* [PATCH-next] media: s2255drv: Remove unneeded if else blocks
@ 2018-01-24 21:40 Christopher Díaz Riveros
2018-01-25 8:46 ` walter harms
0 siblings, 1 reply; 2+ messages in thread
From: Christopher Díaz Riveros @ 2018-01-24 21:40 UTC (permalink / raw)
To: mchehab, hans.verkuil, arvind.yadav.cs, dean, keescook, bhumirks,
sakari.ailus
Cc: linux-media, linux-kernel, kernel-janitors
Given the following definitions from s2255drv.c
#define LINE_SZ_4CIFS_NTSC 640
#define LINE_SZ_2CIFS_NTSC 640
#define LINE_SZ_1CIFS_NTSC 320
and
#define LINE_SZ_4CIFS_PAL 704
#define LINE_SZ_2CIFS_PAL 704
#define LINE_SZ_1CIFS_PAL 352
f->fmt.pix.width possible values can be reduced to
LINE_SZ_4CIFS_NTSC or LINE_SZ_1CIFS_NTSC.
This patch removes unneeded if else blocks in vidioc_try_fmt_vid_cap
function.
This issue was detected by using the Coccinelle software.
Signed-off-by: Christopher Díaz Riveros <chrisadr@gentoo.org>
---
drivers/media/usb/s2255/s2255drv.c | 8 --------
1 file changed, 8 deletions(-)
diff --git a/drivers/media/usb/s2255/s2255drv.c b/drivers/media/usb/s2255/s2255drv.c
index 8c2a86d71e8a..a00a15f55d37 100644
--- a/drivers/media/usb/s2255/s2255drv.c
+++ b/drivers/media/usb/s2255/s2255drv.c
@@ -803,10 +803,6 @@ static int vidioc_try_fmt_vid_cap(struct file *file, void *priv,
}
if (f->fmt.pix.width >= LINE_SZ_4CIFS_NTSC)
f->fmt.pix.width = LINE_SZ_4CIFS_NTSC;
- else if (f->fmt.pix.width >= LINE_SZ_2CIFS_NTSC)
- f->fmt.pix.width = LINE_SZ_2CIFS_NTSC;
- else if (f->fmt.pix.width >= LINE_SZ_1CIFS_NTSC)
- f->fmt.pix.width = LINE_SZ_1CIFS_NTSC;
else
f->fmt.pix.width = LINE_SZ_1CIFS_NTSC;
} else {
@@ -820,10 +816,6 @@ static int vidioc_try_fmt_vid_cap(struct file *file, void *priv,
}
if (f->fmt.pix.width >= LINE_SZ_4CIFS_PAL)
f->fmt.pix.width = LINE_SZ_4CIFS_PAL;
- else if (f->fmt.pix.width >= LINE_SZ_2CIFS_PAL)
- f->fmt.pix.width = LINE_SZ_2CIFS_PAL;
- else if (f->fmt.pix.width >= LINE_SZ_1CIFS_PAL)
- f->fmt.pix.width = LINE_SZ_1CIFS_PAL;
else
f->fmt.pix.width = LINE_SZ_1CIFS_PAL;
}
--
2.16.0
^ permalink raw reply related [flat|nested] 2+ messages in thread
* Re: [PATCH-next] media: s2255drv: Remove unneeded if else blocks
2018-01-24 21:40 [PATCH-next] media: s2255drv: Remove unneeded if else blocks Christopher Díaz Riveros
@ 2018-01-25 8:46 ` walter harms
0 siblings, 0 replies; 2+ messages in thread
From: walter harms @ 2018-01-25 8:46 UTC (permalink / raw)
To: Christopher Díaz Riveros
Cc: mchehab, hans.verkuil, arvind.yadav.cs, dean, keescook, bhumirks,
sakari.ailus, linux-media, linux-kernel, kernel-janitors
Am 24.01.2018 22:40, schrieb Christopher Díaz Riveros:
> Given the following definitions from s2255drv.c
>
> #define LINE_SZ_4CIFS_NTSC 640
> #define LINE_SZ_2CIFS_NTSC 640
> #define LINE_SZ_1CIFS_NTSC 320
>
> and
>
> #define LINE_SZ_4CIFS_PAL 704
> #define LINE_SZ_2CIFS_PAL 704
> #define LINE_SZ_1CIFS_PAL 352
>
> f->fmt.pix.width possible values can be reduced to
> LINE_SZ_4CIFS_NTSC or LINE_SZ_1CIFS_NTSC.
>
> This patch removes unneeded if else blocks in vidioc_try_fmt_vid_cap
> function.
>
> This issue was detected by using the Coccinelle software.
>
> Signed-off-by: Christopher Díaz Riveros <chrisadr@gentoo.org>
mmmh, yes and no.
i guess the author tries to document the change from 4->2->1
The whole thing gets more obvoius when you use hex and look at the bits:
704 = 0x2C0 = 001011000000
640 = 0x280 = 001010000000
352 = 0x160 = 000101100000
320 = 0x140 = 000101000000
so they only flip one bit and shift the mask. perhaps you can use that
to simplify the code ?
re
wh
> ---
> drivers/media/usb/s2255/s2255drv.c | 8 --------
> 1 file changed, 8 deletions(-)
>
> diff --git a/drivers/media/usb/s2255/s2255drv.c b/drivers/media/usb/s2255/s2255drv.c
> index 8c2a86d71e8a..a00a15f55d37 100644
> --- a/drivers/media/usb/s2255/s2255drv.c
> +++ b/drivers/media/usb/s2255/s2255drv.c
> @@ -803,10 +803,6 @@ static int vidioc_try_fmt_vid_cap(struct file *file, void *priv,
> }
> if (f->fmt.pix.width >= LINE_SZ_4CIFS_NTSC)
> f->fmt.pix.width = LINE_SZ_4CIFS_NTSC;
> - else if (f->fmt.pix.width >= LINE_SZ_2CIFS_NTSC)
> - f->fmt.pix.width = LINE_SZ_2CIFS_NTSC;
> - else if (f->fmt.pix.width >= LINE_SZ_1CIFS_NTSC)
> - f->fmt.pix.width = LINE_SZ_1CIFS_NTSC;
> else
> f->fmt.pix.width = LINE_SZ_1CIFS_NTSC;
> } else {
> @@ -820,10 +816,6 @@ static int vidioc_try_fmt_vid_cap(struct file *file, void *priv,
> }
> if (f->fmt.pix.width >= LINE_SZ_4CIFS_PAL)
> f->fmt.pix.width = LINE_SZ_4CIFS_PAL;
> - else if (f->fmt.pix.width >= LINE_SZ_2CIFS_PAL)
> - f->fmt.pix.width = LINE_SZ_2CIFS_PAL;
> - else if (f->fmt.pix.width >= LINE_SZ_1CIFS_PAL)
> - f->fmt.pix.width = LINE_SZ_1CIFS_PAL;
> else
> f->fmt.pix.width = LINE_SZ_1CIFS_PAL;
> }
^ permalink raw reply [flat|nested] 2+ messages in thread
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