imx8mm and does not support mipi_dsi_mode_sync_pulse mode for panels?

[olliistmeinname]

Hi,

We have just discovered the following lines in the "sec-dsim.c" mipi-dsi bus driver:

(https://source.codeaurora.org/external/imx/linux-imx/tree/drivers/gpu/drm/bridge/sec-dsim.c?h=imx_5....)

if (!(dsi->mode_flags & MIPI_DSI_MODE_VIDEO)		||
	    !((dsi->mode_flags & MIPI_DSI_MODE_VIDEO_BURST)	||
	      (dsi->mode_flags & MIPI_DSI_MODE_VIDEO_SYNC_PULSE))) {
		dev_err(dev, "unsupported dsi mode\n");
		return -EINVAL;
	}

Does this mean the imx8mm does not support sync pulse mode? Is there a hardware bug?

Thanks!

[joanxie]

Imx8mm should  support sync pule mode, but only two modes support as below:

MIPI_DSI_MODE_VIDEO + MIPI_DSI_MODE_VIDEO_BURST or MIPI_DSI_MODE_VIDEO+MIPI_DSI_MODE_VIDEO_SYNC_PULSE, current bsp adv7535 can support this mode, you can refer to that

[olliistmeinname]

To provide some more information: we have a display that works on the imx8qxp using the NWL host driver (only sync pulse mode). On the imx8mm we cannot get it to work using the new samsung-dsim-imx driver with the identical settings! Here are scope traces:

(Traces are without screen attached! Therefore, not properly terminated, we also adjusted the HSA duration and timings (HS/CLK) on imx8mm - no change)

Thanks!