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1/****************************************************************************/
2
3/*
4 * mcf.c -- Freescale ColdFire UART driver
5 *
6 * (C) Copyright 2003-2007, Greg Ungerer <gerg@snapgear.com>
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
12 */
13
14/****************************************************************************/
15
16#include <linux/kernel.h>
17#include <linux/init.h>
18#include <linux/interrupt.h>
19#include <linux/module.h>
20#include <linux/console.h>
21#include <linux/tty.h>
22#include <linux/tty_flip.h>
23#include <linux/serial.h>
24#include <linux/serial_core.h>
25#include <linux/io.h>
26#include <asm/coldfire.h>
27#include <asm/mcfsim.h>
28#include <asm/mcfuart.h>
29#include <asm/nettel.h>
30
31/****************************************************************************/
32
33/*
34 * Some boards implement the DTR/DCD lines using GPIO lines, most
35 * don't. Dummy out the access macros for those that don't. Those
36 * that do should define these macros somewhere in there board
37 * specific inlude files.
38 */
39#if !defined(mcf_getppdcd)
40#define mcf_getppdcd(p) (1)
41#endif
42#if !defined(mcf_getppdtr)
43#define mcf_getppdtr(p) (1)
44#endif
45#if !defined(mcf_setppdtr)
46#define mcf_setppdtr(p, v) do { } while (0)
47#endif
48
49/****************************************************************************/
50
51/*
52 * Local per-uart structure.
53 */
54struct mcf_uart {
55 struct uart_port port;
56 unsigned int sigs; /* Local copy of line sigs */
57 unsigned char imr; /* Local IMR mirror */
58};
59
60/****************************************************************************/
61
62static unsigned int mcf_tx_empty(struct uart_port *port)
63{
64 return (readb(port->membase + MCFUART_USR) & MCFUART_USR_TXEMPTY) ?
65 TIOCSER_TEMT : 0;
66}
67
68/****************************************************************************/
69
70static unsigned int mcf_get_mctrl(struct uart_port *port)
71{
72 struct mcf_uart *pp = (struct mcf_uart *) port;
73 unsigned long flags;
74 unsigned int sigs;
75
76 spin_lock_irqsave(&port->lock, flags);
77 sigs = (readb(port->membase + MCFUART_UIPR) & MCFUART_UIPR_CTS) ?
78 0 : TIOCM_CTS;
79 sigs |= (pp->sigs & TIOCM_RTS);
80 sigs |= (mcf_getppdcd(port->line) ? TIOCM_CD : 0);
81 sigs |= (mcf_getppdtr(port->line) ? TIOCM_DTR : 0);
82 spin_unlock_irqrestore(&port->lock, flags);
83 return sigs;
84}
85
86/****************************************************************************/
87
88static void mcf_set_mctrl(struct uart_port *port, unsigned int sigs)
89{
90 struct mcf_uart *pp = (struct mcf_uart *) port;
91 unsigned long flags;
92
93 spin_lock_irqsave(&port->lock, flags);
94 pp->sigs = sigs;
95 mcf_setppdtr(port->line, (sigs & TIOCM_DTR));
96 if (sigs & TIOCM_RTS)
97 writeb(MCFUART_UOP_RTS, port->membase + MCFUART_UOP1);
98 else
99 writeb(MCFUART_UOP_RTS, port->membase + MCFUART_UOP0);
100 spin_unlock_irqrestore(&port->lock, flags);
101}
102
103/****************************************************************************/
104
105static void mcf_start_tx(struct uart_port *port)
106{
107 struct mcf_uart *pp = (struct mcf_uart *) port;
108 unsigned long flags;
109
110 spin_lock_irqsave(&port->lock, flags);
111 pp->imr |= MCFUART_UIR_TXREADY;
112 writeb(pp->imr, port->membase + MCFUART_UIMR);
113 spin_unlock_irqrestore(&port->lock, flags);
114}
115
116/****************************************************************************/
117
118static void mcf_stop_tx(struct uart_port *port)
119{
120 struct mcf_uart *pp = (struct mcf_uart *) port;
121 unsigned long flags;
122
123 spin_lock_irqsave(&port->lock, flags);
124 pp->imr &= ~MCFUART_UIR_TXREADY;
125 writeb(pp->imr, port->membase + MCFUART_UIMR);
126 spin_unlock_irqrestore(&port->lock, flags);
127}
128
129/****************************************************************************/
130
131static void mcf_stop_rx(struct uart_port *port)
132{
133 struct mcf_uart *pp = (struct mcf_uart *) port;
134 unsigned long flags;
135
136 spin_lock_irqsave(&port->lock, flags);
137 pp->imr &= ~MCFUART_UIR_RXREADY;
138 writeb(pp->imr, port->membase + MCFUART_UIMR);
139 spin_unlock_irqrestore(&port->lock, flags);
140}
141
142/****************************************************************************/
143
144static void mcf_break_ctl(struct uart_port *port, int break_state)
145{
146 unsigned long flags;
147
148 spin_lock_irqsave(&port->lock, flags);
149 if (break_state == -1)
150 writeb(MCFUART_UCR_CMDBREAKSTART, port->membase + MCFUART_UCR);
151 else
152 writeb(MCFUART_UCR_CMDBREAKSTOP, port->membase + MCFUART_UCR);
153 spin_unlock_irqrestore(&port->lock, flags);
154}
155
156/****************************************************************************/
157
158static void mcf_enable_ms(struct uart_port *port)
159{
160}
161
162/****************************************************************************/
163
164static int mcf_startup(struct uart_port *port)
165{
166 struct mcf_uart *pp = (struct mcf_uart *) port;
167 unsigned long flags;
168
169 spin_lock_irqsave(&port->lock, flags);
170
171 /* Reset UART, get it into known state... */
172 writeb(MCFUART_UCR_CMDRESETRX, port->membase + MCFUART_UCR);
173 writeb(MCFUART_UCR_CMDRESETTX, port->membase + MCFUART_UCR);
174
175 /* Enable the UART transmitter and receiver */
176 writeb(MCFUART_UCR_RXENABLE | MCFUART_UCR_TXENABLE,
177 port->membase + MCFUART_UCR);
178
179 /* Enable RX interrupts now */
180 pp->imr = MCFUART_UIR_RXREADY;
181 writeb(pp->imr, port->membase + MCFUART_UIMR);
182
183 spin_unlock_irqrestore(&port->lock, flags);
184
185 return 0;
186}
187
188/****************************************************************************/
189
190static void mcf_shutdown(struct uart_port *port)
191{
192 struct mcf_uart *pp = (struct mcf_uart *) port;
193 unsigned long flags;
194
195 spin_lock_irqsave(&port->lock, flags);
196
197 /* Disable all interrupts now */
198 pp->imr = 0;
199 writeb(pp->imr, port->membase + MCFUART_UIMR);
200
201 /* Disable UART transmitter and receiver */
202 writeb(MCFUART_UCR_CMDRESETRX, port->membase + MCFUART_UCR);
203 writeb(MCFUART_UCR_CMDRESETTX, port->membase + MCFUART_UCR);
204
205 spin_unlock_irqrestore(&port->lock, flags);
206}
207
208/****************************************************************************/
209
210static void mcf_set_termios(struct uart_port *port, struct ktermios *termios,
211 struct ktermios *old)
212{
213 unsigned long flags;
214 unsigned int baud, baudclk;
215 unsigned char mr1, mr2;
216
217 baud = uart_get_baud_rate(port, termios, old, 0, 230400);
218 baudclk = ((MCF_BUSCLK / baud) + 16) / 32;
219
220 mr1 = MCFUART_MR1_RXIRQRDY | MCFUART_MR1_RXERRCHAR;
221 mr2 = 0;
222
223 switch (termios->c_cflag & CSIZE) {
224 case CS5: mr1 |= MCFUART_MR1_CS5; break;
225 case CS6: mr1 |= MCFUART_MR1_CS6; break;
226 case CS7: mr1 |= MCFUART_MR1_CS7; break;
227 case CS8:
228 default: mr1 |= MCFUART_MR1_CS8; break;
229 }
230
231 if (termios->c_cflag & PARENB) {
232 if (termios->c_cflag & CMSPAR) {
233 if (termios->c_cflag & PARODD)
234 mr1 |= MCFUART_MR1_PARITYMARK;
235 else
236 mr1 |= MCFUART_MR1_PARITYSPACE;
237 } else {
238 if (termios->c_cflag & PARODD)
239 mr1 |= MCFUART_MR1_PARITYODD;
240 else
241 mr1 |= MCFUART_MR1_PARITYEVEN;
242 }
243 } else {
244 mr1 |= MCFUART_MR1_PARITYNONE;
245 }
246
247 if (termios->c_cflag & CSTOPB)
248 mr2 |= MCFUART_MR2_STOP2;
249 else
250 mr2 |= MCFUART_MR2_STOP1;
251
252 if (termios->c_cflag & CRTSCTS) {
253 mr1 |= MCFUART_MR1_RXRTS;
254 mr2 |= MCFUART_MR2_TXCTS;
255 }
256
257 spin_lock_irqsave(&port->lock, flags);
258 writeb(MCFUART_UCR_CMDRESETRX, port->membase + MCFUART_UCR);
259 writeb(MCFUART_UCR_CMDRESETTX, port->membase + MCFUART_UCR);
260 writeb(MCFUART_UCR_CMDRESETMRPTR, port->membase + MCFUART_UCR);
261 writeb(mr1, port->membase + MCFUART_UMR);
262 writeb(mr2, port->membase + MCFUART_UMR);
263 writeb((baudclk & 0xff00) >> 8, port->membase + MCFUART_UBG1);
264 writeb((baudclk & 0xff), port->membase + MCFUART_UBG2);
265 writeb(MCFUART_UCSR_RXCLKTIMER | MCFUART_UCSR_TXCLKTIMER,
266 port->membase + MCFUART_UCSR);
267 writeb(MCFUART_UCR_RXENABLE | MCFUART_UCR_TXENABLE,
268 port->membase + MCFUART_UCR);
269 spin_unlock_irqrestore(&port->lock, flags);
270}
271
272/****************************************************************************/
273
274static void mcf_rx_chars(struct mcf_uart *pp)
275{
276 struct uart_port *port = (struct uart_port *) pp;
277 unsigned char status, ch, flag;
278
279 while ((status = readb(port->membase + MCFUART_USR)) & MCFUART_USR_RXREADY) {
280 ch = readb(port->membase + MCFUART_URB);
281 flag = TTY_NORMAL;
282 port->icount.rx++;
283
284 if (status & MCFUART_USR_RXERR) {
285 writeb(MCFUART_UCR_CMDRESETERR,
286 port->membase + MCFUART_UCR);
287
288 if (status & MCFUART_USR_RXBREAK) {
289 port->icount.brk++;
290 if (uart_handle_break(port))
291 continue;
292 } else if (status & MCFUART_USR_RXPARITY) {
293 port->icount.parity++;
294 } else if (status & MCFUART_USR_RXOVERRUN) {
295 port->icount.overrun++;
296 } else if (status & MCFUART_USR_RXFRAMING) {
297 port->icount.frame++;
298 }
299
300 status &= port->read_status_mask;
301
302 if (status & MCFUART_USR_RXBREAK)
303 flag = TTY_BREAK;
304 else if (status & MCFUART_USR_RXPARITY)
305 flag = TTY_PARITY;
306 else if (status & MCFUART_USR_RXFRAMING)
307 flag = TTY_FRAME;
308 }
309
310 if (uart_handle_sysrq_char(port, ch))
311 continue;
312 uart_insert_char(port, status, MCFUART_USR_RXOVERRUN, ch, flag);
313 }
314
315 tty_flip_buffer_push(port->info->tty);
316}
317
318/****************************************************************************/
319
320static void mcf_tx_chars(struct mcf_uart *pp)
321{
322 struct uart_port *port = (struct uart_port *) pp;
323 struct circ_buf *xmit = &port->info->xmit;
324
325 if (port->x_char) {
326 /* Send special char - probably flow control */
327 writeb(port->x_char, port->membase + MCFUART_UTB);
328 port->x_char = 0;
329 port->icount.tx++;
330 return;
331 }
332
333 while (readb(port->membase + MCFUART_USR) & MCFUART_USR_TXREADY) {
334 if (xmit->head == xmit->tail)
335 break;
336 writeb(xmit->buf[xmit->tail], port->membase + MCFUART_UTB);
337 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE -1);
338 port->icount.tx++;
339 }
340
341 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
342 uart_write_wakeup(port);
343
344 if (xmit->head == xmit->tail) {
345 pp->imr &= ~MCFUART_UIR_TXREADY;
346 writeb(pp->imr, port->membase + MCFUART_UIMR);
347 }
348}
349
350/****************************************************************************/
351
352static irqreturn_t mcf_interrupt(int irq, void *data)
353{
354 struct uart_port *port = data;
355 struct mcf_uart *pp = (struct mcf_uart *) port;
356 unsigned int isr;
357
358 isr = readb(port->membase + MCFUART_UISR) & pp->imr;
359 if (isr & MCFUART_UIR_RXREADY)
360 mcf_rx_chars(pp);
361 if (isr & MCFUART_UIR_TXREADY)
362 mcf_tx_chars(pp);
363 return IRQ_HANDLED;
364}
365
366/****************************************************************************/
367
368static void mcf_config_port(struct uart_port *port, int flags)
369{
370 port->type = PORT_MCF;
371
372 /* Clear mask, so no surprise interrupts. */
373 writeb(0, port->membase + MCFUART_UIMR);
374
375 if (request_irq(port->irq, mcf_interrupt, IRQF_DISABLED, "UART", port))
376 printk(KERN_ERR "MCF: unable to attach ColdFire UART %d "
377 "interrupt vector=%d\n", port->line, port->irq);
378}
379
380/****************************************************************************/
381
382static const char *mcf_type(struct uart_port *port)
383{
384 return (port->type == PORT_MCF) ? "ColdFire UART" : NULL;
385}
386
387/****************************************************************************/
388
389static int mcf_request_port(struct uart_port *port)
390{
391 /* UARTs always present */
392 return 0;
393}
394
395/****************************************************************************/
396
397static void mcf_release_port(struct uart_port *port)
398{
399 /* Nothing to release... */
400}
401
402/****************************************************************************/
403
404static int mcf_verify_port(struct uart_port *port, struct serial_struct *ser)
405{
406 if ((ser->type != PORT_UNKNOWN) && (ser->type != PORT_MCF))
407 return -EINVAL;
408 return 0;
409}
410
411/****************************************************************************/
412
413/*
414 * Define the basic serial functions we support.
415 */
416static struct uart_ops mcf_uart_ops = {
417 .tx_empty = mcf_tx_empty,
418 .get_mctrl = mcf_get_mctrl,
419 .set_mctrl = mcf_set_mctrl,
420 .start_tx = mcf_start_tx,
421 .stop_tx = mcf_stop_tx,
422 .stop_rx = mcf_stop_rx,
423 .enable_ms = mcf_enable_ms,
424 .break_ctl = mcf_break_ctl,
425 .startup = mcf_startup,
426 .shutdown = mcf_shutdown,
427 .set_termios = mcf_set_termios,
428 .type = mcf_type,
429 .request_port = mcf_request_port,
430 .release_port = mcf_release_port,
431 .config_port = mcf_config_port,
432 .verify_port = mcf_verify_port,
433};
434
435static struct mcf_uart mcf_ports[3];
436
437#define MCF_MAXPORTS (sizeof(mcf_ports) / sizeof(struct mcf_uart))
438
439/****************************************************************************/
440#if defined(CONFIG_SERIAL_MCF_CONSOLE)
441/****************************************************************************/
442
443int __init early_mcf_setup(struct mcf_platform_uart *platp)
444{
445 struct uart_port *port;
446 int i;
447
448 for (i = 0; ((i < MCF_MAXPORTS) && (platp[i].mapbase)); i++) {
449 port = &mcf_ports[i].port;
450
451 port->line = i;
452 port->type = PORT_MCF;
453 port->mapbase = platp[i].mapbase;
454 port->membase = (platp[i].membase) ? platp[i].membase :
455 (unsigned char __iomem *) port->mapbase;
456 port->iotype = SERIAL_IO_MEM;
457 port->irq = platp[i].irq;
458 port->uartclk = MCF_BUSCLK;
459 port->flags = ASYNC_BOOT_AUTOCONF;
460 port->ops = &mcf_uart_ops;
461 }
462
463 return 0;
464}
465
466/****************************************************************************/
467
468static void mcf_console_putc(struct console *co, const char c)
469{
470 struct uart_port *port = &(mcf_ports + co->index)->port;
471 int i;
472
473 for (i = 0; (i < 0x10000); i++) {
474 if (readb(port->membase + MCFUART_USR) & MCFUART_USR_TXREADY)
475 break;
476 }
477 writeb(c, port->membase + MCFUART_UTB);
478 for (i = 0; (i < 0x10000); i++) {
479 if (readb(port->membase + MCFUART_USR) & MCFUART_USR_TXREADY)
480 break;
481 }
482}
483
484/****************************************************************************/
485
486static void mcf_console_write(struct console *co, const char *s, unsigned int count)
487{
488 for (; (count); count--, s++) {
489 mcf_console_putc(co, *s);
490 if (*s == '\n')
491 mcf_console_putc(co, '\r');
492 }
493}
494
495/****************************************************************************/
496
497static int __init mcf_console_setup(struct console *co, char *options)
498{
499 struct uart_port *port;
500 int baud = CONFIG_SERIAL_MCF_BAUDRATE;
501 int bits = 8;
502 int parity = 'n';
503 int flow = 'n';
504
505 if ((co->index >= 0) && (co->index <= MCF_MAXPORTS))
506 co->index = 0;
507 port = &mcf_ports[co->index].port;
508 if (port->membase == 0)
509 return -ENODEV;
510
511 if (options)
512 uart_parse_options(options, &baud, &parity, &bits, &flow);
513
514 return uart_set_options(port, co, baud, parity, bits, flow);
515}
516
517/****************************************************************************/
518
519static struct uart_driver mcf_driver;
520
521static struct console mcf_console = {
522 .name = "ttyS",
523 .write = mcf_console_write,
524 .device = uart_console_device,
525 .setup = mcf_console_setup,
526 .flags = CON_PRINTBUFFER,
527 .index = -1,
528 .data = &mcf_driver,
529};
530
531static int __init mcf_console_init(void)
532{
533 register_console(&mcf_console);
534 return 0;
535}
536
537console_initcall(mcf_console_init);
538
539#define MCF_CONSOLE &mcf_console
540
541/****************************************************************************/
542#else
543/****************************************************************************/
544
545#define MCF_CONSOLE NULL
546
547/****************************************************************************/
548#endif /* CONFIG_MCF_CONSOLE */
549/****************************************************************************/
550
551/*
552 * Define the mcf UART driver structure.
553 */
554static struct uart_driver mcf_driver = {
555 .owner = THIS_MODULE,
556 .driver_name = "mcf",
557 .dev_name = "ttyS",
558 .major = TTY_MAJOR,
559 .minor = 64,
560 .nr = MCF_MAXPORTS,
561 .cons = MCF_CONSOLE,
562};
563
564/****************************************************************************/
565
566static int __devinit mcf_probe(struct platform_device *pdev)
567{
568 struct mcf_platform_uart *platp = pdev->dev.platform_data;
569 struct uart_port *port;
570 int i;
571
572 for (i = 0; ((i < MCF_MAXPORTS) && (platp[i].mapbase)); i++) {
573 port = &mcf_ports[i].port;
574
575 port->line = i;
576 port->type = PORT_MCF;
577 port->mapbase = platp[i].mapbase;
578 port->membase = (platp[i].membase) ? platp[i].membase :
579 (unsigned char __iomem *) platp[i].mapbase;
580 port->iotype = SERIAL_IO_MEM;
581 port->irq = platp[i].irq;
582 port->uartclk = MCF_BUSCLK;
583 port->ops = &mcf_uart_ops;
584 port->flags = ASYNC_BOOT_AUTOCONF;
585
586 uart_add_one_port(&mcf_driver, port);
587 }
588
589 return 0;
590}
591
592/****************************************************************************/
593
594static int mcf_remove(struct platform_device *pdev)
595{
596 struct uart_port *port;
597 int i;
598
599 for (i = 0; (i < MCF_MAXPORTS); i++) {
600 port = &mcf_ports[i].port;
601 if (port)
602 uart_remove_one_port(&mcf_driver, port);
603 }
604
605 return 0;
606}
607
608/****************************************************************************/
609
610static struct platform_driver mcf_platform_driver = {
611 .probe = mcf_probe,
612 .remove = __devexit_p(mcf_remove),
613 .driver = {
614 .name = "mcfuart",
615 .owner = THIS_MODULE,
616 },
617};
618
619/****************************************************************************/
620
621static int __init mcf_init(void)
622{
623 int rc;
624
625 printk("ColdFire internal UART serial driver\n");
626
627 rc = uart_register_driver(&mcf_driver);
628 if (rc)
629 return rc;
630 rc = platform_driver_register(&mcf_platform_driver);
631 if (rc)
632 return rc;
633 return 0;
634}
635
636/****************************************************************************/
637
638static void __exit mcf_exit(void)
639{
640 platform_driver_unregister(&mcf_platform_driver);
641 uart_unregister_driver(&mcf_driver);
642}
643
644/****************************************************************************/
645
646module_init(mcf_init);
647module_exit(mcf_exit);
648
649MODULE_AUTHOR("Greg Ungerer <gerg@snapgear.com>");
650MODULE_DESCRIPTION("Freescale ColdFire UART driver");
651MODULE_LICENSE("GPL");
652
653/****************************************************************************/