From d9e74da2f1fc42926c6ace1bc47a700f88ada696 Mon Sep 17 00:00:00 2001 From: Alexander Stein Date: Tue, 21 Jun 2022 09:21:18 +0200 Subject: [PATCH] drm/panel: panel-simple: Add dev_err_probe if backlight could not be found If the backlight node is not enabled, this (silently) returns with -EPROBE_DEFER. /sys/kernel/debug/devices_deferred also shows nothing helpful: $ cat /sys/kernel/debug/devices_deferred display With this patch, there is a helpful hint: $ cat /sys/kernel/debug/devices_deferred display panel-simple: Could not find backlight Signed-off-by: Alexander Stein Signed-off-by: Sam Ravnborg Link: https://patchwork.freedesktop.org/patch/msgid/20220621072118.513346-1-alexander.stein@ew.tq-group.com --- drivers/gpu/drm/panel/panel-simple.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/panel/panel-simple.c b/drivers/gpu/drm/panel/panel-simple.c index 4f15f6d1b430..ad3434550a94 100644 --- a/drivers/gpu/drm/panel/panel-simple.c +++ b/drivers/gpu/drm/panel/panel-simple.c @@ -675,8 +675,10 @@ static int panel_simple_probe(struct device *dev, const struct panel_desc *desc) drm_panel_init(&panel->base, dev, &panel_simple_funcs, connector_type); err = drm_panel_of_backlight(&panel->base); - if (err) + if (err) { + dev_err_probe(dev, err, "Could not find backlight\n"); goto disable_pm_runtime; + } drm_panel_add(&panel->base);