Re: [PATCH v7 3/3] media: vimc: Add a control to display info on test image

[Kieran Bingham]

Hi Helen, Kaaira,

On 30/06/2020 14:46, Helen Koike wrote:
> Hi Kaaira,
> 
> On 6/30/20 10:25 AM, Kaaira Gupta wrote:
>> On Fri, Jun 26, 2020 at 01:01:03PM -0300, Helen Koike wrote:
>>> Hi Kaaira,
>>>
>>> On 6/26/20 10:07 AM, Kaaira Gupta wrote:
>>>> Add a control in VIMC to display information such as the correct order of
>>>> colors for a given test pattern, brightness, hue, saturation, contrast,
>>>> width and height at sensor over test image.
>>>>
>>>> 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-core.c   | 10 +++
>>>>  drivers/media/test-drivers/vimc/vimc-sensor.c | 70 +++++++++++++++++++
>>>>  4 files changed, 83 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..a289434e75ba 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_CID_OSD_TEXT_MODE		(VIMC_CID_VIMC_BASE + 2)
>>>>  
>>>>  #define VIMC_FRAME_MAX_WIDTH 4096
>>>>  #define VIMC_FRAME_MAX_HEIGHT 2160
>>>> diff --git a/drivers/media/test-drivers/vimc/vimc-core.c b/drivers/media/test-drivers/vimc/vimc-core.c
>>>> index 11210aaa2551..4b0ae6f51d76 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@xxxxxxxxx>
>>>>   */
>>>>  
>>>> +#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"
>>>> @@ -263,11 +265,19 @@ static int vimc_register_devices(struct vimc_device *vimc)
>>>>  
>>>>  static int vimc_probe(struct platform_device *pdev)
>>>>  {
>>>> +	const struct font_desc *font = find_font("VGA8x16");
>>>>  	struct vimc_device *vimc;
>>>>  	int ret;
>>>>  
>>>>  	dev_dbg(&pdev->dev, "probe");
>>>>  
>>>> +	if (!font) {
>>>> +		dev_err(&pdev->dev, "could not find font\n");
>>>> +		return -ENODEV;
>>>> +	}
>>>> +
>>>> +	tpg_set_font(font->data);
>>>> +
>>>>  	vimc = kzalloc(sizeof(*vimc), GFP_KERNEL);
>>>>  	if (!vimc)
>>>>  		return -ENOMEM;
>>>> diff --git a/drivers/media/test-drivers/vimc/vimc-sensor.c b/drivers/media/test-drivers/vimc/vimc-sensor.c
>>>> index a2f09ac9a360..9e4fb3f4d60d 100644
>>>> --- a/drivers/media/test-drivers/vimc/vimc-sensor.c
>>>> +++ b/drivers/media/test-drivers/vimc/vimc-sensor.c
>>>> @@ -19,6 +19,8 @@ struct vimc_sen_device {
>>>>  	struct v4l2_subdev sd;
>>>>  	struct tpg_data tpg;
>>>>  	u8 *frame;
>>>> +	unsigned int osd_mode;
>>>
>>> If you declare the enum outside the below function, this could be type osd_mode instead of unsigned int, what do you think?
>>>
>>>> +	u64 start_stream_ts;
>>>>  	/* The active format */
>>>>  	struct v4l2_mbus_framefmt mbus_format;
>>>>  	struct v4l2_ctrl_handler hdl;
>>>> @@ -187,8 +189,54 @@ static void *vimc_sen_process_frame(struct vimc_ent_device *ved,
>>>>  {
>>>>  	struct vimc_sen_device *vsen = container_of(ved, struct vimc_sen_device,
>>>>  						    ved);
>>>> +	enum osd_mode {OSD_SHOW_ALL = 0, OSD_SHOW_COUNTERS = 1, OSD_SHOW_NONE = 2};
>>>> +	const unsigned int line_height = 16;
>>>> +	u8 *basep[TPG_MAX_PLANES][2];
>>>> +	unsigned int line = 1;
>>>> +	char str[100];
>>>>  
>>>>  	tpg_fill_plane_buffer(&vsen->tpg, 0, 0, vsen->frame);
>>>> +	tpg_calc_text_basep(&vsen->tpg, basep, 0, vsen->frame);
>>>> +	switch (vsen->osd_mode) {
>>>> +	case OSD_SHOW_ALL:
>>>> +		{
>>>
>>> Usually we don't use this curly braces in a case statement, please, check other examples in the code,
>>
>> I have declared variables inside the cases,hence they are not just
>> statements, so I need to use them I think
> 
> Doing this grep:
> 
> git grep -A1 "case.*:" drivers/media | grep -B1 -P "\tstruct"

Aha, yes - they might indeed be needed then because of the local scope
variables...

> 
> I see that the standard is to place the curly braces in the same line of the case statement,
> example: https://elixir.bootlin.com/linux/latest/source/drivers/media/v4l2-core/v4l2-subdev.c#L469
> 
>>
>>>
>>>> +			const char *order = tpg_g_color_order(&vsen->tpg);
>>>
>>> You also don't need this level of identation.
>>
>> I used it because of the braces
> 
> Please check the example above
> 
>>
>>>
>>>> +
>>>> +			tpg_gen_text(&vsen->tpg, basep,
>>>> +				     line++ * line_height, 16, order);
>>>> +			snprintf(str, sizeof(str),
>>>> +				 "brightness %3d, contrast %3d, saturation %3d, hue %d ",
>>>> +				 vsen->tpg.brightness,
>>>> +				 vsen->tpg.contrast,
>>>> +				 vsen->tpg.saturation,
>>>> +				 vsen->tpg.hue);
>>>> +			tpg_gen_text(&vsen->tpg, basep, line++ * line_height,
>>>> +				     16, str);
>>>> +			snprintf(str, sizeof(str), "sensor size: %dx%d",
>>>> +				 vsen->mbus_format.width,
>>>> +				 vsen->mbus_format.height);
>>>> +			tpg_gen_text(&vsen->tpg, basep, line++ * line_height,
>>>> +				     16, str);
>>>> +		}
>>>> +	case OSD_SHOW_COUNTERS:
>>>
>>> Checkpatch gives this error:
>>>
>>> WARNING: Possible switch case/default not preceded by break or fallthrough comment
>>>
>>> You need to add a fallthrough comment (grep for fallthrough to find other examples)
>>
>> Okay, I will add that
>>
>>>
>>>> +		{
>>>> +			unsigned int ms;
>>>> +
>>>> +			ms = (ktime_get_ns() - vsen->start_stream_ts) / 1000000;
>>>> +			snprintf(str, sizeof(str), "%02d:%02d:%02d:%03d",
>>>> +				 (ms / (60 * 60 * 1000)) % 24,
>>>> +				 (ms / (60 * 1000)) % 60,
>>>> +				 (ms / 1000) % 60,
>>>> +				 ms % 1000);
>>>> +			tpg_gen_text(&vsen->tpg, basep, line++ * line_height,
>>>> +				     16, str);
>>>> +			break;
>>>> +		}
>>>> +	case OSD_SHOW_NONE:
>>>
>>> No need this case statement if you have the default below.
>>
>> I added it to make it clearer what default does, should I remove it?
> 
> hmm, I think this depends on your style, but to me, just the "default" statement below makes it
> clear that options not listed above do nothing.
> I think you would also need to add a fallthtough comment.

Consecutive case statements (or the default) statement should not need a
/* fallthrough */. I believe it's only if there is a code block it
becomes required.

--
Kieran


> 
> Or you could just add a comment instead of the case statement in the code, like:
> 
> 	/* case OSD_SHOW_NONE: */
> 
> So it would be clear what this option does.
> 
> Regards,
> Helen
> 
>>
>>>
>>> Regards,
>>> Helen
>>>
>>>> +	default:
>>>> +		break;
>>>> +	}
>>>> +
>>>>  	return vsen->frame;
>>>>  }
>>>>  
>>>> @@ -201,6 +249,8 @@ static int vimc_sen_s_stream(struct v4l2_subdev *sd, int enable)
>>>>  		const struct vimc_pix_map *vpix;
>>>>  		unsigned int frame_size;
>>>>  
>>>> +		vsen->start_stream_ts = ktime_get_ns();
>>>> +
>>>>  		/* Calculate the frame size */
>>>>  		vpix = vimc_pix_map_by_code(vsen->mbus_format.code);
>>>>  		frame_size = vsen->mbus_format.width * vpix->bpp *
>>>> @@ -269,6 +319,9 @@ static int vimc_sen_s_ctrl(struct v4l2_ctrl *ctrl)
>>>>  	case V4L2_CID_SATURATION:
>>>>  		tpg_s_saturation(&vsen->tpg, ctrl->val);
>>>>  		break;
>>>> +	case VIMC_CID_OSD_TEXT_MODE:
>>>> +		vsen->osd_mode = ctrl->val;
>>>> +		break;
>>>>  	default:
>>>>  		return -EINVAL;
>>>>  	}
>>>> @@ -307,6 +360,22 @@ static const struct v4l2_ctrl_config vimc_sen_ctrl_test_pattern = {
>>>>  	.qmenu = tpg_pattern_strings,
>>>>  };
>>>>  
>>>> +static const char * const vimc_ctrl_osd_mode_strings[] = {
>>>> +	"All",
>>>> +	"Counters Only",
>>>> +	"None",
>>>> +	NULL,
>>>> +};
>>>> +
>>>> +static const struct v4l2_ctrl_config vimc_sen_ctrl_osd_mode = {
>>>> +	.ops = &vimc_sen_ctrl_ops,
>>>> +	.id = VIMC_CID_OSD_TEXT_MODE,
>>>> +	.name = "Show Information",
>>>> +	.type = V4L2_CTRL_TYPE_MENU,
>>>> +	.max = ARRAY_SIZE(vimc_ctrl_osd_mode_strings) - 2,
>>>> +	.qmenu = vimc_ctrl_osd_mode_strings,
>>>> +};
>>>> +
>>>>  static struct vimc_ent_device *vimc_sen_add(struct vimc_device *vimc,
>>>>  					    const char *vcfg_name)
>>>>  {
>>>> @@ -323,6 +392,7 @@ 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_osd_mode, 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,
>>>>

-- 
Regards
--
Kieran