2021-08-18 19:44:03

by Tom Rix

[permalink] [raw]
Subject: [PATCH] media: camss: vfe: simplify vfe_get_wm_sizes()

From: Tom Rix <[email protected]>

Static analysis reports this representative problem
camss-vfe-4-1.c:333: The result of the left shift is undefined because
the left operand is negative
reg |= (height - 1) << 4;
~~~~~~~~~ ^

The is a false positive. height is set in vfe_get_wm_sizes() which
has a switch statement without a default.

Reviewing the switch, the cases contain redundant assignments.
So simplify to assignments.

Signed-off-by: Tom Rix <[email protected]>
---
.../media/platform/qcom/camss/camss-vfe-4-1.c | 20 ++++++-------------
.../media/platform/qcom/camss/camss-vfe-4-7.c | 10 +++-------
.../media/platform/qcom/camss/camss-vfe-4-8.c | 9 +++------
3 files changed, 12 insertions(+), 27 deletions(-)

diff --git a/drivers/media/platform/qcom/camss/camss-vfe-4-1.c b/drivers/media/platform/qcom/camss/camss-vfe-4-1.c
index 7b7c9a0aaab282..42047b11ba529e 100644
--- a/drivers/media/platform/qcom/camss/camss-vfe-4-1.c
+++ b/drivers/media/platform/qcom/camss/camss-vfe-4-1.c
@@ -290,22 +290,14 @@ static void vfe_wm_frame_based(struct vfe_device *vfe, u8 wm, u8 enable)
static void vfe_get_wm_sizes(struct v4l2_pix_format_mplane *pix, u8 plane,
u16 *width, u16 *height, u16 *bytesperline)
{
- switch (pix->pixelformat) {
- case V4L2_PIX_FMT_NV12:
- case V4L2_PIX_FMT_NV21:
- *width = pix->width;
- *height = pix->height;
- *bytesperline = pix->plane_fmt[0].bytesperline;
+ *width = pix->width;
+ *height = pix->height;
+ *bytesperline = pix->plane_fmt[0].bytesperline;
+
+ if (pix->pixelformat == V4L2_PIX_FMT_NV12 ||
+ pix->pixelformat == V4L2_PIX_FMT_NV21)
if (plane == 1)
*height /= 2;
- break;
- case V4L2_PIX_FMT_NV16:
- case V4L2_PIX_FMT_NV61:
- *width = pix->width;
- *height = pix->height;
- *bytesperline = pix->plane_fmt[0].bytesperline;
- break;
- }
}

static void vfe_wm_line_based(struct vfe_device *vfe, u32 wm,
diff --git a/drivers/media/platform/qcom/camss/camss-vfe-4-7.c b/drivers/media/platform/qcom/camss/camss-vfe-4-7.c
index 2836b12ec98915..ab2d57bdf5e71c 100644
--- a/drivers/media/platform/qcom/camss/camss-vfe-4-7.c
+++ b/drivers/media/platform/qcom/camss/camss-vfe-4-7.c
@@ -370,30 +370,26 @@ static int vfe_word_per_line_by_bytes(u32 bytes_per_line)
static void vfe_get_wm_sizes(struct v4l2_pix_format_mplane *pix, u8 plane,
u16 *width, u16 *height, u16 *bytesperline)
{
+ *width = pix->width;
+ *height = pix->height;
+
switch (pix->pixelformat) {
case V4L2_PIX_FMT_NV12:
case V4L2_PIX_FMT_NV21:
- *width = pix->width;
- *height = pix->height;
*bytesperline = pix->plane_fmt[0].bytesperline;
if (plane == 1)
*height /= 2;
break;
case V4L2_PIX_FMT_NV16:
case V4L2_PIX_FMT_NV61:
- *width = pix->width;
- *height = pix->height;
*bytesperline = pix->plane_fmt[0].bytesperline;
break;
case V4L2_PIX_FMT_YUYV:
case V4L2_PIX_FMT_YVYU:
case V4L2_PIX_FMT_VYUY:
case V4L2_PIX_FMT_UYVY:
- *width = pix->width;
- *height = pix->height;
*bytesperline = pix->plane_fmt[plane].bytesperline;
break;
-
}
}

diff --git a/drivers/media/platform/qcom/camss/camss-vfe-4-8.c b/drivers/media/platform/qcom/camss/camss-vfe-4-8.c
index 19519234f727c1..7e6b62c930ac8a 100644
--- a/drivers/media/platform/qcom/camss/camss-vfe-4-8.c
+++ b/drivers/media/platform/qcom/camss/camss-vfe-4-8.c
@@ -343,27 +343,24 @@ static int vfe_word_per_line_by_bytes(u32 bytes_per_line)
static void vfe_get_wm_sizes(struct v4l2_pix_format_mplane *pix, u8 plane,
u16 *width, u16 *height, u16 *bytesperline)
{
+ *width = pix->width;
+ *height = pix->height;
+
switch (pix->pixelformat) {
case V4L2_PIX_FMT_NV12:
case V4L2_PIX_FMT_NV21:
- *width = pix->width;
- *height = pix->height;
*bytesperline = pix->plane_fmt[0].bytesperline;
if (plane == 1)
*height /= 2;
break;
case V4L2_PIX_FMT_NV16:
case V4L2_PIX_FMT_NV61:
- *width = pix->width;
- *height = pix->height;
*bytesperline = pix->plane_fmt[0].bytesperline;
break;
case V4L2_PIX_FMT_YUYV:
case V4L2_PIX_FMT_YVYU:
case V4L2_PIX_FMT_VYUY:
case V4L2_PIX_FMT_UYVY:
- *width = pix->width;
- *height = pix->height;
*bytesperline = pix->plane_fmt[plane].bytesperline;
break;
}
--
2.26.3


2021-08-31 19:14:03

by Robert Foss

[permalink] [raw]
Subject: Re: [PATCH] media: camss: vfe: simplify vfe_get_wm_sizes()

Hey Tom,

Thanks for the patch!

On Wed, 18 Aug 2021 at 21:41, <[email protected]> wrote:
>
> From: Tom Rix <[email protected]>
>
> Static analysis reports this representative problem
> camss-vfe-4-1.c:333: The result of the left shift is undefined because
> the left operand is negative
> reg |= (height - 1) << 4;
> ~~~~~~~~~ ^
>
> The is a false positive. height is set in vfe_get_wm_sizes() which
> has a switch statement without a default.
>
> Reviewing the switch, the cases contain redundant assignments.
> So simplify to assignments.
>
> Signed-off-by: Tom Rix <[email protected]>
> ---
> .../media/platform/qcom/camss/camss-vfe-4-1.c | 20 ++++++-------------
> .../media/platform/qcom/camss/camss-vfe-4-7.c | 10 +++-------
> .../media/platform/qcom/camss/camss-vfe-4-8.c | 9 +++------
> 3 files changed, 12 insertions(+), 27 deletions(-)
>
> diff --git a/drivers/media/platform/qcom/camss/camss-vfe-4-1.c b/drivers/media/platform/qcom/camss/camss-vfe-4-1.c
> index 7b7c9a0aaab282..42047b11ba529e 100644
> --- a/drivers/media/platform/qcom/camss/camss-vfe-4-1.c
> +++ b/drivers/media/platform/qcom/camss/camss-vfe-4-1.c
> @@ -290,22 +290,14 @@ static void vfe_wm_frame_based(struct vfe_device *vfe, u8 wm, u8 enable)
> static void vfe_get_wm_sizes(struct v4l2_pix_format_mplane *pix, u8 plane,
> u16 *width, u16 *height, u16 *bytesperline)
> {
> - switch (pix->pixelformat) {
> - case V4L2_PIX_FMT_NV12:
> - case V4L2_PIX_FMT_NV21:
> - *width = pix->width;
> - *height = pix->height;
> - *bytesperline = pix->plane_fmt[0].bytesperline;
> + *width = pix->width;
> + *height = pix->height;
> + *bytesperline = pix->plane_fmt[0].bytesperline;
> +
> + if (pix->pixelformat == V4L2_PIX_FMT_NV12 ||
> + pix->pixelformat == V4L2_PIX_FMT_NV21)
> if (plane == 1)
> *height /= 2;
> - break;
> - case V4L2_PIX_FMT_NV16:
> - case V4L2_PIX_FMT_NV61:
> - *width = pix->width;
> - *height = pix->height;
> - *bytesperline = pix->plane_fmt[0].bytesperline;
> - break;
> - }
> }
>
> static void vfe_wm_line_based(struct vfe_device *vfe, u32 wm,
> diff --git a/drivers/media/platform/qcom/camss/camss-vfe-4-7.c b/drivers/media/platform/qcom/camss/camss-vfe-4-7.c
> index 2836b12ec98915..ab2d57bdf5e71c 100644
> --- a/drivers/media/platform/qcom/camss/camss-vfe-4-7.c
> +++ b/drivers/media/platform/qcom/camss/camss-vfe-4-7.c
> @@ -370,30 +370,26 @@ static int vfe_word_per_line_by_bytes(u32 bytes_per_line)
> static void vfe_get_wm_sizes(struct v4l2_pix_format_mplane *pix, u8 plane,
> u16 *width, u16 *height, u16 *bytesperline)
> {
> + *width = pix->width;
> + *height = pix->height;
> +
> switch (pix->pixelformat) {
> case V4L2_PIX_FMT_NV12:
> case V4L2_PIX_FMT_NV21:
> - *width = pix->width;
> - *height = pix->height;
> *bytesperline = pix->plane_fmt[0].bytesperline;
> if (plane == 1)
> *height /= 2;
> break;
> case V4L2_PIX_FMT_NV16:
> case V4L2_PIX_FMT_NV61:
> - *width = pix->width;
> - *height = pix->height;
> *bytesperline = pix->plane_fmt[0].bytesperline;
> break;
> case V4L2_PIX_FMT_YUYV:
> case V4L2_PIX_FMT_YVYU:
> case V4L2_PIX_FMT_VYUY:
> case V4L2_PIX_FMT_UYVY:
> - *width = pix->width;
> - *height = pix->height;
> *bytesperline = pix->plane_fmt[plane].bytesperline;
> break;
> -
> }
> }
>
> diff --git a/drivers/media/platform/qcom/camss/camss-vfe-4-8.c b/drivers/media/platform/qcom/camss/camss-vfe-4-8.c
> index 19519234f727c1..7e6b62c930ac8a 100644
> --- a/drivers/media/platform/qcom/camss/camss-vfe-4-8.c
> +++ b/drivers/media/platform/qcom/camss/camss-vfe-4-8.c
> @@ -343,27 +343,24 @@ static int vfe_word_per_line_by_bytes(u32 bytes_per_line)
> static void vfe_get_wm_sizes(struct v4l2_pix_format_mplane *pix, u8 plane,
> u16 *width, u16 *height, u16 *bytesperline)
> {
> + *width = pix->width;
> + *height = pix->height;
> +
> switch (pix->pixelformat) {
> case V4L2_PIX_FMT_NV12:
> case V4L2_PIX_FMT_NV21:
> - *width = pix->width;
> - *height = pix->height;
> *bytesperline = pix->plane_fmt[0].bytesperline;
> if (plane == 1)
> *height /= 2;
> break;
> case V4L2_PIX_FMT_NV16:
> case V4L2_PIX_FMT_NV61:
> - *width = pix->width;
> - *height = pix->height;
> *bytesperline = pix->plane_fmt[0].bytesperline;
> break;
> case V4L2_PIX_FMT_YUYV:
> case V4L2_PIX_FMT_YVYU:
> case V4L2_PIX_FMT_VYUY:
> case V4L2_PIX_FMT_UYVY:
> - *width = pix->width;
> - *height = pix->height;
> *bytesperline = pix->plane_fmt[plane].bytesperline;
> break;
> }

Reviewed-by: Robert Foss <[email protected]>