drm/panel-simple: allow LVDS format override

Some panels support multiple LVDS data mapping formats, which can be
used e.g. run displays on jeida-18 format when only 3 LVDS lanes are
available.

Add parsing of an optional data-mapping devicetree property, which also
touches up the bits per color to match the bus format.

Signed-off-by: Johannes Zink <j.zink@pengutronix.de>
Link: https://lore.kernel.org/r/20230523-simplepanel_support_nondefault_datamapping-v5-3-0d7928edafab@pengutronix.de
Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20230523-simplepanel_support_nondefault_datamapping-v5-3-0d7928edafab@pengutronix.de
This commit is contained in:
Johannes Zink 2023-09-29 14:33:33 +02:00 committed by Neil Armstrong
parent 66b66c97f4
commit 1cd3ea3e4b
1 changed files with 53 additions and 0 deletions

View File

@ -40,6 +40,7 @@
#include <drm/drm_edid.h>
#include <drm/drm_mipi_dsi.h>
#include <drm/drm_panel.h>
#include <drm/drm_of.h>
/**
* struct panel_desc - Describes a simple panel.
@ -549,6 +550,51 @@ static void panel_simple_parse_panel_timing_node(struct device *dev,
dev_err(dev, "Reject override mode: No display_timing found\n");
}
static int panel_simple_override_nondefault_lvds_datamapping(struct device *dev,
struct panel_simple *panel)
{
int ret, bpc;
ret = drm_of_lvds_get_data_mapping(dev->of_node);
if (ret < 0) {
if (ret == -EINVAL)
dev_warn(dev, "Ignore invalid data-mapping property\n");
/*
* Ignore non-existing or malformatted property, fallback to
* default data-mapping, and return 0.
*/
return 0;
}
switch (ret) {
default:
WARN_ON(1);
fallthrough;
case MEDIA_BUS_FMT_RGB888_1X7X4_SPWG:
fallthrough;
case MEDIA_BUS_FMT_RGB888_1X7X4_JEIDA:
bpc = 8;
break;
case MEDIA_BUS_FMT_RGB666_1X7X3_SPWG:
bpc = 6;
}
if (panel->desc->bpc != bpc || panel->desc->bus_format != ret) {
struct panel_desc *override_desc;
override_desc = devm_kmemdup(dev, panel->desc, sizeof(*panel->desc), GFP_KERNEL);
if (!override_desc)
return -ENOMEM;
override_desc->bus_format = ret;
override_desc->bpc = bpc;
panel->desc = override_desc;
}
return 0;
}
static int panel_simple_probe(struct device *dev, const struct panel_desc *desc)
{
struct panel_simple *panel;
@ -601,6 +647,13 @@ static int panel_simple_probe(struct device *dev, const struct panel_desc *desc)
panel_simple_parse_panel_timing_node(dev, panel, &dt);
}
if (desc->connector_type == DRM_MODE_CONNECTOR_LVDS) {
/* Optional data-mapping property for overriding bus format */
err = panel_simple_override_nondefault_lvds_datamapping(dev, panel);
if (err)
goto free_ddc;
}
connector_type = desc->connector_type;
/* Catch common mistakes for panels. */
switch (connector_type) {