summaryrefslogtreecommitdiffstats
path: root/arch/arm/plat-omap/dmtimer.c
blob: 10ec31b8a3a2844f3221d0651057e6c9380029d0 (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
878
879
880
881
882
883
884
885
886
887
/*
 * linux/arch/arm/plat-omap/dmtimer.c
 *
 * OMAP Dual-Mode Timers
 *
 * Copyright (C) 2010 Texas Instruments Incorporated - http://www.ti.com/
 * Tarun Kanti DebBarma <tarun.kanti@ti.com>
 * Thara Gopinath <thara@ti.com>
 *
 * dmtimer adaptation to platform_driver.
 *
 * Copyright (C) 2005 Nokia Corporation
 * OMAP2 support by Juha Yrjola
 * API improvements and OMAP2 clock framework support by Timo Teras
 *
 * Copyright (C) 2009 Texas Instruments
 * Added OMAP4 support - Santosh Shilimkar <santosh.shilimkar@ti.com>
 *
 * 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.
 *
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN
 * NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * You should have received a copy of the  GNU General Public License along
 * with this program; if not, write  to the Free Software Foundation, Inc.,
 * 675 Mass Ave, Cambridge, MA 02139, USA.
 */

#include <linux/module.h>
#include <linux/io.h>
#include <linux/device.h>
#include <linux/err.h>
#include <linux/pm_runtime.h>
#include <linux/of.h>
#include <linux/of_device.h>

#include <plat/dmtimer.h>

static u32 omap_reserved_systimers;
static LIST_HEAD(omap_timer_list);
static DEFINE_SPINLOCK(dm_timer_lock);

/**
 * omap_dm_timer_read_reg - read timer registers in posted and non-posted mode
 * @timer:      timer pointer over which read operation to perform
 * @reg:        lowest byte holds the register offset
 *
 * The posted mode bit is encoded in reg. Note that in posted mode write
 * pending bit must be checked. Otherwise a read of a non completed write
 * will produce an error.
 */
static inline u32 omap_dm_timer_read_reg(struct omap_dm_timer *timer, u32 reg)
{
	WARN_ON((reg & 0xff) < _OMAP_TIMER_WAKEUP_EN_OFFSET);
	return __omap_dm_timer_read(timer, reg, timer->posted);
}

/**
 * omap_dm_timer_write_reg - write timer registers in posted and non-posted mode
 * @timer:      timer pointer over which write operation is to perform
 * @reg:        lowest byte holds the register offset
 * @value:      data to write into the register
 *
 * The posted mode bit is encoded in reg. Note that in posted mode the write
 * pending bit must be checked. Otherwise a write on a register which has a
 * pending write will be lost.
 */
static void omap_dm_timer_write_reg(struct omap_dm_timer *timer, u32 reg,
						u32 value)
{
	WARN_ON((reg & 0xff) < _OMAP_TIMER_WAKEUP_EN_OFFSET);
	__omap_dm_timer_write(timer, reg, value, timer->posted);
}

static void omap_timer_restore_context(struct omap_dm_timer *timer)
{
	if (timer->revision == 1)
		__raw_writel(timer->context.tistat, timer->sys_stat);

	__raw_writel(timer->context.tisr, timer->irq_stat);
	omap_dm_timer_write_reg(timer, OMAP_TIMER_WAKEUP_EN_REG,
				timer->context.twer);
	omap_dm_timer_write_reg(timer, OMAP_TIMER_COUNTER_REG,
				timer->context.tcrr);
	omap_dm_timer_write_reg(timer, OMAP_TIMER_LOAD_REG,
				timer->context.tldr);
	omap_dm_timer_write_reg(timer, OMAP_TIMER_MATCH_REG,
				timer->context.tmar);
	omap_dm_timer_write_reg(timer, OMAP_TIMER_IF_CTRL_REG,
				timer->context.tsicr);
	__raw_writel(timer->context.tier, timer->irq_ena);
	omap_dm_timer_write_reg(timer, OMAP_TIMER_CTRL_REG,
				timer->context.tclr);
}

static void omap_dm_timer_wait_for_reset(struct omap_dm_timer *timer)
{
	int c;

	if (!timer->sys_stat)
		return;

	c = 0;
	while (!(__raw_readl(timer->sys_stat) & 1)) {
		c++;
		if (c > 100000) {
			printk(KERN_ERR "Timer failed to reset\n");
			return;
		}
	}
}

static void omap_dm_timer_reset(struct omap_dm_timer *timer)
{
	if (timer->pdev->id != 1) {
		omap_dm_timer_write_reg(timer, OMAP_TIMER_IF_CTRL_REG, 0x06);
		omap_dm_timer_wait_for_reset(timer);
	}

	__omap_dm_timer_reset(timer, 0, 0);
}

int omap_dm_timer_prepare(struct omap_dm_timer *timer)
{
	/*
	 * FIXME: OMAP1 devices do not use the clock framework for dmtimers so
	 * do not call clk_get() for these devices.
	 */
	if (!(timer->capability & OMAP_TIMER_NEEDS_RESET)) {
		timer->fclk = clk_get(&timer->pdev->dev, "fck");
		if (WARN_ON_ONCE(IS_ERR_OR_NULL(timer->fclk))) {
			timer->fclk = NULL;
			dev_err(&timer->pdev->dev, ": No fclk handle.\n");
			return -EINVAL;
		}
	}

	omap_dm_timer_enable(timer);

	if (timer->capability & OMAP_TIMER_NEEDS_RESET)
		omap_dm_timer_reset(timer);

	__omap_dm_timer_enable_posted(timer);
	omap_dm_timer_disable(timer);

	return omap_dm_timer_set_source(timer, OMAP_TIMER_SRC_32_KHZ);
}

static inline u32 omap_dm_timer_reserved_systimer(int id)
{
	return (omap_reserved_systimers & (1 << (id - 1))) ? 1 : 0;
}

int omap_dm_timer_reserve_systimer(int id)
{
	if (omap_dm_timer_reserved_systimer(id))
		return -ENODEV;

	omap_reserved_systimers |= (1 << (id - 1));

	return 0;
}

struct omap_dm_timer *omap_dm_timer_request(void)
{
	struct omap_dm_timer *timer = NULL, *t;
	unsigned long flags;
	int ret = 0;

	spin_lock_irqsave(&dm_timer_lock, flags);
	list_for_each_entry(t, &omap_timer_list, node) {
		if (t->reserved)
			continue;

		timer = t;
		timer->reserved = 1;
		break;
	}
	spin_unlock_irqrestore(&dm_timer_lock, flags);

	if (timer) {
		ret = omap_dm_timer_prepare(timer);
		if (ret) {
			timer->reserved = 0;
			timer = NULL;
		}
	}

	if (!timer)
		pr_debug("%s: timer request failed!\n", __func__);

	return timer;
}
EXPORT_SYMBOL_GPL(omap_dm_timer_request);

struct omap_dm_timer *omap_dm_timer_request_specific(int id)
{
	struct omap_dm_timer *timer = NULL, *t;
	unsigned long flags;
	int ret = 0;

	/* Requesting timer by ID is not supported when device tree is used */
	if (of_have_populated_dt()) {
		pr_warn("%s: Please use omap_dm_timer_request_by_cap()\n",
			__func__);
		return NULL;
	}

	spin_lock_irqsave(&dm_timer_lock, flags);
	list_for_each_entry(t, &omap_timer_list, node) {
		if (t->pdev->id == id && !t->reserved) {
			timer = t;
			timer->reserved = 1;
			break;
		}
	}
	spin_unlock_irqrestore(&dm_timer_lock, flags);

	if (timer) {
		ret = omap_dm_timer_prepare(timer);
		if (ret) {
			timer->reserved = 0;
			timer = NULL;
		}
	}

	if (!timer)
		pr_debug("%s: timer%d request failed!\n", __func__, id);

	return timer;
}
EXPORT_SYMBOL_GPL(omap_dm_timer_request_specific);

/**
 * omap_dm_timer_request_by_cap - Request a timer by capability
 * @cap:	Bit mask of capabilities to match
 *
 * Find a timer based upon capabilities bit mask. Callers of this function
 * should use the definitions found in the plat/dmtimer.h file under the
 * comment "timer capabilities used in hwmod database". Returns pointer to
 * timer handle on success and a NULL pointer on failure.
 */
struct omap_dm_timer *omap_dm_timer_request_by_cap(u32 cap)
{
	struct omap_dm_timer *timer = NULL, *t;
	unsigned long flags;

	if (!cap)
		return NULL;

	spin_lock_irqsave(&dm_timer_lock, flags);
	list_for_each_entry(t, &omap_timer_list, node) {
		if ((!t->reserved) && ((t->capability & cap) == cap)) {
			/*
			 * If timer is not NULL, we have already found one timer
			 * but it was not an exact match because it had more
			 * capabilites that what was required. Therefore,
			 * unreserve the last timer found and see if this one
			 * is a better match.
			 */
			if (timer)
				timer->reserved = 0;

			timer = t;
			timer->reserved = 1;

			/* Exit loop early if we find an exact match */
			if (t->capability == cap)
				break;
		}
	}
	spin_unlock_irqrestore(&dm_timer_lock, flags);

	if (timer && omap_dm_timer_prepare(timer)) {
		timer->reserved = 0;
		timer = NULL;
	}

	if (!timer)
		pr_debug("%s: timer request failed!\n", __func__);

	return timer;
}
EXPORT_SYMBOL_GPL(omap_dm_timer_request_by_cap);

int omap_dm_timer_free(struct omap_dm_timer *timer)
{
	if (unlikely(!timer))
		return -EINVAL;

	clk_put(timer->fclk);

	WARN_ON(!timer->reserved);
	timer->reserved = 0;
	return 0;
}
EXPORT_SYMBOL_GPL(omap_dm_timer_free);

void omap_dm_timer_enable(struct omap_dm_timer *timer)
{
	pm_runtime_get_sync(&timer->pdev->dev);
}
EXPORT_SYMBOL_GPL(omap_dm_timer_enable);

void omap_dm_timer_disable(struct omap_dm_timer *timer)
{
	pm_runtime_put_sync(&timer->pdev->dev);
}
EXPORT_SYMBOL_GPL(omap_dm_timer_disable);

int omap_dm_timer_get_irq(struct omap_dm_timer *timer)
{
	if (timer)
		return timer->irq;
	return -EINVAL;
}
EXPORT_SYMBOL_GPL(omap_dm_timer_get_irq);

#if defined(CONFIG_ARCH_OMAP1)
#include <mach/hardware.h>
/**
 * omap_dm_timer_modify_idlect_mask - Check if any running timers use ARMXOR
 * @inputmask: current value of idlect mask
 */
__u32 omap_dm_timer_modify_idlect_mask(__u32 inputmask)
{
	int i = 0;
	struct omap_dm_timer *timer = NULL;
	unsigned long flags;

	/* If ARMXOR cannot be idled this function call is unnecessary */
	if (!(inputmask & (1 << 1)))
		return inputmask;

	/* If any active timer is using ARMXOR return modified mask */
	spin_lock_irqsave(&dm_timer_lock, flags);
	list_for_each_entry(timer, &omap_timer_list, node) {
		u32 l;

		l = omap_dm_timer_read_reg(timer, OMAP_TIMER_CTRL_REG);
		if (l & OMAP_TIMER_CTRL_ST) {
			if (((omap_readl(MOD_CONF_CTRL_1) >> (i * 2)) & 0x03) == 0)
				inputmask &= ~(1 << 1);
			else
				inputmask &= ~(1 << 2);
		}
		i++;
	}
	spin_unlock_irqrestore(&dm_timer_lock, flags);

	return inputmask;
}
EXPORT_SYMBOL_GPL(omap_dm_timer_modify_idlect_mask);

#else

struct clk *omap_dm_timer_get_fclk(struct omap_dm_timer *timer)
{
	if (timer)
		return timer->fclk;
	return NULL;
}
EXPORT_SYMBOL_GPL(omap_dm_timer_get_fclk);

__u32 omap_dm_timer_modify_idlect_mask(__u32 inputmask)
{
	BUG();

	return 0;
}
EXPORT_SYMBOL_GPL(omap_dm_timer_modify_idlect_mask);

#endif

int omap_dm_timer_trigger(struct omap_dm_timer *timer)
{
	if (unlikely(!timer || pm_runtime_suspended(&timer->pdev->dev))) {
		pr_err("%s: timer not available or enabled.\n", __func__);
		return -EINVAL;
	}

	omap_dm_timer_write_reg(timer, OMAP_TIMER_TRIGGER_REG, 0);
	return 0;
}
EXPORT_SYMBOL_GPL(omap_dm_timer_trigger);

int omap_dm_timer_start(struct omap_dm_timer *timer)
{
	u32 l;

	if (unlikely(!timer))
		return -EINVAL;

	omap_dm_timer_enable(timer);

	if (!(timer->capability & OMAP_TIMER_ALWON)) {
		if (timer->get_context_loss_count &&
			timer->get_context_loss_count(&timer->pdev->dev) !=
				timer->ctx_loss_count)
			omap_timer_restore_context(timer);
	}

	l = omap_dm_timer_read_reg(timer, OMAP_TIMER_CTRL_REG);
	if (!(l & OMAP_TIMER_CTRL_ST)) {
		l |= OMAP_TIMER_CTRL_ST;
		omap_dm_timer_write_reg(timer, OMAP_TIMER_CTRL_REG, l);
	}

	/* Save the context */
	timer->context.tclr = l;
	return 0;
}
EXPORT_SYMBOL_GPL(omap_dm_timer_start);

int omap_dm_timer_stop(struct omap_dm_timer *timer)
{
	unsigned long rate = 0;

	if (unlikely(!timer))
		return -EINVAL;

	if (!(timer->capability & OMAP_TIMER_NEEDS_RESET))
		rate = clk_get_rate(timer->fclk);

	__omap_dm_timer_stop(timer, timer->posted, rate);

	if (!(timer->capability & OMAP_TIMER_ALWON)) {
		if (timer->get_context_loss_count)
			timer->ctx_loss_count =
				timer->get_context_loss_count(&timer->pdev->dev);
	}

	/*
	 * Since the register values are computed and written within
	 * __omap_dm_timer_stop, we need to use read to retrieve the
	 * context.
	 */
	timer->context.tclr =
			omap_dm_timer_read_reg(timer, OMAP_TIMER_CTRL_REG);
	timer->context.tisr = __raw_readl(timer->irq_stat);
	omap_dm_timer_disable(timer);
	return 0;
}
EXPORT_SYMBOL_GPL(omap_dm_timer_stop);

int omap_dm_timer_set_source(struct omap_dm_timer *timer, int source)
{
	int ret;
	char *parent_name = NULL;
	struct clk *fclk, *parent;
	struct dmtimer_platform_data *pdata;

	if (unlikely(!timer))
		return -EINVAL;

	pdata = timer->pdev->dev.platform_data;

	if (source < 0 || source >= 3)
		return -EINVAL;

	/*
	 * FIXME: Used for OMAP1 devices only because they do not currently
	 * use the clock framework to set the parent clock. To be removed
	 * once OMAP1 migrated to using clock framework for dmtimers
	 */
	if (pdata && pdata->set_timer_src)
		return pdata->set_timer_src(timer->pdev, source);

	fclk = clk_get(&timer->pdev->dev, "fck");
	if (IS_ERR_OR_NULL(fclk)) {
		pr_err("%s: fck not found\n", __func__);
		return -EINVAL;
	}

	switch (source) {
	case OMAP_TIMER_SRC_SYS_CLK:
		parent_name = "timer_sys_ck";
		break;

	case OMAP_TIMER_SRC_32_KHZ:
		parent_name = "timer_32k_ck";
		break;

	case OMAP_TIMER_SRC_EXT_CLK:
		parent_name = "timer_ext_ck";
		break;
	}

	parent = clk_get(&timer->pdev->dev, parent_name);
	if (IS_ERR_OR_NULL(parent)) {
		pr_err("%s: %s not found\n", __func__, parent_name);
		ret = -EINVAL;
		goto out;
	}

	ret = clk_set_parent(fclk, parent);
	if (IS_ERR_VALUE(ret))
		pr_err("%s: failed to set %s as parent\n", __func__,
			parent_name);

	clk_put(parent);
out:
	clk_put(fclk);

	return ret;
}
EXPORT_SYMBOL_GPL(omap_dm_timer_set_source);

int omap_dm_timer_set_load(struct omap_dm_timer *timer, int autoreload,
			    unsigned int load)
{
	u32 l;

	if (unlikely(!timer))
		return -EINVAL;

	omap_dm_timer_enable(timer);
	l = omap_dm_timer_read_reg(timer, OMAP_TIMER_CTRL_REG);
	if (autoreload)
		l |= OMAP_TIMER_CTRL_AR;
	else
		l &= ~OMAP_TIMER_CTRL_AR;
	omap_dm_timer_write_reg(timer, OMAP_TIMER_CTRL_REG, l);
	omap_dm_timer_write_reg(timer, OMAP_TIMER_LOAD_REG, load);

	omap_dm_timer_write_reg(timer, OMAP_TIMER_TRIGGER_REG, 0);
	/* Save the context */
	timer->context.tclr = l;
	timer->context.tldr = load;
	omap_dm_timer_disable(timer);
	return 0;
}
EXPORT_SYMBOL_GPL(omap_dm_timer_set_load);

/* Optimized set_load which removes costly spin wait in timer_start */
int omap_dm_timer_set_load_start(struct omap_dm_timer *timer, int autoreload,
                            unsigned int load)
{
	u32 l;

	if (unlikely(!timer))
		return -EINVAL;

	omap_dm_timer_enable(timer);

	if (!(timer->capability & OMAP_TIMER_ALWON)) {
		if (timer->get_context_loss_count &&
			timer->get_context_loss_count(&timer->pdev->dev) !=
				timer->ctx_loss_count)
			omap_timer_restore_context(timer);
	}

	l = omap_dm_timer_read_reg(timer, OMAP_TIMER_CTRL_REG);
	if (autoreload) {
		l |= OMAP_TIMER_CTRL_AR;
		omap_dm_timer_write_reg(timer, OMAP_TIMER_LOAD_REG, load);
	} else {
		l &= ~OMAP_TIMER_CTRL_AR;
	}
	l |= OMAP_TIMER_CTRL_ST;

	__omap_dm_timer_load_start(timer, l, load, timer->posted);

	/* Save the context */
	timer->context.tclr = l;
	timer->context.tldr = load;
	timer->context.tcrr = load;
	return 0;
}
EXPORT_SYMBOL_GPL(omap_dm_timer_set_load_start);

int omap_dm_timer_set_match(struct omap_dm_timer *timer, int enable,
			     unsigned int match)
{
	u32 l;

	if (unlikely(!timer))
		return -EINVAL;

	omap_dm_timer_enable(timer);
	l = omap_dm_timer_read_reg(timer, OMAP_TIMER_CTRL_REG);
	if (enable)
		l |= OMAP_TIMER_CTRL_CE;
	else
		l &= ~OMAP_TIMER_CTRL_CE;
	omap_dm_timer_write_reg(timer, OMAP_TIMER_CTRL_REG, l);
	omap_dm_timer_write_reg(timer, OMAP_TIMER_MATCH_REG, match);

	/* Save the context */
	timer->context.tclr = l;
	timer->context.tmar = match;
	omap_dm_timer_disable(timer);
	return 0;
}
EXPORT_SYMBOL_GPL(omap_dm_timer_set_match);

int omap_dm_timer_set_pwm(struct omap_dm_timer *timer, int def_on,
			   int toggle, int trigger)
{
	u32 l;

	if (unlikely(!timer))
		return -EINVAL;

	omap_dm_timer_enable(timer);
	l = omap_dm_timer_read_reg(timer, OMAP_TIMER_CTRL_REG);
	l &= ~(OMAP_TIMER_CTRL_GPOCFG | OMAP_TIMER_CTRL_SCPWM |
	       OMAP_TIMER_CTRL_PT | (0x03 << 10));
	if (def_on)
		l |= OMAP_TIMER_CTRL_SCPWM;
	if (toggle)
		l |= OMAP_TIMER_CTRL_PT;
	l |= trigger << 10;
	omap_dm_timer_write_reg(timer, OMAP_TIMER_CTRL_REG, l);

	/* Save the context */
	timer->context.tclr = l;
	omap_dm_timer_disable(timer);
	return 0;
}
EXPORT_SYMBOL_GPL(omap_dm_timer_set_pwm);

int omap_dm_timer_set_prescaler(struct omap_dm_timer *timer, int prescaler)
{
	u32 l;

	if (unlikely(!timer))
		return -EINVAL;

	omap_dm_timer_enable(timer);
	l = omap_dm_timer_read_reg(timer, OMAP_TIMER_CTRL_REG);
	l &= ~(OMAP_TIMER_CTRL_PRE | (0x07 << 2));
	if (prescaler >= 0x00 && prescaler <= 0x07) {
		l |= OMAP_TIMER_CTRL_PRE;
		l |= prescaler << 2;
	}
	omap_dm_timer_write_reg(timer, OMAP_TIMER_CTRL_REG, l);

	/* Save the context */
	timer->context.tclr = l;
	omap_dm_timer_disable(timer);
	return 0;
}
EXPORT_SYMBOL_GPL(omap_dm_timer_set_prescaler);

int omap_dm_timer_set_int_enable(struct omap_dm_timer *timer,
				  unsigned int value)
{
	if (unlikely(!timer))
		return -EINVAL;

	omap_dm_timer_enable(timer);
	__omap_dm_timer_int_enable(timer, value);

	/* Save the context */
	timer->context.tier = value;
	timer->context.twer = value;
	omap_dm_timer_disable(timer);
	return 0;
}
EXPORT_SYMBOL_GPL(omap_dm_timer_set_int_enable);

unsigned int omap_dm_timer_read_status(struct omap_dm_timer *timer)
{
	unsigned int l;

	if (unlikely(!timer || pm_runtime_suspended(&timer->pdev->dev))) {
		pr_err("%s: timer not available or enabled.\n", __func__);
		return 0;
	}

	l = __raw_readl(timer->irq_stat);

	return l;
}
EXPORT_SYMBOL_GPL(omap_dm_timer_read_status);

int omap_dm_timer_write_status(struct omap_dm_timer *timer, unsigned int value)
{
	if (unlikely(!timer || pm_runtime_suspended(&timer->pdev->dev)))
		return -EINVAL;

	__omap_dm_timer_write_status(timer, value);
	/* Save the context */
	timer->context.tisr = value;
	return 0;
}
EXPORT_SYMBOL_GPL(omap_dm_timer_write_status);

unsigned int omap_dm_timer_read_counter(struct omap_dm_timer *timer)
{
	if (unlikely(!timer || pm_runtime_suspended(&timer->pdev->dev))) {
		pr_err("%s: timer not iavailable or enabled.\n", __func__);
		return 0;
	}

	return __omap_dm_timer_read_counter(timer, timer->posted);
}
EXPORT_SYMBOL_GPL(omap_dm_timer_read_counter);

int omap_dm_timer_write_counter(struct omap_dm_timer *timer, unsigned int value)
{
	if (unlikely(!timer || pm_runtime_suspended(&timer->pdev->dev))) {
		pr_err("%s: timer not available or enabled.\n", __func__);
		return -EINVAL;
	}

	omap_dm_timer_write_reg(timer, OMAP_TIMER_COUNTER_REG, value);

	/* Save the context */
	timer->context.tcrr = value;
	return 0;
}
EXPORT_SYMBOL_GPL(omap_dm_timer_write_counter);

int omap_dm_timers_active(void)
{
	struct omap_dm_timer *timer;

	list_for_each_entry(timer, &omap_timer_list, node) {
		if (!timer->reserved)
			continue;

		if (omap_dm_timer_read_reg(timer, OMAP_TIMER_CTRL_REG) &
		    OMAP_TIMER_CTRL_ST) {
			return 1;
		}
	}
	return 0;
}
EXPORT_SYMBOL_GPL(omap_dm_timers_active);

/**
 * omap_dm_timer_probe - probe function called for every registered device
 * @pdev:	pointer to current timer platform device
 *
 * Called by driver framework at the end of device registration for all
 * timer devices.
 */
static int __devinit omap_dm_timer_probe(struct platform_device *pdev)
{
	unsigned long flags;
	struct omap_dm_timer *timer;
	struct resource *mem, *irq;
	struct device *dev = &pdev->dev;
	struct dmtimer_platform_data *pdata = pdev->dev.platform_data;

	if (!pdata && !dev->of_node) {
		dev_err(dev, "%s: no platform data.\n", __func__);
		return -ENODEV;
	}

	irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
	if (unlikely(!irq)) {
		dev_err(dev, "%s: no IRQ resource.\n", __func__);
		return -ENODEV;
	}

	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	if (unlikely(!mem)) {
		dev_err(dev, "%s: no memory resource.\n", __func__);
		return -ENODEV;
	}

	timer = devm_kzalloc(dev, sizeof(struct omap_dm_timer), GFP_KERNEL);
	if (!timer) {
		dev_err(dev, "%s: memory alloc failed!\n", __func__);
		return  -ENOMEM;
	}

	timer->io_base = devm_request_and_ioremap(dev, mem);
	if (!timer->io_base) {
		dev_err(dev, "%s: region already claimed.\n", __func__);
		return -ENOMEM;
	}

	if (dev->of_node) {
		if (of_find_property(dev->of_node, "ti,timer-alwon", NULL))
			timer->capability |= OMAP_TIMER_ALWON;
		if (of_find_property(dev->of_node, "ti,timer-dsp", NULL))
			timer->capability |= OMAP_TIMER_HAS_DSP_IRQ;
		if (of_find_property(dev->of_node, "ti,timer-pwm", NULL))
			timer->capability |= OMAP_TIMER_HAS_PWM;
		if (of_find_property(dev->of_node, "ti,timer-secure", NULL))
			timer->capability |= OMAP_TIMER_SECURE;
	} else {
		timer->id = pdev->id;
		timer->errata = pdata->timer_errata;
		timer->capability = pdata->timer_capability;
		timer->reserved = omap_dm_timer_reserved_systimer(timer->id);
		timer->get_context_loss_count = pdata->get_context_loss_count;
	}

	timer->irq = irq->start;
	timer->pdev = pdev;

	/* Skip pm_runtime_enable for OMAP1 */
	if (!(timer->capability & OMAP_TIMER_NEEDS_RESET)) {
		pm_runtime_enable(dev);
		pm_runtime_irq_safe(dev);
	}

	if (!timer->reserved) {
		pm_runtime_get_sync(dev);
		__omap_dm_timer_init_regs(timer);
		pm_runtime_put(dev);
	}

	/* add the timer element to the list */
	spin_lock_irqsave(&dm_timer_lock, flags);
	list_add_tail(&timer->node, &omap_timer_list);
	spin_unlock_irqrestore(&dm_timer_lock, flags);

	dev_dbg(dev, "Device Probed.\n");

	return 0;
}

/**
 * omap_dm_timer_remove - cleanup a registered timer device
 * @pdev:	pointer to current timer platform device
 *
 * Called by driver framework whenever a timer device is unregistered.
 * In addition to freeing platform resources it also deletes the timer
 * entry from the local list.
 */
static int __devexit omap_dm_timer_remove(struct platform_device *pdev)
{
	struct omap_dm_timer *timer;
	unsigned long flags;
	int ret = -EINVAL;

	spin_lock_irqsave(&dm_timer_lock, flags);
	list_for_each_entry(timer, &omap_timer_list, node)
		if (!strcmp(dev_name(&timer->pdev->dev),
			    dev_name(&pdev->dev))) {
			list_del(&timer->node);
			ret = 0;
			break;
		}
	spin_unlock_irqrestore(&dm_timer_lock, flags);

	return ret;
}

static const struct of_device_id omap_timer_match[] = {
	{ .compatible = "ti,omap2-timer", },
	{},
};
MODULE_DEVICE_TABLE(of, omap_timer_match);

static struct platform_driver omap_dm_timer_driver = {
	.probe  = omap_dm_timer_probe,
	.remove = __devexit_p(omap_dm_timer_remove),
	.driver = {
		.name   = "omap_timer",
		.of_match_table = of_match_ptr(omap_timer_match),
	},
};

static int __init omap_dm_timer_driver_init(void)
{
	return platform_driver_register(&omap_dm_timer_driver);
}

static void __exit omap_dm_timer_driver_exit(void)
{
	platform_driver_unregister(&omap_dm_timer_driver);
}

early_platform_init("earlytimer", &omap_dm_timer_driver);
module_init(omap_dm_timer_driver_init);
module_exit(omap_dm_timer_driver_exit);

MODULE_DESCRIPTION("OMAP Dual-Mode Timer Driver");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:" DRIVER_NAME);
MODULE_AUTHOR("Texas Instruments Inc");