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Merge commit 'v2.6.32.11' into mini2440-stable-v2.6.32
[linux-2.6/mini2440.git] / drivers / serial / sh-sci.c
blob6498bd1fb6dd3952b3b0c3e093675865a9f62051
1 /*
2 * drivers/serial/sh-sci.c
3 *
4 * SuperH on-chip serial module support. (SCI with no FIFO / with FIFO)
5 *
6 * Copyright (C) 2002 - 2008 Paul Mundt
7 * Modified to support SH7720 SCIF. Markus Brunner, Mark Jonas (Jul 2007).
8 *
9 * based off of the old drivers/char/sh-sci.c by:
10 *
11 * Copyright (C) 1999, 2000 Niibe Yutaka
12 * Copyright (C) 2000 Sugioka Toshinobu
13 * Modified to support multiple serial ports. Stuart Menefy (May 2000).
14 * Modified to support SecureEdge. David McCullough (2002)
15 * Modified to support SH7300 SCIF. Takashi Kusuda (Jun 2003).
16 * Removed SH7300 support (Jul 2007).
17 *
18 * This file is subject to the terms and conditions of the GNU General Public
19 * License. See the file "COPYING" in the main directory of this archive
20 * for more details.
21 */
22 #if defined(CONFIG_SERIAL_SH_SCI_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
23 #define SUPPORT_SYSRQ
24 #endif
25
26 #undef DEBUG
27
28 #include <linux/module.h>
29 #include <linux/errno.h>
30 #include <linux/timer.h>
31 #include <linux/interrupt.h>
32 #include <linux/tty.h>
33 #include <linux/tty_flip.h>
34 #include <linux/serial.h>
35 #include <linux/major.h>
36 #include <linux/string.h>
37 #include <linux/sysrq.h>
38 #include <linux/ioport.h>
39 #include <linux/mm.h>
40 #include <linux/init.h>
41 #include <linux/delay.h>
42 #include <linux/console.h>
43 #include <linux/platform_device.h>
44 #include <linux/serial_sci.h>
45 #include <linux/notifier.h>
46 #include <linux/cpufreq.h>
47 #include <linux/clk.h>
48 #include <linux/ctype.h>
49 #include <linux/err.h>
50 #include <linux/list.h>
51
52 #ifdef CONFIG_SUPERH
53 #include <asm/clock.h>
54 #include <asm/sh_bios.h>
55 #endif
56
57 #ifdef CONFIG_H8300
58 #include <asm/gpio.h>
59 #endif
60
61 #include "sh-sci.h"
62
63 struct sci_port {
64 struct uart_port port;
65
66 /* Port type */
67 unsigned int type;
68
69 /* Port IRQs: ERI, RXI, TXI, BRI (optional) */
70 unsigned int irqs[SCIx_NR_IRQS];
71
72 /* Port enable callback */
73 void (*enable)(struct uart_port *port);
74
75 /* Port disable callback */
76 void (*disable)(struct uart_port *port);
77
78 /* Break timer */
79 struct timer_list break_timer;
80 int break_flag;
81
82 #ifdef CONFIG_HAVE_CLK
83 /* Interface clock */
84 struct clk *iclk;
85 /* Data clock */
86 struct clk *dclk;
87 #endif
88 struct list_head node;
89 };
90
91 struct sh_sci_priv {
92 spinlock_t lock;
93 struct list_head ports;
94
95 #ifdef CONFIG_HAVE_CLK
96 struct notifier_block clk_nb;
97 #endif
98 };
99
100 /* Function prototypes */
101 static void sci_stop_tx(struct uart_port *port);
102
103 #define SCI_NPORTS CONFIG_SERIAL_SH_SCI_NR_UARTS
104
105 static struct sci_port sci_ports[SCI_NPORTS];
106 static struct uart_driver sci_uart_driver;
107
108 static inline struct sci_port *
109 to_sci_port(struct uart_port *uart)
110 {
111 return container_of(uart, struct sci_port, port);
112 }
113
114 #if defined(CONFIG_CONSOLE_POLL) || defined(CONFIG_SERIAL_SH_SCI_CONSOLE)
115
116 #ifdef CONFIG_CONSOLE_POLL
117 static inline void handle_error(struct uart_port *port)
118 {
119 /* Clear error flags */
120 sci_out(port, SCxSR, SCxSR_ERROR_CLEAR(port));
121 }
122
123 static int sci_poll_get_char(struct uart_port *port)
124 {
125 unsigned short status;
126 int c;
127
128 do {
129 status = sci_in(port, SCxSR);
130 if (status & SCxSR_ERRORS(port)) {
131 handle_error(port);
132 continue;
133 }
134 } while (!(status & SCxSR_RDxF(port)));
135
136 c = sci_in(port, SCxRDR);
137
138 /* Dummy read */
139 sci_in(port, SCxSR);
140 sci_out(port, SCxSR, SCxSR_RDxF_CLEAR(port));
141
142 return c;
143 }
144 #endif
145
146 static void sci_poll_put_char(struct uart_port *port, unsigned char c)
147 {
148 unsigned short status;
149
150 do {
151 status = sci_in(port, SCxSR);
152 } while (!(status & SCxSR_TDxE(port)));
153
154 sci_out(port, SCxTDR, c);
155 sci_out(port, SCxSR, SCxSR_TDxE_CLEAR(port) & ~SCxSR_TEND(port));
156 }
157 #endif /* CONFIG_CONSOLE_POLL || CONFIG_SERIAL_SH_SCI_CONSOLE */
158
159 #if defined(__H8300S__)
160 enum { sci_disable, sci_enable };
161
162 static void h8300_sci_config(struct uart_port *port, unsigned int ctrl)
163 {
164 volatile unsigned char *mstpcrl = (volatile unsigned char *)MSTPCRL;
165 int ch = (port->mapbase - SMR0) >> 3;
166 unsigned char mask = 1 << (ch+1);
167
168 if (ctrl == sci_disable)
169 *mstpcrl |= mask;
170 else
171 *mstpcrl &= ~mask;
172 }
173
174 static void h8300_sci_enable(struct uart_port *port)
175 {
176 h8300_sci_config(port, sci_enable);
177 }
178
179 static void h8300_sci_disable(struct uart_port *port)
180 {
181 h8300_sci_config(port, sci_disable);
182 }
183 #endif
184
185 #if defined(__H8300H__) || defined(__H8300S__)
186 static void sci_init_pins(struct uart_port *port, unsigned int cflag)
187 {
188 int ch = (port->mapbase - SMR0) >> 3;
189
190 /* set DDR regs */
191 H8300_GPIO_DDR(h8300_sci_pins[ch].port,
192 h8300_sci_pins[ch].rx,
193 H8300_GPIO_INPUT);
194 H8300_GPIO_DDR(h8300_sci_pins[ch].port,
195 h8300_sci_pins[ch].tx,
196 H8300_GPIO_OUTPUT);
197
198 /* tx mark output*/
199 H8300_SCI_DR(ch) |= h8300_sci_pins[ch].tx;
200 }
201 #elif defined(CONFIG_CPU_SUBTYPE_SH7710) || defined(CONFIG_CPU_SUBTYPE_SH7712)
202 static inline void sci_init_pins(struct uart_port *port, unsigned int cflag)
203 {
204 if (port->mapbase == 0xA4400000) {
205 __raw_writew(__raw_readw(PACR) & 0xffc0, PACR);
206 __raw_writew(__raw_readw(PBCR) & 0x0fff, PBCR);
207 } else if (port->mapbase == 0xA4410000)
208 __raw_writew(__raw_readw(PBCR) & 0xf003, PBCR);
209 }
210 #elif defined(CONFIG_CPU_SUBTYPE_SH7720) || defined(CONFIG_CPU_SUBTYPE_SH7721)
211 static inline void sci_init_pins(struct uart_port *port, unsigned int cflag)
212 {
213 unsigned short data;
214
215 if (cflag & CRTSCTS) {
216 /* enable RTS/CTS */
217 if (port->mapbase == 0xa4430000) { /* SCIF0 */
218 /* Clear PTCR bit 9-2; enable all scif pins but sck */
219 data = __raw_readw(PORT_PTCR);
220 __raw_writew((data & 0xfc03), PORT_PTCR);
221 } else if (port->mapbase == 0xa4438000) { /* SCIF1 */
222 /* Clear PVCR bit 9-2 */
223 data = __raw_readw(PORT_PVCR);
224 __raw_writew((data & 0xfc03), PORT_PVCR);
225 }
226 } else {
227 if (port->mapbase == 0xa4430000) { /* SCIF0 */
228 /* Clear PTCR bit 5-2; enable only tx and rx */
229 data = __raw_readw(PORT_PTCR);
230 __raw_writew((data & 0xffc3), PORT_PTCR);
231 } else if (port->mapbase == 0xa4438000) { /* SCIF1 */
232 /* Clear PVCR bit 5-2 */
233 data = __raw_readw(PORT_PVCR);
234 __raw_writew((data & 0xffc3), PORT_PVCR);
235 }
236 }
237 }
238 #elif defined(CONFIG_CPU_SH3)
239 /* For SH7705, SH7706, SH7707, SH7709, SH7709A, SH7729 */
240 static inline void sci_init_pins(struct uart_port *port, unsigned int cflag)
241 {
242 unsigned short data;
243
244 /* We need to set SCPCR to enable RTS/CTS */
245 data = __raw_readw(SCPCR);
246 /* Clear out SCP7MD1,0, SCP6MD1,0, SCP4MD1,0*/
247 __raw_writew(data & 0x0fcf, SCPCR);
248
249 if (!(cflag & CRTSCTS)) {
250 /* We need to set SCPCR to enable RTS/CTS */
251 data = __raw_readw(SCPCR);
252 /* Clear out SCP7MD1,0, SCP4MD1,0,
253 Set SCP6MD1,0 = {01} (output) */
254 __raw_writew((data & 0x0fcf) | 0x1000, SCPCR);
255
256 data = ctrl_inb(SCPDR);
257 /* Set /RTS2 (bit6) = 0 */
258 ctrl_outb(data & 0xbf, SCPDR);
259 }
260 }
261 #elif defined(CONFIG_CPU_SUBTYPE_SH7722)
262 static inline void sci_init_pins(struct uart_port *port, unsigned int cflag)
263 {
264 unsigned short data;
265
266 if (port->mapbase == 0xffe00000) {
267 data = __raw_readw(PSCR);
268 data &= ~0x03cf;
269 if (!(cflag & CRTSCTS))
270 data |= 0x0340;
271
272 __raw_writew(data, PSCR);
273 }
274 }
275 #elif defined(CONFIG_CPU_SUBTYPE_SH7757) || \
276 defined(CONFIG_CPU_SUBTYPE_SH7763) || \
277 defined(CONFIG_CPU_SUBTYPE_SH7780) || \
278 defined(CONFIG_CPU_SUBTYPE_SH7785) || \
279 defined(CONFIG_CPU_SUBTYPE_SH7786) || \
280 defined(CONFIG_CPU_SUBTYPE_SHX3)
281 static inline void sci_init_pins(struct uart_port *port, unsigned int cflag)
282 {
283 if (!(cflag & CRTSCTS))
284 __raw_writew(0x0080, SCSPTR0); /* Set RTS = 1 */
285 }
286 #elif defined(CONFIG_CPU_SH4) && !defined(CONFIG_CPU_SH4A)
287 static inline void sci_init_pins(struct uart_port *port, unsigned int cflag)
288 {
289 if (!(cflag & CRTSCTS))
290 __raw_writew(0x0080, SCSPTR2); /* Set RTS = 1 */
291 }
292 #else
293 static inline void sci_init_pins(struct uart_port *port, unsigned int cflag)
294 {
295 /* Nothing to do */
296 }
297 #endif
298
299 #if defined(CONFIG_CPU_SUBTYPE_SH7760) || \
300 defined(CONFIG_CPU_SUBTYPE_SH7780) || \
301 defined(CONFIG_CPU_SUBTYPE_SH7785) || \
302 defined(CONFIG_CPU_SUBTYPE_SH7786)
303 static inline int scif_txroom(struct uart_port *port)
304 {
305 return SCIF_TXROOM_MAX - (sci_in(port, SCTFDR) & 0xff);
306 }
307
308 static inline int scif_rxroom(struct uart_port *port)
309 {
310 return sci_in(port, SCRFDR) & 0xff;
311 }
312 #elif defined(CONFIG_CPU_SUBTYPE_SH7763)
313 static inline int scif_txroom(struct uart_port *port)
314 {
315 if ((port->mapbase == 0xffe00000) ||
316 (port->mapbase == 0xffe08000)) {
317 /* SCIF0/1*/
318 return SCIF_TXROOM_MAX - (sci_in(port, SCTFDR) & 0xff);
319 } else {
320 /* SCIF2 */
321 return SCIF2_TXROOM_MAX - (sci_in(port, SCFDR) >> 8);
322 }
323 }
324
325 static inline int scif_rxroom(struct uart_port *port)
326 {
327 if ((port->mapbase == 0xffe00000) ||
328 (port->mapbase == 0xffe08000)) {
329 /* SCIF0/1*/
330 return sci_in(port, SCRFDR) & 0xff;
331 } else {
332 /* SCIF2 */
333 return sci_in(port, SCFDR) & SCIF2_RFDC_MASK;
334 }
335 }
336 #else
337 static inline int scif_txroom(struct uart_port *port)
338 {
339 return SCIF_TXROOM_MAX - (sci_in(port, SCFDR) >> 8);
340 }
341
342 static inline int scif_rxroom(struct uart_port *port)
343 {
344 return sci_in(port, SCFDR) & SCIF_RFDC_MASK;
345 }
346 #endif
347
348 static inline int sci_txroom(struct uart_port *port)
349 {
350 return (sci_in(port, SCxSR) & SCI_TDRE) != 0;
351 }
352
353 static inline int sci_rxroom(struct uart_port *port)
354 {
355 return (sci_in(port, SCxSR) & SCxSR_RDxF(port)) != 0;
356 }
357
358 /* ********************************************************************** *
359 * the interrupt related routines *
360 * ********************************************************************** */
361
362 static void sci_transmit_chars(struct uart_port *port)
363 {
364 struct circ_buf *xmit = &port->state->xmit;
365 unsigned int stopped = uart_tx_stopped(port);
366 unsigned short status;
367 unsigned short ctrl;
368 int count;
369
370 status = sci_in(port, SCxSR);
371 if (!(status & SCxSR_TDxE(port))) {
372 ctrl = sci_in(port, SCSCR);
373 if (uart_circ_empty(xmit))
374 ctrl &= ~SCI_CTRL_FLAGS_TIE;
375 else
376 ctrl |= SCI_CTRL_FLAGS_TIE;
377 sci_out(port, SCSCR, ctrl);
378 return;
379 }
380
381 if (port->type == PORT_SCI)
382 count = sci_txroom(port);
383 else
384 count = scif_txroom(port);
385
386 do {
387 unsigned char c;
388
389 if (port->x_char) {
390 c = port->x_char;
391 port->x_char = 0;
392 } else if (!uart_circ_empty(xmit) && !stopped) {
393 c = xmit->buf[xmit->tail];
394 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
395 } else {
396 break;
397 }
398
399 sci_out(port, SCxTDR, c);
400
401 port->icount.tx++;
402 } while (--count > 0);
403
404 sci_out(port, SCxSR, SCxSR_TDxE_CLEAR(port));
405
406 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
407 uart_write_wakeup(port);
408 if (uart_circ_empty(xmit)) {
409 sci_stop_tx(port);
410 } else {
411 ctrl = sci_in(port, SCSCR);
412
413 if (port->type != PORT_SCI) {
414 sci_in(port, SCxSR); /* Dummy read */
415 sci_out(port, SCxSR, SCxSR_TDxE_CLEAR(port));
416 }
417
418 ctrl |= SCI_CTRL_FLAGS_TIE;
419 sci_out(port, SCSCR, ctrl);
420 }
421 }
422
423 /* On SH3, SCIF may read end-of-break as a space->mark char */
424 #define STEPFN(c) ({int __c = (c); (((__c-1)|(__c)) == -1); })
425
426 static inline void sci_receive_chars(struct uart_port *port)
427 {
428 struct sci_port *sci_port = to_sci_port(port);
429 struct tty_struct *tty = port->state->port.tty;
430 int i, count, copied = 0;
431 unsigned short status;
432 unsigned char flag;
433
434 status = sci_in(port, SCxSR);
435 if (!(status & SCxSR_RDxF(port)))
436 return;
437
438 while (1) {
439 if (port->type == PORT_SCI)
440 count = sci_rxroom(port);
441 else
442 count = scif_rxroom(port);
443
444 /* Don't copy more bytes than there is room for in the buffer */
445 count = tty_buffer_request_room(tty, count);
446
447 /* If for any reason we can't copy more data, we're done! */
448 if (count == 0)
449 break;
450
451 if (port->type == PORT_SCI) {
452 char c = sci_in(port, SCxRDR);
453 if (uart_handle_sysrq_char(port, c) ||
454 sci_port->break_flag)
455 count = 0;
456 else
457 tty_insert_flip_char(tty, c, TTY_NORMAL);
458 } else {
459 for (i = 0; i < count; i++) {
460 char c = sci_in(port, SCxRDR);
461 status = sci_in(port, SCxSR);
462 #if defined(CONFIG_CPU_SH3)
463 /* Skip "chars" during break */
464 if (sci_port->break_flag) {
465 if ((c == 0) &&
466 (status & SCxSR_FER(port))) {
467 count--; i--;
468 continue;
469 }
470
471 /* Nonzero => end-of-break */
472 dev_dbg(port->dev, "debounce<%02x>\n", c);
473 sci_port->break_flag = 0;
474
475 if (STEPFN(c)) {
476 count--; i--;
477 continue;
478 }
479 }
480 #endif /* CONFIG_CPU_SH3 */
481 if (uart_handle_sysrq_char(port, c)) {
482 count--; i--;
483 continue;
484 }
485
486 /* Store data and status */
487 if (status&SCxSR_FER(port)) {
488 flag = TTY_FRAME;
489 dev_notice(port->dev, "frame error\n");
490 } else if (status&SCxSR_PER(port)) {
491 flag = TTY_PARITY;
492 dev_notice(port->dev, "parity error\n");
493 } else
494 flag = TTY_NORMAL;
495
496 tty_insert_flip_char(tty, c, flag);
497 }
498 }
499
500 sci_in(port, SCxSR); /* dummy read */
501 sci_out(port, SCxSR, SCxSR_RDxF_CLEAR(port));
502
503 copied += count;
504 port->icount.rx += count;
505 }
506
507 if (copied) {
508 /* Tell the rest of the system the news. New characters! */
509 tty_flip_buffer_push(tty);
510 } else {
511 sci_in(port, SCxSR); /* dummy read */
512 sci_out(port, SCxSR, SCxSR_RDxF_CLEAR(port));
513 }
514 }
515
516 #define SCI_BREAK_JIFFIES (HZ/20)
517 /* The sci generates interrupts during the break,
518 * 1 per millisecond or so during the break period, for 9600 baud.
519 * So dont bother disabling interrupts.
520 * But dont want more than 1 break event.
521 * Use a kernel timer to periodically poll the rx line until
522 * the break is finished.
523 */
524 static void sci_schedule_break_timer(struct sci_port *port)
525 {
526 port->break_timer.expires = jiffies + SCI_BREAK_JIFFIES;
527 add_timer(&port->break_timer);
528 }
529 /* Ensure that two consecutive samples find the break over. */
530 static void sci_break_timer(unsigned long data)
531 {
532 struct sci_port *port = (struct sci_port *)data;
533
534 if (sci_rxd_in(&port->port) == 0) {
535 port->break_flag = 1;
536 sci_schedule_break_timer(port);
537 } else if (port->break_flag == 1) {
538 /* break is over. */
539 port->break_flag = 2;
540 sci_schedule_break_timer(port);
541 } else
542 port->break_flag = 0;
543 }
544
545 static inline int sci_handle_errors(struct uart_port *port)
546 {
547 int copied = 0;
548 unsigned short status = sci_in(port, SCxSR);
549 struct tty_struct *tty = port->state->port.tty;
550
551 if (status & SCxSR_ORER(port)) {
552 /* overrun error */
553 if (tty_insert_flip_char(tty, 0, TTY_OVERRUN))
554 copied++;
555
556 dev_notice(port->dev, "overrun error");
557 }
558
559 if (status & SCxSR_FER(port)) {
560 if (sci_rxd_in(port) == 0) {
561 /* Notify of BREAK */
562 struct sci_port *sci_port = to_sci_port(port);
563
564 if (!sci_port->break_flag) {
565 sci_port->break_flag = 1;
566 sci_schedule_break_timer(sci_port);
567
568 /* Do sysrq handling. */
569 if (uart_handle_break(port))
570 return 0;
571
572 dev_dbg(port->dev, "BREAK detected\n");
573
574 if (tty_insert_flip_char(tty, 0, TTY_BREAK))
575 copied++;
576 }
577
578 } else {
579 /* frame error */
580 if (tty_insert_flip_char(tty, 0, TTY_FRAME))
581 copied++;
582
583 dev_notice(port->dev, "frame error\n");
584 }
585 }
586
587 if (status & SCxSR_PER(port)) {
588 /* parity error */
589 if (tty_insert_flip_char(tty, 0, TTY_PARITY))
590 copied++;
591
592 dev_notice(port->dev, "parity error");
593 }
594
595 if (copied)
596 tty_flip_buffer_push(tty);
597
598 return copied;
599 }
600
601 static inline int sci_handle_fifo_overrun(struct uart_port *port)
602 {
603 struct tty_struct *tty = port->state->port.tty;
604 int copied = 0;
605
606 if (port->type != PORT_SCIF)
607 return 0;
608
609 if ((sci_in(port, SCLSR) & SCIF_ORER) != 0) {
610 sci_out(port, SCLSR, 0);
611
612 tty_insert_flip_char(tty, 0, TTY_OVERRUN);
613 tty_flip_buffer_push(tty);
614
615 dev_notice(port->dev, "overrun error\n");
616 copied++;
617 }
618
619 return copied;
620 }
621
622 static inline int sci_handle_breaks(struct uart_port *port)
623 {
624 int copied = 0;
625 unsigned short status = sci_in(port, SCxSR);
626 struct tty_struct *tty = port->state->port.tty;
627 struct sci_port *s = to_sci_port(port);
628
629 if (uart_handle_break(port))
630 return 0;
631
632 if (!s->break_flag && status & SCxSR_BRK(port)) {
633 #if defined(CONFIG_CPU_SH3)
634 /* Debounce break */
635 s->break_flag = 1;
636 #endif
637 /* Notify of BREAK */
638 if (tty_insert_flip_char(tty, 0, TTY_BREAK))
639 copied++;
640
641 dev_dbg(port->dev, "BREAK detected\n");
642 }
643
644 if (copied)
645 tty_flip_buffer_push(tty);
646
647 copied += sci_handle_fifo_overrun(port);
648
649 return copied;
650 }
651
652 static irqreturn_t sci_rx_interrupt(int irq, void *port)
653 {
654 /* I think sci_receive_chars has to be called irrespective
655 * of whether the I_IXOFF is set, otherwise, how is the interrupt
656 * to be disabled?
657 */
658 sci_receive_chars(port);
659
660 return IRQ_HANDLED;
661 }
662
663 static irqreturn_t sci_tx_interrupt(int irq, void *ptr)
664 {
665 struct uart_port *port = ptr;
666 unsigned long flags;
667
668 spin_lock_irqsave(&port->lock, flags);
669 sci_transmit_chars(port);
670 spin_unlock_irqrestore(&port->lock, flags);
671
672 return IRQ_HANDLED;
673 }
674
675 static irqreturn_t sci_er_interrupt(int irq, void *ptr)
676 {
677 struct uart_port *port = ptr;
678
679 /* Handle errors */
680 if (port->type == PORT_SCI) {
681 if (sci_handle_errors(port)) {
682 /* discard character in rx buffer */
683 sci_in(port, SCxSR);
684 sci_out(port, SCxSR, SCxSR_RDxF_CLEAR(port));
685 }
686 } else {
687 sci_handle_fifo_overrun(port);
688 sci_rx_interrupt(irq, ptr);
689 }
690
691 sci_out(port, SCxSR, SCxSR_ERROR_CLEAR(port));
692
693 /* Kick the transmission */
694 sci_tx_interrupt(irq, ptr);
695
696 return IRQ_HANDLED;
697 }
698
699 static irqreturn_t sci_br_interrupt(int irq, void *ptr)
700 {
701 struct uart_port *port = ptr;
702
703 /* Handle BREAKs */
704 sci_handle_breaks(port);
705 sci_out(port, SCxSR, SCxSR_BREAK_CLEAR(port));
706
707 return IRQ_HANDLED;
708 }
709
710 static irqreturn_t sci_mpxed_interrupt(int irq, void *ptr)
711 {
712 unsigned short ssr_status, scr_status, err_enabled;
713 struct uart_port *port = ptr;
714 irqreturn_t ret = IRQ_NONE;
715
716 ssr_status = sci_in(port, SCxSR);
717 scr_status = sci_in(port, SCSCR);
718 err_enabled = scr_status & (SCI_CTRL_FLAGS_REIE | SCI_CTRL_FLAGS_RIE);
719
720 /* Tx Interrupt */
721 if ((ssr_status & SCxSR_TDxE(port)) && (scr_status & SCI_CTRL_FLAGS_TIE))
722 ret = sci_tx_interrupt(irq, ptr);
723 /* Rx Interrupt */
724 if ((ssr_status & SCxSR_RDxF(port)) && (scr_status & SCI_CTRL_FLAGS_RIE))
725 ret = sci_rx_interrupt(irq, ptr);
726 /* Error Interrupt */
727 if ((ssr_status & SCxSR_ERRORS(port)) && err_enabled)
728 ret = sci_er_interrupt(irq, ptr);
729 /* Break Interrupt */
730 if ((ssr_status & SCxSR_BRK(port)) && err_enabled)
731 ret = sci_br_interrupt(irq, ptr);
732
733 return ret;
734 }
735
736 #ifdef CONFIG_HAVE_CLK
737 /*
738 * Here we define a transistion notifier so that we can update all of our
739 * ports' baud rate when the peripheral clock changes.
740 */
741 static int sci_notifier(struct notifier_block *self,
742 unsigned long phase, void *p)
743 {
744 struct sh_sci_priv *priv = container_of(self,
745 struct sh_sci_priv, clk_nb);
746 struct sci_port *sci_port;
747 unsigned long flags;
748
749 if ((phase == CPUFREQ_POSTCHANGE) ||
750 (phase == CPUFREQ_RESUMECHANGE)) {
751 spin_lock_irqsave(&priv->lock, flags);
752 list_for_each_entry(sci_port, &priv->ports, node)
753 sci_port->port.uartclk = clk_get_rate(sci_port->dclk);
754
755 spin_unlock_irqrestore(&priv->lock, flags);
756 }
757
758 return NOTIFY_OK;
759 }
760
761 static void sci_clk_enable(struct uart_port *port)
762 {
763 struct sci_port *sci_port = to_sci_port(port);
764
765 clk_enable(sci_port->dclk);
766 sci_port->port.uartclk = clk_get_rate(sci_port->dclk);
767
768 if (sci_port->iclk)
769 clk_enable(sci_port->iclk);
770 }
771
772 static void sci_clk_disable(struct uart_port *port)
773 {
774 struct sci_port *sci_port = to_sci_port(port);
775
776 if (sci_port->iclk)
777 clk_disable(sci_port->iclk);
778
779 clk_disable(sci_port->dclk);
780 }
781 #endif
782
783 static int sci_request_irq(struct sci_port *port)
784 {
785 int i;
786 irqreturn_t (*handlers[4])(int irq, void *ptr) = {
787 sci_er_interrupt, sci_rx_interrupt, sci_tx_interrupt,
788 sci_br_interrupt,
789 };
790 const char *desc[] = { "SCI Receive Error", "SCI Receive Data Full",
791 "SCI Transmit Data Empty", "SCI Break" };
792
793 if (port->irqs[0] == port->irqs[1]) {
794 if (unlikely(!port->irqs[0]))
795 return -ENODEV;
796
797 if (request_irq(port->irqs[0], sci_mpxed_interrupt,
798 IRQF_DISABLED, "sci", port)) {
799 dev_err(port->port.dev, "Can't allocate IRQ\n");
800 return -ENODEV;
801 }
802 } else {
803 for (i = 0; i < ARRAY_SIZE(handlers); i++) {
804 if (unlikely(!port->irqs[i]))
805 continue;
806
807 if (request_irq(port->irqs[i], handlers[i],
808 IRQF_DISABLED, desc[i], port)) {
809 dev_err(port->port.dev, "Can't allocate IRQ\n");
810 return -ENODEV;
811 }
812 }
813 }
814
815 return 0;
816 }
817
818 static void sci_free_irq(struct sci_port *port)
819 {
820 int i;
821
822 if (port->irqs[0] == port->irqs[1])
823 free_irq(port->irqs[0], port);
824 else {
825 for (i = 0; i < ARRAY_SIZE(port->irqs); i++) {
826 if (!port->irqs[i])
827 continue;
828
829 free_irq(port->irqs[i], port);
830 }
831 }
832 }
833
834 static unsigned int sci_tx_empty(struct uart_port *port)
835 {
836 /* Can't detect */
837 return TIOCSER_TEMT;
838 }
839
840 static void sci_set_mctrl(struct uart_port *port, unsigned int mctrl)
841 {
842 /* This routine is used for seting signals of: DTR, DCD, CTS/RTS */
843 /* We use SCIF's hardware for CTS/RTS, so don't need any for that. */
844 /* If you have signals for DTR and DCD, please implement here. */
845 }
846
847 static unsigned int sci_get_mctrl(struct uart_port *port)
848 {
849 /* This routine is used for geting signals of: DTR, DCD, DSR, RI,
850 and CTS/RTS */
851
852 return TIOCM_DTR | TIOCM_RTS | TIOCM_DSR;
853 }
854
855 static void sci_start_tx(struct uart_port *port)
856 {
857 unsigned short ctrl;
858
859 /* Set TIE (Transmit Interrupt Enable) bit in SCSCR */
860 ctrl = sci_in(port, SCSCR);
861 ctrl |= SCI_CTRL_FLAGS_TIE;
862 sci_out(port, SCSCR, ctrl);
863 }
864
865 static void sci_stop_tx(struct uart_port *port)
866 {
867 unsigned short ctrl;
868
869 /* Clear TIE (Transmit Interrupt Enable) bit in SCSCR */
870 ctrl = sci_in(port, SCSCR);
871 ctrl &= ~SCI_CTRL_FLAGS_TIE;
872 sci_out(port, SCSCR, ctrl);
873 }
874
875 static void sci_start_rx(struct uart_port *port, unsigned int tty_start)
876 {
877 unsigned short ctrl;
878
879 /* Set RIE (Receive Interrupt Enable) bit in SCSCR */
880 ctrl = sci_in(port, SCSCR);
881 ctrl |= SCI_CTRL_FLAGS_RIE | SCI_CTRL_FLAGS_REIE;
882 sci_out(port, SCSCR, ctrl);
883 }
884
885 static void sci_stop_rx(struct uart_port *port)
886 {
887 unsigned short ctrl;
888
889 /* Clear RIE (Receive Interrupt Enable) bit in SCSCR */
890 ctrl = sci_in(port, SCSCR);
891 ctrl &= ~(SCI_CTRL_FLAGS_RIE | SCI_CTRL_FLAGS_REIE);
892 sci_out(port, SCSCR, ctrl);
893 }
894
895 static void sci_enable_ms(struct uart_port *port)
896 {
897 /* Nothing here yet .. */
898 }
899
900 static void sci_break_ctl(struct uart_port *port, int break_state)
901 {
902 /* Nothing here yet .. */
903 }
904
905 static int sci_startup(struct uart_port *port)
906 {
907 struct sci_port *s = to_sci_port(port);
908
909 if (s->enable)
910 s->enable(port);
911
912 sci_request_irq(s);
913 sci_start_tx(port);
914 sci_start_rx(port, 1);
915
916 return 0;
917 }
918
919 static void sci_shutdown(struct uart_port *port)
920 {
921 struct sci_port *s = to_sci_port(port);
922
923 sci_stop_rx(port);
924 sci_stop_tx(port);
925 sci_free_irq(s);
926
927 if (s->disable)
928 s->disable(port);
929 }
930
931 static void sci_set_termios(struct uart_port *port, struct ktermios *termios,
932 struct ktermios *old)
933 {
934 unsigned int status, baud, smr_val;
935 int t = -1;
936
937 baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk/16);
938 if (likely(baud))
939 t = SCBRR_VALUE(baud, port->uartclk);
940
941 do {
942 status = sci_in(port, SCxSR);
943 } while (!(status & SCxSR_TEND(port)));
944
945 sci_out(port, SCSCR, 0x00); /* TE=0, RE=0, CKE1=0 */
946
947 if (port->type != PORT_SCI)
948 sci_out(port, SCFCR, SCFCR_RFRST | SCFCR_TFRST);
949
950 smr_val = sci_in(port, SCSMR) & 3;
951 if ((termios->c_cflag & CSIZE) == CS7)
952 smr_val |= 0x40;
953 if (termios->c_cflag & PARENB)
954 smr_val |= 0x20;
955 if (termios->c_cflag & PARODD)
956 smr_val |= 0x30;
957 if (termios->c_cflag & CSTOPB)
958 smr_val |= 0x08;
959
960 uart_update_timeout(port, termios->c_cflag, baud);
961
962 sci_out(port, SCSMR, smr_val);
963
964 if (t > 0) {
965 if (t >= 256) {
966 sci_out(port, SCSMR, (sci_in(port, SCSMR) & ~3) | 1);
967 t >>= 2;
968 } else
969 sci_out(port, SCSMR, sci_in(port, SCSMR) & ~3);
970
971 sci_out(port, SCBRR, t);
972 udelay((1000000+(baud-1)) / baud); /* Wait one bit interval */
973 }
974
975 sci_init_pins(port, termios->c_cflag);
976 sci_out(port, SCFCR, (termios->c_cflag & CRTSCTS) ? SCFCR_MCE : 0);
977
978 sci_out(port, SCSCR, SCSCR_INIT(port));
979
980 if ((termios->c_cflag & CREAD) != 0)
981 sci_start_rx(port, 0);
982 }
983
984 static const char *sci_type(struct uart_port *port)
985 {
986 switch (port->type) {
987 case PORT_IRDA:
988 return "irda";
989 case PORT_SCI:
990 return "sci";
991 case PORT_SCIF:
992 return "scif";
993 case PORT_SCIFA:
994 return "scifa";
995 }
996
997 return NULL;
998 }
999
1000 static void sci_release_port(struct uart_port *port)
1001 {
1002 /* Nothing here yet .. */
1003 }
1004
1005 static int sci_request_port(struct uart_port *port)
1006 {
1007 /* Nothing here yet .. */
1008 return 0;
1009 }
1010
1011 static void sci_config_port(struct uart_port *port, int flags)
1012 {
1013 struct sci_port *s = to_sci_port(port);
1014
1015 port->type = s->type;
1016
1017 if (port->membase)
1018 return;
1019
1020 if (port->flags & UPF_IOREMAP) {
1021 port->membase = ioremap_nocache(port->mapbase, 0x40);
1022
1023 if (IS_ERR(port->membase))
1024 dev_err(port->dev, "can't remap port#%d\n", port->line);
1025 } else {
1026 /*
1027 * For the simple (and majority of) cases where we don't
1028 * need to do any remapping, just cast the cookie
1029 * directly.
1030 */
1031 port->membase = (void __iomem *)port->mapbase;
1032 }
1033 }
1034
1035 static int sci_verify_port(struct uart_port *port, struct serial_struct *ser)
1036 {
1037 struct sci_port *s = to_sci_port(port);
1038
1039 if (ser->irq != s->irqs[SCIx_TXI_IRQ] || ser->irq > nr_irqs)
1040 return -EINVAL;
1041 if (ser->baud_base < 2400)
1042 /* No paper tape reader for Mitch.. */
1043 return -EINVAL;
1044
1045 return 0;
1046 }
1047
1048 static struct uart_ops sci_uart_ops = {
1049 .tx_empty = sci_tx_empty,
1050 .set_mctrl = sci_set_mctrl,
1051 .get_mctrl = sci_get_mctrl,
1052 .start_tx = sci_start_tx,
1053 .stop_tx = sci_stop_tx,
1054 .stop_rx = sci_stop_rx,
1055 .enable_ms = sci_enable_ms,
1056 .break_ctl = sci_break_ctl,
1057 .startup = sci_startup,
1058 .shutdown = sci_shutdown,
1059 .set_termios = sci_set_termios,
1060 .type = sci_type,
1061 .release_port = sci_release_port,
1062 .request_port = sci_request_port,
1063 .config_port = sci_config_port,
1064 .verify_port = sci_verify_port,
1065 #ifdef CONFIG_CONSOLE_POLL
1066 .poll_get_char = sci_poll_get_char,
1067 .poll_put_char = sci_poll_put_char,
1068 #endif
1069 };
1070
1071 static void __devinit sci_init_single(struct platform_device *dev,
1072 struct sci_port *sci_port,
1073 unsigned int index,
1074 struct plat_sci_port *p)
1075 {
1076 sci_port->port.ops = &sci_uart_ops;
1077 sci_port->port.iotype = UPIO_MEM;
1078 sci_port->port.line = index;
1079 sci_port->port.fifosize = 1;
1080
1081 #if defined(__H8300H__) || defined(__H8300S__)
1082 #ifdef __H8300S__
1083 sci_port->enable = h8300_sci_enable;
1084 sci_port->disable = h8300_sci_disable;
1085 #endif
1086 sci_port->port.uartclk = CONFIG_CPU_CLOCK;
1087 #elif defined(CONFIG_HAVE_CLK)
1088 sci_port->iclk = p->clk ? clk_get(&dev->dev, p->clk) : NULL;
1089 sci_port->dclk = clk_get(&dev->dev, "peripheral_clk");
1090 sci_port->enable = sci_clk_enable;
1091 sci_port->disable = sci_clk_disable;
1092 #else
1093 #error "Need a valid uartclk"
1094 #endif
1095
1096 sci_port->break_timer.data = (unsigned long)sci_port;
1097 sci_port->break_timer.function = sci_break_timer;
1098 init_timer(&sci_port->break_timer);
1099
1100 sci_port->port.mapbase = p->mapbase;
1101 sci_port->port.membase = p->membase;
1102
1103 sci_port->port.irq = p->irqs[SCIx_TXI_IRQ];
1104 sci_port->port.flags = p->flags;
1105 sci_port->port.dev = &dev->dev;
1106 sci_port->type = sci_port->port.type = p->type;
1107
1108 memcpy(&sci_port->irqs, &p->irqs, sizeof(p->irqs));
1109
1110 }
1111
1112 #ifdef CONFIG_SERIAL_SH_SCI_CONSOLE
1113 static struct tty_driver *serial_console_device(struct console *co, int *index)
1114 {
1115 struct uart_driver *p = &sci_uart_driver;
1116 *index = co->index;
1117 return p->tty_driver;
1118 }
1119
1120 static void serial_console_putchar(struct uart_port *port, int ch)
1121 {
1122 sci_poll_put_char(port, ch);
1123 }
1124
1125 /*
1126 * Print a string to the serial port trying not to disturb
1127 * any possible real use of the port...
1128 */
1129 static void serial_console_write(struct console *co, const char *s,
1130 unsigned count)
1131 {
1132 struct uart_port *port = co->data;
1133 struct sci_port *sci_port = to_sci_port(port);
1134 unsigned short bits;
1135
1136 if (sci_port->enable)
1137 sci_port->enable(port);
1138
1139 uart_console_write(port, s, count, serial_console_putchar);
1140
1141 /* wait until fifo is empty and last bit has been transmitted */
1142 bits = SCxSR_TDxE(port) | SCxSR_TEND(port);
1143 while ((sci_in(port, SCxSR) & bits) != bits)
1144 cpu_relax();
1145
1146 if (sci_port->disable)
1147 sci_port->disable(port);
1148 }
1149
1150 static int __init serial_console_setup(struct console *co, char *options)
1151 {
1152 struct sci_port *sci_port;
1153 struct uart_port *port;
1154 int baud = 115200;
1155 int bits = 8;
1156 int parity = 'n';
1157 int flow = 'n';
1158 int ret;
1159
1160 /*
1161 * Check whether an invalid uart number has been specified, and
1162 * if so, search for the first available port that does have
1163 * console support.
1164 */
1165 if (co->index >= SCI_NPORTS)
1166 co->index = 0;
1167
1168 sci_port = &sci_ports[co->index];
1169 port = &sci_port->port;
1170 co->data = port;
1171
1172 /*
1173 * Also need to check port->type, we don't actually have any
1174 * UPIO_PORT ports, but uart_report_port() handily misreports
1175 * it anyways if we don't have a port available by the time this is
1176 * called.
1177 */
1178 if (!port->type)
1179 return -ENODEV;
1180
1181 sci_config_port(port, 0);
1182
1183 if (sci_port->enable)
1184 sci_port->enable(port);
1185
1186 if (options)
1187 uart_parse_options(options, &baud, &parity, &bits, &flow);
1188
1189 ret = uart_set_options(port, co, baud, parity, bits, flow);
1190 #if defined(__H8300H__) || defined(__H8300S__)
1191 /* disable rx interrupt */
1192 if (ret == 0)
1193 sci_stop_rx(port);
1194 #endif
1195 /* TODO: disable clock */
1196 return ret;
1197 }
1198
1199 static struct console serial_console = {
1200 .name = "ttySC",
1201 .device = serial_console_device,
1202 .write = serial_console_write,
1203 .setup = serial_console_setup,
1204 .flags = CON_PRINTBUFFER,
1205 .index = -1,
1206 };
1207
1208 static int __init sci_console_init(void)
1209 {
1210 register_console(&serial_console);
1211 return 0;
1212 }
1213 console_initcall(sci_console_init);
1214 #endif /* CONFIG_SERIAL_SH_SCI_CONSOLE */
1215
1216 #if defined(CONFIG_SERIAL_SH_SCI_CONSOLE)
1217 #define SCI_CONSOLE (&serial_console)
1218 #else
1219 #define SCI_CONSOLE 0
1220 #endif
1221
1222 static char banner[] __initdata =
1223 KERN_INFO "SuperH SCI(F) driver initialized\n";
1224
1225 static struct uart_driver sci_uart_driver = {
1226 .owner = THIS_MODULE,
1227 .driver_name = "sci",
1228 .dev_name = "ttySC",
1229 .major = SCI_MAJOR,
1230 .minor = SCI_MINOR_START,
1231 .nr = SCI_NPORTS,
1232 .cons = SCI_CONSOLE,
1233 };
1234
1235
1236 static int sci_remove(struct platform_device *dev)
1237 {
1238 struct sh_sci_priv *priv = platform_get_drvdata(dev);
1239 struct sci_port *p;
1240 unsigned long flags;
1241
1242 #ifdef CONFIG_HAVE_CLK
1243 cpufreq_unregister_notifier(&priv->clk_nb, CPUFREQ_TRANSITION_NOTIFIER);
1244 #endif
1245
1246 spin_lock_irqsave(&priv->lock, flags);
1247 list_for_each_entry(p, &priv->ports, node)
1248 uart_remove_one_port(&sci_uart_driver, &p->port);
1249
1250 spin_unlock_irqrestore(&priv->lock, flags);
1251
1252 kfree(priv);
1253 return 0;
1254 }
1255
1256 static int __devinit sci_probe_single(struct platform_device *dev,
1257 unsigned int index,
1258 struct plat_sci_port *p,
1259 struct sci_port *sciport)
1260 {
1261 struct sh_sci_priv *priv = platform_get_drvdata(dev);
1262 unsigned long flags;
1263 int ret;
1264
1265 /* Sanity check */
1266 if (unlikely(index >= SCI_NPORTS)) {
1267 dev_notice(&dev->dev, "Attempting to register port "
1268 "%d when only %d are available.\n",
1269 index+1, SCI_NPORTS);
1270 dev_notice(&dev->dev, "Consider bumping "
1271 "CONFIG_SERIAL_SH_SCI_NR_UARTS!\n");
1272 return 0;
1273 }
1274
1275 sci_init_single(dev, sciport, index, p);
1276
1277 ret = uart_add_one_port(&sci_uart_driver, &sciport->port);
1278 if (ret)
1279 return ret;
1280
1281 INIT_LIST_HEAD(&sciport->node);
1282
1283 spin_lock_irqsave(&priv->lock, flags);
1284 list_add(&sciport->node, &priv->ports);
1285 spin_unlock_irqrestore(&priv->lock, flags);
1286
1287 return 0;
1288 }
1289
1290 /*
1291 * Register a set of serial devices attached to a platform device. The
1292 * list is terminated with a zero flags entry, which means we expect
1293 * all entries to have at least UPF_BOOT_AUTOCONF set. Platforms that need
1294 * remapping (such as sh64) should also set UPF_IOREMAP.
1295 */
1296 static int __devinit sci_probe(struct platform_device *dev)
1297 {
1298 struct plat_sci_port *p = dev->dev.platform_data;
1299 struct sh_sci_priv *priv;
1300 int i, ret = -EINVAL;
1301
1302 priv = kzalloc(sizeof(*priv), GFP_KERNEL);
1303 if (!priv)
1304 return -ENOMEM;
1305
1306 INIT_LIST_HEAD(&priv->ports);
1307 spin_lock_init(&priv->lock);
1308 platform_set_drvdata(dev, priv);
1309
1310 #ifdef CONFIG_HAVE_CLK
1311 priv->clk_nb.notifier_call = sci_notifier;
1312 cpufreq_register_notifier(&priv->clk_nb, CPUFREQ_TRANSITION_NOTIFIER);
1313 #endif
1314
1315 if (dev->id != -1) {
1316 ret = sci_probe_single(dev, dev->id, p, &sci_ports[dev->id]);
1317 if (ret)
1318 goto err_unreg;
1319 } else {
1320 for (i = 0; p && p->flags != 0; p++, i++) {
1321 ret = sci_probe_single(dev, i, p, &sci_ports[i]);
1322 if (ret)
1323 goto err_unreg;
1324 }
1325 }
1326
1327 #ifdef CONFIG_SH_STANDARD_BIOS
1328 sh_bios_gdb_detach();
1329 #endif
1330
1331 return 0;
1332
1333 err_unreg:
1334 sci_remove(dev);
1335 return ret;
1336 }
1337
1338 static int sci_suspend(struct device *dev)
1339 {
1340 struct sh_sci_priv *priv = dev_get_drvdata(dev);
1341 struct sci_port *p;
1342 unsigned long flags;
1343
1344 spin_lock_irqsave(&priv->lock, flags);
1345 list_for_each_entry(p, &priv->ports, node)
1346 uart_suspend_port(&sci_uart_driver, &p->port);
1347 spin_unlock_irqrestore(&priv->lock, flags);
1348
1349 return 0;
1350 }
1351
1352 static int sci_resume(struct device *dev)
1353 {
1354 struct sh_sci_priv *priv = dev_get_drvdata(dev);
1355 struct sci_port *p;
1356 unsigned long flags;
1357
1358 spin_lock_irqsave(&priv->lock, flags);
1359 list_for_each_entry(p, &priv->ports, node)
1360 uart_resume_port(&sci_uart_driver, &p->port);
1361 spin_unlock_irqrestore(&priv->lock, flags);
1362
1363 return 0;
1364 }
1365
1366 static struct dev_pm_ops sci_dev_pm_ops = {
1367 .suspend = sci_suspend,
1368 .resume = sci_resume,
1369 };
1370
1371 static struct platform_driver sci_driver = {
1372 .probe = sci_probe,
1373 .remove = __devexit_p(sci_remove),
1374 .driver = {
1375 .name = "sh-sci",
1376 .owner = THIS_MODULE,
1377 .pm = &sci_dev_pm_ops,
1378 },
1379 };
1380
1381 static int __init sci_init(void)
1382 {
1383 int ret;
1384
1385 printk(banner);
1386
1387 ret = uart_register_driver(&sci_uart_driver);
1388 if (likely(ret == 0)) {
1389 ret = platform_driver_register(&sci_driver);
1390 if (unlikely(ret))
1391 uart_unregister_driver(&sci_uart_driver);
1392 }
1393
1394 return ret;
1395 }
1396
1397 static void __exit sci_exit(void)
1398 {
1399 platform_driver_unregister(&sci_driver);
1400 uart_unregister_driver(&sci_uart_driver);
1401 }
1402
1403 module_init(sci_init);
1404 module_exit(sci_exit);
1405
1406 MODULE_LICENSE("GPL");
1407 MODULE_ALIAS("platform:sh-sci");
Support for the Chinese Samsung S3C2440 based development boards