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Linux 3.12.39
[linux/fpc-iii.git] / drivers / tty / serial / bcm63xx_uart.c
blob88b07adedaef90af13afac3349e7067f84e1ba2e
1 /*
2 * This file is subject to the terms and conditions of the GNU General Public
3 * License. See the file "COPYING" in the main directory of this archive
4 * for more details.
5 *
6 * Derived from many drivers using generic_serial interface.
7 *
8 * Copyright (C) 2008 Maxime Bizon <mbizon@freebox.fr>
9 *
10 * Serial driver for BCM63xx integrated UART.
11 *
12 * Hardware flow control was _not_ tested since I only have RX/TX on
13 * my board.
14 */
15
16 #if defined(CONFIG_SERIAL_BCM63XX_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
17 #define SUPPORT_SYSRQ
18 #endif
19
20 #include <linux/kernel.h>
21 #include <linux/platform_device.h>
22 #include <linux/init.h>
23 #include <linux/delay.h>
24 #include <linux/module.h>
25 #include <linux/console.h>
26 #include <linux/clk.h>
27 #include <linux/tty.h>
28 #include <linux/tty_flip.h>
29 #include <linux/sysrq.h>
30 #include <linux/serial.h>
31 #include <linux/serial_core.h>
32
33 #include <bcm63xx_irq.h>
34 #include <bcm63xx_regs.h>
35 #include <bcm63xx_io.h>
36
37 #define BCM63XX_NR_UARTS 2
38
39 static struct uart_port ports[BCM63XX_NR_UARTS];
40
41 /*
42 * rx interrupt mask / stat
43 *
44 * mask:
45 * - rx fifo full
46 * - rx fifo above threshold
47 * - rx fifo not empty for too long
48 */
49 #define UART_RX_INT_MASK (UART_IR_MASK(UART_IR_RXOVER) | \
50 UART_IR_MASK(UART_IR_RXTHRESH) | \
51 UART_IR_MASK(UART_IR_RXTIMEOUT))
52
53 #define UART_RX_INT_STAT (UART_IR_STAT(UART_IR_RXOVER) | \
54 UART_IR_STAT(UART_IR_RXTHRESH) | \
55 UART_IR_STAT(UART_IR_RXTIMEOUT))
56
57 /*
58 * tx interrupt mask / stat
59 *
60 * mask:
61 * - tx fifo empty
62 * - tx fifo below threshold
63 */
64 #define UART_TX_INT_MASK (UART_IR_MASK(UART_IR_TXEMPTY) | \
65 UART_IR_MASK(UART_IR_TXTRESH))
66
67 #define UART_TX_INT_STAT (UART_IR_STAT(UART_IR_TXEMPTY) | \
68 UART_IR_STAT(UART_IR_TXTRESH))
69
70 /*
71 * external input interrupt
72 *
73 * mask: any edge on CTS, DCD
74 */
75 #define UART_EXTINP_INT_MASK (UART_EXTINP_IRMASK(UART_EXTINP_IR_CTS) | \
76 UART_EXTINP_IRMASK(UART_EXTINP_IR_DCD))
77
78 /*
79 * handy uart register accessor
80 */
81 static inline unsigned int bcm_uart_readl(struct uart_port *port,
82 unsigned int offset)
83 {
84 return bcm_readl(port->membase + offset);
85 }
86
87 static inline void bcm_uart_writel(struct uart_port *port,
88 unsigned int value, unsigned int offset)
89 {
90 bcm_writel(value, port->membase + offset);
91 }
92
93 /*
94 * serial core request to check if uart tx fifo is empty
95 */
96 static unsigned int bcm_uart_tx_empty(struct uart_port *port)
97 {
98 unsigned int val;
99
100 val = bcm_uart_readl(port, UART_IR_REG);
101 return (val & UART_IR_STAT(UART_IR_TXEMPTY)) ? 1 : 0;
102 }
103
104 /*
105 * serial core request to set RTS and DTR pin state and loopback mode
106 */
107 static void bcm_uart_set_mctrl(struct uart_port *port, unsigned int mctrl)
108 {
109 unsigned int val;
110
111 val = bcm_uart_readl(port, UART_MCTL_REG);
112 val &= ~(UART_MCTL_DTR_MASK | UART_MCTL_RTS_MASK);
113 /* invert of written value is reflected on the pin */
114 if (!(mctrl & TIOCM_DTR))
115 val |= UART_MCTL_DTR_MASK;
116 if (!(mctrl & TIOCM_RTS))
117 val |= UART_MCTL_RTS_MASK;
118 bcm_uart_writel(port, val, UART_MCTL_REG);
119
120 val = bcm_uart_readl(port, UART_CTL_REG);
121 if (mctrl & TIOCM_LOOP)
122 val |= UART_CTL_LOOPBACK_MASK;
123 else
124 val &= ~UART_CTL_LOOPBACK_MASK;
125 bcm_uart_writel(port, val, UART_CTL_REG);
126 }
127
128 /*
129 * serial core request to return RI, CTS, DCD and DSR pin state
130 */
131 static unsigned int bcm_uart_get_mctrl(struct uart_port *port)
132 {
133 unsigned int val, mctrl;
134
135 mctrl = 0;
136 val = bcm_uart_readl(port, UART_EXTINP_REG);
137 if (val & UART_EXTINP_RI_MASK)
138 mctrl |= TIOCM_RI;
139 if (val & UART_EXTINP_CTS_MASK)
140 mctrl |= TIOCM_CTS;
141 if (val & UART_EXTINP_DCD_MASK)
142 mctrl |= TIOCM_CD;
143 if (val & UART_EXTINP_DSR_MASK)
144 mctrl |= TIOCM_DSR;
145 return mctrl;
146 }
147
148 /*
149 * serial core request to disable tx ASAP (used for flow control)
150 */
151 static void bcm_uart_stop_tx(struct uart_port *port)
152 {
153 unsigned int val;
154
155 val = bcm_uart_readl(port, UART_CTL_REG);
156 val &= ~(UART_CTL_TXEN_MASK);
157 bcm_uart_writel(port, val, UART_CTL_REG);
158
159 val = bcm_uart_readl(port, UART_IR_REG);
160 val &= ~UART_TX_INT_MASK;
161 bcm_uart_writel(port, val, UART_IR_REG);
162 }
163
164 /*
165 * serial core request to (re)enable tx
166 */
167 static void bcm_uart_start_tx(struct uart_port *port)
168 {
169 unsigned int val;
170
171 val = bcm_uart_readl(port, UART_IR_REG);
172 val |= UART_TX_INT_MASK;
173 bcm_uart_writel(port, val, UART_IR_REG);
174
175 val = bcm_uart_readl(port, UART_CTL_REG);
176 val |= UART_CTL_TXEN_MASK;
177 bcm_uart_writel(port, val, UART_CTL_REG);
178 }
179
180 /*
181 * serial core request to stop rx, called before port shutdown
182 */
183 static void bcm_uart_stop_rx(struct uart_port *port)
184 {
185 unsigned int val;
186
187 val = bcm_uart_readl(port, UART_IR_REG);
188 val &= ~UART_RX_INT_MASK;
189 bcm_uart_writel(port, val, UART_IR_REG);
190 }
191
192 /*
193 * serial core request to enable modem status interrupt reporting
194 */
195 static void bcm_uart_enable_ms(struct uart_port *port)
196 {
197 unsigned int val;
198
199 val = bcm_uart_readl(port, UART_IR_REG);
200 val |= UART_IR_MASK(UART_IR_EXTIP);
201 bcm_uart_writel(port, val, UART_IR_REG);
202 }
203
204 /*
205 * serial core request to start/stop emitting break char
206 */
207 static void bcm_uart_break_ctl(struct uart_port *port, int ctl)
208 {
209 unsigned long flags;
210 unsigned int val;
211
212 spin_lock_irqsave(&port->lock, flags);
213
214 val = bcm_uart_readl(port, UART_CTL_REG);
215 if (ctl)
216 val |= UART_CTL_XMITBRK_MASK;
217 else
218 val &= ~UART_CTL_XMITBRK_MASK;
219 bcm_uart_writel(port, val, UART_CTL_REG);
220
221 spin_unlock_irqrestore(&port->lock, flags);
222 }
223
224 /*
225 * return port type in string format
226 */
227 static const char *bcm_uart_type(struct uart_port *port)
228 {
229 return (port->type == PORT_BCM63XX) ? "bcm63xx_uart" : NULL;
230 }
231
232 /*
233 * read all chars in rx fifo and send them to core
234 */
235 static void bcm_uart_do_rx(struct uart_port *port)
236 {
237 struct tty_port *tty_port = &port->state->port;
238 unsigned int max_count;
239
240 /* limit number of char read in interrupt, should not be
241 * higher than fifo size anyway since we're much faster than
242 * serial port */
243 max_count = 32;
244 do {
245 unsigned int iestat, c, cstat;
246 char flag;
247
248 /* get overrun/fifo empty information from ier
249 * register */
250 iestat = bcm_uart_readl(port, UART_IR_REG);
251
252 if (unlikely(iestat & UART_IR_STAT(UART_IR_RXOVER))) {
253 unsigned int val;
254
255 /* fifo reset is required to clear
256 * interrupt */
257 val = bcm_uart_readl(port, UART_CTL_REG);
258 val |= UART_CTL_RSTRXFIFO_MASK;
259 bcm_uart_writel(port, val, UART_CTL_REG);
260
261 port->icount.overrun++;
262 tty_insert_flip_char(tty_port, 0, TTY_OVERRUN);
263 }
264
265 if (!(iestat & UART_IR_STAT(UART_IR_RXNOTEMPTY)))
266 break;
267
268 cstat = c = bcm_uart_readl(port, UART_FIFO_REG);
269 port->icount.rx++;
270 flag = TTY_NORMAL;
271 c &= 0xff;
272
273 if (unlikely((cstat & UART_FIFO_ANYERR_MASK))) {
274 /* do stats first */
275 if (cstat & UART_FIFO_BRKDET_MASK) {
276 port->icount.brk++;
277 if (uart_handle_break(port))
278 continue;
279 }
280
281 if (cstat & UART_FIFO_PARERR_MASK)
282 port->icount.parity++;
283 if (cstat & UART_FIFO_FRAMEERR_MASK)
284 port->icount.frame++;
285
286 /* update flag wrt read_status_mask */
287 cstat &= port->read_status_mask;
288 if (cstat & UART_FIFO_BRKDET_MASK)
289 flag = TTY_BREAK;
290 if (cstat & UART_FIFO_FRAMEERR_MASK)
291 flag = TTY_FRAME;
292 if (cstat & UART_FIFO_PARERR_MASK)
293 flag = TTY_PARITY;
294 }
295
296 if (uart_handle_sysrq_char(port, c))
297 continue;
298
299
300 if ((cstat & port->ignore_status_mask) == 0)
301 tty_insert_flip_char(tty_port, c, flag);
302
303 } while (--max_count);
304
305 spin_unlock(&port->lock);
306 tty_flip_buffer_push(tty_port);
307 spin_lock(&port->lock);
308 }
309
310 /*
311 * fill tx fifo with chars to send, stop when fifo is about to be full
312 * or when all chars have been sent.
313 */
314 static void bcm_uart_do_tx(struct uart_port *port)
315 {
316 struct circ_buf *xmit;
317 unsigned int val, max_count;
318
319 if (port->x_char) {
320 bcm_uart_writel(port, port->x_char, UART_FIFO_REG);
321 port->icount.tx++;
322 port->x_char = 0;
323 return;
324 }
325
326 if (uart_tx_stopped(port)) {
327 bcm_uart_stop_tx(port);
328 return;
329 }
330
331 xmit = &port->state->xmit;
332 if (uart_circ_empty(xmit))
333 goto txq_empty;
334
335 val = bcm_uart_readl(port, UART_MCTL_REG);
336 val = (val & UART_MCTL_TXFIFOFILL_MASK) >> UART_MCTL_TXFIFOFILL_SHIFT;
337 max_count = port->fifosize - val;
338
339 while (max_count--) {
340 unsigned int c;
341
342 c = xmit->buf[xmit->tail];
343 bcm_uart_writel(port, c, UART_FIFO_REG);
344 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
345 port->icount.tx++;
346 if (uart_circ_empty(xmit))
347 break;
348 }
349
350 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
351 uart_write_wakeup(port);
352
353 if (uart_circ_empty(xmit))
354 goto txq_empty;
355 return;
356
357 txq_empty:
358 /* nothing to send, disable transmit interrupt */
359 val = bcm_uart_readl(port, UART_IR_REG);
360 val &= ~UART_TX_INT_MASK;
361 bcm_uart_writel(port, val, UART_IR_REG);
362 return;
363 }
364
365 /*
366 * process uart interrupt
367 */
368 static irqreturn_t bcm_uart_interrupt(int irq, void *dev_id)
369 {
370 struct uart_port *port;
371 unsigned int irqstat;
372
373 port = dev_id;
374 spin_lock(&port->lock);
375
376 irqstat = bcm_uart_readl(port, UART_IR_REG);
377 if (irqstat & UART_RX_INT_STAT)
378 bcm_uart_do_rx(port);
379
380 if (irqstat & UART_TX_INT_STAT)
381 bcm_uart_do_tx(port);
382
383 if (irqstat & UART_IR_MASK(UART_IR_EXTIP)) {
384 unsigned int estat;
385
386 estat = bcm_uart_readl(port, UART_EXTINP_REG);
387 if (estat & UART_EXTINP_IRSTAT(UART_EXTINP_IR_CTS))
388 uart_handle_cts_change(port,
389 estat & UART_EXTINP_CTS_MASK);
390 if (estat & UART_EXTINP_IRSTAT(UART_EXTINP_IR_DCD))
391 uart_handle_dcd_change(port,
392 estat & UART_EXTINP_DCD_MASK);
393 }
394
395 spin_unlock(&port->lock);
396 return IRQ_HANDLED;
397 }
398
399 /*
400 * enable rx & tx operation on uart
401 */
402 static void bcm_uart_enable(struct uart_port *port)
403 {
404 unsigned int val;
405
406 val = bcm_uart_readl(port, UART_CTL_REG);
407 val |= (UART_CTL_BRGEN_MASK | UART_CTL_TXEN_MASK | UART_CTL_RXEN_MASK);
408 bcm_uart_writel(port, val, UART_CTL_REG);
409 }
410
411 /*
412 * disable rx & tx operation on uart
413 */
414 static void bcm_uart_disable(struct uart_port *port)
415 {
416 unsigned int val;
417
418 val = bcm_uart_readl(port, UART_CTL_REG);
419 val &= ~(UART_CTL_BRGEN_MASK | UART_CTL_TXEN_MASK |
420 UART_CTL_RXEN_MASK);
421 bcm_uart_writel(port, val, UART_CTL_REG);
422 }
423
424 /*
425 * clear all unread data in rx fifo and unsent data in tx fifo
426 */
427 static void bcm_uart_flush(struct uart_port *port)
428 {
429 unsigned int val;
430
431 /* empty rx and tx fifo */
432 val = bcm_uart_readl(port, UART_CTL_REG);
433 val |= UART_CTL_RSTRXFIFO_MASK | UART_CTL_RSTTXFIFO_MASK;
434 bcm_uart_writel(port, val, UART_CTL_REG);
435
436 /* read any pending char to make sure all irq status are
437 * cleared */
438 (void)bcm_uart_readl(port, UART_FIFO_REG);
439 }
440
441 /*
442 * serial core request to initialize uart and start rx operation
443 */
444 static int bcm_uart_startup(struct uart_port *port)
445 {
446 unsigned int val;
447 int ret;
448
449 /* mask all irq and flush port */
450 bcm_uart_disable(port);
451 bcm_uart_writel(port, 0, UART_IR_REG);
452 bcm_uart_flush(port);
453
454 /* clear any pending external input interrupt */
455 (void)bcm_uart_readl(port, UART_EXTINP_REG);
456
457 /* set rx/tx fifo thresh to fifo half size */
458 val = bcm_uart_readl(port, UART_MCTL_REG);
459 val &= ~(UART_MCTL_RXFIFOTHRESH_MASK | UART_MCTL_TXFIFOTHRESH_MASK);
460 val |= (port->fifosize / 2) << UART_MCTL_RXFIFOTHRESH_SHIFT;
461 val |= (port->fifosize / 2) << UART_MCTL_TXFIFOTHRESH_SHIFT;
462 bcm_uart_writel(port, val, UART_MCTL_REG);
463
464 /* set rx fifo timeout to 1 char time */
465 val = bcm_uart_readl(port, UART_CTL_REG);
466 val &= ~UART_CTL_RXTMOUTCNT_MASK;
467 val |= 1 << UART_CTL_RXTMOUTCNT_SHIFT;
468 bcm_uart_writel(port, val, UART_CTL_REG);
469
470 /* report any edge on dcd and cts */
471 val = UART_EXTINP_INT_MASK;
472 val |= UART_EXTINP_DCD_NOSENSE_MASK;
473 val |= UART_EXTINP_CTS_NOSENSE_MASK;
474 bcm_uart_writel(port, val, UART_EXTINP_REG);
475
476 /* register irq and enable rx interrupts */
477 ret = request_irq(port->irq, bcm_uart_interrupt, 0,
478 bcm_uart_type(port), port);
479 if (ret)
480 return ret;
481 bcm_uart_writel(port, UART_RX_INT_MASK, UART_IR_REG);
482 bcm_uart_enable(port);
483 return 0;
484 }
485
486 /*
487 * serial core request to flush & disable uart
488 */
489 static void bcm_uart_shutdown(struct uart_port *port)
490 {
491 unsigned long flags;
492
493 spin_lock_irqsave(&port->lock, flags);
494 bcm_uart_writel(port, 0, UART_IR_REG);
495 spin_unlock_irqrestore(&port->lock, flags);
496
497 bcm_uart_disable(port);
498 bcm_uart_flush(port);
499 free_irq(port->irq, port);
500 }
501
502 /*
503 * serial core request to change current uart setting
504 */
505 static void bcm_uart_set_termios(struct uart_port *port,
506 struct ktermios *new,
507 struct ktermios *old)
508 {
509 unsigned int ctl, baud, quot, ier;
510 unsigned long flags;
511
512 spin_lock_irqsave(&port->lock, flags);
513
514 /* disable uart while changing speed */
515 bcm_uart_disable(port);
516 bcm_uart_flush(port);
517
518 /* update Control register */
519 ctl = bcm_uart_readl(port, UART_CTL_REG);
520 ctl &= ~UART_CTL_BITSPERSYM_MASK;
521
522 switch (new->c_cflag & CSIZE) {
523 case CS5:
524 ctl |= (0 << UART_CTL_BITSPERSYM_SHIFT);
525 break;
526 case CS6:
527 ctl |= (1 << UART_CTL_BITSPERSYM_SHIFT);
528 break;
529 case CS7:
530 ctl |= (2 << UART_CTL_BITSPERSYM_SHIFT);
531 break;
532 default:
533 ctl |= (3 << UART_CTL_BITSPERSYM_SHIFT);
534 break;
535 }
536
537 ctl &= ~UART_CTL_STOPBITS_MASK;
538 if (new->c_cflag & CSTOPB)
539 ctl |= UART_CTL_STOPBITS_2;
540 else
541 ctl |= UART_CTL_STOPBITS_1;
542
543 ctl &= ~(UART_CTL_RXPAREN_MASK | UART_CTL_TXPAREN_MASK);
544 if (new->c_cflag & PARENB)
545 ctl |= (UART_CTL_RXPAREN_MASK | UART_CTL_TXPAREN_MASK);
546 ctl &= ~(UART_CTL_RXPAREVEN_MASK | UART_CTL_TXPAREVEN_MASK);
547 if (new->c_cflag & PARODD)
548 ctl |= (UART_CTL_RXPAREVEN_MASK | UART_CTL_TXPAREVEN_MASK);
549 bcm_uart_writel(port, ctl, UART_CTL_REG);
550
551 /* update Baudword register */
552 baud = uart_get_baud_rate(port, new, old, 0, port->uartclk / 16);
553 quot = uart_get_divisor(port, baud) - 1;
554 bcm_uart_writel(port, quot, UART_BAUD_REG);
555
556 /* update Interrupt register */
557 ier = bcm_uart_readl(port, UART_IR_REG);
558
559 ier &= ~UART_IR_MASK(UART_IR_EXTIP);
560 if (UART_ENABLE_MS(port, new->c_cflag))
561 ier |= UART_IR_MASK(UART_IR_EXTIP);
562
563 bcm_uart_writel(port, ier, UART_IR_REG);
564
565 /* update read/ignore mask */
566 port->read_status_mask = UART_FIFO_VALID_MASK;
567 if (new->c_iflag & INPCK) {
568 port->read_status_mask |= UART_FIFO_FRAMEERR_MASK;
569 port->read_status_mask |= UART_FIFO_PARERR_MASK;
570 }
571 if (new->c_iflag & (IGNBRK | BRKINT))
572 port->read_status_mask |= UART_FIFO_BRKDET_MASK;
573
574 port->ignore_status_mask = 0;
575 if (new->c_iflag & IGNPAR)
576 port->ignore_status_mask |= UART_FIFO_PARERR_MASK;
577 if (new->c_iflag & IGNBRK)
578 port->ignore_status_mask |= UART_FIFO_BRKDET_MASK;
579 if (!(new->c_cflag & CREAD))
580 port->ignore_status_mask |= UART_FIFO_VALID_MASK;
581
582 uart_update_timeout(port, new->c_cflag, baud);
583 bcm_uart_enable(port);
584 spin_unlock_irqrestore(&port->lock, flags);
585 }
586
587 /*
588 * serial core request to claim uart iomem
589 */
590 static int bcm_uart_request_port(struct uart_port *port)
591 {
592 unsigned int size;
593
594 size = RSET_UART_SIZE;
595 if (!request_mem_region(port->mapbase, size, "bcm63xx")) {
596 dev_err(port->dev, "Memory region busy\n");
597 return -EBUSY;
598 }
599
600 port->membase = ioremap(port->mapbase, size);
601 if (!port->membase) {
602 dev_err(port->dev, "Unable to map registers\n");
603 release_mem_region(port->mapbase, size);
604 return -EBUSY;
605 }
606 return 0;
607 }
608
609 /*
610 * serial core request to release uart iomem
611 */
612 static void bcm_uart_release_port(struct uart_port *port)
613 {
614 release_mem_region(port->mapbase, RSET_UART_SIZE);
615 iounmap(port->membase);
616 }
617
618 /*
619 * serial core request to do any port required autoconfiguration
620 */
621 static void bcm_uart_config_port(struct uart_port *port, int flags)
622 {
623 if (flags & UART_CONFIG_TYPE) {
624 if (bcm_uart_request_port(port))
625 return;
626 port->type = PORT_BCM63XX;
627 }
628 }
629
630 /*
631 * serial core request to check that port information in serinfo are
632 * suitable
633 */
634 static int bcm_uart_verify_port(struct uart_port *port,
635 struct serial_struct *serinfo)
636 {
637 if (port->type != PORT_BCM63XX)
638 return -EINVAL;
639 if (port->irq != serinfo->irq)
640 return -EINVAL;
641 if (port->iotype != serinfo->io_type)
642 return -EINVAL;
643 if (port->mapbase != (unsigned long)serinfo->iomem_base)
644 return -EINVAL;
645 return 0;
646 }
647
648 /* serial core callbacks */
649 static struct uart_ops bcm_uart_ops = {
650 .tx_empty = bcm_uart_tx_empty,
651 .get_mctrl = bcm_uart_get_mctrl,
652 .set_mctrl = bcm_uart_set_mctrl,
653 .start_tx = bcm_uart_start_tx,
654 .stop_tx = bcm_uart_stop_tx,
655 .stop_rx = bcm_uart_stop_rx,
656 .enable_ms = bcm_uart_enable_ms,
657 .break_ctl = bcm_uart_break_ctl,
658 .startup = bcm_uart_startup,
659 .shutdown = bcm_uart_shutdown,
660 .set_termios = bcm_uart_set_termios,
661 .type = bcm_uart_type,
662 .release_port = bcm_uart_release_port,
663 .request_port = bcm_uart_request_port,
664 .config_port = bcm_uart_config_port,
665 .verify_port = bcm_uart_verify_port,
666 };
667
668
669
670 #ifdef CONFIG_SERIAL_BCM63XX_CONSOLE
671 static inline void wait_for_xmitr(struct uart_port *port)
672 {
673 unsigned int tmout;
674
675 /* Wait up to 10ms for the character(s) to be sent. */
676 tmout = 10000;
677 while (--tmout) {
678 unsigned int val;
679
680 val = bcm_uart_readl(port, UART_IR_REG);
681 if (val & UART_IR_STAT(UART_IR_TXEMPTY))
682 break;
683 udelay(1);
684 }
685
686 /* Wait up to 1s for flow control if necessary */
687 if (port->flags & UPF_CONS_FLOW) {
688 tmout = 1000000;
689 while (--tmout) {
690 unsigned int val;
691
692 val = bcm_uart_readl(port, UART_EXTINP_REG);
693 if (val & UART_EXTINP_CTS_MASK)
694 break;
695 udelay(1);
696 }
697 }
698 }
699
700 /*
701 * output given char
702 */
703 static void bcm_console_putchar(struct uart_port *port, int ch)
704 {
705 wait_for_xmitr(port);
706 bcm_uart_writel(port, ch, UART_FIFO_REG);
707 }
708
709 /*
710 * console core request to output given string
711 */
712 static void bcm_console_write(struct console *co, const char *s,
713 unsigned int count)
714 {
715 struct uart_port *port;
716 unsigned long flags;
717 int locked;
718
719 port = &ports[co->index];
720
721 local_irq_save(flags);
722 if (port->sysrq) {
723 /* bcm_uart_interrupt() already took the lock */
724 locked = 0;
725 } else if (oops_in_progress) {
726 locked = spin_trylock(&port->lock);
727 } else {
728 spin_lock(&port->lock);
729 locked = 1;
730 }
731
732 /* call helper to deal with \r\n */
733 uart_console_write(port, s, count, bcm_console_putchar);
734
735 /* and wait for char to be transmitted */
736 wait_for_xmitr(port);
737
738 if (locked)
739 spin_unlock(&port->lock);
740 local_irq_restore(flags);
741 }
742
743 /*
744 * console core request to setup given console, find matching uart
745 * port and setup it.
746 */
747 static int bcm_console_setup(struct console *co, char *options)
748 {
749 struct uart_port *port;
750 int baud = 9600;
751 int bits = 8;
752 int parity = 'n';
753 int flow = 'n';
754
755 if (co->index < 0 || co->index >= BCM63XX_NR_UARTS)
756 return -EINVAL;
757 port = &ports[co->index];
758 if (!port->membase)
759 return -ENODEV;
760 if (options)
761 uart_parse_options(options, &baud, &parity, &bits, &flow);
762
763 return uart_set_options(port, co, baud, parity, bits, flow);
764 }
765
766 static struct uart_driver bcm_uart_driver;
767
768 static struct console bcm63xx_console = {
769 .name = "ttyS",
770 .write = bcm_console_write,
771 .device = uart_console_device,
772 .setup = bcm_console_setup,
773 .flags = CON_PRINTBUFFER,
774 .index = -1,
775 .data = &bcm_uart_driver,
776 };
777
778 static int __init bcm63xx_console_init(void)
779 {
780 register_console(&bcm63xx_console);
781 return 0;
782 }
783
784 console_initcall(bcm63xx_console_init);
785
786 #define BCM63XX_CONSOLE (&bcm63xx_console)
787 #else
788 #define BCM63XX_CONSOLE NULL
789 #endif /* CONFIG_SERIAL_BCM63XX_CONSOLE */
790
791 static struct uart_driver bcm_uart_driver = {
792 .owner = THIS_MODULE,
793 .driver_name = "bcm63xx_uart",
794 .dev_name = "ttyS",
795 .major = TTY_MAJOR,
796 .minor = 64,
797 .nr = BCM63XX_NR_UARTS,
798 .cons = BCM63XX_CONSOLE,
799 };
800
801 /*
802 * platform driver probe/remove callback
803 */
804 static int bcm_uart_probe(struct platform_device *pdev)
805 {
806 struct resource *res_mem, *res_irq;
807 struct uart_port *port;
808 struct clk *clk;
809 int ret;
810
811 if (pdev->id < 0 || pdev->id >= BCM63XX_NR_UARTS)
812 return -EINVAL;
813
814 if (ports[pdev->id].membase)
815 return -EBUSY;
816
817 res_mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
818 if (!res_mem)
819 return -ENODEV;
820
821 res_irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
822 if (!res_irq)
823 return -ENODEV;
824
825 clk = clk_get(&pdev->dev, "periph");
826 if (IS_ERR(clk))
827 return -ENODEV;
828
829 port = &ports[pdev->id];
830 memset(port, 0, sizeof(*port));
831 port->iotype = UPIO_MEM;
832 port->mapbase = res_mem->start;
833 port->irq = res_irq->start;
834 port->ops = &bcm_uart_ops;
835 port->flags = UPF_BOOT_AUTOCONF;
836 port->dev = &pdev->dev;
837 port->fifosize = 16;
838 port->uartclk = clk_get_rate(clk) / 2;
839 port->line = pdev->id;
840 clk_put(clk);
841
842 ret = uart_add_one_port(&bcm_uart_driver, port);
843 if (ret) {
844 ports[pdev->id].membase = 0;
845 return ret;
846 }
847 platform_set_drvdata(pdev, port);
848 return 0;
849 }
850
851 static int bcm_uart_remove(struct platform_device *pdev)
852 {
853 struct uart_port *port;
854
855 port = platform_get_drvdata(pdev);
856 uart_remove_one_port(&bcm_uart_driver, port);
857 /* mark port as free */
858 ports[pdev->id].membase = 0;
859 return 0;
860 }
861
862 /*
863 * platform driver stuff
864 */
865 static struct platform_driver bcm_uart_platform_driver = {
866 .probe = bcm_uart_probe,
867 .remove = bcm_uart_remove,
868 .driver = {
869 .owner = THIS_MODULE,
870 .name = "bcm63xx_uart",
871 },
872 };
873
874 static int __init bcm_uart_init(void)
875 {
876 int ret;
877
878 ret = uart_register_driver(&bcm_uart_driver);
879 if (ret)
880 return ret;
881
882 ret = platform_driver_register(&bcm_uart_platform_driver);
883 if (ret)
884 uart_unregister_driver(&bcm_uart_driver);
885
886 return ret;
887 }
888
889 static void __exit bcm_uart_exit(void)
890 {
891 platform_driver_unregister(&bcm_uart_platform_driver);
892 uart_unregister_driver(&bcm_uart_driver);
893 }
894
895 module_init(bcm_uart_init);
896 module_exit(bcm_uart_exit);
897
898 MODULE_AUTHOR("Maxime Bizon <mbizon@freebox.fr>");
899 MODULE_DESCRIPTION("Broadcom 63<xx integrated uart driver");
900 MODULE_LICENSE("GPL");
Linux with added FPC-III support