simple-panel already parses display-timings, enable-gpios and a
backlight phandle from DT, which is exactly what a Linux panel-lvds
node provides. Unlike Linux's drivers/gpu/drm/panel/panel-simple.c
we have no hardcoded panel tables, so there's nothing LVDS-specific
left for a dedicated driver to do. Bring panel-lvds DTs in:
- Match "panel-lvds" in the of_device_id table.
- Read modes from a "panel-timing" subnode as a fallback when
"display-timings" isn't present. Linux's panel-lvds binding uses
the singular form; without this, the panel reports "No modes
found" and the display chain has nothing to allocate a fb for.
- Switch the power-supply lookup to regulator_get_optional() and
treat -ENODEV as "no supply". Many panel-lvds DTs omit
"power-supply" because the rail is hard-wired; the call sites
already pass NULL through safely.
Signed-off-by: Johannes Schneider <[email protected]>
---
drivers/video/simple-panel.c | 23 ++++++++++++++++++++---
1 file changed, 20 insertions(+), 3 deletions(-)
diff --git a/drivers/video/simple-panel.c b/drivers/video/simple-panel.c
index 63a032a9b8..66d519425a 100644
--- a/drivers/video/simple-panel.c
+++ b/drivers/video/simple-panel.c
@@ -112,6 +112,19 @@ static int simple_panel_get_modes(struct simple_panel
*panel, struct display_tim
return 0;
}
+ /* panel-lvds DTs put the single mode in "panel-timing", not
"display-timings" */
+ if (of_get_child_by_name(panel->dev->of_node, "panel-timing")) {
+ struct fb_videomode *mode = xzalloc(sizeof(*mode));
+
+ ret = of_get_display_timing(panel->dev->of_node,
"panel-timing", mode);
+ if (!ret) {
+ timings->modes = mode;
+ timings->num_modes = 1;
+ return 0;
+ }
+ free(mode);
+ }
+
dev_err(panel->dev, "No modes found\n");
return -ENOENT;
@@ -162,9 +175,12 @@ static int simple_panel_probe(struct device *dev)
panel->backlight_node = of_parse_phandle(node, "backlight", 0);
- panel->power = regulator_get(dev, "power");
- if (IS_ERR(panel->power))
- return dev_errp_probe(dev, panel->power, "Cannot find
regulator\n");
+ panel->power = regulator_get_optional(dev, "power");
+ if (IS_ERR(panel->power)) {
+ if (PTR_ERR(panel->power) != -ENODEV)
+ return dev_errp_probe(dev, panel->power, "power
supply\n");
+ panel->power = NULL;
+ }
ret = vpl_register(&panel->vpl);
if (ret)
@@ -175,6 +191,7 @@ static int simple_panel_probe(struct device *dev)
static struct of_device_id simple_panel_of_ids[] = {
{ .compatible = "simple-panel", },
+ { .compatible = "panel-lvds", },
{ }
};
MODULE_DEVICE_TABLE(of, simple_panel_of_ids);
--
2.43.0
