i.mx 8m mini: How to skip panel-init-squence when there is no panel

[ko1596]

This is my kernel version

Linux version 4.14.98-imx_4.14.98_2.0.0

I'm using a mipi panel

If I don't connect the panel, the kernel prints some dsi send timeout messages

like this

Spoiler

[ 1.862508] [LVDS Sequence] 1 Start to enable LVDS VDD.
[ 1.862515] [LVDS Sequence] 2 Start to enable LVDS signal.
[ 2.134706] imx_sec_dsim_drv 32e10000.mipi_dsi: wait pkthdr tx done time out
[ 2.134712] panel-simple-dsi 32e10000.mipi_dsi.0: failed to write dcs cmd: -16
[ 2.390701] imx_sec_dsim_drv 32e10000.mipi_dsi: wait pkthdr tx done time out
.....
[ 41.046704] panel-simple-dsi 32e10000.mipi_dsi.0: failed to write dcs cmd: -16
[ 41.090150] Console: switching to colour frame buffer device 96x64
[ 41.336674] [LVDS Sequence] 4 Start to enable backlight PWM.
[ 41.357698] [LVDS Sequence] 5 Start to enable LVDS backlight.
[ 43.556766] imx-drm display-subsystem: fb0: frame buffer device
[ 43.563068] [drm] Initialized imx-drm 1.0.0 20120507 for display-subsystem on minor 0
[ 43.575427] loop: module loaded

The following are normal

Spoiler

[ 1.807996] [drm] Supports vblank timestamp caching Rev 2 (21.10.2013).
[ 1.814694] [drm] No driver support for vblank timestamp query.
[ 1.820722] imx-drm display-subsystem: bound imx-lcdif-crtc.0 (ops lcdif_crtc_ops)
[ 1.828393] imx_sec_dsim_drv 32e10000.mipi_dsi: version number is 0x1060200
[ 1.835529] panel-simple-dsi 32e10000.mipi_dsi.0: 32e10000.mipi_dsi.0 supply power not found, using dummy regulator
[ 1.846049] panel-simple-dsi 32e10000.mipi_dsi.0: panel_simple_dsi_parse_dcs_cmds: dcs_cmd=39 len=1040, cmd_cnt=207
[ 1.856560] imx-drm display-subsystem: bound 32e10000.mipi_dsi (ops imx_sec_dsim_ops)
[ 1.864425] panel@0: no display-panel specified
[ 1.872455] [LVDS Sequence] 1 Start to enable LVDS VDD.
[ 1.872462] [LVDS Sequence] 2 Start to enable LVDS signal.
[ 2.176016] Console: switching to colour frame buffer device 96x64
[ 2.422549] [LVDS Sequence] 4 Start to enable backlight PWM.
[ 2.443574] [LVDS Sequence] 5 Start to enable LVDS backlight.
[ 2.471911] imx-drm display-subsystem: fb0: frame buffer device
[ 2.478207] [drm] Initialized imx-drm 1.0.0 20120507 for display-subsystem on minor 0

How can I fix it

I want to skip the panel detection when not using the panel

Or how can I not send panel-init-squence

[Zhiming_Liu]

Please try to add dsi->mode_flags |= MIPI_DSI_MODE_LPM in the panel driver.

[ko1596]

dsi,flags = <(MIPI_DSI_MODE_VIDEO | MIPI_DSI_MODE_VIDEO_SYNC_PULSE | MIPI_DSI_MODE_LPM | MIPI_DSI_MODE_EOT_PACKET)>;

This is my setting in dts

I have set it to low power mode