IMX8MM-EVK with KD055HDFIA001-C001A ili9881c driver panel

[DannyEngeringh]

Hello,

I am trying to get a KD055HDFIA001-C001A display working on the imx8mmevk board but it looks like i'm missing some horizontal pixel lines. the display has a resolution of 720x1280 and the aplications seems to use the whole display. i have a similar lcd display with the same ili9881c driver but 5" and this one is doing just fine with my kernel driver. has anyone an idea what it could be? this is my drm_panel_mode:

static const struct drm_display_mode KD055HDFIA001_mode = {
.clock = 80000, //in Khz

.hdisplay = 720,
.hsync_start = 720 + 10,
.hsync_end = 720 + 10 + 20,
.htotal = 720 + 10 + 20 + 30,

.vdisplay = 1280,
.vsync_start = 1280 + 10,
.vsync_end = 1280 + 10 + 10,
.vtotal = 1280 + 10 + 10 + 20,
.width_mm = 68,
.height_mm = 121,

.flags = DRM_MODE_FLAG_NHSYNC |
DRM_MODE_FLAG_NVSYNC,
};

honestly i don't know how to get to the adding values at sync_start/end and total. anyone who can explain it to me?

Thanks in advance.

[aaron_moreno]

Hi Danny, did you managed to make the KD055HDFIA001 panel work? I'm also writing a custom driver for the KD055HDFIA001 but I'm stuck at the probing phase, is there anything special you had to do in the DTS file?

Many thanks in advance!

[Bio_TICFSL]

Hello,

Try to decrease the Horizontal Total by amount x, then subtract one-half of x from both the Horizontal Sync Start and Horizontal Sync End values. 

Regards