[PATCH v2 3/3] drm/panel: simple: add bus-format support for panel-dpi

From: Max Krummenacher
Date: Wed May 18 2022 - 07:56:43 EST


From: Max Krummenacher <max.krummenacher@xxxxxxxxxxx>

Evaluate the device tree bus-format property to set bus_format for
a 'panel-dpi' panel. Additionally infer the bpc value from the
given bus-format.

Valid values for bus-format are found in:
<include/dt-bindings/display/dt-media-bus-format.h>

This completes the addition of panel-dpi to completely specify
a panel-simple panel from the device tree.

Signed-off-by: Max Krummenacher <max.krummenacher@xxxxxxxxxxx>

---

Changes in v2:
None

drivers/gpu/drm/panel/panel-simple.c | 43 ++++++++++++++++++++++++++++
1 file changed, 43 insertions(+)

diff --git a/drivers/gpu/drm/panel/panel-simple.c b/drivers/gpu/drm/panel/panel-simple.c
index a34f4198a534..090c60abb014 100644
--- a/drivers/gpu/drm/panel/panel-simple.c
+++ b/drivers/gpu/drm/panel/panel-simple.c
@@ -21,6 +21,7 @@
* DEALINGS IN THE SOFTWARE.
*/

+#include <dt-bindings/display/dt-media-bus-format.h>
#include <linux/delay.h>
#include <linux/gpio/consumer.h>
#include <linux/module.h>
@@ -453,6 +454,7 @@ static int panel_dpi_probe(struct device *dev,
struct panel_desc *desc;
unsigned int bus_flags;
struct videomode vm;
+ u32 bus_format;
int ret;

np = dev->of_node;
@@ -477,6 +479,47 @@ static int panel_dpi_probe(struct device *dev,
of_property_read_u32(np, "width-mm", &desc->size.width);
of_property_read_u32(np, "height-mm", &desc->size.height);

+ if (!of_property_read_u32(np, "bus-format", &bus_format)) {
+ /* infer bpc from bus-format */
+ switch (bus_format) {
+ case DT_MEDIA_BUS_FMT_RGB565_1X16:
+ desc->bus_format = MEDIA_BUS_FMT_RGB565_1X16;
+ desc->bpc = 6;
+ break;
+ case DT_MEDIA_BUS_FMT_RGB666_1X18:
+ desc->bus_format = MEDIA_BUS_FMT_RGB666_1X18;
+ desc->bpc = 6;
+ break;
+ case DT_MEDIA_BUS_FMT_RGB666_1X24_CPADHI:
+ desc->bus_format = MEDIA_BUS_FMT_RGB666_1X24_CPADHI;
+ desc->bpc = 6;
+ break;
+ case DT_MEDIA_BUS_FMT_BGR888_1X24:
+ desc->bus_format = MEDIA_BUS_FMT_BGR888_1X24;
+ desc->bpc = 8;
+ break;
+ case DT_MEDIA_BUS_FMT_GBR888_1X24:
+ desc->bus_format = MEDIA_BUS_FMT_GBR888_1X24;
+ desc->bpc = 8;
+ break;
+ case DT_MEDIA_BUS_FMT_RBG888_1X24:
+ desc->bus_format = MEDIA_BUS_FMT_RBG888_1X24;
+ desc->bpc = 8;
+ break;
+ case DT_MEDIA_BUS_FMT_RGB888_1X24:
+ desc->bus_format = MEDIA_BUS_FMT_RGB888_1X24;
+ desc->bpc = 8;
+ break;
+ case DT_MEDIA_BUS_FMT_RGB888_1X32_PADHI:
+ desc->bus_format = MEDIA_BUS_FMT_RGB888_1X32_PADHI;
+ desc->bpc = 8;
+ break;
+ default:
+ dev_err(dev, "%pOF: unknown bus-format property\n", np);
+ return -EINVAL;
+ }
+ }
+
/* Extract bus_flags from display_timing */
bus_flags = 0;
vm.flags = timing->flags;
--
2.20.1