Re: [PATCHv2 2/3] drm/imx: convey the pixelclk-active and de-active flags from DT to the ipu-di driver

From: Philipp Zabel
Date: Wed May 25 2016 - 06:27:10 EST


Am Mittwoch, den 25.05.2016, 08:11 +0200 schrieb Lothar WaÃmann:
[...]
> > > @@ -81,10 +87,27 @@ static int imx_pd_connector_get_modes(struct drm_connector *connector)
> > >
> > > if (np) {
> > > struct drm_display_mode *mode = drm_mode_create(connector->dev);
> > > + struct videomode vm;
> > > + int ret;
> > >
> > > if (!mode)
> > > return -EINVAL;
> > > - of_get_drm_display_mode(np, &imxpd->mode, OF_USE_NATIVE_MODE);
> > > +
> > > + ret = of_get_videomode(np, &vm, OF_USE_NATIVE_MODE);
> > > + if (ret)
> > > + return ret;
> > > + drm_display_mode_from_videomode(&vm, &imxpd->mode);
> > > + drm_mode_debug_printmodeline(&imxpd->mode);
> > > +
> > > + if (vm.flags & DISPLAY_FLAGS_PIXDATA_POSEDGE)
> > > + imxpd->bus_flags |= DRM_BUS_FLAG_PIXDATA_POSEDGE;
> > > + if (vm.flags & DISPLAY_FLAGS_PIXDATA_NEGEDGE)
> > > + imxpd->bus_flags |= DRM_BUS_FLAG_PIXDATA_NEGEDGE;
> > > +
> > > + if (vm.flags & DISPLAY_FLAGS_DE_LOW)
> > > + imxpd->bus_flags |= DRM_BUS_FLAG_DE_LOW;
> > > + if (vm.flags & DISPLAY_FLAGS_DE_HIGH)
> > > + imxpd->bus_flags |= DRM_BUS_FLAG_DE_HIGH;
> >
> > This could be shared between ldb and parallel drivers if you extended
> > of_get_drm_display_mode to also return bus_flags, for example. The flags
> > translation could be put into a drm_bus_flags_from_videomode helper.
> >
> I had that in mind also, but hesitated to change the generic
> of_get_drm_display_mode() to implement some i.MX specific functionality.

Since the videomode obtained from DT includes both the timing and pin
polarity information, and the drm way to express these are
drm_display_mode and bus_flags, respectively, there's nothing i.MX
specific about this.

regards
Philipp