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

From: Helen Koike
Date: Tue Jun 30 2020 - 09:46:35 EST


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"

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.

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,
>>>