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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 unsigned int ch, flag;
102 int max_count = 256;
103
104 do {
105 /* work around Errata #20 according to
106 * Intel(R) PXA27x Processor Family
107 * Specification Update (May 2005)
108 *
109 * Step 2
110 * Disable the Reciever Time Out Interrupt via IER[RTOEI]
111 */
112 up->ier &= ~UART_IER_RTOIE;
113 serial_out(up, UART_IER, up->ier);
114
115 ch = serial_in(up, UART_RX);
116 flag = TTY_NORMAL;
117 up->port.icount.rx++;
118
119 if (unlikely(*status & (UART_LSR_BI | UART_LSR_PE |
120 UART_LSR_FE | UART_LSR_OE))) {
121 /*
122 * For statistics only
123 */
124 if (*status & UART_LSR_BI) {
125 *status &= ~(UART_LSR_FE | UART_LSR_PE);
126 up->port.icount.brk++;
127 /*
128 * We do the SysRQ and SAK checking
129 * here because otherwise the break
130 * may get masked by ignore_status_mask
131 * or read_status_mask.
132 */
133 if (uart_handle_break(&up->port))
134 goto ignore_char;
135 } else if (*status & UART_LSR_PE)
136 up->port.icount.parity++;
137 else if (*status & UART_LSR_FE)
138 up->port.icount.frame++;
139 if (*status & UART_LSR_OE)
140 up->port.icount.overrun++;
141
142 /*
143 * Mask off conditions which should be ignored.
144 */
145 *status &= up->port.read_status_mask;
146
147#ifdef CONFIG_SERIAL_PXA_CONSOLE
148 if (up->port.line == up->port.cons->index) {
149 /* Recover the break flag from console xmit */
150 *status |= up->lsr_break_flag;
151 up->lsr_break_flag = 0;
152 }
153#endif
154 if (*status & UART_LSR_BI) {
155 flag = TTY_BREAK;
156 } else if (*status & UART_LSR_PE)
157 flag = TTY_PARITY;
158 else if (*status & UART_LSR_FE)
159 flag = TTY_FRAME;
160 }
161
162 if (uart_handle_sysrq_char(&up->port, ch))
163 goto ignore_char;
164
165 uart_insert_char(&up->port, *status, UART_LSR_OE, ch, flag);
166
167 ignore_char:
168 *status = serial_in(up, UART_LSR);
169 } while ((*status & UART_LSR_DR) && (max_count-- > 0));
170 tty_flip_buffer_push(&up->port.state->port);
171
172 /* work around Errata #20 according to
173 * Intel(R) PXA27x Processor Family
174 * Specification Update (May 2005)
175 *
176 * Step 6:
177 * No more data in FIFO: Re-enable RTO interrupt via IER[RTOIE]
178 */
179 up->ier |= UART_IER_RTOIE;
180 serial_out(up, UART_IER, up->ier);
181}
182
183static void transmit_chars(struct uart_pxa_port *up)
184{
185 struct circ_buf *xmit = &up->port.state->xmit;
186 int count;
187
188 if (up->port.x_char) {
189 serial_out(up, UART_TX, up->port.x_char);
190 up->port.icount.tx++;
191 up->port.x_char = 0;
192 return;
193 }
194 if (uart_circ_empty(xmit) || uart_tx_stopped(&up->port)) {
195 serial_pxa_stop_tx(&up->port);
196 return;
197 }
198
199 count = up->port.fifosize / 2;
200 do {
201 serial_out(up, UART_TX, xmit->buf[xmit->tail]);
202 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
203 up->port.icount.tx++;
204 if (uart_circ_empty(xmit))
205 break;
206 } while (--count > 0);
207
208 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
209 uart_write_wakeup(&up->port);
210
211
212 if (uart_circ_empty(xmit))
213 serial_pxa_stop_tx(&up->port);
214}
215
216static void serial_pxa_start_tx(struct uart_port *port)
217{
218 struct uart_pxa_port *up = (struct uart_pxa_port *)port;
219
220 if (!(up->ier & UART_IER_THRI)) {
221 up->ier |= UART_IER_THRI;
222 serial_out(up, UART_IER, up->ier);
223 }
224}
225
226static inline void check_modem_status(struct uart_pxa_port *up)
227{
228 int status;
229
230 status = serial_in(up, UART_MSR);
231
232 if ((status & UART_MSR_ANY_DELTA) == 0)
233 return;
234
235 if (status & UART_MSR_TERI)
236 up->port.icount.rng++;
237 if (status & UART_MSR_DDSR)
238 up->port.icount.dsr++;
239 if (status & UART_MSR_DDCD)
240 uart_handle_dcd_change(&up->port, status & UART_MSR_DCD);
241 if (status & UART_MSR_DCTS)
242 uart_handle_cts_change(&up->port, status & UART_MSR_CTS);
243
244 wake_up_interruptible(&up->port.state->port.delta_msr_wait);
245}
246
247/*
248 * This handles the interrupt from one port.
249 */
250static inline irqreturn_t serial_pxa_irq(int irq, void *dev_id)
251{
252 struct uart_pxa_port *up = dev_id;
253 unsigned int iir, lsr;
254
255 iir = serial_in(up, UART_IIR);
256 if (iir & UART_IIR_NO_INT)
257 return IRQ_NONE;
258 lsr = serial_in(up, UART_LSR);
259 if (lsr & UART_LSR_DR)
260 receive_chars(up, &lsr);
261 check_modem_status(up);
262 if (lsr & UART_LSR_THRE)
263 transmit_chars(up);
264 return IRQ_HANDLED;
265}
266
267static unsigned int serial_pxa_tx_empty(struct uart_port *port)
268{
269 struct uart_pxa_port *up = (struct uart_pxa_port *)port;
270 unsigned long flags;
271 unsigned int ret;
272
273 spin_lock_irqsave(&up->port.lock, flags);
274 ret = serial_in(up, UART_LSR) & UART_LSR_TEMT ? TIOCSER_TEMT : 0;
275 spin_unlock_irqrestore(&up->port.lock, flags);
276
277 return ret;
278}
279
280static unsigned int serial_pxa_get_mctrl(struct uart_port *port)
281{
282 struct uart_pxa_port *up = (struct uart_pxa_port *)port;
283 unsigned char status;
284 unsigned int ret;
285
286 status = serial_in(up, UART_MSR);
287
288 ret = 0;
289 if (status & UART_MSR_DCD)
290 ret |= TIOCM_CAR;
291 if (status & UART_MSR_RI)
292 ret |= TIOCM_RNG;
293 if (status & UART_MSR_DSR)
294 ret |= TIOCM_DSR;
295 if (status & UART_MSR_CTS)
296 ret |= TIOCM_CTS;
297 return ret;
298}
299
300static void serial_pxa_set_mctrl(struct uart_port *port, unsigned int mctrl)
301{
302 struct uart_pxa_port *up = (struct uart_pxa_port *)port;
303 unsigned char mcr = 0;
304
305 if (mctrl & TIOCM_RTS)
306 mcr |= UART_MCR_RTS;
307 if (mctrl & TIOCM_DTR)
308 mcr |= UART_MCR_DTR;
309 if (mctrl & TIOCM_OUT1)
310 mcr |= UART_MCR_OUT1;
311 if (mctrl & TIOCM_OUT2)
312 mcr |= UART_MCR_OUT2;
313 if (mctrl & TIOCM_LOOP)
314 mcr |= UART_MCR_LOOP;
315
316 mcr |= up->mcr;
317
318 serial_out(up, UART_MCR, mcr);
319}
320
321static void serial_pxa_break_ctl(struct uart_port *port, int break_state)
322{
323 struct uart_pxa_port *up = (struct uart_pxa_port *)port;
324 unsigned long flags;
325
326 spin_lock_irqsave(&up->port.lock, flags);
327 if (break_state == -1)
328 up->lcr |= UART_LCR_SBC;
329 else
330 up->lcr &= ~UART_LCR_SBC;
331 serial_out(up, UART_LCR, up->lcr);
332 spin_unlock_irqrestore(&up->port.lock, flags);
333}
334
335static int serial_pxa_startup(struct uart_port *port)
336{
337 struct uart_pxa_port *up = (struct uart_pxa_port *)port;
338 unsigned long flags;
339 int retval;
340
341 if (port->line == 3) /* HWUART */
342 up->mcr |= UART_MCR_AFE;
343 else
344 up->mcr = 0;
345
346 up->port.uartclk = clk_get_rate(up->clk);
347
348 /*
349 * Allocate the IRQ
350 */
351 retval = request_irq(up->port.irq, serial_pxa_irq, 0, up->name, up);
352 if (retval)
353 return retval;
354
355 /*
356 * Clear the FIFO buffers and disable them.
357 * (they will be reenabled in set_termios())
358 */
359 serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO);
360 serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO |
361 UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT);
362 serial_out(up, UART_FCR, 0);
363
364 /*
365 * Clear the interrupt registers.
366 */
367 (void) serial_in(up, UART_LSR);
368 (void) serial_in(up, UART_RX);
369 (void) serial_in(up, UART_IIR);
370 (void) serial_in(up, UART_MSR);
371
372 /*
373 * Now, initialize the UART
374 */
375 serial_out(up, UART_LCR, UART_LCR_WLEN8);
376
377 spin_lock_irqsave(&up->port.lock, flags);
378 up->port.mctrl |= TIOCM_OUT2;
379 serial_pxa_set_mctrl(&up->port, up->port.mctrl);
380 spin_unlock_irqrestore(&up->port.lock, flags);
381
382 /*
383 * Finally, enable interrupts. Note: Modem status interrupts
384 * are set via set_termios(), which will be occurring imminently
385 * anyway, so we don't enable them here.
386 */
387 up->ier = UART_IER_RLSI | UART_IER_RDI | UART_IER_RTOIE | UART_IER_UUE;
388 serial_out(up, UART_IER, up->ier);
389
390 /*
391 * And clear the interrupt registers again for luck.
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 return 0;
399}
400
401static void serial_pxa_shutdown(struct uart_port *port)
402{
403 struct uart_pxa_port *up = (struct uart_pxa_port *)port;
404 unsigned long flags;
405
406 free_irq(up->port.irq, up);
407
408 /*
409 * Disable interrupts from this port
410 */
411 up->ier = 0;
412 serial_out(up, UART_IER, 0);
413
414 spin_lock_irqsave(&up->port.lock, flags);
415 up->port.mctrl &= ~TIOCM_OUT2;
416 serial_pxa_set_mctrl(&up->port, up->port.mctrl);
417 spin_unlock_irqrestore(&up->port.lock, flags);
418
419 /*
420 * Disable break condition and FIFOs
421 */
422 serial_out(up, UART_LCR, serial_in(up, UART_LCR) & ~UART_LCR_SBC);
423 serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO |
424 UART_FCR_CLEAR_RCVR |
425 UART_FCR_CLEAR_XMIT);
426 serial_out(up, UART_FCR, 0);
427}
428
429static void
430serial_pxa_set_termios(struct uart_port *port, struct ktermios *termios,
431 struct ktermios *old)
432{
433 struct uart_pxa_port *up = (struct uart_pxa_port *)port;
434 unsigned char cval, fcr = 0;
435 unsigned long flags;
436 unsigned int baud, quot;
437 unsigned int dll;
438
439 switch (termios->c_cflag & CSIZE) {
440 case CS5:
441 cval = UART_LCR_WLEN5;
442 break;
443 case CS6:
444 cval = UART_LCR_WLEN6;
445 break;
446 case CS7:
447 cval = UART_LCR_WLEN7;
448 break;
449 default:
450 case CS8:
451 cval = UART_LCR_WLEN8;
452 break;
453 }
454
455 if (termios->c_cflag & CSTOPB)
456 cval |= UART_LCR_STOP;
457 if (termios->c_cflag & PARENB)
458 cval |= UART_LCR_PARITY;
459 if (!(termios->c_cflag & PARODD))
460 cval |= UART_LCR_EPAR;
461
462 /*
463 * Ask the core to calculate the divisor for us.
464 */
465 baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk/16);
466 quot = uart_get_divisor(port, baud);
467
468 if ((up->port.uartclk / quot) < (2400 * 16))
469 fcr = UART_FCR_ENABLE_FIFO | UART_FCR_PXAR1;
470 else if ((up->port.uartclk / quot) < (230400 * 16))
471 fcr = UART_FCR_ENABLE_FIFO | UART_FCR_PXAR8;
472 else
473 fcr = UART_FCR_ENABLE_FIFO | UART_FCR_PXAR32;
474
475 /*
476 * Ok, we're now changing the port state. Do it with
477 * interrupts disabled.
478 */
479 spin_lock_irqsave(&up->port.lock, flags);
480
481 /*
482 * Ensure the port will be enabled.
483 * This is required especially for serial console.
484 */
485 up->ier |= UART_IER_UUE;
486
487 /*
488 * Update the per-port timeout.
489 */
490 uart_update_timeout(port, termios->c_cflag, baud);
491
492 up->port.read_status_mask = UART_LSR_OE | UART_LSR_THRE | UART_LSR_DR;
493 if (termios->c_iflag & INPCK)
494 up->port.read_status_mask |= UART_LSR_FE | UART_LSR_PE;
495 if (termios->c_iflag & (BRKINT | PARMRK))
496 up->port.read_status_mask |= UART_LSR_BI;
497
498 /*
499 * Characters to ignore
500 */
501 up->port.ignore_status_mask = 0;
502 if (termios->c_iflag & IGNPAR)
503 up->port.ignore_status_mask |= UART_LSR_PE | UART_LSR_FE;
504 if (termios->c_iflag & IGNBRK) {
505 up->port.ignore_status_mask |= UART_LSR_BI;
506 /*
507 * If we're ignoring parity and break indicators,
508 * ignore overruns too (for real raw support).
509 */
510 if (termios->c_iflag & IGNPAR)
511 up->port.ignore_status_mask |= UART_LSR_OE;
512 }
513
514 /*
515 * ignore all characters if CREAD is not set
516 */
517 if ((termios->c_cflag & CREAD) == 0)
518 up->port.ignore_status_mask |= UART_LSR_DR;
519
520 /*
521 * CTS flow control flag and modem status interrupts
522 */
523 up->ier &= ~UART_IER_MSI;
524 if (UART_ENABLE_MS(&up->port, termios->c_cflag))
525 up->ier |= UART_IER_MSI;
526
527 serial_out(up, UART_IER, up->ier);
528
529 if (termios->c_cflag & CRTSCTS)
530 up->mcr |= UART_MCR_AFE;
531 else
532 up->mcr &= ~UART_MCR_AFE;
533
534 serial_out(up, UART_LCR, cval | UART_LCR_DLAB); /* set DLAB */
535 serial_out(up, UART_DLL, quot & 0xff); /* LS of divisor */
536
537 /*
538 * work around Errata #75 according to Intel(R) PXA27x Processor Family
539 * Specification Update (Nov 2005)
540 */
541 dll = serial_in(up, UART_DLL);
542 WARN_ON(dll != (quot & 0xff));
543
544 serial_out(up, UART_DLM, quot >> 8); /* MS of divisor */
545 serial_out(up, UART_LCR, cval); /* reset DLAB */
546 up->lcr = cval; /* Save LCR */
547 serial_pxa_set_mctrl(&up->port, up->port.mctrl);
548 serial_out(up, UART_FCR, fcr);
549 spin_unlock_irqrestore(&up->port.lock, flags);
550}
551
552static void
553serial_pxa_pm(struct uart_port *port, unsigned int state,
554 unsigned int oldstate)
555{
556 struct uart_pxa_port *up = (struct uart_pxa_port *)port;
557
558 if (!state)
559 clk_prepare_enable(up->clk);
560 else
561 clk_disable_unprepare(up->clk);
562}
563
564static void serial_pxa_release_port(struct uart_port *port)
565{
566}
567
568static int serial_pxa_request_port(struct uart_port *port)
569{
570 return 0;
571}
572
573static void serial_pxa_config_port(struct uart_port *port, int flags)
574{
575 struct uart_pxa_port *up = (struct uart_pxa_port *)port;
576 up->port.type = PORT_PXA;
577}
578
579static int
580serial_pxa_verify_port(struct uart_port *port, struct serial_struct *ser)
581{
582 /* we don't want the core code to modify any port params */
583 return -EINVAL;
584}
585
586static const char *
587serial_pxa_type(struct uart_port *port)
588{
589 struct uart_pxa_port *up = (struct uart_pxa_port *)port;
590 return up->name;
591}
592
593static struct uart_pxa_port *serial_pxa_ports[4];
594static struct uart_driver serial_pxa_reg;
595
596#ifdef CONFIG_SERIAL_PXA_CONSOLE
597
598#define BOTH_EMPTY (UART_LSR_TEMT | UART_LSR_THRE)
599
600/*
601 * Wait for transmitter & holding register to empty
602 */
603static inline void wait_for_xmitr(struct uart_pxa_port *up)
604{
605 unsigned int status, tmout = 10000;
606
607 /* Wait up to 10ms for the character(s) to be sent. */
608 do {
609 status = serial_in(up, UART_LSR);
610
611 if (status & UART_LSR_BI)
612 up->lsr_break_flag = UART_LSR_BI;
613
614 if (--tmout == 0)
615 break;
616 udelay(1);
617 } while ((status & BOTH_EMPTY) != BOTH_EMPTY);
618
619 /* Wait up to 1s for flow control if necessary */
620 if (up->port.flags & UPF_CONS_FLOW) {
621 tmout = 1000000;
622 while (--tmout &&
623 ((serial_in(up, UART_MSR) & UART_MSR_CTS) == 0))
624 udelay(1);
625 }
626}
627
628static void serial_pxa_console_putchar(struct uart_port *port, int ch)
629{
630 struct uart_pxa_port *up = (struct uart_pxa_port *)port;
631
632 wait_for_xmitr(up);
633 serial_out(up, UART_TX, ch);
634}
635
636/*
637 * Print a string to the serial port trying not to disturb
638 * any possible real use of the port...
639 *
640 * The console_lock must be held when we get here.
641 */
642static void
643serial_pxa_console_write(struct console *co, const char *s, unsigned int count)
644{
645 struct uart_pxa_port *up = serial_pxa_ports[co->index];
646 unsigned int ier;
647 unsigned long flags;
648 int locked = 1;
649
650 clk_enable(up->clk);
651 local_irq_save(flags);
652 if (up->port.sysrq)
653 locked = 0;
654 else if (oops_in_progress)
655 locked = spin_trylock(&up->port.lock);
656 else
657 spin_lock(&up->port.lock);
658
659 /*
660 * First save the IER then disable the interrupts
661 */
662 ier = serial_in(up, UART_IER);
663 serial_out(up, UART_IER, UART_IER_UUE);
664
665 uart_console_write(&up->port, s, count, serial_pxa_console_putchar);
666
667 /*
668 * Finally, wait for transmitter to become empty
669 * and restore the IER
670 */
671 wait_for_xmitr(up);
672 serial_out(up, UART_IER, ier);
673
674 if (locked)
675 spin_unlock(&up->port.lock);
676 local_irq_restore(flags);
677 clk_disable(up->clk);
678
679}
680
681#ifdef CONFIG_CONSOLE_POLL
682/*
683 * Console polling routines for writing and reading from the uart while
684 * in an interrupt or debug context.
685 */
686
687static int serial_pxa_get_poll_char(struct uart_port *port)
688{
689 struct uart_pxa_port *up = (struct uart_pxa_port *)port;
690 unsigned char lsr = serial_in(up, UART_LSR);
691
692 while (!(lsr & UART_LSR_DR))
693 lsr = serial_in(up, UART_LSR);
694
695 return serial_in(up, UART_RX);
696}
697
698
699static void serial_pxa_put_poll_char(struct uart_port *port,
700 unsigned char c)
701{
702 unsigned int ier;
703 struct uart_pxa_port *up = (struct uart_pxa_port *)port;
704
705 /*
706 * First save the IER then disable the interrupts
707 */
708 ier = serial_in(up, UART_IER);
709 serial_out(up, UART_IER, UART_IER_UUE);
710
711 wait_for_xmitr(up);
712 /*
713 * Send the character out.
714 * If a LF, also do CR...
715 */
716 serial_out(up, UART_TX, c);
717 if (c == 10) {
718 wait_for_xmitr(up);
719 serial_out(up, UART_TX, 13);
720 }
721
722 /*
723 * Finally, wait for transmitter to become empty
724 * and restore the IER
725 */
726 wait_for_xmitr(up);
727 serial_out(up, UART_IER, ier);
728}
729
730#endif /* CONFIG_CONSOLE_POLL */
731
732static int __init
733serial_pxa_console_setup(struct console *co, char *options)
734{
735 struct uart_pxa_port *up;
736 int baud = 9600;
737 int bits = 8;
738 int parity = 'n';
739 int flow = 'n';
740
741 if (co->index == -1 || co->index >= serial_pxa_reg.nr)
742 co->index = 0;
743 up = serial_pxa_ports[co->index];
744 if (!up)
745 return -ENODEV;
746
747 if (options)
748 uart_parse_options(options, &baud, &parity, &bits, &flow);
749
750 return uart_set_options(&up->port, co, baud, parity, bits, flow);
751}
752
753static struct console serial_pxa_console = {
754 .name = "ttyS",
755 .write = serial_pxa_console_write,
756 .device = uart_console_device,
757 .setup = serial_pxa_console_setup,
758 .flags = CON_PRINTBUFFER,
759 .index = -1,
760 .data = &serial_pxa_reg,
761};
762
763#define PXA_CONSOLE &serial_pxa_console
764#else
765#define PXA_CONSOLE NULL
766#endif
767
768static struct uart_ops serial_pxa_pops = {
769 .tx_empty = serial_pxa_tx_empty,
770 .set_mctrl = serial_pxa_set_mctrl,
771 .get_mctrl = serial_pxa_get_mctrl,
772 .stop_tx = serial_pxa_stop_tx,
773 .start_tx = serial_pxa_start_tx,
774 .stop_rx = serial_pxa_stop_rx,
775 .enable_ms = serial_pxa_enable_ms,
776 .break_ctl = serial_pxa_break_ctl,
777 .startup = serial_pxa_startup,
778 .shutdown = serial_pxa_shutdown,
779 .set_termios = serial_pxa_set_termios,
780 .pm = serial_pxa_pm,
781 .type = serial_pxa_type,
782 .release_port = serial_pxa_release_port,
783 .request_port = serial_pxa_request_port,
784 .config_port = serial_pxa_config_port,
785 .verify_port = serial_pxa_verify_port,
786#ifdef CONFIG_CONSOLE_POLL
787 .poll_get_char = serial_pxa_get_poll_char,
788 .poll_put_char = serial_pxa_put_poll_char,
789#endif
790};
791
792static struct uart_driver serial_pxa_reg = {
793 .owner = THIS_MODULE,
794 .driver_name = "PXA serial",
795 .dev_name = "ttyS",
796 .major = TTY_MAJOR,
797 .minor = 64,
798 .nr = 4,
799 .cons = PXA_CONSOLE,
800};
801
802#ifdef CONFIG_PM
803static int serial_pxa_suspend(struct device *dev)
804{
805 struct uart_pxa_port *sport = dev_get_drvdata(dev);
806
807 if (sport)
808 uart_suspend_port(&serial_pxa_reg, &sport->port);
809
810 return 0;
811}
812
813static int serial_pxa_resume(struct device *dev)
814{
815 struct uart_pxa_port *sport = dev_get_drvdata(dev);
816
817 if (sport)
818 uart_resume_port(&serial_pxa_reg, &sport->port);
819
820 return 0;
821}
822
823static const struct dev_pm_ops serial_pxa_pm_ops = {
824 .suspend = serial_pxa_suspend,
825 .resume = serial_pxa_resume,
826};
827#endif
828
829static struct of_device_id serial_pxa_dt_ids[] = {
830 { .compatible = "mrvl,pxa-uart", },
831 { .compatible = "mrvl,mmp-uart", },
832 {}
833};
834MODULE_DEVICE_TABLE(of, serial_pxa_dt_ids);
835
836static int serial_pxa_probe_dt(struct platform_device *pdev,
837 struct uart_pxa_port *sport)
838{
839 struct device_node *np = pdev->dev.of_node;
840 int ret;
841
842 if (!np)
843 return 1;
844
845 ret = of_alias_get_id(np, "serial");
846 if (ret < 0) {
847 dev_err(&pdev->dev, "failed to get alias id, errno %d\n", ret);
848 return ret;
849 }
850 sport->port.line = ret;
851 return 0;
852}
853
854static int serial_pxa_probe(struct platform_device *dev)
855{
856 struct uart_pxa_port *sport;
857 struct resource *mmres, *irqres;
858 int ret;
859
860 mmres = platform_get_resource(dev, IORESOURCE_MEM, 0);
861 irqres = platform_get_resource(dev, IORESOURCE_IRQ, 0);
862 if (!mmres || !irqres)
863 return -ENODEV;
864
865 sport = kzalloc(sizeof(struct uart_pxa_port), GFP_KERNEL);
866 if (!sport)
867 return -ENOMEM;
868
869 sport->clk = clk_get(&dev->dev, NULL);
870 if (IS_ERR(sport->clk)) {
871 ret = PTR_ERR(sport->clk);
872 goto err_free;
873 }
874
875 ret = clk_prepare(sport->clk);
876 if (ret) {
877 clk_put(sport->clk);
878 goto err_free;
879 }
880
881 sport->port.type = PORT_PXA;
882 sport->port.iotype = UPIO_MEM;
883 sport->port.mapbase = mmres->start;
884 sport->port.irq = irqres->start;
885 sport->port.fifosize = 64;
886 sport->port.ops = &serial_pxa_pops;
887 sport->port.dev = &dev->dev;
888 sport->port.flags = UPF_IOREMAP | UPF_BOOT_AUTOCONF;
889 sport->port.uartclk = clk_get_rate(sport->clk);
890
891 ret = serial_pxa_probe_dt(dev, sport);
892 if (ret > 0)
893 sport->port.line = dev->id;
894 else if (ret < 0)
895 goto err_clk;
896 snprintf(sport->name, PXA_NAME_LEN - 1, "UART%d", sport->port.line + 1);
897
898 sport->port.membase = ioremap(mmres->start, resource_size(mmres));
899 if (!sport->port.membase) {
900 ret = -ENOMEM;
901 goto err_clk;
902 }
903
904 serial_pxa_ports[sport->port.line] = sport;
905
906 uart_add_one_port(&serial_pxa_reg, &sport->port);
907 platform_set_drvdata(dev, sport);
908
909 return 0;
910
911 err_clk:
912 clk_unprepare(sport->clk);
913 clk_put(sport->clk);
914 err_free:
915 kfree(sport);
916 return ret;
917}
918
919static int serial_pxa_remove(struct platform_device *dev)
920{
921 struct uart_pxa_port *sport = platform_get_drvdata(dev);
922
923 uart_remove_one_port(&serial_pxa_reg, &sport->port);
924
925 clk_unprepare(sport->clk);
926 clk_put(sport->clk);
927 kfree(sport);
928
929 return 0;
930}
931
932static struct platform_driver serial_pxa_driver = {
933 .probe = serial_pxa_probe,
934 .remove = serial_pxa_remove,
935
936 .driver = {
937 .name = "pxa2xx-uart",
938 .owner = THIS_MODULE,
939#ifdef CONFIG_PM
940 .pm = &serial_pxa_pm_ops,
941#endif
942 .of_match_table = serial_pxa_dt_ids,
943 },
944};
945
946static int __init serial_pxa_init(void)
947{
948 int ret;
949
950 ret = uart_register_driver(&serial_pxa_reg);
951 if (ret != 0)
952 return ret;
953
954 ret = platform_driver_register(&serial_pxa_driver);
955 if (ret != 0)
956 uart_unregister_driver(&serial_pxa_reg);
957
958 return ret;
959}
960
961static void __exit serial_pxa_exit(void)
962{
963 platform_driver_unregister(&serial_pxa_driver);
964 uart_unregister_driver(&serial_pxa_reg);
965}
966
967module_init(serial_pxa_init);
968module_exit(serial_pxa_exit);
969
970MODULE_LICENSE("GPL");
971MODULE_ALIAS("platform:pxa2xx-uart");