Hi all
I am developing with a iMX8QXP Varisicite SOM based board a MIPI-DSI display interface. The display is based on a ILI9488 controller with only 1 lane, it is 480x320.
I have patched the file drivers/gpu/drm/bridge/nwl-dsi.c
The function nwl_dsi_bridge_atomic_check makes lanes=1 not a choice with this code
if (config->lanes < 2 || config->lanes > 4)
return -EINVAL;
With "(config->lanes < 1" the function continues executing.
From then on the driver loads, but I see this message in the kernel
[ 8.649716] nwl-dsi 56228000.dsi_host: [drm:nwl_dsi_host_transfer [nwl_dsi]] *ERROR* [11] DSI transfer timed out
It is displayed after trying to take the panel out of sleep
ret = mipi_dsi_dcs_exit_sleep_mode(dsi);
if (ret < 0) {
dev_err(ctx->dev, "Failed to exit sleep mode: %d\n", ret);
Loading a dummy panel, with no initializacion with mipi-dsi commands, all the functions in the drm panel are called (drm_panel_funcs prepare, enable and get_modes),
but with the oscilloscope I cannot see any clear signal in the CLK lane (CH3 & CH4), and the DATA lane (CH1 & CH2) is not differential
This is the MIPI-DSI part of the device tree
&mipi0_dphy {
status = "okay";
};
&mipi0_dsi_host {
status = "okay";
fsl,clock-drop-level = <2>;
panel@0 {
#address-cells = <1>;
#size-cells = <0>;
reg = <0>;
power-supply = <®_mipi0disp>;
backlight = <&backlight>;
reset-gpios = <&gpio_hmi1 15 GPIO_ACTIVE_HIGH>;
compatible = "my_panel,my_ili9488";
panel-width-mm = <42>;
panel-height-mm = <82>;
port {
panel0_in: endpoint {
remote-endpoint = <&mipi0_panel_out>;
};
};
};
ports {
port@1 {
#address-cells = <1>;
#size-cells = <0>;
reg = <1>;
mipi0_panel_out: endpoint {
remote-endpoint = <&panel0_in>;
};
};
};
};
Any suggestion?
Thanks in advance,
M
PS Without the dummy panel in the initialization process I cannot see the Low Power mode commands neither.
