linux-kernel - Re: [PATCH] media: v4l2-tpg: Remove unused tpg

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-ID: <aEDuaFSzA37QtuOf@gallifrey>
Date: Thu, 5 Jun 2025 01:10:00 +0000
From: "Dr. David Alan Gilbert" <linux@...blig.org>
To: Hans Verkuil <hans@...erkuil.nl>
Cc: mchehab@...nel.org, linux-media@...r.kernel.org,
	linux-kernel@...r.kernel.org
Subject: Re: [PATCH] media: v4l2-tpg: Remove unused tpg_fillbuffer

* Hans Verkuil (hans@...erkuil.nl) wrote:
> On 04/06/2025 00:51, linux@...blig.org wrote:
> > From: "Dr. David Alan Gilbert" <linux@...blig.org>
> > 
> > The last use of tpg_fillbuffer() was removed in 2015 by
> > commit ddcaee9dd4c0 ("[media] vivid: add support for single buffer planar
> > formats")
> > 
> > Remove it.
> 
> Ah, this can't be removed.
> 
> This tpg code is actually also used in git://linuxtv.org/v4l-utils.git which
> copies the code from the kernel source. And there this function is in use.

Ah OK, fair enough.

> This function is really a helper function. I think the best approach is to move
> this out of v4l2-tpg-core.c and into v4l2-tpg.h as a static inline.
> 
> That way it doesn't add to the kernel code size, but is still available when needed.

It feels a bit bug for a static inline to me; personally I wouldn't worry that much about
kernel size in that case - the tpg is in a separate module isn't it, which I guess
is rarely used in normal use?

> Perhaps add a comment in front of this function noting that it is used in v4l-utils.

Yeh, reasonable,

Thanks for the review,

Dave

> Regards,
> 
> 	Hans
> 
> > 
> > Signed-off-by: Dr. David Alan Gilbert <linux@...blig.org>
> > ---
> >  drivers/media/common/v4l2-tpg/v4l2-tpg-core.c | 17 -----------------
> >  include/media/tpg/v4l2-tpg.h                  |  2 --
> >  2 files changed, 19 deletions(-)
> > 
> > diff --git a/drivers/media/common/v4l2-tpg/v4l2-tpg-core.c b/drivers/media/common/v4l2-tpg/v4l2-tpg-core.c
> > index 931e5dc453b9..d51d8ba99dcb 100644
> > --- a/drivers/media/common/v4l2-tpg/v4l2-tpg-core.c
> > +++ b/drivers/media/common/v4l2-tpg/v4l2-tpg-core.c
> > @@ -2710,23 +2710,6 @@ void tpg_fill_plane_buffer(struct tpg_data *tpg, v4l2_std_id std,
> >  }
> >  EXPORT_SYMBOL_GPL(tpg_fill_plane_buffer);
> >  
> > -void tpg_fillbuffer(struct tpg_data *tpg, v4l2_std_id std, unsigned p, u8 *vbuf)
> > -{
> > -	unsigned offset = 0;
> > -	unsigned i;
> > -
> > -	if (tpg->buffers > 1) {
> > -		tpg_fill_plane_buffer(tpg, std, p, vbuf);
> > -		return;
> > -	}
> > -
> > -	for (i = 0; i < tpg_g_planes(tpg); i++) {
> > -		tpg_fill_plane_buffer(tpg, std, i, vbuf + offset);
> > -		offset += tpg_calc_plane_size(tpg, i);
> > -	}
> > -}
> > -EXPORT_SYMBOL_GPL(tpg_fillbuffer);
> > -
> >  MODULE_DESCRIPTION("V4L2 Test Pattern Generator");
> >  MODULE_AUTHOR("Hans Verkuil");
> >  MODULE_LICENSE("GPL");
> > diff --git a/include/media/tpg/v4l2-tpg.h b/include/media/tpg/v4l2-tpg.h
> > index a55088921d1d..3e3bd0889b6d 100644
> > --- a/include/media/tpg/v4l2-tpg.h
> > +++ b/include/media/tpg/v4l2-tpg.h
> > @@ -248,8 +248,6 @@ void tpg_calc_text_basep(struct tpg_data *tpg,
> >  unsigned tpg_g_interleaved_plane(const struct tpg_data *tpg, unsigned buf_line);
> >  void tpg_fill_plane_buffer(struct tpg_data *tpg, v4l2_std_id std,
> >  			   unsigned p, u8 *vbuf);
> > -void tpg_fillbuffer(struct tpg_data *tpg, v4l2_std_id std,
> > -		    unsigned p, u8 *vbuf);
> >  bool tpg_s_fourcc(struct tpg_data *tpg, u32 fourcc);
> >  void tpg_s_crop_compose(struct tpg_data *tpg, const struct v4l2_rect *crop,
> >  		const struct v4l2_rect *compose);
> 
> 
-- 
 -----Open up your eyes, open up your mind, open up your code -------   
/ Dr. David Alan Gilbert    |       Running GNU/Linux       | Happy  \ 
\        dave @ treblig.org |                               | In Hex /
 \ _________________________|_____ http://www.treblig.org   |_______/