On Mon, Feb 27, 2023 at 05:58:03PM +0530, Jagan Teki wrote: > On Mon, Feb 27, 2023 at 5:41 PM Maxime Ripard <maxime@xxxxxxxxxx> wrote: > > > > On Mon, Feb 27, 2023 at 05:09:09PM +0530, Jagan Teki wrote: > > > drmm_panel_bridge_add DRM-managed action helper is useful for the bridge > > > which automatically removes the bridge when drm pointer is cleaned. > > > > > > Supporting the same on non-component bridges like host DSI bridge requires > > > a drm pointer which is indeed available only when a panel-bridge is found. > > > > > > For these use cases, the caller would call the drmm_panel_bridge_add by > > > passing NULL to drm pointer. > > > > > > So, assign the bridge->dev to drm pointer for those cases. > > > > > > 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> > > > --- > > > Changes for v13: > > > - new patch > > > > > > Note: use case on > > > "[PATCH v13 04/18] drm: exynos: dsi: Switch to DSI panel or bridge find helper" > > > > > > drivers/gpu/drm/bridge/panel.c | 7 +++++++ > > > 1 file changed, 7 insertions(+) > > > > > > diff --git a/drivers/gpu/drm/bridge/panel.c b/drivers/gpu/drm/bridge/panel.c > > > index d4b112911a99..45a0c6671000 100644 > > > --- a/drivers/gpu/drm/bridge/panel.c > > > +++ b/drivers/gpu/drm/bridge/panel.c > > > @@ -402,6 +402,13 @@ struct drm_bridge *drmm_panel_bridge_add(struct drm_device *drm, > > > if (IS_ERR(bridge)) > > > return bridge; > > > > > > + /* > > > + * For non-component bridges, like host DSI bridge the DRM pointer > > > + * can be available only when a panel-bridge is found. > > > + */ > > > + if (!drm) > > > + drm = bridge->dev; > > > + > > > > Why can't the caller use bridge->dev? > > The first step of drmm_panel_bridge_add is to find the panel-bridge, > so we can only get bridge->dev after this step. The caller doesn't > know anything about the panel bridge it just sends a panel pointer to > find the panel-bridge Ah, yes, indeed. This is still a hack we don't need. > then assigns bridge->dev to drm for DRM action > > Please check this patch about the caller, > https://patchwork.kernel.org/project/dri-devel/patch/20230227113925.875425-5-jagan@xxxxxxxxxxxxxxxxxxxx/ Because we've already been over this. You can't call that function from DSI's attach. So you should change that to what I already pointed you to, and then you'll have the drm device pointer available. > > Also, where did the devm_drm_of_dsi_get_bridge go? I thought you were > > going to convert it to a drm-managed version? > > Look like your suggestion to can't use devm_drm_of_dsi_get_bridge and > call the DRM-action from the driver, that is the reason I have removed > this and done the same as your previous inputs. > https://lore.kernel.org/all/20230203110437.otzl2azscbujigv6@houat/ You can't use devm. You can and should definitely use drmm. Maxime
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