xref: /openbmc/linux/drivers/tty/serial/lpc32xx_hs.c (revision cef69974)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * High Speed Serial Ports on NXP LPC32xx SoC
4  *
5  * Authors: Kevin Wells <kevin.wells@nxp.com>
6  *          Roland Stigge <stigge@antcom.de>
7  *
8  * Copyright (C) 2010 NXP Semiconductors
9  * Copyright (C) 2012 Roland Stigge
10  */
11 
12 #include <linux/module.h>
13 #include <linux/ioport.h>
14 #include <linux/init.h>
15 #include <linux/console.h>
16 #include <linux/sysrq.h>
17 #include <linux/tty.h>
18 #include <linux/tty_flip.h>
19 #include <linux/serial_core.h>
20 #include <linux/serial.h>
21 #include <linux/platform_device.h>
22 #include <linux/delay.h>
23 #include <linux/nmi.h>
24 #include <linux/io.h>
25 #include <linux/irq.h>
26 #include <linux/of.h>
27 #include <linux/sizes.h>
28 #include <linux/soc/nxp/lpc32xx-misc.h>
29 
30 /*
31  * High Speed UART register offsets
32  */
33 #define LPC32XX_HSUART_FIFO(x)			((x) + 0x00)
34 #define LPC32XX_HSUART_LEVEL(x)			((x) + 0x04)
35 #define LPC32XX_HSUART_IIR(x)			((x) + 0x08)
36 #define LPC32XX_HSUART_CTRL(x)			((x) + 0x0C)
37 #define LPC32XX_HSUART_RATE(x)			((x) + 0x10)
38 
39 #define LPC32XX_HSU_BREAK_DATA			(1 << 10)
40 #define LPC32XX_HSU_ERROR_DATA			(1 << 9)
41 #define LPC32XX_HSU_RX_EMPTY			(1 << 8)
42 
43 #define LPC32XX_HSU_TX_LEV(n)			(((n) >> 8) & 0xFF)
44 #define LPC32XX_HSU_RX_LEV(n)			((n) & 0xFF)
45 
46 #define LPC32XX_HSU_TX_INT_SET			(1 << 6)
47 #define LPC32XX_HSU_RX_OE_INT			(1 << 5)
48 #define LPC32XX_HSU_BRK_INT			(1 << 4)
49 #define LPC32XX_HSU_FE_INT			(1 << 3)
50 #define LPC32XX_HSU_RX_TIMEOUT_INT		(1 << 2)
51 #define LPC32XX_HSU_RX_TRIG_INT			(1 << 1)
52 #define LPC32XX_HSU_TX_INT			(1 << 0)
53 
54 #define LPC32XX_HSU_HRTS_INV			(1 << 21)
55 #define LPC32XX_HSU_HRTS_TRIG_8B		(0x0 << 19)
56 #define LPC32XX_HSU_HRTS_TRIG_16B		(0x1 << 19)
57 #define LPC32XX_HSU_HRTS_TRIG_32B		(0x2 << 19)
58 #define LPC32XX_HSU_HRTS_TRIG_48B		(0x3 << 19)
59 #define LPC32XX_HSU_HRTS_EN			(1 << 18)
60 #define LPC32XX_HSU_TMO_DISABLED		(0x0 << 16)
61 #define LPC32XX_HSU_TMO_INACT_4B		(0x1 << 16)
62 #define LPC32XX_HSU_TMO_INACT_8B		(0x2 << 16)
63 #define LPC32XX_HSU_TMO_INACT_16B		(0x3 << 16)
64 #define LPC32XX_HSU_HCTS_INV			(1 << 15)
65 #define LPC32XX_HSU_HCTS_EN			(1 << 14)
66 #define LPC32XX_HSU_OFFSET(n)			((n) << 9)
67 #define LPC32XX_HSU_BREAK			(1 << 8)
68 #define LPC32XX_HSU_ERR_INT_EN			(1 << 7)
69 #define LPC32XX_HSU_RX_INT_EN			(1 << 6)
70 #define LPC32XX_HSU_TX_INT_EN			(1 << 5)
71 #define LPC32XX_HSU_RX_TL1B			(0x0 << 2)
72 #define LPC32XX_HSU_RX_TL4B			(0x1 << 2)
73 #define LPC32XX_HSU_RX_TL8B			(0x2 << 2)
74 #define LPC32XX_HSU_RX_TL16B			(0x3 << 2)
75 #define LPC32XX_HSU_RX_TL32B			(0x4 << 2)
76 #define LPC32XX_HSU_RX_TL48B			(0x5 << 2)
77 #define LPC32XX_HSU_TX_TLEMPTY			(0x0 << 0)
78 #define LPC32XX_HSU_TX_TL0B			(0x0 << 0)
79 #define LPC32XX_HSU_TX_TL4B			(0x1 << 0)
80 #define LPC32XX_HSU_TX_TL8B			(0x2 << 0)
81 #define LPC32XX_HSU_TX_TL16B			(0x3 << 0)
82 
83 #define LPC32XX_MAIN_OSC_FREQ			13000000
84 
85 #define MODNAME "lpc32xx_hsuart"
86 
87 struct lpc32xx_hsuart_port {
88 	struct uart_port port;
89 };
90 
91 #define FIFO_READ_LIMIT 128
92 #define MAX_PORTS 3
93 #define LPC32XX_TTY_NAME "ttyTX"
94 static struct lpc32xx_hsuart_port lpc32xx_hs_ports[MAX_PORTS];
95 
96 #ifdef CONFIG_SERIAL_HS_LPC32XX_CONSOLE
97 static void wait_for_xmit_empty(struct uart_port *port)
98 {
99 	unsigned int timeout = 10000;
100 
101 	do {
102 		if (LPC32XX_HSU_TX_LEV(readl(LPC32XX_HSUART_LEVEL(
103 							port->membase))) == 0)
104 			break;
105 		if (--timeout == 0)
106 			break;
107 		udelay(1);
108 	} while (1);
109 }
110 
111 static void wait_for_xmit_ready(struct uart_port *port)
112 {
113 	unsigned int timeout = 10000;
114 
115 	while (1) {
116 		if (LPC32XX_HSU_TX_LEV(readl(LPC32XX_HSUART_LEVEL(
117 							port->membase))) < 32)
118 			break;
119 		if (--timeout == 0)
120 			break;
121 		udelay(1);
122 	}
123 }
124 
125 static void lpc32xx_hsuart_console_putchar(struct uart_port *port, unsigned char ch)
126 {
127 	wait_for_xmit_ready(port);
128 	writel((u32)ch, LPC32XX_HSUART_FIFO(port->membase));
129 }
130 
131 static void lpc32xx_hsuart_console_write(struct console *co, const char *s,
132 					 unsigned int count)
133 {
134 	struct lpc32xx_hsuart_port *up = &lpc32xx_hs_ports[co->index];
135 	unsigned long flags;
136 	int locked = 1;
137 
138 	touch_nmi_watchdog();
139 	local_irq_save(flags);
140 	if (up->port.sysrq)
141 		locked = 0;
142 	else if (oops_in_progress)
143 		locked = spin_trylock(&up->port.lock);
144 	else
145 		spin_lock(&up->port.lock);
146 
147 	uart_console_write(&up->port, s, count, lpc32xx_hsuart_console_putchar);
148 	wait_for_xmit_empty(&up->port);
149 
150 	if (locked)
151 		spin_unlock(&up->port.lock);
152 	local_irq_restore(flags);
153 }
154 
155 static int __init lpc32xx_hsuart_console_setup(struct console *co,
156 					       char *options)
157 {
158 	struct uart_port *port;
159 	int baud = 115200;
160 	int bits = 8;
161 	int parity = 'n';
162 	int flow = 'n';
163 
164 	if (co->index >= MAX_PORTS)
165 		co->index = 0;
166 
167 	port = &lpc32xx_hs_ports[co->index].port;
168 	if (!port->membase)
169 		return -ENODEV;
170 
171 	if (options)
172 		uart_parse_options(options, &baud, &parity, &bits, &flow);
173 
174 	lpc32xx_loopback_set(port->mapbase, 0); /* get out of loopback mode */
175 
176 	return uart_set_options(port, co, baud, parity, bits, flow);
177 }
178 
179 static struct uart_driver lpc32xx_hsuart_reg;
180 static struct console lpc32xx_hsuart_console = {
181 	.name		= LPC32XX_TTY_NAME,
182 	.write		= lpc32xx_hsuart_console_write,
183 	.device		= uart_console_device,
184 	.setup		= lpc32xx_hsuart_console_setup,
185 	.flags		= CON_PRINTBUFFER,
186 	.index		= -1,
187 	.data		= &lpc32xx_hsuart_reg,
188 };
189 
190 static int __init lpc32xx_hsuart_console_init(void)
191 {
192 	register_console(&lpc32xx_hsuart_console);
193 	return 0;
194 }
195 console_initcall(lpc32xx_hsuart_console_init);
196 
197 #define LPC32XX_HSUART_CONSOLE (&lpc32xx_hsuart_console)
198 #else
199 #define LPC32XX_HSUART_CONSOLE NULL
200 #endif
201 
202 static struct uart_driver lpc32xx_hs_reg = {
203 	.owner		= THIS_MODULE,
204 	.driver_name	= MODNAME,
205 	.dev_name	= LPC32XX_TTY_NAME,
206 	.nr		= MAX_PORTS,
207 	.cons		= LPC32XX_HSUART_CONSOLE,
208 };
209 static int uarts_registered;
210 
211 static unsigned int __serial_get_clock_div(unsigned long uartclk,
212 					   unsigned long rate)
213 {
214 	u32 div, goodrate, hsu_rate, l_hsu_rate, comprate;
215 	u32 rate_diff;
216 
217 	/* Find the closest divider to get the desired clock rate */
218 	div = uartclk / rate;
219 	goodrate = hsu_rate = (div / 14) - 1;
220 	if (hsu_rate != 0)
221 		hsu_rate--;
222 
223 	/* Tweak divider */
224 	l_hsu_rate = hsu_rate + 3;
225 	rate_diff = 0xFFFFFFFF;
226 
227 	while (hsu_rate < l_hsu_rate) {
228 		comprate = uartclk / ((hsu_rate + 1) * 14);
229 		if (abs(comprate - rate) < rate_diff) {
230 			goodrate = hsu_rate;
231 			rate_diff = abs(comprate - rate);
232 		}
233 
234 		hsu_rate++;
235 	}
236 	if (hsu_rate > 0xFF)
237 		hsu_rate = 0xFF;
238 
239 	return goodrate;
240 }
241 
242 static void __serial_uart_flush(struct uart_port *port)
243 {
244 	int cnt = 0;
245 
246 	while ((readl(LPC32XX_HSUART_LEVEL(port->membase)) > 0) &&
247 	       (cnt++ < FIFO_READ_LIMIT))
248 		readl(LPC32XX_HSUART_FIFO(port->membase));
249 }
250 
251 static void __serial_lpc32xx_rx(struct uart_port *port)
252 {
253 	struct tty_port *tport = &port->state->port;
254 	unsigned int tmp, flag;
255 
256 	/* Read data from FIFO and push into terminal */
257 	tmp = readl(LPC32XX_HSUART_FIFO(port->membase));
258 	while (!(tmp & LPC32XX_HSU_RX_EMPTY)) {
259 		flag = TTY_NORMAL;
260 		port->icount.rx++;
261 
262 		if (tmp & LPC32XX_HSU_ERROR_DATA) {
263 			/* Framing error */
264 			writel(LPC32XX_HSU_FE_INT,
265 			       LPC32XX_HSUART_IIR(port->membase));
266 			port->icount.frame++;
267 			flag = TTY_FRAME;
268 			tty_insert_flip_char(tport, 0, TTY_FRAME);
269 		}
270 
271 		tty_insert_flip_char(tport, (tmp & 0xFF), flag);
272 
273 		tmp = readl(LPC32XX_HSUART_FIFO(port->membase));
274 	}
275 
276 	tty_flip_buffer_push(tport);
277 }
278 
279 static void serial_lpc32xx_stop_tx(struct uart_port *port);
280 
281 static void __serial_lpc32xx_tx(struct uart_port *port)
282 {
283 	struct circ_buf *xmit = &port->state->xmit;
284 
285 	if (port->x_char) {
286 		writel((u32)port->x_char, LPC32XX_HSUART_FIFO(port->membase));
287 		port->icount.tx++;
288 		port->x_char = 0;
289 		return;
290 	}
291 
292 	if (uart_circ_empty(xmit) || uart_tx_stopped(port))
293 		goto exit_tx;
294 
295 	/* Transfer data */
296 	while (LPC32XX_HSU_TX_LEV(readl(
297 		LPC32XX_HSUART_LEVEL(port->membase))) < 64) {
298 		writel((u32) xmit->buf[xmit->tail],
299 		       LPC32XX_HSUART_FIFO(port->membase));
300 		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
301 		port->icount.tx++;
302 		if (uart_circ_empty(xmit))
303 			break;
304 	}
305 
306 	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
307 		uart_write_wakeup(port);
308 
309 exit_tx:
310 	if (uart_circ_empty(xmit))
311 		serial_lpc32xx_stop_tx(port);
312 }
313 
314 static irqreturn_t serial_lpc32xx_interrupt(int irq, void *dev_id)
315 {
316 	struct uart_port *port = dev_id;
317 	struct tty_port *tport = &port->state->port;
318 	u32 status;
319 
320 	spin_lock(&port->lock);
321 
322 	/* Read UART status and clear latched interrupts */
323 	status = readl(LPC32XX_HSUART_IIR(port->membase));
324 
325 	if (status & LPC32XX_HSU_BRK_INT) {
326 		/* Break received */
327 		writel(LPC32XX_HSU_BRK_INT, LPC32XX_HSUART_IIR(port->membase));
328 		port->icount.brk++;
329 		uart_handle_break(port);
330 	}
331 
332 	/* Framing error */
333 	if (status & LPC32XX_HSU_FE_INT)
334 		writel(LPC32XX_HSU_FE_INT, LPC32XX_HSUART_IIR(port->membase));
335 
336 	if (status & LPC32XX_HSU_RX_OE_INT) {
337 		/* Receive FIFO overrun */
338 		writel(LPC32XX_HSU_RX_OE_INT,
339 		       LPC32XX_HSUART_IIR(port->membase));
340 		port->icount.overrun++;
341 		tty_insert_flip_char(tport, 0, TTY_OVERRUN);
342 		tty_flip_buffer_push(tport);
343 	}
344 
345 	/* Data received? */
346 	if (status & (LPC32XX_HSU_RX_TIMEOUT_INT | LPC32XX_HSU_RX_TRIG_INT))
347 		__serial_lpc32xx_rx(port);
348 
349 	/* Transmit data request? */
350 	if ((status & LPC32XX_HSU_TX_INT) && (!uart_tx_stopped(port))) {
351 		writel(LPC32XX_HSU_TX_INT, LPC32XX_HSUART_IIR(port->membase));
352 		__serial_lpc32xx_tx(port);
353 	}
354 
355 	spin_unlock(&port->lock);
356 
357 	return IRQ_HANDLED;
358 }
359 
360 /* port->lock is not held.  */
361 static unsigned int serial_lpc32xx_tx_empty(struct uart_port *port)
362 {
363 	unsigned int ret = 0;
364 
365 	if (LPC32XX_HSU_TX_LEV(readl(LPC32XX_HSUART_LEVEL(port->membase))) == 0)
366 		ret = TIOCSER_TEMT;
367 
368 	return ret;
369 }
370 
371 /* port->lock held by caller.  */
372 static void serial_lpc32xx_set_mctrl(struct uart_port *port,
373 				     unsigned int mctrl)
374 {
375 	/* No signals are supported on HS UARTs */
376 }
377 
378 /* port->lock is held by caller and interrupts are disabled.  */
379 static unsigned int serial_lpc32xx_get_mctrl(struct uart_port *port)
380 {
381 	/* No signals are supported on HS UARTs */
382 	return TIOCM_CAR | TIOCM_DSR | TIOCM_CTS;
383 }
384 
385 /* port->lock held by caller.  */
386 static void serial_lpc32xx_stop_tx(struct uart_port *port)
387 {
388 	u32 tmp;
389 
390 	tmp = readl(LPC32XX_HSUART_CTRL(port->membase));
391 	tmp &= ~LPC32XX_HSU_TX_INT_EN;
392 	writel(tmp, LPC32XX_HSUART_CTRL(port->membase));
393 }
394 
395 /* port->lock held by caller.  */
396 static void serial_lpc32xx_start_tx(struct uart_port *port)
397 {
398 	u32 tmp;
399 
400 	__serial_lpc32xx_tx(port);
401 	tmp = readl(LPC32XX_HSUART_CTRL(port->membase));
402 	tmp |= LPC32XX_HSU_TX_INT_EN;
403 	writel(tmp, LPC32XX_HSUART_CTRL(port->membase));
404 }
405 
406 /* port->lock held by caller.  */
407 static void serial_lpc32xx_stop_rx(struct uart_port *port)
408 {
409 	u32 tmp;
410 
411 	tmp = readl(LPC32XX_HSUART_CTRL(port->membase));
412 	tmp &= ~(LPC32XX_HSU_RX_INT_EN | LPC32XX_HSU_ERR_INT_EN);
413 	writel(tmp, LPC32XX_HSUART_CTRL(port->membase));
414 
415 	writel((LPC32XX_HSU_BRK_INT | LPC32XX_HSU_RX_OE_INT |
416 		LPC32XX_HSU_FE_INT), LPC32XX_HSUART_IIR(port->membase));
417 }
418 
419 /* port->lock is not held.  */
420 static void serial_lpc32xx_break_ctl(struct uart_port *port,
421 				     int break_state)
422 {
423 	unsigned long flags;
424 	u32 tmp;
425 
426 	spin_lock_irqsave(&port->lock, flags);
427 	tmp = readl(LPC32XX_HSUART_CTRL(port->membase));
428 	if (break_state != 0)
429 		tmp |= LPC32XX_HSU_BREAK;
430 	else
431 		tmp &= ~LPC32XX_HSU_BREAK;
432 	writel(tmp, LPC32XX_HSUART_CTRL(port->membase));
433 	spin_unlock_irqrestore(&port->lock, flags);
434 }
435 
436 /* port->lock is not held.  */
437 static int serial_lpc32xx_startup(struct uart_port *port)
438 {
439 	int retval;
440 	unsigned long flags;
441 	u32 tmp;
442 
443 	spin_lock_irqsave(&port->lock, flags);
444 
445 	__serial_uart_flush(port);
446 
447 	writel((LPC32XX_HSU_TX_INT | LPC32XX_HSU_FE_INT |
448 		LPC32XX_HSU_BRK_INT | LPC32XX_HSU_RX_OE_INT),
449 	       LPC32XX_HSUART_IIR(port->membase));
450 
451 	writel(0xFF, LPC32XX_HSUART_RATE(port->membase));
452 
453 	/*
454 	 * Set receiver timeout, HSU offset of 20, no break, no interrupts,
455 	 * and default FIFO trigger levels
456 	 */
457 	tmp = LPC32XX_HSU_TX_TL8B | LPC32XX_HSU_RX_TL32B |
458 		LPC32XX_HSU_OFFSET(20) | LPC32XX_HSU_TMO_INACT_4B;
459 	writel(tmp, LPC32XX_HSUART_CTRL(port->membase));
460 
461 	lpc32xx_loopback_set(port->mapbase, 0); /* get out of loopback mode */
462 
463 	spin_unlock_irqrestore(&port->lock, flags);
464 
465 	retval = request_irq(port->irq, serial_lpc32xx_interrupt,
466 			     0, MODNAME, port);
467 	if (!retval)
468 		writel((tmp | LPC32XX_HSU_RX_INT_EN | LPC32XX_HSU_ERR_INT_EN),
469 		       LPC32XX_HSUART_CTRL(port->membase));
470 
471 	return retval;
472 }
473 
474 /* port->lock is not held.  */
475 static void serial_lpc32xx_shutdown(struct uart_port *port)
476 {
477 	u32 tmp;
478 	unsigned long flags;
479 
480 	spin_lock_irqsave(&port->lock, flags);
481 
482 	tmp = LPC32XX_HSU_TX_TL8B | LPC32XX_HSU_RX_TL32B |
483 		LPC32XX_HSU_OFFSET(20) | LPC32XX_HSU_TMO_INACT_4B;
484 	writel(tmp, LPC32XX_HSUART_CTRL(port->membase));
485 
486 	lpc32xx_loopback_set(port->mapbase, 1); /* go to loopback mode */
487 
488 	spin_unlock_irqrestore(&port->lock, flags);
489 
490 	free_irq(port->irq, port);
491 }
492 
493 /* port->lock is not held.  */
494 static void serial_lpc32xx_set_termios(struct uart_port *port,
495 				       struct ktermios *termios,
496 				       struct ktermios *old)
497 {
498 	unsigned long flags;
499 	unsigned int baud, quot;
500 	u32 tmp;
501 
502 	/* Always 8-bit, no parity, 1 stop bit */
503 	termios->c_cflag &= ~(CSIZE | CSTOPB | PARENB | PARODD);
504 	termios->c_cflag |= CS8;
505 
506 	termios->c_cflag &= ~(HUPCL | CMSPAR | CLOCAL | CRTSCTS);
507 
508 	baud = uart_get_baud_rate(port, termios, old, 0,
509 				  port->uartclk / 14);
510 
511 	quot = __serial_get_clock_div(port->uartclk, baud);
512 
513 	spin_lock_irqsave(&port->lock, flags);
514 
515 	/* Ignore characters? */
516 	tmp = readl(LPC32XX_HSUART_CTRL(port->membase));
517 	if ((termios->c_cflag & CREAD) == 0)
518 		tmp &= ~(LPC32XX_HSU_RX_INT_EN | LPC32XX_HSU_ERR_INT_EN);
519 	else
520 		tmp |= LPC32XX_HSU_RX_INT_EN | LPC32XX_HSU_ERR_INT_EN;
521 	writel(tmp, LPC32XX_HSUART_CTRL(port->membase));
522 
523 	writel(quot, LPC32XX_HSUART_RATE(port->membase));
524 
525 	uart_update_timeout(port, termios->c_cflag, baud);
526 
527 	spin_unlock_irqrestore(&port->lock, flags);
528 
529 	/* Don't rewrite B0 */
530 	if (tty_termios_baud_rate(termios))
531 		tty_termios_encode_baud_rate(termios, baud, baud);
532 }
533 
534 static const char *serial_lpc32xx_type(struct uart_port *port)
535 {
536 	return MODNAME;
537 }
538 
539 static void serial_lpc32xx_release_port(struct uart_port *port)
540 {
541 	if ((port->iotype == UPIO_MEM32) && (port->mapbase)) {
542 		if (port->flags & UPF_IOREMAP) {
543 			iounmap(port->membase);
544 			port->membase = NULL;
545 		}
546 
547 		release_mem_region(port->mapbase, SZ_4K);
548 	}
549 }
550 
551 static int serial_lpc32xx_request_port(struct uart_port *port)
552 {
553 	int ret = -ENODEV;
554 
555 	if ((port->iotype == UPIO_MEM32) && (port->mapbase)) {
556 		ret = 0;
557 
558 		if (!request_mem_region(port->mapbase, SZ_4K, MODNAME))
559 			ret = -EBUSY;
560 		else if (port->flags & UPF_IOREMAP) {
561 			port->membase = ioremap(port->mapbase, SZ_4K);
562 			if (!port->membase) {
563 				release_mem_region(port->mapbase, SZ_4K);
564 				ret = -ENOMEM;
565 			}
566 		}
567 	}
568 
569 	return ret;
570 }
571 
572 static void serial_lpc32xx_config_port(struct uart_port *port, int uflags)
573 {
574 	int ret;
575 
576 	ret = serial_lpc32xx_request_port(port);
577 	if (ret < 0)
578 		return;
579 	port->type = PORT_UART00;
580 	port->fifosize = 64;
581 
582 	__serial_uart_flush(port);
583 
584 	writel((LPC32XX_HSU_TX_INT | LPC32XX_HSU_FE_INT |
585 		LPC32XX_HSU_BRK_INT | LPC32XX_HSU_RX_OE_INT),
586 	       LPC32XX_HSUART_IIR(port->membase));
587 
588 	writel(0xFF, LPC32XX_HSUART_RATE(port->membase));
589 
590 	/* Set receiver timeout, HSU offset of 20, no break, no interrupts,
591 	   and default FIFO trigger levels */
592 	writel(LPC32XX_HSU_TX_TL8B | LPC32XX_HSU_RX_TL32B |
593 	       LPC32XX_HSU_OFFSET(20) | LPC32XX_HSU_TMO_INACT_4B,
594 	       LPC32XX_HSUART_CTRL(port->membase));
595 }
596 
597 static int serial_lpc32xx_verify_port(struct uart_port *port,
598 				      struct serial_struct *ser)
599 {
600 	int ret = 0;
601 
602 	if (ser->type != PORT_UART00)
603 		ret = -EINVAL;
604 
605 	return ret;
606 }
607 
608 static const struct uart_ops serial_lpc32xx_pops = {
609 	.tx_empty	= serial_lpc32xx_tx_empty,
610 	.set_mctrl	= serial_lpc32xx_set_mctrl,
611 	.get_mctrl	= serial_lpc32xx_get_mctrl,
612 	.stop_tx	= serial_lpc32xx_stop_tx,
613 	.start_tx	= serial_lpc32xx_start_tx,
614 	.stop_rx	= serial_lpc32xx_stop_rx,
615 	.break_ctl	= serial_lpc32xx_break_ctl,
616 	.startup	= serial_lpc32xx_startup,
617 	.shutdown	= serial_lpc32xx_shutdown,
618 	.set_termios	= serial_lpc32xx_set_termios,
619 	.type		= serial_lpc32xx_type,
620 	.release_port	= serial_lpc32xx_release_port,
621 	.request_port	= serial_lpc32xx_request_port,
622 	.config_port	= serial_lpc32xx_config_port,
623 	.verify_port	= serial_lpc32xx_verify_port,
624 };
625 
626 /*
627  * Register a set of serial devices attached to a platform device
628  */
629 static int serial_hs_lpc32xx_probe(struct platform_device *pdev)
630 {
631 	struct lpc32xx_hsuart_port *p = &lpc32xx_hs_ports[uarts_registered];
632 	int ret = 0;
633 	struct resource *res;
634 
635 	if (uarts_registered >= MAX_PORTS) {
636 		dev_err(&pdev->dev,
637 			"Error: Number of possible ports exceeded (%d)!\n",
638 			uarts_registered + 1);
639 		return -ENXIO;
640 	}
641 
642 	memset(p, 0, sizeof(*p));
643 
644 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
645 	if (!res) {
646 		dev_err(&pdev->dev,
647 			"Error getting mem resource for HS UART port %d\n",
648 			uarts_registered);
649 		return -ENXIO;
650 	}
651 	p->port.mapbase = res->start;
652 	p->port.membase = NULL;
653 
654 	ret = platform_get_irq(pdev, 0);
655 	if (ret < 0)
656 		return ret;
657 	p->port.irq = ret;
658 
659 	p->port.iotype = UPIO_MEM32;
660 	p->port.uartclk = LPC32XX_MAIN_OSC_FREQ;
661 	p->port.regshift = 2;
662 	p->port.flags = UPF_BOOT_AUTOCONF | UPF_FIXED_PORT | UPF_IOREMAP;
663 	p->port.dev = &pdev->dev;
664 	p->port.ops = &serial_lpc32xx_pops;
665 	p->port.line = uarts_registered++;
666 	spin_lock_init(&p->port.lock);
667 
668 	/* send port to loopback mode by default */
669 	lpc32xx_loopback_set(p->port.mapbase, 1);
670 
671 	ret = uart_add_one_port(&lpc32xx_hs_reg, &p->port);
672 
673 	platform_set_drvdata(pdev, p);
674 
675 	return ret;
676 }
677 
678 /*
679  * Remove serial ports registered against a platform device.
680  */
681 static int serial_hs_lpc32xx_remove(struct platform_device *pdev)
682 {
683 	struct lpc32xx_hsuart_port *p = platform_get_drvdata(pdev);
684 
685 	uart_remove_one_port(&lpc32xx_hs_reg, &p->port);
686 
687 	return 0;
688 }
689 
690 
691 #ifdef CONFIG_PM
692 static int serial_hs_lpc32xx_suspend(struct platform_device *pdev,
693 				     pm_message_t state)
694 {
695 	struct lpc32xx_hsuart_port *p = platform_get_drvdata(pdev);
696 
697 	uart_suspend_port(&lpc32xx_hs_reg, &p->port);
698 
699 	return 0;
700 }
701 
702 static int serial_hs_lpc32xx_resume(struct platform_device *pdev)
703 {
704 	struct lpc32xx_hsuart_port *p = platform_get_drvdata(pdev);
705 
706 	uart_resume_port(&lpc32xx_hs_reg, &p->port);
707 
708 	return 0;
709 }
710 #else
711 #define serial_hs_lpc32xx_suspend	NULL
712 #define serial_hs_lpc32xx_resume	NULL
713 #endif
714 
715 static const struct of_device_id serial_hs_lpc32xx_dt_ids[] = {
716 	{ .compatible = "nxp,lpc3220-hsuart" },
717 	{ /* sentinel */ }
718 };
719 
720 MODULE_DEVICE_TABLE(of, serial_hs_lpc32xx_dt_ids);
721 
722 static struct platform_driver serial_hs_lpc32xx_driver = {
723 	.probe		= serial_hs_lpc32xx_probe,
724 	.remove		= serial_hs_lpc32xx_remove,
725 	.suspend	= serial_hs_lpc32xx_suspend,
726 	.resume		= serial_hs_lpc32xx_resume,
727 	.driver		= {
728 		.name	= MODNAME,
729 		.of_match_table	= serial_hs_lpc32xx_dt_ids,
730 	},
731 };
732 
733 static int __init lpc32xx_hsuart_init(void)
734 {
735 	int ret;
736 
737 	ret = uart_register_driver(&lpc32xx_hs_reg);
738 	if (ret)
739 		return ret;
740 
741 	ret = platform_driver_register(&serial_hs_lpc32xx_driver);
742 	if (ret)
743 		uart_unregister_driver(&lpc32xx_hs_reg);
744 
745 	return ret;
746 }
747 
748 static void __exit lpc32xx_hsuart_exit(void)
749 {
750 	platform_driver_unregister(&serial_hs_lpc32xx_driver);
751 	uart_unregister_driver(&lpc32xx_hs_reg);
752 }
753 
754 module_init(lpc32xx_hsuart_init);
755 module_exit(lpc32xx_hsuart_exit);
756 
757 MODULE_AUTHOR("Kevin Wells <kevin.wells@nxp.com>");
758 MODULE_AUTHOR("Roland Stigge <stigge@antcom.de>");
759 MODULE_DESCRIPTION("NXP LPC32XX High Speed UART driver");
760 MODULE_LICENSE("GPL");
761