[linux-uvc-devel] absolute exposure reads as zero all the time

[Ryan E. <Ry...@en...>]

Hi uvc-devel list,


I'm upgrading one of my computers to the latest and greatest. This system is using a camera "0403:602a Future Technology Devices International" specifically and was working fine on an older kernel (4.4.8 specifically). When I went to a modern version I lost the ability to read back exposure_absolute from v4l2-ctl. Someone added a UVC_CTRL_FLAG_AUTO_UPDATE to UVC_CT_EXPOSURE_TIME_ABSOLUTE_CONTROL commit 1ab8c3fc750321726313b222230343de897744b1. It seemed to be a fix to an issue reading the exposure back when the camera supports auto exposure. This change seemed to have broken my camera and I'm wondering if mine is the only one. My camera doesn't support any auto exposure controls and I do not have another model that has no auto exposure controls.


Is there anyone on the list that has a camera with no automatic exposure controls and is able to read back the absolute exposure after setting it? I'm trying to figure out if only my camera has a problem or if this is a bug on camera models with no auto exposure controls.

Ryan Esty