Re: [PATCH v2 2/2] media: vimc: Add a control to show test pattern colors' order

[Kieran Bingham]

Hi Kaaira,

On 14/06/2020 21:02, Kaaira Gupta wrote:
> Add a control in VIMC to show the correct order of the colors for a
> given test pattern.
> The control can be accessed by using show_colors_order in v4l2-ctl
> 
> Signed-off-by: Kaaira Gupta <kgupta@xxxxxxxxxxxxx>
> ---
>  drivers/media/test-drivers/vimc/Kconfig       |  2 ++
>  drivers/media/test-drivers/vimc/vimc-common.h |  1 +
>  drivers/media/test-drivers/vimc/vimc-sensor.c | 34 +++++++++++++++++++
>  3 files changed, 37 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-common.h b/drivers/media/test-drivers/vimc/vimc-common.h
> index ae163dec2459..52376ba6146b 100644
> --- a/drivers/media/test-drivers/vimc/vimc-common.h
> +++ b/drivers/media/test-drivers/vimc/vimc-common.h
> @@ -20,6 +20,7 @@
>  #define VIMC_CID_VIMC_CLASS		(0x00f00000 | 1)
>  #define VIMC_CID_TEST_PATTERN		(VIMC_CID_VIMC_BASE + 0)
>  #define VIMC_CID_MEAN_WIN_SIZE		(VIMC_CID_VIMC_BASE + 1)
> +#define VIMC_TEST_PATTERN_ORDER		(VIMC_CID_VIMC_BASE + 2)

This should have the prefix CID like the others. I believe that stands
for "Control ID"

As below, I think it might warrant being a more generic name for the OSD
overlay, as it could display more than just the colour sequence.


>  
>  #define VIMC_FRAME_MAX_WIDTH 4096
>  #define VIMC_FRAME_MAX_HEIGHT 2160
> diff --git a/drivers/media/test-drivers/vimc/vimc-sensor.c b/drivers/media/test-drivers/vimc/vimc-sensor.c
> index a2f09ac9a360..da625f6accce 100644
> --- a/drivers/media/test-drivers/vimc/vimc-sensor.c
> +++ b/drivers/media/test-drivers/vimc/vimc-sensor.c
> @@ -5,6 +5,7 @@
>   * Copyright (C) 2015-2017 Helen Koike <helen.fornazier@xxxxxxxxx>
>   */
>  
> +#include <linux/font.h>
>  #include <linux/v4l2-mediabus.h>
>  #include <linux/vmalloc.h>
>  #include <media/v4l2-ctrls.h>
> @@ -19,6 +20,7 @@ struct vimc_sen_device {
>  	struct v4l2_subdev sd;
>  	struct tpg_data tpg;
>  	u8 *frame;
> +	bool show_colors_order;

I would say it's the 'sequence' 'show_color_sequence' but it's still a
bit long ... but maybe that doesn't really matter.


>  	/* The active format */
>  	struct v4l2_mbus_framefmt mbus_format;
>  	struct v4l2_ctrl_handler hdl;
> @@ -185,10 +187,18 @@ 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;
>  	struct vimc_sen_device *vsen = container_of(ved, struct vimc_sen_device,
>  						    ved);
>  
>  	tpg_fill_plane_buffer(&vsen->tpg, 0, 0, vsen->frame);
> +	if (vsen->show_colors_order) {
> +		tpg_calc_text_basep(&vsen->tpg, basep, 0, vsen->frame);
> +		str = tpg_g_color_order(&vsen->tpg);
> +		tpg_gen_text(&vsen->tpg, basep, 1, 1, str);
> +	}
> +
>  	return vsen->frame;
>  }
>  
> @@ -200,6 +210,14 @@ static int vimc_sen_s_stream(struct v4l2_subdev *sd, int enable)
>  	if (enable) {
>  		const struct vimc_pix_map *vpix;
>  		unsigned int frame_size;
> +		const struct font_desc *font = find_font("VGA8x16");
> +
> +		if (font == NULL) {
> +			pr_err("vimc: could not find font\n");
> +			return -ENODEV;

I wonder if this should instead just disable text rendering instead?

It might be reasonable to compile the kernel without the font-library ?

> +		}
> +
> +		tpg_set_font(font->data);
>  
>  		/* Calculate the frame size */
>  		vpix = vimc_pix_map_by_code(vsen->mbus_format.code);
> @@ -269,6 +287,9 @@ static int vimc_sen_s_ctrl(struct v4l2_ctrl *ctrl)
>  	case V4L2_CID_SATURATION:
>  		tpg_s_saturation(&vsen->tpg, ctrl->val);
>  		break;
> +	case VIMC_TEST_PATTERN_ORDER:
> +		vsen->show_colors_order = ctrl->val;
> +		break;
>  	default:
>  		return -EINVAL;
>  	}
> @@ -307,6 +328,17 @@ static const struct v4l2_ctrl_config vimc_sen_ctrl_test_pattern = {
>  	.qmenu = tpg_pattern_strings,
>  };
>  
> +static const struct v4l2_ctrl_config vimc_sen_ctrl_order = {
> +	.ops = &vimc_sen_ctrl_ops,
> +	.id = VIMC_TEST_PATTERN_ORDER,

Now that you've brought in support for rendering text on the frame, I
wonder if more information should be displayed just like VIVID does.

In that case, it would probably be better to have a more generic control
that enables all of the text OSD with a more generic name.


> +	.name = "Show Colors Order",
> +	.type = V4L2_CTRL_TYPE_BOOLEAN,
> +	.min = 0,
> +	.max = 1,
> +	.step = 1,
> +	.def = 1,
> +};
> +
>  static struct vimc_ent_device *vimc_sen_add(struct vimc_device *vimc,
>  					    const char *vcfg_name)
>  {
> @@ -323,6 +355,7 @@ static struct vimc_ent_device *vimc_sen_add(struct vimc_device *vimc,
>  
>  	v4l2_ctrl_new_custom(&vsen->hdl, &vimc_sen_ctrl_class, NULL);
>  	v4l2_ctrl_new_custom(&vsen->hdl, &vimc_sen_ctrl_test_pattern, NULL);
> +	v4l2_ctrl_new_custom(&vsen->hdl, &vimc_sen_ctrl_order, NULL);
>  	v4l2_ctrl_new_std(&vsen->hdl, &vimc_sen_ctrl_ops,
>  			  V4L2_CID_VFLIP, 0, 1, 1, 0);
>  	v4l2_ctrl_new_std(&vsen->hdl, &vimc_sen_ctrl_ops,
> @@ -362,6 +395,7 @@ static struct vimc_ent_device *vimc_sen_add(struct vimc_device *vimc,
>  
>  	/* Initialize the frame format */
>  	vsen->mbus_format = fmt_default;
> +	vsen->show_colors_order = vimc_sen_ctrl_order.def;
>  
>  	return &vsen->ved;
>  
> 

-- 
Regards
--
Kieran