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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/sizes.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_DR_ERROR (UART011_DR_OE|UART011_DR_BE|UART011_DR_PE|UART011_DR_FE)
66 #define UART_DUMMY_DR_RX (1 << 16)
67
68 /*
69 * We wrap our port structure around the generic uart_port.
70 */
71 struct uart_amba_port {
72 struct uart_port port;
73 struct clk *clk;
74 unsigned int im; /* interrupt mask */
75 unsigned int old_status;
76 };
77
78 static void pl011_stop_tx(struct uart_port *port)
79 {
80 struct uart_amba_port *uap = (struct uart_amba_port *)port;
81
82 uap->im &= ~UART011_TXIM;
83 writew(uap->im, uap->port.membase + UART011_IMSC);
84 }
85
86 static void pl011_start_tx(struct uart_port *port)
87 {
88 struct uart_amba_port *uap = (struct uart_amba_port *)port;
89
90 uap->im |= UART011_TXIM;
91 writew(uap->im, uap->port.membase + UART011_IMSC);
92 }
93
94 static void pl011_stop_rx(struct uart_port *port)
95 {
96 struct uart_amba_port *uap = (struct uart_amba_port *)port;
97
98 uap->im &= ~(UART011_RXIM|UART011_RTIM|UART011_FEIM|
99 UART011_PEIM|UART011_BEIM|UART011_OEIM);
100 writew(uap->im, uap->port.membase + UART011_IMSC);
101 }
102
103 static void pl011_enable_ms(struct uart_port *port)
104 {
105 struct uart_amba_port *uap = (struct uart_amba_port *)port;
106
107 uap->im |= UART011_RIMIM|UART011_CTSMIM|UART011_DCDMIM|UART011_DSRMIM;
108 writew(uap->im, uap->port.membase + UART011_IMSC);
109 }
110
111 static void
112 #ifdef SUPPORT_SYSRQ
113 pl011_rx_chars(struct uart_amba_port *uap, struct pt_regs *regs)
114 #else
115 pl011_rx_chars(struct uart_amba_port *uap)
116 #endif
117 {
118 struct tty_struct *tty = uap->port.info->tty;
119 unsigned int status, ch, flag, max_count = 256;
120
121 status = readw(uap->port.membase + UART01x_FR);
122 while ((status & UART01x_FR_RXFE) == 0 && max_count--) {
123 if (tty->flip.count >= TTY_FLIPBUF_SIZE) {
124 if (tty->low_latency)
125 tty_flip_buffer_push(tty);
126 /*
127 * If this failed then we will throw away the
128 * bytes but must do so to clear interrupts
129 */
130 }
131
132 ch = readw(uap->port.membase + UART01x_DR) | UART_DUMMY_DR_RX;
133 flag = TTY_NORMAL;
134 uap->port.icount.rx++;
135
136 /*
137 * Note that the error handling code is
138 * out of the main execution path
139 */
140 if (unlikely(ch & UART_DR_ERROR)) {
141 if (ch & UART011_DR_BE) {
142 ch &= ~(UART011_DR_FE | UART011_DR_PE);
143 uap->port.icount.brk++;
144 if (uart_handle_break(&uap->port))
145 goto ignore_char;
146 } else if (ch & UART011_DR_PE)
147 uap->port.icount.parity++;
148 else if (ch & UART011_DR_FE)
149 uap->port.icount.frame++;
150 if (ch & UART011_DR_OE)
151 uap->port.icount.overrun++;
152
153 ch &= uap->port.read_status_mask;
154
155 if (ch & UART011_DR_BE)
156 flag = TTY_BREAK;
157 else if (ch & UART011_DR_PE)
158 flag = TTY_PARITY;
159 else if (ch & UART011_DR_FE)
160 flag = TTY_FRAME;
161 }
162
163 if (uart_handle_sysrq_char(&uap->port, ch & 255, regs))
164 goto ignore_char;
165
166 uart_insert_char(&uap->port, ch, UART011_DR_OE, ch, flag);
167
168 ignore_char:
169 status = readw(uap->port.membase + UART01x_FR);
170 }
171 tty_flip_buffer_push(tty);
172 return;
173 }
174
175 static void pl011_tx_chars(struct uart_amba_port *uap)
176 {
177 struct circ_buf *xmit = &uap->port.info->xmit;
178 int count;
179
180 if (uap->port.x_char) {
181 writew(uap->port.x_char, uap->port.membase + UART01x_DR);
182 uap->port.icount.tx++;
183 uap->port.x_char = 0;
184 return;
185 }
186 if (uart_circ_empty(xmit) || uart_tx_stopped(&uap->port)) {
187 pl011_stop_tx(&uap->port);
188 return;
189 }
190
191 count = uap->port.fifosize >> 1;
192 do {
193 writew(xmit->buf[xmit->tail], uap->port.membase + UART01x_DR);
194 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
195 uap->port.icount.tx++;
196 if (uart_circ_empty(xmit))
197 break;
198 } while (--count > 0);
199
200 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
201 uart_write_wakeup(&uap->port);
202
203 if (uart_circ_empty(xmit))
204 pl011_stop_tx(&uap->port);
205 }
206
207 static void pl011_modem_status(struct uart_amba_port *uap)
208 {
209 unsigned int status, delta;
210
211 status = readw(uap->port.membase + UART01x_FR) & UART01x_FR_MODEM_ANY;
212
213 delta = status ^ uap->old_status;
214 uap->old_status = status;
215
216 if (!delta)
217 return;
218
219 if (delta & UART01x_FR_DCD)
220 uart_handle_dcd_change(&uap->port, status & UART01x_FR_DCD);
221
222 if (delta & UART01x_FR_DSR)
223 uap->port.icount.dsr++;
224
225 if (delta & UART01x_FR_CTS)
226 uart_handle_cts_change(&uap->port, status & UART01x_FR_CTS);
227
228 wake_up_interruptible(&uap->port.info->delta_msr_wait);
229 }
230
231 static irqreturn_t pl011_int(int irq, void *dev_id, struct pt_regs *regs)
232 {
233 struct uart_amba_port *uap = dev_id;
234 unsigned int status, pass_counter = AMBA_ISR_PASS_LIMIT;
235 int handled = 0;
236
237 spin_lock(&uap->port.lock);
238
239 status = readw(uap->port.membase + UART011_MIS);
240 if (status) {
241 do {
242 writew(status & ~(UART011_TXIS|UART011_RTIS|
243 UART011_RXIS),
244 uap->port.membase + UART011_ICR);
245
246 if (status & (UART011_RTIS|UART011_RXIS))
247 #ifdef SUPPORT_SYSRQ
248 pl011_rx_chars(uap, regs);
249 #else
250 pl011_rx_chars(uap);
251 #endif
252 if (status & (UART011_DSRMIS|UART011_DCDMIS|
253 UART011_CTSMIS|UART011_RIMIS))
254 pl011_modem_status(uap);
255 if (status & UART011_TXIS)
256 pl011_tx_chars(uap);
257
258 if (pass_counter-- == 0)
259 break;
260
261 status = readw(uap->port.membase + UART011_MIS);
262 } while (status != 0);
263 handled = 1;
264 }
265
266 spin_unlock(&uap->port.lock);
267
268 return IRQ_RETVAL(handled);
269 }
270
271 static unsigned int pl01x_tx_empty(struct uart_port *port)
272 {
273 struct uart_amba_port *uap = (struct uart_amba_port *)port;
274 unsigned int status = readw(uap->port.membase + UART01x_FR);
275 return status & (UART01x_FR_BUSY|UART01x_FR_TXFF) ? 0 : TIOCSER_TEMT;
276 }
277
278 static unsigned int pl01x_get_mctrl(struct uart_port *port)
279 {
280 struct uart_amba_port *uap = (struct uart_amba_port *)port;
281 unsigned int result = 0;
282 unsigned int status = readw(uap->port.membase + UART01x_FR);
283
284 #define BIT(uartbit, tiocmbit) \
285 if (status & uartbit) \
286 result |= tiocmbit
287
288 BIT(UART01x_FR_DCD, TIOCM_CAR);
289 BIT(UART01x_FR_DSR, TIOCM_DSR);
290 BIT(UART01x_FR_CTS, TIOCM_CTS);
291 BIT(UART011_FR_RI, TIOCM_RNG);
292 #undef BIT
293 return result;
294 }
295
296 static void pl011_set_mctrl(struct uart_port *port, unsigned int mctrl)
297 {
298 struct uart_amba_port *uap = (struct uart_amba_port *)port;
299 unsigned int cr;
300
301 cr = readw(uap->port.membase + UART011_CR);
302
303 #define BIT(tiocmbit, uartbit) \
304 if (mctrl & tiocmbit) \
305 cr |= uartbit; \
306 else \
307 cr &= ~uartbit
308
309 BIT(TIOCM_RTS, UART011_CR_RTS);
310 BIT(TIOCM_DTR, UART011_CR_DTR);
311 BIT(TIOCM_OUT1, UART011_CR_OUT1);
312 BIT(TIOCM_OUT2, UART011_CR_OUT2);
313 BIT(TIOCM_LOOP, UART011_CR_LBE);
314 #undef BIT
315
316 writew(cr, uap->port.membase + UART011_CR);
317 }
318
319 static void pl011_break_ctl(struct uart_port *port, int break_state)
320 {
321 struct uart_amba_port *uap = (struct uart_amba_port *)port;
322 unsigned long flags;
323 unsigned int lcr_h;
324
325 spin_lock_irqsave(&uap->port.lock, flags);
326 lcr_h = readw(uap->port.membase + UART011_LCRH);
327 if (break_state == -1)
328 lcr_h |= UART01x_LCRH_BRK;
329 else
330 lcr_h &= ~UART01x_LCRH_BRK;
331 writew(lcr_h, uap->port.membase + UART011_LCRH);
332 spin_unlock_irqrestore(&uap->port.lock, flags);
333 }
334
335 static int pl011_startup(struct uart_port *port)
336 {
337 struct uart_amba_port *uap = (struct uart_amba_port *)port;
338 unsigned int cr;
339 int retval;
340
341 /*
342 * Try to enable the clock producer.
343 */
344 retval = clk_enable(uap->clk);
345 if (retval)
346 goto out;
347
348 uap->port.uartclk = clk_get_rate(uap->clk);
349
350 /*
351 * Allocate the IRQ
352 */
353 retval = request_irq(uap->port.irq, pl011_int, 0, "uart-pl011", uap);
354 if (retval)
355 goto clk_dis;
356
357 writew(UART011_IFLS_RX4_8|UART011_IFLS_TX4_8,
358 uap->port.membase + UART011_IFLS);
359
360 /*
361 * Provoke TX FIFO interrupt into asserting.
362 */
363 cr = UART01x_CR_UARTEN | UART011_CR_TXE | UART011_CR_LBE;
364 writew(cr, uap->port.membase + UART011_CR);
365 writew(0, uap->port.membase + UART011_FBRD);
366 writew(1, uap->port.membase + UART011_IBRD);
367 writew(0, uap->port.membase + UART011_LCRH);
368 writew(0, uap->port.membase + UART01x_DR);
369 while (readw(uap->port.membase + UART01x_FR) & UART01x_FR_BUSY)
370 barrier();
371
372 cr = UART01x_CR_UARTEN | UART011_CR_RXE | UART011_CR_TXE;
373 writew(cr, uap->port.membase + UART011_CR);
374
375 /*
376 * initialise the old status of the modem signals
377 */
378 uap->old_status = readw(uap->port.membase + UART01x_FR) & UART01x_FR_MODEM_ANY;
379
380 /*
381 * Finally, enable interrupts
382 */
383 spin_lock_irq(&uap->port.lock);
384 uap->im = UART011_RXIM | UART011_RTIM;
385 writew(uap->im, uap->port.membase + UART011_IMSC);
386 spin_unlock_irq(&uap->port.lock);
387
388 return 0;
389
390 clk_dis:
391 clk_disable(uap->clk);
392 out:
393 return retval;
394 }
395
396 static void pl011_shutdown(struct uart_port *port)
397 {
398 struct uart_amba_port *uap = (struct uart_amba_port *)port;
399 unsigned long val;
400
401 /*
402 * disable all interrupts
403 */
404 spin_lock_irq(&uap->port.lock);
405 uap->im = 0;
406 writew(uap->im, uap->port.membase + UART011_IMSC);
407 writew(0xffff, uap->port.membase + UART011_ICR);
408 spin_unlock_irq(&uap->port.lock);
409
410 /*
411 * Free the interrupt
412 */
413 free_irq(uap->port.irq, uap);
414
415 /*
416 * disable the port
417 */
418 writew(UART01x_CR_UARTEN | UART011_CR_TXE, uap->port.membase + UART011_CR);
419
420 /*
421 * disable break condition and fifos
422 */
423 val = readw(uap->port.membase + UART011_LCRH);
424 val &= ~(UART01x_LCRH_BRK | UART01x_LCRH_FEN);
425 writew(val, uap->port.membase + UART011_LCRH);
426
427 /*
428 * Shut down the clock producer
429 */
430 clk_disable(uap->clk);
431 }
432
433 static void
434 pl011_set_termios(struct uart_port *port, struct termios *termios,
435 struct termios *old)
436 {
437 unsigned int lcr_h, old_cr;
438 unsigned long flags;
439 unsigned int baud, quot;
440
441 /*
442 * Ask the core to calculate the divisor for us.
443 */
444 baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk/16);
445 quot = port->uartclk * 4 / baud;
446
447 switch (termios->c_cflag & CSIZE) {
448 case CS5:
449 lcr_h = UART01x_LCRH_WLEN_5;
450 break;
451 case CS6:
452 lcr_h = UART01x_LCRH_WLEN_6;
453 break;
454 case CS7:
455 lcr_h = UART01x_LCRH_WLEN_7;
456 break;
457 default: // CS8
458 lcr_h = UART01x_LCRH_WLEN_8;
459 break;
460 }
461 if (termios->c_cflag & CSTOPB)
462 lcr_h |= UART01x_LCRH_STP2;
463 if (termios->c_cflag & PARENB) {
464 lcr_h |= UART01x_LCRH_PEN;
465 if (!(termios->c_cflag & PARODD))
466 lcr_h |= UART01x_LCRH_EPS;
467 }
468 if (port->fifosize > 1)
469 lcr_h |= UART01x_LCRH_FEN;
470
471 spin_lock_irqsave(&port->lock, flags);
472
473 /*
474 * Update the per-port timeout.
475 */
476 uart_update_timeout(port, termios->c_cflag, baud);
477
478 port->read_status_mask = UART011_DR_OE | 255;
479 if (termios->c_iflag & INPCK)
480 port->read_status_mask |= UART011_DR_FE | UART011_DR_PE;
481 if (termios->c_iflag & (BRKINT | PARMRK))
482 port->read_status_mask |= UART011_DR_BE;
483
484 /*
485 * Characters to ignore
486 */
487 port->ignore_status_mask = 0;
488 if (termios->c_iflag & IGNPAR)
489 port->ignore_status_mask |= UART011_DR_FE | UART011_DR_PE;
490 if (termios->c_iflag & IGNBRK) {
491 port->ignore_status_mask |= UART011_DR_BE;
492 /*
493 * If we're ignoring parity and break indicators,
494 * ignore overruns too (for real raw support).
495 */
496 if (termios->c_iflag & IGNPAR)
497 port->ignore_status_mask |= UART011_DR_OE;
498 }
499
500 /*
501 * Ignore all characters if CREAD is not set.
502 */
503 if ((termios->c_cflag & CREAD) == 0)
504 port->ignore_status_mask |= UART_DUMMY_DR_RX;
505
506 if (UART_ENABLE_MS(port, termios->c_cflag))
507 pl011_enable_ms(port);
508
509 /* first, disable everything */
510 old_cr = readw(port->membase + UART011_CR);
511 writew(0, port->membase + UART011_CR);
512
513 /* Set baud rate */
514 writew(quot & 0x3f, port->membase + UART011_FBRD);
515 writew(quot >> 6, port->membase + UART011_IBRD);
516
517 /*
518 * ----------v----------v----------v----------v-----
519 * NOTE: MUST BE WRITTEN AFTER UARTLCR_M & UARTLCR_L
520 * ----------^----------^----------^----------^-----
521 */
522 writew(lcr_h, port->membase + UART011_LCRH);
523 writew(old_cr, port->membase + UART011_CR);
524
525 spin_unlock_irqrestore(&port->lock, flags);
526 }
527
528 static const char *pl011_type(struct uart_port *port)
529 {
530 return port->type == PORT_AMBA ? "AMBA/PL011" : NULL;
531 }
532
533 /*
534 * Release the memory region(s) being used by 'port'
535 */
536 static void pl010_release_port(struct uart_port *port)
537 {
538 release_mem_region(port->mapbase, SZ_4K);
539 }
540
541 /*
542 * Request the memory region(s) being used by 'port'
543 */
544 static int pl010_request_port(struct uart_port *port)
545 {
546 return request_mem_region(port->mapbase, SZ_4K, "uart-pl011")
547 != NULL ? 0 : -EBUSY;
548 }
549
550 /*
551 * Configure/autoconfigure the port.
552 */
553 static void pl010_config_port(struct uart_port *port, int flags)
554 {
555 if (flags & UART_CONFIG_TYPE) {
556 port->type = PORT_AMBA;
557 pl010_request_port(port);
558 }
559 }
560
561 /*
562 * verify the new serial_struct (for TIOCSSERIAL).
563 */
564 static int pl010_verify_port(struct uart_port *port, struct serial_struct *ser)
565 {
566 int ret = 0;
567 if (ser->type != PORT_UNKNOWN && ser->type != PORT_AMBA)
568 ret = -EINVAL;
569 if (ser->irq < 0 || ser->irq >= NR_IRQS)
570 ret = -EINVAL;
571 if (ser->baud_base < 9600)
572 ret = -EINVAL;
573 return ret;
574 }
575
576 static struct uart_ops amba_pl011_pops = {
577 .tx_empty = pl01x_tx_empty,
578 .set_mctrl = pl011_set_mctrl,
579 .get_mctrl = pl01x_get_mctrl,
580 .stop_tx = pl011_stop_tx,
581 .start_tx = pl011_start_tx,
582 .stop_rx = pl011_stop_rx,
583 .enable_ms = pl011_enable_ms,
584 .break_ctl = pl011_break_ctl,
585 .startup = pl011_startup,
586 .shutdown = pl011_shutdown,
587 .set_termios = pl011_set_termios,
588 .type = pl011_type,
589 .release_port = pl010_release_port,
590 .request_port = pl010_request_port,
591 .config_port = pl010_config_port,
592 .verify_port = pl010_verify_port,
593 };
594
595 static struct uart_amba_port *amba_ports[UART_NR];
596
597 #ifdef CONFIG_SERIAL_AMBA_PL011_CONSOLE
598
599 static inline void
600 pl011_console_write_char(struct uart_amba_port *uap, char ch)
601 {
602 unsigned int status;
603
604 do {
605 status = readw(uap->port.membase + UART01x_FR);
606 } while (status & UART01x_FR_TXFF);
607 writew(ch, uap->port.membase + UART01x_DR);
608 }
609
610 static void
611 pl011_console_write(struct console *co, const char *s, unsigned int count)
612 {
613 struct uart_amba_port *uap = amba_ports[co->index];
614 unsigned int status, old_cr, new_cr;
615 int i;
616
617 clk_enable(uap->clk);
618
619 /*
620 * First save the CR then disable the interrupts
621 */
622 old_cr = readw(uap->port.membase + UART011_CR);
623 new_cr = old_cr & ~UART011_CR_CTSEN;
624 new_cr |= UART01x_CR_UARTEN | UART011_CR_TXE;
625 writew(new_cr, uap->port.membase + UART011_CR);
626
627 /*
628 * Now, do each character
629 */
630 for (i = 0; i < count; i++) {
631 pl011_console_write_char(uap, s[i]);
632 if (s[i] == '\n')
633 pl011_console_write_char(uap, '\r');
634 }
635
636 /*
637 * Finally, wait for transmitter to become empty
638 * and restore the TCR
639 */
640 do {
641 status = readw(uap->port.membase + UART01x_FR);
642 } while (status & UART01x_FR_BUSY);
643 writew(old_cr, uap->port.membase + UART011_CR);
644
645 clk_disable(uap->clk);
646 }
647
648 static void __init
649 pl011_console_get_options(struct uart_amba_port *uap, int *baud,
650 int *parity, int *bits)
651 {
652 if (readw(uap->port.membase + UART011_CR) & UART01x_CR_UARTEN) {
653 unsigned int lcr_h, ibrd, fbrd;
654
655 lcr_h = readw(uap->port.membase + UART011_LCRH);
656
657 *parity = 'n';
658 if (lcr_h & UART01x_LCRH_PEN) {
659 if (lcr_h & UART01x_LCRH_EPS)
660 *parity = 'e';
661 else
662 *parity = 'o';
663 }
664
665 if ((lcr_h & 0x60) == UART01x_LCRH_WLEN_7)
666 *bits = 7;
667 else
668 *bits = 8;
669
670 ibrd = readw(uap->port.membase + UART011_IBRD);
671 fbrd = readw(uap->port.membase + UART011_FBRD);
672
673 *baud = uap->port.uartclk * 4 / (64 * ibrd + fbrd);
674 }
675 }
676
677 static int __init pl011_console_setup(struct console *co, char *options)
678 {
679 struct uart_amba_port *uap;
680 int baud = 38400;
681 int bits = 8;
682 int parity = 'n';
683 int flow = 'n';
684
685 /*
686 * Check whether an invalid uart number has been specified, and
687 * if so, search for the first available port that does have
688 * console support.
689 */
690 if (co->index >= UART_NR)
691 co->index = 0;
692 uap = amba_ports[co->index];
693
694 uap->port.uartclk = clk_get_rate(uap->clk);
695
696 if (options)
697 uart_parse_options(options, &baud, &parity, &bits, &flow);
698 else
699 pl011_console_get_options(uap, &baud, &parity, &bits);
700
701 return uart_set_options(&uap->port, co, baud, parity, bits, flow);
702 }
703
704 static struct uart_driver amba_reg;
705 static struct console amba_console = {
706 .name = "ttyAMA",
707 .write = pl011_console_write,
708 .device = uart_console_device,
709 .setup = pl011_console_setup,
710 .flags = CON_PRINTBUFFER,
711 .index = -1,
712 .data = &amba_reg,
713 };
714
715 #define AMBA_CONSOLE (&amba_console)
716 #else
717 #define AMBA_CONSOLE NULL
718 #endif
719
720 static struct uart_driver amba_reg = {
721 .owner = THIS_MODULE,
722 .driver_name = "ttyAMA",
723 .dev_name = "ttyAMA",
724 .major = SERIAL_AMBA_MAJOR,
725 .minor = SERIAL_AMBA_MINOR,
726 .nr = UART_NR,
727 .cons = AMBA_CONSOLE,
728 };
729
730 static int pl011_probe(struct amba_device *dev, void *id)
731 {
732 struct uart_amba_port *uap;
733 void __iomem *base;
734 int i, ret;
735
736 for (i = 0; i < ARRAY_SIZE(amba_ports); i++)
737 if (amba_ports[i] == NULL)
738 break;
739
740 if (i == ARRAY_SIZE(amba_ports)) {
741 ret = -EBUSY;
742 goto out;
743 }
744
745 uap = kmalloc(sizeof(struct uart_amba_port), GFP_KERNEL);
746 if (uap == NULL) {
747 ret = -ENOMEM;
748 goto out;
749 }
750
751 base = ioremap(dev->res.start, PAGE_SIZE);
752 if (!base) {
753 ret = -ENOMEM;
754 goto free;
755 }
756
757 memset(uap, 0, sizeof(struct uart_amba_port));
758 uap->clk = clk_get(&dev->dev, "UARTCLK");
759 if (IS_ERR(uap->clk)) {
760 ret = PTR_ERR(uap->clk);
761 goto unmap;
762 }
763
764 ret = clk_use(uap->clk);
765 if (ret)
766 goto putclk;
767
768 uap->port.dev = &dev->dev;
769 uap->port.mapbase = dev->res.start;
770 uap->port.membase = base;
771 uap->port.iotype = UPIO_MEM;
772 uap->port.irq = dev->irq[0];
773 uap->port.fifosize = 16;
774 uap->port.ops = &amba_pl011_pops;
775 uap->port.flags = UPF_BOOT_AUTOCONF;
776 uap->port.line = i;
777
778 amba_ports[i] = uap;
779
780 amba_set_drvdata(dev, uap);
781 ret = uart_add_one_port(&amba_reg, &uap->port);
782 if (ret) {
783 amba_set_drvdata(dev, NULL);
784 amba_ports[i] = NULL;
785 clk_unuse(uap->clk);
786 putclk:
787 clk_put(uap->clk);
788 unmap:
789 iounmap(base);
790 free:
791 kfree(uap);
792 }
793 out:
794 return ret;
795 }
796
797 static int pl011_remove(struct amba_device *dev)
798 {
799 struct uart_amba_port *uap = amba_get_drvdata(dev);
800 int i;
801
802 amba_set_drvdata(dev, NULL);
803
804 uart_remove_one_port(&amba_reg, &uap->port);
805
806 for (i = 0; i < ARRAY_SIZE(amba_ports); i++)
807 if (amba_ports[i] == uap)
808 amba_ports[i] = NULL;
809
810 iounmap(uap->port.membase);
811 clk_unuse(uap->clk);
812 clk_put(uap->clk);
813 kfree(uap);
814 return 0;
815 }
816
817 static struct amba_id pl011_ids[] __initdata = {
818 {
819 .id = 0x00041011,
820 .mask = 0x000fffff,
821 },
822 { 0, 0 },
823 };
824
825 static struct amba_driver pl011_driver = {
826 .drv = {
827 .name = "uart-pl011",
828 },
829 .id_table = pl011_ids,
830 .probe = pl011_probe,
831 .remove = pl011_remove,
832 };
833
834 static int __init pl011_init(void)
835 {
836 int ret;
837 printk(KERN_INFO "Serial: AMBA PL011 UART driver\n");
838
839 ret = uart_register_driver(&amba_reg);
840 if (ret == 0) {
841 ret = amba_driver_register(&pl011_driver);
842 if (ret)
843 uart_unregister_driver(&amba_reg);
844 }
845 return ret;
846 }
847
848 static void __exit pl011_exit(void)
849 {
850 amba_driver_unregister(&pl011_driver);
851 uart_unregister_driver(&amba_reg);
852 }
853
854 module_init(pl011_init);
855 module_exit(pl011_exit);
856
857 MODULE_AUTHOR("ARM Ltd/Deep Blue Solutions Ltd");
858 MODULE_DESCRIPTION("ARM AMBA serial port driver");
859 MODULE_LICENSE("GPL");
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