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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// 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#if defined(CONFIG_SERIAL_PXA_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
23#define SUPPORT_SYSRQ
24#endif
25
26#include <linux/ioport.h>
27#include <linux/init.h>
28#include <linux/console.h>
29#include <linux/sysrq.h>
30#include <linux/serial_reg.h>
31#include <linux/circ_buf.h>
32#include <linux/delay.h>
33#include <linux/interrupt.h>
34#include <linux/of.h>
35#include <linux/platform_device.h>
36#include <linux/tty.h>
37#include <linux/tty_flip.h>
38#include <linux/serial_core.h>
39#include <linux/clk.h>
40#include <linux/io.h>
41#include <linux/slab.h>
42
43#define PXA_NAME_LEN 8
44
45struct uart_pxa_port {
46 struct uart_port port;
47 unsigned char ier;
48 unsigned char lcr;
49 unsigned char mcr;
50 unsigned int lsr_break_flag;
51 struct clk *clk;
52 char name[PXA_NAME_LEN];
53};
54
55static inline unsigned int serial_in(struct uart_pxa_port *up, int offset)
56{
57 offset <<= 2;
58 return readl(up->port.membase + offset);
59}
60
61static inline void serial_out(struct uart_pxa_port *up, int offset, int value)
62{
63 offset <<= 2;
64 writel(value, up->port.membase + offset);
65}
66
67static void serial_pxa_enable_ms(struct uart_port *port)
68{
69 struct uart_pxa_port *up = (struct uart_pxa_port *)port;
70
71 up->ier |= UART_IER_MSI;
72 serial_out(up, UART_IER, up->ier);
73}
74
75static void serial_pxa_stop_tx(struct uart_port *port)
76{
77 struct uart_pxa_port *up = (struct uart_pxa_port *)port;
78
79 if (up->ier & UART_IER_THRI) {
80 up->ier &= ~UART_IER_THRI;
81 serial_out(up, UART_IER, up->ier);
82 }
83}
84
85static void serial_pxa_stop_rx(struct uart_port *port)
86{
87 struct uart_pxa_port *up = (struct uart_pxa_port *)port;
88
89 up->ier &= ~UART_IER_RLSI;
90 up->port.read_status_mask &= ~UART_LSR_DR;
91 serial_out(up, UART_IER, up->ier);
92}
93
94static inline void receive_chars(struct uart_pxa_port *up, int *status)
95{
96 unsigned int ch, flag;
97 int max_count = 256;
98
99 do {
100 /* work around Errata #20 according to
101 * Intel(R) PXA27x Processor Family
102 * Specification Update (May 2005)
103 *
104 * Step 2
105 * Disable the Reciever Time Out Interrupt via IER[RTOEI]
106 */
107 up->ier &= ~UART_IER_RTOIE;
108 serial_out(up, UART_IER, up->ier);
109
110 ch = serial_in(up, UART_RX);
111 flag = TTY_NORMAL;
112 up->port.icount.rx++;
113
114 if (unlikely(*status & (UART_LSR_BI | UART_LSR_PE |
115 UART_LSR_FE | UART_LSR_OE))) {
116 /*
117 * For statistics only
118 */
119 if (*status & UART_LSR_BI) {
120 *status &= ~(UART_LSR_FE | UART_LSR_PE);
121 up->port.icount.brk++;
122 /*
123 * We do the SysRQ and SAK checking
124 * here because otherwise the break
125 * may get masked by ignore_status_mask
126 * or read_status_mask.
127 */
128 if (uart_handle_break(&up->port))
129 goto ignore_char;
130 } else if (*status & UART_LSR_PE)
131 up->port.icount.parity++;
132 else if (*status & UART_LSR_FE)
133 up->port.icount.frame++;
134 if (*status & UART_LSR_OE)
135 up->port.icount.overrun++;
136
137 /*
138 * Mask off conditions which should be ignored.
139 */
140 *status &= up->port.read_status_mask;
141
142#ifdef CONFIG_SERIAL_PXA_CONSOLE
143 if (up->port.line == up->port.cons->index) {
144 /* Recover the break flag from console xmit */
145 *status |= up->lsr_break_flag;
146 up->lsr_break_flag = 0;
147 }
148#endif
149 if (*status & UART_LSR_BI) {
150 flag = TTY_BREAK;
151 } else if (*status & UART_LSR_PE)
152 flag = TTY_PARITY;
153 else if (*status & UART_LSR_FE)
154 flag = TTY_FRAME;
155 }
156
157 if (uart_handle_sysrq_char(&up->port, ch))
158 goto ignore_char;
159
160 uart_insert_char(&up->port, *status, UART_LSR_OE, ch, flag);
161
162 ignore_char:
163 *status = serial_in(up, UART_LSR);
164 } while ((*status & UART_LSR_DR) && (max_count-- > 0));
165 tty_flip_buffer_push(&up->port.state->port);
166
167 /* work around Errata #20 according to
168 * Intel(R) PXA27x Processor Family
169 * Specification Update (May 2005)
170 *
171 * Step 6:
172 * No more data in FIFO: Re-enable RTO interrupt via IER[RTOIE]
173 */
174 up->ier |= UART_IER_RTOIE;
175 serial_out(up, UART_IER, up->ier);
176}
177
178static void transmit_chars(struct uart_pxa_port *up)
179{
180 struct circ_buf *xmit = &up->port.state->xmit;
181 int count;
182
183 if (up->port.x_char) {
184 serial_out(up, UART_TX, up->port.x_char);
185 up->port.icount.tx++;
186 up->port.x_char = 0;
187 return;
188 }
189 if (uart_circ_empty(xmit) || uart_tx_stopped(&up->port)) {
190 serial_pxa_stop_tx(&up->port);
191 return;
192 }
193
194 count = up->port.fifosize / 2;
195 do {
196 serial_out(up, UART_TX, xmit->buf[xmit->tail]);
197 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
198 up->port.icount.tx++;
199 if (uart_circ_empty(xmit))
200 break;
201 } while (--count > 0);
202
203 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
204 uart_write_wakeup(&up->port);
205
206
207 if (uart_circ_empty(xmit))
208 serial_pxa_stop_tx(&up->port);
209}
210
211static void serial_pxa_start_tx(struct uart_port *port)
212{
213 struct uart_pxa_port *up = (struct uart_pxa_port *)port;
214
215 if (!(up->ier & UART_IER_THRI)) {
216 up->ier |= UART_IER_THRI;
217 serial_out(up, UART_IER, up->ier);
218 }
219}
220
221/* should hold up->port.lock */
222static inline void check_modem_status(struct uart_pxa_port *up)
223{
224 int status;
225
226 status = serial_in(up, UART_MSR);
227
228 if ((status & UART_MSR_ANY_DELTA) == 0)
229 return;
230
231 if (status & UART_MSR_TERI)
232 up->port.icount.rng++;
233 if (status & UART_MSR_DDSR)
234 up->port.icount.dsr++;
235 if (status & UART_MSR_DDCD)
236 uart_handle_dcd_change(&up->port, status & UART_MSR_DCD);
237 if (status & UART_MSR_DCTS)
238 uart_handle_cts_change(&up->port, status & UART_MSR_CTS);
239
240 wake_up_interruptible(&up->port.state->port.delta_msr_wait);
241}
242
243/*
244 * This handles the interrupt from one port.
245 */
246static inline irqreturn_t serial_pxa_irq(int irq, void *dev_id)
247{
248 struct uart_pxa_port *up = dev_id;
249 unsigned int iir, lsr;
250
251 iir = serial_in(up, UART_IIR);
252 if (iir & UART_IIR_NO_INT)
253 return IRQ_NONE;
254 spin_lock(&up->port.lock);
255 lsr = serial_in(up, UART_LSR);
256 if (lsr & UART_LSR_DR)
257 receive_chars(up, &lsr);
258 check_modem_status(up);
259 if (lsr & UART_LSR_THRE)
260 transmit_chars(up);
261 spin_unlock(&up->port.lock);
262 return IRQ_HANDLED;
263}
264
265static unsigned int serial_pxa_tx_empty(struct uart_port *port)
266{
267 struct uart_pxa_port *up = (struct uart_pxa_port *)port;
268 unsigned long flags;
269 unsigned int ret;
270
271 spin_lock_irqsave(&up->port.lock, flags);
272 ret = serial_in(up, UART_LSR) & UART_LSR_TEMT ? TIOCSER_TEMT : 0;
273 spin_unlock_irqrestore(&up->port.lock, flags);
274
275 return ret;
276}
277
278static unsigned int serial_pxa_get_mctrl(struct uart_port *port)
279{
280 struct uart_pxa_port *up = (struct uart_pxa_port *)port;
281 unsigned char status;
282 unsigned int ret;
283
284 status = serial_in(up, UART_MSR);
285
286 ret = 0;
287 if (status & UART_MSR_DCD)
288 ret |= TIOCM_CAR;
289 if (status & UART_MSR_RI)
290 ret |= TIOCM_RNG;
291 if (status & UART_MSR_DSR)
292 ret |= TIOCM_DSR;
293 if (status & UART_MSR_CTS)
294 ret |= TIOCM_CTS;
295 return ret;
296}
297
298static void serial_pxa_set_mctrl(struct uart_port *port, unsigned int mctrl)
299{
300 struct uart_pxa_port *up = (struct uart_pxa_port *)port;
301 unsigned char mcr = 0;
302
303 if (mctrl & TIOCM_RTS)
304 mcr |= UART_MCR_RTS;
305 if (mctrl & TIOCM_DTR)
306 mcr |= UART_MCR_DTR;
307 if (mctrl & TIOCM_OUT1)
308 mcr |= UART_MCR_OUT1;
309 if (mctrl & TIOCM_OUT2)
310 mcr |= UART_MCR_OUT2;
311 if (mctrl & TIOCM_LOOP)
312 mcr |= UART_MCR_LOOP;
313
314 mcr |= up->mcr;
315
316 serial_out(up, UART_MCR, mcr);
317}
318
319static void serial_pxa_break_ctl(struct uart_port *port, int break_state)
320{
321 struct uart_pxa_port *up = (struct uart_pxa_port *)port;
322 unsigned long flags;
323
324 spin_lock_irqsave(&up->port.lock, flags);
325 if (break_state == -1)
326 up->lcr |= UART_LCR_SBC;
327 else
328 up->lcr &= ~UART_LCR_SBC;
329 serial_out(up, UART_LCR, up->lcr);
330 spin_unlock_irqrestore(&up->port.lock, flags);
331}
332
333static int serial_pxa_startup(struct uart_port *port)
334{
335 struct uart_pxa_port *up = (struct uart_pxa_port *)port;
336 unsigned long flags;
337 int retval;
338
339 if (port->line == 3) /* HWUART */
340 up->mcr |= UART_MCR_AFE;
341 else
342 up->mcr = 0;
343
344 up->port.uartclk = clk_get_rate(up->clk);
345
346 /*
347 * Allocate the IRQ
348 */
349 retval = request_irq(up->port.irq, serial_pxa_irq, 0, up->name, up);
350 if (retval)
351 return retval;
352
353 /*
354 * Clear the FIFO buffers and disable them.
355 * (they will be reenabled in set_termios())
356 */
357 serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO);
358 serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO |
359 UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT);
360 serial_out(up, UART_FCR, 0);
361
362 /*
363 * Clear the interrupt registers.
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 /*
371 * Now, initialize the UART
372 */
373 serial_out(up, UART_LCR, UART_LCR_WLEN8);
374
375 spin_lock_irqsave(&up->port.lock, flags);
376 up->port.mctrl |= TIOCM_OUT2;
377 serial_pxa_set_mctrl(&up->port, up->port.mctrl);
378 spin_unlock_irqrestore(&up->port.lock, flags);
379
380 /*
381 * Finally, enable interrupts. Note: Modem status interrupts
382 * are set via set_termios(), which will be occurring imminently
383 * anyway, so we don't enable them here.
384 */
385 up->ier = UART_IER_RLSI | UART_IER_RDI | UART_IER_RTOIE | UART_IER_UUE;
386 serial_out(up, UART_IER, up->ier);
387
388 /*
389 * And clear the interrupt registers again for luck.
390 */
391 (void) serial_in(up, UART_LSR);
392 (void) serial_in(up, UART_RX);
393 (void) serial_in(up, UART_IIR);
394 (void) serial_in(up, UART_MSR);
395
396 return 0;
397}
398
399static void serial_pxa_shutdown(struct uart_port *port)
400{
401 struct uart_pxa_port *up = (struct uart_pxa_port *)port;
402 unsigned long flags;
403
404 free_irq(up->port.irq, up);
405
406 /*
407 * Disable interrupts from this port
408 */
409 up->ier = 0;
410 serial_out(up, UART_IER, 0);
411
412 spin_lock_irqsave(&up->port.lock, flags);
413 up->port.mctrl &= ~TIOCM_OUT2;
414 serial_pxa_set_mctrl(&up->port, up->port.mctrl);
415 spin_unlock_irqrestore(&up->port.lock, flags);
416
417 /*
418 * Disable break condition and FIFOs
419 */
420 serial_out(up, UART_LCR, serial_in(up, UART_LCR) & ~UART_LCR_SBC);
421 serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO |
422 UART_FCR_CLEAR_RCVR |
423 UART_FCR_CLEAR_XMIT);
424 serial_out(up, UART_FCR, 0);
425}
426
427static void
428serial_pxa_set_termios(struct uart_port *port, struct ktermios *termios,
429 struct ktermios *old)
430{
431 struct uart_pxa_port *up = (struct uart_pxa_port *)port;
432 unsigned char cval, fcr = 0;
433 unsigned long flags;
434 unsigned int baud, quot;
435 unsigned int dll;
436
437 switch (termios->c_cflag & CSIZE) {
438 case CS5:
439 cval = UART_LCR_WLEN5;
440 break;
441 case CS6:
442 cval = UART_LCR_WLEN6;
443 break;
444 case CS7:
445 cval = UART_LCR_WLEN7;
446 break;
447 default:
448 case CS8:
449 cval = UART_LCR_WLEN8;
450 break;
451 }
452
453 if (termios->c_cflag & CSTOPB)
454 cval |= UART_LCR_STOP;
455 if (termios->c_cflag & PARENB)
456 cval |= UART_LCR_PARITY;
457 if (!(termios->c_cflag & PARODD))
458 cval |= UART_LCR_EPAR;
459
460 /*
461 * Ask the core to calculate the divisor for us.
462 */
463 baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk/16);
464 quot = uart_get_divisor(port, baud);
465
466 if ((up->port.uartclk / quot) < (2400 * 16))
467 fcr = UART_FCR_ENABLE_FIFO | UART_FCR_PXAR1;
468 else if ((up->port.uartclk / quot) < (230400 * 16))
469 fcr = UART_FCR_ENABLE_FIFO | UART_FCR_PXAR8;
470 else
471 fcr = UART_FCR_ENABLE_FIFO | UART_FCR_PXAR32;
472
473 /*
474 * Ok, we're now changing the port state. Do it with
475 * interrupts disabled.
476 */
477 spin_lock_irqsave(&up->port.lock, flags);
478
479 /*
480 * Ensure the port will be enabled.
481 * This is required especially for serial console.
482 */
483 up->ier |= UART_IER_UUE;
484
485 /*
486 * Update the per-port timeout.
487 */
488 uart_update_timeout(port, termios->c_cflag, baud);
489
490 up->port.read_status_mask = UART_LSR_OE | UART_LSR_THRE | UART_LSR_DR;
491 if (termios->c_iflag & INPCK)
492 up->port.read_status_mask |= UART_LSR_FE | UART_LSR_PE;
493 if (termios->c_iflag & (IGNBRK | BRKINT | PARMRK))
494 up->port.read_status_mask |= UART_LSR_BI;
495
496 /*
497 * Characters to ignore
498 */
499 up->port.ignore_status_mask = 0;
500 if (termios->c_iflag & IGNPAR)
501 up->port.ignore_status_mask |= UART_LSR_PE | UART_LSR_FE;
502 if (termios->c_iflag & IGNBRK) {
503 up->port.ignore_status_mask |= UART_LSR_BI;
504 /*
505 * If we're ignoring parity and break indicators,
506 * ignore overruns too (for real raw support).
507 */
508 if (termios->c_iflag & IGNPAR)
509 up->port.ignore_status_mask |= UART_LSR_OE;
510 }
511
512 /*
513 * ignore all characters if CREAD is not set
514 */
515 if ((termios->c_cflag & CREAD) == 0)
516 up->port.ignore_status_mask |= UART_LSR_DR;
517
518 /*
519 * CTS flow control flag and modem status interrupts
520 */
521 up->ier &= ~UART_IER_MSI;
522 if (UART_ENABLE_MS(&up->port, termios->c_cflag))
523 up->ier |= UART_IER_MSI;
524
525 serial_out(up, UART_IER, up->ier);
526
527 if (termios->c_cflag & CRTSCTS)
528 up->mcr |= UART_MCR_AFE;
529 else
530 up->mcr &= ~UART_MCR_AFE;
531
532 serial_out(up, UART_LCR, cval | UART_LCR_DLAB); /* set DLAB */
533 serial_out(up, UART_DLL, quot & 0xff); /* LS of divisor */
534
535 /*
536 * work around Errata #75 according to Intel(R) PXA27x Processor Family
537 * Specification Update (Nov 2005)
538 */
539 dll = serial_in(up, UART_DLL);
540 WARN_ON(dll != (quot & 0xff));
541
542 serial_out(up, UART_DLM, quot >> 8); /* MS of divisor */
543 serial_out(up, UART_LCR, cval); /* reset DLAB */
544 up->lcr = cval; /* Save LCR */
545 serial_pxa_set_mctrl(&up->port, up->port.mctrl);
546 serial_out(up, UART_FCR, fcr);
547 spin_unlock_irqrestore(&up->port.lock, flags);
548}
549
550static void
551serial_pxa_pm(struct uart_port *port, unsigned int state,
552 unsigned int oldstate)
553{
554 struct uart_pxa_port *up = (struct uart_pxa_port *)port;
555
556 if (!state)
557 clk_prepare_enable(up->clk);
558 else
559 clk_disable_unprepare(up->clk);
560}
561
562static void serial_pxa_release_port(struct uart_port *port)
563{
564}
565
566static int serial_pxa_request_port(struct uart_port *port)
567{
568 return 0;
569}
570
571static void serial_pxa_config_port(struct uart_port *port, int flags)
572{
573 struct uart_pxa_port *up = (struct uart_pxa_port *)port;
574 up->port.type = PORT_PXA;
575}
576
577static int
578serial_pxa_verify_port(struct uart_port *port, struct serial_struct *ser)
579{
580 /* we don't want the core code to modify any port params */
581 return -EINVAL;
582}
583
584static const char *
585serial_pxa_type(struct uart_port *port)
586{
587 struct uart_pxa_port *up = (struct uart_pxa_port *)port;
588 return up->name;
589}
590
591static struct uart_pxa_port *serial_pxa_ports[4];
592static struct uart_driver serial_pxa_reg;
593
594#ifdef CONFIG_SERIAL_PXA_CONSOLE
595
596#define BOTH_EMPTY (UART_LSR_TEMT | UART_LSR_THRE)
597
598/*
599 * Wait for transmitter & holding register to empty
600 */
601static void wait_for_xmitr(struct uart_pxa_port *up)
602{
603 unsigned int status, tmout = 10000;
604
605 /* Wait up to 10ms for the character(s) to be sent. */
606 do {
607 status = serial_in(up, UART_LSR);
608
609 if (status & UART_LSR_BI)
610 up->lsr_break_flag = UART_LSR_BI;
611
612 if (--tmout == 0)
613 break;
614 udelay(1);
615 } while ((status & BOTH_EMPTY) != BOTH_EMPTY);
616
617 /* Wait up to 1s for flow control if necessary */
618 if (up->port.flags & UPF_CONS_FLOW) {
619 tmout = 1000000;
620 while (--tmout &&
621 ((serial_in(up, UART_MSR) & UART_MSR_CTS) == 0))
622 udelay(1);
623 }
624}
625
626static void serial_pxa_console_putchar(struct uart_port *port, int ch)
627{
628 struct uart_pxa_port *up = (struct uart_pxa_port *)port;
629
630 wait_for_xmitr(up);
631 serial_out(up, UART_TX, ch);
632}
633
634/*
635 * Print a string to the serial port trying not to disturb
636 * any possible real use of the port...
637 *
638 * The console_lock must be held when we get here.
639 */
640static void
641serial_pxa_console_write(struct console *co, const char *s, unsigned int count)
642{
643 struct uart_pxa_port *up = serial_pxa_ports[co->index];
644 unsigned int ier;
645 unsigned long flags;
646 int locked = 1;
647
648 clk_enable(up->clk);
649 local_irq_save(flags);
650 if (up->port.sysrq)
651 locked = 0;
652 else if (oops_in_progress)
653 locked = spin_trylock(&up->port.lock);
654 else
655 spin_lock(&up->port.lock);
656
657 /*
658 * First save the IER then disable the interrupts
659 */
660 ier = serial_in(up, UART_IER);
661 serial_out(up, UART_IER, UART_IER_UUE);
662
663 uart_console_write(&up->port, s, count, serial_pxa_console_putchar);
664
665 /*
666 * Finally, wait for transmitter to become empty
667 * and restore the IER
668 */
669 wait_for_xmitr(up);
670 serial_out(up, UART_IER, ier);
671
672 if (locked)
673 spin_unlock(&up->port.lock);
674 local_irq_restore(flags);
675 clk_disable(up->clk);
676
677}
678
679#ifdef CONFIG_CONSOLE_POLL
680/*
681 * Console polling routines for writing and reading from the uart while
682 * in an interrupt or debug context.
683 */
684
685static int serial_pxa_get_poll_char(struct uart_port *port)
686{
687 struct uart_pxa_port *up = (struct uart_pxa_port *)port;
688 unsigned char lsr = serial_in(up, UART_LSR);
689
690 while (!(lsr & UART_LSR_DR))
691 lsr = serial_in(up, UART_LSR);
692
693 return serial_in(up, UART_RX);
694}
695
696
697static void serial_pxa_put_poll_char(struct uart_port *port,
698 unsigned char c)
699{
700 unsigned int ier;
701 struct uart_pxa_port *up = (struct uart_pxa_port *)port;
702
703 /*
704 * First save the IER then disable the interrupts
705 */
706 ier = serial_in(up, UART_IER);
707 serial_out(up, UART_IER, UART_IER_UUE);
708
709 wait_for_xmitr(up);
710 /*
711 * Send the character out.
712 */
713 serial_out(up, UART_TX, c);
714
715 /*
716 * Finally, wait for transmitter to become empty
717 * and restore the IER
718 */
719 wait_for_xmitr(up);
720 serial_out(up, UART_IER, ier);
721}
722
723#endif /* CONFIG_CONSOLE_POLL */
724
725static int __init
726serial_pxa_console_setup(struct console *co, char *options)
727{
728 struct uart_pxa_port *up;
729 int baud = 9600;
730 int bits = 8;
731 int parity = 'n';
732 int flow = 'n';
733
734 if (co->index == -1 || co->index >= serial_pxa_reg.nr)
735 co->index = 0;
736 up = serial_pxa_ports[co->index];
737 if (!up)
738 return -ENODEV;
739
740 if (options)
741 uart_parse_options(options, &baud, &parity, &bits, &flow);
742
743 return uart_set_options(&up->port, co, baud, parity, bits, flow);
744}
745
746static struct console serial_pxa_console = {
747 .name = "ttyS",
748 .write = serial_pxa_console_write,
749 .device = uart_console_device,
750 .setup = serial_pxa_console_setup,
751 .flags = CON_PRINTBUFFER,
752 .index = -1,
753 .data = &serial_pxa_reg,
754};
755
756#define PXA_CONSOLE &serial_pxa_console
757#else
758#define PXA_CONSOLE NULL
759#endif
760
761static const struct uart_ops serial_pxa_pops = {
762 .tx_empty = serial_pxa_tx_empty,
763 .set_mctrl = serial_pxa_set_mctrl,
764 .get_mctrl = serial_pxa_get_mctrl,
765 .stop_tx = serial_pxa_stop_tx,
766 .start_tx = serial_pxa_start_tx,
767 .stop_rx = serial_pxa_stop_rx,
768 .enable_ms = serial_pxa_enable_ms,
769 .break_ctl = serial_pxa_break_ctl,
770 .startup = serial_pxa_startup,
771 .shutdown = serial_pxa_shutdown,
772 .set_termios = serial_pxa_set_termios,
773 .pm = serial_pxa_pm,
774 .type = serial_pxa_type,
775 .release_port = serial_pxa_release_port,
776 .request_port = serial_pxa_request_port,
777 .config_port = serial_pxa_config_port,
778 .verify_port = serial_pxa_verify_port,
779#if defined(CONFIG_CONSOLE_POLL) && defined(CONFIG_SERIAL_PXA_CONSOLE)
780 .poll_get_char = serial_pxa_get_poll_char,
781 .poll_put_char = serial_pxa_put_poll_char,
782#endif
783};
784
785static struct uart_driver serial_pxa_reg = {
786 .owner = THIS_MODULE,
787 .driver_name = "PXA serial",
788 .dev_name = "ttyS",
789 .major = TTY_MAJOR,
790 .minor = 64,
791 .nr = 4,
792 .cons = PXA_CONSOLE,
793};
794
795#ifdef CONFIG_PM
796static int serial_pxa_suspend(struct device *dev)
797{
798 struct uart_pxa_port *sport = dev_get_drvdata(dev);
799
800 if (sport)
801 uart_suspend_port(&serial_pxa_reg, &sport->port);
802
803 return 0;
804}
805
806static int serial_pxa_resume(struct device *dev)
807{
808 struct uart_pxa_port *sport = dev_get_drvdata(dev);
809
810 if (sport)
811 uart_resume_port(&serial_pxa_reg, &sport->port);
812
813 return 0;
814}
815
816static const struct dev_pm_ops serial_pxa_pm_ops = {
817 .suspend = serial_pxa_suspend,
818 .resume = serial_pxa_resume,
819};
820#endif
821
822static const struct of_device_id serial_pxa_dt_ids[] = {
823 { .compatible = "mrvl,pxa-uart", },
824 { .compatible = "mrvl,mmp-uart", },
825 {}
826};
827
828static int serial_pxa_probe_dt(struct platform_device *pdev,
829 struct uart_pxa_port *sport)
830{
831 struct device_node *np = pdev->dev.of_node;
832 int ret;
833
834 if (!np)
835 return 1;
836
837 ret = of_alias_get_id(np, "serial");
838 if (ret < 0) {
839 dev_err(&pdev->dev, "failed to get alias id, errno %d\n", ret);
840 return ret;
841 }
842 sport->port.line = ret;
843 return 0;
844}
845
846static int serial_pxa_probe(struct platform_device *dev)
847{
848 struct uart_pxa_port *sport;
849 struct resource *mmres, *irqres;
850 int ret;
851
852 mmres = platform_get_resource(dev, IORESOURCE_MEM, 0);
853 irqres = platform_get_resource(dev, IORESOURCE_IRQ, 0);
854 if (!mmres || !irqres)
855 return -ENODEV;
856
857 sport = kzalloc(sizeof(struct uart_pxa_port), GFP_KERNEL);
858 if (!sport)
859 return -ENOMEM;
860
861 sport->clk = clk_get(&dev->dev, NULL);
862 if (IS_ERR(sport->clk)) {
863 ret = PTR_ERR(sport->clk);
864 goto err_free;
865 }
866
867 ret = clk_prepare(sport->clk);
868 if (ret) {
869 clk_put(sport->clk);
870 goto err_free;
871 }
872
873 sport->port.type = PORT_PXA;
874 sport->port.iotype = UPIO_MEM;
875 sport->port.mapbase = mmres->start;
876 sport->port.irq = irqres->start;
877 sport->port.fifosize = 64;
878 sport->port.ops = &serial_pxa_pops;
879 sport->port.dev = &dev->dev;
880 sport->port.flags = UPF_IOREMAP | UPF_BOOT_AUTOCONF;
881 sport->port.uartclk = clk_get_rate(sport->clk);
882
883 ret = serial_pxa_probe_dt(dev, sport);
884 if (ret > 0)
885 sport->port.line = dev->id;
886 else if (ret < 0)
887 goto err_clk;
888 if (sport->port.line >= ARRAY_SIZE(serial_pxa_ports)) {
889 dev_err(&dev->dev, "serial%d out of range\n", sport->port.line);
890 return -EINVAL;
891 }
892 snprintf(sport->name, PXA_NAME_LEN - 1, "UART%d", sport->port.line + 1);
893
894 sport->port.membase = ioremap(mmres->start, resource_size(mmres));
895 if (!sport->port.membase) {
896 ret = -ENOMEM;
897 goto err_clk;
898 }
899
900 serial_pxa_ports[sport->port.line] = sport;
901
902 uart_add_one_port(&serial_pxa_reg, &sport->port);
903 platform_set_drvdata(dev, sport);
904
905 return 0;
906
907 err_clk:
908 clk_unprepare(sport->clk);
909 clk_put(sport->clk);
910 err_free:
911 kfree(sport);
912 return ret;
913}
914
915static struct platform_driver serial_pxa_driver = {
916 .probe = serial_pxa_probe,
917
918 .driver = {
919 .name = "pxa2xx-uart",
920#ifdef CONFIG_PM
921 .pm = &serial_pxa_pm_ops,
922#endif
923 .suppress_bind_attrs = true,
924 .of_match_table = serial_pxa_dt_ids,
925 },
926};
927
928
929/* 8250 driver for PXA serial ports should be used */
930static int __init serial_pxa_init(void)
931{
932 int ret;
933
934 ret = uart_register_driver(&serial_pxa_reg);
935 if (ret != 0)
936 return ret;
937
938 ret = platform_driver_register(&serial_pxa_driver);
939 if (ret != 0)
940 uart_unregister_driver(&serial_pxa_reg);
941
942 return ret;
943}
944device_initcall(serial_pxa_init);