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1 /*
2 * Based on drivers/char/serial.c, by Linus Torvalds, Theodore Ts'o.
3 *
4 * This program is free software; you can redistribute it and/or modify it
5 * under the terms of the GNU General Public License version 2 as published
6 * by the Free Software Foundation.
7 *
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
11 * GNU General Public License for more details.
12 *
13 * You should have received a copy of the GNU General Public License
14 * along with this program; if not, write to the Free Software
15 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
16 *
17 * Copyright (C) 2004 Infineon IFAP DC COM CPE
18 * Copyright (C) 2007 Felix Fietkau <nbd@openwrt.org>
19 * Copyright (C) 2007 John Crispin <blogic@openwrt.org>
20 * Copyright (C) 2010 Thomas Langer, <thomas.langer@lantiq.com>
21 */
22
23 #include <linux/slab.h>
24 #include <linux/ioport.h>
25 #include <linux/init.h>
26 #include <linux/console.h>
27 #include <linux/sysrq.h>
28 #include <linux/device.h>
29 #include <linux/tty.h>
30 #include <linux/tty_flip.h>
31 #include <linux/serial_core.h>
32 #include <linux/serial.h>
33 #include <linux/of_platform.h>
34 #include <linux/of_address.h>
35 #include <linux/of_irq.h>
36 #include <linux/io.h>
37 #include <linux/clk.h>
38 #include <linux/gpio.h>
39
40 #include <lantiq_soc.h>
41
42 #define PORT_LTQ_ASC 111
43 #define MAXPORTS 2
44 #define UART_DUMMY_UER_RX 1
45 #define DRVNAME "lantiq,asc"
46 #ifdef __BIG_ENDIAN
47 #define LTQ_ASC_TBUF (0x0020 + 3)
48 #define LTQ_ASC_RBUF (0x0024 + 3)
49 #else
50 #define LTQ_ASC_TBUF 0x0020
51 #define LTQ_ASC_RBUF 0x0024
52 #endif
53 #define LTQ_ASC_FSTAT 0x0048
54 #define LTQ_ASC_WHBSTATE 0x0018
55 #define LTQ_ASC_STATE 0x0014
56 #define LTQ_ASC_IRNCR 0x00F8
57 #define LTQ_ASC_CLC 0x0000
58 #define LTQ_ASC_ID 0x0008
59 #define LTQ_ASC_PISEL 0x0004
60 #define LTQ_ASC_TXFCON 0x0044
61 #define LTQ_ASC_RXFCON 0x0040
62 #define LTQ_ASC_CON 0x0010
63 #define LTQ_ASC_BG 0x0050
64 #define LTQ_ASC_IRNREN 0x00F4
65
66 #define ASC_IRNREN_TX 0x1
67 #define ASC_IRNREN_RX 0x2
68 #define ASC_IRNREN_ERR 0x4
69 #define ASC_IRNREN_TX_BUF 0x8
70 #define ASC_IRNCR_TIR 0x1
71 #define ASC_IRNCR_RIR 0x2
72 #define ASC_IRNCR_EIR 0x4
73
74 #define ASCOPT_CSIZE 0x3
75 #define TXFIFO_FL 1
76 #define RXFIFO_FL 1
77 #define ASCCLC_DISS 0x2
78 #define ASCCLC_RMCMASK 0x0000FF00
79 #define ASCCLC_RMCOFFSET 8
80 #define ASCCON_M_8ASYNC 0x0
81 #define ASCCON_M_7ASYNC 0x2
82 #define ASCCON_ODD 0x00000020
83 #define ASCCON_STP 0x00000080
84 #define ASCCON_BRS 0x00000100
85 #define ASCCON_FDE 0x00000200
86 #define ASCCON_R 0x00008000
87 #define ASCCON_FEN 0x00020000
88 #define ASCCON_ROEN 0x00080000
89 #define ASCCON_TOEN 0x00100000
90 #define ASCSTATE_PE 0x00010000
91 #define ASCSTATE_FE 0x00020000
92 #define ASCSTATE_ROE 0x00080000
93 #define ASCSTATE_ANY (ASCSTATE_ROE|ASCSTATE_PE|ASCSTATE_FE)
94 #define ASCWHBSTATE_CLRREN 0x00000001
95 #define ASCWHBSTATE_SETREN 0x00000002
96 #define ASCWHBSTATE_CLRPE 0x00000004
97 #define ASCWHBSTATE_CLRFE 0x00000008
98 #define ASCWHBSTATE_CLRROE 0x00000020
99 #define ASCTXFCON_TXFEN 0x0001
100 #define ASCTXFCON_TXFFLU 0x0002
101 #define ASCTXFCON_TXFITLMASK 0x3F00
102 #define ASCTXFCON_TXFITLOFF 8
103 #define ASCRXFCON_RXFEN 0x0001
104 #define ASCRXFCON_RXFFLU 0x0002
105 #define ASCRXFCON_RXFITLMASK 0x3F00
106 #define ASCRXFCON_RXFITLOFF 8
107 #define ASCFSTAT_RXFFLMASK 0x003F
108 #define ASCFSTAT_TXFFLMASK 0x3F00
109 #define ASCFSTAT_TXFREEMASK 0x3F000000
110 #define ASCFSTAT_TXFREEOFF 24
111
112 static void lqasc_tx_chars(struct uart_port *port);
113 static struct ltq_uart_port *lqasc_port[MAXPORTS];
114 static struct uart_driver lqasc_reg;
115 static DEFINE_SPINLOCK(ltq_asc_lock);
116
117 struct ltq_uart_port {
118 struct uart_port port;
119 /* clock used to derive divider */
120 struct clk *fpiclk;
121 /* clock gating of the ASC core */
122 struct clk *clk;
123 unsigned int tx_irq;
124 unsigned int rx_irq;
125 unsigned int err_irq;
126 };
127
128 static inline struct
129 ltq_uart_port *to_ltq_uart_port(struct uart_port *port)
130 {
131 return container_of(port, struct ltq_uart_port, port);
132 }
133
134 static void
135 lqasc_stop_tx(struct uart_port *port)
136 {
137 return;
138 }
139
140 static void
141 lqasc_start_tx(struct uart_port *port)
142 {
143 unsigned long flags;
144 spin_lock_irqsave(&ltq_asc_lock, flags);
145 lqasc_tx_chars(port);
146 spin_unlock_irqrestore(&ltq_asc_lock, flags);
147 return;
148 }
149
150 static void
151 lqasc_stop_rx(struct uart_port *port)
152 {
153 ltq_w32(ASCWHBSTATE_CLRREN, port->membase + LTQ_ASC_WHBSTATE);
154 }
155
156 static int
157 lqasc_rx_chars(struct uart_port *port)
158 {
159 struct tty_port *tport = &port->state->port;
160 unsigned int ch = 0, rsr = 0, fifocnt;
161
162 fifocnt = ltq_r32(port->membase + LTQ_ASC_FSTAT) & ASCFSTAT_RXFFLMASK;
163 while (fifocnt--) {
164 u8 flag = TTY_NORMAL;
165 ch = ltq_r8(port->membase + LTQ_ASC_RBUF);
166 rsr = (ltq_r32(port->membase + LTQ_ASC_STATE)
167 & ASCSTATE_ANY) | UART_DUMMY_UER_RX;
168 tty_flip_buffer_push(tport);
169 port->icount.rx++;
170
171 /*
172 * Note that the error handling code is
173 * out of the main execution path
174 */
175 if (rsr & ASCSTATE_ANY) {
176 if (rsr & ASCSTATE_PE) {
177 port->icount.parity++;
178 ltq_w32_mask(0, ASCWHBSTATE_CLRPE,
179 port->membase + LTQ_ASC_WHBSTATE);
180 } else if (rsr & ASCSTATE_FE) {
181 port->icount.frame++;
182 ltq_w32_mask(0, ASCWHBSTATE_CLRFE,
183 port->membase + LTQ_ASC_WHBSTATE);
184 }
185 if (rsr & ASCSTATE_ROE) {
186 port->icount.overrun++;
187 ltq_w32_mask(0, ASCWHBSTATE_CLRROE,
188 port->membase + LTQ_ASC_WHBSTATE);
189 }
190
191 rsr &= port->read_status_mask;
192
193 if (rsr & ASCSTATE_PE)
194 flag = TTY_PARITY;
195 else if (rsr & ASCSTATE_FE)
196 flag = TTY_FRAME;
197 }
198
199 if ((rsr & port->ignore_status_mask) == 0)
200 tty_insert_flip_char(tport, ch, flag);
201
202 if (rsr & ASCSTATE_ROE)
203 /*
204 * Overrun is special, since it's reported
205 * immediately, and doesn't affect the current
206 * character
207 */
208 tty_insert_flip_char(tport, 0, TTY_OVERRUN);
209 }
210
211 if (ch != 0)
212 tty_flip_buffer_push(tport);
213
214 return 0;
215 }
216
217 static void
218 lqasc_tx_chars(struct uart_port *port)
219 {
220 struct circ_buf *xmit = &port->state->xmit;
221 if (uart_tx_stopped(port)) {
222 lqasc_stop_tx(port);
223 return;
224 }
225
226 while (((ltq_r32(port->membase + LTQ_ASC_FSTAT) &
227 ASCFSTAT_TXFREEMASK) >> ASCFSTAT_TXFREEOFF) != 0) {
228 if (port->x_char) {
229 ltq_w8(port->x_char, port->membase + LTQ_ASC_TBUF);
230 port->icount.tx++;
231 port->x_char = 0;
232 continue;
233 }
234
235 if (uart_circ_empty(xmit))
236 break;
237
238 ltq_w8(port->state->xmit.buf[port->state->xmit.tail],
239 port->membase + LTQ_ASC_TBUF);
240 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
241 port->icount.tx++;
242 }
243
244 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
245 uart_write_wakeup(port);
246 }
247
248 static irqreturn_t
249 lqasc_tx_int(int irq, void *_port)
250 {
251 unsigned long flags;
252 struct uart_port *port = (struct uart_port *)_port;
253 spin_lock_irqsave(&ltq_asc_lock, flags);
254 ltq_w32(ASC_IRNCR_TIR, port->membase + LTQ_ASC_IRNCR);
255 spin_unlock_irqrestore(&ltq_asc_lock, flags);
256 lqasc_start_tx(port);
257 return IRQ_HANDLED;
258 }
259
260 static irqreturn_t
261 lqasc_err_int(int irq, void *_port)
262 {
263 unsigned long flags;
264 struct uart_port *port = (struct uart_port *)_port;
265 spin_lock_irqsave(&ltq_asc_lock, flags);
266 /* clear any pending interrupts */
267 ltq_w32_mask(0, ASCWHBSTATE_CLRPE | ASCWHBSTATE_CLRFE |
268 ASCWHBSTATE_CLRROE, port->membase + LTQ_ASC_WHBSTATE);
269 spin_unlock_irqrestore(&ltq_asc_lock, flags);
270 return IRQ_HANDLED;
271 }
272
273 static irqreturn_t
274 lqasc_rx_int(int irq, void *_port)
275 {
276 unsigned long flags;
277 struct uart_port *port = (struct uart_port *)_port;
278 spin_lock_irqsave(&ltq_asc_lock, flags);
279 ltq_w32(ASC_IRNCR_RIR, port->membase + LTQ_ASC_IRNCR);
280 lqasc_rx_chars(port);
281 spin_unlock_irqrestore(&ltq_asc_lock, flags);
282 return IRQ_HANDLED;
283 }
284
285 static unsigned int
286 lqasc_tx_empty(struct uart_port *port)
287 {
288 int status;
289 status = ltq_r32(port->membase + LTQ_ASC_FSTAT) & ASCFSTAT_TXFFLMASK;
290 return status ? 0 : TIOCSER_TEMT;
291 }
292
293 static unsigned int
294 lqasc_get_mctrl(struct uart_port *port)
295 {
296 return TIOCM_CTS | TIOCM_CAR | TIOCM_DSR;
297 }
298
299 static void
300 lqasc_set_mctrl(struct uart_port *port, u_int mctrl)
301 {
302 }
303
304 static void
305 lqasc_break_ctl(struct uart_port *port, int break_state)
306 {
307 }
308
309 static int
310 lqasc_startup(struct uart_port *port)
311 {
312 struct ltq_uart_port *ltq_port = to_ltq_uart_port(port);
313 int retval;
314
315 if (!IS_ERR(ltq_port->clk))
316 clk_enable(ltq_port->clk);
317 port->uartclk = clk_get_rate(ltq_port->fpiclk);
318
319 ltq_w32_mask(ASCCLC_DISS | ASCCLC_RMCMASK, (1 << ASCCLC_RMCOFFSET),
320 port->membase + LTQ_ASC_CLC);
321
322 ltq_w32(0, port->membase + LTQ_ASC_PISEL);
323 ltq_w32(
324 ((TXFIFO_FL << ASCTXFCON_TXFITLOFF) & ASCTXFCON_TXFITLMASK) |
325 ASCTXFCON_TXFEN | ASCTXFCON_TXFFLU,
326 port->membase + LTQ_ASC_TXFCON);
327 ltq_w32(
328 ((RXFIFO_FL << ASCRXFCON_RXFITLOFF) & ASCRXFCON_RXFITLMASK)
329 | ASCRXFCON_RXFEN | ASCRXFCON_RXFFLU,
330 port->membase + LTQ_ASC_RXFCON);
331 /* make sure other settings are written to hardware before
332 * setting enable bits
333 */
334 wmb();
335 ltq_w32_mask(0, ASCCON_M_8ASYNC | ASCCON_FEN | ASCCON_TOEN |
336 ASCCON_ROEN, port->membase + LTQ_ASC_CON);
337
338 retval = request_irq(ltq_port->tx_irq, lqasc_tx_int,
339 0, "asc_tx", port);
340 if (retval) {
341 pr_err("failed to request lqasc_tx_int\n");
342 return retval;
343 }
344
345 retval = request_irq(ltq_port->rx_irq, lqasc_rx_int,
346 0, "asc_rx", port);
347 if (retval) {
348 pr_err("failed to request lqasc_rx_int\n");
349 goto err1;
350 }
351
352 retval = request_irq(ltq_port->err_irq, lqasc_err_int,
353 0, "asc_err", port);
354 if (retval) {
355 pr_err("failed to request lqasc_err_int\n");
356 goto err2;
357 }
358
359 ltq_w32(ASC_IRNREN_RX | ASC_IRNREN_ERR | ASC_IRNREN_TX,
360 port->membase + LTQ_ASC_IRNREN);
361 return 0;
362
363 err2:
364 free_irq(ltq_port->rx_irq, port);
365 err1:
366 free_irq(ltq_port->tx_irq, port);
367 return retval;
368 }
369
370 static void
371 lqasc_shutdown(struct uart_port *port)
372 {
373 struct ltq_uart_port *ltq_port = to_ltq_uart_port(port);
374 free_irq(ltq_port->tx_irq, port);
375 free_irq(ltq_port->rx_irq, port);
376 free_irq(ltq_port->err_irq, port);
377
378 ltq_w32(0, port->membase + LTQ_ASC_CON);
379 ltq_w32_mask(ASCRXFCON_RXFEN, ASCRXFCON_RXFFLU,
380 port->membase + LTQ_ASC_RXFCON);
381 ltq_w32_mask(ASCTXFCON_TXFEN, ASCTXFCON_TXFFLU,
382 port->membase + LTQ_ASC_TXFCON);
383 if (!IS_ERR(ltq_port->clk))
384 clk_disable(ltq_port->clk);
385 }
386
387 static void
388 lqasc_set_termios(struct uart_port *port,
389 struct ktermios *new, struct ktermios *old)
390 {
391 unsigned int cflag;
392 unsigned int iflag;
393 unsigned int divisor;
394 unsigned int baud;
395 unsigned int con = 0;
396 unsigned long flags;
397
398 cflag = new->c_cflag;
399 iflag = new->c_iflag;
400
401 switch (cflag & CSIZE) {
402 case CS7:
403 con = ASCCON_M_7ASYNC;
404 break;
405
406 case CS5:
407 case CS6:
408 default:
409 new->c_cflag &= ~ CSIZE;
410 new->c_cflag |= CS8;
411 con = ASCCON_M_8ASYNC;
412 break;
413 }
414
415 cflag &= ~CMSPAR; /* Mark/Space parity is not supported */
416
417 if (cflag & CSTOPB)
418 con |= ASCCON_STP;
419
420 if (cflag & PARENB) {
421 if (!(cflag & PARODD))
422 con &= ~ASCCON_ODD;
423 else
424 con |= ASCCON_ODD;
425 }
426
427 port->read_status_mask = ASCSTATE_ROE;
428 if (iflag & INPCK)
429 port->read_status_mask |= ASCSTATE_FE | ASCSTATE_PE;
430
431 port->ignore_status_mask = 0;
432 if (iflag & IGNPAR)
433 port->ignore_status_mask |= ASCSTATE_FE | ASCSTATE_PE;
434
435 if (iflag & IGNBRK) {
436 /*
437 * If we're ignoring parity and break indicators,
438 * ignore overruns too (for real raw support).
439 */
440 if (iflag & IGNPAR)
441 port->ignore_status_mask |= ASCSTATE_ROE;
442 }
443
444 if ((cflag & CREAD) == 0)
445 port->ignore_status_mask |= UART_DUMMY_UER_RX;
446
447 /* set error signals - framing, parity and overrun, enable receiver */
448 con |= ASCCON_FEN | ASCCON_TOEN | ASCCON_ROEN;
449
450 spin_lock_irqsave(&ltq_asc_lock, flags);
451
452 /* set up CON */
453 ltq_w32_mask(0, con, port->membase + LTQ_ASC_CON);
454
455 /* Set baud rate - take a divider of 2 into account */
456 baud = uart_get_baud_rate(port, new, old, 0, port->uartclk / 16);
457 divisor = uart_get_divisor(port, baud);
458 divisor = divisor / 2 - 1;
459
460 /* disable the baudrate generator */
461 ltq_w32_mask(ASCCON_R, 0, port->membase + LTQ_ASC_CON);
462
463 /* make sure the fractional divider is off */
464 ltq_w32_mask(ASCCON_FDE, 0, port->membase + LTQ_ASC_CON);
465
466 /* set up to use divisor of 2 */
467 ltq_w32_mask(ASCCON_BRS, 0, port->membase + LTQ_ASC_CON);
468
469 /* now we can write the new baudrate into the register */
470 ltq_w32(divisor, port->membase + LTQ_ASC_BG);
471
472 /* turn the baudrate generator back on */
473 ltq_w32_mask(0, ASCCON_R, port->membase + LTQ_ASC_CON);
474
475 /* enable rx */
476 ltq_w32(ASCWHBSTATE_SETREN, port->membase + LTQ_ASC_WHBSTATE);
477
478 spin_unlock_irqrestore(&ltq_asc_lock, flags);
479
480 /* Don't rewrite B0 */
481 if (tty_termios_baud_rate(new))
482 tty_termios_encode_baud_rate(new, baud, baud);
483
484 uart_update_timeout(port, cflag, baud);
485 }
486
487 static const char*
488 lqasc_type(struct uart_port *port)
489 {
490 if (port->type == PORT_LTQ_ASC)
491 return DRVNAME;
492 else
493 return NULL;
494 }
495
496 static void
497 lqasc_release_port(struct uart_port *port)
498 {
499 struct platform_device *pdev = to_platform_device(port->dev);
500
501 if (port->flags & UPF_IOREMAP) {
502 devm_iounmap(&pdev->dev, port->membase);
503 port->membase = NULL;
504 }
505 }
506
507 static int
508 lqasc_request_port(struct uart_port *port)
509 {
510 struct platform_device *pdev = to_platform_device(port->dev);
511 struct resource *res;
512 int size;
513
514 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
515 if (!res) {
516 dev_err(&pdev->dev, "cannot obtain I/O memory region");
517 return -ENODEV;
518 }
519 size = resource_size(res);
520
521 res = devm_request_mem_region(&pdev->dev, res->start,
522 size, dev_name(&pdev->dev));
523 if (!res) {
524 dev_err(&pdev->dev, "cannot request I/O memory region");
525 return -EBUSY;
526 }
527
528 if (port->flags & UPF_IOREMAP) {
529 port->membase = devm_ioremap_nocache(&pdev->dev,
530 port->mapbase, size);
531 if (port->membase == NULL)
532 return -ENOMEM;
533 }
534 return 0;
535 }
536
537 static void
538 lqasc_config_port(struct uart_port *port, int flags)
539 {
540 if (flags & UART_CONFIG_TYPE) {
541 port->type = PORT_LTQ_ASC;
542 lqasc_request_port(port);
543 }
544 }
545
546 static int
547 lqasc_verify_port(struct uart_port *port,
548 struct serial_struct *ser)
549 {
550 int ret = 0;
551 if (ser->type != PORT_UNKNOWN && ser->type != PORT_LTQ_ASC)
552 ret = -EINVAL;
553 if (ser->irq < 0 || ser->irq >= NR_IRQS)
554 ret = -EINVAL;
555 if (ser->baud_base < 9600)
556 ret = -EINVAL;
557 return ret;
558 }
559
560 static struct uart_ops lqasc_pops = {
561 .tx_empty = lqasc_tx_empty,
562 .set_mctrl = lqasc_set_mctrl,
563 .get_mctrl = lqasc_get_mctrl,
564 .stop_tx = lqasc_stop_tx,
565 .start_tx = lqasc_start_tx,
566 .stop_rx = lqasc_stop_rx,
567 .break_ctl = lqasc_break_ctl,
568 .startup = lqasc_startup,
569 .shutdown = lqasc_shutdown,
570 .set_termios = lqasc_set_termios,
571 .type = lqasc_type,
572 .release_port = lqasc_release_port,
573 .request_port = lqasc_request_port,
574 .config_port = lqasc_config_port,
575 .verify_port = lqasc_verify_port,
576 };
577
578 static void
579 lqasc_console_putchar(struct uart_port *port, int ch)
580 {
581 int fifofree;
582
583 if (!port->membase)
584 return;
585
586 do {
587 fifofree = (ltq_r32(port->membase + LTQ_ASC_FSTAT)
588 & ASCFSTAT_TXFREEMASK) >> ASCFSTAT_TXFREEOFF;
589 } while (fifofree == 0);
590 ltq_w8(ch, port->membase + LTQ_ASC_TBUF);
591 }
592
593
594 static void
595 lqasc_console_write(struct console *co, const char *s, u_int count)
596 {
597 struct ltq_uart_port *ltq_port;
598 struct uart_port *port;
599 unsigned long flags;
600
601 if (co->index >= MAXPORTS)
602 return;
603
604 ltq_port = lqasc_port[co->index];
605 if (!ltq_port)
606 return;
607
608 port = &ltq_port->port;
609
610 spin_lock_irqsave(&ltq_asc_lock, flags);
611 uart_console_write(port, s, count, lqasc_console_putchar);
612 spin_unlock_irqrestore(&ltq_asc_lock, flags);
613 }
614
615 static int __init
616 lqasc_console_setup(struct console *co, char *options)
617 {
618 struct ltq_uart_port *ltq_port;
619 struct uart_port *port;
620 int baud = 115200;
621 int bits = 8;
622 int parity = 'n';
623 int flow = 'n';
624
625 if (co->index >= MAXPORTS)
626 return -ENODEV;
627
628 ltq_port = lqasc_port[co->index];
629 if (!ltq_port)
630 return -ENODEV;
631
632 port = &ltq_port->port;
633
634 if (!IS_ERR(ltq_port->clk))
635 clk_enable(ltq_port->clk);
636
637 port->uartclk = clk_get_rate(ltq_port->fpiclk);
638
639 if (options)
640 uart_parse_options(options, &baud, &parity, &bits, &flow);
641 return uart_set_options(port, co, baud, parity, bits, flow);
642 }
643
644 static struct console lqasc_console = {
645 .name = "ttyLTQ",
646 .write = lqasc_console_write,
647 .device = uart_console_device,
648 .setup = lqasc_console_setup,
649 .flags = CON_PRINTBUFFER,
650 .index = -1,
651 .data = &lqasc_reg,
652 };
653
654 static int __init
655 lqasc_console_init(void)
656 {
657 register_console(&lqasc_console);
658 return 0;
659 }
660 console_initcall(lqasc_console_init);
661
662 static struct uart_driver lqasc_reg = {
663 .owner = THIS_MODULE,
664 .driver_name = DRVNAME,
665 .dev_name = "ttyLTQ",
666 .major = 0,
667 .minor = 0,
668 .nr = MAXPORTS,
669 .cons = &lqasc_console,
670 };
671
672 static int __init
673 lqasc_probe(struct platform_device *pdev)
674 {
675 struct device_node *node = pdev->dev.of_node;
676 struct ltq_uart_port *ltq_port;
677 struct uart_port *port;
678 struct resource *mmres, irqres[3];
679 int line = 0;
680 int ret;
681
682 mmres = platform_get_resource(pdev, IORESOURCE_MEM, 0);
683 ret = of_irq_to_resource_table(node, irqres, 3);
684 if (!mmres || (ret != 3)) {
685 dev_err(&pdev->dev,
686 "failed to get memory/irq for serial port\n");
687 return -ENODEV;
688 }
689
690 /* check if this is the console port */
691 if (mmres->start != CPHYSADDR(LTQ_EARLY_ASC))
692 line = 1;
693
694 if (lqasc_port[line]) {
695 dev_err(&pdev->dev, "port %d already allocated\n", line);
696 return -EBUSY;
697 }
698
699 ltq_port = devm_kzalloc(&pdev->dev, sizeof(struct ltq_uart_port),
700 GFP_KERNEL);
701 if (!ltq_port)
702 return -ENOMEM;
703
704 port = &ltq_port->port;
705
706 port->iotype = SERIAL_IO_MEM;
707 port->flags = UPF_BOOT_AUTOCONF | UPF_IOREMAP;
708 port->ops = &lqasc_pops;
709 port->fifosize = 16;
710 port->type = PORT_LTQ_ASC,
711 port->line = line;
712 port->dev = &pdev->dev;
713 /* unused, just to be backward-compatible */
714 port->irq = irqres[0].start;
715 port->mapbase = mmres->start;
716
717 ltq_port->fpiclk = clk_get_fpi();
718 if (IS_ERR(ltq_port->fpiclk)) {
719 pr_err("failed to get fpi clk\n");
720 return -ENOENT;
721 }
722
723 /* not all asc ports have clock gates, lets ignore the return code */
724 ltq_port->clk = clk_get(&pdev->dev, NULL);
725
726 ltq_port->tx_irq = irqres[0].start;
727 ltq_port->rx_irq = irqres[1].start;
728 ltq_port->err_irq = irqres[2].start;
729
730 lqasc_port[line] = ltq_port;
731 platform_set_drvdata(pdev, ltq_port);
732
733 ret = uart_add_one_port(&lqasc_reg, port);
734
735 return ret;
736 }
737
738 static const struct of_device_id ltq_asc_match[] = {
739 { .compatible = DRVNAME },
740 {},
741 };
742
743 static struct platform_driver lqasc_driver = {
744 .driver = {
745 .name = DRVNAME,
746 .of_match_table = ltq_asc_match,
747 },
748 };
749
750 int __init
751 init_lqasc(void)
752 {
753 int ret;
754
755 ret = uart_register_driver(&lqasc_reg);
756 if (ret != 0)
757 return ret;
758
759 ret = platform_driver_probe(&lqasc_driver, lqasc_probe);
760 if (ret != 0)
761 uart_unregister_driver(&lqasc_reg);
762
763 return ret;
764 }
765 device_initcall(init_lqasc);
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