We are trying to drive a RGB565 mipi display
Another RGB888 display is working fine
dsi->format = MIPI_DSI_FMT_RGB888;
But for RGB565
dsi->format = MIPI_DSI_FMT_RGB565;
we can't to get it working correct.
When measuring the mipi lane, we see that a line lenght is shorter for RGB565 then RGB888. So it seems that the RGB565 is taken.
But when filling the framebuffer with 0xFF, and measuring the data lane, we something like 0xFC so a few bits are put to zero.
In logging we see lcdif_set_pix_fmt being called with DRM_FORMAT_XRGB8888. And looking at the code, we think the conversion form 888 to 565 should be ok.
/* bpp 32 */
case DRM_FORMAT_ARGB8888:
case DRM_FORMAT_XRGB8888:
case DRM_FORMAT_ABGR8888:
case DRM_FORMAT_XBGR8888:
case DRM_FORMAT_RGBA8888:
case DRM_FORMAT_RGBX8888:
/*Data format */
printk(KERN_WARNING "%s DRM_FORMAT_ARGB8888\n", __func__);
ctrl &= ~CTRL_DF24;
ctrl |= CTRL_SET_WORD_LENGTH(3);
if (format == DRM_FORMAT_RGBA8888 ||
format == DRM_FORMAT_RGBX8888)
ctrl |= CTRL_SHIFT_DIR(1) | CTRL_SHIFT_NUM(8);
/* Byte packing */
ctrl1 |= CTRL1_SET_BYTE_PACKAGING(0x7);
/* 'BGR' order */
if (format == DRM_FORMAT_ABGR8888 ||
format == DRM_FORMAT_XBGR8888)
writel(CTRL2_ODD_LINE_PATTERN(0x5) |
CTRL2_EVEN_LINE_PATTERN(0x5),
lcdif->base + LCDIF_CTRL2 + REG_SET);
break;
Any pointers would be great
