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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#include <linux/module.h>
19#include <linux/ioport.h>
20#include <linux/init.h>
21#include <linux/console.h>
22#include <linux/sysrq.h>
23#include <linux/device.h>
24#include <linux/tty.h>
25#include <linux/tty_flip.h>
26#include <linux/serial_core.h>
27#include <linux/serial.h>
28#include <linux/amba/bus.h>
29#include <linux/amba/serial.h>
30#include <linux/clk.h>
31#include <linux/slab.h>
32#include <linux/io.h>
33
34#define UART_NR 8
35
36#define SERIAL_AMBA_MAJOR 204
37#define SERIAL_AMBA_MINOR 16
38#define SERIAL_AMBA_NR UART_NR
39
40#define AMBA_ISR_PASS_LIMIT 256
41
42#define UART_RX_DATA(s) (((s) & UART01x_FR_RXFE) == 0)
43#define UART_TX_READY(s) (((s) & UART01x_FR_TXFF) == 0)
44
45#define UART_DUMMY_RSR_RX 256
46#define UART_PORT_SIZE 64
47
48/*
49 * We wrap our port structure around the generic uart_port.
50 */
51struct uart_amba_port {
52 struct uart_port port;
53 struct clk *clk;
54 struct amba_device *dev;
55 struct amba_pl010_data *data;
56 unsigned int old_status;
57};
58
59static void pl010_stop_tx(struct uart_port *port)
60{
61 struct uart_amba_port *uap =
62 container_of(port, struct uart_amba_port, port);
63 unsigned int cr;
64
65 cr = readb(uap->port.membase + UART010_CR);
66 cr &= ~UART010_CR_TIE;
67 writel(cr, uap->port.membase + UART010_CR);
68}
69
70static void pl010_start_tx(struct uart_port *port)
71{
72 struct uart_amba_port *uap =
73 container_of(port, struct uart_amba_port, port);
74 unsigned int cr;
75
76 cr = readb(uap->port.membase + UART010_CR);
77 cr |= UART010_CR_TIE;
78 writel(cr, uap->port.membase + UART010_CR);
79}
80
81static void pl010_stop_rx(struct uart_port *port)
82{
83 struct uart_amba_port *uap =
84 container_of(port, struct uart_amba_port, port);
85 unsigned int cr;
86
87 cr = readb(uap->port.membase + UART010_CR);
88 cr &= ~(UART010_CR_RIE | UART010_CR_RTIE);
89 writel(cr, uap->port.membase + UART010_CR);
90}
91
92static void pl010_disable_ms(struct uart_port *port)
93{
94 struct uart_amba_port *uap = (struct uart_amba_port *)port;
95 unsigned int cr;
96
97 cr = readb(uap->port.membase + UART010_CR);
98 cr &= ~UART010_CR_MSIE;
99 writel(cr, uap->port.membase + UART010_CR);
100}
101
102static void pl010_enable_ms(struct uart_port *port)
103{
104 struct uart_amba_port *uap =
105 container_of(port, struct uart_amba_port, port);
106 unsigned int cr;
107
108 cr = readb(uap->port.membase + UART010_CR);
109 cr |= UART010_CR_MSIE;
110 writel(cr, uap->port.membase + UART010_CR);
111}
112
113static void pl010_rx_chars(struct uart_port *port)
114{
115 unsigned int status, ch, flag, rsr, max_count = 256;
116
117 status = readb(port->membase + UART01x_FR);
118 while (UART_RX_DATA(status) && max_count--) {
119 ch = readb(port->membase + UART01x_DR);
120 flag = TTY_NORMAL;
121
122 port->icount.rx++;
123
124 /*
125 * Note that the error handling code is
126 * out of the main execution path
127 */
128 rsr = readb(port->membase + UART01x_RSR) | UART_DUMMY_RSR_RX;
129 if (unlikely(rsr & UART01x_RSR_ANY)) {
130 writel(0, port->membase + UART01x_ECR);
131
132 if (rsr & UART01x_RSR_BE) {
133 rsr &= ~(UART01x_RSR_FE | UART01x_RSR_PE);
134 port->icount.brk++;
135 if (uart_handle_break(port))
136 goto ignore_char;
137 } else if (rsr & UART01x_RSR_PE)
138 port->icount.parity++;
139 else if (rsr & UART01x_RSR_FE)
140 port->icount.frame++;
141 if (rsr & UART01x_RSR_OE)
142 port->icount.overrun++;
143
144 rsr &= port->read_status_mask;
145
146 if (rsr & UART01x_RSR_BE)
147 flag = TTY_BREAK;
148 else if (rsr & UART01x_RSR_PE)
149 flag = TTY_PARITY;
150 else if (rsr & UART01x_RSR_FE)
151 flag = TTY_FRAME;
152 }
153
154 if (uart_handle_sysrq_char(port, ch))
155 goto ignore_char;
156
157 uart_insert_char(port, rsr, UART01x_RSR_OE, ch, flag);
158
159 ignore_char:
160 status = readb(port->membase + UART01x_FR);
161 }
162 tty_flip_buffer_push(&port->state->port);
163}
164
165static void pl010_tx_chars(struct uart_port *port)
166{
167 u8 ch;
168
169 uart_port_tx_limited(port, ch, port->fifosize >> 1,
170 true,
171 writel(ch, port->membase + UART01x_DR),
172 ({}));
173}
174
175static void pl010_modem_status(struct uart_amba_port *uap)
176{
177 struct uart_port *port = &uap->port;
178 unsigned int status, delta;
179
180 writel(0, port->membase + UART010_ICR);
181
182 status = readb(port->membase + UART01x_FR) & UART01x_FR_MODEM_ANY;
183
184 delta = status ^ uap->old_status;
185 uap->old_status = status;
186
187 if (!delta)
188 return;
189
190 if (delta & UART01x_FR_DCD)
191 uart_handle_dcd_change(port, status & UART01x_FR_DCD);
192
193 if (delta & UART01x_FR_DSR)
194 port->icount.dsr++;
195
196 if (delta & UART01x_FR_CTS)
197 uart_handle_cts_change(port, status & UART01x_FR_CTS);
198
199 wake_up_interruptible(&port->state->port.delta_msr_wait);
200}
201
202static irqreturn_t pl010_int(int irq, void *dev_id)
203{
204 struct uart_amba_port *uap = dev_id;
205 struct uart_port *port = &uap->port;
206 unsigned int status, pass_counter = AMBA_ISR_PASS_LIMIT;
207 int handled = 0;
208
209 spin_lock(&port->lock);
210
211 status = readb(port->membase + UART010_IIR);
212 if (status) {
213 do {
214 if (status & (UART010_IIR_RTIS | UART010_IIR_RIS))
215 pl010_rx_chars(port);
216 if (status & UART010_IIR_MIS)
217 pl010_modem_status(uap);
218 if (status & UART010_IIR_TIS)
219 pl010_tx_chars(port);
220
221 if (pass_counter-- == 0)
222 break;
223
224 status = readb(port->membase + UART010_IIR);
225 } while (status & (UART010_IIR_RTIS | UART010_IIR_RIS |
226 UART010_IIR_TIS));
227 handled = 1;
228 }
229
230 spin_unlock(&port->lock);
231
232 return IRQ_RETVAL(handled);
233}
234
235static unsigned int pl010_tx_empty(struct uart_port *port)
236{
237 unsigned int status = readb(port->membase + UART01x_FR);
238
239 return status & UART01x_FR_BUSY ? 0 : TIOCSER_TEMT;
240}
241
242static unsigned int pl010_get_mctrl(struct uart_port *port)
243{
244 unsigned int result = 0;
245 unsigned int status;
246
247 status = readb(port->membase + UART01x_FR);
248 if (status & UART01x_FR_DCD)
249 result |= TIOCM_CAR;
250 if (status & UART01x_FR_DSR)
251 result |= TIOCM_DSR;
252 if (status & UART01x_FR_CTS)
253 result |= TIOCM_CTS;
254
255 return result;
256}
257
258static void pl010_set_mctrl(struct uart_port *port, unsigned int mctrl)
259{
260 struct uart_amba_port *uap =
261 container_of(port, struct uart_amba_port, port);
262
263 if (uap->data)
264 uap->data->set_mctrl(uap->dev, port->membase, mctrl);
265}
266
267static void pl010_break_ctl(struct uart_port *port, int break_state)
268{
269 unsigned long flags;
270 unsigned int lcr_h;
271
272 spin_lock_irqsave(&port->lock, flags);
273 lcr_h = readb(port->membase + UART010_LCRH);
274 if (break_state == -1)
275 lcr_h |= UART01x_LCRH_BRK;
276 else
277 lcr_h &= ~UART01x_LCRH_BRK;
278 writel(lcr_h, port->membase + UART010_LCRH);
279 spin_unlock_irqrestore(&port->lock, flags);
280}
281
282static int pl010_startup(struct uart_port *port)
283{
284 struct uart_amba_port *uap =
285 container_of(port, struct uart_amba_port, port);
286 int retval;
287
288 /*
289 * Try to enable the clock producer.
290 */
291 retval = clk_prepare_enable(uap->clk);
292 if (retval)
293 goto out;
294
295 port->uartclk = clk_get_rate(uap->clk);
296
297 /*
298 * Allocate the IRQ
299 */
300 retval = request_irq(port->irq, pl010_int, 0, "uart-pl010", uap);
301 if (retval)
302 goto clk_dis;
303
304 /*
305 * initialise the old status of the modem signals
306 */
307 uap->old_status = readb(port->membase + UART01x_FR) & UART01x_FR_MODEM_ANY;
308
309 /*
310 * Finally, enable interrupts
311 */
312 writel(UART01x_CR_UARTEN | UART010_CR_RIE | UART010_CR_RTIE,
313 port->membase + UART010_CR);
314
315 return 0;
316
317 clk_dis:
318 clk_disable_unprepare(uap->clk);
319 out:
320 return retval;
321}
322
323static void pl010_shutdown(struct uart_port *port)
324{
325 struct uart_amba_port *uap =
326 container_of(port, struct uart_amba_port, port);
327
328 /*
329 * Free the interrupt
330 */
331 free_irq(port->irq, uap);
332
333 /*
334 * disable all interrupts, disable the port
335 */
336 writel(0, port->membase + UART010_CR);
337
338 /* disable break condition and fifos */
339 writel(readb(port->membase + UART010_LCRH) &
340 ~(UART01x_LCRH_BRK | UART01x_LCRH_FEN),
341 port->membase + UART010_LCRH);
342
343 /*
344 * Shut down the clock producer
345 */
346 clk_disable_unprepare(uap->clk);
347}
348
349static void
350pl010_set_termios(struct uart_port *port, struct ktermios *termios,
351 const struct ktermios *old)
352{
353 unsigned int lcr_h, old_cr;
354 unsigned long flags;
355 unsigned int baud, quot;
356
357 /*
358 * Ask the core to calculate the divisor for us.
359 */
360 baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk / 16);
361 quot = uart_get_divisor(port, baud);
362
363 switch (termios->c_cflag & CSIZE) {
364 case CS5:
365 lcr_h = UART01x_LCRH_WLEN_5;
366 break;
367 case CS6:
368 lcr_h = UART01x_LCRH_WLEN_6;
369 break;
370 case CS7:
371 lcr_h = UART01x_LCRH_WLEN_7;
372 break;
373 default: // CS8
374 lcr_h = UART01x_LCRH_WLEN_8;
375 break;
376 }
377 if (termios->c_cflag & CSTOPB)
378 lcr_h |= UART01x_LCRH_STP2;
379 if (termios->c_cflag & PARENB) {
380 lcr_h |= UART01x_LCRH_PEN;
381 if (!(termios->c_cflag & PARODD))
382 lcr_h |= UART01x_LCRH_EPS;
383 }
384 if (port->fifosize > 1)
385 lcr_h |= UART01x_LCRH_FEN;
386
387 spin_lock_irqsave(&port->lock, flags);
388
389 /*
390 * Update the per-port timeout.
391 */
392 uart_update_timeout(port, termios->c_cflag, baud);
393
394 port->read_status_mask = UART01x_RSR_OE;
395 if (termios->c_iflag & INPCK)
396 port->read_status_mask |= UART01x_RSR_FE | UART01x_RSR_PE;
397 if (termios->c_iflag & (IGNBRK | BRKINT | PARMRK))
398 port->read_status_mask |= UART01x_RSR_BE;
399
400 /*
401 * Characters to ignore
402 */
403 port->ignore_status_mask = 0;
404 if (termios->c_iflag & IGNPAR)
405 port->ignore_status_mask |= UART01x_RSR_FE | UART01x_RSR_PE;
406 if (termios->c_iflag & IGNBRK) {
407 port->ignore_status_mask |= UART01x_RSR_BE;
408 /*
409 * If we're ignoring parity and break indicators,
410 * ignore overruns too (for real raw support).
411 */
412 if (termios->c_iflag & IGNPAR)
413 port->ignore_status_mask |= UART01x_RSR_OE;
414 }
415
416 /*
417 * Ignore all characters if CREAD is not set.
418 */
419 if ((termios->c_cflag & CREAD) == 0)
420 port->ignore_status_mask |= UART_DUMMY_RSR_RX;
421
422 old_cr = readb(port->membase + UART010_CR) & ~UART010_CR_MSIE;
423
424 if (UART_ENABLE_MS(port, termios->c_cflag))
425 old_cr |= UART010_CR_MSIE;
426
427 /* Set baud rate */
428 quot -= 1;
429 writel((quot & 0xf00) >> 8, port->membase + UART010_LCRM);
430 writel(quot & 0xff, port->membase + UART010_LCRL);
431
432 /*
433 * ----------v----------v----------v----------v-----
434 * NOTE: MUST BE WRITTEN AFTER UARTLCR_M & UARTLCR_L
435 * ----------^----------^----------^----------^-----
436 */
437 writel(lcr_h, port->membase + UART010_LCRH);
438 writel(old_cr, port->membase + UART010_CR);
439
440 spin_unlock_irqrestore(&port->lock, flags);
441}
442
443static void pl010_set_ldisc(struct uart_port *port, struct ktermios *termios)
444{
445 if (termios->c_line == N_PPS) {
446 port->flags |= UPF_HARDPPS_CD;
447 spin_lock_irq(&port->lock);
448 pl010_enable_ms(port);
449 spin_unlock_irq(&port->lock);
450 } else {
451 port->flags &= ~UPF_HARDPPS_CD;
452 if (!UART_ENABLE_MS(port, termios->c_cflag)) {
453 spin_lock_irq(&port->lock);
454 pl010_disable_ms(port);
455 spin_unlock_irq(&port->lock);
456 }
457 }
458}
459
460static const char *pl010_type(struct uart_port *port)
461{
462 return port->type == PORT_AMBA ? "AMBA" : NULL;
463}
464
465/*
466 * Release the memory region(s) being used by 'port'
467 */
468static void pl010_release_port(struct uart_port *port)
469{
470 release_mem_region(port->mapbase, UART_PORT_SIZE);
471}
472
473/*
474 * Request the memory region(s) being used by 'port'
475 */
476static int pl010_request_port(struct uart_port *port)
477{
478 return request_mem_region(port->mapbase, UART_PORT_SIZE, "uart-pl010")
479 != NULL ? 0 : -EBUSY;
480}
481
482/*
483 * Configure/autoconfigure the port.
484 */
485static void pl010_config_port(struct uart_port *port, int flags)
486{
487 if (flags & UART_CONFIG_TYPE) {
488 port->type = PORT_AMBA;
489 pl010_request_port(port);
490 }
491}
492
493/*
494 * verify the new serial_struct (for TIOCSSERIAL).
495 */
496static int pl010_verify_port(struct uart_port *port, struct serial_struct *ser)
497{
498 int ret = 0;
499 if (ser->type != PORT_UNKNOWN && ser->type != PORT_AMBA)
500 ret = -EINVAL;
501 if (ser->irq < 0 || ser->irq >= nr_irqs)
502 ret = -EINVAL;
503 if (ser->baud_base < 9600)
504 ret = -EINVAL;
505 return ret;
506}
507
508static const struct uart_ops amba_pl010_pops = {
509 .tx_empty = pl010_tx_empty,
510 .set_mctrl = pl010_set_mctrl,
511 .get_mctrl = pl010_get_mctrl,
512 .stop_tx = pl010_stop_tx,
513 .start_tx = pl010_start_tx,
514 .stop_rx = pl010_stop_rx,
515 .enable_ms = pl010_enable_ms,
516 .break_ctl = pl010_break_ctl,
517 .startup = pl010_startup,
518 .shutdown = pl010_shutdown,
519 .set_termios = pl010_set_termios,
520 .set_ldisc = pl010_set_ldisc,
521 .type = pl010_type,
522 .release_port = pl010_release_port,
523 .request_port = pl010_request_port,
524 .config_port = pl010_config_port,
525 .verify_port = pl010_verify_port,
526};
527
528static struct uart_amba_port *amba_ports[UART_NR];
529
530#ifdef CONFIG_SERIAL_AMBA_PL010_CONSOLE
531
532static void pl010_console_putchar(struct uart_port *port, unsigned char ch)
533{
534 unsigned int status;
535
536 do {
537 status = readb(port->membase + UART01x_FR);
538 barrier();
539 } while (!UART_TX_READY(status));
540 writel(ch, port->membase + UART01x_DR);
541}
542
543static void
544pl010_console_write(struct console *co, const char *s, unsigned int count)
545{
546 struct uart_amba_port *uap = amba_ports[co->index];
547 struct uart_port *port = &uap->port;
548 unsigned int status, old_cr;
549
550 clk_enable(uap->clk);
551
552 /*
553 * First save the CR then disable the interrupts
554 */
555 old_cr = readb(port->membase + UART010_CR);
556 writel(UART01x_CR_UARTEN, port->membase + UART010_CR);
557
558 uart_console_write(port, s, count, pl010_console_putchar);
559
560 /*
561 * Finally, wait for transmitter to become empty
562 * and restore the TCR
563 */
564 do {
565 status = readb(port->membase + UART01x_FR);
566 barrier();
567 } while (status & UART01x_FR_BUSY);
568 writel(old_cr, port->membase + UART010_CR);
569
570 clk_disable(uap->clk);
571}
572
573static void __init
574pl010_console_get_options(struct uart_amba_port *uap, int *baud,
575 int *parity, int *bits)
576{
577 if (readb(uap->port.membase + UART010_CR) & UART01x_CR_UARTEN) {
578 unsigned int lcr_h, quot;
579 lcr_h = readb(uap->port.membase + UART010_LCRH);
580
581 *parity = 'n';
582 if (lcr_h & UART01x_LCRH_PEN) {
583 if (lcr_h & UART01x_LCRH_EPS)
584 *parity = 'e';
585 else
586 *parity = 'o';
587 }
588
589 if ((lcr_h & 0x60) == UART01x_LCRH_WLEN_7)
590 *bits = 7;
591 else
592 *bits = 8;
593
594 quot = readb(uap->port.membase + UART010_LCRL) |
595 readb(uap->port.membase + UART010_LCRM) << 8;
596 *baud = uap->port.uartclk / (16 * (quot + 1));
597 }
598}
599
600static int __init pl010_console_setup(struct console *co, char *options)
601{
602 struct uart_amba_port *uap;
603 int baud = 38400;
604 int bits = 8;
605 int parity = 'n';
606 int flow = 'n';
607 int ret;
608
609 /*
610 * Check whether an invalid uart number has been specified, and
611 * if so, search for the first available port that does have
612 * console support.
613 */
614 if (co->index >= UART_NR)
615 co->index = 0;
616 uap = amba_ports[co->index];
617 if (!uap)
618 return -ENODEV;
619
620 ret = clk_prepare(uap->clk);
621 if (ret)
622 return ret;
623
624 uap->port.uartclk = clk_get_rate(uap->clk);
625
626 if (options)
627 uart_parse_options(options, &baud, &parity, &bits, &flow);
628 else
629 pl010_console_get_options(uap, &baud, &parity, &bits);
630
631 return uart_set_options(&uap->port, co, baud, parity, bits, flow);
632}
633
634static struct uart_driver amba_reg;
635static struct console amba_console = {
636 .name = "ttyAM",
637 .write = pl010_console_write,
638 .device = uart_console_device,
639 .setup = pl010_console_setup,
640 .flags = CON_PRINTBUFFER,
641 .index = -1,
642 .data = &amba_reg,
643};
644
645#define AMBA_CONSOLE &amba_console
646#else
647#define AMBA_CONSOLE NULL
648#endif
649
650static DEFINE_MUTEX(amba_reg_lock);
651static struct uart_driver amba_reg = {
652 .owner = THIS_MODULE,
653 .driver_name = "ttyAM",
654 .dev_name = "ttyAM",
655 .major = SERIAL_AMBA_MAJOR,
656 .minor = SERIAL_AMBA_MINOR,
657 .nr = UART_NR,
658 .cons = AMBA_CONSOLE,
659};
660
661static int pl010_probe(struct amba_device *dev, const struct amba_id *id)
662{
663 struct uart_amba_port *uap;
664 void __iomem *base;
665 int i, ret;
666
667 for (i = 0; i < ARRAY_SIZE(amba_ports); i++)
668 if (amba_ports[i] == NULL)
669 break;
670
671 if (i == ARRAY_SIZE(amba_ports))
672 return -EBUSY;
673
674 uap = devm_kzalloc(&dev->dev, sizeof(struct uart_amba_port),
675 GFP_KERNEL);
676 if (!uap)
677 return -ENOMEM;
678
679 base = devm_ioremap(&dev->dev, dev->res.start,
680 resource_size(&dev->res));
681 if (!base)
682 return -ENOMEM;
683
684 uap->clk = devm_clk_get(&dev->dev, NULL);
685 if (IS_ERR(uap->clk))
686 return PTR_ERR(uap->clk);
687
688 uap->port.dev = &dev->dev;
689 uap->port.mapbase = dev->res.start;
690 uap->port.membase = base;
691 uap->port.iotype = UPIO_MEM;
692 uap->port.irq = dev->irq[0];
693 uap->port.fifosize = 16;
694 uap->port.has_sysrq = IS_ENABLED(CONFIG_SERIAL_AMBA_PL010_CONSOLE);
695 uap->port.ops = &amba_pl010_pops;
696 uap->port.flags = UPF_BOOT_AUTOCONF;
697 uap->port.line = i;
698 uap->dev = dev;
699 uap->data = dev_get_platdata(&dev->dev);
700
701 amba_ports[i] = uap;
702
703 amba_set_drvdata(dev, uap);
704
705 mutex_lock(&amba_reg_lock);
706 if (!amba_reg.state) {
707 ret = uart_register_driver(&amba_reg);
708 if (ret < 0) {
709 mutex_unlock(&amba_reg_lock);
710 dev_err(uap->port.dev,
711 "Failed to register AMBA-PL010 driver\n");
712 return ret;
713 }
714 }
715 mutex_unlock(&amba_reg_lock);
716
717 ret = uart_add_one_port(&amba_reg, &uap->port);
718 if (ret)
719 amba_ports[i] = NULL;
720
721 return ret;
722}
723
724static void pl010_remove(struct amba_device *dev)
725{
726 struct uart_amba_port *uap = amba_get_drvdata(dev);
727 int i;
728 bool busy = false;
729
730 uart_remove_one_port(&amba_reg, &uap->port);
731
732 for (i = 0; i < ARRAY_SIZE(amba_ports); i++)
733 if (amba_ports[i] == uap)
734 amba_ports[i] = NULL;
735 else if (amba_ports[i])
736 busy = true;
737
738 if (!busy)
739 uart_unregister_driver(&amba_reg);
740}
741
742#ifdef CONFIG_PM_SLEEP
743static int pl010_suspend(struct device *dev)
744{
745 struct uart_amba_port *uap = dev_get_drvdata(dev);
746
747 if (uap)
748 uart_suspend_port(&amba_reg, &uap->port);
749
750 return 0;
751}
752
753static int pl010_resume(struct device *dev)
754{
755 struct uart_amba_port *uap = dev_get_drvdata(dev);
756
757 if (uap)
758 uart_resume_port(&amba_reg, &uap->port);
759
760 return 0;
761}
762#endif
763
764static SIMPLE_DEV_PM_OPS(pl010_dev_pm_ops, pl010_suspend, pl010_resume);
765
766static const struct amba_id pl010_ids[] = {
767 {
768 .id = 0x00041010,
769 .mask = 0x000fffff,
770 },
771 { 0, 0 },
772};
773
774MODULE_DEVICE_TABLE(amba, pl010_ids);
775
776static struct amba_driver pl010_driver = {
777 .drv = {
778 .name = "uart-pl010",
779 .pm = &pl010_dev_pm_ops,
780 },
781 .id_table = pl010_ids,
782 .probe = pl010_probe,
783 .remove = pl010_remove,
784};
785
786static int __init pl010_init(void)
787{
788 printk(KERN_INFO "Serial: AMBA driver\n");
789
790 return amba_driver_register(&pl010_driver);
791}
792
793static void __exit pl010_exit(void)
794{
795 amba_driver_unregister(&pl010_driver);
796}
797
798module_init(pl010_init);
799module_exit(pl010_exit);
800
801MODULE_AUTHOR("ARM Ltd/Deep Blue Solutions Ltd");
802MODULE_DESCRIPTION("ARM AMBA serial port driver");
803MODULE_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 retval = clk_prepare(uap->clk);
316 if (retval)
317 goto out;
318
319 /*
320 * Try to enable the clock producer.
321 */
322 retval = clk_enable(uap->clk);
323 if (retval)
324 goto clk_unprep;
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(uap->clk);
350 clk_unprep:
351 clk_unprepare(uap->clk);
352 out:
353 return retval;
354}
355
356static void pl010_shutdown(struct uart_port *port)
357{
358 struct uart_amba_port *uap = (struct uart_amba_port *)port;
359
360 /*
361 * Free the interrupt
362 */
363 free_irq(uap->port.irq, uap);
364
365 /*
366 * disable all interrupts, disable the port
367 */
368 writel(0, uap->port.membase + UART010_CR);
369
370 /* disable break condition and fifos */
371 writel(readb(uap->port.membase + UART010_LCRH) &
372 ~(UART01x_LCRH_BRK | UART01x_LCRH_FEN),
373 uap->port.membase + UART010_LCRH);
374
375 /*
376 * Shut down the clock producer
377 */
378 clk_disable(uap->clk);
379 clk_unprepare(uap->clk);
380}
381
382static void
383pl010_set_termios(struct uart_port *port, struct ktermios *termios,
384 struct ktermios *old)
385{
386 struct uart_amba_port *uap = (struct uart_amba_port *)port;
387 unsigned int lcr_h, old_cr;
388 unsigned long flags;
389 unsigned int baud, quot;
390
391 /*
392 * Ask the core to calculate the divisor for us.
393 */
394 baud = uart_get_baud_rate(port, termios, old, 0, uap->port.uartclk/16);
395 quot = uart_get_divisor(port, baud);
396
397 switch (termios->c_cflag & CSIZE) {
398 case CS5:
399 lcr_h = UART01x_LCRH_WLEN_5;
400 break;
401 case CS6:
402 lcr_h = UART01x_LCRH_WLEN_6;
403 break;
404 case CS7:
405 lcr_h = UART01x_LCRH_WLEN_7;
406 break;
407 default: // CS8
408 lcr_h = UART01x_LCRH_WLEN_8;
409 break;
410 }
411 if (termios->c_cflag & CSTOPB)
412 lcr_h |= UART01x_LCRH_STP2;
413 if (termios->c_cflag & PARENB) {
414 lcr_h |= UART01x_LCRH_PEN;
415 if (!(termios->c_cflag & PARODD))
416 lcr_h |= UART01x_LCRH_EPS;
417 }
418 if (uap->port.fifosize > 1)
419 lcr_h |= UART01x_LCRH_FEN;
420
421 spin_lock_irqsave(&uap->port.lock, flags);
422
423 /*
424 * Update the per-port timeout.
425 */
426 uart_update_timeout(port, termios->c_cflag, baud);
427
428 uap->port.read_status_mask = UART01x_RSR_OE;
429 if (termios->c_iflag & INPCK)
430 uap->port.read_status_mask |= UART01x_RSR_FE | UART01x_RSR_PE;
431 if (termios->c_iflag & (BRKINT | PARMRK))
432 uap->port.read_status_mask |= UART01x_RSR_BE;
433
434 /*
435 * Characters to ignore
436 */
437 uap->port.ignore_status_mask = 0;
438 if (termios->c_iflag & IGNPAR)
439 uap->port.ignore_status_mask |= UART01x_RSR_FE | UART01x_RSR_PE;
440 if (termios->c_iflag & IGNBRK) {
441 uap->port.ignore_status_mask |= UART01x_RSR_BE;
442 /*
443 * If we're ignoring parity and break indicators,
444 * ignore overruns too (for real raw support).
445 */
446 if (termios->c_iflag & IGNPAR)
447 uap->port.ignore_status_mask |= UART01x_RSR_OE;
448 }
449
450 /*
451 * Ignore all characters if CREAD is not set.
452 */
453 if ((termios->c_cflag & CREAD) == 0)
454 uap->port.ignore_status_mask |= UART_DUMMY_RSR_RX;
455
456 /* first, disable everything */
457 old_cr = readb(uap->port.membase + UART010_CR) & ~UART010_CR_MSIE;
458
459 if (UART_ENABLE_MS(port, termios->c_cflag))
460 old_cr |= UART010_CR_MSIE;
461
462 writel(0, uap->port.membase + UART010_CR);
463
464 /* Set baud rate */
465 quot -= 1;
466 writel((quot & 0xf00) >> 8, uap->port.membase + UART010_LCRM);
467 writel(quot & 0xff, uap->port.membase + UART010_LCRL);
468
469 /*
470 * ----------v----------v----------v----------v-----
471 * NOTE: MUST BE WRITTEN AFTER UARTLCR_M & UARTLCR_L
472 * ----------^----------^----------^----------^-----
473 */
474 writel(lcr_h, uap->port.membase + UART010_LCRH);
475 writel(old_cr, uap->port.membase + UART010_CR);
476
477 spin_unlock_irqrestore(&uap->port.lock, flags);
478}
479
480static void pl010_set_ldisc(struct uart_port *port, int new)
481{
482 if (new == N_PPS) {
483 port->flags |= UPF_HARDPPS_CD;
484 pl010_enable_ms(port);
485 } else
486 port->flags &= ~UPF_HARDPPS_CD;
487}
488
489static const char *pl010_type(struct uart_port *port)
490{
491 return port->type == PORT_AMBA ? "AMBA" : NULL;
492}
493
494/*
495 * Release the memory region(s) being used by 'port'
496 */
497static void pl010_release_port(struct uart_port *port)
498{
499 release_mem_region(port->mapbase, UART_PORT_SIZE);
500}
501
502/*
503 * Request the memory region(s) being used by 'port'
504 */
505static int pl010_request_port(struct uart_port *port)
506{
507 return request_mem_region(port->mapbase, UART_PORT_SIZE, "uart-pl010")
508 != NULL ? 0 : -EBUSY;
509}
510
511/*
512 * Configure/autoconfigure the port.
513 */
514static void pl010_config_port(struct uart_port *port, int flags)
515{
516 if (flags & UART_CONFIG_TYPE) {
517 port->type = PORT_AMBA;
518 pl010_request_port(port);
519 }
520}
521
522/*
523 * verify the new serial_struct (for TIOCSSERIAL).
524 */
525static int pl010_verify_port(struct uart_port *port, struct serial_struct *ser)
526{
527 int ret = 0;
528 if (ser->type != PORT_UNKNOWN && ser->type != PORT_AMBA)
529 ret = -EINVAL;
530 if (ser->irq < 0 || ser->irq >= nr_irqs)
531 ret = -EINVAL;
532 if (ser->baud_base < 9600)
533 ret = -EINVAL;
534 return ret;
535}
536
537static struct uart_ops amba_pl010_pops = {
538 .tx_empty = pl010_tx_empty,
539 .set_mctrl = pl010_set_mctrl,
540 .get_mctrl = pl010_get_mctrl,
541 .stop_tx = pl010_stop_tx,
542 .start_tx = pl010_start_tx,
543 .stop_rx = pl010_stop_rx,
544 .enable_ms = pl010_enable_ms,
545 .break_ctl = pl010_break_ctl,
546 .startup = pl010_startup,
547 .shutdown = pl010_shutdown,
548 .set_termios = pl010_set_termios,
549 .set_ldisc = pl010_set_ldisc,
550 .type = pl010_type,
551 .release_port = pl010_release_port,
552 .request_port = pl010_request_port,
553 .config_port = pl010_config_port,
554 .verify_port = pl010_verify_port,
555};
556
557static struct uart_amba_port *amba_ports[UART_NR];
558
559#ifdef CONFIG_SERIAL_AMBA_PL010_CONSOLE
560
561static void pl010_console_putchar(struct uart_port *port, int ch)
562{
563 struct uart_amba_port *uap = (struct uart_amba_port *)port;
564 unsigned int status;
565
566 do {
567 status = readb(uap->port.membase + UART01x_FR);
568 barrier();
569 } while (!UART_TX_READY(status));
570 writel(ch, uap->port.membase + UART01x_DR);
571}
572
573static void
574pl010_console_write(struct console *co, const char *s, unsigned int count)
575{
576 struct uart_amba_port *uap = amba_ports[co->index];
577 unsigned int status, old_cr;
578
579 clk_enable(uap->clk);
580
581 /*
582 * First save the CR then disable the interrupts
583 */
584 old_cr = readb(uap->port.membase + UART010_CR);
585 writel(UART01x_CR_UARTEN, uap->port.membase + UART010_CR);
586
587 uart_console_write(&uap->port, s, count, pl010_console_putchar);
588
589 /*
590 * Finally, wait for transmitter to become empty
591 * and restore the TCR
592 */
593 do {
594 status = readb(uap->port.membase + UART01x_FR);
595 barrier();
596 } while (status & UART01x_FR_BUSY);
597 writel(old_cr, uap->port.membase + UART010_CR);
598
599 clk_disable(uap->clk);
600}
601
602static void __init
603pl010_console_get_options(struct uart_amba_port *uap, int *baud,
604 int *parity, int *bits)
605{
606 if (readb(uap->port.membase + UART010_CR) & UART01x_CR_UARTEN) {
607 unsigned int lcr_h, quot;
608 lcr_h = readb(uap->port.membase + UART010_LCRH);
609
610 *parity = 'n';
611 if (lcr_h & UART01x_LCRH_PEN) {
612 if (lcr_h & UART01x_LCRH_EPS)
613 *parity = 'e';
614 else
615 *parity = 'o';
616 }
617
618 if ((lcr_h & 0x60) == UART01x_LCRH_WLEN_7)
619 *bits = 7;
620 else
621 *bits = 8;
622
623 quot = readb(uap->port.membase + UART010_LCRL) |
624 readb(uap->port.membase + UART010_LCRM) << 8;
625 *baud = uap->port.uartclk / (16 * (quot + 1));
626 }
627}
628
629static int __init pl010_console_setup(struct console *co, char *options)
630{
631 struct uart_amba_port *uap;
632 int baud = 38400;
633 int bits = 8;
634 int parity = 'n';
635 int flow = 'n';
636 int ret;
637
638 /*
639 * Check whether an invalid uart number has been specified, and
640 * if so, search for the first available port that does have
641 * console support.
642 */
643 if (co->index >= UART_NR)
644 co->index = 0;
645 uap = amba_ports[co->index];
646 if (!uap)
647 return -ENODEV;
648
649 ret = clk_prepare(uap->clk);
650 if (ret)
651 return ret;
652
653 uap->port.uartclk = clk_get_rate(uap->clk);
654
655 if (options)
656 uart_parse_options(options, &baud, &parity, &bits, &flow);
657 else
658 pl010_console_get_options(uap, &baud, &parity, &bits);
659
660 return uart_set_options(&uap->port, co, baud, parity, bits, flow);
661}
662
663static struct uart_driver amba_reg;
664static struct console amba_console = {
665 .name = "ttyAM",
666 .write = pl010_console_write,
667 .device = uart_console_device,
668 .setup = pl010_console_setup,
669 .flags = CON_PRINTBUFFER,
670 .index = -1,
671 .data = &amba_reg,
672};
673
674#define AMBA_CONSOLE &amba_console
675#else
676#define AMBA_CONSOLE NULL
677#endif
678
679static struct uart_driver amba_reg = {
680 .owner = THIS_MODULE,
681 .driver_name = "ttyAM",
682 .dev_name = "ttyAM",
683 .major = SERIAL_AMBA_MAJOR,
684 .minor = SERIAL_AMBA_MINOR,
685 .nr = UART_NR,
686 .cons = AMBA_CONSOLE,
687};
688
689static int pl010_probe(struct amba_device *dev, const struct amba_id *id)
690{
691 struct uart_amba_port *uap;
692 void __iomem *base;
693 int i, ret;
694
695 for (i = 0; i < ARRAY_SIZE(amba_ports); i++)
696 if (amba_ports[i] == NULL)
697 break;
698
699 if (i == ARRAY_SIZE(amba_ports)) {
700 ret = -EBUSY;
701 goto out;
702 }
703
704 uap = kzalloc(sizeof(struct uart_amba_port), GFP_KERNEL);
705 if (!uap) {
706 ret = -ENOMEM;
707 goto out;
708 }
709
710 base = ioremap(dev->res.start, resource_size(&dev->res));
711 if (!base) {
712 ret = -ENOMEM;
713 goto free;
714 }
715
716 uap->clk = clk_get(&dev->dev, NULL);
717 if (IS_ERR(uap->clk)) {
718 ret = PTR_ERR(uap->clk);
719 goto unmap;
720 }
721
722 uap->port.dev = &dev->dev;
723 uap->port.mapbase = dev->res.start;
724 uap->port.membase = base;
725 uap->port.iotype = UPIO_MEM;
726 uap->port.irq = dev->irq[0];
727 uap->port.fifosize = 16;
728 uap->port.ops = &amba_pl010_pops;
729 uap->port.flags = UPF_BOOT_AUTOCONF;
730 uap->port.line = i;
731 uap->dev = dev;
732 uap->data = dev->dev.platform_data;
733
734 amba_ports[i] = uap;
735
736 amba_set_drvdata(dev, uap);
737 ret = uart_add_one_port(&amba_reg, &uap->port);
738 if (ret) {
739 amba_set_drvdata(dev, NULL);
740 amba_ports[i] = NULL;
741 clk_put(uap->clk);
742 unmap:
743 iounmap(base);
744 free:
745 kfree(uap);
746 }
747 out:
748 return ret;
749}
750
751static int pl010_remove(struct amba_device *dev)
752{
753 struct uart_amba_port *uap = amba_get_drvdata(dev);
754 int i;
755
756 amba_set_drvdata(dev, NULL);
757
758 uart_remove_one_port(&amba_reg, &uap->port);
759
760 for (i = 0; i < ARRAY_SIZE(amba_ports); i++)
761 if (amba_ports[i] == uap)
762 amba_ports[i] = NULL;
763
764 iounmap(uap->port.membase);
765 clk_put(uap->clk);
766 kfree(uap);
767 return 0;
768}
769
770static int pl010_suspend(struct amba_device *dev, pm_message_t state)
771{
772 struct uart_amba_port *uap = amba_get_drvdata(dev);
773
774 if (uap)
775 uart_suspend_port(&amba_reg, &uap->port);
776
777 return 0;
778}
779
780static int pl010_resume(struct amba_device *dev)
781{
782 struct uart_amba_port *uap = amba_get_drvdata(dev);
783
784 if (uap)
785 uart_resume_port(&amba_reg, &uap->port);
786
787 return 0;
788}
789
790static struct amba_id pl010_ids[] = {
791 {
792 .id = 0x00041010,
793 .mask = 0x000fffff,
794 },
795 { 0, 0 },
796};
797
798MODULE_DEVICE_TABLE(amba, pl010_ids);
799
800static struct amba_driver pl010_driver = {
801 .drv = {
802 .name = "uart-pl010",
803 },
804 .id_table = pl010_ids,
805 .probe = pl010_probe,
806 .remove = pl010_remove,
807 .suspend = pl010_suspend,
808 .resume = pl010_resume,
809};
810
811static int __init pl010_init(void)
812{
813 int ret;
814
815 printk(KERN_INFO "Serial: AMBA driver\n");
816
817 ret = uart_register_driver(&amba_reg);
818 if (ret == 0) {
819 ret = amba_driver_register(&pl010_driver);
820 if (ret)
821 uart_unregister_driver(&amba_reg);
822 }
823 return ret;
824}
825
826static void __exit pl010_exit(void)
827{
828 amba_driver_unregister(&pl010_driver);
829 uart_unregister_driver(&amba_reg);
830}
831
832module_init(pl010_init);
833module_exit(pl010_exit);
834
835MODULE_AUTHOR("ARM Ltd/Deep Blue Solutions Ltd");
836MODULE_DESCRIPTION("ARM AMBA serial port driver");
837MODULE_LICENSE("GPL");