1/*
2 *  linux/drivers/char/atmel_serial.c
3 *
4 *  Driver for Atmel AT91 / AT32 Serial ports
5 *  Copyright (C) 2003 Rick Bronson
6 *
7 *  Based on drivers/char/serial_sa1100.c, by Deep Blue Solutions Ltd.
8 *  Based on drivers/char/serial.c, by Linus Torvalds, Theodore Ts'o.
9 *
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License as published by
12 * the Free Software Foundation; either version 2 of the License, or
13 * (at your option) any later version.
14 *
15 * This program is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
18 * GNU General Public License for more details.
19 *
20 * You should have received a copy of the GNU General Public License
21 * along with this program; if not, write to the Free Software
22 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
23 *
24 */
25#include <linux/module.h>
26#include <linux/tty.h>
27#include <linux/ioport.h>
28#include <linux/slab.h>
29#include <linux/init.h>
30#include <linux/serial.h>
31#include <linux/clk.h>
32#include <linux/console.h>
33#include <linux/sysrq.h>
34#include <linux/tty_flip.h>
35#include <linux/platform_device.h>
36#include <linux/atmel_pdc.h>
37
38#include <asm/io.h>
39
40#include <asm/mach/serial_at91.h>
41#include <asm/arch/board.h>
42
43#ifdef CONFIG_ARM
44#include <asm/arch/cpu.h>
45#include <asm/arch/gpio.h>
46#endif
47
48#include "atmel_serial.h"
49
50#if defined(CONFIG_SERIAL_ATMEL_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
51#define SUPPORT_SYSRQ
52#endif
53
54#include <linux/serial_core.h>
55
56#ifdef CONFIG_SERIAL_ATMEL_TTYAT
57
58/* Use device name ttyAT, major 204 and minor 154-169.  This is necessary if we
59 * should coexist with the 8250 driver, such as if we have an external 16C550
60 * UART. */
61#define SERIAL_ATMEL_MAJOR	204
62#define MINOR_START		154
63#define ATMEL_DEVICENAME	"ttyAT"
64
65#else
66
67/* Use device name ttyS, major 4, minor 64-68.  This is the usual serial port
68 * name, but it is legally reserved for the 8250 driver. */
69#define SERIAL_ATMEL_MAJOR	TTY_MAJOR
70#define MINOR_START		64
71#define ATMEL_DEVICENAME	"ttyS"
72
73#endif
74
75#define ATMEL_ISR_PASS_LIMIT	256
76
77#define UART_PUT_CR(port,v)	__raw_writel(v, (port)->membase + ATMEL_US_CR)
78#define UART_GET_MR(port)	__raw_readl((port)->membase + ATMEL_US_MR)
79#define UART_PUT_MR(port,v)	__raw_writel(v, (port)->membase + ATMEL_US_MR)
80#define UART_PUT_IER(port,v)	__raw_writel(v, (port)->membase + ATMEL_US_IER)
81#define UART_PUT_IDR(port,v)	__raw_writel(v, (port)->membase + ATMEL_US_IDR)
82#define UART_GET_IMR(port)	__raw_readl((port)->membase + ATMEL_US_IMR)
83#define UART_GET_CSR(port)	__raw_readl((port)->membase + ATMEL_US_CSR)
84#define UART_GET_CHAR(port)	__raw_readl((port)->membase + ATMEL_US_RHR)
85#define UART_PUT_CHAR(port,v)	__raw_writel(v, (port)->membase + ATMEL_US_THR)
86#define UART_GET_BRGR(port)	__raw_readl((port)->membase + ATMEL_US_BRGR)
87#define UART_PUT_BRGR(port,v)	__raw_writel(v, (port)->membase + ATMEL_US_BRGR)
88#define UART_PUT_RTOR(port,v)	__raw_writel(v, (port)->membase + ATMEL_US_RTOR)
89
90// #define UART_GET_CR(port)	__raw_readl((port)->membase + ATMEL_US_CR)		// is write-only
91
92 /* PDC registers */
93#define UART_PUT_PTCR(port,v)	__raw_writel(v, (port)->membase + ATMEL_PDC_PTCR)
94#define UART_GET_PTSR(port)	__raw_readl((port)->membase + ATMEL_PDC_PTSR)
95
96#define UART_PUT_RPR(port,v)	__raw_writel(v, (port)->membase + ATMEL_PDC_RPR)
97#define UART_GET_RPR(port)	__raw_readl((port)->membase + ATMEL_PDC_RPR)
98#define UART_PUT_RCR(port,v)	__raw_writel(v, (port)->membase + ATMEL_PDC_RCR)
99#define UART_PUT_RNPR(port,v)	__raw_writel(v, (port)->membase + ATMEL_PDC_RNPR)
100#define UART_PUT_RNCR(port,v)	__raw_writel(v, (port)->membase + ATMEL_PDC_RNCR)
101
102#define UART_PUT_TPR(port,v)	__raw_writel(v, (port)->membase + ATMEL_PDC_TPR)
103#define UART_PUT_TCR(port,v)	__raw_writel(v, (port)->membase + ATMEL_PDC_TCR)
104//#define UART_PUT_TNPR(port,v)	__raw_writel(v, (port)->membase + ATMEL_PDC_TNPR)
105//#define UART_PUT_TNCR(port,v)	__raw_writel(v, (port)->membase + ATMEL_PDC_TNCR)
106
107static int (*atmel_open_hook)(struct uart_port *);
108static void (*atmel_close_hook)(struct uart_port *);
109
110/*
111 * We wrap our port structure around the generic uart_port.
112 */
113struct atmel_uart_port {
114	struct uart_port	uart;		/* uart */
115	struct clk		*clk;		/* uart clock */
116	unsigned short		suspended;	/* is port suspended? */
117};
118
119static struct atmel_uart_port atmel_ports[ATMEL_MAX_UART];
120
121#ifdef SUPPORT_SYSRQ
122static struct console atmel_console;
123#endif
124
125/*
126 * Return TIOCSER_TEMT when transmitter FIFO and Shift register is empty.
127 */
128static u_int atmel_tx_empty(struct uart_port *port)
129{
130	return (UART_GET_CSR(port) & ATMEL_US_TXEMPTY) ? TIOCSER_TEMT : 0;
131}
132
133/*
134 * Set state of the modem control output lines
135 */
136static void atmel_set_mctrl(struct uart_port *port, u_int mctrl)
137{
138	unsigned int control = 0;
139	unsigned int mode;
140
141#ifdef CONFIG_ARCH_AT91RM9200
142	if (cpu_is_at91rm9200()) {
143		/*
144		 * AT91RM9200 Errata #39: RTS0 is not internally connected to PA21.
145		 *  We need to drive the pin manually.
146		 */
147		if (port->mapbase == AT91RM9200_BASE_US0) {
148			if (mctrl & TIOCM_RTS)
149				at91_set_gpio_value(AT91_PIN_PA21, 0);
150			else
151				at91_set_gpio_value(AT91_PIN_PA21, 1);
152		}
153	}
154#endif
155
156	if (mctrl & TIOCM_RTS)
157		control |= ATMEL_US_RTSEN;
158	else
159		control |= ATMEL_US_RTSDIS;
160
161	if (mctrl & TIOCM_DTR)
162		control |= ATMEL_US_DTREN;
163	else
164		control |= ATMEL_US_DTRDIS;
165
166	UART_PUT_CR(port, control);
167
168	/* Local loopback mode? */
169	mode = UART_GET_MR(port) & ~ATMEL_US_CHMODE;
170	if (mctrl & TIOCM_LOOP)
171		mode |= ATMEL_US_CHMODE_LOC_LOOP;
172	else
173		mode |= ATMEL_US_CHMODE_NORMAL;
174	UART_PUT_MR(port, mode);
175}
176
177/*
178 * Get state of the modem control input lines
179 */
180static u_int atmel_get_mctrl(struct uart_port *port)
181{
182	unsigned int status, ret = 0;
183
184	status = UART_GET_CSR(port);
185
186	/*
187	 * The control signals are active low.
188	 */
189	if (!(status & ATMEL_US_DCD))
190		ret |= TIOCM_CD;
191	if (!(status & ATMEL_US_CTS))
192		ret |= TIOCM_CTS;
193	if (!(status & ATMEL_US_DSR))
194		ret |= TIOCM_DSR;
195	if (!(status & ATMEL_US_RI))
196		ret |= TIOCM_RI;
197
198	return ret;
199}
200
201/*
202 * Stop transmitting.
203 */
204static void atmel_stop_tx(struct uart_port *port)
205{
206	struct atmel_uart_port *atmel_port = (struct atmel_uart_port *) port;
207
208	UART_PUT_IDR(port, ATMEL_US_TXRDY);
209}
210
211/*
212 * Start transmitting.
213 */
214static void atmel_start_tx(struct uart_port *port)
215{
216	struct atmel_uart_port *atmel_port = (struct atmel_uart_port *) port;
217
218	UART_PUT_IER(port, ATMEL_US_TXRDY);
219}
220
221/*
222 * Stop receiving - port is in process of being closed.
223 */
224static void atmel_stop_rx(struct uart_port *port)
225{
226	struct atmel_uart_port *atmel_port = (struct atmel_uart_port *) port;
227
228	UART_PUT_IDR(port, ATMEL_US_RXRDY);
229}
230
231/*
232 * Enable modem status interrupts
233 */
234static void atmel_enable_ms(struct uart_port *port)
235{
236	UART_PUT_IER(port, ATMEL_US_RIIC | ATMEL_US_DSRIC | ATMEL_US_DCDIC | ATMEL_US_CTSIC);
237}
238
239/*
240 * Control the transmission of a break signal
241 */
242static void atmel_break_ctl(struct uart_port *port, int break_state)
243{
244	if (break_state != 0)
245		UART_PUT_CR(port, ATMEL_US_STTBRK);	/* start break */
246	else
247		UART_PUT_CR(port, ATMEL_US_STPBRK);	/* stop break */
248}
249
250/*
251 * Characters received (called from interrupt handler)
252 */
253static void atmel_rx_chars(struct uart_port *port)
254{
255	struct tty_struct *tty = port->info->tty;
256	unsigned int status, ch, flg;
257
258	status = UART_GET_CSR(port);
259	while (status & ATMEL_US_RXRDY) {
260		ch = UART_GET_CHAR(port);
261
262		port->icount.rx++;
263
264		flg = TTY_NORMAL;
265
266		/*
267		 * note that the error handling code is
268		 * out of the main execution path
269		 */
270		if (unlikely(status & (ATMEL_US_PARE | ATMEL_US_FRAME | ATMEL_US_OVRE | ATMEL_US_RXBRK))) {
271			UART_PUT_CR(port, ATMEL_US_RSTSTA);	/* clear error */
272			if (status & ATMEL_US_RXBRK) {
273				status &= ~(ATMEL_US_PARE | ATMEL_US_FRAME);	/* ignore side-effect */
274				port->icount.brk++;
275				if (uart_handle_break(port))
276					goto ignore_char;
277			}
278			if (status & ATMEL_US_PARE)
279				port->icount.parity++;
280			if (status & ATMEL_US_FRAME)
281				port->icount.frame++;
282			if (status & ATMEL_US_OVRE)
283				port->icount.overrun++;
284
285			status &= port->read_status_mask;
286
287			if (status & ATMEL_US_RXBRK)
288				flg = TTY_BREAK;
289			else if (status & ATMEL_US_PARE)
290				flg = TTY_PARITY;
291			else if (status & ATMEL_US_FRAME)
292				flg = TTY_FRAME;
293		}
294
295		if (uart_handle_sysrq_char(port, ch))
296			goto ignore_char;
297
298		uart_insert_char(port, status, ATMEL_US_OVRE, ch, flg);
299
300	ignore_char:
301		status = UART_GET_CSR(port);
302	}
303
304	tty_flip_buffer_push(tty);
305}
306
307/*
308 * Transmit characters (called from interrupt handler)
309 */
310static void atmel_tx_chars(struct uart_port *port)
311{
312	struct circ_buf *xmit = &port->info->xmit;
313
314	if (port->x_char) {
315		UART_PUT_CHAR(port, port->x_char);
316		port->icount.tx++;
317		port->x_char = 0;
318		return;
319	}
320	if (uart_circ_empty(xmit) || uart_tx_stopped(port)) {
321		atmel_stop_tx(port);
322		return;
323	}
324
325	while (UART_GET_CSR(port) & ATMEL_US_TXRDY) {
326		UART_PUT_CHAR(port, xmit->buf[xmit->tail]);
327		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
328		port->icount.tx++;
329		if (uart_circ_empty(xmit))
330			break;
331	}
332
333	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
334		uart_write_wakeup(port);
335
336	if (uart_circ_empty(xmit))
337		atmel_stop_tx(port);
338}
339
340/*
341 * Interrupt handler
342 */
343static irqreturn_t atmel_interrupt(int irq, void *dev_id)
344{
345	struct uart_port *port = dev_id;
346	struct atmel_uart_port *atmel_port = (struct atmel_uart_port *) port;
347	unsigned int status, pending, pass_counter = 0;
348
349	status = UART_GET_CSR(port);
350	pending = status & UART_GET_IMR(port);
351	while (pending) {
352		/* Interrupt receive */
353		if (pending & ATMEL_US_RXRDY)
354			atmel_rx_chars(port);
355
356		// TODO: All reads to CSR will clear these interrupts!
357		if (pending & ATMEL_US_RIIC) port->icount.rng++;
358		if (pending & ATMEL_US_DSRIC) port->icount.dsr++;
359		if (pending & ATMEL_US_DCDIC)
360			uart_handle_dcd_change(port, !(status & ATMEL_US_DCD));
361		if (pending & ATMEL_US_CTSIC)
362			uart_handle_cts_change(port, !(status & ATMEL_US_CTS));
363		if (pending & (ATMEL_US_RIIC | ATMEL_US_DSRIC | ATMEL_US_DCDIC | ATMEL_US_CTSIC))
364			wake_up_interruptible(&port->info->delta_msr_wait);
365
366		/* Interrupt transmit */
367		if (pending & ATMEL_US_TXRDY)
368			atmel_tx_chars(port);
369
370		if (pass_counter++ > ATMEL_ISR_PASS_LIMIT)
371			break;
372
373		status = UART_GET_CSR(port);
374		pending = status & UART_GET_IMR(port);
375	}
376	return IRQ_HANDLED;
377}
378
379/*
380 * Perform initialization and enable port for reception
381 */
382static int atmel_startup(struct uart_port *port)
383{
384	struct atmel_uart_port *atmel_port = (struct atmel_uart_port *) port;
385	int retval;
386
387	/*
388	 * Ensure that no interrupts are enabled otherwise when
389	 * request_irq() is called we could get stuck trying to
390	 * handle an unexpected interrupt
391	 */
392	UART_PUT_IDR(port, -1);
393
394	/*
395	 * Allocate the IRQ
396	 */
397	retval = request_irq(port->irq, atmel_interrupt, IRQF_SHARED, "atmel_serial", port);
398	if (retval) {
399		printk("atmel_serial: atmel_startup - Can't get irq\n");
400		return retval;
401	}
402
403	/*
404	 * If there is a specific "open" function (to register
405	 * control line interrupts)
406	 */
407	if (atmel_open_hook) {
408		retval = atmel_open_hook(port);
409		if (retval) {
410			free_irq(port->irq, port);
411			return retval;
412		}
413	}
414
415	/*
416	 * Finally, enable the serial port
417	 */
418	UART_PUT_CR(port, ATMEL_US_RSTSTA | ATMEL_US_RSTRX);
419	UART_PUT_CR(port, ATMEL_US_TXEN | ATMEL_US_RXEN);		/* enable xmit & rcvr */
420
421	UART_PUT_IER(port, ATMEL_US_RXRDY);		/* enable receive only */
422
423	return 0;
424}
425
426/*
427 * Disable the port
428 */
429static void atmel_shutdown(struct uart_port *port)
430{
431	struct atmel_uart_port *atmel_port = (struct atmel_uart_port *) port;
432
433	/*
434	 * Disable all interrupts, port and break condition.
435	 */
436	UART_PUT_CR(port, ATMEL_US_RSTSTA);
437	UART_PUT_IDR(port, -1);
438
439	/*
440	 * Free the interrupt
441	 */
442	free_irq(port->irq, port);
443
444	/*
445	 * If there is a specific "close" function (to unregister
446	 * control line interrupts)
447	 */
448	if (atmel_close_hook)
449		atmel_close_hook(port);
450}
451
452/*
453 * Power / Clock management.
454 */
455static void atmel_serial_pm(struct uart_port *port, unsigned int state, unsigned int oldstate)
456{
457	struct atmel_uart_port *atmel_port = (struct atmel_uart_port *) port;
458
459	switch (state) {
460		case 0:
461			/*
462			 * Enable the peripheral clock for this serial port.
463			 * This is called on uart_open() or a resume event.
464			 */
465			clk_enable(atmel_port->clk);
466			break;
467		case 3:
468			/*
469			 * Disable the peripheral clock for this serial port.
470			 * This is called on uart_close() or a suspend event.
471			 */
472			clk_disable(atmel_port->clk);
473			break;
474		default:
475			printk(KERN_ERR "atmel_serial: unknown pm %d\n", state);
476	}
477}
478
479/*
480 * Change the port parameters
481 */
482static void atmel_set_termios(struct uart_port *port, struct ktermios * termios, struct ktermios * old)
483{
484	unsigned long flags;
485	unsigned int mode, imr, quot, baud;
486
487	/* Get current mode register */
488	mode = UART_GET_MR(port) & ~(ATMEL_US_USCLKS | ATMEL_US_CHRL | ATMEL_US_NBSTOP | ATMEL_US_PAR);
489
490	baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk/16);
491	quot = uart_get_divisor(port, baud);
492
493	if (quot > 65535) {		/* BRGR is 16-bit, so switch to slower clock */
494		quot /= 8;
495		mode |= ATMEL_US_USCLKS_MCK_DIV8;
496	}
497
498	/* byte size */
499	switch (termios->c_cflag & CSIZE) {
500	case CS5:
501		mode |= ATMEL_US_CHRL_5;
502		break;
503	case CS6:
504		mode |= ATMEL_US_CHRL_6;
505		break;
506	case CS7:
507		mode |= ATMEL_US_CHRL_7;
508		break;
509	default:
510		mode |= ATMEL_US_CHRL_8;
511		break;
512	}
513
514	/* stop bits */
515	if (termios->c_cflag & CSTOPB)
516		mode |= ATMEL_US_NBSTOP_2;
517
518	/* parity */
519	if (termios->c_cflag & PARENB) {
520		if (termios->c_cflag & CMSPAR) {			/* Mark or Space parity */
521			if (termios->c_cflag & PARODD)
522				mode |= ATMEL_US_PAR_MARK;
523			else
524				mode |= ATMEL_US_PAR_SPACE;
525		}
526		else if (termios->c_cflag & PARODD)
527			mode |= ATMEL_US_PAR_ODD;
528		else
529			mode |= ATMEL_US_PAR_EVEN;
530	}
531	else
532		mode |= ATMEL_US_PAR_NONE;
533
534	spin_lock_irqsave(&port->lock, flags);
535
536	port->read_status_mask = ATMEL_US_OVRE;
537	if (termios->c_iflag & INPCK)
538		port->read_status_mask |= (ATMEL_US_FRAME | ATMEL_US_PARE);
539	if (termios->c_iflag & (BRKINT | PARMRK))
540		port->read_status_mask |= ATMEL_US_RXBRK;
541
542	/*
543	 * Characters to ignore
544	 */
545	port->ignore_status_mask = 0;
546	if (termios->c_iflag & IGNPAR)
547		port->ignore_status_mask |= (ATMEL_US_FRAME | ATMEL_US_PARE);
548	if (termios->c_iflag & IGNBRK) {
549		port->ignore_status_mask |= ATMEL_US_RXBRK;
550		/*
551		 * If we're ignoring parity and break indicators,
552		 * ignore overruns too (for real raw support).
553		 */
554		if (termios->c_iflag & IGNPAR)
555			port->ignore_status_mask |= ATMEL_US_OVRE;
556	}
557
558	// TODO: Ignore all characters if CREAD is set.
559
560	/* update the per-port timeout */
561	uart_update_timeout(port, termios->c_cflag, baud);
562
563	/* disable interrupts and drain transmitter */
564	imr = UART_GET_IMR(port);	/* get interrupt mask */
565	UART_PUT_IDR(port, -1);		/* disable all interrupts */
566	while (!(UART_GET_CSR(port) & ATMEL_US_TXEMPTY)) { barrier(); }
567
568	/* disable receiver and transmitter */
569	UART_PUT_CR(port, ATMEL_US_TXDIS | ATMEL_US_RXDIS);
570
571	/* set the parity, stop bits and data size */
572	UART_PUT_MR(port, mode);
573
574	/* set the baud rate */
575	UART_PUT_BRGR(port, quot);
576	UART_PUT_CR(port, ATMEL_US_RSTSTA | ATMEL_US_RSTRX);
577	UART_PUT_CR(port, ATMEL_US_TXEN | ATMEL_US_RXEN);
578
579	/* restore interrupts */
580	UART_PUT_IER(port, imr);
581
582	/* CTS flow-control and modem-status interrupts */
583	if (UART_ENABLE_MS(port, termios->c_cflag))
584		port->ops->enable_ms(port);
585
586	spin_unlock_irqrestore(&port->lock, flags);
587}
588
589/*
590 * Return string describing the specified port
591 */
592static const char *atmel_type(struct uart_port *port)
593{
594	return (port->type == PORT_ATMEL) ? "ATMEL_SERIAL" : NULL;
595}
596
597/*
598 * Release the memory region(s) being used by 'port'.
599 */
600static void atmel_release_port(struct uart_port *port)
601{
602	struct platform_device *pdev = to_platform_device(port->dev);
603	int size = pdev->resource[0].end - pdev->resource[0].start + 1;
604
605	release_mem_region(port->mapbase, size);
606
607	if (port->flags & UPF_IOREMAP) {
608		iounmap(port->membase);
609		port->membase = NULL;
610	}
611}
612
613/*
614 * Request the memory region(s) being used by 'port'.
615 */
616static int atmel_request_port(struct uart_port *port)
617{
618	struct platform_device *pdev = to_platform_device(port->dev);
619	int size = pdev->resource[0].end - pdev->resource[0].start + 1;
620
621	if (!request_mem_region(port->mapbase, size, "atmel_serial"))
622		return -EBUSY;
623
624	if (port->flags & UPF_IOREMAP) {
625		port->membase = ioremap(port->mapbase, size);
626		if (port->membase == NULL) {
627			release_mem_region(port->mapbase, size);
628			return -ENOMEM;
629		}
630	}
631
632	return 0;
633}
634
635/*
636 * Configure/autoconfigure the port.
637 */
638static void atmel_config_port(struct uart_port *port, int flags)
639{
640	if (flags & UART_CONFIG_TYPE) {
641		port->type = PORT_ATMEL;
642		atmel_request_port(port);
643	}
644}
645
646/*
647 * Verify the new serial_struct (for TIOCSSERIAL).
648 */
649static int atmel_verify_port(struct uart_port *port, struct serial_struct *ser)
650{
651	int ret = 0;
652	if (ser->type != PORT_UNKNOWN && ser->type != PORT_ATMEL)
653		ret = -EINVAL;
654	if (port->irq != ser->irq)
655		ret = -EINVAL;
656	if (ser->io_type != SERIAL_IO_MEM)
657		ret = -EINVAL;
658	if (port->uartclk / 16 != ser->baud_base)
659		ret = -EINVAL;
660	if ((void *)port->mapbase != ser->iomem_base)
661		ret = -EINVAL;
662	if (port->iobase != ser->port)
663		ret = -EINVAL;
664	if (ser->hub6 != 0)
665		ret = -EINVAL;
666	return ret;
667}
668
669static struct uart_ops atmel_pops = {
670	.tx_empty	= atmel_tx_empty,
671	.set_mctrl	= atmel_set_mctrl,
672	.get_mctrl	= atmel_get_mctrl,
673	.stop_tx	= atmel_stop_tx,
674	.start_tx	= atmel_start_tx,
675	.stop_rx	= atmel_stop_rx,
676	.enable_ms	= atmel_enable_ms,
677	.break_ctl	= atmel_break_ctl,
678	.startup	= atmel_startup,
679	.shutdown	= atmel_shutdown,
680	.set_termios	= atmel_set_termios,
681	.type		= atmel_type,
682	.release_port	= atmel_release_port,
683	.request_port	= atmel_request_port,
684	.config_port	= atmel_config_port,
685	.verify_port	= atmel_verify_port,
686	.pm		= atmel_serial_pm,
687};
688
689/*
690 * Configure the port from the platform device resource info.
691 */
692static void __devinit atmel_init_port(struct atmel_uart_port *atmel_port, struct platform_device *pdev)
693{
694	struct uart_port *port = &atmel_port->uart;
695	struct atmel_uart_data *data = pdev->dev.platform_data;
696
697	port->iotype	= UPIO_MEM;
698	port->flags	= UPF_BOOT_AUTOCONF;
699	port->ops	= &atmel_pops;
700	port->fifosize	= 1;
701	port->line	= pdev->id;
702	port->dev	= &pdev->dev;
703
704	port->mapbase	= pdev->resource[0].start;
705	port->irq	= pdev->resource[1].start;
706
707	if (data->regs)
708		/* Already mapped by setup code */
709		port->membase = data->regs;
710	else {
711		port->flags	|= UPF_IOREMAP;
712		port->membase	= NULL;
713	}
714
715	if (!atmel_port->clk) {		/* for console, the clock could already be configured */
716		atmel_port->clk = clk_get(&pdev->dev, "usart");
717		clk_enable(atmel_port->clk);
718		port->uartclk = clk_get_rate(atmel_port->clk);
719	}
720}
721
722/*
723 * Register board-specific modem-control line handlers.
724 */
725void __init atmel_register_uart_fns(struct atmel_port_fns *fns)
726{
727	if (fns->enable_ms)
728		atmel_pops.enable_ms = fns->enable_ms;
729	if (fns->get_mctrl)
730		atmel_pops.get_mctrl = fns->get_mctrl;
731	if (fns->set_mctrl)
732		atmel_pops.set_mctrl = fns->set_mctrl;
733	atmel_open_hook		= fns->open;
734	atmel_close_hook	= fns->close;
735	atmel_pops.pm		= fns->pm;
736	atmel_pops.set_wake	= fns->set_wake;
737}
738
739
740#ifdef CONFIG_SERIAL_ATMEL_CONSOLE
741static void atmel_console_putchar(struct uart_port *port, int ch)
742{
743	while (!(UART_GET_CSR(port) & ATMEL_US_TXRDY))
744		barrier();
745	UART_PUT_CHAR(port, ch);
746}
747
748/*
749 * Interrupts are disabled on entering
750 */
751static void atmel_console_write(struct console *co, const char *s, u_int count)
752{
753	struct uart_port *port = &atmel_ports[co->index].uart;
754	unsigned int status, imr;
755
756	/*
757	 *	First, save IMR and then disable interrupts
758	 */
759	imr = UART_GET_IMR(port);	/* get interrupt mask */
760	UART_PUT_IDR(port, ATMEL_US_RXRDY | ATMEL_US_TXRDY);
761
762	uart_console_write(port, s, count, atmel_console_putchar);
763
764	/*
765	 *	Finally, wait for transmitter to become empty
766	 *	and restore IMR
767	 */
768	do {
769		status = UART_GET_CSR(port);
770	} while (!(status & ATMEL_US_TXRDY));
771	UART_PUT_IER(port, imr);	/* set interrupts back the way they were */
772}
773
774/*
775 * If the port was already initialised (eg, by a boot loader), try to determine
776 * the current setup.
777 */
778static void __init atmel_console_get_options(struct uart_port *port, int *baud, int *parity, int *bits)
779{
780	unsigned int mr, quot;
781
782// TODO: CR is a write-only register
783//	unsigned int cr;
784//
785//	cr = UART_GET_CR(port) & (ATMEL_US_RXEN | ATMEL_US_TXEN);
786//	if (cr == (ATMEL_US_RXEN | ATMEL_US_TXEN)) {
787//		/* ok, the port was enabled */
788//	}
789
790	mr = UART_GET_MR(port) & ATMEL_US_CHRL;
791	if (mr == ATMEL_US_CHRL_8)
792		*bits = 8;
793	else
794		*bits = 7;
795
796	mr = UART_GET_MR(port) & ATMEL_US_PAR;
797	if (mr == ATMEL_US_PAR_EVEN)
798		*parity = 'e';
799	else if (mr == ATMEL_US_PAR_ODD)
800		*parity = 'o';
801
802	/*
803	 * The serial core only rounds down when matching this to a
804	 * supported baud rate. Make sure we don't end up slightly
805	 * lower than one of those, as it would make us fall through
806	 * to a much lower baud rate than we really want.
807	 */
808	quot = UART_GET_BRGR(port);
809	*baud = port->uartclk / (16 * (quot - 1));
810}
811
812static int __init atmel_console_setup(struct console *co, char *options)
813{
814	struct uart_port *port = &atmel_ports[co->index].uart;
815	int baud = 115200;
816	int bits = 8;
817	int parity = 'n';
818	int flow = 'n';
819
820	if (port->membase == 0)		/* Port not initialized yet - delay setup */
821		return -ENODEV;
822
823	UART_PUT_IDR(port, -1);				/* disable interrupts */
824	UART_PUT_CR(port, ATMEL_US_RSTSTA | ATMEL_US_RSTRX);
825	UART_PUT_CR(port, ATMEL_US_TXEN | ATMEL_US_RXEN);
826
827	if (options)
828		uart_parse_options(options, &baud, &parity, &bits, &flow);
829	else
830		atmel_console_get_options(port, &baud, &parity, &bits);
831
832	return uart_set_options(port, co, baud, parity, bits, flow);
833}
834
835static struct uart_driver atmel_uart;
836
837static struct console atmel_console = {
838	.name		= ATMEL_DEVICENAME,
839	.write		= atmel_console_write,
840	.device		= uart_console_device,
841	.setup		= atmel_console_setup,
842	.flags		= CON_PRINTBUFFER,
843	.index		= -1,
844	.data		= &atmel_uart,
845};
846
847#define ATMEL_CONSOLE_DEVICE	&atmel_console
848
849/*
850 * Early console initialization (before VM subsystem initialized).
851 */
852static int __init atmel_console_init(void)
853{
854	if (atmel_default_console_device) {
855		add_preferred_console(ATMEL_DEVICENAME, atmel_default_console_device->id, NULL);
856		atmel_init_port(&(atmel_ports[atmel_default_console_device->id]), atmel_default_console_device);
857		register_console(&atmel_console);
858	}
859
860	return 0;
861}
862console_initcall(atmel_console_init);
863
864/*
865 * Late console initialization.
866 */
867static int __init atmel_late_console_init(void)
868{
869	if (atmel_default_console_device && !(atmel_console.flags & CON_ENABLED))
870		register_console(&atmel_console);
871
872	return 0;
873}
874core_initcall(atmel_late_console_init);
875
876#else
877#define ATMEL_CONSOLE_DEVICE	NULL
878#endif
879
880static struct uart_driver atmel_uart = {
881	.owner			= THIS_MODULE,
882	.driver_name		= "atmel_serial",
883	.dev_name		= ATMEL_DEVICENAME,
884	.major			= SERIAL_ATMEL_MAJOR,
885	.minor			= MINOR_START,
886	.nr			= ATMEL_MAX_UART,
887	.cons			= ATMEL_CONSOLE_DEVICE,
888};
889
890#ifdef CONFIG_PM
891static int atmel_serial_suspend(struct platform_device *pdev, pm_message_t state)
892{
893	struct uart_port *port = platform_get_drvdata(pdev);
894	struct atmel_uart_port *atmel_port = (struct atmel_uart_port *) port;
895
896	if (device_may_wakeup(&pdev->dev) && !at91_suspend_entering_slow_clock())
897		enable_irq_wake(port->irq);
898	else {
899		uart_suspend_port(&atmel_uart, port);
900		atmel_port->suspended = 1;
901	}
902
903	return 0;
904}
905
906static int atmel_serial_resume(struct platform_device *pdev)
907{
908	struct uart_port *port = platform_get_drvdata(pdev);
909	struct atmel_uart_port *atmel_port = (struct atmel_uart_port *) port;
910
911	if (atmel_port->suspended) {
912		uart_resume_port(&atmel_uart, port);
913		atmel_port->suspended = 0;
914	}
915	else
916		disable_irq_wake(port->irq);
917
918	return 0;
919}
920#else
921#define atmel_serial_suspend NULL
922#define atmel_serial_resume NULL
923#endif
924
925static int __devinit atmel_serial_probe(struct platform_device *pdev)
926{
927	struct atmel_uart_port *port;
928	int ret;
929
930	port = &atmel_ports[pdev->id];
931	atmel_init_port(port, pdev);
932
933	ret = uart_add_one_port(&atmel_uart, &port->uart);
934	if (!ret) {
935		device_init_wakeup(&pdev->dev, 1);
936		platform_set_drvdata(pdev, port);
937	}
938
939	return ret;
940}
941
942static int __devexit atmel_serial_remove(struct platform_device *pdev)
943{
944	struct uart_port *port = platform_get_drvdata(pdev);
945	struct atmel_uart_port *atmel_port = (struct atmel_uart_port *) port;
946	int ret = 0;
947
948	clk_disable(atmel_port->clk);
949	clk_put(atmel_port->clk);
950
951	device_init_wakeup(&pdev->dev, 0);
952	platform_set_drvdata(pdev, NULL);
953
954	if (port) {
955		ret = uart_remove_one_port(&atmel_uart, port);
956		kfree(port);
957	}
958
959	return ret;
960}
961
962static struct platform_driver atmel_serial_driver = {
963	.probe		= atmel_serial_probe,
964	.remove		= __devexit_p(atmel_serial_remove),
965	.suspend	= atmel_serial_suspend,
966	.resume		= atmel_serial_resume,
967	.driver		= {
968		.name	= "atmel_usart",
969		.owner	= THIS_MODULE,
970	},
971};
972
973static int __init atmel_serial_init(void)
974{
975	int ret;
976
977	ret = uart_register_driver(&atmel_uart);
978	if (ret)
979		return ret;
980
981	ret = platform_driver_register(&atmel_serial_driver);
982	if (ret)
983		uart_unregister_driver(&atmel_uart);
984
985	return ret;
986}
987
988static void __exit atmel_serial_exit(void)
989{
990	platform_driver_unregister(&atmel_serial_driver);
991	uart_unregister_driver(&atmel_uart);
992}
993
994module_init(atmel_serial_init);
995module_exit(atmel_serial_exit);
996
997MODULE_AUTHOR("Rick Bronson");
998MODULE_DESCRIPTION("Atmel AT91 / AT32 serial port driver");
999MODULE_LICENSE("GPL");
1000