_STROBE);
		udelay (5);
		for (retry = 0; retry < 100; retry++) {
			if (!parport_wait_peripheral (port,
						      PARPORT_STATUS_BUSY, 0))
				goto success;

			if (signal_pending (current)) {
				parport_frob_control (port,
						      PARPORT_CONTROL_STROBE,
						      0);
				break;
			}
		}

		/* Time for Host Transfer Recovery (page 41 of IEEE1284) */
		DPRINTK (KERN_DEBUG "%s: ECP transfer stalled!\n", port->name);

		parport_frob_control (port, PARPORT_CONTROL_INIT,
				      PARPORT_CONTROL_INIT);
		udelay (50);
		if (parport_read_status (port) & PARPORT_STATUS_PAPEROUT) {
			/* It's buggered. */
			parport_frob_control (port, PARPORT_CONTROL_INIT, 0);
			break;
		}

		parport_frob_control (port, PARPORT_CONTROL_INIT, 0);
		udelay (50);
		if (!(parport_read_status (port) & PARPORT_STATUS_PAPEROUT))
			break;

		DPRINTK (KERN_DEBUG "%s: Host transfer recovered\n",
			 port->name);

		if (time_after_eq (jiffies, expire)) break;
		goto try_again;
	success:
		parport_frob_control (port, PARPORT_CONTROL_STROBE, 0);
		udelay (5);
		if (parport_wait_peripheral (port,
					     PARPORT_STATUS_BUSY,
					     PARPORT_STATUS_BUSY))
			/* Peripheral hasn't accepted the data. */
			break;
	}

	port->ieee1284.phase = IEEE1284_PH_FWD_IDLE;

	return written;
#endif /* IEEE1284 support */
}

/***              *
 * EPP functions. *
 *              ***/

/* EPP mode, forward channel, data. */
size_t parport_ieee1284_epp_write_data (struct parport *port,
					const void *buffer, size_t len,
					int flags)
{
	unsigned char *bp = (unsigned char *) buffer;
	size_t ret = 0;

	/* set EPP idle state (just to make sure) with strobe low */
	parport_frob_control (port,
			      PARPORT_CONTROL_STROBE |
			      PARPORT_CONTROL_AUTOFD |
			      PARPORT_CONTROL_SELECT |
			      PARPORT_CONTROL_INIT,
			      PARPORT_CONTROL_STROBE |
			      PARPORT_CONTROL_INIT);
	port->ops->data_forward (port);
	for (; len > 0; len--, bp++) {
		/* Event 62: Write data and set autofd low */
		parport_write_data (port, *bp);
		parport_frob_control (port, PARPORT_CONTROL_AUTOFD,
				      PARPORT_CONTROL_AUTOFD);

		/* Event 58: wait for busy (nWait) to go high */
		if (parport_poll_peripheral (port, PARPORT_STATUS_BUSY, 0, 10))
			break;

		/* Event 63: set nAutoFd (nDStrb) high */
		parport_frob_control (port, PARPORT_CONTROL_AUTOFD, 0);

		/* Event 60: wait for busy (nWait) to go low */
		if (parport_poll_peripheral (port, PARPORT_STATUS_BUSY,
					     PARPORT_STATUS_BUSY, 5))
			break;

		ret++;
	}

	/* Event 61: set strobe (nWrite) high */
	parport_frob_control (port, PARPORT_CONTROL_STROBE, 0);

	return ret;
}

/* EPP mode, reverse channel, data. */
size_t parport_ieee1284_epp_read_data (struct parport *port,
				       void *buffer, size_t len,
				       int flags)
{
	unsigned char *bp = (unsigned char *) buffer;
	unsigned ret = 0;

	/* set EPP idle state (just to make sure) with strobe high */
	parport_frob_control (port,
			      PARPORT_CONTROL_STROBE |
			      PARPORT_CONTROL_AUTOFD |
			      PARPORT_CONTROL_SELECT |
			      PARPORT_CONTROL_INIT,
			      PARPORT_CONTROL_INIT);
	port->ops->data_reverse (port);
	for (; len > 0; len--, bp++) {
		/* Event 67: set nAutoFd (nDStrb) low */
		parport_frob_control (port,
				      PARPORT_CONTROL_AUTOFD,
				      PARPORT_CONTROL_AUTOFD);
		/* Event 58: wait for Busy to go high */
		if (parport_wait_peripheral (port, PARPORT_STATUS_BUSY, 0)) {
			break;
		}

		*bp = parport_read_data (port);

		/* Event 63: set nAutoFd (nDStrb) high */
		parport_frob_control (port, PARPORT_CONTROL_AUTOFD, 0);

		/* Event 60: wait for Busy to go low */
		if (parport_poll_peripheral (port, PARPORT_STATUS_BUSY,
					     PARPORT_STATUS_BUSY, 5)) {
			break;
		}

		ret++;
	}
	port->ops->data_forward (port);

	return ret;
}

/* EPP mode, forward channel, addresses. */
size_t parport_ieee1284_epp_write_addr (struct parport *port,
					const void *buffer, size_t len,
					int flags)
{
	unsigned char *bp = (unsigned char *) buffer;
	size_t ret = 0;

	/* set EPP idle state (just to make sure) with strobe low */
	parport_frob_control (port,
			      PARPORT_CONTROL_STROBE |
			      PARPORT_CONTROL_AUTOFD |
			      PARPORT_CONTROL_SELECT |
			      PARPORT_CONTROL_INIT,
			      PARPORT_CONTROL_STROBE |
			      PARPORT_CONTROL_INIT);
	port->ops->data_forward (port);
	for (; len > 0; len--, bp++) {
		/* Event 56: Write data and set nAStrb low. */
		parport_write_data (port, *bp);
		parport_frob_control (port, PARPORT_CONTROL_SELECT,
				      PARPORT_CONTROL_SELECT);

		/* Event 58: wait for busy (nWait) to go high */
		if (parport_poll_peripheral (port, PARPORT_STATUS_BUSY, 0, 10))
			break;

		/* Event 59: set nAStrb high */
		parport_frob_control (port, PARPORT_CONTROL_SELECT, 0);

		/* Event 60: wait for busy (nWait) to go low */
		if (parport_poll_peripheral (port, PARPORT_STATUS_BUSY,
					     PARPORT_STATUS_BUSY, 5))
			break;

		ret++;
	}

	/* Event 61: set strobe (nWrite) high */
	parport_frob_control (port, PARPORT_CONTROL_STROBE, 0);

	return ret;
}

/* EPP mode, reverse channel, addresses. */
size_t parport_ieee1284_epp_read_addr (struct parport *port,
				       void *buffer, size_t len,
				       int flags)
{
	unsigned char *bp = (unsigned char *) buffer;
	unsigned ret = 0;

	/* Set EPP idle state (just to make sure) with strobe high */
	parport_frob_control (port,
			      PARPORT_CONTROL_STROBE |
			      PARPORT_CONTROL_AUTOFD |
			      PARPORT_CONTROL_SELECT |
			      PARPORT_CONTROL_INIT,
			      PARPORT_CONTROL_INIT);
	port->ops->data_reverse (port);
	for (; len > 0; len--, bp++) {
		/* Event 64: set nSelectIn (nAStrb) low */
		parport_frob_control (port, PARPORT_CONTROL_SELECT,
				      PARPORT_CONTROL_SELECT);

		/* Event 58: wait for Busy to go high */
		if (parport_wait_peripheral (port, PARPORT_STATUS_BUSY, 0)) {
			break;
		}

		*bp = parport_read_data (port);

		/* Event 59: set nSelectIn (nAStrb) high */
		parport_frob_control (port, PARPORT_CONTROL_SELECT,
891
				      0);
Linus Torvalds's avatar
Linus Torvalds committed
892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914

		/* Event 60: wait for Busy to go low */
		if (parport_poll_peripheral (port, PARPORT_STATUS_BUSY, 
					     PARPORT_STATUS_BUSY, 5))
			break;

		ret++;
	}
	port->ops->data_forward (port);

	return ret;
}

EXPORT_SYMBOL(parport_ieee1284_ecp_write_data);
EXPORT_SYMBOL(parport_ieee1284_ecp_read_data);
EXPORT_SYMBOL(parport_ieee1284_ecp_write_addr);
EXPORT_SYMBOL(parport_ieee1284_write_compat);
EXPORT_SYMBOL(parport_ieee1284_read_nibble);
EXPORT_SYMBOL(parport_ieee1284_read_byte);
EXPORT_SYMBOL(parport_ieee1284_epp_write_data);
EXPORT_SYMBOL(parport_ieee1284_epp_read_data);
EXPORT_SYMBOL(parport_ieee1284_epp_write_addr);
EXPORT_SYMBOL(parport_ieee1284_epp_read_addr);