Hi Douglas,
Thank you for the patch.
On Fri, Feb 04, 2022 at 04:13:41PM -0800, Douglas Anderson wrote:
> We'd like panels to be able to add things to debugfs underneath the
> connector's directory. Let's plumb it through. A panel will be able to
> put things in a "panel" directory under the connector's
> directory. Note that debugfs is not ABI and so it's always possible
> that the location that the panel gets for its debugfs could change in
> the future.
>
> NOTE: this currently only works if you're using a modern
> architecture. Specifically the plumbing relies on _both_
> drm_bridge_connector and drm_panel_bridge. If you're not using one or
> both of these things then things won't be plumbed through.
>
> As a side effect of this change, drm_bridges can also get callbacks to
> put stuff underneath the connector's debugfs directory. At the moment
> all bridges in the chain have their debugfs_init() called with the
> connector's root directory.
>
> Signed-off-by: Douglas Anderson <dianders@xxxxxxxxxxxx>
Reviewed-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>
> ---
>
> Changes in v2:
> - ("drm: Plumb debugfs_init through to panels") new for v2.
>
> drivers/gpu/drm/bridge/panel.c | 12 ++++++++++++
> drivers/gpu/drm/drm_bridge_connector.c | 15 +++++++++++++++
> drivers/gpu/drm/drm_debugfs.c | 3 +++
> include/drm/drm_bridge.h | 7 +++++++
> include/drm/drm_connector.h | 7 +++++++
> include/drm/drm_panel.h | 8 ++++++++
> 6 files changed, 52 insertions(+)
>
> diff --git a/drivers/gpu/drm/bridge/panel.c b/drivers/gpu/drm/bridge/panel.c
> index b32295abd9e7..5be057575183 100644
> --- a/drivers/gpu/drm/bridge/panel.c
> +++ b/drivers/gpu/drm/bridge/panel.c
> @@ -138,6 +138,17 @@ static int panel_bridge_get_modes(struct drm_bridge *bridge,
> return drm_panel_get_modes(panel_bridge->panel, connector);
> }
>
> +static void panel_bridge_debugfs_init(struct drm_bridge *bridge,
> + struct dentry *root)
> +{
> + struct panel_bridge *panel_bridge = drm_bridge_to_panel_bridge(bridge);
> + struct drm_panel *panel = panel_bridge->panel;
> +
> + root = debugfs_create_dir("panel", root);
> + if (panel->funcs->debugfs_init)
> + panel->funcs->debugfs_init(panel, root);
> +}
> +
> static const struct drm_bridge_funcs panel_bridge_bridge_funcs = {
> .attach = panel_bridge_attach,
> .detach = panel_bridge_detach,
> @@ -150,6 +161,7 @@ static const struct drm_bridge_funcs panel_bridge_bridge_funcs = {
> .atomic_duplicate_state = drm_atomic_helper_bridge_duplicate_state,
> .atomic_destroy_state = drm_atomic_helper_bridge_destroy_state,
> .atomic_get_input_bus_fmts = drm_atomic_helper_bridge_propagate_bus_fmt,
> + .debugfs_init = panel_bridge_debugfs_init,
> };
>
> /**
> diff --git a/drivers/gpu/drm/drm_bridge_connector.c b/drivers/gpu/drm/drm_bridge_connector.c
> index 791379816837..60923cdfe8e1 100644
> --- a/drivers/gpu/drm/drm_bridge_connector.c
> +++ b/drivers/gpu/drm/drm_bridge_connector.c
> @@ -216,6 +216,20 @@ static void drm_bridge_connector_destroy(struct drm_connector *connector)
> kfree(bridge_connector);
> }
>
> +static void drm_bridge_connector_debugfs_init(struct drm_connector *connector,
> + struct dentry *root)
> +{
> + struct drm_bridge_connector *bridge_connector =
> + to_drm_bridge_connector(connector);
> + struct drm_encoder *encoder = bridge_connector->encoder;
> + struct drm_bridge *bridge;
> +
> + list_for_each_entry(bridge, &encoder->bridge_chain, chain_node) {
> + if (bridge->funcs->debugfs_init)
> + bridge->funcs->debugfs_init(bridge, root);
> + }
> +}
> +
> static const struct drm_connector_funcs drm_bridge_connector_funcs = {
> .reset = drm_atomic_helper_connector_reset,
> .detect = drm_bridge_connector_detect,
> @@ -223,6 +237,7 @@ static const struct drm_connector_funcs drm_bridge_connector_funcs = {
> .destroy = drm_bridge_connector_destroy,
> .atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
> .atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
> + .debugfs_init = drm_bridge_connector_debugfs_init,
> };
>
> /* -----------------------------------------------------------------------------
> diff --git a/drivers/gpu/drm/drm_debugfs.c b/drivers/gpu/drm/drm_debugfs.c
> index b0a826489488..7f1b82dbaebb 100644
> --- a/drivers/gpu/drm/drm_debugfs.c
> +++ b/drivers/gpu/drm/drm_debugfs.c
> @@ -436,6 +436,9 @@ void drm_debugfs_connector_add(struct drm_connector *connector)
> /* vrr range */
> debugfs_create_file("vrr_range", S_IRUGO, root, connector,
> &vrr_range_fops);
> +
> + if (connector->funcs->debugfs_init)
> + connector->funcs->debugfs_init(connector, root);
> }
>
> void drm_debugfs_connector_remove(struct drm_connector *connector)
> diff --git a/include/drm/drm_bridge.h b/include/drm/drm_bridge.h
> index 061d87313fac..f27b4060faa2 100644
> --- a/include/drm/drm_bridge.h
> +++ b/include/drm/drm_bridge.h
> @@ -649,6 +649,13 @@ struct drm_bridge_funcs {
> * the DRM_BRIDGE_OP_HPD flag in their &drm_bridge->ops.
> */
> void (*hpd_disable)(struct drm_bridge *bridge);
> +
> + /**
> + * @debugfs_init:
> + *
> + * Allows bridges to create bridge-specific debugfs files.
> + */
> + void (*debugfs_init)(struct drm_bridge *bridge, struct dentry *root);
> };
>
> /**
> diff --git a/include/drm/drm_connector.h b/include/drm/drm_connector.h
> index 64cf5f88c05b..54429dde744a 100644
> --- a/include/drm/drm_connector.h
> +++ b/include/drm/drm_connector.h
> @@ -1142,6 +1142,13 @@ struct drm_connector_funcs {
> * has been received from a source outside the display driver / device.
> */
> void (*oob_hotplug_event)(struct drm_connector *connector);
> +
> + /**
> + * @debugfs_init:
> + *
> + * Allows connectors to create connector-specific debugfs files.
> + */
> + void (*debugfs_init)(struct drm_connector *connector, struct dentry *root);
> };
>
> /**
> diff --git a/include/drm/drm_panel.h b/include/drm/drm_panel.h
> index 4602f833eb51..1ba2d424a53f 100644
> --- a/include/drm/drm_panel.h
> +++ b/include/drm/drm_panel.h
> @@ -29,6 +29,7 @@
> #include <linux/list.h>
>
> struct backlight_device;
> +struct dentry;
> struct device_node;
> struct drm_connector;
> struct drm_device;
> @@ -125,6 +126,13 @@ struct drm_panel_funcs {
> */
> int (*get_timings)(struct drm_panel *panel, unsigned int num_timings,
> struct display_timing *timings);
> +
> + /**
> + * @debugfs_init:
> + *
> + * Allows panels to create panels-specific debugfs files.
> + */
> + void (*debugfs_init)(struct drm_panel *panel, struct dentry *root);
> };
>
> /**
--
Regards,
Laurent Pinchart
