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

[Kieran Bingham]

Hi Kaaira,

On 30/06/2020 14:25, 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

The scope of the variables should still be local to the case statement,
even without the braces.

Take them out and check with the compiler of course, but I think it
shoudl be fine.

> 
>>
>>> +			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

I suspect that's why we don't use braces in this instance, to prevent
the indentation getting too far out to the right.

With the braces gone, one less level of indentation should be ok.


> 
>>
>>> +
>>> +			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

The /* fallthrough */ comments are important, as it helps prevent bugs
where the fallthrough was not intentional.

Even though the 'comment' does nothing, it tells the compiler/tools that
you /intentionally/ want to run the code in the next block as well.


> 
>>
>>> +		{
>>> +			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?

I personally would keep it directly above the default. It's not
essential as the default will of course catch it - but I would (where
reasonable) make sure all expected case statement options are declared
in the switch.


I don't think it makes it clearer what the 'default' does, but it does
make it clearer that 'SHOW_NONE' is an option and it will go through
here and ... do nothing ;-)

(where the default statement would be the path for invalid options)

--
Kieran


>>
>> 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