开发板摄像头图像采集调试！！

内核版本为Linux-2.6.18

这两天在开发板上调试摄像头遇到的些问题：

 

1、mmap.frame没设定好，造成的错误信息：

 

the framebuffer device was opened successfully;

error reading fixed information.

640,480, 16bpp,xoffset= 0,yoffset= 0

the framebuffer device was mapped to memory successfully.

 

/mnt/hgfs/Image/gspcav1-20071224/gspca_core.c: [spca5xx_set_light_freq:1932] Sensor currently not support light frequency banding filters.

/mnt/hgfs/Image/gspcav1-20071224/gspca_core.c: [gspca_set_isoc_ep:945] ISO EndPoint found 0x81 AlternateSet 8

 

the video device was opened successfully.

Sonix PcCam, Type:1  (((#define VID_TYPE_CAPTURE  1  /* Can capture */)))

Maxwidth:640, Maxheight:480

Minwidth:160, Minheight:120

Channels:1, Audios:0

Unable to handle kernel NULL pointer dereference at virtual address 00000004

pgd = c3c04000

[00000004] *pgd=33884031, *pte=00000000, *ppte=00000000

Internal error: Oops: 817 [#5]

Modules linked in: gspca zlgffs zlgfs

CPU: 0

PC is at prepare_to_wait+0x40/0x6c

LR is at 0xc3a70034

pc : [<c005016c>]    lr : [<c3a70034>]    Tainted: PF    

sp : c3a71df4  ip : c3a71e3c  fp : c3a71e04

r10: 00000020  r9 : bf05a2b8  r8 : c3a70000

r7 : c04e4000  r6 : c3a71e30  r5 : 00000002  r4 : 00000001

r3 : 00000000  r2 : 40000013  r1 : c3a71e30  r0 : c04e7bec

Flags: nZCv  IRQs off  FIQs on  Mode SVC_32  Segment user

Control: 717F  Table: 33C04000  DAC: 00000015

Process source (pid: 1012, stack limit = 0xc3a70250)

Stack: (0xc3a71df4 to 0xc3a72000)

1de0:                                              c04e59d0 c3a71e6c c3a71e08 

1e00: bf020620 c005013c c04e51a8 c3a71f2c c3a71e1c bf02c404 00000000 00000000 

1e20: c3480360 c0050270 c3a71e3c c3a71e3c 00000000 c3480360 c0050270 00000000 

1e40: c3a71e3c 00000000 beec0d78 fffffff2 00000000 00000000 40047612 00000000 

1e60: c3a71f2c c3a71e70 c01753c8 bf01fac4 00000001 00000000 c3a71e84 c04364e0 

1e80: c0569870 00000002 000000f0 00000140 00000003 0000002a 00000000 00000000 

1ea0: c3a71f28 c3a70000 0000002a c3a71ecc c3a71ebc c3a71ed4 c3a71ec4 c00452fc 

1ec0: c00452b8 00000000 c3a71f24 c3a71ed8 c00459fc c3480360 c3a71f0c c3a71edc 

1ee0: c3a71edc c3480360 00000001 00000000 00000000 c3a71fb0 c3a70000 0000001e 

1f00: c3a71f34 c04364e0 ffffffe7 40047612 00000000 c0025f44 c3a70000 4016864c 

1f20: c3a71f40 c3a71f30 bf020a00 c0175218 bf01fab4 c3a71f5c c3a71f44 c008f1bc 

1f40: bf0209f4 c04364e0 beec0d78 00000004 c3a71f84 c3a71f60 c008f45c c008f158 

1f60: c3a71f8c c0025df4 c04364e0 fffffff7 40047612 00000036 c3a71fa4 c3a71f88 

1f80: c008f4bc c008f1dc 00000000 beec0e34 000090d4 00000001 00000000 c3a71fa8 

1fa0: c0025da0 c008f48c beec0e34 000090d4 00000004 40047612 beec0d78 beec0d78 

1fc0: beec0e34 000090d4 00000001 00009130 00008eac 00000000 4016864c bee2a860 

1fe0: 00011530 bee2a848 00008b6c 4010f644 60000010 00000004 ffffffff ffffffff 

Backtrace: 

[<c005012c>] (prepare_to_wait+0x0/0x6c) from [<bf020620>] (spca5xx_do_ioctl+0xb6c/0xf30 [gspca])

 r4 = C04E59D0 

[<bf01fab4>] (spca5xx_do_ioctl+0x0/0xf30 [gspca]) from [<c01753c8>] (video_usercopy+0x1c0/0x2b0)

[<c0175208>] (video_usercopy+0x0/0x2b0) from [<bf020a00>] (spca5xx_ioctl+0x1c/0x24 [gspca])

[<bf0209e4>] (spca5xx_ioctl+0x0/0x24 [gspca]) from [<c008f1bc>] (do_ioctl+0x74/0x84)

[<c008f148>] (do_ioctl+0x0/0x84) from [<c008f45c>] (vfs_ioctl+0x290/0x2b0)

 r6 = 00000004  r5 = BEEC0D78  r4 = C04364E0 

[<c008f1cc>] (vfs_ioctl+0x0/0x2b0) from [<c008f4bc>] (sys_ioctl+0x40/0x5c)

 r7 = 00000036  r6 = 40047612  r5 = FFFFFFF7  r4 = C04364E0

[<c008f47c>] (sys_ioctl+0x0/0x5c) from [<c0025da0>] (ret_fast_syscall+0x0/0x2c)

 r6 = 00000001  r5 = 000090D4  r4 = BEEC0E34 

Code: e153000c 05903000 e3cded7f 0581300c (0583c004) 

/mnt/hgfs/Image/gspcav1-20071224/gspca_core.c: [spca50x_move_data:1611] ISOC data error: [0] len=0, status=-18 

 

/mnt/hgfs/Image/gspcav1-20071224/gspca_core.c: [spca50x_move_data:1611] ISOC data error: [1] len=0, status=-18 

 

/mnt/hgfs/Image/gspcav1-20071224/gspca_core.c: [spca50x_move_data:1611] ISOC data error: [2] len=0, status=-18 

 

/mnt/hgfs/Image/gspcav1-20071224/gspca_core.c: [spca50x_move_data:1611] ISOC data error: [3] len=0, status=-18 

 

/mnt/hgfs/Image/gspcav1-20071224/gspca_core.c: [spca50x_move_data:1611] ISOC data error: [4] len=0, status=-18 

 

/mnt/hgfs/Image/gspcav1-20071224/gspca_core.c: [spca50x_move_data:1611] ISOC data error: [5] len=1019, status=-114 

 

【注解】

简单分析：普通摄像头一般都是double frames，因此在使用过程中不能将mmap.frame的值超过1，即可设为0、1，此值为当前摄像头采集帧的序号。

struct video_mmap

{

unsigned intframe; /* Frame (0 - n) for double buffer */

int height,width;

unsigned intformat; /* should be VIDEO_PALETTE_* */

};

frame :设置当前是第几帧、height,width:设置图象的高和宽、format :颜色模式