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Linux-2.6.12-rc2
[thirdparty/linux.git] / drivers / serial / amba-pl011.c
1 /*
2 * linux/drivers/char/amba.c
3 *
4 * Driver for AMBA serial ports
5 *
6 * Based on drivers/char/serial.c, by Linus Torvalds, Theodore Ts'o.
7 *
8 * Copyright 1999 ARM Limited
9 * Copyright (C) 2000 Deep Blue Solutions Ltd.
10 *
11 * This program is free software; you can redistribute it and/or modify
12 * it under the terms of the GNU General Public License as published by
13 * the Free Software Foundation; either version 2 of the License, or
14 * (at your option) any later version.
15 *
16 * This program is distributed in the hope that it will be useful,
17 * but WITHOUT ANY WARRANTY; without even the implied warranty of
18 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
19 * GNU General Public License for more details.
20 *
21 * You should have received a copy of the GNU General Public License
22 * along with this program; if not, write to the Free Software
23 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
24 *
25 * $Id: amba.c,v 1.41 2002/07/28 10:03:27 rmk Exp $
26 *
27 * This is a generic driver for ARM AMBA-type serial ports. They
28 * have a lot of 16550-like features, but are not register compatible.
29 * Note that although they do have CTS, DCD and DSR inputs, they do
30 * not have an RI input, nor do they have DTR or RTS outputs. If
31 * required, these have to be supplied via some other means (eg, GPIO)
32 * and hooked into this driver.
33 */
34 #include <linux/config.h>
35
36 #if defined(CONFIG_SERIAL_AMBA_PL011_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
37 #define SUPPORT_SYSRQ
38 #endif
39
40 #include <linux/module.h>
41 #include <linux/ioport.h>
42 #include <linux/init.h>
43 #include <linux/console.h>
44 #include <linux/sysrq.h>
45 #include <linux/device.h>
46 #include <linux/tty.h>
47 #include <linux/tty_flip.h>
48 #include <linux/serial_core.h>
49 #include <linux/serial.h>
50
51 #include <asm/io.h>
52 #include <asm/irq.h>
53 #include <asm/hardware/amba.h>
54 #include <asm/hardware/clock.h>
55 #include <asm/hardware/amba_serial.h>
56
57 #define UART_NR 14
58
59 #define SERIAL_AMBA_MAJOR 204
60 #define SERIAL_AMBA_MINOR 64
61 #define SERIAL_AMBA_NR UART_NR
62
63 #define AMBA_ISR_PASS_LIMIT 256
64
65 #define UART_DUMMY_RSR_RX 256
66
67 /*
68 * We wrap our port structure around the generic uart_port.
69 */
70 struct uart_amba_port {
71 struct uart_port port;
72 struct clk *clk;
73 unsigned int im; /* interrupt mask */
74 unsigned int old_status;
75 };
76
77 static void pl011_stop_tx(struct uart_port *port, unsigned int tty_stop)
78 {
79 struct uart_amba_port *uap = (struct uart_amba_port *)port;
80
81 uap->im &= ~UART011_TXIM;
82 writew(uap->im, uap->port.membase + UART011_IMSC);
83 }
84
85 static void pl011_start_tx(struct uart_port *port, unsigned int tty_start)
86 {
87 struct uart_amba_port *uap = (struct uart_amba_port *)port;
88
89 uap->im |= UART011_TXIM;
90 writew(uap->im, uap->port.membase + UART011_IMSC);
91 }
92
93 static void pl011_stop_rx(struct uart_port *port)
94 {
95 struct uart_amba_port *uap = (struct uart_amba_port *)port;
96
97 uap->im &= ~(UART011_RXIM|UART011_RTIM|UART011_FEIM|
98 UART011_PEIM|UART011_BEIM|UART011_OEIM);
99 writew(uap->im, uap->port.membase + UART011_IMSC);
100 }
101
102 static void pl011_enable_ms(struct uart_port *port)
103 {
104 struct uart_amba_port *uap = (struct uart_amba_port *)port;
105
106 uap->im |= UART011_RIMIM|UART011_CTSMIM|UART011_DCDMIM|UART011_DSRMIM;
107 writew(uap->im, uap->port.membase + UART011_IMSC);
108 }
109
110 static void
111 #ifdef SUPPORT_SYSRQ
112 pl011_rx_chars(struct uart_amba_port *uap, struct pt_regs *regs)
113 #else
114 pl011_rx_chars(struct uart_amba_port *uap)
115 #endif
116 {
117 struct tty_struct *tty = uap->port.info->tty;
118 unsigned int status, ch, flag, rsr, max_count = 256;
119
120 status = readw(uap->port.membase + UART01x_FR);
121 while ((status & UART01x_FR_RXFE) == 0 && max_count--) {
122 if (tty->flip.count >= TTY_FLIPBUF_SIZE) {
123 if (tty->low_latency)
124 tty_flip_buffer_push(tty);
125 /*
126 * If this failed then we will throw away the
127 * bytes but must do so to clear interrupts
128 */
129 }
130
131 ch = readw(uap->port.membase + UART01x_DR);
132 flag = TTY_NORMAL;
133 uap->port.icount.rx++;
134
135 /*
136 * Note that the error handling code is
137 * out of the main execution path
138 */
139 rsr = readw(uap->port.membase + UART01x_RSR) | UART_DUMMY_RSR_RX;
140 if (rsr & UART01x_RSR_ANY) {
141 if (rsr & UART01x_RSR_BE) {
142 rsr &= ~(UART01x_RSR_FE | UART01x_RSR_PE);
143 uap->port.icount.brk++;
144 if (uart_handle_break(&uap->port))
145 goto ignore_char;
146 } else if (rsr & UART01x_RSR_PE)
147 uap->port.icount.parity++;
148 else if (rsr & UART01x_RSR_FE)
149 uap->port.icount.frame++;
150 if (rsr & UART01x_RSR_OE)
151 uap->port.icount.overrun++;
152
153 rsr &= uap->port.read_status_mask;
154
155 if (rsr & UART01x_RSR_BE)
156 flag = TTY_BREAK;
157 else if (rsr & UART01x_RSR_PE)
158 flag = TTY_PARITY;
159 else if (rsr & UART01x_RSR_FE)
160 flag = TTY_FRAME;
161 }
162
163 if (uart_handle_sysrq_char(&uap->port, ch, regs))
164 goto ignore_char;
165
166 if ((rsr & uap->port.ignore_status_mask) == 0) {
167 tty_insert_flip_char(tty, ch, flag);
168 }
169 if ((rsr & UART01x_RSR_OE) &&
170 tty->flip.count < TTY_FLIPBUF_SIZE) {
171 /*
172 * Overrun is special, since it's reported
173 * immediately, and doesn't affect the current
174 * character
175 */
176 tty_insert_flip_char(tty, 0, TTY_OVERRUN);
177 }
178 ignore_char:
179 status = readw(uap->port.membase + UART01x_FR);
180 }
181 tty_flip_buffer_push(tty);
182 return;
183 }
184
185 static void pl011_tx_chars(struct uart_amba_port *uap)
186 {
187 struct circ_buf *xmit = &uap->port.info->xmit;
188 int count;
189
190 if (uap->port.x_char) {
191 writew(uap->port.x_char, uap->port.membase + UART01x_DR);
192 uap->port.icount.tx++;
193 uap->port.x_char = 0;
194 return;
195 }
196 if (uart_circ_empty(xmit) || uart_tx_stopped(&uap->port)) {
197 pl011_stop_tx(&uap->port, 0);
198 return;
199 }
200
201 count = uap->port.fifosize >> 1;
202 do {
203 writew(xmit->buf[xmit->tail], uap->port.membase + UART01x_DR);
204 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
205 uap->port.icount.tx++;
206 if (uart_circ_empty(xmit))
207 break;
208 } while (--count > 0);
209
210 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
211 uart_write_wakeup(&uap->port);
212
213 if (uart_circ_empty(xmit))
214 pl011_stop_tx(&uap->port, 0);
215 }
216
217 static void pl011_modem_status(struct uart_amba_port *uap)
218 {
219 unsigned int status, delta;
220
221 status = readw(uap->port.membase + UART01x_FR) & UART01x_FR_MODEM_ANY;
222
223 delta = status ^ uap->old_status;
224 uap->old_status = status;
225
226 if (!delta)
227 return;
228
229 if (delta & UART01x_FR_DCD)
230 uart_handle_dcd_change(&uap->port, status & UART01x_FR_DCD);
231
232 if (delta & UART01x_FR_DSR)
233 uap->port.icount.dsr++;
234
235 if (delta & UART01x_FR_CTS)
236 uart_handle_cts_change(&uap->port, status & UART01x_FR_CTS);
237
238 wake_up_interruptible(&uap->port.info->delta_msr_wait);
239 }
240
241 static irqreturn_t pl011_int(int irq, void *dev_id, struct pt_regs *regs)
242 {
243 struct uart_amba_port *uap = dev_id;
244 unsigned int status, pass_counter = AMBA_ISR_PASS_LIMIT;
245 int handled = 0;
246
247 spin_lock(&uap->port.lock);
248
249 status = readw(uap->port.membase + UART011_MIS);
250 if (status) {
251 do {
252 writew(status & ~(UART011_TXIS|UART011_RTIS|
253 UART011_RXIS),
254 uap->port.membase + UART011_ICR);
255
256 if (status & (UART011_RTIS|UART011_RXIS))
257 #ifdef SUPPORT_SYSRQ
258 pl011_rx_chars(uap, regs);
259 #else
260 pl011_rx_chars(uap);
261 #endif
262 if (status & (UART011_DSRMIS|UART011_DCDMIS|
263 UART011_CTSMIS|UART011_RIMIS))
264 pl011_modem_status(uap);
265 if (status & UART011_TXIS)
266 pl011_tx_chars(uap);
267
268 if (pass_counter-- == 0)
269 break;
270
271 status = readw(uap->port.membase + UART011_MIS);
272 } while (status != 0);
273 handled = 1;
274 }
275
276 spin_unlock(&uap->port.lock);
277
278 return IRQ_RETVAL(handled);
279 }
280
281 static unsigned int pl01x_tx_empty(struct uart_port *port)
282 {
283 struct uart_amba_port *uap = (struct uart_amba_port *)port;
284 unsigned int status = readw(uap->port.membase + UART01x_FR);
285 return status & (UART01x_FR_BUSY|UART01x_FR_TXFF) ? 0 : TIOCSER_TEMT;
286 }
287
288 static unsigned int pl01x_get_mctrl(struct uart_port *port)
289 {
290 struct uart_amba_port *uap = (struct uart_amba_port *)port;
291 unsigned int result = 0;
292 unsigned int status = readw(uap->port.membase + UART01x_FR);
293
294 #define BIT(uartbit, tiocmbit) \
295 if (status & uartbit) \
296 result |= tiocmbit
297
298 BIT(UART01x_FR_DCD, TIOCM_CAR);
299 BIT(UART01x_FR_DSR, TIOCM_DSR);
300 BIT(UART01x_FR_CTS, TIOCM_CTS);
301 BIT(UART011_FR_RI, TIOCM_RNG);
302 #undef BIT
303 return result;
304 }
305
306 static void pl011_set_mctrl(struct uart_port *port, unsigned int mctrl)
307 {
308 struct uart_amba_port *uap = (struct uart_amba_port *)port;
309 unsigned int cr;
310
311 cr = readw(uap->port.membase + UART011_CR);
312
313 #define BIT(tiocmbit, uartbit) \
314 if (mctrl & tiocmbit) \
315 cr |= uartbit; \
316 else \
317 cr &= ~uartbit
318
319 BIT(TIOCM_RTS, UART011_CR_RTS);
320 BIT(TIOCM_DTR, UART011_CR_DTR);
321 BIT(TIOCM_OUT1, UART011_CR_OUT1);
322 BIT(TIOCM_OUT2, UART011_CR_OUT2);
323 BIT(TIOCM_LOOP, UART011_CR_LBE);
324 #undef BIT
325
326 writew(cr, uap->port.membase + UART011_CR);
327 }
328
329 static void pl011_break_ctl(struct uart_port *port, int break_state)
330 {
331 struct uart_amba_port *uap = (struct uart_amba_port *)port;
332 unsigned long flags;
333 unsigned int lcr_h;
334
335 spin_lock_irqsave(&uap->port.lock, flags);
336 lcr_h = readw(uap->port.membase + UART011_LCRH);
337 if (break_state == -1)
338 lcr_h |= UART01x_LCRH_BRK;
339 else
340 lcr_h &= ~UART01x_LCRH_BRK;
341 writew(lcr_h, uap->port.membase + UART011_LCRH);
342 spin_unlock_irqrestore(&uap->port.lock, flags);
343 }
344
345 static int pl011_startup(struct uart_port *port)
346 {
347 struct uart_amba_port *uap = (struct uart_amba_port *)port;
348 unsigned int cr;
349 int retval;
350
351 /*
352 * Try to enable the clock producer.
353 */
354 retval = clk_enable(uap->clk);
355 if (retval)
356 goto out;
357
358 uap->port.uartclk = clk_get_rate(uap->clk);
359
360 /*
361 * Allocate the IRQ
362 */
363 retval = request_irq(uap->port.irq, pl011_int, 0, "uart-pl011", uap);
364 if (retval)
365 goto clk_dis;
366
367 writew(UART011_IFLS_RX4_8|UART011_IFLS_TX4_8,
368 uap->port.membase + UART011_IFLS);
369
370 /*
371 * Provoke TX FIFO interrupt into asserting.
372 */
373 cr = UART01x_CR_UARTEN | UART011_CR_TXE | UART011_CR_LBE;
374 writew(cr, uap->port.membase + UART011_CR);
375 writew(0, uap->port.membase + UART011_FBRD);
376 writew(1, uap->port.membase + UART011_IBRD);
377 writew(0, uap->port.membase + UART011_LCRH);
378 writew(0, uap->port.membase + UART01x_DR);
379 while (readw(uap->port.membase + UART01x_FR) & UART01x_FR_BUSY)
380 barrier();
381
382 cr = UART01x_CR_UARTEN | UART011_CR_RXE | UART011_CR_TXE;
383 writew(cr, uap->port.membase + UART011_CR);
384
385 /*
386 * initialise the old status of the modem signals
387 */
388 uap->old_status = readw(uap->port.membase + UART01x_FR) & UART01x_FR_MODEM_ANY;
389
390 /*
391 * Finally, enable interrupts
392 */
393 spin_lock_irq(&uap->port.lock);
394 uap->im = UART011_RXIM | UART011_RTIM;
395 writew(uap->im, uap->port.membase + UART011_IMSC);
396 spin_unlock_irq(&uap->port.lock);
397
398 return 0;
399
400 clk_dis:
401 clk_disable(uap->clk);
402 out:
403 return retval;
404 }
405
406 static void pl011_shutdown(struct uart_port *port)
407 {
408 struct uart_amba_port *uap = (struct uart_amba_port *)port;
409 unsigned long val;
410
411 /*
412 * disable all interrupts
413 */
414 spin_lock_irq(&uap->port.lock);
415 uap->im = 0;
416 writew(uap->im, uap->port.membase + UART011_IMSC);
417 writew(0xffff, uap->port.membase + UART011_ICR);
418 spin_unlock_irq(&uap->port.lock);
419
420 /*
421 * Free the interrupt
422 */
423 free_irq(uap->port.irq, uap);
424
425 /*
426 * disable the port
427 */
428 writew(UART01x_CR_UARTEN | UART011_CR_TXE, uap->port.membase + UART011_CR);
429
430 /*
431 * disable break condition and fifos
432 */
433 val = readw(uap->port.membase + UART011_LCRH);
434 val &= ~(UART01x_LCRH_BRK | UART01x_LCRH_FEN);
435 writew(val, uap->port.membase + UART011_LCRH);
436
437 /*
438 * Shut down the clock producer
439 */
440 clk_disable(uap->clk);
441 }
442
443 static void
444 pl011_set_termios(struct uart_port *port, struct termios *termios,
445 struct termios *old)
446 {
447 unsigned int lcr_h, old_cr;
448 unsigned long flags;
449 unsigned int baud, quot;
450
451 /*
452 * Ask the core to calculate the divisor for us.
453 */
454 baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk/16);
455 quot = port->uartclk * 4 / baud;
456
457 switch (termios->c_cflag & CSIZE) {
458 case CS5:
459 lcr_h = UART01x_LCRH_WLEN_5;
460 break;
461 case CS6:
462 lcr_h = UART01x_LCRH_WLEN_6;
463 break;
464 case CS7:
465 lcr_h = UART01x_LCRH_WLEN_7;
466 break;
467 default: // CS8
468 lcr_h = UART01x_LCRH_WLEN_8;
469 break;
470 }
471 if (termios->c_cflag & CSTOPB)
472 lcr_h |= UART01x_LCRH_STP2;
473 if (termios->c_cflag & PARENB) {
474 lcr_h |= UART01x_LCRH_PEN;
475 if (!(termios->c_cflag & PARODD))
476 lcr_h |= UART01x_LCRH_EPS;
477 }
478 if (port->fifosize > 1)
479 lcr_h |= UART01x_LCRH_FEN;
480
481 spin_lock_irqsave(&port->lock, flags);
482
483 /*
484 * Update the per-port timeout.
485 */
486 uart_update_timeout(port, termios->c_cflag, baud);
487
488 port->read_status_mask = UART01x_RSR_OE;
489 if (termios->c_iflag & INPCK)
490 port->read_status_mask |= UART01x_RSR_FE | UART01x_RSR_PE;
491 if (termios->c_iflag & (BRKINT | PARMRK))
492 port->read_status_mask |= UART01x_RSR_BE;
493
494 /*
495 * Characters to ignore
496 */
497 port->ignore_status_mask = 0;
498 if (termios->c_iflag & IGNPAR)
499 port->ignore_status_mask |= UART01x_RSR_FE | UART01x_RSR_PE;
500 if (termios->c_iflag & IGNBRK) {
501 port->ignore_status_mask |= UART01x_RSR_BE;
502 /*
503 * If we're ignoring parity and break indicators,
504 * ignore overruns too (for real raw support).
505 */
506 if (termios->c_iflag & IGNPAR)
507 port->ignore_status_mask |= UART01x_RSR_OE;
508 }
509
510 /*
511 * Ignore all characters if CREAD is not set.
512 */
513 if ((termios->c_cflag & CREAD) == 0)
514 port->ignore_status_mask |= UART_DUMMY_RSR_RX;
515
516 if (UART_ENABLE_MS(port, termios->c_cflag))
517 pl011_enable_ms(port);
518
519 /* first, disable everything */
520 old_cr = readw(port->membase + UART011_CR);
521 writew(0, port->membase + UART011_CR);
522
523 /* Set baud rate */
524 writew(quot & 0x3f, port->membase + UART011_FBRD);
525 writew(quot >> 6, port->membase + UART011_IBRD);
526
527 /*
528 * ----------v----------v----------v----------v-----
529 * NOTE: MUST BE WRITTEN AFTER UARTLCR_M & UARTLCR_L
530 * ----------^----------^----------^----------^-----
531 */
532 writew(lcr_h, port->membase + UART011_LCRH);
533 writew(old_cr, port->membase + UART011_CR);
534
535 spin_unlock_irqrestore(&port->lock, flags);
536 }
537
538 static const char *pl011_type(struct uart_port *port)
539 {
540 return port->type == PORT_AMBA ? "AMBA/PL011" : NULL;
541 }
542
543 /*
544 * Release the memory region(s) being used by 'port'
545 */
546 static void pl010_release_port(struct uart_port *port)
547 {
548 release_mem_region(port->mapbase, SZ_4K);
549 }
550
551 /*
552 * Request the memory region(s) being used by 'port'
553 */
554 static int pl010_request_port(struct uart_port *port)
555 {
556 return request_mem_region(port->mapbase, SZ_4K, "uart-pl011")
557 != NULL ? 0 : -EBUSY;
558 }
559
560 /*
561 * Configure/autoconfigure the port.
562 */
563 static void pl010_config_port(struct uart_port *port, int flags)
564 {
565 if (flags & UART_CONFIG_TYPE) {
566 port->type = PORT_AMBA;
567 pl010_request_port(port);
568 }
569 }
570
571 /*
572 * verify the new serial_struct (for TIOCSSERIAL).
573 */
574 static int pl010_verify_port(struct uart_port *port, struct serial_struct *ser)
575 {
576 int ret = 0;
577 if (ser->type != PORT_UNKNOWN && ser->type != PORT_AMBA)
578 ret = -EINVAL;
579 if (ser->irq < 0 || ser->irq >= NR_IRQS)
580 ret = -EINVAL;
581 if (ser->baud_base < 9600)
582 ret = -EINVAL;
583 return ret;
584 }
585
586 static struct uart_ops amba_pl011_pops = {
587 .tx_empty = pl01x_tx_empty,
588 .set_mctrl = pl011_set_mctrl,
589 .get_mctrl = pl01x_get_mctrl,
590 .stop_tx = pl011_stop_tx,
591 .start_tx = pl011_start_tx,
592 .stop_rx = pl011_stop_rx,
593 .enable_ms = pl011_enable_ms,
594 .break_ctl = pl011_break_ctl,
595 .startup = pl011_startup,
596 .shutdown = pl011_shutdown,
597 .set_termios = pl011_set_termios,
598 .type = pl011_type,
599 .release_port = pl010_release_port,
600 .request_port = pl010_request_port,
601 .config_port = pl010_config_port,
602 .verify_port = pl010_verify_port,
603 };
604
605 static struct uart_amba_port *amba_ports[UART_NR];
606
607 #ifdef CONFIG_SERIAL_AMBA_PL011_CONSOLE
608
609 static inline void
610 pl011_console_write_char(struct uart_amba_port *uap, char ch)
611 {
612 unsigned int status;
613
614 do {
615 status = readw(uap->port.membase + UART01x_FR);
616 } while (status & UART01x_FR_TXFF);
617 writew(ch, uap->port.membase + UART01x_DR);
618 }
619
620 static void
621 pl011_console_write(struct console *co, const char *s, unsigned int count)
622 {
623 struct uart_amba_port *uap = amba_ports[co->index];
624 unsigned int status, old_cr, new_cr;
625 int i;
626
627 clk_enable(uap->clk);
628
629 /*
630 * First save the CR then disable the interrupts
631 */
632 old_cr = readw(uap->port.membase + UART011_CR);
633 new_cr = old_cr & ~UART011_CR_CTSEN;
634 new_cr |= UART01x_CR_UARTEN | UART011_CR_TXE;
635 writew(new_cr, uap->port.membase + UART011_CR);
636
637 /*
638 * Now, do each character
639 */
640 for (i = 0; i < count; i++) {
641 pl011_console_write_char(uap, s[i]);
642 if (s[i] == '\n')
643 pl011_console_write_char(uap, '\r');
644 }
645
646 /*
647 * Finally, wait for transmitter to become empty
648 * and restore the TCR
649 */
650 do {
651 status = readw(uap->port.membase + UART01x_FR);
652 } while (status & UART01x_FR_BUSY);
653 writew(old_cr, uap->port.membase + UART011_CR);
654
655 clk_disable(uap->clk);
656 }
657
658 static void __init
659 pl011_console_get_options(struct uart_amba_port *uap, int *baud,
660 int *parity, int *bits)
661 {
662 if (readw(uap->port.membase + UART011_CR) & UART01x_CR_UARTEN) {
663 unsigned int lcr_h, ibrd, fbrd;
664
665 lcr_h = readw(uap->port.membase + UART011_LCRH);
666
667 *parity = 'n';
668 if (lcr_h & UART01x_LCRH_PEN) {
669 if (lcr_h & UART01x_LCRH_EPS)
670 *parity = 'e';
671 else
672 *parity = 'o';
673 }
674
675 if ((lcr_h & 0x60) == UART01x_LCRH_WLEN_7)
676 *bits = 7;
677 else
678 *bits = 8;
679
680 ibrd = readw(uap->port.membase + UART011_IBRD);
681 fbrd = readw(uap->port.membase + UART011_FBRD);
682
683 *baud = uap->port.uartclk * 4 / (64 * ibrd + fbrd);
684 }
685 }
686
687 static int __init pl011_console_setup(struct console *co, char *options)
688 {
689 struct uart_amba_port *uap;
690 int baud = 38400;
691 int bits = 8;
692 int parity = 'n';
693 int flow = 'n';
694
695 /*
696 * Check whether an invalid uart number has been specified, and
697 * if so, search for the first available port that does have
698 * console support.
699 */
700 if (co->index >= UART_NR)
701 co->index = 0;
702 uap = amba_ports[co->index];
703
704 uap->port.uartclk = clk_get_rate(uap->clk);
705
706 if (options)
707 uart_parse_options(options, &baud, &parity, &bits, &flow);
708 else
709 pl011_console_get_options(uap, &baud, &parity, &bits);
710
711 return uart_set_options(&uap->port, co, baud, parity, bits, flow);
712 }
713
714 extern struct uart_driver amba_reg;
715 static struct console amba_console = {
716 .name = "ttyAMA",
717 .write = pl011_console_write,
718 .device = uart_console_device,
719 .setup = pl011_console_setup,
720 .flags = CON_PRINTBUFFER,
721 .index = -1,
722 .data = &amba_reg,
723 };
724
725 #define AMBA_CONSOLE (&amba_console)
726 #else
727 #define AMBA_CONSOLE NULL
728 #endif
729
730 static struct uart_driver amba_reg = {
731 .owner = THIS_MODULE,
732 .driver_name = "ttyAMA",
733 .dev_name = "ttyAMA",
734 .major = SERIAL_AMBA_MAJOR,
735 .minor = SERIAL_AMBA_MINOR,
736 .nr = UART_NR,
737 .cons = AMBA_CONSOLE,
738 };
739
740 static int pl011_probe(struct amba_device *dev, void *id)
741 {
742 struct uart_amba_port *uap;
743 void __iomem *base;
744 int i, ret;
745
746 for (i = 0; i < ARRAY_SIZE(amba_ports); i++)
747 if (amba_ports[i] == NULL)
748 break;
749
750 if (i == ARRAY_SIZE(amba_ports)) {
751 ret = -EBUSY;
752 goto out;
753 }
754
755 uap = kmalloc(sizeof(struct uart_amba_port), GFP_KERNEL);
756 if (uap == NULL) {
757 ret = -ENOMEM;
758 goto out;
759 }
760
761 base = ioremap(dev->res.start, PAGE_SIZE);
762 if (!base) {
763 ret = -ENOMEM;
764 goto free;
765 }
766
767 memset(uap, 0, sizeof(struct uart_amba_port));
768 uap->clk = clk_get(&dev->dev, "UARTCLK");
769 if (IS_ERR(uap->clk)) {
770 ret = PTR_ERR(uap->clk);
771 goto unmap;
772 }
773
774 ret = clk_use(uap->clk);
775 if (ret)
776 goto putclk;
777
778 uap->port.dev = &dev->dev;
779 uap->port.mapbase = dev->res.start;
780 uap->port.membase = base;
781 uap->port.iotype = UPIO_MEM;
782 uap->port.irq = dev->irq[0];
783 uap->port.fifosize = 16;
784 uap->port.ops = &amba_pl011_pops;
785 uap->port.flags = UPF_BOOT_AUTOCONF;
786 uap->port.line = i;
787
788 amba_ports[i] = uap;
789
790 amba_set_drvdata(dev, uap);
791 ret = uart_add_one_port(&amba_reg, &uap->port);
792 if (ret) {
793 amba_set_drvdata(dev, NULL);
794 amba_ports[i] = NULL;
795 clk_unuse(uap->clk);
796 putclk:
797 clk_put(uap->clk);
798 unmap:
799 iounmap(base);
800 free:
801 kfree(uap);
802 }
803 out:
804 return ret;
805 }
806
807 static int pl011_remove(struct amba_device *dev)
808 {
809 struct uart_amba_port *uap = amba_get_drvdata(dev);
810 int i;
811
812 amba_set_drvdata(dev, NULL);
813
814 uart_remove_one_port(&amba_reg, &uap->port);
815
816 for (i = 0; i < ARRAY_SIZE(amba_ports); i++)
817 if (amba_ports[i] == uap)
818 amba_ports[i] = NULL;
819
820 iounmap(uap->port.membase);
821 clk_unuse(uap->clk);
822 clk_put(uap->clk);
823 kfree(uap);
824 return 0;
825 }
826
827 static struct amba_id pl011_ids[] __initdata = {
828 {
829 .id = 0x00041011,
830 .mask = 0x000fffff,
831 },
832 { 0, 0 },
833 };
834
835 static struct amba_driver pl011_driver = {
836 .drv = {
837 .name = "uart-pl011",
838 },
839 .id_table = pl011_ids,
840 .probe = pl011_probe,
841 .remove = pl011_remove,
842 };
843
844 static int __init pl011_init(void)
845 {
846 int ret;
847 printk(KERN_INFO "Serial: AMBA PL011 UART driver\n");
848
849 ret = uart_register_driver(&amba_reg);
850 if (ret == 0) {
851 ret = amba_driver_register(&pl011_driver);
852 if (ret)
853 uart_unregister_driver(&amba_reg);
854 }
855 return ret;
856 }
857
858 static void __exit pl011_exit(void)
859 {
860 amba_driver_unregister(&pl011_driver);
861 uart_unregister_driver(&amba_reg);
862 }
863
864 module_init(pl011_init);
865 module_exit(pl011_exit);
866
867 MODULE_AUTHOR("ARM Ltd/Deep Blue Solutions Ltd");
868 MODULE_DESCRIPTION("ARM AMBA serial port driver");
869 MODULE_LICENSE("GPL");
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