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.h>
21#include <linux/platform_device.h>
22#include <linux/serial.h>
23#include <linux/serial_core.h>
24#include <linux/slab.h>
25#include <linux/sysrq.h>
26#include <linux/tty.h>
27#include <linux/tty_flip.h>
28
29#define PORT_LTQ_ASC 111
30#define MAXPORTS 2
31#define UART_DUMMY_UER_RX 1
32#define DRVNAME "lantiq,asc"
33#ifdef __BIG_ENDIAN
34#define LTQ_ASC_TBUF (0x0020 + 3)
35#define LTQ_ASC_RBUF (0x0024 + 3)
36#else
37#define LTQ_ASC_TBUF 0x0020
38#define LTQ_ASC_RBUF 0x0024
39#endif
40#define LTQ_ASC_FSTAT 0x0048
41#define LTQ_ASC_WHBSTATE 0x0018
42#define LTQ_ASC_STATE 0x0014
43#define LTQ_ASC_IRNCR 0x00F8
44#define LTQ_ASC_CLC 0x0000
45#define LTQ_ASC_ID 0x0008
46#define LTQ_ASC_PISEL 0x0004
47#define LTQ_ASC_TXFCON 0x0044
48#define LTQ_ASC_RXFCON 0x0040
49#define LTQ_ASC_CON 0x0010
50#define LTQ_ASC_BG 0x0050
51#define LTQ_ASC_IRNREN 0x00F4
52
53#define ASC_IRNREN_TX 0x1
54#define ASC_IRNREN_RX 0x2
55#define ASC_IRNREN_ERR 0x4
56#define ASC_IRNREN_TX_BUF 0x8
57#define ASC_IRNCR_TIR 0x1
58#define ASC_IRNCR_RIR 0x2
59#define ASC_IRNCR_EIR 0x4
60#define ASC_IRNCR_MASK GENMASK(2, 0)
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
99static struct ltq_uart_port *lqasc_port[MAXPORTS];
100static struct uart_driver lqasc_reg;
101
102struct ltq_soc_data {
103 int (*fetch_irq)(struct device *dev, struct ltq_uart_port *ltq_port);
104 int (*request_irq)(struct uart_port *port);
105 void (*free_irq)(struct uart_port *port);
106};
107
108struct ltq_uart_port {
109 struct uart_port port;
110 /* clock used to derive divider */
111 struct clk *freqclk;
112 /* clock gating of the ASC core */
113 struct clk *clk;
114 unsigned int tx_irq;
115 unsigned int rx_irq;
116 unsigned int err_irq;
117 unsigned int common_irq;
118 spinlock_t lock; /* exclusive access for multi core */
119
120 const struct ltq_soc_data *soc;
121};
122
123static inline void asc_update_bits(u32 clear, u32 set, void __iomem *reg)
124{
125 u32 tmp = __raw_readl(addr: reg);
126
127 __raw_writel(val: (tmp & ~clear) | set, addr: reg);
128}
129
130static inline struct
131ltq_uart_port *to_ltq_uart_port(struct uart_port *port)
132{
133 return container_of(port, struct ltq_uart_port, port);
134}
135
136static void
137lqasc_stop_tx(struct uart_port *port)
138{
139 return;
140}
141
142static bool lqasc_tx_ready(struct uart_port *port)
143{
144 u32 fstat = __raw_readl(addr: port->membase + LTQ_ASC_FSTAT);
145
146 return FIELD_GET(ASCFSTAT_TXFREEMASK, fstat);
147}
148
149static void
150lqasc_start_tx(struct uart_port *port)
151{
152 unsigned long flags;
153 struct ltq_uart_port *ltq_port = to_ltq_uart_port(port);
154 u8 ch;
155
156 spin_lock_irqsave(&ltq_port->lock, flags);
157 uart_port_tx(port, ch,
158 lqasc_tx_ready(port),
159 writeb(ch, port->membase + LTQ_ASC_TBUF));
160 spin_unlock_irqrestore(lock: &ltq_port->lock, flags);
161 return;
162}
163
164static void
165lqasc_stop_rx(struct uart_port *port)
166{
167 __raw_writel(ASCWHBSTATE_CLRREN, addr: port->membase + LTQ_ASC_WHBSTATE);
168}
169
170static int
171lqasc_rx_chars(struct uart_port *port)
172{
173 struct tty_port *tport = &port->state->port;
174 unsigned int ch = 0, rsr = 0, fifocnt;
175
176 fifocnt = __raw_readl(addr: port->membase + LTQ_ASC_FSTAT) &
177 ASCFSTAT_RXFFLMASK;
178 while (fifocnt--) {
179 u8 flag = TTY_NORMAL;
180 ch = readb(addr: port->membase + LTQ_ASC_RBUF);
181 rsr = (__raw_readl(addr: port->membase + LTQ_ASC_STATE)
182 & ASCSTATE_ANY) | UART_DUMMY_UER_RX;
183 tty_flip_buffer_push(port: tport);
184 port->icount.rx++;
185
186 /*
187 * Note that the error handling code is
188 * out of the main execution path
189 */
190 if (rsr & ASCSTATE_ANY) {
191 if (rsr & ASCSTATE_PE) {
192 port->icount.parity++;
193 asc_update_bits(clear: 0, ASCWHBSTATE_CLRPE,
194 reg: port->membase + LTQ_ASC_WHBSTATE);
195 } else if (rsr & ASCSTATE_FE) {
196 port->icount.frame++;
197 asc_update_bits(clear: 0, ASCWHBSTATE_CLRFE,
198 reg: port->membase + LTQ_ASC_WHBSTATE);
199 }
200 if (rsr & ASCSTATE_ROE) {
201 port->icount.overrun++;
202 asc_update_bits(clear: 0, ASCWHBSTATE_CLRROE,
203 reg: port->membase + LTQ_ASC_WHBSTATE);
204 }
205
206 rsr &= port->read_status_mask;
207
208 if (rsr & ASCSTATE_PE)
209 flag = TTY_PARITY;
210 else if (rsr & ASCSTATE_FE)
211 flag = TTY_FRAME;
212 }
213
214 if ((rsr & port->ignore_status_mask) == 0)
215 tty_insert_flip_char(port: tport, ch, flag);
216
217 if (rsr & ASCSTATE_ROE)
218 /*
219 * Overrun is special, since it's reported
220 * immediately, and doesn't affect the current
221 * character
222 */
223 tty_insert_flip_char(port: tport, ch: 0, TTY_OVERRUN);
224 }
225
226 if (ch != 0)
227 tty_flip_buffer_push(port: tport);
228
229 return 0;
230}
231
232static irqreturn_t
233lqasc_tx_int(int irq, void *_port)
234{
235 unsigned long flags;
236 struct uart_port *port = (struct uart_port *)_port;
237 struct ltq_uart_port *ltq_port = to_ltq_uart_port(port);
238
239 spin_lock_irqsave(&ltq_port->lock, flags);
240 __raw_writel(ASC_IRNCR_TIR, addr: port->membase + LTQ_ASC_IRNCR);
241 spin_unlock_irqrestore(lock: &ltq_port->lock, flags);
242 lqasc_start_tx(port);
243 return IRQ_HANDLED;
244}
245
246static irqreturn_t
247lqasc_err_int(int irq, void *_port)
248{
249 unsigned long flags;
250 struct uart_port *port = (struct uart_port *)_port;
251 struct ltq_uart_port *ltq_port = to_ltq_uart_port(port);
252
253 spin_lock_irqsave(&ltq_port->lock, flags);
254 __raw_writel(ASC_IRNCR_EIR, addr: port->membase + LTQ_ASC_IRNCR);
255 /* clear any pending interrupts */
256 asc_update_bits(clear: 0, ASCWHBSTATE_CLRPE | ASCWHBSTATE_CLRFE |
257 ASCWHBSTATE_CLRROE, reg: port->membase + LTQ_ASC_WHBSTATE);
258 spin_unlock_irqrestore(lock: &ltq_port->lock, flags);
259 return IRQ_HANDLED;
260}
261
262static irqreturn_t
263lqasc_rx_int(int irq, void *_port)
264{
265 unsigned long flags;
266 struct uart_port *port = (struct uart_port *)_port;
267 struct ltq_uart_port *ltq_port = to_ltq_uart_port(port);
268
269 spin_lock_irqsave(&ltq_port->lock, flags);
270 __raw_writel(ASC_IRNCR_RIR, addr: port->membase + LTQ_ASC_IRNCR);
271 lqasc_rx_chars(port);
272 spin_unlock_irqrestore(lock: &ltq_port->lock, flags);
273 return IRQ_HANDLED;
274}
275
276static irqreturn_t lqasc_irq(int irq, void *p)
277{
278 unsigned long flags;
279 u32 stat;
280 struct uart_port *port = p;
281 struct ltq_uart_port *ltq_port = to_ltq_uart_port(port);
282
283 spin_lock_irqsave(&ltq_port->lock, flags);
284 stat = readl(addr: port->membase + LTQ_ASC_IRNCR);
285 spin_unlock_irqrestore(lock: &ltq_port->lock, flags);
286 if (!(stat & ASC_IRNCR_MASK))
287 return IRQ_NONE;
288
289 if (stat & ASC_IRNCR_TIR)
290 lqasc_tx_int(irq, port: p);
291
292 if (stat & ASC_IRNCR_RIR)
293 lqasc_rx_int(irq, port: p);
294
295 if (stat & ASC_IRNCR_EIR)
296 lqasc_err_int(irq, port: p);
297
298 return IRQ_HANDLED;
299}
300
301static unsigned int
302lqasc_tx_empty(struct uart_port *port)
303{
304 int status;
305 status = __raw_readl(addr: port->membase + LTQ_ASC_FSTAT) &
306 ASCFSTAT_TXFFLMASK;
307 return status ? 0 : TIOCSER_TEMT;
308}
309
310static unsigned int
311lqasc_get_mctrl(struct uart_port *port)
312{
313 return TIOCM_CTS | TIOCM_CAR | TIOCM_DSR;
314}
315
316static void
317lqasc_set_mctrl(struct uart_port *port, u_int mctrl)
318{
319}
320
321static void
322lqasc_break_ctl(struct uart_port *port, int break_state)
323{
324}
325
326static int
327lqasc_startup(struct uart_port *port)
328{
329 struct ltq_uart_port *ltq_port = to_ltq_uart_port(port);
330 int retval;
331 unsigned long flags;
332
333 if (!IS_ERR(ptr: ltq_port->clk))
334 clk_prepare_enable(clk: ltq_port->clk);
335 port->uartclk = clk_get_rate(clk: ltq_port->freqclk);
336
337 spin_lock_irqsave(&ltq_port->lock, flags);
338 asc_update_bits(ASCCLC_DISS | ASCCLC_RMCMASK, set: (1 << ASCCLC_RMCOFFSET),
339 reg: port->membase + LTQ_ASC_CLC);
340
341 __raw_writel(val: 0, addr: port->membase + LTQ_ASC_PISEL);
342 __raw_writel(
343 val: ((TXFIFO_FL << ASCTXFCON_TXFITLOFF) & ASCTXFCON_TXFITLMASK) |
344 ASCTXFCON_TXFEN | ASCTXFCON_TXFFLU,
345 addr: port->membase + LTQ_ASC_TXFCON);
346 __raw_writel(
347 val: ((RXFIFO_FL << ASCRXFCON_RXFITLOFF) & ASCRXFCON_RXFITLMASK)
348 | ASCRXFCON_RXFEN | ASCRXFCON_RXFFLU,
349 addr: port->membase + LTQ_ASC_RXFCON);
350 /* make sure other settings are written to hardware before
351 * setting enable bits
352 */
353 wmb();
354 asc_update_bits(clear: 0, ASCCON_M_8ASYNC | ASCCON_FEN | ASCCON_TOEN |
355 ASCCON_ROEN, reg: port->membase + LTQ_ASC_CON);
356
357 spin_unlock_irqrestore(lock: &ltq_port->lock, flags);
358
359 retval = ltq_port->soc->request_irq(port);
360 if (retval)
361 return retval;
362
363 __raw_writel(ASC_IRNREN_RX | ASC_IRNREN_ERR | ASC_IRNREN_TX,
364 addr: port->membase + LTQ_ASC_IRNREN);
365 return retval;
366}
367
368static void
369lqasc_shutdown(struct uart_port *port)
370{
371 struct ltq_uart_port *ltq_port = to_ltq_uart_port(port);
372 unsigned long flags;
373
374 ltq_port->soc->free_irq(port);
375
376 spin_lock_irqsave(&ltq_port->lock, flags);
377 __raw_writel(val: 0, addr: port->membase + LTQ_ASC_CON);
378 asc_update_bits(ASCRXFCON_RXFEN, ASCRXFCON_RXFFLU,
379 reg: port->membase + LTQ_ASC_RXFCON);
380 asc_update_bits(ASCTXFCON_TXFEN, ASCTXFCON_TXFFLU,
381 reg: port->membase + LTQ_ASC_TXFCON);
382 spin_unlock_irqrestore(lock: &ltq_port->lock, flags);
383 if (!IS_ERR(ptr: ltq_port->clk))
384 clk_disable_unprepare(clk: ltq_port->clk);
385}
386
387static void
388lqasc_set_termios(struct uart_port *port, struct ktermios *new,
389 const 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 struct ltq_uart_port *ltq_port = to_ltq_uart_port(port);
398
399 cflag = new->c_cflag;
400 iflag = new->c_iflag;
401
402 switch (cflag & CSIZE) {
403 case CS7:
404 con = ASCCON_M_7ASYNC;
405 break;
406
407 case CS5:
408 case CS6:
409 default:
410 new->c_cflag &= ~ CSIZE;
411 new->c_cflag |= CS8;
412 con = ASCCON_M_8ASYNC;
413 break;
414 }
415
416 cflag &= ~CMSPAR; /* Mark/Space parity is not supported */
417
418 if (cflag & CSTOPB)
419 con |= ASCCON_STP;
420
421 if (cflag & PARENB) {
422 if (!(cflag & PARODD))
423 con &= ~ASCCON_ODD;
424 else
425 con |= ASCCON_ODD;
426 }
427
428 port->read_status_mask = ASCSTATE_ROE;
429 if (iflag & INPCK)
430 port->read_status_mask |= ASCSTATE_FE | ASCSTATE_PE;
431
432 port->ignore_status_mask = 0;
433 if (iflag & IGNPAR)
434 port->ignore_status_mask |= ASCSTATE_FE | ASCSTATE_PE;
435
436 if (iflag & IGNBRK) {
437 /*
438 * If we're ignoring parity and break indicators,
439 * ignore overruns too (for real raw support).
440 */
441 if (iflag & IGNPAR)
442 port->ignore_status_mask |= ASCSTATE_ROE;
443 }
444
445 if ((cflag & CREAD) == 0)
446 port->ignore_status_mask |= UART_DUMMY_UER_RX;
447
448 /* set error signals - framing, parity and overrun, enable receiver */
449 con |= ASCCON_FEN | ASCCON_TOEN | ASCCON_ROEN;
450
451 spin_lock_irqsave(&ltq_port->lock, flags);
452
453 /* set up CON */
454 asc_update_bits(clear: 0, set: con, reg: port->membase + LTQ_ASC_CON);
455
456 /* Set baud rate - take a divider of 2 into account */
457 baud = uart_get_baud_rate(port, termios: new, old, min: 0, max: port->uartclk / 16);
458 divisor = uart_get_divisor(port, baud);
459 divisor = divisor / 2 - 1;
460
461 /* disable the baudrate generator */
462 asc_update_bits(ASCCON_R, set: 0, reg: port->membase + LTQ_ASC_CON);
463
464 /* make sure the fractional divider is off */
465 asc_update_bits(ASCCON_FDE, set: 0, reg: port->membase + LTQ_ASC_CON);
466
467 /* set up to use divisor of 2 */
468 asc_update_bits(ASCCON_BRS, set: 0, reg: port->membase + LTQ_ASC_CON);
469
470 /* now we can write the new baudrate into the register */
471 __raw_writel(val: divisor, addr: port->membase + LTQ_ASC_BG);
472
473 /* turn the baudrate generator back on */
474 asc_update_bits(clear: 0, ASCCON_R, reg: port->membase + LTQ_ASC_CON);
475
476 /* enable rx */
477 __raw_writel(ASCWHBSTATE_SETREN, addr: port->membase + LTQ_ASC_WHBSTATE);
478
479 spin_unlock_irqrestore(lock: &ltq_port->lock, flags);
480
481 /* Don't rewrite B0 */
482 if (tty_termios_baud_rate(termios: new))
483 tty_termios_encode_baud_rate(termios: new, ibaud: baud, obaud: baud);
484
485 uart_update_timeout(port, cflag, baud);
486}
487
488static const char*
489lqasc_type(struct uart_port *port)
490{
491 if (port->type == PORT_LTQ_ASC)
492 return DRVNAME;
493 else
494 return NULL;
495}
496
497static void
498lqasc_release_port(struct uart_port *port)
499{
500 struct platform_device *pdev = to_platform_device(port->dev);
501
502 if (port->flags & UPF_IOREMAP) {
503 devm_iounmap(dev: &pdev->dev, addr: port->membase);
504 port->membase = NULL;
505 }
506}
507
508static int
509lqasc_request_port(struct uart_port *port)
510{
511 struct platform_device *pdev = to_platform_device(port->dev);
512 struct resource *res;
513 int size;
514
515 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
516 if (!res) {
517 dev_err(&pdev->dev, "cannot obtain I/O memory region");
518 return -ENODEV;
519 }
520 size = resource_size(res);
521
522 res = devm_request_mem_region(&pdev->dev, res->start,
523 size, dev_name(&pdev->dev));
524 if (!res) {
525 dev_err(&pdev->dev, "cannot request I/O memory region");
526 return -EBUSY;
527 }
528
529 if (port->flags & UPF_IOREMAP) {
530 port->membase = devm_ioremap(dev: &pdev->dev,
531 offset: port->mapbase, size);
532 if (port->membase == NULL)
533 return -ENOMEM;
534 }
535 return 0;
536}
537
538static void
539lqasc_config_port(struct uart_port *port, int flags)
540{
541 if (flags & UART_CONFIG_TYPE) {
542 port->type = PORT_LTQ_ASC;
543 lqasc_request_port(port);
544 }
545}
546
547static int
548lqasc_verify_port(struct uart_port *port,
549 struct serial_struct *ser)
550{
551 int ret = 0;
552 if (ser->type != PORT_UNKNOWN && ser->type != PORT_LTQ_ASC)
553 ret = -EINVAL;
554 if (ser->irq < 0 || ser->irq >= NR_IRQS)
555 ret = -EINVAL;
556 if (ser->baud_base < 9600)
557 ret = -EINVAL;
558 return ret;
559}
560
561static const struct uart_ops lqasc_pops = {
562 .tx_empty = lqasc_tx_empty,
563 .set_mctrl = lqasc_set_mctrl,
564 .get_mctrl = lqasc_get_mctrl,
565 .stop_tx = lqasc_stop_tx,
566 .start_tx = lqasc_start_tx,
567 .stop_rx = lqasc_stop_rx,
568 .break_ctl = lqasc_break_ctl,
569 .startup = lqasc_startup,
570 .shutdown = lqasc_shutdown,
571 .set_termios = lqasc_set_termios,
572 .type = lqasc_type,
573 .release_port = lqasc_release_port,
574 .request_port = lqasc_request_port,
575 .config_port = lqasc_config_port,
576 .verify_port = lqasc_verify_port,
577};
578
579#ifdef CONFIG_SERIAL_LANTIQ_CONSOLE
580static void
581lqasc_console_putchar(struct uart_port *port, unsigned char ch)
582{
583 if (!port->membase)
584 return;
585
586 while (!lqasc_tx_ready(port))
587 ;
588
589 writeb(val: ch, addr: port->membase + LTQ_ASC_TBUF);
590}
591
592static void lqasc_serial_port_write(struct uart_port *port, const char *s,
593 u_int count)
594{
595 uart_console_write(port, s, count, putchar: lqasc_console_putchar);
596}
597
598static void
599lqasc_console_write(struct console *co, const char *s, u_int count)
600{
601 struct ltq_uart_port *ltq_port;
602 unsigned long flags;
603
604 if (co->index >= MAXPORTS)
605 return;
606
607 ltq_port = lqasc_port[co->index];
608 if (!ltq_port)
609 return;
610
611 spin_lock_irqsave(&ltq_port->lock, flags);
612 lqasc_serial_port_write(port: &ltq_port->port, s, count);
613 spin_unlock_irqrestore(lock: &ltq_port->lock, flags);
614}
615
616static int __init
617lqasc_console_setup(struct console *co, char *options)
618{
619 struct ltq_uart_port *ltq_port;
620 struct uart_port *port;
621 int baud = 115200;
622 int bits = 8;
623 int parity = 'n';
624 int flow = 'n';
625
626 if (co->index >= MAXPORTS)
627 return -ENODEV;
628
629 ltq_port = lqasc_port[co->index];
630 if (!ltq_port)
631 return -ENODEV;
632
633 port = &ltq_port->port;
634
635 if (!IS_ERR(ptr: ltq_port->clk))
636 clk_prepare_enable(clk: ltq_port->clk);
637
638 port->uartclk = clk_get_rate(clk: ltq_port->freqclk);
639
640 if (options)
641 uart_parse_options(options, baud: &baud, parity: &parity, bits: &bits, flow: &flow);
642 return uart_set_options(port, co, baud, parity, bits, flow);
643}
644
645static struct console lqasc_console = {
646 .name = "ttyLTQ",
647 .write = lqasc_console_write,
648 .device = uart_console_device,
649 .setup = lqasc_console_setup,
650 .flags = CON_PRINTBUFFER,
651 .index = -1,
652 .data = &lqasc_reg,
653};
654
655static int __init
656lqasc_console_init(void)
657{
658 register_console(&lqasc_console);
659 return 0;
660}
661console_initcall(lqasc_console_init);
662
663static void lqasc_serial_early_console_write(struct console *co,
664 const char *s,
665 u_int count)
666{
667 struct earlycon_device *dev = co->data;
668
669 lqasc_serial_port_write(port: &dev->port, s, count);
670}
671
672static int __init
673lqasc_serial_early_console_setup(struct earlycon_device *device,
674 const char *opt)
675{
676 if (!device->port.membase)
677 return -ENODEV;
678
679 device->con->write = lqasc_serial_early_console_write;
680 return 0;
681}
682OF_EARLYCON_DECLARE(lantiq, "lantiq,asc", lqasc_serial_early_console_setup);
683OF_EARLYCON_DECLARE(lantiq, "intel,lgm-asc", lqasc_serial_early_console_setup);
684
685#define LANTIQ_SERIAL_CONSOLE (&lqasc_console)
686
687#else
688
689#define LANTIQ_SERIAL_CONSOLE NULL
690
691#endif /* CONFIG_SERIAL_LANTIQ_CONSOLE */
692
693static struct uart_driver lqasc_reg = {
694 .owner = THIS_MODULE,
695 .driver_name = DRVNAME,
696 .dev_name = "ttyLTQ",
697 .major = 0,
698 .minor = 0,
699 .nr = MAXPORTS,
700 .cons = LANTIQ_SERIAL_CONSOLE,
701};
702
703static int fetch_irq_lantiq(struct device *dev, struct ltq_uart_port *ltq_port)
704{
705 struct uart_port *port = &ltq_port->port;
706 struct platform_device *pdev = to_platform_device(dev);
707 int irq;
708
709 irq = platform_get_irq(pdev, 0);
710 if (irq < 0)
711 return irq;
712 ltq_port->tx_irq = irq;
713 irq = platform_get_irq(pdev, 1);
714 if (irq < 0)
715 return irq;
716 ltq_port->rx_irq = irq;
717 irq = platform_get_irq(pdev, 2);
718 if (irq < 0)
719 return irq;
720 ltq_port->err_irq = irq;
721
722 port->irq = ltq_port->tx_irq;
723
724 return 0;
725}
726
727static int request_irq_lantiq(struct uart_port *port)
728{
729 struct ltq_uart_port *ltq_port = to_ltq_uart_port(port);
730 int retval;
731
732 retval = request_irq(irq: ltq_port->tx_irq, handler: lqasc_tx_int,
733 flags: 0, name: "asc_tx", dev: port);
734 if (retval) {
735 dev_err(port->dev, "failed to request asc_tx\n");
736 return retval;
737 }
738
739 retval = request_irq(irq: ltq_port->rx_irq, handler: lqasc_rx_int,
740 flags: 0, name: "asc_rx", dev: port);
741 if (retval) {
742 dev_err(port->dev, "failed to request asc_rx\n");
743 goto err1;
744 }
745
746 retval = request_irq(irq: ltq_port->err_irq, handler: lqasc_err_int,
747 flags: 0, name: "asc_err", dev: port);
748 if (retval) {
749 dev_err(port->dev, "failed to request asc_err\n");
750 goto err2;
751 }
752 return 0;
753
754err2:
755 free_irq(ltq_port->rx_irq, port);
756err1:
757 free_irq(ltq_port->tx_irq, port);
758 return retval;
759}
760
761static void free_irq_lantiq(struct uart_port *port)
762{
763 struct ltq_uart_port *ltq_port = to_ltq_uart_port(port);
764
765 free_irq(ltq_port->tx_irq, port);
766 free_irq(ltq_port->rx_irq, port);
767 free_irq(ltq_port->err_irq, port);
768}
769
770static int fetch_irq_intel(struct device *dev, struct ltq_uart_port *ltq_port)
771{
772 struct uart_port *port = &ltq_port->port;
773 int ret;
774
775 ret = platform_get_irq(to_platform_device(dev), 0);
776 if (ret < 0)
777 return ret;
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(irq: ltq_port->common_irq, handler: lqasc_irq, flags: 0,
790 name: "asc_irq", dev: 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(dev: &pdev->dev, size: sizeof(struct ltq_uart_port),
821 GFP_KERNEL);
822 if (!ltq_port)
823 return -ENOMEM;
824
825 port = &ltq_port->port;
826
827 ltq_port->soc = of_device_get_match_data(dev: &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(np: node, stem: "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(dev: &pdev->dev, id: "freq");
866
867
868 if (IS_ERR(ptr: 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(dev: &pdev->dev, NULL);
876 else
877 ltq_port->clk = devm_clk_get(dev: &pdev->dev, id: "asc");
878
879 spin_lock_init(&ltq_port->lock);
880 lqasc_port[line] = ltq_port;
881 platform_set_drvdata(pdev, data: ltq_port);
882
883 ret = uart_add_one_port(reg: &lqasc_reg, port);
884
885 return ret;
886}
887
888static void lqasc_remove(struct platform_device *pdev)
889{
890 struct uart_port *port = platform_get_drvdata(pdev);
891
892 uart_remove_one_port(reg: &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(uart: &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(uart: &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(uart: &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");
950

source code of linux/drivers/tty/serial/lantiq.c