Linux/AM5728: Dual camera demo

xiaoyan Chi

Expert 1395 points

Part Number: AM5728

Tool/software: Linux

Hi,

My sdk is 4.2 .I 've try to develop dual-camera-demo.

Below is default_parameters in loopback.c I changed:

	/* Main camera */
	cap0_device.memory_mode = V4L2_MEMORY_DMABUF;
	cap0_device.num_buffers = NBUF;
	strcpy(cap0_device.dev_name,"/dev/video5");
	strcpy(cap0_device.name,"Capture 0");
	cap0_device.buffers = NULL;
	cap0_device.fmt.fmt.pix.pixelformat = V4L2_PIX_FMT_YUYV;
	cap0_device.width = 1920;
	cap0_device.height = 1080;

	/* PiP camera */
	cap1_device.memory_mode = V4L2_MEMORY_DMABUF;
	cap1_device.num_buffers = NBUF;
	strcpy(cap1_device.dev_name,"/dev/video1");
	strcpy(cap1_device.name,"Capture 1");
	cap1_device.buffers = NULL;
	cap1_device.fmt.fmt.pix.pixelformat = V4L2_PIX_FMT_YUYV;
	cap1_device.width = 704;
	cap1_device.height = 288;

	/* Set the default parameters for device options */
	status.main_cam=0;
	status.num_cams=2;

I got an error with :

ERROR:drm_reserve_plane:632: plane couldn't be reserved

......

ERROR:drm_add_plane_property:547: drm obeject properties for plane type is NULL

If I config

status.num_cams=2;
to

status.num_cams=1;

It will display the camera successfully.

I try to check the plane with modetest -p.There are 4 planes.

I find this error is happen on :

drm_reserve_plane() in loopback.c

if(type_val == DRM_PLANE_TYPE_OVERLAY){
ptr_plane_id[idx++] = plane_id;
}

Only one plane is DRM_PLANE_TYPE_OVERLAY which can be reserved.

Thanks,

Cxy.

over 7 years ago

0 Margarita Gashova over 7 years ago

TI__Guru* 80190 points

Hello,

I am sorry but what is the question?

BR
Margarita

0 xiaoyan Chi over 7 years ago in reply to Margarita Gashova

Expert 1395 points

Hi，
I puzzled why does the plane can't be reserved ?
There are 4 planes ,but only one is DRM_PLANE_TYPE_OVERLAY .
Can I config other planes to DRM_PLANE_TYPE_OVERLAY ?
And how can I do that ?

0 Margarita Gashova over 7 years ago in reply to xiaoyan Chi

TI__Guru* 80190 points

Hello,

I understand, let me check I will get back to you with answer.

Best Regards,
Margarita

0 Manisha Agrawal over 7 years ago in reply to Margarita Gashova

TI__Mastermind 22946 points

Are you running the demo on your own hardware board? How many displays connected to the board? There are overall 4 hardware planes. One plane is owned by CRTC (primary plane) per display. If there are two displays connected, then they consume two hardware planes. Rest of the planes are available for overlay plane.

Which QPA are you using - linuxfb or eglfs?

0 xiaoyan Chi over 7 years ago in reply to Manisha Agrawal

Expert 1395 points

Hi,

Thanks manisha.

Our own board has configure three displays.I disable the other 2 displays in device tree file :

display0 = &hdmi0;
// display1 = &cameralink_1;
// display2 = &cameralink_2;

Then I could use the other planes as overlay plane.

My understanding is that : 1 Display -> 1 crtc -> 1 plane -> 1 fb

They are bind together ,right ?

Does primary plane can be configure as overlay plane?

0 Manisha Agrawal over 7 years ago in reply to xiaoyan Chi

TI__Mastermind 22946 points

There are two types of planes, DRM_PLANE_TYPE_PRIMARY and DRM_PLANE_TYPE_OVERLAY. PRIMARY plane can not be configured as overlay planes.

1 Display -> 1 crtc -> 1 DRM_PLANE_TYPE_PRIMARY. Leftover hardware planes can be used for overlay.

Processors

Processors forum

Linux/AM5728: Dual camera demo