Linux Audio

Check our new training course

Loading...
v5.4
  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/console.h>
 12#include <linux/serial.h>
 13#include <linux/serial_core.h>
 14#include <linux/tty.h>
 15#include <linux/tty_flip.h>
 16#include <linux/delay.h>
 17#include <linux/interrupt.h>
 18#include <linux/init.h>
 19#include <linux/io.h>
 20#include <linux/of.h>
 21#include <linux/of_address.h>
 22#include <linux/of_device.h>
 23#include <linux/of_platform.h>
 24#include <linux/clk.h>
 25#include <linux/pm_runtime.h>
 26
 27#define ULITE_NAME		"ttyUL"
 28#define ULITE_MAJOR		204
 29#define ULITE_MINOR		187
 30#define ULITE_NR_UARTS		CONFIG_SERIAL_UARTLITE_NR_UARTS
 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#define UART_AUTOSUSPEND_TIMEOUT	3000
 59
 60/* Static pointer to console port */
 61#ifdef CONFIG_SERIAL_UARTLITE_CONSOLE
 62static struct uart_port *console_port;
 63#endif
 64
 65struct uartlite_data {
 66	const struct uartlite_reg_ops *reg_ops;
 67	struct clk *clk;
 68	struct uart_driver *ulite_uart_driver;
 69};
 70
 71struct uartlite_reg_ops {
 72	u32 (*in)(void __iomem *addr);
 73	void (*out)(u32 val, void __iomem *addr);
 74};
 75
 76static u32 uartlite_inbe32(void __iomem *addr)
 77{
 78	return ioread32be(addr);
 79}
 80
 81static void uartlite_outbe32(u32 val, void __iomem *addr)
 82{
 83	iowrite32be(val, addr);
 84}
 85
 86static const struct uartlite_reg_ops uartlite_be = {
 87	.in = uartlite_inbe32,
 88	.out = uartlite_outbe32,
 89};
 90
 91static u32 uartlite_inle32(void __iomem *addr)
 92{
 93	return ioread32(addr);
 94}
 95
 96static void uartlite_outle32(u32 val, void __iomem *addr)
 97{
 98	iowrite32(val, addr);
 99}
100
101static const struct uartlite_reg_ops uartlite_le = {
102	.in = uartlite_inle32,
103	.out = uartlite_outle32,
104};
105
106static inline u32 uart_in32(u32 offset, struct uart_port *port)
107{
108	struct uartlite_data *pdata = port->private_data;
109
110	return pdata->reg_ops->in(port->membase + offset);
111}
112
113static inline void uart_out32(u32 val, u32 offset, struct uart_port *port)
114{
115	struct uartlite_data *pdata = port->private_data;
116
117	pdata->reg_ops->out(val, port->membase + offset);
118}
119
120static struct uart_port ulite_ports[ULITE_NR_UARTS];
121
122/* ---------------------------------------------------------------------
123 * Core UART driver operations
124 */
125
126static int ulite_receive(struct uart_port *port, int stat)
127{
128	struct tty_port *tport = &port->state->port;
129	unsigned char ch = 0;
130	char flag = TTY_NORMAL;
131
132	if ((stat & (ULITE_STATUS_RXVALID | ULITE_STATUS_OVERRUN
133		     | ULITE_STATUS_FRAME)) == 0)
134		return 0;
135
136	/* stats */
137	if (stat & ULITE_STATUS_RXVALID) {
138		port->icount.rx++;
139		ch = uart_in32(ULITE_RX, port);
140
141		if (stat & ULITE_STATUS_PARITY)
142			port->icount.parity++;
143	}
144
145	if (stat & ULITE_STATUS_OVERRUN)
146		port->icount.overrun++;
147
148	if (stat & ULITE_STATUS_FRAME)
149		port->icount.frame++;
150
151
152	/* drop byte with parity error if IGNPAR specificed */
153	if (stat & port->ignore_status_mask & ULITE_STATUS_PARITY)
154		stat &= ~ULITE_STATUS_RXVALID;
155
156	stat &= port->read_status_mask;
157
158	if (stat & ULITE_STATUS_PARITY)
159		flag = TTY_PARITY;
160
161
162	stat &= ~port->ignore_status_mask;
163
164	if (stat & ULITE_STATUS_RXVALID)
165		tty_insert_flip_char(tport, ch, flag);
166
167	if (stat & ULITE_STATUS_FRAME)
168		tty_insert_flip_char(tport, 0, TTY_FRAME);
169
170	if (stat & ULITE_STATUS_OVERRUN)
171		tty_insert_flip_char(tport, 0, TTY_OVERRUN);
172
173	return 1;
174}
175
176static int ulite_transmit(struct uart_port *port, int stat)
177{
178	struct circ_buf *xmit  = &port->state->xmit;
179
180	if (stat & ULITE_STATUS_TXFULL)
181		return 0;
182
183	if (port->x_char) {
184		uart_out32(port->x_char, ULITE_TX, port);
185		port->x_char = 0;
186		port->icount.tx++;
187		return 1;
188	}
189
190	if (uart_circ_empty(xmit) || uart_tx_stopped(port))
191		return 0;
192
193	uart_out32(xmit->buf[xmit->tail], ULITE_TX, port);
194	xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE-1);
195	port->icount.tx++;
196
197	/* wake up */
198	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
199		uart_write_wakeup(port);
200
201	return 1;
202}
203
204static irqreturn_t ulite_isr(int irq, void *dev_id)
205{
206	struct uart_port *port = dev_id;
207	int stat, busy, n = 0;
208	unsigned long flags;
209
210	do {
211		spin_lock_irqsave(&port->lock, flags);
212		stat = uart_in32(ULITE_STATUS, port);
213		busy  = ulite_receive(port, stat);
214		busy |= ulite_transmit(port, stat);
215		spin_unlock_irqrestore(&port->lock, flags);
216		n++;
217	} while (busy);
218
219	/* work done? */
220	if (n > 1) {
221		tty_flip_buffer_push(&port->state->port);
222		return IRQ_HANDLED;
223	} else {
224		return IRQ_NONE;
225	}
226}
227
228static unsigned int ulite_tx_empty(struct uart_port *port)
229{
230	unsigned long flags;
231	unsigned int ret;
232
233	spin_lock_irqsave(&port->lock, flags);
234	ret = uart_in32(ULITE_STATUS, port);
235	spin_unlock_irqrestore(&port->lock, flags);
236
237	return ret & ULITE_STATUS_TXEMPTY ? TIOCSER_TEMT : 0;
238}
239
240static unsigned int ulite_get_mctrl(struct uart_port *port)
241{
242	return TIOCM_CTS | TIOCM_DSR | TIOCM_CAR;
243}
244
245static void ulite_set_mctrl(struct uart_port *port, unsigned int mctrl)
246{
247	/* N/A */
248}
249
250static void ulite_stop_tx(struct uart_port *port)
251{
252	/* N/A */
253}
254
255static void ulite_start_tx(struct uart_port *port)
256{
257	ulite_transmit(port, uart_in32(ULITE_STATUS, port));
258}
259
260static void ulite_stop_rx(struct uart_port *port)
261{
262	/* don't forward any more data (like !CREAD) */
263	port->ignore_status_mask = ULITE_STATUS_RXVALID | ULITE_STATUS_PARITY
264		| ULITE_STATUS_FRAME | ULITE_STATUS_OVERRUN;
265}
266
 
 
 
 
 
267static void ulite_break_ctl(struct uart_port *port, int ctl)
268{
269	/* N/A */
270}
271
272static int ulite_startup(struct uart_port *port)
273{
274	struct uartlite_data *pdata = port->private_data;
275	int ret;
276
277	ret = clk_enable(pdata->clk);
278	if (ret) {
279		dev_err(port->dev, "Failed to enable clock\n");
280		return ret;
281	}
282
283	ret = request_irq(port->irq, ulite_isr, IRQF_SHARED | IRQF_TRIGGER_RISING,
284			  "uartlite", port);
285	if (ret)
286		return ret;
287
288	uart_out32(ULITE_CONTROL_RST_RX | ULITE_CONTROL_RST_TX,
289		ULITE_CONTROL, port);
290	uart_out32(ULITE_CONTROL_IE, ULITE_CONTROL, port);
291
292	return 0;
293}
294
295static void ulite_shutdown(struct uart_port *port)
296{
297	struct uartlite_data *pdata = port->private_data;
298
299	uart_out32(0, ULITE_CONTROL, port);
300	uart_in32(ULITE_CONTROL, port); /* dummy */
301	free_irq(port->irq, port);
302	clk_disable(pdata->clk);
303}
304
305static void ulite_set_termios(struct uart_port *port, struct ktermios *termios,
306			      struct ktermios *old)
307{
308	unsigned long flags;
309	unsigned int baud;
310
311	spin_lock_irqsave(&port->lock, flags);
312
313	port->read_status_mask = ULITE_STATUS_RXVALID | ULITE_STATUS_OVERRUN
314		| ULITE_STATUS_TXFULL;
315
316	if (termios->c_iflag & INPCK)
317		port->read_status_mask |=
318			ULITE_STATUS_PARITY | ULITE_STATUS_FRAME;
319
320	port->ignore_status_mask = 0;
321	if (termios->c_iflag & IGNPAR)
322		port->ignore_status_mask |= ULITE_STATUS_PARITY
323			| ULITE_STATUS_FRAME | ULITE_STATUS_OVERRUN;
324
325	/* ignore all characters if CREAD is not set */
326	if ((termios->c_cflag & CREAD) == 0)
327		port->ignore_status_mask |=
328			ULITE_STATUS_RXVALID | ULITE_STATUS_PARITY
329			| ULITE_STATUS_FRAME | ULITE_STATUS_OVERRUN;
330
331	/* update timeout */
332	baud = uart_get_baud_rate(port, termios, old, 0, 460800);
333	uart_update_timeout(port, termios->c_cflag, baud);
334
335	spin_unlock_irqrestore(&port->lock, flags);
336}
337
338static const char *ulite_type(struct uart_port *port)
339{
340	return port->type == PORT_UARTLITE ? "uartlite" : NULL;
341}
342
343static void ulite_release_port(struct uart_port *port)
344{
345	release_mem_region(port->mapbase, ULITE_REGION);
346	iounmap(port->membase);
347	port->membase = NULL;
348}
349
350static int ulite_request_port(struct uart_port *port)
351{
352	struct uartlite_data *pdata = port->private_data;
353	int ret;
354
355	pr_debug("ulite console: port=%p; port->mapbase=%llx\n",
356		 port, (unsigned long long) port->mapbase);
357
358	if (!request_mem_region(port->mapbase, ULITE_REGION, "uartlite")) {
359		dev_err(port->dev, "Memory region busy\n");
360		return -EBUSY;
361	}
362
363	port->membase = ioremap(port->mapbase, ULITE_REGION);
364	if (!port->membase) {
365		dev_err(port->dev, "Unable to map registers\n");
366		release_mem_region(port->mapbase, ULITE_REGION);
367		return -EBUSY;
368	}
369
370	pdata->reg_ops = &uartlite_be;
371	ret = uart_in32(ULITE_CONTROL, port);
372	uart_out32(ULITE_CONTROL_RST_TX, ULITE_CONTROL, port);
373	ret = uart_in32(ULITE_STATUS, port);
374	/* Endianess detection */
375	if ((ret & ULITE_STATUS_TXEMPTY) != ULITE_STATUS_TXEMPTY)
376		pdata->reg_ops = &uartlite_le;
377
378	return 0;
379}
380
381static void ulite_config_port(struct uart_port *port, int flags)
382{
383	if (!ulite_request_port(port))
384		port->type = PORT_UARTLITE;
385}
386
387static int ulite_verify_port(struct uart_port *port, struct serial_struct *ser)
388{
389	/* we don't want the core code to modify any port params */
390	return -EINVAL;
391}
392
393static void ulite_pm(struct uart_port *port, unsigned int state,
394		     unsigned int oldstate)
395{
396	if (!state) {
397		pm_runtime_get_sync(port->dev);
398	} else {
399		pm_runtime_mark_last_busy(port->dev);
400		pm_runtime_put_autosuspend(port->dev);
401	}
402}
403
404#ifdef CONFIG_CONSOLE_POLL
405static int ulite_get_poll_char(struct uart_port *port)
406{
407	if (!(uart_in32(ULITE_STATUS, port) & ULITE_STATUS_RXVALID))
 
408		return NO_POLL_CHAR;
409
410	return uart_in32(ULITE_RX, port);
411}
412
413static void ulite_put_poll_char(struct uart_port *port, unsigned char ch)
414{
415	while (uart_in32(ULITE_STATUS, port) & ULITE_STATUS_TXFULL)
416		cpu_relax();
417
418	/* write char to device */
419	uart_out32(ch, ULITE_TX, port);
420}
421#endif
422
423static const struct uart_ops ulite_ops = {
424	.tx_empty	= ulite_tx_empty,
425	.set_mctrl	= ulite_set_mctrl,
426	.get_mctrl	= ulite_get_mctrl,
427	.stop_tx	= ulite_stop_tx,
428	.start_tx	= ulite_start_tx,
429	.stop_rx	= ulite_stop_rx,
 
430	.break_ctl	= ulite_break_ctl,
431	.startup	= ulite_startup,
432	.shutdown	= ulite_shutdown,
433	.set_termios	= ulite_set_termios,
434	.type		= ulite_type,
435	.release_port	= ulite_release_port,
436	.request_port	= ulite_request_port,
437	.config_port	= ulite_config_port,
438	.verify_port	= ulite_verify_port,
439	.pm		= ulite_pm,
440#ifdef CONFIG_CONSOLE_POLL
441	.poll_get_char	= ulite_get_poll_char,
442	.poll_put_char	= ulite_put_poll_char,
443#endif
444};
445
446/* ---------------------------------------------------------------------
447 * Console driver operations
448 */
449
450#ifdef CONFIG_SERIAL_UARTLITE_CONSOLE
451static void ulite_console_wait_tx(struct uart_port *port)
452{
 
453	u8 val;
454	unsigned long timeout;
455
456	/*
457	 * Spin waiting for TX fifo to have space available.
458	 * When using the Microblaze Debug Module this can take up to 1s
459	 */
460	timeout = jiffies + msecs_to_jiffies(1000);
461	while (1) {
462		val = uart_in32(ULITE_STATUS, port);
463		if ((val & ULITE_STATUS_TXFULL) == 0)
464			break;
465		if (time_after(jiffies, timeout)) {
466			dev_warn(port->dev,
467				 "timeout waiting for TX buffer empty\n");
468			break;
469		}
470		cpu_relax();
471	}
472}
473
474static void ulite_console_putchar(struct uart_port *port, int ch)
475{
476	ulite_console_wait_tx(port);
477	uart_out32(ch, ULITE_TX, port);
478}
479
480static void ulite_console_write(struct console *co, const char *s,
481				unsigned int count)
482{
483	struct uart_port *port = console_port;
484	unsigned long flags;
485	unsigned int ier;
486	int locked = 1;
487
488	if (oops_in_progress) {
489		locked = spin_trylock_irqsave(&port->lock, flags);
490	} else
491		spin_lock_irqsave(&port->lock, flags);
492
493	/* save and disable interrupt */
494	ier = uart_in32(ULITE_STATUS, port) & ULITE_STATUS_IE;
495	uart_out32(0, ULITE_CONTROL, port);
496
497	uart_console_write(port, s, count, ulite_console_putchar);
498
499	ulite_console_wait_tx(port);
500
501	/* restore interrupt state */
502	if (ier)
503		uart_out32(ULITE_CONTROL_IE, ULITE_CONTROL, port);
504
505	if (locked)
506		spin_unlock_irqrestore(&port->lock, flags);
507}
508
509static int ulite_console_setup(struct console *co, char *options)
510{
511	struct uart_port *port;
512	int baud = 9600;
513	int bits = 8;
514	int parity = 'n';
515	int flow = 'n';
516
 
 
517
518	port = console_port;
519
520	/* Has the device been initialized yet? */
521	if (!port->mapbase) {
522		pr_debug("console on ttyUL%i not present\n", co->index);
523		return -ENODEV;
524	}
525
526	/* not initialized yet? */
527	if (!port->membase) {
528		if (ulite_request_port(port))
529			return -ENODEV;
530	}
531
532	if (options)
533		uart_parse_options(options, &baud, &parity, &bits, &flow);
534
535	return uart_set_options(port, co, baud, parity, bits, flow);
536}
537
538static struct uart_driver ulite_uart_driver;
539
540static struct console ulite_console = {
541	.name	= ULITE_NAME,
542	.write	= ulite_console_write,
543	.device	= uart_console_device,
544	.setup	= ulite_console_setup,
545	.flags	= CON_PRINTBUFFER,
546	.index	= -1, /* Specified on the cmdline (e.g. console=ttyUL0 ) */
547	.data	= &ulite_uart_driver,
548};
549
550static void early_uartlite_putc(struct uart_port *port, int c)
551{
552	/*
553	 * Limit how many times we'll spin waiting for TX FIFO status.
554	 * This will prevent lockups if the base address is incorrectly
555	 * set, or any other issue on the UARTLITE.
556	 * This limit is pretty arbitrary, unless we are at about 10 baud
557	 * we'll never timeout on a working UART.
558	 */
559
560	unsigned retries = 1000000;
561	/* read status bit - 0x8 offset */
562	while (--retries && (readl(port->membase + 8) & (1 << 3)))
563		;
564
565	/* Only attempt the iowrite if we didn't timeout */
566	/* write to TX_FIFO - 0x4 offset */
567	if (retries)
568		writel(c & 0xff, port->membase + 4);
569}
570
571static void early_uartlite_write(struct console *console,
572				 const char *s, unsigned n)
573{
574	struct earlycon_device *device = console->data;
575	uart_console_write(&device->port, s, n, early_uartlite_putc);
576}
577
578static int __init early_uartlite_setup(struct earlycon_device *device,
579				       const char *options)
580{
581	if (!device->port.membase)
582		return -ENODEV;
583
584	device->con->write = early_uartlite_write;
585	return 0;
586}
587EARLYCON_DECLARE(uartlite, early_uartlite_setup);
588OF_EARLYCON_DECLARE(uartlite_b, "xlnx,opb-uartlite-1.00.b", early_uartlite_setup);
589OF_EARLYCON_DECLARE(uartlite_a, "xlnx,xps-uartlite-1.00.a", early_uartlite_setup);
590
591#endif /* CONFIG_SERIAL_UARTLITE_CONSOLE */
592
593static struct uart_driver ulite_uart_driver = {
594	.owner		= THIS_MODULE,
595	.driver_name	= "uartlite",
596	.dev_name	= ULITE_NAME,
597	.major		= ULITE_MAJOR,
598	.minor		= ULITE_MINOR,
599	.nr		= ULITE_NR_UARTS,
600#ifdef CONFIG_SERIAL_UARTLITE_CONSOLE
601	.cons		= &ulite_console,
602#endif
603};
604
605/* ---------------------------------------------------------------------
606 * Port assignment functions (mapping devices to uart_port structures)
607 */
608
609/** ulite_assign: register a uartlite device with the driver
610 *
611 * @dev: pointer to device structure
612 * @id: requested id number.  Pass -1 for automatic port assignment
613 * @base: base address of uartlite registers
614 * @irq: irq number for uartlite
615 * @pdata: private data for uartlite
616 *
617 * Returns: 0 on success, <0 otherwise
618 */
619static int ulite_assign(struct device *dev, int id, u32 base, int irq,
620			struct uartlite_data *pdata)
621{
622	struct uart_port *port;
623	int rc;
624
625	/* if id = -1; then scan for a free id and use that */
626	if (id < 0) {
627		for (id = 0; id < ULITE_NR_UARTS; id++)
628			if (ulite_ports[id].mapbase == 0)
629				break;
630	}
631	if (id < 0 || id >= ULITE_NR_UARTS) {
632		dev_err(dev, "%s%i too large\n", ULITE_NAME, id);
633		return -EINVAL;
634	}
635
636	if ((ulite_ports[id].mapbase) && (ulite_ports[id].mapbase != base)) {
637		dev_err(dev, "cannot assign to %s%i; it is already in use\n",
638			ULITE_NAME, id);
639		return -EBUSY;
640	}
641
642	port = &ulite_ports[id];
643
644	spin_lock_init(&port->lock);
645	port->fifosize = 16;
646	port->regshift = 2;
647	port->iotype = UPIO_MEM;
648	port->iobase = 1; /* mark port in use */
649	port->mapbase = base;
650	port->membase = NULL;
651	port->ops = &ulite_ops;
652	port->irq = irq;
653	port->flags = UPF_BOOT_AUTOCONF;
654	port->dev = dev;
655	port->type = PORT_UNKNOWN;
656	port->line = id;
657	port->private_data = pdata;
658
659	dev_set_drvdata(dev, port);
660
661#ifdef CONFIG_SERIAL_UARTLITE_CONSOLE
662	/*
663	 * If console hasn't been found yet try to assign this port
664	 * because it is required to be assigned for console setup function.
665	 * If register_console() don't assign value, then console_port pointer
666	 * is cleanup.
667	 */
668	if (ulite_uart_driver.cons->index == -1)
669		console_port = port;
670#endif
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#ifdef CONFIG_SERIAL_UARTLITE_CONSOLE
682	/* This is not port which is used for console that's why clean it up */
683	if (ulite_uart_driver.cons->index == -1)
684		console_port = NULL;
685#endif
686
687	return 0;
688}
689
690/** ulite_release: register a uartlite device with the driver
691 *
692 * @dev: pointer to device structure
693 */
694static int ulite_release(struct device *dev)
695{
696	struct uart_port *port = dev_get_drvdata(dev);
697	int rc = 0;
698
699	if (port) {
700		struct uartlite_data *pdata = port->private_data;
701
702		rc = uart_remove_one_port(pdata->ulite_uart_driver, port);
703		dev_set_drvdata(dev, NULL);
704		port->mapbase = 0;
705	}
706
707	return rc;
708}
709
710/**
711 * ulite_suspend - Stop the device.
712 *
713 * @dev: handle to the device structure.
714 * Return: 0 always.
715 */
716static int __maybe_unused ulite_suspend(struct device *dev)
717{
718	struct uart_port *port = dev_get_drvdata(dev);
719
720	if (port) {
721		struct uartlite_data *pdata = port->private_data;
722
723		uart_suspend_port(pdata->ulite_uart_driver, port);
724	}
725
726	return 0;
727}
728
729/**
730 * ulite_resume - Resume the device.
731 *
732 * @dev: handle to the device structure.
733 * Return: 0 on success, errno otherwise.
734 */
735static int __maybe_unused ulite_resume(struct device *dev)
736{
737	struct uart_port *port = dev_get_drvdata(dev);
738
739	if (port) {
740		struct uartlite_data *pdata = port->private_data;
741
742		uart_resume_port(pdata->ulite_uart_driver, port);
743	}
744
745	return 0;
746}
747
748static int __maybe_unused ulite_runtime_suspend(struct device *dev)
749{
750	struct uart_port *port = dev_get_drvdata(dev);
751	struct uartlite_data *pdata = port->private_data;
752
753	clk_disable(pdata->clk);
754	return 0;
755};
756
757static int __maybe_unused ulite_runtime_resume(struct device *dev)
758{
759	struct uart_port *port = dev_get_drvdata(dev);
760	struct uartlite_data *pdata = port->private_data;
761
762	clk_enable(pdata->clk);
763	return 0;
764}
765/* ---------------------------------------------------------------------
766 * Platform bus binding
767 */
768
769static const struct dev_pm_ops ulite_pm_ops = {
770	SET_SYSTEM_SLEEP_PM_OPS(ulite_suspend, ulite_resume)
771	SET_RUNTIME_PM_OPS(ulite_runtime_suspend,
772			   ulite_runtime_resume, NULL)
773};
774
775#if defined(CONFIG_OF)
776/* Match table for of_platform binding */
777static const struct of_device_id ulite_of_match[] = {
778	{ .compatible = "xlnx,opb-uartlite-1.00.b", },
779	{ .compatible = "xlnx,xps-uartlite-1.00.a", },
780	{}
781};
782MODULE_DEVICE_TABLE(of, ulite_of_match);
 
 
783#endif /* CONFIG_OF */
784
785static int ulite_probe(struct platform_device *pdev)
786{
787	struct resource *res;
788	struct uartlite_data *pdata;
789	int irq, ret;
790	int id = pdev->id;
791#ifdef CONFIG_OF
792	const __be32 *prop;
793
794	prop = of_get_property(pdev->dev.of_node, "port-number", NULL);
795	if (prop)
796		id = be32_to_cpup(prop);
797#endif
798	if (id < 0) {
799		/* Look for a serialN alias */
800		id = of_alias_get_id(pdev->dev.of_node, "serial");
801		if (id < 0)
802			id = 0;
803	}
804
805	if (!ulite_uart_driver.state) {
806		dev_dbg(&pdev->dev, "uartlite: calling uart_register_driver()\n");
807		ret = uart_register_driver(&ulite_uart_driver);
808		if (ret < 0) {
809			dev_err(&pdev->dev, "Failed to register driver\n");
810			return ret;
811		}
812	}
813
814	pdata = devm_kzalloc(&pdev->dev, sizeof(struct uartlite_data),
815			     GFP_KERNEL);
816	if (!pdata)
817		return -ENOMEM;
818
819	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
820	if (!res)
821		return -ENODEV;
822
823	irq = platform_get_irq(pdev, 0);
824	if (irq <= 0)
825		return -ENXIO;
826
827	pdata->clk = devm_clk_get(&pdev->dev, "s_axi_aclk");
828	if (IS_ERR(pdata->clk)) {
829		if (PTR_ERR(pdata->clk) != -ENOENT)
830			return PTR_ERR(pdata->clk);
831
832		/*
833		 * Clock framework support is optional, continue on
834		 * anyways if we don't find a matching clock.
835		 */
836		pdata->clk = NULL;
837	}
838
839	pdata->ulite_uart_driver = &ulite_uart_driver;
840	ret = clk_prepare_enable(pdata->clk);
841	if (ret) {
842		dev_err(&pdev->dev, "Failed to prepare clock\n");
843		return ret;
844	}
845
846	pm_runtime_use_autosuspend(&pdev->dev);
847	pm_runtime_set_autosuspend_delay(&pdev->dev, UART_AUTOSUSPEND_TIMEOUT);
848	pm_runtime_set_active(&pdev->dev);
849	pm_runtime_enable(&pdev->dev);
850
851	ret = ulite_assign(&pdev->dev, id, res->start, irq, pdata);
852
853	pm_runtime_mark_last_busy(&pdev->dev);
854	pm_runtime_put_autosuspend(&pdev->dev);
855
856	return ret;
857}
858
859static int ulite_remove(struct platform_device *pdev)
860{
861	struct uart_port *port = dev_get_drvdata(&pdev->dev);
862	struct uartlite_data *pdata = port->private_data;
863	int rc;
864
865	clk_unprepare(pdata->clk);
866	rc = ulite_release(&pdev->dev);
867	pm_runtime_disable(&pdev->dev);
868	pm_runtime_set_suspended(&pdev->dev);
869	pm_runtime_dont_use_autosuspend(&pdev->dev);
870	return rc;
871}
872
873/* work with hotplug and coldplug */
874MODULE_ALIAS("platform:uartlite");
875
876static struct platform_driver ulite_platform_driver = {
877	.probe = ulite_probe,
878	.remove = ulite_remove,
879	.driver = {
 
880		.name  = "uartlite",
881		.of_match_table = of_match_ptr(ulite_of_match),
882		.pm = &ulite_pm_ops,
883	},
884};
885
886/* ---------------------------------------------------------------------
887 * Module setup/teardown
888 */
889
890static int __init ulite_init(void)
891{
 
 
 
 
 
 
892
893	pr_debug("uartlite: calling platform_driver_register()\n");
894	return platform_driver_register(&ulite_platform_driver);
 
 
 
 
 
 
 
 
 
 
895}
896
897static void __exit ulite_exit(void)
898{
899	platform_driver_unregister(&ulite_platform_driver);
900	if (ulite_uart_driver.state)
901		uart_unregister_driver(&ulite_uart_driver);
902}
903
904module_init(ulite_init);
905module_exit(ulite_exit);
906
907MODULE_AUTHOR("Peter Korsgaard <jacmet@sunsite.dk>");
908MODULE_DESCRIPTION("Xilinx uartlite serial driver");
909MODULE_LICENSE("GPL");
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");