summaryrefslogtreecommitdiff
path: root/drivers/tty/serial/mcf.c
blob: e2b93d2f8f8c8ba6f5e06df0ce30151b5b35c9d2 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
/****************************************************************************/

/*
 *	mcf.c -- Freescale ColdFire UART driver
 *
 *	(C) Copyright 2003-2007, Greg Ungerer <gerg@snapgear.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 */

/****************************************************************************/

#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/console.h>
#include <linux/tty.h>
#include <linux/tty_flip.h>
#include <linux/serial.h>
#include <linux/serial_core.h>
#include <linux/io.h>
#include <asm/coldfire.h>
#include <asm/mcfsim.h>
#include <asm/mcfuart.h>
#include <asm/nettel.h>

/****************************************************************************/

/*
 *	Some boards implement the DTR/DCD lines using GPIO lines, most
 *	don't. Dummy out the access macros for those that don't. Those
 *	that do should define these macros somewhere in there board
 *	specific inlude files.
 */
#if !defined(mcf_getppdcd)
#define	mcf_getppdcd(p)		(1)
#endif
#if !defined(mcf_getppdtr)
#define	mcf_getppdtr(p)		(1)
#endif
#if !defined(mcf_setppdtr)
#define	mcf_setppdtr(p, v)	do { } while (0)
#endif

/****************************************************************************/

/*
 *	Local per-uart structure.
 */
struct mcf_uart {
	struct uart_port	port;
	unsigned int		sigs;		/* Local copy of line sigs */
	unsigned char		imr;		/* Local IMR mirror */
};

/****************************************************************************/

static unsigned int mcf_tx_empty(struct uart_port *port)
{
	return (readb(port->membase + MCFUART_USR) & MCFUART_USR_TXEMPTY) ?
		TIOCSER_TEMT : 0;
}

/****************************************************************************/

static unsigned int mcf_get_mctrl(struct uart_port *port)
{
	struct mcf_uart *pp = container_of(port, struct mcf_uart, port);
	unsigned int sigs;

	sigs = (readb(port->membase + MCFUART_UIPR) & MCFUART_UIPR_CTS) ?
		0 : TIOCM_CTS;
	sigs |= (pp->sigs & TIOCM_RTS);
	sigs |= (mcf_getppdcd(port->line) ? TIOCM_CD : 0);
	sigs |= (mcf_getppdtr(port->line) ? TIOCM_DTR : 0);

	return sigs;
}

/****************************************************************************/

static void mcf_set_mctrl(struct uart_port *port, unsigned int sigs)
{
	struct mcf_uart *pp = container_of(port, struct mcf_uart, port);

	pp->sigs = sigs;
	mcf_setppdtr(port->line, (sigs & TIOCM_DTR));
	if (sigs & TIOCM_RTS)
		writeb(MCFUART_UOP_RTS, port->membase + MCFUART_UOP1);
	else
		writeb(MCFUART_UOP_RTS, port->membase + MCFUART_UOP0);
}

/****************************************************************************/

static void mcf_start_tx(struct uart_port *port)
{
	struct mcf_uart *pp = container_of(port, struct mcf_uart, port);

	pp->imr |= MCFUART_UIR_TXREADY;
	writeb(pp->imr, port->membase + MCFUART_UIMR);
}

/****************************************************************************/

static void mcf_stop_tx(struct uart_port *port)
{
	struct mcf_uart *pp = container_of(port, struct mcf_uart, port);

	pp->imr &= ~MCFUART_UIR_TXREADY;
	writeb(pp->imr, port->membase + MCFUART_UIMR);
}

/****************************************************************************/

static void mcf_stop_rx(struct uart_port *port)
{
	struct mcf_uart *pp = container_of(port, struct mcf_uart, port);

	pp->imr &= ~MCFUART_UIR_RXREADY;
	writeb(pp->imr, port->membase + MCFUART_UIMR);
}

/****************************************************************************/

static void mcf_break_ctl(struct uart_port *port, int break_state)
{
	unsigned long flags;

	spin_lock_irqsave(&port->lock, flags);
	if (break_state == -1)
		writeb(MCFUART_UCR_CMDBREAKSTART, port->membase + MCFUART_UCR);
	else
		writeb(MCFUART_UCR_CMDBREAKSTOP, port->membase + MCFUART_UCR);
	spin_unlock_irqrestore(&port->lock, flags);
}

/****************************************************************************/

static void mcf_enable_ms(struct uart_port *port)
{
}

/****************************************************************************/

static int mcf_startup(struct uart_port *port)
{
	struct mcf_uart *pp = container_of(port, struct mcf_uart, port);
	unsigned long flags;

	spin_lock_irqsave(&port->lock, flags);

	/* Reset UART, get it into known state... */
	writeb(MCFUART_UCR_CMDRESETRX, port->membase + MCFUART_UCR);
	writeb(MCFUART_UCR_CMDRESETTX, port->membase + MCFUART_UCR);

	/* Enable the UART transmitter and receiver */
	writeb(MCFUART_UCR_RXENABLE | MCFUART_UCR_TXENABLE,
		port->membase + MCFUART_UCR);

	/* Enable RX interrupts now */
	pp->imr = MCFUART_UIR_RXREADY;
	writeb(pp->imr, port->membase + MCFUART_UIMR);

	spin_unlock_irqrestore(&port->lock, flags);

	return 0;
}

/****************************************************************************/

static void mcf_shutdown(struct uart_port *port)
{
	struct mcf_uart *pp = container_of(port, struct mcf_uart, port);
	unsigned long flags;

	spin_lock_irqsave(&port->lock, flags);

	/* Disable all interrupts now */
	pp->imr = 0;
	writeb(pp->imr, port->membase + MCFUART_UIMR);

	/* Disable UART transmitter and receiver */
	writeb(MCFUART_UCR_CMDRESETRX, port->membase + MCFUART_UCR);
	writeb(MCFUART_UCR_CMDRESETTX, port->membase + MCFUART_UCR);

	spin_unlock_irqrestore(&port->lock, flags);
}

/****************************************************************************/

static void mcf_set_termios(struct uart_port *port, struct ktermios *termios,
	struct ktermios *old)
{
	unsigned long flags;
	unsigned int baud, baudclk;
#if defined(CONFIG_M5272)
	unsigned int baudfr;
#endif
	unsigned char mr1, mr2;

	baud = uart_get_baud_rate(port, termios, old, 0, 230400);
#if defined(CONFIG_M5272)
	baudclk = (MCF_BUSCLK / baud) / 32;
	baudfr = (((MCF_BUSCLK / baud) + 1) / 2) % 16;
#else
	baudclk = ((MCF_BUSCLK / baud) + 16) / 32;
#endif

	mr1 = MCFUART_MR1_RXIRQRDY | MCFUART_MR1_RXERRCHAR;
	mr2 = 0;

	switch (termios->c_cflag & CSIZE) {
	case CS5: mr1 |= MCFUART_MR1_CS5; break;
	case CS6: mr1 |= MCFUART_MR1_CS6; break;
	case CS7: mr1 |= MCFUART_MR1_CS7; break;
	case CS8:
	default:  mr1 |= MCFUART_MR1_CS8; break;
	}

	if (termios->c_cflag & PARENB) {
		if (termios->c_cflag & CMSPAR) {
			if (termios->c_cflag & PARODD)
				mr1 |= MCFUART_MR1_PARITYMARK;
			else
				mr1 |= MCFUART_MR1_PARITYSPACE;
		} else {
			if (termios->c_cflag & PARODD)
				mr1 |= MCFUART_MR1_PARITYODD;
			else
				mr1 |= MCFUART_MR1_PARITYEVEN;
		}
	} else {
		mr1 |= MCFUART_MR1_PARITYNONE;
	}

	if (termios->c_cflag & CSTOPB)
		mr2 |= MCFUART_MR2_STOP2;
	else
		mr2 |= MCFUART_MR2_STOP1;

	if (termios->c_cflag & CRTSCTS) {
		mr1 |= MCFUART_MR1_RXRTS;
		mr2 |= MCFUART_MR2_TXCTS;
	}

	spin_lock_irqsave(&port->lock, flags);
	uart_update_timeout(port, termios->c_cflag, baud);
	writeb(MCFUART_UCR_CMDRESETRX, port->membase + MCFUART_UCR);
	writeb(MCFUART_UCR_CMDRESETTX, port->membase + MCFUART_UCR);
	writeb(MCFUART_UCR_CMDRESETMRPTR, port->membase + MCFUART_UCR);
	writeb(mr1, port->membase + MCFUART_UMR);
	writeb(mr2, port->membase + MCFUART_UMR);
	writeb((baudclk & 0xff00) >> 8, port->membase + MCFUART_UBG1);
	writeb((baudclk & 0xff), port->membase + MCFUART_UBG2);
#if defined(CONFIG_M5272)
	writeb((baudfr & 0x0f), port->membase + MCFUART_UFPD);
#endif
	writeb(MCFUART_UCSR_RXCLKTIMER | MCFUART_UCSR_TXCLKTIMER,
		port->membase + MCFUART_UCSR);
	writeb(MCFUART_UCR_RXENABLE | MCFUART_UCR_TXENABLE,
		port->membase + MCFUART_UCR);
	spin_unlock_irqrestore(&port->lock, flags);
}

/****************************************************************************/

static void mcf_rx_chars(struct mcf_uart *pp)
{
	struct uart_port *port = &pp->port;
	unsigned char status, ch, flag;

	while ((status = readb(port->membase + MCFUART_USR)) & MCFUART_USR_RXREADY) {
		ch = readb(port->membase + MCFUART_URB);
		flag = TTY_NORMAL;
		port->icount.rx++;

		if (status & MCFUART_USR_RXERR) {
			writeb(MCFUART_UCR_CMDRESETERR,
				port->membase + MCFUART_UCR);

			if (status & MCFUART_USR_RXBREAK) {
				port->icount.brk++;
				if (uart_handle_break(port))
					continue;
			} else if (status & MCFUART_USR_RXPARITY) {
				port->icount.parity++;
			} else if (status & MCFUART_USR_RXOVERRUN) {
				port->icount.overrun++;
			} else if (status & MCFUART_USR_RXFRAMING) {
				port->icount.frame++;
			}

			status &= port->read_status_mask;

			if (status & MCFUART_USR_RXBREAK)
				flag = TTY_BREAK;
			else if (status & MCFUART_USR_RXPARITY)
				flag = TTY_PARITY;
			else if (status & MCFUART_USR_RXFRAMING)
				flag = TTY_FRAME;
		}

		if (uart_handle_sysrq_char(port, ch))
			continue;
		uart_insert_char(port, status, MCFUART_USR_RXOVERRUN, ch, flag);
	}

	tty_flip_buffer_push(port->state->port.tty);
}

/****************************************************************************/

static void mcf_tx_chars(struct mcf_uart *pp)
{
	struct uart_port *port = &pp->port;
	struct circ_buf *xmit = &port->state->xmit;

	if (port->x_char) {
		/* Send special char - probably flow control */
		writeb(port->x_char, port->membase + MCFUART_UTB);
		port->x_char = 0;
		port->icount.tx++;
		return;
	}

	while (readb(port->membase + MCFUART_USR) & MCFUART_USR_TXREADY) {
		if (xmit->head == xmit->tail)
			break;
		writeb(xmit->buf[xmit->tail], port->membase + MCFUART_UTB);
		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE -1);
		port->icount.tx++;
	}

	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
		uart_write_wakeup(port);

	if (xmit->head == xmit->tail) {
		pp->imr &= ~MCFUART_UIR_TXREADY;
		writeb(pp->imr, port->membase + MCFUART_UIMR);
	}
}

/****************************************************************************/

static irqreturn_t mcf_interrupt(int irq, void *data)
{
	struct uart_port *port = data;
	struct mcf_uart *pp = container_of(port, struct mcf_uart, port);
	unsigned int isr;
	irqreturn_t ret = IRQ_NONE;

	isr = readb(port->membase + MCFUART_UISR) & pp->imr;

	spin_lock(&port->lock);
	if (isr & MCFUART_UIR_RXREADY) {
		mcf_rx_chars(pp);
		ret = IRQ_HANDLED;
	}
	if (isr & MCFUART_UIR_TXREADY) {
		mcf_tx_chars(pp);
		ret = IRQ_HANDLED;
	}
	spin_unlock(&port->lock);

	return ret;
}

/****************************************************************************/

static void mcf_config_port(struct uart_port *port, int flags)
{
	port->type = PORT_MCF;
	port->fifosize = MCFUART_TXFIFOSIZE;

	/* Clear mask, so no surprise interrupts. */
	writeb(0, port->membase + MCFUART_UIMR);

	if (request_irq(port->irq, mcf_interrupt, 0, "UART", port))
		printk(KERN_ERR "MCF: unable to attach ColdFire UART %d "
			"interrupt vector=%d\n", port->line, port->irq);
}

/****************************************************************************/

static const char *mcf_type(struct uart_port *port)
{
	return (port->type == PORT_MCF) ? "ColdFire UART" : NULL;
}

/****************************************************************************/

static int mcf_request_port(struct uart_port *port)
{
	/* UARTs always present */
	return 0;
}

/****************************************************************************/

static void mcf_release_port(struct uart_port *port)
{
	/* Nothing to release... */
}

/****************************************************************************/

static int mcf_verify_port(struct uart_port *port, struct serial_struct *ser)
{
	if ((ser->type != PORT_UNKNOWN) && (ser->type != PORT_MCF))
		return -EINVAL;
	return 0;
}

/****************************************************************************/

/*
 *	Define the basic serial functions we support.
 */
static const struct uart_ops mcf_uart_ops = {
	.tx_empty	= mcf_tx_empty,
	.get_mctrl	= mcf_get_mctrl,
	.set_mctrl	= mcf_set_mctrl,
	.start_tx	= mcf_start_tx,
	.stop_tx	= mcf_stop_tx,
	.stop_rx	= mcf_stop_rx,
	.enable_ms	= mcf_enable_ms,
	.break_ctl	= mcf_break_ctl,
	.startup	= mcf_startup,
	.shutdown	= mcf_shutdown,
	.set_termios	= mcf_set_termios,
	.type		= mcf_type,
	.request_port	= mcf_request_port,
	.release_port	= mcf_release_port,
	.config_port	= mcf_config_port,
	.verify_port	= mcf_verify_port,
};

static struct mcf_uart mcf_ports[4];

#define	MCF_MAXPORTS	ARRAY_SIZE(mcf_ports)

/****************************************************************************/
#if defined(CONFIG_SERIAL_MCF_CONSOLE)
/****************************************************************************/

int __init early_mcf_setup(struct mcf_platform_uart *platp)
{
	struct uart_port *port;
	int i;

	for (i = 0; ((i < MCF_MAXPORTS) && (platp[i].mapbase)); i++) {
		port = &mcf_ports[i].port;

		port->line = i;
		port->type = PORT_MCF;
		port->mapbase = platp[i].mapbase;
		port->membase = (platp[i].membase) ? platp[i].membase :
			(unsigned char __iomem *) port->mapbase;
		port->iotype = SERIAL_IO_MEM;
		port->irq = platp[i].irq;
		port->uartclk = MCF_BUSCLK;
		port->flags = ASYNC_BOOT_AUTOCONF;
		port->ops = &mcf_uart_ops;
	}

	return 0;
}

/****************************************************************************/

static void mcf_console_putc(struct console *co, const char c)
{
	struct uart_port *port = &(mcf_ports + co->index)->port;
	int i;

	for (i = 0; (i < 0x10000); i++) {
		if (readb(port->membase + MCFUART_USR) & MCFUART_USR_TXREADY)
			break;
	}
	writeb(c, port->membase + MCFUART_UTB);
	for (i = 0; (i < 0x10000); i++) {
		if (readb(port->membase + MCFUART_USR) & MCFUART_USR_TXREADY)
			break;
	}
}

/****************************************************************************/

static void mcf_console_write(struct console *co, const char *s, unsigned int count)
{
	for (; (count); count--, s++) {
		mcf_console_putc(co, *s);
		if (*s == '\n')
			mcf_console_putc(co, '\r');
	}
}

/****************************************************************************/

static int __init mcf_console_setup(struct console *co, char *options)
{
	struct uart_port *port;
	int baud = CONFIG_SERIAL_MCF_BAUDRATE;
	int bits = 8;
	int parity = 'n';
	int flow = 'n';

	if ((co->index < 0) || (co->index >= MCF_MAXPORTS))
		co->index = 0;
	port = &mcf_ports[co->index].port;
	if (port->membase == 0)
		return -ENODEV;

	if (options)
		uart_parse_options(options, &baud, &parity, &bits, &flow);

	return uart_set_options(port, co, baud, parity, bits, flow);
}

/****************************************************************************/

static struct uart_driver mcf_driver;

static struct console mcf_console = {
	.name		= "ttyS",
	.write		= mcf_console_write,
	.device		= uart_console_device,
	.setup		= mcf_console_setup,
	.flags		= CON_PRINTBUFFER,
	.index		= -1,
	.data		= &mcf_driver,
};

static int __init mcf_console_init(void)
{
	register_console(&mcf_console);
	return 0;
}

console_initcall(mcf_console_init);

#define	MCF_CONSOLE	&mcf_console

/****************************************************************************/
#else
/****************************************************************************/

#define	MCF_CONSOLE	NULL

/****************************************************************************/
#endif /* CONFIG_MCF_CONSOLE */
/****************************************************************************/

/*
 *	Define the mcf UART driver structure.
 */
static struct uart_driver mcf_driver = {
	.owner		= THIS_MODULE,
	.driver_name	= "mcf",
	.dev_name	= "ttyS",
	.major		= TTY_MAJOR,
	.minor		= 64,
	.nr		= MCF_MAXPORTS,
	.cons		= MCF_CONSOLE,
};

/****************************************************************************/

static int mcf_probe(struct platform_device *pdev)
{
	struct mcf_platform_uart *platp = pdev->dev.platform_data;
	struct uart_port *port;
	int i;

	for (i = 0; ((i < MCF_MAXPORTS) && (platp[i].mapbase)); i++) {
		port = &mcf_ports[i].port;

		port->line = i;
		port->type = PORT_MCF;
		port->mapbase = platp[i].mapbase;
		port->membase = (platp[i].membase) ? platp[i].membase :
			(unsigned char __iomem *) platp[i].mapbase;
		port->iotype = SERIAL_IO_MEM;
		port->irq = platp[i].irq;
		port->uartclk = MCF_BUSCLK;
		port->ops = &mcf_uart_ops;
		port->flags = ASYNC_BOOT_AUTOCONF;

		uart_add_one_port(&mcf_driver, port);
	}

	return 0;
}

/****************************************************************************/

static int __devexit mcf_remove(struct platform_device *pdev)
{
	struct uart_port *port;
	int i;

	for (i = 0; (i < MCF_MAXPORTS); i++) {
		port = &mcf_ports[i].port;
		if (port)
			uart_remove_one_port(&mcf_driver, port);
	}

	return 0;
}

/****************************************************************************/

static struct platform_driver mcf_platform_driver = {
	.probe		= mcf_probe,
	.remove		= mcf_remove,
	.driver		= {
		.name	= "mcfuart",
		.owner	= THIS_MODULE,
	},
};

/****************************************************************************/

static int __init mcf_init(void)
{
	int rc;

	printk("ColdFire internal UART serial driver\n");

	rc = uart_register_driver(&mcf_driver);
	if (rc)
		return rc;
	rc = platform_driver_register(&mcf_platform_driver);
	if (rc)
		return rc;
	return 0;
}

/****************************************************************************/

static void __exit mcf_exit(void)
{
	platform_driver_unregister(&mcf_platform_driver);
	uart_unregister_driver(&mcf_driver);
}

/****************************************************************************/

module_init(mcf_init);
module_exit(mcf_exit);

MODULE_AUTHOR("Greg Ungerer <gerg@snapgear.com>");
MODULE_DESCRIPTION("Freescale ColdFire UART driver");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:mcfuart");

/****************************************************************************/