[PATCH 00/25] media: v4l2-mem2mem: Reduce cargo-cult

[PATCH 00/25] media: v4l2-mem2mem: Reduce cargo-cult

[Laurent Pinchart]

Hello,

The v4l2_m2m_get_vq() function never returns NULL, but many mem2mem
drivers still check its return value and consider NULL as an error. This
may have originated a long time ago from valid checks when
v4l2_m2m_get_vq() could return NULL, with drivers then just copying the
checks. This series attempts to stop the cargo-cult behaviour.

Patch 01/25 starts by explicitly stating in kerneldoc that the
v4l2_m2m_get_vq() function never returns NULL. All the other patches
drop NULL checks from drivers.

I have carefully checked all patched locations in all drivers. They fall
in 3 categories:

- Checks in the VIDIOC_G_FMT, VIDIOC_TRY_FMT and VIDIOC_S_FMT handlers:
  Those may have been added to ensure that the format type has a valid
  value, but that is ensured by the V4L2 ioctl core before calling the
  handlers. The checks can be dropped without a need to replace them
  with proper type checks.

- Checks in the VIDIOC_S_SELECTION handler: The only location where this
  is performed has an explicit type check, so the NULL check can also be
  dropped.

- Checks in other locations where the type parameter to the
  v4l2_m2m_get_vq() function is hardcoded: The hardcoded type is valid,
  so the NULL check can't have been meant to check the type. It can also
  be removed.

There's no dependency between any of those patches so they can be merged
in any order.

Laurent Pinchart (25):
  media: v4l2-mem2mem: Document that v4l2_m2m_get_vq() never returns
    NULL
  media: allgro-dvt: Drop unneeded v4l2_m2m_get_vq() NULL check
  media: meson-g2d: Drop unneeded v4l2_m2m_get_vq() NULL check
  media: amphion: Drop unneeded v4l2_m2m_get_vq() NULL check
  media: coda: Drop unneeded v4l2_m2m_get_vq() NULL check
  media: imagination: e5010: Drop unneeded v4l2_m2m_get_vq() NULL check
  media: m2m-deinterlace: Drop unneeded v4l2_m2m_get_vq() NULL check
  media: mediatek: jpeg: Drop unneeded v4l2_m2m_get_vq() NULL check
  media: mediatek: vcodec: Drop unneeded v4l2_m2m_get_vq() NULL check
  media: dw100: Drop unneeded v4l2_m2m_get_vq() NULL check
  media: imx-jpeg: Drop unneeded v4l2_m2m_get_vq() NULL check
  media: imx-pxp: Drop unneeded v4l2_m2m_get_vq() NULL check
  media: nxp: imx8-isi: Drop unneeded v4l2_m2m_get_vq() NULL check
  media: mx2_emmaprp: Drop unneeded v4l2_m2m_get_vq() NULL check
  media: qcom: iris: Drop unneeded v4l2_m2m_get_vq() NULL check
  media: qcom: venus: Drop unneeded v4l2_m2m_get_vq() NULL check
  media: renesas: fdp1: Drop unneeded v4l2_m2m_get_vq() NULL check
  media: rcar_jpu: Drop unneeded v4l2_m2m_get_vq() NULL check
  media: platform: rga: Drop unneeded v4l2_m2m_get_vq() NULL check
  media: samsung: s5p-g2d: Drop unneeded v4l2_m2m_get_vq() NULL check
  media: samsung: s5p-jpeg: Drop unneeded v4l2_m2m_get_vq() NULL check
  media: stm32: dma2d: Drop unneeded v4l2_m2m_get_vq() NULL check
  media: ti: vpe: Drop unneeded v4l2_m2m_get_vq() NULL check
  media: vicodec: Drop unneeded v4l2_m2m_get_vq() NULL check
  media: vim2m: Drop unneeded v4l2_m2m_get_vq() NULL check

 drivers/media/platform/allegro-dvt/allegro-core.c    |  2 --
 drivers/media/platform/amlogic/meson-ge2d/ge2d.c     |  5 -----
 drivers/media/platform/amphion/vdec.c                |  2 --
 drivers/media/platform/amphion/venc.c                |  2 --
 .../media/platform/chips-media/coda/coda-common.c    |  4 ----
 drivers/media/platform/imagination/e5010-jpeg-enc.c  |  4 ----
 drivers/media/platform/m2m-deinterlace.c             |  7 -------
 drivers/media/platform/mediatek/jpeg/mtk_jpeg_core.c |  7 -------
 .../mediatek/vcodec/decoder/mtk_vcodec_dec.c         |  7 -------
 .../vcodec/decoder/vdec/vdec_av1_req_lat_if.c        |  2 --
 .../vcodec/decoder/vdec/vdec_vp9_req_lat_if.c        |  2 --
 .../mediatek/vcodec/encoder/mtk_vcodec_enc.c         |  8 --------
 drivers/media/platform/nxp/dw100/dw100.c             |  7 -------
 drivers/media/platform/nxp/imx-jpeg/mxc-jpeg.c       |  4 ----
 drivers/media/platform/nxp/imx-pxp.c                 |  7 -------
 drivers/media/platform/nxp/imx8-isi/imx8-isi-m2m.c   |  2 --
 drivers/media/platform/nxp/mx2_emmaprp.c             |  7 -------
 drivers/media/platform/qcom/iris/iris_vdec.c         |  2 --
 drivers/media/platform/qcom/venus/vdec.c             |  2 --
 drivers/media/platform/qcom/venus/venc.c             |  2 --
 drivers/media/platform/renesas/rcar_fdp1.c           |  3 ---
 drivers/media/platform/renesas/rcar_jpu.c            |  8 --------
 drivers/media/platform/rockchip/rga/rga.c            |  4 ----
 drivers/media/platform/samsung/s5p-g2d/g2d.c         |  4 ----
 drivers/media/platform/samsung/s5p-jpeg/jpeg-core.c  |  7 -------
 drivers/media/platform/st/stm32/dma2d/dma2d.c        |  5 -----
 drivers/media/platform/ti/vpe/vpe.c                  |  7 -------
 drivers/media/test-drivers/vicodec/vicodec-core.c    |  7 -------
 drivers/media/test-drivers/vim2m.c                   | 12 ------------
 drivers/media/v4l2-core/v4l2-mem2mem.c               | 12 +-----------
 include/media/v4l2-mem2mem.h                         |  3 +++
 31 files changed, 4 insertions(+), 153 deletions(-)


base-commit: e5f0a698b34ed76002dc5cff3804a61c80233a7a
-- 
Regards,

Laurent Pinchart

[PATCH 11/25] media: imx-jpeg: Drop unneeded v4l2_m2m_get_vq() NULL check

[Laurent Pinchart]

The v4l2_m2m_get_vq() function never returns NULL. The check may have
been intended to catch invalid format types, but that's not needed as
the V4L2 core picks the appropriate VIDIOC_S_FMT ioctl handler based on
the format type, so the type can't be incorrect. Drop the unneeded
return value check.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
---
 drivers/media/platform/nxp/imx-jpeg/mxc-jpeg.c | 4 ----
 1 file changed, 4 deletions(-)

diff --git a/drivers/media/platform/nxp/imx-jpeg/mxc-jpeg.c b/drivers/media/platform/nxp/imx-jpeg/mxc-jpeg.c
index 8681dd193033..37e0670f98c5 100644
--- a/drivers/media/platform/nxp/imx-jpeg/mxc-jpeg.c
+++ b/drivers/media/platform/nxp/imx-jpeg/mxc-jpeg.c
@@ -2492,8 +2492,6 @@ static int mxc_jpeg_s_fmt(struct mxc_jpeg_ctx *ctx,
 	struct mxc_jpeg_dev *jpeg = ctx->mxc_jpeg;
 
 	vq = v4l2_m2m_get_vq(ctx->fh.m2m_ctx, f->type);
-	if (!vq)
-		return -EINVAL;
 
 	if (vb2_is_busy(vq)) {
 		v4l2_err(&jpeg->v4l2_dev, "queue busy\n");
@@ -2529,8 +2527,6 @@ static int mxc_jpeg_s_fmt_vid_out(struct file *file, void *priv,
 		return 0;
 
 	dst_vq = v4l2_m2m_get_vq(ctx->fh.m2m_ctx, cap_type);
-	if (!dst_vq)
-		return -EINVAL;
 
 	if (vb2_is_busy(dst_vq))
 		return 0;
-- 
Regards,

Laurent Pinchart

[PATCH 12/25] media: imx-pxp: Drop unneeded v4l2_m2m_get_vq() NULL check

[Laurent Pinchart]

The v4l2_m2m_get_vq() function never returns NULL.

In the set format handler, the check may have been intended to catch
invalid format types, but that's not needed as the V4L2 core picks the
appropriate VIDIOC_S_FMT ioctl handler based on the format type, so the
type can't be incorrect.

In the get format handler, the return value is not used for any purpose
other than the NULL check, which was therefore probably intended to
catch invalid format types. That's not needed for the same reason as in
the set format handler.

Drop the unneeded return value checks and, as the function has no side
effect, the unneeded function call as well.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
---
 drivers/media/platform/nxp/imx-pxp.c | 7 -------
 1 file changed, 7 deletions(-)

diff --git a/drivers/media/platform/nxp/imx-pxp.c b/drivers/media/platform/nxp/imx-pxp.c
index 7f8ffbac582f..5386650ce194 100644
--- a/drivers/media/platform/nxp/imx-pxp.c
+++ b/drivers/media/platform/nxp/imx-pxp.c
@@ -1180,13 +1180,8 @@ static int pxp_enum_fmt_vid_out(struct file *file, void *priv,
 
 static int pxp_g_fmt(struct pxp_ctx *ctx, struct v4l2_format *f)
 {
-	struct vb2_queue *vq;
 	struct pxp_q_data *q_data;
 
-	vq = v4l2_m2m_get_vq(ctx->fh.m2m_ctx, f->type);
-	if (!vq)
-		return -EINVAL;
-
 	q_data = get_q_data(ctx, f->type);
 
 	f->fmt.pix.width	= q_data->width;
@@ -1329,8 +1324,6 @@ static int pxp_s_fmt(struct pxp_ctx *ctx, struct v4l2_format *f)
 	struct vb2_queue *vq;
 
 	vq = v4l2_m2m_get_vq(ctx->fh.m2m_ctx, f->type);
-	if (!vq)
-		return -EINVAL;
 
 	q_data = get_q_data(ctx, f->type);
 	if (!q_data)
-- 
Regards,

Laurent Pinchart

[PATCH 13/25] media: nxp: imx8-isi: Drop unneeded v4l2_m2m_get_vq() NULL check

[Laurent Pinchart]

The v4l2_m2m_get_vq() function never returns NULL. The check may have
been intended to catch invalid format types, but that's not needed as
the V4L2 core picks the appropriate VIDIOC_S_FMT ioctl handler based on
the format type, so the type can't be incorrect. Drop the unneeded
return value check.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
---
 drivers/media/platform/nxp/imx8-isi/imx8-isi-m2m.c | 2 --
 1 file changed, 2 deletions(-)

diff --git a/drivers/media/platform/nxp/imx8-isi/imx8-isi-m2m.c b/drivers/media/platform/nxp/imx8-isi/imx8-isi-m2m.c
index 6822c2f7fc69..675f1d2b65d9 100644
--- a/drivers/media/platform/nxp/imx8-isi/imx8-isi-m2m.c
+++ b/drivers/media/platform/nxp/imx8-isi/imx8-isi-m2m.c
@@ -554,8 +554,6 @@ static int mxc_isi_m2m_s_fmt_vid(struct file *file, void *fh,
 	struct vb2_queue *vq;
 
 	vq = v4l2_m2m_get_vq(ctx->fh.m2m_ctx, f->type);
-	if (!vq)
-		return -EINVAL;
 
 	if (vb2_is_busy(vq))
 		return -EBUSY;
-- 
Regards,

Laurent Pinchart

Re: [PATCH 00/25] media: v4l2-mem2mem: Reduce cargo-cult

[Nicolas Dufresne]

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Hi,

Le mercredi 08 octobre 2025 à 20:50 +0300, Laurent Pinchart a écrit :
> Hello,
> 
> The v4l2_m2m_get_vq() function never returns NULL, but many mem2mem
> drivers still check its return value and consider NULL as an error. This
> may have originated a long time ago from valid checks when
> v4l2_m2m_get_vq() could return NULL, with drivers then just copying the
> checks. This series attempts to stop the cargo-cult behaviour.
> 
> Patch 01/25 starts by explicitly stating in kerneldoc that the
> v4l2_m2m_get_vq() function never returns NULL. All the other patches
> drop NULL checks from drivers.
> 
> I have carefully checked all patched locations in all drivers. They fall
> in 3 categories:
> 
> - Checks in the VIDIOC_G_FMT, VIDIOC_TRY_FMT and VIDIOC_S_FMT handlers:
>   Those may have been added to ensure that the format type has a valid
>   value, but that is ensured by the V4L2 ioctl core before calling the
>   handlers. The checks can be dropped without a need to replace them
>   with proper type checks.
> 
> - Checks in the VIDIOC_S_SELECTION handler: The only location where this
>   is performed has an explicit type check, so the NULL check can also be
>   dropped.
> 
> - Checks in other locations where the type parameter to the
>   v4l2_m2m_get_vq() function is hardcoded: The hardcoded type is valid,
>   so the NULL check can't have been meant to check the type. It can also
>   be removed.
> 
> There's no dependency between any of those patches so they can be merged
> in any order.
> 
> Laurent Pinchart (25):
>   media: v4l2-mem2mem: Document that v4l2_m2m_get_vq() never returns
>     NULL
>   media: allgro-dvt: Drop unneeded v4l2_m2m_get_vq() NULL check
>   media: meson-g2d: Drop unneeded v4l2_m2m_get_vq() NULL check
>   media: amphion: Drop unneeded v4l2_m2m_get_vq() NULL check
>   media: coda: Drop unneeded v4l2_m2m_get_vq() NULL check
>   media: imagination: e5010: Drop unneeded v4l2_m2m_get_vq() NULL check
>   media: m2m-deinterlace: Drop unneeded v4l2_m2m_get_vq() NULL check
>   media: mediatek: jpeg: Drop unneeded v4l2_m2m_get_vq() NULL check
>   media: mediatek: vcodec: Drop unneeded v4l2_m2m_get_vq() NULL check
>   media: dw100: Drop unneeded v4l2_m2m_get_vq() NULL check
>   media: imx-jpeg: Drop unneeded v4l2_m2m_get_vq() NULL check
>   media: imx-pxp: Drop unneeded v4l2_m2m_get_vq() NULL check
>   media: nxp: imx8-isi: Drop unneeded v4l2_m2m_get_vq() NULL check
>   media: mx2_emmaprp: Drop unneeded v4l2_m2m_get_vq() NULL check
>   media: qcom: iris: Drop unneeded v4l2_m2m_get_vq() NULL check
>   media: qcom: venus: Drop unneeded v4l2_m2m_get_vq() NULL check
>   media: renesas: fdp1: Drop unneeded v4l2_m2m_get_vq() NULL check
>   media: rcar_jpu: Drop unneeded v4l2_m2m_get_vq() NULL check

Why not "renesas: jpu" to match the fdp1 patch naming ?

>   media: platform: rga: Drop unneeded v4l2_m2m_get_vq() NULL check
>   media: samsung: s5p-g2d: Drop unneeded v4l2_m2m_get_vq() NULL check
>   media: samsung: s5p-jpeg: Drop unneeded v4l2_m2m_get_vq() NULL check
>   media: stm32: dma2d: Drop unneeded v4l2_m2m_get_vq() NULL check
>   media: ti: vpe: Drop unneeded v4l2_m2m_get_vq() NULL check
>   media: vicodec: Drop unneeded v4l2_m2m_get_vq() NULL check
>   media: vim2m: Drop unneeded v4l2_m2m_get_vq() NULL check

I reviewed the list and it seems complete to me.

Nicolas

> 
>  drivers/media/platform/allegro-dvt/allegro-core.c    |  2 --
>  drivers/media/platform/amlogic/meson-ge2d/ge2d.c     |  5 -----
>  drivers/media/platform/amphion/vdec.c                |  2 --
>  drivers/media/platform/amphion/venc.c                |  2 --
>  .../media/platform/chips-media/coda/coda-common.c    |  4 ----
>  drivers/media/platform/imagination/e5010-jpeg-enc.c  |  4 ----
>  drivers/media/platform/m2m-deinterlace.c             |  7 -------
>  drivers/media/platform/mediatek/jpeg/mtk_jpeg_core.c |  7 -------
>  .../mediatek/vcodec/decoder/mtk_vcodec_dec.c         |  7 -------
>  .../vcodec/decoder/vdec/vdec_av1_req_lat_if.c        |  2 --
>  .../vcodec/decoder/vdec/vdec_vp9_req_lat_if.c        |  2 --
>  .../mediatek/vcodec/encoder/mtk_vcodec_enc.c         |  8 --------
>  drivers/media/platform/nxp/dw100/dw100.c             |  7 -------
>  drivers/media/platform/nxp/imx-jpeg/mxc-jpeg.c       |  4 ----
>  drivers/media/platform/nxp/imx-pxp.c                 |  7 -------
>  drivers/media/platform/nxp/imx8-isi/imx8-isi-m2m.c   |  2 --
>  drivers/media/platform/nxp/mx2_emmaprp.c             |  7 -------
>  drivers/media/platform/qcom/iris/iris_vdec.c         |  2 --
>  drivers/media/platform/qcom/venus/vdec.c             |  2 --
>  drivers/media/platform/qcom/venus/venc.c             |  2 --
>  drivers/media/platform/renesas/rcar_fdp1.c           |  3 ---
>  drivers/media/platform/renesas/rcar_jpu.c            |  8 --------
>  drivers/media/platform/rockchip/rga/rga.c            |  4 ----
>  drivers/media/platform/samsung/s5p-g2d/g2d.c         |  4 ----
>  drivers/media/platform/samsung/s5p-jpeg/jpeg-core.c  |  7 -------
>  drivers/media/platform/st/stm32/dma2d/dma2d.c        |  5 -----
>  drivers/media/platform/ti/vpe/vpe.c                  |  7 -------
>  drivers/media/test-drivers/vicodec/vicodec-core.c    |  7 -------
>  drivers/media/test-drivers/vim2m.c                   | 12 ------------
>  drivers/media/v4l2-core/v4l2-mem2mem.c               | 12 +-----------
>  include/media/v4l2-mem2mem.h                         |  3 +++
>  31 files changed, 4 insertions(+), 153 deletions(-)
> 
> 
> base-commit: e5f0a698b34ed76002dc5cff3804a61c80233a7a

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Re: [PATCH 00/25] media: v4l2-mem2mem: Reduce cargo-cult

[Laurent Pinchart]

On Wed, Oct 08, 2025 at 02:24:30PM -0400, Nicolas Dufresne wrote:
> Hi,
> 
> Le mercredi 08 octobre 2025 à 20:50 +0300, Laurent Pinchart a écrit :
> > Hello,
> > 
> > The v4l2_m2m_get_vq() function never returns NULL, but many mem2mem
> > drivers still check its return value and consider NULL as an error. This
> > may have originated a long time ago from valid checks when
> > v4l2_m2m_get_vq() could return NULL, with drivers then just copying the
> > checks. This series attempts to stop the cargo-cult behaviour.
> > 
> > Patch 01/25 starts by explicitly stating in kerneldoc that the
> > v4l2_m2m_get_vq() function never returns NULL. All the other patches
> > drop NULL checks from drivers.
> > 
> > I have carefully checked all patched locations in all drivers. They fall
> > in 3 categories:
> > 
> > - Checks in the VIDIOC_G_FMT, VIDIOC_TRY_FMT and VIDIOC_S_FMT handlers:
> >   Those may have been added to ensure that the format type has a valid
> >   value, but that is ensured by the V4L2 ioctl core before calling the
> >   handlers. The checks can be dropped without a need to replace them
> >   with proper type checks.
> > 
> > - Checks in the VIDIOC_S_SELECTION handler: The only location where this
> >   is performed has an explicit type check, so the NULL check can also be
> >   dropped.
> > 
> > - Checks in other locations where the type parameter to the
> >   v4l2_m2m_get_vq() function is hardcoded: The hardcoded type is valid,
> >   so the NULL check can't have been meant to check the type. It can also
> >   be removed.
> > 
> > There's no dependency between any of those patches so they can be merged
> > in any order.
> > 
> > Laurent Pinchart (25):
> >   media: v4l2-mem2mem: Document that v4l2_m2m_get_vq() never returns
> >     NULL
> >   media: allgro-dvt: Drop unneeded v4l2_m2m_get_vq() NULL check
> >   media: meson-g2d: Drop unneeded v4l2_m2m_get_vq() NULL check
> >   media: amphion: Drop unneeded v4l2_m2m_get_vq() NULL check
> >   media: coda: Drop unneeded v4l2_m2m_get_vq() NULL check
> >   media: imagination: e5010: Drop unneeded v4l2_m2m_get_vq() NULL check
> >   media: m2m-deinterlace: Drop unneeded v4l2_m2m_get_vq() NULL check
> >   media: mediatek: jpeg: Drop unneeded v4l2_m2m_get_vq() NULL check
> >   media: mediatek: vcodec: Drop unneeded v4l2_m2m_get_vq() NULL check
> >   media: dw100: Drop unneeded v4l2_m2m_get_vq() NULL check
> >   media: imx-jpeg: Drop unneeded v4l2_m2m_get_vq() NULL check
> >   media: imx-pxp: Drop unneeded v4l2_m2m_get_vq() NULL check
> >   media: nxp: imx8-isi: Drop unneeded v4l2_m2m_get_vq() NULL check
> >   media: mx2_emmaprp: Drop unneeded v4l2_m2m_get_vq() NULL check
> >   media: qcom: iris: Drop unneeded v4l2_m2m_get_vq() NULL check
> >   media: qcom: venus: Drop unneeded v4l2_m2m_get_vq() NULL check
> >   media: renesas: fdp1: Drop unneeded v4l2_m2m_get_vq() NULL check
> >   media: rcar_jpu: Drop unneeded v4l2_m2m_get_vq() NULL check
> 
> Why not "renesas: jpu" to match the fdp1 patch naming ?

I tried to go with the most common prefix as reported by git log. I
don't mind changing this, I'll wait for more reviews to see if a v2 is
needed, otherwise this can be updated when applying if desired.

> >   media: platform: rga: Drop unneeded v4l2_m2m_get_vq() NULL check
> >   media: samsung: s5p-g2d: Drop unneeded v4l2_m2m_get_vq() NULL check
> >   media: samsung: s5p-jpeg: Drop unneeded v4l2_m2m_get_vq() NULL check
> >   media: stm32: dma2d: Drop unneeded v4l2_m2m_get_vq() NULL check
> >   media: ti: vpe: Drop unneeded v4l2_m2m_get_vq() NULL check
> >   media: vicodec: Drop unneeded v4l2_m2m_get_vq() NULL check
> >   media: vim2m: Drop unneeded v4l2_m2m_get_vq() NULL check
> 
> I reviewed the list and it seems complete to me.

Thank you.

> >  drivers/media/platform/allegro-dvt/allegro-core.c    |  2 --
> >  drivers/media/platform/amlogic/meson-ge2d/ge2d.c     |  5 -----
> >  drivers/media/platform/amphion/vdec.c                |  2 --
> >  drivers/media/platform/amphion/venc.c                |  2 --
> >  .../media/platform/chips-media/coda/coda-common.c    |  4 ----
> >  drivers/media/platform/imagination/e5010-jpeg-enc.c  |  4 ----
> >  drivers/media/platform/m2m-deinterlace.c             |  7 -------
> >  drivers/media/platform/mediatek/jpeg/mtk_jpeg_core.c |  7 -------
> >  .../mediatek/vcodec/decoder/mtk_vcodec_dec.c         |  7 -------
> >  .../vcodec/decoder/vdec/vdec_av1_req_lat_if.c        |  2 --
> >  .../vcodec/decoder/vdec/vdec_vp9_req_lat_if.c        |  2 --
> >  .../mediatek/vcodec/encoder/mtk_vcodec_enc.c         |  8 --------
> >  drivers/media/platform/nxp/dw100/dw100.c             |  7 -------
> >  drivers/media/platform/nxp/imx-jpeg/mxc-jpeg.c       |  4 ----
> >  drivers/media/platform/nxp/imx-pxp.c                 |  7 -------
> >  drivers/media/platform/nxp/imx8-isi/imx8-isi-m2m.c   |  2 --
> >  drivers/media/platform/nxp/mx2_emmaprp.c             |  7 -------
> >  drivers/media/platform/qcom/iris/iris_vdec.c         |  2 --
> >  drivers/media/platform/qcom/venus/vdec.c             |  2 --
> >  drivers/media/platform/qcom/venus/venc.c             |  2 --
> >  drivers/media/platform/renesas/rcar_fdp1.c           |  3 ---
> >  drivers/media/platform/renesas/rcar_jpu.c            |  8 --------
> >  drivers/media/platform/rockchip/rga/rga.c            |  4 ----
> >  drivers/media/platform/samsung/s5p-g2d/g2d.c         |  4 ----
> >  drivers/media/platform/samsung/s5p-jpeg/jpeg-core.c  |  7 -------
> >  drivers/media/platform/st/stm32/dma2d/dma2d.c        |  5 -----
> >  drivers/media/platform/ti/vpe/vpe.c                  |  7 -------
> >  drivers/media/test-drivers/vicodec/vicodec-core.c    |  7 -------
> >  drivers/media/test-drivers/vim2m.c                   | 12 ------------
> >  drivers/media/v4l2-core/v4l2-mem2mem.c               | 12 +-----------
> >  include/media/v4l2-mem2mem.h                         |  3 +++
> >  31 files changed, 4 insertions(+), 153 deletions(-)
> > 
> > 
> > base-commit: e5f0a698b34ed76002dc5cff3804a61c80233a7a

-- 
Regards,

Laurent Pinchart

Re: [PATCH 11/25] media: imx-jpeg: Drop unneeded v4l2_m2m_get_vq() NULL check

[Frank Li]

On Wed, Oct 08, 2025 at 08:50:38PM +0300, Laurent Pinchart wrote:
> The v4l2_m2m_get_vq() function never returns NULL. The check may have
> been intended to catch invalid format types, but that's not needed as
> the V4L2 core picks the appropriate VIDIOC_S_FMT ioctl handler based on
> the format type, so the type can't be incorrect. Drop the unneeded
> return value check.
>
> Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>

Reviewed-by: Frank Li <Frank.Li@nxp.com>

> ---
>  drivers/media/platform/nxp/imx-jpeg/mxc-jpeg.c | 4 ----
>  1 file changed, 4 deletions(-)
>
> diff --git a/drivers/media/platform/nxp/imx-jpeg/mxc-jpeg.c b/drivers/media/platform/nxp/imx-jpeg/mxc-jpeg.c
> index 8681dd193033..37e0670f98c5 100644
> --- a/drivers/media/platform/nxp/imx-jpeg/mxc-jpeg.c
> +++ b/drivers/media/platform/nxp/imx-jpeg/mxc-jpeg.c
> @@ -2492,8 +2492,6 @@ static int mxc_jpeg_s_fmt(struct mxc_jpeg_ctx *ctx,
>  	struct mxc_jpeg_dev *jpeg = ctx->mxc_jpeg;
>
>  	vq = v4l2_m2m_get_vq(ctx->fh.m2m_ctx, f->type);
> -	if (!vq)
> -		return -EINVAL;
>
>  	if (vb2_is_busy(vq)) {
>  		v4l2_err(&jpeg->v4l2_dev, "queue busy\n");
> @@ -2529,8 +2527,6 @@ static int mxc_jpeg_s_fmt_vid_out(struct file *file, void *priv,
>  		return 0;
>
>  	dst_vq = v4l2_m2m_get_vq(ctx->fh.m2m_ctx, cap_type);
> -	if (!dst_vq)
> -		return -EINVAL;
>
>  	if (vb2_is_busy(dst_vq))
>  		return 0;
> --
> Regards,
>
> Laurent Pinchart
>

Re: [PATCH 12/25] media: imx-pxp: Drop unneeded v4l2_m2m_get_vq() NULL check

[Frank Li]

On Wed, Oct 08, 2025 at 08:50:39PM +0300, Laurent Pinchart wrote:
> The v4l2_m2m_get_vq() function never returns NULL.
>
> In the set format handler, the check may have been intended to catch
> invalid format types, but that's not needed as the V4L2 core picks the
> appropriate VIDIOC_S_FMT ioctl handler based on the format type, so the
> type can't be incorrect.
>
> In the get format handler, the return value is not used for any purpose
> other than the NULL check, which was therefore probably intended to
> catch invalid format types. That's not needed for the same reason as in
> the set format handler.
>
> Drop the unneeded return value checks and, as the function has no side
> effect, the unneeded function call as well.
>
> Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
> ---

Reviewed-by: Frank Li <Frank.Li@nxp.com>

>  drivers/media/platform/nxp/imx-pxp.c | 7 -------
>  1 file changed, 7 deletions(-)
>
> diff --git a/drivers/media/platform/nxp/imx-pxp.c b/drivers/media/platform/nxp/imx-pxp.c
> index 7f8ffbac582f..5386650ce194 100644
> --- a/drivers/media/platform/nxp/imx-pxp.c
> +++ b/drivers/media/platform/nxp/imx-pxp.c
> @@ -1180,13 +1180,8 @@ static int pxp_enum_fmt_vid_out(struct file *file, void *priv,
>
>  static int pxp_g_fmt(struct pxp_ctx *ctx, struct v4l2_format *f)
>  {
> -	struct vb2_queue *vq;
>  	struct pxp_q_data *q_data;
>
> -	vq = v4l2_m2m_get_vq(ctx->fh.m2m_ctx, f->type);
> -	if (!vq)
> -		return -EINVAL;
> -
>  	q_data = get_q_data(ctx, f->type);
>
>  	f->fmt.pix.width	= q_data->width;
> @@ -1329,8 +1324,6 @@ static int pxp_s_fmt(struct pxp_ctx *ctx, struct v4l2_format *f)
>  	struct vb2_queue *vq;
>
>  	vq = v4l2_m2m_get_vq(ctx->fh.m2m_ctx, f->type);
> -	if (!vq)
> -		return -EINVAL;
>
>  	q_data = get_q_data(ctx, f->type);
>  	if (!q_data)
> --
> Regards,
>
> Laurent Pinchart
>

Re: [PATCH 13/25] media: nxp: imx8-isi: Drop unneeded v4l2_m2m_get_vq() NULL check

[Frank Li]

On Wed, Oct 08, 2025 at 08:50:40PM +0300, Laurent Pinchart wrote:
> The v4l2_m2m_get_vq() function never returns NULL. The check may have
> been intended to catch invalid format types, but that's not needed as
> the V4L2 core picks the appropriate VIDIOC_S_FMT ioctl handler based on
> the format type, so the type can't be incorrect. Drop the unneeded
> return value check.
>
> Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
> ---

Reviewed-by: Frank Li <Frank.Li@nxp.com>

>  drivers/media/platform/nxp/imx8-isi/imx8-isi-m2m.c | 2 --
>  1 file changed, 2 deletions(-)
>
> diff --git a/drivers/media/platform/nxp/imx8-isi/imx8-isi-m2m.c b/drivers/media/platform/nxp/imx8-isi/imx8-isi-m2m.c
> index 6822c2f7fc69..675f1d2b65d9 100644
> --- a/drivers/media/platform/nxp/imx8-isi/imx8-isi-m2m.c
> +++ b/drivers/media/platform/nxp/imx8-isi/imx8-isi-m2m.c
> @@ -554,8 +554,6 @@ static int mxc_isi_m2m_s_fmt_vid(struct file *file, void *fh,
>  	struct vb2_queue *vq;
>
>  	vq = v4l2_m2m_get_vq(ctx->fh.m2m_ctx, f->type);
> -	if (!vq)
> -		return -EINVAL;
>
>  	if (vb2_is_busy(vq))
>  		return -EBUSY;
> --
> Regards,
>
> Laurent Pinchart
>

Re: [PATCH 12/25] media: imx-pxp: Drop unneeded v4l2_m2m_get_vq() NULL check

[Philipp Zabel]

On Mi, 2025-10-08 at 20:50 +0300, Laurent Pinchart wrote:
> The v4l2_m2m_get_vq() function never returns NULL.
> 
> In the set format handler, the check may have been intended to catch
> invalid format types, but that's not needed as the V4L2 core picks the
> appropriate VIDIOC_S_FMT ioctl handler based on the format type, so the
> type can't be incorrect.
> 
> In the get format handler, the return value is not used for any purpose
> other than the NULL check, which was therefore probably intended to
> catch invalid format types. That's not needed for the same reason as in
> the set format handler.
> 
> Drop the unneeded return value checks and, as the function has no side
> effect, the unneeded function call as well.
> 
> Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
> ---
>  drivers/media/platform/nxp/imx-pxp.c | 7 -------
>  1 file changed, 7 deletions(-)
> 
> diff --git a/drivers/media/platform/nxp/imx-pxp.c b/drivers/media/platform/nxp/imx-pxp.c
> index 7f8ffbac582f..5386650ce194 100644
> --- a/drivers/media/platform/nxp/imx-pxp.c
> +++ b/drivers/media/platform/nxp/imx-pxp.c
> @@ -1180,13 +1180,8 @@ static int pxp_enum_fmt_vid_out(struct file *file, void *priv,
>  
>  static int pxp_g_fmt(struct pxp_ctx *ctx, struct v4l2_format *f)
>  {
> -	struct vb2_queue *vq;
>  	struct pxp_q_data *q_data;
>  
> -	vq = v4l2_m2m_get_vq(ctx->fh.m2m_ctx, f->type);
> -	if (!vq)
> -		return -EINVAL;
> -
>  	q_data = get_q_data(ctx, f->type);
>  
>  	f->fmt.pix.width	= q_data->width;
> @@ -1329,8 +1324,6 @@ static int pxp_s_fmt(struct pxp_ctx *ctx, struct v4l2_format *f)
>  	struct vb2_queue *vq;
>  
>  	vq = v4l2_m2m_get_vq(ctx->fh.m2m_ctx, f->type);
> -	if (!vq)
> -		return -EINVAL;
>  
>  	q_data = get_q_data(ctx, f->type);
>  	if (!q_data)


Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de>

regards
Philipp