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1// SPDX-License-Identifier: GPL-2.0+
2/*
3 * Driver for AMBA serial ports
4 *
5 * Based on drivers/char/serial.c, by Linus Torvalds, Theodore Ts'o.
6 *
7 * Copyright 1999 ARM Limited
8 * Copyright (C) 2000 Deep Blue Solutions Ltd.
9 *
10 * This is a generic driver for ARM AMBA-type serial ports. They
11 * have a lot of 16550-like features, but are not register compatible.
12 * Note that although they do have CTS, DCD and DSR inputs, they do
13 * not have an RI input, nor do they have DTR or RTS outputs. If
14 * required, these have to be supplied via some other means (eg, GPIO)
15 * and hooked into this driver.
16 */
17
18#if defined(CONFIG_SERIAL_AMBA_PL010_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
19#define SUPPORT_SYSRQ
20#endif
21
22#include <linux/module.h>
23#include <linux/ioport.h>
24#include <linux/init.h>
25#include <linux/console.h>
26#include <linux/sysrq.h>
27#include <linux/device.h>
28#include <linux/tty.h>
29#include <linux/tty_flip.h>
30#include <linux/serial_core.h>
31#include <linux/serial.h>
32#include <linux/amba/bus.h>
33#include <linux/amba/serial.h>
34#include <linux/clk.h>
35#include <linux/slab.h>
36#include <linux/io.h>
37
38#define UART_NR 8
39
40#define SERIAL_AMBA_MAJOR 204
41#define SERIAL_AMBA_MINOR 16
42#define SERIAL_AMBA_NR UART_NR
43
44#define AMBA_ISR_PASS_LIMIT 256
45
46#define UART_RX_DATA(s) (((s) & UART01x_FR_RXFE) == 0)
47#define UART_TX_READY(s) (((s) & UART01x_FR_TXFF) == 0)
48
49#define UART_DUMMY_RSR_RX 256
50#define UART_PORT_SIZE 64
51
52/*
53 * We wrap our port structure around the generic uart_port.
54 */
55struct uart_amba_port {
56 struct uart_port port;
57 struct clk *clk;
58 struct amba_device *dev;
59 struct amba_pl010_data *data;
60 unsigned int old_status;
61};
62
63static void pl010_stop_tx(struct uart_port *port)
64{
65 struct uart_amba_port *uap =
66 container_of(port, struct uart_amba_port, port);
67 unsigned int cr;
68
69 cr = readb(uap->port.membase + UART010_CR);
70 cr &= ~UART010_CR_TIE;
71 writel(cr, uap->port.membase + UART010_CR);
72}
73
74static void pl010_start_tx(struct uart_port *port)
75{
76 struct uart_amba_port *uap =
77 container_of(port, struct uart_amba_port, port);
78 unsigned int cr;
79
80 cr = readb(uap->port.membase + UART010_CR);
81 cr |= UART010_CR_TIE;
82 writel(cr, uap->port.membase + UART010_CR);
83}
84
85static void pl010_stop_rx(struct uart_port *port)
86{
87 struct uart_amba_port *uap =
88 container_of(port, struct uart_amba_port, port);
89 unsigned int cr;
90
91 cr = readb(uap->port.membase + UART010_CR);
92 cr &= ~(UART010_CR_RIE | UART010_CR_RTIE);
93 writel(cr, uap->port.membase + UART010_CR);
94}
95
96static void pl010_disable_ms(struct uart_port *port)
97{
98 struct uart_amba_port *uap = (struct uart_amba_port *)port;
99 unsigned int cr;
100
101 cr = readb(uap->port.membase + UART010_CR);
102 cr &= ~UART010_CR_MSIE;
103 writel(cr, uap->port.membase + UART010_CR);
104}
105
106static void pl010_enable_ms(struct uart_port *port)
107{
108 struct uart_amba_port *uap =
109 container_of(port, struct uart_amba_port, port);
110 unsigned int cr;
111
112 cr = readb(uap->port.membase + UART010_CR);
113 cr |= UART010_CR_MSIE;
114 writel(cr, uap->port.membase + UART010_CR);
115}
116
117static void pl010_rx_chars(struct uart_amba_port *uap)
118{
119 unsigned int status, ch, flag, rsr, max_count = 256;
120
121 status = readb(uap->port.membase + UART01x_FR);
122 while (UART_RX_DATA(status) && max_count--) {
123 ch = readb(uap->port.membase + UART01x_DR);
124 flag = TTY_NORMAL;
125
126 uap->port.icount.rx++;
127
128 /*
129 * Note that the error handling code is
130 * out of the main execution path
131 */
132 rsr = readb(uap->port.membase + UART01x_RSR) | UART_DUMMY_RSR_RX;
133 if (unlikely(rsr & UART01x_RSR_ANY)) {
134 writel(0, uap->port.membase + UART01x_ECR);
135
136 if (rsr & UART01x_RSR_BE) {
137 rsr &= ~(UART01x_RSR_FE | UART01x_RSR_PE);
138 uap->port.icount.brk++;
139 if (uart_handle_break(&uap->port))
140 goto ignore_char;
141 } else if (rsr & UART01x_RSR_PE)
142 uap->port.icount.parity++;
143 else if (rsr & UART01x_RSR_FE)
144 uap->port.icount.frame++;
145 if (rsr & UART01x_RSR_OE)
146 uap->port.icount.overrun++;
147
148 rsr &= uap->port.read_status_mask;
149
150 if (rsr & UART01x_RSR_BE)
151 flag = TTY_BREAK;
152 else if (rsr & UART01x_RSR_PE)
153 flag = TTY_PARITY;
154 else if (rsr & UART01x_RSR_FE)
155 flag = TTY_FRAME;
156 }
157
158 if (uart_handle_sysrq_char(&uap->port, ch))
159 goto ignore_char;
160
161 uart_insert_char(&uap->port, rsr, UART01x_RSR_OE, ch, flag);
162
163 ignore_char:
164 status = readb(uap->port.membase + UART01x_FR);
165 }
166 spin_unlock(&uap->port.lock);
167 tty_flip_buffer_push(&uap->port.state->port);
168 spin_lock(&uap->port.lock);
169}
170
171static void pl010_tx_chars(struct uart_amba_port *uap)
172{
173 struct circ_buf *xmit = &uap->port.state->xmit;
174 int count;
175
176 if (uap->port.x_char) {
177 writel(uap->port.x_char, uap->port.membase + UART01x_DR);
178 uap->port.icount.tx++;
179 uap->port.x_char = 0;
180 return;
181 }
182 if (uart_circ_empty(xmit) || uart_tx_stopped(&uap->port)) {
183 pl010_stop_tx(&uap->port);
184 return;
185 }
186
187 count = uap->port.fifosize >> 1;
188 do {
189 writel(xmit->buf[xmit->tail], uap->port.membase + UART01x_DR);
190 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
191 uap->port.icount.tx++;
192 if (uart_circ_empty(xmit))
193 break;
194 } while (--count > 0);
195
196 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
197 uart_write_wakeup(&uap->port);
198
199 if (uart_circ_empty(xmit))
200 pl010_stop_tx(&uap->port);
201}
202
203static void pl010_modem_status(struct uart_amba_port *uap)
204{
205 unsigned int status, delta;
206
207 writel(0, uap->port.membase + UART010_ICR);
208
209 status = readb(uap->port.membase + UART01x_FR) & UART01x_FR_MODEM_ANY;
210
211 delta = status ^ uap->old_status;
212 uap->old_status = status;
213
214 if (!delta)
215 return;
216
217 if (delta & UART01x_FR_DCD)
218 uart_handle_dcd_change(&uap->port, status & UART01x_FR_DCD);
219
220 if (delta & UART01x_FR_DSR)
221 uap->port.icount.dsr++;
222
223 if (delta & UART01x_FR_CTS)
224 uart_handle_cts_change(&uap->port, status & UART01x_FR_CTS);
225
226 wake_up_interruptible(&uap->port.state->port.delta_msr_wait);
227}
228
229static irqreturn_t pl010_int(int irq, void *dev_id)
230{
231 struct uart_amba_port *uap = dev_id;
232 unsigned int status, pass_counter = AMBA_ISR_PASS_LIMIT;
233 int handled = 0;
234
235 spin_lock(&uap->port.lock);
236
237 status = readb(uap->port.membase + UART010_IIR);
238 if (status) {
239 do {
240 if (status & (UART010_IIR_RTIS | UART010_IIR_RIS))
241 pl010_rx_chars(uap);
242 if (status & UART010_IIR_MIS)
243 pl010_modem_status(uap);
244 if (status & UART010_IIR_TIS)
245 pl010_tx_chars(uap);
246
247 if (pass_counter-- == 0)
248 break;
249
250 status = readb(uap->port.membase + UART010_IIR);
251 } while (status & (UART010_IIR_RTIS | UART010_IIR_RIS |
252 UART010_IIR_TIS));
253 handled = 1;
254 }
255
256 spin_unlock(&uap->port.lock);
257
258 return IRQ_RETVAL(handled);
259}
260
261static unsigned int pl010_tx_empty(struct uart_port *port)
262{
263 struct uart_amba_port *uap =
264 container_of(port, struct uart_amba_port, port);
265 unsigned int status = readb(uap->port.membase + UART01x_FR);
266 return status & UART01x_FR_BUSY ? 0 : TIOCSER_TEMT;
267}
268
269static unsigned int pl010_get_mctrl(struct uart_port *port)
270{
271 struct uart_amba_port *uap =
272 container_of(port, struct uart_amba_port, port);
273 unsigned int result = 0;
274 unsigned int status;
275
276 status = readb(uap->port.membase + UART01x_FR);
277 if (status & UART01x_FR_DCD)
278 result |= TIOCM_CAR;
279 if (status & UART01x_FR_DSR)
280 result |= TIOCM_DSR;
281 if (status & UART01x_FR_CTS)
282 result |= TIOCM_CTS;
283
284 return result;
285}
286
287static void pl010_set_mctrl(struct uart_port *port, unsigned int mctrl)
288{
289 struct uart_amba_port *uap =
290 container_of(port, struct uart_amba_port, port);
291
292 if (uap->data)
293 uap->data->set_mctrl(uap->dev, uap->port.membase, mctrl);
294}
295
296static void pl010_break_ctl(struct uart_port *port, int break_state)
297{
298 struct uart_amba_port *uap =
299 container_of(port, struct uart_amba_port, port);
300 unsigned long flags;
301 unsigned int lcr_h;
302
303 spin_lock_irqsave(&uap->port.lock, flags);
304 lcr_h = readb(uap->port.membase + UART010_LCRH);
305 if (break_state == -1)
306 lcr_h |= UART01x_LCRH_BRK;
307 else
308 lcr_h &= ~UART01x_LCRH_BRK;
309 writel(lcr_h, uap->port.membase + UART010_LCRH);
310 spin_unlock_irqrestore(&uap->port.lock, flags);
311}
312
313static int pl010_startup(struct uart_port *port)
314{
315 struct uart_amba_port *uap =
316 container_of(port, struct uart_amba_port, port);
317 int retval;
318
319 /*
320 * Try to enable the clock producer.
321 */
322 retval = clk_prepare_enable(uap->clk);
323 if (retval)
324 goto out;
325
326 uap->port.uartclk = clk_get_rate(uap->clk);
327
328 /*
329 * Allocate the IRQ
330 */
331 retval = request_irq(uap->port.irq, pl010_int, 0, "uart-pl010", uap);
332 if (retval)
333 goto clk_dis;
334
335 /*
336 * initialise the old status of the modem signals
337 */
338 uap->old_status = readb(uap->port.membase + UART01x_FR) & UART01x_FR_MODEM_ANY;
339
340 /*
341 * Finally, enable interrupts
342 */
343 writel(UART01x_CR_UARTEN | UART010_CR_RIE | UART010_CR_RTIE,
344 uap->port.membase + UART010_CR);
345
346 return 0;
347
348 clk_dis:
349 clk_disable_unprepare(uap->clk);
350 out:
351 return retval;
352}
353
354static void pl010_shutdown(struct uart_port *port)
355{
356 struct uart_amba_port *uap =
357 container_of(port, struct uart_amba_port, port);
358
359 /*
360 * Free the interrupt
361 */
362 free_irq(uap->port.irq, uap);
363
364 /*
365 * disable all interrupts, disable the port
366 */
367 writel(0, uap->port.membase + UART010_CR);
368
369 /* disable break condition and fifos */
370 writel(readb(uap->port.membase + UART010_LCRH) &
371 ~(UART01x_LCRH_BRK | UART01x_LCRH_FEN),
372 uap->port.membase + UART010_LCRH);
373
374 /*
375 * Shut down the clock producer
376 */
377 clk_disable_unprepare(uap->clk);
378}
379
380static void
381pl010_set_termios(struct uart_port *port, struct ktermios *termios,
382 struct ktermios *old)
383{
384 struct uart_amba_port *uap =
385 container_of(port, struct uart_amba_port, port);
386 unsigned int lcr_h, old_cr;
387 unsigned long flags;
388 unsigned int baud, quot;
389
390 /*
391 * Ask the core to calculate the divisor for us.
392 */
393 baud = uart_get_baud_rate(port, termios, old, 0, uap->port.uartclk/16);
394 quot = uart_get_divisor(port, baud);
395
396 switch (termios->c_cflag & CSIZE) {
397 case CS5:
398 lcr_h = UART01x_LCRH_WLEN_5;
399 break;
400 case CS6:
401 lcr_h = UART01x_LCRH_WLEN_6;
402 break;
403 case CS7:
404 lcr_h = UART01x_LCRH_WLEN_7;
405 break;
406 default: // CS8
407 lcr_h = UART01x_LCRH_WLEN_8;
408 break;
409 }
410 if (termios->c_cflag & CSTOPB)
411 lcr_h |= UART01x_LCRH_STP2;
412 if (termios->c_cflag & PARENB) {
413 lcr_h |= UART01x_LCRH_PEN;
414 if (!(termios->c_cflag & PARODD))
415 lcr_h |= UART01x_LCRH_EPS;
416 }
417 if (uap->port.fifosize > 1)
418 lcr_h |= UART01x_LCRH_FEN;
419
420 spin_lock_irqsave(&uap->port.lock, flags);
421
422 /*
423 * Update the per-port timeout.
424 */
425 uart_update_timeout(port, termios->c_cflag, baud);
426
427 uap->port.read_status_mask = UART01x_RSR_OE;
428 if (termios->c_iflag & INPCK)
429 uap->port.read_status_mask |= UART01x_RSR_FE | UART01x_RSR_PE;
430 if (termios->c_iflag & (IGNBRK | BRKINT | PARMRK))
431 uap->port.read_status_mask |= UART01x_RSR_BE;
432
433 /*
434 * Characters to ignore
435 */
436 uap->port.ignore_status_mask = 0;
437 if (termios->c_iflag & IGNPAR)
438 uap->port.ignore_status_mask |= UART01x_RSR_FE | UART01x_RSR_PE;
439 if (termios->c_iflag & IGNBRK) {
440 uap->port.ignore_status_mask |= UART01x_RSR_BE;
441 /*
442 * If we're ignoring parity and break indicators,
443 * ignore overruns too (for real raw support).
444 */
445 if (termios->c_iflag & IGNPAR)
446 uap->port.ignore_status_mask |= UART01x_RSR_OE;
447 }
448
449 /*
450 * Ignore all characters if CREAD is not set.
451 */
452 if ((termios->c_cflag & CREAD) == 0)
453 uap->port.ignore_status_mask |= UART_DUMMY_RSR_RX;
454
455 /* first, disable everything */
456 old_cr = readb(uap->port.membase + UART010_CR) & ~UART010_CR_MSIE;
457
458 if (UART_ENABLE_MS(port, termios->c_cflag))
459 old_cr |= UART010_CR_MSIE;
460
461 writel(0, uap->port.membase + UART010_CR);
462
463 /* Set baud rate */
464 quot -= 1;
465 writel((quot & 0xf00) >> 8, uap->port.membase + UART010_LCRM);
466 writel(quot & 0xff, uap->port.membase + UART010_LCRL);
467
468 /*
469 * ----------v----------v----------v----------v-----
470 * NOTE: MUST BE WRITTEN AFTER UARTLCR_M & UARTLCR_L
471 * ----------^----------^----------^----------^-----
472 */
473 writel(lcr_h, uap->port.membase + UART010_LCRH);
474 writel(old_cr, uap->port.membase + UART010_CR);
475
476 spin_unlock_irqrestore(&uap->port.lock, flags);
477}
478
479static void pl010_set_ldisc(struct uart_port *port, struct ktermios *termios)
480{
481 if (termios->c_line == N_PPS) {
482 port->flags |= UPF_HARDPPS_CD;
483 spin_lock_irq(&port->lock);
484 pl010_enable_ms(port);
485 spin_unlock_irq(&port->lock);
486 } else {
487 port->flags &= ~UPF_HARDPPS_CD;
488 if (!UART_ENABLE_MS(port, termios->c_cflag)) {
489 spin_lock_irq(&port->lock);
490 pl010_disable_ms(port);
491 spin_unlock_irq(&port->lock);
492 }
493 }
494}
495
496static const char *pl010_type(struct uart_port *port)
497{
498 return port->type == PORT_AMBA ? "AMBA" : NULL;
499}
500
501/*
502 * Release the memory region(s) being used by 'port'
503 */
504static void pl010_release_port(struct uart_port *port)
505{
506 release_mem_region(port->mapbase, UART_PORT_SIZE);
507}
508
509/*
510 * Request the memory region(s) being used by 'port'
511 */
512static int pl010_request_port(struct uart_port *port)
513{
514 return request_mem_region(port->mapbase, UART_PORT_SIZE, "uart-pl010")
515 != NULL ? 0 : -EBUSY;
516}
517
518/*
519 * Configure/autoconfigure the port.
520 */
521static void pl010_config_port(struct uart_port *port, int flags)
522{
523 if (flags & UART_CONFIG_TYPE) {
524 port->type = PORT_AMBA;
525 pl010_request_port(port);
526 }
527}
528
529/*
530 * verify the new serial_struct (for TIOCSSERIAL).
531 */
532static int pl010_verify_port(struct uart_port *port, struct serial_struct *ser)
533{
534 int ret = 0;
535 if (ser->type != PORT_UNKNOWN && ser->type != PORT_AMBA)
536 ret = -EINVAL;
537 if (ser->irq < 0 || ser->irq >= nr_irqs)
538 ret = -EINVAL;
539 if (ser->baud_base < 9600)
540 ret = -EINVAL;
541 return ret;
542}
543
544static const struct uart_ops amba_pl010_pops = {
545 .tx_empty = pl010_tx_empty,
546 .set_mctrl = pl010_set_mctrl,
547 .get_mctrl = pl010_get_mctrl,
548 .stop_tx = pl010_stop_tx,
549 .start_tx = pl010_start_tx,
550 .stop_rx = pl010_stop_rx,
551 .enable_ms = pl010_enable_ms,
552 .break_ctl = pl010_break_ctl,
553 .startup = pl010_startup,
554 .shutdown = pl010_shutdown,
555 .set_termios = pl010_set_termios,
556 .set_ldisc = pl010_set_ldisc,
557 .type = pl010_type,
558 .release_port = pl010_release_port,
559 .request_port = pl010_request_port,
560 .config_port = pl010_config_port,
561 .verify_port = pl010_verify_port,
562};
563
564static struct uart_amba_port *amba_ports[UART_NR];
565
566#ifdef CONFIG_SERIAL_AMBA_PL010_CONSOLE
567
568static void pl010_console_putchar(struct uart_port *port, int ch)
569{
570 struct uart_amba_port *uap =
571 container_of(port, struct uart_amba_port, port);
572 unsigned int status;
573
574 do {
575 status = readb(uap->port.membase + UART01x_FR);
576 barrier();
577 } while (!UART_TX_READY(status));
578 writel(ch, uap->port.membase + UART01x_DR);
579}
580
581static void
582pl010_console_write(struct console *co, const char *s, unsigned int count)
583{
584 struct uart_amba_port *uap = amba_ports[co->index];
585 unsigned int status, old_cr;
586
587 clk_enable(uap->clk);
588
589 /*
590 * First save the CR then disable the interrupts
591 */
592 old_cr = readb(uap->port.membase + UART010_CR);
593 writel(UART01x_CR_UARTEN, uap->port.membase + UART010_CR);
594
595 uart_console_write(&uap->port, s, count, pl010_console_putchar);
596
597 /*
598 * Finally, wait for transmitter to become empty
599 * and restore the TCR
600 */
601 do {
602 status = readb(uap->port.membase + UART01x_FR);
603 barrier();
604 } while (status & UART01x_FR_BUSY);
605 writel(old_cr, uap->port.membase + UART010_CR);
606
607 clk_disable(uap->clk);
608}
609
610static void __init
611pl010_console_get_options(struct uart_amba_port *uap, int *baud,
612 int *parity, int *bits)
613{
614 if (readb(uap->port.membase + UART010_CR) & UART01x_CR_UARTEN) {
615 unsigned int lcr_h, quot;
616 lcr_h = readb(uap->port.membase + UART010_LCRH);
617
618 *parity = 'n';
619 if (lcr_h & UART01x_LCRH_PEN) {
620 if (lcr_h & UART01x_LCRH_EPS)
621 *parity = 'e';
622 else
623 *parity = 'o';
624 }
625
626 if ((lcr_h & 0x60) == UART01x_LCRH_WLEN_7)
627 *bits = 7;
628 else
629 *bits = 8;
630
631 quot = readb(uap->port.membase + UART010_LCRL) |
632 readb(uap->port.membase + UART010_LCRM) << 8;
633 *baud = uap->port.uartclk / (16 * (quot + 1));
634 }
635}
636
637static int __init pl010_console_setup(struct console *co, char *options)
638{
639 struct uart_amba_port *uap;
640 int baud = 38400;
641 int bits = 8;
642 int parity = 'n';
643 int flow = 'n';
644 int ret;
645
646 /*
647 * Check whether an invalid uart number has been specified, and
648 * if so, search for the first available port that does have
649 * console support.
650 */
651 if (co->index >= UART_NR)
652 co->index = 0;
653 uap = amba_ports[co->index];
654 if (!uap)
655 return -ENODEV;
656
657 ret = clk_prepare(uap->clk);
658 if (ret)
659 return ret;
660
661 uap->port.uartclk = clk_get_rate(uap->clk);
662
663 if (options)
664 uart_parse_options(options, &baud, &parity, &bits, &flow);
665 else
666 pl010_console_get_options(uap, &baud, &parity, &bits);
667
668 return uart_set_options(&uap->port, co, baud, parity, bits, flow);
669}
670
671static struct uart_driver amba_reg;
672static struct console amba_console = {
673 .name = "ttyAM",
674 .write = pl010_console_write,
675 .device = uart_console_device,
676 .setup = pl010_console_setup,
677 .flags = CON_PRINTBUFFER,
678 .index = -1,
679 .data = &amba_reg,
680};
681
682#define AMBA_CONSOLE &amba_console
683#else
684#define AMBA_CONSOLE NULL
685#endif
686
687static DEFINE_MUTEX(amba_reg_lock);
688static struct uart_driver amba_reg = {
689 .owner = THIS_MODULE,
690 .driver_name = "ttyAM",
691 .dev_name = "ttyAM",
692 .major = SERIAL_AMBA_MAJOR,
693 .minor = SERIAL_AMBA_MINOR,
694 .nr = UART_NR,
695 .cons = AMBA_CONSOLE,
696};
697
698static int pl010_probe(struct amba_device *dev, const struct amba_id *id)
699{
700 struct uart_amba_port *uap;
701 void __iomem *base;
702 int i, ret;
703
704 for (i = 0; i < ARRAY_SIZE(amba_ports); i++)
705 if (amba_ports[i] == NULL)
706 break;
707
708 if (i == ARRAY_SIZE(amba_ports))
709 return -EBUSY;
710
711 uap = devm_kzalloc(&dev->dev, sizeof(struct uart_amba_port),
712 GFP_KERNEL);
713 if (!uap)
714 return -ENOMEM;
715
716 base = devm_ioremap(&dev->dev, dev->res.start,
717 resource_size(&dev->res));
718 if (!base)
719 return -ENOMEM;
720
721 uap->clk = devm_clk_get(&dev->dev, NULL);
722 if (IS_ERR(uap->clk))
723 return PTR_ERR(uap->clk);
724
725 uap->port.dev = &dev->dev;
726 uap->port.mapbase = dev->res.start;
727 uap->port.membase = base;
728 uap->port.iotype = UPIO_MEM;
729 uap->port.irq = dev->irq[0];
730 uap->port.fifosize = 16;
731 uap->port.ops = &amba_pl010_pops;
732 uap->port.flags = UPF_BOOT_AUTOCONF;
733 uap->port.line = i;
734 uap->dev = dev;
735 uap->data = dev_get_platdata(&dev->dev);
736
737 amba_ports[i] = uap;
738
739 amba_set_drvdata(dev, uap);
740
741 mutex_lock(&amba_reg_lock);
742 if (!amba_reg.state) {
743 ret = uart_register_driver(&amba_reg);
744 if (ret < 0) {
745 mutex_unlock(&amba_reg_lock);
746 dev_err(uap->port.dev,
747 "Failed to register AMBA-PL010 driver\n");
748 return ret;
749 }
750 }
751 mutex_unlock(&amba_reg_lock);
752
753 ret = uart_add_one_port(&amba_reg, &uap->port);
754 if (ret)
755 amba_ports[i] = NULL;
756
757 return ret;
758}
759
760static int pl010_remove(struct amba_device *dev)
761{
762 struct uart_amba_port *uap = amba_get_drvdata(dev);
763 int i;
764 bool busy = false;
765
766 uart_remove_one_port(&amba_reg, &uap->port);
767
768 for (i = 0; i < ARRAY_SIZE(amba_ports); i++)
769 if (amba_ports[i] == uap)
770 amba_ports[i] = NULL;
771 else if (amba_ports[i])
772 busy = true;
773
774 if (!busy)
775 uart_unregister_driver(&amba_reg);
776
777 return 0;
778}
779
780#ifdef CONFIG_PM_SLEEP
781static int pl010_suspend(struct device *dev)
782{
783 struct uart_amba_port *uap = dev_get_drvdata(dev);
784
785 if (uap)
786 uart_suspend_port(&amba_reg, &uap->port);
787
788 return 0;
789}
790
791static int pl010_resume(struct device *dev)
792{
793 struct uart_amba_port *uap = dev_get_drvdata(dev);
794
795 if (uap)
796 uart_resume_port(&amba_reg, &uap->port);
797
798 return 0;
799}
800#endif
801
802static SIMPLE_DEV_PM_OPS(pl010_dev_pm_ops, pl010_suspend, pl010_resume);
803
804static const struct amba_id pl010_ids[] = {
805 {
806 .id = 0x00041010,
807 .mask = 0x000fffff,
808 },
809 { 0, 0 },
810};
811
812MODULE_DEVICE_TABLE(amba, pl010_ids);
813
814static struct amba_driver pl010_driver = {
815 .drv = {
816 .name = "uart-pl010",
817 .pm = &pl010_dev_pm_ops,
818 },
819 .id_table = pl010_ids,
820 .probe = pl010_probe,
821 .remove = pl010_remove,
822};
823
824static int __init pl010_init(void)
825{
826 printk(KERN_INFO "Serial: AMBA driver\n");
827
828 return amba_driver_register(&pl010_driver);
829}
830
831static void __exit pl010_exit(void)
832{
833 amba_driver_unregister(&pl010_driver);
834}
835
836module_init(pl010_init);
837module_exit(pl010_exit);
838
839MODULE_AUTHOR("ARM Ltd/Deep Blue Solutions Ltd");
840MODULE_DESCRIPTION("ARM AMBA serial port driver");
841MODULE_LICENSE("GPL");
1/*
2 * Driver for AMBA serial ports
3 *
4 * Based on drivers/char/serial.c, by Linus Torvalds, Theodore Ts'o.
5 *
6 * Copyright 1999 ARM Limited
7 * Copyright (C) 2000 Deep Blue Solutions Ltd.
8 *
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published by
11 * the Free Software Foundation; either version 2 of the License, or
12 * (at your option) any later version.
13 *
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU General Public License for more details.
18 *
19 * You should have received a copy of the GNU General Public License
20 * along with this program; if not, write to the Free Software
21 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
22 *
23 * This is a generic driver for ARM AMBA-type serial ports. They
24 * have a lot of 16550-like features, but are not register compatible.
25 * Note that although they do have CTS, DCD and DSR inputs, they do
26 * not have an RI input, nor do they have DTR or RTS outputs. If
27 * required, these have to be supplied via some other means (eg, GPIO)
28 * and hooked into this driver.
29 */
30
31#if defined(CONFIG_SERIAL_AMBA_PL010_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
32#define SUPPORT_SYSRQ
33#endif
34
35#include <linux/module.h>
36#include <linux/ioport.h>
37#include <linux/init.h>
38#include <linux/console.h>
39#include <linux/sysrq.h>
40#include <linux/device.h>
41#include <linux/tty.h>
42#include <linux/tty_flip.h>
43#include <linux/serial_core.h>
44#include <linux/serial.h>
45#include <linux/amba/bus.h>
46#include <linux/amba/serial.h>
47#include <linux/clk.h>
48#include <linux/slab.h>
49
50#include <asm/io.h>
51
52#define UART_NR 8
53
54#define SERIAL_AMBA_MAJOR 204
55#define SERIAL_AMBA_MINOR 16
56#define SERIAL_AMBA_NR UART_NR
57
58#define AMBA_ISR_PASS_LIMIT 256
59
60#define UART_RX_DATA(s) (((s) & UART01x_FR_RXFE) == 0)
61#define UART_TX_READY(s) (((s) & UART01x_FR_TXFF) == 0)
62
63#define UART_DUMMY_RSR_RX 256
64#define UART_PORT_SIZE 64
65
66/*
67 * We wrap our port structure around the generic uart_port.
68 */
69struct uart_amba_port {
70 struct uart_port port;
71 struct clk *clk;
72 struct amba_device *dev;
73 struct amba_pl010_data *data;
74 unsigned int old_status;
75};
76
77static void pl010_stop_tx(struct uart_port *port)
78{
79 struct uart_amba_port *uap = (struct uart_amba_port *)port;
80 unsigned int cr;
81
82 cr = readb(uap->port.membase + UART010_CR);
83 cr &= ~UART010_CR_TIE;
84 writel(cr, uap->port.membase + UART010_CR);
85}
86
87static void pl010_start_tx(struct uart_port *port)
88{
89 struct uart_amba_port *uap = (struct uart_amba_port *)port;
90 unsigned int cr;
91
92 cr = readb(uap->port.membase + UART010_CR);
93 cr |= UART010_CR_TIE;
94 writel(cr, uap->port.membase + UART010_CR);
95}
96
97static void pl010_stop_rx(struct uart_port *port)
98{
99 struct uart_amba_port *uap = (struct uart_amba_port *)port;
100 unsigned int cr;
101
102 cr = readb(uap->port.membase + UART010_CR);
103 cr &= ~(UART010_CR_RIE | UART010_CR_RTIE);
104 writel(cr, uap->port.membase + UART010_CR);
105}
106
107static void pl010_enable_ms(struct uart_port *port)
108{
109 struct uart_amba_port *uap = (struct uart_amba_port *)port;
110 unsigned int cr;
111
112 cr = readb(uap->port.membase + UART010_CR);
113 cr |= UART010_CR_MSIE;
114 writel(cr, uap->port.membase + UART010_CR);
115}
116
117static void pl010_rx_chars(struct uart_amba_port *uap)
118{
119 struct tty_struct *tty = uap->port.state->port.tty;
120 unsigned int status, ch, flag, rsr, max_count = 256;
121
122 status = readb(uap->port.membase + UART01x_FR);
123 while (UART_RX_DATA(status) && max_count--) {
124 ch = readb(uap->port.membase + UART01x_DR);
125 flag = TTY_NORMAL;
126
127 uap->port.icount.rx++;
128
129 /*
130 * Note that the error handling code is
131 * out of the main execution path
132 */
133 rsr = readb(uap->port.membase + UART01x_RSR) | UART_DUMMY_RSR_RX;
134 if (unlikely(rsr & UART01x_RSR_ANY)) {
135 writel(0, uap->port.membase + UART01x_ECR);
136
137 if (rsr & UART01x_RSR_BE) {
138 rsr &= ~(UART01x_RSR_FE | UART01x_RSR_PE);
139 uap->port.icount.brk++;
140 if (uart_handle_break(&uap->port))
141 goto ignore_char;
142 } else if (rsr & UART01x_RSR_PE)
143 uap->port.icount.parity++;
144 else if (rsr & UART01x_RSR_FE)
145 uap->port.icount.frame++;
146 if (rsr & UART01x_RSR_OE)
147 uap->port.icount.overrun++;
148
149 rsr &= uap->port.read_status_mask;
150
151 if (rsr & UART01x_RSR_BE)
152 flag = TTY_BREAK;
153 else if (rsr & UART01x_RSR_PE)
154 flag = TTY_PARITY;
155 else if (rsr & UART01x_RSR_FE)
156 flag = TTY_FRAME;
157 }
158
159 if (uart_handle_sysrq_char(&uap->port, ch))
160 goto ignore_char;
161
162 uart_insert_char(&uap->port, rsr, UART01x_RSR_OE, ch, flag);
163
164 ignore_char:
165 status = readb(uap->port.membase + UART01x_FR);
166 }
167 spin_unlock(&uap->port.lock);
168 tty_flip_buffer_push(tty);
169 spin_lock(&uap->port.lock);
170}
171
172static void pl010_tx_chars(struct uart_amba_port *uap)
173{
174 struct circ_buf *xmit = &uap->port.state->xmit;
175 int count;
176
177 if (uap->port.x_char) {
178 writel(uap->port.x_char, uap->port.membase + UART01x_DR);
179 uap->port.icount.tx++;
180 uap->port.x_char = 0;
181 return;
182 }
183 if (uart_circ_empty(xmit) || uart_tx_stopped(&uap->port)) {
184 pl010_stop_tx(&uap->port);
185 return;
186 }
187
188 count = uap->port.fifosize >> 1;
189 do {
190 writel(xmit->buf[xmit->tail], uap->port.membase + UART01x_DR);
191 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
192 uap->port.icount.tx++;
193 if (uart_circ_empty(xmit))
194 break;
195 } while (--count > 0);
196
197 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
198 uart_write_wakeup(&uap->port);
199
200 if (uart_circ_empty(xmit))
201 pl010_stop_tx(&uap->port);
202}
203
204static void pl010_modem_status(struct uart_amba_port *uap)
205{
206 unsigned int status, delta;
207
208 writel(0, uap->port.membase + UART010_ICR);
209
210 status = readb(uap->port.membase + UART01x_FR) & UART01x_FR_MODEM_ANY;
211
212 delta = status ^ uap->old_status;
213 uap->old_status = status;
214
215 if (!delta)
216 return;
217
218 if (delta & UART01x_FR_DCD)
219 uart_handle_dcd_change(&uap->port, status & UART01x_FR_DCD);
220
221 if (delta & UART01x_FR_DSR)
222 uap->port.icount.dsr++;
223
224 if (delta & UART01x_FR_CTS)
225 uart_handle_cts_change(&uap->port, status & UART01x_FR_CTS);
226
227 wake_up_interruptible(&uap->port.state->port.delta_msr_wait);
228}
229
230static irqreturn_t pl010_int(int irq, void *dev_id)
231{
232 struct uart_amba_port *uap = dev_id;
233 unsigned int status, pass_counter = AMBA_ISR_PASS_LIMIT;
234 int handled = 0;
235
236 spin_lock(&uap->port.lock);
237
238 status = readb(uap->port.membase + UART010_IIR);
239 if (status) {
240 do {
241 if (status & (UART010_IIR_RTIS | UART010_IIR_RIS))
242 pl010_rx_chars(uap);
243 if (status & UART010_IIR_MIS)
244 pl010_modem_status(uap);
245 if (status & UART010_IIR_TIS)
246 pl010_tx_chars(uap);
247
248 if (pass_counter-- == 0)
249 break;
250
251 status = readb(uap->port.membase + UART010_IIR);
252 } while (status & (UART010_IIR_RTIS | UART010_IIR_RIS |
253 UART010_IIR_TIS));
254 handled = 1;
255 }
256
257 spin_unlock(&uap->port.lock);
258
259 return IRQ_RETVAL(handled);
260}
261
262static unsigned int pl010_tx_empty(struct uart_port *port)
263{
264 struct uart_amba_port *uap = (struct uart_amba_port *)port;
265 unsigned int status = readb(uap->port.membase + UART01x_FR);
266 return status & UART01x_FR_BUSY ? 0 : TIOCSER_TEMT;
267}
268
269static unsigned int pl010_get_mctrl(struct uart_port *port)
270{
271 struct uart_amba_port *uap = (struct uart_amba_port *)port;
272 unsigned int result = 0;
273 unsigned int status;
274
275 status = readb(uap->port.membase + UART01x_FR);
276 if (status & UART01x_FR_DCD)
277 result |= TIOCM_CAR;
278 if (status & UART01x_FR_DSR)
279 result |= TIOCM_DSR;
280 if (status & UART01x_FR_CTS)
281 result |= TIOCM_CTS;
282
283 return result;
284}
285
286static void pl010_set_mctrl(struct uart_port *port, unsigned int mctrl)
287{
288 struct uart_amba_port *uap = (struct uart_amba_port *)port;
289
290 if (uap->data)
291 uap->data->set_mctrl(uap->dev, uap->port.membase, mctrl);
292}
293
294static void pl010_break_ctl(struct uart_port *port, int break_state)
295{
296 struct uart_amba_port *uap = (struct uart_amba_port *)port;
297 unsigned long flags;
298 unsigned int lcr_h;
299
300 spin_lock_irqsave(&uap->port.lock, flags);
301 lcr_h = readb(uap->port.membase + UART010_LCRH);
302 if (break_state == -1)
303 lcr_h |= UART01x_LCRH_BRK;
304 else
305 lcr_h &= ~UART01x_LCRH_BRK;
306 writel(lcr_h, uap->port.membase + UART010_LCRH);
307 spin_unlock_irqrestore(&uap->port.lock, flags);
308}
309
310static int pl010_startup(struct uart_port *port)
311{
312 struct uart_amba_port *uap = (struct uart_amba_port *)port;
313 int retval;
314
315 /*
316 * Try to enable the clock producer.
317 */
318 retval = clk_enable(uap->clk);
319 if (retval)
320 goto out;
321
322 uap->port.uartclk = clk_get_rate(uap->clk);
323
324 /*
325 * Allocate the IRQ
326 */
327 retval = request_irq(uap->port.irq, pl010_int, 0, "uart-pl010", uap);
328 if (retval)
329 goto clk_dis;
330
331 /*
332 * initialise the old status of the modem signals
333 */
334 uap->old_status = readb(uap->port.membase + UART01x_FR) & UART01x_FR_MODEM_ANY;
335
336 /*
337 * Finally, enable interrupts
338 */
339 writel(UART01x_CR_UARTEN | UART010_CR_RIE | UART010_CR_RTIE,
340 uap->port.membase + UART010_CR);
341
342 return 0;
343
344 clk_dis:
345 clk_disable(uap->clk);
346 out:
347 return retval;
348}
349
350static void pl010_shutdown(struct uart_port *port)
351{
352 struct uart_amba_port *uap = (struct uart_amba_port *)port;
353
354 /*
355 * Free the interrupt
356 */
357 free_irq(uap->port.irq, uap);
358
359 /*
360 * disable all interrupts, disable the port
361 */
362 writel(0, uap->port.membase + UART010_CR);
363
364 /* disable break condition and fifos */
365 writel(readb(uap->port.membase + UART010_LCRH) &
366 ~(UART01x_LCRH_BRK | UART01x_LCRH_FEN),
367 uap->port.membase + UART010_LCRH);
368
369 /*
370 * Shut down the clock producer
371 */
372 clk_disable(uap->clk);
373}
374
375static void
376pl010_set_termios(struct uart_port *port, struct ktermios *termios,
377 struct ktermios *old)
378{
379 struct uart_amba_port *uap = (struct uart_amba_port *)port;
380 unsigned int lcr_h, old_cr;
381 unsigned long flags;
382 unsigned int baud, quot;
383
384 /*
385 * Ask the core to calculate the divisor for us.
386 */
387 baud = uart_get_baud_rate(port, termios, old, 0, uap->port.uartclk/16);
388 quot = uart_get_divisor(port, baud);
389
390 switch (termios->c_cflag & CSIZE) {
391 case CS5:
392 lcr_h = UART01x_LCRH_WLEN_5;
393 break;
394 case CS6:
395 lcr_h = UART01x_LCRH_WLEN_6;
396 break;
397 case CS7:
398 lcr_h = UART01x_LCRH_WLEN_7;
399 break;
400 default: // CS8
401 lcr_h = UART01x_LCRH_WLEN_8;
402 break;
403 }
404 if (termios->c_cflag & CSTOPB)
405 lcr_h |= UART01x_LCRH_STP2;
406 if (termios->c_cflag & PARENB) {
407 lcr_h |= UART01x_LCRH_PEN;
408 if (!(termios->c_cflag & PARODD))
409 lcr_h |= UART01x_LCRH_EPS;
410 }
411 if (uap->port.fifosize > 1)
412 lcr_h |= UART01x_LCRH_FEN;
413
414 spin_lock_irqsave(&uap->port.lock, flags);
415
416 /*
417 * Update the per-port timeout.
418 */
419 uart_update_timeout(port, termios->c_cflag, baud);
420
421 uap->port.read_status_mask = UART01x_RSR_OE;
422 if (termios->c_iflag & INPCK)
423 uap->port.read_status_mask |= UART01x_RSR_FE | UART01x_RSR_PE;
424 if (termios->c_iflag & (BRKINT | PARMRK))
425 uap->port.read_status_mask |= UART01x_RSR_BE;
426
427 /*
428 * Characters to ignore
429 */
430 uap->port.ignore_status_mask = 0;
431 if (termios->c_iflag & IGNPAR)
432 uap->port.ignore_status_mask |= UART01x_RSR_FE | UART01x_RSR_PE;
433 if (termios->c_iflag & IGNBRK) {
434 uap->port.ignore_status_mask |= UART01x_RSR_BE;
435 /*
436 * If we're ignoring parity and break indicators,
437 * ignore overruns too (for real raw support).
438 */
439 if (termios->c_iflag & IGNPAR)
440 uap->port.ignore_status_mask |= UART01x_RSR_OE;
441 }
442
443 /*
444 * Ignore all characters if CREAD is not set.
445 */
446 if ((termios->c_cflag & CREAD) == 0)
447 uap->port.ignore_status_mask |= UART_DUMMY_RSR_RX;
448
449 /* first, disable everything */
450 old_cr = readb(uap->port.membase + UART010_CR) & ~UART010_CR_MSIE;
451
452 if (UART_ENABLE_MS(port, termios->c_cflag))
453 old_cr |= UART010_CR_MSIE;
454
455 writel(0, uap->port.membase + UART010_CR);
456
457 /* Set baud rate */
458 quot -= 1;
459 writel((quot & 0xf00) >> 8, uap->port.membase + UART010_LCRM);
460 writel(quot & 0xff, uap->port.membase + UART010_LCRL);
461
462 /*
463 * ----------v----------v----------v----------v-----
464 * NOTE: MUST BE WRITTEN AFTER UARTLCR_M & UARTLCR_L
465 * ----------^----------^----------^----------^-----
466 */
467 writel(lcr_h, uap->port.membase + UART010_LCRH);
468 writel(old_cr, uap->port.membase + UART010_CR);
469
470 spin_unlock_irqrestore(&uap->port.lock, flags);
471}
472
473static void pl010_set_ldisc(struct uart_port *port, int new)
474{
475 if (new == N_PPS) {
476 port->flags |= UPF_HARDPPS_CD;
477 pl010_enable_ms(port);
478 } else
479 port->flags &= ~UPF_HARDPPS_CD;
480}
481
482static const char *pl010_type(struct uart_port *port)
483{
484 return port->type == PORT_AMBA ? "AMBA" : NULL;
485}
486
487/*
488 * Release the memory region(s) being used by 'port'
489 */
490static void pl010_release_port(struct uart_port *port)
491{
492 release_mem_region(port->mapbase, UART_PORT_SIZE);
493}
494
495/*
496 * Request the memory region(s) being used by 'port'
497 */
498static int pl010_request_port(struct uart_port *port)
499{
500 return request_mem_region(port->mapbase, UART_PORT_SIZE, "uart-pl010")
501 != NULL ? 0 : -EBUSY;
502}
503
504/*
505 * Configure/autoconfigure the port.
506 */
507static void pl010_config_port(struct uart_port *port, int flags)
508{
509 if (flags & UART_CONFIG_TYPE) {
510 port->type = PORT_AMBA;
511 pl010_request_port(port);
512 }
513}
514
515/*
516 * verify the new serial_struct (for TIOCSSERIAL).
517 */
518static int pl010_verify_port(struct uart_port *port, struct serial_struct *ser)
519{
520 int ret = 0;
521 if (ser->type != PORT_UNKNOWN && ser->type != PORT_AMBA)
522 ret = -EINVAL;
523 if (ser->irq < 0 || ser->irq >= nr_irqs)
524 ret = -EINVAL;
525 if (ser->baud_base < 9600)
526 ret = -EINVAL;
527 return ret;
528}
529
530static struct uart_ops amba_pl010_pops = {
531 .tx_empty = pl010_tx_empty,
532 .set_mctrl = pl010_set_mctrl,
533 .get_mctrl = pl010_get_mctrl,
534 .stop_tx = pl010_stop_tx,
535 .start_tx = pl010_start_tx,
536 .stop_rx = pl010_stop_rx,
537 .enable_ms = pl010_enable_ms,
538 .break_ctl = pl010_break_ctl,
539 .startup = pl010_startup,
540 .shutdown = pl010_shutdown,
541 .set_termios = pl010_set_termios,
542 .set_ldisc = pl010_set_ldisc,
543 .type = pl010_type,
544 .release_port = pl010_release_port,
545 .request_port = pl010_request_port,
546 .config_port = pl010_config_port,
547 .verify_port = pl010_verify_port,
548};
549
550static struct uart_amba_port *amba_ports[UART_NR];
551
552#ifdef CONFIG_SERIAL_AMBA_PL010_CONSOLE
553
554static void pl010_console_putchar(struct uart_port *port, int ch)
555{
556 struct uart_amba_port *uap = (struct uart_amba_port *)port;
557 unsigned int status;
558
559 do {
560 status = readb(uap->port.membase + UART01x_FR);
561 barrier();
562 } while (!UART_TX_READY(status));
563 writel(ch, uap->port.membase + UART01x_DR);
564}
565
566static void
567pl010_console_write(struct console *co, const char *s, unsigned int count)
568{
569 struct uart_amba_port *uap = amba_ports[co->index];
570 unsigned int status, old_cr;
571
572 clk_enable(uap->clk);
573
574 /*
575 * First save the CR then disable the interrupts
576 */
577 old_cr = readb(uap->port.membase + UART010_CR);
578 writel(UART01x_CR_UARTEN, uap->port.membase + UART010_CR);
579
580 uart_console_write(&uap->port, s, count, pl010_console_putchar);
581
582 /*
583 * Finally, wait for transmitter to become empty
584 * and restore the TCR
585 */
586 do {
587 status = readb(uap->port.membase + UART01x_FR);
588 barrier();
589 } while (status & UART01x_FR_BUSY);
590 writel(old_cr, uap->port.membase + UART010_CR);
591
592 clk_disable(uap->clk);
593}
594
595static void __init
596pl010_console_get_options(struct uart_amba_port *uap, int *baud,
597 int *parity, int *bits)
598{
599 if (readb(uap->port.membase + UART010_CR) & UART01x_CR_UARTEN) {
600 unsigned int lcr_h, quot;
601 lcr_h = readb(uap->port.membase + UART010_LCRH);
602
603 *parity = 'n';
604 if (lcr_h & UART01x_LCRH_PEN) {
605 if (lcr_h & UART01x_LCRH_EPS)
606 *parity = 'e';
607 else
608 *parity = 'o';
609 }
610
611 if ((lcr_h & 0x60) == UART01x_LCRH_WLEN_7)
612 *bits = 7;
613 else
614 *bits = 8;
615
616 quot = readb(uap->port.membase + UART010_LCRL) |
617 readb(uap->port.membase + UART010_LCRM) << 8;
618 *baud = uap->port.uartclk / (16 * (quot + 1));
619 }
620}
621
622static int __init pl010_console_setup(struct console *co, char *options)
623{
624 struct uart_amba_port *uap;
625 int baud = 38400;
626 int bits = 8;
627 int parity = 'n';
628 int flow = 'n';
629
630 /*
631 * Check whether an invalid uart number has been specified, and
632 * if so, search for the first available port that does have
633 * console support.
634 */
635 if (co->index >= UART_NR)
636 co->index = 0;
637 uap = amba_ports[co->index];
638 if (!uap)
639 return -ENODEV;
640
641 uap->port.uartclk = clk_get_rate(uap->clk);
642
643 if (options)
644 uart_parse_options(options, &baud, &parity, &bits, &flow);
645 else
646 pl010_console_get_options(uap, &baud, &parity, &bits);
647
648 return uart_set_options(&uap->port, co, baud, parity, bits, flow);
649}
650
651static struct uart_driver amba_reg;
652static struct console amba_console = {
653 .name = "ttyAM",
654 .write = pl010_console_write,
655 .device = uart_console_device,
656 .setup = pl010_console_setup,
657 .flags = CON_PRINTBUFFER,
658 .index = -1,
659 .data = &amba_reg,
660};
661
662#define AMBA_CONSOLE &amba_console
663#else
664#define AMBA_CONSOLE NULL
665#endif
666
667static struct uart_driver amba_reg = {
668 .owner = THIS_MODULE,
669 .driver_name = "ttyAM",
670 .dev_name = "ttyAM",
671 .major = SERIAL_AMBA_MAJOR,
672 .minor = SERIAL_AMBA_MINOR,
673 .nr = UART_NR,
674 .cons = AMBA_CONSOLE,
675};
676
677static int pl010_probe(struct amba_device *dev, const struct amba_id *id)
678{
679 struct uart_amba_port *uap;
680 void __iomem *base;
681 int i, ret;
682
683 for (i = 0; i < ARRAY_SIZE(amba_ports); i++)
684 if (amba_ports[i] == NULL)
685 break;
686
687 if (i == ARRAY_SIZE(amba_ports)) {
688 ret = -EBUSY;
689 goto out;
690 }
691
692 uap = kzalloc(sizeof(struct uart_amba_port), GFP_KERNEL);
693 if (!uap) {
694 ret = -ENOMEM;
695 goto out;
696 }
697
698 base = ioremap(dev->res.start, resource_size(&dev->res));
699 if (!base) {
700 ret = -ENOMEM;
701 goto free;
702 }
703
704 uap->clk = clk_get(&dev->dev, NULL);
705 if (IS_ERR(uap->clk)) {
706 ret = PTR_ERR(uap->clk);
707 goto unmap;
708 }
709
710 uap->port.dev = &dev->dev;
711 uap->port.mapbase = dev->res.start;
712 uap->port.membase = base;
713 uap->port.iotype = UPIO_MEM;
714 uap->port.irq = dev->irq[0];
715 uap->port.fifosize = 16;
716 uap->port.ops = &amba_pl010_pops;
717 uap->port.flags = UPF_BOOT_AUTOCONF;
718 uap->port.line = i;
719 uap->dev = dev;
720 uap->data = dev->dev.platform_data;
721
722 amba_ports[i] = uap;
723
724 amba_set_drvdata(dev, uap);
725 ret = uart_add_one_port(&amba_reg, &uap->port);
726 if (ret) {
727 amba_set_drvdata(dev, NULL);
728 amba_ports[i] = NULL;
729 clk_put(uap->clk);
730 unmap:
731 iounmap(base);
732 free:
733 kfree(uap);
734 }
735 out:
736 return ret;
737}
738
739static int pl010_remove(struct amba_device *dev)
740{
741 struct uart_amba_port *uap = amba_get_drvdata(dev);
742 int i;
743
744 amba_set_drvdata(dev, NULL);
745
746 uart_remove_one_port(&amba_reg, &uap->port);
747
748 for (i = 0; i < ARRAY_SIZE(amba_ports); i++)
749 if (amba_ports[i] == uap)
750 amba_ports[i] = NULL;
751
752 iounmap(uap->port.membase);
753 clk_put(uap->clk);
754 kfree(uap);
755 return 0;
756}
757
758static int pl010_suspend(struct amba_device *dev, pm_message_t state)
759{
760 struct uart_amba_port *uap = amba_get_drvdata(dev);
761
762 if (uap)
763 uart_suspend_port(&amba_reg, &uap->port);
764
765 return 0;
766}
767
768static int pl010_resume(struct amba_device *dev)
769{
770 struct uart_amba_port *uap = amba_get_drvdata(dev);
771
772 if (uap)
773 uart_resume_port(&amba_reg, &uap->port);
774
775 return 0;
776}
777
778static struct amba_id pl010_ids[] = {
779 {
780 .id = 0x00041010,
781 .mask = 0x000fffff,
782 },
783 { 0, 0 },
784};
785
786static struct amba_driver pl010_driver = {
787 .drv = {
788 .name = "uart-pl010",
789 },
790 .id_table = pl010_ids,
791 .probe = pl010_probe,
792 .remove = pl010_remove,
793 .suspend = pl010_suspend,
794 .resume = pl010_resume,
795};
796
797static int __init pl010_init(void)
798{
799 int ret;
800
801 printk(KERN_INFO "Serial: AMBA driver\n");
802
803 ret = uart_register_driver(&amba_reg);
804 if (ret == 0) {
805 ret = amba_driver_register(&pl010_driver);
806 if (ret)
807 uart_unregister_driver(&amba_reg);
808 }
809 return ret;
810}
811
812static void __exit pl010_exit(void)
813{
814 amba_driver_unregister(&pl010_driver);
815 uart_unregister_driver(&amba_reg);
816}
817
818module_init(pl010_init);
819module_exit(pl010_exit);
820
821MODULE_AUTHOR("ARM Ltd/Deep Blue Solutions Ltd");
822MODULE_DESCRIPTION("ARM AMBA serial port driver");
823MODULE_LICENSE("GPL");