1 /*
2 * SuperH on-chip serial module support. (SCI with no FIFO / with FIFO)
3 *
4 * Copyright (C) 2002 - 2011 Paul Mundt
5 * Modified to support SH7720 SCIF. Markus Brunner, Mark Jonas (Jul 2007).
6 *
7 * based off of the old drivers/char/sh-sci.c by:
8 *
9 * Copyright (C) 1999, 2000 Niibe Yutaka
10 * Copyright (C) 2000 Sugioka Toshinobu
11 * Modified to support multiple serial ports. Stuart Menefy (May 2000).
12 * Modified to support SecureEdge. David McCullough (2002)
13 * Modified to support SH7300 SCIF. Takashi Kusuda (Jun 2003).
14 * Removed SH7300 support (Jul 2007).
15 *
16 * This file is subject to the terms and conditions of the GNU General Public
17 * License. See the file "COPYING" in the main directory of this archive
18 * for more details.
19 */
20 #if defined(CONFIG_SERIAL_SH_SCI_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
21 #define SUPPORT_SYSRQ
22 #endif
23
24 #undef DEBUG
25
26 #include <linux/module.h>
27 #include <linux/errno.h>
28 #include <linux/timer.h>
29 #include <linux/interrupt.h>
30 #include <linux/tty.h>
31 #include <linux/tty_flip.h>
32 #include <linux/serial.h>
33 #include <linux/major.h>
34 #include <linux/string.h>
35 #include <linux/sysrq.h>
36 #include <linux/ioport.h>
37 #include <linux/mm.h>
38 #include <linux/init.h>
39 #include <linux/delay.h>
40 #include <linux/console.h>
41 #include <linux/platform_device.h>
42 #include <linux/serial_sci.h>
43 #include <linux/notifier.h>
44 #include <linux/pm_runtime.h>
45 #include <linux/cpufreq.h>
46 #include <linux/clk.h>
47 #include <linux/ctype.h>
48 #include <linux/err.h>
49 #include <linux/dmaengine.h>
50 #include <linux/dma-mapping.h>
51 #include <linux/scatterlist.h>
52 #include <linux/slab.h>
53 #include <linux/gpio.h>
54
55 #ifdef CONFIG_SUPERH
56 #include <asm/sh_bios.h>
57 #endif
58
59 #include "sh-sci.h"
60
61 struct sci_port {
62 struct uart_port port;
63
64 /* Platform configuration */
65 struct plat_sci_port *cfg;
66
67 /* Break timer */
68 struct timer_list break_timer;
69 int break_flag;
70
71 /* Interface clock */
72 struct clk *iclk;
73 /* Function clock */
74 struct clk *fclk;
75
76 char *irqstr[SCIx_NR_IRQS];
77 char *gpiostr[SCIx_NR_FNS];
78
79 struct dma_chan *chan_tx;
80 struct dma_chan *chan_rx;
81
82 #ifdef CONFIG_SERIAL_SH_SCI_DMA
83 struct dma_async_tx_descriptor *desc_tx;
84 struct dma_async_tx_descriptor *desc_rx[2];
85 dma_cookie_t cookie_tx;
86 dma_cookie_t cookie_rx[2];
87 dma_cookie_t active_rx;
88 struct scatterlist sg_tx;
89 unsigned int sg_len_tx;
90 struct scatterlist sg_rx[2];
91 size_t buf_len_rx;
92 struct sh_dmae_slave param_tx;
93 struct sh_dmae_slave param_rx;
94 struct work_struct work_tx;
95 struct work_struct work_rx;
96 struct timer_list rx_timer;
97 unsigned int rx_timeout;
98 #endif
99
100 struct notifier_block freq_transition;
101
102 #ifdef CONFIG_SERIAL_SH_SCI_CONSOLE
103 unsigned short saved_smr;
104 unsigned short saved_fcr;
105 unsigned char saved_brr;
106 #endif
107 };
108
109 /* Function prototypes */
110 static void sci_start_tx(struct uart_port *port);
111 static void sci_stop_tx(struct uart_port *port);
112 static void sci_start_rx(struct uart_port *port);
113
114 #define SCI_NPORTS CONFIG_SERIAL_SH_SCI_NR_UARTS
115
116 static struct sci_port sci_ports[SCI_NPORTS];
117 static struct uart_driver sci_uart_driver;
118
119 static inline struct sci_port *
to_sci_port(struct uart_port * uart)120 to_sci_port(struct uart_port *uart)
121 {
122 return container_of(uart, struct sci_port, port);
123 }
124
125 struct plat_sci_reg {
126 u8 offset, size;
127 };
128
129 /* Helper for invalidating specific entries of an inherited map. */
130 #define sci_reg_invalid { .offset = 0, .size = 0 }
131
132 static struct plat_sci_reg sci_regmap[SCIx_NR_REGTYPES][SCIx_NR_REGS] = {
133 [SCIx_PROBE_REGTYPE] = {
134 [0 ... SCIx_NR_REGS - 1] = sci_reg_invalid,
135 },
136
137 /*
138 * Common SCI definitions, dependent on the port's regshift
139 * value.
140 */
141 [SCIx_SCI_REGTYPE] = {
142 [SCSMR] = { 0x00, 8 },
143 [SCBRR] = { 0x01, 8 },
144 [SCSCR] = { 0x02, 8 },
145 [SCxTDR] = { 0x03, 8 },
146 [SCxSR] = { 0x04, 8 },
147 [SCxRDR] = { 0x05, 8 },
148 [SCFCR] = sci_reg_invalid,
149 [SCFDR] = sci_reg_invalid,
150 [SCTFDR] = sci_reg_invalid,
151 [SCRFDR] = sci_reg_invalid,
152 [SCSPTR] = sci_reg_invalid,
153 [SCLSR] = sci_reg_invalid,
154 },
155
156 /*
157 * Common definitions for legacy IrDA ports, dependent on
158 * regshift value.
159 */
160 [SCIx_IRDA_REGTYPE] = {
161 [SCSMR] = { 0x00, 8 },
162 [SCBRR] = { 0x01, 8 },
163 [SCSCR] = { 0x02, 8 },
164 [SCxTDR] = { 0x03, 8 },
165 [SCxSR] = { 0x04, 8 },
166 [SCxRDR] = { 0x05, 8 },
167 [SCFCR] = { 0x06, 8 },
168 [SCFDR] = { 0x07, 16 },
169 [SCTFDR] = sci_reg_invalid,
170 [SCRFDR] = sci_reg_invalid,
171 [SCSPTR] = sci_reg_invalid,
172 [SCLSR] = sci_reg_invalid,
173 },
174
175 /*
176 * Common SCIFA definitions.
177 */
178 [SCIx_SCIFA_REGTYPE] = {
179 [SCSMR] = { 0x00, 16 },
180 [SCBRR] = { 0x04, 8 },
181 [SCSCR] = { 0x08, 16 },
182 [SCxTDR] = { 0x20, 8 },
183 [SCxSR] = { 0x14, 16 },
184 [SCxRDR] = { 0x24, 8 },
185 [SCFCR] = { 0x18, 16 },
186 [SCFDR] = { 0x1c, 16 },
187 [SCTFDR] = sci_reg_invalid,
188 [SCRFDR] = sci_reg_invalid,
189 [SCSPTR] = sci_reg_invalid,
190 [SCLSR] = sci_reg_invalid,
191 },
192
193 /*
194 * Common SCIFB definitions.
195 */
196 [SCIx_SCIFB_REGTYPE] = {
197 [SCSMR] = { 0x00, 16 },
198 [SCBRR] = { 0x04, 8 },
199 [SCSCR] = { 0x08, 16 },
200 [SCxTDR] = { 0x40, 8 },
201 [SCxSR] = { 0x14, 16 },
202 [SCxRDR] = { 0x60, 8 },
203 [SCFCR] = { 0x18, 16 },
204 [SCFDR] = { 0x1c, 16 },
205 [SCTFDR] = sci_reg_invalid,
206 [SCRFDR] = sci_reg_invalid,
207 [SCSPTR] = sci_reg_invalid,
208 [SCLSR] = sci_reg_invalid,
209 },
210
211 /*
212 * Common SH-2(A) SCIF definitions for ports with FIFO data
213 * count registers.
214 */
215 [SCIx_SH2_SCIF_FIFODATA_REGTYPE] = {
216 [SCSMR] = { 0x00, 16 },
217 [SCBRR] = { 0x04, 8 },
218 [SCSCR] = { 0x08, 16 },
219 [SCxTDR] = { 0x0c, 8 },
220 [SCxSR] = { 0x10, 16 },
221 [SCxRDR] = { 0x14, 8 },
222 [SCFCR] = { 0x18, 16 },
223 [SCFDR] = { 0x1c, 16 },
224 [SCTFDR] = sci_reg_invalid,
225 [SCRFDR] = sci_reg_invalid,
226 [SCSPTR] = { 0x20, 16 },
227 [SCLSR] = { 0x24, 16 },
228 },
229
230 /*
231 * Common SH-3 SCIF definitions.
232 */
233 [SCIx_SH3_SCIF_REGTYPE] = {
234 [SCSMR] = { 0x00, 8 },
235 [SCBRR] = { 0x02, 8 },
236 [SCSCR] = { 0x04, 8 },
237 [SCxTDR] = { 0x06, 8 },
238 [SCxSR] = { 0x08, 16 },
239 [SCxRDR] = { 0x0a, 8 },
240 [SCFCR] = { 0x0c, 8 },
241 [SCFDR] = { 0x0e, 16 },
242 [SCTFDR] = sci_reg_invalid,
243 [SCRFDR] = sci_reg_invalid,
244 [SCSPTR] = sci_reg_invalid,
245 [SCLSR] = sci_reg_invalid,
246 },
247
248 /*
249 * Common SH-4(A) SCIF(B) definitions.
250 */
251 [SCIx_SH4_SCIF_REGTYPE] = {
252 [SCSMR] = { 0x00, 16 },
253 [SCBRR] = { 0x04, 8 },
254 [SCSCR] = { 0x08, 16 },
255 [SCxTDR] = { 0x0c, 8 },
256 [SCxSR] = { 0x10, 16 },
257 [SCxRDR] = { 0x14, 8 },
258 [SCFCR] = { 0x18, 16 },
259 [SCFDR] = { 0x1c, 16 },
260 [SCTFDR] = sci_reg_invalid,
261 [SCRFDR] = sci_reg_invalid,
262 [SCSPTR] = { 0x20, 16 },
263 [SCLSR] = { 0x24, 16 },
264 },
265
266 /*
267 * Common SH-4(A) SCIF(B) definitions for ports without an SCSPTR
268 * register.
269 */
270 [SCIx_SH4_SCIF_NO_SCSPTR_REGTYPE] = {
271 [SCSMR] = { 0x00, 16 },
272 [SCBRR] = { 0x04, 8 },
273 [SCSCR] = { 0x08, 16 },
274 [SCxTDR] = { 0x0c, 8 },
275 [SCxSR] = { 0x10, 16 },
276 [SCxRDR] = { 0x14, 8 },
277 [SCFCR] = { 0x18, 16 },
278 [SCFDR] = { 0x1c, 16 },
279 [SCTFDR] = sci_reg_invalid,
280 [SCRFDR] = sci_reg_invalid,
281 [SCSPTR] = sci_reg_invalid,
282 [SCLSR] = { 0x24, 16 },
283 },
284
285 /*
286 * Common SH-4(A) SCIF(B) definitions for ports with FIFO data
287 * count registers.
288 */
289 [SCIx_SH4_SCIF_FIFODATA_REGTYPE] = {
290 [SCSMR] = { 0x00, 16 },
291 [SCBRR] = { 0x04, 8 },
292 [SCSCR] = { 0x08, 16 },
293 [SCxTDR] = { 0x0c, 8 },
294 [SCxSR] = { 0x10, 16 },
295 [SCxRDR] = { 0x14, 8 },
296 [SCFCR] = { 0x18, 16 },
297 [SCFDR] = { 0x1c, 16 },
298 [SCTFDR] = { 0x1c, 16 }, /* aliased to SCFDR */
299 [SCRFDR] = { 0x20, 16 },
300 [SCSPTR] = { 0x24, 16 },
301 [SCLSR] = { 0x28, 16 },
302 },
303
304 /*
305 * SH7705-style SCIF(B) ports, lacking both SCSPTR and SCLSR
306 * registers.
307 */
308 [SCIx_SH7705_SCIF_REGTYPE] = {
309 [SCSMR] = { 0x00, 16 },
310 [SCBRR] = { 0x04, 8 },
311 [SCSCR] = { 0x08, 16 },
312 [SCxTDR] = { 0x20, 8 },
313 [SCxSR] = { 0x14, 16 },
314 [SCxRDR] = { 0x24, 8 },
315 [SCFCR] = { 0x18, 16 },
316 [SCFDR] = { 0x1c, 16 },
317 [SCTFDR] = sci_reg_invalid,
318 [SCRFDR] = sci_reg_invalid,
319 [SCSPTR] = sci_reg_invalid,
320 [SCLSR] = sci_reg_invalid,
321 },
322 };
323
324 #define sci_getreg(up, offset) (sci_regmap[to_sci_port(up)->cfg->regtype] + offset)
325
326 /*
327 * The "offset" here is rather misleading, in that it refers to an enum
328 * value relative to the port mapping rather than the fixed offset
329 * itself, which needs to be manually retrieved from the platform's
330 * register map for the given port.
331 */
sci_serial_in(struct uart_port * p,int offset)332 static unsigned int sci_serial_in(struct uart_port *p, int offset)
333 {
334 struct plat_sci_reg *reg = sci_getreg(p, offset);
335
336 if (reg->size == 8)
337 return ioread8(p->membase + (reg->offset << p->regshift));
338 else if (reg->size == 16)
339 return ioread16(p->membase + (reg->offset << p->regshift));
340 else
341 WARN(1, "Invalid register access\n");
342
343 return 0;
344 }
345
sci_serial_out(struct uart_port * p,int offset,int value)346 static void sci_serial_out(struct uart_port *p, int offset, int value)
347 {
348 struct plat_sci_reg *reg = sci_getreg(p, offset);
349
350 if (reg->size == 8)
351 iowrite8(value, p->membase + (reg->offset << p->regshift));
352 else if (reg->size == 16)
353 iowrite16(value, p->membase + (reg->offset << p->regshift));
354 else
355 WARN(1, "Invalid register access\n");
356 }
357
358 #define sci_in(up, offset) (up->serial_in(up, offset))
359 #define sci_out(up, offset, value) (up->serial_out(up, offset, value))
360
sci_probe_regmap(struct plat_sci_port * cfg)361 static int sci_probe_regmap(struct plat_sci_port *cfg)
362 {
363 switch (cfg->type) {
364 case PORT_SCI:
365 cfg->regtype = SCIx_SCI_REGTYPE;
366 break;
367 case PORT_IRDA:
368 cfg->regtype = SCIx_IRDA_REGTYPE;
369 break;
370 case PORT_SCIFA:
371 cfg->regtype = SCIx_SCIFA_REGTYPE;
372 break;
373 case PORT_SCIFB:
374 cfg->regtype = SCIx_SCIFB_REGTYPE;
375 break;
376 case PORT_SCIF:
377 /*
378 * The SH-4 is a bit of a misnomer here, although that's
379 * where this particular port layout originated. This
380 * configuration (or some slight variation thereof)
381 * remains the dominant model for all SCIFs.
382 */
383 cfg->regtype = SCIx_SH4_SCIF_REGTYPE;
384 break;
385 default:
386 printk(KERN_ERR "Can't probe register map for given port\n");
387 return -EINVAL;
388 }
389
390 return 0;
391 }
392
sci_port_enable(struct sci_port * sci_port)393 static void sci_port_enable(struct sci_port *sci_port)
394 {
395 if (!sci_port->port.dev)
396 return;
397
398 pm_runtime_get_sync(sci_port->port.dev);
399
400 clk_enable(sci_port->iclk);
401 sci_port->port.uartclk = clk_get_rate(sci_port->iclk);
402 clk_enable(sci_port->fclk);
403 }
404
sci_port_disable(struct sci_port * sci_port)405 static void sci_port_disable(struct sci_port *sci_port)
406 {
407 if (!sci_port->port.dev)
408 return;
409
410 clk_disable(sci_port->fclk);
411 clk_disable(sci_port->iclk);
412
413 pm_runtime_put_sync(sci_port->port.dev);
414 }
415
416 #if defined(CONFIG_CONSOLE_POLL) || defined(CONFIG_SERIAL_SH_SCI_CONSOLE)
417
418 #ifdef CONFIG_CONSOLE_POLL
sci_poll_get_char(struct uart_port * port)419 static int sci_poll_get_char(struct uart_port *port)
420 {
421 unsigned short status;
422 int c;
423
424 do {
425 status = sci_in(port, SCxSR);
426 if (status & SCxSR_ERRORS(port)) {
427 sci_out(port, SCxSR, SCxSR_ERROR_CLEAR(port));
428 continue;
429 }
430 break;
431 } while (1);
432
433 if (!(status & SCxSR_RDxF(port)))
434 return NO_POLL_CHAR;
435
436 c = sci_in(port, SCxRDR);
437
438 /* Dummy read */
439 sci_in(port, SCxSR);
440 sci_out(port, SCxSR, SCxSR_RDxF_CLEAR(port));
441
442 return c;
443 }
444 #endif
445
sci_poll_put_char(struct uart_port * port,unsigned char c)446 static void sci_poll_put_char(struct uart_port *port, unsigned char c)
447 {
448 unsigned short status;
449
450 do {
451 status = sci_in(port, SCxSR);
452 } while (!(status & SCxSR_TDxE(port)));
453
454 sci_out(port, SCxTDR, c);
455 sci_out(port, SCxSR, SCxSR_TDxE_CLEAR(port) & ~SCxSR_TEND(port));
456 }
457 #endif /* CONFIG_CONSOLE_POLL || CONFIG_SERIAL_SH_SCI_CONSOLE */
458
sci_init_pins(struct uart_port * port,unsigned int cflag)459 static void sci_init_pins(struct uart_port *port, unsigned int cflag)
460 {
461 struct sci_port *s = to_sci_port(port);
462 struct plat_sci_reg *reg = sci_regmap[s->cfg->regtype] + SCSPTR;
463
464 /*
465 * Use port-specific handler if provided.
466 */
467 if (s->cfg->ops && s->cfg->ops->init_pins) {
468 s->cfg->ops->init_pins(port, cflag);
469 return;
470 }
471
472 /*
473 * For the generic path SCSPTR is necessary. Bail out if that's
474 * unavailable, too.
475 */
476 if (!reg->size)
477 return;
478
479 if ((s->cfg->capabilities & SCIx_HAVE_RTSCTS) &&
480 ((!(cflag & CRTSCTS)))) {
481 unsigned short status;
482
483 status = sci_in(port, SCSPTR);
484 status &= ~SCSPTR_CTSIO;
485 status |= SCSPTR_RTSIO;
486 sci_out(port, SCSPTR, status); /* Set RTS = 1 */
487 }
488 }
489
sci_txfill(struct uart_port * port)490 static int sci_txfill(struct uart_port *port)
491 {
492 struct plat_sci_reg *reg;
493
494 reg = sci_getreg(port, SCTFDR);
495 if (reg->size)
496 return sci_in(port, SCTFDR) & 0xff;
497
498 reg = sci_getreg(port, SCFDR);
499 if (reg->size)
500 return sci_in(port, SCFDR) >> 8;
501
502 return !(sci_in(port, SCxSR) & SCI_TDRE);
503 }
504
sci_txroom(struct uart_port * port)505 static int sci_txroom(struct uart_port *port)
506 {
507 return port->fifosize - sci_txfill(port);
508 }
509
sci_rxfill(struct uart_port * port)510 static int sci_rxfill(struct uart_port *port)
511 {
512 struct plat_sci_reg *reg;
513
514 reg = sci_getreg(port, SCRFDR);
515 if (reg->size)
516 return sci_in(port, SCRFDR) & 0xff;
517
518 reg = sci_getreg(port, SCFDR);
519 if (reg->size)
520 return sci_in(port, SCFDR) & ((port->fifosize << 1) - 1);
521
522 return (sci_in(port, SCxSR) & SCxSR_RDxF(port)) != 0;
523 }
524
525 /*
526 * SCI helper for checking the state of the muxed port/RXD pins.
527 */
sci_rxd_in(struct uart_port * port)528 static inline int sci_rxd_in(struct uart_port *port)
529 {
530 struct sci_port *s = to_sci_port(port);
531
532 if (s->cfg->port_reg <= 0)
533 return 1;
534
535 return !!__raw_readb(s->cfg->port_reg);
536 }
537
538 /* ********************************************************************** *
539 * the interrupt related routines *
540 * ********************************************************************** */
541
sci_transmit_chars(struct uart_port * port)542 static void sci_transmit_chars(struct uart_port *port)
543 {
544 struct circ_buf *xmit = &port->state->xmit;
545 unsigned int stopped = uart_tx_stopped(port);
546 unsigned short status;
547 unsigned short ctrl;
548 int count;
549
550 status = sci_in(port, SCxSR);
551 if (!(status & SCxSR_TDxE(port))) {
552 ctrl = sci_in(port, SCSCR);
553 if (uart_circ_empty(xmit))
554 ctrl &= ~SCSCR_TIE;
555 else
556 ctrl |= SCSCR_TIE;
557 sci_out(port, SCSCR, ctrl);
558 return;
559 }
560
561 count = sci_txroom(port);
562
563 do {
564 unsigned char c;
565
566 if (port->x_char) {
567 c = port->x_char;
568 port->x_char = 0;
569 } else if (!uart_circ_empty(xmit) && !stopped) {
570 c = xmit->buf[xmit->tail];
571 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
572 } else {
573 break;
574 }
575
576 sci_out(port, SCxTDR, c);
577
578 port->icount.tx++;
579 } while (--count > 0);
580
581 sci_out(port, SCxSR, SCxSR_TDxE_CLEAR(port));
582
583 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
584 uart_write_wakeup(port);
585 if (uart_circ_empty(xmit)) {
586 sci_stop_tx(port);
587 } else {
588 ctrl = sci_in(port, SCSCR);
589
590 if (port->type != PORT_SCI) {
591 sci_in(port, SCxSR); /* Dummy read */
592 sci_out(port, SCxSR, SCxSR_TDxE_CLEAR(port));
593 }
594
595 ctrl |= SCSCR_TIE;
596 sci_out(port, SCSCR, ctrl);
597 }
598 }
599
600 /* On SH3, SCIF may read end-of-break as a space->mark char */
601 #define STEPFN(c) ({int __c = (c); (((__c-1)|(__c)) == -1); })
602
sci_receive_chars(struct uart_port * port)603 static void sci_receive_chars(struct uart_port *port)
604 {
605 struct sci_port *sci_port = to_sci_port(port);
606 struct tty_struct *tty = port->state->port.tty;
607 int i, count, copied = 0;
608 unsigned short status;
609 unsigned char flag;
610
611 status = sci_in(port, SCxSR);
612 if (!(status & SCxSR_RDxF(port)))
613 return;
614
615 while (1) {
616 /* Don't copy more bytes than there is room for in the buffer */
617 count = tty_buffer_request_room(tty, sci_rxfill(port));
618
619 /* If for any reason we can't copy more data, we're done! */
620 if (count == 0)
621 break;
622
623 if (port->type == PORT_SCI) {
624 char c = sci_in(port, SCxRDR);
625 if (uart_handle_sysrq_char(port, c) ||
626 sci_port->break_flag)
627 count = 0;
628 else
629 tty_insert_flip_char(tty, c, TTY_NORMAL);
630 } else {
631 for (i = 0; i < count; i++) {
632 char c = sci_in(port, SCxRDR);
633
634 status = sci_in(port, SCxSR);
635 #if defined(CONFIG_CPU_SH3)
636 /* Skip "chars" during break */
637 if (sci_port->break_flag) {
638 if ((c == 0) &&
639 (status & SCxSR_FER(port))) {
640 count--; i--;
641 continue;
642 }
643
644 /* Nonzero => end-of-break */
645 dev_dbg(port->dev, "debounce<%02x>\n", c);
646 sci_port->break_flag = 0;
647
648 if (STEPFN(c)) {
649 count--; i--;
650 continue;
651 }
652 }
653 #endif /* CONFIG_CPU_SH3 */
654 if (uart_handle_sysrq_char(port, c)) {
655 count--; i--;
656 continue;
657 }
658
659 /* Store data and status */
660 if (status & SCxSR_FER(port)) {
661 flag = TTY_FRAME;
662 port->icount.frame++;
663 dev_notice(port->dev, "frame error\n");
664 } else if (status & SCxSR_PER(port)) {
665 flag = TTY_PARITY;
666 port->icount.parity++;
667 dev_notice(port->dev, "parity error\n");
668 } else
669 flag = TTY_NORMAL;
670
671 tty_insert_flip_char(tty, c, flag);
672 }
673 }
674
675 sci_in(port, SCxSR); /* dummy read */
676 sci_out(port, SCxSR, SCxSR_RDxF_CLEAR(port));
677
678 copied += count;
679 port->icount.rx += count;
680 }
681
682 if (copied) {
683 /* Tell the rest of the system the news. New characters! */
684 tty_flip_buffer_push(tty);
685 } else {
686 sci_in(port, SCxSR); /* dummy read */
687 sci_out(port, SCxSR, SCxSR_RDxF_CLEAR(port));
688 }
689 }
690
691 #define SCI_BREAK_JIFFIES (HZ/20)
692
693 /*
694 * The sci generates interrupts during the break,
695 * 1 per millisecond or so during the break period, for 9600 baud.
696 * So dont bother disabling interrupts.
697 * But dont want more than 1 break event.
698 * Use a kernel timer to periodically poll the rx line until
699 * the break is finished.
700 */
sci_schedule_break_timer(struct sci_port * port)701 static inline void sci_schedule_break_timer(struct sci_port *port)
702 {
703 mod_timer(&port->break_timer, jiffies + SCI_BREAK_JIFFIES);
704 }
705
706 /* Ensure that two consecutive samples find the break over. */
sci_break_timer(unsigned long data)707 static void sci_break_timer(unsigned long data)
708 {
709 struct sci_port *port = (struct sci_port *)data;
710
711 sci_port_enable(port);
712
713 if (sci_rxd_in(&port->port) == 0) {
714 port->break_flag = 1;
715 sci_schedule_break_timer(port);
716 } else if (port->break_flag == 1) {
717 /* break is over. */
718 port->break_flag = 2;
719 sci_schedule_break_timer(port);
720 } else
721 port->break_flag = 0;
722
723 sci_port_disable(port);
724 }
725
sci_handle_errors(struct uart_port * port)726 static int sci_handle_errors(struct uart_port *port)
727 {
728 int copied = 0;
729 unsigned short status = sci_in(port, SCxSR);
730 struct tty_struct *tty = port->state->port.tty;
731 struct sci_port *s = to_sci_port(port);
732
733 /*
734 * Handle overruns, if supported.
735 */
736 if (s->cfg->overrun_bit != SCIx_NOT_SUPPORTED) {
737 if (status & (1 << s->cfg->overrun_bit)) {
738 port->icount.overrun++;
739
740 /* overrun error */
741 if (tty_insert_flip_char(tty, 0, TTY_OVERRUN))
742 copied++;
743
744 dev_notice(port->dev, "overrun error");
745 }
746 }
747
748 if (status & SCxSR_FER(port)) {
749 if (sci_rxd_in(port) == 0) {
750 /* Notify of BREAK */
751 struct sci_port *sci_port = to_sci_port(port);
752
753 if (!sci_port->break_flag) {
754 port->icount.brk++;
755
756 sci_port->break_flag = 1;
757 sci_schedule_break_timer(sci_port);
758
759 /* Do sysrq handling. */
760 if (uart_handle_break(port))
761 return 0;
762
763 dev_dbg(port->dev, "BREAK detected\n");
764
765 if (tty_insert_flip_char(tty, 0, TTY_BREAK))
766 copied++;
767 }
768
769 } else {
770 /* frame error */
771 port->icount.frame++;
772
773 if (tty_insert_flip_char(tty, 0, TTY_FRAME))
774 copied++;
775
776 dev_notice(port->dev, "frame error\n");
777 }
778 }
779
780 if (status & SCxSR_PER(port)) {
781 /* parity error */
782 port->icount.parity++;
783
784 if (tty_insert_flip_char(tty, 0, TTY_PARITY))
785 copied++;
786
787 dev_notice(port->dev, "parity error");
788 }
789
790 if (copied)
791 tty_flip_buffer_push(tty);
792
793 return copied;
794 }
795
sci_handle_fifo_overrun(struct uart_port * port)796 static int sci_handle_fifo_overrun(struct uart_port *port)
797 {
798 struct tty_struct *tty = port->state->port.tty;
799 struct sci_port *s = to_sci_port(port);
800 struct plat_sci_reg *reg;
801 int copied = 0;
802
803 reg = sci_getreg(port, SCLSR);
804 if (!reg->size)
805 return 0;
806
807 if ((sci_in(port, SCLSR) & (1 << s->cfg->overrun_bit))) {
808 sci_out(port, SCLSR, 0);
809
810 port->icount.overrun++;
811
812 tty_insert_flip_char(tty, 0, TTY_OVERRUN);
813 tty_flip_buffer_push(tty);
814
815 dev_notice(port->dev, "overrun error\n");
816 copied++;
817 }
818
819 return copied;
820 }
821
sci_handle_breaks(struct uart_port * port)822 static int sci_handle_breaks(struct uart_port *port)
823 {
824 int copied = 0;
825 unsigned short status = sci_in(port, SCxSR);
826 struct tty_struct *tty = port->state->port.tty;
827 struct sci_port *s = to_sci_port(port);
828
829 if (uart_handle_break(port))
830 return 0;
831
832 if (!s->break_flag && status & SCxSR_BRK(port)) {
833 #if defined(CONFIG_CPU_SH3)
834 /* Debounce break */
835 s->break_flag = 1;
836 #endif
837
838 port->icount.brk++;
839
840 /* Notify of BREAK */
841 if (tty_insert_flip_char(tty, 0, TTY_BREAK))
842 copied++;
843
844 dev_dbg(port->dev, "BREAK detected\n");
845 }
846
847 if (copied)
848 tty_flip_buffer_push(tty);
849
850 copied += sci_handle_fifo_overrun(port);
851
852 return copied;
853 }
854
sci_rx_interrupt(int irq,void * ptr)855 static irqreturn_t sci_rx_interrupt(int irq, void *ptr)
856 {
857 #ifdef CONFIG_SERIAL_SH_SCI_DMA
858 struct uart_port *port = ptr;
859 struct sci_port *s = to_sci_port(port);
860
861 if (s->chan_rx) {
862 u16 scr = sci_in(port, SCSCR);
863 u16 ssr = sci_in(port, SCxSR);
864
865 /* Disable future Rx interrupts */
866 if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
867 disable_irq_nosync(irq);
868 scr |= 0x4000;
869 } else {
870 scr &= ~SCSCR_RIE;
871 }
872 sci_out(port, SCSCR, scr);
873 /* Clear current interrupt */
874 sci_out(port, SCxSR, ssr & ~(1 | SCxSR_RDxF(port)));
875 dev_dbg(port->dev, "Rx IRQ %lu: setup t-out in %u jiffies\n",
876 jiffies, s->rx_timeout);
877 mod_timer(&s->rx_timer, jiffies + s->rx_timeout);
878
879 return IRQ_HANDLED;
880 }
881 #endif
882
883 /* I think sci_receive_chars has to be called irrespective
884 * of whether the I_IXOFF is set, otherwise, how is the interrupt
885 * to be disabled?
886 */
887 sci_receive_chars(ptr);
888
889 return IRQ_HANDLED;
890 }
891
sci_tx_interrupt(int irq,void * ptr)892 static irqreturn_t sci_tx_interrupt(int irq, void *ptr)
893 {
894 struct uart_port *port = ptr;
895 unsigned long flags;
896
897 spin_lock_irqsave(&port->lock, flags);
898 sci_transmit_chars(port);
899 spin_unlock_irqrestore(&port->lock, flags);
900
901 return IRQ_HANDLED;
902 }
903
sci_er_interrupt(int irq,void * ptr)904 static irqreturn_t sci_er_interrupt(int irq, void *ptr)
905 {
906 struct uart_port *port = ptr;
907
908 /* Handle errors */
909 if (port->type == PORT_SCI) {
910 if (sci_handle_errors(port)) {
911 /* discard character in rx buffer */
912 sci_in(port, SCxSR);
913 sci_out(port, SCxSR, SCxSR_RDxF_CLEAR(port));
914 }
915 } else {
916 sci_handle_fifo_overrun(port);
917 sci_rx_interrupt(irq, ptr);
918 }
919
920 sci_out(port, SCxSR, SCxSR_ERROR_CLEAR(port));
921
922 /* Kick the transmission */
923 sci_tx_interrupt(irq, ptr);
924
925 return IRQ_HANDLED;
926 }
927
sci_br_interrupt(int irq,void * ptr)928 static irqreturn_t sci_br_interrupt(int irq, void *ptr)
929 {
930 struct uart_port *port = ptr;
931
932 /* Handle BREAKs */
933 sci_handle_breaks(port);
934 sci_out(port, SCxSR, SCxSR_BREAK_CLEAR(port));
935
936 return IRQ_HANDLED;
937 }
938
port_rx_irq_mask(struct uart_port * port)939 static inline unsigned long port_rx_irq_mask(struct uart_port *port)
940 {
941 /*
942 * Not all ports (such as SCIFA) will support REIE. Rather than
943 * special-casing the port type, we check the port initialization
944 * IRQ enable mask to see whether the IRQ is desired at all. If
945 * it's unset, it's logically inferred that there's no point in
946 * testing for it.
947 */
948 return SCSCR_RIE | (to_sci_port(port)->cfg->scscr & SCSCR_REIE);
949 }
950
sci_mpxed_interrupt(int irq,void * ptr)951 static irqreturn_t sci_mpxed_interrupt(int irq, void *ptr)
952 {
953 unsigned short ssr_status, scr_status, err_enabled;
954 struct uart_port *port = ptr;
955 struct sci_port *s = to_sci_port(port);
956 irqreturn_t ret = IRQ_NONE;
957
958 ssr_status = sci_in(port, SCxSR);
959 scr_status = sci_in(port, SCSCR);
960 err_enabled = scr_status & port_rx_irq_mask(port);
961
962 /* Tx Interrupt */
963 if ((ssr_status & SCxSR_TDxE(port)) && (scr_status & SCSCR_TIE) &&
964 !s->chan_tx)
965 ret = sci_tx_interrupt(irq, ptr);
966
967 /*
968 * Rx Interrupt: if we're using DMA, the DMA controller clears RDF /
969 * DR flags
970 */
971 if (((ssr_status & SCxSR_RDxF(port)) || s->chan_rx) &&
972 (scr_status & SCSCR_RIE))
973 ret = sci_rx_interrupt(irq, ptr);
974
975 /* Error Interrupt */
976 if ((ssr_status & SCxSR_ERRORS(port)) && err_enabled)
977 ret = sci_er_interrupt(irq, ptr);
978
979 /* Break Interrupt */
980 if ((ssr_status & SCxSR_BRK(port)) && err_enabled)
981 ret = sci_br_interrupt(irq, ptr);
982
983 return ret;
984 }
985
986 /*
987 * Here we define a transition notifier so that we can update all of our
988 * ports' baud rate when the peripheral clock changes.
989 */
sci_notifier(struct notifier_block * self,unsigned long phase,void * p)990 static int sci_notifier(struct notifier_block *self,
991 unsigned long phase, void *p)
992 {
993 struct sci_port *sci_port;
994 unsigned long flags;
995
996 sci_port = container_of(self, struct sci_port, freq_transition);
997
998 if ((phase == CPUFREQ_POSTCHANGE) ||
999 (phase == CPUFREQ_RESUMECHANGE)) {
1000 struct uart_port *port = &sci_port->port;
1001
1002 spin_lock_irqsave(&port->lock, flags);
1003 port->uartclk = clk_get_rate(sci_port->iclk);
1004 spin_unlock_irqrestore(&port->lock, flags);
1005 }
1006
1007 return NOTIFY_OK;
1008 }
1009
1010 static struct sci_irq_desc {
1011 const char *desc;
1012 irq_handler_t handler;
1013 } sci_irq_desc[] = {
1014 /*
1015 * Split out handlers, the default case.
1016 */
1017 [SCIx_ERI_IRQ] = {
1018 .desc = "rx err",
1019 .handler = sci_er_interrupt,
1020 },
1021
1022 [SCIx_RXI_IRQ] = {
1023 .desc = "rx full",
1024 .handler = sci_rx_interrupt,
1025 },
1026
1027 [SCIx_TXI_IRQ] = {
1028 .desc = "tx empty",
1029 .handler = sci_tx_interrupt,
1030 },
1031
1032 [SCIx_BRI_IRQ] = {
1033 .desc = "break",
1034 .handler = sci_br_interrupt,
1035 },
1036
1037 /*
1038 * Special muxed handler.
1039 */
1040 [SCIx_MUX_IRQ] = {
1041 .desc = "mux",
1042 .handler = sci_mpxed_interrupt,
1043 },
1044 };
1045
sci_request_irq(struct sci_port * port)1046 static int sci_request_irq(struct sci_port *port)
1047 {
1048 struct uart_port *up = &port->port;
1049 int i, j, ret = 0;
1050
1051 for (i = j = 0; i < SCIx_NR_IRQS; i++, j++) {
1052 struct sci_irq_desc *desc;
1053 unsigned int irq;
1054
1055 if (SCIx_IRQ_IS_MUXED(port)) {
1056 i = SCIx_MUX_IRQ;
1057 irq = up->irq;
1058 } else
1059 irq = port->cfg->irqs[i];
1060
1061 desc = sci_irq_desc + i;
1062 port->irqstr[j] = kasprintf(GFP_KERNEL, "%s:%s",
1063 dev_name(up->dev), desc->desc);
1064 if (!port->irqstr[j]) {
1065 dev_err(up->dev, "Failed to allocate %s IRQ string\n",
1066 desc->desc);
1067 goto out_nomem;
1068 }
1069
1070 ret = request_irq(irq, desc->handler, up->irqflags,
1071 port->irqstr[j], port);
1072 if (unlikely(ret)) {
1073 dev_err(up->dev, "Can't allocate %s IRQ\n", desc->desc);
1074 goto out_noirq;
1075 }
1076 }
1077
1078 return 0;
1079
1080 out_noirq:
1081 while (--i >= 0)
1082 free_irq(port->cfg->irqs[i], port);
1083
1084 out_nomem:
1085 while (--j >= 0)
1086 kfree(port->irqstr[j]);
1087
1088 return ret;
1089 }
1090
sci_free_irq(struct sci_port * port)1091 static void sci_free_irq(struct sci_port *port)
1092 {
1093 int i;
1094
1095 /*
1096 * Intentionally in reverse order so we iterate over the muxed
1097 * IRQ first.
1098 */
1099 for (i = 0; i < SCIx_NR_IRQS; i++) {
1100 free_irq(port->cfg->irqs[i], port);
1101 kfree(port->irqstr[i]);
1102
1103 if (SCIx_IRQ_IS_MUXED(port)) {
1104 /* If there's only one IRQ, we're done. */
1105 return;
1106 }
1107 }
1108 }
1109
1110 static const char *sci_gpio_names[SCIx_NR_FNS] = {
1111 "sck", "rxd", "txd", "cts", "rts",
1112 };
1113
sci_gpio_str(unsigned int index)1114 static const char *sci_gpio_str(unsigned int index)
1115 {
1116 return sci_gpio_names[index];
1117 }
1118
sci_init_gpios(struct sci_port * port)1119 static void __devinit sci_init_gpios(struct sci_port *port)
1120 {
1121 struct uart_port *up = &port->port;
1122 int i;
1123
1124 if (!port->cfg)
1125 return;
1126
1127 for (i = 0; i < SCIx_NR_FNS; i++) {
1128 const char *desc;
1129 int ret;
1130
1131 if (!port->cfg->gpios[i])
1132 continue;
1133
1134 desc = sci_gpio_str(i);
1135
1136 port->gpiostr[i] = kasprintf(GFP_KERNEL, "%s:%s",
1137 dev_name(up->dev), desc);
1138
1139 /*
1140 * If we've failed the allocation, we can still continue
1141 * on with a NULL string.
1142 */
1143 if (!port->gpiostr[i])
1144 dev_notice(up->dev, "%s string allocation failure\n",
1145 desc);
1146
1147 ret = gpio_request(port->cfg->gpios[i], port->gpiostr[i]);
1148 if (unlikely(ret != 0)) {
1149 dev_notice(up->dev, "failed %s gpio request\n", desc);
1150
1151 /*
1152 * If we can't get the GPIO for whatever reason,
1153 * no point in keeping the verbose string around.
1154 */
1155 kfree(port->gpiostr[i]);
1156 }
1157 }
1158 }
1159
sci_free_gpios(struct sci_port * port)1160 static void sci_free_gpios(struct sci_port *port)
1161 {
1162 int i;
1163
1164 for (i = 0; i < SCIx_NR_FNS; i++)
1165 if (port->cfg->gpios[i]) {
1166 gpio_free(port->cfg->gpios[i]);
1167 kfree(port->gpiostr[i]);
1168 }
1169 }
1170
sci_tx_empty(struct uart_port * port)1171 static unsigned int sci_tx_empty(struct uart_port *port)
1172 {
1173 unsigned short status = sci_in(port, SCxSR);
1174 unsigned short in_tx_fifo = sci_txfill(port);
1175
1176 return (status & SCxSR_TEND(port)) && !in_tx_fifo ? TIOCSER_TEMT : 0;
1177 }
1178
1179 /*
1180 * Modem control is a bit of a mixed bag for SCI(F) ports. Generally
1181 * CTS/RTS is supported in hardware by at least one port and controlled
1182 * via SCSPTR (SCxPCR for SCIFA/B parts), or external pins (presently
1183 * handled via the ->init_pins() op, which is a bit of a one-way street,
1184 * lacking any ability to defer pin control -- this will later be
1185 * converted over to the GPIO framework).
1186 *
1187 * Other modes (such as loopback) are supported generically on certain
1188 * port types, but not others. For these it's sufficient to test for the
1189 * existence of the support register and simply ignore the port type.
1190 */
sci_set_mctrl(struct uart_port * port,unsigned int mctrl)1191 static void sci_set_mctrl(struct uart_port *port, unsigned int mctrl)
1192 {
1193 if (mctrl & TIOCM_LOOP) {
1194 struct plat_sci_reg *reg;
1195
1196 /*
1197 * Standard loopback mode for SCFCR ports.
1198 */
1199 reg = sci_getreg(port, SCFCR);
1200 if (reg->size)
1201 sci_out(port, SCFCR, sci_in(port, SCFCR) | 1);
1202 }
1203 }
1204
sci_get_mctrl(struct uart_port * port)1205 static unsigned int sci_get_mctrl(struct uart_port *port)
1206 {
1207 /*
1208 * CTS/RTS is handled in hardware when supported, while nothing
1209 * else is wired up. Keep it simple and simply assert DSR/CAR.
1210 */
1211 return TIOCM_DSR | TIOCM_CAR;
1212 }
1213
1214 #ifdef CONFIG_SERIAL_SH_SCI_DMA
sci_dma_tx_complete(void * arg)1215 static void sci_dma_tx_complete(void *arg)
1216 {
1217 struct sci_port *s = arg;
1218 struct uart_port *port = &s->port;
1219 struct circ_buf *xmit = &port->state->xmit;
1220 unsigned long flags;
1221
1222 dev_dbg(port->dev, "%s(%d)\n", __func__, port->line);
1223
1224 spin_lock_irqsave(&port->lock, flags);
1225
1226 xmit->tail += sg_dma_len(&s->sg_tx);
1227 xmit->tail &= UART_XMIT_SIZE - 1;
1228
1229 port->icount.tx += sg_dma_len(&s->sg_tx);
1230
1231 async_tx_ack(s->desc_tx);
1232 s->cookie_tx = -EINVAL;
1233 s->desc_tx = NULL;
1234
1235 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
1236 uart_write_wakeup(port);
1237
1238 if (!uart_circ_empty(xmit)) {
1239 schedule_work(&s->work_tx);
1240 } else if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
1241 u16 ctrl = sci_in(port, SCSCR);
1242 sci_out(port, SCSCR, ctrl & ~SCSCR_TIE);
1243 }
1244
1245 spin_unlock_irqrestore(&port->lock, flags);
1246 }
1247
1248 /* Locking: called with port lock held */
sci_dma_rx_push(struct sci_port * s,struct tty_struct * tty,size_t count)1249 static int sci_dma_rx_push(struct sci_port *s, struct tty_struct *tty,
1250 size_t count)
1251 {
1252 struct uart_port *port = &s->port;
1253 int i, active, room;
1254
1255 room = tty_buffer_request_room(tty, count);
1256
1257 if (s->active_rx == s->cookie_rx[0]) {
1258 active = 0;
1259 } else if (s->active_rx == s->cookie_rx[1]) {
1260 active = 1;
1261 } else {
1262 dev_err(port->dev, "cookie %d not found!\n", s->active_rx);
1263 return 0;
1264 }
1265
1266 if (room < count)
1267 dev_warn(port->dev, "Rx overrun: dropping %u bytes\n",
1268 count - room);
1269 if (!room)
1270 return room;
1271
1272 for (i = 0; i < room; i++)
1273 tty_insert_flip_char(tty, ((u8 *)sg_virt(&s->sg_rx[active]))[i],
1274 TTY_NORMAL);
1275
1276 port->icount.rx += room;
1277
1278 return room;
1279 }
1280
sci_dma_rx_complete(void * arg)1281 static void sci_dma_rx_complete(void *arg)
1282 {
1283 struct sci_port *s = arg;
1284 struct uart_port *port = &s->port;
1285 struct tty_struct *tty = port->state->port.tty;
1286 unsigned long flags;
1287 int count;
1288
1289 dev_dbg(port->dev, "%s(%d) active #%d\n", __func__, port->line, s->active_rx);
1290
1291 spin_lock_irqsave(&port->lock, flags);
1292
1293 count = sci_dma_rx_push(s, tty, s->buf_len_rx);
1294
1295 mod_timer(&s->rx_timer, jiffies + s->rx_timeout);
1296
1297 spin_unlock_irqrestore(&port->lock, flags);
1298
1299 if (count)
1300 tty_flip_buffer_push(tty);
1301
1302 schedule_work(&s->work_rx);
1303 }
1304
sci_rx_dma_release(struct sci_port * s,bool enable_pio)1305 static void sci_rx_dma_release(struct sci_port *s, bool enable_pio)
1306 {
1307 struct dma_chan *chan = s->chan_rx;
1308 struct uart_port *port = &s->port;
1309
1310 s->chan_rx = NULL;
1311 s->cookie_rx[0] = s->cookie_rx[1] = -EINVAL;
1312 dma_release_channel(chan);
1313 if (sg_dma_address(&s->sg_rx[0]))
1314 dma_free_coherent(port->dev, s->buf_len_rx * 2,
1315 sg_virt(&s->sg_rx[0]), sg_dma_address(&s->sg_rx[0]));
1316 if (enable_pio)
1317 sci_start_rx(port);
1318 }
1319
sci_tx_dma_release(struct sci_port * s,bool enable_pio)1320 static void sci_tx_dma_release(struct sci_port *s, bool enable_pio)
1321 {
1322 struct dma_chan *chan = s->chan_tx;
1323 struct uart_port *port = &s->port;
1324
1325 s->chan_tx = NULL;
1326 s->cookie_tx = -EINVAL;
1327 dma_release_channel(chan);
1328 if (enable_pio)
1329 sci_start_tx(port);
1330 }
1331
sci_submit_rx(struct sci_port * s)1332 static void sci_submit_rx(struct sci_port *s)
1333 {
1334 struct dma_chan *chan = s->chan_rx;
1335 int i;
1336
1337 for (i = 0; i < 2; i++) {
1338 struct scatterlist *sg = &s->sg_rx[i];
1339 struct dma_async_tx_descriptor *desc;
1340
1341 desc = chan->device->device_prep_slave_sg(chan,
1342 sg, 1, DMA_DEV_TO_MEM, DMA_PREP_INTERRUPT);
1343
1344 if (desc) {
1345 s->desc_rx[i] = desc;
1346 desc->callback = sci_dma_rx_complete;
1347 desc->callback_param = s;
1348 s->cookie_rx[i] = desc->tx_submit(desc);
1349 }
1350
1351 if (!desc || s->cookie_rx[i] < 0) {
1352 if (i) {
1353 async_tx_ack(s->desc_rx[0]);
1354 s->cookie_rx[0] = -EINVAL;
1355 }
1356 if (desc) {
1357 async_tx_ack(desc);
1358 s->cookie_rx[i] = -EINVAL;
1359 }
1360 dev_warn(s->port.dev,
1361 "failed to re-start DMA, using PIO\n");
1362 sci_rx_dma_release(s, true);
1363 return;
1364 }
1365 dev_dbg(s->port.dev, "%s(): cookie %d to #%d\n", __func__,
1366 s->cookie_rx[i], i);
1367 }
1368
1369 s->active_rx = s->cookie_rx[0];
1370
1371 dma_async_issue_pending(chan);
1372 }
1373
work_fn_rx(struct work_struct * work)1374 static void work_fn_rx(struct work_struct *work)
1375 {
1376 struct sci_port *s = container_of(work, struct sci_port, work_rx);
1377 struct uart_port *port = &s->port;
1378 struct dma_async_tx_descriptor *desc;
1379 int new;
1380
1381 if (s->active_rx == s->cookie_rx[0]) {
1382 new = 0;
1383 } else if (s->active_rx == s->cookie_rx[1]) {
1384 new = 1;
1385 } else {
1386 dev_err(port->dev, "cookie %d not found!\n", s->active_rx);
1387 return;
1388 }
1389 desc = s->desc_rx[new];
1390
1391 if (dma_async_is_tx_complete(s->chan_rx, s->active_rx, NULL, NULL) !=
1392 DMA_SUCCESS) {
1393 /* Handle incomplete DMA receive */
1394 struct tty_struct *tty = port->state->port.tty;
1395 struct dma_chan *chan = s->chan_rx;
1396 struct sh_desc *sh_desc = container_of(desc, struct sh_desc,
1397 async_tx);
1398 unsigned long flags;
1399 int count;
1400
1401 chan->device->device_control(chan, DMA_TERMINATE_ALL, 0);
1402 dev_dbg(port->dev, "Read %u bytes with cookie %d\n",
1403 sh_desc->partial, sh_desc->cookie);
1404
1405 spin_lock_irqsave(&port->lock, flags);
1406 count = sci_dma_rx_push(s, tty, sh_desc->partial);
1407 spin_unlock_irqrestore(&port->lock, flags);
1408
1409 if (count)
1410 tty_flip_buffer_push(tty);
1411
1412 sci_submit_rx(s);
1413
1414 return;
1415 }
1416
1417 s->cookie_rx[new] = desc->tx_submit(desc);
1418 if (s->cookie_rx[new] < 0) {
1419 dev_warn(port->dev, "Failed submitting Rx DMA descriptor\n");
1420 sci_rx_dma_release(s, true);
1421 return;
1422 }
1423
1424 s->active_rx = s->cookie_rx[!new];
1425
1426 dev_dbg(port->dev, "%s: cookie %d #%d, new active #%d\n", __func__,
1427 s->cookie_rx[new], new, s->active_rx);
1428 }
1429
work_fn_tx(struct work_struct * work)1430 static void work_fn_tx(struct work_struct *work)
1431 {
1432 struct sci_port *s = container_of(work, struct sci_port, work_tx);
1433 struct dma_async_tx_descriptor *desc;
1434 struct dma_chan *chan = s->chan_tx;
1435 struct uart_port *port = &s->port;
1436 struct circ_buf *xmit = &port->state->xmit;
1437 struct scatterlist *sg = &s->sg_tx;
1438
1439 /*
1440 * DMA is idle now.
1441 * Port xmit buffer is already mapped, and it is one page... Just adjust
1442 * offsets and lengths. Since it is a circular buffer, we have to
1443 * transmit till the end, and then the rest. Take the port lock to get a
1444 * consistent xmit buffer state.
1445 */
1446 spin_lock_irq(&port->lock);
1447 sg->offset = xmit->tail & (UART_XMIT_SIZE - 1);
1448 sg_dma_address(sg) = (sg_dma_address(sg) & ~(UART_XMIT_SIZE - 1)) +
1449 sg->offset;
1450 sg_dma_len(sg) = min((int)CIRC_CNT(xmit->head, xmit->tail, UART_XMIT_SIZE),
1451 CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE));
1452 spin_unlock_irq(&port->lock);
1453
1454 BUG_ON(!sg_dma_len(sg));
1455
1456 desc = chan->device->device_prep_slave_sg(chan,
1457 sg, s->sg_len_tx, DMA_MEM_TO_DEV,
1458 DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1459 if (!desc) {
1460 /* switch to PIO */
1461 sci_tx_dma_release(s, true);
1462 return;
1463 }
1464
1465 dma_sync_sg_for_device(port->dev, sg, 1, DMA_TO_DEVICE);
1466
1467 spin_lock_irq(&port->lock);
1468 s->desc_tx = desc;
1469 desc->callback = sci_dma_tx_complete;
1470 desc->callback_param = s;
1471 spin_unlock_irq(&port->lock);
1472 s->cookie_tx = desc->tx_submit(desc);
1473 if (s->cookie_tx < 0) {
1474 dev_warn(port->dev, "Failed submitting Tx DMA descriptor\n");
1475 /* switch to PIO */
1476 sci_tx_dma_release(s, true);
1477 return;
1478 }
1479
1480 dev_dbg(port->dev, "%s: %p: %d...%d, cookie %d\n", __func__,
1481 xmit->buf, xmit->tail, xmit->head, s->cookie_tx);
1482
1483 dma_async_issue_pending(chan);
1484 }
1485 #endif
1486
sci_start_tx(struct uart_port * port)1487 static void sci_start_tx(struct uart_port *port)
1488 {
1489 struct sci_port *s = to_sci_port(port);
1490 unsigned short ctrl;
1491
1492 #ifdef CONFIG_SERIAL_SH_SCI_DMA
1493 if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
1494 u16 new, scr = sci_in(port, SCSCR);
1495 if (s->chan_tx)
1496 new = scr | 0x8000;
1497 else
1498 new = scr & ~0x8000;
1499 if (new != scr)
1500 sci_out(port, SCSCR, new);
1501 }
1502
1503 if (s->chan_tx && !uart_circ_empty(&s->port.state->xmit) &&
1504 s->cookie_tx < 0)
1505 schedule_work(&s->work_tx);
1506 #endif
1507
1508 if (!s->chan_tx || port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
1509 /* Set TIE (Transmit Interrupt Enable) bit in SCSCR */
1510 ctrl = sci_in(port, SCSCR);
1511 sci_out(port, SCSCR, ctrl | SCSCR_TIE);
1512 }
1513 }
1514
sci_stop_tx(struct uart_port * port)1515 static void sci_stop_tx(struct uart_port *port)
1516 {
1517 unsigned short ctrl;
1518
1519 /* Clear TIE (Transmit Interrupt Enable) bit in SCSCR */
1520 ctrl = sci_in(port, SCSCR);
1521
1522 if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
1523 ctrl &= ~0x8000;
1524
1525 ctrl &= ~SCSCR_TIE;
1526
1527 sci_out(port, SCSCR, ctrl);
1528 }
1529
sci_start_rx(struct uart_port * port)1530 static void sci_start_rx(struct uart_port *port)
1531 {
1532 unsigned short ctrl;
1533
1534 ctrl = sci_in(port, SCSCR) | port_rx_irq_mask(port);
1535
1536 if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
1537 ctrl &= ~0x4000;
1538
1539 sci_out(port, SCSCR, ctrl);
1540 }
1541
sci_stop_rx(struct uart_port * port)1542 static void sci_stop_rx(struct uart_port *port)
1543 {
1544 unsigned short ctrl;
1545
1546 ctrl = sci_in(port, SCSCR);
1547
1548 if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
1549 ctrl &= ~0x4000;
1550
1551 ctrl &= ~port_rx_irq_mask(port);
1552
1553 sci_out(port, SCSCR, ctrl);
1554 }
1555
sci_enable_ms(struct uart_port * port)1556 static void sci_enable_ms(struct uart_port *port)
1557 {
1558 /*
1559 * Not supported by hardware, always a nop.
1560 */
1561 }
1562
sci_break_ctl(struct uart_port * port,int break_state)1563 static void sci_break_ctl(struct uart_port *port, int break_state)
1564 {
1565 /*
1566 * Not supported by hardware. Most parts couple break and rx
1567 * interrupts together, with break detection always enabled.
1568 */
1569 }
1570
1571 #ifdef CONFIG_SERIAL_SH_SCI_DMA
filter(struct dma_chan * chan,void * slave)1572 static bool filter(struct dma_chan *chan, void *slave)
1573 {
1574 struct sh_dmae_slave *param = slave;
1575
1576 dev_dbg(chan->device->dev, "%s: slave ID %d\n", __func__,
1577 param->slave_id);
1578
1579 chan->private = param;
1580 return true;
1581 }
1582
rx_timer_fn(unsigned long arg)1583 static void rx_timer_fn(unsigned long arg)
1584 {
1585 struct sci_port *s = (struct sci_port *)arg;
1586 struct uart_port *port = &s->port;
1587 u16 scr = sci_in(port, SCSCR);
1588
1589 if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
1590 scr &= ~0x4000;
1591 enable_irq(s->cfg->irqs[1]);
1592 }
1593 sci_out(port, SCSCR, scr | SCSCR_RIE);
1594 dev_dbg(port->dev, "DMA Rx timed out\n");
1595 schedule_work(&s->work_rx);
1596 }
1597
sci_request_dma(struct uart_port * port)1598 static void sci_request_dma(struct uart_port *port)
1599 {
1600 struct sci_port *s = to_sci_port(port);
1601 struct sh_dmae_slave *param;
1602 struct dma_chan *chan;
1603 dma_cap_mask_t mask;
1604 int nent;
1605
1606 dev_dbg(port->dev, "%s: port %d\n", __func__,
1607 port->line);
1608
1609 if (s->cfg->dma_slave_tx <= 0 || s->cfg->dma_slave_rx <= 0)
1610 return;
1611
1612 dma_cap_zero(mask);
1613 dma_cap_set(DMA_SLAVE, mask);
1614
1615 param = &s->param_tx;
1616
1617 /* Slave ID, e.g., SHDMA_SLAVE_SCIF0_TX */
1618 param->slave_id = s->cfg->dma_slave_tx;
1619
1620 s->cookie_tx = -EINVAL;
1621 chan = dma_request_channel(mask, filter, param);
1622 dev_dbg(port->dev, "%s: TX: got channel %p\n", __func__, chan);
1623 if (chan) {
1624 s->chan_tx = chan;
1625 sg_init_table(&s->sg_tx, 1);
1626 /* UART circular tx buffer is an aligned page. */
1627 BUG_ON((int)port->state->xmit.buf & ~PAGE_MASK);
1628 sg_set_page(&s->sg_tx, virt_to_page(port->state->xmit.buf),
1629 UART_XMIT_SIZE, (int)port->state->xmit.buf & ~PAGE_MASK);
1630 nent = dma_map_sg(port->dev, &s->sg_tx, 1, DMA_TO_DEVICE);
1631 if (!nent)
1632 sci_tx_dma_release(s, false);
1633 else
1634 dev_dbg(port->dev, "%s: mapped %d@%p to %x\n", __func__,
1635 sg_dma_len(&s->sg_tx),
1636 port->state->xmit.buf, sg_dma_address(&s->sg_tx));
1637
1638 s->sg_len_tx = nent;
1639
1640 INIT_WORK(&s->work_tx, work_fn_tx);
1641 }
1642
1643 param = &s->param_rx;
1644
1645 /* Slave ID, e.g., SHDMA_SLAVE_SCIF0_RX */
1646 param->slave_id = s->cfg->dma_slave_rx;
1647
1648 chan = dma_request_channel(mask, filter, param);
1649 dev_dbg(port->dev, "%s: RX: got channel %p\n", __func__, chan);
1650 if (chan) {
1651 dma_addr_t dma[2];
1652 void *buf[2];
1653 int i;
1654
1655 s->chan_rx = chan;
1656
1657 s->buf_len_rx = 2 * max(16, (int)port->fifosize);
1658 buf[0] = dma_alloc_coherent(port->dev, s->buf_len_rx * 2,
1659 &dma[0], GFP_KERNEL);
1660
1661 if (!buf[0]) {
1662 dev_warn(port->dev,
1663 "failed to allocate dma buffer, using PIO\n");
1664 sci_rx_dma_release(s, true);
1665 return;
1666 }
1667
1668 buf[1] = buf[0] + s->buf_len_rx;
1669 dma[1] = dma[0] + s->buf_len_rx;
1670
1671 for (i = 0; i < 2; i++) {
1672 struct scatterlist *sg = &s->sg_rx[i];
1673
1674 sg_init_table(sg, 1);
1675 sg_set_page(sg, virt_to_page(buf[i]), s->buf_len_rx,
1676 (int)buf[i] & ~PAGE_MASK);
1677 sg_dma_address(sg) = dma[i];
1678 }
1679
1680 INIT_WORK(&s->work_rx, work_fn_rx);
1681 setup_timer(&s->rx_timer, rx_timer_fn, (unsigned long)s);
1682
1683 sci_submit_rx(s);
1684 }
1685 }
1686
sci_free_dma(struct uart_port * port)1687 static void sci_free_dma(struct uart_port *port)
1688 {
1689 struct sci_port *s = to_sci_port(port);
1690
1691 if (s->chan_tx)
1692 sci_tx_dma_release(s, false);
1693 if (s->chan_rx)
1694 sci_rx_dma_release(s, false);
1695 }
1696 #else
sci_request_dma(struct uart_port * port)1697 static inline void sci_request_dma(struct uart_port *port)
1698 {
1699 }
1700
sci_free_dma(struct uart_port * port)1701 static inline void sci_free_dma(struct uart_port *port)
1702 {
1703 }
1704 #endif
1705
sci_startup(struct uart_port * port)1706 static int sci_startup(struct uart_port *port)
1707 {
1708 struct sci_port *s = to_sci_port(port);
1709 int ret;
1710
1711 dev_dbg(port->dev, "%s(%d)\n", __func__, port->line);
1712
1713 pm_runtime_put_noidle(port->dev);
1714
1715 sci_port_enable(s);
1716
1717 ret = sci_request_irq(s);
1718 if (unlikely(ret < 0))
1719 return ret;
1720
1721 sci_request_dma(port);
1722
1723 sci_start_tx(port);
1724 sci_start_rx(port);
1725
1726 return 0;
1727 }
1728
sci_shutdown(struct uart_port * port)1729 static void sci_shutdown(struct uart_port *port)
1730 {
1731 struct sci_port *s = to_sci_port(port);
1732
1733 dev_dbg(port->dev, "%s(%d)\n", __func__, port->line);
1734
1735 sci_stop_rx(port);
1736 sci_stop_tx(port);
1737
1738 sci_free_dma(port);
1739 sci_free_irq(s);
1740
1741 sci_port_disable(s);
1742
1743 pm_runtime_get_noresume(port->dev);
1744 }
1745
sci_scbrr_calc(unsigned int algo_id,unsigned int bps,unsigned long freq)1746 static unsigned int sci_scbrr_calc(unsigned int algo_id, unsigned int bps,
1747 unsigned long freq)
1748 {
1749 switch (algo_id) {
1750 case SCBRR_ALGO_1:
1751 return ((freq + 16 * bps) / (16 * bps) - 1);
1752 case SCBRR_ALGO_2:
1753 return ((freq + 16 * bps) / (32 * bps) - 1);
1754 case SCBRR_ALGO_3:
1755 return (((freq * 2) + 16 * bps) / (16 * bps) - 1);
1756 case SCBRR_ALGO_4:
1757 return (((freq * 2) + 16 * bps) / (32 * bps) - 1);
1758 case SCBRR_ALGO_5:
1759 return (((freq * 1000 / 32) / bps) - 1);
1760 }
1761
1762 /* Warn, but use a safe default */
1763 WARN_ON(1);
1764
1765 return ((freq + 16 * bps) / (32 * bps) - 1);
1766 }
1767
sci_reset(struct uart_port * port)1768 static void sci_reset(struct uart_port *port)
1769 {
1770 struct plat_sci_reg *reg;
1771 unsigned int status;
1772
1773 do {
1774 status = sci_in(port, SCxSR);
1775 } while (!(status & SCxSR_TEND(port)));
1776
1777 sci_out(port, SCSCR, 0x00); /* TE=0, RE=0, CKE1=0 */
1778
1779 reg = sci_getreg(port, SCFCR);
1780 if (reg->size)
1781 sci_out(port, SCFCR, SCFCR_RFRST | SCFCR_TFRST);
1782 }
1783
sci_set_termios(struct uart_port * port,struct ktermios * termios,struct ktermios * old)1784 static void sci_set_termios(struct uart_port *port, struct ktermios *termios,
1785 struct ktermios *old)
1786 {
1787 struct sci_port *s = to_sci_port(port);
1788 struct plat_sci_reg *reg;
1789 unsigned int baud, smr_val, max_baud;
1790 int t = -1;
1791
1792 /*
1793 * earlyprintk comes here early on with port->uartclk set to zero.
1794 * the clock framework is not up and running at this point so here
1795 * we assume that 115200 is the maximum baud rate. please note that
1796 * the baud rate is not programmed during earlyprintk - it is assumed
1797 * that the previous boot loader has enabled required clocks and
1798 * setup the baud rate generator hardware for us already.
1799 */
1800 max_baud = port->uartclk ? port->uartclk / 16 : 115200;
1801
1802 baud = uart_get_baud_rate(port, termios, old, 0, max_baud);
1803 if (likely(baud && port->uartclk))
1804 t = sci_scbrr_calc(s->cfg->scbrr_algo_id, baud, port->uartclk);
1805
1806 sci_port_enable(s);
1807
1808 sci_reset(port);
1809
1810 smr_val = sci_in(port, SCSMR) & 3;
1811
1812 if ((termios->c_cflag & CSIZE) == CS7)
1813 smr_val |= 0x40;
1814 if (termios->c_cflag & PARENB)
1815 smr_val |= 0x20;
1816 if (termios->c_cflag & PARODD)
1817 smr_val |= 0x30;
1818 if (termios->c_cflag & CSTOPB)
1819 smr_val |= 0x08;
1820
1821 uart_update_timeout(port, termios->c_cflag, baud);
1822
1823 sci_out(port, SCSMR, smr_val);
1824
1825 dev_dbg(port->dev, "%s: SMR %x, t %x, SCSCR %x\n", __func__, smr_val, t,
1826 s->cfg->scscr);
1827
1828 if (t > 0) {
1829 if (t >= 256) {
1830 sci_out(port, SCSMR, (sci_in(port, SCSMR) & ~3) | 1);
1831 t >>= 2;
1832 } else
1833 sci_out(port, SCSMR, sci_in(port, SCSMR) & ~3);
1834
1835 sci_out(port, SCBRR, t);
1836 udelay((1000000+(baud-1)) / baud); /* Wait one bit interval */
1837 }
1838
1839 sci_init_pins(port, termios->c_cflag);
1840
1841 reg = sci_getreg(port, SCFCR);
1842 if (reg->size) {
1843 unsigned short ctrl = sci_in(port, SCFCR);
1844
1845 if (s->cfg->capabilities & SCIx_HAVE_RTSCTS) {
1846 if (termios->c_cflag & CRTSCTS)
1847 ctrl |= SCFCR_MCE;
1848 else
1849 ctrl &= ~SCFCR_MCE;
1850 }
1851
1852 /*
1853 * As we've done a sci_reset() above, ensure we don't
1854 * interfere with the FIFOs while toggling MCE. As the
1855 * reset values could still be set, simply mask them out.
1856 */
1857 ctrl &= ~(SCFCR_RFRST | SCFCR_TFRST);
1858
1859 sci_out(port, SCFCR, ctrl);
1860 }
1861
1862 sci_out(port, SCSCR, s->cfg->scscr);
1863
1864 #ifdef CONFIG_SERIAL_SH_SCI_DMA
1865 /*
1866 * Calculate delay for 1.5 DMA buffers: see
1867 * drivers/serial/serial_core.c::uart_update_timeout(). With 10 bits
1868 * (CS8), 250Hz, 115200 baud and 64 bytes FIFO, the above function
1869 * calculates 1 jiffie for the data plus 5 jiffies for the "slop(e)."
1870 * Then below we calculate 3 jiffies (12ms) for 1.5 DMA buffers (3 FIFO
1871 * sizes), but it has been found out experimentally, that this is not
1872 * enough: the driver too often needlessly runs on a DMA timeout. 20ms
1873 * as a minimum seem to work perfectly.
1874 */
1875 if (s->chan_rx) {
1876 s->rx_timeout = (port->timeout - HZ / 50) * s->buf_len_rx * 3 /
1877 port->fifosize / 2;
1878 dev_dbg(port->dev,
1879 "DMA Rx t-out %ums, tty t-out %u jiffies\n",
1880 s->rx_timeout * 1000 / HZ, port->timeout);
1881 if (s->rx_timeout < msecs_to_jiffies(20))
1882 s->rx_timeout = msecs_to_jiffies(20);
1883 }
1884 #endif
1885
1886 if ((termios->c_cflag & CREAD) != 0)
1887 sci_start_rx(port);
1888
1889 sci_port_disable(s);
1890 }
1891
sci_type(struct uart_port * port)1892 static const char *sci_type(struct uart_port *port)
1893 {
1894 switch (port->type) {
1895 case PORT_IRDA:
1896 return "irda";
1897 case PORT_SCI:
1898 return "sci";
1899 case PORT_SCIF:
1900 return "scif";
1901 case PORT_SCIFA:
1902 return "scifa";
1903 case PORT_SCIFB:
1904 return "scifb";
1905 }
1906
1907 return NULL;
1908 }
1909
sci_port_size(struct uart_port * port)1910 static inline unsigned long sci_port_size(struct uart_port *port)
1911 {
1912 /*
1913 * Pick an arbitrary size that encapsulates all of the base
1914 * registers by default. This can be optimized later, or derived
1915 * from platform resource data at such a time that ports begin to
1916 * behave more erratically.
1917 */
1918 return 64;
1919 }
1920
sci_remap_port(struct uart_port * port)1921 static int sci_remap_port(struct uart_port *port)
1922 {
1923 unsigned long size = sci_port_size(port);
1924
1925 /*
1926 * Nothing to do if there's already an established membase.
1927 */
1928 if (port->membase)
1929 return 0;
1930
1931 if (port->flags & UPF_IOREMAP) {
1932 port->membase = ioremap_nocache(port->mapbase, size);
1933 if (unlikely(!port->membase)) {
1934 dev_err(port->dev, "can't remap port#%d\n", port->line);
1935 return -ENXIO;
1936 }
1937 } else {
1938 /*
1939 * For the simple (and majority of) cases where we don't
1940 * need to do any remapping, just cast the cookie
1941 * directly.
1942 */
1943 port->membase = (void __iomem *)port->mapbase;
1944 }
1945
1946 return 0;
1947 }
1948
sci_release_port(struct uart_port * port)1949 static void sci_release_port(struct uart_port *port)
1950 {
1951 if (port->flags & UPF_IOREMAP) {
1952 iounmap(port->membase);
1953 port->membase = NULL;
1954 }
1955
1956 release_mem_region(port->mapbase, sci_port_size(port));
1957 }
1958
sci_request_port(struct uart_port * port)1959 static int sci_request_port(struct uart_port *port)
1960 {
1961 unsigned long size = sci_port_size(port);
1962 struct resource *res;
1963 int ret;
1964
1965 res = request_mem_region(port->mapbase, size, dev_name(port->dev));
1966 if (unlikely(res == NULL))
1967 return -EBUSY;
1968
1969 ret = sci_remap_port(port);
1970 if (unlikely(ret != 0)) {
1971 release_resource(res);
1972 return ret;
1973 }
1974
1975 return 0;
1976 }
1977
sci_config_port(struct uart_port * port,int flags)1978 static void sci_config_port(struct uart_port *port, int flags)
1979 {
1980 if (flags & UART_CONFIG_TYPE) {
1981 struct sci_port *sport = to_sci_port(port);
1982
1983 port->type = sport->cfg->type;
1984 sci_request_port(port);
1985 }
1986 }
1987
sci_verify_port(struct uart_port * port,struct serial_struct * ser)1988 static int sci_verify_port(struct uart_port *port, struct serial_struct *ser)
1989 {
1990 struct sci_port *s = to_sci_port(port);
1991
1992 if (ser->irq != s->cfg->irqs[SCIx_TXI_IRQ] || ser->irq > nr_irqs)
1993 return -EINVAL;
1994 if (ser->baud_base < 2400)
1995 /* No paper tape reader for Mitch.. */
1996 return -EINVAL;
1997
1998 return 0;
1999 }
2000
2001 static struct uart_ops sci_uart_ops = {
2002 .tx_empty = sci_tx_empty,
2003 .set_mctrl = sci_set_mctrl,
2004 .get_mctrl = sci_get_mctrl,
2005 .start_tx = sci_start_tx,
2006 .stop_tx = sci_stop_tx,
2007 .stop_rx = sci_stop_rx,
2008 .enable_ms = sci_enable_ms,
2009 .break_ctl = sci_break_ctl,
2010 .startup = sci_startup,
2011 .shutdown = sci_shutdown,
2012 .set_termios = sci_set_termios,
2013 .type = sci_type,
2014 .release_port = sci_release_port,
2015 .request_port = sci_request_port,
2016 .config_port = sci_config_port,
2017 .verify_port = sci_verify_port,
2018 #ifdef CONFIG_CONSOLE_POLL
2019 .poll_get_char = sci_poll_get_char,
2020 .poll_put_char = sci_poll_put_char,
2021 #endif
2022 };
2023
sci_init_single(struct platform_device * dev,struct sci_port * sci_port,unsigned int index,struct plat_sci_port * p)2024 static int __devinit sci_init_single(struct platform_device *dev,
2025 struct sci_port *sci_port,
2026 unsigned int index,
2027 struct plat_sci_port *p)
2028 {
2029 struct uart_port *port = &sci_port->port;
2030 int ret;
2031
2032 sci_port->cfg = p;
2033
2034 port->ops = &sci_uart_ops;
2035 port->iotype = UPIO_MEM;
2036 port->line = index;
2037
2038 switch (p->type) {
2039 case PORT_SCIFB:
2040 port->fifosize = 256;
2041 break;
2042 case PORT_SCIFA:
2043 port->fifosize = 64;
2044 break;
2045 case PORT_SCIF:
2046 port->fifosize = 16;
2047 break;
2048 default:
2049 port->fifosize = 1;
2050 break;
2051 }
2052
2053 if (p->regtype == SCIx_PROBE_REGTYPE) {
2054 ret = sci_probe_regmap(p);
2055 if (unlikely(ret))
2056 return ret;
2057 }
2058
2059 if (dev) {
2060 sci_port->iclk = clk_get(&dev->dev, "sci_ick");
2061 if (IS_ERR(sci_port->iclk)) {
2062 sci_port->iclk = clk_get(&dev->dev, "peripheral_clk");
2063 if (IS_ERR(sci_port->iclk)) {
2064 dev_err(&dev->dev, "can't get iclk\n");
2065 return PTR_ERR(sci_port->iclk);
2066 }
2067 }
2068
2069 /*
2070 * The function clock is optional, ignore it if we can't
2071 * find it.
2072 */
2073 sci_port->fclk = clk_get(&dev->dev, "sci_fck");
2074 if (IS_ERR(sci_port->fclk))
2075 sci_port->fclk = NULL;
2076
2077 port->dev = &dev->dev;
2078
2079 sci_init_gpios(sci_port);
2080
2081 pm_runtime_irq_safe(&dev->dev);
2082 pm_runtime_get_noresume(&dev->dev);
2083 pm_runtime_enable(&dev->dev);
2084 }
2085
2086 sci_port->break_timer.data = (unsigned long)sci_port;
2087 sci_port->break_timer.function = sci_break_timer;
2088 init_timer(&sci_port->break_timer);
2089
2090 /*
2091 * Establish some sensible defaults for the error detection.
2092 */
2093 if (!p->error_mask)
2094 p->error_mask = (p->type == PORT_SCI) ?
2095 SCI_DEFAULT_ERROR_MASK : SCIF_DEFAULT_ERROR_MASK;
2096
2097 /*
2098 * Establish sensible defaults for the overrun detection, unless
2099 * the part has explicitly disabled support for it.
2100 */
2101 if (p->overrun_bit != SCIx_NOT_SUPPORTED) {
2102 if (p->type == PORT_SCI)
2103 p->overrun_bit = 5;
2104 else if (p->scbrr_algo_id == SCBRR_ALGO_4)
2105 p->overrun_bit = 9;
2106 else
2107 p->overrun_bit = 0;
2108
2109 /*
2110 * Make the error mask inclusive of overrun detection, if
2111 * supported.
2112 */
2113 p->error_mask |= (1 << p->overrun_bit);
2114 }
2115
2116 port->mapbase = p->mapbase;
2117 port->type = p->type;
2118 port->flags = p->flags;
2119 port->regshift = p->regshift;
2120
2121 /*
2122 * The UART port needs an IRQ value, so we peg this to the RX IRQ
2123 * for the multi-IRQ ports, which is where we are primarily
2124 * concerned with the shutdown path synchronization.
2125 *
2126 * For the muxed case there's nothing more to do.
2127 */
2128 port->irq = p->irqs[SCIx_RXI_IRQ];
2129 port->irqflags = 0;
2130
2131 port->serial_in = sci_serial_in;
2132 port->serial_out = sci_serial_out;
2133
2134 if (p->dma_slave_tx > 0 && p->dma_slave_rx > 0)
2135 dev_dbg(port->dev, "DMA tx %d, rx %d\n",
2136 p->dma_slave_tx, p->dma_slave_rx);
2137
2138 return 0;
2139 }
2140
2141 #ifdef CONFIG_SERIAL_SH_SCI_CONSOLE
serial_console_putchar(struct uart_port * port,int ch)2142 static void serial_console_putchar(struct uart_port *port, int ch)
2143 {
2144 sci_poll_put_char(port, ch);
2145 }
2146
2147 /*
2148 * Print a string to the serial port trying not to disturb
2149 * any possible real use of the port...
2150 */
serial_console_write(struct console * co,const char * s,unsigned count)2151 static void serial_console_write(struct console *co, const char *s,
2152 unsigned count)
2153 {
2154 struct sci_port *sci_port = &sci_ports[co->index];
2155 struct uart_port *port = &sci_port->port;
2156 unsigned short bits;
2157
2158 sci_port_enable(sci_port);
2159
2160 uart_console_write(port, s, count, serial_console_putchar);
2161
2162 /* wait until fifo is empty and last bit has been transmitted */
2163 bits = SCxSR_TDxE(port) | SCxSR_TEND(port);
2164 while ((sci_in(port, SCxSR) & bits) != bits)
2165 cpu_relax();
2166
2167 sci_port_disable(sci_port);
2168 }
2169
serial_console_setup(struct console * co,char * options)2170 static int __devinit serial_console_setup(struct console *co, char *options)
2171 {
2172 struct sci_port *sci_port;
2173 struct uart_port *port;
2174 int baud = 115200;
2175 int bits = 8;
2176 int parity = 'n';
2177 int flow = 'n';
2178 int ret;
2179
2180 /*
2181 * Refuse to handle any bogus ports.
2182 */
2183 if (co->index < 0 || co->index >= SCI_NPORTS)
2184 return -ENODEV;
2185
2186 sci_port = &sci_ports[co->index];
2187 port = &sci_port->port;
2188
2189 /*
2190 * Refuse to handle uninitialized ports.
2191 */
2192 if (!port->ops)
2193 return -ENODEV;
2194
2195 ret = sci_remap_port(port);
2196 if (unlikely(ret != 0))
2197 return ret;
2198
2199 sci_port_enable(sci_port);
2200
2201 if (options)
2202 uart_parse_options(options, &baud, &parity, &bits, &flow);
2203
2204 sci_port_disable(sci_port);
2205
2206 return uart_set_options(port, co, baud, parity, bits, flow);
2207 }
2208
2209 static struct console serial_console = {
2210 .name = "ttySC",
2211 .device = uart_console_device,
2212 .write = serial_console_write,
2213 .setup = serial_console_setup,
2214 .flags = CON_PRINTBUFFER,
2215 .index = -1,
2216 .data = &sci_uart_driver,
2217 };
2218
2219 static struct console early_serial_console = {
2220 .name = "early_ttySC",
2221 .write = serial_console_write,
2222 .flags = CON_PRINTBUFFER,
2223 .index = -1,
2224 };
2225
2226 static char early_serial_buf[32];
2227
sci_probe_earlyprintk(struct platform_device * pdev)2228 static int __devinit sci_probe_earlyprintk(struct platform_device *pdev)
2229 {
2230 struct plat_sci_port *cfg = pdev->dev.platform_data;
2231
2232 if (early_serial_console.data)
2233 return -EEXIST;
2234
2235 early_serial_console.index = pdev->id;
2236
2237 sci_init_single(NULL, &sci_ports[pdev->id], pdev->id, cfg);
2238
2239 serial_console_setup(&early_serial_console, early_serial_buf);
2240
2241 if (!strstr(early_serial_buf, "keep"))
2242 early_serial_console.flags |= CON_BOOT;
2243
2244 register_console(&early_serial_console);
2245 return 0;
2246 }
2247
2248 #define uart_console(port) ((port)->cons->index == (port)->line)
2249
sci_runtime_suspend(struct device * dev)2250 static int sci_runtime_suspend(struct device *dev)
2251 {
2252 struct sci_port *sci_port = dev_get_drvdata(dev);
2253 struct uart_port *port = &sci_port->port;
2254
2255 if (uart_console(port)) {
2256 struct plat_sci_reg *reg;
2257
2258 sci_port->saved_smr = sci_in(port, SCSMR);
2259 sci_port->saved_brr = sci_in(port, SCBRR);
2260
2261 reg = sci_getreg(port, SCFCR);
2262 if (reg->size)
2263 sci_port->saved_fcr = sci_in(port, SCFCR);
2264 else
2265 sci_port->saved_fcr = 0;
2266 }
2267 return 0;
2268 }
2269
sci_runtime_resume(struct device * dev)2270 static int sci_runtime_resume(struct device *dev)
2271 {
2272 struct sci_port *sci_port = dev_get_drvdata(dev);
2273 struct uart_port *port = &sci_port->port;
2274
2275 if (uart_console(port)) {
2276 sci_reset(port);
2277 sci_out(port, SCSMR, sci_port->saved_smr);
2278 sci_out(port, SCBRR, sci_port->saved_brr);
2279
2280 if (sci_port->saved_fcr)
2281 sci_out(port, SCFCR, sci_port->saved_fcr);
2282
2283 sci_out(port, SCSCR, sci_port->cfg->scscr);
2284 }
2285 return 0;
2286 }
2287
2288 #define SCI_CONSOLE (&serial_console)
2289
2290 #else
sci_probe_earlyprintk(struct platform_device * pdev)2291 static inline int __devinit sci_probe_earlyprintk(struct platform_device *pdev)
2292 {
2293 return -EINVAL;
2294 }
2295
2296 #define SCI_CONSOLE NULL
2297 #define sci_runtime_suspend NULL
2298 #define sci_runtime_resume NULL
2299
2300 #endif /* CONFIG_SERIAL_SH_SCI_CONSOLE */
2301
2302 static char banner[] __initdata =
2303 KERN_INFO "SuperH SCI(F) driver initialized\n";
2304
2305 static struct uart_driver sci_uart_driver = {
2306 .owner = THIS_MODULE,
2307 .driver_name = "sci",
2308 .dev_name = "ttySC",
2309 .major = SCI_MAJOR,
2310 .minor = SCI_MINOR_START,
2311 .nr = SCI_NPORTS,
2312 .cons = SCI_CONSOLE,
2313 };
2314
sci_remove(struct platform_device * dev)2315 static int sci_remove(struct platform_device *dev)
2316 {
2317 struct sci_port *port = platform_get_drvdata(dev);
2318
2319 cpufreq_unregister_notifier(&port->freq_transition,
2320 CPUFREQ_TRANSITION_NOTIFIER);
2321
2322 sci_free_gpios(port);
2323
2324 uart_remove_one_port(&sci_uart_driver, &port->port);
2325
2326 clk_put(port->iclk);
2327 clk_put(port->fclk);
2328
2329 pm_runtime_disable(&dev->dev);
2330 return 0;
2331 }
2332
sci_probe_single(struct platform_device * dev,unsigned int index,struct plat_sci_port * p,struct sci_port * sciport)2333 static int __devinit sci_probe_single(struct platform_device *dev,
2334 unsigned int index,
2335 struct plat_sci_port *p,
2336 struct sci_port *sciport)
2337 {
2338 int ret;
2339
2340 /* Sanity check */
2341 if (unlikely(index >= SCI_NPORTS)) {
2342 dev_notice(&dev->dev, "Attempting to register port "
2343 "%d when only %d are available.\n",
2344 index+1, SCI_NPORTS);
2345 dev_notice(&dev->dev, "Consider bumping "
2346 "CONFIG_SERIAL_SH_SCI_NR_UARTS!\n");
2347 return 0;
2348 }
2349
2350 ret = sci_init_single(dev, sciport, index, p);
2351 if (ret)
2352 return ret;
2353
2354 return uart_add_one_port(&sci_uart_driver, &sciport->port);
2355 }
2356
sci_probe(struct platform_device * dev)2357 static int __devinit sci_probe(struct platform_device *dev)
2358 {
2359 struct plat_sci_port *p = dev->dev.platform_data;
2360 struct sci_port *sp = &sci_ports[dev->id];
2361 int ret;
2362
2363 /*
2364 * If we've come here via earlyprintk initialization, head off to
2365 * the special early probe. We don't have sufficient device state
2366 * to make it beyond this yet.
2367 */
2368 if (is_early_platform_device(dev))
2369 return sci_probe_earlyprintk(dev);
2370
2371 platform_set_drvdata(dev, sp);
2372
2373 ret = sci_probe_single(dev, dev->id, p, sp);
2374 if (ret)
2375 goto err_unreg;
2376
2377 sp->freq_transition.notifier_call = sci_notifier;
2378
2379 ret = cpufreq_register_notifier(&sp->freq_transition,
2380 CPUFREQ_TRANSITION_NOTIFIER);
2381 if (unlikely(ret < 0))
2382 goto err_unreg;
2383
2384 #ifdef CONFIG_SH_STANDARD_BIOS
2385 sh_bios_gdb_detach();
2386 #endif
2387
2388 return 0;
2389
2390 err_unreg:
2391 sci_remove(dev);
2392 return ret;
2393 }
2394
sci_suspend(struct device * dev)2395 static int sci_suspend(struct device *dev)
2396 {
2397 struct sci_port *sport = dev_get_drvdata(dev);
2398
2399 if (sport)
2400 uart_suspend_port(&sci_uart_driver, &sport->port);
2401
2402 return 0;
2403 }
2404
sci_resume(struct device * dev)2405 static int sci_resume(struct device *dev)
2406 {
2407 struct sci_port *sport = dev_get_drvdata(dev);
2408
2409 if (sport)
2410 uart_resume_port(&sci_uart_driver, &sport->port);
2411
2412 return 0;
2413 }
2414
2415 static const struct dev_pm_ops sci_dev_pm_ops = {
2416 .runtime_suspend = sci_runtime_suspend,
2417 .runtime_resume = sci_runtime_resume,
2418 .suspend = sci_suspend,
2419 .resume = sci_resume,
2420 };
2421
2422 static struct platform_driver sci_driver = {
2423 .probe = sci_probe,
2424 .remove = sci_remove,
2425 .driver = {
2426 .name = "sh-sci",
2427 .owner = THIS_MODULE,
2428 .pm = &sci_dev_pm_ops,
2429 },
2430 };
2431
sci_init(void)2432 static int __init sci_init(void)
2433 {
2434 int ret;
2435
2436 printk(banner);
2437
2438 ret = uart_register_driver(&sci_uart_driver);
2439 if (likely(ret == 0)) {
2440 ret = platform_driver_register(&sci_driver);
2441 if (unlikely(ret))
2442 uart_unregister_driver(&sci_uart_driver);
2443 }
2444
2445 return ret;
2446 }
2447
sci_exit(void)2448 static void __exit sci_exit(void)
2449 {
2450 platform_driver_unregister(&sci_driver);
2451 uart_unregister_driver(&sci_uart_driver);
2452 }
2453
2454 #ifdef CONFIG_SERIAL_SH_SCI_CONSOLE
2455 early_platform_init_buffer("earlyprintk", &sci_driver,
2456 early_serial_buf, ARRAY_SIZE(early_serial_buf));
2457 #endif
2458 module_init(sci_init);
2459 module_exit(sci_exit);
2460
2461 MODULE_LICENSE("GPL");
2462 MODULE_ALIAS("platform:sh-sci");
2463 MODULE_AUTHOR("Paul Mundt");
2464 MODULE_DESCRIPTION("SuperH SCI(F) serial driver");
2465