How to flush v4l2 drive

I read this mail posting about flush operation. https://www.mail-archive.com/linux-media@vger.kernel.org/msg41867.html My user side application talks to v4l2 driver like this, as an example, I put qbuf/dqbuf loop 10 times: open stream on for (int i = 0; i < 10; i++) qbuf dqbuf // pr

How to enable debug statements in v4l2 framework

Hi, In drivers/media/v4l2-core/videobuf2-core.c, I see debug printfs ilke this. I want to know how can I enable debug statements in v42l framework? #define dprintk(level, fmt, arg...)\ do {\

Question about 'flush' operation in v4l2 m2m driver framework

Hi, I read this email thread regarding 'flush operation'in v4l2 m2m driver framework: http://www.spinics.net/lists/linux-media/msg42944.html To implement a 'flush' operation, I should implement support for 'V4L2_DEC_CMD_STOP' command. Is my understanding correct?/ But my currently just implemen

Re: How can I feed more data to a stream after I stream on?

Thank you. If I am working on both the user side and the driver itself, why the buffer must contain a full image? Is that a limitation of v4l2 m2m framework? On Wed, Mar 19, 2014 at 12:22 AM, Hans Verkuil wrote: > On 03/19/2014 12:18 AM, m silverstri wrote: >> I am using v4l2 m2m fra

How can I feed more data to a stream after I stream on?

I am using v4l2 m2m framework to develop a resize driver. I have an image , pass it to the driver and it generated a resize output image. My v4l2 sequence is 1. qbuf OUTPUT, CAPTURE 2. stream on OUTPUT, CAPTURE 3. dqbuf OUTPUT, CAPTURE 4. stream off OUTPUT, CAPTURE this works if i have a full fra

Re: Question about set format call check for vb2_is_busy

On Mon, Mar 10, 2014 at 12:21 AM, Hans Verkuil wrote: > On 03/10/2014 08:02 AM, m silverstri wrote: >> Hi, >> >> I am studying v4l2 m2m driver example. I want to know why the set >> format function in the example fails when it is called again after >> user a

Question about set format call check for vb2_is_busy

Hi, I am studying v4l2 m2m driver example. I want to know why the set format function in the example fails when it is called again after user application req_buf? In set format function checks for vb2_is_busy(vq) and that function returns true after user space app calls req_buf. For example in he

Purpose of mem_ops in source and destination queue

Hi, I think the sequence of using a V4L2 codec mem2mem driver is like this: 1. queue buffer for input buffer 2. queue buffer for output buffer 3. Streamon OUTPUT plane 4. Streamoff Capture plane 5. dequeue buffer for input buffer 6. dequeue buffer for output buffer And for the driver implementati

When do I need to call 'v4l2_m2m_get_next_job()' in stop_streaming

Hi, Can you please tell me when do I need to call 'v4l2_m2m_get_next_job() in stop streaming/job_abort? I find 2 examples of v4l2 m2m driver, they implement stop_streaming/job_abort differently. One call v4l2_m2m_get_next_job() in stop streaming/job_abort? https://android.googlesource.com/kerne

Re: Looking for example to use samsung jpeg v4l2 mem2mem driver

Thanks for the test application. But I don' see the test directory in the repository mention here: http://git.infradead.org/users/kmpark/public-apps/tree/refs/heads/master Thank you again. On Wed, Jan 8, 2014 at 12:54 PM, Sylwester Nawrocki wrote: > Hi, > > > On 01/01

Re: How can I find out what is the driver for device node '/dev/video11'

Sylwester, Devin, Thank you. On Wed, Jan 8, 2014 at 1:19 PM, Sylwester Nawrocki wrote: > On 01/08/2014 08:15 PM, m silverstri wrote: >> >> Thanks. >> >> I am studying android source code. >> From here, it has code which open("/dev/video11", O_RD

Re: How can I find out what is the driver for device node '/dev/video11'

de for device '/dev/video11'. Thank you very much. On Wed, Jan 8, 2014 at 11:08 AM, Devin Heitmueller wrote: > On Wed, Jan 8, 2014 at 2:03 PM, m silverstri > wrote: >> Thanks. I don't have the a running hardware. >> If I can only search within the code space, h

Re: How can I find out what is the driver for device node '/dev/video11'

8, 2014 at 1:50 PM, m silverstri > wrote: >> In linux kernel, a device (e.g. codec) can register as a file (e.g. >> /dev/video11). >> >> How can I find out from the code which driver is registered as >> '/dev/video11'. i.e. what is the driver will be invo

How can I find out what is the driver for device node '/dev/video11'

In linux kernel, a device (e.g. codec) can register as a file (e.g. /dev/video11). How can I find out from the code which driver is registered as '/dev/video11'. i.e. what is the driver will be invoked when I open('/dev/video11', O_RDWR,0) in my user space code? -- To unsubscribe from this list: s

Re: How to enable "CONFIG_V4L2_MEM2MEM_DEV"

#x27;. I appreciate if I can get help on this. Thank you. On Mon, Jan 6, 2014 at 1:30 PM, Fabio Estevam wrote: > On Mon, Jan 6, 2014 at 7:22 PM, m silverstri > wrote: >> I have added 'CONFIG_V4L2_MEM2MEM_DEV=y' to my 'imx_v6_v7_defconfig' >> and do a &

How to enable "CONFIG_V4L2_MEM2MEM_DEV"

I have added 'CONFIG_V4L2_MEM2MEM_DEV=y' to my 'imx_v6_v7_defconfig' and do a "make ARCH=arm CROSS_COMPILE=/usr/bin/arm-linux-gnueabi- imx_v6_v7_defconfig", I don't see CONFIG_V4L2_MEM2MEM_DEV being set to 'y' in .config that was automatically generated. I think I am making changes to the right '

Question about 'Generic V4L2 Andriod camera HAL' slide

Hi, I google and find the presentation for Generic V4L2 Andriod camera HAL, in there it said * "A VEU mem2mem driver has been written to convert YUV camera output to a 16-bit RGB format" and * "A test program from Sylwester has been xed and extended." Can you please tell me where I can find the