Hi Laurent,
On Wed, Dec 20, 2023 at 03:02:36PM +0200, Laurent Pinchart wrote:
> Hi Tommaso,
>
> Thank you for the patch.
>
> On Wed, Dec 20, 2023 at 01:40:23PM +0100, Tommaso Merciai wrote:
> > Actually req_fr check into alvium_s_frame_interval() is wrong.
> > In particular req_fr can't be >=max and <= min at the same time.
> > Fix this using clamp and remove dft_fr parameter from
> > alvium_get_frame_interval() not more used.
>
> The commit message should have explained why clamping is better than
> picking a default value, as that's a functional change. If you propose
> an updated commit message in a reply, I think Sakari can update the
> patch when applying the series to his tree, there's no need for a v4.
What about:
Actually req_fr check into alvium_s_frame_interval() is wrong.
In particular req_fr can't be >=max and <= min at the same time.
Fix this using clamp and remove dft_fr parameter from
alvium_get_frame_interval() not more used.
Clamp function make sure that if the setted value exceeds the limits is
replaced with min_fr/max_fr instead of setting the value readed back
from the hw.
What do you think?
Thanks & Regards,
Tommaso
>
> > Signed-off-by: Tommaso Merciai <tomm.merciai@xxxxxxxxx>
>
> Reviewed-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>
>
> > ---
> > drivers/media/i2c/alvium-csi2.c | 12 ++++--------
> > 1 file changed, 4 insertions(+), 8 deletions(-)
> >
> > diff --git a/drivers/media/i2c/alvium-csi2.c b/drivers/media/i2c/alvium-csi2.c
> > index 240bf991105e..01111a00902d 100644
> > --- a/drivers/media/i2c/alvium-csi2.c
> > +++ b/drivers/media/i2c/alvium-csi2.c
> > @@ -1171,12 +1171,10 @@ static int alvium_set_bayer_pattern(struct alvium_dev *alvium,
> > }
> >
> > static int alvium_get_frame_interval(struct alvium_dev *alvium,
> > - u64 *dft_fr, u64 *min_fr, u64 *max_fr)
> > + u64 *min_fr, u64 *max_fr)
> > {
> > int ret = 0;
> >
> > - alvium_read(alvium, REG_BCRM_ACQUISITION_FRAME_RATE_RW,
> > - dft_fr, &ret);
> > alvium_read(alvium, REG_BCRM_ACQUISITION_FRAME_RATE_MIN_R,
> > min_fr, &ret);
> > alvium_read(alvium, REG_BCRM_ACQUISITION_FRAME_RATE_MAX_R,
> > @@ -1647,7 +1645,7 @@ static int alvium_s_frame_interval(struct v4l2_subdev *sd,
> > {
> > struct alvium_dev *alvium = sd_to_alvium(sd);
> > struct device *dev = &alvium->i2c_client->dev;
> > - u64 req_fr, dft_fr, min_fr, max_fr;
> > + u64 req_fr, min_fr, max_fr;
> > struct v4l2_fract *interval;
> > int ret;
> >
> > @@ -1657,7 +1655,7 @@ static int alvium_s_frame_interval(struct v4l2_subdev *sd,
> > if (fi->interval.denominator == 0)
> > return -EINVAL;
> >
> > - ret = alvium_get_frame_interval(alvium, &dft_fr, &min_fr, &max_fr);
> > + ret = alvium_get_frame_interval(alvium, &min_fr, &max_fr);
> > if (ret) {
> > dev_err(dev, "Fail to get frame interval\n");
> > return ret;
> > @@ -1670,9 +1668,7 @@ static int alvium_s_frame_interval(struct v4l2_subdev *sd,
> >
> > req_fr = (u64)((fi->interval.denominator * USEC_PER_SEC) /
> > fi->interval.numerator);
> > -
> > - if (req_fr >= max_fr && req_fr <= min_fr)
> > - req_fr = dft_fr;
> > + req_fr = clamp(req_fr, min_fr, max_fr);
> >
> > interval = v4l2_subdev_state_get_interval(sd_state, 0);
> >
>
> --
> Regards,
>
> Laurent Pinchart
