Re: [RFC PATCH] vimc: Add colors' order over test image

[Dafna Hirschfeld <dafna.hirschfeld@collabora.com>]

Hi,

On 07.06.20 15:53, Kaaira Gupta wrote:
> Currently there is no method to know if the test image generated by vimc
> is correct (except for comparing it with a known 'correct' image). Add
> text over the test image, representing the correct order of colors.
> 
> I have sent it as an RFC because we can add the text as an optional
> control, and maybe we can print some other useful information as well
> (like vivid does).

Yes, it seems like a good idea to add it as a control of the sensor.

> 
> Signed-off-by: Kaaira Gupta <kgupta@es.iitr.ac.in>
> --->   drivers/media/test-drivers/vimc/Kconfig       | 2 ++
>   drivers/media/test-drivers/vimc/vimc-core.c   | 9 +++++++++
>   drivers/media/test-drivers/vimc/vimc-sensor.c | 8 ++++++++
>   3 files changed, 19 insertions(+)
> 
> diff --git a/drivers/media/test-drivers/vimc/Kconfig b/drivers/media/test-drivers/vimc/Kconfig
> index 4068a67585f9..da4b2ad6e40c 100644
> --- a/drivers/media/test-drivers/vimc/Kconfig
> +++ b/drivers/media/test-drivers/vimc/Kconfig
> @@ -2,6 +2,8 @@
>   config VIDEO_VIMC
>   	tristate "Virtual Media Controller Driver (VIMC)"
>   	depends on VIDEO_DEV && VIDEO_V4L2
> +	select FONT_SUPPORT
> +	select FONT_8x16
>   	select MEDIA_CONTROLLER
>   	select VIDEO_V4L2_SUBDEV_API
>   	select VIDEOBUF2_VMALLOC
> diff --git a/drivers/media/test-drivers/vimc/vimc-core.c b/drivers/media/test-drivers/vimc/vimc-core.c
> index 11210aaa2551..8142bfbcbd49 100644
> --- a/drivers/media/test-drivers/vimc/vimc-core.c
> +++ b/drivers/media/test-drivers/vimc/vimc-core.c
> @@ -5,10 +5,12 @@
>    * Copyright (C) 2015-2017 Helen Koike <helen.fornazier@gmail.com>
>    */
>   
> +#include <linux/font.h>
>   #include <linux/init.h>
>   #include <linux/module.h>
>   #include <linux/platform_device.h>
>   #include <media/media-device.h>
> +#include <media/tpg/v4l2-tpg.h>
>   #include <media/v4l2-device.h>
>   
>   #include "vimc-common.h"
> @@ -265,7 +267,14 @@ static int vimc_probe(struct platform_device *pdev)
>   {
>   	struct vimc_device *vimc;
>   	int ret;
> +	const struct font_desc *font = find_font("VGA8x16");
>   
> +	if (font == NULL) {
> +		pr_err("vimc: could not find font\n");
> +		return -ENODEV;
> +	}
> +
> +	tpg_set_font(font->data);

I think the code that set the format should move to the
code that registers the sensor in vimc-sensor.c

>   	dev_dbg(&pdev->dev, "probe");
>   
>   	vimc = kzalloc(sizeof(*vimc), GFP_KERNEL);
> diff --git a/drivers/media/test-drivers/vimc/vimc-sensor.c b/drivers/media/test-drivers/vimc/vimc-sensor.c
> index a2f09ac9a360..4b13955c502a 100644
> --- a/drivers/media/test-drivers/vimc/vimc-sensor.c
> +++ b/drivers/media/test-drivers/vimc/vimc-sensor.c
> @@ -185,10 +185,18 @@ static const struct v4l2_subdev_pad_ops vimc_sen_pad_ops = {
>   static void *vimc_sen_process_frame(struct vimc_ent_device *ved,
>   				    const void *sink_frame)
>   {
> +	u8 *basep[TPG_MAX_PLANES][2];
> +	char str[100];
>   	struct vimc_sen_device *vsen = container_of(ved, struct vimc_sen_device,
>   						    ved);
>   
> +	tpg_calc_text_basep(&vsen->tpg, basep, 0, vsen->frame);
>   	tpg_fill_plane_buffer(&vsen->tpg, 0, 0, vsen->frame);
> +
> +	snprintf(str, sizeof(str),
> +		 "Order: white, yellow, cyan, green, magenta, red, blue, black");
The colors are generated by the tpg, so I think it should be a feature of the tpg to print the colors.

For example, a function in v4l2-tpg-core.c that get the pattern as an argument and return
this string, or maybe returns a const pointer to the array of colors, or something like that.
Then maybe we can add a control in vivid for the same tpg feature.

Note also that the sensor has a control to change the pattern: vimc_sen_ctrl_test_pattern
So the string depends on that pattern.

Thanks,
Dafna


> +	tpg_gen_text(&vsen->tpg, basep, 1, 1, str);
> +
>   	return vsen->frame;
>   }
>   
>