Loading...
1// SPDX-License-Identifier: GPL-2.0+
2/*
3 * Based on drivers/serial/8250.c by Russell King.
4 *
5 * Author: Nicolas Pitre
6 * Created: Feb 20, 2003
7 * Copyright: (C) 2003 Monta Vista Software, Inc.
8 *
9 * Note 1: This driver is made separate from the already too overloaded
10 * 8250.c because it needs some kirks of its own and that'll make it
11 * easier to add DMA support.
12 *
13 * Note 2: I'm too sick of device allocation policies for serial ports.
14 * If someone else wants to request an "official" allocation of major/minor
15 * for this driver please be my guest. And don't forget that new hardware
16 * to come from Intel might have more than 3 or 4 of those UARTs. Let's
17 * hope for a better port registration and dynamic device allocation scheme
18 * with the serial core maintainer satisfaction to appear soon.
19 */
20
21
22#include <linux/ioport.h>
23#include <linux/init.h>
24#include <linux/console.h>
25#include <linux/sysrq.h>
26#include <linux/serial.h>
27#include <linux/serial_reg.h>
28#include <linux/circ_buf.h>
29#include <linux/delay.h>
30#include <linux/interrupt.h>
31#include <linux/of.h>
32#include <linux/platform_device.h>
33#include <linux/tty.h>
34#include <linux/tty_flip.h>
35#include <linux/serial_core.h>
36#include <linux/clk.h>
37#include <linux/io.h>
38#include <linux/slab.h>
39
40#define PXA_NAME_LEN 8
41
42struct uart_pxa_port {
43 struct uart_port port;
44 unsigned char ier;
45 unsigned char lcr;
46 unsigned char mcr;
47 unsigned int lsr_break_flag;
48 struct clk *clk;
49 char name[PXA_NAME_LEN];
50};
51
52static inline unsigned int serial_in(struct uart_pxa_port *up, int offset)
53{
54 offset <<= 2;
55 return readl(up->port.membase + offset);
56}
57
58static inline void serial_out(struct uart_pxa_port *up, int offset, int value)
59{
60 offset <<= 2;
61 writel(value, up->port.membase + offset);
62}
63
64static void serial_pxa_enable_ms(struct uart_port *port)
65{
66 struct uart_pxa_port *up = (struct uart_pxa_port *)port;
67
68 up->ier |= UART_IER_MSI;
69 serial_out(up, UART_IER, up->ier);
70}
71
72static void serial_pxa_stop_tx(struct uart_port *port)
73{
74 struct uart_pxa_port *up = (struct uart_pxa_port *)port;
75
76 if (up->ier & UART_IER_THRI) {
77 up->ier &= ~UART_IER_THRI;
78 serial_out(up, UART_IER, up->ier);
79 }
80}
81
82static void serial_pxa_stop_rx(struct uart_port *port)
83{
84 struct uart_pxa_port *up = (struct uart_pxa_port *)port;
85
86 up->ier &= ~UART_IER_RLSI;
87 up->port.read_status_mask &= ~UART_LSR_DR;
88 serial_out(up, UART_IER, up->ier);
89}
90
91static inline void receive_chars(struct uart_pxa_port *up, int *status)
92{
93 u8 ch, flag;
94 int max_count = 256;
95
96 do {
97 /* work around Errata #20 according to
98 * Intel(R) PXA27x Processor Family
99 * Specification Update (May 2005)
100 *
101 * Step 2
102 * Disable the Reciever Time Out Interrupt via IER[RTOEI]
103 */
104 up->ier &= ~UART_IER_RTOIE;
105 serial_out(up, UART_IER, up->ier);
106
107 ch = serial_in(up, UART_RX);
108 flag = TTY_NORMAL;
109 up->port.icount.rx++;
110
111 if (unlikely(*status & (UART_LSR_BI | UART_LSR_PE |
112 UART_LSR_FE | UART_LSR_OE))) {
113 /*
114 * For statistics only
115 */
116 if (*status & UART_LSR_BI) {
117 *status &= ~(UART_LSR_FE | UART_LSR_PE);
118 up->port.icount.brk++;
119 /*
120 * We do the SysRQ and SAK checking
121 * here because otherwise the break
122 * may get masked by ignore_status_mask
123 * or read_status_mask.
124 */
125 if (uart_handle_break(&up->port))
126 goto ignore_char;
127 } else if (*status & UART_LSR_PE)
128 up->port.icount.parity++;
129 else if (*status & UART_LSR_FE)
130 up->port.icount.frame++;
131 if (*status & UART_LSR_OE)
132 up->port.icount.overrun++;
133
134 /*
135 * Mask off conditions which should be ignored.
136 */
137 *status &= up->port.read_status_mask;
138
139#ifdef CONFIG_SERIAL_PXA_CONSOLE
140 if (up->port.line == up->port.cons->index) {
141 /* Recover the break flag from console xmit */
142 *status |= up->lsr_break_flag;
143 up->lsr_break_flag = 0;
144 }
145#endif
146 if (*status & UART_LSR_BI) {
147 flag = TTY_BREAK;
148 } else if (*status & UART_LSR_PE)
149 flag = TTY_PARITY;
150 else if (*status & UART_LSR_FE)
151 flag = TTY_FRAME;
152 }
153
154 if (uart_handle_sysrq_char(&up->port, ch))
155 goto ignore_char;
156
157 uart_insert_char(&up->port, *status, UART_LSR_OE, ch, flag);
158
159 ignore_char:
160 *status = serial_in(up, UART_LSR);
161 } while ((*status & UART_LSR_DR) && (max_count-- > 0));
162 tty_flip_buffer_push(&up->port.state->port);
163
164 /* work around Errata #20 according to
165 * Intel(R) PXA27x Processor Family
166 * Specification Update (May 2005)
167 *
168 * Step 6:
169 * No more data in FIFO: Re-enable RTO interrupt via IER[RTOIE]
170 */
171 up->ier |= UART_IER_RTOIE;
172 serial_out(up, UART_IER, up->ier);
173}
174
175static void transmit_chars(struct uart_pxa_port *up)
176{
177 u8 ch;
178
179 uart_port_tx_limited(&up->port, ch, up->port.fifosize / 2,
180 true,
181 serial_out(up, UART_TX, ch),
182 ({}));
183}
184
185static void serial_pxa_start_tx(struct uart_port *port)
186{
187 struct uart_pxa_port *up = (struct uart_pxa_port *)port;
188
189 if (!(up->ier & UART_IER_THRI)) {
190 up->ier |= UART_IER_THRI;
191 serial_out(up, UART_IER, up->ier);
192 }
193}
194
195/* should hold up->port.lock */
196static inline void check_modem_status(struct uart_pxa_port *up)
197{
198 int status;
199
200 status = serial_in(up, UART_MSR);
201
202 if ((status & UART_MSR_ANY_DELTA) == 0)
203 return;
204
205 if (status & UART_MSR_TERI)
206 up->port.icount.rng++;
207 if (status & UART_MSR_DDSR)
208 up->port.icount.dsr++;
209 if (status & UART_MSR_DDCD)
210 uart_handle_dcd_change(&up->port, status & UART_MSR_DCD);
211 if (status & UART_MSR_DCTS)
212 uart_handle_cts_change(&up->port, status & UART_MSR_CTS);
213
214 wake_up_interruptible(&up->port.state->port.delta_msr_wait);
215}
216
217/*
218 * This handles the interrupt from one port.
219 */
220static inline irqreturn_t serial_pxa_irq(int irq, void *dev_id)
221{
222 struct uart_pxa_port *up = dev_id;
223 unsigned int iir, lsr;
224
225 iir = serial_in(up, UART_IIR);
226 if (iir & UART_IIR_NO_INT)
227 return IRQ_NONE;
228 uart_port_lock(&up->port);
229 lsr = serial_in(up, UART_LSR);
230 if (lsr & UART_LSR_DR)
231 receive_chars(up, &lsr);
232 check_modem_status(up);
233 if (lsr & UART_LSR_THRE)
234 transmit_chars(up);
235 uart_port_unlock(&up->port);
236 return IRQ_HANDLED;
237}
238
239static unsigned int serial_pxa_tx_empty(struct uart_port *port)
240{
241 struct uart_pxa_port *up = (struct uart_pxa_port *)port;
242 unsigned long flags;
243 unsigned int ret;
244
245 uart_port_lock_irqsave(&up->port, &flags);
246 ret = serial_in(up, UART_LSR) & UART_LSR_TEMT ? TIOCSER_TEMT : 0;
247 uart_port_unlock_irqrestore(&up->port, flags);
248
249 return ret;
250}
251
252static unsigned int serial_pxa_get_mctrl(struct uart_port *port)
253{
254 struct uart_pxa_port *up = (struct uart_pxa_port *)port;
255 unsigned char status;
256 unsigned int ret;
257
258 status = serial_in(up, UART_MSR);
259
260 ret = 0;
261 if (status & UART_MSR_DCD)
262 ret |= TIOCM_CAR;
263 if (status & UART_MSR_RI)
264 ret |= TIOCM_RNG;
265 if (status & UART_MSR_DSR)
266 ret |= TIOCM_DSR;
267 if (status & UART_MSR_CTS)
268 ret |= TIOCM_CTS;
269 return ret;
270}
271
272static void serial_pxa_set_mctrl(struct uart_port *port, unsigned int mctrl)
273{
274 struct uart_pxa_port *up = (struct uart_pxa_port *)port;
275 unsigned char mcr = 0;
276
277 if (mctrl & TIOCM_RTS)
278 mcr |= UART_MCR_RTS;
279 if (mctrl & TIOCM_DTR)
280 mcr |= UART_MCR_DTR;
281 if (mctrl & TIOCM_OUT1)
282 mcr |= UART_MCR_OUT1;
283 if (mctrl & TIOCM_OUT2)
284 mcr |= UART_MCR_OUT2;
285 if (mctrl & TIOCM_LOOP)
286 mcr |= UART_MCR_LOOP;
287
288 mcr |= up->mcr;
289
290 serial_out(up, UART_MCR, mcr);
291}
292
293static void serial_pxa_break_ctl(struct uart_port *port, int break_state)
294{
295 struct uart_pxa_port *up = (struct uart_pxa_port *)port;
296 unsigned long flags;
297
298 uart_port_lock_irqsave(&up->port, &flags);
299 if (break_state == -1)
300 up->lcr |= UART_LCR_SBC;
301 else
302 up->lcr &= ~UART_LCR_SBC;
303 serial_out(up, UART_LCR, up->lcr);
304 uart_port_unlock_irqrestore(&up->port, flags);
305}
306
307static int serial_pxa_startup(struct uart_port *port)
308{
309 struct uart_pxa_port *up = (struct uart_pxa_port *)port;
310 unsigned long flags;
311 int retval;
312
313 if (port->line == 3) /* HWUART */
314 up->mcr |= UART_MCR_AFE;
315 else
316 up->mcr = 0;
317
318 up->port.uartclk = clk_get_rate(up->clk);
319
320 /*
321 * Allocate the IRQ
322 */
323 retval = request_irq(up->port.irq, serial_pxa_irq, 0, up->name, up);
324 if (retval)
325 return retval;
326
327 /*
328 * Clear the FIFO buffers and disable them.
329 * (they will be reenabled in set_termios())
330 */
331 serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO);
332 serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO |
333 UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT);
334 serial_out(up, UART_FCR, 0);
335
336 /*
337 * Clear the interrupt registers.
338 */
339 (void) serial_in(up, UART_LSR);
340 (void) serial_in(up, UART_RX);
341 (void) serial_in(up, UART_IIR);
342 (void) serial_in(up, UART_MSR);
343
344 /*
345 * Now, initialize the UART
346 */
347 serial_out(up, UART_LCR, UART_LCR_WLEN8);
348
349 uart_port_lock_irqsave(&up->port, &flags);
350 up->port.mctrl |= TIOCM_OUT2;
351 serial_pxa_set_mctrl(&up->port, up->port.mctrl);
352 uart_port_unlock_irqrestore(&up->port, flags);
353
354 /*
355 * Finally, enable interrupts. Note: Modem status interrupts
356 * are set via set_termios(), which will be occurring imminently
357 * anyway, so we don't enable them here.
358 */
359 up->ier = UART_IER_RLSI | UART_IER_RDI | UART_IER_RTOIE | UART_IER_UUE;
360 serial_out(up, UART_IER, up->ier);
361
362 /*
363 * And clear the interrupt registers again for luck.
364 */
365 (void) serial_in(up, UART_LSR);
366 (void) serial_in(up, UART_RX);
367 (void) serial_in(up, UART_IIR);
368 (void) serial_in(up, UART_MSR);
369
370 return 0;
371}
372
373static void serial_pxa_shutdown(struct uart_port *port)
374{
375 struct uart_pxa_port *up = (struct uart_pxa_port *)port;
376 unsigned long flags;
377
378 free_irq(up->port.irq, up);
379
380 /*
381 * Disable interrupts from this port
382 */
383 up->ier = 0;
384 serial_out(up, UART_IER, 0);
385
386 uart_port_lock_irqsave(&up->port, &flags);
387 up->port.mctrl &= ~TIOCM_OUT2;
388 serial_pxa_set_mctrl(&up->port, up->port.mctrl);
389 uart_port_unlock_irqrestore(&up->port, flags);
390
391 /*
392 * Disable break condition and FIFOs
393 */
394 serial_out(up, UART_LCR, serial_in(up, UART_LCR) & ~UART_LCR_SBC);
395 serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO |
396 UART_FCR_CLEAR_RCVR |
397 UART_FCR_CLEAR_XMIT);
398 serial_out(up, UART_FCR, 0);
399}
400
401static void
402serial_pxa_set_termios(struct uart_port *port, struct ktermios *termios,
403 const struct ktermios *old)
404{
405 struct uart_pxa_port *up = (struct uart_pxa_port *)port;
406 unsigned char cval, fcr = 0;
407 unsigned long flags;
408 unsigned int baud, quot;
409 unsigned int dll;
410
411 cval = UART_LCR_WLEN(tty_get_char_size(termios->c_cflag));
412
413 if (termios->c_cflag & CSTOPB)
414 cval |= UART_LCR_STOP;
415 if (termios->c_cflag & PARENB)
416 cval |= UART_LCR_PARITY;
417 if (!(termios->c_cflag & PARODD))
418 cval |= UART_LCR_EPAR;
419
420 /*
421 * Ask the core to calculate the divisor for us.
422 */
423 baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk/16);
424 quot = uart_get_divisor(port, baud);
425
426 if ((up->port.uartclk / quot) < (2400 * 16))
427 fcr = UART_FCR_ENABLE_FIFO | UART_FCR_PXAR1;
428 else if ((up->port.uartclk / quot) < (230400 * 16))
429 fcr = UART_FCR_ENABLE_FIFO | UART_FCR_PXAR8;
430 else
431 fcr = UART_FCR_ENABLE_FIFO | UART_FCR_PXAR32;
432
433 /*
434 * Ok, we're now changing the port state. Do it with
435 * interrupts disabled.
436 */
437 uart_port_lock_irqsave(&up->port, &flags);
438
439 /*
440 * Ensure the port will be enabled.
441 * This is required especially for serial console.
442 */
443 up->ier |= UART_IER_UUE;
444
445 /*
446 * Update the per-port timeout.
447 */
448 uart_update_timeout(port, termios->c_cflag, baud);
449
450 up->port.read_status_mask = UART_LSR_OE | UART_LSR_THRE | UART_LSR_DR;
451 if (termios->c_iflag & INPCK)
452 up->port.read_status_mask |= UART_LSR_FE | UART_LSR_PE;
453 if (termios->c_iflag & (IGNBRK | BRKINT | PARMRK))
454 up->port.read_status_mask |= UART_LSR_BI;
455
456 /*
457 * Characters to ignore
458 */
459 up->port.ignore_status_mask = 0;
460 if (termios->c_iflag & IGNPAR)
461 up->port.ignore_status_mask |= UART_LSR_PE | UART_LSR_FE;
462 if (termios->c_iflag & IGNBRK) {
463 up->port.ignore_status_mask |= UART_LSR_BI;
464 /*
465 * If we're ignoring parity and break indicators,
466 * ignore overruns too (for real raw support).
467 */
468 if (termios->c_iflag & IGNPAR)
469 up->port.ignore_status_mask |= UART_LSR_OE;
470 }
471
472 /*
473 * ignore all characters if CREAD is not set
474 */
475 if ((termios->c_cflag & CREAD) == 0)
476 up->port.ignore_status_mask |= UART_LSR_DR;
477
478 /*
479 * CTS flow control flag and modem status interrupts
480 */
481 up->ier &= ~UART_IER_MSI;
482 if (UART_ENABLE_MS(&up->port, termios->c_cflag))
483 up->ier |= UART_IER_MSI;
484
485 serial_out(up, UART_IER, up->ier);
486
487 if (termios->c_cflag & CRTSCTS)
488 up->mcr |= UART_MCR_AFE;
489 else
490 up->mcr &= ~UART_MCR_AFE;
491
492 serial_out(up, UART_LCR, cval | UART_LCR_DLAB); /* set DLAB */
493 serial_out(up, UART_DLL, quot & 0xff); /* LS of divisor */
494
495 /*
496 * work around Errata #75 according to Intel(R) PXA27x Processor Family
497 * Specification Update (Nov 2005)
498 */
499 dll = serial_in(up, UART_DLL);
500 WARN_ON(dll != (quot & 0xff));
501
502 serial_out(up, UART_DLM, quot >> 8); /* MS of divisor */
503 serial_out(up, UART_LCR, cval); /* reset DLAB */
504 up->lcr = cval; /* Save LCR */
505 serial_pxa_set_mctrl(&up->port, up->port.mctrl);
506 serial_out(up, UART_FCR, fcr);
507 uart_port_unlock_irqrestore(&up->port, flags);
508}
509
510static void
511serial_pxa_pm(struct uart_port *port, unsigned int state,
512 unsigned int oldstate)
513{
514 struct uart_pxa_port *up = (struct uart_pxa_port *)port;
515
516 if (!state)
517 clk_prepare_enable(up->clk);
518 else
519 clk_disable_unprepare(up->clk);
520}
521
522static void serial_pxa_release_port(struct uart_port *port)
523{
524}
525
526static int serial_pxa_request_port(struct uart_port *port)
527{
528 return 0;
529}
530
531static void serial_pxa_config_port(struct uart_port *port, int flags)
532{
533 struct uart_pxa_port *up = (struct uart_pxa_port *)port;
534 up->port.type = PORT_PXA;
535}
536
537static int
538serial_pxa_verify_port(struct uart_port *port, struct serial_struct *ser)
539{
540 /* we don't want the core code to modify any port params */
541 return -EINVAL;
542}
543
544static const char *
545serial_pxa_type(struct uart_port *port)
546{
547 struct uart_pxa_port *up = (struct uart_pxa_port *)port;
548 return up->name;
549}
550
551static struct uart_pxa_port *serial_pxa_ports[4];
552static struct uart_driver serial_pxa_reg;
553
554#ifdef CONFIG_SERIAL_PXA_CONSOLE
555
556/*
557 * Wait for transmitter & holding register to empty
558 */
559static void wait_for_xmitr(struct uart_pxa_port *up)
560{
561 unsigned int status, tmout = 10000;
562
563 /* Wait up to 10ms for the character(s) to be sent. */
564 do {
565 status = serial_in(up, UART_LSR);
566
567 if (status & UART_LSR_BI)
568 up->lsr_break_flag = UART_LSR_BI;
569
570 if (--tmout == 0)
571 break;
572 udelay(1);
573 } while (!uart_lsr_tx_empty(status));
574
575 /* Wait up to 1s for flow control if necessary */
576 if (up->port.flags & UPF_CONS_FLOW) {
577 tmout = 1000000;
578 while (--tmout &&
579 ((serial_in(up, UART_MSR) & UART_MSR_CTS) == 0))
580 udelay(1);
581 }
582}
583
584static void serial_pxa_console_putchar(struct uart_port *port, unsigned char ch)
585{
586 struct uart_pxa_port *up = (struct uart_pxa_port *)port;
587
588 wait_for_xmitr(up);
589 serial_out(up, UART_TX, ch);
590}
591
592/*
593 * Print a string to the serial port trying not to disturb
594 * any possible real use of the port...
595 *
596 * The console_lock must be held when we get here.
597 */
598static void
599serial_pxa_console_write(struct console *co, const char *s, unsigned int count)
600{
601 struct uart_pxa_port *up = serial_pxa_ports[co->index];
602 unsigned int ier;
603 unsigned long flags;
604 int locked = 1;
605
606 clk_enable(up->clk);
607 local_irq_save(flags);
608 if (up->port.sysrq)
609 locked = 0;
610 else if (oops_in_progress)
611 locked = uart_port_trylock(&up->port);
612 else
613 uart_port_lock(&up->port);
614
615 /*
616 * First save the IER then disable the interrupts
617 */
618 ier = serial_in(up, UART_IER);
619 serial_out(up, UART_IER, UART_IER_UUE);
620
621 uart_console_write(&up->port, s, count, serial_pxa_console_putchar);
622
623 /*
624 * Finally, wait for transmitter to become empty
625 * and restore the IER
626 */
627 wait_for_xmitr(up);
628 serial_out(up, UART_IER, ier);
629
630 if (locked)
631 uart_port_unlock(&up->port);
632 local_irq_restore(flags);
633 clk_disable(up->clk);
634
635}
636
637#ifdef CONFIG_CONSOLE_POLL
638/*
639 * Console polling routines for writing and reading from the uart while
640 * in an interrupt or debug context.
641 */
642
643static int serial_pxa_get_poll_char(struct uart_port *port)
644{
645 struct uart_pxa_port *up = (struct uart_pxa_port *)port;
646 unsigned char lsr = serial_in(up, UART_LSR);
647
648 while (!(lsr & UART_LSR_DR))
649 lsr = serial_in(up, UART_LSR);
650
651 return serial_in(up, UART_RX);
652}
653
654
655static void serial_pxa_put_poll_char(struct uart_port *port,
656 unsigned char c)
657{
658 unsigned int ier;
659 struct uart_pxa_port *up = (struct uart_pxa_port *)port;
660
661 /*
662 * First save the IER then disable the interrupts
663 */
664 ier = serial_in(up, UART_IER);
665 serial_out(up, UART_IER, UART_IER_UUE);
666
667 wait_for_xmitr(up);
668 /*
669 * Send the character out.
670 */
671 serial_out(up, UART_TX, c);
672
673 /*
674 * Finally, wait for transmitter to become empty
675 * and restore the IER
676 */
677 wait_for_xmitr(up);
678 serial_out(up, UART_IER, ier);
679}
680
681#endif /* CONFIG_CONSOLE_POLL */
682
683static int __init
684serial_pxa_console_setup(struct console *co, char *options)
685{
686 struct uart_pxa_port *up;
687 int baud = 9600;
688 int bits = 8;
689 int parity = 'n';
690 int flow = 'n';
691
692 if (co->index == -1 || co->index >= serial_pxa_reg.nr)
693 co->index = 0;
694 up = serial_pxa_ports[co->index];
695 if (!up)
696 return -ENODEV;
697
698 if (options)
699 uart_parse_options(options, &baud, &parity, &bits, &flow);
700
701 return uart_set_options(&up->port, co, baud, parity, bits, flow);
702}
703
704static struct console serial_pxa_console = {
705 .name = "ttyS",
706 .write = serial_pxa_console_write,
707 .device = uart_console_device,
708 .setup = serial_pxa_console_setup,
709 .flags = CON_PRINTBUFFER,
710 .index = -1,
711 .data = &serial_pxa_reg,
712};
713
714#define PXA_CONSOLE &serial_pxa_console
715#else
716#define PXA_CONSOLE NULL
717#endif
718
719static const struct uart_ops serial_pxa_pops = {
720 .tx_empty = serial_pxa_tx_empty,
721 .set_mctrl = serial_pxa_set_mctrl,
722 .get_mctrl = serial_pxa_get_mctrl,
723 .stop_tx = serial_pxa_stop_tx,
724 .start_tx = serial_pxa_start_tx,
725 .stop_rx = serial_pxa_stop_rx,
726 .enable_ms = serial_pxa_enable_ms,
727 .break_ctl = serial_pxa_break_ctl,
728 .startup = serial_pxa_startup,
729 .shutdown = serial_pxa_shutdown,
730 .set_termios = serial_pxa_set_termios,
731 .pm = serial_pxa_pm,
732 .type = serial_pxa_type,
733 .release_port = serial_pxa_release_port,
734 .request_port = serial_pxa_request_port,
735 .config_port = serial_pxa_config_port,
736 .verify_port = serial_pxa_verify_port,
737#if defined(CONFIG_CONSOLE_POLL) && defined(CONFIG_SERIAL_PXA_CONSOLE)
738 .poll_get_char = serial_pxa_get_poll_char,
739 .poll_put_char = serial_pxa_put_poll_char,
740#endif
741};
742
743static struct uart_driver serial_pxa_reg = {
744 .owner = THIS_MODULE,
745 .driver_name = "PXA serial",
746 .dev_name = "ttyS",
747 .major = TTY_MAJOR,
748 .minor = 64,
749 .nr = 4,
750 .cons = PXA_CONSOLE,
751};
752
753#ifdef CONFIG_PM
754static int serial_pxa_suspend(struct device *dev)
755{
756 struct uart_pxa_port *sport = dev_get_drvdata(dev);
757
758 if (sport)
759 uart_suspend_port(&serial_pxa_reg, &sport->port);
760
761 return 0;
762}
763
764static int serial_pxa_resume(struct device *dev)
765{
766 struct uart_pxa_port *sport = dev_get_drvdata(dev);
767
768 if (sport)
769 uart_resume_port(&serial_pxa_reg, &sport->port);
770
771 return 0;
772}
773
774static const struct dev_pm_ops serial_pxa_pm_ops = {
775 .suspend = serial_pxa_suspend,
776 .resume = serial_pxa_resume,
777};
778#endif
779
780static const struct of_device_id serial_pxa_dt_ids[] = {
781 { .compatible = "mrvl,pxa-uart", },
782 { .compatible = "mrvl,mmp-uart", },
783 {}
784};
785
786static int serial_pxa_probe_dt(struct platform_device *pdev,
787 struct uart_pxa_port *sport)
788{
789 struct device_node *np = pdev->dev.of_node;
790 int ret;
791
792 if (!np)
793 return 1;
794
795 ret = of_alias_get_id(np, "serial");
796 if (ret < 0) {
797 dev_err(&pdev->dev, "failed to get alias id, errno %d\n", ret);
798 return ret;
799 }
800 sport->port.line = ret;
801 return 0;
802}
803
804static int serial_pxa_probe(struct platform_device *dev)
805{
806 struct uart_pxa_port *sport;
807 struct resource *mmres;
808 int ret;
809 int irq;
810
811 mmres = platform_get_resource(dev, IORESOURCE_MEM, 0);
812 if (!mmres)
813 return -ENODEV;
814
815 irq = platform_get_irq(dev, 0);
816 if (irq < 0)
817 return irq;
818
819 sport = kzalloc(sizeof(struct uart_pxa_port), GFP_KERNEL);
820 if (!sport)
821 return -ENOMEM;
822
823 sport->clk = clk_get(&dev->dev, NULL);
824 if (IS_ERR(sport->clk)) {
825 ret = PTR_ERR(sport->clk);
826 goto err_free;
827 }
828
829 ret = clk_prepare(sport->clk);
830 if (ret) {
831 clk_put(sport->clk);
832 goto err_free;
833 }
834
835 sport->port.type = PORT_PXA;
836 sport->port.iotype = UPIO_MEM;
837 sport->port.mapbase = mmres->start;
838 sport->port.irq = irq;
839 sport->port.fifosize = 64;
840 sport->port.ops = &serial_pxa_pops;
841 sport->port.dev = &dev->dev;
842 sport->port.flags = UPF_IOREMAP | UPF_BOOT_AUTOCONF;
843 sport->port.uartclk = clk_get_rate(sport->clk);
844 sport->port.has_sysrq = IS_ENABLED(CONFIG_SERIAL_PXA_CONSOLE);
845
846 ret = serial_pxa_probe_dt(dev, sport);
847 if (ret > 0)
848 sport->port.line = dev->id;
849 else if (ret < 0)
850 goto err_clk;
851 if (sport->port.line >= ARRAY_SIZE(serial_pxa_ports)) {
852 dev_err(&dev->dev, "serial%d out of range\n", sport->port.line);
853 ret = -EINVAL;
854 goto err_clk;
855 }
856 snprintf(sport->name, PXA_NAME_LEN - 1, "UART%d", sport->port.line + 1);
857
858 sport->port.membase = ioremap(mmres->start, resource_size(mmres));
859 if (!sport->port.membase) {
860 ret = -ENOMEM;
861 goto err_clk;
862 }
863
864 serial_pxa_ports[sport->port.line] = sport;
865
866 uart_add_one_port(&serial_pxa_reg, &sport->port);
867 platform_set_drvdata(dev, sport);
868
869 return 0;
870
871 err_clk:
872 clk_unprepare(sport->clk);
873 clk_put(sport->clk);
874 err_free:
875 kfree(sport);
876 return ret;
877}
878
879static struct platform_driver serial_pxa_driver = {
880 .probe = serial_pxa_probe,
881
882 .driver = {
883 .name = "pxa2xx-uart",
884#ifdef CONFIG_PM
885 .pm = &serial_pxa_pm_ops,
886#endif
887 .suppress_bind_attrs = true,
888 .of_match_table = serial_pxa_dt_ids,
889 },
890};
891
892
893/* 8250 driver for PXA serial ports should be used */
894static int __init serial_pxa_init(void)
895{
896 int ret;
897
898 ret = uart_register_driver(&serial_pxa_reg);
899 if (ret != 0)
900 return ret;
901
902 ret = platform_driver_register(&serial_pxa_driver);
903 if (ret != 0)
904 uart_unregister_driver(&serial_pxa_reg);
905
906 return ret;
907}
908device_initcall(serial_pxa_init);
1/*
2 * Based on drivers/serial/8250.c by Russell King.
3 *
4 * Author: Nicolas Pitre
5 * Created: Feb 20, 2003
6 * Copyright: (C) 2003 Monta Vista Software, Inc.
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
12 *
13 * Note 1: This driver is made separate from the already too overloaded
14 * 8250.c because it needs some kirks of its own and that'll make it
15 * easier to add DMA support.
16 *
17 * Note 2: I'm too sick of device allocation policies for serial ports.
18 * If someone else wants to request an "official" allocation of major/minor
19 * for this driver please be my guest. And don't forget that new hardware
20 * to come from Intel might have more than 3 or 4 of those UARTs. Let's
21 * hope for a better port registration and dynamic device allocation scheme
22 * with the serial core maintainer satisfaction to appear soon.
23 */
24
25
26#if defined(CONFIG_SERIAL_PXA_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
27#define SUPPORT_SYSRQ
28#endif
29
30#include <linux/module.h>
31#include <linux/ioport.h>
32#include <linux/init.h>
33#include <linux/console.h>
34#include <linux/sysrq.h>
35#include <linux/serial_reg.h>
36#include <linux/circ_buf.h>
37#include <linux/delay.h>
38#include <linux/interrupt.h>
39#include <linux/of.h>
40#include <linux/platform_device.h>
41#include <linux/tty.h>
42#include <linux/tty_flip.h>
43#include <linux/serial_core.h>
44#include <linux/clk.h>
45#include <linux/io.h>
46#include <linux/slab.h>
47
48#define PXA_NAME_LEN 8
49
50struct uart_pxa_port {
51 struct uart_port port;
52 unsigned char ier;
53 unsigned char lcr;
54 unsigned char mcr;
55 unsigned int lsr_break_flag;
56 struct clk *clk;
57 char name[PXA_NAME_LEN];
58};
59
60static inline unsigned int serial_in(struct uart_pxa_port *up, int offset)
61{
62 offset <<= 2;
63 return readl(up->port.membase + offset);
64}
65
66static inline void serial_out(struct uart_pxa_port *up, int offset, int value)
67{
68 offset <<= 2;
69 writel(value, up->port.membase + offset);
70}
71
72static void serial_pxa_enable_ms(struct uart_port *port)
73{
74 struct uart_pxa_port *up = (struct uart_pxa_port *)port;
75
76 up->ier |= UART_IER_MSI;
77 serial_out(up, UART_IER, up->ier);
78}
79
80static void serial_pxa_stop_tx(struct uart_port *port)
81{
82 struct uart_pxa_port *up = (struct uart_pxa_port *)port;
83
84 if (up->ier & UART_IER_THRI) {
85 up->ier &= ~UART_IER_THRI;
86 serial_out(up, UART_IER, up->ier);
87 }
88}
89
90static void serial_pxa_stop_rx(struct uart_port *port)
91{
92 struct uart_pxa_port *up = (struct uart_pxa_port *)port;
93
94 up->ier &= ~UART_IER_RLSI;
95 up->port.read_status_mask &= ~UART_LSR_DR;
96 serial_out(up, UART_IER, up->ier);
97}
98
99static inline void receive_chars(struct uart_pxa_port *up, int *status)
100{
101 struct tty_struct *tty = up->port.state->port.tty;
102 unsigned int ch, flag;
103 int max_count = 256;
104
105 do {
106 /* work around Errata #20 according to
107 * Intel(R) PXA27x Processor Family
108 * Specification Update (May 2005)
109 *
110 * Step 2
111 * Disable the Reciever Time Out Interrupt via IER[RTOEI]
112 */
113 up->ier &= ~UART_IER_RTOIE;
114 serial_out(up, UART_IER, up->ier);
115
116 ch = serial_in(up, UART_RX);
117 flag = TTY_NORMAL;
118 up->port.icount.rx++;
119
120 if (unlikely(*status & (UART_LSR_BI | UART_LSR_PE |
121 UART_LSR_FE | UART_LSR_OE))) {
122 /*
123 * For statistics only
124 */
125 if (*status & UART_LSR_BI) {
126 *status &= ~(UART_LSR_FE | UART_LSR_PE);
127 up->port.icount.brk++;
128 /*
129 * We do the SysRQ and SAK checking
130 * here because otherwise the break
131 * may get masked by ignore_status_mask
132 * or read_status_mask.
133 */
134 if (uart_handle_break(&up->port))
135 goto ignore_char;
136 } else if (*status & UART_LSR_PE)
137 up->port.icount.parity++;
138 else if (*status & UART_LSR_FE)
139 up->port.icount.frame++;
140 if (*status & UART_LSR_OE)
141 up->port.icount.overrun++;
142
143 /*
144 * Mask off conditions which should be ignored.
145 */
146 *status &= up->port.read_status_mask;
147
148#ifdef CONFIG_SERIAL_PXA_CONSOLE
149 if (up->port.line == up->port.cons->index) {
150 /* Recover the break flag from console xmit */
151 *status |= up->lsr_break_flag;
152 up->lsr_break_flag = 0;
153 }
154#endif
155 if (*status & UART_LSR_BI) {
156 flag = TTY_BREAK;
157 } else if (*status & UART_LSR_PE)
158 flag = TTY_PARITY;
159 else if (*status & UART_LSR_FE)
160 flag = TTY_FRAME;
161 }
162
163 if (uart_handle_sysrq_char(&up->port, ch))
164 goto ignore_char;
165
166 uart_insert_char(&up->port, *status, UART_LSR_OE, ch, flag);
167
168 ignore_char:
169 *status = serial_in(up, UART_LSR);
170 } while ((*status & UART_LSR_DR) && (max_count-- > 0));
171 tty_flip_buffer_push(tty);
172
173 /* work around Errata #20 according to
174 * Intel(R) PXA27x Processor Family
175 * Specification Update (May 2005)
176 *
177 * Step 6:
178 * No more data in FIFO: Re-enable RTO interrupt via IER[RTOIE]
179 */
180 up->ier |= UART_IER_RTOIE;
181 serial_out(up, UART_IER, up->ier);
182}
183
184static void transmit_chars(struct uart_pxa_port *up)
185{
186 struct circ_buf *xmit = &up->port.state->xmit;
187 int count;
188
189 if (up->port.x_char) {
190 serial_out(up, UART_TX, up->port.x_char);
191 up->port.icount.tx++;
192 up->port.x_char = 0;
193 return;
194 }
195 if (uart_circ_empty(xmit) || uart_tx_stopped(&up->port)) {
196 serial_pxa_stop_tx(&up->port);
197 return;
198 }
199
200 count = up->port.fifosize / 2;
201 do {
202 serial_out(up, UART_TX, xmit->buf[xmit->tail]);
203 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
204 up->port.icount.tx++;
205 if (uart_circ_empty(xmit))
206 break;
207 } while (--count > 0);
208
209 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
210 uart_write_wakeup(&up->port);
211
212
213 if (uart_circ_empty(xmit))
214 serial_pxa_stop_tx(&up->port);
215}
216
217static void serial_pxa_start_tx(struct uart_port *port)
218{
219 struct uart_pxa_port *up = (struct uart_pxa_port *)port;
220
221 if (!(up->ier & UART_IER_THRI)) {
222 up->ier |= UART_IER_THRI;
223 serial_out(up, UART_IER, up->ier);
224 }
225}
226
227static inline void check_modem_status(struct uart_pxa_port *up)
228{
229 int status;
230
231 status = serial_in(up, UART_MSR);
232
233 if ((status & UART_MSR_ANY_DELTA) == 0)
234 return;
235
236 if (status & UART_MSR_TERI)
237 up->port.icount.rng++;
238 if (status & UART_MSR_DDSR)
239 up->port.icount.dsr++;
240 if (status & UART_MSR_DDCD)
241 uart_handle_dcd_change(&up->port, status & UART_MSR_DCD);
242 if (status & UART_MSR_DCTS)
243 uart_handle_cts_change(&up->port, status & UART_MSR_CTS);
244
245 wake_up_interruptible(&up->port.state->port.delta_msr_wait);
246}
247
248/*
249 * This handles the interrupt from one port.
250 */
251static inline irqreturn_t serial_pxa_irq(int irq, void *dev_id)
252{
253 struct uart_pxa_port *up = dev_id;
254 unsigned int iir, lsr;
255
256 iir = serial_in(up, UART_IIR);
257 if (iir & UART_IIR_NO_INT)
258 return IRQ_NONE;
259 lsr = serial_in(up, UART_LSR);
260 if (lsr & UART_LSR_DR)
261 receive_chars(up, &lsr);
262 check_modem_status(up);
263 if (lsr & UART_LSR_THRE)
264 transmit_chars(up);
265 return IRQ_HANDLED;
266}
267
268static unsigned int serial_pxa_tx_empty(struct uart_port *port)
269{
270 struct uart_pxa_port *up = (struct uart_pxa_port *)port;
271 unsigned long flags;
272 unsigned int ret;
273
274 spin_lock_irqsave(&up->port.lock, flags);
275 ret = serial_in(up, UART_LSR) & UART_LSR_TEMT ? TIOCSER_TEMT : 0;
276 spin_unlock_irqrestore(&up->port.lock, flags);
277
278 return ret;
279}
280
281static unsigned int serial_pxa_get_mctrl(struct uart_port *port)
282{
283 struct uart_pxa_port *up = (struct uart_pxa_port *)port;
284 unsigned char status;
285 unsigned int ret;
286
287 status = serial_in(up, UART_MSR);
288
289 ret = 0;
290 if (status & UART_MSR_DCD)
291 ret |= TIOCM_CAR;
292 if (status & UART_MSR_RI)
293 ret |= TIOCM_RNG;
294 if (status & UART_MSR_DSR)
295 ret |= TIOCM_DSR;
296 if (status & UART_MSR_CTS)
297 ret |= TIOCM_CTS;
298 return ret;
299}
300
301static void serial_pxa_set_mctrl(struct uart_port *port, unsigned int mctrl)
302{
303 struct uart_pxa_port *up = (struct uart_pxa_port *)port;
304 unsigned char mcr = 0;
305
306 if (mctrl & TIOCM_RTS)
307 mcr |= UART_MCR_RTS;
308 if (mctrl & TIOCM_DTR)
309 mcr |= UART_MCR_DTR;
310 if (mctrl & TIOCM_OUT1)
311 mcr |= UART_MCR_OUT1;
312 if (mctrl & TIOCM_OUT2)
313 mcr |= UART_MCR_OUT2;
314 if (mctrl & TIOCM_LOOP)
315 mcr |= UART_MCR_LOOP;
316
317 mcr |= up->mcr;
318
319 serial_out(up, UART_MCR, mcr);
320}
321
322static void serial_pxa_break_ctl(struct uart_port *port, int break_state)
323{
324 struct uart_pxa_port *up = (struct uart_pxa_port *)port;
325 unsigned long flags;
326
327 spin_lock_irqsave(&up->port.lock, flags);
328 if (break_state == -1)
329 up->lcr |= UART_LCR_SBC;
330 else
331 up->lcr &= ~UART_LCR_SBC;
332 serial_out(up, UART_LCR, up->lcr);
333 spin_unlock_irqrestore(&up->port.lock, flags);
334}
335
336#if 0
337static void serial_pxa_dma_init(struct pxa_uart *up)
338{
339 up->rxdma =
340 pxa_request_dma(up->name, DMA_PRIO_LOW, pxa_receive_dma, up);
341 if (up->rxdma < 0)
342 goto out;
343 up->txdma =
344 pxa_request_dma(up->name, DMA_PRIO_LOW, pxa_transmit_dma, up);
345 if (up->txdma < 0)
346 goto err_txdma;
347 up->dmadesc = kmalloc(4 * sizeof(pxa_dma_desc), GFP_KERNEL);
348 if (!up->dmadesc)
349 goto err_alloc;
350
351 /* ... */
352err_alloc:
353 pxa_free_dma(up->txdma);
354err_rxdma:
355 pxa_free_dma(up->rxdma);
356out:
357 return;
358}
359#endif
360
361static int serial_pxa_startup(struct uart_port *port)
362{
363 struct uart_pxa_port *up = (struct uart_pxa_port *)port;
364 unsigned long flags;
365 int retval;
366
367 if (port->line == 3) /* HWUART */
368 up->mcr |= UART_MCR_AFE;
369 else
370 up->mcr = 0;
371
372 up->port.uartclk = clk_get_rate(up->clk);
373
374 /*
375 * Allocate the IRQ
376 */
377 retval = request_irq(up->port.irq, serial_pxa_irq, 0, up->name, up);
378 if (retval)
379 return retval;
380
381 /*
382 * Clear the FIFO buffers and disable them.
383 * (they will be reenabled in set_termios())
384 */
385 serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO);
386 serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO |
387 UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT);
388 serial_out(up, UART_FCR, 0);
389
390 /*
391 * Clear the interrupt registers.
392 */
393 (void) serial_in(up, UART_LSR);
394 (void) serial_in(up, UART_RX);
395 (void) serial_in(up, UART_IIR);
396 (void) serial_in(up, UART_MSR);
397
398 /*
399 * Now, initialize the UART
400 */
401 serial_out(up, UART_LCR, UART_LCR_WLEN8);
402
403 spin_lock_irqsave(&up->port.lock, flags);
404 up->port.mctrl |= TIOCM_OUT2;
405 serial_pxa_set_mctrl(&up->port, up->port.mctrl);
406 spin_unlock_irqrestore(&up->port.lock, flags);
407
408 /*
409 * Finally, enable interrupts. Note: Modem status interrupts
410 * are set via set_termios(), which will be occurring imminently
411 * anyway, so we don't enable them here.
412 */
413 up->ier = UART_IER_RLSI | UART_IER_RDI | UART_IER_RTOIE | UART_IER_UUE;
414 serial_out(up, UART_IER, up->ier);
415
416 /*
417 * And clear the interrupt registers again for luck.
418 */
419 (void) serial_in(up, UART_LSR);
420 (void) serial_in(up, UART_RX);
421 (void) serial_in(up, UART_IIR);
422 (void) serial_in(up, UART_MSR);
423
424 return 0;
425}
426
427static void serial_pxa_shutdown(struct uart_port *port)
428{
429 struct uart_pxa_port *up = (struct uart_pxa_port *)port;
430 unsigned long flags;
431
432 free_irq(up->port.irq, up);
433
434 /*
435 * Disable interrupts from this port
436 */
437 up->ier = 0;
438 serial_out(up, UART_IER, 0);
439
440 spin_lock_irqsave(&up->port.lock, flags);
441 up->port.mctrl &= ~TIOCM_OUT2;
442 serial_pxa_set_mctrl(&up->port, up->port.mctrl);
443 spin_unlock_irqrestore(&up->port.lock, flags);
444
445 /*
446 * Disable break condition and FIFOs
447 */
448 serial_out(up, UART_LCR, serial_in(up, UART_LCR) & ~UART_LCR_SBC);
449 serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO |
450 UART_FCR_CLEAR_RCVR |
451 UART_FCR_CLEAR_XMIT);
452 serial_out(up, UART_FCR, 0);
453}
454
455static void
456serial_pxa_set_termios(struct uart_port *port, struct ktermios *termios,
457 struct ktermios *old)
458{
459 struct uart_pxa_port *up = (struct uart_pxa_port *)port;
460 unsigned char cval, fcr = 0;
461 unsigned long flags;
462 unsigned int baud, quot;
463 unsigned int dll;
464
465 switch (termios->c_cflag & CSIZE) {
466 case CS5:
467 cval = UART_LCR_WLEN5;
468 break;
469 case CS6:
470 cval = UART_LCR_WLEN6;
471 break;
472 case CS7:
473 cval = UART_LCR_WLEN7;
474 break;
475 default:
476 case CS8:
477 cval = UART_LCR_WLEN8;
478 break;
479 }
480
481 if (termios->c_cflag & CSTOPB)
482 cval |= UART_LCR_STOP;
483 if (termios->c_cflag & PARENB)
484 cval |= UART_LCR_PARITY;
485 if (!(termios->c_cflag & PARODD))
486 cval |= UART_LCR_EPAR;
487
488 /*
489 * Ask the core to calculate the divisor for us.
490 */
491 baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk/16);
492 quot = uart_get_divisor(port, baud);
493
494 if ((up->port.uartclk / quot) < (2400 * 16))
495 fcr = UART_FCR_ENABLE_FIFO | UART_FCR_PXAR1;
496 else if ((up->port.uartclk / quot) < (230400 * 16))
497 fcr = UART_FCR_ENABLE_FIFO | UART_FCR_PXAR8;
498 else
499 fcr = UART_FCR_ENABLE_FIFO | UART_FCR_PXAR32;
500
501 /*
502 * Ok, we're now changing the port state. Do it with
503 * interrupts disabled.
504 */
505 spin_lock_irqsave(&up->port.lock, flags);
506
507 /*
508 * Ensure the port will be enabled.
509 * This is required especially for serial console.
510 */
511 up->ier |= UART_IER_UUE;
512
513 /*
514 * Update the per-port timeout.
515 */
516 uart_update_timeout(port, termios->c_cflag, baud);
517
518 up->port.read_status_mask = UART_LSR_OE | UART_LSR_THRE | UART_LSR_DR;
519 if (termios->c_iflag & INPCK)
520 up->port.read_status_mask |= UART_LSR_FE | UART_LSR_PE;
521 if (termios->c_iflag & (BRKINT | PARMRK))
522 up->port.read_status_mask |= UART_LSR_BI;
523
524 /*
525 * Characters to ignore
526 */
527 up->port.ignore_status_mask = 0;
528 if (termios->c_iflag & IGNPAR)
529 up->port.ignore_status_mask |= UART_LSR_PE | UART_LSR_FE;
530 if (termios->c_iflag & IGNBRK) {
531 up->port.ignore_status_mask |= UART_LSR_BI;
532 /*
533 * If we're ignoring parity and break indicators,
534 * ignore overruns too (for real raw support).
535 */
536 if (termios->c_iflag & IGNPAR)
537 up->port.ignore_status_mask |= UART_LSR_OE;
538 }
539
540 /*
541 * ignore all characters if CREAD is not set
542 */
543 if ((termios->c_cflag & CREAD) == 0)
544 up->port.ignore_status_mask |= UART_LSR_DR;
545
546 /*
547 * CTS flow control flag and modem status interrupts
548 */
549 up->ier &= ~UART_IER_MSI;
550 if (UART_ENABLE_MS(&up->port, termios->c_cflag))
551 up->ier |= UART_IER_MSI;
552
553 serial_out(up, UART_IER, up->ier);
554
555 if (termios->c_cflag & CRTSCTS)
556 up->mcr |= UART_MCR_AFE;
557 else
558 up->mcr &= ~UART_MCR_AFE;
559
560 serial_out(up, UART_LCR, cval | UART_LCR_DLAB); /* set DLAB */
561 serial_out(up, UART_DLL, quot & 0xff); /* LS of divisor */
562
563 /*
564 * work around Errata #75 according to Intel(R) PXA27x Processor Family
565 * Specification Update (Nov 2005)
566 */
567 dll = serial_in(up, UART_DLL);
568 WARN_ON(dll != (quot & 0xff));
569
570 serial_out(up, UART_DLM, quot >> 8); /* MS of divisor */
571 serial_out(up, UART_LCR, cval); /* reset DLAB */
572 up->lcr = cval; /* Save LCR */
573 serial_pxa_set_mctrl(&up->port, up->port.mctrl);
574 serial_out(up, UART_FCR, fcr);
575 spin_unlock_irqrestore(&up->port.lock, flags);
576}
577
578static void
579serial_pxa_pm(struct uart_port *port, unsigned int state,
580 unsigned int oldstate)
581{
582 struct uart_pxa_port *up = (struct uart_pxa_port *)port;
583
584 if (!state)
585 clk_prepare_enable(up->clk);
586 else
587 clk_disable_unprepare(up->clk);
588}
589
590static void serial_pxa_release_port(struct uart_port *port)
591{
592}
593
594static int serial_pxa_request_port(struct uart_port *port)
595{
596 return 0;
597}
598
599static void serial_pxa_config_port(struct uart_port *port, int flags)
600{
601 struct uart_pxa_port *up = (struct uart_pxa_port *)port;
602 up->port.type = PORT_PXA;
603}
604
605static int
606serial_pxa_verify_port(struct uart_port *port, struct serial_struct *ser)
607{
608 /* we don't want the core code to modify any port params */
609 return -EINVAL;
610}
611
612static const char *
613serial_pxa_type(struct uart_port *port)
614{
615 struct uart_pxa_port *up = (struct uart_pxa_port *)port;
616 return up->name;
617}
618
619static struct uart_pxa_port *serial_pxa_ports[4];
620static struct uart_driver serial_pxa_reg;
621
622#ifdef CONFIG_SERIAL_PXA_CONSOLE
623
624#define BOTH_EMPTY (UART_LSR_TEMT | UART_LSR_THRE)
625
626/*
627 * Wait for transmitter & holding register to empty
628 */
629static inline void wait_for_xmitr(struct uart_pxa_port *up)
630{
631 unsigned int status, tmout = 10000;
632
633 /* Wait up to 10ms for the character(s) to be sent. */
634 do {
635 status = serial_in(up, UART_LSR);
636
637 if (status & UART_LSR_BI)
638 up->lsr_break_flag = UART_LSR_BI;
639
640 if (--tmout == 0)
641 break;
642 udelay(1);
643 } while ((status & BOTH_EMPTY) != BOTH_EMPTY);
644
645 /* Wait up to 1s for flow control if necessary */
646 if (up->port.flags & UPF_CONS_FLOW) {
647 tmout = 1000000;
648 while (--tmout &&
649 ((serial_in(up, UART_MSR) & UART_MSR_CTS) == 0))
650 udelay(1);
651 }
652}
653
654static void serial_pxa_console_putchar(struct uart_port *port, int ch)
655{
656 struct uart_pxa_port *up = (struct uart_pxa_port *)port;
657
658 wait_for_xmitr(up);
659 serial_out(up, UART_TX, ch);
660}
661
662/*
663 * Print a string to the serial port trying not to disturb
664 * any possible real use of the port...
665 *
666 * The console_lock must be held when we get here.
667 */
668static void
669serial_pxa_console_write(struct console *co, const char *s, unsigned int count)
670{
671 struct uart_pxa_port *up = serial_pxa_ports[co->index];
672 unsigned int ier;
673
674 clk_prepare_enable(up->clk);
675
676 /*
677 * First save the IER then disable the interrupts
678 */
679 ier = serial_in(up, UART_IER);
680 serial_out(up, UART_IER, UART_IER_UUE);
681
682 uart_console_write(&up->port, s, count, serial_pxa_console_putchar);
683
684 /*
685 * Finally, wait for transmitter to become empty
686 * and restore the IER
687 */
688 wait_for_xmitr(up);
689 serial_out(up, UART_IER, ier);
690
691 clk_disable_unprepare(up->clk);
692}
693
694static int __init
695serial_pxa_console_setup(struct console *co, char *options)
696{
697 struct uart_pxa_port *up;
698 int baud = 9600;
699 int bits = 8;
700 int parity = 'n';
701 int flow = 'n';
702
703 if (co->index == -1 || co->index >= serial_pxa_reg.nr)
704 co->index = 0;
705 up = serial_pxa_ports[co->index];
706 if (!up)
707 return -ENODEV;
708
709 if (options)
710 uart_parse_options(options, &baud, &parity, &bits, &flow);
711
712 return uart_set_options(&up->port, co, baud, parity, bits, flow);
713}
714
715static struct console serial_pxa_console = {
716 .name = "ttyS",
717 .write = serial_pxa_console_write,
718 .device = uart_console_device,
719 .setup = serial_pxa_console_setup,
720 .flags = CON_PRINTBUFFER,
721 .index = -1,
722 .data = &serial_pxa_reg,
723};
724
725#define PXA_CONSOLE &serial_pxa_console
726#else
727#define PXA_CONSOLE NULL
728#endif
729
730struct uart_ops serial_pxa_pops = {
731 .tx_empty = serial_pxa_tx_empty,
732 .set_mctrl = serial_pxa_set_mctrl,
733 .get_mctrl = serial_pxa_get_mctrl,
734 .stop_tx = serial_pxa_stop_tx,
735 .start_tx = serial_pxa_start_tx,
736 .stop_rx = serial_pxa_stop_rx,
737 .enable_ms = serial_pxa_enable_ms,
738 .break_ctl = serial_pxa_break_ctl,
739 .startup = serial_pxa_startup,
740 .shutdown = serial_pxa_shutdown,
741 .set_termios = serial_pxa_set_termios,
742 .pm = serial_pxa_pm,
743 .type = serial_pxa_type,
744 .release_port = serial_pxa_release_port,
745 .request_port = serial_pxa_request_port,
746 .config_port = serial_pxa_config_port,
747 .verify_port = serial_pxa_verify_port,
748};
749
750static struct uart_driver serial_pxa_reg = {
751 .owner = THIS_MODULE,
752 .driver_name = "PXA serial",
753 .dev_name = "ttyS",
754 .major = TTY_MAJOR,
755 .minor = 64,
756 .nr = 4,
757 .cons = PXA_CONSOLE,
758};
759
760#ifdef CONFIG_PM
761static int serial_pxa_suspend(struct device *dev)
762{
763 struct uart_pxa_port *sport = dev_get_drvdata(dev);
764
765 if (sport)
766 uart_suspend_port(&serial_pxa_reg, &sport->port);
767
768 return 0;
769}
770
771static int serial_pxa_resume(struct device *dev)
772{
773 struct uart_pxa_port *sport = dev_get_drvdata(dev);
774
775 if (sport)
776 uart_resume_port(&serial_pxa_reg, &sport->port);
777
778 return 0;
779}
780
781static const struct dev_pm_ops serial_pxa_pm_ops = {
782 .suspend = serial_pxa_suspend,
783 .resume = serial_pxa_resume,
784};
785#endif
786
787static struct of_device_id serial_pxa_dt_ids[] = {
788 { .compatible = "mrvl,pxa-uart", },
789 { .compatible = "mrvl,mmp-uart", },
790 {}
791};
792MODULE_DEVICE_TABLE(of, serial_pxa_dt_ids);
793
794static int serial_pxa_probe_dt(struct platform_device *pdev,
795 struct uart_pxa_port *sport)
796{
797 struct device_node *np = pdev->dev.of_node;
798 int ret;
799
800 if (!np)
801 return 1;
802
803 ret = of_alias_get_id(np, "serial");
804 if (ret < 0) {
805 dev_err(&pdev->dev, "failed to get alias id, errno %d\n", ret);
806 return ret;
807 }
808 sport->port.line = ret;
809 return 0;
810}
811
812static int serial_pxa_probe(struct platform_device *dev)
813{
814 struct uart_pxa_port *sport;
815 struct resource *mmres, *irqres;
816 int ret;
817
818 mmres = platform_get_resource(dev, IORESOURCE_MEM, 0);
819 irqres = platform_get_resource(dev, IORESOURCE_IRQ, 0);
820 if (!mmres || !irqres)
821 return -ENODEV;
822
823 sport = kzalloc(sizeof(struct uart_pxa_port), GFP_KERNEL);
824 if (!sport)
825 return -ENOMEM;
826
827 sport->clk = clk_get(&dev->dev, NULL);
828 if (IS_ERR(sport->clk)) {
829 ret = PTR_ERR(sport->clk);
830 goto err_free;
831 }
832
833 sport->port.type = PORT_PXA;
834 sport->port.iotype = UPIO_MEM;
835 sport->port.mapbase = mmres->start;
836 sport->port.irq = irqres->start;
837 sport->port.fifosize = 64;
838 sport->port.ops = &serial_pxa_pops;
839 sport->port.dev = &dev->dev;
840 sport->port.flags = UPF_IOREMAP | UPF_BOOT_AUTOCONF;
841 sport->port.uartclk = clk_get_rate(sport->clk);
842
843 ret = serial_pxa_probe_dt(dev, sport);
844 if (ret > 0)
845 sport->port.line = dev->id;
846 else if (ret < 0)
847 goto err_clk;
848 snprintf(sport->name, PXA_NAME_LEN - 1, "UART%d", sport->port.line + 1);
849
850 sport->port.membase = ioremap(mmres->start, resource_size(mmres));
851 if (!sport->port.membase) {
852 ret = -ENOMEM;
853 goto err_clk;
854 }
855
856 serial_pxa_ports[sport->port.line] = sport;
857
858 uart_add_one_port(&serial_pxa_reg, &sport->port);
859 platform_set_drvdata(dev, sport);
860
861 return 0;
862
863 err_clk:
864 clk_put(sport->clk);
865 err_free:
866 kfree(sport);
867 return ret;
868}
869
870static int serial_pxa_remove(struct platform_device *dev)
871{
872 struct uart_pxa_port *sport = platform_get_drvdata(dev);
873
874 platform_set_drvdata(dev, NULL);
875
876 uart_remove_one_port(&serial_pxa_reg, &sport->port);
877 clk_put(sport->clk);
878 kfree(sport);
879
880 return 0;
881}
882
883static struct platform_driver serial_pxa_driver = {
884 .probe = serial_pxa_probe,
885 .remove = serial_pxa_remove,
886
887 .driver = {
888 .name = "pxa2xx-uart",
889 .owner = THIS_MODULE,
890#ifdef CONFIG_PM
891 .pm = &serial_pxa_pm_ops,
892#endif
893 .of_match_table = serial_pxa_dt_ids,
894 },
895};
896
897int __init serial_pxa_init(void)
898{
899 int ret;
900
901 ret = uart_register_driver(&serial_pxa_reg);
902 if (ret != 0)
903 return ret;
904
905 ret = platform_driver_register(&serial_pxa_driver);
906 if (ret != 0)
907 uart_unregister_driver(&serial_pxa_reg);
908
909 return ret;
910}
911
912void __exit serial_pxa_exit(void)
913{
914 platform_driver_unregister(&serial_pxa_driver);
915 uart_unregister_driver(&serial_pxa_reg);
916}
917
918module_init(serial_pxa_init);
919module_exit(serial_pxa_exit);
920
921MODULE_LICENSE("GPL");
922MODULE_ALIAS("platform:pxa2xx-uart");