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v6.2
   1// SPDX-License-Identifier: GPL-2.0
   2/* sunsab.c: ASYNC Driver for the SIEMENS SAB82532 DUSCC.
   3 *
   4 * Copyright (C) 1997  Eddie C. Dost  (ecd@skynet.be)
   5 * Copyright (C) 2002, 2006  David S. Miller (davem@davemloft.net)
   6 *
   7 * Rewrote buffer handling to use CIRC(Circular Buffer) macros.
   8 *   Maxim Krasnyanskiy <maxk@qualcomm.com>
   9 *
  10 * Fixed to use tty_get_baud_rate, and to allow for arbitrary baud
  11 * rates to be programmed into the UART.  Also eliminated a lot of
  12 * duplicated code in the console setup.
  13 *   Theodore Ts'o <tytso@mit.edu>, 2001-Oct-12
  14 *
  15 * Ported to new 2.5.x UART layer.
  16 *   David S. Miller <davem@davemloft.net>
  17 */
  18
  19#include <linux/module.h>
  20#include <linux/kernel.h>
  21#include <linux/errno.h>
  22#include <linux/tty.h>
  23#include <linux/tty_flip.h>
  24#include <linux/major.h>
  25#include <linux/string.h>
  26#include <linux/ptrace.h>
  27#include <linux/ioport.h>
  28#include <linux/circ_buf.h>
  29#include <linux/serial.h>
  30#include <linux/sysrq.h>
  31#include <linux/console.h>
  32#include <linux/spinlock.h>
  33#include <linux/slab.h>
  34#include <linux/delay.h>
  35#include <linux/init.h>
  36#include <linux/of_device.h>
  37
  38#include <linux/io.h>
  39#include <asm/irq.h>
  40#include <asm/prom.h>
  41#include <asm/setup.h>
  42
 
 
 
 
  43#include <linux/serial_core.h>
  44#include <linux/sunserialcore.h>
  45
  46#include "sunsab.h"
  47
  48struct uart_sunsab_port {
  49	struct uart_port		port;		/* Generic UART port	*/
  50	union sab82532_async_regs	__iomem *regs;	/* Chip registers	*/
  51	unsigned long			irqflags;	/* IRQ state flags	*/
  52	int				dsr;		/* Current DSR state	*/
  53	unsigned int			cec_timeout;	/* Chip poll timeout... */
  54	unsigned int			tec_timeout;	/* likewise		*/
  55	unsigned char			interrupt_mask0;/* ISR0 masking		*/
  56	unsigned char			interrupt_mask1;/* ISR1 masking		*/
  57	unsigned char			pvr_dtr_bit;	/* Which PVR bit is DTR */
  58	unsigned char			pvr_dsr_bit;	/* Which PVR bit is DSR */
  59	unsigned int			gis_shift;
  60	int				type;		/* SAB82532 version	*/
  61
  62	/* Setting configuration bits while the transmitter is active
  63	 * can cause garbage characters to get emitted by the chip.
  64	 * Therefore, we cache such writes here and do the real register
  65	 * write the next time the transmitter becomes idle.
  66	 */
  67	unsigned int			cached_ebrg;
  68	unsigned char			cached_mode;
  69	unsigned char			cached_pvr;
  70	unsigned char			cached_dafo;
  71};
  72
  73/*
  74 * This assumes you have a 29.4912 MHz clock for your UART.
  75 */
  76#define SAB_BASE_BAUD ( 29491200 / 16 )
  77
  78static char *sab82532_version[16] = {
  79	"V1.0", "V2.0", "V3.2", "V(0x03)",
  80	"V(0x04)", "V(0x05)", "V(0x06)", "V(0x07)",
  81	"V(0x08)", "V(0x09)", "V(0x0a)", "V(0x0b)",
  82	"V(0x0c)", "V(0x0d)", "V(0x0e)", "V(0x0f)"
  83};
  84
  85#define SAB82532_MAX_TEC_TIMEOUT 200000	/* 1 character time (at 50 baud) */
  86#define SAB82532_MAX_CEC_TIMEOUT  50000	/* 2.5 TX CLKs (at 50 baud) */
  87
  88#define SAB82532_RECV_FIFO_SIZE	32      /* Standard async fifo sizes */
  89#define SAB82532_XMIT_FIFO_SIZE	32
  90
  91static __inline__ void sunsab_tec_wait(struct uart_sunsab_port *up)
  92{
  93	int timeout = up->tec_timeout;
  94
  95	while ((readb(&up->regs->r.star) & SAB82532_STAR_TEC) && --timeout)
  96		udelay(1);
  97}
  98
  99static __inline__ void sunsab_cec_wait(struct uart_sunsab_port *up)
 100{
 101	int timeout = up->cec_timeout;
 102
 103	while ((readb(&up->regs->r.star) & SAB82532_STAR_CEC) && --timeout)
 104		udelay(1);
 105}
 106
 107static struct tty_port *
 108receive_chars(struct uart_sunsab_port *up,
 109	      union sab82532_irq_status *stat)
 110{
 111	struct tty_port *port = NULL;
 112	unsigned char buf[32];
 113	int saw_console_brk = 0;
 114	int free_fifo = 0;
 115	int count = 0;
 116	int i;
 117
 118	if (up->port.state != NULL)		/* Unopened serial console */
 119		port = &up->port.state->port;
 120
 121	/* Read number of BYTES (Character + Status) available. */
 122	if (stat->sreg.isr0 & SAB82532_ISR0_RPF) {
 123		count = SAB82532_RECV_FIFO_SIZE;
 124		free_fifo++;
 125	}
 126
 127	if (stat->sreg.isr0 & SAB82532_ISR0_TCD) {
 128		count = readb(&up->regs->r.rbcl) & (SAB82532_RECV_FIFO_SIZE - 1);
 129		free_fifo++;
 130	}
 131
 132	/* Issue a FIFO read command in case we where idle. */
 133	if (stat->sreg.isr0 & SAB82532_ISR0_TIME) {
 134		sunsab_cec_wait(up);
 135		writeb(SAB82532_CMDR_RFRD, &up->regs->w.cmdr);
 136		return port;
 137	}
 138
 139	if (stat->sreg.isr0 & SAB82532_ISR0_RFO)
 140		free_fifo++;
 141
 142	/* Read the FIFO. */
 143	for (i = 0; i < count; i++)
 144		buf[i] = readb(&up->regs->r.rfifo[i]);
 145
 146	/* Issue Receive Message Complete command. */
 147	if (free_fifo) {
 148		sunsab_cec_wait(up);
 149		writeb(SAB82532_CMDR_RMC, &up->regs->w.cmdr);
 150	}
 151
 152	/* Count may be zero for BRK, so we check for it here */
 153	if ((stat->sreg.isr1 & SAB82532_ISR1_BRK) &&
 154	    (up->port.line == up->port.cons->index))
 155		saw_console_brk = 1;
 156
 157	if (count == 0) {
 158		if (unlikely(stat->sreg.isr1 & SAB82532_ISR1_BRK)) {
 159			stat->sreg.isr0 &= ~(SAB82532_ISR0_PERR |
 160					     SAB82532_ISR0_FERR);
 161			up->port.icount.brk++;
 162			uart_handle_break(&up->port);
 163		}
 164	}
 165
 166	for (i = 0; i < count; i++) {
 167		unsigned char ch = buf[i], flag;
 168
 
 
 
 
 
 169		flag = TTY_NORMAL;
 170		up->port.icount.rx++;
 171
 172		if (unlikely(stat->sreg.isr0 & (SAB82532_ISR0_PERR |
 173						SAB82532_ISR0_FERR |
 174						SAB82532_ISR0_RFO)) ||
 175		    unlikely(stat->sreg.isr1 & SAB82532_ISR1_BRK)) {
 176			/*
 177			 * For statistics only
 178			 */
 179			if (stat->sreg.isr1 & SAB82532_ISR1_BRK) {
 180				stat->sreg.isr0 &= ~(SAB82532_ISR0_PERR |
 181						     SAB82532_ISR0_FERR);
 182				up->port.icount.brk++;
 183				/*
 184				 * We do the SysRQ and SAK checking
 185				 * here because otherwise the break
 186				 * may get masked by ignore_status_mask
 187				 * or read_status_mask.
 188				 */
 189				if (uart_handle_break(&up->port))
 190					continue;
 191			} else if (stat->sreg.isr0 & SAB82532_ISR0_PERR)
 192				up->port.icount.parity++;
 193			else if (stat->sreg.isr0 & SAB82532_ISR0_FERR)
 194				up->port.icount.frame++;
 195			if (stat->sreg.isr0 & SAB82532_ISR0_RFO)
 196				up->port.icount.overrun++;
 197
 198			/*
 199			 * Mask off conditions which should be ingored.
 200			 */
 201			stat->sreg.isr0 &= (up->port.read_status_mask & 0xff);
 202			stat->sreg.isr1 &= ((up->port.read_status_mask >> 8) & 0xff);
 203
 204			if (stat->sreg.isr1 & SAB82532_ISR1_BRK) {
 205				flag = TTY_BREAK;
 206			} else if (stat->sreg.isr0 & SAB82532_ISR0_PERR)
 207				flag = TTY_PARITY;
 208			else if (stat->sreg.isr0 & SAB82532_ISR0_FERR)
 209				flag = TTY_FRAME;
 210		}
 211
 212		if (uart_handle_sysrq_char(&up->port, ch) || !port)
 213			continue;
 214
 215		if ((stat->sreg.isr0 & (up->port.ignore_status_mask & 0xff)) == 0 &&
 216		    (stat->sreg.isr1 & ((up->port.ignore_status_mask >> 8) & 0xff)) == 0)
 217			tty_insert_flip_char(port, ch, flag);
 218		if (stat->sreg.isr0 & SAB82532_ISR0_RFO)
 219			tty_insert_flip_char(port, 0, TTY_OVERRUN);
 220	}
 221
 222	if (saw_console_brk)
 223		sun_do_break();
 224
 225	return port;
 226}
 227
 228static void sunsab_stop_tx(struct uart_port *);
 229static void sunsab_tx_idle(struct uart_sunsab_port *);
 230
 231static void transmit_chars(struct uart_sunsab_port *up,
 232			   union sab82532_irq_status *stat)
 233{
 234	struct circ_buf *xmit = &up->port.state->xmit;
 235	int i;
 236
 237	if (stat->sreg.isr1 & SAB82532_ISR1_ALLS) {
 238		up->interrupt_mask1 |= SAB82532_IMR1_ALLS;
 239		writeb(up->interrupt_mask1, &up->regs->w.imr1);
 240		set_bit(SAB82532_ALLS, &up->irqflags);
 241	}
 242
 243#if 0 /* bde@nwlink.com says this check causes problems */
 244	if (!(stat->sreg.isr1 & SAB82532_ISR1_XPR))
 245		return;
 246#endif
 247
 248	if (!(readb(&up->regs->r.star) & SAB82532_STAR_XFW))
 249		return;
 250
 251	set_bit(SAB82532_XPR, &up->irqflags);
 252	sunsab_tx_idle(up);
 253
 254	if (uart_circ_empty(xmit) || uart_tx_stopped(&up->port)) {
 255		up->interrupt_mask1 |= SAB82532_IMR1_XPR;
 256		writeb(up->interrupt_mask1, &up->regs->w.imr1);
 257		return;
 258	}
 259
 260	up->interrupt_mask1 &= ~(SAB82532_IMR1_ALLS|SAB82532_IMR1_XPR);
 261	writeb(up->interrupt_mask1, &up->regs->w.imr1);
 262	clear_bit(SAB82532_ALLS, &up->irqflags);
 263
 264	/* Stuff 32 bytes into Transmit FIFO. */
 265	clear_bit(SAB82532_XPR, &up->irqflags);
 266	for (i = 0; i < up->port.fifosize; i++) {
 267		writeb(xmit->buf[xmit->tail],
 268		       &up->regs->w.xfifo[i]);
 269		uart_xmit_advance(&up->port, 1);
 
 270		if (uart_circ_empty(xmit))
 271			break;
 272	}
 273
 274	/* Issue a Transmit Frame command. */
 275	sunsab_cec_wait(up);
 276	writeb(SAB82532_CMDR_XF, &up->regs->w.cmdr);
 277
 278	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
 279		uart_write_wakeup(&up->port);
 280
 281	if (uart_circ_empty(xmit))
 282		sunsab_stop_tx(&up->port);
 283}
 284
 285static void check_status(struct uart_sunsab_port *up,
 286			 union sab82532_irq_status *stat)
 287{
 288	if (stat->sreg.isr0 & SAB82532_ISR0_CDSC)
 289		uart_handle_dcd_change(&up->port,
 290				       !(readb(&up->regs->r.vstr) & SAB82532_VSTR_CD));
 291
 292	if (stat->sreg.isr1 & SAB82532_ISR1_CSC)
 293		uart_handle_cts_change(&up->port,
 294				       (readb(&up->regs->r.star) & SAB82532_STAR_CTS));
 295
 296	if ((readb(&up->regs->r.pvr) & up->pvr_dsr_bit) ^ up->dsr) {
 297		up->dsr = (readb(&up->regs->r.pvr) & up->pvr_dsr_bit) ? 0 : 1;
 298		up->port.icount.dsr++;
 299	}
 300
 301	wake_up_interruptible(&up->port.state->port.delta_msr_wait);
 302}
 303
 304static irqreturn_t sunsab_interrupt(int irq, void *dev_id)
 305{
 306	struct uart_sunsab_port *up = dev_id;
 307	struct tty_port *port = NULL;
 308	union sab82532_irq_status status;
 309	unsigned long flags;
 310	unsigned char gis;
 311
 312	spin_lock_irqsave(&up->port.lock, flags);
 313
 314	status.stat = 0;
 315	gis = readb(&up->regs->r.gis) >> up->gis_shift;
 316	if (gis & 1)
 317		status.sreg.isr0 = readb(&up->regs->r.isr0);
 318	if (gis & 2)
 319		status.sreg.isr1 = readb(&up->regs->r.isr1);
 320
 
 321	if (status.stat) {
 322		if ((status.sreg.isr0 & (SAB82532_ISR0_TCD | SAB82532_ISR0_TIME |
 323					 SAB82532_ISR0_RFO | SAB82532_ISR0_RPF)) ||
 324		    (status.sreg.isr1 & SAB82532_ISR1_BRK))
 325			port = receive_chars(up, &status);
 326		if ((status.sreg.isr0 & SAB82532_ISR0_CDSC) ||
 327		    (status.sreg.isr1 & SAB82532_ISR1_CSC))
 328			check_status(up, &status);
 329		if (status.sreg.isr1 & (SAB82532_ISR1_ALLS | SAB82532_ISR1_XPR))
 330			transmit_chars(up, &status);
 331	}
 332
 333	spin_unlock_irqrestore(&up->port.lock, flags);
 334
 335	if (port)
 336		tty_flip_buffer_push(port);
 337
 338	return IRQ_HANDLED;
 339}
 340
 341/* port->lock is not held.  */
 342static unsigned int sunsab_tx_empty(struct uart_port *port)
 343{
 344	struct uart_sunsab_port *up =
 345		container_of(port, struct uart_sunsab_port, port);
 346	int ret;
 347
 348	/* Do not need a lock for a state test like this.  */
 349	if (test_bit(SAB82532_ALLS, &up->irqflags))
 350		ret = TIOCSER_TEMT;
 351	else
 352		ret = 0;
 353
 354	return ret;
 355}
 356
 357/* port->lock held by caller.  */
 358static void sunsab_set_mctrl(struct uart_port *port, unsigned int mctrl)
 359{
 360	struct uart_sunsab_port *up =
 361		container_of(port, struct uart_sunsab_port, port);
 362
 363	if (mctrl & TIOCM_RTS) {
 364		up->cached_mode &= ~SAB82532_MODE_FRTS;
 365		up->cached_mode |= SAB82532_MODE_RTS;
 366	} else {
 367		up->cached_mode |= (SAB82532_MODE_FRTS |
 368				    SAB82532_MODE_RTS);
 369	}
 370	if (mctrl & TIOCM_DTR) {
 371		up->cached_pvr &= ~(up->pvr_dtr_bit);
 372	} else {
 373		up->cached_pvr |= up->pvr_dtr_bit;
 374	}
 375
 376	set_bit(SAB82532_REGS_PENDING, &up->irqflags);
 377	if (test_bit(SAB82532_XPR, &up->irqflags))
 378		sunsab_tx_idle(up);
 379}
 380
 381/* port->lock is held by caller and interrupts are disabled.  */
 382static unsigned int sunsab_get_mctrl(struct uart_port *port)
 383{
 384	struct uart_sunsab_port *up =
 385		container_of(port, struct uart_sunsab_port, port);
 386	unsigned char val;
 387	unsigned int result;
 388
 389	result = 0;
 390
 391	val = readb(&up->regs->r.pvr);
 392	result |= (val & up->pvr_dsr_bit) ? 0 : TIOCM_DSR;
 393
 394	val = readb(&up->regs->r.vstr);
 395	result |= (val & SAB82532_VSTR_CD) ? 0 : TIOCM_CAR;
 396
 397	val = readb(&up->regs->r.star);
 398	result |= (val & SAB82532_STAR_CTS) ? TIOCM_CTS : 0;
 399
 400	return result;
 401}
 402
 403/* port->lock held by caller.  */
 404static void sunsab_stop_tx(struct uart_port *port)
 405{
 406	struct uart_sunsab_port *up =
 407		container_of(port, struct uart_sunsab_port, port);
 408
 409	up->interrupt_mask1 |= SAB82532_IMR1_XPR;
 410	writeb(up->interrupt_mask1, &up->regs->w.imr1);
 411}
 412
 413/* port->lock held by caller.  */
 414static void sunsab_tx_idle(struct uart_sunsab_port *up)
 415{
 416	if (test_bit(SAB82532_REGS_PENDING, &up->irqflags)) {
 417		u8 tmp;
 418
 419		clear_bit(SAB82532_REGS_PENDING, &up->irqflags);
 420		writeb(up->cached_mode, &up->regs->rw.mode);
 421		writeb(up->cached_pvr, &up->regs->rw.pvr);
 422		writeb(up->cached_dafo, &up->regs->w.dafo);
 423
 424		writeb(up->cached_ebrg & 0xff, &up->regs->w.bgr);
 425		tmp = readb(&up->regs->rw.ccr2);
 426		tmp &= ~0xc0;
 427		tmp |= (up->cached_ebrg >> 2) & 0xc0;
 428		writeb(tmp, &up->regs->rw.ccr2);
 429	}
 430}
 431
 432/* port->lock held by caller.  */
 433static void sunsab_start_tx(struct uart_port *port)
 434{
 435	struct uart_sunsab_port *up =
 436		container_of(port, struct uart_sunsab_port, port);
 437	struct circ_buf *xmit = &up->port.state->xmit;
 438	int i;
 439
 440	if (uart_circ_empty(xmit) || uart_tx_stopped(port))
 441		return;
 442
 443	up->interrupt_mask1 &= ~(SAB82532_IMR1_ALLS|SAB82532_IMR1_XPR);
 444	writeb(up->interrupt_mask1, &up->regs->w.imr1);
 445	
 446	if (!test_bit(SAB82532_XPR, &up->irqflags))
 447		return;
 448
 449	clear_bit(SAB82532_ALLS, &up->irqflags);
 450	clear_bit(SAB82532_XPR, &up->irqflags);
 451
 452	for (i = 0; i < up->port.fifosize; i++) {
 453		writeb(xmit->buf[xmit->tail],
 454		       &up->regs->w.xfifo[i]);
 455		uart_xmit_advance(&up->port, 1);
 
 456		if (uart_circ_empty(xmit))
 457			break;
 458	}
 459
 460	/* Issue a Transmit Frame command.  */
 461	sunsab_cec_wait(up);
 462	writeb(SAB82532_CMDR_XF, &up->regs->w.cmdr);
 463}
 464
 465/* port->lock is not held.  */
 466static void sunsab_send_xchar(struct uart_port *port, char ch)
 467{
 468	struct uart_sunsab_port *up =
 469		container_of(port, struct uart_sunsab_port, port);
 470	unsigned long flags;
 471
 472	if (ch == __DISABLED_CHAR)
 473		return;
 474
 475	spin_lock_irqsave(&up->port.lock, flags);
 476
 477	sunsab_tec_wait(up);
 478	writeb(ch, &up->regs->w.tic);
 479
 480	spin_unlock_irqrestore(&up->port.lock, flags);
 481}
 482
 483/* port->lock held by caller.  */
 484static void sunsab_stop_rx(struct uart_port *port)
 485{
 486	struct uart_sunsab_port *up =
 487		container_of(port, struct uart_sunsab_port, port);
 488
 489	up->interrupt_mask0 |= SAB82532_IMR0_TCD;
 490	writeb(up->interrupt_mask1, &up->regs->w.imr0);
 491}
 492
 
 
 
 
 
 
 493/* port->lock is not held.  */
 494static void sunsab_break_ctl(struct uart_port *port, int break_state)
 495{
 496	struct uart_sunsab_port *up =
 497		container_of(port, struct uart_sunsab_port, port);
 498	unsigned long flags;
 499	unsigned char val;
 500
 501	spin_lock_irqsave(&up->port.lock, flags);
 502
 503	val = up->cached_dafo;
 504	if (break_state)
 505		val |= SAB82532_DAFO_XBRK;
 506	else
 507		val &= ~SAB82532_DAFO_XBRK;
 508	up->cached_dafo = val;
 509
 510	set_bit(SAB82532_REGS_PENDING, &up->irqflags);
 511	if (test_bit(SAB82532_XPR, &up->irqflags))
 512		sunsab_tx_idle(up);
 513
 514	spin_unlock_irqrestore(&up->port.lock, flags);
 515}
 516
 517/* port->lock is not held.  */
 518static int sunsab_startup(struct uart_port *port)
 519{
 520	struct uart_sunsab_port *up =
 521		container_of(port, struct uart_sunsab_port, port);
 522	unsigned long flags;
 523	unsigned char tmp;
 524	int err = request_irq(up->port.irq, sunsab_interrupt,
 525			      IRQF_SHARED, "sab", up);
 526	if (err)
 527		return err;
 528
 529	spin_lock_irqsave(&up->port.lock, flags);
 530
 531	/*
 532	 * Wait for any commands or immediate characters
 533	 */
 534	sunsab_cec_wait(up);
 535	sunsab_tec_wait(up);
 536
 537	/*
 538	 * Clear the FIFO buffers.
 539	 */
 540	writeb(SAB82532_CMDR_RRES, &up->regs->w.cmdr);
 541	sunsab_cec_wait(up);
 542	writeb(SAB82532_CMDR_XRES, &up->regs->w.cmdr);
 543
 544	/*
 545	 * Clear the interrupt registers.
 546	 */
 547	(void) readb(&up->regs->r.isr0);
 548	(void) readb(&up->regs->r.isr1);
 549
 550	/*
 551	 * Now, initialize the UART 
 552	 */
 553	writeb(0, &up->regs->w.ccr0);				/* power-down */
 554	writeb(SAB82532_CCR0_MCE | SAB82532_CCR0_SC_NRZ |
 555	       SAB82532_CCR0_SM_ASYNC, &up->regs->w.ccr0);
 556	writeb(SAB82532_CCR1_ODS | SAB82532_CCR1_BCR | 7, &up->regs->w.ccr1);
 557	writeb(SAB82532_CCR2_BDF | SAB82532_CCR2_SSEL |
 558	       SAB82532_CCR2_TOE, &up->regs->w.ccr2);
 559	writeb(0, &up->regs->w.ccr3);
 560	writeb(SAB82532_CCR4_MCK4 | SAB82532_CCR4_EBRG, &up->regs->w.ccr4);
 561	up->cached_mode = (SAB82532_MODE_RTS | SAB82532_MODE_FCTS |
 562			   SAB82532_MODE_RAC);
 563	writeb(up->cached_mode, &up->regs->w.mode);
 564	writeb(SAB82532_RFC_DPS|SAB82532_RFC_RFTH_32, &up->regs->w.rfc);
 565	
 566	tmp = readb(&up->regs->rw.ccr0);
 567	tmp |= SAB82532_CCR0_PU;	/* power-up */
 568	writeb(tmp, &up->regs->rw.ccr0);
 569
 570	/*
 571	 * Finally, enable interrupts
 572	 */
 573	up->interrupt_mask0 = (SAB82532_IMR0_PERR | SAB82532_IMR0_FERR |
 574			       SAB82532_IMR0_PLLA);
 575	writeb(up->interrupt_mask0, &up->regs->w.imr0);
 576	up->interrupt_mask1 = (SAB82532_IMR1_BRKT | SAB82532_IMR1_ALLS |
 577			       SAB82532_IMR1_XOFF | SAB82532_IMR1_TIN |
 578			       SAB82532_IMR1_CSC | SAB82532_IMR1_XON |
 579			       SAB82532_IMR1_XPR);
 580	writeb(up->interrupt_mask1, &up->regs->w.imr1);
 581	set_bit(SAB82532_ALLS, &up->irqflags);
 582	set_bit(SAB82532_XPR, &up->irqflags);
 583
 584	spin_unlock_irqrestore(&up->port.lock, flags);
 585
 586	return 0;
 587}
 588
 589/* port->lock is not held.  */
 590static void sunsab_shutdown(struct uart_port *port)
 591{
 592	struct uart_sunsab_port *up =
 593		container_of(port, struct uart_sunsab_port, port);
 594	unsigned long flags;
 595
 596	spin_lock_irqsave(&up->port.lock, flags);
 597
 598	/* Disable Interrupts */
 599	up->interrupt_mask0 = 0xff;
 600	writeb(up->interrupt_mask0, &up->regs->w.imr0);
 601	up->interrupt_mask1 = 0xff;
 602	writeb(up->interrupt_mask1, &up->regs->w.imr1);
 603
 604	/* Disable break condition */
 605	up->cached_dafo = readb(&up->regs->rw.dafo);
 606	up->cached_dafo &= ~SAB82532_DAFO_XBRK;
 607	writeb(up->cached_dafo, &up->regs->rw.dafo);
 608
 609	/* Disable Receiver */	
 610	up->cached_mode &= ~SAB82532_MODE_RAC;
 611	writeb(up->cached_mode, &up->regs->rw.mode);
 612
 613	/*
 614	 * XXX FIXME
 615	 *
 616	 * If the chip is powered down here the system hangs/crashes during
 617	 * reboot or shutdown.  This needs to be investigated further,
 618	 * similar behaviour occurs in 2.4 when the driver is configured
 619	 * as a module only.  One hint may be that data is sometimes
 620	 * transmitted at 9600 baud during shutdown (regardless of the
 621	 * speed the chip was configured for when the port was open).
 622	 */
 623#if 0
 624	/* Power Down */	
 625	tmp = readb(&up->regs->rw.ccr0);
 626	tmp &= ~SAB82532_CCR0_PU;
 627	writeb(tmp, &up->regs->rw.ccr0);
 628#endif
 629
 630	spin_unlock_irqrestore(&up->port.lock, flags);
 631	free_irq(up->port.irq, up);
 632}
 633
 634/*
 635 * This is used to figure out the divisor speeds.
 636 *
 637 * The formula is:    Baud = SAB_BASE_BAUD / ((N + 1) * (1 << M)),
 638 *
 639 * with               0 <= N < 64 and 0 <= M < 16
 640 */
 641
 642static void calc_ebrg(int baud, int *n_ret, int *m_ret)
 643{
 644	int	n, m;
 645
 646	if (baud == 0) {
 647		*n_ret = 0;
 648		*m_ret = 0;
 649		return;
 650	}
 651     
 652	/*
 653	 * We scale numbers by 10 so that we get better accuracy
 654	 * without having to use floating point.  Here we increment m
 655	 * until n is within the valid range.
 656	 */
 657	n = (SAB_BASE_BAUD * 10) / baud;
 658	m = 0;
 659	while (n >= 640) {
 660		n = n / 2;
 661		m++;
 662	}
 663	n = (n+5) / 10;
 664	/*
 665	 * We try very hard to avoid speeds with M == 0 since they may
 666	 * not work correctly for XTAL frequences above 10 MHz.
 667	 */
 668	if ((m == 0) && ((n & 1) == 0)) {
 669		n = n / 2;
 670		m++;
 671	}
 672	*n_ret = n - 1;
 673	*m_ret = m;
 674}
 675
 676/* Internal routine, port->lock is held and local interrupts are disabled.  */
 677static void sunsab_convert_to_sab(struct uart_sunsab_port *up, unsigned int cflag,
 678				  unsigned int iflag, unsigned int baud,
 679				  unsigned int quot)
 680{
 681	unsigned char dafo;
 682	int n, m;
 683
 684	/* Byte size and parity */
 685	switch (cflag & CSIZE) {
 686	      case CS5: dafo = SAB82532_DAFO_CHL5; break;
 687	      case CS6: dafo = SAB82532_DAFO_CHL6; break;
 688	      case CS7: dafo = SAB82532_DAFO_CHL7; break;
 689	      case CS8: dafo = SAB82532_DAFO_CHL8; break;
 690	      /* Never happens, but GCC is too dumb to figure it out */
 691	      default:  dafo = SAB82532_DAFO_CHL5; break;
 692	}
 693
 694	if (cflag & CSTOPB)
 695		dafo |= SAB82532_DAFO_STOP;
 
 
 696
 697	if (cflag & PARENB)
 698		dafo |= SAB82532_DAFO_PARE;
 
 
 699
 700	if (cflag & PARODD) {
 701		dafo |= SAB82532_DAFO_PAR_ODD;
 702	} else {
 703		dafo |= SAB82532_DAFO_PAR_EVEN;
 704	}
 705	up->cached_dafo = dafo;
 706
 707	calc_ebrg(baud, &n, &m);
 708
 709	up->cached_ebrg = n | (m << 6);
 710
 711	up->tec_timeout = (10 * 1000000) / baud;
 712	up->cec_timeout = up->tec_timeout >> 2;
 713
 714	/* CTS flow control flags */
 715	/* We encode read_status_mask and ignore_status_mask like so:
 716	 *
 717	 * ---------------------
 718	 * | ... | ISR1 | ISR0 |
 719	 * ---------------------
 720	 *  ..    15   8 7    0
 721	 */
 722
 723	up->port.read_status_mask = (SAB82532_ISR0_TCD | SAB82532_ISR0_TIME |
 724				     SAB82532_ISR0_RFO | SAB82532_ISR0_RPF |
 725				     SAB82532_ISR0_CDSC);
 726	up->port.read_status_mask |= (SAB82532_ISR1_CSC |
 727				      SAB82532_ISR1_ALLS |
 728				      SAB82532_ISR1_XPR) << 8;
 729	if (iflag & INPCK)
 730		up->port.read_status_mask |= (SAB82532_ISR0_PERR |
 731					      SAB82532_ISR0_FERR);
 732	if (iflag & (IGNBRK | BRKINT | PARMRK))
 733		up->port.read_status_mask |= (SAB82532_ISR1_BRK << 8);
 734
 735	/*
 736	 * Characteres to ignore
 737	 */
 738	up->port.ignore_status_mask = 0;
 739	if (iflag & IGNPAR)
 740		up->port.ignore_status_mask |= (SAB82532_ISR0_PERR |
 741						SAB82532_ISR0_FERR);
 742	if (iflag & IGNBRK) {
 743		up->port.ignore_status_mask |= (SAB82532_ISR1_BRK << 8);
 744		/*
 745		 * If we're ignoring parity and break indicators,
 746		 * ignore overruns too (for real raw support).
 747		 */
 748		if (iflag & IGNPAR)
 749			up->port.ignore_status_mask |= SAB82532_ISR0_RFO;
 750	}
 751
 752	/*
 753	 * ignore all characters if CREAD is not set
 754	 */
 755	if ((cflag & CREAD) == 0)
 756		up->port.ignore_status_mask |= (SAB82532_ISR0_RPF |
 757						SAB82532_ISR0_TCD);
 758
 759	uart_update_timeout(&up->port, cflag,
 760			    (up->port.uartclk / (16 * quot)));
 761
 762	/* Now schedule a register update when the chip's
 763	 * transmitter is idle.
 764	 */
 765	up->cached_mode |= SAB82532_MODE_RAC;
 766	set_bit(SAB82532_REGS_PENDING, &up->irqflags);
 767	if (test_bit(SAB82532_XPR, &up->irqflags))
 768		sunsab_tx_idle(up);
 769}
 770
 771/* port->lock is not held.  */
 772static void sunsab_set_termios(struct uart_port *port, struct ktermios *termios,
 773			       const struct ktermios *old)
 774{
 775	struct uart_sunsab_port *up =
 776		container_of(port, struct uart_sunsab_port, port);
 777	unsigned long flags;
 778	unsigned int baud = uart_get_baud_rate(port, termios, old, 0, 4000000);
 779	unsigned int quot = uart_get_divisor(port, baud);
 780
 781	spin_lock_irqsave(&up->port.lock, flags);
 782	sunsab_convert_to_sab(up, termios->c_cflag, termios->c_iflag, baud, quot);
 783	spin_unlock_irqrestore(&up->port.lock, flags);
 784}
 785
 786static const char *sunsab_type(struct uart_port *port)
 787{
 788	struct uart_sunsab_port *up = (void *)port;
 789	static char buf[36];
 790	
 791	sprintf(buf, "SAB82532 %s", sab82532_version[up->type]);
 792	return buf;
 793}
 794
 795static void sunsab_release_port(struct uart_port *port)
 796{
 797}
 798
 799static int sunsab_request_port(struct uart_port *port)
 800{
 801	return 0;
 802}
 803
 804static void sunsab_config_port(struct uart_port *port, int flags)
 805{
 806}
 807
 808static int sunsab_verify_port(struct uart_port *port, struct serial_struct *ser)
 809{
 810	return -EINVAL;
 811}
 812
 813static const struct uart_ops sunsab_pops = {
 814	.tx_empty	= sunsab_tx_empty,
 815	.set_mctrl	= sunsab_set_mctrl,
 816	.get_mctrl	= sunsab_get_mctrl,
 817	.stop_tx	= sunsab_stop_tx,
 818	.start_tx	= sunsab_start_tx,
 819	.send_xchar	= sunsab_send_xchar,
 820	.stop_rx	= sunsab_stop_rx,
 
 821	.break_ctl	= sunsab_break_ctl,
 822	.startup	= sunsab_startup,
 823	.shutdown	= sunsab_shutdown,
 824	.set_termios	= sunsab_set_termios,
 825	.type		= sunsab_type,
 826	.release_port	= sunsab_release_port,
 827	.request_port	= sunsab_request_port,
 828	.config_port	= sunsab_config_port,
 829	.verify_port	= sunsab_verify_port,
 830};
 831
 832static struct uart_driver sunsab_reg = {
 833	.owner			= THIS_MODULE,
 834	.driver_name		= "sunsab",
 835	.dev_name		= "ttyS",
 836	.major			= TTY_MAJOR,
 837};
 838
 839static struct uart_sunsab_port *sunsab_ports;
 840
 841#ifdef CONFIG_SERIAL_SUNSAB_CONSOLE
 842
 843static void sunsab_console_putchar(struct uart_port *port, unsigned char c)
 844{
 845	struct uart_sunsab_port *up =
 846		container_of(port, struct uart_sunsab_port, port);
 847
 848	sunsab_tec_wait(up);
 849	writeb(c, &up->regs->w.tic);
 850}
 851
 852static void sunsab_console_write(struct console *con, const char *s, unsigned n)
 853{
 854	struct uart_sunsab_port *up = &sunsab_ports[con->index];
 855	unsigned long flags;
 856	int locked = 1;
 857
 858	if (up->port.sysrq || oops_in_progress)
 859		locked = spin_trylock_irqsave(&up->port.lock, flags);
 860	else
 861		spin_lock_irqsave(&up->port.lock, flags);
 
 
 
 862
 863	uart_console_write(&up->port, s, n, sunsab_console_putchar);
 864	sunsab_tec_wait(up);
 865
 866	if (locked)
 867		spin_unlock_irqrestore(&up->port.lock, flags);
 
 868}
 869
 870static int sunsab_console_setup(struct console *con, char *options)
 871{
 872	struct uart_sunsab_port *up = &sunsab_ports[con->index];
 873	unsigned long flags;
 874	unsigned int baud, quot;
 875
 876	/*
 877	 * The console framework calls us for each and every port
 878	 * registered. Defer the console setup until the requested
 879	 * port has been properly discovered. A bit of a hack,
 880	 * though...
 881	 */
 882	if (up->port.type != PORT_SUNSAB)
 883		return -EINVAL;
 884
 885	printk("Console: ttyS%d (SAB82532)\n",
 886	       (sunsab_reg.minor - 64) + con->index);
 887
 888	sunserial_console_termios(con, up->port.dev->of_node);
 889
 890	switch (con->cflag & CBAUD) {
 891	case B150: baud = 150; break;
 892	case B300: baud = 300; break;
 893	case B600: baud = 600; break;
 894	case B1200: baud = 1200; break;
 895	case B2400: baud = 2400; break;
 896	case B4800: baud = 4800; break;
 897	default: case B9600: baud = 9600; break;
 898	case B19200: baud = 19200; break;
 899	case B38400: baud = 38400; break;
 900	case B57600: baud = 57600; break;
 901	case B115200: baud = 115200; break;
 902	case B230400: baud = 230400; break;
 903	case B460800: baud = 460800; break;
 904	}
 905
 906	/*
 907	 * Temporary fix.
 908	 */
 909	spin_lock_init(&up->port.lock);
 910
 911	/*
 912	 * Initialize the hardware
 913	 */
 914	sunsab_startup(&up->port);
 915
 916	spin_lock_irqsave(&up->port.lock, flags);
 917
 918	/*
 919	 * Finally, enable interrupts
 920	 */
 921	up->interrupt_mask0 = SAB82532_IMR0_PERR | SAB82532_IMR0_FERR |
 922				SAB82532_IMR0_PLLA | SAB82532_IMR0_CDSC;
 923	writeb(up->interrupt_mask0, &up->regs->w.imr0);
 924	up->interrupt_mask1 = SAB82532_IMR1_BRKT | SAB82532_IMR1_ALLS |
 925				SAB82532_IMR1_XOFF | SAB82532_IMR1_TIN |
 926				SAB82532_IMR1_CSC | SAB82532_IMR1_XON |
 927				SAB82532_IMR1_XPR;
 928	writeb(up->interrupt_mask1, &up->regs->w.imr1);
 929
 930	quot = uart_get_divisor(&up->port, baud);
 931	sunsab_convert_to_sab(up, con->cflag, 0, baud, quot);
 932	sunsab_set_mctrl(&up->port, TIOCM_DTR | TIOCM_RTS);
 933
 934	spin_unlock_irqrestore(&up->port.lock, flags);
 935	
 936	return 0;
 937}
 938
 939static struct console sunsab_console = {
 940	.name	=	"ttyS",
 941	.write	=	sunsab_console_write,
 942	.device	=	uart_console_device,
 943	.setup	=	sunsab_console_setup,
 944	.flags	=	CON_PRINTBUFFER,
 945	.index	=	-1,
 946	.data	=	&sunsab_reg,
 947};
 948
 949static inline struct console *SUNSAB_CONSOLE(void)
 950{
 951	return &sunsab_console;
 952}
 953#else
 954#define SUNSAB_CONSOLE()	(NULL)
 955#define sunsab_console_init()	do { } while (0)
 956#endif
 957
 958static int sunsab_init_one(struct uart_sunsab_port *up,
 959				     struct platform_device *op,
 960				     unsigned long offset,
 961				     int line)
 962{
 963	up->port.line = line;
 964	up->port.dev = &op->dev;
 965
 966	up->port.mapbase = op->resource[0].start + offset;
 967	up->port.membase = of_ioremap(&op->resource[0], offset,
 968				      sizeof(union sab82532_async_regs),
 969				      "sab");
 970	if (!up->port.membase)
 971		return -ENOMEM;
 972	up->regs = (union sab82532_async_regs __iomem *) up->port.membase;
 973
 974	up->port.irq = op->archdata.irqs[0];
 975
 976	up->port.fifosize = SAB82532_XMIT_FIFO_SIZE;
 977	up->port.iotype = UPIO_MEM;
 978	up->port.has_sysrq = IS_ENABLED(CONFIG_SERIAL_SUNSAB_CONSOLE);
 979
 980	writeb(SAB82532_IPC_IC_ACT_LOW, &up->regs->w.ipc);
 981
 982	up->port.ops = &sunsab_pops;
 983	up->port.type = PORT_SUNSAB;
 984	up->port.uartclk = SAB_BASE_BAUD;
 985
 986	up->type = readb(&up->regs->r.vstr) & 0x0f;
 987	writeb(~((1 << 1) | (1 << 2) | (1 << 4)), &up->regs->w.pcr);
 988	writeb(0xff, &up->regs->w.pim);
 989	if ((up->port.line & 0x1) == 0) {
 990		up->pvr_dsr_bit = (1 << 0);
 991		up->pvr_dtr_bit = (1 << 1);
 992		up->gis_shift = 2;
 993	} else {
 994		up->pvr_dsr_bit = (1 << 3);
 995		up->pvr_dtr_bit = (1 << 2);
 996		up->gis_shift = 0;
 997	}
 998	up->cached_pvr = (1 << 1) | (1 << 2) | (1 << 4);
 999	writeb(up->cached_pvr, &up->regs->w.pvr);
1000	up->cached_mode = readb(&up->regs->rw.mode);
1001	up->cached_mode |= SAB82532_MODE_FRTS;
1002	writeb(up->cached_mode, &up->regs->rw.mode);
1003	up->cached_mode |= SAB82532_MODE_RTS;
1004	writeb(up->cached_mode, &up->regs->rw.mode);
1005
1006	up->tec_timeout = SAB82532_MAX_TEC_TIMEOUT;
1007	up->cec_timeout = SAB82532_MAX_CEC_TIMEOUT;
1008
1009	return 0;
1010}
1011
1012static int sab_probe(struct platform_device *op)
1013{
1014	static int inst;
1015	struct uart_sunsab_port *up;
1016	int err;
1017
1018	up = &sunsab_ports[inst * 2];
1019
1020	err = sunsab_init_one(&up[0], op,
1021			      0,
1022			      (inst * 2) + 0);
1023	if (err)
1024		goto out;
1025
1026	err = sunsab_init_one(&up[1], op,
1027			      sizeof(union sab82532_async_regs),
1028			      (inst * 2) + 1);
1029	if (err)
1030		goto out1;
1031
1032	sunserial_console_match(SUNSAB_CONSOLE(), op->dev.of_node,
1033				&sunsab_reg, up[0].port.line,
1034				false);
1035
1036	sunserial_console_match(SUNSAB_CONSOLE(), op->dev.of_node,
1037				&sunsab_reg, up[1].port.line,
1038				false);
1039
1040	err = uart_add_one_port(&sunsab_reg, &up[0].port);
1041	if (err)
1042		goto out2;
1043
1044	err = uart_add_one_port(&sunsab_reg, &up[1].port);
1045	if (err)
1046		goto out3;
1047
1048	platform_set_drvdata(op, &up[0]);
1049
1050	inst++;
1051
1052	return 0;
1053
1054out3:
1055	uart_remove_one_port(&sunsab_reg, &up[0].port);
1056out2:
1057	of_iounmap(&op->resource[0],
1058		   up[1].port.membase,
1059		   sizeof(union sab82532_async_regs));
1060out1:
1061	of_iounmap(&op->resource[0],
1062		   up[0].port.membase,
1063		   sizeof(union sab82532_async_regs));
1064out:
1065	return err;
1066}
1067
1068static int sab_remove(struct platform_device *op)
1069{
1070	struct uart_sunsab_port *up = platform_get_drvdata(op);
1071
1072	uart_remove_one_port(&sunsab_reg, &up[1].port);
1073	uart_remove_one_port(&sunsab_reg, &up[0].port);
1074	of_iounmap(&op->resource[0],
1075		   up[1].port.membase,
1076		   sizeof(union sab82532_async_regs));
1077	of_iounmap(&op->resource[0],
1078		   up[0].port.membase,
1079		   sizeof(union sab82532_async_regs));
1080
 
 
1081	return 0;
1082}
1083
1084static const struct of_device_id sab_match[] = {
1085	{
1086		.name = "se",
1087	},
1088	{
1089		.name = "serial",
1090		.compatible = "sab82532",
1091	},
1092	{},
1093};
1094MODULE_DEVICE_TABLE(of, sab_match);
1095
1096static struct platform_driver sab_driver = {
1097	.driver = {
1098		.name = "sab",
 
1099		.of_match_table = sab_match,
1100	},
1101	.probe		= sab_probe,
1102	.remove		= sab_remove,
1103};
1104
1105static int __init sunsab_init(void)
1106{
1107	struct device_node *dp;
1108	int err;
1109	int num_channels = 0;
1110
1111	for_each_node_by_name(dp, "se")
1112		num_channels += 2;
1113	for_each_node_by_name(dp, "serial") {
1114		if (of_device_is_compatible(dp, "sab82532"))
1115			num_channels += 2;
1116	}
1117
1118	if (num_channels) {
1119		sunsab_ports = kcalloc(num_channels,
1120				       sizeof(struct uart_sunsab_port),
1121				       GFP_KERNEL);
1122		if (!sunsab_ports)
1123			return -ENOMEM;
1124
1125		err = sunserial_register_minors(&sunsab_reg, num_channels);
1126		if (err) {
1127			kfree(sunsab_ports);
1128			sunsab_ports = NULL;
1129
1130			return err;
1131		}
1132	}
1133
1134	err = platform_driver_register(&sab_driver);
1135	if (err) {
1136		kfree(sunsab_ports);
1137		sunsab_ports = NULL;
1138	}
1139
1140	return err;
1141}
1142
1143static void __exit sunsab_exit(void)
1144{
1145	platform_driver_unregister(&sab_driver);
1146	if (sunsab_reg.nr) {
1147		sunserial_unregister_minors(&sunsab_reg, sunsab_reg.nr);
1148	}
1149
1150	kfree(sunsab_ports);
1151	sunsab_ports = NULL;
1152}
1153
1154module_init(sunsab_init);
1155module_exit(sunsab_exit);
1156
1157MODULE_AUTHOR("Eddie C. Dost and David S. Miller");
1158MODULE_DESCRIPTION("Sun SAB82532 serial port driver");
1159MODULE_LICENSE("GPL");
v3.5.6
 
   1/* sunsab.c: ASYNC Driver for the SIEMENS SAB82532 DUSCC.
   2 *
   3 * Copyright (C) 1997  Eddie C. Dost  (ecd@skynet.be)
   4 * Copyright (C) 2002, 2006  David S. Miller (davem@davemloft.net)
   5 *
   6 * Rewrote buffer handling to use CIRC(Circular Buffer) macros.
   7 *   Maxim Krasnyanskiy <maxk@qualcomm.com>
   8 *
   9 * Fixed to use tty_get_baud_rate, and to allow for arbitrary baud
  10 * rates to be programmed into the UART.  Also eliminated a lot of
  11 * duplicated code in the console setup.
  12 *   Theodore Ts'o <tytso@mit.edu>, 2001-Oct-12
  13 *
  14 * Ported to new 2.5.x UART layer.
  15 *   David S. Miller <davem@davemloft.net>
  16 */
  17
  18#include <linux/module.h>
  19#include <linux/kernel.h>
  20#include <linux/errno.h>
  21#include <linux/tty.h>
  22#include <linux/tty_flip.h>
  23#include <linux/major.h>
  24#include <linux/string.h>
  25#include <linux/ptrace.h>
  26#include <linux/ioport.h>
  27#include <linux/circ_buf.h>
  28#include <linux/serial.h>
  29#include <linux/sysrq.h>
  30#include <linux/console.h>
  31#include <linux/spinlock.h>
  32#include <linux/slab.h>
  33#include <linux/delay.h>
  34#include <linux/init.h>
  35#include <linux/of_device.h>
  36
  37#include <asm/io.h>
  38#include <asm/irq.h>
  39#include <asm/prom.h>
  40#include <asm/setup.h>
  41
  42#if defined(CONFIG_SERIAL_SUNSAB_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
  43#define SUPPORT_SYSRQ
  44#endif
  45
  46#include <linux/serial_core.h>
  47#include <linux/sunserialcore.h>
  48
  49#include "sunsab.h"
  50
  51struct uart_sunsab_port {
  52	struct uart_port		port;		/* Generic UART port	*/
  53	union sab82532_async_regs	__iomem *regs;	/* Chip registers	*/
  54	unsigned long			irqflags;	/* IRQ state flags	*/
  55	int				dsr;		/* Current DSR state	*/
  56	unsigned int			cec_timeout;	/* Chip poll timeout... */
  57	unsigned int			tec_timeout;	/* likewise		*/
  58	unsigned char			interrupt_mask0;/* ISR0 masking		*/
  59	unsigned char			interrupt_mask1;/* ISR1 masking		*/
  60	unsigned char			pvr_dtr_bit;	/* Which PVR bit is DTR */
  61	unsigned char			pvr_dsr_bit;	/* Which PVR bit is DSR */
  62	unsigned int			gis_shift;
  63	int				type;		/* SAB82532 version	*/
  64
  65	/* Setting configuration bits while the transmitter is active
  66	 * can cause garbage characters to get emitted by the chip.
  67	 * Therefore, we cache such writes here and do the real register
  68	 * write the next time the transmitter becomes idle.
  69	 */
  70	unsigned int			cached_ebrg;
  71	unsigned char			cached_mode;
  72	unsigned char			cached_pvr;
  73	unsigned char			cached_dafo;
  74};
  75
  76/*
  77 * This assumes you have a 29.4912 MHz clock for your UART.
  78 */
  79#define SAB_BASE_BAUD ( 29491200 / 16 )
  80
  81static char *sab82532_version[16] = {
  82	"V1.0", "V2.0", "V3.2", "V(0x03)",
  83	"V(0x04)", "V(0x05)", "V(0x06)", "V(0x07)",
  84	"V(0x08)", "V(0x09)", "V(0x0a)", "V(0x0b)",
  85	"V(0x0c)", "V(0x0d)", "V(0x0e)", "V(0x0f)"
  86};
  87
  88#define SAB82532_MAX_TEC_TIMEOUT 200000	/* 1 character time (at 50 baud) */
  89#define SAB82532_MAX_CEC_TIMEOUT  50000	/* 2.5 TX CLKs (at 50 baud) */
  90
  91#define SAB82532_RECV_FIFO_SIZE	32      /* Standard async fifo sizes */
  92#define SAB82532_XMIT_FIFO_SIZE	32
  93
  94static __inline__ void sunsab_tec_wait(struct uart_sunsab_port *up)
  95{
  96	int timeout = up->tec_timeout;
  97
  98	while ((readb(&up->regs->r.star) & SAB82532_STAR_TEC) && --timeout)
  99		udelay(1);
 100}
 101
 102static __inline__ void sunsab_cec_wait(struct uart_sunsab_port *up)
 103{
 104	int timeout = up->cec_timeout;
 105
 106	while ((readb(&up->regs->r.star) & SAB82532_STAR_CEC) && --timeout)
 107		udelay(1);
 108}
 109
 110static struct tty_struct *
 111receive_chars(struct uart_sunsab_port *up,
 112	      union sab82532_irq_status *stat)
 113{
 114	struct tty_struct *tty = NULL;
 115	unsigned char buf[32];
 116	int saw_console_brk = 0;
 117	int free_fifo = 0;
 118	int count = 0;
 119	int i;
 120
 121	if (up->port.state != NULL)		/* Unopened serial console */
 122		tty = up->port.state->port.tty;
 123
 124	/* Read number of BYTES (Character + Status) available. */
 125	if (stat->sreg.isr0 & SAB82532_ISR0_RPF) {
 126		count = SAB82532_RECV_FIFO_SIZE;
 127		free_fifo++;
 128	}
 129
 130	if (stat->sreg.isr0 & SAB82532_ISR0_TCD) {
 131		count = readb(&up->regs->r.rbcl) & (SAB82532_RECV_FIFO_SIZE - 1);
 132		free_fifo++;
 133	}
 134
 135	/* Issue a FIFO read command in case we where idle. */
 136	if (stat->sreg.isr0 & SAB82532_ISR0_TIME) {
 137		sunsab_cec_wait(up);
 138		writeb(SAB82532_CMDR_RFRD, &up->regs->w.cmdr);
 139		return tty;
 140	}
 141
 142	if (stat->sreg.isr0 & SAB82532_ISR0_RFO)
 143		free_fifo++;
 144
 145	/* Read the FIFO. */
 146	for (i = 0; i < count; i++)
 147		buf[i] = readb(&up->regs->r.rfifo[i]);
 148
 149	/* Issue Receive Message Complete command. */
 150	if (free_fifo) {
 151		sunsab_cec_wait(up);
 152		writeb(SAB82532_CMDR_RMC, &up->regs->w.cmdr);
 153	}
 154
 155	/* Count may be zero for BRK, so we check for it here */
 156	if ((stat->sreg.isr1 & SAB82532_ISR1_BRK) &&
 157	    (up->port.line == up->port.cons->index))
 158		saw_console_brk = 1;
 159
 
 
 
 
 
 
 
 
 
 160	for (i = 0; i < count; i++) {
 161		unsigned char ch = buf[i], flag;
 162
 163		if (tty == NULL) {
 164			uart_handle_sysrq_char(&up->port, ch);
 165			continue;
 166		}
 167
 168		flag = TTY_NORMAL;
 169		up->port.icount.rx++;
 170
 171		if (unlikely(stat->sreg.isr0 & (SAB82532_ISR0_PERR |
 172						SAB82532_ISR0_FERR |
 173						SAB82532_ISR0_RFO)) ||
 174		    unlikely(stat->sreg.isr1 & SAB82532_ISR1_BRK)) {
 175			/*
 176			 * For statistics only
 177			 */
 178			if (stat->sreg.isr1 & SAB82532_ISR1_BRK) {
 179				stat->sreg.isr0 &= ~(SAB82532_ISR0_PERR |
 180						     SAB82532_ISR0_FERR);
 181				up->port.icount.brk++;
 182				/*
 183				 * We do the SysRQ and SAK checking
 184				 * here because otherwise the break
 185				 * may get masked by ignore_status_mask
 186				 * or read_status_mask.
 187				 */
 188				if (uart_handle_break(&up->port))
 189					continue;
 190			} else if (stat->sreg.isr0 & SAB82532_ISR0_PERR)
 191				up->port.icount.parity++;
 192			else if (stat->sreg.isr0 & SAB82532_ISR0_FERR)
 193				up->port.icount.frame++;
 194			if (stat->sreg.isr0 & SAB82532_ISR0_RFO)
 195				up->port.icount.overrun++;
 196
 197			/*
 198			 * Mask off conditions which should be ingored.
 199			 */
 200			stat->sreg.isr0 &= (up->port.read_status_mask & 0xff);
 201			stat->sreg.isr1 &= ((up->port.read_status_mask >> 8) & 0xff);
 202
 203			if (stat->sreg.isr1 & SAB82532_ISR1_BRK) {
 204				flag = TTY_BREAK;
 205			} else if (stat->sreg.isr0 & SAB82532_ISR0_PERR)
 206				flag = TTY_PARITY;
 207			else if (stat->sreg.isr0 & SAB82532_ISR0_FERR)
 208				flag = TTY_FRAME;
 209		}
 210
 211		if (uart_handle_sysrq_char(&up->port, ch))
 212			continue;
 213
 214		if ((stat->sreg.isr0 & (up->port.ignore_status_mask & 0xff)) == 0 &&
 215		    (stat->sreg.isr1 & ((up->port.ignore_status_mask >> 8) & 0xff)) == 0)
 216			tty_insert_flip_char(tty, ch, flag);
 217		if (stat->sreg.isr0 & SAB82532_ISR0_RFO)
 218			tty_insert_flip_char(tty, 0, TTY_OVERRUN);
 219	}
 220
 221	if (saw_console_brk)
 222		sun_do_break();
 223
 224	return tty;
 225}
 226
 227static void sunsab_stop_tx(struct uart_port *);
 228static void sunsab_tx_idle(struct uart_sunsab_port *);
 229
 230static void transmit_chars(struct uart_sunsab_port *up,
 231			   union sab82532_irq_status *stat)
 232{
 233	struct circ_buf *xmit = &up->port.state->xmit;
 234	int i;
 235
 236	if (stat->sreg.isr1 & SAB82532_ISR1_ALLS) {
 237		up->interrupt_mask1 |= SAB82532_IMR1_ALLS;
 238		writeb(up->interrupt_mask1, &up->regs->w.imr1);
 239		set_bit(SAB82532_ALLS, &up->irqflags);
 240	}
 241
 242#if 0 /* bde@nwlink.com says this check causes problems */
 243	if (!(stat->sreg.isr1 & SAB82532_ISR1_XPR))
 244		return;
 245#endif
 246
 247	if (!(readb(&up->regs->r.star) & SAB82532_STAR_XFW))
 248		return;
 249
 250	set_bit(SAB82532_XPR, &up->irqflags);
 251	sunsab_tx_idle(up);
 252
 253	if (uart_circ_empty(xmit) || uart_tx_stopped(&up->port)) {
 254		up->interrupt_mask1 |= SAB82532_IMR1_XPR;
 255		writeb(up->interrupt_mask1, &up->regs->w.imr1);
 256		return;
 257	}
 258
 259	up->interrupt_mask1 &= ~(SAB82532_IMR1_ALLS|SAB82532_IMR1_XPR);
 260	writeb(up->interrupt_mask1, &up->regs->w.imr1);
 261	clear_bit(SAB82532_ALLS, &up->irqflags);
 262
 263	/* Stuff 32 bytes into Transmit FIFO. */
 264	clear_bit(SAB82532_XPR, &up->irqflags);
 265	for (i = 0; i < up->port.fifosize; i++) {
 266		writeb(xmit->buf[xmit->tail],
 267		       &up->regs->w.xfifo[i]);
 268		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
 269		up->port.icount.tx++;
 270		if (uart_circ_empty(xmit))
 271			break;
 272	}
 273
 274	/* Issue a Transmit Frame command. */
 275	sunsab_cec_wait(up);
 276	writeb(SAB82532_CMDR_XF, &up->regs->w.cmdr);
 277
 278	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
 279		uart_write_wakeup(&up->port);
 280
 281	if (uart_circ_empty(xmit))
 282		sunsab_stop_tx(&up->port);
 283}
 284
 285static void check_status(struct uart_sunsab_port *up,
 286			 union sab82532_irq_status *stat)
 287{
 288	if (stat->sreg.isr0 & SAB82532_ISR0_CDSC)
 289		uart_handle_dcd_change(&up->port,
 290				       !(readb(&up->regs->r.vstr) & SAB82532_VSTR_CD));
 291
 292	if (stat->sreg.isr1 & SAB82532_ISR1_CSC)
 293		uart_handle_cts_change(&up->port,
 294				       (readb(&up->regs->r.star) & SAB82532_STAR_CTS));
 295
 296	if ((readb(&up->regs->r.pvr) & up->pvr_dsr_bit) ^ up->dsr) {
 297		up->dsr = (readb(&up->regs->r.pvr) & up->pvr_dsr_bit) ? 0 : 1;
 298		up->port.icount.dsr++;
 299	}
 300
 301	wake_up_interruptible(&up->port.state->port.delta_msr_wait);
 302}
 303
 304static irqreturn_t sunsab_interrupt(int irq, void *dev_id)
 305{
 306	struct uart_sunsab_port *up = dev_id;
 307	struct tty_struct *tty;
 308	union sab82532_irq_status status;
 309	unsigned long flags;
 310	unsigned char gis;
 311
 312	spin_lock_irqsave(&up->port.lock, flags);
 313
 314	status.stat = 0;
 315	gis = readb(&up->regs->r.gis) >> up->gis_shift;
 316	if (gis & 1)
 317		status.sreg.isr0 = readb(&up->regs->r.isr0);
 318	if (gis & 2)
 319		status.sreg.isr1 = readb(&up->regs->r.isr1);
 320
 321	tty = NULL;
 322	if (status.stat) {
 323		if ((status.sreg.isr0 & (SAB82532_ISR0_TCD | SAB82532_ISR0_TIME |
 324					 SAB82532_ISR0_RFO | SAB82532_ISR0_RPF)) ||
 325		    (status.sreg.isr1 & SAB82532_ISR1_BRK))
 326			tty = receive_chars(up, &status);
 327		if ((status.sreg.isr0 & SAB82532_ISR0_CDSC) ||
 328		    (status.sreg.isr1 & SAB82532_ISR1_CSC))
 329			check_status(up, &status);
 330		if (status.sreg.isr1 & (SAB82532_ISR1_ALLS | SAB82532_ISR1_XPR))
 331			transmit_chars(up, &status);
 332	}
 333
 334	spin_unlock_irqrestore(&up->port.lock, flags);
 335
 336	if (tty)
 337		tty_flip_buffer_push(tty);
 338
 339	return IRQ_HANDLED;
 340}
 341
 342/* port->lock is not held.  */
 343static unsigned int sunsab_tx_empty(struct uart_port *port)
 344{
 345	struct uart_sunsab_port *up = (struct uart_sunsab_port *) port;
 
 346	int ret;
 347
 348	/* Do not need a lock for a state test like this.  */
 349	if (test_bit(SAB82532_ALLS, &up->irqflags))
 350		ret = TIOCSER_TEMT;
 351	else
 352		ret = 0;
 353
 354	return ret;
 355}
 356
 357/* port->lock held by caller.  */
 358static void sunsab_set_mctrl(struct uart_port *port, unsigned int mctrl)
 359{
 360	struct uart_sunsab_port *up = (struct uart_sunsab_port *) port;
 
 361
 362	if (mctrl & TIOCM_RTS) {
 363		up->cached_mode &= ~SAB82532_MODE_FRTS;
 364		up->cached_mode |= SAB82532_MODE_RTS;
 365	} else {
 366		up->cached_mode |= (SAB82532_MODE_FRTS |
 367				    SAB82532_MODE_RTS);
 368	}
 369	if (mctrl & TIOCM_DTR) {
 370		up->cached_pvr &= ~(up->pvr_dtr_bit);
 371	} else {
 372		up->cached_pvr |= up->pvr_dtr_bit;
 373	}
 374
 375	set_bit(SAB82532_REGS_PENDING, &up->irqflags);
 376	if (test_bit(SAB82532_XPR, &up->irqflags))
 377		sunsab_tx_idle(up);
 378}
 379
 380/* port->lock is held by caller and interrupts are disabled.  */
 381static unsigned int sunsab_get_mctrl(struct uart_port *port)
 382{
 383	struct uart_sunsab_port *up = (struct uart_sunsab_port *) port;
 
 384	unsigned char val;
 385	unsigned int result;
 386
 387	result = 0;
 388
 389	val = readb(&up->regs->r.pvr);
 390	result |= (val & up->pvr_dsr_bit) ? 0 : TIOCM_DSR;
 391
 392	val = readb(&up->regs->r.vstr);
 393	result |= (val & SAB82532_VSTR_CD) ? 0 : TIOCM_CAR;
 394
 395	val = readb(&up->regs->r.star);
 396	result |= (val & SAB82532_STAR_CTS) ? TIOCM_CTS : 0;
 397
 398	return result;
 399}
 400
 401/* port->lock held by caller.  */
 402static void sunsab_stop_tx(struct uart_port *port)
 403{
 404	struct uart_sunsab_port *up = (struct uart_sunsab_port *) port;
 
 405
 406	up->interrupt_mask1 |= SAB82532_IMR1_XPR;
 407	writeb(up->interrupt_mask1, &up->regs->w.imr1);
 408}
 409
 410/* port->lock held by caller.  */
 411static void sunsab_tx_idle(struct uart_sunsab_port *up)
 412{
 413	if (test_bit(SAB82532_REGS_PENDING, &up->irqflags)) {
 414		u8 tmp;
 415
 416		clear_bit(SAB82532_REGS_PENDING, &up->irqflags);
 417		writeb(up->cached_mode, &up->regs->rw.mode);
 418		writeb(up->cached_pvr, &up->regs->rw.pvr);
 419		writeb(up->cached_dafo, &up->regs->w.dafo);
 420
 421		writeb(up->cached_ebrg & 0xff, &up->regs->w.bgr);
 422		tmp = readb(&up->regs->rw.ccr2);
 423		tmp &= ~0xc0;
 424		tmp |= (up->cached_ebrg >> 2) & 0xc0;
 425		writeb(tmp, &up->regs->rw.ccr2);
 426	}
 427}
 428
 429/* port->lock held by caller.  */
 430static void sunsab_start_tx(struct uart_port *port)
 431{
 432	struct uart_sunsab_port *up = (struct uart_sunsab_port *) port;
 
 433	struct circ_buf *xmit = &up->port.state->xmit;
 434	int i;
 435
 
 
 
 436	up->interrupt_mask1 &= ~(SAB82532_IMR1_ALLS|SAB82532_IMR1_XPR);
 437	writeb(up->interrupt_mask1, &up->regs->w.imr1);
 438	
 439	if (!test_bit(SAB82532_XPR, &up->irqflags))
 440		return;
 441
 442	clear_bit(SAB82532_ALLS, &up->irqflags);
 443	clear_bit(SAB82532_XPR, &up->irqflags);
 444
 445	for (i = 0; i < up->port.fifosize; i++) {
 446		writeb(xmit->buf[xmit->tail],
 447		       &up->regs->w.xfifo[i]);
 448		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
 449		up->port.icount.tx++;
 450		if (uart_circ_empty(xmit))
 451			break;
 452	}
 453
 454	/* Issue a Transmit Frame command.  */
 455	sunsab_cec_wait(up);
 456	writeb(SAB82532_CMDR_XF, &up->regs->w.cmdr);
 457}
 458
 459/* port->lock is not held.  */
 460static void sunsab_send_xchar(struct uart_port *port, char ch)
 461{
 462	struct uart_sunsab_port *up = (struct uart_sunsab_port *) port;
 
 463	unsigned long flags;
 464
 
 
 
 465	spin_lock_irqsave(&up->port.lock, flags);
 466
 467	sunsab_tec_wait(up);
 468	writeb(ch, &up->regs->w.tic);
 469
 470	spin_unlock_irqrestore(&up->port.lock, flags);
 471}
 472
 473/* port->lock held by caller.  */
 474static void sunsab_stop_rx(struct uart_port *port)
 475{
 476	struct uart_sunsab_port *up = (struct uart_sunsab_port *) port;
 
 477
 478	up->interrupt_mask0 |= SAB82532_IMR0_TCD;
 479	writeb(up->interrupt_mask1, &up->regs->w.imr0);
 480}
 481
 482/* port->lock held by caller.  */
 483static void sunsab_enable_ms(struct uart_port *port)
 484{
 485	/* For now we always receive these interrupts.  */
 486}
 487
 488/* port->lock is not held.  */
 489static void sunsab_break_ctl(struct uart_port *port, int break_state)
 490{
 491	struct uart_sunsab_port *up = (struct uart_sunsab_port *) port;
 
 492	unsigned long flags;
 493	unsigned char val;
 494
 495	spin_lock_irqsave(&up->port.lock, flags);
 496
 497	val = up->cached_dafo;
 498	if (break_state)
 499		val |= SAB82532_DAFO_XBRK;
 500	else
 501		val &= ~SAB82532_DAFO_XBRK;
 502	up->cached_dafo = val;
 503
 504	set_bit(SAB82532_REGS_PENDING, &up->irqflags);
 505	if (test_bit(SAB82532_XPR, &up->irqflags))
 506		sunsab_tx_idle(up);
 507
 508	spin_unlock_irqrestore(&up->port.lock, flags);
 509}
 510
 511/* port->lock is not held.  */
 512static int sunsab_startup(struct uart_port *port)
 513{
 514	struct uart_sunsab_port *up = (struct uart_sunsab_port *) port;
 
 515	unsigned long flags;
 516	unsigned char tmp;
 517	int err = request_irq(up->port.irq, sunsab_interrupt,
 518			      IRQF_SHARED, "sab", up);
 519	if (err)
 520		return err;
 521
 522	spin_lock_irqsave(&up->port.lock, flags);
 523
 524	/*
 525	 * Wait for any commands or immediate characters
 526	 */
 527	sunsab_cec_wait(up);
 528	sunsab_tec_wait(up);
 529
 530	/*
 531	 * Clear the FIFO buffers.
 532	 */
 533	writeb(SAB82532_CMDR_RRES, &up->regs->w.cmdr);
 534	sunsab_cec_wait(up);
 535	writeb(SAB82532_CMDR_XRES, &up->regs->w.cmdr);
 536
 537	/*
 538	 * Clear the interrupt registers.
 539	 */
 540	(void) readb(&up->regs->r.isr0);
 541	(void) readb(&up->regs->r.isr1);
 542
 543	/*
 544	 * Now, initialize the UART 
 545	 */
 546	writeb(0, &up->regs->w.ccr0);				/* power-down */
 547	writeb(SAB82532_CCR0_MCE | SAB82532_CCR0_SC_NRZ |
 548	       SAB82532_CCR0_SM_ASYNC, &up->regs->w.ccr0);
 549	writeb(SAB82532_CCR1_ODS | SAB82532_CCR1_BCR | 7, &up->regs->w.ccr1);
 550	writeb(SAB82532_CCR2_BDF | SAB82532_CCR2_SSEL |
 551	       SAB82532_CCR2_TOE, &up->regs->w.ccr2);
 552	writeb(0, &up->regs->w.ccr3);
 553	writeb(SAB82532_CCR4_MCK4 | SAB82532_CCR4_EBRG, &up->regs->w.ccr4);
 554	up->cached_mode = (SAB82532_MODE_RTS | SAB82532_MODE_FCTS |
 555			   SAB82532_MODE_RAC);
 556	writeb(up->cached_mode, &up->regs->w.mode);
 557	writeb(SAB82532_RFC_DPS|SAB82532_RFC_RFTH_32, &up->regs->w.rfc);
 558	
 559	tmp = readb(&up->regs->rw.ccr0);
 560	tmp |= SAB82532_CCR0_PU;	/* power-up */
 561	writeb(tmp, &up->regs->rw.ccr0);
 562
 563	/*
 564	 * Finally, enable interrupts
 565	 */
 566	up->interrupt_mask0 = (SAB82532_IMR0_PERR | SAB82532_IMR0_FERR |
 567			       SAB82532_IMR0_PLLA);
 568	writeb(up->interrupt_mask0, &up->regs->w.imr0);
 569	up->interrupt_mask1 = (SAB82532_IMR1_BRKT | SAB82532_IMR1_ALLS |
 570			       SAB82532_IMR1_XOFF | SAB82532_IMR1_TIN |
 571			       SAB82532_IMR1_CSC | SAB82532_IMR1_XON |
 572			       SAB82532_IMR1_XPR);
 573	writeb(up->interrupt_mask1, &up->regs->w.imr1);
 574	set_bit(SAB82532_ALLS, &up->irqflags);
 575	set_bit(SAB82532_XPR, &up->irqflags);
 576
 577	spin_unlock_irqrestore(&up->port.lock, flags);
 578
 579	return 0;
 580}
 581
 582/* port->lock is not held.  */
 583static void sunsab_shutdown(struct uart_port *port)
 584{
 585	struct uart_sunsab_port *up = (struct uart_sunsab_port *) port;
 
 586	unsigned long flags;
 587
 588	spin_lock_irqsave(&up->port.lock, flags);
 589
 590	/* Disable Interrupts */
 591	up->interrupt_mask0 = 0xff;
 592	writeb(up->interrupt_mask0, &up->regs->w.imr0);
 593	up->interrupt_mask1 = 0xff;
 594	writeb(up->interrupt_mask1, &up->regs->w.imr1);
 595
 596	/* Disable break condition */
 597	up->cached_dafo = readb(&up->regs->rw.dafo);
 598	up->cached_dafo &= ~SAB82532_DAFO_XBRK;
 599	writeb(up->cached_dafo, &up->regs->rw.dafo);
 600
 601	/* Disable Receiver */	
 602	up->cached_mode &= ~SAB82532_MODE_RAC;
 603	writeb(up->cached_mode, &up->regs->rw.mode);
 604
 605	/*
 606	 * XXX FIXME
 607	 *
 608	 * If the chip is powered down here the system hangs/crashes during
 609	 * reboot or shutdown.  This needs to be investigated further,
 610	 * similar behaviour occurs in 2.4 when the driver is configured
 611	 * as a module only.  One hint may be that data is sometimes
 612	 * transmitted at 9600 baud during shutdown (regardless of the
 613	 * speed the chip was configured for when the port was open).
 614	 */
 615#if 0
 616	/* Power Down */	
 617	tmp = readb(&up->regs->rw.ccr0);
 618	tmp &= ~SAB82532_CCR0_PU;
 619	writeb(tmp, &up->regs->rw.ccr0);
 620#endif
 621
 622	spin_unlock_irqrestore(&up->port.lock, flags);
 623	free_irq(up->port.irq, up);
 624}
 625
 626/*
 627 * This is used to figure out the divisor speeds.
 628 *
 629 * The formula is:    Baud = SAB_BASE_BAUD / ((N + 1) * (1 << M)),
 630 *
 631 * with               0 <= N < 64 and 0 <= M < 16
 632 */
 633
 634static void calc_ebrg(int baud, int *n_ret, int *m_ret)
 635{
 636	int	n, m;
 637
 638	if (baud == 0) {
 639		*n_ret = 0;
 640		*m_ret = 0;
 641		return;
 642	}
 643     
 644	/*
 645	 * We scale numbers by 10 so that we get better accuracy
 646	 * without having to use floating point.  Here we increment m
 647	 * until n is within the valid range.
 648	 */
 649	n = (SAB_BASE_BAUD * 10) / baud;
 650	m = 0;
 651	while (n >= 640) {
 652		n = n / 2;
 653		m++;
 654	}
 655	n = (n+5) / 10;
 656	/*
 657	 * We try very hard to avoid speeds with M == 0 since they may
 658	 * not work correctly for XTAL frequences above 10 MHz.
 659	 */
 660	if ((m == 0) && ((n & 1) == 0)) {
 661		n = n / 2;
 662		m++;
 663	}
 664	*n_ret = n - 1;
 665	*m_ret = m;
 666}
 667
 668/* Internal routine, port->lock is held and local interrupts are disabled.  */
 669static void sunsab_convert_to_sab(struct uart_sunsab_port *up, unsigned int cflag,
 670				  unsigned int iflag, unsigned int baud,
 671				  unsigned int quot)
 672{
 673	unsigned char dafo;
 674	int bits, n, m;
 675
 676	/* Byte size and parity */
 677	switch (cflag & CSIZE) {
 678	      case CS5: dafo = SAB82532_DAFO_CHL5; bits = 7; break;
 679	      case CS6: dafo = SAB82532_DAFO_CHL6; bits = 8; break;
 680	      case CS7: dafo = SAB82532_DAFO_CHL7; bits = 9; break;
 681	      case CS8: dafo = SAB82532_DAFO_CHL8; bits = 10; break;
 682	      /* Never happens, but GCC is too dumb to figure it out */
 683	      default:  dafo = SAB82532_DAFO_CHL5; bits = 7; break;
 684	}
 685
 686	if (cflag & CSTOPB) {
 687		dafo |= SAB82532_DAFO_STOP;
 688		bits++;
 689	}
 690
 691	if (cflag & PARENB) {
 692		dafo |= SAB82532_DAFO_PARE;
 693		bits++;
 694	}
 695
 696	if (cflag & PARODD) {
 697		dafo |= SAB82532_DAFO_PAR_ODD;
 698	} else {
 699		dafo |= SAB82532_DAFO_PAR_EVEN;
 700	}
 701	up->cached_dafo = dafo;
 702
 703	calc_ebrg(baud, &n, &m);
 704
 705	up->cached_ebrg = n | (m << 6);
 706
 707	up->tec_timeout = (10 * 1000000) / baud;
 708	up->cec_timeout = up->tec_timeout >> 2;
 709
 710	/* CTS flow control flags */
 711	/* We encode read_status_mask and ignore_status_mask like so:
 712	 *
 713	 * ---------------------
 714	 * | ... | ISR1 | ISR0 |
 715	 * ---------------------
 716	 *  ..    15   8 7    0
 717	 */
 718
 719	up->port.read_status_mask = (SAB82532_ISR0_TCD | SAB82532_ISR0_TIME |
 720				     SAB82532_ISR0_RFO | SAB82532_ISR0_RPF |
 721				     SAB82532_ISR0_CDSC);
 722	up->port.read_status_mask |= (SAB82532_ISR1_CSC |
 723				      SAB82532_ISR1_ALLS |
 724				      SAB82532_ISR1_XPR) << 8;
 725	if (iflag & INPCK)
 726		up->port.read_status_mask |= (SAB82532_ISR0_PERR |
 727					      SAB82532_ISR0_FERR);
 728	if (iflag & (BRKINT | PARMRK))
 729		up->port.read_status_mask |= (SAB82532_ISR1_BRK << 8);
 730
 731	/*
 732	 * Characteres to ignore
 733	 */
 734	up->port.ignore_status_mask = 0;
 735	if (iflag & IGNPAR)
 736		up->port.ignore_status_mask |= (SAB82532_ISR0_PERR |
 737						SAB82532_ISR0_FERR);
 738	if (iflag & IGNBRK) {
 739		up->port.ignore_status_mask |= (SAB82532_ISR1_BRK << 8);
 740		/*
 741		 * If we're ignoring parity and break indicators,
 742		 * ignore overruns too (for real raw support).
 743		 */
 744		if (iflag & IGNPAR)
 745			up->port.ignore_status_mask |= SAB82532_ISR0_RFO;
 746	}
 747
 748	/*
 749	 * ignore all characters if CREAD is not set
 750	 */
 751	if ((cflag & CREAD) == 0)
 752		up->port.ignore_status_mask |= (SAB82532_ISR0_RPF |
 753						SAB82532_ISR0_TCD);
 754
 755	uart_update_timeout(&up->port, cflag,
 756			    (up->port.uartclk / (16 * quot)));
 757
 758	/* Now schedule a register update when the chip's
 759	 * transmitter is idle.
 760	 */
 761	up->cached_mode |= SAB82532_MODE_RAC;
 762	set_bit(SAB82532_REGS_PENDING, &up->irqflags);
 763	if (test_bit(SAB82532_XPR, &up->irqflags))
 764		sunsab_tx_idle(up);
 765}
 766
 767/* port->lock is not held.  */
 768static void sunsab_set_termios(struct uart_port *port, struct ktermios *termios,
 769			       struct ktermios *old)
 770{
 771	struct uart_sunsab_port *up = (struct uart_sunsab_port *) port;
 
 772	unsigned long flags;
 773	unsigned int baud = uart_get_baud_rate(port, termios, old, 0, 4000000);
 774	unsigned int quot = uart_get_divisor(port, baud);
 775
 776	spin_lock_irqsave(&up->port.lock, flags);
 777	sunsab_convert_to_sab(up, termios->c_cflag, termios->c_iflag, baud, quot);
 778	spin_unlock_irqrestore(&up->port.lock, flags);
 779}
 780
 781static const char *sunsab_type(struct uart_port *port)
 782{
 783	struct uart_sunsab_port *up = (void *)port;
 784	static char buf[36];
 785	
 786	sprintf(buf, "SAB82532 %s", sab82532_version[up->type]);
 787	return buf;
 788}
 789
 790static void sunsab_release_port(struct uart_port *port)
 791{
 792}
 793
 794static int sunsab_request_port(struct uart_port *port)
 795{
 796	return 0;
 797}
 798
 799static void sunsab_config_port(struct uart_port *port, int flags)
 800{
 801}
 802
 803static int sunsab_verify_port(struct uart_port *port, struct serial_struct *ser)
 804{
 805	return -EINVAL;
 806}
 807
 808static struct uart_ops sunsab_pops = {
 809	.tx_empty	= sunsab_tx_empty,
 810	.set_mctrl	= sunsab_set_mctrl,
 811	.get_mctrl	= sunsab_get_mctrl,
 812	.stop_tx	= sunsab_stop_tx,
 813	.start_tx	= sunsab_start_tx,
 814	.send_xchar	= sunsab_send_xchar,
 815	.stop_rx	= sunsab_stop_rx,
 816	.enable_ms	= sunsab_enable_ms,
 817	.break_ctl	= sunsab_break_ctl,
 818	.startup	= sunsab_startup,
 819	.shutdown	= sunsab_shutdown,
 820	.set_termios	= sunsab_set_termios,
 821	.type		= sunsab_type,
 822	.release_port	= sunsab_release_port,
 823	.request_port	= sunsab_request_port,
 824	.config_port	= sunsab_config_port,
 825	.verify_port	= sunsab_verify_port,
 826};
 827
 828static struct uart_driver sunsab_reg = {
 829	.owner			= THIS_MODULE,
 830	.driver_name		= "sunsab",
 831	.dev_name		= "ttyS",
 832	.major			= TTY_MAJOR,
 833};
 834
 835static struct uart_sunsab_port *sunsab_ports;
 836
 837#ifdef CONFIG_SERIAL_SUNSAB_CONSOLE
 838
 839static void sunsab_console_putchar(struct uart_port *port, int c)
 840{
 841	struct uart_sunsab_port *up = (struct uart_sunsab_port *)port;
 
 842
 843	sunsab_tec_wait(up);
 844	writeb(c, &up->regs->w.tic);
 845}
 846
 847static void sunsab_console_write(struct console *con, const char *s, unsigned n)
 848{
 849	struct uart_sunsab_port *up = &sunsab_ports[con->index];
 850	unsigned long flags;
 851	int locked = 1;
 852
 853	local_irq_save(flags);
 854	if (up->port.sysrq) {
 855		locked = 0;
 856	} else if (oops_in_progress) {
 857		locked = spin_trylock(&up->port.lock);
 858	} else
 859		spin_lock(&up->port.lock);
 860
 861	uart_console_write(&up->port, s, n, sunsab_console_putchar);
 862	sunsab_tec_wait(up);
 863
 864	if (locked)
 865		spin_unlock(&up->port.lock);
 866	local_irq_restore(flags);
 867}
 868
 869static int sunsab_console_setup(struct console *con, char *options)
 870{
 871	struct uart_sunsab_port *up = &sunsab_ports[con->index];
 872	unsigned long flags;
 873	unsigned int baud, quot;
 874
 875	/*
 876	 * The console framework calls us for each and every port
 877	 * registered. Defer the console setup until the requested
 878	 * port has been properly discovered. A bit of a hack,
 879	 * though...
 880	 */
 881	if (up->port.type != PORT_SUNSAB)
 882		return -1;
 883
 884	printk("Console: ttyS%d (SAB82532)\n",
 885	       (sunsab_reg.minor - 64) + con->index);
 886
 887	sunserial_console_termios(con, up->port.dev->of_node);
 888
 889	switch (con->cflag & CBAUD) {
 890	case B150: baud = 150; break;
 891	case B300: baud = 300; break;
 892	case B600: baud = 600; break;
 893	case B1200: baud = 1200; break;
 894	case B2400: baud = 2400; break;
 895	case B4800: baud = 4800; break;
 896	default: case B9600: baud = 9600; break;
 897	case B19200: baud = 19200; break;
 898	case B38400: baud = 38400; break;
 899	case B57600: baud = 57600; break;
 900	case B115200: baud = 115200; break;
 901	case B230400: baud = 230400; break;
 902	case B460800: baud = 460800; break;
 903	};
 904
 905	/*
 906	 * Temporary fix.
 907	 */
 908	spin_lock_init(&up->port.lock);
 909
 910	/*
 911	 * Initialize the hardware
 912	 */
 913	sunsab_startup(&up->port);
 914
 915	spin_lock_irqsave(&up->port.lock, flags);
 916
 917	/*
 918	 * Finally, enable interrupts
 919	 */
 920	up->interrupt_mask0 = SAB82532_IMR0_PERR | SAB82532_IMR0_FERR |
 921				SAB82532_IMR0_PLLA | SAB82532_IMR0_CDSC;
 922	writeb(up->interrupt_mask0, &up->regs->w.imr0);
 923	up->interrupt_mask1 = SAB82532_IMR1_BRKT | SAB82532_IMR1_ALLS |
 924				SAB82532_IMR1_XOFF | SAB82532_IMR1_TIN |
 925				SAB82532_IMR1_CSC | SAB82532_IMR1_XON |
 926				SAB82532_IMR1_XPR;
 927	writeb(up->interrupt_mask1, &up->regs->w.imr1);
 928
 929	quot = uart_get_divisor(&up->port, baud);
 930	sunsab_convert_to_sab(up, con->cflag, 0, baud, quot);
 931	sunsab_set_mctrl(&up->port, TIOCM_DTR | TIOCM_RTS);
 932
 933	spin_unlock_irqrestore(&up->port.lock, flags);
 934	
 935	return 0;
 936}
 937
 938static struct console sunsab_console = {
 939	.name	=	"ttyS",
 940	.write	=	sunsab_console_write,
 941	.device	=	uart_console_device,
 942	.setup	=	sunsab_console_setup,
 943	.flags	=	CON_PRINTBUFFER,
 944	.index	=	-1,
 945	.data	=	&sunsab_reg,
 946};
 947
 948static inline struct console *SUNSAB_CONSOLE(void)
 949{
 950	return &sunsab_console;
 951}
 952#else
 953#define SUNSAB_CONSOLE()	(NULL)
 954#define sunsab_console_init()	do { } while (0)
 955#endif
 956
 957static int __devinit sunsab_init_one(struct uart_sunsab_port *up,
 958				     struct platform_device *op,
 959				     unsigned long offset,
 960				     int line)
 961{
 962	up->port.line = line;
 963	up->port.dev = &op->dev;
 964
 965	up->port.mapbase = op->resource[0].start + offset;
 966	up->port.membase = of_ioremap(&op->resource[0], offset,
 967				      sizeof(union sab82532_async_regs),
 968				      "sab");
 969	if (!up->port.membase)
 970		return -ENOMEM;
 971	up->regs = (union sab82532_async_regs __iomem *) up->port.membase;
 972
 973	up->port.irq = op->archdata.irqs[0];
 974
 975	up->port.fifosize = SAB82532_XMIT_FIFO_SIZE;
 976	up->port.iotype = UPIO_MEM;
 
 977
 978	writeb(SAB82532_IPC_IC_ACT_LOW, &up->regs->w.ipc);
 979
 980	up->port.ops = &sunsab_pops;
 981	up->port.type = PORT_SUNSAB;
 982	up->port.uartclk = SAB_BASE_BAUD;
 983
 984	up->type = readb(&up->regs->r.vstr) & 0x0f;
 985	writeb(~((1 << 1) | (1 << 2) | (1 << 4)), &up->regs->w.pcr);
 986	writeb(0xff, &up->regs->w.pim);
 987	if ((up->port.line & 0x1) == 0) {
 988		up->pvr_dsr_bit = (1 << 0);
 989		up->pvr_dtr_bit = (1 << 1);
 990		up->gis_shift = 2;
 991	} else {
 992		up->pvr_dsr_bit = (1 << 3);
 993		up->pvr_dtr_bit = (1 << 2);
 994		up->gis_shift = 0;
 995	}
 996	up->cached_pvr = (1 << 1) | (1 << 2) | (1 << 4);
 997	writeb(up->cached_pvr, &up->regs->w.pvr);
 998	up->cached_mode = readb(&up->regs->rw.mode);
 999	up->cached_mode |= SAB82532_MODE_FRTS;
1000	writeb(up->cached_mode, &up->regs->rw.mode);
1001	up->cached_mode |= SAB82532_MODE_RTS;
1002	writeb(up->cached_mode, &up->regs->rw.mode);
1003
1004	up->tec_timeout = SAB82532_MAX_TEC_TIMEOUT;
1005	up->cec_timeout = SAB82532_MAX_CEC_TIMEOUT;
1006
1007	return 0;
1008}
1009
1010static int __devinit sab_probe(struct platform_device *op)
1011{
1012	static int inst;
1013	struct uart_sunsab_port *up;
1014	int err;
1015
1016	up = &sunsab_ports[inst * 2];
1017
1018	err = sunsab_init_one(&up[0], op,
1019			      0,
1020			      (inst * 2) + 0);
1021	if (err)
1022		goto out;
1023
1024	err = sunsab_init_one(&up[1], op,
1025			      sizeof(union sab82532_async_regs),
1026			      (inst * 2) + 1);
1027	if (err)
1028		goto out1;
1029
1030	sunserial_console_match(SUNSAB_CONSOLE(), op->dev.of_node,
1031				&sunsab_reg, up[0].port.line,
1032				false);
1033
1034	sunserial_console_match(SUNSAB_CONSOLE(), op->dev.of_node,
1035				&sunsab_reg, up[1].port.line,
1036				false);
1037
1038	err = uart_add_one_port(&sunsab_reg, &up[0].port);
1039	if (err)
1040		goto out2;
1041
1042	err = uart_add_one_port(&sunsab_reg, &up[1].port);
1043	if (err)
1044		goto out3;
1045
1046	dev_set_drvdata(&op->dev, &up[0]);
1047
1048	inst++;
1049
1050	return 0;
1051
1052out3:
1053	uart_remove_one_port(&sunsab_reg, &up[0].port);
1054out2:
1055	of_iounmap(&op->resource[0],
1056		   up[1].port.membase,
1057		   sizeof(union sab82532_async_regs));
1058out1:
1059	of_iounmap(&op->resource[0],
1060		   up[0].port.membase,
1061		   sizeof(union sab82532_async_regs));
1062out:
1063	return err;
1064}
1065
1066static int __devexit sab_remove(struct platform_device *op)
1067{
1068	struct uart_sunsab_port *up = dev_get_drvdata(&op->dev);
1069
1070	uart_remove_one_port(&sunsab_reg, &up[1].port);
1071	uart_remove_one_port(&sunsab_reg, &up[0].port);
1072	of_iounmap(&op->resource[0],
1073		   up[1].port.membase,
1074		   sizeof(union sab82532_async_regs));
1075	of_iounmap(&op->resource[0],
1076		   up[0].port.membase,
1077		   sizeof(union sab82532_async_regs));
1078
1079	dev_set_drvdata(&op->dev, NULL);
1080
1081	return 0;
1082}
1083
1084static const struct of_device_id sab_match[] = {
1085	{
1086		.name = "se",
1087	},
1088	{
1089		.name = "serial",
1090		.compatible = "sab82532",
1091	},
1092	{},
1093};
1094MODULE_DEVICE_TABLE(of, sab_match);
1095
1096static struct platform_driver sab_driver = {
1097	.driver = {
1098		.name = "sab",
1099		.owner = THIS_MODULE,
1100		.of_match_table = sab_match,
1101	},
1102	.probe		= sab_probe,
1103	.remove		= __devexit_p(sab_remove),
1104};
1105
1106static int __init sunsab_init(void)
1107{
1108	struct device_node *dp;
1109	int err;
1110	int num_channels = 0;
1111
1112	for_each_node_by_name(dp, "se")
1113		num_channels += 2;
1114	for_each_node_by_name(dp, "serial") {
1115		if (of_device_is_compatible(dp, "sab82532"))
1116			num_channels += 2;
1117	}
1118
1119	if (num_channels) {
1120		sunsab_ports = kzalloc(sizeof(struct uart_sunsab_port) *
1121				       num_channels, GFP_KERNEL);
 
1122		if (!sunsab_ports)
1123			return -ENOMEM;
1124
1125		err = sunserial_register_minors(&sunsab_reg, num_channels);
1126		if (err) {
1127			kfree(sunsab_ports);
1128			sunsab_ports = NULL;
1129
1130			return err;
1131		}
1132	}
1133
1134	return platform_driver_register(&sab_driver);
 
 
 
 
 
 
1135}
1136
1137static void __exit sunsab_exit(void)
1138{
1139	platform_driver_unregister(&sab_driver);
1140	if (sunsab_reg.nr) {
1141		sunserial_unregister_minors(&sunsab_reg, sunsab_reg.nr);
1142	}
1143
1144	kfree(sunsab_ports);
1145	sunsab_ports = NULL;
1146}
1147
1148module_init(sunsab_init);
1149module_exit(sunsab_exit);
1150
1151MODULE_AUTHOR("Eddie C. Dost and David S. Miller");
1152MODULE_DESCRIPTION("Sun SAB82532 serial port driver");
1153MODULE_LICENSE("GPL");