framebuffer overlay
Hello,
I am trying to write a driver for a camera using the new soc_camera in the mainline kernel the output is the overlay framebuffer (pxa270) and i would like to use the overlay output feature of v4l2 framework, but the framebuffer does not expose itself as a output device (not yet).
Are there any fb that i can use as an example for this?
From looking at the driver code, it seems like the generic code of fbmem.c needs a v4l2 device. Is this in the right ballpark?
Thanks,
Ryan
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Quoted 7 lines · Ryan Raasch
Hello,
I am trying to write a driver for a camera using the new
soc_camerain the mainline kernel the output is the overlay framebuffer (pxa270) and i would like to use the overlay output feature of v4l2 framework, but the framebuffer does not expose itself as a output device (not yet).
Hi Ryan,
As far as I know the framebuffer of PXA2 even PXA3 can't be categorized in a overlay device.
To be able to get used as overlay device by camera interface, I think there should be a direct FIFO between camera and framebuffer which means there is no need to copy memory from camera to fb. But unfortunately PXA architecture is not supporting this kind of feature. Cheers,
Nate
Quoted 13 lines
Are there any fb that i can use as an example for this?
From looking at the driver code, it seems like the generic code of
fbmem.cneeds a v4l2 device. Is this in the right ballpark?Thanks,
Ryan--
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Signature · 8 lines
= DongSoo, Nathaniel Kim Engineer Mobile S/W Platform Lab. Digital Media & Communications R&D Centre Samsung Electronics CO., LTD. e-mail : [email protected] [email protected]
Thanks for the reply!
Quoted 8 lines · Nathaniel Kim
Quoted 7 lines · Ryan Raasch
Hello,
I am trying to write a driver for a camera using the new
soc_camerain the mainline kernel the output is the overlay framebuffer (pxa270) and i would like to use the overlay output feature of v4l2 framework, but the framebuffer does not expose itself as a output device (not yet).
Quoted 4 lines
Hi Ryan,
As far as I know the framebuffer of PXA2 even PXA3 can't be categorized in a overlay device.
The pxa2 and pxa3 both have 3 framebuffers (4 if hardware curser included). There is the main fb, and 2 overlay framebuffers.
The overlay 2 has hardware accelerated ycbcr decoding (which i use now with a camera using dma). And the overlay 1 can be used only with the various types of RGB.
We have a solution which uses dma to copy the captured video from the camera sensor (mmap'd), directly to the mmap'd memory of the overlay. All occuring without user intervention.
Quoted 4 lines
To be able to get used as overlay device by camera interface, I think there should be a direct FIFO between camera and framebuffer which means there is no need to copy memory from camera to fb. But unfortunately PXA architecture is not supporting this kind of feature.
With the above there is no need for FIFO, the dma is directly copying the received camera data to the selected framebuffer.
Ryan
Quoted 22 lines
Cheers,
Nate
Quoted 13 lines
Are there any fb that i can use as an example for this?
From looking at the driver code, it seems like the generic code of
fbmem.cneeds a v4l2 device. Is this in the right ballpark?Thanks,
Ryan--
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Unsubscribe mailto:[email protected]?subject=unsubscribe
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Quoted 37 lines · Ryan Raasch
Thanks for the reply!
Quoted 12 lines · Nathaniel Kim
Quoted 10 lines · Ryan Raasch
Hello,
I am trying to write a driver for a camera using the new
soc_camerain the
mainline kernel the output is the overlay framebuffer (pxa270) and i would
like to use the overlay output feature of v4l2 framework, but the framebuffer does not expose itself as a output device (not yet).Quoted 4 lines
Hi Ryan,
As far as I know the framebuffer of PXA2 even PXA3 can't be categorized in a overlay device.
The pxa2 and pxa3 both have 3 framebuffers (4 if hardware curser included). There is the main fb, and 2 overlay framebuffers.
The overlay 2 has hardware accelerated ycbcr decoding (which i use now with a camera using dma). And the overlay 1 can be used only with the various types of RGB.
We have a solution which uses dma to copy the captured video from the camera sensor (mmap'd), directly to the mmap'd memory of the overlay. All occuring without user intervention.
Quoted 4 lines
To be able to get used as overlay device by camera interface, I think there should be a direct FIFO between camera and framebuffer which means there is no need to copy memory from camera to fb. But unfortunately PXA architecture is not supporting this kind of feature.
Quoted 5 lines
With the above there is no need for FIFO, the dma is directly copying the received camera data to the selected framebuffer.
Ryan
Cool.
So, that means you need a SoC hardware based reference code right? (because pxa is also a SoC)
I think there is not so many choices that you can put on the table. In my experience, OMP3 camera interface is supporting overlay feature through omap_vout I guess. I think it is not obvious in SoC H/W platform about *what is overlay device* and *how to use* them.
And about omap3 camera interface driver, it is not in the mainline kernel yet. For the camera interface code you need to look into Sakari's gitorious repository and for omap_vout you need to look for Hardik's repository or any repository he is working on..I guess. I'm also trying to figure out the best way to use overlay feature on samsung's new cpu named S5PC1XX.
The most complicated part of this job is the whole thing is happening in a single piece of chip and need to figure out the standardized way for compatibility. I wish you luck :-)
Cheers,
Nate
Quoted 25 lines
Quoted 24 lines
Cheers,
Nate
Quoted 15 lines
Are there any fb that i can use as an example for this?
From looking at the driver code, it seems like the generic code of
fbmem.c
needs a v4l2 device. Is this in the right ballpark?Thanks,
Ryan--
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Signature · 8 lines
= DongSoo, Nathaniel Kim Engineer Mobile S/W Platform Lab. Digital Media & Communications R&D Centre Samsung Electronics CO., LTD. e-mail : [email protected] [email protected]
I have another question.
Has there been any discussion on any type of generic framebuffer v4l2 device (output device), like a gstreamer sink (like the soc_camera)?
From this perspective, when the frame buffer registers itself, it could just *add* the capabilities, and allow the fb.c to handle many of the logistics.
I am developing for a system where we do not use X and use the framebuffer directly (E17). It would be nice to fit any of the framebuffers into a *neat* v4l2 package for any app to use (gstreamer, mplayer).
And with our camera, gstreamer, etc. could just be a command line away from live streaming :)
Thanks,
Ryan
Quoted 87 lines · Nathaniel Kim
Quoted 29 lines · Ryan Raasch
Thanks for the reply!
Quoted 10 lines · Nathaniel Kim
Quoted 9 lines · Ryan Raasch
Hello,
I am trying to write a driver for a camera using the new
soc_camerain the
mainline kernel the output is the overlay framebuffer (pxa270) and i would
like to use the overlay output feature of v4l2 framework, but the framebuffer does not expose itself as a output device (not yet).Quoted 4 lines
Hi Ryan,
As far as I know the framebuffer of PXA2 even PXA3 can't be categorized in a overlay device.
The pxa2 and pxa3 both have 3 framebuffers (4 if hardware curser included). There is the main fb, and 2 overlay framebuffers.
The overlay 2 has hardware accelerated ycbcr decoding (which i use now with a camera using dma). And the overlay 1 can be used only with the various types of RGB.
We have a solution which uses dma to copy the captured video from the camera sensor (mmap'd), directly to the mmap'd memory of the overlay. All occuring without user intervention.
Quoted 9 lines
Quoted 4 lines
To be able to get used as overlay device by camera interface, I think there should be a direct FIFO between camera and framebuffer which means there is no need to copy memory from camera to fb. But unfortunately PXA architecture is not supporting this kind of feature.
With the above there is no need for FIFO, the dma is directly copying the received camera data to the selected framebuffer.
Ryan
Cool.
So, that means you need a SoC hardware based reference code right? (because pxa is also a SoC)
I think there is not so many choices that you can put on the table. In my experience, OMP3 camera interface is supporting overlay feature throughomap_voutI guess. I think it is not obvious in SoC H/W platform about *what is overlay device* and *how to use* them.And about omap3 camera interface driver, it is not in the mainline kernel yet. For the camera interface code you need to look into Sakari's gitorious repository and for
omap_voutyou need to look for Hardik's repository or any repository he is working on..I guess. I'm also trying to figure out the best way to use overlay feature on samsung's new cpu named S5PC1XX.The most complicated part of this job is the whole thing is happening in a single piece of chip and need to figure out the standardized way for compatibility. I wish you luck :-)
Cheers,Nate
Quoted 22 lines
Quoted 22 lines
Cheers,
Nate
Quoted 15 lines
Are there any fb that i can use as an example for this?
From looking at the driver code, it seems like the generic code of
fbmem.c
needs a v4l2 device. Is this in the right ballpark?Thanks,
Ryan--
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Unsubscribe mailto:[email protected]?subject=unsubscribe
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