Re: [PATCH v7 2/3] v4l: ioctl: Use %p4cc printk modifier to print FourCC codes

[Andy Shevchenko <andriy.shevchenko@linux.intel.com>]

On Mon, Feb 15, 2021 at 01:40:29PM +0200, Sakari Ailus wrote:
> Now that we can print FourCC codes directly using printk, make use of the
> feature in V4L2 core.

Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
See also below.

> Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
> ---
>  drivers/media/v4l2-core/v4l2-ioctl.c | 85 +++++++---------------------
>  1 file changed, 21 insertions(+), 64 deletions(-)
> 
> diff --git a/drivers/media/v4l2-core/v4l2-ioctl.c b/drivers/media/v4l2-core/v4l2-ioctl.c
> index 31d1342e61e8..31662c3a8c9e 100644
> --- a/drivers/media/v4l2-core/v4l2-ioctl.c
> +++ b/drivers/media/v4l2-core/v4l2-ioctl.c
> @@ -265,13 +265,9 @@ static void v4l_print_fmtdesc(const void *arg, bool write_only)
>  {
>  	const struct v4l2_fmtdesc *p = arg;
>  
> -	pr_cont("index=%u, type=%s, flags=0x%x, pixelformat=%c%c%c%c, mbus_code=0x%04x, description='%.*s'\n",
> +	pr_cont("index=%u, type=%s, flags=0x%x, pixelformat=%p4cc, mbus_code=0x%04x, description='%.*s'\n",
>  		p->index, prt_names(p->type, v4l2_type_names),
> -		p->flags, (p->pixelformat & 0xff),
> -		(p->pixelformat >>  8) & 0xff,
> -		(p->pixelformat >> 16) & 0xff,
> -		(p->pixelformat >> 24) & 0xff,
> -		p->mbus_code,
> +		p->flags, &p->pixelformat, p->mbus_code,
>  		(int)sizeof(p->description), p->description);
>  }
>  
> @@ -293,12 +289,8 @@ static void v4l_print_format(const void *arg, bool write_only)
>  	case V4L2_BUF_TYPE_VIDEO_CAPTURE:
>  	case V4L2_BUF_TYPE_VIDEO_OUTPUT:
>  		pix = &p->fmt.pix;
> -		pr_cont(", width=%u, height=%u, pixelformat=%c%c%c%c, field=%s, bytesperline=%u, sizeimage=%u, colorspace=%d, flags=0x%x, ycbcr_enc=%u, quantization=%u, xfer_func=%u\n",
> -			pix->width, pix->height,
> -			(pix->pixelformat & 0xff),
> -			(pix->pixelformat >>  8) & 0xff,
> -			(pix->pixelformat >> 16) & 0xff,
> -			(pix->pixelformat >> 24) & 0xff,
> +		pr_cont(", width=%u, height=%u, pixelformat=%p4cc, field=%s, bytesperline=%u, sizeimage=%u, colorspace=%d, flags=0x%x, ycbcr_enc=%u, quantization=%u, xfer_func=%u\n",
> +			pix->width, pix->height, &pix->pixelformat,
>  			prt_names(pix->field, v4l2_field_names),
>  			pix->bytesperline, pix->sizeimage,
>  			pix->colorspace, pix->flags, pix->ycbcr_enc,
> @@ -307,12 +299,8 @@ static void v4l_print_format(const void *arg, bool write_only)
>  	case V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE:
>  	case V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE:
>  		mp = &p->fmt.pix_mp;
> -		pr_cont(", width=%u, height=%u, format=%c%c%c%c, field=%s, colorspace=%d, num_planes=%u, flags=0x%x, ycbcr_enc=%u, quantization=%u, xfer_func=%u\n",
> -			mp->width, mp->height,
> -			(mp->pixelformat & 0xff),
> -			(mp->pixelformat >>  8) & 0xff,
> -			(mp->pixelformat >> 16) & 0xff,
> -			(mp->pixelformat >> 24) & 0xff,
> +		pr_cont(", width=%u, height=%u, format=%p4cc, field=%s, colorspace=%d, num_planes=%u, flags=0x%x, ycbcr_enc=%u, quantization=%u, xfer_func=%u\n",
> +			mp->width, mp->height, &mp->pixelformat,
>  			prt_names(mp->field, v4l2_field_names),
>  			mp->colorspace, mp->num_planes, mp->flags,
>  			mp->ycbcr_enc, mp->quantization, mp->xfer_func);
> @@ -337,13 +325,9 @@ static void v4l_print_format(const void *arg, bool write_only)
>  	case V4L2_BUF_TYPE_VBI_CAPTURE:
>  	case V4L2_BUF_TYPE_VBI_OUTPUT:
>  		vbi = &p->fmt.vbi;
> -		pr_cont(", sampling_rate=%u, offset=%u, samples_per_line=%u, sample_format=%c%c%c%c, start=%u,%u, count=%u,%u\n",
> +		pr_cont(", sampling_rate=%u, offset=%u, samples_per_line=%u, sample_format=%p4cc, start=%u,%u, count=%u,%u\n",
>  			vbi->sampling_rate, vbi->offset,
> -			vbi->samples_per_line,
> -			(vbi->sample_format & 0xff),
> -			(vbi->sample_format >>  8) & 0xff,
> -			(vbi->sample_format >> 16) & 0xff,
> -			(vbi->sample_format >> 24) & 0xff,
> +			vbi->samples_per_line, &vbi->sample_format,
>  			vbi->start[0], vbi->start[1],
>  			vbi->count[0], vbi->count[1]);
>  		break;
> @@ -360,21 +344,13 @@ static void v4l_print_format(const void *arg, bool write_only)
>  	case V4L2_BUF_TYPE_SDR_CAPTURE:
>  	case V4L2_BUF_TYPE_SDR_OUTPUT:
>  		sdr = &p->fmt.sdr;
> -		pr_cont(", pixelformat=%c%c%c%c\n",
> -			(sdr->pixelformat >>  0) & 0xff,
> -			(sdr->pixelformat >>  8) & 0xff,
> -			(sdr->pixelformat >> 16) & 0xff,
> -			(sdr->pixelformat >> 24) & 0xff);
> +		pr_cont(", pixelformat=%p4cc\n", &sdr->pixelformat);
>  		break;
>  	case V4L2_BUF_TYPE_META_CAPTURE:
>  	case V4L2_BUF_TYPE_META_OUTPUT:
>  		meta = &p->fmt.meta;
> -		pr_cont(", dataformat=%c%c%c%c, buffersize=%u\n",
> -			(meta->dataformat >>  0) & 0xff,
> -			(meta->dataformat >>  8) & 0xff,
> -			(meta->dataformat >> 16) & 0xff,
> -			(meta->dataformat >> 24) & 0xff,
> -			meta->buffersize);
> +		pr_cont(", dataformat=%p4cc, buffersize=%u\n",
> +			&meta->dataformat, meta->buffersize);
>  		break;
>  	}
>  }
> @@ -383,15 +359,10 @@ static void v4l_print_framebuffer(const void *arg, bool write_only)
>  {
>  	const struct v4l2_framebuffer *p = arg;
>  
> -	pr_cont("capability=0x%x, flags=0x%x, base=0x%p, width=%u, height=%u, pixelformat=%c%c%c%c, bytesperline=%u, sizeimage=%u, colorspace=%d\n",
> -			p->capability, p->flags, p->base,
> -			p->fmt.width, p->fmt.height,
> -			(p->fmt.pixelformat & 0xff),
> -			(p->fmt.pixelformat >>  8) & 0xff,
> -			(p->fmt.pixelformat >> 16) & 0xff,
> -			(p->fmt.pixelformat >> 24) & 0xff,
> -			p->fmt.bytesperline, p->fmt.sizeimage,
> -			p->fmt.colorspace);
> +	pr_cont("capability=0x%x, flags=0x%x, base=0x%p, width=%u, height=%u, pixelformat=%p4cc, bytesperline=%u, sizeimage=%u, colorspace=%d\n",
> +		p->capability, p->flags, p->base, p->fmt.width, p->fmt.height,
> +		&p->fmt.pixelformat, p->fmt.bytesperline, p->fmt.sizeimage,
> +		p->fmt.colorspace);
>  }
>  
>  static void v4l_print_buftype(const void *arg, bool write_only)
> @@ -761,13 +732,8 @@ static void v4l_print_frmsizeenum(const void *arg, bool write_only)
>  {
>  	const struct v4l2_frmsizeenum *p = arg;
>  
> -	pr_cont("index=%u, pixelformat=%c%c%c%c, type=%u",
> -			p->index,
> -			(p->pixel_format & 0xff),
> -			(p->pixel_format >>  8) & 0xff,
> -			(p->pixel_format >> 16) & 0xff,
> -			(p->pixel_format >> 24) & 0xff,
> -			p->type);
> +	pr_cont("index=%u, pixelformat=%p4cc, type=%u",
> +		p->index, &p->pixel_format, p->type);
>  	switch (p->type) {
>  	case V4L2_FRMSIZE_TYPE_DISCRETE:
>  		pr_cont(", wxh=%ux%u\n",
> @@ -793,13 +759,8 @@ static void v4l_print_frmivalenum(const void *arg, bool write_only)
>  {
>  	const struct v4l2_frmivalenum *p = arg;
>  
> -	pr_cont("index=%u, pixelformat=%c%c%c%c, wxh=%ux%u, type=%u",
> -			p->index,
> -			(p->pixel_format & 0xff),
> -			(p->pixel_format >>  8) & 0xff,
> -			(p->pixel_format >> 16) & 0xff,
> -			(p->pixel_format >> 24) & 0xff,
> -			p->width, p->height, p->type);
> +	pr_cont("index=%u, pixelformat=%p4cc, wxh=%ux%u, type=%u",
> +		p->index, &p->pixel_format, p->width, p->height, p->type);
>  	switch (p->type) {
>  	case V4L2_FRMIVAL_TYPE_DISCRETE:
>  		pr_cont(", fps=%d/%d\n",
> @@ -1459,12 +1420,8 @@ static void v4l_fill_fmtdesc(struct v4l2_fmtdesc *fmt)
>  				return;
>  			WARN(1, "Unknown pixelformat 0x%08x\n", fmt->pixelformat);
>  			flags = 0;
> -			snprintf(fmt->description, sz, "%c%c%c%c%s",
> -					(char)(fmt->pixelformat & 0x7f),
> -					(char)((fmt->pixelformat >> 8) & 0x7f),
> -					(char)((fmt->pixelformat >> 16) & 0x7f),
> -					(char)((fmt->pixelformat >> 24) & 0x7f),
> -					(fmt->pixelformat & (1UL << 31)) ? "-BE" : "");

I'm wondering how it handled before the characters 0x80 or so...

> +			snprintf(fmt->description, sz, "%p4cc",
> +				 &fmt->pixelformat);
>  			break;
>  		}
>  	}
> -- 
> 2.29.2
> 

-- 
With Best Regards,
Andy Shevchenko