Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > linux.kernel > #1656945

Re: [PATCH v7 16/34] [media] add Omnivision OV5640 sensor driver

From Pavel Machek <pavel@ucw.cz>
Newsgroups linux.kernel
Subject Re: [PATCH v7 16/34] [media] add Omnivision OV5640 sensor driver
Date 2017-06-04 00:20 +0200
Message-ID <tOpyN-4jB-3@gated-at.bofh.it> (permalink)
References (2 earlier) <tNhWG-Ge-19@gated-at.bofh.it> <tNtEu-9b-3@gated-at.bofh.it> <tOn3X-2HQ-13@gated-at.bofh.it> <tOnnj-2O9-1@gated-at.bofh.it> <tOpfs-3WE-3@gated-at.bofh.it>
Organization linux.* mail to news gateway

Show all headers | View raw

[Multipart message — attachments visible in raw view] - view raw

Hi!

> > > According to the docs V4L2_CID_EXPOSURE_ABSOLUTE is in 100 usec units.
> > > 
> > >  OTOH V4L2_CID_EXPOSURE has no defined unit, so it's a better fit IMO.
> > > >Way more drivers appear to be using EXPOSURE than EXPOSURE_ABSOLUTE, too.
> > > 
> > > Done, switched to V4L2_CID_EXPOSURE. It's true, this control is not
> > > taking 100 usec units, so unit-less is better.
> > 
> > Thanks. If you know the units, it would be of course better to use
> > right units...
> 
> Steve: what's the unit in this case? Is it lines or something else?
> 
> Pavel: we do need to make sure the user space will be able to know the unit,
> too. It's rather a case with a number of controls: the unit is known but
> there's no API to convey it to the user.
> 
> The exposure is a bit special, too: granularity matters a lot on small
> values. On most other controls it does not.

Yeah. Basically problem with exposure is that the control is
logarithmic; by using linear scale we got too much resolution at long
times and too little resolution at short times.

(Plus, 100 usec ... n900 can do times _way_ shorter than that.)

Anyway, even u32 gives us enough range, but I so the linear/log
confusion does not matter. But it would be nicer if values were in 10
usec or usec, not 100 usec... 

								Pavel
-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html

Back to linux.kernel | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread

Thread

[PATCH v7 00/34] i.MX Media Driver Steve Longerbeam <slongerbeam@gmail.com> - 2017-05-25 02:40 +0200
  [PATCH v7 05/34] ARM: dts: imx6qdl: Add compatible, clocks, irqs to MIPI CSI-2 node Steve Longerbeam <slongerbeam@gmail.com> - 2017-05-25 02:40 +0200
  [PATCH v7 21/34] media: imx: Add Capture Device Interface Steve Longerbeam <slongerbeam@gmail.com> - 2017-05-25 02:40 +0200
  [PATCH v7 25/34] media: imx: Add MIPI CSI-2 Receiver subdev driver Steve Longerbeam <slongerbeam@gmail.com> - 2017-05-25 02:40 +0200
  [PATCH v7 13/34] ARM: dts: imx6-sabreauto: add pinctrl for gpt input capture Steve Longerbeam <slongerbeam@gmail.com> - 2017-05-25 02:40 +0200
  [PATCH v7 31/34] media: imx: csi: add frame size/interval enumeration Steve Longerbeam <slongerbeam@gmail.com> - 2017-05-25 02:40 +0200
  [PATCH v7 14/34] ARM: dts: imx6-sabreauto: add the ADV7180 video decoder Steve Longerbeam <slongerbeam@gmail.com> - 2017-05-25 02:40 +0200
  [PATCH v7 27/34] media: imx: csi: add support for bayer formats Steve Longerbeam <slongerbeam@gmail.com> - 2017-05-25 02:40 +0200
  [PATCH v7 08/34] ARM: dts: imx6qdl-sabrelite: remove erratum ERR006687 workaround Steve Longerbeam <slongerbeam@gmail.com> - 2017-05-25 02:40 +0200
  [PATCH v7 28/34] media: imx: csi: increase burst size for YUV formats Steve Longerbeam <slongerbeam@gmail.com> - 2017-05-25 02:40 +0200
  [PATCH v7 30/34] media: imx: csi: add sink selection rectangles Steve Longerbeam <slongerbeam@gmail.com> - 2017-05-25 02:40 +0200
  [PATCH v7 09/34] ARM: dts: imx6-sabrelite: add OV5642 and OV5640 camera sensors Steve Longerbeam <slongerbeam@gmail.com> - 2017-05-25 02:40 +0200
  [PATCH v7 19/34] media: Add userspace header file for i.MX Steve Longerbeam <slongerbeam@gmail.com> - 2017-05-25 02:40 +0200
  [PATCH v7 12/34] ARM: dts: imx6-sabreauto: add reset-gpios property for max7310_b Steve Longerbeam <slongerbeam@gmail.com> - 2017-05-25 02:40 +0200
  [PATCH v7 06/34] ARM: dts: imx6qdl: Add video multiplexers, mipi_csi, and their connections Steve Longerbeam <slongerbeam@gmail.com> - 2017-05-25 02:40 +0200
  [PATCH v7 15/34] add mux and video interface bridge entity functions Steve Longerbeam <slongerbeam@gmail.com> - 2017-05-25 02:40 +0200
    Re: [PATCH v7 15/34] add mux and video interface bridge entity  functions Hans Verkuil <hverkuil@xs4all.nl> - 2017-05-29 15:40 +0200
      Re: [PATCH v7 15/34] add mux and video interface bridge entity  functions Hans Verkuil <hverkuil@xs4all.nl> - 2017-05-29 16:00 +0200
      Re: [PATCH v7 15/34] add mux and video interface bridge entity  functions Philipp Zabel <p.zabel@pengutronix.de> - 2017-05-29 16:00 +0200
  [PATCH v7 29/34] media: imx: csi: add frame skipping support Steve Longerbeam <slongerbeam@gmail.com> - 2017-05-25 02:40 +0200
  [PATCH v7 04/34] ARM: dts: imx6qdl: add multiplexer controls Steve Longerbeam <slongerbeam@gmail.com> - 2017-05-25 02:40 +0200
  [PATCH v7 26/34] ARM: imx_v6_v7_defconfig: Enable staging video4linux drivers Steve Longerbeam <slongerbeam@gmail.com> - 2017-05-25 02:40 +0200
  [PATCH v7 01/34] dt-bindings: Add bindings for video-multiplexer device Steve Longerbeam <slongerbeam@gmail.com> - 2017-05-25 02:40 +0200
  [PATCH v7 23/34] media: imx: Add VDIC subdev driver Steve Longerbeam <slongerbeam@gmail.com> - 2017-05-25 02:40 +0200
  [PATCH v7 18/34] platform: video-mux: include temporary mmio-mux support Steve Longerbeam <slongerbeam@gmail.com> - 2017-05-25 02:40 +0200
    Re: [PATCH v7 18/34] platform: video-mux: include temporary mmio-mux  support kbuild test robot <lkp@intel.com> - 2017-05-25 10:00 +0200
    [PATCH] platform: video-mux: fix ptr_ret.cocci warnings kbuild test robot <lkp@intel.com> - 2017-05-25 10:00 +0200
  [PATCH v7 17/34] platform: add video-multiplexer subdevice driver Steve Longerbeam <slongerbeam@gmail.com> - 2017-05-25 02:40 +0200
  [PATCH v7 34/34] media: imx: Drop warning upon multiple S_STREAM disable calls Steve Longerbeam <slongerbeam@gmail.com> - 2017-05-25 02:40 +0200
  [PATCH v7 02/34] [media] dt-bindings: Add bindings for i.MX media driver Steve Longerbeam <slongerbeam@gmail.com> - 2017-05-25 02:50 +0200
  [PATCH v7 10/34] ARM: dts: imx6-sabresd: add OV5642 and OV5640 camera sensors Steve Longerbeam <slongerbeam@gmail.com> - 2017-05-25 02:50 +0200
  Re: [PATCH v7 00/34] i.MX Media Driver Hans Verkuil <hverkuil@xs4all.nl> - 2017-05-29 15:50 +0200
    Re: [PATCH v7 00/34] i.MX Media Driver Philipp Zabel <p.zabel@pengutronix.de> - 2017-05-29 16:20 +0200
      Re: [PATCH v7 00/34] i.MX Media Driver Hans Verkuil <hverkuil@xs4all.nl> - 2017-05-29 16:30 +0200
        Re: [PATCH v7 00/34] i.MX Media Driver Hans Verkuil <hverkuil@xs4all.nl> - 2017-05-29 17:30 +0200
    Re: [PATCH v7 00/34] i.MX Media Driver Sakari Ailus <sakari.ailus@iki.fi> - 2017-05-29 17:40 +0200
      Re: [PATCH v7 00/34] i.MX Media Driver Hans Verkuil <hverkuil@xs4all.nl> - 2017-05-29 18:30 +0200
      Re: [PATCH v7 00/34] i.MX Media Driver Steve Longerbeam <slongerbeam@gmail.com> - 2017-05-29 20:20 +0200
        Re: [PATCH v7 00/34] i.MX Media Driver Pavel Machek <pavel@ucw.cz> - 2017-05-31 22:20 +0200
    Re: [PATCH v7 00/34] i.MX Media Driver Hans Verkuil <hverkuil@xs4all.nl> - 2017-05-29 19:30 +0200
    Re: [PATCH v7 00/34] i.MX Media Driver Steve Longerbeam <slongerbeam@gmail.com> - 2017-05-29 19:30 +0200
  Re: [PATCH v7 16/34] [media] add Omnivision OV5640 sensor driver Steve Longerbeam <slongerbeam@gmail.com> - 2017-05-30 00:00 +0200
    Re: [PATCH v7 16/34] [media] add Omnivision OV5640 sensor driver Sakari Ailus <sakari.ailus@iki.fi> - 2017-05-30 09:00 +0200
      Re: [PATCH v7 16/34] [media] add Omnivision OV5640 sensor driver Steve Longerbeam <slongerbeam@gmail.com> - 2017-06-03 20:10 +0200
        Re: [PATCH v7 16/34] [media] add Omnivision OV5640 sensor driver Steve Longerbeam <slongerbeam@gmail.com> - 2017-06-04 20:10 +0200
          Re: [PATCH v7 16/34] [media] add Omnivision OV5640 sensor driver Sakari Ailus <sakari.ailus@iki.fi> - 2017-06-07 14:40 +0200
  Re: [PATCH v7 16/34] [media] add Omnivision OV5640 sensor driver Pavel Machek <pavel@ucw.cz> - 2017-05-31 22:00 +0200
    Re: [PATCH v7 16/34] [media] add Omnivision OV5640 sensor driver Sakari Ailus <sakari.ailus@iki.fi> - 2017-06-01 10:30 +0200
      exposure vs. exposure_absolute was Re: [PATCH v7 16/34] [media] add  Omnivision OV5640 sensor driver Pavel Machek <pavel@ucw.cz> - 2017-06-01 10:50 +0200
      Re: [PATCH v7 16/34] [media] add Omnivision OV5640 sensor driver Steve Longerbeam <slongerbeam@gmail.com> - 2017-06-03 21:40 +0200
        Re: [PATCH v7 16/34] [media] add Omnivision OV5640 sensor driver Pavel Machek <pavel@ucw.cz> - 2017-06-03 22:00 +0200
          Re: [PATCH v7 16/34] [media] add Omnivision OV5640 sensor driver Sakari Ailus <sakari.ailus@iki.fi> - 2017-06-04 00:00 +0200
            Re: [PATCH v7 16/34] [media] add Omnivision OV5640 sensor driver Pavel Machek <pavel@ucw.cz> - 2017-06-04 00:20 +0200
            Re: [PATCH v7 16/34] [media] add Omnivision OV5640 sensor driver Steve Longerbeam <slongerbeam@gmail.com> - 2017-06-04 06:50 +0200
              Re: [PATCH v7 16/34] [media] add Omnivision OV5640 sensor driver Sakari Ailus <sakari.ailus@iki.fi> - 2017-06-07 14:40 +0200
  Re: [PATCH v7 00/34] i.MX Media Driver Tim Harvey <tharvey@gateworks.com> - 2017-06-02 02:30 +0200
    Re: [PATCH v7 00/34] i.MX Media Driver Steve Longerbeam <slongerbeam@gmail.com> - 2017-06-02 02:50 +0200

csiph-web