aboutsummaryrefslogblamecommitdiffstats
path: root/drivers/media/video/omap24xxcam.c
blob: f85b2ed8a2d888d661c4df567fc2a4c4638bd5ee (plain) (tree)
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
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288




































                                                                      
                       












































                                                                             
                                            
                               
                                                          




                                           
                                            
                               
                                                          







































































































































































































































































































































































                                                                                

                                                    































































































































































































































































































































































































































































































































































































































































































































































































































































                                                                                














                                                     







































































































                                                                             
                                                                










































                                                                                
                                              
 



                                                          
                              
















































                                                                           
                                                 














































                                                                      
                                                       








































































































                                                                                
                                                     









                                                                         





                                       

                                                    















                                                                    
                                                     








































                                                                          
                                                                    































































































































































                                                                             
/*
 * drivers/media/video/omap24xxcam.c
 *
 * OMAP 2 camera block driver.
 *
 * Copyright (C) 2004 MontaVista Software, Inc.
 * Copyright (C) 2004 Texas Instruments.
 * Copyright (C) 2007-2008 Nokia Corporation.
 *
 * Contact: Sakari Ailus <sakari.ailus@nokia.com>
 *
 * Based on code from Andy Lowe <source@mvista.com>
 *
 * 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.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details.
 *
 * 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., 51 Franklin St, Fifth Floor, Boston, MA
 * 02110-1301 USA
 */

#include <linux/delay.h>
#include <linux/kernel.h>
#include <linux/interrupt.h>
#include <linux/videodev2.h>
#include <linux/pci.h>		/* needed for videobufs */
#include <linux/version.h>
#include <linux/platform_device.h>
#include <linux/clk.h>
#include <linux/io.h>
#include <linux/slab.h>

#include <media/v4l2-common.h>
#include <media/v4l2-ioctl.h>

#include "omap24xxcam.h"

#define OMAP24XXCAM_VERSION KERNEL_VERSION(0, 0, 0)

#define RESET_TIMEOUT_NS 10000

static void omap24xxcam_reset(struct omap24xxcam_device *cam);
static int omap24xxcam_sensor_if_enable(struct omap24xxcam_device *cam);
static void omap24xxcam_device_unregister(struct v4l2_int_device *s);
static int omap24xxcam_remove(struct platform_device *pdev);

/* module parameters */
static int video_nr = -1;	/* video device minor (-1 ==> auto assign) */
/*
 * Maximum amount of memory to use for capture buffers.
 * Default is 4800KB, enough to double-buffer SXGA.
 */
static int capture_mem = 1280 * 960 * 2 * 2;

static struct v4l2_int_device omap24xxcam;

/*
 *
 * Clocks.
 *
 */

static void omap24xxcam_clock_put(struct omap24xxcam_device *cam)
{
	if (cam->ick != NULL && !IS_ERR(cam->ick))
		clk_put(cam->ick);
	if (cam->fck != NULL && !IS_ERR(cam->fck))
		clk_put(cam->fck);

	cam->ick = cam->fck = NULL;
}

static int omap24xxcam_clock_get(struct omap24xxcam_device *cam)
{
	int rval = 0;

	cam->fck = clk_get(cam->dev, "fck");
	if (IS_ERR(cam->fck)) {
		dev_err(cam->dev, "can't get camera fck");
		rval = PTR_ERR(cam->fck);
		omap24xxcam_clock_put(cam);
		return rval;
	}

	cam->ick = clk_get(cam->dev, "ick");
	if (IS_ERR(cam->ick)) {
		dev_err(cam->dev, "can't get camera ick");
		rval = PTR_ERR(cam->ick);
		omap24xxcam_clock_put(cam);
	}

	return rval;
}

static void omap24xxcam_clock_on(struct omap24xxcam_device *cam)
{
	clk_enable(cam->fck);
	clk_enable(cam->ick);
}

static void omap24xxcam_clock_off(struct omap24xxcam_device *cam)
{
	clk_disable(cam->fck);
	clk_disable(cam->ick);
}

/*
 *
 * Camera core
 *
 */

/*
 * Set xclk.
 *
 * To disable xclk, use value zero.
 */
static void omap24xxcam_core_xclk_set(const struct omap24xxcam_device *cam,
				      u32 xclk)
{
	if (xclk) {
		u32 divisor = CAM_MCLK / xclk;

		if (divisor == 1)
			omap24xxcam_reg_out(cam->mmio_base + CC_REG_OFFSET,
					    CC_CTRL_XCLK,
					    CC_CTRL_XCLK_DIV_BYPASS);
		else
			omap24xxcam_reg_out(cam->mmio_base + CC_REG_OFFSET,
					    CC_CTRL_XCLK, divisor);
	} else
		omap24xxcam_reg_out(cam->mmio_base + CC_REG_OFFSET,
				    CC_CTRL_XCLK, CC_CTRL_XCLK_DIV_STABLE_LOW);
}

static void omap24xxcam_core_hwinit(const struct omap24xxcam_device *cam)
{
	/*
	 * Setting the camera core AUTOIDLE bit causes problems with frame
	 * synchronization, so we will clear the AUTOIDLE bit instead.
	 */
	omap24xxcam_reg_out(cam->mmio_base + CC_REG_OFFSET, CC_SYSCONFIG,
			    CC_SYSCONFIG_AUTOIDLE);

	/* program the camera interface DMA packet size */
	omap24xxcam_reg_out(cam->mmio_base + CC_REG_OFFSET, CC_CTRL_DMA,
			    CC_CTRL_DMA_EN | (DMA_THRESHOLD / 4 - 1));

	/* enable camera core error interrupts */
	omap24xxcam_reg_out(cam->mmio_base + CC_REG_OFFSET, CC_IRQENABLE,
			    CC_IRQENABLE_FW_ERR_IRQ
			    | CC_IRQENABLE_FSC_ERR_IRQ
			    | CC_IRQENABLE_SSC_ERR_IRQ
			    | CC_IRQENABLE_FIFO_OF_IRQ);
}

/*
 * Enable the camera core.
 *
 * Data transfer to the camera DMA starts from next starting frame.
 */
static void omap24xxcam_core_enable(const struct omap24xxcam_device *cam)
{

	omap24xxcam_reg_out(cam->mmio_base + CC_REG_OFFSET, CC_CTRL,
			    cam->cc_ctrl);
}

/*
 * Disable camera core.
 *
 * The data transfer will be stopped immediately (CC_CTRL_CC_RST). The
 * core internal state machines will be reset. Use
 * CC_CTRL_CC_FRAME_TRIG instead if you want to transfer the current
 * frame completely.
 */
static void omap24xxcam_core_disable(const struct omap24xxcam_device *cam)
{
	omap24xxcam_reg_out(cam->mmio_base + CC_REG_OFFSET, CC_CTRL,
			    CC_CTRL_CC_RST);
}

/* Interrupt service routine for camera core interrupts. */
static void omap24xxcam_core_isr(struct omap24xxcam_device *cam)
{
	u32 cc_irqstatus;
	const u32 cc_irqstatus_err =
		CC_IRQSTATUS_FW_ERR_IRQ
		| CC_IRQSTATUS_FSC_ERR_IRQ
		| CC_IRQSTATUS_SSC_ERR_IRQ
		| CC_IRQSTATUS_FIFO_UF_IRQ
		| CC_IRQSTATUS_FIFO_OF_IRQ;

	cc_irqstatus = omap24xxcam_reg_in(cam->mmio_base + CC_REG_OFFSET,
					  CC_IRQSTATUS);
	omap24xxcam_reg_out(cam->mmio_base + CC_REG_OFFSET, CC_IRQSTATUS,
			    cc_irqstatus);

	if (cc_irqstatus & cc_irqstatus_err
	    && !atomic_read(&cam->in_reset)) {
		dev_dbg(cam->dev, "resetting camera, cc_irqstatus 0x%x\n",
			cc_irqstatus);
		omap24xxcam_reset(cam);
	}
}

/*
 *
 * videobuf_buffer handling.
 *
 * Memory for mmapped videobuf_buffers is not allocated
 * conventionally, but by several kmalloc allocations and then
 * creating the scatterlist on our own. User-space buffers are handled
 * normally.
 *
 */

/*
 * Free the memory-mapped buffer memory allocated for a
 * videobuf_buffer and the associated scatterlist.
 */
static void omap24xxcam_vbq_free_mmap_buffer(struct videobuf_buffer *vb)
{
	struct videobuf_dmabuf *dma = videobuf_to_dma(vb);
	size_t alloc_size;
	struct page *page;
	int i;

	if (dma->sglist == NULL)
		return;

	i = dma->sglen;
	while (i) {
		i--;
		alloc_size = sg_dma_len(&dma->sglist[i]);
		page = sg_page(&dma->sglist[i]);
		do {
			ClearPageReserved(page++);
		} while (alloc_size -= PAGE_SIZE);
		__free_pages(sg_page(&dma->sglist[i]),
			     get_order(sg_dma_len(&dma->sglist[i])));
	}

	kfree(dma->sglist);
	dma->sglist = NULL;
}

/* Release all memory related to the videobuf_queue. */
static void omap24xxcam_vbq_free_mmap_buffers(struct videobuf_queue *vbq)
{
	int i;

	mutex_lock(&vbq->vb_lock);

	for (i = 0; i < VIDEO_MAX_FRAME; i++) {
		if (NULL == vbq->bufs[i])
			continue;
		if (V4L2_MEMORY_MMAP != vbq->bufs[i]->memory)
			continue;
		vbq->ops->buf_release(vbq, vbq->bufs[i]);
		omap24xxcam_vbq_free_mmap_buffer(vbq->bufs[i]);
		kfree(vbq->bufs[i]);
		vbq->bufs[i] = NULL;
	}

	mutex_unlock(&vbq->vb_lock);

	videobuf_mmap_free(vbq);
}

/*
 * Allocate physically as contiguous as possible buffer for video
 * frame and allocate and build DMA scatter-gather list for it.
 */
static int omap24xxcam_vbq_alloc_mmap_buffer(struct videobuf_buffer *vb)
{
	unsigned int order;
	size_t alloc_size, size = vb->bsize; /* vb->bsize is page aligned */
	struct page *page;
	int max_pages, err = 0, i = 0;
	struct videobuf_dmabuf *dma = videobuf_to_dma(vb);

	/*
	 * allocate maximum size scatter-gather list. Note this is
	 * overhead. We may not use as many entries as we allocate
	 */
	max_pages = vb->bsize >> PAGE_SHIFT;
	dma->sglist = kcalloc(max_pages, sizeof(*dma->sglist), GFP_KERNEL);
	if (dma->sglist == NULL) {
		err = -ENOMEM;
		goto out;
	}

	while (size) {
		order = get_order(size);
		/*
		 * do not over-allocate even if we would get larger
		 * contiguous chunk that way
		 */
		if ((PAGE_SIZE << order) > size)
			order--;

		/* try to allocate as many contiguous pages as possible */
		page = alloc_pages(GFP_KERNEL | GFP_DMA, order);
		/* if allocation fails, try to allocate smaller amount */
		while (page == NULL) {
			order--;
			page = alloc_pages(GFP_KERNEL | GFP_DMA, order);
			if (page == NULL && !order) {
				err = -ENOMEM;
				goto out;
			}
		}
		size -= (PAGE_SIZE << order);

		/* append allocated chunk of pages into scatter-gather list */
		sg_set_page(&dma->sglist[i], page, PAGE_SIZE << order, 0);
		dma->sglen++;
		i++;

		alloc_size = (PAGE_SIZE << order);

		/* clear pages before giving them to user space */
		memset(page_address(page), 0, alloc_size);

		/* mark allocated pages reserved */
		do {
			SetPageReserved(page++);
		} while (alloc_size -= PAGE_SIZE);
	}
	/*
	 * REVISIT: not fully correct to assign nr_pages == sglen but
	 * video-buf is passing nr_pages for e.g. unmap_sg calls
	 */
	dma->nr_pages = dma->sglen;
	dma->direction = PCI_DMA_FROMDEVICE;

	return 0;

out:
	omap24xxcam_vbq_free_mmap_buffer(vb);
	return err;
}

static int omap24xxcam_vbq_alloc_mmap_buffers(struct videobuf_queue *vbq,
					      unsigned int count)
{
	int i, err = 0;
	struct omap24xxcam_fh *fh =
		container_of(vbq, struct omap24xxcam_fh, vbq);

	mutex_lock(&vbq->vb_lock);

	for (i = 0; i < count; i++) {
		err = omap24xxcam_vbq_alloc_mmap_buffer(vbq->bufs[i]);
		if (err)
			goto out;
		dev_dbg(fh->cam->dev, "sglen is %d for buffer %d\n",
			videobuf_to_dma(vbq->bufs[i])->sglen, i);
	}

	mutex_unlock(&vbq->vb_lock);

	return 0;
out:
	while (i) {
		i--;
		omap24xxcam_vbq_free_mmap_buffer(vbq->bufs[i]);
	}

	mutex_unlock(&vbq->vb_lock);

	return err;
}

/*
 * This routine is called from interrupt context when a scatter-gather DMA
 * transfer of a videobuf_buffer completes.
 */
static void omap24xxcam_vbq_complete(struct omap24xxcam_sgdma *sgdma,
				     u32 csr, void *arg)
{
	struct omap24xxcam_device *cam =
		container_of(sgdma, struct omap24xxcam_device, sgdma);
	struct omap24xxcam_fh *fh = cam->streaming->private_data;
	struct videobuf_buffer *vb = (struct videobuf_buffer *)arg;
	const u32 csr_error = CAMDMA_CSR_MISALIGNED_ERR
		| CAMDMA_CSR_SUPERVISOR_ERR | CAMDMA_CSR_SECURE_ERR
		| CAMDMA_CSR_TRANS_ERR | CAMDMA_CSR_DROP;
	unsigned long flags;

	spin_lock_irqsave(&cam->core_enable_disable_lock, flags);
	if (--cam->sgdma_in_queue == 0)
		omap24xxcam_core_disable(cam);
	spin_unlock_irqrestore(&cam->core_enable_disable_lock, flags);

	do_gettimeofday(&vb->ts);
	vb->field_count = atomic_add_return(2, &fh->field_count);
	if (csr & csr_error) {
		vb->state = VIDEOBUF_ERROR;
		if (!atomic_read(&fh->cam->in_reset)) {
			dev_dbg(cam->dev, "resetting camera, csr 0x%x\n", csr);
			omap24xxcam_reset(cam);
		}
	} else
		vb->state = VIDEOBUF_DONE;
	wake_up(&vb->done);
}

static void omap24xxcam_vbq_release(struct videobuf_queue *vbq,
				    struct videobuf_buffer *vb)
{
	struct videobuf_dmabuf *dma = videobuf_to_dma(vb);

	/* wait for buffer, especially to get out of the sgdma queue */
	videobuf_waiton(vb, 0, 0);
	if (vb->memory == V4L2_MEMORY_MMAP) {
		dma_unmap_sg(vbq->dev, dma->sglist, dma->sglen,
			     dma->direction);
		dma->direction = DMA_NONE;
	} else {
		videobuf_dma_unmap(vbq, videobuf_to_dma(vb));
		videobuf_dma_free(videobuf_to_dma(vb));
	}

	vb->state = VIDEOBUF_NEEDS_INIT;
}

/*
 * Limit the number of available kernel image capture buffers based on the
 * number requested, the currently selected image size, and the maximum
 * amount of memory permitted for kernel capture buffers.
 */
static int omap24xxcam_vbq_setup(struct videobuf_queue *vbq, unsigned int *cnt,
				 unsigned int *size)
{
	struct omap24xxcam_fh *fh = vbq->priv_data;

	if (*cnt <= 0)
		*cnt = VIDEO_MAX_FRAME;	/* supply a default number of buffers */

	if (*cnt > VIDEO_MAX_FRAME)
		*cnt = VIDEO_MAX_FRAME;

	*size = fh->pix.sizeimage;

	/* accessing fh->cam->capture_mem is ok, it's constant */
	if (*size * *cnt > fh->cam->capture_mem)
		*cnt = fh->cam->capture_mem / *size;

	return 0;
}

static int omap24xxcam_dma_iolock(struct videobuf_queue *vbq,
				  struct videobuf_dmabuf *dma)
{
	int err = 0;

	dma->direction = PCI_DMA_FROMDEVICE;
	if (!dma_map_sg(vbq->dev, dma->sglist, dma->sglen, dma->direction)) {
		kfree(dma->sglist);
		dma->sglist = NULL;
		dma->sglen = 0;
		err = -EIO;
	}

	return err;
}

static int omap24xxcam_vbq_prepare(struct videobuf_queue *vbq,
				   struct videobuf_buffer *vb,
				   enum v4l2_field field)
{
	struct omap24xxcam_fh *fh = vbq->priv_data;
	int err = 0;

	/*
	 * Accessing pix here is okay since it's constant while
	 * streaming is on (and we only get called then).
	 */
	if (vb->baddr) {
		/* This is a userspace buffer. */
		if (fh->pix.sizeimage > vb->bsize) {
			/* The buffer isn't big enough. */
			err = -EINVAL;
		} else
			vb->size = fh->pix.sizeimage;
	} else {
		if (vb->state != VIDEOBUF_NEEDS_INIT) {
			/*
			 * We have a kernel bounce buffer that has
			 * already been allocated.
			 */
			if (fh->pix.sizeimage > vb->size) {
				/*
				 * The image size has been changed to
				 * a larger size since this buffer was
				 * allocated, so we need to free and
				 * reallocate it.
				 */
				omap24xxcam_vbq_release(vbq, vb);
				vb->size = fh->pix.sizeimage;
			}
		} else {
			/* We need to allocate a new kernel bounce buffer. */
			vb->size = fh->pix.sizeimage;
		}
	}

	if (err)
		return err;

	vb->width = fh->pix.width;
	vb->height = fh->pix.height;
	vb->field = field;

	if (vb->state == VIDEOBUF_NEEDS_INIT) {
		if (vb->memory == V4L2_MEMORY_MMAP)
			/*
			 * we have built the scatter-gather list by ourself so
			 * do the scatter-gather mapping as well
			 */
			err = omap24xxcam_dma_iolock(vbq, videobuf_to_dma(vb));
		else
			err = videobuf_iolock(vbq, vb, NULL);
	}

	if (!err)
		vb->state = VIDEOBUF_PREPARED;
	else
		omap24xxcam_vbq_release(vbq, vb);

	return err;
}

static void omap24xxcam_vbq_queue(struct videobuf_queue *vbq,
				  struct videobuf_buffer *vb)
{
	struct omap24xxcam_fh *fh = vbq->priv_data;
	struct omap24xxcam_device *cam = fh->cam;
	enum videobuf_state state = vb->state;
	unsigned long flags;
	int err;

	/*
	 * FIXME: We're marking the buffer active since we have no
	 * pretty way of marking it active exactly when the
	 * scatter-gather transfer starts.
	 */
	vb->state = VIDEOBUF_ACTIVE;

	err = omap24xxcam_sgdma_queue(&fh->cam->sgdma,
				      videobuf_to_dma(vb)->sglist,
				      videobuf_to_dma(vb)->sglen, vb->size,
				      omap24xxcam_vbq_complete, vb);

	if (!err) {
		spin_lock_irqsave(&cam->core_enable_disable_lock, flags);
		if (++cam->sgdma_in_queue == 1
		    && !atomic_read(&cam->in_reset))
			omap24xxcam_core_enable(cam);
		spin_unlock_irqrestore(&cam->core_enable_disable_lock, flags);
	} else {
		/*
		 * Oops. We're not supposed to get any errors here.
		 * The only way we could get an error is if we ran out
		 * of scatter-gather DMA slots, but we are supposed to
		 * have at least as many scatter-gather DMA slots as
		 * video buffers so that can't happen.
		 */
		dev_err(cam->dev, "failed to queue a video buffer for dma!\n");
		dev_err(cam->dev, "likely a bug in the driver!\n");
		vb->state = state;
	}
}

static struct videobuf_queue_ops omap24xxcam_vbq_ops = {
	.buf_setup   = omap24xxcam_vbq_setup,
	.buf_prepare = omap24xxcam_vbq_prepare,
	.buf_queue   = omap24xxcam_vbq_queue,
	.buf_release = omap24xxcam_vbq_release,
};

/*
 *
 * OMAP main camera system
 *
 */

/*
 * Reset camera block to power-on state.
 */
static void omap24xxcam_poweron_reset(struct omap24xxcam_device *cam)
{
	int max_loop = RESET_TIMEOUT_NS;

	/* Reset whole camera subsystem */
	omap24xxcam_reg_out(cam->mmio_base,
			    CAM_SYSCONFIG,
			    CAM_SYSCONFIG_SOFTRESET);

	/* Wait till it's finished */
	while (!(omap24xxcam_reg_in(cam->mmio_base, CAM_SYSSTATUS)
		 & CAM_SYSSTATUS_RESETDONE)
	       && --max_loop) {
		ndelay(1);
	}

	if (!(omap24xxcam_reg_in(cam->mmio_base, CAM_SYSSTATUS)
	      & CAM_SYSSTATUS_RESETDONE))
		dev_err(cam->dev, "camera soft reset timeout\n");
}

/*
 * (Re)initialise the camera block.
 */
static void omap24xxcam_hwinit(struct omap24xxcam_device *cam)
{
	omap24xxcam_poweron_reset(cam);

	/* set the camera subsystem autoidle bit */
	omap24xxcam_reg_out(cam->mmio_base, CAM_SYSCONFIG,
			    CAM_SYSCONFIG_AUTOIDLE);

	/* set the camera MMU autoidle bit */
	omap24xxcam_reg_out(cam->mmio_base,
			    CAMMMU_REG_OFFSET + CAMMMU_SYSCONFIG,
			    CAMMMU_SYSCONFIG_AUTOIDLE);

	omap24xxcam_core_hwinit(cam);

	omap24xxcam_dma_hwinit(&cam->sgdma.dma);
}

/*
 * Callback for dma transfer stalling.
 */
static void omap24xxcam_stalled_dma_reset(unsigned long data)
{
	struct omap24xxcam_device *cam = (struct omap24xxcam_device *)data;

	if (!atomic_read(&cam->in_reset)) {
		dev_dbg(cam->dev, "dma stalled, resetting camera\n");
		omap24xxcam_reset(cam);
	}
}

/*
 * Stop capture. Mark we're doing a reset, stop DMA transfers and
 * core. (No new scatter-gather transfers will be queued whilst
 * in_reset is non-zero.)
 *
 * If omap24xxcam_capture_stop is called from several places at
 * once, only the first call will have an effect. Similarly, the last
 * call omap24xxcam_streaming_cont will have effect.
 *
 * Serialisation is ensured by using cam->core_enable_disable_lock.
 */
static void omap24xxcam_capture_stop(struct omap24xxcam_device *cam)
{
	unsigned long flags;

	spin_lock_irqsave(&cam->core_enable_disable_lock, flags);

	if (atomic_inc_return(&cam->in_reset) != 1) {
		spin_unlock_irqrestore(&cam->core_enable_disable_lock, flags);
		return;
	}

	omap24xxcam_core_disable(cam);

	spin_unlock_irqrestore(&cam->core_enable_disable_lock, flags);

	omap24xxcam_sgdma_sync(&cam->sgdma);
}

/*
 * Reset and continue streaming.
 *
 * Note: Resetting the camera FIFO via the CC_RST bit in the CC_CTRL
 * register is supposed to be sufficient to recover from a camera
 * interface error, but it doesn't seem to be enough. If we only do
 * that then subsequent image captures are out of sync by either one
 * or two times DMA_THRESHOLD bytes. Resetting and re-initializing the
 * entire camera subsystem prevents the problem with frame
 * synchronization.
 */
static void omap24xxcam_capture_cont(struct omap24xxcam_device *cam)
{
	unsigned long flags;

	spin_lock_irqsave(&cam->core_enable_disable_lock, flags);

	if (atomic_read(&cam->in_reset) != 1)
		goto out;

	omap24xxcam_hwinit(cam);

	omap24xxcam_sensor_if_enable(cam);

	omap24xxcam_sgdma_process(&cam->sgdma);

	if (cam->sgdma_in_queue)
		omap24xxcam_core_enable(cam);

out:
	atomic_dec(&cam->in_reset);
	spin_unlock_irqrestore(&cam->core_enable_disable_lock, flags);
}

static ssize_t
omap24xxcam_streaming_show(struct device *dev, struct device_attribute *attr,
		char *buf)
{
	struct omap24xxcam_device *cam = dev_get_drvdata(dev);

	return sprintf(buf, "%s\n", cam->streaming ?  "active" : "inactive");
}
static DEVICE_ATTR(streaming, S_IRUGO, omap24xxcam_streaming_show, NULL);

/*
 * Stop capture and restart it. I.e. reset the camera during use.
 */
static void omap24xxcam_reset(struct omap24xxcam_device *cam)
{
	omap24xxcam_capture_stop(cam);
	omap24xxcam_capture_cont(cam);
}

/*
 * The main interrupt handler.
 */
static irqreturn_t omap24xxcam_isr(int irq, void *arg)
{
	struct omap24xxcam_device *cam = (struct omap24xxcam_device *)arg;
	u32 irqstatus;
	unsigned int irqhandled = 0;

	irqstatus = omap24xxcam_reg_in(cam->mmio_base, CAM_IRQSTATUS);

	if (irqstatus &
	    (CAM_IRQSTATUS_DMA_IRQ2 | CAM_IRQSTATUS_DMA_IRQ1
	     | CAM_IRQSTATUS_DMA_IRQ0)) {
		omap24xxcam_dma_isr(&cam->sgdma.dma);
		irqhandled = 1;
	}
	if (irqstatus & CAM_IRQSTATUS_CC_IRQ) {
		omap24xxcam_core_isr(cam);
		irqhandled = 1;
	}
	if (irqstatus & CAM_IRQSTATUS_MMU_IRQ)
		dev_err(cam->dev, "unhandled camera MMU interrupt!\n");

	return IRQ_RETVAL(irqhandled);
}

/*
 *
 * Sensor handling.
 *
 */

/*
 * Enable the external sensor interface. Try to negotiate interface
 * parameters with the sensor and start using the new ones. The calls
 * to sensor_if_enable and sensor_if_disable need not to be balanced.
 */
static int omap24xxcam_sensor_if_enable(struct omap24xxcam_device *cam)
{
	int rval;
	struct v4l2_ifparm p;

	rval = vidioc_int_g_ifparm(cam->sdev, &p);
	if (rval) {
		dev_err(cam->dev, "vidioc_int_g_ifparm failed with %d\n", rval);
		return rval;
	}

	cam->if_type = p.if_type;

	cam->cc_ctrl = CC_CTRL_CC_EN;

	switch (p.if_type) {
	case V4L2_IF_TYPE_BT656:
		if (p.u.bt656.frame_start_on_rising_vs)
			cam->cc_ctrl |= CC_CTRL_NOBT_SYNCHRO;
		if (p.u.bt656.bt_sync_correct)
			cam->cc_ctrl |= CC_CTRL_BT_CORRECT;
		if (p.u.bt656.swap)
			cam->cc_ctrl |= CC_CTRL_PAR_ORDERCAM;
		if (p.u.bt656.latch_clk_inv)
			cam->cc_ctrl |= CC_CTRL_PAR_CLK_POL;
		if (p.u.bt656.nobt_hs_inv)
			cam->cc_ctrl |= CC_CTRL_NOBT_HS_POL;
		if (p.u.bt656.nobt_vs_inv)
			cam->cc_ctrl |= CC_CTRL_NOBT_VS_POL;

		switch (p.u.bt656.mode) {
		case V4L2_IF_TYPE_BT656_MODE_NOBT_8BIT:
			cam->cc_ctrl |= CC_CTRL_PAR_MODE_NOBT8;
			break;
		case V4L2_IF_TYPE_BT656_MODE_NOBT_10BIT:
			cam->cc_ctrl |= CC_CTRL_PAR_MODE_NOBT10;
			break;
		case V4L2_IF_TYPE_BT656_MODE_NOBT_12BIT:
			cam->cc_ctrl |= CC_CTRL_PAR_MODE_NOBT12;
			break;
		case V4L2_IF_TYPE_BT656_MODE_BT_8BIT:
			cam->cc_ctrl |= CC_CTRL_PAR_MODE_BT8;
			break;
		case V4L2_IF_TYPE_BT656_MODE_BT_10BIT:
			cam->cc_ctrl |= CC_CTRL_PAR_MODE_BT10;
			break;
		default:
			dev_err(cam->dev,
				"bt656 interface mode %d not supported\n",
				p.u.bt656.mode);
			return -EINVAL;
		}
		/*
		 * The clock rate that the sensor wants has changed.
		 * We have to adjust the xclk from OMAP 2 side to
		 * match the sensor's wish as closely as possible.
		 */
		if (p.u.bt656.clock_curr != cam->if_u.bt656.xclk) {
			u32 xclk = p.u.bt656.clock_curr;
			u32 divisor;

			if (xclk == 0)
				return -EINVAL;

			if (xclk > CAM_MCLK)
				xclk = CAM_MCLK;

			divisor = CAM_MCLK / xclk;
			if (divisor * xclk < CAM_MCLK)
				divisor++;
			if (CAM_MCLK / divisor < p.u.bt656.clock_min
			    && divisor > 1)
				divisor--;
			if (divisor > 30)
				divisor = 30;

			xclk = CAM_MCLK / divisor;

			if (xclk < p.u.bt656.clock_min
			    || xclk > p.u.bt656.clock_max)
				return -EINVAL;

			cam->if_u.bt656.xclk = xclk;
		}
		omap24xxcam_core_xclk_set(cam, cam->if_u.bt656.xclk);
		break;
	default:
		/* FIXME: how about other interfaces? */
		dev_err(cam->dev, "interface type %d not supported\n",
			p.if_type);
		return -EINVAL;
	}

	return 0;
}

static void omap24xxcam_sensor_if_disable(const struct omap24xxcam_device *cam)
{
	switch (cam->if_type) {
	case V4L2_IF_TYPE_BT656:
		omap24xxcam_core_xclk_set(cam, 0);
		break;
	}
}

/*
 * Initialise the sensor hardware.
 */
static int omap24xxcam_sensor_init(struct omap24xxcam_device *cam)
{
	int err = 0;
	struct v4l2_int_device *sdev = cam->sdev;

	omap24xxcam_clock_on(cam);
	err = omap24xxcam_sensor_if_enable(cam);
	if (err) {
		dev_err(cam->dev, "sensor interface could not be enabled at "
			"initialisation, %d\n", err);
		cam->sdev = NULL;
		goto out;
	}

	/* power up sensor during sensor initialization */
	vidioc_int_s_power(sdev, 1);

	err = vidioc_int_dev_init(sdev);
	if (err) {
		dev_err(cam->dev, "cannot initialize sensor, error %d\n", err);
		/* Sensor init failed --- it's nonexistent to us! */
		cam->sdev = NULL;
		goto out;
	}

	dev_info(cam->dev, "sensor is %s\n", sdev->name);

out:
	omap24xxcam_sensor_if_disable(cam);
	omap24xxcam_clock_off(cam);

	vidioc_int_s_power(sdev, 0);

	return err;
}

static void omap24xxcam_sensor_exit(struct omap24xxcam_device *cam)
{
	if (cam->sdev)
		vidioc_int_dev_exit(cam->sdev);
}

static void omap24xxcam_sensor_disable(struct omap24xxcam_device *cam)
{
	omap24xxcam_sensor_if_disable(cam);
	omap24xxcam_clock_off(cam);
	vidioc_int_s_power(cam->sdev, 0);
}

/*
 * Power-up and configure camera sensor. It's ready for capturing now.
 */
static int omap24xxcam_sensor_enable(struct omap24xxcam_device *cam)
{
	int rval;

	omap24xxcam_clock_on(cam);

	omap24xxcam_sensor_if_enable(cam);

	rval = vidioc_int_s_power(cam->sdev, 1);
	if (rval)
		goto out;

	rval = vidioc_int_init(cam->sdev);
	if (rval)
		goto out;

	return 0;

out:
	omap24xxcam_sensor_disable(cam);

	return rval;
}

static void omap24xxcam_sensor_reset_work(struct work_struct *work)
{
	struct omap24xxcam_device *cam =
		container_of(work, struct omap24xxcam_device,
			     sensor_reset_work);

	if (atomic_read(&cam->reset_disable))
		return;

	omap24xxcam_capture_stop(cam);

	if (vidioc_int_reset(cam->sdev) == 0) {
		vidioc_int_init(cam->sdev);
	} else {
		/* Can't reset it by vidioc_int_reset. */
		omap24xxcam_sensor_disable(cam);
		omap24xxcam_sensor_enable(cam);
	}

	omap24xxcam_capture_cont(cam);
}

/*
 *
 * IOCTL interface.
 *
 */

static int vidioc_querycap(struct file *file, void *fh,
			   struct v4l2_capability *cap)
{
	struct omap24xxcam_fh *ofh = fh;
	struct omap24xxcam_device *cam = ofh->cam;

	strlcpy(cap->driver, CAM_NAME, sizeof(cap->driver));
	strlcpy(cap->card, cam->vfd->name, sizeof(cap->card));
	cap->version = OMAP24XXCAM_VERSION;
	cap->capabilities = V4L2_CAP_VIDEO_CAPTURE | V4L2_CAP_STREAMING;

	return 0;
}

static int vidioc_enum_fmt_vid_cap(struct file *file, void *fh,
				   struct v4l2_fmtdesc *f)
{
	struct omap24xxcam_fh *ofh = fh;
	struct omap24xxcam_device *cam = ofh->cam;
	int rval;

	rval = vidioc_int_enum_fmt_cap(cam->sdev, f);

	return rval;
}

static int vidioc_g_fmt_vid_cap(struct file *file, void *fh,
				struct v4l2_format *f)
{
	struct omap24xxcam_fh *ofh = fh;
	struct omap24xxcam_device *cam = ofh->cam;
	int rval;

	mutex_lock(&cam->mutex);
	rval = vidioc_int_g_fmt_cap(cam->sdev, f);
	mutex_unlock(&cam->mutex);

	return rval;
}

static int vidioc_s_fmt_vid_cap(struct file *file, void *fh,
				struct v4l2_format *f)
{
	struct omap24xxcam_fh *ofh = fh;
	struct omap24xxcam_device *cam = ofh->cam;
	int rval;

	mutex_lock(&cam->mutex);
	if (cam->streaming) {
		rval = -EBUSY;
		goto out;
	}

	rval = vidioc_int_s_fmt_cap(cam->sdev, f);

out:
	mutex_unlock(&cam->mutex);

	if (!rval) {
		mutex_lock(&ofh->vbq.vb_lock);
		ofh->pix = f->fmt.pix;
		mutex_unlock(&ofh->vbq.vb_lock);
	}

	memset(f, 0, sizeof(*f));
	vidioc_g_fmt_vid_cap(file, fh, f);

	return rval;
}

static int vidioc_try_fmt_vid_cap(struct file *file, void *fh,
				  struct v4l2_format *f)
{
	struct omap24xxcam_fh *ofh = fh;
	struct omap24xxcam_device *cam = ofh->cam;
	int rval;

	mutex_lock(&cam->mutex);
	rval = vidioc_int_try_fmt_cap(cam->sdev, f);
	mutex_unlock(&cam->mutex);

	return rval;
}

static int vidioc_reqbufs(struct file *file, void *fh,
			  struct v4l2_requestbuffers *b)
{
	struct omap24xxcam_fh *ofh = fh;
	struct omap24xxcam_device *cam = ofh->cam;
	int rval;

	mutex_lock(&cam->mutex);
	if (cam->streaming) {
		mutex_unlock(&cam->mutex);
		return -EBUSY;
	}

	omap24xxcam_vbq_free_mmap_buffers(&ofh->vbq);
	mutex_unlock(&cam->mutex);

	rval = videobuf_reqbufs(&ofh->vbq, b);

	/*
	 * Either videobuf_reqbufs failed or the buffers are not
	 * memory-mapped (which would need special attention).
	 */
	if (rval < 0 || b->memory != V4L2_MEMORY_MMAP)
		goto out;

	rval = omap24xxcam_vbq_alloc_mmap_buffers(&ofh->vbq, rval);
	if (rval)
		omap24xxcam_vbq_free_mmap_buffers(&ofh->vbq);

out:
	return rval;
}

static int vidioc_querybuf(struct file *file, void *fh,
			   struct v4l2_buffer *b)
{
	struct omap24xxcam_fh *ofh = fh;

	return videobuf_querybuf(&ofh->vbq, b);
}

static int vidioc_qbuf(struct file *file, void *fh, struct v4l2_buffer *b)
{
	struct omap24xxcam_fh *ofh = fh;

	return videobuf_qbuf(&ofh->vbq, b);
}

static int vidioc_dqbuf(struct file *file, void *fh, struct v4l2_buffer *b)
{
	struct omap24xxcam_fh *ofh = fh;
	struct omap24xxcam_device *cam = ofh->cam;
	struct videobuf_buffer *vb;
	int rval;

videobuf_dqbuf_again:
	rval = videobuf_dqbuf(&ofh->vbq, b, file->f_flags & O_NONBLOCK);
	if (rval)
		goto out;

	vb = ofh->vbq.bufs[b->index];

	mutex_lock(&cam->mutex);
	/* _needs_reset returns -EIO if reset is required. */
	rval = vidioc_int_g_needs_reset(cam->sdev, (void *)vb->baddr);
	mutex_unlock(&cam->mutex);
	if (rval == -EIO)
		schedule_work(&cam->sensor_reset_work);
	else
		rval = 0;

out:
	/*
	 * This is a hack. We don't want to show -EIO to the user
	 * space. Requeue the buffer and try again if we're not doing
	 * this in non-blocking mode.
	 */
	if (rval == -EIO) {
		videobuf_qbuf(&ofh->vbq, b);
		if (!(file->f_flags & O_NONBLOCK))
			goto videobuf_dqbuf_again;
		/*
		 * We don't have a videobuf_buffer now --- maybe next
		 * time...
		 */
		rval = -EAGAIN;
	}

	return rval;
}

static int vidioc_streamon(struct file *file, void *fh, enum v4l2_buf_type i)
{
	struct omap24xxcam_fh *ofh = fh;
	struct omap24xxcam_device *cam = ofh->cam;
	int rval;

	mutex_lock(&cam->mutex);
	if (cam->streaming) {
		rval = -EBUSY;
		goto out;
	}

	rval = omap24xxcam_sensor_if_enable(cam);
	if (rval) {
		dev_dbg(cam->dev, "vidioc_int_g_ifparm failed\n");
		goto out;
	}

	rval = videobuf_streamon(&ofh->vbq);
	if (!rval) {
		cam->streaming = file;
		sysfs_notify(&cam->dev->kobj, NULL, "streaming");
	}

out:
	mutex_unlock(&cam->mutex);

	return rval;
}

static int vidioc_streamoff(struct file *file, void *fh, enum v4l2_buf_type i)
{
	struct omap24xxcam_fh *ofh = fh;
	struct omap24xxcam_device *cam = ofh->cam;
	struct videobuf_queue *q = &ofh->vbq;
	int rval;

	atomic_inc(&cam->reset_disable);

	flush_scheduled_work();

	rval = videobuf_streamoff(q);
	if (!rval) {
		mutex_lock(&cam->mutex);
		cam->streaming = NULL;
		mutex_unlock(&cam->mutex);
		sysfs_notify(&cam->dev->kobj, NULL, "streaming");
	}

	atomic_dec(&cam->reset_disable);

	return rval;
}

static int vidioc_enum_input(struct file *file, void *fh,
			     struct v4l2_input *inp)
{
	if (inp->index > 0)
		return -EINVAL;

	strlcpy(inp->name, "camera", sizeof(inp->name));
	inp->type = V4L2_INPUT_TYPE_CAMERA;

	return 0;
}

static int vidioc_g_input(struct file *file, void *fh, unsigned int *i)
{
	*i = 0;

	return 0;
}

static int vidioc_s_input(struct file *file, void *fh, unsigned int i)
{
	if (i > 0)
		return -EINVAL;

	return 0;
}

static int vidioc_queryctrl(struct file *file, void *fh,
			    struct v4l2_queryctrl *a)
{
	struct omap24xxcam_fh *ofh = fh;
	struct omap24xxcam_device *cam = ofh->cam;
	int rval;

	rval = vidioc_int_queryctrl(cam->sdev, a);

	return rval;
}

static int vidioc_g_ctrl(struct file *file, void *fh,
			 struct v4l2_control *a)
{
	struct omap24xxcam_fh *ofh = fh;
	struct omap24xxcam_device *cam = ofh->cam;
	int rval;

	mutex_lock(&cam->mutex);
	rval = vidioc_int_g_ctrl(cam->sdev, a);
	mutex_unlock(&cam->mutex);

	return rval;
}

static int vidioc_s_ctrl(struct file *file, void *fh,
			 struct v4l2_control *a)
{
	struct omap24xxcam_fh *ofh = fh;
	struct omap24xxcam_device *cam = ofh->cam;
	int rval;

	mutex_lock(&cam->mutex);
	rval = vidioc_int_s_ctrl(cam->sdev, a);
	mutex_unlock(&cam->mutex);

	return rval;
}

static int vidioc_g_parm(struct file *file, void *fh,
			 struct v4l2_streamparm *a) {
	struct omap24xxcam_fh *ofh = fh;
	struct omap24xxcam_device *cam = ofh->cam;
	int rval;

	mutex_lock(&cam->mutex);
	rval = vidioc_int_g_parm(cam->sdev, a);
	mutex_unlock(&cam->mutex);

	return rval;
}

static int vidioc_s_parm(struct file *file, void *fh,
			 struct v4l2_streamparm *a)
{
	struct omap24xxcam_fh *ofh = fh;
	struct omap24xxcam_device *cam = ofh->cam;
	struct v4l2_streamparm old_streamparm;
	int rval;

	mutex_lock(&cam->mutex);
	if (cam->streaming) {
		rval = -EBUSY;
		goto out;
	}

	old_streamparm.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
	rval = vidioc_int_g_parm(cam->sdev, &old_streamparm);
	if (rval)
		goto out;

	rval = vidioc_int_s_parm(cam->sdev, a);
	if (rval)
		goto out;

	rval = omap24xxcam_sensor_if_enable(cam);
	/*
	 * Revert to old streaming parameters if enabling sensor
	 * interface with the new ones failed.
	 */
	if (rval)
		vidioc_int_s_parm(cam->sdev, &old_streamparm);

out:
	mutex_unlock(&cam->mutex);

	return rval;
}

/*
 *
 * File operations.
 *
 */

static unsigned int omap24xxcam_poll(struct file *file,
				     struct poll_table_struct *wait)
{
	struct omap24xxcam_fh *fh = file->private_data;
	struct omap24xxcam_device *cam = fh->cam;
	struct videobuf_buffer *vb;

	mutex_lock(&cam->mutex);
	if (cam->streaming != file) {
		mutex_unlock(&cam->mutex);
		return POLLERR;
	}
	mutex_unlock(&cam->mutex);

	mutex_lock(&fh->vbq.vb_lock);
	if (list_empty(&fh->vbq.stream)) {
		mutex_unlock(&fh->vbq.vb_lock);
		return POLLERR;
	}
	vb = list_entry(fh->vbq.stream.next, struct videobuf_buffer, stream);
	mutex_unlock(&fh->vbq.vb_lock);

	poll_wait(file, &vb->done, wait);

	if (vb->state == VIDEOBUF_DONE || vb->state == VIDEOBUF_ERROR)
		return POLLIN | POLLRDNORM;

	return 0;
}

static int omap24xxcam_mmap_buffers(struct file *file,
				    struct vm_area_struct *vma)
{
	struct omap24xxcam_fh *fh = file->private_data;
	struct omap24xxcam_device *cam = fh->cam;
	struct videobuf_queue *vbq = &fh->vbq;
	unsigned int first, last, size, i, j;
	int err = 0;

	mutex_lock(&cam->mutex);
	if (cam->streaming) {
		mutex_unlock(&cam->mutex);
		return -EBUSY;
	}
	mutex_unlock(&cam->mutex);
	mutex_lock(&vbq->vb_lock);

	/* look for first buffer to map */
	for (first = 0; first < VIDEO_MAX_FRAME; first++) {
		if (NULL == vbq->bufs[first])
			continue;
		if (V4L2_MEMORY_MMAP != vbq->bufs[first]->memory)
			continue;
		if (vbq->bufs[first]->boff == (vma->vm_pgoff << PAGE_SHIFT))
			break;
	}

	/* look for last buffer to map */
	for (size = 0, last = first; last < VIDEO_MAX_FRAME; last++) {
		if (NULL == vbq->bufs[last])
			continue;
		if (V4L2_MEMORY_MMAP != vbq->bufs[last]->memory)
			continue;
		size += vbq->bufs[last]->bsize;
		if (size == (vma->vm_end - vma->vm_start))
			break;
	}

	size = 0;
	for (i = first; i <= last && i < VIDEO_MAX_FRAME; i++) {
		struct videobuf_dmabuf *dma = videobuf_to_dma(vbq->bufs[i]);

		for (j = 0; j < dma->sglen; j++) {
			err = remap_pfn_range(
				vma, vma->vm_start + size,
				page_to_pfn(sg_page(&dma->sglist[j])),
				sg_dma_len(&dma->sglist[j]), vma->vm_page_prot);
			if (err)
				goto out;
			size += sg_dma_len(&dma->sglist[j]);
		}
	}

out:
	mutex_unlock(&vbq->vb_lock);

	return err;
}

static int omap24xxcam_mmap(struct file *file, struct vm_area_struct *vma)
{
	struct omap24xxcam_fh *fh = file->private_data;
	int rval;

	/* let the video-buf mapper check arguments and set-up structures */
	rval = videobuf_mmap_mapper(&fh->vbq, vma);
	if (rval)
		return rval;

	vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);

	/* do mapping to our allocated buffers */
	rval = omap24xxcam_mmap_buffers(file, vma);
	/*
	 * In case of error, free vma->vm_private_data allocated by
	 * videobuf_mmap_mapper.
	 */
	if (rval)
		kfree(vma->vm_private_data);

	return rval;
}

static int omap24xxcam_open(struct file *file)
{
	struct omap24xxcam_device *cam = omap24xxcam.priv;
	struct omap24xxcam_fh *fh;
	struct v4l2_format format;

	if (!cam || !cam->vfd)
		return -ENODEV;

	fh = kzalloc(sizeof(*fh), GFP_KERNEL);
	if (fh == NULL)
		return -ENOMEM;

	mutex_lock(&cam->mutex);
	if (cam->sdev == NULL || !try_module_get(cam->sdev->module)) {
		mutex_unlock(&cam->mutex);
		goto out_try_module_get;
	}

	if (atomic_inc_return(&cam->users) == 1) {
		omap24xxcam_hwinit(cam);
		if (omap24xxcam_sensor_enable(cam)) {
			mutex_unlock(&cam->mutex);
			goto out_omap24xxcam_sensor_enable;
		}
	}
	mutex_unlock(&cam->mutex);

	fh->cam = cam;
	mutex_lock(&cam->mutex);
	vidioc_int_g_fmt_cap(cam->sdev, &format);
	mutex_unlock(&cam->mutex);
	/* FIXME: how about fh->pix when there are more users? */
	fh->pix = format.fmt.pix;

	file->private_data = fh;

	spin_lock_init(&fh->vbq_lock);

	videobuf_queue_sg_init(&fh->vbq, &omap24xxcam_vbq_ops, NULL,
				&fh->vbq_lock, V4L2_BUF_TYPE_VIDEO_CAPTURE,
				V4L2_FIELD_NONE,
				sizeof(struct videobuf_buffer), fh);

	return 0;

out_omap24xxcam_sensor_enable:
	omap24xxcam_poweron_reset(cam);
	module_put(cam->sdev->module);

out_try_module_get:
	kfree(fh);

	return -ENODEV;
}

static int omap24xxcam_release(struct file *file)
{
	struct omap24xxcam_fh *fh = file->private_data;
	struct omap24xxcam_device *cam = fh->cam;

	atomic_inc(&cam->reset_disable);

	flush_scheduled_work();

	/* stop streaming capture */
	videobuf_streamoff(&fh->vbq);

	mutex_lock(&cam->mutex);
	if (cam->streaming == file) {
		cam->streaming = NULL;
		mutex_unlock(&cam->mutex);
		sysfs_notify(&cam->dev->kobj, NULL, "streaming");
	} else {
		mutex_unlock(&cam->mutex);
	}

	atomic_dec(&cam->reset_disable);

	omap24xxcam_vbq_free_mmap_buffers(&fh->vbq);

	/*
	 * Make sure the reset work we might have scheduled is not
	 * pending! It may be run *only* if we have users. (And it may
	 * not be scheduled anymore since streaming is already
	 * disabled.)
	 */
	flush_scheduled_work();

	mutex_lock(&cam->mutex);
	if (atomic_dec_return(&cam->users) == 0) {
		omap24xxcam_sensor_disable(cam);
		omap24xxcam_poweron_reset(cam);
	}
	mutex_unlock(&cam->mutex);

	file->private_data = NULL;

	module_put(cam->sdev->module);
	kfree(fh);

	return 0;
}

static struct v4l2_file_operations omap24xxcam_fops = {
	.ioctl	 = video_ioctl2,
	.poll	 = omap24xxcam_poll,
	.mmap	 = omap24xxcam_mmap,
	.open	 = omap24xxcam_open,
	.release = omap24xxcam_release,
};

/*
 *
 * Power management.
 *
 */

#ifdef CONFIG_PM
static int omap24xxcam_suspend(struct platform_device *pdev, pm_message_t state)
{
	struct omap24xxcam_device *cam = platform_get_drvdata(pdev);

	if (atomic_read(&cam->users) == 0)
		return 0;

	if (!atomic_read(&cam->reset_disable))
		omap24xxcam_capture_stop(cam);

	omap24xxcam_sensor_disable(cam);
	omap24xxcam_poweron_reset(cam);

	return 0;
}

static int omap24xxcam_resume(struct platform_device *pdev)
{
	struct omap24xxcam_device *cam = platform_get_drvdata(pdev);

	if (atomic_read(&cam->users) == 0)
		return 0;

	omap24xxcam_hwinit(cam);
	omap24xxcam_sensor_enable(cam);

	if (!atomic_read(&cam->reset_disable))
		omap24xxcam_capture_cont(cam);

	return 0;
}
#endif /* CONFIG_PM */

static const struct v4l2_ioctl_ops omap24xxcam_ioctl_fops = {
	.vidioc_querycap	= vidioc_querycap,
	.vidioc_enum_fmt_vid_cap	= vidioc_enum_fmt_vid_cap,
	.vidioc_g_fmt_vid_cap	= vidioc_g_fmt_vid_cap,
	.vidioc_s_fmt_vid_cap	= vidioc_s_fmt_vid_cap,
	.vidioc_try_fmt_vid_cap	= vidioc_try_fmt_vid_cap,
	.vidioc_reqbufs		= vidioc_reqbufs,
	.vidioc_querybuf	= vidioc_querybuf,
	.vidioc_qbuf		= vidioc_qbuf,
	.vidioc_dqbuf		= vidioc_dqbuf,
	.vidioc_streamon	= vidioc_streamon,
	.vidioc_streamoff	= vidioc_streamoff,
	.vidioc_enum_input	= vidioc_enum_input,
	.vidioc_g_input		= vidioc_g_input,
	.vidioc_s_input		= vidioc_s_input,
	.vidioc_queryctrl	= vidioc_queryctrl,
	.vidioc_g_ctrl		= vidioc_g_ctrl,
	.vidioc_s_ctrl		= vidioc_s_ctrl,
	.vidioc_g_parm		= vidioc_g_parm,
	.vidioc_s_parm		= vidioc_s_parm,
};

/*
 *
 * Camera device (i.e. /dev/video).
 *
 */

static int omap24xxcam_device_register(struct v4l2_int_device *s)
{
	struct omap24xxcam_device *cam = s->u.slave->master->priv;
	struct video_device *vfd;
	int rval;

	/* We already have a slave. */
	if (cam->sdev)
		return -EBUSY;

	cam->sdev = s;

	if (device_create_file(cam->dev, &dev_attr_streaming) != 0) {
		dev_err(cam->dev, "could not register sysfs entry\n");
		rval = -EBUSY;
		goto err;
	}

	/* initialize the video_device struct */
	vfd = cam->vfd = video_device_alloc();
	if (!vfd) {
		dev_err(cam->dev, "could not allocate video device struct\n");
		rval = -ENOMEM;
		goto err;
	}
	vfd->release = video_device_release;

	vfd->parent = cam->dev;

	strlcpy(vfd->name, CAM_NAME, sizeof(vfd->name));
	vfd->fops		 = &omap24xxcam_fops;
	vfd->ioctl_ops		 = &omap24xxcam_ioctl_fops;

	omap24xxcam_hwinit(cam);

	rval = omap24xxcam_sensor_init(cam);
	if (rval)
		goto err;

	if (video_register_device(vfd, VFL_TYPE_GRABBER, video_nr) < 0) {
		dev_err(cam->dev, "could not register V4L device\n");
		rval = -EBUSY;
		goto err;
	}

	omap24xxcam_poweron_reset(cam);

	dev_info(cam->dev, "registered device %s\n",
		 video_device_node_name(vfd));

	return 0;

err:
	omap24xxcam_device_unregister(s);

	return rval;
}

static void omap24xxcam_device_unregister(struct v4l2_int_device *s)
{
	struct omap24xxcam_device *cam = s->u.slave->master->priv;

	omap24xxcam_sensor_exit(cam);

	if (cam->vfd) {
		if (!video_is_registered(cam->vfd)) {
			/*
			 * The device was never registered, so release the
			 * video_device struct directly.
			 */
			video_device_release(cam->vfd);
		} else {
			/*
			 * The unregister function will release the
			 * video_device struct as well as
			 * unregistering it.
			 */
			video_unregister_device(cam->vfd);
		}
		cam->vfd = NULL;
	}

	device_remove_file(cam->dev, &dev_attr_streaming);

	cam->sdev = NULL;
}

static struct v4l2_int_master omap24xxcam_master = {
	.attach = omap24xxcam_device_register,
	.detach = omap24xxcam_device_unregister,
};

static struct v4l2_int_device omap24xxcam = {
	.module	= THIS_MODULE,
	.name	= CAM_NAME,
	.type	= v4l2_int_type_master,
	.u	= {
		.master = &omap24xxcam_master
	},
};

/*
 *
 * Driver initialisation and deinitialisation.
 *
 */

static int __devinit omap24xxcam_probe(struct platform_device *pdev)
{
	struct omap24xxcam_device *cam;
	struct resource *mem;
	int irq;

	cam = kzalloc(sizeof(*cam), GFP_KERNEL);
	if (!cam) {
		dev_err(&pdev->dev, "could not allocate memory\n");
		goto err;
	}

	platform_set_drvdata(pdev, cam);

	cam->dev = &pdev->dev;

	/*
	 * Impose a lower limit on the amount of memory allocated for
	 * capture. We require at least enough memory to double-buffer
	 * QVGA (300KB).
	 */
	if (capture_mem < 320 * 240 * 2 * 2)
		capture_mem = 320 * 240 * 2 * 2;
	cam->capture_mem = capture_mem;

	/* request the mem region for the camera registers */
	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	if (!mem) {
		dev_err(cam->dev, "no mem resource?\n");
		goto err;
	}
	if (!request_mem_region(mem->start, (mem->end - mem->start) + 1,
				pdev->name)) {
		dev_err(cam->dev,
			"cannot reserve camera register I/O region\n");
		goto err;
	}
	cam->mmio_base_phys = mem->start;
	cam->mmio_size = (mem->end - mem->start) + 1;

	/* map the region */
	cam->mmio_base = (unsigned long)
		ioremap_nocache(cam->mmio_base_phys, cam->mmio_size);
	if (!cam->mmio_base) {
		dev_err(cam->dev, "cannot map camera register I/O region\n");
		goto err;
	}

	irq = platform_get_irq(pdev, 0);
	if (irq <= 0) {
		dev_err(cam->dev, "no irq for camera?\n");
		goto err;
	}

	/* install the interrupt service routine */
	if (request_irq(irq, omap24xxcam_isr, 0, CAM_NAME, cam)) {
		dev_err(cam->dev,
			"could not install interrupt service routine\n");
		goto err;
	}
	cam->irq = irq;

	if (omap24xxcam_clock_get(cam))
		goto err;

	INIT_WORK(&cam->sensor_reset_work, omap24xxcam_sensor_reset_work);

	mutex_init(&cam->mutex);
	spin_lock_init(&cam->core_enable_disable_lock);

	omap24xxcam_sgdma_init(&cam->sgdma,
			       cam->mmio_base + CAMDMA_REG_OFFSET,
			       omap24xxcam_stalled_dma_reset,
			       (unsigned long)cam);

	omap24xxcam.priv = cam;

	if (v4l2_int_device_register(&omap24xxcam))
		goto err;

	return 0;

err:
	omap24xxcam_remove(pdev);
	return -ENODEV;
}

static int omap24xxcam_remove(struct platform_device *pdev)
{
	struct omap24xxcam_device *cam = platform_get_drvdata(pdev);

	if (!cam)
		return 0;

	if (omap24xxcam.priv != NULL)
		v4l2_int_device_unregister(&omap24xxcam);
	omap24xxcam.priv = NULL;

	omap24xxcam_clock_put(cam);

	if (cam->irq) {
		free_irq(cam->irq, cam);
		cam->irq = 0;
	}

	if (cam->mmio_base) {
		iounmap((void *)cam->mmio_base);
		cam->mmio_base = 0;
	}

	if (cam->mmio_base_phys) {
		release_mem_region(cam->mmio_base_phys, cam->mmio_size);
		cam->mmio_base_phys = 0;
	}

	kfree(cam);

	return 0;
}

static struct platform_driver omap24xxcam_driver = {
	.probe	 = omap24xxcam_probe,
	.remove	 = omap24xxcam_remove,
#ifdef CONFIG_PM
	.suspend = omap24xxcam_suspend,
	.resume	 = omap24xxcam_resume,
#endif
	.driver	 = {
		.name = CAM_NAME,
		.owner = THIS_MODULE,
	},
};

/*
 *
 * Module initialisation and deinitialisation
 *
 */

static int __init omap24xxcam_init(void)
{
	return platform_driver_register(&omap24xxcam_driver);
}

static void __exit omap24xxcam_cleanup(void)
{
	platform_driver_unregister(&omap24xxcam_driver);
}

MODULE_AUTHOR("Sakari Ailus <sakari.ailus@nokia.com>");
MODULE_DESCRIPTION("OMAP24xx Video for Linux camera driver");
MODULE_LICENSE("GPL");
module_param(video_nr, int, 0);
MODULE_PARM_DESC(video_nr,
		 "Minor number for video device (-1 ==> auto assign)");
module_param(capture_mem, int, 0);
MODULE_PARM_DESC(capture_mem, "Maximum amount of memory for capture "
		 "buffers (default 4800kiB)");

module_init(omap24xxcam_init);
module_exit(omap24xxcam_cleanup);