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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 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 = (struct uart_amba_port *)port;
264 unsigned int status = readb(uap->port.membase + UART01x_FR);
265 return status & UART01x_FR_BUSY ? 0 : TIOCSER_TEMT;
266}
267
268static unsigned int pl010_get_mctrl(struct uart_port *port)
269{
270 struct uart_amba_port *uap = (struct uart_amba_port *)port;
271 unsigned int result = 0;
272 unsigned int status;
273
274 status = readb(uap->port.membase + UART01x_FR);
275 if (status & UART01x_FR_DCD)
276 result |= TIOCM_CAR;
277 if (status & UART01x_FR_DSR)
278 result |= TIOCM_DSR;
279 if (status & UART01x_FR_CTS)
280 result |= TIOCM_CTS;
281
282 return result;
283}
284
285static void pl010_set_mctrl(struct uart_port *port, unsigned int mctrl)
286{
287 struct uart_amba_port *uap = (struct uart_amba_port *)port;
288
289 if (uap->data)
290 uap->data->set_mctrl(uap->dev, uap->port.membase, mctrl);
291}
292
293static void pl010_break_ctl(struct uart_port *port, int break_state)
294{
295 struct uart_amba_port *uap = (struct uart_amba_port *)port;
296 unsigned long flags;
297 unsigned int lcr_h;
298
299 spin_lock_irqsave(&uap->port.lock, flags);
300 lcr_h = readb(uap->port.membase + UART010_LCRH);
301 if (break_state == -1)
302 lcr_h |= UART01x_LCRH_BRK;
303 else
304 lcr_h &= ~UART01x_LCRH_BRK;
305 writel(lcr_h, uap->port.membase + UART010_LCRH);
306 spin_unlock_irqrestore(&uap->port.lock, flags);
307}
308
309static int pl010_startup(struct uart_port *port)
310{
311 struct uart_amba_port *uap = (struct uart_amba_port *)port;
312 int retval;
313
314 /*
315 * Try to enable the clock producer.
316 */
317 retval = clk_prepare_enable(uap->clk);
318 if (retval)
319 goto out;
320
321 uap->port.uartclk = clk_get_rate(uap->clk);
322
323 /*
324 * Allocate the IRQ
325 */
326 retval = request_irq(uap->port.irq, pl010_int, 0, "uart-pl010", uap);
327 if (retval)
328 goto clk_dis;
329
330 /*
331 * initialise the old status of the modem signals
332 */
333 uap->old_status = readb(uap->port.membase + UART01x_FR) & UART01x_FR_MODEM_ANY;
334
335 /*
336 * Finally, enable interrupts
337 */
338 writel(UART01x_CR_UARTEN | UART010_CR_RIE | UART010_CR_RTIE,
339 uap->port.membase + UART010_CR);
340
341 return 0;
342
343 clk_dis:
344 clk_disable_unprepare(uap->clk);
345 out:
346 return retval;
347}
348
349static void pl010_shutdown(struct uart_port *port)
350{
351 struct uart_amba_port *uap = (struct uart_amba_port *)port;
352
353 /*
354 * Free the interrupt
355 */
356 free_irq(uap->port.irq, uap);
357
358 /*
359 * disable all interrupts, disable the port
360 */
361 writel(0, uap->port.membase + UART010_CR);
362
363 /* disable break condition and fifos */
364 writel(readb(uap->port.membase + UART010_LCRH) &
365 ~(UART01x_LCRH_BRK | UART01x_LCRH_FEN),
366 uap->port.membase + UART010_LCRH);
367
368 /*
369 * Shut down the clock producer
370 */
371 clk_disable_unprepare(uap->clk);
372}
373
374static void
375pl010_set_termios(struct uart_port *port, struct ktermios *termios,
376 struct ktermios *old)
377{
378 struct uart_amba_port *uap = (struct uart_amba_port *)port;
379 unsigned int lcr_h, old_cr;
380 unsigned long flags;
381 unsigned int baud, quot;
382
383 /*
384 * Ask the core to calculate the divisor for us.
385 */
386 baud = uart_get_baud_rate(port, termios, old, 0, uap->port.uartclk/16);
387 quot = uart_get_divisor(port, baud);
388
389 switch (termios->c_cflag & CSIZE) {
390 case CS5:
391 lcr_h = UART01x_LCRH_WLEN_5;
392 break;
393 case CS6:
394 lcr_h = UART01x_LCRH_WLEN_6;
395 break;
396 case CS7:
397 lcr_h = UART01x_LCRH_WLEN_7;
398 break;
399 default: // CS8
400 lcr_h = UART01x_LCRH_WLEN_8;
401 break;
402 }
403 if (termios->c_cflag & CSTOPB)
404 lcr_h |= UART01x_LCRH_STP2;
405 if (termios->c_cflag & PARENB) {
406 lcr_h |= UART01x_LCRH_PEN;
407 if (!(termios->c_cflag & PARODD))
408 lcr_h |= UART01x_LCRH_EPS;
409 }
410 if (uap->port.fifosize > 1)
411 lcr_h |= UART01x_LCRH_FEN;
412
413 spin_lock_irqsave(&uap->port.lock, flags);
414
415 /*
416 * Update the per-port timeout.
417 */
418 uart_update_timeout(port, termios->c_cflag, baud);
419
420 uap->port.read_status_mask = UART01x_RSR_OE;
421 if (termios->c_iflag & INPCK)
422 uap->port.read_status_mask |= UART01x_RSR_FE | UART01x_RSR_PE;
423 if (termios->c_iflag & (BRKINT | PARMRK))
424 uap->port.read_status_mask |= UART01x_RSR_BE;
425
426 /*
427 * Characters to ignore
428 */
429 uap->port.ignore_status_mask = 0;
430 if (termios->c_iflag & IGNPAR)
431 uap->port.ignore_status_mask |= UART01x_RSR_FE | UART01x_RSR_PE;
432 if (termios->c_iflag & IGNBRK) {
433 uap->port.ignore_status_mask |= UART01x_RSR_BE;
434 /*
435 * If we're ignoring parity and break indicators,
436 * ignore overruns too (for real raw support).
437 */
438 if (termios->c_iflag & IGNPAR)
439 uap->port.ignore_status_mask |= UART01x_RSR_OE;
440 }
441
442 /*
443 * Ignore all characters if CREAD is not set.
444 */
445 if ((termios->c_cflag & CREAD) == 0)
446 uap->port.ignore_status_mask |= UART_DUMMY_RSR_RX;
447
448 /* first, disable everything */
449 old_cr = readb(uap->port.membase + UART010_CR) & ~UART010_CR_MSIE;
450
451 if (UART_ENABLE_MS(port, termios->c_cflag))
452 old_cr |= UART010_CR_MSIE;
453
454 writel(0, uap->port.membase + UART010_CR);
455
456 /* Set baud rate */
457 quot -= 1;
458 writel((quot & 0xf00) >> 8, uap->port.membase + UART010_LCRM);
459 writel(quot & 0xff, uap->port.membase + UART010_LCRL);
460
461 /*
462 * ----------v----------v----------v----------v-----
463 * NOTE: MUST BE WRITTEN AFTER UARTLCR_M & UARTLCR_L
464 * ----------^----------^----------^----------^-----
465 */
466 writel(lcr_h, uap->port.membase + UART010_LCRH);
467 writel(old_cr, uap->port.membase + UART010_CR);
468
469 spin_unlock_irqrestore(&uap->port.lock, flags);
470}
471
472static void pl010_set_ldisc(struct uart_port *port, int new)
473{
474 if (new == N_PPS) {
475 port->flags |= UPF_HARDPPS_CD;
476 pl010_enable_ms(port);
477 } else
478 port->flags &= ~UPF_HARDPPS_CD;
479}
480
481static const char *pl010_type(struct uart_port *port)
482{
483 return port->type == PORT_AMBA ? "AMBA" : NULL;
484}
485
486/*
487 * Release the memory region(s) being used by 'port'
488 */
489static void pl010_release_port(struct uart_port *port)
490{
491 release_mem_region(port->mapbase, UART_PORT_SIZE);
492}
493
494/*
495 * Request the memory region(s) being used by 'port'
496 */
497static int pl010_request_port(struct uart_port *port)
498{
499 return request_mem_region(port->mapbase, UART_PORT_SIZE, "uart-pl010")
500 != NULL ? 0 : -EBUSY;
501}
502
503/*
504 * Configure/autoconfigure the port.
505 */
506static void pl010_config_port(struct uart_port *port, int flags)
507{
508 if (flags & UART_CONFIG_TYPE) {
509 port->type = PORT_AMBA;
510 pl010_request_port(port);
511 }
512}
513
514/*
515 * verify the new serial_struct (for TIOCSSERIAL).
516 */
517static int pl010_verify_port(struct uart_port *port, struct serial_struct *ser)
518{
519 int ret = 0;
520 if (ser->type != PORT_UNKNOWN && ser->type != PORT_AMBA)
521 ret = -EINVAL;
522 if (ser->irq < 0 || ser->irq >= nr_irqs)
523 ret = -EINVAL;
524 if (ser->baud_base < 9600)
525 ret = -EINVAL;
526 return ret;
527}
528
529static struct uart_ops amba_pl010_pops = {
530 .tx_empty = pl010_tx_empty,
531 .set_mctrl = pl010_set_mctrl,
532 .get_mctrl = pl010_get_mctrl,
533 .stop_tx = pl010_stop_tx,
534 .start_tx = pl010_start_tx,
535 .stop_rx = pl010_stop_rx,
536 .enable_ms = pl010_enable_ms,
537 .break_ctl = pl010_break_ctl,
538 .startup = pl010_startup,
539 .shutdown = pl010_shutdown,
540 .set_termios = pl010_set_termios,
541 .set_ldisc = pl010_set_ldisc,
542 .type = pl010_type,
543 .release_port = pl010_release_port,
544 .request_port = pl010_request_port,
545 .config_port = pl010_config_port,
546 .verify_port = pl010_verify_port,
547};
548
549static struct uart_amba_port *amba_ports[UART_NR];
550
551#ifdef CONFIG_SERIAL_AMBA_PL010_CONSOLE
552
553static void pl010_console_putchar(struct uart_port *port, int ch)
554{
555 struct uart_amba_port *uap = (struct uart_amba_port *)port;
556 unsigned int status;
557
558 do {
559 status = readb(uap->port.membase + UART01x_FR);
560 barrier();
561 } while (!UART_TX_READY(status));
562 writel(ch, uap->port.membase + UART01x_DR);
563}
564
565static void
566pl010_console_write(struct console *co, const char *s, unsigned int count)
567{
568 struct uart_amba_port *uap = amba_ports[co->index];
569 unsigned int status, old_cr;
570
571 clk_enable(uap->clk);
572
573 /*
574 * First save the CR then disable the interrupts
575 */
576 old_cr = readb(uap->port.membase + UART010_CR);
577 writel(UART01x_CR_UARTEN, uap->port.membase + UART010_CR);
578
579 uart_console_write(&uap->port, s, count, pl010_console_putchar);
580
581 /*
582 * Finally, wait for transmitter to become empty
583 * and restore the TCR
584 */
585 do {
586 status = readb(uap->port.membase + UART01x_FR);
587 barrier();
588 } while (status & UART01x_FR_BUSY);
589 writel(old_cr, uap->port.membase + UART010_CR);
590
591 clk_disable(uap->clk);
592}
593
594static void __init
595pl010_console_get_options(struct uart_amba_port *uap, int *baud,
596 int *parity, int *bits)
597{
598 if (readb(uap->port.membase + UART010_CR) & UART01x_CR_UARTEN) {
599 unsigned int lcr_h, quot;
600 lcr_h = readb(uap->port.membase + UART010_LCRH);
601
602 *parity = 'n';
603 if (lcr_h & UART01x_LCRH_PEN) {
604 if (lcr_h & UART01x_LCRH_EPS)
605 *parity = 'e';
606 else
607 *parity = 'o';
608 }
609
610 if ((lcr_h & 0x60) == UART01x_LCRH_WLEN_7)
611 *bits = 7;
612 else
613 *bits = 8;
614
615 quot = readb(uap->port.membase + UART010_LCRL) |
616 readb(uap->port.membase + UART010_LCRM) << 8;
617 *baud = uap->port.uartclk / (16 * (quot + 1));
618 }
619}
620
621static int __init pl010_console_setup(struct console *co, char *options)
622{
623 struct uart_amba_port *uap;
624 int baud = 38400;
625 int bits = 8;
626 int parity = 'n';
627 int flow = 'n';
628 int ret;
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 ret = clk_prepare(uap->clk);
642 if (ret)
643 return ret;
644
645 uap->port.uartclk = clk_get_rate(uap->clk);
646
647 if (options)
648 uart_parse_options(options, &baud, &parity, &bits, &flow);
649 else
650 pl010_console_get_options(uap, &baud, &parity, &bits);
651
652 return uart_set_options(&uap->port, co, baud, parity, bits, flow);
653}
654
655static struct uart_driver amba_reg;
656static struct console amba_console = {
657 .name = "ttyAM",
658 .write = pl010_console_write,
659 .device = uart_console_device,
660 .setup = pl010_console_setup,
661 .flags = CON_PRINTBUFFER,
662 .index = -1,
663 .data = &amba_reg,
664};
665
666#define AMBA_CONSOLE &amba_console
667#else
668#define AMBA_CONSOLE NULL
669#endif
670
671static struct uart_driver amba_reg = {
672 .owner = THIS_MODULE,
673 .driver_name = "ttyAM",
674 .dev_name = "ttyAM",
675 .major = SERIAL_AMBA_MAJOR,
676 .minor = SERIAL_AMBA_MINOR,
677 .nr = UART_NR,
678 .cons = AMBA_CONSOLE,
679};
680
681static int pl010_probe(struct amba_device *dev, const struct amba_id *id)
682{
683 struct uart_amba_port *uap;
684 void __iomem *base;
685 int i, ret;
686
687 for (i = 0; i < ARRAY_SIZE(amba_ports); i++)
688 if (amba_ports[i] == NULL)
689 break;
690
691 if (i == ARRAY_SIZE(amba_ports)) {
692 ret = -EBUSY;
693 goto out;
694 }
695
696 uap = kzalloc(sizeof(struct uart_amba_port), GFP_KERNEL);
697 if (!uap) {
698 ret = -ENOMEM;
699 goto out;
700 }
701
702 base = ioremap(dev->res.start, resource_size(&dev->res));
703 if (!base) {
704 ret = -ENOMEM;
705 goto free;
706 }
707
708 uap->clk = clk_get(&dev->dev, NULL);
709 if (IS_ERR(uap->clk)) {
710 ret = PTR_ERR(uap->clk);
711 goto unmap;
712 }
713
714 uap->port.dev = &dev->dev;
715 uap->port.mapbase = dev->res.start;
716 uap->port.membase = base;
717 uap->port.iotype = UPIO_MEM;
718 uap->port.irq = dev->irq[0];
719 uap->port.fifosize = 16;
720 uap->port.ops = &amba_pl010_pops;
721 uap->port.flags = UPF_BOOT_AUTOCONF;
722 uap->port.line = i;
723 uap->dev = dev;
724 uap->data = dev_get_platdata(&dev->dev);
725
726 amba_ports[i] = uap;
727
728 amba_set_drvdata(dev, uap);
729 ret = uart_add_one_port(&amba_reg, &uap->port);
730 if (ret) {
731 amba_ports[i] = NULL;
732 clk_put(uap->clk);
733 unmap:
734 iounmap(base);
735 free:
736 kfree(uap);
737 }
738 out:
739 return ret;
740}
741
742static int pl010_remove(struct amba_device *dev)
743{
744 struct uart_amba_port *uap = amba_get_drvdata(dev);
745 int i;
746
747 uart_remove_one_port(&amba_reg, &uap->port);
748
749 for (i = 0; i < ARRAY_SIZE(amba_ports); i++)
750 if (amba_ports[i] == uap)
751 amba_ports[i] = NULL;
752
753 iounmap(uap->port.membase);
754 clk_put(uap->clk);
755 kfree(uap);
756 return 0;
757}
758
759#ifdef CONFIG_PM_SLEEP
760static int pl010_suspend(struct device *dev)
761{
762 struct uart_amba_port *uap = dev_get_drvdata(dev);
763
764 if (uap)
765 uart_suspend_port(&amba_reg, &uap->port);
766
767 return 0;
768}
769
770static int pl010_resume(struct device *dev)
771{
772 struct uart_amba_port *uap = dev_get_drvdata(dev);
773
774 if (uap)
775 uart_resume_port(&amba_reg, &uap->port);
776
777 return 0;
778}
779#endif
780
781static SIMPLE_DEV_PM_OPS(pl010_dev_pm_ops, pl010_suspend, pl010_resume);
782
783static struct amba_id pl010_ids[] = {
784 {
785 .id = 0x00041010,
786 .mask = 0x000fffff,
787 },
788 { 0, 0 },
789};
790
791MODULE_DEVICE_TABLE(amba, pl010_ids);
792
793static struct amba_driver pl010_driver = {
794 .drv = {
795 .name = "uart-pl010",
796 .pm = &pl010_dev_pm_ops,
797 },
798 .id_table = pl010_ids,
799 .probe = pl010_probe,
800 .remove = pl010_remove,
801};
802
803static int __init pl010_init(void)
804{
805 int ret;
806
807 printk(KERN_INFO "Serial: AMBA driver\n");
808
809 ret = uart_register_driver(&amba_reg);
810 if (ret == 0) {
811 ret = amba_driver_register(&pl010_driver);
812 if (ret)
813 uart_unregister_driver(&amba_reg);
814 }
815 return ret;
816}
817
818static void __exit pl010_exit(void)
819{
820 amba_driver_unregister(&pl010_driver);
821 uart_unregister_driver(&amba_reg);
822}
823
824module_init(pl010_init);
825module_exit(pl010_exit);
826
827MODULE_AUTHOR("ARM Ltd/Deep Blue Solutions Ltd");
828MODULE_DESCRIPTION("ARM AMBA serial port driver");
829MODULE_LICENSE("GPL");