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1 /* 1
2 * SC268xx.c: Serial driver for Philiphs SC268
3 *
4 * Copyright (C) 2006,2007 Thomas Bogendörfer
5 */
6
7 #include <linux/module.h>
8 #include <linux/kernel.h>
9 #include <linux/errno.h>
10 #include <linux/tty.h>
11 #include <linux/tty_flip.h>
12 #include <linux/major.h>
13 #include <linux/circ_buf.h>
14 #include <linux/serial.h>
15 #include <linux/sysrq.h>
16 #include <linux/console.h>
17 #include <linux/spinlock.h>
18 #include <linux/slab.h>
19 #include <linux/delay.h>
20 #include <linux/init.h>
21 #include <linux/platform_device.h>
22 #include <linux/irq.h>
23
24 #if defined(CONFIG_MAGIC_SYSRQ)
25 #define SUPPORT_SYSRQ
26 #endif
27
28 #include <linux/serial_core.h>
29
30 #define SC26XX_MAJOR 204
31 #define SC26XX_MINOR_START 205
32 #define SC26XX_NR 2
33
34 struct uart_sc26xx_port {
35 struct uart_port port[2];
36 u8 dsr_mask[2];
37 u8 cts_mask[2];
38 u8 dcd_mask[2];
39 u8 ri_mask[2];
40 u8 dtr_mask[2];
41 u8 rts_mask[2];
42 u8 imr;
43 };
44
45 /* register common to both ports */
46 #define RD_ISR 0x14
47 #define RD_IPR 0x34
48
49 #define WR_ACR 0x10
50 #define WR_IMR 0x14
51 #define WR_OPCR 0x34
52 #define WR_OPR_SET 0x38
53 #define WR_OPR_CLR 0x3C
54
55 /* access common register */
56 #define READ_SC(p, r) readb((p)->membas
57 #define WRITE_SC(p, r, v) writeb((v), (p)->
58
59 /* register per port */
60 #define RD_PORT_MRx 0x00
61 #define RD_PORT_SR 0x04
62 #define RD_PORT_RHR 0x0c
63
64 #define WR_PORT_MRx 0x00
65 #define WR_PORT_CSR 0x04
66 #define WR_PORT_CR 0x08
67 #define WR_PORT_THR 0x0c
68
69 /* SR bits */
70 #define SR_BREAK (1 << 7)
71 #define SR_FRAME (1 << 6)
72 #define SR_PARITY (1 << 5)
73 #define SR_OVERRUN (1 << 4)
74 #define SR_TXRDY (1 << 2)
75 #define SR_RXRDY (1 << 0)
76
77 #define CR_RES_MR (1 << 4)
78 #define CR_RES_RX (2 << 4)
79 #define CR_RES_TX (3 << 4)
80 #define CR_STRT_BRK (6 << 4)
81 #define CR_STOP_BRK (7 << 4)
82 #define CR_DIS_TX (1 << 3)
83 #define CR_ENA_TX (1 << 2)
84 #define CR_DIS_RX (1 << 1)
85 #define CR_ENA_RX (1 << 0)
86
87 /* ISR bits */
88 #define ISR_RXRDYB (1 << 5)
89 #define ISR_TXRDYB (1 << 4)
90 #define ISR_RXRDYA (1 << 1)
91 #define ISR_TXRDYA (1 << 0)
92
93 /* IMR bits */
94 #define IMR_RXRDY (1 << 1)
95 #define IMR_TXRDY (1 << 0)
96
97 /* access port register */
98 static inline u8 read_sc_port(struct uart_port
99 {
100 return readb(p->membase + p->line * 0x
101 }
102
103 static inline void write_sc_port(struct uart_p
104 {
105 writeb(val, p->membase + p->line * 0x2
106 }
107
108 #define READ_SC_PORT(p, r) read_sc_port(p,
109 #define WRITE_SC_PORT(p, r, v) write_sc_port(p
110
111 static void sc26xx_enable_irq(struct uart_port
112 {
113 struct uart_sc26xx_port *up;
114 int line = port->line;
115
116 port -= line;
117 up = container_of(port, struct uart_sc
118
119 up->imr |= mask << (line * 4);
120 WRITE_SC(port, IMR, up->imr);
121 }
122
123 static void sc26xx_disable_irq(struct uart_por
124 {
125 struct uart_sc26xx_port *up;
126 int line = port->line;
127
128 port -= line;
129 up = container_of(port, struct uart_sc
130
131 up->imr &= ~(mask << (line * 4));
132 WRITE_SC(port, IMR, up->imr);
133 }
134
135 static struct tty_struct *receive_chars(struct
136 {
137 struct tty_struct *tty = NULL;
138 int limit = 10000;
139 unsigned char ch;
140 char flag;
141 u8 status;
142
143 if (port->info != NULL) /* Uno
144 tty = port->info->tty;
145
146 while (limit-- > 0) {
147 status = READ_SC_PORT(port, SR
148 if (!(status & SR_RXRDY))
149 break;
150 ch = READ_SC_PORT(port, RHR);
151
152 flag = TTY_NORMAL;
153 port->icount.rx++;
154
155 if (unlikely(status & (SR_BREA
156 SR_PARI
157 if (status & SR_BREAK)
158 status &= ~(SR
159 port->icount.b
160 if (uart_handl
161 contin
162 } else if (status & SR
163 port->icount.p
164 else if (status & SR_F
165 port->icount.f
166 if (status & SR_OVERRU
167 port->icount.o
168
169 status &= port->read_s
170 if (status & SR_BREAK)
171 flag = TTY_BRE
172 else if (status & SR_P
173 flag = TTY_PAR
174 else if (status & SR_F
175 flag = TTY_FRA
176 }
177
178 if (uart_handle_sysrq_char(por
179 continue;
180
181 if (status & port->ignore_stat
182 continue;
183
184 tty_insert_flip_char(tty, ch,
185 }
186 return tty;
187 }
188
189 static void transmit_chars(struct uart_port *p
190 {
191 struct circ_buf *xmit;
192
193 if (!port->info)
194 return;
195
196 xmit = &port->info->xmit;
197 if (uart_circ_empty(xmit) || uart_tx_s
198 sc26xx_disable_irq(port, IMR_T
199 return;
200 }
201 while (!uart_circ_empty(xmit)) {
202 if (!(READ_SC_PORT(port, SR) &
203 break;
204
205 WRITE_SC_PORT(port, THR, xmit-
206 xmit->tail = (xmit->tail + 1)
207 port->icount.tx++;
208 }
209 if (uart_circ_chars_pending(xmit) < WA
210 uart_write_wakeup(port);
211 }
212
213 static irqreturn_t sc26xx_interrupt(int irq, v
214 {
215 struct uart_sc26xx_port *up = dev_id;
216 struct tty_struct *tty;
217 unsigned long flags;
218 u8 isr;
219
220 spin_lock_irqsave(&up->port[0].lock, f
221
222 tty = NULL;
223 isr = READ_SC(&up->port[0], ISR);
224 if (isr & ISR_TXRDYA)
225 transmit_chars(&up->port[0]);
226 if (isr & ISR_RXRDYA)
227 tty = receive_chars(&up->port[0]);
228
229 spin_unlock(&up->port[0].lock);
230
231 if (tty)
232 tty_flip_buffer_push(tty);
233
234 spin_lock(&up->port[1].lock);
235
236 tty = NULL;
237 if (isr & ISR_TXRDYB)
238 transmit_chars(&up->port[1]);
239 if (isr & ISR_RXRDYB)
240 tty = receive_chars(&up->port[1]);
241
242 spin_unlock_irqrestore(&up->port[1].lo
243
244 if (tty)
245 tty_flip_buffer_push(tty);
246
247 return IRQ_HANDLED;
248 }
249
250 /* port->lock is not held. */
251 static unsigned int sc26xx_tx_empty(struct uar
252 {
253 return (READ_SC_PORT(port, SR) & SR_TX
254 }
255
256 /* port->lock held by caller. */
257 static void sc26xx_set_mctrl(struct uart_port
258 {
259 struct uart_sc26xx_port *up;
260 int line = port->line;
261
262 port -= line;
263 up = container_of(port, struct uart_sc
264
265 if (up->dtr_mask[line]) {
266 if (mctrl & TIOCM_DTR)
267 WRITE_SC(port, OPR_SET
268 else
269 WRITE_SC(port, OPR_CLR
270 }
271 if (up->rts_mask[line]) {
272 if (mctrl & TIOCM_RTS)
273 WRITE_SC(port, OPR_SET
274 else
275 WRITE_SC(port, OPR_CLR
276 }
277 }
278
279 /* port->lock is held by caller and interrupts
280 static unsigned int sc26xx_get_mctrl(struct ua
281 {
282 struct uart_sc26xx_port *up;
283 int line = port->line;
284 unsigned int mctrl = TIOCM_DSR | TIOCM
285 u8 ipr;
286
287 port -= line;
288 up = container_of(port, struct uart_sc
289 ipr = READ_SC(port, IPR) ^ 0xff;
290
291 if (up->dsr_mask[line]) {
292 mctrl &= ~TIOCM_DSR;
293 mctrl |= ipr & up->dsr_mask[li
294 }
295 if (up->cts_mask[line]) {
296 mctrl &= ~TIOCM_CTS;
297 mctrl |= ipr & up->cts_mask[li
298 }
299 if (up->dcd_mask[line]) {
300 mctrl &= ~TIOCM_CAR;
301 mctrl |= ipr & up->dcd_mask[li
302 }
303 if (up->ri_mask[line]) {
304 mctrl &= ~TIOCM_RNG;
305 mctrl |= ipr & up->ri_mask[lin
306 }
307 return mctrl;
308 }
309
310 /* port->lock held by caller. */
311 static void sc26xx_stop_tx(struct uart_port *p
312 {
313 return;
314 }
315
316 /* port->lock held by caller. */
317 static void sc26xx_start_tx(struct uart_port *
318 {
319 struct circ_buf *xmit = &port->info->x
320
321 while (!uart_circ_empty(xmit)) {
322 if (!(READ_SC_PORT(port, SR) &
323 sc26xx_enable_irq(port
324 break;
325 }
326 WRITE_SC_PORT(port, THR, xmit-
327 xmit->tail = (xmit->tail + 1)
328 port->icount.tx++;
329 }
330 }
331
332 /* port->lock held by caller. */
333 static void sc26xx_stop_rx(struct uart_port *p
334 {
335 }
336
337 /* port->lock held by caller. */
338 static void sc26xx_enable_ms(struct uart_port
339 {
340 }
341
342 /* port->lock is not held. */
343 static void sc26xx_break_ctl(struct uart_port
344 {
345 if (break_state == -1)
346 WRITE_SC_PORT(port, CR, CR_STR
347 else
348 WRITE_SC_PORT(port, CR, CR_STO
349 }
350
351 /* port->lock is not held. */
352 static int sc26xx_startup(struct uart_port *po
353 {
354 sc26xx_disable_irq(port, IMR_TXRDY | I
355 WRITE_SC(port, OPCR, 0);
356
357 /* reset tx and rx */
358 WRITE_SC_PORT(port, CR, CR_RES_RX);
359 WRITE_SC_PORT(port, CR, CR_RES_TX);
360
361 /* start rx/tx */
362 WRITE_SC_PORT(port, CR, CR_ENA_TX | CR
363
364 /* enable irqs */
365 sc26xx_enable_irq(port, IMR_RXRDY);
366 return 0;
367 }
368
369 /* port->lock is not held. */
370 static void sc26xx_shutdown(struct uart_port *
371 {
372 /* disable interrupst */
373 sc26xx_disable_irq(port, IMR_TXRDY | I
374
375 /* stop tx/rx */
376 WRITE_SC_PORT(port, CR, CR_DIS_TX | CR
377 }
378
379 /* port->lock is not held. */
380 static void sc26xx_set_termios(struct uart_por
381 struct ktermios
382 {
383 unsigned int baud = uart_get_baud_rate
384 unsigned int quot = uart_get_divisor(p
385 unsigned int iflag, cflag;
386 unsigned long flags;
387 u8 mr1, mr2, csr;
388
389 spin_lock_irqsave(&port->lock, flags);
390
391 while ((READ_SC_PORT(port, SR) & ((1 <
392 udelay(2);
393
394 WRITE_SC_PORT(port, CR, CR_DIS_TX | CR
395
396 iflag = termios->c_iflag;
397 cflag = termios->c_cflag;
398
399 port->read_status_mask = SR_OVERRUN;
400 if (iflag & INPCK)
401 port->read_status_mask |= SR_P
402 if (iflag & (BRKINT | PARMRK))
403 port->read_status_mask |= SR_B
404
405 port->ignore_status_mask = 0;
406 if (iflag & IGNBRK)
407 port->ignore_status_mask |= SR
408 if ((cflag & CREAD) == 0)
409 port->ignore_status_mask |= SR
410 SR
411
412 switch (cflag & CSIZE) {
413 case CS5:
414 mr1 = 0x00;
415 break;
416 case CS6:
417 mr1 = 0x01;
418 break;
419 case CS7:
420 mr1 = 0x02;
421 break;
422 default:
423 case CS8:
424 mr1 = 0x03;
425 break;
426 }
427 mr2 = 0x07;
428 if (cflag & CSTOPB)
429 mr2 = 0x0f;
430 if (cflag & PARENB) {
431 if (cflag & PARODD)
432 mr1 |= (1 << 2);
433 } else
434 mr1 |= (2 << 3);
435
436 switch (baud) {
437 case 50:
438 csr = 0x00;
439 break;
440 case 110:
441 csr = 0x11;
442 break;
443 case 134:
444 csr = 0x22;
445 break;
446 case 200:
447 csr = 0x33;
448 break;
449 case 300:
450 csr = 0x44;
451 break;
452 case 600:
453 csr = 0x55;
454 break;
455 case 1200:
456 csr = 0x66;
457 break;
458 case 2400:
459 csr = 0x88;
460 break;
461 case 4800:
462 csr = 0x99;
463 break;
464 default:
465 case 9600:
466 csr = 0xbb;
467 break;
468 case 19200:
469 csr = 0xcc;
470 break;
471 }
472
473 WRITE_SC_PORT(port, CR, CR_RES_MR);
474 WRITE_SC_PORT(port, MRx, mr1);
475 WRITE_SC_PORT(port, MRx, mr2);
476
477 WRITE_SC(port, ACR, 0x80);
478 WRITE_SC_PORT(port, CSR, csr);
479
480 /* reset tx and rx */
481 WRITE_SC_PORT(port, CR, CR_RES_RX);
482 WRITE_SC_PORT(port, CR, CR_RES_TX);
483
484 WRITE_SC_PORT(port, CR, CR_ENA_TX | CR
485 while ((READ_SC_PORT(port, SR) & ((1 <
486 udelay(2);
487
488 /* XXX */
489 uart_update_timeout(port, cflag,
490 (port->uartclk / (
491
492 spin_unlock_irqrestore(&port->lock, fl
493 }
494
495 static const char *sc26xx_type(struct uart_por
496 {
497 return "SC26XX";
498 }
499
500 static void sc26xx_release_port(struct uart_po
501 {
502 }
503
504 static int sc26xx_request_port(struct uart_por
505 {
506 return 0;
507 }
508
509 static void sc26xx_config_port(struct uart_por
510 {
511 }
512
513 static int sc26xx_verify_port(struct uart_port
514 {
515 return -EINVAL;
516 }
517
518 static struct uart_ops sc26xx_ops = {
519 .tx_empty = sc26xx_tx_empty,
520 .set_mctrl = sc26xx_set_mctrl,
521 .get_mctrl = sc26xx_get_mctrl,
522 .stop_tx = sc26xx_stop_tx,
523 .start_tx = sc26xx_start_tx,
524 .stop_rx = sc26xx_stop_rx,
525 .enable_ms = sc26xx_enable_ms,
526 .break_ctl = sc26xx_break_ctl,
527 .startup = sc26xx_startup,
528 .shutdown = sc26xx_shutdown,
529 .set_termios = sc26xx_set_termios,
530 .type = sc26xx_type,
531 .release_port = sc26xx_release_port,
532 .request_port = sc26xx_request_port,
533 .config_port = sc26xx_config_port,
534 .verify_port = sc26xx_verify_port,
535 };
536
537 static struct uart_port *sc26xx_port;
538
539 #ifdef CONFIG_SERIAL_SC26XX_CONSOLE
540 static void sc26xx_console_putchar(struct uart
541 {
542 unsigned long flags;
543 int limit = 1000000;
544
545 spin_lock_irqsave(&port->lock, flags);
546
547 while (limit-- > 0) {
548 if (READ_SC_PORT(port, SR) & S
549 WRITE_SC_PORT(port, TH
550 break;
551 }
552 udelay(2);
553 }
554
555 spin_unlock_irqrestore(&port->lock, fl
556 }
557
558 static void sc26xx_console_write(struct consol
559 {
560 struct uart_port *port = sc26xx_port;
561 int i;
562
563 for (i = 0; i < n; i++) {
564 if (*s == '\n')
565 sc26xx_console_putchar
566 sc26xx_console_putchar(port, *
567 }
568 }
569
570 static int __init sc26xx_console_setup(struct
571 {
572 struct uart_port *port = sc26xx_port;
573 int baud = 9600;
574 int bits = 8;
575 int parity = 'n';
576 int flow = 'n';
577
578 if (port->type != PORT_SC26XX)
579 return -1;
580
581 printk(KERN_INFO "Console: ttySC%d (SC
582 if (options)
583 uart_parse_options(options, &b
584
585 return uart_set_options(port, con, bau
586 }
587
588 static struct uart_driver sc26xx_reg;
589 static struct console sc26xx_console = {
590 .name = "ttySC",
591 .write = sc26xx_console_write,
592 .device = uart_console_device,
593 .setup = sc26xx_console_setup,
594 .flags = CON_PRINTBUFFER,
595 .index = -1,
596 .data = &sc26xx_reg,
597 };
598 #define SC26XX_CONSOLE &sc26xx_console
599 #else
600 #define SC26XX_CONSOLE NULL
601 #endif
602
603 static struct uart_driver sc26xx_reg = {
604 .owner = THIS_MODULE,
605 .driver_name = "SC26xx",
606 .dev_name = "ttySC",
607 .major = SC26XX_MAJOR
608 .minor = SC26XX_MINOR
609 .nr = SC26XX_NR,
610 .cons = SC26XX_CONSO
611 };
612
613 static u8 sc26xx_flags2mask(unsigned int flags
614 {
615 unsigned int bit = (flags >> bitpos) &
616
617 return bit ? (1 << (bit - 1)) : 0;
618 }
619
620 static void __devinit sc26xx_init_masks(struct
621 int li
622 {
623 up->dtr_mask[line] = sc26xx_flags2mask
624 up->rts_mask[line] = sc26xx_flags2mask
625 up->dsr_mask[line] = sc26xx_flags2mask
626 up->cts_mask[line] = sc26xx_flags2mask
627 up->dcd_mask[line] = sc26xx_flags2mask
628 up->ri_mask[line] = sc26xx_flags2mask
629 }
630
631 static int __devinit sc26xx_probe(struct platf
632 {
633 struct resource *res;
634 struct uart_sc26xx_port *up;
635 unsigned int *sc26xx_data = dev->dev.p
636 int err;
637
638 res = platform_get_resource(dev, IORES
639 if (!res)
640 return -ENODEV;
641
642 up = kzalloc(sizeof *up, GFP_KERNEL);
643 if (unlikely(!up))
644 return -ENOMEM;
645
646 up->port[0].line = 0;
647 up->port[0].ops = &sc26xx_ops;
648 up->port[0].type = PORT_SC26XX;
649 up->port[0].uartclk = (29491200 / 16);
650
651 up->port[0].mapbase = res->start;
652 up->port[0].membase = ioremap_nocache(
653 up->port[0].iotype = UPIO_MEM;
654 up->port[0].irq = platform_get_irq(dev
655
656 up->port[0].dev = &dev->dev;
657
658 sc26xx_init_masks(up, 0, sc26xx_data[0
659
660 sc26xx_port = &up->port[0];
661
662 up->port[1].line = 1;
663 up->port[1].ops = &sc26xx_ops;
664 up->port[1].type = PORT_SC26XX;
665 up->port[1].uartclk = (29491200 / 16);
666
667 up->port[1].mapbase = up->port[0].mapb
668 up->port[1].membase = up->port[0].memb
669 up->port[1].iotype = UPIO_MEM;
670 up->port[1].irq = up->port[0].irq;
671
672 up->port[1].dev = &dev->dev;
673
674 sc26xx_init_masks(up, 1, sc26xx_data[1
675
676 err = uart_register_driver(&sc26xx_reg
677 if (err)
678 goto out_free_port;
679
680 sc26xx_reg.tty_driver->name_base = sc2
681
682 err = uart_add_one_port(&sc26xx_reg, &
683 if (err)
684 goto out_unregister_driver;
685
686 err = uart_add_one_port(&sc26xx_reg, &
687 if (err)
688 goto out_remove_port0;
689
690 err = request_irq(up->port[0].irq, sc2
691 if (err)
692 goto out_remove_ports;
693
694 dev_set_drvdata(&dev->dev, up);
695 return 0;
696
697 out_remove_ports:
698 uart_remove_one_port(&sc26xx_reg, &up-
699 out_remove_port0:
700 uart_remove_one_port(&sc26xx_reg, &up-
701
702 out_unregister_driver:
703 uart_unregister_driver(&sc26xx_reg);
704
705 out_free_port:
706 kfree(up);
707 sc26xx_port = NULL;
708 return err;
709 }
710
711
712 static int __exit sc26xx_driver_remove(struct
713 {
714 struct uart_sc26xx_port *up = dev_get_
715
716 free_irq(up->port[0].irq, up);
717
718 uart_remove_one_port(&sc26xx_reg, &up-
719 uart_remove_one_port(&sc26xx_reg, &up-
720
721 uart_unregister_driver(&sc26xx_reg);
722
723 kfree(up);
724 sc26xx_port = NULL;
725
726 dev_set_drvdata(&dev->dev, NULL);
727 return 0;
728 }
729
730 static struct platform_driver sc26xx_driver =
731 .probe = sc26xx_probe,
732 .remove = __devexit_p(sc26xx_driver_re
733 .driver = {
734 .name = "SC26xx",
735 .owner = THIS_MODULE,
736 },
737 };
738
739 static int __init sc26xx_init(void)
740 {
741 return platform_driver_register(&sc26x
742 }
743
744 static void __exit sc26xx_exit(void)
745 {
746 platform_driver_unregister(&sc26xx_dri
747 }
748
749 module_init(sc26xx_init);
750 module_exit(sc26xx_exit);
751
752
753 MODULE_AUTHOR("Thomas Bogendörfer");
754 MODULE_DESCRIPTION("SC681/SC2692 serial driver
755 MODULE_VERSION("1.0");
756 MODULE_LICENSE("GPL");
757 MODULE_ALIAS("platform:SC26xx");
758
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