On Wed, 26 Feb 2025, Luca Ceresoli <luca.ceresoli@xxxxxxxxxxx> wrote:
> The global bridges_list holding all the bridges between drm_bridge_add()
> and drm_bridge_remove() cannot be inspected via debugfs. Add a file showing
> it.
>
> To avoid code duplication, move the code printing a bridge info to a common
> function.
Going forward, please separate refactoring (extracting the function)
from the functional changes (adding the new debugfs) to independent
patches. It's just easier to review.
Anyway, I reviewed this one, so no need to roll another version.
And thanks for doing this; I believe the end result is better.
Reviewed-by: Jani Nikula <jani.nikula@xxxxxxxxx>
>
> Signed-off-by: Luca Ceresoli <luca.ceresoli@xxxxxxxxxxx>
>
> ---
>
> Changed in v8:
> - add the file in drm_bridge.c, which avois the added #if CONFIG_DEBUG_FS
> - fix incorrect (but harmless) idx increment in
> drm_bridge_debugfs_show_bridge()
>
> Changed in v7:
> - move implementation to drm_bridge.c to avoid exporting bridge_list and
> bridge_mutex
>
> This patch was added in v6.
> ---
> drivers/gpu/drm/drm_bridge.c | 72 ++++++++++++++++++++++++++++++--------------
> drivers/gpu/drm/drm_drv.c | 2 ++
> include/drm/drm_bridge.h | 1 +
> 3 files changed, 53 insertions(+), 22 deletions(-)
>
> diff --git a/drivers/gpu/drm/drm_bridge.c b/drivers/gpu/drm/drm_bridge.c
> index a6bf1a565e3c3a8d24de60448972849f6d86ba72..9c6e35d41ed54a14d5745e684a341c907ed84d6b 100644
> --- a/drivers/gpu/drm/drm_bridge.c
> +++ b/drivers/gpu/drm/drm_bridge.c
> @@ -1336,6 +1336,49 @@ struct drm_bridge *of_drm_find_bridge(struct device_node *np)
> EXPORT_SYMBOL(of_drm_find_bridge);
> #endif
>
> +static void drm_bridge_debugfs_show_bridge(struct drm_printer *p,
> + struct drm_bridge *bridge,
> + unsigned int idx)
> +{
> + drm_printf(p, "bridge[%u]: %ps\n", idx, bridge->funcs);
> + drm_printf(p, "\ttype: [%d] %s\n",
> + bridge->type,
> + drm_get_connector_type_name(bridge->type));
> +
> + if (bridge->of_node)
> + drm_printf(p, "\tOF: %pOFfc\n", bridge->of_node);
> +
> + drm_printf(p, "\tops: [0x%x]", bridge->ops);
> + if (bridge->ops & DRM_BRIDGE_OP_DETECT)
> + drm_puts(p, " detect");
> + if (bridge->ops & DRM_BRIDGE_OP_EDID)
> + drm_puts(p, " edid");
> + if (bridge->ops & DRM_BRIDGE_OP_HPD)
> + drm_puts(p, " hpd");
> + if (bridge->ops & DRM_BRIDGE_OP_MODES)
> + drm_puts(p, " modes");
> + if (bridge->ops & DRM_BRIDGE_OP_HDMI)
> + drm_puts(p, " hdmi");
> + drm_puts(p, "\n");
> +}
> +
> +static int allbridges_show(struct seq_file *m, void *data)
> +{
> + struct drm_printer p = drm_seq_file_printer(m);
> + struct drm_bridge *bridge;
> + unsigned int idx = 0;
> +
> + mutex_lock(&bridge_lock);
> +
> + list_for_each_entry(bridge, &bridge_list, list)
> + drm_bridge_debugfs_show_bridge(&p, bridge, idx++);
> +
> + mutex_unlock(&bridge_lock);
> +
> + return 0;
> +}
> +DEFINE_SHOW_ATTRIBUTE(allbridges);
> +
> static int encoder_bridges_show(struct seq_file *m, void *data)
> {
> struct drm_encoder *encoder = m->private;
> @@ -1343,33 +1386,18 @@ static int encoder_bridges_show(struct seq_file *m, void *data)
> struct drm_bridge *bridge;
> unsigned int idx = 0;
>
> - drm_for_each_bridge_in_chain(encoder, bridge) {
> - drm_printf(&p, "bridge[%u]: %ps\n", idx++, bridge->funcs);
> - drm_printf(&p, "\ttype: [%d] %s\n",
> - bridge->type,
> - drm_get_connector_type_name(bridge->type));
> -
> - if (bridge->of_node)
> - drm_printf(&p, "\tOF: %pOFfc\n", bridge->of_node);
> -
> - drm_printf(&p, "\tops: [0x%x]", bridge->ops);
> - if (bridge->ops & DRM_BRIDGE_OP_DETECT)
> - drm_puts(&p, " detect");
> - if (bridge->ops & DRM_BRIDGE_OP_EDID)
> - drm_puts(&p, " edid");
> - if (bridge->ops & DRM_BRIDGE_OP_HPD)
> - drm_puts(&p, " hpd");
> - if (bridge->ops & DRM_BRIDGE_OP_MODES)
> - drm_puts(&p, " modes");
> - if (bridge->ops & DRM_BRIDGE_OP_HDMI)
> - drm_puts(&p, " hdmi");
> - drm_puts(&p, "\n");
> - }
> + drm_for_each_bridge_in_chain(encoder, bridge)
> + drm_bridge_debugfs_show_bridge(&p, bridge, idx++);
>
> return 0;
> }
> DEFINE_SHOW_ATTRIBUTE(encoder_bridges);
>
> +void drm_bridge_debugfs_params(struct dentry *root)
> +{
> + debugfs_create_file("bridges", 0444, root, NULL, &allbridges_fops);
> +}
> +
> void drm_bridge_debugfs_encoder_params(struct dentry *root,
> struct drm_encoder *encoder)
> {
> diff --git a/drivers/gpu/drm/drm_drv.c b/drivers/gpu/drm/drm_drv.c
> index 3cf440eee8a2ab3de134d925db8f1d2ce68062b7..22e8cd0a6a37a0ac25535e9d570da25571b0b2bc 100644
> --- a/drivers/gpu/drm/drm_drv.c
> +++ b/drivers/gpu/drm/drm_drv.c
> @@ -38,6 +38,7 @@
> #include <linux/xarray.h>
>
> #include <drm/drm_accel.h>
> +#include <drm/drm_bridge.h>
> #include <drm/drm_cache.h>
> #include <drm/drm_client_event.h>
> #include <drm/drm_color_mgmt.h>
> @@ -1120,6 +1121,7 @@ static int __init drm_core_init(void)
> }
>
> drm_debugfs_root = debugfs_create_dir("dri", NULL);
> + drm_bridge_debugfs_params(drm_debugfs_root);
>
> ret = register_chrdev(DRM_MAJOR, "drm", &drm_stub_fops);
> if (ret < 0)
> diff --git a/include/drm/drm_bridge.h b/include/drm/drm_bridge.h
> index 0890acfe04b99b1ccbbff10b507cb8c2b2705e06..2a99d70865571f24db0ca75c758cfd09d3a5d459 100644
> --- a/include/drm/drm_bridge.h
> +++ b/include/drm/drm_bridge.h
> @@ -1108,6 +1108,7 @@ static inline struct drm_bridge *drmm_of_get_bridge(struct drm_device *drm,
> }
> #endif
>
> +void drm_bridge_debugfs_params(struct dentry *root);
> void drm_bridge_debugfs_encoder_params(struct dentry *root, struct drm_encoder *encoder);
>
> #endif
--
Jani Nikula, Intel
