summaryrefslogtreecommitdiff
path: root/target/linux/ep93xx/patches-3.10/003-ep93xx_touchscreen.patch
blob: cbc5248f8c8a46a74d04335d7f473094f82a70e9 (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
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
---
 arch/arm/mach-ep93xx/include/mach/hardware.h   |    1 
 arch/arm/mach-ep93xx/include/mach/regs_touch.h |   95 ++
 drivers/input/touchscreen/Kconfig              |    5 
 drivers/input/touchscreen/Makefile             |    1 
 drivers/input/touchscreen/ep93xx_ts.c          | 1117 +++++++++++++++++++++++++
 drivers/input/touchscreen/ep93xx_ts.h          |   53 +
 6 files changed, 1272 insertions(+)

--- a/drivers/input/touchscreen/Kconfig
+++ b/drivers/input/touchscreen/Kconfig
@@ -235,6 +235,15 @@ config TOUCHSCREEN_EGALAX
 	  To compile this driver as a module, choose M here: the
 	  module will be called egalax_ts.
 
+config TOUCHSCREEN_EP93XX
+	tristate "EP93xx Touchscreen"
+	depends on ARM && INPUT && ARCH_EP93XX
+	help
+	  Say Y here to enable support for EP93xx touch screen.
+
+	  To compile this driver as a module, choose M here:
+	  the module will be called ep93xx_ts.
+
 config TOUCHSCREEN_FUJITSU
 	tristate "Fujitsu serial touchscreen"
 	select SERIO
--- a/drivers/input/touchscreen/Makefile
+++ b/drivers/input/touchscreen/Makefile
@@ -29,6 +29,7 @@ obj-$(CONFIG_TOUCHSCREEN_GUNZE)		+= gunz
 obj-$(CONFIG_TOUCHSCREEN_EETI)		+= eeti_ts.o
 obj-$(CONFIG_TOUCHSCREEN_ELO)		+= elo.o
 obj-$(CONFIG_TOUCHSCREEN_EGALAX)	+= egalax_ts.o
+obj-$(CONFIG_TOUCHSCREEN_EP93XX)	+= ep93xx_ts.o
 obj-$(CONFIG_TOUCHSCREEN_FUJITSU)	+= fujitsu_ts.o
 obj-$(CONFIG_TOUCHSCREEN_ILI210X)	+= ili210x.o
 obj-$(CONFIG_TOUCHSCREEN_INEXIO)	+= inexio.o
--- /dev/null
+++ b/drivers/input/touchscreen/ep93xx_ts.c
@@ -0,0 +1,1022 @@
+/*
+ * linux/drivers/input/touchscreen/ep93xx_ts.c
+ *
+ * Copyright (C) 2003-2004 Cirrus Corp.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/delay.h>
+#include <linux/wait.h>
+#include <linux/fs.h>
+#include <linux/sched.h>
+#include <linux/poll.h>
+#include <linux/miscdevice.h>
+#include <linux/init.h>
+#include <linux/compiler.h>
+#include <linux/timer.h>
+#include <linux/interrupt.h>
+#include <linux/syscalls.h>
+#include <linux/input.h>
+#include <linux/semaphore.h>
+#include <asm/irq.h>
+#include <mach/hardware.h>
+#include <asm/io.h>
+#include "../../../arch/arm/mach-ep93xx/soc.h"
+
+/* This stuff should be in ep93xx-regs.h */
+#define EP93XX_TOUCHSCREEN_REG(x)	(EP93XX_TOUCHSCREEN_BASE + (x))
+/* R/W touchscreen controller setup control register. */
+#define EP93XX_TOUCHSCREEN_SETUP	EP93XX_TOUCHSCREEN_REG(0x00)
+/* R/W touchscreen controller max/min register. */
+#define EP93XX_TOUCHSCREEN_XYMAXMIN	EP93XX_TOUCHSCREEN_REG(0x04)
+/* R   touchscreen controller result register. */
+#define EP93XX_TOUCHSCREEN_XYRESULT	EP93XX_TOUCHSCREEN_REG(0x08)
+/* LOCKED R/W touchscreen Switch Matrix control register. */
+#define EP93XX_TOUCHSCREEN_DISCHARGE	EP93XX_TOUCHSCREEN_REG(0x0C)
+#define EP93XX_TOUCHSCREEN_XSAMPLE	EP93XX_TOUCHSCREEN_REG(0x10)
+#define EP93XX_TOUCHSCREEN_YSAMPLE	EP93XX_TOUCHSCREEN_REG(0x14)
+#define EP93XX_TOUCHSCREEN_DIRECT	EP93XX_TOUCHSCREEN_REG(0x18)
+#define EP93XX_TOUCHSCREEN_DETECT	EP93XX_TOUCHSCREEN_REG(0x1C)
+/*  NA    R/W touchscreen software lock register. */
+#define EP93XX_TOUCHSCREEN_SWLOCK	EP93XX_TOUCHSCREEN_REG(0x20)
+/* R/W touchscreen setup control register #2. */
+#define EP93XX_TOUCHSCREEN_SETUP2	EP93XX_TOUCHSCREEN_REG(0x24)
+
+/* These are duplicated in mach-ep93xx/core.c */
+#define EP93XX_TIMER_REG(x)	(EP93XX_TIMER_BASE + (x))
+#define EP93XX_TIMER2_LOAD	EP93XX_TIMER_REG(0x20)
+#define EP93XX_TIMER2_VALUE	EP93XX_TIMER_REG(0x24)
+#define EP93XX_TIMER2_CONTROL	EP93XX_TIMER_REG(0x28)
+#define EP93XX_TIMER2_CLEAR	EP93XX_TIMER_REG(0x2c)
+
+/*
+ * Register bit definitions
+ */
+#define TSSETUP_SDLY_MASK	0x000003FF
+#define TSSETUP_SDLY_SHIFT	0
+#define TSSETUP_NSMP_4		0x00000000
+#define TSSETUP_NSMP_8		0x00000400
+#define TSSETUP_NSMP_16		0x00000800
+#define TSSETUP_NSMP_32		0x00000C00
+#define TSSETUP_NSMP_MASK	0x00000C00
+#define TSSETUP_DEV_4		0x00000000
+#define TSSETUP_DEV_8		0x00001000
+#define TSSETUP_DEV_12		0x00002000
+#define TSSETUP_DEV_16		0x00003000
+#define TSSETUP_DEV_24		0x00004000
+#define TSSETUP_DEV_32		0x00005000
+#define TSSETUP_DEV_64		0x00006000
+#define TSSETUP_DEV_128		0x00007000
+#define TSSETUP_ENABLE		0x00008000
+#define TSSETUP_DLY_MASK	0x03FF0000
+#define TSSETUP_DLY_SHIFT	16
+#define TSSETUP_TDTCT		0x80000000
+
+#define TSMAXMIN_XMIN_MASK	0x000000FF
+#define TSMAXMIN_XMIN_SHIFT	0
+#define TSMAXMIN_YMIN_MASK	0x0000FF00
+#define TSMAXMIN_YMIN_SHIFT	8
+#define TSMAXMIN_XMAX_MASK	0x00FF0000
+#define TSMAXMIN_XMAX_SHIFT	16
+#define TSMAXMIN_YMAX_MASK	0xFF000000
+#define TSMAXMIN_YMAX_SHIFT	24
+
+#define TSXYRESULT_X_MASK	0x00000FFF
+#define TSXYRESULT_X_SHIFT	0
+#define TSXYRESULT_AD_MASK	0x0000FFFF
+#define TSXYRESULT_AD_SHIFT	0
+#define TSXYRESULT_Y_MASK	0x0FFF0000
+#define TSXYRESULT_Y_SHIFT	16
+#define TSXYRESULT_SDR		0x80000000
+
+#define TSX_SAMPLE_MASK		0x00003FFF
+#define TSX_SAMPLE_SHIFT	0x00
+#define TSY_SAMPLE_MASK		0x3FFF0000
+#define TSY_SAMPLE_SHIFT	0x10
+
+#define TSSETUP2_TINT		0x00000001
+#define TSSETUP2_NICOR		0x00000002
+#define TSSETUP2_PINT		0x00000004
+#define TSSETUP2_PENSTS		0x00000008
+#define TSSETUP2_PINTEN		0x00000010
+#define TSSETUP2_DEVINT		0x00000020
+#define TSSETUP2_DINTEN		0x00000040
+#define TSSETUP2_DTMEN		0x00000080
+#define TSSETUP2_DISDEV		0x00000100
+#define TSSETUP2_NSIGND		0x00000200
+#define TSSETUP2_S28EN		0x00000400
+#define TSSETUP2_RINTEN		0x00000800
+
+#define TSXYRESULT_SDR		0x80000000
+
+/*
+ * These are used as trigger levels to know when we have pen up/down.
+ * The rules:
+ * 1.  TS_HEAVY_INV_PRESSURE < TS_LIGHT_INV_PRESSURE because these
+ *    are Inverse pressure.
+ * 2.  Any touch lighter than TS_LIGHT_INV_PRESSURE is a pen up.
+ * 3.  Any touch heavier than TS_HEAVY_INV_PRESSURE is a pen down.
+ */
+#define TS_HEAVY_INV_PRESSURE 0xFE0 /* C00 */
+#define TS_LIGHT_INV_PRESSURE 0xFFF /* e00 */
+
+/*
+ * If the x, y, or inverse pressure changes more than these values
+ * between two succeeding points, the point is not reported.
+ */
+#define TS_MAX_VALID_XY_CHANGE		0x300
+#define TS_MAX_VALID_PRESSURE_CHANGE	0x100
+
+/*
+ * This is the minimum Z1 Value that is valid.
+ */
+#define MIN_Z1_VALUE 0x50
+
+/*
+ * Settling delay for taking each ADC measurement.  Increase this
+ * if ts is jittery.
+ */
+#define EP93XX_TS_ADC_DELAY_USEC 2000
+
+/*
+ * Delay between TS points.
+ */
+#define EP93XX_TS_PER_POINT_DELAY_USEC 10000
+
+/*
+ * A few more macros...
+ */
+#define TSSETUP_DEFAULT  (TSSETUP_NSMP_32 | TSSETUP_DEV_64 |  \
+			  ((128<<TSSETUP_SDLY_SHIFT) & TSSETUP_SDLY_MASK) | \
+			  ((128<<TSSETUP_DLY_SHIFT)  & TSSETUP_DLY_MASK))
+
+#define TSSETUP2_DEFAULT (TSSETUP2_NSIGND)
+
+/*
+ * For now, we use one of the minor numbers from the local/experimental
+ * range.
+ */
+#define EP93XX_TS_MINOR 240
+
+/*
+ * Static Declarations
+ */
+static unsigned int   guiLastX, guiLastY;
+static unsigned int   guiLastInvPressure;
+
+struct TouchScreenSample
+{
+    int currentX;
+    int currentY;
+    int currentButton;
+    int currentPressure;
+    struct timeval currentTime;
+};
+
+/*
+ * This must match the structure in tslib.
+ */
+struct ts_sample {
+    int x;
+    int y;
+    unsigned int pressure;
+    struct timeval tv;
+};
+
+static struct TouchScreenSample gSample;
+static int bFreshTouchData;
+static int bCurrentPenDown;
+
+static DECLARE_WAIT_QUEUE_HEAD(queue);
+static DEFINE_SEMAPHORE(open_sem);
+static DEFINE_SPINLOCK(event_buffer_lock);
+static struct fasync_struct *ep93xx_fasync;
+
+/*
+ * Typedef Declarations
+ */
+typedef enum {
+    TS_MODE_UN_INITIALIZED,
+    TS_MODE_HARDWARE_SCAN,
+    TS_MODE_SOFT_SCAN
+} ts_mode_t;
+
+static ts_mode_t gScanningMode;
+
+typedef enum{
+    TS_STATE_STOPPED = 0,
+    TS_STATE_Z1,
+    TS_STATE_Z2,
+    TS_STATE_Y,
+    TS_STATE_X,
+    TS_STATE_DONE
+} ts_states_t;
+
+typedef struct
+{
+    unsigned int uiX;
+    unsigned int uiY;
+    unsigned int uiZ1;
+    unsigned int uiZ2;
+    ts_states_t  state;
+} ts_struct_t;
+
+static ts_struct_t sTouch;
+
+/*
+ * From the spec, here's how to set up the touch screen's switch registers.
+ */
+typedef struct
+{
+    unsigned int uiDetect;
+    unsigned int uiDischarge;
+    unsigned int uiXSample;
+    unsigned int uiYSample;
+    unsigned int uiSwitchZ1;
+    unsigned int uiSwitchZ2;
+}SwitchStructType;
+
+/*
+ * Here's the switch settings for a 4-wire touchscreen.  See the spec
+ * for how to handle a 4, 7, or 8-wire.
+ */
+const static SwitchStructType sSwitchSettings =
+/* s28en=0 */
+/*   TSDetect    TSDischarge TSXSample   TSYSample   SwitchZ1    SwitchZ2 */
+    {0x00403604, 0x0007fe04, 0x00081604, 0x00104601, 0x00101601, 0x00101608};
+
+/*
+ * Function declarations
+ */
+static void ep93xx_ts_set_direct(unsigned int uiADCSwitch);
+static irqreturn_t ep93xx_ts_isr(int irq, void *dev_id);
+static irqreturn_t ep93xx_timer2_isr(int irq, void *dev_id);
+static void ee93xx_ts_evt_add(int button, int dX, int dY, int Pressure);
+static ssize_t ep93xx_ts_read(struct file *filp, char *buf,
+	size_t count, loff_t *l);
+static unsigned int ep93xx_ts_poll(struct file *filp, poll_table *wait);
+static int ep93xx_ts_open(struct inode *inode, struct file *filp);
+static int ep93xx_ts_fasync(int fd, struct file *filp, int on);
+static int ep93xx_ts_release(struct inode *inode, struct file *filp);
+static ssize_t ep93xx_ts_write(struct file *file, const char *buffer,
+		size_t count, loff_t *ppos);
+static void ep93xx_ts_setup(void);
+static void ep93xx_ts_shutdown(void);
+int __init ep93xx_ts_init(void);
+void __exit ep93xx_ts_exit(void);
+static unsigned int CalculateInvPressure(void);
+static unsigned int ADCGetData(unsigned int uiSamples, unsigned int uiMaxDiff);
+static void TS_Soft_Scan_Mode(void);
+static void TS_Hardware_Scan_Mode(void);
+static void ProcessPointData(void);
+static void Set_Timer2_uSec(unsigned int Delay_mSec);
+static void Stop_Timer2(void);
+
+/*
+ *  ep93xx_ts_isr
+ */
+static irqreturn_t ep93xx_ts_isr(int irq, void *dev_id)
+{
+    /*
+     * Note that we don't clear the interrupt here.  The interrupt
+     * gets cleared in TS_Soft_Scan_Mode when the TS ENABLE
+     * bit is cleared.
+     */
+
+    /*
+     * Set the ts to manual polling mode and schedule a callback.
+     * That way we can return from the isr in a reasonable amount of
+     * time and process the touch in the callback after a brief delay.
+     */
+    TS_Soft_Scan_Mode();
+
+    return(IRQ_HANDLED);
+}
+
+/*
+ * Save the current ts 'event' in an atomic fashion.
+ */
+static void ee93xx_ts_evt_add(int buttons, int iX, int iY, int iPressure)
+{
+    /*
+     * Note the event, but use spinlocks to keep it from getting
+     * halfway read if we get interrupted.
+     */
+
+    spin_lock(&event_buffer_lock);
+
+    gSample.currentX        = iX;
+    gSample.currentY        = iY;
+    gSample.currentButton   = buttons;
+    gSample.currentPressure = iPressure;
+    bFreshTouchData         = 1;
+    do_gettimeofday(&gSample.currentTime);
+
+    spin_unlock(&event_buffer_lock);
+
+    kill_fasync(&ep93xx_fasync, SIGIO, POLL_IN);
+    wake_up_interruptible(&queue);
+}
+
+
+static ssize_t ep93xx_ts_read(struct file *filp, char *buf, size_t count, loff_t *l)
+{
+    unsigned short data[3];
+    struct  ts_sample   ts_data;
+    int     iReturn = -EFAULT;
+
+    if (!bFreshTouchData)
+    {
+	iReturn = 0;
+    }
+    else if (count == sizeof(data))
+    {
+	spin_lock_irq(&event_buffer_lock);
+	bFreshTouchData = 0;
+	data[0] = gSample.currentX;
+	data[1] = gSample.currentY;
+	data[2] = gSample.currentButton;
+
+	spin_unlock_irq(&event_buffer_lock);
+
+	if (copy_to_user(buf, data, sizeof data))
+	    return -EFAULT;
+
+	count -= sizeof(data);
+
+	/* return the # of bytes that got read */
+	iReturn = sizeof(data) ;
+    }
+    else if (count == sizeof(struct ts_sample) )
+    {
+	spin_lock_irq(&event_buffer_lock);
+	bFreshTouchData = 0;
+	ts_data.x           = gSample.currentX;
+	ts_data.y           = gSample.currentY;
+	ts_data.pressure    = gSample.currentPressure;
+	ts_data.tv          = gSample.currentTime;
+	spin_unlock_irq(&event_buffer_lock);
+
+	if (copy_to_user(buf, &ts_data, sizeof(struct ts_sample)))
+	{
+	    iReturn = -EFAULT;
+	}
+	else
+	{
+	    count -= sizeof(ts_data);
+	    iReturn = sizeof(ts_data);
+	}
+    }
+
+    return iReturn;
+}
+
+static unsigned int ep93xx_ts_poll(struct file *filp, poll_table *wait)
+{
+    poll_wait(filp, &queue, wait);
+
+    if (bFreshTouchData)
+    {
+	return POLLIN | POLLRDNORM;
+    }
+
+    return 0;
+}
+
+static int ep93xx_ts_open(struct inode *inode, struct file *filp)
+{
+    if (down_trylock(&open_sem))
+    {
+	return -EBUSY;
+    }
+
+    ep93xx_ts_setup();
+
+    return 0;
+}
+
+/*
+ * Asynchronous I/O support.
+ */
+static int ep93xx_ts_fasync(int fd, struct file *filp, int on)
+{
+    int retval;
+
+    retval = fasync_helper(fd, filp, on, &ep93xx_fasync);
+    if (retval < 0)
+    {
+	return retval;
+    }
+
+    return 0;
+}
+
+static int ep93xx_ts_release(struct inode *inode, struct file *filp)
+{
+    Stop_Timer2();
+
+    /*
+     * Call our async I/O support to request that this file
+     * cease to be used for async I/O.
+     */
+    ep93xx_ts_fasync(-1, filp, 0);
+
+    ep93xx_ts_shutdown();
+
+    up(&open_sem);
+
+    return 0;
+}
+
+static ssize_t ep93xx_ts_write(struct file *file, const char *buffer, size_t count,
+	       loff_t *ppos)
+{
+    return -EINVAL;
+}
+
+
+static int ep93xx_ts_ioctl(struct inode *inode, struct file *file, uint command, ulong u)
+{
+    static const int         version = EV_VERSION;
+    static const u_int32_t   bit =(1 << EV_ABS);
+    static const u_int32_t   absbit = (1 << ABS_X) | (1 << ABS_Y) | (1 << ABS_PRESSURE);
+    int         iReturn ;
+    int         i = 0;
+
+    switch(command)
+    {
+	case EVIOCGVERSION:
+	    i = copy_to_user((void __user *)u, (void *)version, sizeof(version));
+	    iReturn = i ? -EFAULT : 0;
+	    break;
+
+	case EVIOCGBIT(0,sizeof(u_int32_t) * 8) :
+	    i = copy_to_user((void __user *)u, (void *)bit, sizeof(bit));
+	    iReturn = i ? -EFAULT : 0;
+	    break;
+
+	case EVIOCGBIT(EV_ABS, sizeof(absbit) * 8):
+	    i = copy_to_user((void __user *)u, (void *)absbit, sizeof(absbit));
+	    iReturn = i ? -EFAULT : 0;
+	    break;
+	default:
+	    iReturn = -1;
+	    break;
+    }
+
+    return iReturn;
+}
+
+static struct file_operations ep93xx_ts_fops = {
+    owner:      THIS_MODULE,
+    read:       ep93xx_ts_read,
+    write:      ep93xx_ts_write,
+    poll:       ep93xx_ts_poll,
+    open:       ep93xx_ts_open,
+    unlocked_ioctl:      ep93xx_ts_ioctl,
+    release:    ep93xx_ts_release,
+    fasync:     ep93xx_ts_fasync,
+};
+
+static struct miscdevice ep93xx_ts_miscdev =
+{
+	EP93XX_TS_MINOR,
+	"ep93xx_ts",
+	&ep93xx_ts_fops
+};
+
+void ep93xx_ts_setup(void)
+{
+    unsigned int uiKTDIV, uiTSXYMaxMin;
+
+    /*
+     * Set the TSEN bit in KTDIV so that we are enabling the clock
+     * for the touchscreen.
+     */
+    uiKTDIV = __raw_readl(EP93XX_SYSCON_KEYTCHCLKDIV);
+    uiKTDIV |= EP93XX_SYSCON_KEYTCHCLKDIV_TSEN;
+    ep93xx_syscon_swlocked_write(uiKTDIV, EP93XX_SYSCON_KEYTCHCLKDIV);
+
+    /*
+     * Program the EP93XX_TOUCHSCREEN_SETUP and TSSetup2 registers.
+     */
+    __raw_writel(TSSETUP_DEFAULT, EP93XX_TOUCHSCREEN_SETUP);
+    __raw_writel(TSSETUP2_DEFAULT, EP93XX_TOUCHSCREEN_SETUP2);
+
+    /*
+     * Set the the touch settings.
+     */
+    __raw_writel(0xaa, EP93XX_TOUCHSCREEN_SWLOCK);
+    __raw_writel(sSwitchSettings.uiDischarge, EP93XX_TOUCHSCREEN_DIRECT);
+
+    __raw_writel(0xaa, EP93XX_TOUCHSCREEN_SWLOCK);
+    __raw_writel(sSwitchSettings.uiDischarge, EP93XX_TOUCHSCREEN_DISCHARGE);
+
+    __raw_writel(0xaa, EP93XX_TOUCHSCREEN_SWLOCK);
+    __raw_writel(sSwitchSettings.uiSwitchZ1, EP93XX_TOUCHSCREEN_XSAMPLE);
+
+    __raw_writel(0xaa, EP93XX_TOUCHSCREEN_SWLOCK);
+    __raw_writel(sSwitchSettings.uiSwitchZ2, EP93XX_TOUCHSCREEN_YSAMPLE);
+
+    __raw_writel(0xaa, EP93XX_TOUCHSCREEN_SWLOCK);
+    __raw_writel(sSwitchSettings.uiDetect, EP93XX_TOUCHSCREEN_DETECT);
+
+    /*
+     * X,YMin set to 0x40 = have to drag that many pixels for a new irq.
+     * X,YMax set to 0x40 = 1024 pixels is the maximum movement within the
+     * time scan limit.
+     */
+    uiTSXYMaxMin =  (50   << TSMAXMIN_XMIN_SHIFT) & TSMAXMIN_XMIN_MASK;
+    uiTSXYMaxMin |= (50   << TSMAXMIN_YMIN_SHIFT) & TSMAXMIN_YMIN_MASK;
+    uiTSXYMaxMin |= (0xff << TSMAXMIN_XMAX_SHIFT) & TSMAXMIN_XMAX_MASK;
+    uiTSXYMaxMin |= (0xff << TSMAXMIN_YMAX_SHIFT) & TSMAXMIN_YMAX_MASK;
+    __raw_writel(uiTSXYMaxMin, EP93XX_TOUCHSCREEN_XYMAXMIN);
+
+    bCurrentPenDown = 0;
+    bFreshTouchData = 0;
+    guiLastX = 0;
+    guiLastY = 0;
+    guiLastInvPressure = 0xffffff;
+
+    /*
+     * Enable the touch screen scanning engine.
+     */
+    TS_Hardware_Scan_Mode();
+}
+
+/*
+ * ep93xx_ts_shutdown
+ *
+ */
+static void
+ep93xx_ts_shutdown(void)
+{
+    unsigned int uiKTDIV;
+
+    sTouch.state = TS_STATE_STOPPED;
+    Stop_Timer2();
+
+    /*
+     * Disable the scanning engine.
+     */
+    __raw_writel(0, EP93XX_TOUCHSCREEN_SETUP);
+    __raw_writel(0, EP93XX_TOUCHSCREEN_SETUP2);
+
+    /*
+     * Clear the TSEN bit in KTDIV so that we are disabling the clock
+     * for the touchscreen.
+     */
+    uiKTDIV = __raw_readl(EP93XX_SYSCON_KEYTCHCLKDIV);
+    uiKTDIV &= ~EP93XX_SYSCON_KEYTCHCLKDIV_TSEN;
+    ep93xx_syscon_swlocked_write(uiKTDIV, EP93XX_SYSCON_KEYTCHCLKDIV);
+
+} /* ep93xx_ts_shutdown */
+
+static irqreturn_t ep93xx_timer2_isr(int irq, void *dev_id)
+{
+    switch(sTouch.state)
+    {
+	case TS_STATE_STOPPED:
+	    TS_Hardware_Scan_Mode();
+	    break;
+
+	/*
+	 * Get the Z1 value for pressure measurement and set up
+	 * the switch register for getting the Z2 measurement.
+	 */
+	case TS_STATE_Z1:
+	    Set_Timer2_uSec(EP93XX_TS_ADC_DELAY_USEC);
+	    sTouch.uiZ1 = ADCGetData(2, 200);
+	    ep93xx_ts_set_direct(sSwitchSettings.uiSwitchZ2);
+	    sTouch.state = TS_STATE_Z2;
+	    break;
+
+	/*
+	 * Get the Z2 value for pressure measurement and set up
+	 * the switch register for getting the Y measurement.
+	 */
+	case TS_STATE_Z2:
+	    sTouch.uiZ2 = ADCGetData(2, 200);
+	    ep93xx_ts_set_direct(sSwitchSettings.uiYSample);
+	    sTouch.state = TS_STATE_Y;
+	    break;
+
+	/*
+	 * Get the Y value and set up the switch register for
+	 * getting the X measurement.
+	 */
+	case TS_STATE_Y:
+	    sTouch.uiY = ADCGetData(4, 20);
+	    ep93xx_ts_set_direct(sSwitchSettings.uiXSample);
+	    sTouch.state = TS_STATE_X;
+	    break;
+
+	/*
+	 * Read the X value.  This is the last of the 4 adc values
+	 * we need so we continue on to process the data.
+	 */
+	case TS_STATE_X:
+	    Stop_Timer2();
+
+	    sTouch.uiX = ADCGetData(4, 20);
+
+	    __raw_writel(0xaa, EP93XX_TOUCHSCREEN_SWLOCK);
+	    __raw_writel(sSwitchSettings.uiDischarge, EP93XX_TOUCHSCREEN_DIRECT);
+
+	    sTouch.state = TS_STATE_DONE;
+
+	    /*
+	     * Process this set of ADC readings.
+	     */
+	    ProcessPointData();
+
+	    break;
+
+	/*
+	 * Shouldn't get here.  But if we do, we can recover...
+	 */
+	case TS_STATE_DONE:
+	    TS_Hardware_Scan_Mode();
+	    break;
+    }
+
+    /*
+     * Clear the timer2 interrupt.
+     */
+    __raw_writel(1, EP93XX_TIMER2_CLEAR);
+    return(IRQ_HANDLED);
+}
+
+/*---------------------------------------------------------------------
+ * ProcessPointData
+ *
+ * This routine processes the ADC data into usable point data and then
+ * puts the driver into hw or sw scanning mode before returning.
+ *
+ * We calculate inverse pressure (lower number = more pressure) then
+ * do a hystheresis with the two pressure values 'light' and 'heavy'.
+ *
+ * If we are above the light, we have pen up.
+ * If we are below the heavy we have pen down.
+ * As long as the pressure stays below the light, pen stays down.
+ * When we get above the light again, pen goes back up.
+ *
+ */
+static void ProcessPointData(void)
+{
+    int  bValidPoint = 0;
+    unsigned int   uiXDiff, uiYDiff, uiInvPressureDiff;
+    unsigned int   uiInvPressure;
+
+    /*
+     * Calculate the current pressure.
+     */
+    uiInvPressure = CalculateInvPressure();
+
+    /*
+     * If pen pressure is so light that it is greater than the 'max' setting
+     * then we consider this to be a pen up.
+     */
+    if (uiInvPressure >= TS_LIGHT_INV_PRESSURE)
+    {
+	bCurrentPenDown = 0;
+	ee93xx_ts_evt_add(0, guiLastX, guiLastY, 0);
+	TS_Hardware_Scan_Mode();
+	return;
+    }
+
+    /*
+     * Hysteresis:
+     * If the pen pressure is hard enough to be less than the 'min' OR
+     * the pen is already down and is still less than the 'max'...
+     */
+    if ((uiInvPressure < TS_HEAVY_INV_PRESSURE) ||
+	(bCurrentPenDown && (uiInvPressure < TS_LIGHT_INV_PRESSURE)))
+    {
+	if (bCurrentPenDown)
+	{
+	    /*
+	     * If pen was previously down, check the difference between
+	     * the last sample and this one... if the difference between
+	     * samples is too great, ignore the sample.
+	     */
+	    uiXDiff = abs(guiLastX - sTouch.uiX);
+	    uiYDiff = abs(guiLastY - sTouch.uiY);
+	    uiInvPressureDiff = abs(guiLastInvPressure - uiInvPressure);
+
+	    if (uiXDiff < TS_MAX_VALID_XY_CHANGE
+		&& uiYDiff < TS_MAX_VALID_XY_CHANGE
+		&& uiInvPressureDiff < TS_MAX_VALID_PRESSURE_CHANGE)
+	    {
+		bValidPoint = 1;
+	    }
+	}
+	else
+	{
+	    bValidPoint = 1;
+	}
+
+	/*
+	 * If either the pen was put down or dragged make a note of it.
+	 */
+	if (bValidPoint)
+	{
+	    guiLastX = sTouch.uiX;
+	    guiLastY = sTouch.uiY;
+	    guiLastInvPressure = uiInvPressure;
+	    bCurrentPenDown = 1;
+	    ee93xx_ts_evt_add(1, sTouch.uiX, sTouch.uiY,
+			      0x7000000 / uiInvPressure);
+	}
+
+	TS_Soft_Scan_Mode();
+	return;
+    }
+
+    TS_Hardware_Scan_Mode();
+}
+
+static void ep93xx_ts_set_direct(unsigned int uiADCSwitch)
+{
+    unsigned int uiResult;
+
+    /*
+     * Set the switch settings in the direct register.
+     */
+    __raw_writel(0xaa, EP93XX_TOUCHSCREEN_SWLOCK);
+    __raw_writel(uiADCSwitch, EP93XX_TOUCHSCREEN_DIRECT);
+
+    /*
+     * Read and throw away the first sample.
+     */
+    do {
+	uiResult = __raw_readl(EP93XX_TOUCHSCREEN_XYRESULT);
+    } while (!(uiResult & TSXYRESULT_SDR));
+
+}
+
+static unsigned int ADCGetData(unsigned int uiSamples, unsigned int uiMaxDiff)
+{
+    unsigned int uiResult, uiValue, uiCount, uiLowest, uiHighest, uiSum, uiAve;
+
+    do
+    {
+	/*
+	 * Initialize our values.
+	 */
+	uiLowest        = 0xfffffff;
+	uiHighest       = 0;
+	uiSum           = 0;
+
+	for (uiCount = 0; uiCount < uiSamples; uiCount++)
+	{
+	    /*
+	     * Read the touch screen four more times and average.
+	     */
+	    do {
+		uiResult = __raw_readl(EP93XX_TOUCHSCREEN_XYRESULT);
+	    } while (!(uiResult & TSXYRESULT_SDR));
+
+	    uiValue = (uiResult & TSXYRESULT_AD_MASK) >> TSXYRESULT_AD_SHIFT;
+	    uiValue = ((uiValue >> 4) + ((1 + TSXYRESULT_X_MASK)>>1)) & TSXYRESULT_X_MASK;
+
+	    /*
+	     * Add up the values.
+	     */
+	    uiSum += uiValue;
+
+	    /*
+	     * Get the lowest and highest values.
+	     */
+	    if (uiValue < uiLowest)
+	    {
+		uiLowest = uiValue;
+	    }
+	    if (uiValue > uiHighest)
+	    {
+		uiHighest = uiValue;
+	    }
+	}
+    } while ((uiHighest - uiLowest) > uiMaxDiff);
+
+    /*
+     * Calculate the Average value.
+     */
+    uiAve = uiSum / uiSamples;
+
+    return uiAve;
+}
+
+/*
+ * CalculateInvPressure
+ *
+ * Is the Touch Valid.  Touch is not valid if the X or Y value is not
+ * in range and the pressure is not  enough.
+ *
+ * Touch resistance can be measured by the following formula:
+ *
+ *          Rx * X *     Z2
+ * Rtouch = --------- * (-- - 1)
+ *           4096        Z1
+ *
+ * This is simplified in the ration of Rtouch to Rx.  The lower the value, the
+ * higher the pressure.
+ *
+ *                     Z2
+ * InvPressure =  X * (-- - 1)
+ *                     Z1
+ */
+static unsigned int CalculateInvPressure(void)
+{
+    unsigned int uiInvPressure;
+
+    /*
+     * Check to see if the point is valid.
+     */
+    if (sTouch.uiZ1 < MIN_Z1_VALUE)
+    {
+	uiInvPressure = 0x10000;
+    }
+
+    /*
+     * Can omit the pressure calculation if you need to get rid of the division.
+     */
+    else
+    {
+	uiInvPressure = ((sTouch.uiX * sTouch.uiZ2) / sTouch.uiZ1) - sTouch.uiX;
+    }
+
+    return uiInvPressure;
+}
+
+/*
+ * TS_Hardware_Scan_Mode
+ *
+ * Enables the ep93xx ts scanning engine so that when the pen goes down
+ * we will get an interrupt.
+ */
+static void TS_Hardware_Scan_Mode(void)
+{
+    unsigned int uiDevCfg;
+
+    /*
+     * Disable the soft scanning engine.
+     */
+    sTouch.state = TS_STATE_STOPPED;
+    Stop_Timer2();
+
+    /*
+     * Clear the TIN (Touchscreen INactive) bit so we can go to
+     * automatic scanning mode.
+     */
+    uiDevCfg = __raw_readl(EP93XX_SYSCON_DEVCFG);
+    ep93xx_syscon_swlocked_write(uiDevCfg & ~EP93XX_SYSCON_DEVCFG_TIN,
+				 EP93XX_SYSCON_DEVCFG);
+
+    /*
+     * Enable the touch screen scanning state machine by setting
+     * the ENABLE bit.
+     */
+    __raw_writel(TSSETUP_DEFAULT | TSSETUP_ENABLE, EP93XX_TOUCHSCREEN_SETUP);
+
+    /*
+     * Set the flag to show that we are in interrupt mode.
+     */
+    gScanningMode = TS_MODE_HARDWARE_SCAN;
+
+    /*
+     * Initialize EP93XX_TOUCHSCREEN_SETUP2 register.
+     */
+    __raw_writel(TSSETUP2_DEFAULT, EP93XX_TOUCHSCREEN_SETUP2);
+
+}
+
+/*
+ * TS_Soft_Scan_Mode
+ *
+ * Sets the touch screen to manual polling mode.
+ */
+static void TS_Soft_Scan_Mode(void)
+{
+    unsigned int uiDevCfg;
+
+    if (gScanningMode != TS_MODE_SOFT_SCAN)
+    {
+	/*
+	 * Disable the touch screen scanning state machine by clearing
+	 * the ENABLE bit.
+	 */
+	__raw_writel(TSSETUP_DEFAULT, EP93XX_TOUCHSCREEN_SETUP);
+
+	/*
+	 * Set the TIN bit so we can do manual touchscreen polling.
+	 */
+	uiDevCfg = __raw_readl(EP93XX_SYSCON_DEVCFG);
+	ep93xx_syscon_swlocked_write(uiDevCfg | EP93XX_SYSCON_DEVCFG_TIN,
+				     EP93XX_SYSCON_DEVCFG);
+    }
+
+    /*
+     * Set the switch register up for the first ADC reading
+     */
+    ep93xx_ts_set_direct(sSwitchSettings.uiSwitchZ1);
+
+    /*
+     * Initialize our software state machine to know which ADC
+     * reading to take
+     */
+    sTouch.state = TS_STATE_Z1;
+
+    /*
+     * Set the timer so after a mSec or two settling delay it will
+     * take the first ADC reading.
+     */
+    Set_Timer2_uSec(EP93XX_TS_PER_POINT_DELAY_USEC);
+
+    /*
+     * Note that we are in sw scanning mode not hw scanning mode.
+     */
+    gScanningMode = TS_MODE_SOFT_SCAN;
+
+}
+
+static void Set_Timer2_uSec(unsigned int uiDelay_uSec)
+{
+    unsigned int uiClockTicks;
+
+    /*
+     * Stop timer 2
+     */
+    __raw_writel(0, EP93XX_TIMER2_CONTROL);
+
+    uiClockTicks = ((uiDelay_uSec * 508) + 999) / 1000;
+    __raw_writel(uiClockTicks, EP93XX_TIMER2_LOAD);
+    __raw_writel(uiClockTicks, EP93XX_TIMER2_VALUE);
+
+    /*
+     * Set up Timer 2 for 508 kHz clock and periodic mode.
+     */
+    __raw_writel(0xC8, EP93XX_TIMER2_CONTROL);
+
+}
+
+static void Stop_Timer2(void)
+{
+    __raw_writel(0, EP93XX_TIMER2_CONTROL);
+}
+
+/*
+ * Initialization and exit routines
+ */
+int __init ep93xx_ts_init(void)
+{
+    int retval;
+
+    retval = request_irq(IRQ_EP93XX_TOUCH, ep93xx_ts_isr,
+			 IRQF_DISABLED, "ep93xx_ts", 0);
+    if (retval)
+    {
+	printk(KERN_WARNING "ep93xx_ts: failed to get touchscreen IRQ\n");
+	return retval;
+    }
+
+    retval = request_irq(IRQ_EP93XX_TIMER2, ep93xx_timer2_isr,
+			 IRQF_DISABLED, "ep93xx_timer2", 0);
+    if (retval)
+    {
+	printk(KERN_WARNING "ep93xx_ts: failed to get timer2 IRQ\n");
+	free_irq(IRQ_EP93XX_TOUCH, 0);
+	return retval;
+    }
+
+    misc_register(&ep93xx_ts_miscdev);
+
+    sTouch.state = TS_STATE_STOPPED;
+    gScanningMode = TS_MODE_UN_INITIALIZED;
+
+    printk(KERN_NOTICE "ep93xx touchscreen driver configured for 4-wire operation\n");
+
+    return 0;
+}
+
+void __exit ep93xx_ts_exit(void)
+{
+    Stop_Timer2();
+
+    free_irq(IRQ_EP93XX_TOUCH, 0);
+    free_irq(IRQ_EP93XX_TIMER2, 0);
+
+    misc_deregister(&ep93xx_ts_miscdev);
+}
+
+module_init(ep93xx_ts_init);
+module_exit(ep93xx_ts_exit);
+
+MODULE_DESCRIPTION("Cirrus EP93xx touchscreen driver");
+MODULE_SUPPORTED_DEVICE("touchscreen/ep93xx");
+MODULE_LICENSE("GPL");
--- a/arch/arm/mach-ep93xx/core.c
+++ b/arch/arm/mach-ep93xx/core.c
@@ -207,6 +207,7 @@ void ep93xx_syscon_swlocked_write(unsign
 
 	spin_unlock_irqrestore(&syscon_swlock, flags);
 }
+EXPORT_SYMBOL(ep93xx_syscon_swlocked_write);
 
 void ep93xx_devcfg_set_clear(unsigned int set_bits, unsigned int clear_bits)
 {