Re: [PATCH] drm: dw-hdmi: Implement the mode_fixup drm helper

[Archit Taneja]

On 04/08/2017 12:03 AM, Daniel Vetter wrote:
> On Fri, Apr 07, 2017 at 02:17:43PM +0200, Romain Perier wrote:
> > This helper is supposed to validate or reject the modeline before it
> > applied by the mode setting. Currently this function has been dropped,
> > it was previously set to a dummy function that always returned true. For
> > both cases, this means that userspace can ask for a bad modeline that
> > will be always accepted.
> >
> > On some platforms, like Rockchip, the drm dw_hdmi-rockchip variant driver
> > already implements the atomic_check drm helper, so mode_fixup cannot be
> > handled and implemented there (as drm_atomic_helper relies on either
> > atomic_check or mode_fixup).
> >
> > This commit implements this helper. It only checks that this mode is
> > correct from the connector point of view
> >
> > Signed-off-by: Romain Perier <romain.perier@xxxxxxxxxxxxx>	
>
> Yup this is how it's supposed to be done, check bridge limits in the
> bridge's mode_fixup hook.
>
> Acked-by: Daniel Vetter <daniel.vetter@xxxxxxxx>

queued to drm-misc-next-fixes (so that it makes it into 4.12).

Thanks,
Archit

> > ---
> >  drivers/gpu/drm/bridge/dw-hdmi.c | 16 ++++++++++++++++
> >  1 file changed, 16 insertions(+)
> >
> > diff --git a/drivers/gpu/drm/bridge/dw-hdmi.c b/drivers/gpu/drm/bridge/dw-hdmi.c
> > index 22211ff..3bd0807 100644
> > --- a/drivers/gpu/drm/bridge/dw-hdmi.c
> > +++ b/drivers/gpu/drm/bridge/dw-hdmi.c
> > @@ -1740,6 +1740,21 @@ static int dw_hdmi_bridge_attach(struct drm_bridge *bridge)
> >  	return 0;
> >  }
> >
> > +
> > +static bool dw_hdmi_bridge_mode_fixup(struct drm_bridge *bridge,
> > +				      const struct drm_display_mode *orig_mode,
> > +				      struct drm_display_mode *mode)
> > +{
> > +	struct dw_hdmi *hdmi = bridge->driver_private;
> > +	struct drm_connector *connector = &hdmi->connector;
> > +	enum drm_mode_status status;
> > +
> > +	status = dw_hdmi_connector_mode_valid(connector, mode);
> > +	if (status != MODE_OK)
> > +		return false;
> > +	return true;
> > +}
> > +
> >  static void dw_hdmi_bridge_mode_set(struct drm_bridge *bridge,
> >  				    struct drm_display_mode *orig_mode,
> >  				    struct drm_display_mode *mode)
> > @@ -1781,6 +1796,7 @@ static const struct drm_bridge_funcs dw_hdmi_bridge_funcs = {
> >  	.enable = dw_hdmi_bridge_enable,
> >  	.disable = dw_hdmi_bridge_disable,
> >  	.mode_set = dw_hdmi_bridge_mode_set,
> > +	.mode_fixup = dw_hdmi_bridge_mode_fixup,
> >  };
> >
> >  static irqreturn_t dw_hdmi_i2c_irq(struct dw_hdmi *hdmi)
> > --
> > 2.9.3
> >
> > _______________________________________________
> > dri-devel mailing list
> > dri-devel@xxxxxxxxxxxxxxxxxxxxx
> > https://lists.freedesktop.org/mailman/listinfo/dri-devel

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