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1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Based on drivers/char/serial.c, by Linus Torvalds, Theodore Ts'o.
4 *
5 * Copyright (C) 2004 Infineon IFAP DC COM CPE
6 * Copyright (C) 2007 Felix Fietkau <nbd@openwrt.org>
7 * Copyright (C) 2007 John Crispin <john@phrozen.org>
8 * Copyright (C) 2010 Thomas Langer, <thomas.langer@lantiq.com>
9 */
10
11#include <linux/slab.h>
12#include <linux/ioport.h>
13#include <linux/init.h>
14#include <linux/console.h>
15#include <linux/sysrq.h>
16#include <linux/device.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/of_platform.h>
22#include <linux/of_address.h>
23#include <linux/of_irq.h>
24#include <linux/io.h>
25#include <linux/clk.h>
26#include <linux/gpio.h>
27
28#include <lantiq_soc.h>
29
30#define PORT_LTQ_ASC 111
31#define MAXPORTS 2
32#define UART_DUMMY_UER_RX 1
33#define DRVNAME "lantiq,asc"
34#ifdef __BIG_ENDIAN
35#define LTQ_ASC_TBUF (0x0020 + 3)
36#define LTQ_ASC_RBUF (0x0024 + 3)
37#else
38#define LTQ_ASC_TBUF 0x0020
39#define LTQ_ASC_RBUF 0x0024
40#endif
41#define LTQ_ASC_FSTAT 0x0048
42#define LTQ_ASC_WHBSTATE 0x0018
43#define LTQ_ASC_STATE 0x0014
44#define LTQ_ASC_IRNCR 0x00F8
45#define LTQ_ASC_CLC 0x0000
46#define LTQ_ASC_ID 0x0008
47#define LTQ_ASC_PISEL 0x0004
48#define LTQ_ASC_TXFCON 0x0044
49#define LTQ_ASC_RXFCON 0x0040
50#define LTQ_ASC_CON 0x0010
51#define LTQ_ASC_BG 0x0050
52#define LTQ_ASC_IRNREN 0x00F4
53
54#define ASC_IRNREN_TX 0x1
55#define ASC_IRNREN_RX 0x2
56#define ASC_IRNREN_ERR 0x4
57#define ASC_IRNREN_TX_BUF 0x8
58#define ASC_IRNCR_TIR 0x1
59#define ASC_IRNCR_RIR 0x2
60#define ASC_IRNCR_EIR 0x4
61
62#define ASCOPT_CSIZE 0x3
63#define TXFIFO_FL 1
64#define RXFIFO_FL 1
65#define ASCCLC_DISS 0x2
66#define ASCCLC_RMCMASK 0x0000FF00
67#define ASCCLC_RMCOFFSET 8
68#define ASCCON_M_8ASYNC 0x0
69#define ASCCON_M_7ASYNC 0x2
70#define ASCCON_ODD 0x00000020
71#define ASCCON_STP 0x00000080
72#define ASCCON_BRS 0x00000100
73#define ASCCON_FDE 0x00000200
74#define ASCCON_R 0x00008000
75#define ASCCON_FEN 0x00020000
76#define ASCCON_ROEN 0x00080000
77#define ASCCON_TOEN 0x00100000
78#define ASCSTATE_PE 0x00010000
79#define ASCSTATE_FE 0x00020000
80#define ASCSTATE_ROE 0x00080000
81#define ASCSTATE_ANY (ASCSTATE_ROE|ASCSTATE_PE|ASCSTATE_FE)
82#define ASCWHBSTATE_CLRREN 0x00000001
83#define ASCWHBSTATE_SETREN 0x00000002
84#define ASCWHBSTATE_CLRPE 0x00000004
85#define ASCWHBSTATE_CLRFE 0x00000008
86#define ASCWHBSTATE_CLRROE 0x00000020
87#define ASCTXFCON_TXFEN 0x0001
88#define ASCTXFCON_TXFFLU 0x0002
89#define ASCTXFCON_TXFITLMASK 0x3F00
90#define ASCTXFCON_TXFITLOFF 8
91#define ASCRXFCON_RXFEN 0x0001
92#define ASCRXFCON_RXFFLU 0x0002
93#define ASCRXFCON_RXFITLMASK 0x3F00
94#define ASCRXFCON_RXFITLOFF 8
95#define ASCFSTAT_RXFFLMASK 0x003F
96#define ASCFSTAT_TXFFLMASK 0x3F00
97#define ASCFSTAT_TXFREEMASK 0x3F000000
98#define ASCFSTAT_TXFREEOFF 24
99
100static void lqasc_tx_chars(struct uart_port *port);
101static struct ltq_uart_port *lqasc_port[MAXPORTS];
102static struct uart_driver lqasc_reg;
103static DEFINE_SPINLOCK(ltq_asc_lock);
104
105struct ltq_uart_port {
106 struct uart_port port;
107 /* clock used to derive divider */
108 struct clk *fpiclk;
109 /* clock gating of the ASC core */
110 struct clk *clk;
111 unsigned int tx_irq;
112 unsigned int rx_irq;
113 unsigned int err_irq;
114};
115
116static inline struct
117ltq_uart_port *to_ltq_uart_port(struct uart_port *port)
118{
119 return container_of(port, struct ltq_uart_port, port);
120}
121
122static void
123lqasc_stop_tx(struct uart_port *port)
124{
125 return;
126}
127
128static void
129lqasc_start_tx(struct uart_port *port)
130{
131 unsigned long flags;
132 spin_lock_irqsave(<q_asc_lock, flags);
133 lqasc_tx_chars(port);
134 spin_unlock_irqrestore(<q_asc_lock, flags);
135 return;
136}
137
138static void
139lqasc_stop_rx(struct uart_port *port)
140{
141 ltq_w32(ASCWHBSTATE_CLRREN, port->membase + LTQ_ASC_WHBSTATE);
142}
143
144static int
145lqasc_rx_chars(struct uart_port *port)
146{
147 struct tty_port *tport = &port->state->port;
148 unsigned int ch = 0, rsr = 0, fifocnt;
149
150 fifocnt = ltq_r32(port->membase + LTQ_ASC_FSTAT) & ASCFSTAT_RXFFLMASK;
151 while (fifocnt--) {
152 u8 flag = TTY_NORMAL;
153 ch = ltq_r8(port->membase + LTQ_ASC_RBUF);
154 rsr = (ltq_r32(port->membase + LTQ_ASC_STATE)
155 & ASCSTATE_ANY) | UART_DUMMY_UER_RX;
156 tty_flip_buffer_push(tport);
157 port->icount.rx++;
158
159 /*
160 * Note that the error handling code is
161 * out of the main execution path
162 */
163 if (rsr & ASCSTATE_ANY) {
164 if (rsr & ASCSTATE_PE) {
165 port->icount.parity++;
166 ltq_w32_mask(0, ASCWHBSTATE_CLRPE,
167 port->membase + LTQ_ASC_WHBSTATE);
168 } else if (rsr & ASCSTATE_FE) {
169 port->icount.frame++;
170 ltq_w32_mask(0, ASCWHBSTATE_CLRFE,
171 port->membase + LTQ_ASC_WHBSTATE);
172 }
173 if (rsr & ASCSTATE_ROE) {
174 port->icount.overrun++;
175 ltq_w32_mask(0, ASCWHBSTATE_CLRROE,
176 port->membase + LTQ_ASC_WHBSTATE);
177 }
178
179 rsr &= port->read_status_mask;
180
181 if (rsr & ASCSTATE_PE)
182 flag = TTY_PARITY;
183 else if (rsr & ASCSTATE_FE)
184 flag = TTY_FRAME;
185 }
186
187 if ((rsr & port->ignore_status_mask) == 0)
188 tty_insert_flip_char(tport, ch, flag);
189
190 if (rsr & ASCSTATE_ROE)
191 /*
192 * Overrun is special, since it's reported
193 * immediately, and doesn't affect the current
194 * character
195 */
196 tty_insert_flip_char(tport, 0, TTY_OVERRUN);
197 }
198
199 if (ch != 0)
200 tty_flip_buffer_push(tport);
201
202 return 0;
203}
204
205static void
206lqasc_tx_chars(struct uart_port *port)
207{
208 struct circ_buf *xmit = &port->state->xmit;
209 if (uart_tx_stopped(port)) {
210 lqasc_stop_tx(port);
211 return;
212 }
213
214 while (((ltq_r32(port->membase + LTQ_ASC_FSTAT) &
215 ASCFSTAT_TXFREEMASK) >> ASCFSTAT_TXFREEOFF) != 0) {
216 if (port->x_char) {
217 ltq_w8(port->x_char, port->membase + LTQ_ASC_TBUF);
218 port->icount.tx++;
219 port->x_char = 0;
220 continue;
221 }
222
223 if (uart_circ_empty(xmit))
224 break;
225
226 ltq_w8(port->state->xmit.buf[port->state->xmit.tail],
227 port->membase + LTQ_ASC_TBUF);
228 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
229 port->icount.tx++;
230 }
231
232 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
233 uart_write_wakeup(port);
234}
235
236static irqreturn_t
237lqasc_tx_int(int irq, void *_port)
238{
239 unsigned long flags;
240 struct uart_port *port = (struct uart_port *)_port;
241 spin_lock_irqsave(<q_asc_lock, flags);
242 ltq_w32(ASC_IRNCR_TIR, port->membase + LTQ_ASC_IRNCR);
243 spin_unlock_irqrestore(<q_asc_lock, flags);
244 lqasc_start_tx(port);
245 return IRQ_HANDLED;
246}
247
248static irqreturn_t
249lqasc_err_int(int irq, void *_port)
250{
251 unsigned long flags;
252 struct uart_port *port = (struct uart_port *)_port;
253 spin_lock_irqsave(<q_asc_lock, flags);
254 /* clear any pending interrupts */
255 ltq_w32_mask(0, ASCWHBSTATE_CLRPE | ASCWHBSTATE_CLRFE |
256 ASCWHBSTATE_CLRROE, port->membase + LTQ_ASC_WHBSTATE);
257 spin_unlock_irqrestore(<q_asc_lock, flags);
258 return IRQ_HANDLED;
259}
260
261static irqreturn_t
262lqasc_rx_int(int irq, void *_port)
263{
264 unsigned long flags;
265 struct uart_port *port = (struct uart_port *)_port;
266 spin_lock_irqsave(<q_asc_lock, flags);
267 ltq_w32(ASC_IRNCR_RIR, port->membase + LTQ_ASC_IRNCR);
268 lqasc_rx_chars(port);
269 spin_unlock_irqrestore(<q_asc_lock, flags);
270 return IRQ_HANDLED;
271}
272
273static unsigned int
274lqasc_tx_empty(struct uart_port *port)
275{
276 int status;
277 status = ltq_r32(port->membase + LTQ_ASC_FSTAT) & ASCFSTAT_TXFFLMASK;
278 return status ? 0 : TIOCSER_TEMT;
279}
280
281static unsigned int
282lqasc_get_mctrl(struct uart_port *port)
283{
284 return TIOCM_CTS | TIOCM_CAR | TIOCM_DSR;
285}
286
287static void
288lqasc_set_mctrl(struct uart_port *port, u_int mctrl)
289{
290}
291
292static void
293lqasc_break_ctl(struct uart_port *port, int break_state)
294{
295}
296
297static int
298lqasc_startup(struct uart_port *port)
299{
300 struct ltq_uart_port *ltq_port = to_ltq_uart_port(port);
301 int retval;
302
303 if (!IS_ERR(ltq_port->clk))
304 clk_enable(ltq_port->clk);
305 port->uartclk = clk_get_rate(ltq_port->fpiclk);
306
307 ltq_w32_mask(ASCCLC_DISS | ASCCLC_RMCMASK, (1 << ASCCLC_RMCOFFSET),
308 port->membase + LTQ_ASC_CLC);
309
310 ltq_w32(0, port->membase + LTQ_ASC_PISEL);
311 ltq_w32(
312 ((TXFIFO_FL << ASCTXFCON_TXFITLOFF) & ASCTXFCON_TXFITLMASK) |
313 ASCTXFCON_TXFEN | ASCTXFCON_TXFFLU,
314 port->membase + LTQ_ASC_TXFCON);
315 ltq_w32(
316 ((RXFIFO_FL << ASCRXFCON_RXFITLOFF) & ASCRXFCON_RXFITLMASK)
317 | ASCRXFCON_RXFEN | ASCRXFCON_RXFFLU,
318 port->membase + LTQ_ASC_RXFCON);
319 /* make sure other settings are written to hardware before
320 * setting enable bits
321 */
322 wmb();
323 ltq_w32_mask(0, ASCCON_M_8ASYNC | ASCCON_FEN | ASCCON_TOEN |
324 ASCCON_ROEN, port->membase + LTQ_ASC_CON);
325
326 retval = request_irq(ltq_port->tx_irq, lqasc_tx_int,
327 0, "asc_tx", port);
328 if (retval) {
329 pr_err("failed to request lqasc_tx_int\n");
330 return retval;
331 }
332
333 retval = request_irq(ltq_port->rx_irq, lqasc_rx_int,
334 0, "asc_rx", port);
335 if (retval) {
336 pr_err("failed to request lqasc_rx_int\n");
337 goto err1;
338 }
339
340 retval = request_irq(ltq_port->err_irq, lqasc_err_int,
341 0, "asc_err", port);
342 if (retval) {
343 pr_err("failed to request lqasc_err_int\n");
344 goto err2;
345 }
346
347 ltq_w32(ASC_IRNREN_RX | ASC_IRNREN_ERR | ASC_IRNREN_TX,
348 port->membase + LTQ_ASC_IRNREN);
349 return 0;
350
351err2:
352 free_irq(ltq_port->rx_irq, port);
353err1:
354 free_irq(ltq_port->tx_irq, port);
355 return retval;
356}
357
358static void
359lqasc_shutdown(struct uart_port *port)
360{
361 struct ltq_uart_port *ltq_port = to_ltq_uart_port(port);
362 free_irq(ltq_port->tx_irq, port);
363 free_irq(ltq_port->rx_irq, port);
364 free_irq(ltq_port->err_irq, port);
365
366 ltq_w32(0, port->membase + LTQ_ASC_CON);
367 ltq_w32_mask(ASCRXFCON_RXFEN, ASCRXFCON_RXFFLU,
368 port->membase + LTQ_ASC_RXFCON);
369 ltq_w32_mask(ASCTXFCON_TXFEN, ASCTXFCON_TXFFLU,
370 port->membase + LTQ_ASC_TXFCON);
371 if (!IS_ERR(ltq_port->clk))
372 clk_disable(ltq_port->clk);
373}
374
375static void
376lqasc_set_termios(struct uart_port *port,
377 struct ktermios *new, struct ktermios *old)
378{
379 unsigned int cflag;
380 unsigned int iflag;
381 unsigned int divisor;
382 unsigned int baud;
383 unsigned int con = 0;
384 unsigned long flags;
385
386 cflag = new->c_cflag;
387 iflag = new->c_iflag;
388
389 switch (cflag & CSIZE) {
390 case CS7:
391 con = ASCCON_M_7ASYNC;
392 break;
393
394 case CS5:
395 case CS6:
396 default:
397 new->c_cflag &= ~ CSIZE;
398 new->c_cflag |= CS8;
399 con = ASCCON_M_8ASYNC;
400 break;
401 }
402
403 cflag &= ~CMSPAR; /* Mark/Space parity is not supported */
404
405 if (cflag & CSTOPB)
406 con |= ASCCON_STP;
407
408 if (cflag & PARENB) {
409 if (!(cflag & PARODD))
410 con &= ~ASCCON_ODD;
411 else
412 con |= ASCCON_ODD;
413 }
414
415 port->read_status_mask = ASCSTATE_ROE;
416 if (iflag & INPCK)
417 port->read_status_mask |= ASCSTATE_FE | ASCSTATE_PE;
418
419 port->ignore_status_mask = 0;
420 if (iflag & IGNPAR)
421 port->ignore_status_mask |= ASCSTATE_FE | ASCSTATE_PE;
422
423 if (iflag & IGNBRK) {
424 /*
425 * If we're ignoring parity and break indicators,
426 * ignore overruns too (for real raw support).
427 */
428 if (iflag & IGNPAR)
429 port->ignore_status_mask |= ASCSTATE_ROE;
430 }
431
432 if ((cflag & CREAD) == 0)
433 port->ignore_status_mask |= UART_DUMMY_UER_RX;
434
435 /* set error signals - framing, parity and overrun, enable receiver */
436 con |= ASCCON_FEN | ASCCON_TOEN | ASCCON_ROEN;
437
438 spin_lock_irqsave(<q_asc_lock, flags);
439
440 /* set up CON */
441 ltq_w32_mask(0, con, port->membase + LTQ_ASC_CON);
442
443 /* Set baud rate - take a divider of 2 into account */
444 baud = uart_get_baud_rate(port, new, old, 0, port->uartclk / 16);
445 divisor = uart_get_divisor(port, baud);
446 divisor = divisor / 2 - 1;
447
448 /* disable the baudrate generator */
449 ltq_w32_mask(ASCCON_R, 0, port->membase + LTQ_ASC_CON);
450
451 /* make sure the fractional divider is off */
452 ltq_w32_mask(ASCCON_FDE, 0, port->membase + LTQ_ASC_CON);
453
454 /* set up to use divisor of 2 */
455 ltq_w32_mask(ASCCON_BRS, 0, port->membase + LTQ_ASC_CON);
456
457 /* now we can write the new baudrate into the register */
458 ltq_w32(divisor, port->membase + LTQ_ASC_BG);
459
460 /* turn the baudrate generator back on */
461 ltq_w32_mask(0, ASCCON_R, port->membase + LTQ_ASC_CON);
462
463 /* enable rx */
464 ltq_w32(ASCWHBSTATE_SETREN, port->membase + LTQ_ASC_WHBSTATE);
465
466 spin_unlock_irqrestore(<q_asc_lock, flags);
467
468 /* Don't rewrite B0 */
469 if (tty_termios_baud_rate(new))
470 tty_termios_encode_baud_rate(new, baud, baud);
471
472 uart_update_timeout(port, cflag, baud);
473}
474
475static const char*
476lqasc_type(struct uart_port *port)
477{
478 if (port->type == PORT_LTQ_ASC)
479 return DRVNAME;
480 else
481 return NULL;
482}
483
484static void
485lqasc_release_port(struct uart_port *port)
486{
487 struct platform_device *pdev = to_platform_device(port->dev);
488
489 if (port->flags & UPF_IOREMAP) {
490 devm_iounmap(&pdev->dev, port->membase);
491 port->membase = NULL;
492 }
493}
494
495static int
496lqasc_request_port(struct uart_port *port)
497{
498 struct platform_device *pdev = to_platform_device(port->dev);
499 struct resource *res;
500 int size;
501
502 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
503 if (!res) {
504 dev_err(&pdev->dev, "cannot obtain I/O memory region");
505 return -ENODEV;
506 }
507 size = resource_size(res);
508
509 res = devm_request_mem_region(&pdev->dev, res->start,
510 size, dev_name(&pdev->dev));
511 if (!res) {
512 dev_err(&pdev->dev, "cannot request I/O memory region");
513 return -EBUSY;
514 }
515
516 if (port->flags & UPF_IOREMAP) {
517 port->membase = devm_ioremap_nocache(&pdev->dev,
518 port->mapbase, size);
519 if (port->membase == NULL)
520 return -ENOMEM;
521 }
522 return 0;
523}
524
525static void
526lqasc_config_port(struct uart_port *port, int flags)
527{
528 if (flags & UART_CONFIG_TYPE) {
529 port->type = PORT_LTQ_ASC;
530 lqasc_request_port(port);
531 }
532}
533
534static int
535lqasc_verify_port(struct uart_port *port,
536 struct serial_struct *ser)
537{
538 int ret = 0;
539 if (ser->type != PORT_UNKNOWN && ser->type != PORT_LTQ_ASC)
540 ret = -EINVAL;
541 if (ser->irq < 0 || ser->irq >= NR_IRQS)
542 ret = -EINVAL;
543 if (ser->baud_base < 9600)
544 ret = -EINVAL;
545 return ret;
546}
547
548static const struct uart_ops lqasc_pops = {
549 .tx_empty = lqasc_tx_empty,
550 .set_mctrl = lqasc_set_mctrl,
551 .get_mctrl = lqasc_get_mctrl,
552 .stop_tx = lqasc_stop_tx,
553 .start_tx = lqasc_start_tx,
554 .stop_rx = lqasc_stop_rx,
555 .break_ctl = lqasc_break_ctl,
556 .startup = lqasc_startup,
557 .shutdown = lqasc_shutdown,
558 .set_termios = lqasc_set_termios,
559 .type = lqasc_type,
560 .release_port = lqasc_release_port,
561 .request_port = lqasc_request_port,
562 .config_port = lqasc_config_port,
563 .verify_port = lqasc_verify_port,
564};
565
566static void
567lqasc_console_putchar(struct uart_port *port, int ch)
568{
569 int fifofree;
570
571 if (!port->membase)
572 return;
573
574 do {
575 fifofree = (ltq_r32(port->membase + LTQ_ASC_FSTAT)
576 & ASCFSTAT_TXFREEMASK) >> ASCFSTAT_TXFREEOFF;
577 } while (fifofree == 0);
578 ltq_w8(ch, port->membase + LTQ_ASC_TBUF);
579}
580
581static void lqasc_serial_port_write(struct uart_port *port, const char *s,
582 u_int count)
583{
584 unsigned long flags;
585
586 spin_lock_irqsave(<q_asc_lock, flags);
587 uart_console_write(port, s, count, lqasc_console_putchar);
588 spin_unlock_irqrestore(<q_asc_lock, flags);
589}
590
591static void
592lqasc_console_write(struct console *co, const char *s, u_int count)
593{
594 struct ltq_uart_port *ltq_port;
595
596 if (co->index >= MAXPORTS)
597 return;
598
599 ltq_port = lqasc_port[co->index];
600 if (!ltq_port)
601 return;
602
603 lqasc_serial_port_write(<q_port->port, s, count);
604}
605
606static int __init
607lqasc_console_setup(struct console *co, char *options)
608{
609 struct ltq_uart_port *ltq_port;
610 struct uart_port *port;
611 int baud = 115200;
612 int bits = 8;
613 int parity = 'n';
614 int flow = 'n';
615
616 if (co->index >= MAXPORTS)
617 return -ENODEV;
618
619 ltq_port = lqasc_port[co->index];
620 if (!ltq_port)
621 return -ENODEV;
622
623 port = <q_port->port;
624
625 if (!IS_ERR(ltq_port->clk))
626 clk_enable(ltq_port->clk);
627
628 port->uartclk = clk_get_rate(ltq_port->fpiclk);
629
630 if (options)
631 uart_parse_options(options, &baud, &parity, &bits, &flow);
632 return uart_set_options(port, co, baud, parity, bits, flow);
633}
634
635static struct console lqasc_console = {
636 .name = "ttyLTQ",
637 .write = lqasc_console_write,
638 .device = uart_console_device,
639 .setup = lqasc_console_setup,
640 .flags = CON_PRINTBUFFER,
641 .index = -1,
642 .data = &lqasc_reg,
643};
644
645static int __init
646lqasc_console_init(void)
647{
648 register_console(&lqasc_console);
649 return 0;
650}
651console_initcall(lqasc_console_init);
652
653static void lqasc_serial_early_console_write(struct console *co,
654 const char *s,
655 u_int count)
656{
657 struct earlycon_device *dev = co->data;
658
659 lqasc_serial_port_write(&dev->port, s, count);
660}
661
662static int __init
663lqasc_serial_early_console_setup(struct earlycon_device *device,
664 const char *opt)
665{
666 if (!device->port.membase)
667 return -ENODEV;
668
669 device->con->write = lqasc_serial_early_console_write;
670 return 0;
671}
672OF_EARLYCON_DECLARE(lantiq, DRVNAME, lqasc_serial_early_console_setup);
673
674static struct uart_driver lqasc_reg = {
675 .owner = THIS_MODULE,
676 .driver_name = DRVNAME,
677 .dev_name = "ttyLTQ",
678 .major = 0,
679 .minor = 0,
680 .nr = MAXPORTS,
681 .cons = &lqasc_console,
682};
683
684static int __init
685lqasc_probe(struct platform_device *pdev)
686{
687 struct device_node *node = pdev->dev.of_node;
688 struct ltq_uart_port *ltq_port;
689 struct uart_port *port;
690 struct resource *mmres, irqres[3];
691 int line = 0;
692 int ret;
693
694 mmres = platform_get_resource(pdev, IORESOURCE_MEM, 0);
695 ret = of_irq_to_resource_table(node, irqres, 3);
696 if (!mmres || (ret != 3)) {
697 dev_err(&pdev->dev,
698 "failed to get memory/irq for serial port\n");
699 return -ENODEV;
700 }
701
702 /* check if this is the console port */
703 if (mmres->start != CPHYSADDR(LTQ_EARLY_ASC))
704 line = 1;
705
706 if (lqasc_port[line]) {
707 dev_err(&pdev->dev, "port %d already allocated\n", line);
708 return -EBUSY;
709 }
710
711 ltq_port = devm_kzalloc(&pdev->dev, sizeof(struct ltq_uart_port),
712 GFP_KERNEL);
713 if (!ltq_port)
714 return -ENOMEM;
715
716 port = <q_port->port;
717
718 port->iotype = SERIAL_IO_MEM;
719 port->flags = UPF_BOOT_AUTOCONF | UPF_IOREMAP;
720 port->ops = &lqasc_pops;
721 port->fifosize = 16;
722 port->type = PORT_LTQ_ASC,
723 port->line = line;
724 port->dev = &pdev->dev;
725 /* unused, just to be backward-compatible */
726 port->irq = irqres[0].start;
727 port->mapbase = mmres->start;
728
729 ltq_port->fpiclk = clk_get_fpi();
730 if (IS_ERR(ltq_port->fpiclk)) {
731 pr_err("failed to get fpi clk\n");
732 return -ENOENT;
733 }
734
735 /* not all asc ports have clock gates, lets ignore the return code */
736 ltq_port->clk = clk_get(&pdev->dev, NULL);
737
738 ltq_port->tx_irq = irqres[0].start;
739 ltq_port->rx_irq = irqres[1].start;
740 ltq_port->err_irq = irqres[2].start;
741
742 lqasc_port[line] = ltq_port;
743 platform_set_drvdata(pdev, ltq_port);
744
745 ret = uart_add_one_port(&lqasc_reg, port);
746
747 return ret;
748}
749
750static const struct of_device_id ltq_asc_match[] = {
751 { .compatible = DRVNAME },
752 {},
753};
754
755static struct platform_driver lqasc_driver = {
756 .driver = {
757 .name = DRVNAME,
758 .of_match_table = ltq_asc_match,
759 },
760};
761
762int __init
763init_lqasc(void)
764{
765 int ret;
766
767 ret = uart_register_driver(&lqasc_reg);
768 if (ret != 0)
769 return ret;
770
771 ret = platform_driver_probe(&lqasc_driver, lqasc_probe);
772 if (ret != 0)
773 uart_unregister_driver(&lqasc_reg);
774
775 return ret;
776}
777device_initcall(init_lqasc);
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Based on drivers/char/serial.c, by Linus Torvalds, Theodore Ts'o.
4 *
5 * Copyright (C) 2004 Infineon IFAP DC COM CPE
6 * Copyright (C) 2007 Felix Fietkau <nbd@openwrt.org>
7 * Copyright (C) 2007 John Crispin <john@phrozen.org>
8 * Copyright (C) 2010 Thomas Langer, <thomas.langer@lantiq.com>
9 */
10
11#include <linux/bitfield.h>
12#include <linux/clk.h>
13#include <linux/console.h>
14#include <linux/device.h>
15#include <linux/init.h>
16#include <linux/io.h>
17#include <linux/ioport.h>
18#include <linux/lantiq.h>
19#include <linux/module.h>
20#include <linux/of_platform.h>
21#include <linux/serial.h>
22#include <linux/serial_core.h>
23#include <linux/slab.h>
24#include <linux/sysrq.h>
25#include <linux/tty.h>
26#include <linux/tty_flip.h>
27
28#define PORT_LTQ_ASC 111
29#define MAXPORTS 2
30#define UART_DUMMY_UER_RX 1
31#define DRVNAME "lantiq,asc"
32#ifdef __BIG_ENDIAN
33#define LTQ_ASC_TBUF (0x0020 + 3)
34#define LTQ_ASC_RBUF (0x0024 + 3)
35#else
36#define LTQ_ASC_TBUF 0x0020
37#define LTQ_ASC_RBUF 0x0024
38#endif
39#define LTQ_ASC_FSTAT 0x0048
40#define LTQ_ASC_WHBSTATE 0x0018
41#define LTQ_ASC_STATE 0x0014
42#define LTQ_ASC_IRNCR 0x00F8
43#define LTQ_ASC_CLC 0x0000
44#define LTQ_ASC_ID 0x0008
45#define LTQ_ASC_PISEL 0x0004
46#define LTQ_ASC_TXFCON 0x0044
47#define LTQ_ASC_RXFCON 0x0040
48#define LTQ_ASC_CON 0x0010
49#define LTQ_ASC_BG 0x0050
50#define LTQ_ASC_IRNREN 0x00F4
51
52#define ASC_IRNREN_TX 0x1
53#define ASC_IRNREN_RX 0x2
54#define ASC_IRNREN_ERR 0x4
55#define ASC_IRNREN_TX_BUF 0x8
56#define ASC_IRNCR_TIR 0x1
57#define ASC_IRNCR_RIR 0x2
58#define ASC_IRNCR_EIR 0x4
59#define ASC_IRNCR_MASK GENMASK(2, 0)
60
61#define ASCOPT_CSIZE 0x3
62#define TXFIFO_FL 1
63#define RXFIFO_FL 1
64#define ASCCLC_DISS 0x2
65#define ASCCLC_RMCMASK 0x0000FF00
66#define ASCCLC_RMCOFFSET 8
67#define ASCCON_M_8ASYNC 0x0
68#define ASCCON_M_7ASYNC 0x2
69#define ASCCON_ODD 0x00000020
70#define ASCCON_STP 0x00000080
71#define ASCCON_BRS 0x00000100
72#define ASCCON_FDE 0x00000200
73#define ASCCON_R 0x00008000
74#define ASCCON_FEN 0x00020000
75#define ASCCON_ROEN 0x00080000
76#define ASCCON_TOEN 0x00100000
77#define ASCSTATE_PE 0x00010000
78#define ASCSTATE_FE 0x00020000
79#define ASCSTATE_ROE 0x00080000
80#define ASCSTATE_ANY (ASCSTATE_ROE|ASCSTATE_PE|ASCSTATE_FE)
81#define ASCWHBSTATE_CLRREN 0x00000001
82#define ASCWHBSTATE_SETREN 0x00000002
83#define ASCWHBSTATE_CLRPE 0x00000004
84#define ASCWHBSTATE_CLRFE 0x00000008
85#define ASCWHBSTATE_CLRROE 0x00000020
86#define ASCTXFCON_TXFEN 0x0001
87#define ASCTXFCON_TXFFLU 0x0002
88#define ASCTXFCON_TXFITLMASK 0x3F00
89#define ASCTXFCON_TXFITLOFF 8
90#define ASCRXFCON_RXFEN 0x0001
91#define ASCRXFCON_RXFFLU 0x0002
92#define ASCRXFCON_RXFITLMASK 0x3F00
93#define ASCRXFCON_RXFITLOFF 8
94#define ASCFSTAT_RXFFLMASK 0x003F
95#define ASCFSTAT_TXFFLMASK 0x3F00
96#define ASCFSTAT_TXFREEMASK 0x3F000000
97
98static struct ltq_uart_port *lqasc_port[MAXPORTS];
99static struct uart_driver lqasc_reg;
100
101struct ltq_soc_data {
102 int (*fetch_irq)(struct device *dev, struct ltq_uart_port *ltq_port);
103 int (*request_irq)(struct uart_port *port);
104 void (*free_irq)(struct uart_port *port);
105};
106
107struct ltq_uart_port {
108 struct uart_port port;
109 /* clock used to derive divider */
110 struct clk *freqclk;
111 /* clock gating of the ASC core */
112 struct clk *clk;
113 unsigned int tx_irq;
114 unsigned int rx_irq;
115 unsigned int err_irq;
116 unsigned int common_irq;
117 spinlock_t lock; /* exclusive access for multi core */
118
119 const struct ltq_soc_data *soc;
120};
121
122static inline void asc_update_bits(u32 clear, u32 set, void __iomem *reg)
123{
124 u32 tmp = __raw_readl(reg);
125
126 __raw_writel((tmp & ~clear) | set, reg);
127}
128
129static inline struct
130ltq_uart_port *to_ltq_uart_port(struct uart_port *port)
131{
132 return container_of(port, struct ltq_uart_port, port);
133}
134
135static void
136lqasc_stop_tx(struct uart_port *port)
137{
138 return;
139}
140
141static bool lqasc_tx_ready(struct uart_port *port)
142{
143 u32 fstat = __raw_readl(port->membase + LTQ_ASC_FSTAT);
144
145 return FIELD_GET(ASCFSTAT_TXFREEMASK, fstat);
146}
147
148static void
149lqasc_start_tx(struct uart_port *port)
150{
151 unsigned long flags;
152 struct ltq_uart_port *ltq_port = to_ltq_uart_port(port);
153 u8 ch;
154
155 spin_lock_irqsave(<q_port->lock, flags);
156 uart_port_tx(port, ch,
157 lqasc_tx_ready(port),
158 writeb(ch, port->membase + LTQ_ASC_TBUF));
159 spin_unlock_irqrestore(<q_port->lock, flags);
160 return;
161}
162
163static void
164lqasc_stop_rx(struct uart_port *port)
165{
166 __raw_writel(ASCWHBSTATE_CLRREN, port->membase + LTQ_ASC_WHBSTATE);
167}
168
169static int
170lqasc_rx_chars(struct uart_port *port)
171{
172 struct tty_port *tport = &port->state->port;
173 unsigned int ch = 0, rsr = 0, fifocnt;
174
175 fifocnt = __raw_readl(port->membase + LTQ_ASC_FSTAT) &
176 ASCFSTAT_RXFFLMASK;
177 while (fifocnt--) {
178 u8 flag = TTY_NORMAL;
179 ch = readb(port->membase + LTQ_ASC_RBUF);
180 rsr = (__raw_readl(port->membase + LTQ_ASC_STATE)
181 & ASCSTATE_ANY) | UART_DUMMY_UER_RX;
182 tty_flip_buffer_push(tport);
183 port->icount.rx++;
184
185 /*
186 * Note that the error handling code is
187 * out of the main execution path
188 */
189 if (rsr & ASCSTATE_ANY) {
190 if (rsr & ASCSTATE_PE) {
191 port->icount.parity++;
192 asc_update_bits(0, ASCWHBSTATE_CLRPE,
193 port->membase + LTQ_ASC_WHBSTATE);
194 } else if (rsr & ASCSTATE_FE) {
195 port->icount.frame++;
196 asc_update_bits(0, ASCWHBSTATE_CLRFE,
197 port->membase + LTQ_ASC_WHBSTATE);
198 }
199 if (rsr & ASCSTATE_ROE) {
200 port->icount.overrun++;
201 asc_update_bits(0, ASCWHBSTATE_CLRROE,
202 port->membase + LTQ_ASC_WHBSTATE);
203 }
204
205 rsr &= port->read_status_mask;
206
207 if (rsr & ASCSTATE_PE)
208 flag = TTY_PARITY;
209 else if (rsr & ASCSTATE_FE)
210 flag = TTY_FRAME;
211 }
212
213 if ((rsr & port->ignore_status_mask) == 0)
214 tty_insert_flip_char(tport, ch, flag);
215
216 if (rsr & ASCSTATE_ROE)
217 /*
218 * Overrun is special, since it's reported
219 * immediately, and doesn't affect the current
220 * character
221 */
222 tty_insert_flip_char(tport, 0, TTY_OVERRUN);
223 }
224
225 if (ch != 0)
226 tty_flip_buffer_push(tport);
227
228 return 0;
229}
230
231static irqreturn_t
232lqasc_tx_int(int irq, void *_port)
233{
234 unsigned long flags;
235 struct uart_port *port = (struct uart_port *)_port;
236 struct ltq_uart_port *ltq_port = to_ltq_uart_port(port);
237
238 spin_lock_irqsave(<q_port->lock, flags);
239 __raw_writel(ASC_IRNCR_TIR, port->membase + LTQ_ASC_IRNCR);
240 spin_unlock_irqrestore(<q_port->lock, flags);
241 lqasc_start_tx(port);
242 return IRQ_HANDLED;
243}
244
245static irqreturn_t
246lqasc_err_int(int irq, void *_port)
247{
248 unsigned long flags;
249 struct uart_port *port = (struct uart_port *)_port;
250 struct ltq_uart_port *ltq_port = to_ltq_uart_port(port);
251
252 spin_lock_irqsave(<q_port->lock, flags);
253 /* clear any pending interrupts */
254 asc_update_bits(0, ASCWHBSTATE_CLRPE | ASCWHBSTATE_CLRFE |
255 ASCWHBSTATE_CLRROE, port->membase + LTQ_ASC_WHBSTATE);
256 spin_unlock_irqrestore(<q_port->lock, flags);
257 return IRQ_HANDLED;
258}
259
260static irqreturn_t
261lqasc_rx_int(int irq, void *_port)
262{
263 unsigned long flags;
264 struct uart_port *port = (struct uart_port *)_port;
265 struct ltq_uart_port *ltq_port = to_ltq_uart_port(port);
266
267 spin_lock_irqsave(<q_port->lock, flags);
268 __raw_writel(ASC_IRNCR_RIR, port->membase + LTQ_ASC_IRNCR);
269 lqasc_rx_chars(port);
270 spin_unlock_irqrestore(<q_port->lock, flags);
271 return IRQ_HANDLED;
272}
273
274static irqreturn_t lqasc_irq(int irq, void *p)
275{
276 unsigned long flags;
277 u32 stat;
278 struct uart_port *port = p;
279 struct ltq_uart_port *ltq_port = to_ltq_uart_port(port);
280
281 spin_lock_irqsave(<q_port->lock, flags);
282 stat = readl(port->membase + LTQ_ASC_IRNCR);
283 spin_unlock_irqrestore(<q_port->lock, flags);
284 if (!(stat & ASC_IRNCR_MASK))
285 return IRQ_NONE;
286
287 if (stat & ASC_IRNCR_TIR)
288 lqasc_tx_int(irq, p);
289
290 if (stat & ASC_IRNCR_RIR)
291 lqasc_rx_int(irq, p);
292
293 if (stat & ASC_IRNCR_EIR)
294 lqasc_err_int(irq, p);
295
296 return IRQ_HANDLED;
297}
298
299static unsigned int
300lqasc_tx_empty(struct uart_port *port)
301{
302 int status;
303 status = __raw_readl(port->membase + LTQ_ASC_FSTAT) &
304 ASCFSTAT_TXFFLMASK;
305 return status ? 0 : TIOCSER_TEMT;
306}
307
308static unsigned int
309lqasc_get_mctrl(struct uart_port *port)
310{
311 return TIOCM_CTS | TIOCM_CAR | TIOCM_DSR;
312}
313
314static void
315lqasc_set_mctrl(struct uart_port *port, u_int mctrl)
316{
317}
318
319static void
320lqasc_break_ctl(struct uart_port *port, int break_state)
321{
322}
323
324static int
325lqasc_startup(struct uart_port *port)
326{
327 struct ltq_uart_port *ltq_port = to_ltq_uart_port(port);
328 int retval;
329 unsigned long flags;
330
331 if (!IS_ERR(ltq_port->clk))
332 clk_prepare_enable(ltq_port->clk);
333 port->uartclk = clk_get_rate(ltq_port->freqclk);
334
335 spin_lock_irqsave(<q_port->lock, flags);
336 asc_update_bits(ASCCLC_DISS | ASCCLC_RMCMASK, (1 << ASCCLC_RMCOFFSET),
337 port->membase + LTQ_ASC_CLC);
338
339 __raw_writel(0, port->membase + LTQ_ASC_PISEL);
340 __raw_writel(
341 ((TXFIFO_FL << ASCTXFCON_TXFITLOFF) & ASCTXFCON_TXFITLMASK) |
342 ASCTXFCON_TXFEN | ASCTXFCON_TXFFLU,
343 port->membase + LTQ_ASC_TXFCON);
344 __raw_writel(
345 ((RXFIFO_FL << ASCRXFCON_RXFITLOFF) & ASCRXFCON_RXFITLMASK)
346 | ASCRXFCON_RXFEN | ASCRXFCON_RXFFLU,
347 port->membase + LTQ_ASC_RXFCON);
348 /* make sure other settings are written to hardware before
349 * setting enable bits
350 */
351 wmb();
352 asc_update_bits(0, ASCCON_M_8ASYNC | ASCCON_FEN | ASCCON_TOEN |
353 ASCCON_ROEN, port->membase + LTQ_ASC_CON);
354
355 spin_unlock_irqrestore(<q_port->lock, flags);
356
357 retval = ltq_port->soc->request_irq(port);
358 if (retval)
359 return retval;
360
361 __raw_writel(ASC_IRNREN_RX | ASC_IRNREN_ERR | ASC_IRNREN_TX,
362 port->membase + LTQ_ASC_IRNREN);
363 return retval;
364}
365
366static void
367lqasc_shutdown(struct uart_port *port)
368{
369 struct ltq_uart_port *ltq_port = to_ltq_uart_port(port);
370 unsigned long flags;
371
372 ltq_port->soc->free_irq(port);
373
374 spin_lock_irqsave(<q_port->lock, flags);
375 __raw_writel(0, port->membase + LTQ_ASC_CON);
376 asc_update_bits(ASCRXFCON_RXFEN, ASCRXFCON_RXFFLU,
377 port->membase + LTQ_ASC_RXFCON);
378 asc_update_bits(ASCTXFCON_TXFEN, ASCTXFCON_TXFFLU,
379 port->membase + LTQ_ASC_TXFCON);
380 spin_unlock_irqrestore(<q_port->lock, flags);
381 if (!IS_ERR(ltq_port->clk))
382 clk_disable_unprepare(ltq_port->clk);
383}
384
385static void
386lqasc_set_termios(struct uart_port *port, struct ktermios *new,
387 const struct ktermios *old)
388{
389 unsigned int cflag;
390 unsigned int iflag;
391 unsigned int divisor;
392 unsigned int baud;
393 unsigned int con = 0;
394 unsigned long flags;
395 struct ltq_uart_port *ltq_port = to_ltq_uart_port(port);
396
397 cflag = new->c_cflag;
398 iflag = new->c_iflag;
399
400 switch (cflag & CSIZE) {
401 case CS7:
402 con = ASCCON_M_7ASYNC;
403 break;
404
405 case CS5:
406 case CS6:
407 default:
408 new->c_cflag &= ~ CSIZE;
409 new->c_cflag |= CS8;
410 con = ASCCON_M_8ASYNC;
411 break;
412 }
413
414 cflag &= ~CMSPAR; /* Mark/Space parity is not supported */
415
416 if (cflag & CSTOPB)
417 con |= ASCCON_STP;
418
419 if (cflag & PARENB) {
420 if (!(cflag & PARODD))
421 con &= ~ASCCON_ODD;
422 else
423 con |= ASCCON_ODD;
424 }
425
426 port->read_status_mask = ASCSTATE_ROE;
427 if (iflag & INPCK)
428 port->read_status_mask |= ASCSTATE_FE | ASCSTATE_PE;
429
430 port->ignore_status_mask = 0;
431 if (iflag & IGNPAR)
432 port->ignore_status_mask |= ASCSTATE_FE | ASCSTATE_PE;
433
434 if (iflag & IGNBRK) {
435 /*
436 * If we're ignoring parity and break indicators,
437 * ignore overruns too (for real raw support).
438 */
439 if (iflag & IGNPAR)
440 port->ignore_status_mask |= ASCSTATE_ROE;
441 }
442
443 if ((cflag & CREAD) == 0)
444 port->ignore_status_mask |= UART_DUMMY_UER_RX;
445
446 /* set error signals - framing, parity and overrun, enable receiver */
447 con |= ASCCON_FEN | ASCCON_TOEN | ASCCON_ROEN;
448
449 spin_lock_irqsave(<q_port->lock, flags);
450
451 /* set up CON */
452 asc_update_bits(0, con, port->membase + LTQ_ASC_CON);
453
454 /* Set baud rate - take a divider of 2 into account */
455 baud = uart_get_baud_rate(port, new, old, 0, port->uartclk / 16);
456 divisor = uart_get_divisor(port, baud);
457 divisor = divisor / 2 - 1;
458
459 /* disable the baudrate generator */
460 asc_update_bits(ASCCON_R, 0, port->membase + LTQ_ASC_CON);
461
462 /* make sure the fractional divider is off */
463 asc_update_bits(ASCCON_FDE, 0, port->membase + LTQ_ASC_CON);
464
465 /* set up to use divisor of 2 */
466 asc_update_bits(ASCCON_BRS, 0, port->membase + LTQ_ASC_CON);
467
468 /* now we can write the new baudrate into the register */
469 __raw_writel(divisor, port->membase + LTQ_ASC_BG);
470
471 /* turn the baudrate generator back on */
472 asc_update_bits(0, ASCCON_R, port->membase + LTQ_ASC_CON);
473
474 /* enable rx */
475 __raw_writel(ASCWHBSTATE_SETREN, port->membase + LTQ_ASC_WHBSTATE);
476
477 spin_unlock_irqrestore(<q_port->lock, flags);
478
479 /* Don't rewrite B0 */
480 if (tty_termios_baud_rate(new))
481 tty_termios_encode_baud_rate(new, baud, baud);
482
483 uart_update_timeout(port, cflag, baud);
484}
485
486static const char*
487lqasc_type(struct uart_port *port)
488{
489 if (port->type == PORT_LTQ_ASC)
490 return DRVNAME;
491 else
492 return NULL;
493}
494
495static void
496lqasc_release_port(struct uart_port *port)
497{
498 struct platform_device *pdev = to_platform_device(port->dev);
499
500 if (port->flags & UPF_IOREMAP) {
501 devm_iounmap(&pdev->dev, port->membase);
502 port->membase = NULL;
503 }
504}
505
506static int
507lqasc_request_port(struct uart_port *port)
508{
509 struct platform_device *pdev = to_platform_device(port->dev);
510 struct resource *res;
511 int size;
512
513 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
514 if (!res) {
515 dev_err(&pdev->dev, "cannot obtain I/O memory region");
516 return -ENODEV;
517 }
518 size = resource_size(res);
519
520 res = devm_request_mem_region(&pdev->dev, res->start,
521 size, dev_name(&pdev->dev));
522 if (!res) {
523 dev_err(&pdev->dev, "cannot request I/O memory region");
524 return -EBUSY;
525 }
526
527 if (port->flags & UPF_IOREMAP) {
528 port->membase = devm_ioremap(&pdev->dev,
529 port->mapbase, size);
530 if (port->membase == NULL)
531 return -ENOMEM;
532 }
533 return 0;
534}
535
536static void
537lqasc_config_port(struct uart_port *port, int flags)
538{
539 if (flags & UART_CONFIG_TYPE) {
540 port->type = PORT_LTQ_ASC;
541 lqasc_request_port(port);
542 }
543}
544
545static int
546lqasc_verify_port(struct uart_port *port,
547 struct serial_struct *ser)
548{
549 int ret = 0;
550 if (ser->type != PORT_UNKNOWN && ser->type != PORT_LTQ_ASC)
551 ret = -EINVAL;
552 if (ser->irq < 0 || ser->irq >= NR_IRQS)
553 ret = -EINVAL;
554 if (ser->baud_base < 9600)
555 ret = -EINVAL;
556 return ret;
557}
558
559static const struct uart_ops lqasc_pops = {
560 .tx_empty = lqasc_tx_empty,
561 .set_mctrl = lqasc_set_mctrl,
562 .get_mctrl = lqasc_get_mctrl,
563 .stop_tx = lqasc_stop_tx,
564 .start_tx = lqasc_start_tx,
565 .stop_rx = lqasc_stop_rx,
566 .break_ctl = lqasc_break_ctl,
567 .startup = lqasc_startup,
568 .shutdown = lqasc_shutdown,
569 .set_termios = lqasc_set_termios,
570 .type = lqasc_type,
571 .release_port = lqasc_release_port,
572 .request_port = lqasc_request_port,
573 .config_port = lqasc_config_port,
574 .verify_port = lqasc_verify_port,
575};
576
577#ifdef CONFIG_SERIAL_LANTIQ_CONSOLE
578static void
579lqasc_console_putchar(struct uart_port *port, unsigned char ch)
580{
581 if (!port->membase)
582 return;
583
584 while (!lqasc_tx_ready(port))
585 ;
586
587 writeb(ch, port->membase + LTQ_ASC_TBUF);
588}
589
590static void lqasc_serial_port_write(struct uart_port *port, const char *s,
591 u_int count)
592{
593 uart_console_write(port, s, count, lqasc_console_putchar);
594}
595
596static void
597lqasc_console_write(struct console *co, const char *s, u_int count)
598{
599 struct ltq_uart_port *ltq_port;
600 unsigned long flags;
601
602 if (co->index >= MAXPORTS)
603 return;
604
605 ltq_port = lqasc_port[co->index];
606 if (!ltq_port)
607 return;
608
609 spin_lock_irqsave(<q_port->lock, flags);
610 lqasc_serial_port_write(<q_port->port, s, count);
611 spin_unlock_irqrestore(<q_port->lock, flags);
612}
613
614static int __init
615lqasc_console_setup(struct console *co, char *options)
616{
617 struct ltq_uart_port *ltq_port;
618 struct uart_port *port;
619 int baud = 115200;
620 int bits = 8;
621 int parity = 'n';
622 int flow = 'n';
623
624 if (co->index >= MAXPORTS)
625 return -ENODEV;
626
627 ltq_port = lqasc_port[co->index];
628 if (!ltq_port)
629 return -ENODEV;
630
631 port = <q_port->port;
632
633 if (!IS_ERR(ltq_port->clk))
634 clk_prepare_enable(ltq_port->clk);
635
636 port->uartclk = clk_get_rate(ltq_port->freqclk);
637
638 if (options)
639 uart_parse_options(options, &baud, &parity, &bits, &flow);
640 return uart_set_options(port, co, baud, parity, bits, flow);
641}
642
643static struct console lqasc_console = {
644 .name = "ttyLTQ",
645 .write = lqasc_console_write,
646 .device = uart_console_device,
647 .setup = lqasc_console_setup,
648 .flags = CON_PRINTBUFFER,
649 .index = -1,
650 .data = &lqasc_reg,
651};
652
653static int __init
654lqasc_console_init(void)
655{
656 register_console(&lqasc_console);
657 return 0;
658}
659console_initcall(lqasc_console_init);
660
661static void lqasc_serial_early_console_write(struct console *co,
662 const char *s,
663 u_int count)
664{
665 struct earlycon_device *dev = co->data;
666
667 lqasc_serial_port_write(&dev->port, s, count);
668}
669
670static int __init
671lqasc_serial_early_console_setup(struct earlycon_device *device,
672 const char *opt)
673{
674 if (!device->port.membase)
675 return -ENODEV;
676
677 device->con->write = lqasc_serial_early_console_write;
678 return 0;
679}
680OF_EARLYCON_DECLARE(lantiq, "lantiq,asc", lqasc_serial_early_console_setup);
681OF_EARLYCON_DECLARE(lantiq, "intel,lgm-asc", lqasc_serial_early_console_setup);
682
683#define LANTIQ_SERIAL_CONSOLE (&lqasc_console)
684
685#else
686
687#define LANTIQ_SERIAL_CONSOLE NULL
688
689#endif /* CONFIG_SERIAL_LANTIQ_CONSOLE */
690
691static struct uart_driver lqasc_reg = {
692 .owner = THIS_MODULE,
693 .driver_name = DRVNAME,
694 .dev_name = "ttyLTQ",
695 .major = 0,
696 .minor = 0,
697 .nr = MAXPORTS,
698 .cons = LANTIQ_SERIAL_CONSOLE,
699};
700
701static int fetch_irq_lantiq(struct device *dev, struct ltq_uart_port *ltq_port)
702{
703 struct uart_port *port = <q_port->port;
704 struct platform_device *pdev = to_platform_device(dev);
705 int irq;
706
707 irq = platform_get_irq(pdev, 0);
708 if (irq < 0)
709 return irq;
710 ltq_port->tx_irq = irq;
711 irq = platform_get_irq(pdev, 1);
712 if (irq < 0)
713 return irq;
714 ltq_port->rx_irq = irq;
715 irq = platform_get_irq(pdev, 2);
716 if (irq < 0)
717 return irq;
718 ltq_port->err_irq = irq;
719
720 port->irq = ltq_port->tx_irq;
721
722 return 0;
723}
724
725static int request_irq_lantiq(struct uart_port *port)
726{
727 struct ltq_uart_port *ltq_port = to_ltq_uart_port(port);
728 int retval;
729
730 retval = request_irq(ltq_port->tx_irq, lqasc_tx_int,
731 0, "asc_tx", port);
732 if (retval) {
733 dev_err(port->dev, "failed to request asc_tx\n");
734 return retval;
735 }
736
737 retval = request_irq(ltq_port->rx_irq, lqasc_rx_int,
738 0, "asc_rx", port);
739 if (retval) {
740 dev_err(port->dev, "failed to request asc_rx\n");
741 goto err1;
742 }
743
744 retval = request_irq(ltq_port->err_irq, lqasc_err_int,
745 0, "asc_err", port);
746 if (retval) {
747 dev_err(port->dev, "failed to request asc_err\n");
748 goto err2;
749 }
750 return 0;
751
752err2:
753 free_irq(ltq_port->rx_irq, port);
754err1:
755 free_irq(ltq_port->tx_irq, port);
756 return retval;
757}
758
759static void free_irq_lantiq(struct uart_port *port)
760{
761 struct ltq_uart_port *ltq_port = to_ltq_uart_port(port);
762
763 free_irq(ltq_port->tx_irq, port);
764 free_irq(ltq_port->rx_irq, port);
765 free_irq(ltq_port->err_irq, port);
766}
767
768static int fetch_irq_intel(struct device *dev, struct ltq_uart_port *ltq_port)
769{
770 struct uart_port *port = <q_port->port;
771 int ret;
772
773 ret = platform_get_irq(to_platform_device(dev), 0);
774 if (ret < 0) {
775 dev_err(dev, "failed to fetch IRQ for serial port\n");
776 return ret;
777 }
778 ltq_port->common_irq = ret;
779 port->irq = ret;
780
781 return 0;
782}
783
784static int request_irq_intel(struct uart_port *port)
785{
786 struct ltq_uart_port *ltq_port = to_ltq_uart_port(port);
787 int retval;
788
789 retval = request_irq(ltq_port->common_irq, lqasc_irq, 0,
790 "asc_irq", port);
791 if (retval)
792 dev_err(port->dev, "failed to request asc_irq\n");
793
794 return retval;
795}
796
797static void free_irq_intel(struct uart_port *port)
798{
799 struct ltq_uart_port *ltq_port = to_ltq_uart_port(port);
800
801 free_irq(ltq_port->common_irq, port);
802}
803
804static int lqasc_probe(struct platform_device *pdev)
805{
806 struct device_node *node = pdev->dev.of_node;
807 struct ltq_uart_port *ltq_port;
808 struct uart_port *port;
809 struct resource *mmres;
810 int line;
811 int ret;
812
813 mmres = platform_get_resource(pdev, IORESOURCE_MEM, 0);
814 if (!mmres) {
815 dev_err(&pdev->dev,
816 "failed to get memory for serial port\n");
817 return -ENODEV;
818 }
819
820 ltq_port = devm_kzalloc(&pdev->dev, sizeof(struct ltq_uart_port),
821 GFP_KERNEL);
822 if (!ltq_port)
823 return -ENOMEM;
824
825 port = <q_port->port;
826
827 ltq_port->soc = of_device_get_match_data(&pdev->dev);
828 ret = ltq_port->soc->fetch_irq(&pdev->dev, ltq_port);
829 if (ret)
830 return ret;
831
832 /* get serial id */
833 line = of_alias_get_id(node, "serial");
834 if (line < 0) {
835 if (IS_ENABLED(CONFIG_LANTIQ)) {
836 if (mmres->start == CPHYSADDR(LTQ_EARLY_ASC))
837 line = 0;
838 else
839 line = 1;
840 } else {
841 dev_err(&pdev->dev, "failed to get alias id, errno %d\n",
842 line);
843 return line;
844 }
845 }
846
847 if (lqasc_port[line]) {
848 dev_err(&pdev->dev, "port %d already allocated\n", line);
849 return -EBUSY;
850 }
851
852 port->iotype = SERIAL_IO_MEM;
853 port->flags = UPF_BOOT_AUTOCONF | UPF_IOREMAP;
854 port->ops = &lqasc_pops;
855 port->fifosize = 16;
856 port->type = PORT_LTQ_ASC;
857 port->line = line;
858 port->dev = &pdev->dev;
859 /* unused, just to be backward-compatible */
860 port->mapbase = mmres->start;
861
862 if (IS_ENABLED(CONFIG_LANTIQ) && !IS_ENABLED(CONFIG_COMMON_CLK))
863 ltq_port->freqclk = clk_get_fpi();
864 else
865 ltq_port->freqclk = devm_clk_get(&pdev->dev, "freq");
866
867
868 if (IS_ERR(ltq_port->freqclk)) {
869 pr_err("failed to get fpi clk\n");
870 return -ENOENT;
871 }
872
873 /* not all asc ports have clock gates, lets ignore the return code */
874 if (IS_ENABLED(CONFIG_LANTIQ) && !IS_ENABLED(CONFIG_COMMON_CLK))
875 ltq_port->clk = clk_get(&pdev->dev, NULL);
876 else
877 ltq_port->clk = devm_clk_get(&pdev->dev, "asc");
878
879 spin_lock_init(<q_port->lock);
880 lqasc_port[line] = ltq_port;
881 platform_set_drvdata(pdev, ltq_port);
882
883 ret = uart_add_one_port(&lqasc_reg, port);
884
885 return ret;
886}
887
888static int lqasc_remove(struct platform_device *pdev)
889{
890 struct uart_port *port = platform_get_drvdata(pdev);
891
892 return uart_remove_one_port(&lqasc_reg, port);
893}
894
895static const struct ltq_soc_data soc_data_lantiq = {
896 .fetch_irq = fetch_irq_lantiq,
897 .request_irq = request_irq_lantiq,
898 .free_irq = free_irq_lantiq,
899};
900
901static const struct ltq_soc_data soc_data_intel = {
902 .fetch_irq = fetch_irq_intel,
903 .request_irq = request_irq_intel,
904 .free_irq = free_irq_intel,
905};
906
907static const struct of_device_id ltq_asc_match[] = {
908 { .compatible = "lantiq,asc", .data = &soc_data_lantiq },
909 { .compatible = "intel,lgm-asc", .data = &soc_data_intel },
910 {},
911};
912MODULE_DEVICE_TABLE(of, ltq_asc_match);
913
914static struct platform_driver lqasc_driver = {
915 .probe = lqasc_probe,
916 .remove = lqasc_remove,
917 .driver = {
918 .name = DRVNAME,
919 .of_match_table = ltq_asc_match,
920 },
921};
922
923static int __init
924init_lqasc(void)
925{
926 int ret;
927
928 ret = uart_register_driver(&lqasc_reg);
929 if (ret != 0)
930 return ret;
931
932 ret = platform_driver_register(&lqasc_driver);
933 if (ret != 0)
934 uart_unregister_driver(&lqasc_reg);
935
936 return ret;
937}
938
939static void __exit exit_lqasc(void)
940{
941 platform_driver_unregister(&lqasc_driver);
942 uart_unregister_driver(&lqasc_reg);
943}
944
945module_init(init_lqasc);
946module_exit(exit_lqasc);
947
948MODULE_DESCRIPTION("Serial driver for Lantiq & Intel gateway SoCs");
949MODULE_LICENSE("GPL v2");