On Mon, Feb 27, 2023 at 11:17 PM Maxime Ripard <maxime@xxxxxxxxxx> wrote: > > On Mon, Feb 27, 2023 at 11:02:30PM +0530, Jagan Teki wrote: > > drmm_panel_bridge_add_nodrm is an another type of DRM-managed action > > helper with nodrm pointer. > > > > DRM pointer is required to perform DRM-managed action, > > - The conventional component-based drm bridges, the DRM pointer can > > access in component ops bind API. > > - The non-component-based bridges (like host DSI bridges), the DRM > > pointer can access only when a specific bridge has been found > > via bridge->dev. > > > > This drmm_panel_bridge_add_nodrm helper exclusively for the > > non-component-based bridges. > > > > Cc: Maxime Ripard <mripard@xxxxxxxxxx> > > Cc: Laurent Pinchart <Laurent.pinchart@xxxxxxxxxxxxxxxx> > > Cc: Linus Walleij <linus.walleij@xxxxxxxxxx> > > Cc: Maarten Lankhorst <maarten.lankhorst@xxxxxxxxxxxxxxx> > > Signed-off-by: Jagan Teki <jagan@xxxxxxxxxxxxxxxxxxxx> > > It's the third or fourth time I'm telling you this, and second time > today. Apologies for this. > > You keep respinning that patch, but the issue lies in the samsung > driver. Fix it and you won't need that helper. This is where all get' stuck. You mentioned in a previous e-mail was, "I'm not quite sure what you mean. You shouldn't retrieve the bridge from the attach hook but from the probe / bind ones. If that's not working for you, this is a bug in the documentation we should address." If I understand correctly this would be the third case from the bridge documentation https://dri.freedesktop.org/docs/drm/gpu/drm-kms-helpers.html#special-care-with-mipi-dsi-bridges "The upstream driver uses the component framework and is a MIPI-DSI host. The bridge device uses the MIPI-DCS commands to be controlled. This is the same situation as above, and can run mipi_dsi_host_register() in either its probe or bind hooks." But the problem here, The samsung-dsim bridge common bridge across Exynos and i.MX8MM. So, the - Upstream Exynos is component-based and - Upstream i.MX8MM is non-component-based With this dual scenario, retrieving the bridge pointer in a bind will work for the Exynos case, and retrieving the bridge pointer in bridge. attach will work for i.MX8MM. This is what I mentioned deadlock scenario in a previous e-mail. Hope you clear the real issue now. Thanks, Jagan.
