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Note: File does not exist in v6.8.
   1/*
   2 *  m32r_sio.c
   3 *
   4 *  Driver for M32R serial ports
   5 *
   6 *  Based on drivers/char/serial.c, by Linus Torvalds, Theodore Ts'o.
   7 *  Based on drivers/serial/8250.c.
   8 *
   9 *  Copyright (C) 2001  Russell King.
  10 *  Copyright (C) 2004  Hirokazu Takata <takata at linux-m32r.org>
  11 *
  12 * This program is free software; you can redistribute it and/or modify
  13 * it under the terms of the GNU General Public License as published by
  14 * the Free Software Foundation; either version 2 of the License, or
  15 * (at your option) any later version.
  16 */
  17
  18/*
  19 * A note about mapbase / membase
  20 *
  21 *  mapbase is the physical address of the IO port.  Currently, we don't
  22 *  support this very well, and it may well be dropped from this driver
  23 *  in future.  As such, mapbase should be NULL.
  24 *
  25 *  membase is an 'ioremapped' cookie.  This is compatible with the old
  26 *  serial.c driver, and is currently the preferred form.
  27 */
  28
  29#if defined(CONFIG_SERIAL_M32R_SIO_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
  30#define SUPPORT_SYSRQ
  31#endif
  32
  33#include <linux/module.h>
  34#include <linux/tty.h>
  35#include <linux/tty_flip.h>
  36#include <linux/ioport.h>
  37#include <linux/init.h>
  38#include <linux/console.h>
  39#include <linux/sysrq.h>
  40#include <linux/serial.h>
  41#include <linux/delay.h>
  42
  43#include <asm/m32r.h>
  44#include <asm/io.h>
  45#include <asm/irq.h>
  46
  47#define BAUD_RATE	115200
  48
  49#include <linux/serial_core.h>
  50#include "m32r_sio_reg.h"
  51
  52#define PASS_LIMIT	256
  53
  54/* Standard COM flags */
  55#define STD_COM_FLAGS (UPF_BOOT_AUTOCONF | UPF_SKIP_TEST)
  56
  57static const struct {
  58	unsigned int port;
  59	unsigned int irq;
  60} old_serial_port[] = {
  61#if defined(CONFIG_PLAT_USRV)
  62	/* PORT  IRQ            FLAGS */
  63	{ 0x3F8, PLD_IRQ_UART0 }, /* ttyS0 */
  64	{ 0x2F8, PLD_IRQ_UART1 }, /* ttyS1 */
  65#elif defined(CONFIG_SERIAL_M32R_PLDSIO)
  66	{ ((unsigned long)PLD_ESIO0CR), PLD_IRQ_SIO0_RCV }, /* ttyS0 */
  67#else
  68	{ M32R_SIO_OFFSET, M32R_IRQ_SIO0_R }, /* ttyS0 */
  69#endif
  70};
  71
  72#define UART_NR	ARRAY_SIZE(old_serial_port)
  73
  74struct uart_sio_port {
  75	struct uart_port	port;
  76	struct timer_list	timer;		/* "no irq" timer */
  77	struct list_head	list;		/* ports on this IRQ */
  78	unsigned char		ier;
  79};
  80
  81struct irq_info {
  82	spinlock_t		lock;
  83	struct list_head	*head;
  84};
  85
  86static struct irq_info irq_lists[NR_IRQS];
  87
  88#ifdef CONFIG_SERIAL_M32R_PLDSIO
  89
  90#define __sio_in(x) inw((unsigned long)(x))
  91#define __sio_out(v,x) outw((v),(unsigned long)(x))
  92
  93static inline void sio_set_baud_rate(unsigned long baud)
  94{
  95	unsigned short sbaud;
  96	sbaud = (boot_cpu_data.bus_clock / (baud * 4))-1;
  97	__sio_out(sbaud, PLD_ESIO0BAUR);
  98}
  99
 100static void sio_reset(void)
 101{
 102	unsigned short tmp;
 103
 104	tmp = __sio_in(PLD_ESIO0RXB);
 105	tmp = __sio_in(PLD_ESIO0RXB);
 106	tmp = __sio_in(PLD_ESIO0CR);
 107	sio_set_baud_rate(BAUD_RATE);
 108	__sio_out(0x0300, PLD_ESIO0CR);
 109	__sio_out(0x0003, PLD_ESIO0CR);
 110}
 111
 112static void sio_init(void)
 113{
 114	unsigned short tmp;
 115
 116	tmp = __sio_in(PLD_ESIO0RXB);
 117	tmp = __sio_in(PLD_ESIO0RXB);
 118	tmp = __sio_in(PLD_ESIO0CR);
 119	__sio_out(0x0300, PLD_ESIO0CR);
 120	__sio_out(0x0003, PLD_ESIO0CR);
 121}
 122
 123static void sio_error(int *status)
 124{
 125	printk("SIO0 error[%04x]\n", *status);
 126	do {
 127		sio_init();
 128	} while ((*status = __sio_in(PLD_ESIO0CR)) != 3);
 129}
 130
 131#else /* not CONFIG_SERIAL_M32R_PLDSIO */
 132
 133#define __sio_in(x) inl(x)
 134#define __sio_out(v,x) outl((v),(x))
 135
 136static inline void sio_set_baud_rate(unsigned long baud)
 137{
 138	unsigned long i, j;
 139
 140	i = boot_cpu_data.bus_clock / (baud * 16);
 141	j = (boot_cpu_data.bus_clock - (i * baud * 16)) / baud;
 142	i -= 1;
 143	j = (j + 1) >> 1;
 144
 145	__sio_out(i, M32R_SIO0_BAUR_PORTL);
 146	__sio_out(j, M32R_SIO0_RBAUR_PORTL);
 147}
 148
 149static void sio_reset(void)
 150{
 151	__sio_out(0x00000300, M32R_SIO0_CR_PORTL);	/* init status */
 152	__sio_out(0x00000800, M32R_SIO0_MOD1_PORTL);	/* 8bit        */
 153	__sio_out(0x00000080, M32R_SIO0_MOD0_PORTL);	/* 1stop non   */
 154	sio_set_baud_rate(BAUD_RATE);
 155	__sio_out(0x00000000, M32R_SIO0_TRCR_PORTL);
 156	__sio_out(0x00000003, M32R_SIO0_CR_PORTL);	/* RXCEN */
 157}
 158
 159static void sio_init(void)
 160{
 161	unsigned int tmp;
 162
 163	tmp = __sio_in(M32R_SIO0_RXB_PORTL);
 164	tmp = __sio_in(M32R_SIO0_RXB_PORTL);
 165	tmp = __sio_in(M32R_SIO0_STS_PORTL);
 166	__sio_out(0x00000003, M32R_SIO0_CR_PORTL);
 167}
 168
 169static void sio_error(int *status)
 170{
 171	printk("SIO0 error[%04x]\n", *status);
 172	do {
 173		sio_init();
 174	} while ((*status = __sio_in(M32R_SIO0_CR_PORTL)) != 3);
 175}
 176
 177#endif /* CONFIG_SERIAL_M32R_PLDSIO */
 178
 179static unsigned int sio_in(struct uart_sio_port *up, int offset)
 180{
 181	return __sio_in(up->port.iobase + offset);
 182}
 183
 184static void sio_out(struct uart_sio_port *up, int offset, int value)
 185{
 186	__sio_out(value, up->port.iobase + offset);
 187}
 188
 189static unsigned int serial_in(struct uart_sio_port *up, int offset)
 190{
 191	if (!offset)
 192		return 0;
 193
 194	return __sio_in(offset);
 195}
 196
 197static void serial_out(struct uart_sio_port *up, int offset, int value)
 198{
 199	if (!offset)
 200		return;
 201
 202	__sio_out(value, offset);
 203}
 204
 205static void m32r_sio_stop_tx(struct uart_port *port)
 206{
 207	struct uart_sio_port *up =
 208		container_of(port, struct uart_sio_port, port);
 209
 210	if (up->ier & UART_IER_THRI) {
 211		up->ier &= ~UART_IER_THRI;
 212		serial_out(up, UART_IER, up->ier);
 213	}
 214}
 215
 216static void m32r_sio_start_tx(struct uart_port *port)
 217{
 218#ifdef CONFIG_SERIAL_M32R_PLDSIO
 219	struct uart_sio_port *up =
 220		container_of(port, struct uart_sio_port, port);
 221	struct circ_buf *xmit = &up->port.state->xmit;
 222
 223	if (!(up->ier & UART_IER_THRI)) {
 224		up->ier |= UART_IER_THRI;
 225		serial_out(up, UART_IER, up->ier);
 226		if (!uart_circ_empty(xmit)) {
 227			serial_out(up, UART_TX, xmit->buf[xmit->tail]);
 228			xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
 229			up->port.icount.tx++;
 230		}
 231	}
 232	while((serial_in(up, UART_LSR) & UART_EMPTY) != UART_EMPTY);
 233#else
 234	struct uart_sio_port *up =
 235		container_of(port, struct uart_sio_port, port);
 236
 237	if (!(up->ier & UART_IER_THRI)) {
 238		up->ier |= UART_IER_THRI;
 239		serial_out(up, UART_IER, up->ier);
 240	}
 241#endif
 242}
 243
 244static void m32r_sio_stop_rx(struct uart_port *port)
 245{
 246	struct uart_sio_port *up =
 247		container_of(port, struct uart_sio_port, port);
 248
 249	up->ier &= ~UART_IER_RLSI;
 250	up->port.read_status_mask &= ~UART_LSR_DR;
 251	serial_out(up, UART_IER, up->ier);
 252}
 253
 254static void m32r_sio_enable_ms(struct uart_port *port)
 255{
 256	struct uart_sio_port *up =
 257		container_of(port, struct uart_sio_port, port);
 258
 259	up->ier |= UART_IER_MSI;
 260	serial_out(up, UART_IER, up->ier);
 261}
 262
 263static void receive_chars(struct uart_sio_port *up, int *status)
 264{
 265	struct tty_port *port = &up->port.state->port;
 266	unsigned char ch;
 267	unsigned char flag;
 268	int max_count = 256;
 269
 270	do {
 271		ch = sio_in(up, SIORXB);
 272		flag = TTY_NORMAL;
 273		up->port.icount.rx++;
 274
 275		if (unlikely(*status & (UART_LSR_BI | UART_LSR_PE |
 276				       UART_LSR_FE | UART_LSR_OE))) {
 277			/*
 278			 * For statistics only
 279			 */
 280			if (*status & UART_LSR_BI) {
 281				*status &= ~(UART_LSR_FE | UART_LSR_PE);
 282				up->port.icount.brk++;
 283				/*
 284				 * We do the SysRQ and SAK checking
 285				 * here because otherwise the break
 286				 * may get masked by ignore_status_mask
 287				 * or read_status_mask.
 288				 */
 289				if (uart_handle_break(&up->port))
 290					goto ignore_char;
 291			} else if (*status & UART_LSR_PE)
 292				up->port.icount.parity++;
 293			else if (*status & UART_LSR_FE)
 294				up->port.icount.frame++;
 295			if (*status & UART_LSR_OE)
 296				up->port.icount.overrun++;
 297
 298			/*
 299			 * Mask off conditions which should be ingored.
 300			 */
 301			*status &= up->port.read_status_mask;
 302
 303			if (*status & UART_LSR_BI) {
 304				pr_debug("handling break....\n");
 305				flag = TTY_BREAK;
 306			} else if (*status & UART_LSR_PE)
 307				flag = TTY_PARITY;
 308			else if (*status & UART_LSR_FE)
 309				flag = TTY_FRAME;
 310		}
 311		if (uart_handle_sysrq_char(&up->port, ch))
 312			goto ignore_char;
 313		if ((*status & up->port.ignore_status_mask) == 0)
 314			tty_insert_flip_char(port, ch, flag);
 315
 316		if (*status & UART_LSR_OE) {
 317			/*
 318			 * Overrun is special, since it's reported
 319			 * immediately, and doesn't affect the current
 320			 * character.
 321			 */
 322			tty_insert_flip_char(port, 0, TTY_OVERRUN);
 323		}
 324	ignore_char:
 325		*status = serial_in(up, UART_LSR);
 326	} while ((*status & UART_LSR_DR) && (max_count-- > 0));
 327
 328	spin_unlock(&up->port.lock);
 329	tty_flip_buffer_push(port);
 330	spin_lock(&up->port.lock);
 331}
 332
 333static void transmit_chars(struct uart_sio_port *up)
 334{
 335	struct circ_buf *xmit = &up->port.state->xmit;
 336	int count;
 337
 338	if (up->port.x_char) {
 339#ifndef CONFIG_SERIAL_M32R_PLDSIO	/* XXX */
 340		serial_out(up, UART_TX, up->port.x_char);
 341#endif
 342		up->port.icount.tx++;
 343		up->port.x_char = 0;
 344		return;
 345	}
 346	if (uart_circ_empty(xmit) || uart_tx_stopped(&up->port)) {
 347		m32r_sio_stop_tx(&up->port);
 348		return;
 349	}
 350
 351	count = up->port.fifosize;
 352	do {
 353		serial_out(up, UART_TX, xmit->buf[xmit->tail]);
 354		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
 355		up->port.icount.tx++;
 356		if (uart_circ_empty(xmit))
 357			break;
 358		while (!(serial_in(up, UART_LSR) & UART_LSR_THRE));
 359
 360	} while (--count > 0);
 361
 362	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
 363		uart_write_wakeup(&up->port);
 364
 365	pr_debug("THRE...\n");
 366
 367	if (uart_circ_empty(xmit))
 368		m32r_sio_stop_tx(&up->port);
 369}
 370
 371/*
 372 * This handles the interrupt from one port.
 373 */
 374static inline void m32r_sio_handle_port(struct uart_sio_port *up,
 375	unsigned int status)
 376{
 377	pr_debug("status = %x...\n", status);
 378
 379	if (status & 0x04)
 380		receive_chars(up, &status);
 381	if (status & 0x01)
 382		transmit_chars(up);
 383}
 384
 385/*
 386 * This is the serial driver's interrupt routine.
 387 *
 388 * Arjan thinks the old way was overly complex, so it got simplified.
 389 * Alan disagrees, saying that need the complexity to handle the weird
 390 * nature of ISA shared interrupts.  (This is a special exception.)
 391 *
 392 * In order to handle ISA shared interrupts properly, we need to check
 393 * that all ports have been serviced, and therefore the ISA interrupt
 394 * line has been de-asserted.
 395 *
 396 * This means we need to loop through all ports. checking that they
 397 * don't have an interrupt pending.
 398 */
 399static irqreturn_t m32r_sio_interrupt(int irq, void *dev_id)
 400{
 401	struct irq_info *i = dev_id;
 402	struct list_head *l, *end = NULL;
 403	int pass_counter = 0;
 404
 405	pr_debug("m32r_sio_interrupt(%d)...\n", irq);
 406
 407#ifdef CONFIG_SERIAL_M32R_PLDSIO
 408//	if (irq == PLD_IRQ_SIO0_SND)
 409//		irq = PLD_IRQ_SIO0_RCV;
 410#else
 411	if (irq == M32R_IRQ_SIO0_S)
 412		irq = M32R_IRQ_SIO0_R;
 413#endif
 414
 415	spin_lock(&i->lock);
 416
 417	l = i->head;
 418	do {
 419		struct uart_sio_port *up;
 420		unsigned int sts;
 421
 422		up = list_entry(l, struct uart_sio_port, list);
 423
 424		sts = sio_in(up, SIOSTS);
 425		if (sts & 0x5) {
 426			spin_lock(&up->port.lock);
 427			m32r_sio_handle_port(up, sts);
 428			spin_unlock(&up->port.lock);
 429
 430			end = NULL;
 431		} else if (end == NULL)
 432			end = l;
 433
 434		l = l->next;
 435
 436		if (l == i->head && pass_counter++ > PASS_LIMIT) {
 437			if (sts & 0xe0)
 438				sio_error(&sts);
 439			break;
 440		}
 441	} while (l != end);
 442
 443	spin_unlock(&i->lock);
 444
 445	pr_debug("end.\n");
 446
 447	return IRQ_HANDLED;
 448}
 449
 450/*
 451 * To support ISA shared interrupts, we need to have one interrupt
 452 * handler that ensures that the IRQ line has been deasserted
 453 * before returning.  Failing to do this will result in the IRQ
 454 * line being stuck active, and, since ISA irqs are edge triggered,
 455 * no more IRQs will be seen.
 456 */
 457static void serial_do_unlink(struct irq_info *i, struct uart_sio_port *up)
 458{
 459	spin_lock_irq(&i->lock);
 460
 461	if (!list_empty(i->head)) {
 462		if (i->head == &up->list)
 463			i->head = i->head->next;
 464		list_del(&up->list);
 465	} else {
 466		BUG_ON(i->head != &up->list);
 467		i->head = NULL;
 468	}
 469
 470	spin_unlock_irq(&i->lock);
 471}
 472
 473static int serial_link_irq_chain(struct uart_sio_port *up)
 474{
 475	struct irq_info *i = irq_lists + up->port.irq;
 476	int ret, irq_flags = 0;
 477
 478	spin_lock_irq(&i->lock);
 479
 480	if (i->head) {
 481		list_add(&up->list, i->head);
 482		spin_unlock_irq(&i->lock);
 483
 484		ret = 0;
 485	} else {
 486		INIT_LIST_HEAD(&up->list);
 487		i->head = &up->list;
 488		spin_unlock_irq(&i->lock);
 489
 490		ret = request_irq(up->port.irq, m32r_sio_interrupt,
 491				  irq_flags, "SIO0-RX", i);
 492		ret |= request_irq(up->port.irq + 1, m32r_sio_interrupt,
 493				  irq_flags, "SIO0-TX", i);
 494		if (ret < 0)
 495			serial_do_unlink(i, up);
 496	}
 497
 498	return ret;
 499}
 500
 501static void serial_unlink_irq_chain(struct uart_sio_port *up)
 502{
 503	struct irq_info *i = irq_lists + up->port.irq;
 504
 505	BUG_ON(i->head == NULL);
 506
 507	if (list_empty(i->head)) {
 508		free_irq(up->port.irq, i);
 509		free_irq(up->port.irq + 1, i);
 510	}
 511
 512	serial_do_unlink(i, up);
 513}
 514
 515/*
 516 * This function is used to handle ports that do not have an interrupt.
 517 */
 518static void m32r_sio_timeout(unsigned long data)
 519{
 520	struct uart_sio_port *up = (struct uart_sio_port *)data;
 521	unsigned int timeout;
 522	unsigned int sts;
 523
 524	sts = sio_in(up, SIOSTS);
 525	if (sts & 0x5) {
 526		spin_lock(&up->port.lock);
 527		m32r_sio_handle_port(up, sts);
 528		spin_unlock(&up->port.lock);
 529	}
 530
 531	timeout = up->port.timeout;
 532	timeout = timeout > 6 ? (timeout / 2 - 2) : 1;
 533	mod_timer(&up->timer, jiffies + timeout);
 534}
 535
 536static unsigned int m32r_sio_tx_empty(struct uart_port *port)
 537{
 538	struct uart_sio_port *up =
 539		container_of(port, struct uart_sio_port, port);
 540	unsigned long flags;
 541	unsigned int ret;
 542
 543	spin_lock_irqsave(&up->port.lock, flags);
 544	ret = serial_in(up, UART_LSR) & UART_LSR_TEMT ? TIOCSER_TEMT : 0;
 545	spin_unlock_irqrestore(&up->port.lock, flags);
 546
 547	return ret;
 548}
 549
 550static unsigned int m32r_sio_get_mctrl(struct uart_port *port)
 551{
 552	return 0;
 553}
 554
 555static void m32r_sio_set_mctrl(struct uart_port *port, unsigned int mctrl)
 556{
 557
 558}
 559
 560static void m32r_sio_break_ctl(struct uart_port *port, int break_state)
 561{
 562
 563}
 564
 565static int m32r_sio_startup(struct uart_port *port)
 566{
 567	struct uart_sio_port *up =
 568		container_of(port, struct uart_sio_port, port);
 569	int retval;
 570
 571	sio_init();
 572
 573	/*
 574	 * If the "interrupt" for this port doesn't correspond with any
 575	 * hardware interrupt, we use a timer-based system.  The original
 576	 * driver used to do this with IRQ0.
 577	 */
 578	if (!up->port.irq) {
 579		unsigned int timeout = up->port.timeout;
 580
 581		timeout = timeout > 6 ? (timeout / 2 - 2) : 1;
 582
 583		up->timer.data = (unsigned long)up;
 584		mod_timer(&up->timer, jiffies + timeout);
 585	} else {
 586		retval = serial_link_irq_chain(up);
 587		if (retval)
 588			return retval;
 589	}
 590
 591	/*
 592	 * Finally, enable interrupts.  Note: Modem status interrupts
 593	 * are set via set_termios(), which will be occurring imminently
 594	 * anyway, so we don't enable them here.
 595	 * - M32R_SIO: 0x0c
 596	 * - M32R_PLDSIO: 0x04
 597	 */
 598	up->ier = UART_IER_MSI | UART_IER_RLSI | UART_IER_RDI;
 599	sio_out(up, SIOTRCR, up->ier);
 600
 601	/*
 602	 * And clear the interrupt registers again for luck.
 603	 */
 604	sio_reset();
 605
 606	return 0;
 607}
 608
 609static void m32r_sio_shutdown(struct uart_port *port)
 610{
 611	struct uart_sio_port *up =
 612		container_of(port, struct uart_sio_port, port);
 613
 614	/*
 615	 * Disable interrupts from this port
 616	 */
 617	up->ier = 0;
 618	sio_out(up, SIOTRCR, 0);
 619
 620	/*
 621	 * Disable break condition and FIFOs
 622	 */
 623
 624	sio_init();
 625
 626	if (!up->port.irq)
 627		del_timer_sync(&up->timer);
 628	else
 629		serial_unlink_irq_chain(up);
 630}
 631
 632static unsigned int m32r_sio_get_divisor(struct uart_port *port,
 633	unsigned int baud)
 634{
 635	return uart_get_divisor(port, baud);
 636}
 637
 638static void m32r_sio_set_termios(struct uart_port *port,
 639	struct ktermios *termios, struct ktermios *old)
 640{
 641	struct uart_sio_port *up =
 642		container_of(port, struct uart_sio_port, port);
 643	unsigned char cval = 0;
 644	unsigned long flags;
 645	unsigned int baud, quot;
 646
 647	switch (termios->c_cflag & CSIZE) {
 648	case CS5:
 649		cval = UART_LCR_WLEN5;
 650		break;
 651	case CS6:
 652		cval = UART_LCR_WLEN6;
 653		break;
 654	case CS7:
 655		cval = UART_LCR_WLEN7;
 656		break;
 657	default:
 658	case CS8:
 659		cval = UART_LCR_WLEN8;
 660		break;
 661	}
 662
 663	if (termios->c_cflag & CSTOPB)
 664		cval |= UART_LCR_STOP;
 665	if (termios->c_cflag & PARENB)
 666		cval |= UART_LCR_PARITY;
 667	if (!(termios->c_cflag & PARODD))
 668		cval |= UART_LCR_EPAR;
 669#ifdef CMSPAR
 670	if (termios->c_cflag & CMSPAR)
 671		cval |= UART_LCR_SPAR;
 672#endif
 673
 674	/*
 675	 * Ask the core to calculate the divisor for us.
 676	 */
 677#ifdef CONFIG_SERIAL_M32R_PLDSIO
 678	baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk/4);
 679#else
 680	baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk/16);
 681#endif
 682	quot = m32r_sio_get_divisor(port, baud);
 683
 684	/*
 685	 * Ok, we're now changing the port state.  Do it with
 686	 * interrupts disabled.
 687	 */
 688	spin_lock_irqsave(&up->port.lock, flags);
 689
 690	sio_set_baud_rate(baud);
 691
 692	/*
 693	 * Update the per-port timeout.
 694	 */
 695	uart_update_timeout(port, termios->c_cflag, baud);
 696
 697	up->port.read_status_mask = UART_LSR_OE | UART_LSR_THRE | UART_LSR_DR;
 698	if (termios->c_iflag & INPCK)
 699		up->port.read_status_mask |= UART_LSR_FE | UART_LSR_PE;
 700	if (termios->c_iflag & (IGNBRK | BRKINT | PARMRK))
 701		up->port.read_status_mask |= UART_LSR_BI;
 702
 703	/*
 704	 * Characteres to ignore
 705	 */
 706	up->port.ignore_status_mask = 0;
 707	if (termios->c_iflag & IGNPAR)
 708		up->port.ignore_status_mask |= UART_LSR_PE | UART_LSR_FE;
 709	if (termios->c_iflag & IGNBRK) {
 710		up->port.ignore_status_mask |= UART_LSR_BI;
 711		/*
 712		 * If we're ignoring parity and break indicators,
 713		 * ignore overruns too (for real raw support).
 714		 */
 715		if (termios->c_iflag & IGNPAR)
 716			up->port.ignore_status_mask |= UART_LSR_OE;
 717	}
 718
 719	/*
 720	 * ignore all characters if CREAD is not set
 721	 */
 722	if ((termios->c_cflag & CREAD) == 0)
 723		up->port.ignore_status_mask |= UART_LSR_DR;
 724
 725	/*
 726	 * CTS flow control flag and modem status interrupts
 727	 */
 728	up->ier &= ~UART_IER_MSI;
 729	if (UART_ENABLE_MS(&up->port, termios->c_cflag))
 730		up->ier |= UART_IER_MSI;
 731
 732	serial_out(up, UART_IER, up->ier);
 733
 734	spin_unlock_irqrestore(&up->port.lock, flags);
 735}
 736
 737/*
 738 * Resource handling.  This is complicated by the fact that resources
 739 * depend on the port type.  Maybe we should be claiming the standard
 740 * 8250 ports, and then trying to get other resources as necessary?
 741 */
 742static int
 743m32r_sio_request_std_resource(struct uart_sio_port *up, struct resource **res)
 744{
 745	unsigned int size = 8 << up->port.regshift;
 746#ifndef CONFIG_SERIAL_M32R_PLDSIO
 747	unsigned long start;
 748#endif
 749	int ret = 0;
 750
 751	switch (up->port.iotype) {
 752	case UPIO_MEM:
 753		if (up->port.mapbase) {
 754#ifdef CONFIG_SERIAL_M32R_PLDSIO
 755			*res = request_mem_region(up->port.mapbase, size, "serial");
 756#else
 757			start = up->port.mapbase;
 758			*res = request_mem_region(start, size, "serial");
 759#endif
 760			if (!*res)
 761				ret = -EBUSY;
 762		}
 763		break;
 764
 765	case UPIO_PORT:
 766		*res = request_region(up->port.iobase, size, "serial");
 767		if (!*res)
 768			ret = -EBUSY;
 769		break;
 770	}
 771	return ret;
 772}
 773
 774static void m32r_sio_release_port(struct uart_port *port)
 775{
 776	struct uart_sio_port *up =
 777		container_of(port, struct uart_sio_port, port);
 778	unsigned long start, offset = 0, size = 0;
 779
 780	size <<= up->port.regshift;
 781
 782	switch (up->port.iotype) {
 783	case UPIO_MEM:
 784		if (up->port.mapbase) {
 785			/*
 786			 * Unmap the area.
 787			 */
 788			iounmap(up->port.membase);
 789			up->port.membase = NULL;
 790
 791			start = up->port.mapbase;
 792
 793			if (size)
 794				release_mem_region(start + offset, size);
 795			release_mem_region(start, 8 << up->port.regshift);
 796		}
 797		break;
 798
 799	case UPIO_PORT:
 800		start = up->port.iobase;
 801
 802		if (size)
 803			release_region(start + offset, size);
 804		release_region(start + offset, 8 << up->port.regshift);
 805		break;
 806
 807	default:
 808		break;
 809	}
 810}
 811
 812static int m32r_sio_request_port(struct uart_port *port)
 813{
 814	struct uart_sio_port *up =
 815		container_of(port, struct uart_sio_port, port);
 816	struct resource *res = NULL;
 817	int ret = 0;
 818
 819	ret = m32r_sio_request_std_resource(up, &res);
 820
 821	/*
 822	 * If we have a mapbase, then request that as well.
 823	 */
 824	if (ret == 0 && up->port.flags & UPF_IOREMAP) {
 825		int size = resource_size(res);
 826
 827		up->port.membase = ioremap(up->port.mapbase, size);
 828		if (!up->port.membase)
 829			ret = -ENOMEM;
 830	}
 831
 832	if (ret < 0) {
 833		if (res)
 834			release_resource(res);
 835	}
 836
 837	return ret;
 838}
 839
 840static void m32r_sio_config_port(struct uart_port *port, int unused)
 841{
 842	struct uart_sio_port *up =
 843		container_of(port, struct uart_sio_port, port);
 844	unsigned long flags;
 845
 846	spin_lock_irqsave(&up->port.lock, flags);
 847
 848	up->port.fifosize = 1;
 849
 850	spin_unlock_irqrestore(&up->port.lock, flags);
 851}
 852
 853static int
 854m32r_sio_verify_port(struct uart_port *port, struct serial_struct *ser)
 855{
 856	if (ser->irq >= nr_irqs || ser->irq < 0 || ser->baud_base < 9600)
 857		return -EINVAL;
 858	return 0;
 859}
 860
 861static struct uart_ops m32r_sio_pops = {
 862	.tx_empty	= m32r_sio_tx_empty,
 863	.set_mctrl	= m32r_sio_set_mctrl,
 864	.get_mctrl	= m32r_sio_get_mctrl,
 865	.stop_tx	= m32r_sio_stop_tx,
 866	.start_tx	= m32r_sio_start_tx,
 867	.stop_rx	= m32r_sio_stop_rx,
 868	.enable_ms	= m32r_sio_enable_ms,
 869	.break_ctl	= m32r_sio_break_ctl,
 870	.startup	= m32r_sio_startup,
 871	.shutdown	= m32r_sio_shutdown,
 872	.set_termios	= m32r_sio_set_termios,
 873	.release_port	= m32r_sio_release_port,
 874	.request_port	= m32r_sio_request_port,
 875	.config_port	= m32r_sio_config_port,
 876	.verify_port	= m32r_sio_verify_port,
 877};
 878
 879static struct uart_sio_port m32r_sio_ports[UART_NR];
 880
 881static void __init m32r_sio_init_ports(void)
 882{
 883	struct uart_sio_port *up;
 884	static int first = 1;
 885	int i;
 886
 887	if (!first)
 888		return;
 889	first = 0;
 890
 891	for (i = 0, up = m32r_sio_ports; i < UART_NR; i++, up++) {
 892		up->port.iobase   = old_serial_port[i].port;
 893		up->port.irq      = irq_canonicalize(old_serial_port[i].irq);
 894		up->port.uartclk  = BAUD_RATE * 16;
 895		up->port.flags    = STD_COM_FLAGS;
 896		up->port.membase  = 0;
 897		up->port.iotype   = 0;
 898		up->port.regshift = 0;
 899		up->port.ops      = &m32r_sio_pops;
 900	}
 901}
 902
 903static void __init m32r_sio_register_ports(struct uart_driver *drv)
 904{
 905	int i;
 906
 907	m32r_sio_init_ports();
 908
 909	for (i = 0; i < UART_NR; i++) {
 910		struct uart_sio_port *up = &m32r_sio_ports[i];
 911
 912		up->port.line = i;
 913		up->port.ops = &m32r_sio_pops;
 914		init_timer(&up->timer);
 915		up->timer.function = m32r_sio_timeout;
 916
 917		uart_add_one_port(drv, &up->port);
 918	}
 919}
 920
 921#ifdef CONFIG_SERIAL_M32R_SIO_CONSOLE
 922
 923/*
 924 *	Wait for transmitter & holding register to empty
 925 */
 926static void wait_for_xmitr(struct uart_sio_port *up)
 927{
 928	unsigned int status, tmout = 10000;
 929
 930	/* Wait up to 10ms for the character(s) to be sent. */
 931	do {
 932		status = sio_in(up, SIOSTS);
 933
 934		if (--tmout == 0)
 935			break;
 936		udelay(1);
 937	} while ((status & UART_EMPTY) != UART_EMPTY);
 938
 939	/* Wait up to 1s for flow control if necessary */
 940	if (up->port.flags & UPF_CONS_FLOW) {
 941		tmout = 1000000;
 942		while (--tmout)
 943			udelay(1);
 944	}
 945}
 946
 947static void m32r_sio_console_putchar(struct uart_port *port, int ch)
 948{
 949	struct uart_sio_port *up =
 950		container_of(port, struct uart_sio_port, port);
 951
 952	wait_for_xmitr(up);
 953	sio_out(up, SIOTXB, ch);
 954}
 955
 956/*
 957 *	Print a string to the serial port trying not to disturb
 958 *	any possible real use of the port...
 959 *
 960 *	The console_lock must be held when we get here.
 961 */
 962static void m32r_sio_console_write(struct console *co, const char *s,
 963	unsigned int count)
 964{
 965	struct uart_sio_port *up = &m32r_sio_ports[co->index];
 966	unsigned int ier;
 967
 968	/*
 969	 *	First save the UER then disable the interrupts
 970	 */
 971	ier = sio_in(up, SIOTRCR);
 972	sio_out(up, SIOTRCR, 0);
 973
 974	uart_console_write(&up->port, s, count, m32r_sio_console_putchar);
 975
 976	/*
 977	 *	Finally, wait for transmitter to become empty
 978	 *	and restore the IER
 979	 */
 980	wait_for_xmitr(up);
 981	sio_out(up, SIOTRCR, ier);
 982}
 983
 984static int __init m32r_sio_console_setup(struct console *co, char *options)
 985{
 986	struct uart_port *port;
 987	int baud = 9600;
 988	int bits = 8;
 989	int parity = 'n';
 990	int flow = 'n';
 991
 992	/*
 993	 * Check whether an invalid uart number has been specified, and
 994	 * if so, search for the first available port that does have
 995	 * console support.
 996	 */
 997	if (co->index >= UART_NR)
 998		co->index = 0;
 999	port = &m32r_sio_ports[co->index].port;
1000
1001	/*
1002	 * Temporary fix.
1003	 */
1004	spin_lock_init(&port->lock);
1005
1006	if (options)
1007		uart_parse_options(options, &baud, &parity, &bits, &flow);
1008
1009	return uart_set_options(port, co, baud, parity, bits, flow);
1010}
1011
1012static struct uart_driver m32r_sio_reg;
1013static struct console m32r_sio_console = {
1014	.name		= "ttyS",
1015	.write		= m32r_sio_console_write,
1016	.device		= uart_console_device,
1017	.setup		= m32r_sio_console_setup,
1018	.flags		= CON_PRINTBUFFER,
1019	.index		= -1,
1020	.data		= &m32r_sio_reg,
1021};
1022
1023static int __init m32r_sio_console_init(void)
1024{
1025	sio_reset();
1026	sio_init();
1027	m32r_sio_init_ports();
1028	register_console(&m32r_sio_console);
1029	return 0;
1030}
1031console_initcall(m32r_sio_console_init);
1032
1033#define M32R_SIO_CONSOLE	&m32r_sio_console
1034#else
1035#define M32R_SIO_CONSOLE	NULL
1036#endif
1037
1038static struct uart_driver m32r_sio_reg = {
1039	.owner			= THIS_MODULE,
1040	.driver_name		= "sio",
1041	.dev_name		= "ttyS",
1042	.major			= TTY_MAJOR,
1043	.minor			= 64,
1044	.nr			= UART_NR,
1045	.cons			= M32R_SIO_CONSOLE,
1046};
1047
1048static int __init m32r_sio_init(void)
1049{
1050	int ret, i;
1051
1052	printk(KERN_INFO "Serial: M32R SIO driver\n");
1053
1054	for (i = 0; i < nr_irqs; i++)
1055		spin_lock_init(&irq_lists[i].lock);
1056
1057	ret = uart_register_driver(&m32r_sio_reg);
1058	if (ret >= 0)
1059		m32r_sio_register_ports(&m32r_sio_reg);
1060
1061	return ret;
1062}
1063
1064static void __exit m32r_sio_exit(void)
1065{
1066	int i;
1067
1068	for (i = 0; i < UART_NR; i++)
1069		uart_remove_one_port(&m32r_sio_reg, &m32r_sio_ports[i].port);
1070
1071	uart_unregister_driver(&m32r_sio_reg);
1072}
1073
1074module_init(m32r_sio_init);
1075module_exit(m32r_sio_exit);
1076
1077MODULE_LICENSE("GPL");
1078MODULE_DESCRIPTION("Generic M32R SIO serial driver");