Hey Andrzej, Andrzej Hajda wrote: > On 21.09.2016 00:07, Tobias Jakobi wrote: >> Hello, >> >> I'm currently facing the following problem. >> >> I want to use a devfreq device in one of the Exynos sub drivers, namely >> the G2D sub driver. My current approach is to use >> devfreq_get_devfreq_by_phandle() in g2d_probe(). But at the G2D probing >> time the devfreq subsystem isn't initialized yet, and I get EPROBE_DEFER >> back. >> >> Now I simply let g2d_probe() fail with EPROBE_DEFER in that case. >> Eventually devfreq is online and g2d_probe() runs successfully. >> >> So far, so good. However some debugging shows that g2d_subdrv_probe(), >> which does IOMMU setup and allocates the cmdlist, never happens in that >> case. >> >> I've looked at exynos_drm_load() which issues >> exynos_drm_device_subdrv_probe() at some point, which apparantly only >> probes those devices which are registered at that time. Hence, if the >> G2D probe hasn't happened until then, the Exynos DRM won't ever see it. >> >> That made me wonder how the driver makes sure that the sub drivers are >> all readily probed in that situation. I see that a component_bind_all() >> is issued prior to subdrv probing, but both the G2D and the IPP subdrv >> don't have bind/unbind calls. I guess subdrv != subdrv, eh? >> >> At present it appears that it's merely luck that the G2D is probed when >> sub drivers are probed? >> >> Anyway, probe deferral seems to work correctly with Exynos HDMI, so I >> was wondering if there is some way to also make it work with the G2D? > > HDMI is componentized, G2D no, so it does not work with deferred probe. > The best solution at the moment is to componentize G2D, it should > not be difficult. I see! I try to look into this, but probably I'm going to ask for help again. If that's OK with you? ;-) With best wishes, Tobias > > Regards > Andrzej > >> >> Thanks in advance! >> >> With best wishes, >> Tobias >> _______________________________________________ >> dri-devel mailing list >> dri-devel@xxxxxxxxxxxxxxxxxxxxx >> https://lists.freedesktop.org/mailman/listinfo/dri-devel > > -- To unsubscribe from this list: send the line "unsubscribe linux-samsung-soc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
 |