[libcamera-devel,22/25] media: ov5647: Support V4L2_CID_PIXEL_RATE

Message ID 20200623165550.45835-3-jacopo@jmondi.org
State Not Applicable
Delegated to: Jacopo Mondi
Headers show
Series
  • media: ov5647: Support RaspberryPi Camera Module v1
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Commit Message

Jacopo Mondi June 23, 2020, 4:55 p.m. UTC
From: Dave Stevenson <dave.stevenson@raspberrypi.com>

Clients need to know the pixel rate in order to compute exposure
and frame rate values. Advertise it.

Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
Signed-off-by: Jacopo Mondi <jacopo@jmondi.org>
---
 drivers/media/i2c/ov5647.c | 40 +++++++++++++++++++++++++++++++-------
 1 file changed, 33 insertions(+), 7 deletions(-)

Comments

Dafna Hirschfeld June 29, 2020, 5:01 p.m. UTC | #1
On 23.06.20 18:55, Jacopo Mondi wrote:
> From: Dave Stevenson <dave.stevenson@raspberrypi.com>
> 
> Clients need to know the pixel rate in order to compute exposure
> and frame rate values. Advertise it.
> 
> Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
> Signed-off-by: Jacopo Mondi <jacopo@jmondi.org>
> ---
>   drivers/media/i2c/ov5647.c | 40 +++++++++++++++++++++++++++++++-------
>   1 file changed, 33 insertions(+), 7 deletions(-)
> 
> diff --git a/drivers/media/i2c/ov5647.c b/drivers/media/i2c/ov5647.c
> index 35865e56de5f9..218576a05e66b 100644
> --- a/drivers/media/i2c/ov5647.c
> +++ b/drivers/media/i2c/ov5647.c
> @@ -76,6 +76,7 @@ struct regval_list {
>   struct ov5647_mode {
>   	struct v4l2_mbus_framefmt	format;
>   	struct v4l2_rect		crop;
> +	u64				pixel_rate;
>   	struct regval_list		*reg_list;
>   	unsigned int			num_regs;
>   };
> @@ -97,6 +98,7 @@ struct ov5647 {
>   	struct v4l2_ctrl_handler	ctrls;
>   	struct ov5647_mode		*mode;
>   	struct ov5647_mode		*current_mode;
> +	struct v4l2_ctrl		*pixel_rate;
>   };
>   
>   static inline struct ov5647 *to_sensor(struct v4l2_subdev *sd)
> @@ -583,6 +585,7 @@ static struct ov5647_mode ov5647_sbggr8_modes[] = {
>   			.width		= 1280,
>   			.height		= 960,
>   		},
> +		.pixel_rate	= 77291670,
>   		.reg_list	= ov5647_640x480_sbggr8,
>   		.num_regs	= ARRAY_SIZE(ov5647_640x480_sbggr8)
>   	},
> @@ -604,6 +607,7 @@ static struct ov5647_mode ov5647_sbggr10_modes[] = {
>   			.width		= 2592,
>   			.height		= 1944
>   		},
> +		.pixel_rate	= 87500000,
>   		.reg_list	= ov5647_2592x1944_sbggr10,
>   		.num_regs	= ARRAY_SIZE(ov5647_2592x1944_sbggr10)
>   	},
> @@ -622,6 +626,7 @@ static struct ov5647_mode ov5647_sbggr10_modes[] = {
>   			.width		= 1928,
>   			.height		= 1080,
>   		},
> +		.pixel_rate	= 81666700,
>   		.reg_list	= ov5647_1080p30_sbggr10,
>   		.num_regs	= ARRAY_SIZE(ov5647_1080p30_sbggr10)
>   	},
> @@ -640,6 +645,7 @@ static struct ov5647_mode ov5647_sbggr10_modes[] = {
>   			.width		= 2592,
>   			.height		= 1944,
>   		},
> +		.pixel_rate	= 81666700,
>   		.reg_list	= ov5647_2x2binned_sbggr10,
>   		.num_regs	= ARRAY_SIZE(ov5647_2x2binned_sbggr10)
>   	},
> @@ -658,6 +664,7 @@ static struct ov5647_mode ov5647_sbggr10_modes[] = {
>   			.width		= 2560,
>   			.height		= 1920,
>   		},
> +		.pixel_rate	= 55000000,
>   		.reg_list	= ov5647_640x480_sbggr10,
>   		.num_regs	= ARRAY_SIZE(ov5647_640x480_sbggr10)
>   	},
> @@ -1094,6 +1101,10 @@ static int ov5647_set_pad_fmt(struct v4l2_subdev *sd,
>   	/* Update the sensor mode and apply at it at streamon time. */
>   	mutex_lock(&sensor->lock);
>   	sensor->mode = mode;
> +
> +	__v4l2_ctrl_modify_range(sensor->pixel_rate, mode->pixel_rate,
> +				 mode->pixel_rate, 1, mode->pixel_rate);
> +
>   	*fmt = mode->format;
>   	mutex_unlock(&sensor->lock);
>   
> @@ -1295,6 +1306,9 @@ static int ov5647_s_ctrl(struct v4l2_ctrl *ctrl)
>   		return  ov5647_s_analogue_gain(sd, ctrl->val);
>   	case V4L2_CID_EXPOSURE:
>   		return ov5647_s_exposure(sd, ctrl->val);
> +	case V4L2_CID_PIXEL_RATE:
> +		/* Read-only, but we adjust it based on mode. */

Looking at other drivers, I see they don't handle read only controls
in s_ctrl cb. Also the docs (vidioc-queryctrl.rst) says that trying to set a read only control should
return EINVAL

Thanks,
Dafna

> +		return 0;
>   	default:
>   		dev_info(&client->dev,
>   			 "Control (id:0x%x, val:0x%x) not supported\n",
> @@ -1313,7 +1327,7 @@ static int ov5647_init_controls(struct ov5647 *sensor)
>   {
>   	struct i2c_client *client = v4l2_get_subdevdata(&sensor->sd);
>   
> -	v4l2_ctrl_handler_init(&sensor->ctrls, 5);
> +	v4l2_ctrl_handler_init(&sensor->ctrls, 6);
>   
>   	v4l2_ctrl_new_std(&sensor->ctrls, &ov5647_ctrl_ops,
>   			  V4L2_CID_AUTOGAIN, 0, 1, 1, 0);
> @@ -1333,17 +1347,29 @@ static int ov5647_init_controls(struct ov5647 *sensor)
>   	v4l2_ctrl_new_std(&sensor->ctrls, &ov5647_ctrl_ops,
>   			  V4L2_CID_ANALOGUE_GAIN, 16, 1023, 1, 32);
>   
> -	if (sensor->ctrls.error) {
> -		dev_err(&client->dev, "%s Controls initialization failed (%d)\n",
> -			__func__, sensor->ctrls.error);
> -		v4l2_ctrl_handler_free(&sensor->ctrls);
> +	/* By default, PIXEL_RATE is read only, but it does change per mode */
> +	sensor->pixel_rate = v4l2_ctrl_new_std(&sensor->ctrls, &ov5647_ctrl_ops,
> +					       V4L2_CID_PIXEL_RATE,
> +					       sensor->mode->pixel_rate,
> +					       sensor->mode->pixel_rate, 1,
> +					       sensor->mode->pixel_rate);
> +	if (!sensor->pixel_rate)
> +		goto handler_free;
> +	sensor->pixel_rate->flags |= V4L2_CTRL_FLAG_READ_ONLY;
>   
> -		return sensor->ctrls.error;
> -	}
> +	if (sensor->ctrls.error)
> +		goto handler_free;
>   
>   	sensor->sd.ctrl_handler = &sensor->ctrls;
>   
>   	return 0;
> +
> +handler_free:
> +	dev_err(&client->dev, "%s Controls initialization failed (%d)\n",
> +		__func__, sensor->ctrls.error);
> +	v4l2_ctrl_handler_free(&sensor->ctrls);
> +
> +	return sensor->ctrls.error;
>   }
>   
>   static int ov5647_parse_dt(struct ov5647 *sensor, struct device_node *np)
>
Dave Stevenson June 29, 2020, 9:25 p.m. UTC | #2
Hi Dafna

On Mon, 29 Jun 2020 at 18:01, Dafna Hirschfeld
<dafna.hirschfeld@collabora.com> wrote:
>
>
>
> On 23.06.20 18:55, Jacopo Mondi wrote:
> > From: Dave Stevenson <dave.stevenson@raspberrypi.com>
> >
> > Clients need to know the pixel rate in order to compute exposure
> > and frame rate values. Advertise it.
> >
> > Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
> > Signed-off-by: Jacopo Mondi <jacopo@jmondi.org>
> > ---
> >   drivers/media/i2c/ov5647.c | 40 +++++++++++++++++++++++++++++++-------
> >   1 file changed, 33 insertions(+), 7 deletions(-)
> >
> > diff --git a/drivers/media/i2c/ov5647.c b/drivers/media/i2c/ov5647.c
> > index 35865e56de5f9..218576a05e66b 100644
> > --- a/drivers/media/i2c/ov5647.c
> > +++ b/drivers/media/i2c/ov5647.c
> > @@ -76,6 +76,7 @@ struct regval_list {
> >   struct ov5647_mode {
> >       struct v4l2_mbus_framefmt       format;
> >       struct v4l2_rect                crop;
> > +     u64                             pixel_rate;
> >       struct regval_list              *reg_list;
> >       unsigned int                    num_regs;
> >   };
> > @@ -97,6 +98,7 @@ struct ov5647 {
> >       struct v4l2_ctrl_handler        ctrls;
> >       struct ov5647_mode              *mode;
> >       struct ov5647_mode              *current_mode;
> > +     struct v4l2_ctrl                *pixel_rate;
> >   };
> >
> >   static inline struct ov5647 *to_sensor(struct v4l2_subdev *sd)
> > @@ -583,6 +585,7 @@ static struct ov5647_mode ov5647_sbggr8_modes[] = {
> >                       .width          = 1280,
> >                       .height         = 960,
> >               },
> > +             .pixel_rate     = 77291670,
> >               .reg_list       = ov5647_640x480_sbggr8,
> >               .num_regs       = ARRAY_SIZE(ov5647_640x480_sbggr8)
> >       },
> > @@ -604,6 +607,7 @@ static struct ov5647_mode ov5647_sbggr10_modes[] = {
> >                       .width          = 2592,
> >                       .height         = 1944
> >               },
> > +             .pixel_rate     = 87500000,
> >               .reg_list       = ov5647_2592x1944_sbggr10,
> >               .num_regs       = ARRAY_SIZE(ov5647_2592x1944_sbggr10)
> >       },
> > @@ -622,6 +626,7 @@ static struct ov5647_mode ov5647_sbggr10_modes[] = {
> >                       .width          = 1928,
> >                       .height         = 1080,
> >               },
> > +             .pixel_rate     = 81666700,
> >               .reg_list       = ov5647_1080p30_sbggr10,
> >               .num_regs       = ARRAY_SIZE(ov5647_1080p30_sbggr10)
> >       },
> > @@ -640,6 +645,7 @@ static struct ov5647_mode ov5647_sbggr10_modes[] = {
> >                       .width          = 2592,
> >                       .height         = 1944,
> >               },
> > +             .pixel_rate     = 81666700,
> >               .reg_list       = ov5647_2x2binned_sbggr10,
> >               .num_regs       = ARRAY_SIZE(ov5647_2x2binned_sbggr10)
> >       },
> > @@ -658,6 +664,7 @@ static struct ov5647_mode ov5647_sbggr10_modes[] = {
> >                       .width          = 2560,
> >                       .height         = 1920,
> >               },
> > +             .pixel_rate     = 55000000,
> >               .reg_list       = ov5647_640x480_sbggr10,
> >               .num_regs       = ARRAY_SIZE(ov5647_640x480_sbggr10)
> >       },
> > @@ -1094,6 +1101,10 @@ static int ov5647_set_pad_fmt(struct v4l2_subdev *sd,
> >       /* Update the sensor mode and apply at it at streamon time. */
> >       mutex_lock(&sensor->lock);
> >       sensor->mode = mode;
> > +
> > +     __v4l2_ctrl_modify_range(sensor->pixel_rate, mode->pixel_rate,
> > +                              mode->pixel_rate, 1, mode->pixel_rate);
> > +
> >       *fmt = mode->format;
> >       mutex_unlock(&sensor->lock);
> >
> > @@ -1295,6 +1306,9 @@ static int ov5647_s_ctrl(struct v4l2_ctrl *ctrl)
> >               return  ov5647_s_analogue_gain(sd, ctrl->val);
> >       case V4L2_CID_EXPOSURE:
> >               return ov5647_s_exposure(sd, ctrl->val);
> > +     case V4L2_CID_PIXEL_RATE:
> > +             /* Read-only, but we adjust it based on mode. */
>
> Looking at other drivers, I see they don't handle read only controls
> in s_ctrl cb. Also the docs (vidioc-queryctrl.rst) says that trying to set a read only control should
> return EINVAL

It was a while ago that I looked at this, but my memory says that
without a handler here then the call to __v4l2_ctrl_modify_range to
update the value failed. The ranges and default were changed, but the
current value wasn't.

Checking now, yes, without returning 0 here,  __v4l2_ctrl_modify_range
returns -22 (-EINVAL) and v4l2-ctl --list-ctrls afterwards shows
Image Processing Controls

                     pixel_rate 0x009f0902 (int64)  : min=87500000
max=87500000 step=1 default=87500000 value=81666700 flags=read-only

A failure of the framework then and needs fixing there, or is it
correct for the driver to have to implement a set hander if it needs
to update the ranges?
A quick grep implies that ov5647 is the first driver that needs to
update V4L2_CID_PIXEL_RATE based on mode. I'll check in the morning if
things like V4L2_CID_HBLANK behave the same - it may be a control type
issue with 64 bit values.


Interesting that the docs say EINVAL as at least one path in the
framework appears to return -EACCES [1]
Checking it:
pi@raspberrypi:~ $ v4l2-ctl --set-ctrl pixel_rate=42
VIDIOC_S_EXT_CTRLS: failed: Permission denied
Error setting controls: Permission denied
which would imply -EACCES

I am testing on a 5.4 kernel rather than media_tree.git, but there
don't appear to be any significant differences in this area between
the two.

Cheers.
  Dave

[1] https://git.linuxtv.org/media_tree.git/tree/drivers/media/v4l2-core/v4l2-ctrls.c#n4224

> Thanks,
> Dafna
>
> > +             return 0;
> >       default:
> >               dev_info(&client->dev,
> >                        "Control (id:0x%x, val:0x%x) not supported\n",
> > @@ -1313,7 +1327,7 @@ static int ov5647_init_controls(struct ov5647 *sensor)
> >   {
> >       struct i2c_client *client = v4l2_get_subdevdata(&sensor->sd);
> >
> > -     v4l2_ctrl_handler_init(&sensor->ctrls, 5);
> > +     v4l2_ctrl_handler_init(&sensor->ctrls, 6);
> >
> >       v4l2_ctrl_new_std(&sensor->ctrls, &ov5647_ctrl_ops,
> >                         V4L2_CID_AUTOGAIN, 0, 1, 1, 0);
> > @@ -1333,17 +1347,29 @@ static int ov5647_init_controls(struct ov5647 *sensor)
> >       v4l2_ctrl_new_std(&sensor->ctrls, &ov5647_ctrl_ops,
> >                         V4L2_CID_ANALOGUE_GAIN, 16, 1023, 1, 32);
> >
> > -     if (sensor->ctrls.error) {
> > -             dev_err(&client->dev, "%s Controls initialization failed (%d)\n",
> > -                     __func__, sensor->ctrls.error);
> > -             v4l2_ctrl_handler_free(&sensor->ctrls);
> > +     /* By default, PIXEL_RATE is read only, but it does change per mode */
> > +     sensor->pixel_rate = v4l2_ctrl_new_std(&sensor->ctrls, &ov5647_ctrl_ops,
> > +                                            V4L2_CID_PIXEL_RATE,
> > +                                            sensor->mode->pixel_rate,
> > +                                            sensor->mode->pixel_rate, 1,
> > +                                            sensor->mode->pixel_rate);
> > +     if (!sensor->pixel_rate)
> > +             goto handler_free;
> > +     sensor->pixel_rate->flags |= V4L2_CTRL_FLAG_READ_ONLY;
> >
> > -             return sensor->ctrls.error;
> > -     }
> > +     if (sensor->ctrls.error)
> > +             goto handler_free;
> >
> >       sensor->sd.ctrl_handler = &sensor->ctrls;
> >
> >       return 0;
> > +
> > +handler_free:
> > +     dev_err(&client->dev, "%s Controls initialization failed (%d)\n",
> > +             __func__, sensor->ctrls.error);
> > +     v4l2_ctrl_handler_free(&sensor->ctrls);
> > +
> > +     return sensor->ctrls.error;
> >   }
> >
> >   static int ov5647_parse_dt(struct ov5647 *sensor, struct device_node *np)
> >
> _______________________________________________
> libcamera-devel mailing list
> libcamera-devel@lists.libcamera.org
> https://lists.libcamera.org/listinfo/libcamera-devel
Dave Stevenson June 30, 2020, 3:13 p.m. UTC | #3
On Mon, 29 Jun 2020 at 22:25, Dave Stevenson
<dave.stevenson@raspberrypi.com> wrote:
>
> Hi Dafna
>
> On Mon, 29 Jun 2020 at 18:01, Dafna Hirschfeld
> <dafna.hirschfeld@collabora.com> wrote:
> >
> >
> >
> > On 23.06.20 18:55, Jacopo Mondi wrote:
> > > From: Dave Stevenson <dave.stevenson@raspberrypi.com>
> > >
> > > Clients need to know the pixel rate in order to compute exposure
> > > and frame rate values. Advertise it.
> > >
> > > Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
> > > Signed-off-by: Jacopo Mondi <jacopo@jmondi.org>
> > > ---
> > >   drivers/media/i2c/ov5647.c | 40 +++++++++++++++++++++++++++++++-------
> > >   1 file changed, 33 insertions(+), 7 deletions(-)
> > >
> > > diff --git a/drivers/media/i2c/ov5647.c b/drivers/media/i2c/ov5647.c
> > > index 35865e56de5f9..218576a05e66b 100644
> > > --- a/drivers/media/i2c/ov5647.c
> > > +++ b/drivers/media/i2c/ov5647.c
> > > @@ -76,6 +76,7 @@ struct regval_list {
> > >   struct ov5647_mode {
> > >       struct v4l2_mbus_framefmt       format;
> > >       struct v4l2_rect                crop;
> > > +     u64                             pixel_rate;
> > >       struct regval_list              *reg_list;
> > >       unsigned int                    num_regs;
> > >   };
> > > @@ -97,6 +98,7 @@ struct ov5647 {
> > >       struct v4l2_ctrl_handler        ctrls;
> > >       struct ov5647_mode              *mode;
> > >       struct ov5647_mode              *current_mode;
> > > +     struct v4l2_ctrl                *pixel_rate;
> > >   };
> > >
> > >   static inline struct ov5647 *to_sensor(struct v4l2_subdev *sd)
> > > @@ -583,6 +585,7 @@ static struct ov5647_mode ov5647_sbggr8_modes[] = {
> > >                       .width          = 1280,
> > >                       .height         = 960,
> > >               },
> > > +             .pixel_rate     = 77291670,
> > >               .reg_list       = ov5647_640x480_sbggr8,
> > >               .num_regs       = ARRAY_SIZE(ov5647_640x480_sbggr8)
> > >       },
> > > @@ -604,6 +607,7 @@ static struct ov5647_mode ov5647_sbggr10_modes[] = {
> > >                       .width          = 2592,
> > >                       .height         = 1944
> > >               },
> > > +             .pixel_rate     = 87500000,
> > >               .reg_list       = ov5647_2592x1944_sbggr10,
> > >               .num_regs       = ARRAY_SIZE(ov5647_2592x1944_sbggr10)
> > >       },
> > > @@ -622,6 +626,7 @@ static struct ov5647_mode ov5647_sbggr10_modes[] = {
> > >                       .width          = 1928,
> > >                       .height         = 1080,
> > >               },
> > > +             .pixel_rate     = 81666700,
> > >               .reg_list       = ov5647_1080p30_sbggr10,
> > >               .num_regs       = ARRAY_SIZE(ov5647_1080p30_sbggr10)
> > >       },
> > > @@ -640,6 +645,7 @@ static struct ov5647_mode ov5647_sbggr10_modes[] = {
> > >                       .width          = 2592,
> > >                       .height         = 1944,
> > >               },
> > > +             .pixel_rate     = 81666700,
> > >               .reg_list       = ov5647_2x2binned_sbggr10,
> > >               .num_regs       = ARRAY_SIZE(ov5647_2x2binned_sbggr10)
> > >       },
> > > @@ -658,6 +664,7 @@ static struct ov5647_mode ov5647_sbggr10_modes[] = {
> > >                       .width          = 2560,
> > >                       .height         = 1920,
> > >               },
> > > +             .pixel_rate     = 55000000,
> > >               .reg_list       = ov5647_640x480_sbggr10,
> > >               .num_regs       = ARRAY_SIZE(ov5647_640x480_sbggr10)
> > >       },
> > > @@ -1094,6 +1101,10 @@ static int ov5647_set_pad_fmt(struct v4l2_subdev *sd,
> > >       /* Update the sensor mode and apply at it at streamon time. */
> > >       mutex_lock(&sensor->lock);
> > >       sensor->mode = mode;
> > > +
> > > +     __v4l2_ctrl_modify_range(sensor->pixel_rate, mode->pixel_rate,
> > > +                              mode->pixel_rate, 1, mode->pixel_rate);
> > > +
> > >       *fmt = mode->format;
> > >       mutex_unlock(&sensor->lock);
> > >
> > > @@ -1295,6 +1306,9 @@ static int ov5647_s_ctrl(struct v4l2_ctrl *ctrl)
> > >               return  ov5647_s_analogue_gain(sd, ctrl->val);
> > >       case V4L2_CID_EXPOSURE:
> > >               return ov5647_s_exposure(sd, ctrl->val);
> > > +     case V4L2_CID_PIXEL_RATE:
> > > +             /* Read-only, but we adjust it based on mode. */
> >
> > Looking at other drivers, I see they don't handle read only controls
> > in s_ctrl cb. Also the docs (vidioc-queryctrl.rst) says that trying to set a read only control should
> > return EINVAL
>
> It was a while ago that I looked at this, but my memory says that
> without a handler here then the call to __v4l2_ctrl_modify_range to
> update the value failed. The ranges and default were changed, but the
> current value wasn't.
>
> Checking now, yes, without returning 0 here,  __v4l2_ctrl_modify_range
> returns -22 (-EINVAL) and v4l2-ctl --list-ctrls afterwards shows
> Image Processing Controls
>
>                      pixel_rate 0x009f0902 (int64)  : min=87500000
> max=87500000 step=1 default=87500000 value=81666700 flags=read-only
>
> A failure of the framework then and needs fixing there, or is it
> correct for the driver to have to implement a set hander if it needs
> to update the ranges?
> A quick grep implies that ov5647 is the first driver that needs to
> update V4L2_CID_PIXEL_RATE based on mode. I'll check in the morning if
> things like V4L2_CID_HBLANK behave the same - it may be a control type
> issue with 64 bit values.

Just following this up, it's not a 64 bit control thing, it's any read
only control won't update the current value if you
use__v4l2_ctrl_modify_range. That's why the patch adding
V4L2_CID_HBLANK has to do the same thing.
I've just tried it on imx219 and it works fine.....

The answer is down to "modern" sensor drivers using pm_runtime having a line
    if (pm_runtime_get_if_in_use(&client->dev) == 0)
        return 0;
in their s_ctrl function. So whenever the sensor isn't streaming,
which has to be the case for setting modes, gets a 0 return value from
the s_ctrl call even though the control is invalid.
That does seem to be a failure within the ctrl core then. Effectively
other drivers do have this handling in, but via a different route.

Hans or Sakari may have ideas on how they would like to see the core
v4l2-ctrls code fixing to cover this. try_or_set_cluster is called
from too many places for me to know whether it is safe to just skip
the s_ctrl call for read only controls.

  Dave

> Interesting that the docs say EINVAL as at least one path in the
> framework appears to return -EACCES [1]
> Checking it:
> pi@raspberrypi:~ $ v4l2-ctl --set-ctrl pixel_rate=42
> VIDIOC_S_EXT_CTRLS: failed: Permission denied
> Error setting controls: Permission denied
> which would imply -EACCES
>
> I am testing on a 5.4 kernel rather than media_tree.git, but there
> don't appear to be any significant differences in this area between
> the two.
>
> Cheers.
>   Dave
>
> [1] https://git.linuxtv.org/media_tree.git/tree/drivers/media/v4l2-core/v4l2-ctrls.c#n4224
>
> > Thanks,
> > Dafna
> >
> > > +             return 0;
> > >       default:
> > >               dev_info(&client->dev,
> > >                        "Control (id:0x%x, val:0x%x) not supported\n",
> > > @@ -1313,7 +1327,7 @@ static int ov5647_init_controls(struct ov5647 *sensor)
> > >   {
> > >       struct i2c_client *client = v4l2_get_subdevdata(&sensor->sd);
> > >
> > > -     v4l2_ctrl_handler_init(&sensor->ctrls, 5);
> > > +     v4l2_ctrl_handler_init(&sensor->ctrls, 6);
> > >
> > >       v4l2_ctrl_new_std(&sensor->ctrls, &ov5647_ctrl_ops,
> > >                         V4L2_CID_AUTOGAIN, 0, 1, 1, 0);
> > > @@ -1333,17 +1347,29 @@ static int ov5647_init_controls(struct ov5647 *sensor)
> > >       v4l2_ctrl_new_std(&sensor->ctrls, &ov5647_ctrl_ops,
> > >                         V4L2_CID_ANALOGUE_GAIN, 16, 1023, 1, 32);
> > >
> > > -     if (sensor->ctrls.error) {
> > > -             dev_err(&client->dev, "%s Controls initialization failed (%d)\n",
> > > -                     __func__, sensor->ctrls.error);
> > > -             v4l2_ctrl_handler_free(&sensor->ctrls);
> > > +     /* By default, PIXEL_RATE is read only, but it does change per mode */
> > > +     sensor->pixel_rate = v4l2_ctrl_new_std(&sensor->ctrls, &ov5647_ctrl_ops,
> > > +                                            V4L2_CID_PIXEL_RATE,
> > > +                                            sensor->mode->pixel_rate,
> > > +                                            sensor->mode->pixel_rate, 1,
> > > +                                            sensor->mode->pixel_rate);
> > > +     if (!sensor->pixel_rate)
> > > +             goto handler_free;
> > > +     sensor->pixel_rate->flags |= V4L2_CTRL_FLAG_READ_ONLY;
> > >
> > > -             return sensor->ctrls.error;
> > > -     }
> > > +     if (sensor->ctrls.error)
> > > +             goto handler_free;
> > >
> > >       sensor->sd.ctrl_handler = &sensor->ctrls;
> > >
> > >       return 0;
> > > +
> > > +handler_free:
> > > +     dev_err(&client->dev, "%s Controls initialization failed (%d)\n",
> > > +             __func__, sensor->ctrls.error);
> > > +     v4l2_ctrl_handler_free(&sensor->ctrls);
> > > +
> > > +     return sensor->ctrls.error;
> > >   }
> > >
> > >   static int ov5647_parse_dt(struct ov5647 *sensor, struct device_node *np)
> > >
> > _______________________________________________
> > libcamera-devel mailing list
> > libcamera-devel@lists.libcamera.org
> > https://lists.libcamera.org/listinfo/libcamera-devel
Laurent Pinchart July 1, 2020, 7:21 a.m. UTC | #4
Hi Dave,

(Question for Hans below)

On Tue, Jun 30, 2020 at 04:13:29PM +0100, Dave Stevenson wrote:
> On Mon, 29 Jun 2020 at 22:25, Dave Stevenson wrote:
> > On Mon, 29 Jun 2020 at 18:01, Dafna Hirschfeld wrote:
> > > On 23.06.20 18:55, Jacopo Mondi wrote:
> > > > From: Dave Stevenson <dave.stevenson@raspberrypi.com>
> > > >
> > > > Clients need to know the pixel rate in order to compute exposure
> > > > and frame rate values. Advertise it.
> > > >
> > > > Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
> > > > Signed-off-by: Jacopo Mondi <jacopo@jmondi.org>
> > > > ---
> > > >   drivers/media/i2c/ov5647.c | 40 +++++++++++++++++++++++++++++++-------
> > > >   1 file changed, 33 insertions(+), 7 deletions(-)
> > > >
> > > > diff --git a/drivers/media/i2c/ov5647.c b/drivers/media/i2c/ov5647.c
> > > > index 35865e56de5f9..218576a05e66b 100644
> > > > --- a/drivers/media/i2c/ov5647.c
> > > > +++ b/drivers/media/i2c/ov5647.c
> > > > @@ -76,6 +76,7 @@ struct regval_list {
> > > >   struct ov5647_mode {
> > > >       struct v4l2_mbus_framefmt       format;
> > > >       struct v4l2_rect                crop;
> > > > +     u64                             pixel_rate;
> > > >       struct regval_list              *reg_list;
> > > >       unsigned int                    num_regs;
> > > >   };
> > > > @@ -97,6 +98,7 @@ struct ov5647 {
> > > >       struct v4l2_ctrl_handler        ctrls;
> > > >       struct ov5647_mode              *mode;
> > > >       struct ov5647_mode              *current_mode;
> > > > +     struct v4l2_ctrl                *pixel_rate;
> > > >   };
> > > >
> > > >   static inline struct ov5647 *to_sensor(struct v4l2_subdev *sd)
> > > > @@ -583,6 +585,7 @@ static struct ov5647_mode ov5647_sbggr8_modes[] = {
> > > >                       .width          = 1280,
> > > >                       .height         = 960,
> > > >               },
> > > > +             .pixel_rate     = 77291670,
> > > >               .reg_list       = ov5647_640x480_sbggr8,
> > > >               .num_regs       = ARRAY_SIZE(ov5647_640x480_sbggr8)
> > > >       },
> > > > @@ -604,6 +607,7 @@ static struct ov5647_mode ov5647_sbggr10_modes[] = {
> > > >                       .width          = 2592,
> > > >                       .height         = 1944
> > > >               },
> > > > +             .pixel_rate     = 87500000,
> > > >               .reg_list       = ov5647_2592x1944_sbggr10,
> > > >               .num_regs       = ARRAY_SIZE(ov5647_2592x1944_sbggr10)
> > > >       },
> > > > @@ -622,6 +626,7 @@ static struct ov5647_mode ov5647_sbggr10_modes[] = {
> > > >                       .width          = 1928,
> > > >                       .height         = 1080,
> > > >               },
> > > > +             .pixel_rate     = 81666700,
> > > >               .reg_list       = ov5647_1080p30_sbggr10,
> > > >               .num_regs       = ARRAY_SIZE(ov5647_1080p30_sbggr10)
> > > >       },
> > > > @@ -640,6 +645,7 @@ static struct ov5647_mode ov5647_sbggr10_modes[] = {
> > > >                       .width          = 2592,
> > > >                       .height         = 1944,
> > > >               },
> > > > +             .pixel_rate     = 81666700,
> > > >               .reg_list       = ov5647_2x2binned_sbggr10,
> > > >               .num_regs       = ARRAY_SIZE(ov5647_2x2binned_sbggr10)
> > > >       },
> > > > @@ -658,6 +664,7 @@ static struct ov5647_mode ov5647_sbggr10_modes[] = {
> > > >                       .width          = 2560,
> > > >                       .height         = 1920,
> > > >               },
> > > > +             .pixel_rate     = 55000000,
> > > >               .reg_list       = ov5647_640x480_sbggr10,
> > > >               .num_regs       = ARRAY_SIZE(ov5647_640x480_sbggr10)
> > > >       },
> > > > @@ -1094,6 +1101,10 @@ static int ov5647_set_pad_fmt(struct v4l2_subdev *sd,
> > > >       /* Update the sensor mode and apply at it at streamon time. */
> > > >       mutex_lock(&sensor->lock);
> > > >       sensor->mode = mode;
> > > > +
> > > > +     __v4l2_ctrl_modify_range(sensor->pixel_rate, mode->pixel_rate,
> > > > +                              mode->pixel_rate, 1, mode->pixel_rate);
> > > > +
> > > >       *fmt = mode->format;
> > > >       mutex_unlock(&sensor->lock);
> > > >
> > > > @@ -1295,6 +1306,9 @@ static int ov5647_s_ctrl(struct v4l2_ctrl *ctrl)
> > > >               return  ov5647_s_analogue_gain(sd, ctrl->val);
> > > >       case V4L2_CID_EXPOSURE:
> > > >               return ov5647_s_exposure(sd, ctrl->val);
> > > > +     case V4L2_CID_PIXEL_RATE:
> > > > +             /* Read-only, but we adjust it based on mode. */
> > >
> > > Looking at other drivers, I see they don't handle read only controls
> > > in s_ctrl cb. Also the docs (vidioc-queryctrl.rst) says that trying to set a read only control should
> > > return EINVAL
> >
> > It was a while ago that I looked at this, but my memory says that
> > without a handler here then the call to __v4l2_ctrl_modify_range to
> > update the value failed. The ranges and default were changed, but the
> > current value wasn't.
> >
> > Checking now, yes, without returning 0 here,  __v4l2_ctrl_modify_range
> > returns -22 (-EINVAL) and v4l2-ctl --list-ctrls afterwards shows
> > Image Processing Controls
> >
> >                      pixel_rate 0x009f0902 (int64)  : min=87500000
> > max=87500000 step=1 default=87500000 value=81666700 flags=read-only
> >
> > A failure of the framework then and needs fixing there, or is it
> > correct for the driver to have to implement a set hander if it needs
> > to update the ranges?
> > A quick grep implies that ov5647 is the first driver that needs to
> > update V4L2_CID_PIXEL_RATE based on mode. I'll check in the morning if
> > things like V4L2_CID_HBLANK behave the same - it may be a control type
> > issue with 64 bit values.
> 
> Just following this up, it's not a 64 bit control thing, it's any read
> only control won't update the current value if you
> use__v4l2_ctrl_modify_range. That's why the patch adding
> V4L2_CID_HBLANK has to do the same thing.
> I've just tried it on imx219 and it works fine.....
> 
> The answer is down to "modern" sensor drivers using pm_runtime having a line
>     if (pm_runtime_get_if_in_use(&client->dev) == 0)
>         return 0;
> in their s_ctrl function. So whenever the sensor isn't streaming,
> which has to be the case for setting modes, gets a 0 return value from
> the s_ctrl call even though the control is invalid.
> That does seem to be a failure within the ctrl core then. Effectively
> other drivers do have this handling in, but via a different route.
> 
> Hans or Sakari may have ideas on how they would like to see the core
> v4l2-ctrls code fixing to cover this. try_or_set_cluster is called
> from too many places for me to know whether it is safe to just skip
> the s_ctrl call for read only controls.

I think the control framework shouldn't call .s_ctrl() for read-only
controls. If it's read-only the __v4l2_ctrl_modify_range() is supposed
to originate from the same driver, so any specific driver-side handling
can be handled before or after calling __v4l2_ctrl_modify_range().

A better helper function to update the value of a read-only control may
be a good idea. I may also have bypassed __v4l2_ctrl_modify_range()
completely and set the value manually in the corresponding v4l2_ctrl
instance, but I understand that this would be called a hack. I know we
would lose support for control events in that case, but for
V4L2_CID_PIXEL_RATE I don't think this is a problem. Control events are
actually annoying to use synchronously, if you want to know what other
controls have been impacted by a VIDIOC_S_CTRL call, userspace code to
handle this through control events would be a bit cumbersome.

> > Interesting that the docs say EINVAL as at least one path in the
> > framework appears to return -EACCES [1]
> > Checking it:
> > pi@raspberrypi:~ $ v4l2-ctl --set-ctrl pixel_rate=42
> > VIDIOC_S_EXT_CTRLS: failed: Permission denied
> > Error setting controls: Permission denied
> > which would imply -EACCES
> >
> > I am testing on a 5.4 kernel rather than media_tree.git, but there
> > don't appear to be any significant differences in this area between
> > the two.
> >
> > [1] https://git.linuxtv.org/media_tree.git/tree/drivers/media/v4l2-core/v4l2-ctrls.c#n4224
> >
> > > > +             return 0;
> > > >       default:
> > > >               dev_info(&client->dev,
> > > >                        "Control (id:0x%x, val:0x%x) not supported\n",
> > > > @@ -1313,7 +1327,7 @@ static int ov5647_init_controls(struct ov5647 *sensor)
> > > >   {
> > > >       struct i2c_client *client = v4l2_get_subdevdata(&sensor->sd);
> > > >
> > > > -     v4l2_ctrl_handler_init(&sensor->ctrls, 5);
> > > > +     v4l2_ctrl_handler_init(&sensor->ctrls, 6);
> > > >
> > > >       v4l2_ctrl_new_std(&sensor->ctrls, &ov5647_ctrl_ops,
> > > >                         V4L2_CID_AUTOGAIN, 0, 1, 1, 0);
> > > > @@ -1333,17 +1347,29 @@ static int ov5647_init_controls(struct ov5647 *sensor)
> > > >       v4l2_ctrl_new_std(&sensor->ctrls, &ov5647_ctrl_ops,
> > > >                         V4L2_CID_ANALOGUE_GAIN, 16, 1023, 1, 32);
> > > >
> > > > -     if (sensor->ctrls.error) {
> > > > -             dev_err(&client->dev, "%s Controls initialization failed (%d)\n",
> > > > -                     __func__, sensor->ctrls.error);
> > > > -             v4l2_ctrl_handler_free(&sensor->ctrls);
> > > > +     /* By default, PIXEL_RATE is read only, but it does change per mode */
> > > > +     sensor->pixel_rate = v4l2_ctrl_new_std(&sensor->ctrls, &ov5647_ctrl_ops,
> > > > +                                            V4L2_CID_PIXEL_RATE,
> > > > +                                            sensor->mode->pixel_rate,
> > > > +                                            sensor->mode->pixel_rate, 1,
> > > > +                                            sensor->mode->pixel_rate);
> > > > +     if (!sensor->pixel_rate)
> > > > +             goto handler_free;
> > > > +     sensor->pixel_rate->flags |= V4L2_CTRL_FLAG_READ_ONLY;
> > > >
> > > > -             return sensor->ctrls.error;
> > > > -     }
> > > > +     if (sensor->ctrls.error)
> > > > +             goto handler_free;
> > > >
> > > >       sensor->sd.ctrl_handler = &sensor->ctrls;
> > > >
> > > >       return 0;
> > > > +
> > > > +handler_free:
> > > > +     dev_err(&client->dev, "%s Controls initialization failed (%d)\n",
> > > > +             __func__, sensor->ctrls.error);
> > > > +     v4l2_ctrl_handler_free(&sensor->ctrls);
> > > > +
> > > > +     return sensor->ctrls.error;
> > > >   }
> > > >
> > > >   static int ov5647_parse_dt(struct ov5647 *sensor, struct device_node *np)

Patch

diff --git a/drivers/media/i2c/ov5647.c b/drivers/media/i2c/ov5647.c
index 35865e56de5f9..218576a05e66b 100644
--- a/drivers/media/i2c/ov5647.c
+++ b/drivers/media/i2c/ov5647.c
@@ -76,6 +76,7 @@  struct regval_list {
 struct ov5647_mode {
 	struct v4l2_mbus_framefmt	format;
 	struct v4l2_rect		crop;
+	u64				pixel_rate;
 	struct regval_list		*reg_list;
 	unsigned int			num_regs;
 };
@@ -97,6 +98,7 @@  struct ov5647 {
 	struct v4l2_ctrl_handler	ctrls;
 	struct ov5647_mode		*mode;
 	struct ov5647_mode		*current_mode;
+	struct v4l2_ctrl		*pixel_rate;
 };
 
 static inline struct ov5647 *to_sensor(struct v4l2_subdev *sd)
@@ -583,6 +585,7 @@  static struct ov5647_mode ov5647_sbggr8_modes[] = {
 			.width		= 1280,
 			.height		= 960,
 		},
+		.pixel_rate	= 77291670,
 		.reg_list	= ov5647_640x480_sbggr8,
 		.num_regs	= ARRAY_SIZE(ov5647_640x480_sbggr8)
 	},
@@ -604,6 +607,7 @@  static struct ov5647_mode ov5647_sbggr10_modes[] = {
 			.width		= 2592,
 			.height		= 1944
 		},
+		.pixel_rate	= 87500000,
 		.reg_list	= ov5647_2592x1944_sbggr10,
 		.num_regs	= ARRAY_SIZE(ov5647_2592x1944_sbggr10)
 	},
@@ -622,6 +626,7 @@  static struct ov5647_mode ov5647_sbggr10_modes[] = {
 			.width		= 1928,
 			.height		= 1080,
 		},
+		.pixel_rate	= 81666700,
 		.reg_list	= ov5647_1080p30_sbggr10,
 		.num_regs	= ARRAY_SIZE(ov5647_1080p30_sbggr10)
 	},
@@ -640,6 +645,7 @@  static struct ov5647_mode ov5647_sbggr10_modes[] = {
 			.width		= 2592,
 			.height		= 1944,
 		},
+		.pixel_rate	= 81666700,
 		.reg_list	= ov5647_2x2binned_sbggr10,
 		.num_regs	= ARRAY_SIZE(ov5647_2x2binned_sbggr10)
 	},
@@ -658,6 +664,7 @@  static struct ov5647_mode ov5647_sbggr10_modes[] = {
 			.width		= 2560,
 			.height		= 1920,
 		},
+		.pixel_rate	= 55000000,
 		.reg_list	= ov5647_640x480_sbggr10,
 		.num_regs	= ARRAY_SIZE(ov5647_640x480_sbggr10)
 	},
@@ -1094,6 +1101,10 @@  static int ov5647_set_pad_fmt(struct v4l2_subdev *sd,
 	/* Update the sensor mode and apply at it at streamon time. */
 	mutex_lock(&sensor->lock);
 	sensor->mode = mode;
+
+	__v4l2_ctrl_modify_range(sensor->pixel_rate, mode->pixel_rate,
+				 mode->pixel_rate, 1, mode->pixel_rate);
+
 	*fmt = mode->format;
 	mutex_unlock(&sensor->lock);
 
@@ -1295,6 +1306,9 @@  static int ov5647_s_ctrl(struct v4l2_ctrl *ctrl)
 		return  ov5647_s_analogue_gain(sd, ctrl->val);
 	case V4L2_CID_EXPOSURE:
 		return ov5647_s_exposure(sd, ctrl->val);
+	case V4L2_CID_PIXEL_RATE:
+		/* Read-only, but we adjust it based on mode. */
+		return 0;
 	default:
 		dev_info(&client->dev,
 			 "Control (id:0x%x, val:0x%x) not supported\n",
@@ -1313,7 +1327,7 @@  static int ov5647_init_controls(struct ov5647 *sensor)
 {
 	struct i2c_client *client = v4l2_get_subdevdata(&sensor->sd);
 
-	v4l2_ctrl_handler_init(&sensor->ctrls, 5);
+	v4l2_ctrl_handler_init(&sensor->ctrls, 6);
 
 	v4l2_ctrl_new_std(&sensor->ctrls, &ov5647_ctrl_ops,
 			  V4L2_CID_AUTOGAIN, 0, 1, 1, 0);
@@ -1333,17 +1347,29 @@  static int ov5647_init_controls(struct ov5647 *sensor)
 	v4l2_ctrl_new_std(&sensor->ctrls, &ov5647_ctrl_ops,
 			  V4L2_CID_ANALOGUE_GAIN, 16, 1023, 1, 32);
 
-	if (sensor->ctrls.error) {
-		dev_err(&client->dev, "%s Controls initialization failed (%d)\n",
-			__func__, sensor->ctrls.error);
-		v4l2_ctrl_handler_free(&sensor->ctrls);
+	/* By default, PIXEL_RATE is read only, but it does change per mode */
+	sensor->pixel_rate = v4l2_ctrl_new_std(&sensor->ctrls, &ov5647_ctrl_ops,
+					       V4L2_CID_PIXEL_RATE,
+					       sensor->mode->pixel_rate,
+					       sensor->mode->pixel_rate, 1,
+					       sensor->mode->pixel_rate);
+	if (!sensor->pixel_rate)
+		goto handler_free;
+	sensor->pixel_rate->flags |= V4L2_CTRL_FLAG_READ_ONLY;
 
-		return sensor->ctrls.error;
-	}
+	if (sensor->ctrls.error)
+		goto handler_free;
 
 	sensor->sd.ctrl_handler = &sensor->ctrls;
 
 	return 0;
+
+handler_free:
+	dev_err(&client->dev, "%s Controls initialization failed (%d)\n",
+		__func__, sensor->ctrls.error);
+	v4l2_ctrl_handler_free(&sensor->ctrls);
+
+	return sensor->ctrls.error;
 }
 
 static int ov5647_parse_dt(struct ov5647 *sensor, struct device_node *np)