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