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"Failed to attach bridge" when trying to use MIPI DSI output

Question asked by Amaan Cheval on Jan 20, 2020
Latest reply on Jan 20, 2020 by igorpadykov



I have the VAR-DART-MX8M Mini (originally had an "LD" configuration to convert MIPI DSI to LVDS using the SN65DSI84, but the hardware configuration was changed using instructions as in the file attached).

I'm running Android 9.0 on the board, following these instructions, so the board is running Linux 4.14.78.


I am attempting to backport drivers for a new panel (my panel uses the ILI9881C IC and I'm using the rm67191 device tree and driver code as a reference, backporting from the most recent kernel), however I get an error before my panel driver is even initiated.


In the default configuration (i.e. not having added the new panel's driver or custom device tree files), I see this error in the logs (through `dmesg`):

[    1.369380] sn65dsi83 0-002c: failed reading at 0x09
[    1.374373] sn65dsi83 0-002c: Failed to reset the device
[    1.379699] sn65dsi83 0-002c: Failed to reset the device
[    1.388714] [drm] Supports vblank timestamp caching Rev 2 (21
[    1.395353] [drm] No driver support for vblank timestamp quer
[    1.401364] imx-drm display-subsystem: bound imx-lcdif-crtc.0
 (ops lcdif_crtc_ops)
[    1.409038] imx_sec_dsim_drv 32e10000.mipi_dsi: version numbe
r is 0x1060200
[    1.416060] imx_sec_dsim_drv 32e10000.mipi_dsi: Failed to att
ach bridge: 32e10000.mipi_dsi
[    1.424340] imx_sec_dsim_drv 32e10000.mipi_dsi: failed to bin
d sec dsim bridge: -19


Understandably, the sn65dsi83 errors are because the IC isn't on the board anymore, and I can make them go away by disabling it in the device tree.

However, can someone shed some light on what the "Failed to attach bridge" error is about? Even with my customized DTS and driver files (patch attached), I still see the same error.


In addition, could someone clarify whether I'm on the right track with this patch? I've seen some posts on NXP using the DCSS system instead of the default LCDIF one.