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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");
v6.2
  1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * uartlite.c: Serial driver for Xilinx uartlite serial controller
  4 *
  5 * Copyright (C) 2006 Peter Korsgaard <jacmet@sunsite.dk>
  6 * Copyright (C) 2007 Secret Lab Technologies Ltd.
 
 
 
 
  7 */
  8
  9#include <linux/platform_device.h>
 10#include <linux/module.h>
 11#include <linux/bitfield.h>
 12#include <linux/console.h>
 13#include <linux/serial.h>
 14#include <linux/serial_core.h>
 15#include <linux/tty.h>
 16#include <linux/tty_flip.h>
 17#include <linux/delay.h>
 18#include <linux/interrupt.h>
 19#include <linux/init.h>
 20#include <linux/io.h>
 21#include <linux/iopoll.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#include <linux/clk.h>
 27#include <linux/pm_runtime.h>
 28
 29#define ULITE_NAME		"ttyUL"
 30#define ULITE_MAJOR		204
 31#define ULITE_MINOR		187
 32#define ULITE_NR_UARTS		CONFIG_SERIAL_UARTLITE_NR_UARTS
 33
 34/* ---------------------------------------------------------------------
 35 * Register definitions
 36 *
 37 * For register details see datasheet:
 38 * https://www.xilinx.com/support/documentation/ip_documentation/opb_uartlite.pdf
 39 */
 40
 41#define ULITE_RX		0x00
 42#define ULITE_TX		0x04
 43#define ULITE_STATUS		0x08
 44#define ULITE_CONTROL		0x0c
 45
 46#define ULITE_REGION		16
 47
 48#define ULITE_STATUS_RXVALID	0x01
 49#define ULITE_STATUS_RXFULL	0x02
 50#define ULITE_STATUS_TXEMPTY	0x04
 51#define ULITE_STATUS_TXFULL	0x08
 52#define ULITE_STATUS_IE		0x10
 53#define ULITE_STATUS_OVERRUN	0x20
 54#define ULITE_STATUS_FRAME	0x40
 55#define ULITE_STATUS_PARITY	0x80
 56
 57#define ULITE_CONTROL_RST_TX	0x01
 58#define ULITE_CONTROL_RST_RX	0x02
 59#define ULITE_CONTROL_IE	0x10
 60#define UART_AUTOSUSPEND_TIMEOUT	3000	/* ms */
 61
 62/* Static pointer to console port */
 63#ifdef CONFIG_SERIAL_UARTLITE_CONSOLE
 64static struct uart_port *console_port;
 65#endif
 66
 67/**
 68 * struct uartlite_data: Driver private data
 69 * reg_ops: Functions to read/write registers
 70 * clk: Our parent clock, if present
 71 * baud: The baud rate configured when this device was synthesized
 72 * cflags: The cflags for parity and data bits
 73 */
 74struct uartlite_data {
 75	const struct uartlite_reg_ops *reg_ops;
 76	struct clk *clk;
 77	unsigned int baud;
 78	tcflag_t cflags;
 79};
 80
 81struct uartlite_reg_ops {
 82	u32 (*in)(void __iomem *addr);
 83	void (*out)(u32 val, void __iomem *addr);
 84};
 85
 86static u32 uartlite_inbe32(void __iomem *addr)
 87{
 88	return ioread32be(addr);
 89}
 90
 91static void uartlite_outbe32(u32 val, void __iomem *addr)
 92{
 93	iowrite32be(val, addr);
 94}
 95
 96static const struct uartlite_reg_ops uartlite_be = {
 97	.in = uartlite_inbe32,
 98	.out = uartlite_outbe32,
 99};
100
101static u32 uartlite_inle32(void __iomem *addr)
102{
103	return ioread32(addr);
104}
105
106static void uartlite_outle32(u32 val, void __iomem *addr)
107{
108	iowrite32(val, addr);
109}
110
111static const struct uartlite_reg_ops uartlite_le = {
112	.in = uartlite_inle32,
113	.out = uartlite_outle32,
114};
115
116static inline u32 uart_in32(u32 offset, struct uart_port *port)
117{
118	struct uartlite_data *pdata = port->private_data;
119
120	return pdata->reg_ops->in(port->membase + offset);
121}
122
123static inline void uart_out32(u32 val, u32 offset, struct uart_port *port)
124{
125	struct uartlite_data *pdata = port->private_data;
126
127	pdata->reg_ops->out(val, port->membase + offset);
128}
129
130static struct uart_port ulite_ports[ULITE_NR_UARTS];
131
132static struct uart_driver ulite_uart_driver;
133
134/* ---------------------------------------------------------------------
135 * Core UART driver operations
136 */
137
138static int ulite_receive(struct uart_port *port, int stat)
139{
140	struct tty_port *tport = &port->state->port;
141	unsigned char ch = 0;
142	char flag = TTY_NORMAL;
143
144	if ((stat & (ULITE_STATUS_RXVALID | ULITE_STATUS_OVERRUN
145		     | ULITE_STATUS_FRAME)) == 0)
146		return 0;
147
148	/* stats */
149	if (stat & ULITE_STATUS_RXVALID) {
150		port->icount.rx++;
151		ch = uart_in32(ULITE_RX, port);
152
153		if (stat & ULITE_STATUS_PARITY)
154			port->icount.parity++;
155	}
156
157	if (stat & ULITE_STATUS_OVERRUN)
158		port->icount.overrun++;
159
160	if (stat & ULITE_STATUS_FRAME)
161		port->icount.frame++;
162
163
164	/* drop byte with parity error if IGNPAR specificed */
165	if (stat & port->ignore_status_mask & ULITE_STATUS_PARITY)
166		stat &= ~ULITE_STATUS_RXVALID;
167
168	stat &= port->read_status_mask;
169
170	if (stat & ULITE_STATUS_PARITY)
171		flag = TTY_PARITY;
172
173
174	stat &= ~port->ignore_status_mask;
175
176	if (stat & ULITE_STATUS_RXVALID)
177		tty_insert_flip_char(tport, ch, flag);
178
179	if (stat & ULITE_STATUS_FRAME)
180		tty_insert_flip_char(tport, 0, TTY_FRAME);
181
182	if (stat & ULITE_STATUS_OVERRUN)
183		tty_insert_flip_char(tport, 0, TTY_OVERRUN);
184
185	return 1;
186}
187
188static int ulite_transmit(struct uart_port *port, int stat)
189{
190	struct circ_buf *xmit  = &port->state->xmit;
191
192	if (stat & ULITE_STATUS_TXFULL)
193		return 0;
194
195	if (port->x_char) {
196		uart_out32(port->x_char, ULITE_TX, port);
197		port->x_char = 0;
198		port->icount.tx++;
199		return 1;
200	}
201
202	if (uart_circ_empty(xmit) || uart_tx_stopped(port))
203		return 0;
204
205	uart_out32(xmit->buf[xmit->tail], ULITE_TX, port);
206	uart_xmit_advance(port, 1);
 
207
208	/* wake up */
209	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
210		uart_write_wakeup(port);
211
212	return 1;
213}
214
215static irqreturn_t ulite_isr(int irq, void *dev_id)
216{
217	struct uart_port *port = dev_id;
218	int stat, busy, n = 0;
219	unsigned long flags;
220
221	do {
222		spin_lock_irqsave(&port->lock, flags);
223		stat = uart_in32(ULITE_STATUS, port);
224		busy  = ulite_receive(port, stat);
225		busy |= ulite_transmit(port, stat);
226		spin_unlock_irqrestore(&port->lock, flags);
227		n++;
228	} while (busy);
229
230	/* work done? */
231	if (n > 1) {
232		tty_flip_buffer_push(&port->state->port);
233		return IRQ_HANDLED;
234	} else {
235		return IRQ_NONE;
236	}
237}
238
239static unsigned int ulite_tx_empty(struct uart_port *port)
240{
241	unsigned long flags;
242	unsigned int ret;
243
244	spin_lock_irqsave(&port->lock, flags);
245	ret = uart_in32(ULITE_STATUS, port);
246	spin_unlock_irqrestore(&port->lock, flags);
247
248	return ret & ULITE_STATUS_TXEMPTY ? TIOCSER_TEMT : 0;
249}
250
251static unsigned int ulite_get_mctrl(struct uart_port *port)
252{
253	return TIOCM_CTS | TIOCM_DSR | TIOCM_CAR;
254}
255
256static void ulite_set_mctrl(struct uart_port *port, unsigned int mctrl)
257{
258	/* N/A */
259}
260
261static void ulite_stop_tx(struct uart_port *port)
262{
263	/* N/A */
264}
265
266static void ulite_start_tx(struct uart_port *port)
267{
268	ulite_transmit(port, uart_in32(ULITE_STATUS, port));
269}
270
271static void ulite_stop_rx(struct uart_port *port)
272{
273	/* don't forward any more data (like !CREAD) */
274	port->ignore_status_mask = ULITE_STATUS_RXVALID | ULITE_STATUS_PARITY
275		| ULITE_STATUS_FRAME | ULITE_STATUS_OVERRUN;
276}
277
 
 
 
 
 
278static void ulite_break_ctl(struct uart_port *port, int ctl)
279{
280	/* N/A */
281}
282
283static int ulite_startup(struct uart_port *port)
284{
285	struct uartlite_data *pdata = port->private_data;
286	int ret;
287
288	ret = clk_enable(pdata->clk);
289	if (ret) {
290		dev_err(port->dev, "Failed to enable clock\n");
291		return ret;
292	}
293
294	ret = request_irq(port->irq, ulite_isr, IRQF_SHARED | IRQF_TRIGGER_RISING,
295			  "uartlite", port);
296	if (ret)
297		return ret;
298
299	uart_out32(ULITE_CONTROL_RST_RX | ULITE_CONTROL_RST_TX,
300		ULITE_CONTROL, port);
301	uart_out32(ULITE_CONTROL_IE, ULITE_CONTROL, port);
302
303	return 0;
304}
305
306static void ulite_shutdown(struct uart_port *port)
307{
308	struct uartlite_data *pdata = port->private_data;
309
310	uart_out32(0, ULITE_CONTROL, port);
311	uart_in32(ULITE_CONTROL, port); /* dummy */
312	free_irq(port->irq, port);
313	clk_disable(pdata->clk);
314}
315
316static void ulite_set_termios(struct uart_port *port,
317			      struct ktermios *termios,
318			      const struct ktermios *old)
319{
320	unsigned long flags;
321	struct uartlite_data *pdata = port->private_data;
322
323	/* Set termios to what the hardware supports */
324	termios->c_iflag &= ~BRKINT;
325	termios->c_cflag &= ~(CSTOPB | PARENB | PARODD | CSIZE);
326	termios->c_cflag |= pdata->cflags & (PARENB | PARODD | CSIZE);
327	tty_termios_encode_baud_rate(termios, pdata->baud, pdata->baud);
328
329	spin_lock_irqsave(&port->lock, flags);
330
331	port->read_status_mask = ULITE_STATUS_RXVALID | ULITE_STATUS_OVERRUN
332		| ULITE_STATUS_TXFULL;
333
334	if (termios->c_iflag & INPCK)
335		port->read_status_mask |=
336			ULITE_STATUS_PARITY | ULITE_STATUS_FRAME;
337
338	port->ignore_status_mask = 0;
339	if (termios->c_iflag & IGNPAR)
340		port->ignore_status_mask |= ULITE_STATUS_PARITY
341			| ULITE_STATUS_FRAME | ULITE_STATUS_OVERRUN;
342
343	/* ignore all characters if CREAD is not set */
344	if ((termios->c_cflag & CREAD) == 0)
345		port->ignore_status_mask |=
346			ULITE_STATUS_RXVALID | ULITE_STATUS_PARITY
347			| ULITE_STATUS_FRAME | ULITE_STATUS_OVERRUN;
348
349	/* update timeout */
350	uart_update_timeout(port, termios->c_cflag, pdata->baud);
 
351
352	spin_unlock_irqrestore(&port->lock, flags);
353}
354
355static const char *ulite_type(struct uart_port *port)
356{
357	return port->type == PORT_UARTLITE ? "uartlite" : NULL;
358}
359
360static void ulite_release_port(struct uart_port *port)
361{
362	release_mem_region(port->mapbase, ULITE_REGION);
363	iounmap(port->membase);
364	port->membase = NULL;
365}
366
367static int ulite_request_port(struct uart_port *port)
368{
369	struct uartlite_data *pdata = port->private_data;
370	int ret;
371
372	pr_debug("ulite console: port=%p; port->mapbase=%llx\n",
373		 port, (unsigned long long) port->mapbase);
374
375	if (!request_mem_region(port->mapbase, ULITE_REGION, "uartlite")) {
376		dev_err(port->dev, "Memory region busy\n");
377		return -EBUSY;
378	}
379
380	port->membase = ioremap(port->mapbase, ULITE_REGION);
381	if (!port->membase) {
382		dev_err(port->dev, "Unable to map registers\n");
383		release_mem_region(port->mapbase, ULITE_REGION);
384		return -EBUSY;
385	}
386
387	pdata->reg_ops = &uartlite_be;
388	ret = uart_in32(ULITE_CONTROL, port);
389	uart_out32(ULITE_CONTROL_RST_TX, ULITE_CONTROL, port);
390	ret = uart_in32(ULITE_STATUS, port);
391	/* Endianess detection */
392	if ((ret & ULITE_STATUS_TXEMPTY) != ULITE_STATUS_TXEMPTY)
393		pdata->reg_ops = &uartlite_le;
394
395	return 0;
396}
397
398static void ulite_config_port(struct uart_port *port, int flags)
399{
400	if (!ulite_request_port(port))
401		port->type = PORT_UARTLITE;
402}
403
404static int ulite_verify_port(struct uart_port *port, struct serial_struct *ser)
405{
406	/* we don't want the core code to modify any port params */
407	return -EINVAL;
408}
409
410static void ulite_pm(struct uart_port *port, unsigned int state,
411		     unsigned int oldstate)
412{
413	int ret;
414
415	if (!state) {
416		ret = pm_runtime_get_sync(port->dev);
417		if (ret < 0)
418			dev_err(port->dev, "Failed to enable clocks\n");
419	} else {
420		pm_runtime_mark_last_busy(port->dev);
421		pm_runtime_put_autosuspend(port->dev);
422	}
423}
424
425#ifdef CONFIG_CONSOLE_POLL
426static int ulite_get_poll_char(struct uart_port *port)
427{
428	if (!(uart_in32(ULITE_STATUS, port) & ULITE_STATUS_RXVALID))
 
429		return NO_POLL_CHAR;
430
431	return uart_in32(ULITE_RX, port);
432}
433
434static void ulite_put_poll_char(struct uart_port *port, unsigned char ch)
435{
436	while (uart_in32(ULITE_STATUS, port) & ULITE_STATUS_TXFULL)
437		cpu_relax();
438
439	/* write char to device */
440	uart_out32(ch, ULITE_TX, port);
441}
442#endif
443
444static const struct uart_ops ulite_ops = {
445	.tx_empty	= ulite_tx_empty,
446	.set_mctrl	= ulite_set_mctrl,
447	.get_mctrl	= ulite_get_mctrl,
448	.stop_tx	= ulite_stop_tx,
449	.start_tx	= ulite_start_tx,
450	.stop_rx	= ulite_stop_rx,
 
451	.break_ctl	= ulite_break_ctl,
452	.startup	= ulite_startup,
453	.shutdown	= ulite_shutdown,
454	.set_termios	= ulite_set_termios,
455	.type		= ulite_type,
456	.release_port	= ulite_release_port,
457	.request_port	= ulite_request_port,
458	.config_port	= ulite_config_port,
459	.verify_port	= ulite_verify_port,
460	.pm		= ulite_pm,
461#ifdef CONFIG_CONSOLE_POLL
462	.poll_get_char	= ulite_get_poll_char,
463	.poll_put_char	= ulite_put_poll_char,
464#endif
465};
466
467/* ---------------------------------------------------------------------
468 * Console driver operations
469 */
470
471#ifdef CONFIG_SERIAL_UARTLITE_CONSOLE
472static void ulite_console_wait_tx(struct uart_port *port)
473{
 
474	u8 val;
475
476	/*
477	 * Spin waiting for TX fifo to have space available.
478	 * When using the Microblaze Debug Module this can take up to 1s
479	 */
480	if (read_poll_timeout_atomic(uart_in32, val, !(val & ULITE_STATUS_TXFULL),
481				     0, 1000000, false, ULITE_STATUS, port))
482		dev_warn(port->dev,
483			 "timeout waiting for TX buffer empty\n");
484}
485
486static void ulite_console_putchar(struct uart_port *port, unsigned char ch)
487{
488	ulite_console_wait_tx(port);
489	uart_out32(ch, ULITE_TX, port);
490}
491
492static void ulite_console_write(struct console *co, const char *s,
493				unsigned int count)
494{
495	struct uart_port *port = console_port;
496	unsigned long flags;
497	unsigned int ier;
498	int locked = 1;
499
500	if (oops_in_progress) {
501		locked = spin_trylock_irqsave(&port->lock, flags);
502	} else
503		spin_lock_irqsave(&port->lock, flags);
504
505	/* save and disable interrupt */
506	ier = uart_in32(ULITE_STATUS, port) & ULITE_STATUS_IE;
507	uart_out32(0, ULITE_CONTROL, port);
508
509	uart_console_write(port, s, count, ulite_console_putchar);
510
511	ulite_console_wait_tx(port);
512
513	/* restore interrupt state */
514	if (ier)
515		uart_out32(ULITE_CONTROL_IE, ULITE_CONTROL, port);
516
517	if (locked)
518		spin_unlock_irqrestore(&port->lock, flags);
519}
520
521static int ulite_console_setup(struct console *co, char *options)
522{
523	struct uart_port *port = NULL;
524	int baud = 9600;
525	int bits = 8;
526	int parity = 'n';
527	int flow = 'n';
528
529	if (co->index >= 0 && co->index < ULITE_NR_UARTS)
530		port = ulite_ports + co->index;
 
 
531
532	/* Has the device been initialized yet? */
533	if (!port || !port->mapbase) {
534		pr_debug("console on ttyUL%i not present\n", co->index);
535		return -ENODEV;
536	}
537
538	console_port = port;
539
540	/* not initialized yet? */
541	if (!port->membase) {
542		if (ulite_request_port(port))
543			return -ENODEV;
544	}
545
546	if (options)
547		uart_parse_options(options, &baud, &parity, &bits, &flow);
548
549	return uart_set_options(port, co, baud, parity, bits, flow);
550}
551
 
 
552static struct console ulite_console = {
553	.name	= ULITE_NAME,
554	.write	= ulite_console_write,
555	.device	= uart_console_device,
556	.setup	= ulite_console_setup,
557	.flags	= CON_PRINTBUFFER,
558	.index	= -1, /* Specified on the cmdline (e.g. console=ttyUL0 ) */
559	.data	= &ulite_uart_driver,
560};
561
562static void early_uartlite_putc(struct uart_port *port, unsigned char c)
563{
564	/*
565	 * Limit how many times we'll spin waiting for TX FIFO status.
566	 * This will prevent lockups if the base address is incorrectly
567	 * set, or any other issue on the UARTLITE.
568	 * This limit is pretty arbitrary, unless we are at about 10 baud
569	 * we'll never timeout on a working UART.
570	 */
571	unsigned retries = 1000000;
572
573	while (--retries &&
574	       (readl(port->membase + ULITE_STATUS) & ULITE_STATUS_TXFULL))
575		;
576
577	/* Only attempt the iowrite if we didn't timeout */
578	if (retries)
579		writel(c & 0xff, port->membase + ULITE_TX);
580}
581
582static void early_uartlite_write(struct console *console,
583				 const char *s, unsigned n)
584{
585	struct earlycon_device *device = console->data;
586	uart_console_write(&device->port, s, n, early_uartlite_putc);
587}
588
589static int __init early_uartlite_setup(struct earlycon_device *device,
590				       const char *options)
591{
592	if (!device->port.membase)
593		return -ENODEV;
594
595	device->con->write = early_uartlite_write;
596	return 0;
597}
598EARLYCON_DECLARE(uartlite, early_uartlite_setup);
599OF_EARLYCON_DECLARE(uartlite_b, "xlnx,opb-uartlite-1.00.b", early_uartlite_setup);
600OF_EARLYCON_DECLARE(uartlite_a, "xlnx,xps-uartlite-1.00.a", early_uartlite_setup);
601
602#endif /* CONFIG_SERIAL_UARTLITE_CONSOLE */
603
604static struct uart_driver ulite_uart_driver = {
605	.owner		= THIS_MODULE,
606	.driver_name	= "uartlite",
607	.dev_name	= ULITE_NAME,
608	.major		= ULITE_MAJOR,
609	.minor		= ULITE_MINOR,
610	.nr		= ULITE_NR_UARTS,
611#ifdef CONFIG_SERIAL_UARTLITE_CONSOLE
612	.cons		= &ulite_console,
613#endif
614};
615
616/* ---------------------------------------------------------------------
617 * Port assignment functions (mapping devices to uart_port structures)
618 */
619
620/** ulite_assign: register a uartlite device with the driver
621 *
622 * @dev: pointer to device structure
623 * @id: requested id number.  Pass -1 for automatic port assignment
624 * @base: base address of uartlite registers
625 * @irq: irq number for uartlite
626 * @pdata: private data for uartlite
627 *
628 * Returns: 0 on success, <0 otherwise
629 */
630static int ulite_assign(struct device *dev, int id, phys_addr_t base, int irq,
631			struct uartlite_data *pdata)
632{
633	struct uart_port *port;
634	int rc;
635
636	/* if id = -1; then scan for a free id and use that */
637	if (id < 0) {
638		for (id = 0; id < ULITE_NR_UARTS; id++)
639			if (ulite_ports[id].mapbase == 0)
640				break;
641	}
642	if (id < 0 || id >= ULITE_NR_UARTS) {
643		dev_err(dev, "%s%i too large\n", ULITE_NAME, id);
644		return -EINVAL;
645	}
646
647	if ((ulite_ports[id].mapbase) && (ulite_ports[id].mapbase != base)) {
648		dev_err(dev, "cannot assign to %s%i; it is already in use\n",
649			ULITE_NAME, id);
650		return -EBUSY;
651	}
652
653	port = &ulite_ports[id];
654
655	spin_lock_init(&port->lock);
656	port->fifosize = 16;
657	port->regshift = 2;
658	port->iotype = UPIO_MEM;
659	port->iobase = 1; /* mark port in use */
660	port->mapbase = base;
661	port->membase = NULL;
662	port->ops = &ulite_ops;
663	port->irq = irq;
664	port->flags = UPF_BOOT_AUTOCONF;
665	port->dev = dev;
666	port->type = PORT_UNKNOWN;
667	port->line = id;
668	port->private_data = pdata;
669
670	dev_set_drvdata(dev, port);
671
672	/* Register the port */
673	rc = uart_add_one_port(&ulite_uart_driver, port);
674	if (rc) {
675		dev_err(dev, "uart_add_one_port() failed; err=%i\n", rc);
676		port->mapbase = 0;
677		dev_set_drvdata(dev, NULL);
678		return rc;
679	}
680
681	return 0;
682}
683
684/** ulite_release: register a uartlite device with the driver
685 *
686 * @dev: pointer to device structure
687 */
688static int ulite_release(struct device *dev)
689{
690	struct uart_port *port = dev_get_drvdata(dev);
691	int rc = 0;
692
693	if (port) {
694		rc = uart_remove_one_port(&ulite_uart_driver, port);
695		dev_set_drvdata(dev, NULL);
696		port->mapbase = 0;
697	}
698
699	return rc;
700}
701
702/**
703 * ulite_suspend - Stop the device.
704 *
705 * @dev: handle to the device structure.
706 * Return: 0 always.
707 */
708static int __maybe_unused ulite_suspend(struct device *dev)
709{
710	struct uart_port *port = dev_get_drvdata(dev);
711
712	if (port)
713		uart_suspend_port(&ulite_uart_driver, port);
714
715	return 0;
716}
717
718/**
719 * ulite_resume - Resume the device.
720 *
721 * @dev: handle to the device structure.
722 * Return: 0 on success, errno otherwise.
723 */
724static int __maybe_unused ulite_resume(struct device *dev)
725{
726	struct uart_port *port = dev_get_drvdata(dev);
727
728	if (port)
729		uart_resume_port(&ulite_uart_driver, port);
730
731	return 0;
732}
733
734static int __maybe_unused ulite_runtime_suspend(struct device *dev)
735{
736	struct uart_port *port = dev_get_drvdata(dev);
737	struct uartlite_data *pdata = port->private_data;
738
739	clk_disable(pdata->clk);
740	return 0;
741};
742
743static int __maybe_unused ulite_runtime_resume(struct device *dev)
744{
745	struct uart_port *port = dev_get_drvdata(dev);
746	struct uartlite_data *pdata = port->private_data;
747	int ret;
748
749	ret = clk_enable(pdata->clk);
750	if (ret) {
751		dev_err(dev, "Cannot enable clock.\n");
752		return ret;
753	}
754	return 0;
755}
756
757/* ---------------------------------------------------------------------
758 * Platform bus binding
759 */
760
761static const struct dev_pm_ops ulite_pm_ops = {
762	SET_SYSTEM_SLEEP_PM_OPS(ulite_suspend, ulite_resume)
763	SET_RUNTIME_PM_OPS(ulite_runtime_suspend,
764			   ulite_runtime_resume, NULL)
765};
766
767#if defined(CONFIG_OF)
768/* Match table for of_platform binding */
769static const struct of_device_id ulite_of_match[] = {
770	{ .compatible = "xlnx,opb-uartlite-1.00.b", },
771	{ .compatible = "xlnx,xps-uartlite-1.00.a", },
772	{}
773};
774MODULE_DEVICE_TABLE(of, ulite_of_match);
 
 
775#endif /* CONFIG_OF */
776
777static int ulite_probe(struct platform_device *pdev)
778{
779	struct resource *res;
780	struct uartlite_data *pdata;
781	int irq, ret;
782	int id = pdev->id;
 
 
783
784	pdata = devm_kzalloc(&pdev->dev, sizeof(struct uartlite_data),
785			     GFP_KERNEL);
786	if (!pdata)
787		return -ENOMEM;
788
789	if (IS_ENABLED(CONFIG_OF)) {
790		const char *prop;
791		struct device_node *np = pdev->dev.of_node;
792		u32 val = 0;
793
794		prop = "port-number";
795		ret = of_property_read_u32(np, prop, &id);
796		if (ret && ret != -EINVAL)
797of_err:
798			return dev_err_probe(&pdev->dev, ret,
799					     "could not read %s\n", prop);
800
801		prop = "current-speed";
802		ret = of_property_read_u32(np, prop, &pdata->baud);
803		if (ret)
804			goto of_err;
805
806		prop = "xlnx,use-parity";
807		ret = of_property_read_u32(np, prop, &val);
808		if (ret && ret != -EINVAL)
809			goto of_err;
810
811		if (val) {
812			prop = "xlnx,odd-parity";
813			ret = of_property_read_u32(np, prop, &val);
814			if (ret)
815				goto of_err;
816
817			if (val)
818				pdata->cflags |= PARODD;
819			pdata->cflags |= PARENB;
820		}
821
822		val = 8;
823		prop = "xlnx,data-bits";
824		ret = of_property_read_u32(np, prop, &val);
825		if (ret && ret != -EINVAL)
826			goto of_err;
827
828		switch (val) {
829		case 5:
830			pdata->cflags |= CS5;
831			break;
832		case 6:
833			pdata->cflags |= CS6;
834			break;
835		case 7:
836			pdata->cflags |= CS7;
837			break;
838		case 8:
839			pdata->cflags |= CS8;
840			break;
841		default:
842			return dev_err_probe(&pdev->dev, -EINVAL,
843					     "bad data bits %d\n", val);
844		}
845	} else {
846		pdata->baud = 9600;
847		pdata->cflags = CS8;
848	}
849
850	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
851	if (!res)
852		return -ENODEV;
853
854	irq = platform_get_irq(pdev, 0);
855	if (irq < 0)
856		return irq;
857
858	pdata->clk = devm_clk_get(&pdev->dev, "s_axi_aclk");
859	if (IS_ERR(pdata->clk)) {
860		if (PTR_ERR(pdata->clk) != -ENOENT)
861			return PTR_ERR(pdata->clk);
862
863		/*
864		 * Clock framework support is optional, continue on
865		 * anyways if we don't find a matching clock.
866		 */
867		pdata->clk = NULL;
868	}
869
870	ret = clk_prepare_enable(pdata->clk);
871	if (ret) {
872		dev_err(&pdev->dev, "Failed to prepare clock\n");
873		return ret;
874	}
875
876	pm_runtime_use_autosuspend(&pdev->dev);
877	pm_runtime_set_autosuspend_delay(&pdev->dev, UART_AUTOSUSPEND_TIMEOUT);
878	pm_runtime_set_active(&pdev->dev);
879	pm_runtime_enable(&pdev->dev);
880
881	if (!ulite_uart_driver.state) {
882		dev_dbg(&pdev->dev, "uartlite: calling uart_register_driver()\n");
883		ret = uart_register_driver(&ulite_uart_driver);
884		if (ret < 0) {
885			dev_err(&pdev->dev, "Failed to register driver\n");
886			clk_disable_unprepare(pdata->clk);
887			return ret;
888		}
889	}
890
891	ret = ulite_assign(&pdev->dev, id, res->start, irq, pdata);
892
893	pm_runtime_mark_last_busy(&pdev->dev);
894	pm_runtime_put_autosuspend(&pdev->dev);
895
896	return ret;
897}
898
899static int ulite_remove(struct platform_device *pdev)
900{
901	struct uart_port *port = dev_get_drvdata(&pdev->dev);
902	struct uartlite_data *pdata = port->private_data;
903	int rc;
904
905	clk_disable_unprepare(pdata->clk);
906	rc = ulite_release(&pdev->dev);
907	pm_runtime_disable(&pdev->dev);
908	pm_runtime_set_suspended(&pdev->dev);
909	pm_runtime_dont_use_autosuspend(&pdev->dev);
910	return rc;
911}
912
913/* work with hotplug and coldplug */
914MODULE_ALIAS("platform:uartlite");
915
916static struct platform_driver ulite_platform_driver = {
917	.probe = ulite_probe,
918	.remove = ulite_remove,
919	.driver = {
 
920		.name  = "uartlite",
921		.of_match_table = of_match_ptr(ulite_of_match),
922		.pm = &ulite_pm_ops,
923	},
924};
925
926/* ---------------------------------------------------------------------
927 * Module setup/teardown
928 */
929
930static int __init ulite_init(void)
931{
 
 
 
 
 
 
932
933	pr_debug("uartlite: calling platform_driver_register()\n");
934	return platform_driver_register(&ulite_platform_driver);
 
 
 
 
 
 
 
 
 
 
935}
936
937static void __exit ulite_exit(void)
938{
939	platform_driver_unregister(&ulite_platform_driver);
940	if (ulite_uart_driver.state)
941		uart_unregister_driver(&ulite_uart_driver);
942}
943
944module_init(ulite_init);
945module_exit(ulite_exit);
946
947MODULE_AUTHOR("Peter Korsgaard <jacmet@sunsite.dk>");
948MODULE_DESCRIPTION("Xilinx uartlite serial driver");
949MODULE_LICENSE("GPL");