linux-api.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Arnd Bergmann <arnd@arndb.de>
To: y2038@lists.linaro.org
Cc: linux-samsung-soc@vger.kernel.org,
	Mauro Carvalho Chehab <mchehab@osg.samsung.com>,
	linux-api@vger.kernel.org, linux-kernel@vger.kernel.org,
	Hans Verkuil <hverkuil@xs4all.nl>,
	Laurent Pinchart <laurent.pinchart@ideasonboard.com>,
	linux-media@vger.kernel.org
Subject: Re: [PATCH v2 9/9] [media] omap3isp: support 64-bit version of omap3isp_stat_data
Date: Mon, 09 Nov 2015 21:30:41 +0100	[thread overview]
Message-ID: <3870339.ZAkvtJ2orM@wuerfel> (raw)
In-Reply-To: <5733951.qvCn4pc5g5@avalon>

On Monday 09 November 2015 22:09:26 Laurent Pinchart wrote:
> Hi Arnd,
> 
> Thank you for the patch.
> 
> On Thursday 17 September 2015 23:19:40 Arnd Bergmann wrote:
> > C libraries with 64-bit time_t use an incompatible format for
> > struct omap3isp_stat_data. This changes the kernel code to
> > support either version, by moving over the normal handling
> > to the 64-bit variant, and adding compatiblity code to handle
> > the old binary format with the existing ioctl command code.
> > 
> > Fortunately, the command code includes the size of the structure,
> > so the difference gets handled automatically.
> 
> We plan to design a new interface to handle statistics in V4L2. That API 
> should support proper 64-bit timestamps out of the box, and will be 
> implemented by the OMAP3 ISP driver. Userspace should then move to it. I 
> wonder if it's worth it to fix the existing VIDIOC_OMAP3ISP_STAT_REQ ioctl 
> given that I expect it to have a handful of users at most.

We still need to do something to the driver. The alternative would
be to make the existing ioctl command optional at kernel compile-time
so we can still build the driver once we remove the 'struct timeval'
definition. That patch would add slightly less complexity here
but also lose functionality.

As my patch here depends on the struct v4l2_timeval I introduced in
an earlier patch of the series, we will have to change it anyways,
but I'd prefer to keep the basic idea. Let's get back to this one
after the v4l_buffer replacement work is done.

	Arnd
_______________________________________________
Y2038 mailing list
Y2038@lists.linaro.org
https://lists.linaro.org/mailman/listinfo/y2038

  reply	other threads:[~2015-11-09 20:30 UTC|newest]

Thread overview: 24+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-09-17 21:19 [PATCH v2 0/9] [media] y2038 conversion for subsystem Arnd Bergmann
2015-09-17 21:19 ` [PATCH v2 1/9] [media] dvb: use ktime_t for internal timeout Arnd Bergmann
2015-09-17 21:19 ` [PATCH v2 2/9] [media] dvb: remove unused systime() function Arnd Bergmann
2015-09-17 21:19 ` [PATCH v2 3/9] [media] dvb: don't use 'time_t' in event ioctl Arnd Bergmann
2015-09-17 21:19 ` [PATCH v2 4/9] [media] exynos4-is: use monotonic timestamps as advertized Arnd Bergmann
2015-09-17 21:19 ` [PATCH v2 5/9] [media] make VIDIOC_DQEVENT work with 64-bit time_t Arnd Bergmann
2015-09-17 21:19 ` [PATCH v2 6/9] [media] use v4l2_get_timestamp where possible Arnd Bergmann
2015-09-17 21:19 ` [PATCH v2 7/9] [media] v4l2: introduce v4l2_timeval Arnd Bergmann
     [not found]   ` <1442524780-781677-8-git-send-email-arnd-r2nGTMty4D4@public.gmane.org>
2015-09-18  8:05     ` Hans Verkuil
2015-09-18  9:09       ` Arnd Bergmann
2015-09-18  9:27         ` Hans Verkuil
2015-09-18  9:43           ` Arnd Bergmann
2015-09-18  9:52             ` Hans Verkuil
2015-09-18 10:08               ` Arnd Bergmann
2015-09-18 10:22                 ` Hans Verkuil
     [not found] ` <1442524780-781677-1-git-send-email-arnd-r2nGTMty4D4@public.gmane.org>
2015-09-17 21:19   ` [PATCH v2 8/9] [media] handle 64-bit time_t in v4l2_buffer Arnd Bergmann
2015-09-18  7:18     ` Hans Verkuil
2015-09-18  9:26       ` Arnd Bergmann
2015-09-18  9:49         ` Hans Verkuil
2015-09-18 10:14           ` Arnd Bergmann
2015-09-17 21:19 ` [PATCH v2 9/9] [media] omap3isp: support 64-bit version of omap3isp_stat_data Arnd Bergmann
     [not found]   ` <1442524780-781677-10-git-send-email-arnd-r2nGTMty4D4@public.gmane.org>
2015-11-09 20:09     ` Laurent Pinchart
2015-11-09 20:30       ` Arnd Bergmann [this message]
2015-11-09 21:04         ` [Y2038] " Laurent Pinchart

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=3870339.ZAkvtJ2orM@wuerfel \
    --to=arnd@arndb.de \
    --cc=hverkuil@xs4all.nl \
    --cc=laurent.pinchart@ideasonboard.com \
    --cc=linux-api@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-media@vger.kernel.org \
    --cc=linux-samsung-soc@vger.kernel.org \
    --cc=mchehab@osg.samsung.com \
    --cc=y2038@lists.linaro.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).