From: Hans de Goede <hdegoede@redhat.com>
To: Hans Verkuil <hverkuil@xs4all.nl>
Cc: Hans Verkuil <hansverk@cisco.com>,
Linux Media Mailing List <linux-media@vger.kernel.org>
Subject: Re: Some comments on the new autocluster patches
Date: Tue, 26 Jul 2011 16:38:19 +0200 [thread overview]
Message-ID: <4E2ED15B.6070601@redhat.com> (raw)
In-Reply-To: <201107261619.47827.hverkuil@xs4all.nl>
Hi,
On 07/26/2011 04:19 PM, Hans Verkuil wrote:
> On Tuesday, July 26, 2011 15:51:58 Hans de Goede wrote:
>
<snip>
>>> An open question is whether writing to an inactive and volatile control should return
>>> an error or not.
>>
>> I would prefer an error return.
>
> I am worried about backwards compatibility, though. Right now inactive controls
> can be written safely. Suddenly you add the volatile flag and doing the same thing
> causes an error.
>
> Also, a program that saves control values will have to skip any control that:
>
> 1) Is read or write only
> 2) Is inactive and volatile
>
> The first is obvious, but the second not so much.
>
> Another reason for not returning an error is that it makes v4l2-ctrls.c more complex: if
> autogain is on and I call VIDIOC_S_EXT_CTRLS to set autogain to off and gain to a new
> manual value, then it is quite difficult to detect that in this case setting gain is OK
> (since autogain is turned off at the same time).
>
> The more I think about it, the more I think this should just be allowed. The value
> disappears into a black hole, but at least it won't break any apps.
Ok disappear into a black hole it is :)
Regards,
Hans
next prev parent reply other threads:[~2011-07-26 14:36 UTC|newest]
Thread overview: 15+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-07-01 15:06 Some comments on the new autocluster patches Hans de Goede
2011-07-01 16:21 ` Hans Verkuil
2011-07-02 10:28 ` Hans de Goede
2011-07-02 11:10 ` Hans Verkuil
2011-07-02 14:31 ` Hans de Goede
2011-07-04 9:43 ` Hans Verkuil
2011-07-12 13:25 ` Hans de Goede
2011-07-26 9:26 ` Hans Verkuil
2011-07-26 13:51 ` Hans de Goede
2011-07-26 14:19 ` Hans Verkuil
2011-07-26 14:38 ` Hans de Goede [this message]
2011-07-26 14:39 ` Hans Verkuil
2011-07-02 0:55 ` Mauro Carvalho Chehab
2011-07-02 9:36 ` Hans Verkuil
2011-07-02 18:33 ` Mauro Carvalho Chehab
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=4E2ED15B.6070601@redhat.com \
--to=hdegoede@redhat.com \
--cc=hansverk@cisco.com \
--cc=hverkuil@xs4all.nl \
--cc=linux-media@vger.kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).