1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * Serial driver for the amiga builtin port.
   4 *
   5 * This code was created by taking serial.c version 4.30 from kernel
   6 * release 2.3.22, replacing all hardware related stuff with the
   7 * corresponding amiga hardware actions, and removing all irrelevant
   8 * code. As a consequence, it uses many of the constants and names
   9 * associated with the registers and bits of 16550 compatible UARTS -
  10 * but only to keep track of status, etc in the state variables. It
  11 * was done this was to make it easier to keep the code in line with
  12 * (non hardware specific) changes to serial.c.
  13 *
  14 * The port is registered with the tty driver as minor device 64, and
  15 * therefore other ports should only use 65 upwards.
  16 *
  17 * Richard Lucock 28/12/99
  18 *
  19 *  Copyright (C) 1991, 1992  Linus Torvalds
  20 *  Copyright (C) 1992, 1993, 1994, 1995, 1996, 1997, 
  21 * 		1998, 1999  Theodore Ts'o
  22 *
  23 */
  24
  25/* Set of debugging defines */
  26
  27#undef SERIAL_DEBUG_INTR
  28#undef SERIAL_DEBUG_OPEN
  29#undef SERIAL_DEBUG_FLOW
  30#undef SERIAL_DEBUG_RS_WAIT_UNTIL_SENT
  31
  32/*
  33 * End of serial driver configuration section.
  34 */
  35
  36#include <linux/bitops.h>
  37#include <linux/circ_buf.h>
  38#include <linux/console.h>
  39#include <linux/delay.h>
  40#include <linux/errno.h>
  41#include <linux/fcntl.h>
  42#include <linux/init.h>
  43#include <linux/interrupt.h>
  44#include <linux/ioport.h>
  45#include <linux/kernel.h>
  46#include <linux/major.h>
  47#include <linux/mm.h>
  48#include <linux/module.h>
  49#include <linux/platform_device.h>
  50#include <linux/ptrace.h>
  51#include <linux/seq_file.h>
  52#include <linux/serial.h>
  53#include <linux/serial_reg.h>
  54#include <linux/serial_core.h>
  55#include <linux/sched.h>
  56#include <linux/signal.h>
  57#include <linux/slab.h>
  58#include <linux/string.h>
  59#include <linux/timer.h>
  60#include <linux/tty_flip.h>
  61#include <linux/tty.h>
  62#include <linux/types.h>
  63#include <linux/uaccess.h>
  64
  65#include <asm/amigahw.h>
  66#include <asm/amigaints.h>
  67#include <asm/irq.h>
  68#include <asm/setup.h>
  69
  70struct serial_state {
  71	struct tty_port		tport;
  72	struct circ_buf		xmit;
  73	struct async_icount	icount;
  74
  75	unsigned long		port;
  76	int			baud_base;
  77	int			custom_divisor;
  78	int			read_status_mask;
  79	int			ignore_status_mask;
  80	int			timeout;
  81	int			quot;
  82	int			IER; 	/* Interrupt Enable Register */
  83	int			MCR; 	/* Modem control register */
  84	u8			x_char;	/* xon/xoff character */
  85};
  86
  87static struct tty_driver *serial_driver;
  88
  89/* number of characters left in xmit buffer before we ask for more */
  90#define WAKEUP_CHARS 256
  91
  92#define XMIT_FIFO_SIZE 1
  93
  94static unsigned char current_ctl_bits;
  95
  96static void change_speed(struct tty_struct *tty, struct serial_state *info,
  97			 const struct ktermios *old);
  98static void rs_wait_until_sent(struct tty_struct *tty, int timeout);
  99
 100
 101static struct serial_state serial_state;
 102
 103/* some serial hardware definitions */
 104#define SDR_OVRUN   (1<<15)
 105#define SDR_RBF     (1<<14)
 106#define SDR_TBE     (1<<13)
 107#define SDR_TSRE    (1<<12)
 108
 109#define SERPER_PARENB    (1<<15)
 110
 111#define AC_SETCLR   (1<<15)
 112#define AC_UARTBRK  (1<<11)
 113
 114#define SER_DTR     (1<<7)
 115#define SER_RTS     (1<<6)
 116#define SER_DCD     (1<<5)
 117#define SER_CTS     (1<<4)
 118#define SER_DSR     (1<<3)
 119
 120static __inline__ void rtsdtr_ctrl(int bits)
 121{
 122    ciab.pra = ((bits & (SER_RTS | SER_DTR)) ^ (SER_RTS | SER_DTR)) | (ciab.pra & ~(SER_RTS | SER_DTR));
 123}
 124
 125/*
 126 * ------------------------------------------------------------
 127 * rs_stop() and rs_start()
 128 *
 129 * This routines are called before setting or resetting tty->flow.stopped.
 130 * They enable or disable transmitter interrupts, as necessary.
 131 * ------------------------------------------------------------
 132 */
 133static void rs_stop(struct tty_struct *tty)
 134{
 135	struct serial_state *info = tty->driver_data;
 136	unsigned long flags;
 137
 138	local_irq_save(flags);
 139	if (info->IER & UART_IER_THRI) {
 140		info->IER &= ~UART_IER_THRI;
 141		/* disable Tx interrupt and remove any pending interrupts */
 142		amiga_custom.intena = IF_TBE;
 143		mb();
 144		amiga_custom.intreq = IF_TBE;
 145		mb();
 146	}
 147	local_irq_restore(flags);
 148}
 149
 150static void rs_start(struct tty_struct *tty)
 151{
 152	struct serial_state *info = tty->driver_data;
 153	unsigned long flags;
 154
 155	local_irq_save(flags);
 156	if (info->xmit.head != info->xmit.tail
 157	    && info->xmit.buf
 158	    && !(info->IER & UART_IER_THRI)) {
 159		info->IER |= UART_IER_THRI;
 160		amiga_custom.intena = IF_SETCLR | IF_TBE;
 161		mb();
 162		/* set a pending Tx Interrupt, transmitter should restart now */
 163		amiga_custom.intreq = IF_SETCLR | IF_TBE;
 164		mb();
 165	}
 166	local_irq_restore(flags);
 167}
 168
 169/*
 170 * ----------------------------------------------------------------------
 171 *
 172 * Here start the interrupt handling routines.
 173 *
 174 * -----------------------------------------------------------------------
 175 */
 176
 177static void receive_chars(struct serial_state *info)
 178{
 179        int status;
 180	int serdatr;
 181	u8 ch, flag;
 182	struct	async_icount *icount;
 183	bool overrun = false;
 184
 185	icount = &info->icount;
 186
 187	status = UART_LSR_DR; /* We obviously have a character! */
 188	serdatr = amiga_custom.serdatr;
 189	mb();
 190	amiga_custom.intreq = IF_RBF;
 191	mb();
 192
 193	if((serdatr & 0x1ff) == 0)
 194	    status |= UART_LSR_BI;
 195	if(serdatr & SDR_OVRUN)
 196	    status |= UART_LSR_OE;
 197
 198	ch = serdatr & 0xff;
 199	icount->rx++;
 200
 201#ifdef SERIAL_DEBUG_INTR
 202	printk("DR%02x:%02x...", ch, status);
 203#endif
 204	flag = TTY_NORMAL;
 205
 206	/*
 207	 * We don't handle parity or frame errors - but I have left
 208	 * the code in, since I'm not sure that the errors can't be
 209	 * detected.
 210	 */
 211
 212	if (status & (UART_LSR_BI | UART_LSR_PE |
 213		      UART_LSR_FE | UART_LSR_OE)) {
 214	  /*
 215	   * For statistics only
 216	   */
 217	  if (status & UART_LSR_BI) {
 218	    status &= ~(UART_LSR_FE | UART_LSR_PE);
 219	    icount->brk++;
 220	  } else if (status & UART_LSR_PE)
 221	    icount->parity++;
 222	  else if (status & UART_LSR_FE)
 223	    icount->frame++;
 224	  if (status & UART_LSR_OE)
 225	    icount->overrun++;
 226
 227	  /*
 228	   * Now check to see if character should be
 229	   * ignored, and mask off conditions which
 230	   * should be ignored.
 231	   */
 232	  if (status & info->ignore_status_mask)
 233		  return;
 234
 235	  status &= info->read_status_mask;
 236
 237	  if (status & (UART_LSR_BI)) {
 238#ifdef SERIAL_DEBUG_INTR
 239	    printk("handling break....");
 240#endif
 241	    flag = TTY_BREAK;
 242	    if (info->tport.flags & ASYNC_SAK)
 243	      do_SAK(info->tport.tty);
 244	  } else if (status & UART_LSR_PE)
 245	    flag = TTY_PARITY;
 246	  else if (status & UART_LSR_FE)
 247	    flag = TTY_FRAME;
 248	  if (status & UART_LSR_OE) {
 249	    /*
 250	     * Overrun is special, since it's
 251	     * reported immediately, and doesn't
 252	     * affect the current character
 253	     */
 254	     overrun = true;
 255	  }
 256	}
 257	tty_insert_flip_char(&info->tport, ch, flag);
 258	if (overrun)
 259		tty_insert_flip_char(&info->tport, 0, TTY_OVERRUN);
 260	tty_flip_buffer_push(&info->tport);
 
 
 261}
 262
 263static void transmit_chars(struct serial_state *info)
 264{
 265	amiga_custom.intreq = IF_TBE;
 266	mb();
 267	if (info->x_char) {
 268	        amiga_custom.serdat = info->x_char | 0x100;
 269		mb();
 270		info->icount.tx++;
 271		info->x_char = 0;
 272		return;
 273	}
 274	if (info->xmit.head == info->xmit.tail
 275	    || info->tport.tty->flow.stopped
 276	    || info->tport.tty->hw_stopped) {
 277		info->IER &= ~UART_IER_THRI;
 278	        amiga_custom.intena = IF_TBE;
 279		mb();
 280		return;
 281	}
 282
 283	amiga_custom.serdat = info->xmit.buf[info->xmit.tail++] | 0x100;
 284	mb();
 285	info->xmit.tail = info->xmit.tail & (UART_XMIT_SIZE - 1);
 286	info->icount.tx++;
 287
 288	if (CIRC_CNT(info->xmit.head,
 289		     info->xmit.tail,
 290		     UART_XMIT_SIZE) < WAKEUP_CHARS)
 291		tty_wakeup(info->tport.tty);
 292
 293#ifdef SERIAL_DEBUG_INTR
 294	printk("THRE...");
 295#endif
 296	if (info->xmit.head == info->xmit.tail) {
 297	        amiga_custom.intena = IF_TBE;
 298		mb();
 299		info->IER &= ~UART_IER_THRI;
 300	}
 301}
 302
 303static void check_modem_status(struct serial_state *info)
 304{
 305	struct tty_port *port = &info->tport;
 306	unsigned char status = ciab.pra & (SER_DCD | SER_CTS | SER_DSR);
 307	unsigned char dstatus;
 308	struct	async_icount *icount;
 309
 310	/* Determine bits that have changed */
 311	dstatus = status ^ current_ctl_bits;
 312	current_ctl_bits = status;
 313
 314	if (dstatus) {
 315		icount = &info->icount;
 316		/* update input line counters */
 317		if (dstatus & SER_DSR)
 318			icount->dsr++;
 319		if (dstatus & SER_DCD) {
 320			icount->dcd++;
 321		}
 322		if (dstatus & SER_CTS)
 323			icount->cts++;
 324		wake_up_interruptible(&port->delta_msr_wait);
 325	}
 326
 327	if (tty_port_check_carrier(port) && (dstatus & SER_DCD)) {
 328#if (defined(SERIAL_DEBUG_OPEN) || defined(SERIAL_DEBUG_INTR))
 329		printk("ttyS%d CD now %s...", info->line,
 330		       (!(status & SER_DCD)) ? "on" : "off");
 331#endif
 332		if (!(status & SER_DCD))
 333			wake_up_interruptible(&port->open_wait);
 334		else {
 335#ifdef SERIAL_DEBUG_OPEN
 336			printk("doing serial hangup...");
 337#endif
 338			if (port->tty)
 339				tty_hangup(port->tty);
 340		}
 341	}
 342	if (tty_port_cts_enabled(port)) {
 343		if (port->tty->hw_stopped) {
 344			if (!(status & SER_CTS)) {
 345#if (defined(SERIAL_DEBUG_INTR) || defined(SERIAL_DEBUG_FLOW))
 346				printk("CTS tx start...");
 347#endif
 348				port->tty->hw_stopped = false;
 349				info->IER |= UART_IER_THRI;
 350				amiga_custom.intena = IF_SETCLR | IF_TBE;
 351				mb();
 352				/* set a pending Tx Interrupt, transmitter should restart now */
 353				amiga_custom.intreq = IF_SETCLR | IF_TBE;
 354				mb();
 355				tty_wakeup(port->tty);
 356				return;
 357			}
 358		} else {
 359			if ((status & SER_CTS)) {
 360#if (defined(SERIAL_DEBUG_INTR) || defined(SERIAL_DEBUG_FLOW))
 361				printk("CTS tx stop...");
 362#endif
 363				port->tty->hw_stopped = true;
 364				info->IER &= ~UART_IER_THRI;
 365				/* disable Tx interrupt and remove any pending interrupts */
 366				amiga_custom.intena = IF_TBE;
 367				mb();
 368				amiga_custom.intreq = IF_TBE;
 369				mb();
 370			}
 371		}
 372	}
 373}
 374
 375static irqreturn_t ser_vbl_int( int irq, void *data)
 376{
 377        /* vbl is just a periodic interrupt we tie into to update modem status */
 378	struct serial_state *info = data;
 379	/*
 380	 * TBD - is it better to unregister from this interrupt or to
 381	 * ignore it if MSI is clear ?
 382	 */
 383	if(info->IER & UART_IER_MSI)
 384	  check_modem_status(info);
 385	return IRQ_HANDLED;
 386}
 387
 388static irqreturn_t ser_rx_int(int irq, void *dev_id)
 389{
 390	struct serial_state *info = dev_id;
 391
 392#ifdef SERIAL_DEBUG_INTR
 393	printk("ser_rx_int...");
 394#endif
 395
 396	if (!info->tport.tty)
 397		return IRQ_NONE;
 398
 399	receive_chars(info);
 400#ifdef SERIAL_DEBUG_INTR
 401	printk("end.\n");
 402#endif
 403	return IRQ_HANDLED;
 404}
 405
 406static irqreturn_t ser_tx_int(int irq, void *dev_id)
 407{
 408	struct serial_state *info = dev_id;
 409
 410	if (amiga_custom.serdatr & SDR_TBE) {
 411#ifdef SERIAL_DEBUG_INTR
 412	  printk("ser_tx_int...");
 413#endif
 414
 415	  if (!info->tport.tty)
 416		return IRQ_NONE;
 417
 418	  transmit_chars(info);
 419#ifdef SERIAL_DEBUG_INTR
 420	  printk("end.\n");
 421#endif
 422	}
 423	return IRQ_HANDLED;
 424}
 425
 426/*
 427 * -------------------------------------------------------------------
 428 * Here ends the serial interrupt routines.
 429 * -------------------------------------------------------------------
 430 */
 431
 432/*
 433 * ---------------------------------------------------------------
 434 * Low level utility subroutines for the serial driver:  routines to
 435 * figure out the appropriate timeout for an interrupt chain, routines
 436 * to initialize and startup a serial port, and routines to shutdown a
 437 * serial port.  Useful stuff like that.
 438 * ---------------------------------------------------------------
 439 */
 440
 441static int startup(struct tty_struct *tty, struct serial_state *info)
 442{
 443	struct tty_port *port = &info->tport;
 444	unsigned long flags;
 445	int	retval=0;
 446	unsigned long page;
 447
 448	page = get_zeroed_page(GFP_KERNEL);
 449	if (!page)
 450		return -ENOMEM;
 451
 452	local_irq_save(flags);
 453
 454	if (tty_port_initialized(port)) {
 455		free_page(page);
 456		goto errout;
 457	}
 458
 459	if (info->xmit.buf)
 460		free_page(page);
 461	else
 462		info->xmit.buf = (unsigned char *) page;
 463
 464#ifdef SERIAL_DEBUG_OPEN
 465	printk("starting up ttys%d ...", info->line);
 466#endif
 467
 468	/* Clear anything in the input buffer */
 469
 470	amiga_custom.intreq = IF_RBF;
 471	mb();
 472
 473	retval = request_irq(IRQ_AMIGA_VERTB, ser_vbl_int, 0, "serial status", info);
 474	if (retval) {
 475		if (capable(CAP_SYS_ADMIN)) {
 476			set_bit(TTY_IO_ERROR, &tty->flags);
 477			retval = 0;
 478		}
 479		goto errout;
 480	}
 481
 482	/* enable both Rx and Tx interrupts */
 483	amiga_custom.intena = IF_SETCLR | IF_RBF | IF_TBE;
 484	mb();
 485	info->IER = UART_IER_MSI;
 486
 487	/* remember current state of the DCD and CTS bits */
 488	current_ctl_bits = ciab.pra & (SER_DCD | SER_CTS | SER_DSR);
 489
 490	info->MCR = 0;
 491	if (C_BAUD(tty))
 492	  info->MCR = SER_DTR | SER_RTS;
 493	rtsdtr_ctrl(info->MCR);
 494
 495	clear_bit(TTY_IO_ERROR, &tty->flags);
 496	info->xmit.head = info->xmit.tail = 0;
 497
 498	/*
 499	 * and set the speed of the serial port
 500	 */
 501	change_speed(tty, info, NULL);
 502
 503	tty_port_set_initialized(port, true);
 504	local_irq_restore(flags);
 505	return 0;
 506
 507errout:
 508	local_irq_restore(flags);
 509	return retval;
 510}
 511
 512/*
 513 * This routine will shutdown a serial port; interrupts are disabled, and
 514 * DTR is dropped if the hangup on close termio flag is on.
 515 */
 516static void shutdown(struct tty_struct *tty, struct serial_state *info)
 517{
 518	unsigned long	flags;
 519
 520	if (!tty_port_initialized(&info->tport))
 521		return;
 522
 523#ifdef SERIAL_DEBUG_OPEN
 524	printk("Shutting down serial port %d ....\n", info->line);
 525#endif
 526
 527	local_irq_save(flags); /* Disable interrupts */
 528
 529	/*
 530	 * clear delta_msr_wait queue to avoid mem leaks: we may free the irq
 531	 * here so the queue might never be waken up
 532	 */
 533	wake_up_interruptible(&info->tport.delta_msr_wait);
 534
 535	/*
 536	 * Free the IRQ, if necessary
 537	 */
 538	free_irq(IRQ_AMIGA_VERTB, info);
 539
 540	free_page((unsigned long)info->xmit.buf);
 541	info->xmit.buf = NULL;
 542
 543	info->IER = 0;
 544	amiga_custom.intena = IF_RBF | IF_TBE;
 545	mb();
 546
 547	/* disable break condition */
 548	amiga_custom.adkcon = AC_UARTBRK;
 549	mb();
 550
 551	if (C_HUPCL(tty))
 552		info->MCR &= ~(SER_DTR|SER_RTS);
 553	rtsdtr_ctrl(info->MCR);
 554
 555	set_bit(TTY_IO_ERROR, &tty->flags);
 556
 557	tty_port_set_initialized(&info->tport, false);
 558	local_irq_restore(flags);
 559}
 560
 561
 562/*
 563 * This routine is called to set the UART divisor registers to match
 564 * the specified baud rate for a serial port.
 565 */
 566static void change_speed(struct tty_struct *tty, struct serial_state *info,
 567			 const struct ktermios *old_termios)
 568{
 569	struct tty_port *port = &info->tport;
 570	int	quot = 0, baud_base, baud;
 571	unsigned cflag, cval = 0;
 572	int	bits;
 573	unsigned long	flags;
 574
 575	cflag = tty->termios.c_cflag;
 576
 577	/* Byte size is always 8 bits plus parity bit if requested */
 578
 579	cval = 3; bits = 10;
 580	if (cflag & CSTOPB) {
 581		cval |= 0x04;
 582		bits++;
 583	}
 584	if (cflag & PARENB) {
 585		cval |= UART_LCR_PARITY;
 586		bits++;
 587	}
 588	if (!(cflag & PARODD))
 589		cval |= UART_LCR_EPAR;
 590	if (cflag & CMSPAR)
 591		cval |= UART_LCR_SPAR;
 592
 593	/* Determine divisor based on baud rate */
 594	baud = tty_get_baud_rate(tty);
 595	if (!baud)
 596		baud = 9600;	/* B0 transition handled in rs_set_termios */
 597	baud_base = info->baud_base;
 598	if (baud == 38400 && (port->flags & ASYNC_SPD_MASK) == ASYNC_SPD_CUST)
 599		quot = info->custom_divisor;
 600	else {
 601		if (baud == 134)
 602			/* Special case since 134 is really 134.5 */
 603			quot = (2*baud_base / 269);
 604		else if (baud)
 605			quot = baud_base / baud;
 606	}
 607	/* If the quotient is zero refuse the change */
 608	if (!quot && old_termios) {
 609		/* FIXME: Will need updating for new tty in the end */
 610		tty->termios.c_cflag &= ~CBAUD;
 611		tty->termios.c_cflag |= (old_termios->c_cflag & CBAUD);
 612		baud = tty_get_baud_rate(tty);
 613		if (!baud)
 614			baud = 9600;
 615		if (baud == 38400 &&
 616		    (port->flags & ASYNC_SPD_MASK) == ASYNC_SPD_CUST)
 617			quot = info->custom_divisor;
 618		else {
 619			if (baud == 134)
 620				/* Special case since 134 is really 134.5 */
 621				quot = (2*baud_base / 269);
 622			else if (baud)
 623				quot = baud_base / baud;
 624		}
 625	}
 626	/* As a last resort, if the quotient is zero, default to 9600 bps */
 627	if (!quot)
 628		quot = baud_base / 9600;
 629	info->quot = quot;
 630	info->timeout = (XMIT_FIFO_SIZE*HZ*bits*quot) / baud_base;
 631	info->timeout += HZ/50;		/* Add .02 seconds of slop */
 632
 633	/* CTS flow control flag and modem status interrupts */
 634	info->IER &= ~UART_IER_MSI;
 635	if (port->flags & ASYNC_HARDPPS_CD)
 636		info->IER |= UART_IER_MSI;
 637	tty_port_set_cts_flow(port, cflag & CRTSCTS);
 638	if (cflag & CRTSCTS)
 639		info->IER |= UART_IER_MSI;
 640	tty_port_set_check_carrier(port, ~cflag & CLOCAL);
 641	if (~cflag & CLOCAL)
 642		info->IER |= UART_IER_MSI;
 643	/* TBD:
 644	 * Does clearing IER_MSI imply that we should disable the VBL interrupt ?
 645	 */
 646
 647	/*
 648	 * Set up parity check flag
 649	 */
 650
 651	info->read_status_mask = UART_LSR_OE | UART_LSR_DR;
 652	if (I_INPCK(tty))
 653		info->read_status_mask |= UART_LSR_FE | UART_LSR_PE;
 654	if (I_BRKINT(tty) || I_PARMRK(tty))
 655		info->read_status_mask |= UART_LSR_BI;
 656
 657	/*
 658	 * Characters to ignore
 659	 */
 660	info->ignore_status_mask = 0;
 661	if (I_IGNPAR(tty))
 662		info->ignore_status_mask |= UART_LSR_PE | UART_LSR_FE;
 663	if (I_IGNBRK(tty)) {
 664		info->ignore_status_mask |= UART_LSR_BI;
 665		/*
 666		 * If we're ignore parity and break indicators, ignore 
 667		 * overruns too.  (For real raw support).
 668		 */
 669		if (I_IGNPAR(tty))
 670			info->ignore_status_mask |= UART_LSR_OE;
 671	}
 672	/*
 673	 * !!! ignore all characters if CREAD is not set
 674	 */
 675	if ((cflag & CREAD) == 0)
 676		info->ignore_status_mask |= UART_LSR_DR;
 677	local_irq_save(flags);
 678
 679	{
 680	  short serper;
 681
 682	/* Set up the baud rate */
 683	  serper = quot - 1;
 684
 685	/* Enable or disable parity bit */
 686
 687	if(cval & UART_LCR_PARITY)
 688	  serper |= (SERPER_PARENB);
 689
 690	amiga_custom.serper = serper;
 691	mb();
 692	}
 693
 694	local_irq_restore(flags);
 695}
 696
 697static int rs_put_char(struct tty_struct *tty, u8 ch)
 698{
 699	struct serial_state *info;
 700	unsigned long flags;
 701
 702	info = tty->driver_data;
 703
 704	if (!info->xmit.buf)
 705		return 0;
 706
 707	local_irq_save(flags);
 708	if (CIRC_SPACE(info->xmit.head,
 709		       info->xmit.tail,
 710		       UART_XMIT_SIZE) == 0) {
 711		local_irq_restore(flags);
 712		return 0;
 713	}
 714
 715	info->xmit.buf[info->xmit.head++] = ch;
 716	info->xmit.head &= UART_XMIT_SIZE - 1;
 717	local_irq_restore(flags);
 718	return 1;
 719}
 720
 721static void rs_flush_chars(struct tty_struct *tty)
 722{
 723	struct serial_state *info = tty->driver_data;
 724	unsigned long flags;
 725
 726	if (info->xmit.head == info->xmit.tail
 727	    || tty->flow.stopped
 728	    || tty->hw_stopped
 729	    || !info->xmit.buf)
 730		return;
 731
 732	local_irq_save(flags);
 733	info->IER |= UART_IER_THRI;
 734	amiga_custom.intena = IF_SETCLR | IF_TBE;
 735	mb();
 736	/* set a pending Tx Interrupt, transmitter should restart now */
 737	amiga_custom.intreq = IF_SETCLR | IF_TBE;
 738	mb();
 739	local_irq_restore(flags);
 740}
 741
 742static ssize_t rs_write(struct tty_struct * tty, const u8 *buf, size_t count)
 743{
 744	int	c, ret = 0;
 745	struct serial_state *info = tty->driver_data;
 746	unsigned long flags;
 747
 748	if (!info->xmit.buf)
 749		return 0;
 750
 751	local_irq_save(flags);
 752	while (1) {
 753		c = CIRC_SPACE_TO_END(info->xmit.head,
 754				      info->xmit.tail,
 755				      UART_XMIT_SIZE);
 756		if (count < c)
 757			c = count;
 758		if (c <= 0) {
 759			break;
 760		}
 761		memcpy(info->xmit.buf + info->xmit.head, buf, c);
 762		info->xmit.head = (info->xmit.head + c) & (UART_XMIT_SIZE - 1);
 763		buf += c;
 764		count -= c;
 765		ret += c;
 766	}
 767	local_irq_restore(flags);
 768
 769	if (info->xmit.head != info->xmit.tail
 770	    && !tty->flow.stopped
 771	    && !tty->hw_stopped
 772	    && !(info->IER & UART_IER_THRI)) {
 773		info->IER |= UART_IER_THRI;
 774		local_irq_disable();
 775		amiga_custom.intena = IF_SETCLR | IF_TBE;
 776		mb();
 777		/* set a pending Tx Interrupt, transmitter should restart now */
 778		amiga_custom.intreq = IF_SETCLR | IF_TBE;
 779		mb();
 780		local_irq_restore(flags);
 781	}
 782	return ret;
 783}
 784
 785static unsigned int rs_write_room(struct tty_struct *tty)
 786{
 787	struct serial_state *info = tty->driver_data;
 788
 789	return CIRC_SPACE(info->xmit.head, info->xmit.tail, UART_XMIT_SIZE);
 790}
 791
 792static unsigned int rs_chars_in_buffer(struct tty_struct *tty)
 793{
 794	struct serial_state *info = tty->driver_data;
 795
 796	return CIRC_CNT(info->xmit.head, info->xmit.tail, UART_XMIT_SIZE);
 797}
 798
 799static void rs_flush_buffer(struct tty_struct *tty)
 800{
 801	struct serial_state *info = tty->driver_data;
 802	unsigned long flags;
 803
 804	local_irq_save(flags);
 805	info->xmit.head = info->xmit.tail = 0;
 806	local_irq_restore(flags);
 807	tty_wakeup(tty);
 808}
 809
 810/*
 811 * This function is used to send a high-priority XON/XOFF character to
 812 * the device
 813 */
 814static void rs_send_xchar(struct tty_struct *tty, u8 ch)
 815{
 816	struct serial_state *info = tty->driver_data;
 817        unsigned long flags;
 818
 819	info->x_char = ch;
 820	if (ch) {
 821		/* Make sure transmit interrupts are on */
 822
 823	        /* Check this ! */
 824	        local_irq_save(flags);
 825		if(!(amiga_custom.intenar & IF_TBE)) {
 826		    amiga_custom.intena = IF_SETCLR | IF_TBE;
 827		    mb();
 828		    /* set a pending Tx Interrupt, transmitter should restart now */
 829		    amiga_custom.intreq = IF_SETCLR | IF_TBE;
 830		    mb();
 831		}
 832		local_irq_restore(flags);
 833
 834		info->IER |= UART_IER_THRI;
 835	}
 836}
 837
 838/*
 839 * ------------------------------------------------------------
 840 * rs_throttle()
 841 * 
 842 * This routine is called by the upper-layer tty layer to signal that
 843 * incoming characters should be throttled.
 844 * ------------------------------------------------------------
 845 */
 846static void rs_throttle(struct tty_struct * tty)
 847{
 848	struct serial_state *info = tty->driver_data;
 849	unsigned long flags;
 850#ifdef SERIAL_DEBUG_THROTTLE
 851	printk("throttle %s ....\n", tty_name(tty));
 852#endif
 853
 854	if (I_IXOFF(tty))
 855		rs_send_xchar(tty, STOP_CHAR(tty));
 856
 857	if (C_CRTSCTS(tty))
 858		info->MCR &= ~SER_RTS;
 859
 860	local_irq_save(flags);
 861	rtsdtr_ctrl(info->MCR);
 862	local_irq_restore(flags);
 863}
 864
 865static void rs_unthrottle(struct tty_struct * tty)
 866{
 867	struct serial_state *info = tty->driver_data;
 868	unsigned long flags;
 869#ifdef SERIAL_DEBUG_THROTTLE
 870	printk("unthrottle %s ....\n", tty_name(tty));
 871#endif
 872
 873	if (I_IXOFF(tty)) {
 874		if (info->x_char)
 875			info->x_char = 0;
 876		else
 877			rs_send_xchar(tty, START_CHAR(tty));
 878	}
 879	if (C_CRTSCTS(tty))
 880		info->MCR |= SER_RTS;
 881	local_irq_save(flags);
 882	rtsdtr_ctrl(info->MCR);
 883	local_irq_restore(flags);
 884}
 885
 886/*
 887 * ------------------------------------------------------------
 888 * rs_ioctl() and friends
 889 * ------------------------------------------------------------
 890 */
 891
 892static int get_serial_info(struct tty_struct *tty, struct serial_struct *ss)
 893{
 894	struct serial_state *state = tty->driver_data;
 895	unsigned int close_delay, closing_wait;
 896
 897	tty_lock(tty);
 898	close_delay = jiffies_to_msecs(state->tport.close_delay) / 10;
 899	closing_wait = state->tport.closing_wait;
 900	if (closing_wait != ASYNC_CLOSING_WAIT_NONE)
 901		closing_wait = jiffies_to_msecs(closing_wait) / 10;
 902
 903	ss->line = tty->index;
 904	ss->port = state->port;
 905	ss->flags = state->tport.flags;
 906	ss->xmit_fifo_size = XMIT_FIFO_SIZE;
 907	ss->baud_base = state->baud_base;
 908	ss->close_delay = close_delay;
 909	ss->closing_wait = closing_wait;
 910	ss->custom_divisor = state->custom_divisor;
 911	tty_unlock(tty);
 912	return 0;
 913}
 914
 915static int set_serial_info(struct tty_struct *tty, struct serial_struct *ss)
 916{
 917	struct serial_state *state = tty->driver_data;
 918	struct tty_port *port = &state->tport;
 919	bool change_spd;
 920	int 			retval = 0;
 921	unsigned int close_delay, closing_wait;
 922
 923	tty_lock(tty);
 924	change_spd = ((ss->flags ^ port->flags) & ASYNC_SPD_MASK) ||
 925		ss->custom_divisor != state->custom_divisor;
 926	if (ss->irq || ss->port != state->port ||
 927			ss->xmit_fifo_size != XMIT_FIFO_SIZE) {
 928		tty_unlock(tty);
 929		return -EINVAL;
 930	}
 931
 932	close_delay = msecs_to_jiffies(ss->close_delay * 10);
 933	closing_wait = ss->closing_wait;
 934	if (closing_wait != ASYNC_CLOSING_WAIT_NONE)
 935		closing_wait = msecs_to_jiffies(closing_wait * 10);
 936
 937	if (!capable(CAP_SYS_ADMIN)) {
 938		if ((ss->baud_base != state->baud_base) ||
 939		    (close_delay != port->close_delay) ||
 940		    (closing_wait != port->closing_wait) ||
 941		    ((ss->flags & ~ASYNC_USR_MASK) !=
 942		     (port->flags & ~ASYNC_USR_MASK))) {
 943			tty_unlock(tty);
 944			return -EPERM;
 945		}
 946		port->flags = ((port->flags & ~ASYNC_USR_MASK) |
 947			       (ss->flags & ASYNC_USR_MASK));
 948		state->custom_divisor = ss->custom_divisor;
 949		goto check_and_exit;
 950	}
 951
 952	if (ss->baud_base < 9600) {
 953		tty_unlock(tty);
 954		return -EINVAL;
 955	}
 956
 957	/*
 958	 * OK, past this point, all the error checking has been done.
 959	 * At this point, we start making changes.....
 960	 */
 961
 962	state->baud_base = ss->baud_base;
 963	port->flags = ((port->flags & ~ASYNC_FLAGS) |
 964			(ss->flags & ASYNC_FLAGS));
 965	state->custom_divisor = ss->custom_divisor;
 966	port->close_delay = close_delay;
 967	port->closing_wait = closing_wait;
 968
 969check_and_exit:
 970	if (tty_port_initialized(port)) {
 971		if (change_spd) {
 972			/* warn about deprecation unless clearing */
 973			if (ss->flags & ASYNC_SPD_MASK)
 974				dev_warn_ratelimited(tty->dev, "use of SPD flags is deprecated\n");
 975			change_speed(tty, state, NULL);
 976		}
 977	} else
 978		retval = startup(tty, state);
 979	tty_unlock(tty);
 980	return retval;
 981}
 982
 983/*
 984 * get_lsr_info - get line status register info
 985 *
 986 * Purpose: Let user call ioctl() to get info when the UART physically
 987 * 	    is emptied.  On bus types like RS485, the transmitter must
 988 * 	    release the bus after transmitting. This must be done when
 989 * 	    the transmit shift register is empty, not be done when the
 990 * 	    transmit holding register is empty.  This functionality
 991 * 	    allows an RS485 driver to be written in user space. 
 992 */
 993static int get_lsr_info(struct serial_state *info, unsigned int __user *value)
 994{
 995	unsigned char status;
 996	unsigned int result;
 997	unsigned long flags;
 998
 999	local_irq_save(flags);
1000	status = amiga_custom.serdatr;
1001	mb();
1002	local_irq_restore(flags);
1003	result = ((status & SDR_TSRE) ? TIOCSER_TEMT : 0);
1004	if (copy_to_user(value, &result, sizeof(int)))
1005		return -EFAULT;
1006	return 0;
1007}
1008
1009
1010static int rs_tiocmget(struct tty_struct *tty)
1011{
1012	struct serial_state *info = tty->driver_data;
1013	unsigned char control, status;
1014	unsigned long flags;
1015
1016	if (tty_io_error(tty))
1017		return -EIO;
1018
1019	control = info->MCR;
1020	local_irq_save(flags);
1021	status = ciab.pra;
1022	local_irq_restore(flags);
1023	return    ((control & SER_RTS) ? TIOCM_RTS : 0)
1024		| ((control & SER_DTR) ? TIOCM_DTR : 0)
1025		| (!(status  & SER_DCD) ? TIOCM_CAR : 0)
1026		| (!(status  & SER_DSR) ? TIOCM_DSR : 0)
1027		| (!(status  & SER_CTS) ? TIOCM_CTS : 0);
1028}
1029
1030static int rs_tiocmset(struct tty_struct *tty, unsigned int set,
1031						unsigned int clear)
1032{
1033	struct serial_state *info = tty->driver_data;
1034	unsigned long flags;
1035
1036	if (tty_io_error(tty))
1037		return -EIO;
1038
1039	local_irq_save(flags);
1040	if (set & TIOCM_RTS)
1041		info->MCR |= SER_RTS;
1042	if (set & TIOCM_DTR)
1043		info->MCR |= SER_DTR;
1044	if (clear & TIOCM_RTS)
1045		info->MCR &= ~SER_RTS;
1046	if (clear & TIOCM_DTR)
1047		info->MCR &= ~SER_DTR;
1048	rtsdtr_ctrl(info->MCR);
1049	local_irq_restore(flags);
1050	return 0;
1051}
1052
1053/*
1054 * rs_break() --- routine which turns the break handling on or off
1055 */
1056static int rs_break(struct tty_struct *tty, int break_state)
1057{
1058	unsigned long flags;
1059
1060	local_irq_save(flags);
1061	if (break_state == -1)
1062	  amiga_custom.adkcon = AC_SETCLR | AC_UARTBRK;
1063	else
1064	  amiga_custom.adkcon = AC_UARTBRK;
1065	mb();
1066	local_irq_restore(flags);
1067	return 0;
1068}
1069
1070/*
1071 * Get counter of input serial line interrupts (DCD,RI,DSR,CTS)
1072 * Return: write counters to the user passed counter struct
1073 * NB: both 1->0 and 0->1 transitions are counted except for
1074 *     RI where only 0->1 is counted.
1075 */
1076static int rs_get_icount(struct tty_struct *tty,
1077				struct serial_icounter_struct *icount)
1078{
1079	struct serial_state *info = tty->driver_data;
1080	struct async_icount cnow;
1081	unsigned long flags;
1082
1083	local_irq_save(flags);
1084	cnow = info->icount;
1085	local_irq_restore(flags);
1086	icount->cts = cnow.cts;
1087	icount->dsr = cnow.dsr;
1088	icount->rng = cnow.rng;
1089	icount->dcd = cnow.dcd;
1090	icount->rx = cnow.rx;
1091	icount->tx = cnow.tx;
1092	icount->frame = cnow.frame;
1093	icount->overrun = cnow.overrun;
1094	icount->parity = cnow.parity;
1095	icount->brk = cnow.brk;
1096	icount->buf_overrun = cnow.buf_overrun;
1097
1098	return 0;
1099}
1100
1101static int rs_ioctl(struct tty_struct *tty,
1102		    unsigned int cmd, unsigned long arg)
1103{
1104	struct serial_state *info = tty->driver_data;
1105	struct async_icount cprev, cnow;	/* kernel counter temps */
1106	void __user *argp = (void __user *)arg;
1107	unsigned long flags;
1108	DEFINE_WAIT(wait);
1109	int ret;
1110
1111	if ((cmd != TIOCSERCONFIG) &&
1112	    (cmd != TIOCMIWAIT) && (cmd != TIOCGICOUNT)) {
1113		if (tty_io_error(tty))
1114		    return -EIO;
1115	}
1116
1117	switch (cmd) {
1118		case TIOCSERCONFIG:
1119			return 0;
1120
1121		case TIOCSERGETLSR: /* Get line status register */
1122			return get_lsr_info(info, argp);
1123
1124		/*
1125		 * Wait for any of the 4 modem inputs (DCD,RI,DSR,CTS) to change
1126		 * - mask passed in arg for lines of interest
1127 		 *   (use |'ed TIOCM_RNG/DSR/CD/CTS for masking)
1128		 * Caller should use TIOCGICOUNT to see which one it was
1129		 */
1130		case TIOCMIWAIT:
1131			local_irq_save(flags);
1132			/* note the counters on entry */
1133			cprev = info->icount;
1134			local_irq_restore(flags);
1135			while (1) {
1136				prepare_to_wait(&info->tport.delta_msr_wait,
1137						&wait, TASK_INTERRUPTIBLE);
1138				local_irq_save(flags);
1139				cnow = info->icount; /* atomic copy */
1140				local_irq_restore(flags);
1141				if (cnow.rng == cprev.rng && cnow.dsr == cprev.dsr && 
1142				    cnow.dcd == cprev.dcd && cnow.cts == cprev.cts) {
1143					ret = -EIO; /* no change => error */
1144					break;
1145				}
1146				if ( ((arg & TIOCM_RNG) && (cnow.rng != cprev.rng)) ||
1147				     ((arg & TIOCM_DSR) && (cnow.dsr != cprev.dsr)) ||
1148				     ((arg & TIOCM_CD)  && (cnow.dcd != cprev.dcd)) ||
1149				     ((arg & TIOCM_CTS) && (cnow.cts != cprev.cts)) ) {
1150					ret = 0;
1151					break;
1152				}
1153				schedule();
1154				/* see if a signal did it */
1155				if (signal_pending(current)) {
1156					ret = -ERESTARTSYS;
1157					break;
1158				}
1159				cprev = cnow;
1160			}
1161			finish_wait(&info->tport.delta_msr_wait, &wait);
1162			return ret;
1163
1164		default:
1165			return -ENOIOCTLCMD;
1166		}
1167	return 0;
1168}
1169
1170static void rs_set_termios(struct tty_struct *tty, const struct ktermios *old_termios)
1171{
1172	struct serial_state *info = tty->driver_data;
1173	unsigned long flags;
1174	unsigned int cflag = tty->termios.c_cflag;
1175
1176	change_speed(tty, info, old_termios);
1177
1178	/* Handle transition to B0 status */
1179	if ((old_termios->c_cflag & CBAUD) && !(cflag & CBAUD)) {
1180		info->MCR &= ~(SER_DTR|SER_RTS);
1181		local_irq_save(flags);
1182		rtsdtr_ctrl(info->MCR);
1183		local_irq_restore(flags);
1184	}
1185
1186	/* Handle transition away from B0 status */
1187	if (!(old_termios->c_cflag & CBAUD) && (cflag & CBAUD)) {
1188		info->MCR |= SER_DTR;
1189		if (!C_CRTSCTS(tty) || !tty_throttled(tty))
1190			info->MCR |= SER_RTS;
1191		local_irq_save(flags);
1192		rtsdtr_ctrl(info->MCR);
1193		local_irq_restore(flags);
1194	}
1195
1196	/* Handle turning off CRTSCTS */
1197	if ((old_termios->c_cflag & CRTSCTS) && !C_CRTSCTS(tty)) {
1198		tty->hw_stopped = false;
1199		rs_start(tty);
1200	}
1201
1202#if 0
1203	/*
1204	 * No need to wake up processes in open wait, since they
1205	 * sample the CLOCAL flag once, and don't recheck it.
1206	 * XXX  It's not clear whether the current behavior is correct
1207	 * or not.  Hence, this may change.....
1208	 */
1209	if (!(old_termios->c_cflag & CLOCAL) && C_CLOCAL(tty))
1210		wake_up_interruptible(&info->open_wait);
1211#endif
1212}
1213
1214/*
1215 * ------------------------------------------------------------
1216 * rs_close()
1217 * 
1218 * This routine is called when the serial port gets closed.  First, we
1219 * wait for the last remaining data to be sent.  Then, we unlink its
1220 * async structure from the interrupt chain if necessary, and we free
1221 * that IRQ if nothing is left in the chain.
1222 * ------------------------------------------------------------
1223 */
1224static void rs_close(struct tty_struct *tty, struct file * filp)
1225{
1226	struct serial_state *state = tty->driver_data;
1227	struct tty_port *port = &state->tport;
1228
1229	if (tty_port_close_start(port, tty, filp) == 0)
1230		return;
1231
1232	/*
1233	 * At this point we stop accepting input.  To do this, we
1234	 * disable the receive line status interrupts, and tell the
1235	 * interrupt driver to stop checking the data ready bit in the
1236	 * line status register.
1237	 */
1238	state->read_status_mask &= ~UART_LSR_DR;
1239	if (tty_port_initialized(port)) {
1240	        /* disable receive interrupts */
1241	        amiga_custom.intena = IF_RBF;
1242		mb();
1243		/* clear any pending receive interrupt */
1244		amiga_custom.intreq = IF_RBF;
1245		mb();
1246
1247		/*
1248		 * Before we drop DTR, make sure the UART transmitter
1249		 * has completely drained; this is especially
1250		 * important if there is a transmit FIFO!
1251		 */
1252		rs_wait_until_sent(tty, state->timeout);
1253	}
1254	shutdown(tty, state);
1255	rs_flush_buffer(tty);
1256		
1257	tty_ldisc_flush(tty);
1258	port->tty = NULL;
1259
1260	tty_port_close_end(port, tty);
1261}
1262
1263/*
1264 * rs_wait_until_sent() --- wait until the transmitter is empty
1265 */
1266static void rs_wait_until_sent(struct tty_struct *tty, int timeout)
1267{
1268	struct serial_state *info = tty->driver_data;
1269	unsigned long orig_jiffies, char_time;
1270	int lsr;
1271
1272	orig_jiffies = jiffies;
1273
1274	/*
1275	 * Set the check interval to be 1/5 of the estimated time to
1276	 * send a single character, and make it at least 1.  The check
1277	 * interval should also be less than the timeout.
1278	 * 
1279	 * Note: we have to use pretty tight timings here to satisfy
1280	 * the NIST-PCTS.
1281	 */
1282	char_time = (info->timeout - HZ/50) / XMIT_FIFO_SIZE;
1283	char_time = char_time / 5;
1284	if (char_time == 0)
1285		char_time = 1;
1286	if (timeout)
1287	  char_time = min_t(unsigned long, char_time, timeout);
1288	/*
1289	 * If the transmitter hasn't cleared in twice the approximate
1290	 * amount of time to send the entire FIFO, it probably won't
1291	 * ever clear.  This assumes the UART isn't doing flow
1292	 * control, which is currently the case.  Hence, if it ever
1293	 * takes longer than info->timeout, this is probably due to a
1294	 * UART bug of some kind.  So, we clamp the timeout parameter at
1295	 * 2*info->timeout.
1296	 */
1297	if (!timeout || timeout > 2*info->timeout)
1298		timeout = 2*info->timeout;
1299#ifdef SERIAL_DEBUG_RS_WAIT_UNTIL_SENT
1300	printk("In rs_wait_until_sent(%d) check=%lu...", timeout, char_time);
1301	printk("jiff=%lu...", jiffies);
1302#endif
1303	while(!((lsr = amiga_custom.serdatr) & SDR_TSRE)) {
1304#ifdef SERIAL_DEBUG_RS_WAIT_UNTIL_SENT
1305		printk("serdatr = %d (jiff=%lu)...", lsr, jiffies);
1306#endif
1307		msleep_interruptible(jiffies_to_msecs(char_time));
1308		if (signal_pending(current))
1309			break;
1310		if (timeout && time_after(jiffies, orig_jiffies + timeout))
1311			break;
1312	}
1313	__set_current_state(TASK_RUNNING);
1314
1315#ifdef SERIAL_DEBUG_RS_WAIT_UNTIL_SENT
1316	printk("lsr = %d (jiff=%lu)...done\n", lsr, jiffies);
1317#endif
1318}
1319
1320/*
1321 * rs_hangup() --- called by tty_hangup() when a hangup is signaled.
1322 */
1323static void rs_hangup(struct tty_struct *tty)
1324{
1325	struct serial_state *info = tty->driver_data;
1326
1327	rs_flush_buffer(tty);
1328	shutdown(tty, info);
1329	info->tport.count = 0;
1330	tty_port_set_active(&info->tport, false);
1331	info->tport.tty = NULL;
1332	wake_up_interruptible(&info->tport.open_wait);
1333}
1334
1335/*
1336 * This routine is called whenever a serial port is opened.  It
1337 * enables interrupts for a serial port, linking in its async structure into
1338 * the IRQ chain.   It also performs the serial-specific
1339 * initialization for the tty structure.
1340 */
1341static int rs_open(struct tty_struct *tty, struct file * filp)
1342{
1343	struct tty_port *port = tty->port;
1344	struct serial_state *info = container_of(port, struct serial_state,
1345			tport);
1346	int retval;
1347
1348	port->count++;
1349	port->tty = tty;
1350	tty->driver_data = info;
1351
1352	retval = startup(tty, info);
1353	if (retval) {
1354		return retval;
1355	}
1356
1357	return tty_port_block_til_ready(port, tty, filp);
1358}
1359
1360/*
1361 * /proc fs routines....
1362 */
1363
1364static inline void line_info(struct seq_file *m, int line,
1365		struct serial_state *state)
1366{
1367	char	stat_buf[30], control, status;
1368	unsigned long flags;
1369
1370	seq_printf(m, "%d: uart:amiga_builtin", line);
1371
1372	local_irq_save(flags);
1373	status = ciab.pra;
1374	control = tty_port_initialized(&state->tport) ? state->MCR : status;
1375	local_irq_restore(flags);
1376
1377	stat_buf[0] = 0;
1378	stat_buf[1] = 0;
1379	if(!(control & SER_RTS))
1380		strcat(stat_buf, "|RTS");
1381	if(!(status & SER_CTS))
1382		strcat(stat_buf, "|CTS");
1383	if(!(control & SER_DTR))
1384		strcat(stat_buf, "|DTR");
1385	if(!(status & SER_DSR))
1386		strcat(stat_buf, "|DSR");
1387	if(!(status & SER_DCD))
1388		strcat(stat_buf, "|CD");
1389
1390	if (state->quot)
1391		seq_printf(m, " baud:%d", state->baud_base / state->quot);
1392
1393	seq_printf(m, " tx:%d rx:%d", state->icount.tx, state->icount.rx);
1394
1395	if (state->icount.frame)
1396		seq_printf(m, " fe:%d", state->icount.frame);
1397
1398	if (state->icount.parity)
1399		seq_printf(m, " pe:%d", state->icount.parity);
1400
1401	if (state->icount.brk)
1402		seq_printf(m, " brk:%d", state->icount.brk);
1403
1404	if (state->icount.overrun)
1405		seq_printf(m, " oe:%d", state->icount.overrun);
1406
1407	/*
1408	 * Last thing is the RS-232 status lines
1409	 */
1410	seq_printf(m, " %s\n", stat_buf+1);
1411}
1412
1413static int rs_proc_show(struct seq_file *m, void *v)
1414{
1415	seq_printf(m, "serinfo:1.0 driver:4.30\n");
1416	line_info(m, 0, &serial_state);
1417	return 0;
1418}
1419
1420/*
1421 * ---------------------------------------------------------------------
1422 * rs_init() and friends
1423 *
1424 * rs_init() is called at boot-time to initialize the serial driver.
1425 * ---------------------------------------------------------------------
1426 */
1427
1428static const struct tty_operations serial_ops = {
1429	.open = rs_open,
1430	.close = rs_close,
1431	.write = rs_write,
1432	.put_char = rs_put_char,
1433	.flush_chars = rs_flush_chars,
1434	.write_room = rs_write_room,
1435	.chars_in_buffer = rs_chars_in_buffer,
1436	.flush_buffer = rs_flush_buffer,
1437	.ioctl = rs_ioctl,
1438	.throttle = rs_throttle,
1439	.unthrottle = rs_unthrottle,
1440	.set_termios = rs_set_termios,
1441	.stop = rs_stop,
1442	.start = rs_start,
1443	.hangup = rs_hangup,
1444	.break_ctl = rs_break,
1445	.send_xchar = rs_send_xchar,
1446	.wait_until_sent = rs_wait_until_sent,
1447	.tiocmget = rs_tiocmget,
1448	.tiocmset = rs_tiocmset,
1449	.get_icount = rs_get_icount,
1450	.set_serial = set_serial_info,
1451	.get_serial = get_serial_info,
1452	.proc_show = rs_proc_show,
1453};
1454
1455static bool amiga_carrier_raised(struct tty_port *port)
1456{
1457	return !(ciab.pra & SER_DCD);
1458}
1459
1460static void amiga_dtr_rts(struct tty_port *port, bool active)
1461{
1462	struct serial_state *info = container_of(port, struct serial_state,
1463			tport);
1464	unsigned long flags;
1465
1466	if (active)
1467		info->MCR |= SER_DTR|SER_RTS;
1468	else
1469		info->MCR &= ~(SER_DTR|SER_RTS);
1470
1471	local_irq_save(flags);
1472	rtsdtr_ctrl(info->MCR);
1473	local_irq_restore(flags);
1474}
1475
1476static const struct tty_port_operations amiga_port_ops = {
1477	.carrier_raised = amiga_carrier_raised,
1478	.dtr_rts = amiga_dtr_rts,
1479};
1480
1481/*
1482 * The serial driver boot-time initialization code!
1483 */
1484static int __init amiga_serial_probe(struct platform_device *pdev)
1485{
1486	struct serial_state *state = &serial_state;
1487	struct tty_driver *driver;
1488	unsigned long flags;
1489	int error;
1490
1491	driver = tty_alloc_driver(1, TTY_DRIVER_REAL_RAW);
1492	if (IS_ERR(driver))
1493		return PTR_ERR(driver);
1494
1495	/* Initialize the tty_driver structure */
1496
1497	driver->driver_name = "amiserial";
1498	driver->name = "ttyS";
1499	driver->major = TTY_MAJOR;
1500	driver->minor_start = 64;
1501	driver->type = TTY_DRIVER_TYPE_SERIAL;
1502	driver->subtype = SERIAL_TYPE_NORMAL;
1503	driver->init_termios = tty_std_termios;
1504	driver->init_termios.c_cflag =
1505		B9600 | CS8 | CREAD | HUPCL | CLOCAL;
1506	tty_set_operations(driver, &serial_ops);
1507
1508	memset(state, 0, sizeof(*state));
1509	state->port = (int)&amiga_custom.serdatr; /* Just to give it a value */
1510	tty_port_init(&state->tport);
1511	state->tport.ops = &amiga_port_ops;
1512	tty_port_link_device(&state->tport, driver, 0);
1513
1514	error = tty_register_driver(driver);
1515	if (error)
1516		goto fail_tty_driver_kref_put;
1517
1518	printk(KERN_INFO "ttyS0 is the amiga builtin serial port\n");
1519
1520	/* Hardware set up */
1521
1522	state->baud_base = amiga_colorclock;
1523
1524	/* set ISRs, and then disable the rx interrupts */
1525	error = request_irq(IRQ_AMIGA_TBE, ser_tx_int, 0, "serial TX", state);
1526	if (error)
1527		goto fail_unregister;
1528
1529	error = request_irq(IRQ_AMIGA_RBF, ser_rx_int, 0,
1530			    "serial RX", state);
1531	if (error)
1532		goto fail_free_irq;
1533
1534	local_irq_save(flags);
1535
1536	/* turn off Rx and Tx interrupts */
1537	amiga_custom.intena = IF_RBF | IF_TBE;
1538	mb();
1539
1540	/* clear any pending interrupt */
1541	amiga_custom.intreq = IF_RBF | IF_TBE;
1542	mb();
1543
1544	local_irq_restore(flags);
1545
1546	/*
1547	 * set the appropriate directions for the modem control flags,
1548	 * and clear RTS and DTR
1549	 */
1550	ciab.ddra |= (SER_DTR | SER_RTS);   /* outputs */
1551	ciab.ddra &= ~(SER_DCD | SER_CTS | SER_DSR);  /* inputs */
1552
1553	platform_set_drvdata(pdev, state);
1554
1555	serial_driver = driver;
1556
1557	return 0;
1558
1559fail_free_irq:
1560	free_irq(IRQ_AMIGA_TBE, state);
1561fail_unregister:
1562	tty_unregister_driver(driver);
1563fail_tty_driver_kref_put:
1564	tty_port_destroy(&state->tport);
1565	tty_driver_kref_put(driver);
1566	return error;
1567}
1568
1569static int __exit amiga_serial_remove(struct platform_device *pdev)
1570{
1571	struct serial_state *state = platform_get_drvdata(pdev);
1572
1573	tty_unregister_driver(serial_driver);
1574	tty_driver_kref_put(serial_driver);
1575	tty_port_destroy(&state->tport);
1576
1577	free_irq(IRQ_AMIGA_TBE, state);
1578	free_irq(IRQ_AMIGA_RBF, state);
1579
1580	return 0;
1581}
1582
1583static struct platform_driver amiga_serial_driver = {
1584	.remove = __exit_p(amiga_serial_remove),
1585	.driver   = {
1586		.name	= "amiga-serial",
1587	},
1588};
1589
1590module_platform_driver_probe(amiga_serial_driver, amiga_serial_probe);
1591
1592
1593#if defined(CONFIG_SERIAL_CONSOLE) && !defined(MODULE)
1594
1595/*
1596 * ------------------------------------------------------------
1597 * Serial console driver
1598 * ------------------------------------------------------------
1599 */
1600
1601static void amiga_serial_putc(char c)
1602{
1603	amiga_custom.serdat = (unsigned char)c | 0x100;
1604	while (!(amiga_custom.serdatr & 0x2000))
1605		barrier();
1606}
1607
1608/*
1609 *	Print a string to the serial port trying not to disturb
1610 *	any possible real use of the port...
1611 *
1612 *	The console must be locked when we get here.
1613 */
1614static void serial_console_write(struct console *co, const char *s,
1615				unsigned count)
1616{
1617	unsigned short intena = amiga_custom.intenar;
1618
1619	amiga_custom.intena = IF_TBE;
1620
1621	while (count--) {
1622		if (*s == '\n')
1623			amiga_serial_putc('\r');
1624		amiga_serial_putc(*s++);
1625	}
1626
1627	amiga_custom.intena = IF_SETCLR | (intena & IF_TBE);
1628}
1629
1630static struct tty_driver *serial_console_device(struct console *c, int *index)
1631{
1632	*index = 0;
1633	return serial_driver;
1634}
1635
1636static struct console sercons = {
1637	.name =		"ttyS",
1638	.write =	serial_console_write,
1639	.device =	serial_console_device,
1640	.flags =	CON_PRINTBUFFER,
1641	.index =	-1,
1642};
1643
1644/*
1645 *	Register console.
1646 */
1647static int __init amiserial_console_init(void)
1648{
1649	if (!MACH_IS_AMIGA)
1650		return -ENODEV;
1651
1652	register_console(&sercons);
1653	return 0;
1654}
1655console_initcall(amiserial_console_init);
1656
1657#endif /* CONFIG_SERIAL_CONSOLE && !MODULE */
1658
1659MODULE_LICENSE("GPL");
1660MODULE_ALIAS("platform:amiga-serial");