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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/gpio.h>
27#include <linux/of.h>
28#include <linux/sizes.h>
29#include <linux/soc/nxp/lpc32xx-misc.h>
30
31/*
32 * High Speed UART register offsets
33 */
34#define LPC32XX_HSUART_FIFO(x) ((x) + 0x00)
35#define LPC32XX_HSUART_LEVEL(x) ((x) + 0x04)
36#define LPC32XX_HSUART_IIR(x) ((x) + 0x08)
37#define LPC32XX_HSUART_CTRL(x) ((x) + 0x0C)
38#define LPC32XX_HSUART_RATE(x) ((x) + 0x10)
39
40#define LPC32XX_HSU_BREAK_DATA (1 << 10)
41#define LPC32XX_HSU_ERROR_DATA (1 << 9)
42#define LPC32XX_HSU_RX_EMPTY (1 << 8)
43
44#define LPC32XX_HSU_TX_LEV(n) (((n) >> 8) & 0xFF)
45#define LPC32XX_HSU_RX_LEV(n) ((n) & 0xFF)
46
47#define LPC32XX_HSU_TX_INT_SET (1 << 6)
48#define LPC32XX_HSU_RX_OE_INT (1 << 5)
49#define LPC32XX_HSU_BRK_INT (1 << 4)
50#define LPC32XX_HSU_FE_INT (1 << 3)
51#define LPC32XX_HSU_RX_TIMEOUT_INT (1 << 2)
52#define LPC32XX_HSU_RX_TRIG_INT (1 << 1)
53#define LPC32XX_HSU_TX_INT (1 << 0)
54
55#define LPC32XX_HSU_HRTS_INV (1 << 21)
56#define LPC32XX_HSU_HRTS_TRIG_8B (0x0 << 19)
57#define LPC32XX_HSU_HRTS_TRIG_16B (0x1 << 19)
58#define LPC32XX_HSU_HRTS_TRIG_32B (0x2 << 19)
59#define LPC32XX_HSU_HRTS_TRIG_48B (0x3 << 19)
60#define LPC32XX_HSU_HRTS_EN (1 << 18)
61#define LPC32XX_HSU_TMO_DISABLED (0x0 << 16)
62#define LPC32XX_HSU_TMO_INACT_4B (0x1 << 16)
63#define LPC32XX_HSU_TMO_INACT_8B (0x2 << 16)
64#define LPC32XX_HSU_TMO_INACT_16B (0x3 << 16)
65#define LPC32XX_HSU_HCTS_INV (1 << 15)
66#define LPC32XX_HSU_HCTS_EN (1 << 14)
67#define LPC32XX_HSU_OFFSET(n) ((n) << 9)
68#define LPC32XX_HSU_BREAK (1 << 8)
69#define LPC32XX_HSU_ERR_INT_EN (1 << 7)
70#define LPC32XX_HSU_RX_INT_EN (1 << 6)
71#define LPC32XX_HSU_TX_INT_EN (1 << 5)
72#define LPC32XX_HSU_RX_TL1B (0x0 << 2)
73#define LPC32XX_HSU_RX_TL4B (0x1 << 2)
74#define LPC32XX_HSU_RX_TL8B (0x2 << 2)
75#define LPC32XX_HSU_RX_TL16B (0x3 << 2)
76#define LPC32XX_HSU_RX_TL32B (0x4 << 2)
77#define LPC32XX_HSU_RX_TL48B (0x5 << 2)
78#define LPC32XX_HSU_TX_TLEMPTY (0x0 << 0)
79#define LPC32XX_HSU_TX_TL0B (0x0 << 0)
80#define LPC32XX_HSU_TX_TL4B (0x1 << 0)
81#define LPC32XX_HSU_TX_TL8B (0x2 << 0)
82#define LPC32XX_HSU_TX_TL16B (0x3 << 0)
83
84#define LPC32XX_MAIN_OSC_FREQ 13000000
85
86#define MODNAME "lpc32xx_hsuart"
87
88struct lpc32xx_hsuart_port {
89 struct uart_port port;
90};
91
92#define FIFO_READ_LIMIT 128
93#define MAX_PORTS 3
94#define LPC32XX_TTY_NAME "ttyTX"
95static struct lpc32xx_hsuart_port lpc32xx_hs_ports[MAX_PORTS];
96
97#ifdef CONFIG_SERIAL_HS_LPC32XX_CONSOLE
98static void wait_for_xmit_empty(struct uart_port *port)
99{
100 unsigned int timeout = 10000;
101
102 do {
103 if (LPC32XX_HSU_TX_LEV(readl(LPC32XX_HSUART_LEVEL(
104 port->membase))) == 0)
105 break;
106 if (--timeout == 0)
107 break;
108 udelay(1);
109 } while (1);
110}
111
112static void wait_for_xmit_ready(struct uart_port *port)
113{
114 unsigned int timeout = 10000;
115
116 while (1) {
117 if (LPC32XX_HSU_TX_LEV(readl(LPC32XX_HSUART_LEVEL(
118 port->membase))) < 32)
119 break;
120 if (--timeout == 0)
121 break;
122 udelay(1);
123 }
124}
125
126static void lpc32xx_hsuart_console_putchar(struct uart_port *port, int ch)
127{
128 wait_for_xmit_ready(port);
129 writel((u32)ch, LPC32XX_HSUART_FIFO(port->membase));
130}
131
132static void lpc32xx_hsuart_console_write(struct console *co, const char *s,
133 unsigned int count)
134{
135 struct lpc32xx_hsuart_port *up = &lpc32xx_hs_ports[co->index];
136 unsigned long flags;
137 int locked = 1;
138
139 touch_nmi_watchdog();
140 local_irq_save(flags);
141 if (up->port.sysrq)
142 locked = 0;
143 else if (oops_in_progress)
144 locked = spin_trylock(&up->port.lock);
145 else
146 spin_lock(&up->port.lock);
147
148 uart_console_write(&up->port, s, count, lpc32xx_hsuart_console_putchar);
149 wait_for_xmit_empty(&up->port);
150
151 if (locked)
152 spin_unlock(&up->port.lock);
153 local_irq_restore(flags);
154}
155
156static int __init lpc32xx_hsuart_console_setup(struct console *co,
157 char *options)
158{
159 struct uart_port *port;
160 int baud = 115200;
161 int bits = 8;
162 int parity = 'n';
163 int flow = 'n';
164
165 if (co->index >= MAX_PORTS)
166 co->index = 0;
167
168 port = &lpc32xx_hs_ports[co->index].port;
169 if (!port->membase)
170 return -ENODEV;
171
172 if (options)
173 uart_parse_options(options, &baud, &parity, &bits, &flow);
174
175 lpc32xx_loopback_set(port->mapbase, 0); /* get out of loopback mode */
176
177 return uart_set_options(port, co, baud, parity, bits, flow);
178}
179
180static struct uart_driver lpc32xx_hsuart_reg;
181static struct console lpc32xx_hsuart_console = {
182 .name = LPC32XX_TTY_NAME,
183 .write = lpc32xx_hsuart_console_write,
184 .device = uart_console_device,
185 .setup = lpc32xx_hsuart_console_setup,
186 .flags = CON_PRINTBUFFER,
187 .index = -1,
188 .data = &lpc32xx_hsuart_reg,
189};
190
191static int __init lpc32xx_hsuart_console_init(void)
192{
193 register_console(&lpc32xx_hsuart_console);
194 return 0;
195}
196console_initcall(lpc32xx_hsuart_console_init);
197
198#define LPC32XX_HSUART_CONSOLE (&lpc32xx_hsuart_console)
199#else
200#define LPC32XX_HSUART_CONSOLE NULL
201#endif
202
203static struct uart_driver lpc32xx_hs_reg = {
204 .owner = THIS_MODULE,
205 .driver_name = MODNAME,
206 .dev_name = LPC32XX_TTY_NAME,
207 .nr = MAX_PORTS,
208 .cons = LPC32XX_HSUART_CONSOLE,
209};
210static int uarts_registered;
211
212static unsigned int __serial_get_clock_div(unsigned long uartclk,
213 unsigned long rate)
214{
215 u32 div, goodrate, hsu_rate, l_hsu_rate, comprate;
216 u32 rate_diff;
217
218 /* Find the closest divider to get the desired clock rate */
219 div = uartclk / rate;
220 goodrate = hsu_rate = (div / 14) - 1;
221 if (hsu_rate != 0)
222 hsu_rate--;
223
224 /* Tweak divider */
225 l_hsu_rate = hsu_rate + 3;
226 rate_diff = 0xFFFFFFFF;
227
228 while (hsu_rate < l_hsu_rate) {
229 comprate = uartclk / ((hsu_rate + 1) * 14);
230 if (abs(comprate - rate) < rate_diff) {
231 goodrate = hsu_rate;
232 rate_diff = abs(comprate - rate);
233 }
234
235 hsu_rate++;
236 }
237 if (hsu_rate > 0xFF)
238 hsu_rate = 0xFF;
239
240 return goodrate;
241}
242
243static void __serial_uart_flush(struct uart_port *port)
244{
245 u32 tmp;
246 int cnt = 0;
247
248 while ((readl(LPC32XX_HSUART_LEVEL(port->membase)) > 0) &&
249 (cnt++ < FIFO_READ_LIMIT))
250 tmp = readl(LPC32XX_HSUART_FIFO(port->membase));
251}
252
253static void __serial_lpc32xx_rx(struct uart_port *port)
254{
255 struct tty_port *tport = &port->state->port;
256 unsigned int tmp, flag;
257
258 /* Read data from FIFO and push into terminal */
259 tmp = readl(LPC32XX_HSUART_FIFO(port->membase));
260 while (!(tmp & LPC32XX_HSU_RX_EMPTY)) {
261 flag = TTY_NORMAL;
262 port->icount.rx++;
263
264 if (tmp & LPC32XX_HSU_ERROR_DATA) {
265 /* Framing error */
266 writel(LPC32XX_HSU_FE_INT,
267 LPC32XX_HSUART_IIR(port->membase));
268 port->icount.frame++;
269 flag = TTY_FRAME;
270 tty_insert_flip_char(tport, 0, TTY_FRAME);
271 }
272
273 tty_insert_flip_char(tport, (tmp & 0xFF), flag);
274
275 tmp = readl(LPC32XX_HSUART_FIFO(port->membase));
276 }
277
278 spin_unlock(&port->lock);
279 tty_flip_buffer_push(tport);
280 spin_lock(&port->lock);
281}
282
283static void __serial_lpc32xx_tx(struct uart_port *port)
284{
285 struct circ_buf *xmit = &port->state->xmit;
286 unsigned int tmp;
287
288 if (port->x_char) {
289 writel((u32)port->x_char, LPC32XX_HSUART_FIFO(port->membase));
290 port->icount.tx++;
291 port->x_char = 0;
292 return;
293 }
294
295 if (uart_circ_empty(xmit) || uart_tx_stopped(port))
296 goto exit_tx;
297
298 /* Transfer data */
299 while (LPC32XX_HSU_TX_LEV(readl(
300 LPC32XX_HSUART_LEVEL(port->membase))) < 64) {
301 writel((u32) xmit->buf[xmit->tail],
302 LPC32XX_HSUART_FIFO(port->membase));
303 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
304 port->icount.tx++;
305 if (uart_circ_empty(xmit))
306 break;
307 }
308
309 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
310 uart_write_wakeup(port);
311
312exit_tx:
313 if (uart_circ_empty(xmit)) {
314 tmp = readl(LPC32XX_HSUART_CTRL(port->membase));
315 tmp &= ~LPC32XX_HSU_TX_INT_EN;
316 writel(tmp, LPC32XX_HSUART_CTRL(port->membase));
317 }
318}
319
320static irqreturn_t serial_lpc32xx_interrupt(int irq, void *dev_id)
321{
322 struct uart_port *port = dev_id;
323 struct tty_port *tport = &port->state->port;
324 u32 status;
325
326 spin_lock(&port->lock);
327
328 /* Read UART status and clear latched interrupts */
329 status = readl(LPC32XX_HSUART_IIR(port->membase));
330
331 if (status & LPC32XX_HSU_BRK_INT) {
332 /* Break received */
333 writel(LPC32XX_HSU_BRK_INT, LPC32XX_HSUART_IIR(port->membase));
334 port->icount.brk++;
335 uart_handle_break(port);
336 }
337
338 /* Framing error */
339 if (status & LPC32XX_HSU_FE_INT)
340 writel(LPC32XX_HSU_FE_INT, LPC32XX_HSUART_IIR(port->membase));
341
342 if (status & LPC32XX_HSU_RX_OE_INT) {
343 /* Receive FIFO overrun */
344 writel(LPC32XX_HSU_RX_OE_INT,
345 LPC32XX_HSUART_IIR(port->membase));
346 port->icount.overrun++;
347 tty_insert_flip_char(tport, 0, TTY_OVERRUN);
348 tty_schedule_flip(tport);
349 }
350
351 /* Data received? */
352 if (status & (LPC32XX_HSU_RX_TIMEOUT_INT | LPC32XX_HSU_RX_TRIG_INT))
353 __serial_lpc32xx_rx(port);
354
355 /* Transmit data request? */
356 if ((status & LPC32XX_HSU_TX_INT) && (!uart_tx_stopped(port))) {
357 writel(LPC32XX_HSU_TX_INT, LPC32XX_HSUART_IIR(port->membase));
358 __serial_lpc32xx_tx(port);
359 }
360
361 spin_unlock(&port->lock);
362
363 return IRQ_HANDLED;
364}
365
366/* port->lock is not held. */
367static unsigned int serial_lpc32xx_tx_empty(struct uart_port *port)
368{
369 unsigned int ret = 0;
370
371 if (LPC32XX_HSU_TX_LEV(readl(LPC32XX_HSUART_LEVEL(port->membase))) == 0)
372 ret = TIOCSER_TEMT;
373
374 return ret;
375}
376
377/* port->lock held by caller. */
378static void serial_lpc32xx_set_mctrl(struct uart_port *port,
379 unsigned int mctrl)
380{
381 /* No signals are supported on HS UARTs */
382}
383
384/* port->lock is held by caller and interrupts are disabled. */
385static unsigned int serial_lpc32xx_get_mctrl(struct uart_port *port)
386{
387 /* No signals are supported on HS UARTs */
388 return TIOCM_CAR | TIOCM_DSR | TIOCM_CTS;
389}
390
391/* port->lock held by caller. */
392static void serial_lpc32xx_stop_tx(struct uart_port *port)
393{
394 u32 tmp;
395
396 tmp = readl(LPC32XX_HSUART_CTRL(port->membase));
397 tmp &= ~LPC32XX_HSU_TX_INT_EN;
398 writel(tmp, LPC32XX_HSUART_CTRL(port->membase));
399}
400
401/* port->lock held by caller. */
402static void serial_lpc32xx_start_tx(struct uart_port *port)
403{
404 u32 tmp;
405
406 __serial_lpc32xx_tx(port);
407 tmp = readl(LPC32XX_HSUART_CTRL(port->membase));
408 tmp |= LPC32XX_HSU_TX_INT_EN;
409 writel(tmp, LPC32XX_HSUART_CTRL(port->membase));
410}
411
412/* port->lock held by caller. */
413static void serial_lpc32xx_stop_rx(struct uart_port *port)
414{
415 u32 tmp;
416
417 tmp = readl(LPC32XX_HSUART_CTRL(port->membase));
418 tmp &= ~(LPC32XX_HSU_RX_INT_EN | LPC32XX_HSU_ERR_INT_EN);
419 writel(tmp, LPC32XX_HSUART_CTRL(port->membase));
420
421 writel((LPC32XX_HSU_BRK_INT | LPC32XX_HSU_RX_OE_INT |
422 LPC32XX_HSU_FE_INT), LPC32XX_HSUART_IIR(port->membase));
423}
424
425/* port->lock is not held. */
426static void serial_lpc32xx_break_ctl(struct uart_port *port,
427 int break_state)
428{
429 unsigned long flags;
430 u32 tmp;
431
432 spin_lock_irqsave(&port->lock, flags);
433 tmp = readl(LPC32XX_HSUART_CTRL(port->membase));
434 if (break_state != 0)
435 tmp |= LPC32XX_HSU_BREAK;
436 else
437 tmp &= ~LPC32XX_HSU_BREAK;
438 writel(tmp, LPC32XX_HSUART_CTRL(port->membase));
439 spin_unlock_irqrestore(&port->lock, flags);
440}
441
442/* port->lock is not held. */
443static int serial_lpc32xx_startup(struct uart_port *port)
444{
445 int retval;
446 unsigned long flags;
447 u32 tmp;
448
449 spin_lock_irqsave(&port->lock, flags);
450
451 __serial_uart_flush(port);
452
453 writel((LPC32XX_HSU_TX_INT | LPC32XX_HSU_FE_INT |
454 LPC32XX_HSU_BRK_INT | LPC32XX_HSU_RX_OE_INT),
455 LPC32XX_HSUART_IIR(port->membase));
456
457 writel(0xFF, LPC32XX_HSUART_RATE(port->membase));
458
459 /*
460 * Set receiver timeout, HSU offset of 20, no break, no interrupts,
461 * and default FIFO trigger levels
462 */
463 tmp = LPC32XX_HSU_TX_TL8B | LPC32XX_HSU_RX_TL32B |
464 LPC32XX_HSU_OFFSET(20) | LPC32XX_HSU_TMO_INACT_4B;
465 writel(tmp, LPC32XX_HSUART_CTRL(port->membase));
466
467 lpc32xx_loopback_set(port->mapbase, 0); /* get out of loopback mode */
468
469 spin_unlock_irqrestore(&port->lock, flags);
470
471 retval = request_irq(port->irq, serial_lpc32xx_interrupt,
472 0, MODNAME, port);
473 if (!retval)
474 writel((tmp | LPC32XX_HSU_RX_INT_EN | LPC32XX_HSU_ERR_INT_EN),
475 LPC32XX_HSUART_CTRL(port->membase));
476
477 return retval;
478}
479
480/* port->lock is not held. */
481static void serial_lpc32xx_shutdown(struct uart_port *port)
482{
483 u32 tmp;
484 unsigned long flags;
485
486 spin_lock_irqsave(&port->lock, flags);
487
488 tmp = LPC32XX_HSU_TX_TL8B | LPC32XX_HSU_RX_TL32B |
489 LPC32XX_HSU_OFFSET(20) | LPC32XX_HSU_TMO_INACT_4B;
490 writel(tmp, LPC32XX_HSUART_CTRL(port->membase));
491
492 lpc32xx_loopback_set(port->mapbase, 1); /* go to loopback mode */
493
494 spin_unlock_irqrestore(&port->lock, flags);
495
496 free_irq(port->irq, port);
497}
498
499/* port->lock is not held. */
500static void serial_lpc32xx_set_termios(struct uart_port *port,
501 struct ktermios *termios,
502 struct ktermios *old)
503{
504 unsigned long flags;
505 unsigned int baud, quot;
506 u32 tmp;
507
508 /* Always 8-bit, no parity, 1 stop bit */
509 termios->c_cflag &= ~(CSIZE | CSTOPB | PARENB | PARODD);
510 termios->c_cflag |= CS8;
511
512 termios->c_cflag &= ~(HUPCL | CMSPAR | CLOCAL | CRTSCTS);
513
514 baud = uart_get_baud_rate(port, termios, old, 0,
515 port->uartclk / 14);
516
517 quot = __serial_get_clock_div(port->uartclk, baud);
518
519 spin_lock_irqsave(&port->lock, flags);
520
521 /* Ignore characters? */
522 tmp = readl(LPC32XX_HSUART_CTRL(port->membase));
523 if ((termios->c_cflag & CREAD) == 0)
524 tmp &= ~(LPC32XX_HSU_RX_INT_EN | LPC32XX_HSU_ERR_INT_EN);
525 else
526 tmp |= LPC32XX_HSU_RX_INT_EN | LPC32XX_HSU_ERR_INT_EN;
527 writel(tmp, LPC32XX_HSUART_CTRL(port->membase));
528
529 writel(quot, LPC32XX_HSUART_RATE(port->membase));
530
531 uart_update_timeout(port, termios->c_cflag, baud);
532
533 spin_unlock_irqrestore(&port->lock, flags);
534
535 /* Don't rewrite B0 */
536 if (tty_termios_baud_rate(termios))
537 tty_termios_encode_baud_rate(termios, baud, baud);
538}
539
540static const char *serial_lpc32xx_type(struct uart_port *port)
541{
542 return MODNAME;
543}
544
545static void serial_lpc32xx_release_port(struct uart_port *port)
546{
547 if ((port->iotype == UPIO_MEM32) && (port->mapbase)) {
548 if (port->flags & UPF_IOREMAP) {
549 iounmap(port->membase);
550 port->membase = NULL;
551 }
552
553 release_mem_region(port->mapbase, SZ_4K);
554 }
555}
556
557static int serial_lpc32xx_request_port(struct uart_port *port)
558{
559 int ret = -ENODEV;
560
561 if ((port->iotype == UPIO_MEM32) && (port->mapbase)) {
562 ret = 0;
563
564 if (!request_mem_region(port->mapbase, SZ_4K, MODNAME))
565 ret = -EBUSY;
566 else if (port->flags & UPF_IOREMAP) {
567 port->membase = ioremap(port->mapbase, SZ_4K);
568 if (!port->membase) {
569 release_mem_region(port->mapbase, SZ_4K);
570 ret = -ENOMEM;
571 }
572 }
573 }
574
575 return ret;
576}
577
578static void serial_lpc32xx_config_port(struct uart_port *port, int uflags)
579{
580 int ret;
581
582 ret = serial_lpc32xx_request_port(port);
583 if (ret < 0)
584 return;
585 port->type = PORT_UART00;
586 port->fifosize = 64;
587
588 __serial_uart_flush(port);
589
590 writel((LPC32XX_HSU_TX_INT | LPC32XX_HSU_FE_INT |
591 LPC32XX_HSU_BRK_INT | LPC32XX_HSU_RX_OE_INT),
592 LPC32XX_HSUART_IIR(port->membase));
593
594 writel(0xFF, LPC32XX_HSUART_RATE(port->membase));
595
596 /* Set receiver timeout, HSU offset of 20, no break, no interrupts,
597 and default FIFO trigger levels */
598 writel(LPC32XX_HSU_TX_TL8B | LPC32XX_HSU_RX_TL32B |
599 LPC32XX_HSU_OFFSET(20) | LPC32XX_HSU_TMO_INACT_4B,
600 LPC32XX_HSUART_CTRL(port->membase));
601}
602
603static int serial_lpc32xx_verify_port(struct uart_port *port,
604 struct serial_struct *ser)
605{
606 int ret = 0;
607
608 if (ser->type != PORT_UART00)
609 ret = -EINVAL;
610
611 return ret;
612}
613
614static const struct uart_ops serial_lpc32xx_pops = {
615 .tx_empty = serial_lpc32xx_tx_empty,
616 .set_mctrl = serial_lpc32xx_set_mctrl,
617 .get_mctrl = serial_lpc32xx_get_mctrl,
618 .stop_tx = serial_lpc32xx_stop_tx,
619 .start_tx = serial_lpc32xx_start_tx,
620 .stop_rx = serial_lpc32xx_stop_rx,
621 .break_ctl = serial_lpc32xx_break_ctl,
622 .startup = serial_lpc32xx_startup,
623 .shutdown = serial_lpc32xx_shutdown,
624 .set_termios = serial_lpc32xx_set_termios,
625 .type = serial_lpc32xx_type,
626 .release_port = serial_lpc32xx_release_port,
627 .request_port = serial_lpc32xx_request_port,
628 .config_port = serial_lpc32xx_config_port,
629 .verify_port = serial_lpc32xx_verify_port,
630};
631
632/*
633 * Register a set of serial devices attached to a platform device
634 */
635static int serial_hs_lpc32xx_probe(struct platform_device *pdev)
636{
637 struct lpc32xx_hsuart_port *p = &lpc32xx_hs_ports[uarts_registered];
638 int ret = 0;
639 struct resource *res;
640
641 if (uarts_registered >= MAX_PORTS) {
642 dev_err(&pdev->dev,
643 "Error: Number of possible ports exceeded (%d)!\n",
644 uarts_registered + 1);
645 return -ENXIO;
646 }
647
648 memset(p, 0, sizeof(*p));
649
650 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
651 if (!res) {
652 dev_err(&pdev->dev,
653 "Error getting mem resource for HS UART port %d\n",
654 uarts_registered);
655 return -ENXIO;
656 }
657 p->port.mapbase = res->start;
658 p->port.membase = NULL;
659
660 ret = platform_get_irq(pdev, 0);
661 if (ret < 0)
662 return ret;
663 p->port.irq = ret;
664
665 p->port.iotype = UPIO_MEM32;
666 p->port.uartclk = LPC32XX_MAIN_OSC_FREQ;
667 p->port.regshift = 2;
668 p->port.flags = UPF_BOOT_AUTOCONF | UPF_FIXED_PORT | UPF_IOREMAP;
669 p->port.dev = &pdev->dev;
670 p->port.ops = &serial_lpc32xx_pops;
671 p->port.line = uarts_registered++;
672 spin_lock_init(&p->port.lock);
673
674 /* send port to loopback mode by default */
675 lpc32xx_loopback_set(p->port.mapbase, 1);
676
677 ret = uart_add_one_port(&lpc32xx_hs_reg, &p->port);
678
679 platform_set_drvdata(pdev, p);
680
681 return ret;
682}
683
684/*
685 * Remove serial ports registered against a platform device.
686 */
687static int serial_hs_lpc32xx_remove(struct platform_device *pdev)
688{
689 struct lpc32xx_hsuart_port *p = platform_get_drvdata(pdev);
690
691 uart_remove_one_port(&lpc32xx_hs_reg, &p->port);
692
693 return 0;
694}
695
696
697#ifdef CONFIG_PM
698static int serial_hs_lpc32xx_suspend(struct platform_device *pdev,
699 pm_message_t state)
700{
701 struct lpc32xx_hsuart_port *p = platform_get_drvdata(pdev);
702
703 uart_suspend_port(&lpc32xx_hs_reg, &p->port);
704
705 return 0;
706}
707
708static int serial_hs_lpc32xx_resume(struct platform_device *pdev)
709{
710 struct lpc32xx_hsuart_port *p = platform_get_drvdata(pdev);
711
712 uart_resume_port(&lpc32xx_hs_reg, &p->port);
713
714 return 0;
715}
716#else
717#define serial_hs_lpc32xx_suspend NULL
718#define serial_hs_lpc32xx_resume NULL
719#endif
720
721static const struct of_device_id serial_hs_lpc32xx_dt_ids[] = {
722 { .compatible = "nxp,lpc3220-hsuart" },
723 { /* sentinel */ }
724};
725
726MODULE_DEVICE_TABLE(of, serial_hs_lpc32xx_dt_ids);
727
728static struct platform_driver serial_hs_lpc32xx_driver = {
729 .probe = serial_hs_lpc32xx_probe,
730 .remove = serial_hs_lpc32xx_remove,
731 .suspend = serial_hs_lpc32xx_suspend,
732 .resume = serial_hs_lpc32xx_resume,
733 .driver = {
734 .name = MODNAME,
735 .of_match_table = serial_hs_lpc32xx_dt_ids,
736 },
737};
738
739static int __init lpc32xx_hsuart_init(void)
740{
741 int ret;
742
743 ret = uart_register_driver(&lpc32xx_hs_reg);
744 if (ret)
745 return ret;
746
747 ret = platform_driver_register(&serial_hs_lpc32xx_driver);
748 if (ret)
749 uart_unregister_driver(&lpc32xx_hs_reg);
750
751 return ret;
752}
753
754static void __exit lpc32xx_hsuart_exit(void)
755{
756 platform_driver_unregister(&serial_hs_lpc32xx_driver);
757 uart_unregister_driver(&lpc32xx_hs_reg);
758}
759
760module_init(lpc32xx_hsuart_init);
761module_exit(lpc32xx_hsuart_exit);
762
763MODULE_AUTHOR("Kevin Wells <kevin.wells@nxp.com>");
764MODULE_AUTHOR("Roland Stigge <stigge@antcom.de>");
765MODULE_DESCRIPTION("NXP LPC32XX High Speed UART driver");
766MODULE_LICENSE("GPL");
1/*
2 * High Speed Serial Ports on NXP LPC32xx SoC
3 *
4 * Authors: Kevin Wells <kevin.wells@nxp.com>
5 * Roland Stigge <stigge@antcom.de>
6 *
7 * Copyright (C) 2010 NXP Semiconductors
8 * Copyright (C) 2012 Roland Stigge
9 *
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License as published by
12 * the Free Software Foundation; either version 2 of the License, or
13 * (at your option) any later version.
14 *
15 * This program is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 * GNU General Public License for more details.
19 */
20
21#include <linux/module.h>
22#include <linux/ioport.h>
23#include <linux/init.h>
24#include <linux/console.h>
25#include <linux/sysrq.h>
26#include <linux/tty.h>
27#include <linux/tty_flip.h>
28#include <linux/serial_core.h>
29#include <linux/serial.h>
30#include <linux/platform_device.h>
31#include <linux/delay.h>
32#include <linux/nmi.h>
33#include <linux/io.h>
34#include <linux/irq.h>
35#include <linux/gpio.h>
36#include <linux/of.h>
37#include <mach/platform.h>
38#include <mach/hardware.h>
39
40/*
41 * High Speed UART register offsets
42 */
43#define LPC32XX_HSUART_FIFO(x) ((x) + 0x00)
44#define LPC32XX_HSUART_LEVEL(x) ((x) + 0x04)
45#define LPC32XX_HSUART_IIR(x) ((x) + 0x08)
46#define LPC32XX_HSUART_CTRL(x) ((x) + 0x0C)
47#define LPC32XX_HSUART_RATE(x) ((x) + 0x10)
48
49#define LPC32XX_HSU_BREAK_DATA (1 << 10)
50#define LPC32XX_HSU_ERROR_DATA (1 << 9)
51#define LPC32XX_HSU_RX_EMPTY (1 << 8)
52
53#define LPC32XX_HSU_TX_LEV(n) (((n) >> 8) & 0xFF)
54#define LPC32XX_HSU_RX_LEV(n) ((n) & 0xFF)
55
56#define LPC32XX_HSU_TX_INT_SET (1 << 6)
57#define LPC32XX_HSU_RX_OE_INT (1 << 5)
58#define LPC32XX_HSU_BRK_INT (1 << 4)
59#define LPC32XX_HSU_FE_INT (1 << 3)
60#define LPC32XX_HSU_RX_TIMEOUT_INT (1 << 2)
61#define LPC32XX_HSU_RX_TRIG_INT (1 << 1)
62#define LPC32XX_HSU_TX_INT (1 << 0)
63
64#define LPC32XX_HSU_HRTS_INV (1 << 21)
65#define LPC32XX_HSU_HRTS_TRIG_8B (0x0 << 19)
66#define LPC32XX_HSU_HRTS_TRIG_16B (0x1 << 19)
67#define LPC32XX_HSU_HRTS_TRIG_32B (0x2 << 19)
68#define LPC32XX_HSU_HRTS_TRIG_48B (0x3 << 19)
69#define LPC32XX_HSU_HRTS_EN (1 << 18)
70#define LPC32XX_HSU_TMO_DISABLED (0x0 << 16)
71#define LPC32XX_HSU_TMO_INACT_4B (0x1 << 16)
72#define LPC32XX_HSU_TMO_INACT_8B (0x2 << 16)
73#define LPC32XX_HSU_TMO_INACT_16B (0x3 << 16)
74#define LPC32XX_HSU_HCTS_INV (1 << 15)
75#define LPC32XX_HSU_HCTS_EN (1 << 14)
76#define LPC32XX_HSU_OFFSET(n) ((n) << 9)
77#define LPC32XX_HSU_BREAK (1 << 8)
78#define LPC32XX_HSU_ERR_INT_EN (1 << 7)
79#define LPC32XX_HSU_RX_INT_EN (1 << 6)
80#define LPC32XX_HSU_TX_INT_EN (1 << 5)
81#define LPC32XX_HSU_RX_TL1B (0x0 << 2)
82#define LPC32XX_HSU_RX_TL4B (0x1 << 2)
83#define LPC32XX_HSU_RX_TL8B (0x2 << 2)
84#define LPC32XX_HSU_RX_TL16B (0x3 << 2)
85#define LPC32XX_HSU_RX_TL32B (0x4 << 2)
86#define LPC32XX_HSU_RX_TL48B (0x5 << 2)
87#define LPC32XX_HSU_TX_TLEMPTY (0x0 << 0)
88#define LPC32XX_HSU_TX_TL0B (0x0 << 0)
89#define LPC32XX_HSU_TX_TL4B (0x1 << 0)
90#define LPC32XX_HSU_TX_TL8B (0x2 << 0)
91#define LPC32XX_HSU_TX_TL16B (0x3 << 0)
92
93#define MODNAME "lpc32xx_hsuart"
94
95struct lpc32xx_hsuart_port {
96 struct uart_port port;
97};
98
99#define FIFO_READ_LIMIT 128
100#define MAX_PORTS 3
101#define LPC32XX_TTY_NAME "ttyTX"
102static struct lpc32xx_hsuart_port lpc32xx_hs_ports[MAX_PORTS];
103
104#ifdef CONFIG_SERIAL_HS_LPC32XX_CONSOLE
105static void wait_for_xmit_empty(struct uart_port *port)
106{
107 unsigned int timeout = 10000;
108
109 do {
110 if (LPC32XX_HSU_TX_LEV(readl(LPC32XX_HSUART_LEVEL(
111 port->membase))) == 0)
112 break;
113 if (--timeout == 0)
114 break;
115 udelay(1);
116 } while (1);
117}
118
119static void wait_for_xmit_ready(struct uart_port *port)
120{
121 unsigned int timeout = 10000;
122
123 while (1) {
124 if (LPC32XX_HSU_TX_LEV(readl(LPC32XX_HSUART_LEVEL(
125 port->membase))) < 32)
126 break;
127 if (--timeout == 0)
128 break;
129 udelay(1);
130 }
131}
132
133static void lpc32xx_hsuart_console_putchar(struct uart_port *port, int ch)
134{
135 wait_for_xmit_ready(port);
136 writel((u32)ch, LPC32XX_HSUART_FIFO(port->membase));
137}
138
139static void lpc32xx_hsuart_console_write(struct console *co, const char *s,
140 unsigned int count)
141{
142 struct lpc32xx_hsuart_port *up = &lpc32xx_hs_ports[co->index];
143 unsigned long flags;
144 int locked = 1;
145
146 touch_nmi_watchdog();
147 local_irq_save(flags);
148 if (up->port.sysrq)
149 locked = 0;
150 else if (oops_in_progress)
151 locked = spin_trylock(&up->port.lock);
152 else
153 spin_lock(&up->port.lock);
154
155 uart_console_write(&up->port, s, count, lpc32xx_hsuart_console_putchar);
156 wait_for_xmit_empty(&up->port);
157
158 if (locked)
159 spin_unlock(&up->port.lock);
160 local_irq_restore(flags);
161}
162
163static int __init lpc32xx_hsuart_console_setup(struct console *co,
164 char *options)
165{
166 struct uart_port *port;
167 int baud = 115200;
168 int bits = 8;
169 int parity = 'n';
170 int flow = 'n';
171
172 if (co->index >= MAX_PORTS)
173 co->index = 0;
174
175 port = &lpc32xx_hs_ports[co->index].port;
176 if (!port->membase)
177 return -ENODEV;
178
179 if (options)
180 uart_parse_options(options, &baud, &parity, &bits, &flow);
181
182 return uart_set_options(port, co, baud, parity, bits, flow);
183}
184
185static struct uart_driver lpc32xx_hsuart_reg;
186static struct console lpc32xx_hsuart_console = {
187 .name = LPC32XX_TTY_NAME,
188 .write = lpc32xx_hsuart_console_write,
189 .device = uart_console_device,
190 .setup = lpc32xx_hsuart_console_setup,
191 .flags = CON_PRINTBUFFER,
192 .index = -1,
193 .data = &lpc32xx_hsuart_reg,
194};
195
196static int __init lpc32xx_hsuart_console_init(void)
197{
198 register_console(&lpc32xx_hsuart_console);
199 return 0;
200}
201console_initcall(lpc32xx_hsuart_console_init);
202
203#define LPC32XX_HSUART_CONSOLE (&lpc32xx_hsuart_console)
204#else
205#define LPC32XX_HSUART_CONSOLE NULL
206#endif
207
208static struct uart_driver lpc32xx_hs_reg = {
209 .owner = THIS_MODULE,
210 .driver_name = MODNAME,
211 .dev_name = LPC32XX_TTY_NAME,
212 .nr = MAX_PORTS,
213 .cons = LPC32XX_HSUART_CONSOLE,
214};
215static int uarts_registered;
216
217static unsigned int __serial_get_clock_div(unsigned long uartclk,
218 unsigned long rate)
219{
220 u32 div, goodrate, hsu_rate, l_hsu_rate, comprate;
221 u32 rate_diff;
222
223 /* Find the closest divider to get the desired clock rate */
224 div = uartclk / rate;
225 goodrate = hsu_rate = (div / 14) - 1;
226 if (hsu_rate != 0)
227 hsu_rate--;
228
229 /* Tweak divider */
230 l_hsu_rate = hsu_rate + 3;
231 rate_diff = 0xFFFFFFFF;
232
233 while (hsu_rate < l_hsu_rate) {
234 comprate = uartclk / ((hsu_rate + 1) * 14);
235 if (abs(comprate - rate) < rate_diff) {
236 goodrate = hsu_rate;
237 rate_diff = abs(comprate - rate);
238 }
239
240 hsu_rate++;
241 }
242 if (hsu_rate > 0xFF)
243 hsu_rate = 0xFF;
244
245 return goodrate;
246}
247
248static void __serial_uart_flush(struct uart_port *port)
249{
250 u32 tmp;
251 int cnt = 0;
252
253 while ((readl(LPC32XX_HSUART_LEVEL(port->membase)) > 0) &&
254 (cnt++ < FIFO_READ_LIMIT))
255 tmp = readl(LPC32XX_HSUART_FIFO(port->membase));
256}
257
258static void __serial_lpc32xx_rx(struct uart_port *port)
259{
260 struct tty_port *tport = &port->state->port;
261 unsigned int tmp, flag;
262
263 /* Read data from FIFO and push into terminal */
264 tmp = readl(LPC32XX_HSUART_FIFO(port->membase));
265 while (!(tmp & LPC32XX_HSU_RX_EMPTY)) {
266 flag = TTY_NORMAL;
267 port->icount.rx++;
268
269 if (tmp & LPC32XX_HSU_ERROR_DATA) {
270 /* Framing error */
271 writel(LPC32XX_HSU_FE_INT,
272 LPC32XX_HSUART_IIR(port->membase));
273 port->icount.frame++;
274 flag = TTY_FRAME;
275 tty_insert_flip_char(tport, 0, TTY_FRAME);
276 }
277
278 tty_insert_flip_char(tport, (tmp & 0xFF), flag);
279
280 tmp = readl(LPC32XX_HSUART_FIFO(port->membase));
281 }
282
283 spin_unlock(&port->lock);
284 tty_flip_buffer_push(tport);
285 spin_lock(&port->lock);
286}
287
288static void __serial_lpc32xx_tx(struct uart_port *port)
289{
290 struct circ_buf *xmit = &port->state->xmit;
291 unsigned int tmp;
292
293 if (port->x_char) {
294 writel((u32)port->x_char, LPC32XX_HSUART_FIFO(port->membase));
295 port->icount.tx++;
296 port->x_char = 0;
297 return;
298 }
299
300 if (uart_circ_empty(xmit) || uart_tx_stopped(port))
301 goto exit_tx;
302
303 /* Transfer data */
304 while (LPC32XX_HSU_TX_LEV(readl(
305 LPC32XX_HSUART_LEVEL(port->membase))) < 64) {
306 writel((u32) xmit->buf[xmit->tail],
307 LPC32XX_HSUART_FIFO(port->membase));
308 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
309 port->icount.tx++;
310 if (uart_circ_empty(xmit))
311 break;
312 }
313
314 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
315 uart_write_wakeup(port);
316
317exit_tx:
318 if (uart_circ_empty(xmit)) {
319 tmp = readl(LPC32XX_HSUART_CTRL(port->membase));
320 tmp &= ~LPC32XX_HSU_TX_INT_EN;
321 writel(tmp, LPC32XX_HSUART_CTRL(port->membase));
322 }
323}
324
325static irqreturn_t serial_lpc32xx_interrupt(int irq, void *dev_id)
326{
327 struct uart_port *port = dev_id;
328 struct tty_port *tport = &port->state->port;
329 u32 status;
330
331 spin_lock(&port->lock);
332
333 /* Read UART status and clear latched interrupts */
334 status = readl(LPC32XX_HSUART_IIR(port->membase));
335
336 if (status & LPC32XX_HSU_BRK_INT) {
337 /* Break received */
338 writel(LPC32XX_HSU_BRK_INT, LPC32XX_HSUART_IIR(port->membase));
339 port->icount.brk++;
340 uart_handle_break(port);
341 }
342
343 /* Framing error */
344 if (status & LPC32XX_HSU_FE_INT)
345 writel(LPC32XX_HSU_FE_INT, LPC32XX_HSUART_IIR(port->membase));
346
347 if (status & LPC32XX_HSU_RX_OE_INT) {
348 /* Receive FIFO overrun */
349 writel(LPC32XX_HSU_RX_OE_INT,
350 LPC32XX_HSUART_IIR(port->membase));
351 port->icount.overrun++;
352 tty_insert_flip_char(tport, 0, TTY_OVERRUN);
353 tty_schedule_flip(tport);
354 }
355
356 /* Data received? */
357 if (status & (LPC32XX_HSU_RX_TIMEOUT_INT | LPC32XX_HSU_RX_TRIG_INT))
358 __serial_lpc32xx_rx(port);
359
360 /* Transmit data request? */
361 if ((status & LPC32XX_HSU_TX_INT) && (!uart_tx_stopped(port))) {
362 writel(LPC32XX_HSU_TX_INT, LPC32XX_HSUART_IIR(port->membase));
363 __serial_lpc32xx_tx(port);
364 }
365
366 spin_unlock(&port->lock);
367
368 return IRQ_HANDLED;
369}
370
371/* port->lock is not held. */
372static unsigned int serial_lpc32xx_tx_empty(struct uart_port *port)
373{
374 unsigned int ret = 0;
375
376 if (LPC32XX_HSU_TX_LEV(readl(LPC32XX_HSUART_LEVEL(port->membase))) == 0)
377 ret = TIOCSER_TEMT;
378
379 return ret;
380}
381
382/* port->lock held by caller. */
383static void serial_lpc32xx_set_mctrl(struct uart_port *port,
384 unsigned int mctrl)
385{
386 /* No signals are supported on HS UARTs */
387}
388
389/* port->lock is held by caller and interrupts are disabled. */
390static unsigned int serial_lpc32xx_get_mctrl(struct uart_port *port)
391{
392 /* No signals are supported on HS UARTs */
393 return TIOCM_CAR | TIOCM_DSR | TIOCM_CTS;
394}
395
396/* port->lock held by caller. */
397static void serial_lpc32xx_stop_tx(struct uart_port *port)
398{
399 u32 tmp;
400
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. */
407static void serial_lpc32xx_start_tx(struct uart_port *port)
408{
409 u32 tmp;
410
411 __serial_lpc32xx_tx(port);
412 tmp = readl(LPC32XX_HSUART_CTRL(port->membase));
413 tmp |= LPC32XX_HSU_TX_INT_EN;
414 writel(tmp, LPC32XX_HSUART_CTRL(port->membase));
415}
416
417/* port->lock held by caller. */
418static void serial_lpc32xx_stop_rx(struct uart_port *port)
419{
420 u32 tmp;
421
422 tmp = readl(LPC32XX_HSUART_CTRL(port->membase));
423 tmp &= ~(LPC32XX_HSU_RX_INT_EN | LPC32XX_HSU_ERR_INT_EN);
424 writel(tmp, LPC32XX_HSUART_CTRL(port->membase));
425
426 writel((LPC32XX_HSU_BRK_INT | LPC32XX_HSU_RX_OE_INT |
427 LPC32XX_HSU_FE_INT), LPC32XX_HSUART_IIR(port->membase));
428}
429
430/* port->lock is not held. */
431static void serial_lpc32xx_break_ctl(struct uart_port *port,
432 int break_state)
433{
434 unsigned long flags;
435 u32 tmp;
436
437 spin_lock_irqsave(&port->lock, flags);
438 tmp = readl(LPC32XX_HSUART_CTRL(port->membase));
439 if (break_state != 0)
440 tmp |= LPC32XX_HSU_BREAK;
441 else
442 tmp &= ~LPC32XX_HSU_BREAK;
443 writel(tmp, LPC32XX_HSUART_CTRL(port->membase));
444 spin_unlock_irqrestore(&port->lock, flags);
445}
446
447/* LPC3250 Errata HSUART.1: Hang workaround via loopback mode on inactivity */
448static void lpc32xx_loopback_set(resource_size_t mapbase, int state)
449{
450 int bit;
451 u32 tmp;
452
453 switch (mapbase) {
454 case LPC32XX_HS_UART1_BASE:
455 bit = 0;
456 break;
457 case LPC32XX_HS_UART2_BASE:
458 bit = 1;
459 break;
460 case LPC32XX_HS_UART7_BASE:
461 bit = 6;
462 break;
463 default:
464 WARN(1, "lpc32xx_hs: Warning: Unknown port at %08x\n", mapbase);
465 return;
466 }
467
468 tmp = readl(LPC32XX_UARTCTL_CLOOP);
469 if (state)
470 tmp |= (1 << bit);
471 else
472 tmp &= ~(1 << bit);
473 writel(tmp, LPC32XX_UARTCTL_CLOOP);
474}
475
476/* port->lock is not held. */
477static int serial_lpc32xx_startup(struct uart_port *port)
478{
479 int retval;
480 unsigned long flags;
481 u32 tmp;
482
483 spin_lock_irqsave(&port->lock, flags);
484
485 __serial_uart_flush(port);
486
487 writel((LPC32XX_HSU_TX_INT | LPC32XX_HSU_FE_INT |
488 LPC32XX_HSU_BRK_INT | LPC32XX_HSU_RX_OE_INT),
489 LPC32XX_HSUART_IIR(port->membase));
490
491 writel(0xFF, LPC32XX_HSUART_RATE(port->membase));
492
493 /*
494 * Set receiver timeout, HSU offset of 20, no break, no interrupts,
495 * and default FIFO trigger levels
496 */
497 tmp = LPC32XX_HSU_TX_TL8B | LPC32XX_HSU_RX_TL32B |
498 LPC32XX_HSU_OFFSET(20) | LPC32XX_HSU_TMO_INACT_4B;
499 writel(tmp, LPC32XX_HSUART_CTRL(port->membase));
500
501 lpc32xx_loopback_set(port->mapbase, 0); /* get out of loopback mode */
502
503 spin_unlock_irqrestore(&port->lock, flags);
504
505 retval = request_irq(port->irq, serial_lpc32xx_interrupt,
506 0, MODNAME, port);
507 if (!retval)
508 writel((tmp | LPC32XX_HSU_RX_INT_EN | LPC32XX_HSU_ERR_INT_EN),
509 LPC32XX_HSUART_CTRL(port->membase));
510
511 return retval;
512}
513
514/* port->lock is not held. */
515static void serial_lpc32xx_shutdown(struct uart_port *port)
516{
517 u32 tmp;
518 unsigned long flags;
519
520 spin_lock_irqsave(&port->lock, flags);
521
522 tmp = LPC32XX_HSU_TX_TL8B | LPC32XX_HSU_RX_TL32B |
523 LPC32XX_HSU_OFFSET(20) | LPC32XX_HSU_TMO_INACT_4B;
524 writel(tmp, LPC32XX_HSUART_CTRL(port->membase));
525
526 lpc32xx_loopback_set(port->mapbase, 1); /* go to loopback mode */
527
528 spin_unlock_irqrestore(&port->lock, flags);
529
530 free_irq(port->irq, port);
531}
532
533/* port->lock is not held. */
534static void serial_lpc32xx_set_termios(struct uart_port *port,
535 struct ktermios *termios,
536 struct ktermios *old)
537{
538 unsigned long flags;
539 unsigned int baud, quot;
540 u32 tmp;
541
542 /* Always 8-bit, no parity, 1 stop bit */
543 termios->c_cflag &= ~(CSIZE | CSTOPB | PARENB | PARODD);
544 termios->c_cflag |= CS8;
545
546 termios->c_cflag &= ~(HUPCL | CMSPAR | CLOCAL | CRTSCTS);
547
548 baud = uart_get_baud_rate(port, termios, old, 0,
549 port->uartclk / 14);
550
551 quot = __serial_get_clock_div(port->uartclk, baud);
552
553 spin_lock_irqsave(&port->lock, flags);
554
555 /* Ignore characters? */
556 tmp = readl(LPC32XX_HSUART_CTRL(port->membase));
557 if ((termios->c_cflag & CREAD) == 0)
558 tmp &= ~(LPC32XX_HSU_RX_INT_EN | LPC32XX_HSU_ERR_INT_EN);
559 else
560 tmp |= LPC32XX_HSU_RX_INT_EN | LPC32XX_HSU_ERR_INT_EN;
561 writel(tmp, LPC32XX_HSUART_CTRL(port->membase));
562
563 writel(quot, LPC32XX_HSUART_RATE(port->membase));
564
565 uart_update_timeout(port, termios->c_cflag, baud);
566
567 spin_unlock_irqrestore(&port->lock, flags);
568
569 /* Don't rewrite B0 */
570 if (tty_termios_baud_rate(termios))
571 tty_termios_encode_baud_rate(termios, baud, baud);
572}
573
574static const char *serial_lpc32xx_type(struct uart_port *port)
575{
576 return MODNAME;
577}
578
579static void serial_lpc32xx_release_port(struct uart_port *port)
580{
581 if ((port->iotype == UPIO_MEM32) && (port->mapbase)) {
582 if (port->flags & UPF_IOREMAP) {
583 iounmap(port->membase);
584 port->membase = NULL;
585 }
586
587 release_mem_region(port->mapbase, SZ_4K);
588 }
589}
590
591static int serial_lpc32xx_request_port(struct uart_port *port)
592{
593 int ret = -ENODEV;
594
595 if ((port->iotype == UPIO_MEM32) && (port->mapbase)) {
596 ret = 0;
597
598 if (!request_mem_region(port->mapbase, SZ_4K, MODNAME))
599 ret = -EBUSY;
600 else if (port->flags & UPF_IOREMAP) {
601 port->membase = ioremap(port->mapbase, SZ_4K);
602 if (!port->membase) {
603 release_mem_region(port->mapbase, SZ_4K);
604 ret = -ENOMEM;
605 }
606 }
607 }
608
609 return ret;
610}
611
612static void serial_lpc32xx_config_port(struct uart_port *port, int uflags)
613{
614 int ret;
615
616 ret = serial_lpc32xx_request_port(port);
617 if (ret < 0)
618 return;
619 port->type = PORT_UART00;
620 port->fifosize = 64;
621
622 __serial_uart_flush(port);
623
624 writel((LPC32XX_HSU_TX_INT | LPC32XX_HSU_FE_INT |
625 LPC32XX_HSU_BRK_INT | LPC32XX_HSU_RX_OE_INT),
626 LPC32XX_HSUART_IIR(port->membase));
627
628 writel(0xFF, LPC32XX_HSUART_RATE(port->membase));
629
630 /* Set receiver timeout, HSU offset of 20, no break, no interrupts,
631 and default FIFO trigger levels */
632 writel(LPC32XX_HSU_TX_TL8B | LPC32XX_HSU_RX_TL32B |
633 LPC32XX_HSU_OFFSET(20) | LPC32XX_HSU_TMO_INACT_4B,
634 LPC32XX_HSUART_CTRL(port->membase));
635}
636
637static int serial_lpc32xx_verify_port(struct uart_port *port,
638 struct serial_struct *ser)
639{
640 int ret = 0;
641
642 if (ser->type != PORT_UART00)
643 ret = -EINVAL;
644
645 return ret;
646}
647
648static struct uart_ops serial_lpc32xx_pops = {
649 .tx_empty = serial_lpc32xx_tx_empty,
650 .set_mctrl = serial_lpc32xx_set_mctrl,
651 .get_mctrl = serial_lpc32xx_get_mctrl,
652 .stop_tx = serial_lpc32xx_stop_tx,
653 .start_tx = serial_lpc32xx_start_tx,
654 .stop_rx = serial_lpc32xx_stop_rx,
655 .break_ctl = serial_lpc32xx_break_ctl,
656 .startup = serial_lpc32xx_startup,
657 .shutdown = serial_lpc32xx_shutdown,
658 .set_termios = serial_lpc32xx_set_termios,
659 .type = serial_lpc32xx_type,
660 .release_port = serial_lpc32xx_release_port,
661 .request_port = serial_lpc32xx_request_port,
662 .config_port = serial_lpc32xx_config_port,
663 .verify_port = serial_lpc32xx_verify_port,
664};
665
666/*
667 * Register a set of serial devices attached to a platform device
668 */
669static int serial_hs_lpc32xx_probe(struct platform_device *pdev)
670{
671 struct lpc32xx_hsuart_port *p = &lpc32xx_hs_ports[uarts_registered];
672 int ret = 0;
673 struct resource *res;
674
675 if (uarts_registered >= MAX_PORTS) {
676 dev_err(&pdev->dev,
677 "Error: Number of possible ports exceeded (%d)!\n",
678 uarts_registered + 1);
679 return -ENXIO;
680 }
681
682 memset(p, 0, sizeof(*p));
683
684 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
685 if (!res) {
686 dev_err(&pdev->dev,
687 "Error getting mem resource for HS UART port %d\n",
688 uarts_registered);
689 return -ENXIO;
690 }
691 p->port.mapbase = res->start;
692 p->port.membase = NULL;
693
694 ret = platform_get_irq(pdev, 0);
695 if (ret < 0) {
696 dev_err(&pdev->dev, "Error getting irq for HS UART port %d\n",
697 uarts_registered);
698 return ret;
699 }
700 p->port.irq = ret;
701
702 p->port.iotype = UPIO_MEM32;
703 p->port.uartclk = LPC32XX_MAIN_OSC_FREQ;
704 p->port.regshift = 2;
705 p->port.flags = UPF_BOOT_AUTOCONF | UPF_FIXED_PORT | UPF_IOREMAP;
706 p->port.dev = &pdev->dev;
707 p->port.ops = &serial_lpc32xx_pops;
708 p->port.line = uarts_registered++;
709 spin_lock_init(&p->port.lock);
710
711 /* send port to loopback mode by default */
712 lpc32xx_loopback_set(p->port.mapbase, 1);
713
714 ret = uart_add_one_port(&lpc32xx_hs_reg, &p->port);
715
716 platform_set_drvdata(pdev, p);
717
718 return ret;
719}
720
721/*
722 * Remove serial ports registered against a platform device.
723 */
724static int serial_hs_lpc32xx_remove(struct platform_device *pdev)
725{
726 struct lpc32xx_hsuart_port *p = platform_get_drvdata(pdev);
727
728 uart_remove_one_port(&lpc32xx_hs_reg, &p->port);
729
730 return 0;
731}
732
733
734#ifdef CONFIG_PM
735static int serial_hs_lpc32xx_suspend(struct platform_device *pdev,
736 pm_message_t state)
737{
738 struct lpc32xx_hsuart_port *p = platform_get_drvdata(pdev);
739
740 uart_suspend_port(&lpc32xx_hs_reg, &p->port);
741
742 return 0;
743}
744
745static int serial_hs_lpc32xx_resume(struct platform_device *pdev)
746{
747 struct lpc32xx_hsuart_port *p = platform_get_drvdata(pdev);
748
749 uart_resume_port(&lpc32xx_hs_reg, &p->port);
750
751 return 0;
752}
753#else
754#define serial_hs_lpc32xx_suspend NULL
755#define serial_hs_lpc32xx_resume NULL
756#endif
757
758static const struct of_device_id serial_hs_lpc32xx_dt_ids[] = {
759 { .compatible = "nxp,lpc3220-hsuart" },
760 { /* sentinel */ }
761};
762
763MODULE_DEVICE_TABLE(of, serial_hs_lpc32xx_dt_ids);
764
765static struct platform_driver serial_hs_lpc32xx_driver = {
766 .probe = serial_hs_lpc32xx_probe,
767 .remove = serial_hs_lpc32xx_remove,
768 .suspend = serial_hs_lpc32xx_suspend,
769 .resume = serial_hs_lpc32xx_resume,
770 .driver = {
771 .name = MODNAME,
772 .of_match_table = serial_hs_lpc32xx_dt_ids,
773 },
774};
775
776static int __init lpc32xx_hsuart_init(void)
777{
778 int ret;
779
780 ret = uart_register_driver(&lpc32xx_hs_reg);
781 if (ret)
782 return ret;
783
784 ret = platform_driver_register(&serial_hs_lpc32xx_driver);
785 if (ret)
786 uart_unregister_driver(&lpc32xx_hs_reg);
787
788 return ret;
789}
790
791static void __exit lpc32xx_hsuart_exit(void)
792{
793 platform_driver_unregister(&serial_hs_lpc32xx_driver);
794 uart_unregister_driver(&lpc32xx_hs_reg);
795}
796
797module_init(lpc32xx_hsuart_init);
798module_exit(lpc32xx_hsuart_exit);
799
800MODULE_AUTHOR("Kevin Wells <kevin.wells@nxp.com>");
801MODULE_AUTHOR("Roland Stigge <stigge@antcom.de>");
802MODULE_DESCRIPTION("NXP LPC32XX High Speed UART driver");
803MODULE_LICENSE("GPL");