Re: [PATCH 10/10] media: i2c: ov9282: clamp flash_duration default to its maximum

[Richard Leitner <richard.leitner@linux.dev>]

Hi Dave,

thanks for your feedback!

On Tue, Sep 15, 2026 at 04:09:13PM +0100, Dave Stevenson wrote:
> "media: i2c: ov9282: clamp flash_duration default to its maximum"
> took me a moment to parse as to be the control maximum, not the default maximum.
> "clamp flash_duration default to valid range"?

Sure. That makes sense. I will adapt the patch title accordingly in v2.

regards;rl

> 
> On Mon, 14 Sept 2026 at 20:21, Richard Leitner
> <richard.leitner@linux.dev> wrote:
> >
> > Currently the OV9282_STROBE_FRAME_SPAN_DEFAULT is always passed as default
> > to the flash_duration v4l2 control, where the maximum is dynamically
> > changed. This may lead to situations where the default is above the
> > maximum.
> >
> > Fix this by setting the maximum value as default when
> > OV9282_STROBE_FRAME_SPAN_DEFAULT is above the maximum value.
> >
> > Signed-off-by: Richard Leitner <richard.leitner@linux.dev>
> 
> With or without that changed:
> Reviewed-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
> 
> > ---
> >  drivers/media/i2c/ov9282.c | 6 +++++-
> >  1 file changed, 5 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/media/i2c/ov9282.c b/drivers/media/i2c/ov9282.c
> > index be38ecfad8c82..1c5bed85781ce 100644
> > --- a/drivers/media/i2c/ov9282.c
> > +++ b/drivers/media/i2c/ov9282.c
> > @@ -11,6 +11,7 @@
> >  #include <linux/i2c.h>
> >  #include <linux/math.h>
> >  #include <linux/math64.h>
> > +#include <linux/minmax.h>
> >  #include <linux/module.h>
> >  #include <linux/pm_runtime.h>
> >  #include <linux/regmap.h>
> > @@ -556,12 +557,15 @@ static int ov9282_update_ctrl_range_flash_duration(struct ov9282 *ov9282)
> >         u32 exposure_us = ov9282_exposure_to_us(ov9282, ov9282->exp_ctrl->val);
> >         u32 fd_max = ov9282_us_to_flash_duration(ov9282, exposure_us);
> >         u32 fd_max_us = ov9282_flash_duration_to_us(ov9282, fd_max);
> > +       u32 fd_default;
> >
> >         if (fd_max_us < exposure_us)
> >                 fd_max_us = ov9282_flash_duration_to_us(ov9282, fd_max + 1);
> >
> > +       fd_default = min_t(u32, OV9282_STROBE_FRAME_SPAN_DEFAULT, fd_max_us);
> > +
> >         return __v4l2_ctrl_modify_range(ov9282->flash_duration, 0, fd_max_us,
> > -                                       1, OV9282_STROBE_FRAME_SPAN_DEFAULT);
> > +                                       1, fd_default);
> >  }
> >
> >  /**
> >
> > --
> > 2.53.0
> >
> >