Hi Laurent,
thanks for your review and your feedback.
On 6/2/23 17:39, Laurent Pinchart wrote:
Hi Johannes,
Thank you for the patch.
On Tue, May 23, 2023 at 10:19:43AM +0200, Johannes Zink wrote:
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.
Of course one could argue that the innolux,g101ice-l01 panel should have
used the panel-lvds bindings... :-)
I would prefer to add it in the panel-simple, if ever possible, as this already
has the timing information etc. in the driver. I would probably opt to use the
panel-lvds for an entirely new LVDS display, but as the innolux,g101ice-l01 is
already supported in panel-simple, imho there should be no harm in supporting
the jeida-18 operating mode as well. Also other displays in panel-simple
_might_ benefit from supporting non-default LVDS mapping modes, though I have
not researched whether they have actual hardware support for doing so.
Signed-off-by: Johannes Zink <j.zink@xxxxxxxxxxxxxx>
---
Changes:
v1 -> v2: - fix missing unwind goto found by test robot
Reported-by: kernel test robot <lkp@xxxxxxxxx>
Reported-by: Dan Carpenter <error27@xxxxxxxxx>
Link: https://lore.kernel.org/r/202304160359.4LHmFOlU-lkp@xxxxxxxxx/
---
drivers/gpu/drm/panel/panel-simple.c | 39 +++++++++++++++++++++++++++++++++++-
1 file changed, 38 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/panel/panel-simple.c b/drivers/gpu/drm/panel/panel-simple.c
index 2a9c1a785a5c..0a35fdb49ccb 100644
--- a/drivers/gpu/drm/panel/panel-simple.c
+++ b/drivers/gpu/drm/panel/panel-simple.c
@@ -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.
@@ -559,7 +560,7 @@ static int panel_simple_probe(struct device *dev, const struct panel_desc *desc)
struct device_node *ddc;
int connector_type;
u32 bus_flags;
- int err;
+ int err, ret;
panel = devm_kzalloc(dev, sizeof(*panel), GFP_KERNEL);
if (!panel)
@@ -605,6 +606,42 @@ static int panel_simple_probe(struct device *dev, const struct panel_desc *desc)
panel_simple_parse_panel_timing_node(dev, panel, &dt);
}
+
Double blank line.
ack, gonna fix in v3.
+ /* optional data-mapping property for overriding bus format */
s/optional/Optional/
ack, gonna fix in v3.
+ ret = drm_of_lvds_get_data_mapping(dev->of_node);
+ if (ret == -EINVAL) {
+ dev_warn(dev, "Ignore invalid data-mapping property");
+ } else if (ret != -ENODEV) {
If someone incorrectly sets the property in DT for a non-LVDS panel,
the result won't be nice. That's of course a DT issue, but I wonder if
we could/should protect against it. You could move this code to a
separate function (which would have the added benefit of lowering the
indentation level as you can return early in error cases), and call it
from panel_simple_probe() only if the panel is an LVDS panel (as
reported by its desc->bus_format value).
that's a good idea, gonna change it for v3.
+ int bpc;
+
+ 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 (desc->bpc != bpc || desc->bus_format != ret) {
+ struct panel_desc *override_desc;
+
+ override_desc = devm_kmemdup(dev, desc, sizeof(*desc), GFP_KERNEL);
+ if (!override_desc) {
+ err = -ENOMEM;
+ goto free_ddc;
+ }
+
+ override_desc->bus_format = ret;
+ override_desc->bpc = bpc;
+ panel->desc = override_desc;
+ }
+ }
+
connector_type = desc->connector_type;
/* Catch common mistakes for panels. */
switch (connector_type) {
--
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31137 Hildesheim, Germany | Phone: +49-5121-206917-0 |
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