1// SPDX-License-Identifier: GPL-2.0+
2/*
3 * Driver for SA11x0 serial ports
4 *
5 * Based on drivers/char/serial.c, by Linus Torvalds, Theodore Ts'o.
6 *
7 * Copyright (C) 2000 Deep Blue Solutions Ltd.
8 */
9
10#include <linux/module.h>
11#include <linux/ioport.h>
12#include <linux/init.h>
13#include <linux/console.h>
14#include <linux/sysrq.h>
15#include <linux/platform_data/sa11x0-serial.h>
16#include <linux/platform_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/io.h>
22
23#include <asm/irq.h>
24#include <mach/hardware.h>
25#include <mach/irqs.h>
26
27#include "serial_mctrl_gpio.h"
28
29/* We've been assigned a range on the "Low-density serial ports" major */
30#define SERIAL_SA1100_MAJOR 204
31#define MINOR_START 5
32
33#define NR_PORTS 3
34
35#define SA1100_ISR_PASS_LIMIT 256
36
37/*
38 * Convert from ignore_status_mask or read_status_mask to UTSR[01]
39 */
40#define SM_TO_UTSR0(x) ((x) & 0xff)
41#define SM_TO_UTSR1(x) ((x) >> 8)
42#define UTSR0_TO_SM(x) ((x))
43#define UTSR1_TO_SM(x) ((x) << 8)
44
45#define UART_GET_UTCR0(sport) __raw_readl((sport)->port.membase + UTCR0)
46#define UART_GET_UTCR1(sport) __raw_readl((sport)->port.membase + UTCR1)
47#define UART_GET_UTCR2(sport) __raw_readl((sport)->port.membase + UTCR2)
48#define UART_GET_UTCR3(sport) __raw_readl((sport)->port.membase + UTCR3)
49#define UART_GET_UTSR0(sport) __raw_readl((sport)->port.membase + UTSR0)
50#define UART_GET_UTSR1(sport) __raw_readl((sport)->port.membase + UTSR1)
51#define UART_GET_CHAR(sport) __raw_readl((sport)->port.membase + UTDR)
52
53#define UART_PUT_UTCR0(sport,v) __raw_writel((v),(sport)->port.membase + UTCR0)
54#define UART_PUT_UTCR1(sport,v) __raw_writel((v),(sport)->port.membase + UTCR1)
55#define UART_PUT_UTCR2(sport,v) __raw_writel((v),(sport)->port.membase + UTCR2)
56#define UART_PUT_UTCR3(sport,v) __raw_writel((v),(sport)->port.membase + UTCR3)
57#define UART_PUT_UTSR0(sport,v) __raw_writel((v),(sport)->port.membase + UTSR0)
58#define UART_PUT_UTSR1(sport,v) __raw_writel((v),(sport)->port.membase + UTSR1)
59#define UART_PUT_CHAR(sport,v) __raw_writel((v),(sport)->port.membase + UTDR)
60
61/*
62 * This is the size of our serial port register set.
63 */
64#define UART_PORT_SIZE 0x24
65
66/*
67 * This determines how often we check the modem status signals
68 * for any change. They generally aren't connected to an IRQ
69 * so we have to poll them. We also check immediately before
70 * filling the TX fifo incase CTS has been dropped.
71 */
72#define MCTRL_TIMEOUT (250*HZ/1000)
73
74struct sa1100_port {
75 struct uart_port port;
76 struct timer_list timer;
77 unsigned int old_status;
78 struct mctrl_gpios *gpios;
79};
80
81/*
82 * Handle any change of modem status signal since we were last called.
83 */
84static void sa1100_mctrl_check(struct sa1100_port *sport)
85{
86 unsigned int status, changed;
87
88 status = sport->port.ops->get_mctrl(&sport->port);
89 changed = status ^ sport->old_status;
90
91 if (changed == 0)
92 return;
93
94 sport->old_status = status;
95
96 if (changed & TIOCM_RI)
97 sport->port.icount.rng++;
98 if (changed & TIOCM_DSR)
99 sport->port.icount.dsr++;
100 if (changed & TIOCM_CAR)
101 uart_handle_dcd_change(uport: &sport->port, active: status & TIOCM_CAR);
102 if (changed & TIOCM_CTS)
103 uart_handle_cts_change(uport: &sport->port, active: status & TIOCM_CTS);
104
105 wake_up_interruptible(&sport->port.state->port.delta_msr_wait);
106}
107
108/*
109 * This is our per-port timeout handler, for checking the
110 * modem status signals.
111 */
112static void sa1100_timeout(struct timer_list *t)
113{
114 struct sa1100_port *sport = from_timer(sport, t, timer);
115 unsigned long flags;
116
117 if (sport->port.state) {
118 uart_port_lock_irqsave(up: &sport->port, flags: &flags);
119 sa1100_mctrl_check(sport);
120 uart_port_unlock_irqrestore(up: &sport->port, flags);
121
122 mod_timer(timer: &sport->timer, expires: jiffies + MCTRL_TIMEOUT);
123 }
124}
125
126/*
127 * interrupts disabled on entry
128 */
129static void sa1100_stop_tx(struct uart_port *port)
130{
131 struct sa1100_port *sport =
132 container_of(port, struct sa1100_port, port);
133 u32 utcr3;
134
135 utcr3 = UART_GET_UTCR3(sport);
136 UART_PUT_UTCR3(sport, utcr3 & ~UTCR3_TIE);
137 sport->port.read_status_mask &= ~UTSR0_TO_SM(UTSR0_TFS);
138}
139
140/*
141 * port locked and interrupts disabled
142 */
143static void sa1100_start_tx(struct uart_port *port)
144{
145 struct sa1100_port *sport =
146 container_of(port, struct sa1100_port, port);
147 u32 utcr3;
148
149 utcr3 = UART_GET_UTCR3(sport);
150 sport->port.read_status_mask |= UTSR0_TO_SM(UTSR0_TFS);
151 UART_PUT_UTCR3(sport, utcr3 | UTCR3_TIE);
152}
153
154/*
155 * Interrupts enabled
156 */
157static void sa1100_stop_rx(struct uart_port *port)
158{
159 struct sa1100_port *sport =
160 container_of(port, struct sa1100_port, port);
161 u32 utcr3;
162
163 utcr3 = UART_GET_UTCR3(sport);
164 UART_PUT_UTCR3(sport, utcr3 & ~UTCR3_RIE);
165}
166
167/*
168 * Set the modem control timer to fire immediately.
169 */
170static void sa1100_enable_ms(struct uart_port *port)
171{
172 struct sa1100_port *sport =
173 container_of(port, struct sa1100_port, port);
174
175 mod_timer(timer: &sport->timer, expires: jiffies);
176
177 mctrl_gpio_enable_ms(gpios: sport->gpios);
178}
179
180static void
181sa1100_rx_chars(struct sa1100_port *sport)
182{
183 unsigned int status;
184 u8 ch, flg;
185
186 status = UTSR1_TO_SM(UART_GET_UTSR1(sport)) |
187 UTSR0_TO_SM(UART_GET_UTSR0(sport));
188 while (status & UTSR1_TO_SM(UTSR1_RNE)) {
189 ch = UART_GET_CHAR(sport);
190
191 sport->port.icount.rx++;
192
193 flg = TTY_NORMAL;
194
195 /*
196 * note that the error handling code is
197 * out of the main execution path
198 */
199 if (status & UTSR1_TO_SM(UTSR1_PRE | UTSR1_FRE | UTSR1_ROR)) {
200 if (status & UTSR1_TO_SM(UTSR1_PRE))
201 sport->port.icount.parity++;
202 else if (status & UTSR1_TO_SM(UTSR1_FRE))
203 sport->port.icount.frame++;
204 if (status & UTSR1_TO_SM(UTSR1_ROR))
205 sport->port.icount.overrun++;
206
207 status &= sport->port.read_status_mask;
208
209 if (status & UTSR1_TO_SM(UTSR1_PRE))
210 flg = TTY_PARITY;
211 else if (status & UTSR1_TO_SM(UTSR1_FRE))
212 flg = TTY_FRAME;
213
214 sport->port.sysrq = 0;
215 }
216
217 if (uart_handle_sysrq_char(port: &sport->port, ch))
218 goto ignore_char;
219
220 uart_insert_char(&sport->port, status, UTSR1_TO_SM(UTSR1_ROR), ch, flg);
221
222 ignore_char:
223 status = UTSR1_TO_SM(UART_GET_UTSR1(sport)) |
224 UTSR0_TO_SM(UART_GET_UTSR0(sport));
225 }
226
227 tty_flip_buffer_push(port: &sport->port.state->port);
228}
229
230static void sa1100_tx_chars(struct sa1100_port *sport)
231{
232 u8 ch;
233
234 /*
235 * Check the modem control lines before
236 * transmitting anything.
237 */
238 sa1100_mctrl_check(sport);
239
240 uart_port_tx(&sport->port, ch,
241 UART_GET_UTSR1(sport) & UTSR1_TNF,
242 UART_PUT_CHAR(sport, ch));
243}
244
245static irqreturn_t sa1100_int(int irq, void *dev_id)
246{
247 struct sa1100_port *sport = dev_id;
248 unsigned int status, pass_counter = 0;
249
250 uart_port_lock(up: &sport->port);
251 status = UART_GET_UTSR0(sport);
252 status &= SM_TO_UTSR0(sport->port.read_status_mask) | ~UTSR0_TFS;
253 do {
254 if (status & (UTSR0_RFS | UTSR0_RID)) {
255 /* Clear the receiver idle bit, if set */
256 if (status & UTSR0_RID)
257 UART_PUT_UTSR0(sport, UTSR0_RID);
258 sa1100_rx_chars(sport);
259 }
260
261 /* Clear the relevant break bits */
262 if (status & (UTSR0_RBB | UTSR0_REB))
263 UART_PUT_UTSR0(sport, status & (UTSR0_RBB | UTSR0_REB));
264
265 if (status & UTSR0_RBB)
266 sport->port.icount.brk++;
267
268 if (status & UTSR0_REB)
269 uart_handle_break(port: &sport->port);
270
271 if (status & UTSR0_TFS)
272 sa1100_tx_chars(sport);
273 if (pass_counter++ > SA1100_ISR_PASS_LIMIT)
274 break;
275 status = UART_GET_UTSR0(sport);
276 status &= SM_TO_UTSR0(sport->port.read_status_mask) |
277 ~UTSR0_TFS;
278 } while (status & (UTSR0_TFS | UTSR0_RFS | UTSR0_RID));
279 uart_port_unlock(up: &sport->port);
280
281 return IRQ_HANDLED;
282}
283
284/*
285 * Return TIOCSER_TEMT when transmitter is not busy.
286 */
287static unsigned int sa1100_tx_empty(struct uart_port *port)
288{
289 struct sa1100_port *sport =
290 container_of(port, struct sa1100_port, port);
291
292 return UART_GET_UTSR1(sport) & UTSR1_TBY ? 0 : TIOCSER_TEMT;
293}
294
295static unsigned int sa1100_get_mctrl(struct uart_port *port)
296{
297 struct sa1100_port *sport =
298 container_of(port, struct sa1100_port, port);
299 int ret = TIOCM_CTS | TIOCM_DSR | TIOCM_CAR;
300
301 mctrl_gpio_get(gpios: sport->gpios, mctrl: &ret);
302
303 return ret;
304}
305
306static void sa1100_set_mctrl(struct uart_port *port, unsigned int mctrl)
307{
308 struct sa1100_port *sport =
309 container_of(port, struct sa1100_port, port);
310
311 mctrl_gpio_set(gpios: sport->gpios, mctrl);
312}
313
314/*
315 * Interrupts always disabled.
316 */
317static void sa1100_break_ctl(struct uart_port *port, int break_state)
318{
319 struct sa1100_port *sport =
320 container_of(port, struct sa1100_port, port);
321 unsigned long flags;
322 unsigned int utcr3;
323
324 uart_port_lock_irqsave(up: &sport->port, flags: &flags);
325 utcr3 = UART_GET_UTCR3(sport);
326 if (break_state == -1)
327 utcr3 |= UTCR3_BRK;
328 else
329 utcr3 &= ~UTCR3_BRK;
330 UART_PUT_UTCR3(sport, utcr3);
331 uart_port_unlock_irqrestore(up: &sport->port, flags);
332}
333
334static int sa1100_startup(struct uart_port *port)
335{
336 struct sa1100_port *sport =
337 container_of(port, struct sa1100_port, port);
338 int retval;
339
340 /*
341 * Allocate the IRQ
342 */
343 retval = request_irq(irq: sport->port.irq, handler: sa1100_int, flags: 0,
344 name: "sa11x0-uart", dev: sport);
345 if (retval)
346 return retval;
347
348 /*
349 * Finally, clear and enable interrupts
350 */
351 UART_PUT_UTSR0(sport, -1);
352 UART_PUT_UTCR3(sport, UTCR3_RXE | UTCR3_TXE | UTCR3_RIE);
353
354 /*
355 * Enable modem status interrupts
356 */
357 uart_port_lock_irq(up: &sport->port);
358 sa1100_enable_ms(port: &sport->port);
359 uart_port_unlock_irq(up: &sport->port);
360
361 return 0;
362}
363
364static void sa1100_shutdown(struct uart_port *port)
365{
366 struct sa1100_port *sport =
367 container_of(port, struct sa1100_port, port);
368
369 /*
370 * Stop our timer.
371 */
372 del_timer_sync(timer: &sport->timer);
373
374 /*
375 * Free the interrupt
376 */
377 free_irq(sport->port.irq, sport);
378
379 /*
380 * Disable all interrupts, port and break condition.
381 */
382 UART_PUT_UTCR3(sport, 0);
383}
384
385static void
386sa1100_set_termios(struct uart_port *port, struct ktermios *termios,
387 const struct ktermios *old)
388{
389 struct sa1100_port *sport =
390 container_of(port, struct sa1100_port, port);
391 unsigned long flags;
392 unsigned int utcr0, old_utcr3, baud, quot;
393 unsigned int old_csize = old ? old->c_cflag & CSIZE : CS8;
394
395 /*
396 * We only support CS7 and CS8.
397 */
398 while ((termios->c_cflag & CSIZE) != CS7 &&
399 (termios->c_cflag & CSIZE) != CS8) {
400 termios->c_cflag &= ~CSIZE;
401 termios->c_cflag |= old_csize;
402 old_csize = CS8;
403 }
404
405 if ((termios->c_cflag & CSIZE) == CS8)
406 utcr0 = UTCR0_DSS;
407 else
408 utcr0 = 0;
409
410 if (termios->c_cflag & CSTOPB)
411 utcr0 |= UTCR0_SBS;
412 if (termios->c_cflag & PARENB) {
413 utcr0 |= UTCR0_PE;
414 if (!(termios->c_cflag & PARODD))
415 utcr0 |= UTCR0_OES;
416 }
417
418 /*
419 * Ask the core to calculate the divisor for us.
420 */
421 baud = uart_get_baud_rate(port, termios, old, min: 0, max: port->uartclk/16);
422 quot = uart_get_divisor(port, baud);
423
424 del_timer_sync(timer: &sport->timer);
425
426 uart_port_lock_irqsave(up: &sport->port, flags: &flags);
427
428 sport->port.read_status_mask &= UTSR0_TO_SM(UTSR0_TFS);
429 sport->port.read_status_mask |= UTSR1_TO_SM(UTSR1_ROR);
430 if (termios->c_iflag & INPCK)
431 sport->port.read_status_mask |=
432 UTSR1_TO_SM(UTSR1_FRE | UTSR1_PRE);
433 if (termios->c_iflag & (BRKINT | PARMRK))
434 sport->port.read_status_mask |=
435 UTSR0_TO_SM(UTSR0_RBB | UTSR0_REB);
436
437 /*
438 * Characters to ignore
439 */
440 sport->port.ignore_status_mask = 0;
441 if (termios->c_iflag & IGNPAR)
442 sport->port.ignore_status_mask |=
443 UTSR1_TO_SM(UTSR1_FRE | UTSR1_PRE);
444 if (termios->c_iflag & IGNBRK) {
445 sport->port.ignore_status_mask |=
446 UTSR0_TO_SM(UTSR0_RBB | UTSR0_REB);
447 /*
448 * If we're ignoring parity and break indicators,
449 * ignore overruns too (for real raw support).
450 */
451 if (termios->c_iflag & IGNPAR)
452 sport->port.ignore_status_mask |=
453 UTSR1_TO_SM(UTSR1_ROR);
454 }
455
456 /*
457 * Update the per-port timeout.
458 */
459 uart_update_timeout(port, cflag: termios->c_cflag, baud);
460
461 /*
462 * disable interrupts and drain transmitter
463 */
464 old_utcr3 = UART_GET_UTCR3(sport);
465 UART_PUT_UTCR3(sport, old_utcr3 & ~(UTCR3_RIE | UTCR3_TIE));
466
467 while (UART_GET_UTSR1(sport) & UTSR1_TBY)
468 barrier();
469
470 /* then, disable everything */
471 UART_PUT_UTCR3(sport, 0);
472
473 /* set the parity, stop bits and data size */
474 UART_PUT_UTCR0(sport, utcr0);
475
476 /* set the baud rate */
477 quot -= 1;
478 UART_PUT_UTCR1(sport, ((quot & 0xf00) >> 8));
479 UART_PUT_UTCR2(sport, (quot & 0xff));
480
481 UART_PUT_UTSR0(sport, -1);
482
483 UART_PUT_UTCR3(sport, old_utcr3);
484
485 if (UART_ENABLE_MS(&sport->port, termios->c_cflag))
486 sa1100_enable_ms(port: &sport->port);
487
488 uart_port_unlock_irqrestore(up: &sport->port, flags);
489}
490
491static const char *sa1100_type(struct uart_port *port)
492{
493 struct sa1100_port *sport =
494 container_of(port, struct sa1100_port, port);
495
496 return sport->port.type == PORT_SA1100 ? "SA1100" : NULL;
497}
498
499/*
500 * Release the memory region(s) being used by 'port'.
501 */
502static void sa1100_release_port(struct uart_port *port)
503{
504 struct sa1100_port *sport =
505 container_of(port, struct sa1100_port, port);
506
507 release_mem_region(sport->port.mapbase, UART_PORT_SIZE);
508}
509
510/*
511 * Request the memory region(s) being used by 'port'.
512 */
513static int sa1100_request_port(struct uart_port *port)
514{
515 struct sa1100_port *sport =
516 container_of(port, struct sa1100_port, port);
517
518 return request_mem_region(sport->port.mapbase, UART_PORT_SIZE,
519 "sa11x0-uart") != NULL ? 0 : -EBUSY;
520}
521
522/*
523 * Configure/autoconfigure the port.
524 */
525static void sa1100_config_port(struct uart_port *port, int flags)
526{
527 struct sa1100_port *sport =
528 container_of(port, struct sa1100_port, port);
529
530 if (flags & UART_CONFIG_TYPE &&
531 sa1100_request_port(port: &sport->port) == 0)
532 sport->port.type = PORT_SA1100;
533}
534
535/*
536 * Verify the new serial_struct (for TIOCSSERIAL).
537 * The only change we allow are to the flags and type, and
538 * even then only between PORT_SA1100 and PORT_UNKNOWN
539 */
540static int
541sa1100_verify_port(struct uart_port *port, struct serial_struct *ser)
542{
543 struct sa1100_port *sport =
544 container_of(port, struct sa1100_port, port);
545 int ret = 0;
546
547 if (ser->type != PORT_UNKNOWN && ser->type != PORT_SA1100)
548 ret = -EINVAL;
549 if (sport->port.irq != ser->irq)
550 ret = -EINVAL;
551 if (ser->io_type != SERIAL_IO_MEM)
552 ret = -EINVAL;
553 if (sport->port.uartclk / 16 != ser->baud_base)
554 ret = -EINVAL;
555 if ((void *)sport->port.mapbase != ser->iomem_base)
556 ret = -EINVAL;
557 if (sport->port.iobase != ser->port)
558 ret = -EINVAL;
559 if (ser->hub6 != 0)
560 ret = -EINVAL;
561 return ret;
562}
563
564static struct uart_ops sa1100_pops = {
565 .tx_empty = sa1100_tx_empty,
566 .set_mctrl = sa1100_set_mctrl,
567 .get_mctrl = sa1100_get_mctrl,
568 .stop_tx = sa1100_stop_tx,
569 .start_tx = sa1100_start_tx,
570 .stop_rx = sa1100_stop_rx,
571 .enable_ms = sa1100_enable_ms,
572 .break_ctl = sa1100_break_ctl,
573 .startup = sa1100_startup,
574 .shutdown = sa1100_shutdown,
575 .set_termios = sa1100_set_termios,
576 .type = sa1100_type,
577 .release_port = sa1100_release_port,
578 .request_port = sa1100_request_port,
579 .config_port = sa1100_config_port,
580 .verify_port = sa1100_verify_port,
581};
582
583static struct sa1100_port sa1100_ports[NR_PORTS];
584
585/*
586 * Setup the SA1100 serial ports. Note that we don't include the IrDA
587 * port here since we have our own SIR/FIR driver (see drivers/net/irda)
588 *
589 * Note also that we support "console=ttySAx" where "x" is either 0 or 1.
590 * Which serial port this ends up being depends on the machine you're
591 * running this kernel on. I'm not convinced that this is a good idea,
592 * but that's the way it traditionally works.
593 *
594 * Note that NanoEngine UART3 becomes UART2, and UART2 is no longer
595 * used here.
596 */
597static void __init sa1100_init_ports(void)
598{
599 static int first = 1;
600 int i;
601
602 if (!first)
603 return;
604 first = 0;
605
606 for (i = 0; i < NR_PORTS; i++) {
607 sa1100_ports[i].port.uartclk = 3686400;
608 sa1100_ports[i].port.ops = &sa1100_pops;
609 sa1100_ports[i].port.fifosize = 8;
610 sa1100_ports[i].port.line = i;
611 sa1100_ports[i].port.iotype = UPIO_MEM;
612 timer_setup(&sa1100_ports[i].timer, sa1100_timeout, 0);
613 }
614
615 /*
616 * make transmit lines outputs, so that when the port
617 * is closed, the output is in the MARK state.
618 */
619 PPDR |= PPC_TXD1 | PPC_TXD3;
620 PPSR |= PPC_TXD1 | PPC_TXD3;
621}
622
623void sa1100_register_uart_fns(struct sa1100_port_fns *fns)
624{
625 if (fns->get_mctrl)
626 sa1100_pops.get_mctrl = fns->get_mctrl;
627 if (fns->set_mctrl)
628 sa1100_pops.set_mctrl = fns->set_mctrl;
629
630 sa1100_pops.pm = fns->pm;
631 /*
632 * FIXME: fns->set_wake is unused - this should be called from
633 * the suspend() callback if device_may_wakeup(dev)) is set.
634 */
635}
636
637void __init sa1100_register_uart(int idx, int port)
638{
639 if (idx >= NR_PORTS) {
640 printk(KERN_ERR "%s: bad index number %d\n", __func__, idx);
641 return;
642 }
643
644 switch (port) {
645 case 1:
646 sa1100_ports[idx].port.membase = (void __iomem *)&Ser1UTCR0;
647 sa1100_ports[idx].port.mapbase = _Ser1UTCR0;
648 sa1100_ports[idx].port.irq = IRQ_Ser1UART;
649 sa1100_ports[idx].port.flags = UPF_BOOT_AUTOCONF;
650 break;
651
652 case 2:
653 sa1100_ports[idx].port.membase = (void __iomem *)&Ser2UTCR0;
654 sa1100_ports[idx].port.mapbase = _Ser2UTCR0;
655 sa1100_ports[idx].port.irq = IRQ_Ser2ICP;
656 sa1100_ports[idx].port.flags = UPF_BOOT_AUTOCONF;
657 break;
658
659 case 3:
660 sa1100_ports[idx].port.membase = (void __iomem *)&Ser3UTCR0;
661 sa1100_ports[idx].port.mapbase = _Ser3UTCR0;
662 sa1100_ports[idx].port.irq = IRQ_Ser3UART;
663 sa1100_ports[idx].port.flags = UPF_BOOT_AUTOCONF;
664 break;
665
666 default:
667 printk(KERN_ERR "%s: bad port number %d\n", __func__, port);
668 }
669}
670
671
672#ifdef CONFIG_SERIAL_SA1100_CONSOLE
673static void sa1100_console_putchar(struct uart_port *port, unsigned char ch)
674{
675 struct sa1100_port *sport =
676 container_of(port, struct sa1100_port, port);
677
678 while (!(UART_GET_UTSR1(sport) & UTSR1_TNF))
679 barrier();
680 UART_PUT_CHAR(sport, ch);
681}
682
683/*
684 * Interrupts are disabled on entering
685 */
686static void
687sa1100_console_write(struct console *co, const char *s, unsigned int count)
688{
689 struct sa1100_port *sport = &sa1100_ports[co->index];
690 unsigned int old_utcr3, status;
691
692 /*
693 * First, save UTCR3 and then disable interrupts
694 */
695 old_utcr3 = UART_GET_UTCR3(sport);
696 UART_PUT_UTCR3(sport, (old_utcr3 & ~(UTCR3_RIE | UTCR3_TIE)) |
697 UTCR3_TXE);
698
699 uart_console_write(&sport->port, s, count, sa1100_console_putchar);
700
701 /*
702 * Finally, wait for transmitter to become empty
703 * and restore UTCR3
704 */
705 do {
706 status = UART_GET_UTSR1(sport);
707 } while (status & UTSR1_TBY);
708 UART_PUT_UTCR3(sport, old_utcr3);
709}
710
711/*
712 * If the port was already initialised (eg, by a boot loader),
713 * try to determine the current setup.
714 */
715static void __init
716sa1100_console_get_options(struct sa1100_port *sport, int *baud,
717 int *parity, int *bits)
718{
719 unsigned int utcr3;
720
721 utcr3 = UART_GET_UTCR3(sport) & (UTCR3_RXE | UTCR3_TXE);
722 if (utcr3 == (UTCR3_RXE | UTCR3_TXE)) {
723 /* ok, the port was enabled */
724 unsigned int utcr0, quot;
725
726 utcr0 = UART_GET_UTCR0(sport);
727
728 *parity = 'n';
729 if (utcr0 & UTCR0_PE) {
730 if (utcr0 & UTCR0_OES)
731 *parity = 'e';
732 else
733 *parity = 'o';
734 }
735
736 if (utcr0 & UTCR0_DSS)
737 *bits = 8;
738 else
739 *bits = 7;
740
741 quot = UART_GET_UTCR2(sport) | UART_GET_UTCR1(sport) << 8;
742 quot &= 0xfff;
743 *baud = sport->port.uartclk / (16 * (quot + 1));
744 }
745}
746
747static int __init
748sa1100_console_setup(struct console *co, char *options)
749{
750 struct sa1100_port *sport;
751 int baud = 9600;
752 int bits = 8;
753 int parity = 'n';
754 int flow = 'n';
755
756 /*
757 * Check whether an invalid uart number has been specified, and
758 * if so, search for the first available port that does have
759 * console support.
760 */
761 if (co->index == -1 || co->index >= NR_PORTS)
762 co->index = 0;
763 sport = &sa1100_ports[co->index];
764
765 if (options)
766 uart_parse_options(options, &baud, &parity, &bits, &flow);
767 else
768 sa1100_console_get_options(sport, &baud, &parity, &bits);
769
770 return uart_set_options(&sport->port, co, baud, parity, bits, flow);
771}
772
773static struct uart_driver sa1100_reg;
774static struct console sa1100_console = {
775 .name = "ttySA",
776 .write = sa1100_console_write,
777 .device = uart_console_device,
778 .setup = sa1100_console_setup,
779 .flags = CON_PRINTBUFFER,
780 .index = -1,
781 .data = &sa1100_reg,
782};
783
784static int __init sa1100_rs_console_init(void)
785{
786 sa1100_init_ports();
787 register_console(&sa1100_console);
788 return 0;
789}
790console_initcall(sa1100_rs_console_init);
791
792#define SA1100_CONSOLE &sa1100_console
793#else
794#define SA1100_CONSOLE NULL
795#endif
796
797static struct uart_driver sa1100_reg = {
798 .owner = THIS_MODULE,
799 .driver_name = "ttySA",
800 .dev_name = "ttySA",
801 .major = SERIAL_SA1100_MAJOR,
802 .minor = MINOR_START,
803 .nr = NR_PORTS,
804 .cons = SA1100_CONSOLE,
805};
806
807static int sa1100_serial_suspend(struct platform_device *dev, pm_message_t state)
808{
809 struct sa1100_port *sport = platform_get_drvdata(pdev: dev);
810
811 if (sport)
812 uart_suspend_port(reg: &sa1100_reg, port: &sport->port);
813
814 return 0;
815}
816
817static int sa1100_serial_resume(struct platform_device *dev)
818{
819 struct sa1100_port *sport = platform_get_drvdata(pdev: dev);
820
821 if (sport)
822 uart_resume_port(reg: &sa1100_reg, port: &sport->port);
823
824 return 0;
825}
826
827static int sa1100_serial_add_one_port(struct sa1100_port *sport, struct platform_device *dev)
828{
829 sport->port.dev = &dev->dev;
830 sport->port.has_sysrq = IS_ENABLED(CONFIG_SERIAL_SA1100_CONSOLE);
831
832 // mctrl_gpio_init() requires that the GPIO driver supports interrupts,
833 // but we need to support GPIO drivers for hardware that has no such
834 // interrupts. Use mctrl_gpio_init_noauto() instead.
835 sport->gpios = mctrl_gpio_init_noauto(dev: sport->port.dev, idx: 0);
836 if (IS_ERR(ptr: sport->gpios)) {
837 int err = PTR_ERR(ptr: sport->gpios);
838
839 dev_err(sport->port.dev, "failed to get mctrl gpios: %d\n",
840 err);
841
842 if (err == -EPROBE_DEFER)
843 return err;
844
845 sport->gpios = NULL;
846 }
847
848 platform_set_drvdata(pdev: dev, data: sport);
849
850 return uart_add_one_port(reg: &sa1100_reg, port: &sport->port);
851}
852
853static int sa1100_serial_probe(struct platform_device *dev)
854{
855 struct resource *res;
856 int i;
857
858 res = platform_get_resource(dev, IORESOURCE_MEM, 0);
859 if (!res)
860 return -EINVAL;
861
862 for (i = 0; i < NR_PORTS; i++)
863 if (sa1100_ports[i].port.mapbase == res->start)
864 break;
865 if (i == NR_PORTS)
866 return -ENODEV;
867
868 sa1100_serial_add_one_port(sport: &sa1100_ports[i], dev);
869
870 return 0;
871}
872
873static int sa1100_serial_remove(struct platform_device *pdev)
874{
875 struct sa1100_port *sport = platform_get_drvdata(pdev);
876
877 if (sport)
878 uart_remove_one_port(reg: &sa1100_reg, port: &sport->port);
879
880 return 0;
881}
882
883static struct platform_driver sa11x0_serial_driver = {
884 .probe = sa1100_serial_probe,
885 .remove = sa1100_serial_remove,
886 .suspend = sa1100_serial_suspend,
887 .resume = sa1100_serial_resume,
888 .driver = {
889 .name = "sa11x0-uart",
890 },
891};
892
893static int __init sa1100_serial_init(void)
894{
895 int ret;
896
897 printk(KERN_INFO "Serial: SA11x0 driver\n");
898
899 sa1100_init_ports();
900
901 ret = uart_register_driver(uart: &sa1100_reg);
902 if (ret == 0) {
903 ret = platform_driver_register(&sa11x0_serial_driver);
904 if (ret)
905 uart_unregister_driver(uart: &sa1100_reg);
906 }
907 return ret;
908}
909
910static void __exit sa1100_serial_exit(void)
911{
912 platform_driver_unregister(&sa11x0_serial_driver);
913 uart_unregister_driver(uart: &sa1100_reg);
914}
915
916module_init(sa1100_serial_init);
917module_exit(sa1100_serial_exit);
918
919MODULE_AUTHOR("Deep Blue Solutions Ltd");
920MODULE_DESCRIPTION("SA1100 generic serial port driver");
921MODULE_LICENSE("GPL");
922MODULE_ALIAS_CHARDEV_MAJOR(SERIAL_SA1100_MAJOR);
923MODULE_ALIAS("platform:sa11x0-uart");
924

source code of linux/drivers/tty/serial/sa1100.c