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x86, rwsem: Minor cleanups
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / drivers / serial / sh-sci.c
blob5f90fcd7d107573312bbd44ab7be8839ab61b567
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 #include <linux/dmaengine.h>
52 #include <linux/scatterlist.h>
53 #include <linux/slab.h>
54
55 #ifdef CONFIG_SUPERH
56 #include <asm/sh_bios.h>
57 #endif
58
59 #ifdef CONFIG_H8300
60 #include <asm/gpio.h>
61 #endif
62
63 #include "sh-sci.h"
64
65 struct sci_port {
66 struct uart_port port;
67
68 /* Port type */
69 unsigned int type;
70
71 /* Port IRQs: ERI, RXI, TXI, BRI (optional) */
72 unsigned int irqs[SCIx_NR_IRQS];
73
74 /* Port enable callback */
75 void (*enable)(struct uart_port *port);
76
77 /* Port disable callback */
78 void (*disable)(struct uart_port *port);
79
80 /* Break timer */
81 struct timer_list break_timer;
82 int break_flag;
83
84 /* Interface clock */
85 struct clk *iclk;
86 /* Function clock */
87 struct clk *fclk;
88
89 struct list_head node;
90 struct dma_chan *chan_tx;
91 struct dma_chan *chan_rx;
92 #ifdef CONFIG_SERIAL_SH_SCI_DMA
93 struct device *dma_dev;
94 unsigned int slave_tx;
95 unsigned int slave_rx;
96 struct dma_async_tx_descriptor *desc_tx;
97 struct dma_async_tx_descriptor *desc_rx[2];
98 dma_cookie_t cookie_tx;
99 dma_cookie_t cookie_rx[2];
100 dma_cookie_t active_rx;
101 struct scatterlist sg_tx;
102 unsigned int sg_len_tx;
103 struct scatterlist sg_rx[2];
104 size_t buf_len_rx;
105 struct sh_dmae_slave param_tx;
106 struct sh_dmae_slave param_rx;
107 struct work_struct work_tx;
108 struct work_struct work_rx;
109 struct timer_list rx_timer;
110 unsigned int rx_timeout;
111 #endif
112 };
113
114 struct sh_sci_priv {
115 spinlock_t lock;
116 struct list_head ports;
117 struct notifier_block clk_nb;
118 };
119
120 /* Function prototypes */
121 static void sci_stop_tx(struct uart_port *port);
122
123 #define SCI_NPORTS CONFIG_SERIAL_SH_SCI_NR_UARTS
124
125 static struct sci_port sci_ports[SCI_NPORTS];
126 static struct uart_driver sci_uart_driver;
127
128 static inline struct sci_port *
129 to_sci_port(struct uart_port *uart)
130 {
131 return container_of(uart, struct sci_port, port);
132 }
133
134 #if defined(CONFIG_CONSOLE_POLL) || defined(CONFIG_SERIAL_SH_SCI_CONSOLE)
135
136 #ifdef CONFIG_CONSOLE_POLL
137 static inline void handle_error(struct uart_port *port)
138 {
139 /* Clear error flags */
140 sci_out(port, SCxSR, SCxSR_ERROR_CLEAR(port));
141 }
142
143 static int sci_poll_get_char(struct uart_port *port)
144 {
145 unsigned short status;
146 int c;
147
148 do {
149 status = sci_in(port, SCxSR);
150 if (status & SCxSR_ERRORS(port)) {
151 handle_error(port);
152 continue;
153 }
154 break;
155 } while (1);
156
157 if (!(status & SCxSR_RDxF(port)))
158 return NO_POLL_CHAR;
159
160 c = sci_in(port, SCxRDR);
161
162 /* Dummy read */
163 sci_in(port, SCxSR);
164 sci_out(port, SCxSR, SCxSR_RDxF_CLEAR(port));
165
166 return c;
167 }
168 #endif
169
170 static void sci_poll_put_char(struct uart_port *port, unsigned char c)
171 {
172 unsigned short status;
173
174 do {
175 status = sci_in(port, SCxSR);
176 } while (!(status & SCxSR_TDxE(port)));
177
178 sci_out(port, SCxTDR, c);
179 sci_out(port, SCxSR, SCxSR_TDxE_CLEAR(port) & ~SCxSR_TEND(port));
180 }
181 #endif /* CONFIG_CONSOLE_POLL || CONFIG_SERIAL_SH_SCI_CONSOLE */
182
183 #if defined(__H8300H__) || defined(__H8300S__)
184 static void sci_init_pins(struct uart_port *port, unsigned int cflag)
185 {
186 int ch = (port->mapbase - SMR0) >> 3;
187
188 /* set DDR regs */
189 H8300_GPIO_DDR(h8300_sci_pins[ch].port,
190 h8300_sci_pins[ch].rx,
191 H8300_GPIO_INPUT);
192 H8300_GPIO_DDR(h8300_sci_pins[ch].port,
193 h8300_sci_pins[ch].tx,
194 H8300_GPIO_OUTPUT);
195
196 /* tx mark output*/
197 H8300_SCI_DR(ch) |= h8300_sci_pins[ch].tx;
198 }
199 #elif defined(CONFIG_CPU_SUBTYPE_SH7710) || defined(CONFIG_CPU_SUBTYPE_SH7712)
200 static inline void sci_init_pins(struct uart_port *port, unsigned int cflag)
201 {
202 if (port->mapbase == 0xA4400000) {
203 __raw_writew(__raw_readw(PACR) & 0xffc0, PACR);
204 __raw_writew(__raw_readw(PBCR) & 0x0fff, PBCR);
205 } else if (port->mapbase == 0xA4410000)
206 __raw_writew(__raw_readw(PBCR) & 0xf003, PBCR);
207 }
208 #elif defined(CONFIG_CPU_SUBTYPE_SH7720) || defined(CONFIG_CPU_SUBTYPE_SH7721)
209 static inline void sci_init_pins(struct uart_port *port, unsigned int cflag)
210 {
211 unsigned short data;
212
213 if (cflag & CRTSCTS) {
214 /* enable RTS/CTS */
215 if (port->mapbase == 0xa4430000) { /* SCIF0 */
216 /* Clear PTCR bit 9-2; enable all scif pins but sck */
217 data = __raw_readw(PORT_PTCR);
218 __raw_writew((data & 0xfc03), PORT_PTCR);
219 } else if (port->mapbase == 0xa4438000) { /* SCIF1 */
220 /* Clear PVCR bit 9-2 */
221 data = __raw_readw(PORT_PVCR);
222 __raw_writew((data & 0xfc03), PORT_PVCR);
223 }
224 } else {
225 if (port->mapbase == 0xa4430000) { /* SCIF0 */
226 /* Clear PTCR bit 5-2; enable only tx and rx */
227 data = __raw_readw(PORT_PTCR);
228 __raw_writew((data & 0xffc3), PORT_PTCR);
229 } else if (port->mapbase == 0xa4438000) { /* SCIF1 */
230 /* Clear PVCR bit 5-2 */
231 data = __raw_readw(PORT_PVCR);
232 __raw_writew((data & 0xffc3), PORT_PVCR);
233 }
234 }
235 }
236 #elif defined(CONFIG_CPU_SH3)
237 /* For SH7705, SH7706, SH7707, SH7709, SH7709A, SH7729 */
238 static inline void sci_init_pins(struct uart_port *port, unsigned int cflag)
239 {
240 unsigned short data;
241
242 /* We need to set SCPCR to enable RTS/CTS */
243 data = __raw_readw(SCPCR);
244 /* Clear out SCP7MD1,0, SCP6MD1,0, SCP4MD1,0*/
245 __raw_writew(data & 0x0fcf, SCPCR);
246
247 if (!(cflag & CRTSCTS)) {
248 /* We need to set SCPCR to enable RTS/CTS */
249 data = __raw_readw(SCPCR);
250 /* Clear out SCP7MD1,0, SCP4MD1,0,
251 Set SCP6MD1,0 = {01} (output) */
252 __raw_writew((data & 0x0fcf) | 0x1000, SCPCR);
253
254 data = __raw_readb(SCPDR);
255 /* Set /RTS2 (bit6) = 0 */
256 __raw_writeb(data & 0xbf, SCPDR);
257 }
258 }
259 #elif defined(CONFIG_CPU_SUBTYPE_SH7722)
260 static inline void sci_init_pins(struct uart_port *port, unsigned int cflag)
261 {
262 unsigned short data;
263
264 if (port->mapbase == 0xffe00000) {
265 data = __raw_readw(PSCR);
266 data &= ~0x03cf;
267 if (!(cflag & CRTSCTS))
268 data |= 0x0340;
269
270 __raw_writew(data, PSCR);
271 }
272 }
273 #elif defined(CONFIG_CPU_SUBTYPE_SH7757) || \
274 defined(CONFIG_CPU_SUBTYPE_SH7763) || \
275 defined(CONFIG_CPU_SUBTYPE_SH7780) || \
276 defined(CONFIG_CPU_SUBTYPE_SH7785) || \
277 defined(CONFIG_CPU_SUBTYPE_SH7786) || \
278 defined(CONFIG_CPU_SUBTYPE_SHX3)
279 static inline void sci_init_pins(struct uart_port *port, unsigned int cflag)
280 {
281 if (!(cflag & CRTSCTS))
282 __raw_writew(0x0080, SCSPTR0); /* Set RTS = 1 */
283 }
284 #elif defined(CONFIG_CPU_SH4) && !defined(CONFIG_CPU_SH4A)
285 static inline void sci_init_pins(struct uart_port *port, unsigned int cflag)
286 {
287 if (!(cflag & CRTSCTS))
288 __raw_writew(0x0080, SCSPTR2); /* Set RTS = 1 */
289 }
290 #else
291 static inline void sci_init_pins(struct uart_port *port, unsigned int cflag)
292 {
293 /* Nothing to do */
294 }
295 #endif
296
297 #if defined(CONFIG_CPU_SUBTYPE_SH7760) || \
298 defined(CONFIG_CPU_SUBTYPE_SH7780) || \
299 defined(CONFIG_CPU_SUBTYPE_SH7785) || \
300 defined(CONFIG_CPU_SUBTYPE_SH7786)
301 static int scif_txfill(struct uart_port *port)
302 {
303 return sci_in(port, SCTFDR) & 0xff;
304 }
305
306 static int scif_txroom(struct uart_port *port)
307 {
308 return SCIF_TXROOM_MAX - scif_txfill(port);
309 }
310
311 static int scif_rxfill(struct uart_port *port)
312 {
313 return sci_in(port, SCRFDR) & 0xff;
314 }
315 #elif defined(CONFIG_CPU_SUBTYPE_SH7763)
316 static int scif_txfill(struct uart_port *port)
317 {
318 if (port->mapbase == 0xffe00000 ||
319 port->mapbase == 0xffe08000)
320 /* SCIF0/1*/
321 return sci_in(port, SCTFDR) & 0xff;
322 else
323 /* SCIF2 */
324 return sci_in(port, SCFDR) >> 8;
325 }
326
327 static int scif_txroom(struct uart_port *port)
328 {
329 if (port->mapbase == 0xffe00000 ||
330 port->mapbase == 0xffe08000)
331 /* SCIF0/1*/
332 return SCIF_TXROOM_MAX - scif_txfill(port);
333 else
334 /* SCIF2 */
335 return SCIF2_TXROOM_MAX - scif_txfill(port);
336 }
337
338 static int scif_rxfill(struct uart_port *port)
339 {
340 if ((port->mapbase == 0xffe00000) ||
341 (port->mapbase == 0xffe08000)) {
342 /* SCIF0/1*/
343 return sci_in(port, SCRFDR) & 0xff;
344 } else {
345 /* SCIF2 */
346 return sci_in(port, SCFDR) & SCIF2_RFDC_MASK;
347 }
348 }
349 #else
350 static int scif_txfill(struct uart_port *port)
351 {
352 return sci_in(port, SCFDR) >> 8;
353 }
354
355 static int scif_txroom(struct uart_port *port)
356 {
357 return SCIF_TXROOM_MAX - scif_txfill(port);
358 }
359
360 static int scif_rxfill(struct uart_port *port)
361 {
362 return sci_in(port, SCFDR) & SCIF_RFDC_MASK;
363 }
364 #endif
365
366 static int sci_txfill(struct uart_port *port)
367 {
368 return !(sci_in(port, SCxSR) & SCI_TDRE);
369 }
370
371 static int sci_txroom(struct uart_port *port)
372 {
373 return !sci_txfill(port);
374 }
375
376 static int sci_rxfill(struct uart_port *port)
377 {
378 return (sci_in(port, SCxSR) & SCxSR_RDxF(port)) != 0;
379 }
380
381 /* ********************************************************************** *
382 * the interrupt related routines *
383 * ********************************************************************** */
384
385 static void sci_transmit_chars(struct uart_port *port)
386 {
387 struct circ_buf *xmit = &port->state->xmit;
388 unsigned int stopped = uart_tx_stopped(port);
389 unsigned short status;
390 unsigned short ctrl;
391 int count;
392
393 status = sci_in(port, SCxSR);
394 if (!(status & SCxSR_TDxE(port))) {
395 ctrl = sci_in(port, SCSCR);
396 if (uart_circ_empty(xmit))
397 ctrl &= ~SCI_CTRL_FLAGS_TIE;
398 else
399 ctrl |= SCI_CTRL_FLAGS_TIE;
400 sci_out(port, SCSCR, ctrl);
401 return;
402 }
403
404 if (port->type == PORT_SCI)
405 count = sci_txroom(port);
406 else
407 count = scif_txroom(port);
408
409 do {
410 unsigned char c;
411
412 if (port->x_char) {
413 c = port->x_char;
414 port->x_char = 0;
415 } else if (!uart_circ_empty(xmit) && !stopped) {
416 c = xmit->buf[xmit->tail];
417 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
418 } else {
419 break;
420 }
421
422 sci_out(port, SCxTDR, c);
423
424 port->icount.tx++;
425 } while (--count > 0);
426
427 sci_out(port, SCxSR, SCxSR_TDxE_CLEAR(port));
428
429 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
430 uart_write_wakeup(port);
431 if (uart_circ_empty(xmit)) {
432 sci_stop_tx(port);
433 } else {
434 ctrl = sci_in(port, SCSCR);
435
436 if (port->type != PORT_SCI) {
437 sci_in(port, SCxSR); /* Dummy read */
438 sci_out(port, SCxSR, SCxSR_TDxE_CLEAR(port));
439 }
440
441 ctrl |= SCI_CTRL_FLAGS_TIE;
442 sci_out(port, SCSCR, ctrl);
443 }
444 }
445
446 /* On SH3, SCIF may read end-of-break as a space->mark char */
447 #define STEPFN(c) ({int __c = (c); (((__c-1)|(__c)) == -1); })
448
449 static inline void sci_receive_chars(struct uart_port *port)
450 {
451 struct sci_port *sci_port = to_sci_port(port);
452 struct tty_struct *tty = port->state->port.tty;
453 int i, count, copied = 0;
454 unsigned short status;
455 unsigned char flag;
456
457 status = sci_in(port, SCxSR);
458 if (!(status & SCxSR_RDxF(port)))
459 return;
460
461 while (1) {
462 if (port->type == PORT_SCI)
463 count = sci_rxfill(port);
464 else
465 count = scif_rxfill(port);
466
467 /* Don't copy more bytes than there is room for in the buffer */
468 count = tty_buffer_request_room(tty, count);
469
470 /* If for any reason we can't copy more data, we're done! */
471 if (count == 0)
472 break;
473
474 if (port->type == PORT_SCI) {
475 char c = sci_in(port, SCxRDR);
476 if (uart_handle_sysrq_char(port, c) ||
477 sci_port->break_flag)
478 count = 0;
479 else
480 tty_insert_flip_char(tty, c, TTY_NORMAL);
481 } else {
482 for (i = 0; i < count; i++) {
483 char c = sci_in(port, SCxRDR);
484 status = sci_in(port, SCxSR);
485 #if defined(CONFIG_CPU_SH3)
486 /* Skip "chars" during break */
487 if (sci_port->break_flag) {
488 if ((c == 0) &&
489 (status & SCxSR_FER(port))) {
490 count--; i--;
491 continue;
492 }
493
494 /* Nonzero => end-of-break */
495 dev_dbg(port->dev, "debounce<%02x>\n", c);
496 sci_port->break_flag = 0;
497
498 if (STEPFN(c)) {
499 count--; i--;
500 continue;
501 }
502 }
503 #endif /* CONFIG_CPU_SH3 */
504 if (uart_handle_sysrq_char(port, c)) {
505 count--; i--;
506 continue;
507 }
508
509 /* Store data and status */
510 if (status & SCxSR_FER(port)) {
511 flag = TTY_FRAME;
512 dev_notice(port->dev, "frame error\n");
513 } else if (status & SCxSR_PER(port)) {
514 flag = TTY_PARITY;
515 dev_notice(port->dev, "parity error\n");
516 } else
517 flag = TTY_NORMAL;
518
519 tty_insert_flip_char(tty, c, flag);
520 }
521 }
522
523 sci_in(port, SCxSR); /* dummy read */
524 sci_out(port, SCxSR, SCxSR_RDxF_CLEAR(port));
525
526 copied += count;
527 port->icount.rx += count;
528 }
529
530 if (copied) {
531 /* Tell the rest of the system the news. New characters! */
532 tty_flip_buffer_push(tty);
533 } else {
534 sci_in(port, SCxSR); /* dummy read */
535 sci_out(port, SCxSR, SCxSR_RDxF_CLEAR(port));
536 }
537 }
538
539 #define SCI_BREAK_JIFFIES (HZ/20)
540 /* The sci generates interrupts during the break,
541 * 1 per millisecond or so during the break period, for 9600 baud.
542 * So dont bother disabling interrupts.
543 * But dont want more than 1 break event.
544 * Use a kernel timer to periodically poll the rx line until
545 * the break is finished.
546 */
547 static void sci_schedule_break_timer(struct sci_port *port)
548 {
549 port->break_timer.expires = jiffies + SCI_BREAK_JIFFIES;
550 add_timer(&port->break_timer);
551 }
552 /* Ensure that two consecutive samples find the break over. */
553 static void sci_break_timer(unsigned long data)
554 {
555 struct sci_port *port = (struct sci_port *)data;
556
557 if (sci_rxd_in(&port->port) == 0) {
558 port->break_flag = 1;
559 sci_schedule_break_timer(port);
560 } else if (port->break_flag == 1) {
561 /* break is over. */
562 port->break_flag = 2;
563 sci_schedule_break_timer(port);
564 } else
565 port->break_flag = 0;
566 }
567
568 static inline int sci_handle_errors(struct uart_port *port)
569 {
570 int copied = 0;
571 unsigned short status = sci_in(port, SCxSR);
572 struct tty_struct *tty = port->state->port.tty;
573
574 if (status & SCxSR_ORER(port)) {
575 /* overrun error */
576 if (tty_insert_flip_char(tty, 0, TTY_OVERRUN))
577 copied++;
578
579 dev_notice(port->dev, "overrun error");
580 }
581
582 if (status & SCxSR_FER(port)) {
583 if (sci_rxd_in(port) == 0) {
584 /* Notify of BREAK */
585 struct sci_port *sci_port = to_sci_port(port);
586
587 if (!sci_port->break_flag) {
588 sci_port->break_flag = 1;
589 sci_schedule_break_timer(sci_port);
590
591 /* Do sysrq handling. */
592 if (uart_handle_break(port))
593 return 0;
594
595 dev_dbg(port->dev, "BREAK detected\n");
596
597 if (tty_insert_flip_char(tty, 0, TTY_BREAK))
598 copied++;
599 }
600
601 } else {
602 /* frame error */
603 if (tty_insert_flip_char(tty, 0, TTY_FRAME))
604 copied++;
605
606 dev_notice(port->dev, "frame error\n");
607 }
608 }
609
610 if (status & SCxSR_PER(port)) {
611 /* parity error */
612 if (tty_insert_flip_char(tty, 0, TTY_PARITY))
613 copied++;
614
615 dev_notice(port->dev, "parity error");
616 }
617
618 if (copied)
619 tty_flip_buffer_push(tty);
620
621 return copied;
622 }
623
624 static inline int sci_handle_fifo_overrun(struct uart_port *port)
625 {
626 struct tty_struct *tty = port->state->port.tty;
627 int copied = 0;
628
629 if (port->type != PORT_SCIF)
630 return 0;
631
632 if ((sci_in(port, SCLSR) & SCIF_ORER) != 0) {
633 sci_out(port, SCLSR, 0);
634
635 tty_insert_flip_char(tty, 0, TTY_OVERRUN);
636 tty_flip_buffer_push(tty);
637
638 dev_notice(port->dev, "overrun error\n");
639 copied++;
640 }
641
642 return copied;
643 }
644
645 static inline int sci_handle_breaks(struct uart_port *port)
646 {
647 int copied = 0;
648 unsigned short status = sci_in(port, SCxSR);
649 struct tty_struct *tty = port->state->port.tty;
650 struct sci_port *s = to_sci_port(port);
651
652 if (uart_handle_break(port))
653 return 0;
654
655 if (!s->break_flag && status & SCxSR_BRK(port)) {
656 #if defined(CONFIG_CPU_SH3)
657 /* Debounce break */
658 s->break_flag = 1;
659 #endif
660 /* Notify of BREAK */
661 if (tty_insert_flip_char(tty, 0, TTY_BREAK))
662 copied++;
663
664 dev_dbg(port->dev, "BREAK detected\n");
665 }
666
667 if (copied)
668 tty_flip_buffer_push(tty);
669
670 copied += sci_handle_fifo_overrun(port);
671
672 return copied;
673 }
674
675 static irqreturn_t sci_rx_interrupt(int irq, void *ptr)
676 {
677 #ifdef CONFIG_SERIAL_SH_SCI_DMA
678 struct uart_port *port = ptr;
679 struct sci_port *s = to_sci_port(port);
680
681 if (s->chan_rx) {
682 u16 scr = sci_in(port, SCSCR);
683 u16 ssr = sci_in(port, SCxSR);
684
685 /* Disable future Rx interrupts */
686 if (port->type == PORT_SCIFA) {
687 disable_irq_nosync(irq);
688 scr |= 0x4000;
689 } else {
690 scr &= ~SCI_CTRL_FLAGS_RIE;
691 }
692 sci_out(port, SCSCR, scr);
693 /* Clear current interrupt */
694 sci_out(port, SCxSR, ssr & ~(1 | SCxSR_RDxF(port)));
695 dev_dbg(port->dev, "Rx IRQ %lu: setup t-out in %u jiffies\n",
696 jiffies, s->rx_timeout);
697 mod_timer(&s->rx_timer, jiffies + s->rx_timeout);
698
699 return IRQ_HANDLED;
700 }
701 #endif
702
703 /* I think sci_receive_chars has to be called irrespective
704 * of whether the I_IXOFF is set, otherwise, how is the interrupt
705 * to be disabled?
706 */
707 sci_receive_chars(ptr);
708
709 return IRQ_HANDLED;
710 }
711
712 static irqreturn_t sci_tx_interrupt(int irq, void *ptr)
713 {
714 struct uart_port *port = ptr;
715 unsigned long flags;
716
717 spin_lock_irqsave(&port->lock, flags);
718 sci_transmit_chars(port);
719 spin_unlock_irqrestore(&port->lock, flags);
720
721 return IRQ_HANDLED;
722 }
723
724 static irqreturn_t sci_er_interrupt(int irq, void *ptr)
725 {
726 struct uart_port *port = ptr;
727
728 /* Handle errors */
729 if (port->type == PORT_SCI) {
730 if (sci_handle_errors(port)) {
731 /* discard character in rx buffer */
732 sci_in(port, SCxSR);
733 sci_out(port, SCxSR, SCxSR_RDxF_CLEAR(port));
734 }
735 } else {
736 sci_handle_fifo_overrun(port);
737 sci_rx_interrupt(irq, ptr);
738 }
739
740 sci_out(port, SCxSR, SCxSR_ERROR_CLEAR(port));
741
742 /* Kick the transmission */
743 sci_tx_interrupt(irq, ptr);
744
745 return IRQ_HANDLED;
746 }
747
748 static irqreturn_t sci_br_interrupt(int irq, void *ptr)
749 {
750 struct uart_port *port = ptr;
751
752 /* Handle BREAKs */
753 sci_handle_breaks(port);
754 sci_out(port, SCxSR, SCxSR_BREAK_CLEAR(port));
755
756 return IRQ_HANDLED;
757 }
758
759 static irqreturn_t sci_mpxed_interrupt(int irq, void *ptr)
760 {
761 unsigned short ssr_status, scr_status, err_enabled;
762 struct uart_port *port = ptr;
763 struct sci_port *s = to_sci_port(port);
764 irqreturn_t ret = IRQ_NONE;
765
766 ssr_status = sci_in(port, SCxSR);
767 scr_status = sci_in(port, SCSCR);
768 err_enabled = scr_status & (SCI_CTRL_FLAGS_REIE | SCI_CTRL_FLAGS_RIE);
769
770 /* Tx Interrupt */
771 if ((ssr_status & SCxSR_TDxE(port)) && (scr_status & SCI_CTRL_FLAGS_TIE) &&
772 !s->chan_tx)
773 ret = sci_tx_interrupt(irq, ptr);
774 /*
775 * Rx Interrupt: if we're using DMA, the DMA controller clears RDF /
776 * DR flags
777 */
778 if (((ssr_status & SCxSR_RDxF(port)) || s->chan_rx) &&
779 (scr_status & SCI_CTRL_FLAGS_RIE))
780 ret = sci_rx_interrupt(irq, ptr);
781 /* Error Interrupt */
782 if ((ssr_status & SCxSR_ERRORS(port)) && err_enabled)
783 ret = sci_er_interrupt(irq, ptr);
784 /* Break Interrupt */
785 if ((ssr_status & SCxSR_BRK(port)) && err_enabled)
786 ret = sci_br_interrupt(irq, ptr);
787
788 return ret;
789 }
790
791 /*
792 * Here we define a transistion notifier so that we can update all of our
793 * ports' baud rate when the peripheral clock changes.
794 */
795 static int sci_notifier(struct notifier_block *self,
796 unsigned long phase, void *p)
797 {
798 struct sh_sci_priv *priv = container_of(self,
799 struct sh_sci_priv, clk_nb);
800 struct sci_port *sci_port;
801 unsigned long flags;
802
803 if ((phase == CPUFREQ_POSTCHANGE) ||
804 (phase == CPUFREQ_RESUMECHANGE)) {
805 spin_lock_irqsave(&priv->lock, flags);
806 list_for_each_entry(sci_port, &priv->ports, node)
807 sci_port->port.uartclk = clk_get_rate(sci_port->iclk);
808 spin_unlock_irqrestore(&priv->lock, flags);
809 }
810
811 return NOTIFY_OK;
812 }
813
814 static void sci_clk_enable(struct uart_port *port)
815 {
816 struct sci_port *sci_port = to_sci_port(port);
817
818 clk_enable(sci_port->iclk);
819 sci_port->port.uartclk = clk_get_rate(sci_port->iclk);
820 clk_enable(sci_port->fclk);
821 }
822
823 static void sci_clk_disable(struct uart_port *port)
824 {
825 struct sci_port *sci_port = to_sci_port(port);
826
827 clk_disable(sci_port->fclk);
828 clk_disable(sci_port->iclk);
829 }
830
831 static int sci_request_irq(struct sci_port *port)
832 {
833 int i;
834 irqreturn_t (*handlers[4])(int irq, void *ptr) = {
835 sci_er_interrupt, sci_rx_interrupt, sci_tx_interrupt,
836 sci_br_interrupt,
837 };
838 const char *desc[] = { "SCI Receive Error", "SCI Receive Data Full",
839 "SCI Transmit Data Empty", "SCI Break" };
840
841 if (port->irqs[0] == port->irqs[1]) {
842 if (unlikely(!port->irqs[0]))
843 return -ENODEV;
844
845 if (request_irq(port->irqs[0], sci_mpxed_interrupt,
846 IRQF_DISABLED, "sci", port)) {
847 dev_err(port->port.dev, "Can't allocate IRQ\n");
848 return -ENODEV;
849 }
850 } else {
851 for (i = 0; i < ARRAY_SIZE(handlers); i++) {
852 if (unlikely(!port->irqs[i]))
853 continue;
854
855 if (request_irq(port->irqs[i], handlers[i],
856 IRQF_DISABLED, desc[i], port)) {
857 dev_err(port->port.dev, "Can't allocate IRQ\n");
858 return -ENODEV;
859 }
860 }
861 }
862
863 return 0;
864 }
865
866 static void sci_free_irq(struct sci_port *port)
867 {
868 int i;
869
870 if (port->irqs[0] == port->irqs[1])
871 free_irq(port->irqs[0], port);
872 else {
873 for (i = 0; i < ARRAY_SIZE(port->irqs); i++) {
874 if (!port->irqs[i])
875 continue;
876
877 free_irq(port->irqs[i], port);
878 }
879 }
880 }
881
882 static unsigned int sci_tx_empty(struct uart_port *port)
883 {
884 unsigned short status = sci_in(port, SCxSR);
885 unsigned short in_tx_fifo = scif_txfill(port);
886
887 return (status & SCxSR_TEND(port)) && !in_tx_fifo ? TIOCSER_TEMT : 0;
888 }
889
890 static void sci_set_mctrl(struct uart_port *port, unsigned int mctrl)
891 {
892 /* This routine is used for seting signals of: DTR, DCD, CTS/RTS */
893 /* We use SCIF's hardware for CTS/RTS, so don't need any for that. */
894 /* If you have signals for DTR and DCD, please implement here. */
895 }
896
897 static unsigned int sci_get_mctrl(struct uart_port *port)
898 {
899 /* This routine is used for getting signals of: DTR, DCD, DSR, RI,
900 and CTS/RTS */
901
902 return TIOCM_DTR | TIOCM_RTS | TIOCM_DSR;
903 }
904
905 #ifdef CONFIG_SERIAL_SH_SCI_DMA
906 static void sci_dma_tx_complete(void *arg)
907 {
908 struct sci_port *s = arg;
909 struct uart_port *port = &s->port;
910 struct circ_buf *xmit = &port->state->xmit;
911 unsigned long flags;
912
913 dev_dbg(port->dev, "%s(%d)\n", __func__, port->line);
914
915 spin_lock_irqsave(&port->lock, flags);
916
917 xmit->tail += sg_dma_len(&s->sg_tx);
918 xmit->tail &= UART_XMIT_SIZE - 1;
919
920 port->icount.tx += sg_dma_len(&s->sg_tx);
921
922 async_tx_ack(s->desc_tx);
923 s->cookie_tx = -EINVAL;
924 s->desc_tx = NULL;
925
926 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
927 uart_write_wakeup(port);
928
929 if (!uart_circ_empty(xmit)) {
930 schedule_work(&s->work_tx);
931 } else if (port->type == PORT_SCIFA) {
932 u16 ctrl = sci_in(port, SCSCR);
933 sci_out(port, SCSCR, ctrl & ~SCI_CTRL_FLAGS_TIE);
934 }
935
936 spin_unlock_irqrestore(&port->lock, flags);
937 }
938
939 /* Locking: called with port lock held */
940 static int sci_dma_rx_push(struct sci_port *s, struct tty_struct *tty,
941 size_t count)
942 {
943 struct uart_port *port = &s->port;
944 int i, active, room;
945
946 room = tty_buffer_request_room(tty, count);
947
948 if (s->active_rx == s->cookie_rx[0]) {
949 active = 0;
950 } else if (s->active_rx == s->cookie_rx[1]) {
951 active = 1;
952 } else {
953 dev_err(port->dev, "cookie %d not found!\n", s->active_rx);
954 return 0;
955 }
956
957 if (room < count)
958 dev_warn(port->dev, "Rx overrun: dropping %u bytes\n",
959 count - room);
960 if (!room)
961 return room;
962
963 for (i = 0; i < room; i++)
964 tty_insert_flip_char(tty, ((u8 *)sg_virt(&s->sg_rx[active]))[i],
965 TTY_NORMAL);
966
967 port->icount.rx += room;
968
969 return room;
970 }
971
972 static void sci_dma_rx_complete(void *arg)
973 {
974 struct sci_port *s = arg;
975 struct uart_port *port = &s->port;
976 struct tty_struct *tty = port->state->port.tty;
977 unsigned long flags;
978 int count;
979
980 dev_dbg(port->dev, "%s(%d) active #%d\n", __func__, port->line, s->active_rx);
981
982 spin_lock_irqsave(&port->lock, flags);
983
984 count = sci_dma_rx_push(s, tty, s->buf_len_rx);
985
986 mod_timer(&s->rx_timer, jiffies + s->rx_timeout);
987
988 spin_unlock_irqrestore(&port->lock, flags);
989
990 if (count)
991 tty_flip_buffer_push(tty);
992
993 schedule_work(&s->work_rx);
994 }
995
996 static void sci_start_rx(struct uart_port *port);
997 static void sci_start_tx(struct uart_port *port);
998
999 static void sci_rx_dma_release(struct sci_port *s, bool enable_pio)
1000 {
1001 struct dma_chan *chan = s->chan_rx;
1002 struct uart_port *port = &s->port;
1003
1004 s->chan_rx = NULL;
1005 s->cookie_rx[0] = s->cookie_rx[1] = -EINVAL;
1006 dma_release_channel(chan);
1007 if (sg_dma_address(&s->sg_rx[0]))
1008 dma_free_coherent(port->dev, s->buf_len_rx * 2,
1009 sg_virt(&s->sg_rx[0]), sg_dma_address(&s->sg_rx[0]));
1010 if (enable_pio)
1011 sci_start_rx(port);
1012 }
1013
1014 static void sci_tx_dma_release(struct sci_port *s, bool enable_pio)
1015 {
1016 struct dma_chan *chan = s->chan_tx;
1017 struct uart_port *port = &s->port;
1018
1019 s->chan_tx = NULL;
1020 s->cookie_tx = -EINVAL;
1021 dma_release_channel(chan);
1022 if (enable_pio)
1023 sci_start_tx(port);
1024 }
1025
1026 static void sci_submit_rx(struct sci_port *s)
1027 {
1028 struct dma_chan *chan = s->chan_rx;
1029 int i;
1030
1031 for (i = 0; i < 2; i++) {
1032 struct scatterlist *sg = &s->sg_rx[i];
1033 struct dma_async_tx_descriptor *desc;
1034
1035 desc = chan->device->device_prep_slave_sg(chan,
1036 sg, 1, DMA_FROM_DEVICE, DMA_PREP_INTERRUPT);
1037
1038 if (desc) {
1039 s->desc_rx[i] = desc;
1040 desc->callback = sci_dma_rx_complete;
1041 desc->callback_param = s;
1042 s->cookie_rx[i] = desc->tx_submit(desc);
1043 }
1044
1045 if (!desc || s->cookie_rx[i] < 0) {
1046 if (i) {
1047 async_tx_ack(s->desc_rx[0]);
1048 s->cookie_rx[0] = -EINVAL;
1049 }
1050 if (desc) {
1051 async_tx_ack(desc);
1052 s->cookie_rx[i] = -EINVAL;
1053 }
1054 dev_warn(s->port.dev,
1055 "failed to re-start DMA, using PIO\n");
1056 sci_rx_dma_release(s, true);
1057 return;
1058 }
1059 dev_dbg(s->port.dev, "%s(): cookie %d to #%d\n", __func__,
1060 s->cookie_rx[i], i);
1061 }
1062
1063 s->active_rx = s->cookie_rx[0];
1064
1065 dma_async_issue_pending(chan);
1066 }
1067
1068 static void work_fn_rx(struct work_struct *work)
1069 {
1070 struct sci_port *s = container_of(work, struct sci_port, work_rx);
1071 struct uart_port *port = &s->port;
1072 struct dma_async_tx_descriptor *desc;
1073 int new;
1074
1075 if (s->active_rx == s->cookie_rx[0]) {
1076 new = 0;
1077 } else if (s->active_rx == s->cookie_rx[1]) {
1078 new = 1;
1079 } else {
1080 dev_err(port->dev, "cookie %d not found!\n", s->active_rx);
1081 return;
1082 }
1083 desc = s->desc_rx[new];
1084
1085 if (dma_async_is_tx_complete(s->chan_rx, s->active_rx, NULL, NULL) !=
1086 DMA_SUCCESS) {
1087 /* Handle incomplete DMA receive */
1088 struct tty_struct *tty = port->state->port.tty;
1089 struct dma_chan *chan = s->chan_rx;
1090 struct sh_desc *sh_desc = container_of(desc, struct sh_desc,
1091 async_tx);
1092 unsigned long flags;
1093 int count;
1094
1095 chan->device->device_control(chan, DMA_TERMINATE_ALL, 0);
1096 dev_dbg(port->dev, "Read %u bytes with cookie %d\n",
1097 sh_desc->partial, sh_desc->cookie);
1098
1099 spin_lock_irqsave(&port->lock, flags);
1100 count = sci_dma_rx_push(s, tty, sh_desc->partial);
1101 spin_unlock_irqrestore(&port->lock, flags);
1102
1103 if (count)
1104 tty_flip_buffer_push(tty);
1105
1106 sci_submit_rx(s);
1107
1108 return;
1109 }
1110
1111 s->cookie_rx[new] = desc->tx_submit(desc);
1112 if (s->cookie_rx[new] < 0) {
1113 dev_warn(port->dev, "Failed submitting Rx DMA descriptor\n");
1114 sci_rx_dma_release(s, true);
1115 return;
1116 }
1117
1118 s->active_rx = s->cookie_rx[!new];
1119
1120 dev_dbg(port->dev, "%s: cookie %d #%d, new active #%d\n", __func__,
1121 s->cookie_rx[new], new, s->active_rx);
1122 }
1123
1124 static void work_fn_tx(struct work_struct *work)
1125 {
1126 struct sci_port *s = container_of(work, struct sci_port, work_tx);
1127 struct dma_async_tx_descriptor *desc;
1128 struct dma_chan *chan = s->chan_tx;
1129 struct uart_port *port = &s->port;
1130 struct circ_buf *xmit = &port->state->xmit;
1131 struct scatterlist *sg = &s->sg_tx;
1132
1133 /*
1134 * DMA is idle now.
1135 * Port xmit buffer is already mapped, and it is one page... Just adjust
1136 * offsets and lengths. Since it is a circular buffer, we have to
1137 * transmit till the end, and then the rest. Take the port lock to get a
1138 * consistent xmit buffer state.
1139 */
1140 spin_lock_irq(&port->lock);
1141 sg->offset = xmit->tail & (UART_XMIT_SIZE - 1);
1142 sg_dma_address(sg) = (sg_dma_address(sg) & ~(UART_XMIT_SIZE - 1)) +
1143 sg->offset;
1144 sg_dma_len(sg) = min((int)CIRC_CNT(xmit->head, xmit->tail, UART_XMIT_SIZE),
1145 CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE));
1146 spin_unlock_irq(&port->lock);
1147
1148 BUG_ON(!sg_dma_len(sg));
1149
1150 desc = chan->device->device_prep_slave_sg(chan,
1151 sg, s->sg_len_tx, DMA_TO_DEVICE,
1152 DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1153 if (!desc) {
1154 /* switch to PIO */
1155 sci_tx_dma_release(s, true);
1156 return;
1157 }
1158
1159 dma_sync_sg_for_device(port->dev, sg, 1, DMA_TO_DEVICE);
1160
1161 spin_lock_irq(&port->lock);
1162 s->desc_tx = desc;
1163 desc->callback = sci_dma_tx_complete;
1164 desc->callback_param = s;
1165 spin_unlock_irq(&port->lock);
1166 s->cookie_tx = desc->tx_submit(desc);
1167 if (s->cookie_tx < 0) {
1168 dev_warn(port->dev, "Failed submitting Tx DMA descriptor\n");
1169 /* switch to PIO */
1170 sci_tx_dma_release(s, true);
1171 return;
1172 }
1173
1174 dev_dbg(port->dev, "%s: %p: %d...%d, cookie %d\n", __func__,
1175 xmit->buf, xmit->tail, xmit->head, s->cookie_tx);
1176
1177 dma_async_issue_pending(chan);
1178 }
1179 #endif
1180
1181 static void sci_start_tx(struct uart_port *port)
1182 {
1183 struct sci_port *s = to_sci_port(port);
1184 unsigned short ctrl;
1185
1186 #ifdef CONFIG_SERIAL_SH_SCI_DMA
1187 if (port->type == PORT_SCIFA) {
1188 u16 new, scr = sci_in(port, SCSCR);
1189 if (s->chan_tx)
1190 new = scr | 0x8000;
1191 else
1192 new = scr & ~0x8000;
1193 if (new != scr)
1194 sci_out(port, SCSCR, new);
1195 }
1196 if (s->chan_tx && !uart_circ_empty(&s->port.state->xmit) &&
1197 s->cookie_tx < 0)
1198 schedule_work(&s->work_tx);
1199 #endif
1200 if (!s->chan_tx || port->type == PORT_SCIFA) {
1201 /* Set TIE (Transmit Interrupt Enable) bit in SCSCR */
1202 ctrl = sci_in(port, SCSCR);
1203 sci_out(port, SCSCR, ctrl | SCI_CTRL_FLAGS_TIE);
1204 }
1205 }
1206
1207 static void sci_stop_tx(struct uart_port *port)
1208 {
1209 unsigned short ctrl;
1210
1211 /* Clear TIE (Transmit Interrupt Enable) bit in SCSCR */
1212 ctrl = sci_in(port, SCSCR);
1213 if (port->type == PORT_SCIFA)
1214 ctrl &= ~0x8000;
1215 ctrl &= ~SCI_CTRL_FLAGS_TIE;
1216 sci_out(port, SCSCR, ctrl);
1217 }
1218
1219 static void sci_start_rx(struct uart_port *port)
1220 {
1221 unsigned short ctrl = SCI_CTRL_FLAGS_RIE | SCI_CTRL_FLAGS_REIE;
1222
1223 /* Set RIE (Receive Interrupt Enable) bit in SCSCR */
1224 ctrl |= sci_in(port, SCSCR);
1225 if (port->type == PORT_SCIFA)
1226 ctrl &= ~0x4000;
1227 sci_out(port, SCSCR, ctrl);
1228 }
1229
1230 static void sci_stop_rx(struct uart_port *port)
1231 {
1232 unsigned short ctrl;
1233
1234 /* Clear RIE (Receive Interrupt Enable) bit in SCSCR */
1235 ctrl = sci_in(port, SCSCR);
1236 if (port->type == PORT_SCIFA)
1237 ctrl &= ~0x4000;
1238 ctrl &= ~(SCI_CTRL_FLAGS_RIE | SCI_CTRL_FLAGS_REIE);
1239 sci_out(port, SCSCR, ctrl);
1240 }
1241
1242 static void sci_enable_ms(struct uart_port *port)
1243 {
1244 /* Nothing here yet .. */
1245 }
1246
1247 static void sci_break_ctl(struct uart_port *port, int break_state)
1248 {
1249 /* Nothing here yet .. */
1250 }
1251
1252 #ifdef CONFIG_SERIAL_SH_SCI_DMA
1253 static bool filter(struct dma_chan *chan, void *slave)
1254 {
1255 struct sh_dmae_slave *param = slave;
1256
1257 dev_dbg(chan->device->dev, "%s: slave ID %d\n", __func__,
1258 param->slave_id);
1259
1260 if (param->dma_dev == chan->device->dev) {
1261 chan->private = param;
1262 return true;
1263 } else {
1264 return false;
1265 }
1266 }
1267
1268 static void rx_timer_fn(unsigned long arg)
1269 {
1270 struct sci_port *s = (struct sci_port *)arg;
1271 struct uart_port *port = &s->port;
1272 u16 scr = sci_in(port, SCSCR);
1273
1274 if (port->type == PORT_SCIFA) {
1275 scr &= ~0x4000;
1276 enable_irq(s->irqs[1]);
1277 }
1278 sci_out(port, SCSCR, scr | SCI_CTRL_FLAGS_RIE);
1279 dev_dbg(port->dev, "DMA Rx timed out\n");
1280 schedule_work(&s->work_rx);
1281 }
1282
1283 static void sci_request_dma(struct uart_port *port)
1284 {
1285 struct sci_port *s = to_sci_port(port);
1286 struct sh_dmae_slave *param;
1287 struct dma_chan *chan;
1288 dma_cap_mask_t mask;
1289 int nent;
1290
1291 dev_dbg(port->dev, "%s: port %d DMA %p\n", __func__,
1292 port->line, s->dma_dev);
1293
1294 if (!s->dma_dev)
1295 return;
1296
1297 dma_cap_zero(mask);
1298 dma_cap_set(DMA_SLAVE, mask);
1299
1300 param = &s->param_tx;
1301
1302 /* Slave ID, e.g., SHDMA_SLAVE_SCIF0_TX */
1303 param->slave_id = s->slave_tx;
1304 param->dma_dev = s->dma_dev;
1305
1306 s->cookie_tx = -EINVAL;
1307 chan = dma_request_channel(mask, filter, param);
1308 dev_dbg(port->dev, "%s: TX: got channel %p\n", __func__, chan);
1309 if (chan) {
1310 s->chan_tx = chan;
1311 sg_init_table(&s->sg_tx, 1);
1312 /* UART circular tx buffer is an aligned page. */
1313 BUG_ON((int)port->state->xmit.buf & ~PAGE_MASK);
1314 sg_set_page(&s->sg_tx, virt_to_page(port->state->xmit.buf),
1315 UART_XMIT_SIZE, (int)port->state->xmit.buf & ~PAGE_MASK);
1316 nent = dma_map_sg(port->dev, &s->sg_tx, 1, DMA_TO_DEVICE);
1317 if (!nent)
1318 sci_tx_dma_release(s, false);
1319 else
1320 dev_dbg(port->dev, "%s: mapped %d@%p to %x\n", __func__,
1321 sg_dma_len(&s->sg_tx),
1322 port->state->xmit.buf, sg_dma_address(&s->sg_tx));
1323
1324 s->sg_len_tx = nent;
1325
1326 INIT_WORK(&s->work_tx, work_fn_tx);
1327 }
1328
1329 param = &s->param_rx;
1330
1331 /* Slave ID, e.g., SHDMA_SLAVE_SCIF0_RX */
1332 param->slave_id = s->slave_rx;
1333 param->dma_dev = s->dma_dev;
1334
1335 chan = dma_request_channel(mask, filter, param);
1336 dev_dbg(port->dev, "%s: RX: got channel %p\n", __func__, chan);
1337 if (chan) {
1338 dma_addr_t dma[2];
1339 void *buf[2];
1340 int i;
1341
1342 s->chan_rx = chan;
1343
1344 s->buf_len_rx = 2 * max(16, (int)port->fifosize);
1345 buf[0] = dma_alloc_coherent(port->dev, s->buf_len_rx * 2,
1346 &dma[0], GFP_KERNEL);
1347
1348 if (!buf[0]) {
1349 dev_warn(port->dev,
1350 "failed to allocate dma buffer, using PIO\n");
1351 sci_rx_dma_release(s, true);
1352 return;
1353 }
1354
1355 buf[1] = buf[0] + s->buf_len_rx;
1356 dma[1] = dma[0] + s->buf_len_rx;
1357
1358 for (i = 0; i < 2; i++) {
1359 struct scatterlist *sg = &s->sg_rx[i];
1360
1361 sg_init_table(sg, 1);
1362 sg_set_page(sg, virt_to_page(buf[i]), s->buf_len_rx,
1363 (int)buf[i] & ~PAGE_MASK);
1364 sg_dma_address(sg) = dma[i];
1365 }
1366
1367 INIT_WORK(&s->work_rx, work_fn_rx);
1368 setup_timer(&s->rx_timer, rx_timer_fn, (unsigned long)s);
1369
1370 sci_submit_rx(s);
1371 }
1372 }
1373
1374 static void sci_free_dma(struct uart_port *port)
1375 {
1376 struct sci_port *s = to_sci_port(port);
1377
1378 if (!s->dma_dev)
1379 return;
1380
1381 if (s->chan_tx)
1382 sci_tx_dma_release(s, false);
1383 if (s->chan_rx)
1384 sci_rx_dma_release(s, false);
1385 }
1386 #endif
1387
1388 static int sci_startup(struct uart_port *port)
1389 {
1390 struct sci_port *s = to_sci_port(port);
1391
1392 dev_dbg(port->dev, "%s(%d)\n", __func__, port->line);
1393
1394 if (s->enable)
1395 s->enable(port);
1396
1397 sci_request_irq(s);
1398 #ifdef CONFIG_SERIAL_SH_SCI_DMA
1399 sci_request_dma(port);
1400 #endif
1401 sci_start_tx(port);
1402 sci_start_rx(port);
1403
1404 return 0;
1405 }
1406
1407 static void sci_shutdown(struct uart_port *port)
1408 {
1409 struct sci_port *s = to_sci_port(port);
1410
1411 dev_dbg(port->dev, "%s(%d)\n", __func__, port->line);
1412
1413 sci_stop_rx(port);
1414 sci_stop_tx(port);
1415 #ifdef CONFIG_SERIAL_SH_SCI_DMA
1416 sci_free_dma(port);
1417 #endif
1418 sci_free_irq(s);
1419
1420 if (s->disable)
1421 s->disable(port);
1422 }
1423
1424 static void sci_set_termios(struct uart_port *port, struct ktermios *termios,
1425 struct ktermios *old)
1426 {
1427 #ifdef CONFIG_SERIAL_SH_SCI_DMA
1428 struct sci_port *s = to_sci_port(port);
1429 #endif
1430 unsigned int status, baud, smr_val, max_baud;
1431 int t = -1;
1432 u16 scfcr = 0;
1433
1434 /*
1435 * earlyprintk comes here early on with port->uartclk set to zero.
1436 * the clock framework is not up and running at this point so here
1437 * we assume that 115200 is the maximum baud rate. please note that
1438 * the baud rate is not programmed during earlyprintk - it is assumed
1439 * that the previous boot loader has enabled required clocks and
1440 * setup the baud rate generator hardware for us already.
1441 */
1442 max_baud = port->uartclk ? port->uartclk / 16 : 115200;
1443
1444 baud = uart_get_baud_rate(port, termios, old, 0, max_baud);
1445 if (likely(baud && port->uartclk))
1446 t = SCBRR_VALUE(baud, port->uartclk);
1447
1448 do {
1449 status = sci_in(port, SCxSR);
1450 } while (!(status & SCxSR_TEND(port)));
1451
1452 sci_out(port, SCSCR, 0x00); /* TE=0, RE=0, CKE1=0 */
1453
1454 if (port->type != PORT_SCI)
1455 sci_out(port, SCFCR, scfcr | SCFCR_RFRST | SCFCR_TFRST);
1456
1457 smr_val = sci_in(port, SCSMR) & 3;
1458 if ((termios->c_cflag & CSIZE) == CS7)
1459 smr_val |= 0x40;
1460 if (termios->c_cflag & PARENB)
1461 smr_val |= 0x20;
1462 if (termios->c_cflag & PARODD)
1463 smr_val |= 0x30;
1464 if (termios->c_cflag & CSTOPB)
1465 smr_val |= 0x08;
1466
1467 uart_update_timeout(port, termios->c_cflag, baud);
1468
1469 sci_out(port, SCSMR, smr_val);
1470
1471 dev_dbg(port->dev, "%s: SMR %x, t %x, SCSCR %x\n", __func__, smr_val, t,
1472 SCSCR_INIT(port));
1473
1474 if (t > 0) {
1475 if (t >= 256) {
1476 sci_out(port, SCSMR, (sci_in(port, SCSMR) & ~3) | 1);
1477 t >>= 2;
1478 } else
1479 sci_out(port, SCSMR, sci_in(port, SCSMR) & ~3);
1480
1481 sci_out(port, SCBRR, t);
1482 udelay((1000000+(baud-1)) / baud); /* Wait one bit interval */
1483 }
1484
1485 sci_init_pins(port, termios->c_cflag);
1486 sci_out(port, SCFCR, scfcr | ((termios->c_cflag & CRTSCTS) ? SCFCR_MCE : 0));
1487
1488 sci_out(port, SCSCR, SCSCR_INIT(port));
1489
1490 #ifdef CONFIG_SERIAL_SH_SCI_DMA
1491 /*
1492 * Calculate delay for 1.5 DMA buffers: see
1493 * drivers/serial/serial_core.c::uart_update_timeout(). With 10 bits
1494 * (CS8), 250Hz, 115200 baud and 64 bytes FIFO, the above function
1495 * calculates 1 jiffie for the data plus 5 jiffies for the "slop(e)."
1496 * Then below we calculate 3 jiffies (12ms) for 1.5 DMA buffers (3 FIFO
1497 * sizes), but it has been found out experimentally, that this is not
1498 * enough: the driver too often needlessly runs on a DMA timeout. 20ms
1499 * as a minimum seem to work perfectly.
1500 */
1501 if (s->chan_rx) {
1502 s->rx_timeout = (port->timeout - HZ / 50) * s->buf_len_rx * 3 /
1503 port->fifosize / 2;
1504 dev_dbg(port->dev,
1505 "DMA Rx t-out %ums, tty t-out %u jiffies\n",
1506 s->rx_timeout * 1000 / HZ, port->timeout);
1507 if (s->rx_timeout < msecs_to_jiffies(20))
1508 s->rx_timeout = msecs_to_jiffies(20);
1509 }
1510 #endif
1511
1512 if ((termios->c_cflag & CREAD) != 0)
1513 sci_start_rx(port);
1514 }
1515
1516 static const char *sci_type(struct uart_port *port)
1517 {
1518 switch (port->type) {
1519 case PORT_IRDA:
1520 return "irda";
1521 case PORT_SCI:
1522 return "sci";
1523 case PORT_SCIF:
1524 return "scif";
1525 case PORT_SCIFA:
1526 return "scifa";
1527 }
1528
1529 return NULL;
1530 }
1531
1532 static void sci_release_port(struct uart_port *port)
1533 {
1534 /* Nothing here yet .. */
1535 }
1536
1537 static int sci_request_port(struct uart_port *port)
1538 {
1539 /* Nothing here yet .. */
1540 return 0;
1541 }
1542
1543 static void sci_config_port(struct uart_port *port, int flags)
1544 {
1545 struct sci_port *s = to_sci_port(port);
1546
1547 port->type = s->type;
1548
1549 if (port->membase)
1550 return;
1551
1552 if (port->flags & UPF_IOREMAP) {
1553 port->membase = ioremap_nocache(port->mapbase, 0x40);
1554
1555 if (IS_ERR(port->membase))
1556 dev_err(port->dev, "can't remap port#%d\n", port->line);
1557 } else {
1558 /*
1559 * For the simple (and majority of) cases where we don't
1560 * need to do any remapping, just cast the cookie
1561 * directly.
1562 */
1563 port->membase = (void __iomem *)port->mapbase;
1564 }
1565 }
1566
1567 static int sci_verify_port(struct uart_port *port, struct serial_struct *ser)
1568 {
1569 struct sci_port *s = to_sci_port(port);
1570
1571 if (ser->irq != s->irqs[SCIx_TXI_IRQ] || ser->irq > nr_irqs)
1572 return -EINVAL;
1573 if (ser->baud_base < 2400)
1574 /* No paper tape reader for Mitch.. */
1575 return -EINVAL;
1576
1577 return 0;
1578 }
1579
1580 static struct uart_ops sci_uart_ops = {
1581 .tx_empty = sci_tx_empty,
1582 .set_mctrl = sci_set_mctrl,
1583 .get_mctrl = sci_get_mctrl,
1584 .start_tx = sci_start_tx,
1585 .stop_tx = sci_stop_tx,
1586 .stop_rx = sci_stop_rx,
1587 .enable_ms = sci_enable_ms,
1588 .break_ctl = sci_break_ctl,
1589 .startup = sci_startup,
1590 .shutdown = sci_shutdown,
1591 .set_termios = sci_set_termios,
1592 .type = sci_type,
1593 .release_port = sci_release_port,
1594 .request_port = sci_request_port,
1595 .config_port = sci_config_port,
1596 .verify_port = sci_verify_port,
1597 #ifdef CONFIG_CONSOLE_POLL
1598 .poll_get_char = sci_poll_get_char,
1599 .poll_put_char = sci_poll_put_char,
1600 #endif
1601 };
1602
1603 static int __devinit sci_init_single(struct platform_device *dev,
1604 struct sci_port *sci_port,
1605 unsigned int index,
1606 struct plat_sci_port *p)
1607 {
1608 struct uart_port *port = &sci_port->port;
1609
1610 port->ops = &sci_uart_ops;
1611 port->iotype = UPIO_MEM;
1612 port->line = index;
1613
1614 switch (p->type) {
1615 case PORT_SCIFA:
1616 port->fifosize = 64;
1617 break;
1618 case PORT_SCIF:
1619 port->fifosize = 16;
1620 break;
1621 default:
1622 port->fifosize = 1;
1623 break;
1624 }
1625
1626 if (dev) {
1627 sci_port->iclk = clk_get(&dev->dev, "sci_ick");
1628 if (IS_ERR(sci_port->iclk)) {
1629 sci_port->iclk = clk_get(&dev->dev, "peripheral_clk");
1630 if (IS_ERR(sci_port->iclk)) {
1631 dev_err(&dev->dev, "can't get iclk\n");
1632 return PTR_ERR(sci_port->iclk);
1633 }
1634 }
1635
1636 /*
1637 * The function clock is optional, ignore it if we can't
1638 * find it.
1639 */
1640 sci_port->fclk = clk_get(&dev->dev, "sci_fck");
1641 if (IS_ERR(sci_port->fclk))
1642 sci_port->fclk = NULL;
1643
1644 sci_port->enable = sci_clk_enable;
1645 sci_port->disable = sci_clk_disable;
1646 port->dev = &dev->dev;
1647 }
1648
1649 sci_port->break_timer.data = (unsigned long)sci_port;
1650 sci_port->break_timer.function = sci_break_timer;
1651 init_timer(&sci_port->break_timer);
1652
1653 port->mapbase = p->mapbase;
1654 port->membase = p->membase;
1655
1656 port->irq = p->irqs[SCIx_TXI_IRQ];
1657 port->flags = p->flags;
1658 sci_port->type = port->type = p->type;
1659
1660 #ifdef CONFIG_SERIAL_SH_SCI_DMA
1661 sci_port->dma_dev = p->dma_dev;
1662 sci_port->slave_tx = p->dma_slave_tx;
1663 sci_port->slave_rx = p->dma_slave_rx;
1664
1665 dev_dbg(port->dev, "%s: DMA device %p, tx %d, rx %d\n", __func__,
1666 p->dma_dev, p->dma_slave_tx, p->dma_slave_rx);
1667 #endif
1668
1669 memcpy(&sci_port->irqs, &p->irqs, sizeof(p->irqs));
1670 return 0;
1671 }
1672
1673 #ifdef CONFIG_SERIAL_SH_SCI_CONSOLE
1674 static struct tty_driver *serial_console_device(struct console *co, int *index)
1675 {
1676 struct uart_driver *p = &sci_uart_driver;
1677 *index = co->index;
1678 return p->tty_driver;
1679 }
1680
1681 static void serial_console_putchar(struct uart_port *port, int ch)
1682 {
1683 sci_poll_put_char(port, ch);
1684 }
1685
1686 /*
1687 * Print a string to the serial port trying not to disturb
1688 * any possible real use of the port...
1689 */
1690 static void serial_console_write(struct console *co, const char *s,
1691 unsigned count)
1692 {
1693 struct uart_port *port = co->data;
1694 struct sci_port *sci_port = to_sci_port(port);
1695 unsigned short bits;
1696
1697 if (sci_port->enable)
1698 sci_port->enable(port);
1699
1700 uart_console_write(port, s, count, serial_console_putchar);
1701
1702 /* wait until fifo is empty and last bit has been transmitted */
1703 bits = SCxSR_TDxE(port) | SCxSR_TEND(port);
1704 while ((sci_in(port, SCxSR) & bits) != bits)
1705 cpu_relax();
1706
1707 if (sci_port->disable)
1708 sci_port->disable(port);
1709 }
1710
1711 static int __devinit serial_console_setup(struct console *co, char *options)
1712 {
1713 struct sci_port *sci_port;
1714 struct uart_port *port;
1715 int baud = 115200;
1716 int bits = 8;
1717 int parity = 'n';
1718 int flow = 'n';
1719 int ret;
1720
1721 /*
1722 * Check whether an invalid uart number has been specified, and
1723 * if so, search for the first available port that does have
1724 * console support.
1725 */
1726 if (co->index >= SCI_NPORTS)
1727 co->index = 0;
1728
1729 if (co->data) {
1730 port = co->data;
1731 sci_port = to_sci_port(port);
1732 } else {
1733 sci_port = &sci_ports[co->index];
1734 port = &sci_port->port;
1735 co->data = port;
1736 }
1737
1738 /*
1739 * Also need to check port->type, we don't actually have any
1740 * UPIO_PORT ports, but uart_report_port() handily misreports
1741 * it anyways if we don't have a port available by the time this is
1742 * called.
1743 */
1744 if (!port->type)
1745 return -ENODEV;
1746
1747 sci_config_port(port, 0);
1748
1749 if (sci_port->enable)
1750 sci_port->enable(port);
1751
1752 if (options)
1753 uart_parse_options(options, &baud, &parity, &bits, &flow);
1754
1755 ret = uart_set_options(port, co, baud, parity, bits, flow);
1756 #if defined(__H8300H__) || defined(__H8300S__)
1757 /* disable rx interrupt */
1758 if (ret == 0)
1759 sci_stop_rx(port);
1760 #endif
1761 /* TODO: disable clock */
1762 return ret;
1763 }
1764
1765 static struct console serial_console = {
1766 .name = "ttySC",
1767 .device = serial_console_device,
1768 .write = serial_console_write,
1769 .setup = serial_console_setup,
1770 .flags = CON_PRINTBUFFER,
1771 .index = -1,
1772 };
1773
1774 static int __init sci_console_init(void)
1775 {
1776 register_console(&serial_console);
1777 return 0;
1778 }
1779 console_initcall(sci_console_init);
1780
1781 static struct sci_port early_serial_port;
1782 static struct console early_serial_console = {
1783 .name = "early_ttySC",
1784 .write = serial_console_write,
1785 .flags = CON_PRINTBUFFER,
1786 };
1787 static char early_serial_buf[32];
1788
1789 #endif /* CONFIG_SERIAL_SH_SCI_CONSOLE */
1790
1791 #if defined(CONFIG_SERIAL_SH_SCI_CONSOLE)
1792 #define SCI_CONSOLE (&serial_console)
1793 #else
1794 #define SCI_CONSOLE 0
1795 #endif
1796
1797 static char banner[] __initdata =
1798 KERN_INFO "SuperH SCI(F) driver initialized\n";
1799
1800 static struct uart_driver sci_uart_driver = {
1801 .owner = THIS_MODULE,
1802 .driver_name = "sci",
1803 .dev_name = "ttySC",
1804 .major = SCI_MAJOR,
1805 .minor = SCI_MINOR_START,
1806 .nr = SCI_NPORTS,
1807 .cons = SCI_CONSOLE,
1808 };
1809
1810
1811 static int sci_remove(struct platform_device *dev)
1812 {
1813 struct sh_sci_priv *priv = platform_get_drvdata(dev);
1814 struct sci_port *p;
1815 unsigned long flags;
1816
1817 cpufreq_unregister_notifier(&priv->clk_nb, CPUFREQ_TRANSITION_NOTIFIER);
1818
1819 spin_lock_irqsave(&priv->lock, flags);
1820 list_for_each_entry(p, &priv->ports, node) {
1821 uart_remove_one_port(&sci_uart_driver, &p->port);
1822 clk_put(p->iclk);
1823 clk_put(p->fclk);
1824 }
1825 spin_unlock_irqrestore(&priv->lock, flags);
1826
1827 kfree(priv);
1828 return 0;
1829 }
1830
1831 static int __devinit sci_probe_single(struct platform_device *dev,
1832 unsigned int index,
1833 struct plat_sci_port *p,
1834 struct sci_port *sciport)
1835 {
1836 struct sh_sci_priv *priv = platform_get_drvdata(dev);
1837 unsigned long flags;
1838 int ret;
1839
1840 /* Sanity check */
1841 if (unlikely(index >= SCI_NPORTS)) {
1842 dev_notice(&dev->dev, "Attempting to register port "
1843 "%d when only %d are available.\n",
1844 index+1, SCI_NPORTS);
1845 dev_notice(&dev->dev, "Consider bumping "
1846 "CONFIG_SERIAL_SH_SCI_NR_UARTS!\n");
1847 return 0;
1848 }
1849
1850 ret = sci_init_single(dev, sciport, index, p);
1851 if (ret)
1852 return ret;
1853
1854 ret = uart_add_one_port(&sci_uart_driver, &sciport->port);
1855 if (ret)
1856 return ret;
1857
1858 INIT_LIST_HEAD(&sciport->node);
1859
1860 spin_lock_irqsave(&priv->lock, flags);
1861 list_add(&sciport->node, &priv->ports);
1862 spin_unlock_irqrestore(&priv->lock, flags);
1863
1864 return 0;
1865 }
1866
1867 /*
1868 * Register a set of serial devices attached to a platform device. The
1869 * list is terminated with a zero flags entry, which means we expect
1870 * all entries to have at least UPF_BOOT_AUTOCONF set. Platforms that need
1871 * remapping (such as sh64) should also set UPF_IOREMAP.
1872 */
1873 static int __devinit sci_probe(struct platform_device *dev)
1874 {
1875 struct plat_sci_port *p = dev->dev.platform_data;
1876 struct sh_sci_priv *priv;
1877 int i, ret = -EINVAL;
1878
1879 #ifdef CONFIG_SERIAL_SH_SCI_CONSOLE
1880 if (is_early_platform_device(dev)) {
1881 if (dev->id == -1)
1882 return -ENOTSUPP;
1883 early_serial_console.index = dev->id;
1884 early_serial_console.data = &early_serial_port.port;
1885 sci_init_single(NULL, &early_serial_port, dev->id, p);
1886 serial_console_setup(&early_serial_console, early_serial_buf);
1887 if (!strstr(early_serial_buf, "keep"))
1888 early_serial_console.flags |= CON_BOOT;
1889 register_console(&early_serial_console);
1890 return 0;
1891 }
1892 #endif
1893
1894 priv = kzalloc(sizeof(*priv), GFP_KERNEL);
1895 if (!priv)
1896 return -ENOMEM;
1897
1898 INIT_LIST_HEAD(&priv->ports);
1899 spin_lock_init(&priv->lock);
1900 platform_set_drvdata(dev, priv);
1901
1902 priv->clk_nb.notifier_call = sci_notifier;
1903 cpufreq_register_notifier(&priv->clk_nb, CPUFREQ_TRANSITION_NOTIFIER);
1904
1905 if (dev->id != -1) {
1906 ret = sci_probe_single(dev, dev->id, p, &sci_ports[dev->id]);
1907 if (ret)
1908 goto err_unreg;
1909 } else {
1910 for (i = 0; p && p->flags != 0; p++, i++) {
1911 ret = sci_probe_single(dev, i, p, &sci_ports[i]);
1912 if (ret)
1913 goto err_unreg;
1914 }
1915 }
1916
1917 #ifdef CONFIG_SH_STANDARD_BIOS
1918 sh_bios_gdb_detach();
1919 #endif
1920
1921 return 0;
1922
1923 err_unreg:
1924 sci_remove(dev);
1925 return ret;
1926 }
1927
1928 static int sci_suspend(struct device *dev)
1929 {
1930 struct sh_sci_priv *priv = dev_get_drvdata(dev);
1931 struct sci_port *p;
1932 unsigned long flags;
1933
1934 spin_lock_irqsave(&priv->lock, flags);
1935 list_for_each_entry(p, &priv->ports, node)
1936 uart_suspend_port(&sci_uart_driver, &p->port);
1937 spin_unlock_irqrestore(&priv->lock, flags);
1938
1939 return 0;
1940 }
1941
1942 static int sci_resume(struct device *dev)
1943 {
1944 struct sh_sci_priv *priv = dev_get_drvdata(dev);
1945 struct sci_port *p;
1946 unsigned long flags;
1947
1948 spin_lock_irqsave(&priv->lock, flags);
1949 list_for_each_entry(p, &priv->ports, node)
1950 uart_resume_port(&sci_uart_driver, &p->port);
1951 spin_unlock_irqrestore(&priv->lock, flags);
1952
1953 return 0;
1954 }
1955
1956 static const struct dev_pm_ops sci_dev_pm_ops = {
1957 .suspend = sci_suspend,
1958 .resume = sci_resume,
1959 };
1960
1961 static struct platform_driver sci_driver = {
1962 .probe = sci_probe,
1963 .remove = sci_remove,
1964 .driver = {
1965 .name = "sh-sci",
1966 .owner = THIS_MODULE,
1967 .pm = &sci_dev_pm_ops,
1968 },
1969 };
1970
1971 static int __init sci_init(void)
1972 {
1973 int ret;
1974
1975 printk(banner);
1976
1977 ret = uart_register_driver(&sci_uart_driver);
1978 if (likely(ret == 0)) {
1979 ret = platform_driver_register(&sci_driver);
1980 if (unlikely(ret))
1981 uart_unregister_driver(&sci_uart_driver);
1982 }
1983
1984 return ret;
1985 }
1986
1987 static void __exit sci_exit(void)
1988 {
1989 platform_driver_unregister(&sci_driver);
1990 uart_unregister_driver(&sci_uart_driver);
1991 }
1992
1993 #ifdef CONFIG_SERIAL_SH_SCI_CONSOLE
1994 early_platform_init_buffer("earlyprintk", &sci_driver,
1995 early_serial_buf, ARRAY_SIZE(early_serial_buf));
1996 #endif
1997 module_init(sci_init);
1998 module_exit(sci_exit);
1999
2000 MODULE_LICENSE("GPL");
2001 MODULE_ALIAS("platform:sh-sci");
Linux 2.6 ibm-acpi/thinkpad-acpi driver git tree