Hi Jacopo,
On Fri, May 17, 2024 at 12:17:35PM +0200, Jacopo Mondi wrote:
> Hi Sakari
>
> On Thu, May 16, 2024 at 03:25:36PM GMT, Sakari Ailus wrote:
> > v4l2_get_link_freq() accepts a V4L2 control handler for now, but it needs
> > to take struct media_pad argument in order to obtain the link frequency
> > using get_mbus_config() pad op. Prepare for this by allowing struct
> > media_pad as well.
> >
> > Signed-off-by: Sakari Ailus <sakari.ailus@xxxxxxxxxxxxxxx>
> > ---
> > drivers/media/v4l2-core/v4l2-common.c | 21 ++++++++++++++++++---
> > include/media/v4l2-common.h | 19 ++++++++++++++++---
> > 2 files changed, 34 insertions(+), 6 deletions(-)
> >
> > diff --git a/drivers/media/v4l2-core/v4l2-common.c b/drivers/media/v4l2-core/v4l2-common.c
> > index 4165c815faef..01650aed7c30 100644
> > --- a/drivers/media/v4l2-core/v4l2-common.c
> > +++ b/drivers/media/v4l2-core/v4l2-common.c
> > @@ -464,8 +464,8 @@ int v4l2_fill_pixfmt(struct v4l2_pix_format *pixfmt, u32 pixelformat,
> > }
> > EXPORT_SYMBOL_GPL(v4l2_fill_pixfmt);
> >
> > -s64 v4l2_get_link_freq(struct v4l2_ctrl_handler *handler, unsigned int mul,
> > - unsigned int div)
> > +s64 __v4l2_get_link_freq_ctrl(struct v4l2_ctrl_handler *handler,
> > + unsigned int mul, unsigned int div)
> > {
> > struct v4l2_ctrl *ctrl;
> > s64 freq;
> > @@ -500,7 +500,22 @@ s64 v4l2_get_link_freq(struct v4l2_ctrl_handler *handler, unsigned int mul,
> >
> > return freq > 0 ? freq : -EINVAL;
> > }
> > -EXPORT_SYMBOL_GPL(v4l2_get_link_freq);
> > +EXPORT_SYMBOL_GPL(__v4l2_get_link_freq_ctrl);
> > +
> > +#ifdef CONFIG_MEDIA_CONTROLLER
> > +s64 __v4l2_get_link_freq_pad(struct media_pad *pad, unsigned int mul,
> > + unsigned int div)
> > +{
> > + struct v4l2_subdev *sd;
> > +
> > + sd = media_entity_to_v4l2_subdev(pad->entity);
> > + if (!sd)
> > + return -ENODEV;
> > +
> > + return __v4l2_get_link_freq_ctrl(sd->ctrl_handler, mul, div);
> > +}
> > +EXPORT_SYMBOL_GPL(__v4l2_get_link_freq_pad);
> > +#endif /* CONFIG_MEDIA_CONTROLLER */
> >
> > /*
> > * Simplify a fraction using a simple continued fraction decomposition. The
> > diff --git a/include/media/v4l2-common.h b/include/media/v4l2-common.h
> > index 63ad36f04f72..f29dc8bb8f09 100644
> > --- a/include/media/v4l2-common.h
> > +++ b/include/media/v4l2-common.h
> > @@ -525,7 +525,8 @@ int v4l2_fill_pixfmt_mp(struct v4l2_pix_format_mplane *pixfmt, u32 pixelformat,
> > /**
> > * v4l2_get_link_freq - Get link rate from transmitter
> > *
> > - * @handler: The transmitter's control handler
> > + * @pad: The transmitter's media pad (or control handler for non-MC users or
>
> The users of get_link_freq we have in mainline all select
> MEDIA_CONTROLLER if I checked correctly
> v4l2_get_link_freq
>
> drivers/media/i2c/st-mipid02.c
> drivers/media/i2c/tc358746.c
> drivers/media/pci/intel/ipu3/ipu3-cio2.c
> drivers/media/pci/intel/ipu6/ipu6-isys-csi2.c
> drivers/media/pci/intel/ivsc/mei_csi.c
> drivers/media/platform/cadence/cdns-csi2rx.c
> drivers/media/platform/nxp/imx-mipi-csis.c
> drivers/media/platform/nxp/imx8mq-mipi-csi2.c
> drivers/media/platform/qcom/camss/camss.c
> drivers/media/platform/ti/cal/cal-camerarx.c
>
> is it even worth having a compatibility fallback or can they be
> switched to use the remote's pad ?
Good question. Now that we have this patch, I'd merge it and remove the
non-pad variant after all drivers have been converted. I can do the
conversion soonish.
>
>
> > + * compatibility reasons, don't use in new code)
> > * @mul: The multiplier between pixel rate and link frequency. Bits per pixel on
> > * D-PHY, samples per clock on parallel. 0 otherwise.
> > * @div: The divisor between pixel rate and link frequency. Number of data lanes
> > @@ -541,8 +542,20 @@ int v4l2_fill_pixfmt_mp(struct v4l2_pix_format_mplane *pixfmt, u32 pixelformat,
> > * * %-ENOENT: Link frequency or pixel rate control not found
> > * * %-EINVAL: Invalid link frequency value
> > */
> > -s64 v4l2_get_link_freq(struct v4l2_ctrl_handler *handler, unsigned int mul,
> > - unsigned int div);
> > +#ifdef CONFIG_MEDIA_CONTROLLER
> > +#define v4l2_get_link_freq(pad, mul, div) \
> > + _Generic(pad, \
> > + struct media_pad *: __v4l2_get_link_freq_pad, \
> > + struct v4l2_ctrl_handler *: __v4l2_get_link_freq_ctrl) \
> > + (pad, mul, div)
> > +s64 __v4l2_get_link_freq_pad(struct media_pad *pad, unsigned int mul,
> > + unsigned int div);
> > +#else /* !CONFIG_MEDIA_CONTROLLER */
> > +#define v4l2_get_link_freq(handler, mul, div) \
> > + __v4l2_get_link_freq_ctrl(handler, mul, div)
> > +#endif /* !CONFIG_MEDIA_CONTROLLER */
>
> nit: no ! in !CONFIG_MEDIA_CONTROLLER
I can also remove the comments, these sections are short enough so it's not
very useful.
> nit: maybe an empty line here ?
It's very much related to what's above, I'd prefer it this way but I don't
have a strong opinion about it either. :-)
>
> > +s64 __v4l2_get_link_freq_ctrl(struct v4l2_ctrl_handler *handler,
> > + unsigned int mul, unsigned int div);
> >
> > void v4l2_simplify_fraction(u32 *numerator, u32 *denominator,
> > unsigned int n_terms, unsigned int threshold);
--
Regards,
Sakari Ailus
