Linux Audio

Check our new training course

Loading...
Note: File does not exist in v5.4.
   1/* 68328serial.c: Serial port driver for 68328 microcontroller
   2 *
   3 * Copyright (C) 1995       David S. Miller    <davem@caip.rutgers.edu>
   4 * Copyright (C) 1998       Kenneth Albanowski <kjahds@kjahds.com>
   5 * Copyright (C) 1998, 1999 D. Jeff Dionne     <jeff@uclinux.org>
   6 * Copyright (C) 1999       Vladimir Gurevich  <vgurevic@cisco.com>
   7 * Copyright (C) 2002-2003  David McCullough   <davidm@snapgear.com>
   8 * Copyright (C) 2002       Greg Ungerer       <gerg@snapgear.com>
   9 *
  10 * VZ Support/Fixes             Evan Stawnyczy <e@lineo.ca>
  11 * Multiple UART support        Daniel Potts <danielp@cse.unsw.edu.au>
  12 * Power management support     Daniel Potts <danielp@cse.unsw.edu.au>
  13 * VZ Second Serial Port enable Phil Wilshire
  14 * 2.4/2.5 port                 David McCullough
  15 */
  16
  17#include <linux/module.h>
  18#include <linux/errno.h>
  19#include <linux/serial.h>
  20#include <linux/signal.h>
  21#include <linux/sched.h>
  22#include <linux/timer.h>
  23#include <linux/interrupt.h>
  24#include <linux/tty.h>
  25#include <linux/tty_flip.h>
  26#include <linux/major.h>
  27#include <linux/string.h>
  28#include <linux/fcntl.h>
  29#include <linux/mm.h>
  30#include <linux/kernel.h>
  31#include <linux/console.h>
  32#include <linux/reboot.h>
  33#include <linux/keyboard.h>
  34#include <linux/init.h>
  35#include <linux/pm.h>
  36#include <linux/bitops.h>
  37#include <linux/delay.h>
  38#include <linux/gfp.h>
  39
  40#include <asm/io.h>
  41#include <asm/irq.h>
  42#include <asm/delay.h>
  43#include <asm/uaccess.h>
  44
  45/* (es) */
  46/* note: perhaps we can murge these files, so that you can just
  47 * 	 define 1 of them, and they can sort that out for themselves
  48 */
  49#if defined(CONFIG_M68EZ328)
  50#include <asm/MC68EZ328.h>
  51#else
  52#if defined(CONFIG_M68VZ328)
  53#include <asm/MC68VZ328.h>
  54#else
  55#include <asm/MC68328.h>
  56#endif /* CONFIG_M68VZ328 */
  57#endif /* CONFIG_M68EZ328 */
  58
  59/* Turn off usage of real serial interrupt code, to "support" Copilot */
  60#ifdef CONFIG_XCOPILOT_BUGS
  61#undef USE_INTS
  62#else
  63#define USE_INTS
  64#endif
  65
  66/*
  67 * I believe this is the optimal setting that reduces the number of interrupts.
  68 * At high speeds the output might become a little "bursted" (use USTCNT_TXHE
  69 * if that bothers you), but in most cases it will not, since we try to
  70 * transmit characters every time rs_interrupt is called. Thus, quite often
  71 * you'll see that a receive interrupt occures before the transmit one.
  72 *                                  -- Vladimir Gurevich
  73 */
  74#define USTCNT_TX_INTR_MASK (USTCNT_TXEE)
  75
  76/*
  77 * 68328 and 68EZ328 UARTS are a little bit different. EZ328 has special
  78 * "Old data interrupt" which occures whenever the data stay in the FIFO
  79 * longer than 30 bits time. This allows us to use FIFO without compromising
  80 * latency. '328 does not have this feature and without the real  328-based
  81 * board I would assume that RXRE is the safest setting.
  82 *
  83 * For EZ328 I use RXHE (Half empty) interrupt to reduce the number of
  84 * interrupts. RXFE (receive queue full) causes the system to lose data
  85 * at least at 115200 baud
  86 *
  87 * If your board is busy doing other stuff, you might consider to use
  88 * RXRE (data ready intrrupt) instead.
  89 *
  90 * The other option is to make these INTR masks run-time configurable, so
  91 * that people can dynamically adapt them according to the current usage.
  92 *                                  -- Vladimir Gurevich
  93 */
  94
  95/* (es) */
  96#if defined(CONFIG_M68EZ328) || defined(CONFIG_M68VZ328)
  97#define USTCNT_RX_INTR_MASK (USTCNT_RXHE | USTCNT_ODEN)
  98#elif defined(CONFIG_M68328)
  99#define USTCNT_RX_INTR_MASK (USTCNT_RXRE)
 100#else
 101#error Please, define the Rx interrupt events for your CPU
 102#endif
 103/* (/es) */
 104
 105/*
 106 * This is our internal structure for each serial port's state.
 107 */
 108struct m68k_serial {
 109	struct tty_port		tport;
 110	char			is_cons;	/* Is this our console. */
 111	int			magic;
 112	int			baud_base;
 113	int			port;
 114	int			irq;
 115	int			type;		/* UART type */
 116	int			custom_divisor;
 117	int			x_char;		/* xon/xoff character */
 118	int			line;
 119	unsigned char		*xmit_buf;
 120	int			xmit_head;
 121	int			xmit_tail;
 122	int			xmit_cnt;
 123};
 124
 125#define SERIAL_MAGIC 0x5301
 126
 127/*
 128 * Define the number of ports supported and their irqs.
 129 */
 130#define NR_PORTS 1
 131
 132static struct m68k_serial m68k_soft[NR_PORTS];
 133
 134static unsigned int uart_irqs[NR_PORTS] = { UART_IRQ_NUM };
 135
 136/* multiple ports are contiguous in memory */
 137m68328_uart *uart_addr = (m68328_uart *)USTCNT_ADDR;
 138
 139struct tty_driver *serial_driver;
 140
 141static void change_speed(struct m68k_serial *info, struct tty_struct *tty);
 142
 143/*
 144 *	Setup for console. Argument comes from the boot command line.
 145 */
 146
 147/* note: this is messy, but it works, again, perhaps defined somewhere else?*/
 148#ifdef CONFIG_M68VZ328
 149#define CONSOLE_BAUD_RATE	19200
 150#define DEFAULT_CBAUD		B19200
 151#endif
 152
 153
 154#ifndef CONSOLE_BAUD_RATE
 155#define	CONSOLE_BAUD_RATE	9600
 156#define	DEFAULT_CBAUD		B9600
 157#endif
 158
 159
 160static int m68328_console_initted = 0;
 161static int m68328_console_baud    = CONSOLE_BAUD_RATE;
 162static int m68328_console_cbaud   = DEFAULT_CBAUD;
 163
 164
 165static inline int serial_paranoia_check(struct m68k_serial *info,
 166					char *name, const char *routine)
 167{
 168#ifdef SERIAL_PARANOIA_CHECK
 169	static const char *badmagic =
 170		"Warning: bad magic number for serial struct %s in %s\n";
 171	static const char *badinfo =
 172		"Warning: null m68k_serial for %s in %s\n";
 173
 174	if (!info) {
 175		printk(badinfo, name, routine);
 176		return 1;
 177	}
 178	if (info->magic != SERIAL_MAGIC) {
 179		printk(badmagic, name, routine);
 180		return 1;
 181	}
 182#endif
 183	return 0;
 184}
 185
 186/*
 187 * This is used to figure out the divisor speeds and the timeouts
 188 */
 189static int baud_table[] = {
 190	0, 50, 75, 110, 134, 150, 200, 300, 600, 1200, 1800, 2400, 4800,
 191	9600, 19200, 38400, 57600, 115200, 0 };
 192
 193/* Utility routines */
 194static inline int get_baud(struct m68k_serial *ss)
 195{
 196	unsigned long result = 115200;
 197	unsigned short int baud = uart_addr[ss->line].ubaud;
 198	if (GET_FIELD(baud, UBAUD_PRESCALER) == 0x38) result = 38400;
 199	result >>= GET_FIELD(baud, UBAUD_DIVIDE);
 200
 201	return result;
 202}
 203
 204/*
 205 * ------------------------------------------------------------
 206 * rs_stop() and rs_start()
 207 *
 208 * This routines are called before setting or resetting tty->stopped.
 209 * They enable or disable transmitter interrupts, as necessary.
 210 * ------------------------------------------------------------
 211 */
 212static void rs_stop(struct tty_struct *tty)
 213{
 214	struct m68k_serial *info = (struct m68k_serial *)tty->driver_data;
 215	m68328_uart *uart = &uart_addr[info->line];
 216	unsigned long flags;
 217
 218	if (serial_paranoia_check(info, tty->name, "rs_stop"))
 219		return;
 220	
 221	local_irq_save(flags);
 222	uart->ustcnt &= ~USTCNT_TXEN;
 223	local_irq_restore(flags);
 224}
 225
 226static int rs_put_char(char ch)
 227{
 228	unsigned long flags;
 229	int loops = 0;
 230
 231        local_irq_save(flags);
 232
 233	while (!(UTX & UTX_TX_AVAIL) && (loops < 1000)) {
 234        	loops++;
 235        	udelay(5);
 236        }
 237
 238	UTX_TXDATA = ch;
 239        udelay(5);
 240        local_irq_restore(flags);
 241        return 1;
 242}
 243
 244static void rs_start(struct tty_struct *tty)
 245{
 246	struct m68k_serial *info = (struct m68k_serial *)tty->driver_data;
 247	m68328_uart *uart = &uart_addr[info->line];
 248	unsigned long flags;
 249	
 250	if (serial_paranoia_check(info, tty->name, "rs_start"))
 251		return;
 252	
 253	local_irq_save(flags);
 254	if (info->xmit_cnt && info->xmit_buf && !(uart->ustcnt & USTCNT_TXEN)) {
 255#ifdef USE_INTS
 256		uart->ustcnt |= USTCNT_TXEN | USTCNT_TX_INTR_MASK;
 257#else
 258		uart->ustcnt |= USTCNT_TXEN;
 259#endif
 260	}
 261	local_irq_restore(flags);
 262}
 263
 264static void receive_chars(struct m68k_serial *info, unsigned short rx)
 265{
 266	m68328_uart *uart = &uart_addr[info->line];
 267	unsigned char ch, flag;
 268
 269	/*
 270	 * This do { } while() loop will get ALL chars out of Rx FIFO 
 271         */
 272#ifndef CONFIG_XCOPILOT_BUGS
 273	do {
 274#endif	
 275		ch = GET_FIELD(rx, URX_RXDATA);
 276	
 277		if(info->is_cons) {
 278			if(URX_BREAK & rx) { /* whee, break received */
 279				return;
 280#ifdef CONFIG_MAGIC_SYSRQ
 281			} else if (ch == 0x10) { /* ^P */
 282				show_state();
 283				show_free_areas(0);
 284				show_buffers();
 285/*				show_net_buffers(); */
 286				return;
 287			} else if (ch == 0x12) { /* ^R */
 288				emergency_restart();
 289				return;
 290#endif /* CONFIG_MAGIC_SYSRQ */
 291			}
 292		}
 293
 294		flag = TTY_NORMAL;
 295
 296		if (rx & URX_PARITY_ERROR)
 297			flag = TTY_PARITY;
 298		else if (rx & URX_OVRUN)
 299			flag = TTY_OVERRUN;
 300		else if (rx & URX_FRAME_ERROR)
 301			flag = TTY_FRAME;
 302
 303		tty_insert_flip_char(&info->tport, ch, flag);
 304#ifndef CONFIG_XCOPILOT_BUGS
 305	} while((rx = uart->urx.w) & URX_DATA_READY);
 306#endif
 307
 308	tty_schedule_flip(&info->tport);
 309}
 310
 311static void transmit_chars(struct m68k_serial *info, struct tty_struct *tty)
 312{
 313	m68328_uart *uart = &uart_addr[info->line];
 314
 315	if (info->x_char) {
 316		/* Send next char */
 317		uart->utx.b.txdata = info->x_char;
 318		info->x_char = 0;
 319		goto clear_and_return;
 320	}
 321
 322	if ((info->xmit_cnt <= 0) || !tty || tty->stopped) {
 323		/* That's peculiar... TX ints off */
 324		uart->ustcnt &= ~USTCNT_TX_INTR_MASK;
 325		goto clear_and_return;
 326	}
 327
 328	/* Send char */
 329	uart->utx.b.txdata = info->xmit_buf[info->xmit_tail++];
 330	info->xmit_tail = info->xmit_tail & (SERIAL_XMIT_SIZE-1);
 331	info->xmit_cnt--;
 332
 333	if(info->xmit_cnt <= 0) {
 334		/* All done for now... TX ints off */
 335		uart->ustcnt &= ~USTCNT_TX_INTR_MASK;
 336		goto clear_and_return;
 337	}
 338
 339clear_and_return:
 340	/* Clear interrupt (should be auto)*/
 341	return;
 342}
 343
 344/*
 345 * This is the serial driver's generic interrupt routine
 346 */
 347irqreturn_t rs_interrupt(int irq, void *dev_id)
 348{
 349	struct m68k_serial *info = dev_id;
 350	struct tty_struct *tty = tty_port_tty_get(&info->tport);
 351	m68328_uart *uart;
 352	unsigned short rx;
 353	unsigned short tx;
 354
 355	uart = &uart_addr[info->line];
 356	rx = uart->urx.w;
 357
 358#ifdef USE_INTS
 359	tx = uart->utx.w;
 360
 361	if (rx & URX_DATA_READY)
 362		receive_chars(info, rx);
 363	if (tx & UTX_TX_AVAIL)
 364		transmit_chars(info, tty);
 365#else
 366	receive_chars(info, rx);
 367#endif
 368	tty_kref_put(tty);
 369
 370	return IRQ_HANDLED;
 371}
 372
 373static int startup(struct m68k_serial *info, struct tty_struct *tty)
 374{
 375	m68328_uart *uart = &uart_addr[info->line];
 376	unsigned long flags;
 377	
 378	if (info->tport.flags & ASYNC_INITIALIZED)
 379		return 0;
 380
 381	if (!info->xmit_buf) {
 382		info->xmit_buf = (unsigned char *) __get_free_page(GFP_KERNEL);
 383		if (!info->xmit_buf)
 384			return -ENOMEM;
 385	}
 386
 387	local_irq_save(flags);
 388
 389	/*
 390	 * Clear the FIFO buffers and disable them
 391	 * (they will be reenabled in change_speed())
 392	 */
 393
 394	uart->ustcnt = USTCNT_UEN;
 395	uart->ustcnt = USTCNT_UEN | USTCNT_RXEN | USTCNT_TXEN;
 396	(void)uart->urx.w;
 397
 398	/*
 399	 * Finally, enable sequencing and interrupts
 400	 */
 401#ifdef USE_INTS
 402	uart->ustcnt = USTCNT_UEN | USTCNT_RXEN | 
 403                 USTCNT_RX_INTR_MASK | USTCNT_TX_INTR_MASK;
 404#else
 405	uart->ustcnt = USTCNT_UEN | USTCNT_RXEN | USTCNT_RX_INTR_MASK;
 406#endif
 407
 408	if (tty)
 409		clear_bit(TTY_IO_ERROR, &tty->flags);
 410	info->xmit_cnt = info->xmit_head = info->xmit_tail = 0;
 411
 412	/*
 413	 * and set the speed of the serial port
 414	 */
 415
 416	change_speed(info, tty);
 417
 418	info->tport.flags |= ASYNC_INITIALIZED;
 419	local_irq_restore(flags);
 420	return 0;
 421}
 422
 423/*
 424 * This routine will shutdown a serial port; interrupts are disabled, and
 425 * DTR is dropped if the hangup on close termio flag is on.
 426 */
 427static void shutdown(struct m68k_serial *info, struct tty_struct *tty)
 428{
 429	m68328_uart *uart = &uart_addr[info->line];
 430	unsigned long	flags;
 431
 432	uart->ustcnt = 0; /* All off! */
 433	if (!(info->tport.flags & ASYNC_INITIALIZED))
 434		return;
 435
 436	local_irq_save(flags);
 437	
 438	if (info->xmit_buf) {
 439		free_page((unsigned long) info->xmit_buf);
 440		info->xmit_buf = 0;
 441	}
 442
 443	if (tty)
 444		set_bit(TTY_IO_ERROR, &tty->flags);
 445	
 446	info->tport.flags &= ~ASYNC_INITIALIZED;
 447	local_irq_restore(flags);
 448}
 449
 450struct {
 451	int divisor, prescale;
 452}
 453#ifndef CONFIG_M68VZ328
 454 hw_baud_table[18] = {
 455	{0,0}, /* 0 */
 456	{0,0}, /* 50 */
 457	{0,0}, /* 75 */
 458	{0,0}, /* 110 */
 459	{0,0}, /* 134 */
 460	{0,0}, /* 150 */
 461	{0,0}, /* 200 */
 462	{7,0x26}, /* 300 */
 463	{6,0x26}, /* 600 */
 464	{5,0x26}, /* 1200 */
 465	{0,0}, /* 1800 */
 466	{4,0x26}, /* 2400 */
 467	{3,0x26}, /* 4800 */
 468	{2,0x26}, /* 9600 */
 469	{1,0x26}, /* 19200 */
 470	{0,0x26}, /* 38400 */
 471	{1,0x38}, /* 57600 */
 472	{0,0x38}, /* 115200 */
 473};
 474#else
 475 hw_baud_table[18] = {
 476                 {0,0}, /* 0 */
 477                 {0,0}, /* 50 */
 478                 {0,0}, /* 75 */
 479                 {0,0}, /* 110 */
 480                 {0,0}, /* 134 */
 481                 {0,0}, /* 150 */
 482                 {0,0}, /* 200 */
 483                 {0,0}, /* 300 */
 484                 {7,0x26}, /* 600 */
 485                 {6,0x26}, /* 1200 */
 486                 {0,0}, /* 1800 */
 487                 {5,0x26}, /* 2400 */
 488                 {4,0x26}, /* 4800 */
 489                 {3,0x26}, /* 9600 */
 490                 {2,0x26}, /* 19200 */
 491                 {1,0x26}, /* 38400 */
 492                 {0,0x26}, /* 57600 */
 493                 {1,0x38}, /* 115200 */
 494}; 
 495#endif
 496/* rate = 1036800 / ((65 - prescale) * (1<<divider)) */
 497
 498/*
 499 * This routine is called to set the UART divisor registers to match
 500 * the specified baud rate for a serial port.
 501 */
 502static void change_speed(struct m68k_serial *info, struct tty_struct *tty)
 503{
 504	m68328_uart *uart = &uart_addr[info->line];
 505	unsigned short port;
 506	unsigned short ustcnt;
 507	unsigned cflag;
 508	int	i;
 509
 510	cflag = tty->termios.c_cflag;
 511	if (!(port = info->port))
 512		return;
 513
 514	ustcnt = uart->ustcnt;
 515	uart->ustcnt = ustcnt & ~USTCNT_TXEN;
 516
 517	i = cflag & CBAUD;
 518        if (i & CBAUDEX) {
 519                i = (i & ~CBAUDEX) + B38400;
 520        }
 521
 522	uart->ubaud = PUT_FIELD(UBAUD_DIVIDE,    hw_baud_table[i].divisor) | 
 523		PUT_FIELD(UBAUD_PRESCALER, hw_baud_table[i].prescale);
 524
 525	ustcnt &= ~(USTCNT_PARITYEN | USTCNT_ODD_EVEN | USTCNT_STOP | USTCNT_8_7);
 526	
 527	if ((cflag & CSIZE) == CS8)
 528		ustcnt |= USTCNT_8_7;
 529		
 530	if (cflag & CSTOPB)
 531		ustcnt |= USTCNT_STOP;
 532
 533	if (cflag & PARENB)
 534		ustcnt |= USTCNT_PARITYEN;
 535	if (cflag & PARODD)
 536		ustcnt |= USTCNT_ODD_EVEN;
 537	
 538#ifdef CONFIG_SERIAL_68328_RTS_CTS
 539	if (cflag & CRTSCTS) {
 540		uart->utx.w &= ~ UTX_NOCTS;
 541	} else {
 542		uart->utx.w |= UTX_NOCTS;
 543	}
 544#endif
 545
 546	ustcnt |= USTCNT_TXEN;
 547	
 548	uart->ustcnt = ustcnt;
 549	return;
 550}
 551
 552/*
 553 * Fair output driver allows a process to speak.
 554 */
 555static void rs_fair_output(void)
 556{
 557	int left;		/* Output no more than that */
 558	unsigned long flags;
 559	struct m68k_serial *info = &m68k_soft[0];
 560	char c;
 561
 562	if (info == 0) return;
 563	if (info->xmit_buf == 0) return;
 564
 565	local_irq_save(flags);
 566	left = info->xmit_cnt;
 567	while (left != 0) {
 568		c = info->xmit_buf[info->xmit_tail];
 569		info->xmit_tail = (info->xmit_tail+1) & (SERIAL_XMIT_SIZE-1);
 570		info->xmit_cnt--;
 571		local_irq_restore(flags);
 572
 573		rs_put_char(c);
 574
 575		local_irq_save(flags);
 576		left = min(info->xmit_cnt, left-1);
 577	}
 578
 579	/* Last character is being transmitted now (hopefully). */
 580	udelay(5);
 581
 582	local_irq_restore(flags);
 583	return;
 584}
 585
 586/*
 587 * m68k_console_print is registered for printk.
 588 */
 589void console_print_68328(const char *p)
 590{
 591	char c;
 592	
 593	while((c=*(p++)) != 0) {
 594		if(c == '\n')
 595			rs_put_char('\r');
 596		rs_put_char(c);
 597	}
 598
 599	/* Comment this if you want to have a strict interrupt-driven output */
 600	rs_fair_output();
 601
 602	return;
 603}
 604
 605static void rs_set_ldisc(struct tty_struct *tty)
 606{
 607	struct m68k_serial *info = (struct m68k_serial *)tty->driver_data;
 608
 609	if (serial_paranoia_check(info, tty->name, "rs_set_ldisc"))
 610		return;
 611
 612	info->is_cons = (tty->termios.c_line == N_TTY);
 613	
 614	printk("ttyS%d console mode %s\n", info->line, info->is_cons ? "on" : "off");
 615}
 616
 617static void rs_flush_chars(struct tty_struct *tty)
 618{
 619	struct m68k_serial *info = (struct m68k_serial *)tty->driver_data;
 620	m68328_uart *uart = &uart_addr[info->line];
 621	unsigned long flags;
 622
 623	if (serial_paranoia_check(info, tty->name, "rs_flush_chars"))
 624		return;
 625#ifndef USE_INTS
 626	for(;;) {
 627#endif
 628
 629	/* Enable transmitter */
 630	local_irq_save(flags);
 631
 632	if (info->xmit_cnt <= 0 || tty->stopped || !info->xmit_buf) {
 633		local_irq_restore(flags);
 634		return;
 635	}
 636
 637#ifdef USE_INTS
 638	uart->ustcnt |= USTCNT_TXEN | USTCNT_TX_INTR_MASK;
 639#else
 640	uart->ustcnt |= USTCNT_TXEN;
 641#endif
 642
 643#ifdef USE_INTS
 644	if (uart->utx.w & UTX_TX_AVAIL) {
 645#else
 646	if (1) {
 647#endif
 648		/* Send char */
 649		uart->utx.b.txdata = info->xmit_buf[info->xmit_tail++];
 650		info->xmit_tail = info->xmit_tail & (SERIAL_XMIT_SIZE-1);
 651		info->xmit_cnt--;
 652	}
 653
 654#ifndef USE_INTS
 655	while (!(uart->utx.w & UTX_TX_AVAIL)) udelay(5);
 656	}
 657#endif
 658	local_irq_restore(flags);
 659}
 660
 661extern void console_printn(const char * b, int count);
 662
 663static int rs_write(struct tty_struct * tty,
 664		    const unsigned char *buf, int count)
 665{
 666	int	c, total = 0;
 667	struct m68k_serial *info = (struct m68k_serial *)tty->driver_data;
 668	m68328_uart *uart = &uart_addr[info->line];
 669	unsigned long flags;
 670
 671	if (serial_paranoia_check(info, tty->name, "rs_write"))
 672		return 0;
 673
 674	if (!tty || !info->xmit_buf)
 675		return 0;
 676
 677	local_save_flags(flags);
 678	while (1) {
 679		local_irq_disable();		
 680		c = min_t(int, count, min(SERIAL_XMIT_SIZE - info->xmit_cnt - 1,
 681				   SERIAL_XMIT_SIZE - info->xmit_head));
 682		local_irq_restore(flags);
 683
 684		if (c <= 0)
 685			break;
 686
 687		memcpy(info->xmit_buf + info->xmit_head, buf, c);
 688
 689		local_irq_disable();
 690		info->xmit_head = (info->xmit_head + c) & (SERIAL_XMIT_SIZE-1);
 691		info->xmit_cnt += c;
 692		local_irq_restore(flags);
 693		buf += c;
 694		count -= c;
 695		total += c;
 696	}
 697
 698	if (info->xmit_cnt && !tty->stopped) {
 699		/* Enable transmitter */
 700		local_irq_disable();		
 701#ifndef USE_INTS
 702		while(info->xmit_cnt) {
 703#endif
 704
 705		uart->ustcnt |= USTCNT_TXEN;
 706#ifdef USE_INTS
 707		uart->ustcnt |= USTCNT_TX_INTR_MASK;
 708#else
 709		while (!(uart->utx.w & UTX_TX_AVAIL)) udelay(5);
 710#endif
 711		if (uart->utx.w & UTX_TX_AVAIL) {
 712			uart->utx.b.txdata = info->xmit_buf[info->xmit_tail++];
 713			info->xmit_tail = info->xmit_tail & (SERIAL_XMIT_SIZE-1);
 714			info->xmit_cnt--;
 715		}
 716
 717#ifndef USE_INTS
 718		}
 719#endif
 720		local_irq_restore(flags);
 721	}
 722
 723	return total;
 724}
 725
 726static int rs_write_room(struct tty_struct *tty)
 727{
 728	struct m68k_serial *info = (struct m68k_serial *)tty->driver_data;
 729	int	ret;
 730				
 731	if (serial_paranoia_check(info, tty->name, "rs_write_room"))
 732		return 0;
 733	ret = SERIAL_XMIT_SIZE - info->xmit_cnt - 1;
 734	if (ret < 0)
 735		ret = 0;
 736	return ret;
 737}
 738
 739static int rs_chars_in_buffer(struct tty_struct *tty)
 740{
 741	struct m68k_serial *info = (struct m68k_serial *)tty->driver_data;
 742				
 743	if (serial_paranoia_check(info, tty->name, "rs_chars_in_buffer"))
 744		return 0;
 745	return info->xmit_cnt;
 746}
 747
 748static void rs_flush_buffer(struct tty_struct *tty)
 749{
 750	struct m68k_serial *info = (struct m68k_serial *)tty->driver_data;
 751	unsigned long flags;
 752				
 753	if (serial_paranoia_check(info, tty->name, "rs_flush_buffer"))
 754		return;
 755	local_irq_save(flags);
 756	info->xmit_cnt = info->xmit_head = info->xmit_tail = 0;
 757	local_irq_restore(flags);
 758	tty_wakeup(tty);
 759}
 760
 761/*
 762 * ------------------------------------------------------------
 763 * rs_throttle()
 764 * 
 765 * This routine is called by the upper-layer tty layer to signal that
 766 * incoming characters should be throttled.
 767 * ------------------------------------------------------------
 768 */
 769static void rs_throttle(struct tty_struct * tty)
 770{
 771	struct m68k_serial *info = (struct m68k_serial *)tty->driver_data;
 772
 773	if (serial_paranoia_check(info, tty->name, "rs_throttle"))
 774		return;
 775	
 776	if (I_IXOFF(tty))
 777		info->x_char = STOP_CHAR(tty);
 778
 779	/* Turn off RTS line (do this atomic) */
 780}
 781
 782static void rs_unthrottle(struct tty_struct * tty)
 783{
 784	struct m68k_serial *info = (struct m68k_serial *)tty->driver_data;
 785
 786	if (serial_paranoia_check(info, tty->name, "rs_unthrottle"))
 787		return;
 788	
 789	if (I_IXOFF(tty)) {
 790		if (info->x_char)
 791			info->x_char = 0;
 792		else
 793			info->x_char = START_CHAR(tty);
 794	}
 795
 796	/* Assert RTS line (do this atomic) */
 797}
 798
 799/*
 800 * ------------------------------------------------------------
 801 * rs_ioctl() and friends
 802 * ------------------------------------------------------------
 803 */
 804
 805static int get_serial_info(struct m68k_serial * info,
 806			   struct serial_struct * retinfo)
 807{
 808	struct serial_struct tmp;
 809  
 810	if (!retinfo)
 811		return -EFAULT;
 812	memset(&tmp, 0, sizeof(tmp));
 813	tmp.type = info->type;
 814	tmp.line = info->line;
 815	tmp.port = info->port;
 816	tmp.irq = info->irq;
 817	tmp.flags = info->tport.flags;
 818	tmp.baud_base = info->baud_base;
 819	tmp.close_delay = info->tport.close_delay;
 820	tmp.closing_wait = info->tport.closing_wait;
 821	tmp.custom_divisor = info->custom_divisor;
 822	if (copy_to_user(retinfo, &tmp, sizeof(*retinfo)))
 823		return -EFAULT;
 824
 825	return 0;
 826}
 827
 828static int set_serial_info(struct m68k_serial *info, struct tty_struct *tty,
 829			   struct serial_struct * new_info)
 830{
 831	struct tty_port *port = &info->tport;
 832	struct serial_struct new_serial;
 833	struct m68k_serial old_info;
 834	int 			retval = 0;
 835
 836	if (!new_info)
 837		return -EFAULT;
 838	if (copy_from_user(&new_serial, new_info, sizeof(new_serial)))
 839		return -EFAULT;
 840	old_info = *info;
 841
 842	if (!capable(CAP_SYS_ADMIN)) {
 843		if ((new_serial.baud_base != info->baud_base) ||
 844		    (new_serial.type != info->type) ||
 845		    (new_serial.close_delay != port->close_delay) ||
 846		    ((new_serial.flags & ~ASYNC_USR_MASK) !=
 847		     (port->flags & ~ASYNC_USR_MASK)))
 848			return -EPERM;
 849		port->flags = ((port->flags & ~ASYNC_USR_MASK) |
 850			       (new_serial.flags & ASYNC_USR_MASK));
 851		info->custom_divisor = new_serial.custom_divisor;
 852		goto check_and_exit;
 853	}
 854
 855	if (port->count > 1)
 856		return -EBUSY;
 857
 858	/*
 859	 * OK, past this point, all the error checking has been done.
 860	 * At this point, we start making changes.....
 861	 */
 862
 863	info->baud_base = new_serial.baud_base;
 864	port->flags = ((port->flags & ~ASYNC_FLAGS) |
 865			(new_serial.flags & ASYNC_FLAGS));
 866	info->type = new_serial.type;
 867	port->close_delay = new_serial.close_delay;
 868	port->closing_wait = new_serial.closing_wait;
 869
 870check_and_exit:
 871	retval = startup(info, tty);
 872	return retval;
 873}
 874
 875/*
 876 * get_lsr_info - get line status register info
 877 *
 878 * Purpose: Let user call ioctl() to get info when the UART physically
 879 * 	    is emptied.  On bus types like RS485, the transmitter must
 880 * 	    release the bus after transmitting. This must be done when
 881 * 	    the transmit shift register is empty, not be done when the
 882 * 	    transmit holding register is empty.  This functionality
 883 * 	    allows an RS485 driver to be written in user space. 
 884 */
 885static int get_lsr_info(struct m68k_serial * info, unsigned int *value)
 886{
 887#ifdef CONFIG_SERIAL_68328_RTS_CTS
 888	m68328_uart *uart = &uart_addr[info->line];
 889#endif
 890	unsigned char status;
 891	unsigned long flags;
 892
 893	local_irq_save(flags);
 894#ifdef CONFIG_SERIAL_68328_RTS_CTS
 895	status = (uart->utx.w & UTX_CTS_STAT) ? 1 : 0;
 896#else
 897	status = 0;
 898#endif
 899	local_irq_restore(flags);
 900	return put_user(status, value);
 901}
 902
 903/*
 904 * This routine sends a break character out the serial port.
 905 */
 906static void send_break(struct m68k_serial * info, unsigned int duration)
 907{
 908	m68328_uart *uart = &uart_addr[info->line];
 909        unsigned long flags;
 910        if (!info->port)
 911                return;
 912        local_irq_save(flags);
 913#ifdef USE_INTS	
 914	uart->utx.w |= UTX_SEND_BREAK;
 915	msleep_interruptible(duration);
 916	uart->utx.w &= ~UTX_SEND_BREAK;
 917#endif		
 918        local_irq_restore(flags);
 919}
 920
 921static int rs_ioctl(struct tty_struct *tty,
 922		    unsigned int cmd, unsigned long arg)
 923{
 924	struct m68k_serial * info = (struct m68k_serial *)tty->driver_data;
 925	int retval;
 926
 927	if (serial_paranoia_check(info, tty->name, "rs_ioctl"))
 928		return -ENODEV;
 929
 930	if ((cmd != TIOCGSERIAL) && (cmd != TIOCSSERIAL) &&
 931	    (cmd != TIOCSERCONFIG) && (cmd != TIOCSERGWILD)  &&
 932	    (cmd != TIOCSERSWILD) && (cmd != TIOCSERGSTRUCT)) {
 933		if (tty->flags & (1 << TTY_IO_ERROR))
 934		    return -EIO;
 935	}
 936	
 937	switch (cmd) {
 938		case TCSBRK:	/* SVID version: non-zero arg --> no break */
 939			retval = tty_check_change(tty);
 940			if (retval)
 941				return retval;
 942			tty_wait_until_sent(tty, 0);
 943			if (!arg)
 944				send_break(info, 250);	/* 1/4 second */
 945			return 0;
 946		case TCSBRKP:	/* support for POSIX tcsendbreak() */
 947			retval = tty_check_change(tty);
 948			if (retval)
 949				return retval;
 950			tty_wait_until_sent(tty, 0);
 951			send_break(info, arg ? arg*(100) : 250);
 952			return 0;
 953		case TIOCGSERIAL:
 954			return get_serial_info(info,
 955				       (struct serial_struct *) arg);
 956		case TIOCSSERIAL:
 957			return set_serial_info(info, tty,
 958					       (struct serial_struct *) arg);
 959		case TIOCSERGETLSR: /* Get line status register */
 960			return get_lsr_info(info, (unsigned int *) arg);
 961		case TIOCSERGSTRUCT:
 962			if (copy_to_user((struct m68k_serial *) arg,
 963				    info, sizeof(struct m68k_serial)))
 964				return -EFAULT;
 965			return 0;
 966		default:
 967			return -ENOIOCTLCMD;
 968		}
 969	return 0;
 970}
 971
 972static void rs_set_termios(struct tty_struct *tty, struct ktermios *old_termios)
 973{
 974	struct m68k_serial *info = (struct m68k_serial *)tty->driver_data;
 975
 976	change_speed(info, tty);
 977
 978	if ((old_termios->c_cflag & CRTSCTS) &&
 979	    !(tty->termios.c_cflag & CRTSCTS))
 980		rs_start(tty);
 981	
 982}
 983
 984/*
 985 * ------------------------------------------------------------
 986 * rs_close()
 987 * 
 988 * This routine is called when the serial port gets closed.  First, we
 989 * wait for the last remaining data to be sent.  Then, we unlink its
 990 * S structure from the interrupt chain if necessary, and we free
 991 * that IRQ if nothing is left in the chain.
 992 * ------------------------------------------------------------
 993 */
 994static void rs_close(struct tty_struct *tty, struct file * filp)
 995{
 996	struct m68k_serial * info = (struct m68k_serial *)tty->driver_data;
 997	struct tty_port *port = &info->tport;
 998	m68328_uart *uart = &uart_addr[info->line];
 999	unsigned long flags;
1000
1001	if (serial_paranoia_check(info, tty->name, "rs_close"))
1002		return;
1003	
1004	local_irq_save(flags);
1005	
1006	if (tty_hung_up_p(filp)) {
1007		local_irq_restore(flags);
1008		return;
1009	}
1010	
1011	if ((tty->count == 1) && (port->count != 1)) {
1012		/*
1013		 * Uh, oh.  tty->count is 1, which means that the tty
1014		 * structure will be freed.  Info->count should always
1015		 * be one in these conditions.  If it's greater than
1016		 * one, we've got real problems, since it means the
1017		 * serial port won't be shutdown.
1018		 */
1019		printk("rs_close: bad serial port count; tty->count is 1, "
1020		       "port->count is %d\n", port->count);
1021		port->count = 1;
1022	}
1023	if (--port->count < 0) {
1024		printk("rs_close: bad serial port count for ttyS%d: %d\n",
1025		       info->line, port->count);
1026		port->count = 0;
1027	}
1028	if (port->count) {
1029		local_irq_restore(flags);
1030		return;
1031	}
1032	port->flags |= ASYNC_CLOSING;
1033	/*
1034	 * Now we wait for the transmit buffer to clear; and we notify 
1035	 * the line discipline to only process XON/XOFF characters.
1036	 */
1037	tty->closing = 1;
1038	if (port->closing_wait != ASYNC_CLOSING_WAIT_NONE)
1039		tty_wait_until_sent(tty, port->closing_wait);
1040	/*
1041	 * At this point we stop accepting input.  To do this, we
1042	 * disable the receive line status interrupts, and tell the
1043	 * interrupt driver to stop checking the data ready bit in the
1044	 * line status register.
1045	 */
1046
1047	uart->ustcnt &= ~USTCNT_RXEN;
1048	uart->ustcnt &= ~(USTCNT_RXEN | USTCNT_RX_INTR_MASK);
1049
1050	shutdown(info, tty);
1051	rs_flush_buffer(tty);
1052		
1053	tty_ldisc_flush(tty);
1054	tty->closing = 0;
1055	tty_port_tty_set(&info->tport, NULL);
1056#warning "This is not and has never been valid so fix it"	
1057#if 0
1058	if (tty->ldisc.num != ldiscs[N_TTY].num) {
1059		if (tty->ldisc.close)
1060			(tty->ldisc.close)(tty);
1061		tty->ldisc = ldiscs[N_TTY];
1062		tty->termios.c_line = N_TTY;
1063		if (tty->ldisc.open)
1064			(tty->ldisc.open)(tty);
1065	}
1066#endif	
1067	if (port->blocked_open) {
1068		if (port->close_delay)
1069			msleep_interruptible(jiffies_to_msecs(port->close_delay));
1070		wake_up_interruptible(&port->open_wait);
1071	}
1072	port->flags &= ~(ASYNC_NORMAL_ACTIVE|ASYNC_CLOSING);
1073	wake_up_interruptible(&port->close_wait);
1074	local_irq_restore(flags);
1075}
1076
1077/*
1078 * rs_hangup() --- called by tty_hangup() when a hangup is signaled.
1079 */
1080void rs_hangup(struct tty_struct *tty)
1081{
1082	struct m68k_serial * info = (struct m68k_serial *)tty->driver_data;
1083	
1084	if (serial_paranoia_check(info, tty->name, "rs_hangup"))
1085		return;
1086	
1087	rs_flush_buffer(tty);
1088	shutdown(info, tty);
1089	info->tport.count = 0;
1090	info->tport.flags &= ~ASYNC_NORMAL_ACTIVE;
1091	tty_port_tty_set(&info->tport, NULL);
1092	wake_up_interruptible(&info->tport.open_wait);
1093}
1094
1095/*
1096 * This routine is called whenever a serial port is opened.  It
1097 * enables interrupts for a serial port, linking in its S structure into
1098 * the IRQ chain.   It also performs the serial-specific
1099 * initialization for the tty structure.
1100 */
1101int rs_open(struct tty_struct *tty, struct file * filp)
1102{
1103	struct m68k_serial	*info;
1104	int retval;
1105
1106	info = &m68k_soft[tty->index];
1107
1108	if (serial_paranoia_check(info, tty->name, "rs_open"))
1109		return -ENODEV;
1110
1111	info->tport.count++;
1112	tty->driver_data = info;
1113	tty_port_tty_set(&info->tport, tty);
1114
1115	/*
1116	 * Start up serial port
1117	 */
1118	retval = startup(info, tty);
1119	if (retval)
1120		return retval;
1121
1122	return tty_port_block_til_ready(&info->tport, tty, filp);
1123}
1124
1125/* Finally, routines used to initialize the serial driver. */
1126
1127static void show_serial_version(void)
1128{
1129	printk("MC68328 serial driver version 1.00\n");
1130}
1131
1132static const struct tty_operations rs_ops = {
1133	.open = rs_open,
1134	.close = rs_close,
1135	.write = rs_write,
1136	.flush_chars = rs_flush_chars,
1137	.write_room = rs_write_room,
1138	.chars_in_buffer = rs_chars_in_buffer,
1139	.flush_buffer = rs_flush_buffer,
1140	.ioctl = rs_ioctl,
1141	.throttle = rs_throttle,
1142	.unthrottle = rs_unthrottle,
1143	.set_termios = rs_set_termios,
1144	.stop = rs_stop,
1145	.start = rs_start,
1146	.hangup = rs_hangup,
1147	.set_ldisc = rs_set_ldisc,
1148};
1149
1150static const struct tty_port_operations rs_port_ops = {
1151};
1152
1153/* rs_init inits the driver */
1154static int __init
1155rs68328_init(void)
1156{
1157	unsigned long flags;
1158	int i;
1159	struct m68k_serial *info;
1160
1161	serial_driver = alloc_tty_driver(NR_PORTS);
1162	if (!serial_driver)
1163		return -ENOMEM;
1164
1165	show_serial_version();
1166
1167	/* Initialize the tty_driver structure */
1168	/* SPARC: Not all of this is exactly right for us. */
1169	
1170	serial_driver->name = "ttyS";
1171	serial_driver->major = TTY_MAJOR;
1172	serial_driver->minor_start = 64;
1173	serial_driver->type = TTY_DRIVER_TYPE_SERIAL;
1174	serial_driver->subtype = SERIAL_TYPE_NORMAL;
1175	serial_driver->init_termios = tty_std_termios;
1176	serial_driver->init_termios.c_cflag = 
1177			m68328_console_cbaud | CS8 | CREAD | HUPCL | CLOCAL;
1178	serial_driver->flags = TTY_DRIVER_REAL_RAW;
1179	tty_set_operations(serial_driver, &rs_ops);
1180
1181	local_irq_save(flags);
1182
1183	for(i=0;i<NR_PORTS;i++) {
1184
1185	    info = &m68k_soft[i];
1186	    tty_port_init(&info->tport);
1187	    info->tport.ops = &rs_port_ops;
1188	    info->magic = SERIAL_MAGIC;
1189	    info->port = (int) &uart_addr[i];
1190	    info->irq = uart_irqs[i];
1191	    info->custom_divisor = 16;
1192	    info->x_char = 0;
1193	    info->line = i;
1194	    info->is_cons = 1; /* Means shortcuts work */
1195	    
1196	    printk("%s%d at 0x%08x (irq = %d)", serial_driver->name, info->line, 
1197		   info->port, info->irq);
1198	    printk(" is a builtin MC68328 UART\n");
1199	    
1200#ifdef CONFIG_M68VZ328
1201		if (i > 0 )
1202			PJSEL &= 0xCF;  /* PSW enable second port output */
1203#endif
1204
1205	    if (request_irq(uart_irqs[i],
1206			    rs_interrupt,
1207			    0,
1208			    "M68328_UART", info))
1209                panic("Unable to attach 68328 serial interrupt\n");
1210
1211	    tty_port_link_device(&info->tport, serial_driver, i);
1212	}
1213	local_irq_restore(flags);
1214
1215	if (tty_register_driver(serial_driver)) {
1216		put_tty_driver(serial_driver);
1217		for (i = 0; i < NR_PORTS; i++)
1218			tty_port_destroy(&m68k_soft[i].tport);
1219		printk(KERN_ERR "Couldn't register serial driver\n");
1220		return -ENOMEM;
1221	}
1222
1223	return 0;
1224}
1225
1226module_init(rs68328_init);
1227
1228
1229
1230static void m68328_set_baud(void)
1231{
1232	unsigned short ustcnt;
1233	int	i;
1234
1235	ustcnt = USTCNT;
1236	USTCNT = ustcnt & ~USTCNT_TXEN;
1237
1238again:
1239	for (i = 0; i < ARRAY_SIZE(baud_table); i++)
1240		if (baud_table[i] == m68328_console_baud)
1241			break;
1242	if (i >= ARRAY_SIZE(baud_table)) {
1243		m68328_console_baud = 9600;
1244		goto again;
1245	}
1246
1247	UBAUD = PUT_FIELD(UBAUD_DIVIDE,    hw_baud_table[i].divisor) | 
1248		PUT_FIELD(UBAUD_PRESCALER, hw_baud_table[i].prescale);
1249	ustcnt &= ~(USTCNT_PARITYEN | USTCNT_ODD_EVEN | USTCNT_STOP | USTCNT_8_7);
1250	ustcnt |= USTCNT_8_7;
1251	ustcnt |= USTCNT_TXEN;
1252	USTCNT = ustcnt;
1253	m68328_console_initted = 1;
1254	return;
1255}
1256
1257
1258int m68328_console_setup(struct console *cp, char *arg)
1259{
1260	int		i, n = CONSOLE_BAUD_RATE;
1261
1262	if (!cp)
1263		return(-1);
1264
1265	if (arg)
1266		n = simple_strtoul(arg,NULL,0);
1267
1268	for (i = 0; i < ARRAY_SIZE(baud_table); i++)
1269		if (baud_table[i] == n)
1270			break;
1271	if (i < ARRAY_SIZE(baud_table)) {
1272		m68328_console_baud = n;
1273		m68328_console_cbaud = 0;
1274		if (i > 15) {
1275			m68328_console_cbaud |= CBAUDEX;
1276			i -= 15;
1277		}
1278		m68328_console_cbaud |= i;
1279	}
1280
1281	m68328_set_baud(); /* make sure baud rate changes */
1282	return(0);
1283}
1284
1285
1286static struct tty_driver *m68328_console_device(struct console *c, int *index)
1287{
1288	*index = c->index;
1289	return serial_driver;
1290}
1291
1292
1293void m68328_console_write (struct console *co, const char *str,
1294			   unsigned int count)
1295{
1296	if (!m68328_console_initted)
1297		m68328_set_baud();
1298    while (count--) {
1299        if (*str == '\n')
1300           rs_put_char('\r');
1301        rs_put_char( *str++ );
1302    }
1303}
1304
1305
1306static struct console m68328_driver = {
1307	.name		= "ttyS",
1308	.write		= m68328_console_write,
1309	.device		= m68328_console_device,
1310	.setup		= m68328_console_setup,
1311	.flags		= CON_PRINTBUFFER,
1312	.index		= -1,
1313};
1314
1315
1316static int __init m68328_console_init(void)
1317{
1318	register_console(&m68328_driver);
1319	return 0;
1320}
1321
1322console_initcall(m68328_console_init);