aboutsummaryrefslogtreecommitdiff
path: root/drivers/tty/serial/pxa.c
blob: 4302e6e3768e504d76f63d2be40198195c303290 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
/*
 *  Based on drivers/serial/8250.c by Russell King.
 *
 *  Author:	Nicolas Pitre
 *  Created:	Feb 20, 2003
 *  Copyright:	(C) 2003 Monta Vista Software, Inc.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * Note 1: This driver is made separate from the already too overloaded
 * 8250.c because it needs some kirks of its own and that'll make it
 * easier to add DMA support.
 *
 * Note 2: I'm too sick of device allocation policies for serial ports.
 * If someone else wants to request an "official" allocation of major/minor
 * for this driver please be my guest.  And don't forget that new hardware
 * to come from Intel might have more than 3 or 4 of those UARTs.  Let's
 * hope for a better port registration and dynamic device allocation scheme
 * with the serial core maintainer satisfaction to appear soon.
 */


#if defined(CONFIG_SERIAL_PXA_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
#define SUPPORT_SYSRQ
#endif

#include <linux/module.h>
#include <linux/ioport.h>
#include <linux/init.h>
#include <linux/console.h>
#include <linux/sysrq.h>
#include <linux/serial_reg.h>
#include <linux/circ_buf.h>
#include <linux/delay.h>
#include <linux/interrupt.h>
#include <linux/platform_device.h>
#include <linux/tty.h>
#include <linux/tty_flip.h>
#include <linux/serial_core.h>
#include <linux/clk.h>
#include <linux/io.h>
#include <linux/slab.h>

struct uart_pxa_port {
	struct uart_port        port;
	unsigned char           ier;
	unsigned char           lcr;
	unsigned char           mcr;
	unsigned int            lsr_break_flag;
	struct clk		*clk;
	char			*name;
};

static inline unsigned int serial_in(struct uart_pxa_port *up, int offset)
{
	offset <<= 2;
	return readl(up->port.membase + offset);
}

static inline void serial_out(struct uart_pxa_port *up, int offset, int value)
{
	offset <<= 2;
	writel(value, up->port.membase + offset);
}

static void serial_pxa_enable_ms(struct uart_port *port)
{
	struct uart_pxa_port *up = (struct uart_pxa_port *)port;

	up->ier |= UART_IER_MSI;
	serial_out(up, UART_IER, up->ier);
}

static void serial_pxa_stop_tx(struct uart_port *port)
{
	struct uart_pxa_port *up = (struct uart_pxa_port *)port;

	if (up->ier & UART_IER_THRI) {
		up->ier &= ~UART_IER_THRI;
		serial_out(up, UART_IER, up->ier);
	}
}

static void serial_pxa_stop_rx(struct uart_port *port)
{
	struct uart_pxa_port *up = (struct uart_pxa_port *)port;

	up->ier &= ~UART_IER_RLSI;
	up->port.read_status_mask &= ~UART_LSR_DR;
	serial_out(up, UART_IER, up->ier);
}

static inline void receive_chars(struct uart_pxa_port *up, int *status)
{
	struct tty_struct *tty = up->port.state->port.tty;
	unsigned int ch, flag;
	int max_count = 256;

	do {
		ch = serial_in(up, UART_RX);
		flag = TTY_NORMAL;
		up->port.icount.rx++;

		if (unlikely(*status & (UART_LSR_BI | UART_LSR_PE |
				       UART_LSR_FE | UART_LSR_OE))) {
			/*
			 * For statistics only
			 */
			if (*status & UART_LSR_BI) {
				*status &= ~(UART_LSR_FE | UART_LSR_PE);
				up->port.icount.brk++;
				/*
				 * We do the SysRQ and SAK checking
				 * here because otherwise the break
				 * may get masked by ignore_status_mask
				 * or read_status_mask.
				 */
				if (uart_handle_break(&up->port))
					goto ignore_char;
			} else if (*status & UART_LSR_PE)
				up->port.icount.parity++;
			else if (*status & UART_LSR_FE)
				up->port.icount.frame++;
			if (*status & UART_LSR_OE)
				up->port.icount.overrun++;

			/*
			 * Mask off conditions which should be ignored.
			 */
			*status &= up->port.read_status_mask;

#ifdef CONFIG_SERIAL_PXA_CONSOLE
			if (up->port.line == up->port.cons->index) {
				/* Recover the break flag from console xmit */
				*status |= up->lsr_break_flag;
				up->lsr_break_flag = 0;
			}
#endif
			if (*status & UART_LSR_BI) {
				flag = TTY_BREAK;
			} else if (*status & UART_LSR_PE)
				flag = TTY_PARITY;
			else if (*status & UART_LSR_FE)
				flag = TTY_FRAME;
		}

		if (uart_handle_sysrq_char(&up->port, ch))
			goto ignore_char;

		uart_insert_char(&up->port, *status, UART_LSR_OE, ch, flag);

	ignore_char:
		*status = serial_in(up, UART_LSR);
	} while ((*status & UART_LSR_DR) && (max_count-- > 0));
	tty_flip_buffer_push(tty);
}

static void transmit_chars(struct uart_pxa_port *up)
{
	struct circ_buf *xmit = &up->port.state->xmit;
	int count;

	if (up->port.x_char) {
		serial_out(up, UART_TX, up->port.x_char);
		up->port.icount.tx++;
		up->port.x_char = 0;
		return;
	}
	if (uart_circ_empty(xmit) || uart_tx_stopped(&up->port)) {
		serial_pxa_stop_tx(&up->port);
		return;
	}

	count = up->port.fifosize / 2;
	do {
		serial_out(up, UART_TX, xmit->buf[xmit->tail]);
		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
		up->port.icount.tx++;
		if (uart_circ_empty(xmit))
			break;
	} while (--count > 0);

	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
		uart_write_wakeup(&up->port);


	if (uart_circ_empty(xmit))
		serial_pxa_stop_tx(&up->port);
}

static void serial_pxa_start_tx(struct uart_port *port)
{
	struct uart_pxa_port *up = (struct uart_pxa_port *)port;

	if (!(up->ier & UART_IER_THRI)) {
		up->ier |= UART_IER_THRI;
		serial_out(up, UART_IER, up->ier);
	}
}

static inline void check_modem_status(struct uart_pxa_port *up)
{
	int status;

	status = serial_in(up, UART_MSR);

	if ((status & UART_MSR_ANY_DELTA) == 0)
		return;

	if (status & UART_MSR_TERI)
		up->port.icount.rng++;
	if (status & UART_MSR_DDSR)
		up->port.icount.dsr++;
	if (status & UART_MSR_DDCD)
		uart_handle_dcd_change(&up->port, status & UART_MSR_DCD);
	if (status & UART_MSR_DCTS)
		uart_handle_cts_change(&up->port, status & UART_MSR_CTS);

	wake_up_interruptible(&up->port.state->port.delta_msr_wait);
}

/*
 * This handles the interrupt from one port.
 */
static inline irqreturn_t serial_pxa_irq(int irq, void *dev_id)
{
	struct uart_pxa_port *up = dev_id;
	unsigned int iir, lsr;

	iir = serial_in(up, UART_IIR);
	if (iir & UART_IIR_NO_INT)
		return IRQ_NONE;
	lsr = serial_in(up, UART_LSR);
	if (lsr & UART_LSR_DR)
		receive_chars(up, &lsr);
	check_modem_status(up);
	if (lsr & UART_LSR_THRE)
		transmit_chars(up);
	return IRQ_HANDLED;
}

static unsigned int serial_pxa_tx_empty(struct uart_port *port)
{
	struct uart_pxa_port *up = (struct uart_pxa_port *)port;
	unsigned long flags;
	unsigned int ret;

	spin_lock_irqsave(&up->port.lock, flags);
	ret = serial_in(up, UART_LSR) & UART_LSR_TEMT ? TIOCSER_TEMT : 0;
	spin_unlock_irqrestore(&up->port.lock, flags);

	return ret;
}

static unsigned int serial_pxa_get_mctrl(struct uart_port *port)
{
	struct uart_pxa_port *up = (struct uart_pxa_port *)port;
	unsigned char status;
	unsigned int ret;

	status = serial_in(up, UART_MSR);

	ret = 0;
	if (status & UART_MSR_DCD)
		ret |= TIOCM_CAR;
	if (status & UART_MSR_RI)
		ret |= TIOCM_RNG;
	if (status & UART_MSR_DSR)
		ret |= TIOCM_DSR;
	if (status & UART_MSR_CTS)
		ret |= TIOCM_CTS;
	return ret;
}

static void serial_pxa_set_mctrl(struct uart_port *port, unsigned int mctrl)
{
	struct uart_pxa_port *up = (struct uart_pxa_port *)port;
	unsigned char mcr = 0;

	if (mctrl & TIOCM_RTS)
		mcr |= UART_MCR_RTS;
	if (mctrl & TIOCM_DTR)
		mcr |= UART_MCR_DTR;
	if (mctrl & TIOCM_OUT1)
		mcr |= UART_MCR_OUT1;
	if (mctrl & TIOCM_OUT2)
		mcr |= UART_MCR_OUT2;
	if (mctrl & TIOCM_LOOP)
		mcr |= UART_MCR_LOOP;

	mcr |= up->mcr;

	serial_out(up, UART_MCR, mcr);
}

static void serial_pxa_break_ctl(struct uart_port *port, int break_state)
{
	struct uart_pxa_port *up = (struct uart_pxa_port *)port;
	unsigned long flags;

	spin_lock_irqsave(&up->port.lock, flags);
	if (break_state == -1)
		up->lcr |= UART_LCR_SBC;
	else
		up->lcr &= ~UART_LCR_SBC;
	serial_out(up, UART_LCR, up->lcr);
	spin_unlock_irqrestore(&up->port.lock, flags);
}

#if 0
static void serial_pxa_dma_init(struct pxa_uart *up)
{
	up->rxdma =
		pxa_request_dma(up->name, DMA_PRIO_LOW, pxa_receive_dma, up);
	if (up->rxdma < 0)
		goto out;
	up->txdma =
		pxa_request_dma(up->name, DMA_PRIO_LOW, pxa_transmit_dma, up);
	if (up->txdma < 0)
		goto err_txdma;
	up->dmadesc = kmalloc(4 * sizeof(pxa_dma_desc), GFP_KERNEL);
	if (!up->dmadesc)
		goto err_alloc;

	/* ... */
err_alloc:
	pxa_free_dma(up->txdma);
err_rxdma:
	pxa_free_dma(up->rxdma);
out:
	return;
}
#endif

static int serial_pxa_startup(struct uart_port *port)
{
	struct uart_pxa_port *up = (struct uart_pxa_port *)port;
	unsigned long flags;
	int retval;

	if (port->line == 3) /* HWUART */
		up->mcr |= UART_MCR_AFE;
	else
		up->mcr = 0;

	up->port.uartclk = clk_get_rate(up->clk);

	/*
	 * Allocate the IRQ
	 */
	retval = request_irq(up->port.irq, serial_pxa_irq, 0, up->name, up);
	if (retval)
		return retval;

	/*
	 * Clear the FIFO buffers and disable them.
	 * (they will be reenabled in set_termios())
	 */
	serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO);
	serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO |
			UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT);
	serial_out(up, UART_FCR, 0);

	/*
	 * Clear the interrupt registers.
	 */
	(void) serial_in(up, UART_LSR);
	(void) serial_in(up, UART_RX);
	(void) serial_in(up, UART_IIR);
	(void) serial_in(up, UART_MSR);

	/*
	 * Now, initialize the UART
	 */
	serial_out(up, UART_LCR, UART_LCR_WLEN8);

	spin_lock_irqsave(&up->port.lock, flags);
	up->port.mctrl |= TIOCM_OUT2;
	serial_pxa_set_mctrl(&up->port, up->port.mctrl);
	spin_unlock_irqrestore(&up->port.lock, flags);

	/*
	 * Finally, enable interrupts.  Note: Modem status interrupts
	 * are set via set_termios(), which will be occurring imminently
	 * anyway, so we don't enable them here.
	 */
	up->ier = UART_IER_RLSI | UART_IER_RDI | UART_IER_RTOIE | UART_IER_UUE;
	serial_out(up, UART_IER, up->ier);

	/*
	 * And clear the interrupt registers again for luck.
	 */
	(void) serial_in(up, UART_LSR);
	(void) serial_in(up, UART_RX);
	(void) serial_in(up, UART_IIR);
	(void) serial_in(up, UART_MSR);

	return 0;
}

static void serial_pxa_shutdown(struct uart_port *port)
{
	struct uart_pxa_port *up = (struct uart_pxa_port *)port;
	unsigned long flags;

	free_irq(up->port.irq, up);

	/*
	 * Disable interrupts from this port
	 */
	up->ier = 0;
	serial_out(up, UART_IER, 0);

	spin_lock_irqsave(&up->port.lock, flags);
	up->port.mctrl &= ~TIOCM_OUT2;
	serial_pxa_set_mctrl(&up->port, up->port.mctrl);
	spin_unlock_irqrestore(&up->port.lock, flags);

	/*
	 * Disable break condition and FIFOs
	 */
	serial_out(up, UART_LCR, serial_in(up, UART_LCR) & ~UART_LCR_SBC);
	serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO |
				  UART_FCR_CLEAR_RCVR |
				  UART_FCR_CLEAR_XMIT);
	serial_out(up, UART_FCR, 0);
}

static void
serial_pxa_set_termios(struct uart_port *port, struct ktermios *termios,
		       struct ktermios *old)
{
	struct uart_pxa_port *up = (struct uart_pxa_port *)port;
	unsigned char cval, fcr = 0;
	unsigned long flags;
	unsigned int baud, quot;
	unsigned int dll;

	switch (termios->c_cflag & CSIZE) {
	case CS5:
		cval = UART_LCR_WLEN5;
		break;
	case CS6:
		cval = UART_LCR_WLEN6;
		break;
	case CS7:
		cval = UART_LCR_WLEN7;
		break;
	default:
	case CS8:
		cval = UART_LCR_WLEN8;
		break;
	}

	if (termios->c_cflag & CSTOPB)
		cval |= UART_LCR_STOP;
	if (termios->c_cflag & PARENB)
		cval |= UART_LCR_PARITY;
	if (!(termios->c_cflag & PARODD))
		cval |= UART_LCR_EPAR;

	/*
	 * Ask the core to calculate the divisor for us.
	 */
	baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk/16);
	quot = uart_get_divisor(port, baud);

	if ((up->port.uartclk / quot) < (2400 * 16))
		fcr = UART_FCR_ENABLE_FIFO | UART_FCR_PXAR1;
	else if ((up->port.uartclk / quot) < (230400 * 16))
		fcr = UART_FCR_ENABLE_FIFO | UART_FCR_PXAR8;
	else
		fcr = UART_FCR_ENABLE_FIFO | UART_FCR_PXAR32;

	/*
	 * Ok, we're now changing the port state.  Do it with
	 * interrupts disabled.
	 */
	spin_lock_irqsave(&up->port.lock, flags);

	/*
	 * Ensure the port will be enabled.
	 * This is required especially for serial console.
	 */
	up->ier |= UART_IER_UUE;

	/*
	 * Update the per-port timeout.
	 */
	uart_update_timeout(port, termios->c_cflag, baud);

	up->port.read_status_mask = UART_LSR_OE | UART_LSR_THRE | UART_LSR_DR;
	if (termios->c_iflag & INPCK)
		up->port.read_status_mask |= UART_LSR_FE | UART_LSR_PE;
	if (termios->c_iflag & (BRKINT | PARMRK))
		up->port.read_status_mask |= UART_LSR_BI;

	/*
	 * Characters to ignore
	 */
	up->port.ignore_status_mask = 0;
	if (termios->c_iflag & IGNPAR)
		up->port.ignore_status_mask |= UART_LSR_PE | UART_LSR_FE;
	if (termios->c_iflag & IGNBRK) {
		up->port.ignore_status_mask |= UART_LSR_BI;
		/*
		 * If we're ignoring parity and break indicators,
		 * ignore overruns too (for real raw support).
		 */
		if (termios->c_iflag & IGNPAR)
			up->port.ignore_status_mask |= UART_LSR_OE;
	}

	/*
	 * ignore all characters if CREAD is not set
	 */
	if ((termios->c_cflag & CREAD) == 0)
		up->port.ignore_status_mask |= UART_LSR_DR;

	/*
	 * CTS flow control flag and modem status interrupts
	 */
	up->ier &= ~UART_IER_MSI;
	if (UART_ENABLE_MS(&up->port, termios->c_cflag))
		up->ier |= UART_IER_MSI;

	serial_out(up, UART_IER, up->ier);

	if (termios->c_cflag & CRTSCTS)
		up->mcr |= UART_MCR_AFE;
	else
		up->mcr &= ~UART_MCR_AFE;

	serial_out(up, UART_LCR, cval | UART_LCR_DLAB);	/* set DLAB */
	serial_out(up, UART_DLL, quot & 0xff);		/* LS of divisor */

	/*
	 * work around Errata #75 according to Intel(R) PXA27x Processor Family
	 * Specification Update (Nov 2005)
	 */
	dll = serial_in(up, UART_DLL);
	WARN_ON(dll != (quot & 0xff));

	serial_out(up, UART_DLM, quot >> 8);		/* MS of divisor */
	serial_out(up, UART_LCR, cval);			/* reset DLAB */
	up->lcr = cval;					/* Save LCR */
	serial_pxa_set_mctrl(&up->port, up->port.mctrl);
	serial_out(up, UART_FCR, fcr);
	spin_unlock_irqrestore(&up->port.lock, flags);
}

static void
serial_pxa_pm(struct uart_port *port, unsigned int state,
	      unsigned int oldstate)
{
	struct uart_pxa_port *up = (struct uart_pxa_port *)port;

	if (!state)
		clk_enable(up->clk);
	else
		clk_disable(up->clk);
}

static void serial_pxa_release_port(struct uart_port *port)
{
}

static int serial_pxa_request_port(struct uart_port *port)
{
	return 0;
}

static void serial_pxa_config_port(struct uart_port *port, int flags)
{
	struct uart_pxa_port *up = (struct uart_pxa_port *)port;
	up->port.type = PORT_PXA;
}

static int
serial_pxa_verify_port(struct uart_port *port, struct serial_struct *ser)
{
	/* we don't want the core code to modify any port params */
	return -EINVAL;
}

static const char *
serial_pxa_type(struct uart_port *port)
{
	struct uart_pxa_port *up = (struct uart_pxa_port *)port;
	return up->name;
}

static struct uart_pxa_port *serial_pxa_ports[4];
static struct uart_driver serial_pxa_reg;

#ifdef CONFIG_SERIAL_PXA_CONSOLE

#define BOTH_EMPTY (UART_LSR_TEMT | UART_LSR_THRE)

/*
 *	Wait for transmitter & holding register to empty
 */
static inline void wait_for_xmitr(struct uart_pxa_port *up)
{
	unsigned int status, tmout = 10000;

	/* Wait up to 10ms for the character(s) to be sent. */
	do {
		status = serial_in(up, UART_LSR);

		if (status & UART_LSR_BI)
			up->lsr_break_flag = UART_LSR_BI;

		if (--tmout == 0)
			break;
		udelay(1);
	} while ((status & BOTH_EMPTY) != BOTH_EMPTY);

	/* Wait up to 1s for flow control if necessary */
	if (up->port.flags & UPF_CONS_FLOW) {
		tmout = 1000000;
		while (--tmout &&
		       ((serial_in(up, UART_MSR) & UART_MSR_CTS) == 0))
			udelay(1);
	}
}

static void serial_pxa_console_putchar(struct uart_port *port, int ch)
{
	struct uart_pxa_port *up = (struct uart_pxa_port *)port;

	wait_for_xmitr(up);
	serial_out(up, UART_TX, ch);
}

/*
 * Print a string to the serial port trying not to disturb
 * any possible real use of the port...
 *
 *	The console_lock must be held when we get here.
 */
static void
serial_pxa_console_write(struct console *co, const char *s, unsigned int count)
{
	struct uart_pxa_port *up = serial_pxa_ports[co->index];
	unsigned int ier;

	clk_enable(up->clk);

	/*
	 *	First save the IER then disable the interrupts
	 */
	ier = serial_in(up, UART_IER);
	serial_out(up, UART_IER, UART_IER_UUE);

	uart_console_write(&up->port, s, count, serial_pxa_console_putchar);

	/*
	 *	Finally, wait for transmitter to become empty
	 *	and restore the IER
	 */
	wait_for_xmitr(up);
	serial_out(up, UART_IER, ier);

	clk_disable(up->clk);
}

static int __init
serial_pxa_console_setup(struct console *co, char *options)
{
	struct uart_pxa_port *up;
	int baud = 9600;
	int bits = 8;
	int parity = 'n';
	int flow = 'n';

	if (co->index == -1 || co->index >= serial_pxa_reg.nr)
		co->index = 0;
	up = serial_pxa_ports[co->index];
	if (!up)
		return -ENODEV;

	if (options)
		uart_parse_options(options, &baud, &parity, &bits, &flow);

	return uart_set_options(&up->port, co, baud, parity, bits, flow);
}

static struct console serial_pxa_console = {
	.name		= "ttyS",
	.write		= serial_pxa_console_write,
	.device		= uart_console_device,
	.setup		= serial_pxa_console_setup,
	.flags		= CON_PRINTBUFFER,
	.index		= -1,
	.data		= &serial_pxa_reg,
};

#define PXA_CONSOLE	&serial_pxa_console
#else
#define PXA_CONSOLE	NULL
#endif

struct uart_ops serial_pxa_pops = {
	.tx_empty	= serial_pxa_tx_empty,
	.set_mctrl	= serial_pxa_set_mctrl,
	.get_mctrl	= serial_pxa_get_mctrl,
	.stop_tx	= serial_pxa_stop_tx,
	.start_tx	= serial_pxa_start_tx,
	.stop_rx	= serial_pxa_stop_rx,
	.enable_ms	= serial_pxa_enable_ms,
	.break_ctl	= serial_pxa_break_ctl,
	.startup	= serial_pxa_startup,
	.shutdown	= serial_pxa_shutdown,
	.set_termios	= serial_pxa_set_termios,
	.pm		= serial_pxa_pm,
	.type		= serial_pxa_type,
	.release_port	= serial_pxa_release_port,
	.request_port	= serial_pxa_request_port,
	.config_port	= serial_pxa_config_port,
	.verify_port	= serial_pxa_verify_port,
};

static struct uart_driver serial_pxa_reg = {
	.owner		= THIS_MODULE,
	.driver_name	= "PXA serial",
	.dev_name	= "ttyS",
	.major		= TTY_MAJOR,
	.minor		= 64,
	.nr		= 4,
	.cons		= PXA_CONSOLE,
};

#ifdef CONFIG_PM
static int serial_pxa_suspend(struct device *dev)
{
        struct uart_pxa_port *sport = dev_get_drvdata(dev);

        if (sport)
                uart_suspend_port(&serial_pxa_reg, &sport->port);

        return 0;
}

static int serial_pxa_resume(struct device *dev)
{
        struct uart_pxa_port *sport = dev_get_drvdata(dev);

        if (sport)
                uart_resume_port(&serial_pxa_reg, &sport->port);

        return 0;
}

static const struct dev_pm_ops serial_pxa_pm_ops = {
	.suspend	= serial_pxa_suspend,
	.resume		= serial_pxa_resume,
};
#endif

static int serial_pxa_probe(struct platform_device *dev)
{
	struct uart_pxa_port *sport;
	struct resource *mmres, *irqres;
	int ret;

	mmres = platform_get_resource(dev, IORESOURCE_MEM, 0);
	irqres = platform_get_resource(dev, IORESOURCE_IRQ, 0);
	if (!mmres || !irqres)
		return -ENODEV;

	sport = kzalloc(sizeof(struct uart_pxa_port), GFP_KERNEL);
	if (!sport)
		return -ENOMEM;

	sport->clk = clk_get(&dev->dev, NULL);
	if (IS_ERR(sport->clk)) {
		ret = PTR_ERR(sport->clk);
		goto err_free;
	}

	sport->port.type = PORT_PXA;
	sport->port.iotype = UPIO_MEM;
	sport->port.mapbase = mmres->start;
	sport->port.irq = irqres->start;
	sport->port.fifosize = 64;
	sport->port.ops = &serial_pxa_pops;
	sport->port.line = dev->id;
	sport->port.dev = &dev->dev;
	sport->port.flags = UPF_IOREMAP | UPF_BOOT_AUTOCONF;
	sport->port.uartclk = clk_get_rate(sport->clk);

	switch (dev->id) {
	case 0: sport->name = "FFUART"; break;
	case 1: sport->name = "BTUART"; break;
	case 2: sport->name = "STUART"; break;
	case 3: sport->name = "HWUART"; break;
	default:
		sport->name = "???";
		break;
	}

	sport->port.membase = ioremap(mmres->start, mmres->end - mmres->start + 1);
	if (!sport->port.membase) {
		ret = -ENOMEM;
		goto err_clk;
	}

	serial_pxa_ports[dev->id] = sport;

	uart_add_one_port(&serial_pxa_reg, &sport->port);
	platform_set_drvdata(dev, sport);

	return 0;

 err_clk:
	clk_put(sport->clk);
 err_free:
	kfree(sport);
	return ret;
}

static int serial_pxa_remove(struct platform_device *dev)
{
	struct uart_pxa_port *sport = platform_get_drvdata(dev);

	platform_set_drvdata(dev, NULL);

	uart_remove_one_port(&serial_pxa_reg, &sport->port);
	clk_put(sport->clk);
	kfree(sport);

	return 0;
}

static struct platform_driver serial_pxa_driver = {
        .probe          = serial_pxa_probe,
        .remove         = serial_pxa_remove,

	.driver		= {
	        .name	= "pxa2xx-uart",
		.owner	= THIS_MODULE,
#ifdef CONFIG_PM
		.pm	= &serial_pxa_pm_ops,
#endif
	},
};

int __init serial_pxa_init(void)
{
	int ret;

	ret = uart_register_driver(&serial_pxa_reg);
	if (ret != 0)
		return ret;

	ret = platform_driver_register(&serial_pxa_driver);
	if (ret != 0)
		uart_unregister_driver(&serial_pxa_reg);

	return ret;
}

void __exit serial_pxa_exit(void)
{
	platform_driver_unregister(&serial_pxa_driver);
	uart_unregister_driver(&serial_pxa_reg);
}

module_init(serial_pxa_init);
module_exit(serial_pxa_exit);

MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:pxa2xx-uart");