Re: [PATCH 0/6] media: v4l2-isp: Add support for extensible statistics

[Jacopo Mondi]

Hi Antoine, Keke

On Wed, May 13, 2026 at 09:04:27AM +0800, Keke Li wrote:
>
> On 5/12/26 17:26, Antoine Bouyer wrote:
> > [ EXTERNAL EMAIL ]
> >
> > Le 05/05/2026 à 18:49, Antoine Bouyer a écrit :
> > > On 5/5/26 4:12 PM, Jacopo Mondi wrote:
> > > >
> > > >
> > > > This series breaks out from Antonie's
> > > > https://eur01.safelinks.protection.outlook.com/?
> > > > url=https%3A%2F%2Fpatchwork.linuxtv.org%2Fproject%2Flinux-
> > > > media%2Flist%2F%3Fseries%3D24043&data=05%7C02%7Cantoine.bouyer%40nxp.com%7Cd0e9f403856c4146996308deaab05cd1%7C686ea1d3bc2b4c6fa92cd99c5c301635%7C0%7C0%7C639135871605732002%7CUnknown%7CTWFpbGZsb3d8eyJFbXB0eU1hcGkiOnRydWUsIlYiOiIwLjAuMDAwMCIsIlAiOiJXaW4zMiIsIkFOIjoiTWFpbCIsIldUIjoyfQ%3D%3D%7C0%7C%7C%7C&sdata=FXaz7QYQvS3s%2B4l9AFMrGgE7kmXlEil%2FKD6DibB0%2FJY%3D&reserved=0
> > > >
> > > > the extensible stats support and adds a few more patches on top to:
> > > >
> > > > - add support for per-block validation as suggested during the
> > > > review of
> > > >    Ricardo's
> > > >    https://eur01.safelinks.protection.outlook.com/?
> > > > url=https%3A%2F%2Fpatchwork.linuxtv.org%2Fproject%2Flinux-
> > > > media%2Fpatch%2F20260504-smatch-7-1-v3-6-
> > > > fda125c30058%40chromium.org%2F&data=05%7C02%7Cantoine.bouyer%40nxp.com%7Cd0e9f403856c4146996308deaab05cd1%7C686ea1d3bc2b4c6fa92cd99c5c301635%7C0%7C0%7C639135871605751612%7CUnknown%7CTWFpbGZsb3d8eyJFbXB0eU1hcGkiOnRydWUsIlYiOiIwLjAuMDAwMCIsIlAiOiJXaW4zMiIsIkFOIjoiTWFpbCIsIldUIjoyfQ%3D%3D%7C0%7C%7C%7C&sdata=AiRH8MhIbXt3dr%2B2r3I6STE6TJAChylnH%2Fz3tLdS36k%3D&reserved=0
> > > >
> > > >
> > > > - add two helper functions to v4l2-isp to ease handling of extensible
> > > >    statistics for drivers. An early user, based on a preliminary
> > > > version
> > > >    of the patches is available here as a reference:
> > > >    https://eur01.safelinks.protection.outlook.com/?
> > > > url=https%3A%2F%2Fpatchwork.linuxtv.org%2Fproject%2Flinux-
> > > > media%2Flist%2F%3Fseries%3D24703&data=05%7C02%7Cantoine.bouyer%40nxp.com%7Cd0e9f403856c4146996308deaab05cd1%7C686ea1d3bc2b4c6fa92cd99c5c301635%7C0%7C0%7C639135871605763086%7CUnknown%7CTWFpbGZsb3d8eyJFbXB0eU1hcGkiOnRydWUsIlYiOiIwLjAuMDAwMCIsIlAiOiJXaW4zMiIsIkFOIjoiTWFpbCIsIldUIjoyfQ%3D%3D%7C0%7C%7C%7C&sdata=%2Fpsb7Z3lb8ingDILxc3LoEWKTojl5BGMbk6FiR%2FcO9I%3D&reserved=0
> > > >
> > > >
> > > > Antonie: I took the liberty to fold in your patches changes to address
> > > > my comments on your v1. I pushed an un-squased version of the patches
> > > > here:
> > > > https://eur01.safelinks.protection.outlook.com/?
> > > > url=https%3A%2F%2Fgitlab.freedesktop.org%2Flinux-
> > > > media%2Fusers%2Fjmondi%2F-%2Ftree%2Fb4%2Fextensible-stats-
> > > > unsquashed&data=05%7C02%7Cantoine.bouyer%40nxp.com%7Cd0e9f403856c4146996308deaab05cd1%7C686ea1d3bc2b4c6fa92cd99c5c301635%7C0%7C0%7C639135871605775020%7CUnknown%7CTWFpbGZsb3d8eyJFbXB0eU1hcGkiOnRydWUsIlYiOiIwLjAuMDAwMCIsIlAiOiJXaW4zMiIsIkFOIjoiTWFpbCIsIldUIjoyfQ%3D%3D%7C0%7C%7C%7C&sdata=iF2BE0GZ8HcVPmOJDhbmLsXQDOXV9JvqfMK6DRPPvrg%3D&reserved=0
> > > >
> > > > so you can easily get the diff from this and your version. Please feel
> > > > free to comment on these as you're the original author.
> > >
> > > Hi Jacopo
> > >
> > > Thanks for the rework and the links. I'm fine with your [SQUASH]
> > > commits.
> > >
> > > If there are no other comments, I assume I can reuse the common patches
> > > in my v2 then, and also apply the new helpers to neoisp driver changes.
> > > They look very useful (especially to prevent out-of-bounds crashes I
> > > observed when data_size was not set before filling stats :( ). I'll
> > > check in your user example.
> > >
> > > BR
> > > Antoine
> >
> > Hi Jacopo
> >
> > Do you think it would make sense to create a new generic V4L2_META_FMT
> > too ? which can be used by all user of v4l2-isp extensible params a/o
> > stats. To avoid each driver creating its own meta fmt with same purpose.
> >
> > Or do you think it could have side effects ?
> >
> > BR
> > Antoine
> >
> > >
> I think this proposal is excellent.
> 🙂

To me, platform-specific formats mostly serve for documenting the ISP blocks.
In example
https://www.kernel.org/doc/html/latest/userspace-api/media/v4l/metafmt-rkisp1.html

There might be ways to handle it without defining a dedicated format
indeed.

Sakari Laurent and Hans are in cc, what do they think ?



> > > >
> > > > Signed-off-by: Jacopo Mondi <jacopo.mondi@xxxxxxxxxxxxxxxx>
> > > > ---
> > > > Antoine Bouyer (2):
> > > >        media: uapi: v4l2-isp: Add extensible statistics
> > > >        media: Documentation: uapi: Update V4L2 ISP for extensible stats
> > > >
> > > > Jacopo Mondi (4):
> > > >        media: v4l2-isp: Rename v4l2_isp_params_buffer_size
> > > >        media: v4l2-isp: Add per-block validation callback
> > > >        media: amlogic-c3: Implement per-block validation
> > > >        media: v4l2-isp: Add helpers for stats buffer
> > > >
> > > >   Documentation/userspace-api/media/v4l/v4l2-isp.rst |  45 ++++++--
> > > >   .../media/platform/amlogic/c3/isp/c3-isp-params.c  |  42 ++++++-
> > > >   .../media/platform/arm/mali-c55/mali-c55-params.c  |  12 +-
> > > >   drivers/media/v4l2-core/v4l2-isp.c                 |  56 +++++++++
> > > >   include/media/v4l2-isp.h                           |  94 +++++++++++
> > > > ++---
> > > >   include/uapi/linux/media/v4l2-isp.h                | 125 +++++++++++
> > > > ++--------
> > > >   6 files changed, 294 insertions(+), 80 deletions(-)
> > > > ---
> > > > base-commit: d9c8c4adf23d17549c0ec9c85b99d85a0ee6cf18
> > > > change-id: 20260504-extensible-stats-f2d6befcc1ce
> > > >
> > > > Best regards,
> > > > --
> > > > Jacopo Mondi <jacopo.mondi@xxxxxxxxxxxxxxxx>
> > > >
> > >
> >
>