It's useful to know the connector's max supported bpc for IGT testing. Expose it via a debugfs file on the connector "output_bpc". Example: cat /sys/kernel/debug/dri/0/DP-1/output_bpc V2: * Fix typo in comments (Harry) Cc: Jani Nikula <jani.nikula@xxxxxxxxxxxxxxx> Cc: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> Cc: Harry Wentland <harry.wentland@xxxxxxx> Signed-off-by: Bhanuprakash Modem <bhanuprakash.modem@xxxxxxxxx> --- drivers/gpu/drm/drm_debugfs.c | 21 +++++++++++++++++++++ 1 file changed, 21 insertions(+) diff --git a/drivers/gpu/drm/drm_debugfs.c b/drivers/gpu/drm/drm_debugfs.c index 7f1b82dbaebb..fb04b7a984de 100644 --- a/drivers/gpu/drm/drm_debugfs.c +++ b/drivers/gpu/drm/drm_debugfs.c @@ -395,6 +395,23 @@ static int vrr_range_show(struct seq_file *m, void *data) } DEFINE_SHOW_ATTRIBUTE(vrr_range); +/* + * Returns Connector's max supported bpc through debugfs file. + * Example usage: cat /sys/kernel/debug/dri/0/DP-1/output_bpc + */ +static int output_bpc_show(struct seq_file *m, void *data) +{ + struct drm_connector *connector = m->private; + + if (connector->status != connector_status_connected) + return -ENODEV; + + seq_printf(m, "Maximum: %u\n", connector->display_info.bpc); + + return 0; +} +DEFINE_SHOW_ATTRIBUTE(output_bpc); + static const struct file_operations drm_edid_fops = { .owner = THIS_MODULE, .open = edid_open, @@ -437,6 +454,10 @@ void drm_debugfs_connector_add(struct drm_connector *connector) debugfs_create_file("vrr_range", S_IRUGO, root, connector, &vrr_range_fops); + /* max bpc */ + debugfs_create_file("output_bpc", 0444, root, connector, + &output_bpc_fops); + if (connector->funcs->debugfs_init) connector->funcs->debugfs_init(connector, root); } -- 2.35.1