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v3.1
  1/*
  2 * uartlite.c: Serial driver for Xilinx uartlite serial controller
  3 *
  4 * Copyright (C) 2006 Peter Korsgaard <jacmet@sunsite.dk>
  5 * Copyright (C) 2007 Secret Lab Technologies Ltd.
  6 *
  7 * This file is licensed under the terms of the GNU General Public License
  8 * version 2.  This program is licensed "as is" without any warranty of any
  9 * kind, whether express or implied.
 10 */
 11
 12#include <linux/platform_device.h>
 13#include <linux/module.h>
 14#include <linux/console.h>
 15#include <linux/serial.h>
 16#include <linux/serial_core.h>
 17#include <linux/tty.h>
 
 18#include <linux/delay.h>
 19#include <linux/interrupt.h>
 20#include <linux/init.h>
 21#include <asm/io.h>
 22#include <linux/of.h>
 23#include <linux/of_address.h>
 24#include <linux/of_device.h>
 25#include <linux/of_platform.h>
 26
 27#define ULITE_NAME		"ttyUL"
 28#define ULITE_MAJOR		204
 29#define ULITE_MINOR		187
 30#define ULITE_NR_UARTS		4
 31
 32/* ---------------------------------------------------------------------
 33 * Register definitions
 34 *
 35 * For register details see datasheet:
 36 * http://www.xilinx.com/support/documentation/ip_documentation/opb_uartlite.pdf 
 37 */
 38
 39#define ULITE_RX		0x00
 40#define ULITE_TX		0x04
 41#define ULITE_STATUS		0x08
 42#define ULITE_CONTROL		0x0c
 43
 44#define ULITE_REGION		16
 45
 46#define ULITE_STATUS_RXVALID	0x01
 47#define ULITE_STATUS_RXFULL	0x02
 48#define ULITE_STATUS_TXEMPTY	0x04
 49#define ULITE_STATUS_TXFULL	0x08
 50#define ULITE_STATUS_IE		0x10
 51#define ULITE_STATUS_OVERRUN	0x20
 52#define ULITE_STATUS_FRAME	0x40
 53#define ULITE_STATUS_PARITY	0x80
 54
 55#define ULITE_CONTROL_RST_TX	0x01
 56#define ULITE_CONTROL_RST_RX	0x02
 57#define ULITE_CONTROL_IE	0x10
 58
 59
 60static struct uart_port ulite_ports[ULITE_NR_UARTS];
 61
 62/* ---------------------------------------------------------------------
 63 * Core UART driver operations
 64 */
 65
 66static int ulite_receive(struct uart_port *port, int stat)
 67{
 68	struct tty_struct *tty = port->state->port.tty;
 69	unsigned char ch = 0;
 70	char flag = TTY_NORMAL;
 71
 72	if ((stat & (ULITE_STATUS_RXVALID | ULITE_STATUS_OVERRUN
 73		     | ULITE_STATUS_FRAME)) == 0)
 74		return 0;
 75
 76	/* stats */
 77	if (stat & ULITE_STATUS_RXVALID) {
 78		port->icount.rx++;
 79		ch = ioread32be(port->membase + ULITE_RX);
 80
 81		if (stat & ULITE_STATUS_PARITY)
 82			port->icount.parity++;
 83	}
 84
 85	if (stat & ULITE_STATUS_OVERRUN)
 86		port->icount.overrun++;
 87
 88	if (stat & ULITE_STATUS_FRAME)
 89		port->icount.frame++;
 90
 91
 92	/* drop byte with parity error if IGNPAR specificed */
 93	if (stat & port->ignore_status_mask & ULITE_STATUS_PARITY)
 94		stat &= ~ULITE_STATUS_RXVALID;
 95
 96	stat &= port->read_status_mask;
 97
 98	if (stat & ULITE_STATUS_PARITY)
 99		flag = TTY_PARITY;
100
101
102	stat &= ~port->ignore_status_mask;
103
104	if (stat & ULITE_STATUS_RXVALID)
105		tty_insert_flip_char(tty, ch, flag);
106
107	if (stat & ULITE_STATUS_FRAME)
108		tty_insert_flip_char(tty, 0, TTY_FRAME);
109
110	if (stat & ULITE_STATUS_OVERRUN)
111		tty_insert_flip_char(tty, 0, TTY_OVERRUN);
112
113	return 1;
114}
115
116static int ulite_transmit(struct uart_port *port, int stat)
117{
118	struct circ_buf *xmit  = &port->state->xmit;
119
120	if (stat & ULITE_STATUS_TXFULL)
121		return 0;
122
123	if (port->x_char) {
124		iowrite32be(port->x_char, port->membase + ULITE_TX);
125		port->x_char = 0;
126		port->icount.tx++;
127		return 1;
128	}
129
130	if (uart_circ_empty(xmit) || uart_tx_stopped(port))
131		return 0;
132
133	iowrite32be(xmit->buf[xmit->tail], port->membase + ULITE_TX);
134	xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE-1);
135	port->icount.tx++;
136
137	/* wake up */
138	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
139		uart_write_wakeup(port);
140
141	return 1;
142}
143
144static irqreturn_t ulite_isr(int irq, void *dev_id)
145{
146	struct uart_port *port = dev_id;
147	int busy, n = 0;
148
149	do {
150		int stat = ioread32be(port->membase + ULITE_STATUS);
151		busy  = ulite_receive(port, stat);
152		busy |= ulite_transmit(port, stat);
153		n++;
154	} while (busy);
155
156	/* work done? */
157	if (n > 1) {
158		tty_flip_buffer_push(port->state->port.tty);
159		return IRQ_HANDLED;
160	} else {
161		return IRQ_NONE;
162	}
163}
164
165static unsigned int ulite_tx_empty(struct uart_port *port)
166{
167	unsigned long flags;
168	unsigned int ret;
169
170	spin_lock_irqsave(&port->lock, flags);
171	ret = ioread32be(port->membase + ULITE_STATUS);
172	spin_unlock_irqrestore(&port->lock, flags);
173
174	return ret & ULITE_STATUS_TXEMPTY ? TIOCSER_TEMT : 0;
175}
176
177static unsigned int ulite_get_mctrl(struct uart_port *port)
178{
179	return TIOCM_CTS | TIOCM_DSR | TIOCM_CAR;
180}
181
182static void ulite_set_mctrl(struct uart_port *port, unsigned int mctrl)
183{
184	/* N/A */
185}
186
187static void ulite_stop_tx(struct uart_port *port)
188{
189	/* N/A */
190}
191
192static void ulite_start_tx(struct uart_port *port)
193{
194	ulite_transmit(port, ioread32be(port->membase + ULITE_STATUS));
195}
196
197static void ulite_stop_rx(struct uart_port *port)
198{
199	/* don't forward any more data (like !CREAD) */
200	port->ignore_status_mask = ULITE_STATUS_RXVALID | ULITE_STATUS_PARITY
201		| ULITE_STATUS_FRAME | ULITE_STATUS_OVERRUN;
202}
203
204static void ulite_enable_ms(struct uart_port *port)
205{
206	/* N/A */
207}
208
209static void ulite_break_ctl(struct uart_port *port, int ctl)
210{
211	/* N/A */
212}
213
214static int ulite_startup(struct uart_port *port)
215{
216	int ret;
217
218	ret = request_irq(port->irq, ulite_isr,
219			  IRQF_SHARED | IRQF_SAMPLE_RANDOM, "uartlite", port);
220	if (ret)
221		return ret;
222
223	iowrite32be(ULITE_CONTROL_RST_RX | ULITE_CONTROL_RST_TX,
224	       port->membase + ULITE_CONTROL);
225	iowrite32be(ULITE_CONTROL_IE, port->membase + ULITE_CONTROL);
226
227	return 0;
228}
229
230static void ulite_shutdown(struct uart_port *port)
231{
232	iowrite32be(0, port->membase + ULITE_CONTROL);
233	ioread32be(port->membase + ULITE_CONTROL); /* dummy */
234	free_irq(port->irq, port);
235}
236
237static void ulite_set_termios(struct uart_port *port, struct ktermios *termios,
238			      struct ktermios *old)
239{
240	unsigned long flags;
241	unsigned int baud;
242
243	spin_lock_irqsave(&port->lock, flags);
244
245	port->read_status_mask = ULITE_STATUS_RXVALID | ULITE_STATUS_OVERRUN
246		| ULITE_STATUS_TXFULL;
247
248	if (termios->c_iflag & INPCK)
249		port->read_status_mask |=
250			ULITE_STATUS_PARITY | ULITE_STATUS_FRAME;
251
252	port->ignore_status_mask = 0;
253	if (termios->c_iflag & IGNPAR)
254		port->ignore_status_mask |= ULITE_STATUS_PARITY
255			| ULITE_STATUS_FRAME | ULITE_STATUS_OVERRUN;
256
257	/* ignore all characters if CREAD is not set */
258	if ((termios->c_cflag & CREAD) == 0)
259		port->ignore_status_mask |=
260			ULITE_STATUS_RXVALID | ULITE_STATUS_PARITY
261			| ULITE_STATUS_FRAME | ULITE_STATUS_OVERRUN;
262
263	/* update timeout */
264	baud = uart_get_baud_rate(port, termios, old, 0, 460800);
265	uart_update_timeout(port, termios->c_cflag, baud);
266
267	spin_unlock_irqrestore(&port->lock, flags);
268}
269
270static const char *ulite_type(struct uart_port *port)
271{
272	return port->type == PORT_UARTLITE ? "uartlite" : NULL;
273}
274
275static void ulite_release_port(struct uart_port *port)
276{
277	release_mem_region(port->mapbase, ULITE_REGION);
278	iounmap(port->membase);
279	port->membase = NULL;
280}
281
282static int ulite_request_port(struct uart_port *port)
283{
284	pr_debug("ulite console: port=%p; port->mapbase=%llx\n",
285		 port, (unsigned long long) port->mapbase);
286
287	if (!request_mem_region(port->mapbase, ULITE_REGION, "uartlite")) {
288		dev_err(port->dev, "Memory region busy\n");
289		return -EBUSY;
290	}
291
292	port->membase = ioremap(port->mapbase, ULITE_REGION);
293	if (!port->membase) {
294		dev_err(port->dev, "Unable to map registers\n");
295		release_mem_region(port->mapbase, ULITE_REGION);
296		return -EBUSY;
297	}
298
299	return 0;
300}
301
302static void ulite_config_port(struct uart_port *port, int flags)
303{
304	if (!ulite_request_port(port))
305		port->type = PORT_UARTLITE;
306}
307
308static int ulite_verify_port(struct uart_port *port, struct serial_struct *ser)
309{
310	/* we don't want the core code to modify any port params */
311	return -EINVAL;
312}
313
314#ifdef CONFIG_CONSOLE_POLL
315static int ulite_get_poll_char(struct uart_port *port)
316{
317	if (!(ioread32be(port->membase + ULITE_STATUS)
318						& ULITE_STATUS_RXVALID))
319		return NO_POLL_CHAR;
320
321	return ioread32be(port->membase + ULITE_RX);
322}
323
324static void ulite_put_poll_char(struct uart_port *port, unsigned char ch)
325{
326	while (ioread32be(port->membase + ULITE_STATUS) & ULITE_STATUS_TXFULL)
327		cpu_relax();
328
329	/* write char to device */
330	iowrite32be(ch, port->membase + ULITE_TX);
331}
332#endif
333
334static struct uart_ops ulite_ops = {
335	.tx_empty	= ulite_tx_empty,
336	.set_mctrl	= ulite_set_mctrl,
337	.get_mctrl	= ulite_get_mctrl,
338	.stop_tx	= ulite_stop_tx,
339	.start_tx	= ulite_start_tx,
340	.stop_rx	= ulite_stop_rx,
341	.enable_ms	= ulite_enable_ms,
342	.break_ctl	= ulite_break_ctl,
343	.startup	= ulite_startup,
344	.shutdown	= ulite_shutdown,
345	.set_termios	= ulite_set_termios,
346	.type		= ulite_type,
347	.release_port	= ulite_release_port,
348	.request_port	= ulite_request_port,
349	.config_port	= ulite_config_port,
350	.verify_port	= ulite_verify_port,
351#ifdef CONFIG_CONSOLE_POLL
352	.poll_get_char	= ulite_get_poll_char,
353	.poll_put_char	= ulite_put_poll_char,
354#endif
355};
356
357/* ---------------------------------------------------------------------
358 * Console driver operations
359 */
360
361#ifdef CONFIG_SERIAL_UARTLITE_CONSOLE
362static void ulite_console_wait_tx(struct uart_port *port)
363{
364	int i;
365	u8 val;
366
367	/* Spin waiting for TX fifo to have space available */
368	for (i = 0; i < 100000; i++) {
369		val = ioread32be(port->membase + ULITE_STATUS);
370		if ((val & ULITE_STATUS_TXFULL) == 0)
371			break;
372		cpu_relax();
373	}
374}
375
376static void ulite_console_putchar(struct uart_port *port, int ch)
377{
378	ulite_console_wait_tx(port);
379	iowrite32be(ch, port->membase + ULITE_TX);
380}
381
382static void ulite_console_write(struct console *co, const char *s,
383				unsigned int count)
384{
385	struct uart_port *port = &ulite_ports[co->index];
386	unsigned long flags;
387	unsigned int ier;
388	int locked = 1;
389
390	if (oops_in_progress) {
391		locked = spin_trylock_irqsave(&port->lock, flags);
392	} else
393		spin_lock_irqsave(&port->lock, flags);
394
395	/* save and disable interrupt */
396	ier = ioread32be(port->membase + ULITE_STATUS) & ULITE_STATUS_IE;
397	iowrite32be(0, port->membase + ULITE_CONTROL);
398
399	uart_console_write(port, s, count, ulite_console_putchar);
400
401	ulite_console_wait_tx(port);
402
403	/* restore interrupt state */
404	if (ier)
405		iowrite32be(ULITE_CONTROL_IE, port->membase + ULITE_CONTROL);
406
407	if (locked)
408		spin_unlock_irqrestore(&port->lock, flags);
409}
410
411static int __devinit ulite_console_setup(struct console *co, char *options)
412{
413	struct uart_port *port;
414	int baud = 9600;
415	int bits = 8;
416	int parity = 'n';
417	int flow = 'n';
418
419	if (co->index < 0 || co->index >= ULITE_NR_UARTS)
420		return -EINVAL;
421
422	port = &ulite_ports[co->index];
423
424	/* Has the device been initialized yet? */
425	if (!port->mapbase) {
426		pr_debug("console on ttyUL%i not present\n", co->index);
427		return -ENODEV;
428	}
429
430	/* not initialized yet? */
431	if (!port->membase) {
432		if (ulite_request_port(port))
433			return -ENODEV;
434	}
435
436	if (options)
437		uart_parse_options(options, &baud, &parity, &bits, &flow);
438
439	return uart_set_options(port, co, baud, parity, bits, flow);
440}
441
442static struct uart_driver ulite_uart_driver;
443
444static struct console ulite_console = {
445	.name	= ULITE_NAME,
446	.write	= ulite_console_write,
447	.device	= uart_console_device,
448	.setup	= ulite_console_setup,
449	.flags	= CON_PRINTBUFFER,
450	.index	= -1, /* Specified on the cmdline (e.g. console=ttyUL0 ) */
451	.data	= &ulite_uart_driver,
452};
453
454static int __init ulite_console_init(void)
455{
456	register_console(&ulite_console);
457	return 0;
458}
459
460console_initcall(ulite_console_init);
461
462#endif /* CONFIG_SERIAL_UARTLITE_CONSOLE */
463
464static struct uart_driver ulite_uart_driver = {
465	.owner		= THIS_MODULE,
466	.driver_name	= "uartlite",
467	.dev_name	= ULITE_NAME,
468	.major		= ULITE_MAJOR,
469	.minor		= ULITE_MINOR,
470	.nr		= ULITE_NR_UARTS,
471#ifdef CONFIG_SERIAL_UARTLITE_CONSOLE
472	.cons		= &ulite_console,
473#endif
474};
475
476/* ---------------------------------------------------------------------
477 * Port assignment functions (mapping devices to uart_port structures)
478 */
479
480/** ulite_assign: register a uartlite device with the driver
481 *
482 * @dev: pointer to device structure
483 * @id: requested id number.  Pass -1 for automatic port assignment
484 * @base: base address of uartlite registers
485 * @irq: irq number for uartlite
486 *
487 * Returns: 0 on success, <0 otherwise
488 */
489static int __devinit ulite_assign(struct device *dev, int id, u32 base, int irq)
490{
491	struct uart_port *port;
492	int rc;
493
494	/* if id = -1; then scan for a free id and use that */
495	if (id < 0) {
496		for (id = 0; id < ULITE_NR_UARTS; id++)
497			if (ulite_ports[id].mapbase == 0)
498				break;
499	}
500	if (id < 0 || id >= ULITE_NR_UARTS) {
501		dev_err(dev, "%s%i too large\n", ULITE_NAME, id);
502		return -EINVAL;
503	}
504
505	if ((ulite_ports[id].mapbase) && (ulite_ports[id].mapbase != base)) {
506		dev_err(dev, "cannot assign to %s%i; it is already in use\n",
507			ULITE_NAME, id);
508		return -EBUSY;
509	}
510
511	port = &ulite_ports[id];
512
513	spin_lock_init(&port->lock);
514	port->fifosize = 16;
515	port->regshift = 2;
516	port->iotype = UPIO_MEM;
517	port->iobase = 1; /* mark port in use */
518	port->mapbase = base;
519	port->membase = NULL;
520	port->ops = &ulite_ops;
521	port->irq = irq;
522	port->flags = UPF_BOOT_AUTOCONF;
523	port->dev = dev;
524	port->type = PORT_UNKNOWN;
525	port->line = id;
526
527	dev_set_drvdata(dev, port);
528
529	/* Register the port */
530	rc = uart_add_one_port(&ulite_uart_driver, port);
531	if (rc) {
532		dev_err(dev, "uart_add_one_port() failed; err=%i\n", rc);
533		port->mapbase = 0;
534		dev_set_drvdata(dev, NULL);
535		return rc;
536	}
537
538	return 0;
539}
540
541/** ulite_release: register a uartlite device with the driver
542 *
543 * @dev: pointer to device structure
544 */
545static int __devexit ulite_release(struct device *dev)
546{
547	struct uart_port *port = dev_get_drvdata(dev);
548	int rc = 0;
549
550	if (port) {
551		rc = uart_remove_one_port(&ulite_uart_driver, port);
552		dev_set_drvdata(dev, NULL);
553		port->mapbase = 0;
554	}
555
556	return rc;
557}
558
559/* ---------------------------------------------------------------------
560 * Platform bus binding
561 */
562
563#if defined(CONFIG_OF)
564/* Match table for of_platform binding */
565static struct of_device_id ulite_of_match[] __devinitdata = {
566	{ .compatible = "xlnx,opb-uartlite-1.00.b", },
567	{ .compatible = "xlnx,xps-uartlite-1.00.a", },
568	{}
569};
570MODULE_DEVICE_TABLE(of, ulite_of_match);
571#else /* CONFIG_OF */
572#define ulite_of_match NULL
573#endif /* CONFIG_OF */
574
575static int __devinit ulite_probe(struct platform_device *pdev)
576{
577	struct resource *res, *res2;
578	int id = pdev->id;
579#ifdef CONFIG_OF
580	const __be32 *prop;
581
582	prop = of_get_property(pdev->dev.of_node, "port-number", NULL);
583	if (prop)
584		id = be32_to_cpup(prop);
585#endif
586
587	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
588	if (!res)
589		return -ENODEV;
590
591	res2 = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
592	if (!res2)
593		return -ENODEV;
594
595	return ulite_assign(&pdev->dev, id, res->start, res2->start);
596}
597
598static int __devexit ulite_remove(struct platform_device *pdev)
599{
600	return ulite_release(&pdev->dev);
601}
602
603/* work with hotplug and coldplug */
604MODULE_ALIAS("platform:uartlite");
605
606static struct platform_driver ulite_platform_driver = {
607	.probe = ulite_probe,
608	.remove = __devexit_p(ulite_remove),
609	.driver = {
610		.owner = THIS_MODULE,
611		.name  = "uartlite",
612		.of_match_table = ulite_of_match,
613	},
614};
615
616/* ---------------------------------------------------------------------
617 * Module setup/teardown
618 */
619
620int __init ulite_init(void)
621{
622	int ret;
623
624	pr_debug("uartlite: calling uart_register_driver()\n");
625	ret = uart_register_driver(&ulite_uart_driver);
626	if (ret)
627		goto err_uart;
628
629	pr_debug("uartlite: calling platform_driver_register()\n");
630	ret = platform_driver_register(&ulite_platform_driver);
631	if (ret)
632		goto err_plat;
633
634	return 0;
635
636err_plat:
637	uart_unregister_driver(&ulite_uart_driver);
638err_uart:
639	printk(KERN_ERR "registering uartlite driver failed: err=%i", ret);
640	return ret;
641}
642
643void __exit ulite_exit(void)
644{
645	platform_driver_unregister(&ulite_platform_driver);
646	uart_unregister_driver(&ulite_uart_driver);
647}
648
649module_init(ulite_init);
650module_exit(ulite_exit);
651
652MODULE_AUTHOR("Peter Korsgaard <jacmet@sunsite.dk>");
653MODULE_DESCRIPTION("Xilinx uartlite serial driver");
654MODULE_LICENSE("GPL");
v3.5.6
  1/*
  2 * uartlite.c: Serial driver for Xilinx uartlite serial controller
  3 *
  4 * Copyright (C) 2006 Peter Korsgaard <jacmet@sunsite.dk>
  5 * Copyright (C) 2007 Secret Lab Technologies Ltd.
  6 *
  7 * This file is licensed under the terms of the GNU General Public License
  8 * version 2.  This program is licensed "as is" without any warranty of any
  9 * kind, whether express or implied.
 10 */
 11
 12#include <linux/platform_device.h>
 13#include <linux/module.h>
 14#include <linux/console.h>
 15#include <linux/serial.h>
 16#include <linux/serial_core.h>
 17#include <linux/tty.h>
 18#include <linux/tty_flip.h>
 19#include <linux/delay.h>
 20#include <linux/interrupt.h>
 21#include <linux/init.h>
 22#include <asm/io.h>
 23#include <linux/of.h>
 24#include <linux/of_address.h>
 25#include <linux/of_device.h>
 26#include <linux/of_platform.h>
 27
 28#define ULITE_NAME		"ttyUL"
 29#define ULITE_MAJOR		204
 30#define ULITE_MINOR		187
 31#define ULITE_NR_UARTS		4
 32
 33/* ---------------------------------------------------------------------
 34 * Register definitions
 35 *
 36 * For register details see datasheet:
 37 * http://www.xilinx.com/support/documentation/ip_documentation/opb_uartlite.pdf 
 38 */
 39
 40#define ULITE_RX		0x00
 41#define ULITE_TX		0x04
 42#define ULITE_STATUS		0x08
 43#define ULITE_CONTROL		0x0c
 44
 45#define ULITE_REGION		16
 46
 47#define ULITE_STATUS_RXVALID	0x01
 48#define ULITE_STATUS_RXFULL	0x02
 49#define ULITE_STATUS_TXEMPTY	0x04
 50#define ULITE_STATUS_TXFULL	0x08
 51#define ULITE_STATUS_IE		0x10
 52#define ULITE_STATUS_OVERRUN	0x20
 53#define ULITE_STATUS_FRAME	0x40
 54#define ULITE_STATUS_PARITY	0x80
 55
 56#define ULITE_CONTROL_RST_TX	0x01
 57#define ULITE_CONTROL_RST_RX	0x02
 58#define ULITE_CONTROL_IE	0x10
 59
 60
 61static struct uart_port ulite_ports[ULITE_NR_UARTS];
 62
 63/* ---------------------------------------------------------------------
 64 * Core UART driver operations
 65 */
 66
 67static int ulite_receive(struct uart_port *port, int stat)
 68{
 69	struct tty_struct *tty = port->state->port.tty;
 70	unsigned char ch = 0;
 71	char flag = TTY_NORMAL;
 72
 73	if ((stat & (ULITE_STATUS_RXVALID | ULITE_STATUS_OVERRUN
 74		     | ULITE_STATUS_FRAME)) == 0)
 75		return 0;
 76
 77	/* stats */
 78	if (stat & ULITE_STATUS_RXVALID) {
 79		port->icount.rx++;
 80		ch = ioread32be(port->membase + ULITE_RX);
 81
 82		if (stat & ULITE_STATUS_PARITY)
 83			port->icount.parity++;
 84	}
 85
 86	if (stat & ULITE_STATUS_OVERRUN)
 87		port->icount.overrun++;
 88
 89	if (stat & ULITE_STATUS_FRAME)
 90		port->icount.frame++;
 91
 92
 93	/* drop byte with parity error if IGNPAR specificed */
 94	if (stat & port->ignore_status_mask & ULITE_STATUS_PARITY)
 95		stat &= ~ULITE_STATUS_RXVALID;
 96
 97	stat &= port->read_status_mask;
 98
 99	if (stat & ULITE_STATUS_PARITY)
100		flag = TTY_PARITY;
101
102
103	stat &= ~port->ignore_status_mask;
104
105	if (stat & ULITE_STATUS_RXVALID)
106		tty_insert_flip_char(tty, ch, flag);
107
108	if (stat & ULITE_STATUS_FRAME)
109		tty_insert_flip_char(tty, 0, TTY_FRAME);
110
111	if (stat & ULITE_STATUS_OVERRUN)
112		tty_insert_flip_char(tty, 0, TTY_OVERRUN);
113
114	return 1;
115}
116
117static int ulite_transmit(struct uart_port *port, int stat)
118{
119	struct circ_buf *xmit  = &port->state->xmit;
120
121	if (stat & ULITE_STATUS_TXFULL)
122		return 0;
123
124	if (port->x_char) {
125		iowrite32be(port->x_char, port->membase + ULITE_TX);
126		port->x_char = 0;
127		port->icount.tx++;
128		return 1;
129	}
130
131	if (uart_circ_empty(xmit) || uart_tx_stopped(port))
132		return 0;
133
134	iowrite32be(xmit->buf[xmit->tail], port->membase + ULITE_TX);
135	xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE-1);
136	port->icount.tx++;
137
138	/* wake up */
139	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
140		uart_write_wakeup(port);
141
142	return 1;
143}
144
145static irqreturn_t ulite_isr(int irq, void *dev_id)
146{
147	struct uart_port *port = dev_id;
148	int busy, n = 0;
149
150	do {
151		int stat = ioread32be(port->membase + ULITE_STATUS);
152		busy  = ulite_receive(port, stat);
153		busy |= ulite_transmit(port, stat);
154		n++;
155	} while (busy);
156
157	/* work done? */
158	if (n > 1) {
159		tty_flip_buffer_push(port->state->port.tty);
160		return IRQ_HANDLED;
161	} else {
162		return IRQ_NONE;
163	}
164}
165
166static unsigned int ulite_tx_empty(struct uart_port *port)
167{
168	unsigned long flags;
169	unsigned int ret;
170
171	spin_lock_irqsave(&port->lock, flags);
172	ret = ioread32be(port->membase + ULITE_STATUS);
173	spin_unlock_irqrestore(&port->lock, flags);
174
175	return ret & ULITE_STATUS_TXEMPTY ? TIOCSER_TEMT : 0;
176}
177
178static unsigned int ulite_get_mctrl(struct uart_port *port)
179{
180	return TIOCM_CTS | TIOCM_DSR | TIOCM_CAR;
181}
182
183static void ulite_set_mctrl(struct uart_port *port, unsigned int mctrl)
184{
185	/* N/A */
186}
187
188static void ulite_stop_tx(struct uart_port *port)
189{
190	/* N/A */
191}
192
193static void ulite_start_tx(struct uart_port *port)
194{
195	ulite_transmit(port, ioread32be(port->membase + ULITE_STATUS));
196}
197
198static void ulite_stop_rx(struct uart_port *port)
199{
200	/* don't forward any more data (like !CREAD) */
201	port->ignore_status_mask = ULITE_STATUS_RXVALID | ULITE_STATUS_PARITY
202		| ULITE_STATUS_FRAME | ULITE_STATUS_OVERRUN;
203}
204
205static void ulite_enable_ms(struct uart_port *port)
206{
207	/* N/A */
208}
209
210static void ulite_break_ctl(struct uart_port *port, int ctl)
211{
212	/* N/A */
213}
214
215static int ulite_startup(struct uart_port *port)
216{
217	int ret;
218
219	ret = request_irq(port->irq, ulite_isr,
220			  IRQF_SHARED | IRQF_SAMPLE_RANDOM, "uartlite", port);
221	if (ret)
222		return ret;
223
224	iowrite32be(ULITE_CONTROL_RST_RX | ULITE_CONTROL_RST_TX,
225	       port->membase + ULITE_CONTROL);
226	iowrite32be(ULITE_CONTROL_IE, port->membase + ULITE_CONTROL);
227
228	return 0;
229}
230
231static void ulite_shutdown(struct uart_port *port)
232{
233	iowrite32be(0, port->membase + ULITE_CONTROL);
234	ioread32be(port->membase + ULITE_CONTROL); /* dummy */
235	free_irq(port->irq, port);
236}
237
238static void ulite_set_termios(struct uart_port *port, struct ktermios *termios,
239			      struct ktermios *old)
240{
241	unsigned long flags;
242	unsigned int baud;
243
244	spin_lock_irqsave(&port->lock, flags);
245
246	port->read_status_mask = ULITE_STATUS_RXVALID | ULITE_STATUS_OVERRUN
247		| ULITE_STATUS_TXFULL;
248
249	if (termios->c_iflag & INPCK)
250		port->read_status_mask |=
251			ULITE_STATUS_PARITY | ULITE_STATUS_FRAME;
252
253	port->ignore_status_mask = 0;
254	if (termios->c_iflag & IGNPAR)
255		port->ignore_status_mask |= ULITE_STATUS_PARITY
256			| ULITE_STATUS_FRAME | ULITE_STATUS_OVERRUN;
257
258	/* ignore all characters if CREAD is not set */
259	if ((termios->c_cflag & CREAD) == 0)
260		port->ignore_status_mask |=
261			ULITE_STATUS_RXVALID | ULITE_STATUS_PARITY
262			| ULITE_STATUS_FRAME | ULITE_STATUS_OVERRUN;
263
264	/* update timeout */
265	baud = uart_get_baud_rate(port, termios, old, 0, 460800);
266	uart_update_timeout(port, termios->c_cflag, baud);
267
268	spin_unlock_irqrestore(&port->lock, flags);
269}
270
271static const char *ulite_type(struct uart_port *port)
272{
273	return port->type == PORT_UARTLITE ? "uartlite" : NULL;
274}
275
276static void ulite_release_port(struct uart_port *port)
277{
278	release_mem_region(port->mapbase, ULITE_REGION);
279	iounmap(port->membase);
280	port->membase = NULL;
281}
282
283static int ulite_request_port(struct uart_port *port)
284{
285	pr_debug("ulite console: port=%p; port->mapbase=%llx\n",
286		 port, (unsigned long long) port->mapbase);
287
288	if (!request_mem_region(port->mapbase, ULITE_REGION, "uartlite")) {
289		dev_err(port->dev, "Memory region busy\n");
290		return -EBUSY;
291	}
292
293	port->membase = ioremap(port->mapbase, ULITE_REGION);
294	if (!port->membase) {
295		dev_err(port->dev, "Unable to map registers\n");
296		release_mem_region(port->mapbase, ULITE_REGION);
297		return -EBUSY;
298	}
299
300	return 0;
301}
302
303static void ulite_config_port(struct uart_port *port, int flags)
304{
305	if (!ulite_request_port(port))
306		port->type = PORT_UARTLITE;
307}
308
309static int ulite_verify_port(struct uart_port *port, struct serial_struct *ser)
310{
311	/* we don't want the core code to modify any port params */
312	return -EINVAL;
313}
314
315#ifdef CONFIG_CONSOLE_POLL
316static int ulite_get_poll_char(struct uart_port *port)
317{
318	if (!(ioread32be(port->membase + ULITE_STATUS)
319						& ULITE_STATUS_RXVALID))
320		return NO_POLL_CHAR;
321
322	return ioread32be(port->membase + ULITE_RX);
323}
324
325static void ulite_put_poll_char(struct uart_port *port, unsigned char ch)
326{
327	while (ioread32be(port->membase + ULITE_STATUS) & ULITE_STATUS_TXFULL)
328		cpu_relax();
329
330	/* write char to device */
331	iowrite32be(ch, port->membase + ULITE_TX);
332}
333#endif
334
335static struct uart_ops ulite_ops = {
336	.tx_empty	= ulite_tx_empty,
337	.set_mctrl	= ulite_set_mctrl,
338	.get_mctrl	= ulite_get_mctrl,
339	.stop_tx	= ulite_stop_tx,
340	.start_tx	= ulite_start_tx,
341	.stop_rx	= ulite_stop_rx,
342	.enable_ms	= ulite_enable_ms,
343	.break_ctl	= ulite_break_ctl,
344	.startup	= ulite_startup,
345	.shutdown	= ulite_shutdown,
346	.set_termios	= ulite_set_termios,
347	.type		= ulite_type,
348	.release_port	= ulite_release_port,
349	.request_port	= ulite_request_port,
350	.config_port	= ulite_config_port,
351	.verify_port	= ulite_verify_port,
352#ifdef CONFIG_CONSOLE_POLL
353	.poll_get_char	= ulite_get_poll_char,
354	.poll_put_char	= ulite_put_poll_char,
355#endif
356};
357
358/* ---------------------------------------------------------------------
359 * Console driver operations
360 */
361
362#ifdef CONFIG_SERIAL_UARTLITE_CONSOLE
363static void ulite_console_wait_tx(struct uart_port *port)
364{
365	int i;
366	u8 val;
367
368	/* Spin waiting for TX fifo to have space available */
369	for (i = 0; i < 100000; i++) {
370		val = ioread32be(port->membase + ULITE_STATUS);
371		if ((val & ULITE_STATUS_TXFULL) == 0)
372			break;
373		cpu_relax();
374	}
375}
376
377static void ulite_console_putchar(struct uart_port *port, int ch)
378{
379	ulite_console_wait_tx(port);
380	iowrite32be(ch, port->membase + ULITE_TX);
381}
382
383static void ulite_console_write(struct console *co, const char *s,
384				unsigned int count)
385{
386	struct uart_port *port = &ulite_ports[co->index];
387	unsigned long flags;
388	unsigned int ier;
389	int locked = 1;
390
391	if (oops_in_progress) {
392		locked = spin_trylock_irqsave(&port->lock, flags);
393	} else
394		spin_lock_irqsave(&port->lock, flags);
395
396	/* save and disable interrupt */
397	ier = ioread32be(port->membase + ULITE_STATUS) & ULITE_STATUS_IE;
398	iowrite32be(0, port->membase + ULITE_CONTROL);
399
400	uart_console_write(port, s, count, ulite_console_putchar);
401
402	ulite_console_wait_tx(port);
403
404	/* restore interrupt state */
405	if (ier)
406		iowrite32be(ULITE_CONTROL_IE, port->membase + ULITE_CONTROL);
407
408	if (locked)
409		spin_unlock_irqrestore(&port->lock, flags);
410}
411
412static int __devinit ulite_console_setup(struct console *co, char *options)
413{
414	struct uart_port *port;
415	int baud = 9600;
416	int bits = 8;
417	int parity = 'n';
418	int flow = 'n';
419
420	if (co->index < 0 || co->index >= ULITE_NR_UARTS)
421		return -EINVAL;
422
423	port = &ulite_ports[co->index];
424
425	/* Has the device been initialized yet? */
426	if (!port->mapbase) {
427		pr_debug("console on ttyUL%i not present\n", co->index);
428		return -ENODEV;
429	}
430
431	/* not initialized yet? */
432	if (!port->membase) {
433		if (ulite_request_port(port))
434			return -ENODEV;
435	}
436
437	if (options)
438		uart_parse_options(options, &baud, &parity, &bits, &flow);
439
440	return uart_set_options(port, co, baud, parity, bits, flow);
441}
442
443static struct uart_driver ulite_uart_driver;
444
445static struct console ulite_console = {
446	.name	= ULITE_NAME,
447	.write	= ulite_console_write,
448	.device	= uart_console_device,
449	.setup	= ulite_console_setup,
450	.flags	= CON_PRINTBUFFER,
451	.index	= -1, /* Specified on the cmdline (e.g. console=ttyUL0 ) */
452	.data	= &ulite_uart_driver,
453};
454
455static int __init ulite_console_init(void)
456{
457	register_console(&ulite_console);
458	return 0;
459}
460
461console_initcall(ulite_console_init);
462
463#endif /* CONFIG_SERIAL_UARTLITE_CONSOLE */
464
465static struct uart_driver ulite_uart_driver = {
466	.owner		= THIS_MODULE,
467	.driver_name	= "uartlite",
468	.dev_name	= ULITE_NAME,
469	.major		= ULITE_MAJOR,
470	.minor		= ULITE_MINOR,
471	.nr		= ULITE_NR_UARTS,
472#ifdef CONFIG_SERIAL_UARTLITE_CONSOLE
473	.cons		= &ulite_console,
474#endif
475};
476
477/* ---------------------------------------------------------------------
478 * Port assignment functions (mapping devices to uart_port structures)
479 */
480
481/** ulite_assign: register a uartlite device with the driver
482 *
483 * @dev: pointer to device structure
484 * @id: requested id number.  Pass -1 for automatic port assignment
485 * @base: base address of uartlite registers
486 * @irq: irq number for uartlite
487 *
488 * Returns: 0 on success, <0 otherwise
489 */
490static int __devinit ulite_assign(struct device *dev, int id, u32 base, int irq)
491{
492	struct uart_port *port;
493	int rc;
494
495	/* if id = -1; then scan for a free id and use that */
496	if (id < 0) {
497		for (id = 0; id < ULITE_NR_UARTS; id++)
498			if (ulite_ports[id].mapbase == 0)
499				break;
500	}
501	if (id < 0 || id >= ULITE_NR_UARTS) {
502		dev_err(dev, "%s%i too large\n", ULITE_NAME, id);
503		return -EINVAL;
504	}
505
506	if ((ulite_ports[id].mapbase) && (ulite_ports[id].mapbase != base)) {
507		dev_err(dev, "cannot assign to %s%i; it is already in use\n",
508			ULITE_NAME, id);
509		return -EBUSY;
510	}
511
512	port = &ulite_ports[id];
513
514	spin_lock_init(&port->lock);
515	port->fifosize = 16;
516	port->regshift = 2;
517	port->iotype = UPIO_MEM;
518	port->iobase = 1; /* mark port in use */
519	port->mapbase = base;
520	port->membase = NULL;
521	port->ops = &ulite_ops;
522	port->irq = irq;
523	port->flags = UPF_BOOT_AUTOCONF;
524	port->dev = dev;
525	port->type = PORT_UNKNOWN;
526	port->line = id;
527
528	dev_set_drvdata(dev, port);
529
530	/* Register the port */
531	rc = uart_add_one_port(&ulite_uart_driver, port);
532	if (rc) {
533		dev_err(dev, "uart_add_one_port() failed; err=%i\n", rc);
534		port->mapbase = 0;
535		dev_set_drvdata(dev, NULL);
536		return rc;
537	}
538
539	return 0;
540}
541
542/** ulite_release: register a uartlite device with the driver
543 *
544 * @dev: pointer to device structure
545 */
546static int __devexit ulite_release(struct device *dev)
547{
548	struct uart_port *port = dev_get_drvdata(dev);
549	int rc = 0;
550
551	if (port) {
552		rc = uart_remove_one_port(&ulite_uart_driver, port);
553		dev_set_drvdata(dev, NULL);
554		port->mapbase = 0;
555	}
556
557	return rc;
558}
559
560/* ---------------------------------------------------------------------
561 * Platform bus binding
562 */
563
564#if defined(CONFIG_OF)
565/* Match table for of_platform binding */
566static struct of_device_id ulite_of_match[] __devinitdata = {
567	{ .compatible = "xlnx,opb-uartlite-1.00.b", },
568	{ .compatible = "xlnx,xps-uartlite-1.00.a", },
569	{}
570};
571MODULE_DEVICE_TABLE(of, ulite_of_match);
 
 
572#endif /* CONFIG_OF */
573
574static int __devinit ulite_probe(struct platform_device *pdev)
575{
576	struct resource *res, *res2;
577	int id = pdev->id;
578#ifdef CONFIG_OF
579	const __be32 *prop;
580
581	prop = of_get_property(pdev->dev.of_node, "port-number", NULL);
582	if (prop)
583		id = be32_to_cpup(prop);
584#endif
585
586	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
587	if (!res)
588		return -ENODEV;
589
590	res2 = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
591	if (!res2)
592		return -ENODEV;
593
594	return ulite_assign(&pdev->dev, id, res->start, res2->start);
595}
596
597static int __devexit ulite_remove(struct platform_device *pdev)
598{
599	return ulite_release(&pdev->dev);
600}
601
602/* work with hotplug and coldplug */
603MODULE_ALIAS("platform:uartlite");
604
605static struct platform_driver ulite_platform_driver = {
606	.probe = ulite_probe,
607	.remove = __devexit_p(ulite_remove),
608	.driver = {
609		.owner = THIS_MODULE,
610		.name  = "uartlite",
611		.of_match_table = of_match_ptr(ulite_of_match),
612	},
613};
614
615/* ---------------------------------------------------------------------
616 * Module setup/teardown
617 */
618
619int __init ulite_init(void)
620{
621	int ret;
622
623	pr_debug("uartlite: calling uart_register_driver()\n");
624	ret = uart_register_driver(&ulite_uart_driver);
625	if (ret)
626		goto err_uart;
627
628	pr_debug("uartlite: calling platform_driver_register()\n");
629	ret = platform_driver_register(&ulite_platform_driver);
630	if (ret)
631		goto err_plat;
632
633	return 0;
634
635err_plat:
636	uart_unregister_driver(&ulite_uart_driver);
637err_uart:
638	printk(KERN_ERR "registering uartlite driver failed: err=%i", ret);
639	return ret;
640}
641
642void __exit ulite_exit(void)
643{
644	platform_driver_unregister(&ulite_platform_driver);
645	uart_unregister_driver(&ulite_uart_driver);
646}
647
648module_init(ulite_init);
649module_exit(ulite_exit);
650
651MODULE_AUTHOR("Peter Korsgaard <jacmet@sunsite.dk>");
652MODULE_DESCRIPTION("Xilinx uartlite serial driver");
653MODULE_LICENSE("GPL");