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v6.8
  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, rsr, max_count = 256;
116	u8 ch, flag;
117
118	status = readb(port->membase + UART01x_FR);
119	while (UART_RX_DATA(status) && max_count--) {
120		ch = readb(port->membase + UART01x_DR);
121		flag = TTY_NORMAL;
122
123		port->icount.rx++;
124
125		/*
126		 * Note that the error handling code is
127		 * out of the main execution path
128		 */
129		rsr = readb(port->membase + UART01x_RSR) | UART_DUMMY_RSR_RX;
130		if (unlikely(rsr & UART01x_RSR_ANY)) {
131			writel(0, port->membase + UART01x_ECR);
132
133			if (rsr & UART01x_RSR_BE) {
134				rsr &= ~(UART01x_RSR_FE | UART01x_RSR_PE);
135				port->icount.brk++;
136				if (uart_handle_break(port))
137					goto ignore_char;
138			} else if (rsr & UART01x_RSR_PE)
139				port->icount.parity++;
140			else if (rsr & UART01x_RSR_FE)
141				port->icount.frame++;
142			if (rsr & UART01x_RSR_OE)
143				port->icount.overrun++;
144
145			rsr &= port->read_status_mask;
146
147			if (rsr & UART01x_RSR_BE)
148				flag = TTY_BREAK;
149			else if (rsr & UART01x_RSR_PE)
150				flag = TTY_PARITY;
151			else if (rsr & UART01x_RSR_FE)
152				flag = TTY_FRAME;
153		}
154
155		if (uart_handle_sysrq_char(port, ch))
156			goto ignore_char;
157
158		uart_insert_char(port, rsr, UART01x_RSR_OE, ch, flag);
159
160	ignore_char:
161		status = readb(port->membase + UART01x_FR);
162	}
163	tty_flip_buffer_push(&port->state->port);
 
 
164}
165
166static void pl010_tx_chars(struct uart_port *port)
167{
168	u8 ch;
 
 
 
 
 
 
 
 
 
 
 
 
169
170	uart_port_tx_limited(port, ch, port->fifosize >> 1,
171		true,
172		writel(ch, port->membase + UART01x_DR),
173		({}));
 
 
 
 
 
 
 
 
 
 
174}
175
176static void pl010_modem_status(struct uart_amba_port *uap)
177{
178	struct uart_port *port = &uap->port;
179	unsigned int status, delta;
180
181	writel(0, port->membase + UART010_ICR);
182
183	status = readb(port->membase + UART01x_FR) & UART01x_FR_MODEM_ANY;
184
185	delta = status ^ uap->old_status;
186	uap->old_status = status;
187
188	if (!delta)
189		return;
190
191	if (delta & UART01x_FR_DCD)
192		uart_handle_dcd_change(port, status & UART01x_FR_DCD);
193
194	if (delta & UART01x_FR_DSR)
195		port->icount.dsr++;
196
197	if (delta & UART01x_FR_CTS)
198		uart_handle_cts_change(port, status & UART01x_FR_CTS);
199
200	wake_up_interruptible(&port->state->port.delta_msr_wait);
201}
202
203static irqreturn_t pl010_int(int irq, void *dev_id)
204{
205	struct uart_amba_port *uap = dev_id;
206	struct uart_port *port = &uap->port;
207	unsigned int status, pass_counter = AMBA_ISR_PASS_LIMIT;
208	int handled = 0;
209
210	uart_port_lock(port);
211
212	status = readb(port->membase + UART010_IIR);
213	if (status) {
214		do {
215			if (status & (UART010_IIR_RTIS | UART010_IIR_RIS))
216				pl010_rx_chars(port);
217			if (status & UART010_IIR_MIS)
218				pl010_modem_status(uap);
219			if (status & UART010_IIR_TIS)
220				pl010_tx_chars(port);
221
222			if (pass_counter-- == 0)
223				break;
224
225			status = readb(port->membase + UART010_IIR);
226		} while (status & (UART010_IIR_RTIS | UART010_IIR_RIS |
227				   UART010_IIR_TIS));
228		handled = 1;
229	}
230
231	uart_port_unlock(port);
232
233	return IRQ_RETVAL(handled);
234}
235
236static unsigned int pl010_tx_empty(struct uart_port *port)
237{
238	unsigned int status = readb(port->membase + UART01x_FR);
239
240	return status & UART01x_FR_BUSY ? 0 : TIOCSER_TEMT;
241}
242
243static unsigned int pl010_get_mctrl(struct uart_port *port)
244{
 
245	unsigned int result = 0;
246	unsigned int status;
247
248	status = readb(port->membase + UART01x_FR);
249	if (status & UART01x_FR_DCD)
250		result |= TIOCM_CAR;
251	if (status & UART01x_FR_DSR)
252		result |= TIOCM_DSR;
253	if (status & UART01x_FR_CTS)
254		result |= TIOCM_CTS;
255
256	return result;
257}
258
259static void pl010_set_mctrl(struct uart_port *port, unsigned int mctrl)
260{
261	struct uart_amba_port *uap =
262		container_of(port, struct uart_amba_port, port);
263
264	if (uap->data)
265		uap->data->set_mctrl(uap->dev, port->membase, mctrl);
266}
267
268static void pl010_break_ctl(struct uart_port *port, int break_state)
269{
 
270	unsigned long flags;
271	unsigned int lcr_h;
272
273	uart_port_lock_irqsave(port, &flags);
274	lcr_h = readb(port->membase + UART010_LCRH);
275	if (break_state == -1)
276		lcr_h |= UART01x_LCRH_BRK;
277	else
278		lcr_h &= ~UART01x_LCRH_BRK;
279	writel(lcr_h, port->membase + UART010_LCRH);
280	uart_port_unlock_irqrestore(port, flags);
281}
282
283static int pl010_startup(struct uart_port *port)
284{
285	struct uart_amba_port *uap =
286		container_of(port, struct uart_amba_port, port);
287	int retval;
288
289	/*
290	 * Try to enable the clock producer.
291	 */
292	retval = clk_prepare_enable(uap->clk);
293	if (retval)
294		goto out;
295
296	port->uartclk = clk_get_rate(uap->clk);
297
298	/*
299	 * Allocate the IRQ
300	 */
301	retval = request_irq(port->irq, pl010_int, 0, "uart-pl010", uap);
302	if (retval)
303		goto clk_dis;
304
305	/*
306	 * initialise the old status of the modem signals
307	 */
308	uap->old_status = readb(port->membase + UART01x_FR) & UART01x_FR_MODEM_ANY;
309
310	/*
311	 * Finally, enable interrupts
312	 */
313	writel(UART01x_CR_UARTEN | UART010_CR_RIE | UART010_CR_RTIE,
314	       port->membase + UART010_CR);
315
316	return 0;
317
318 clk_dis:
319	clk_disable_unprepare(uap->clk);
320 out:
321	return retval;
322}
323
324static void pl010_shutdown(struct uart_port *port)
325{
326	struct uart_amba_port *uap =
327		container_of(port, struct uart_amba_port, port);
328
329	/*
330	 * Free the interrupt
331	 */
332	free_irq(port->irq, uap);
333
334	/*
335	 * disable all interrupts, disable the port
336	 */
337	writel(0, port->membase + UART010_CR);
338
339	/* disable break condition and fifos */
340	writel(readb(port->membase + UART010_LCRH) &
341		~(UART01x_LCRH_BRK | UART01x_LCRH_FEN),
342	       port->membase + UART010_LCRH);
343
344	/*
345	 * Shut down the clock producer
346	 */
347	clk_disable_unprepare(uap->clk);
348}
349
350static void
351pl010_set_termios(struct uart_port *port, struct ktermios *termios,
352		  const struct ktermios *old)
353{
 
354	unsigned int lcr_h, old_cr;
355	unsigned long flags;
356	unsigned int baud, quot;
357
358	/*
359	 * Ask the core to calculate the divisor for us.
360	 */
361	baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk / 16);
362	quot = uart_get_divisor(port, baud);
363
364	switch (termios->c_cflag & CSIZE) {
365	case CS5:
366		lcr_h = UART01x_LCRH_WLEN_5;
367		break;
368	case CS6:
369		lcr_h = UART01x_LCRH_WLEN_6;
370		break;
371	case CS7:
372		lcr_h = UART01x_LCRH_WLEN_7;
373		break;
374	default: // CS8
375		lcr_h = UART01x_LCRH_WLEN_8;
376		break;
377	}
378	if (termios->c_cflag & CSTOPB)
379		lcr_h |= UART01x_LCRH_STP2;
380	if (termios->c_cflag & PARENB) {
381		lcr_h |= UART01x_LCRH_PEN;
382		if (!(termios->c_cflag & PARODD))
383			lcr_h |= UART01x_LCRH_EPS;
384	}
385	if (port->fifosize > 1)
386		lcr_h |= UART01x_LCRH_FEN;
387
388	uart_port_lock_irqsave(port, &flags);
389
390	/*
391	 * Update the per-port timeout.
392	 */
393	uart_update_timeout(port, termios->c_cflag, baud);
394
395	port->read_status_mask = UART01x_RSR_OE;
396	if (termios->c_iflag & INPCK)
397		port->read_status_mask |= UART01x_RSR_FE | UART01x_RSR_PE;
398	if (termios->c_iflag & (IGNBRK | BRKINT | PARMRK))
399		port->read_status_mask |= UART01x_RSR_BE;
400
401	/*
402	 * Characters to ignore
403	 */
404	port->ignore_status_mask = 0;
405	if (termios->c_iflag & IGNPAR)
406		port->ignore_status_mask |= UART01x_RSR_FE | UART01x_RSR_PE;
407	if (termios->c_iflag & IGNBRK) {
408		port->ignore_status_mask |= UART01x_RSR_BE;
409		/*
410		 * If we're ignoring parity and break indicators,
411		 * ignore overruns too (for real raw support).
412		 */
413		if (termios->c_iflag & IGNPAR)
414			port->ignore_status_mask |= UART01x_RSR_OE;
415	}
416
417	/*
418	 * Ignore all characters if CREAD is not set.
419	 */
420	if ((termios->c_cflag & CREAD) == 0)
421		port->ignore_status_mask |= UART_DUMMY_RSR_RX;
422
423	old_cr = readb(port->membase + UART010_CR) & ~UART010_CR_MSIE;
 
424
425	if (UART_ENABLE_MS(port, termios->c_cflag))
426		old_cr |= UART010_CR_MSIE;
427
 
 
428	/* Set baud rate */
429	quot -= 1;
430	writel((quot & 0xf00) >> 8, port->membase + UART010_LCRM);
431	writel(quot & 0xff, port->membase + UART010_LCRL);
432
433	/*
434	 * ----------v----------v----------v----------v-----
435	 * NOTE: MUST BE WRITTEN AFTER UARTLCR_M & UARTLCR_L
436	 * ----------^----------^----------^----------^-----
437	 */
438	writel(lcr_h, port->membase + UART010_LCRH);
439	writel(old_cr, port->membase + UART010_CR);
440
441	uart_port_unlock_irqrestore(port, flags);
442}
443
444static void pl010_set_ldisc(struct uart_port *port, struct ktermios *termios)
445{
446	if (termios->c_line == N_PPS) {
447		port->flags |= UPF_HARDPPS_CD;
448		uart_port_lock_irq(port);
449		pl010_enable_ms(port);
450		uart_port_unlock_irq(port);
451	} else {
452		port->flags &= ~UPF_HARDPPS_CD;
453		if (!UART_ENABLE_MS(port, termios->c_cflag)) {
454			uart_port_lock_irq(port);
455			pl010_disable_ms(port);
456			uart_port_unlock_irq(port);
457		}
458	}
459}
460
461static const char *pl010_type(struct uart_port *port)
462{
463	return port->type == PORT_AMBA ? "AMBA" : NULL;
464}
465
466/*
467 * Release the memory region(s) being used by 'port'
468 */
469static void pl010_release_port(struct uart_port *port)
470{
471	release_mem_region(port->mapbase, UART_PORT_SIZE);
472}
473
474/*
475 * Request the memory region(s) being used by 'port'
476 */
477static int pl010_request_port(struct uart_port *port)
478{
479	return request_mem_region(port->mapbase, UART_PORT_SIZE, "uart-pl010")
480			!= NULL ? 0 : -EBUSY;
481}
482
483/*
484 * Configure/autoconfigure the port.
485 */
486static void pl010_config_port(struct uart_port *port, int flags)
487{
488	if (flags & UART_CONFIG_TYPE) {
489		port->type = PORT_AMBA;
490		pl010_request_port(port);
491	}
492}
493
494/*
495 * verify the new serial_struct (for TIOCSSERIAL).
496 */
497static int pl010_verify_port(struct uart_port *port, struct serial_struct *ser)
498{
499	int ret = 0;
500	if (ser->type != PORT_UNKNOWN && ser->type != PORT_AMBA)
501		ret = -EINVAL;
502	if (ser->irq < 0 || ser->irq >= nr_irqs)
503		ret = -EINVAL;
504	if (ser->baud_base < 9600)
505		ret = -EINVAL;
506	return ret;
507}
508
509static const struct uart_ops amba_pl010_pops = {
510	.tx_empty	= pl010_tx_empty,
511	.set_mctrl	= pl010_set_mctrl,
512	.get_mctrl	= pl010_get_mctrl,
513	.stop_tx	= pl010_stop_tx,
514	.start_tx	= pl010_start_tx,
515	.stop_rx	= pl010_stop_rx,
516	.enable_ms	= pl010_enable_ms,
517	.break_ctl	= pl010_break_ctl,
518	.startup	= pl010_startup,
519	.shutdown	= pl010_shutdown,
520	.set_termios	= pl010_set_termios,
521	.set_ldisc	= pl010_set_ldisc,
522	.type		= pl010_type,
523	.release_port	= pl010_release_port,
524	.request_port	= pl010_request_port,
525	.config_port	= pl010_config_port,
526	.verify_port	= pl010_verify_port,
527};
528
529static struct uart_amba_port *amba_ports[UART_NR];
530
531#ifdef CONFIG_SERIAL_AMBA_PL010_CONSOLE
532
533static void pl010_console_putchar(struct uart_port *port, unsigned char ch)
534{
 
535	unsigned int status;
536
537	do {
538		status = readb(port->membase + UART01x_FR);
539		barrier();
540	} while (!UART_TX_READY(status));
541	writel(ch, port->membase + UART01x_DR);
542}
543
544static void
545pl010_console_write(struct console *co, const char *s, unsigned int count)
546{
547	struct uart_amba_port *uap = amba_ports[co->index];
548	struct uart_port *port = &uap->port;
549	unsigned int status, old_cr;
550
551	clk_enable(uap->clk);
552
553	/*
554	 *	First save the CR then disable the interrupts
555	 */
556	old_cr = readb(port->membase + UART010_CR);
557	writel(UART01x_CR_UARTEN, port->membase + UART010_CR);
558
559	uart_console_write(port, s, count, pl010_console_putchar);
560
561	/*
562	 *	Finally, wait for transmitter to become empty
563	 *	and restore the TCR
564	 */
565	do {
566		status = readb(port->membase + UART01x_FR);
567		barrier();
568	} while (status & UART01x_FR_BUSY);
569	writel(old_cr, port->membase + UART010_CR);
570
571	clk_disable(uap->clk);
572}
573
574static void __init
575pl010_console_get_options(struct uart_amba_port *uap, int *baud,
576			     int *parity, int *bits)
577{
578	if (readb(uap->port.membase + UART010_CR) & UART01x_CR_UARTEN) {
579		unsigned int lcr_h, quot;
580		lcr_h = readb(uap->port.membase + UART010_LCRH);
581
582		*parity = 'n';
583		if (lcr_h & UART01x_LCRH_PEN) {
584			if (lcr_h & UART01x_LCRH_EPS)
585				*parity = 'e';
586			else
587				*parity = 'o';
588		}
589
590		if ((lcr_h & 0x60) == UART01x_LCRH_WLEN_7)
591			*bits = 7;
592		else
593			*bits = 8;
594
595		quot = readb(uap->port.membase + UART010_LCRL) |
596		       readb(uap->port.membase + UART010_LCRM) << 8;
597		*baud = uap->port.uartclk / (16 * (quot + 1));
598	}
599}
600
601static int __init pl010_console_setup(struct console *co, char *options)
602{
603	struct uart_amba_port *uap;
604	int baud = 38400;
605	int bits = 8;
606	int parity = 'n';
607	int flow = 'n';
608	int ret;
609
610	/*
611	 * Check whether an invalid uart number has been specified, and
612	 * if so, search for the first available port that does have
613	 * console support.
614	 */
615	if (co->index >= UART_NR)
616		co->index = 0;
617	uap = amba_ports[co->index];
618	if (!uap)
619		return -ENODEV;
620
621	ret = clk_prepare(uap->clk);
622	if (ret)
623		return ret;
624
625	uap->port.uartclk = clk_get_rate(uap->clk);
626
627	if (options)
628		uart_parse_options(options, &baud, &parity, &bits, &flow);
629	else
630		pl010_console_get_options(uap, &baud, &parity, &bits);
631
632	return uart_set_options(&uap->port, co, baud, parity, bits, flow);
633}
634
635static struct uart_driver amba_reg;
636static struct console amba_console = {
637	.name		= "ttyAM",
638	.write		= pl010_console_write,
639	.device		= uart_console_device,
640	.setup		= pl010_console_setup,
641	.flags		= CON_PRINTBUFFER,
642	.index		= -1,
643	.data		= &amba_reg,
644};
645
646#define AMBA_CONSOLE	&amba_console
647#else
648#define AMBA_CONSOLE	NULL
649#endif
650
651static DEFINE_MUTEX(amba_reg_lock);
652static struct uart_driver amba_reg = {
653	.owner			= THIS_MODULE,
654	.driver_name		= "ttyAM",
655	.dev_name		= "ttyAM",
656	.major			= SERIAL_AMBA_MAJOR,
657	.minor			= SERIAL_AMBA_MINOR,
658	.nr			= UART_NR,
659	.cons			= AMBA_CONSOLE,
660};
661
662static int pl010_probe(struct amba_device *dev, const struct amba_id *id)
663{
664	struct uart_amba_port *uap;
665	void __iomem *base;
666	int i, ret;
667
668	for (i = 0; i < ARRAY_SIZE(amba_ports); i++)
669		if (amba_ports[i] == NULL)
670			break;
671
672	if (i == ARRAY_SIZE(amba_ports))
673		return -EBUSY;
 
 
674
675	uap = devm_kzalloc(&dev->dev, sizeof(struct uart_amba_port),
676			   GFP_KERNEL);
677	if (!uap)
678		return -ENOMEM;
 
 
 
 
 
 
 
679
680	base = devm_ioremap(&dev->dev, dev->res.start,
681			    resource_size(&dev->res));
682	if (!base)
683		return -ENOMEM;
684
685	uap->clk = devm_clk_get(&dev->dev, NULL);
686	if (IS_ERR(uap->clk))
687		return PTR_ERR(uap->clk);
688
689	uap->port.dev = &dev->dev;
690	uap->port.mapbase = dev->res.start;
691	uap->port.membase = base;
692	uap->port.iotype = UPIO_MEM;
693	uap->port.irq = dev->irq[0];
694	uap->port.fifosize = 16;
695	uap->port.has_sysrq = IS_ENABLED(CONFIG_SERIAL_AMBA_PL010_CONSOLE);
696	uap->port.ops = &amba_pl010_pops;
697	uap->port.flags = UPF_BOOT_AUTOCONF;
698	uap->port.line = i;
699	uap->dev = dev;
700	uap->data = dev_get_platdata(&dev->dev);
701
702	amba_ports[i] = uap;
703
704	amba_set_drvdata(dev, uap);
705
706	mutex_lock(&amba_reg_lock);
707	if (!amba_reg.state) {
708		ret = uart_register_driver(&amba_reg);
709		if (ret < 0) {
710			mutex_unlock(&amba_reg_lock);
711			dev_err(uap->port.dev,
712				"Failed to register AMBA-PL010 driver\n");
713			return ret;
714		}
715	}
716	mutex_unlock(&amba_reg_lock);
717
718	ret = uart_add_one_port(&amba_reg, &uap->port);
719	if (ret)
720		amba_ports[i] = NULL;
721
 
 
 
 
 
 
722	return ret;
723}
724
725static void pl010_remove(struct amba_device *dev)
726{
727	struct uart_amba_port *uap = amba_get_drvdata(dev);
728	int i;
729	bool busy = false;
730
731	uart_remove_one_port(&amba_reg, &uap->port);
732
733	for (i = 0; i < ARRAY_SIZE(amba_ports); i++)
734		if (amba_ports[i] == uap)
735			amba_ports[i] = NULL;
736		else if (amba_ports[i])
737			busy = true;
738
739	if (!busy)
740		uart_unregister_driver(&amba_reg);
 
 
741}
742
743#ifdef CONFIG_PM_SLEEP
744static int pl010_suspend(struct device *dev)
745{
746	struct uart_amba_port *uap = dev_get_drvdata(dev);
747
748	if (uap)
749		uart_suspend_port(&amba_reg, &uap->port);
750
751	return 0;
752}
753
754static int pl010_resume(struct device *dev)
755{
756	struct uart_amba_port *uap = dev_get_drvdata(dev);
757
758	if (uap)
759		uart_resume_port(&amba_reg, &uap->port);
760
761	return 0;
762}
763#endif
764
765static SIMPLE_DEV_PM_OPS(pl010_dev_pm_ops, pl010_suspend, pl010_resume);
766
767static const struct amba_id pl010_ids[] = {
768	{
769		.id	= 0x00041010,
770		.mask	= 0x000fffff,
771	},
772	{ 0, 0 },
773};
774
775MODULE_DEVICE_TABLE(amba, pl010_ids);
776
777static struct amba_driver pl010_driver = {
778	.drv = {
779		.name	= "uart-pl010",
780		.pm	= &pl010_dev_pm_ops,
781	},
782	.id_table	= pl010_ids,
783	.probe		= pl010_probe,
784	.remove		= pl010_remove,
785};
786
787static int __init pl010_init(void)
788{
 
 
789	printk(KERN_INFO "Serial: AMBA driver\n");
790
791	return  amba_driver_register(&pl010_driver);
 
 
 
 
 
 
792}
793
794static void __exit pl010_exit(void)
795{
796	amba_driver_unregister(&pl010_driver);
 
797}
798
799module_init(pl010_init);
800module_exit(pl010_exit);
801
802MODULE_AUTHOR("ARM Ltd/Deep Blue Solutions Ltd");
803MODULE_DESCRIPTION("ARM AMBA serial port driver");
804MODULE_LICENSE("GPL");
v3.15
 
  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");