i.MX ProcessorsのトピックCan't apply gamma correction to /dev/fb2

Can't apply gamma correction to /dev/fb2

mirkoardinghi1 — Wed, 09 Aug 2017 10:29:09 GMT

I need to change the GAMMA value (with the ioctl MXCFB_SET_GAMMA) to framebuffer /dev/fb2

I developed a simple program with whom I can successfully change the gamma value to /dev/fb0 but when I try with /dev/fb2 I obtain the following error:

Ioctl MXCFB_SET_GAMMA fail!

I'm using a imx6duallite with linux yocto (krogoth version)

Any help?

Re: Can't apply gamma correction to /dev/fb2

igorpadykov — Wed, 09 Aug 2017 23:23:33 GMT

Hi Mirko

for gamma correction examples one can look at

ipu-examples release notes - v0.1

also one can try unblank fb2 like

echo 0 > /sys/class/graphics/fb2/blank

Best regards
igor
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Re: Can't apply gamma correction to /dev/fb2

mirkoardinghi1 — Mon, 28 Aug 2017 09:48:19 GMT

Hi Igor,

I tested the ipu-examples but the problem remains. In this test (in mx6/framebuffer/example1/) has been tested only the gamma for /dev/fb0, if I change /dev/fb0 with /dev/fb2 I obtain the same failure:

Ioctl MXCFB_SET_GAMMA fail!

Thanks in advance.

Mirko