On 12/05/2024 17:25, Noralf Trønnes via B4 Relay wrote:
From: Noralf Trønnes <noralf@xxxxxxxxxxx>
Add support for these pixel format property values:
- r5g6b5, RGB565
- b6x2g6x2r6x2, BGR666
BGR666 is presented to userspace as RGB888. The 2 LSB in each color
are discarded by the controller. The pixel is sent on the wire using
8 bits per word (little endian) so the controller sees it as BGR.
RGB565 is the default if the property is not present.
Signed-off-by: Noralf Trønnes <noralf@xxxxxxxxxxx>
---
drivers/gpu/drm/tiny/panel-mipi-dbi.c | 55 ++++++++++++++++++++++++++++++++++-
1 file changed, 54 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/tiny/panel-mipi-dbi.c b/drivers/gpu/drm/tiny/panel-mipi-dbi.c
index f80a141fcf36..f3aa2abce314 100644
--- a/drivers/gpu/drm/tiny/panel-mipi-dbi.c
+++ b/drivers/gpu/drm/tiny/panel-mipi-dbi.c
@@ -26,6 +26,49 @@
#include <video/mipi_display.h>
+struct panel_mipi_dbi_format {
+ const char *name;
+ u32 fourcc;
+ unsigned int bpp;
+};
+
+static const struct panel_mipi_dbi_format panel_mipi_dbi_formats[] = {
+ { "r5g6b5", DRM_FORMAT_RGB565, 16 },
+ { "b6x2g6x2r6x2", DRM_FORMAT_RGB888, 24 },
+};
+
+static int panel_mipi_dbi_get_format(struct device *dev, u32 *formats, unsigned int *bpp)
+{
+ const char *format_name;
+ unsigned int i;
+ int ret;
+
+ formats[1] = DRM_FORMAT_XRGB8888;
+
+ ret = device_property_read_string(dev, "format", &format_name);
+ if (ret) {
+ /* Old Device Trees don't have this property */
+ formats[0] = DRM_FORMAT_RGB565;
+ *bpp = 16;
+ return 0;
+ }
+
+ for (i = 0; i < ARRAY_SIZE(panel_mipi_dbi_formats); i++) {
+ const struct panel_mipi_dbi_format *format = &panel_mipi_dbi_formats[i];
+
+ if (strcmp(format_name, format->name))
+ continue;
+
+ formats[0] = format->fourcc;
+ *bpp = format->bpp;
+ return 0;
+ }
+
+ dev_err(dev, "Pixel format is not supported: '%s'\n", format_name);
+
+ return -EINVAL;
+}
+
static const u8 panel_mipi_dbi_magic[15] = { 'M', 'I', 'P', 'I', ' ', 'D', 'B', 'I',
0, 0, 0, 0, 0, 0, 0 };
@@ -276,6 +319,9 @@ static int panel_mipi_dbi_spi_probe(struct spi_device *spi)
struct drm_device *drm;
struct mipi_dbi *dbi;
struct gpio_desc *dc;
+ unsigned int bpp;
+ size_t buf_size;
+ u32 formats[2];
int ret;
dbidev = devm_drm_dev_alloc(dev, &panel_mipi_dbi_driver, struct mipi_dbi_dev, drm);
@@ -323,7 +369,14 @@ static int panel_mipi_dbi_spi_probe(struct spi_device *spi)
if (IS_ERR(dbidev->driver_private))
return PTR_ERR(dbidev->driver_private);
- ret = mipi_dbi_dev_init(dbidev, &panel_mipi_dbi_pipe_funcs, &mode, 0);
+ ret = panel_mipi_dbi_get_format(dev, formats, &bpp);
+ if (ret)
+ return ret;
+
+ buf_size = DIV_ROUND_UP(mode.hdisplay * mode.vdisplay * bpp, 8);
+ ret = mipi_dbi_dev_init_with_formats(dbidev, &panel_mipi_dbi_pipe_funcs,
+ formats, ARRAY_SIZE(formats),
+ &mode, 0, buf_size);
if (ret)
return ret;
Reviewed-by: Neil Armstrong <neil.armstrong@xxxxxxxxxx>
