Re: [PATCH 2/2] arm: dts: mediatek: mt6589: add basic support for Lenovo B8000-F

[Akari Tsuyukusa]

Hi Angelo, thanks for the feedback.

On Thu, Mar 5, 2026 at 6:46 PM AngeloGioacchino Del Regno
<angelogioacchino.delregno@xxxxxxxxxxxxx> wrote:
> Okay, but this is just a simple framebuffer and a UART; while it may be in some
> way useful, there's already one device based on MT6589 that was upstreamed with
> just a framebuffer and a serial port, but then didn't receive any more support.
>
> Could you please extend your efforts a little and push at least some support for
> clock controllers and power domains for the MT6589 SoC to make it at least barely
> useful?

Your point is valid. I saw similar minimal Device Trees in
"arch/arm/boot/dts/mediatek/" . Currently, I am actively working on
MT6589 kernel mainlining and Lenovo YOGA Tablet support, so I submitted
this patch as initial support for this device.

I will send patches to add the following features in the near future
(preferably within this month):

- Clock
I wrote drivers and they seem to be working.
However, some parent clocks are unknown.

- Pinctrl
I refactored it to common-v2, paris and it's working.
A little more work is needed to add support for R0, TDSEL, RDSEL, and
device tree binding.

- PWRAP and MT6320 PMIC RTC
PWRAP is working fine. This seems to be almost the same as MT8135.
MT6320 PMIC has confirmed RTC operation, but it will take a little more
time as I haven't written the regulator driver yet.

Additional time is required to add the following features:

- Power Domains (scpsys)
I've written a driver, but I haven't checked that it works yet.
And, some features are missing for full support.

- eMMC/SD (MSDC)
Likely compatible with "mtk-sd.c". I have written in Device Tree, but
it is not working on the device. It needs debug mode.

- USB
Almost certainly compatible with "mediatek,mtk-musb" and
"mediatek,generic-tphy-v1". The device is not recognized by the PC,
and there are logs saying "couldn't find an available UDC".
It may take more time.

- UART DMA
Boots without any errors, but I can't confirm its operation because
I haven't soldered UART.

- I2C
I don't know the details, but the clock is supplied from the PMIC,
but PMIC clock driver does not exist. Fortunately, MediaTek engineers
implemented MT6589 compatibility in the I2C driver (but it is not added
in the MT6589 Device Tree).

- I2C devices (only in mainline)
Touchscreen: syna,rmi4-i2c
Accelerometer: bosch,bma255
Magnetometer: bosch,bmm150
Fuel Gauge: ti,bq27541
Battery Charger: ti,bq24196

- SPI
Like I2C, there is a driver (it seems that the PMIC clock is not
required for SPI), but  I don't know what devices are connected.

I am committed to making MT6589 and the Lenovo YOGA Tablet fully
functional in the mainline kernel. I will send these additional patches
as soon as they are ready for review.

Best regards,
Akari