Re: [EXT] [PATCH 2/2] drm/bridge: waveshare-dsi: Add support for 1..4 DSI data lanes

[Marek Vasut <marek.vasut@mailbox.org>]

On 1/13/26 7:41 AM, Joseph Guo wrote:
> On 1/13/2026 7:47 AM, Marek Vasut wrote:
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>> Parse the data lane count out of DT. Limit the supported data lanes
>> to 1..4 which is the maximum available DSI pairs on the connector of
>> any known panels which may use this bridge. Internally, this bridge
>> is an ChipOne ICN6211 which loads its register configuration from a
>> dedicated storage and its I2C does not seem to be accessible. The
>> ICN6211 also supports up to 4 DSI lanes, so this is a hard limit.
>>
>> To avoid any breakage on old DTs where the parsing of data lanes from
>> DT may fail, fall back to the original hard-coded value of 2 lanes and
>> warn user.
>>
>> The lane configuration is preconfigured in the bridge for each of the
>> WaveShare panels. The 13.3" DSI panel works with 4-lane configuration,
>> others seem to use 2-lane configuration. This is a hardware property,
>> so the actual count should come from DT.
>>
>>
> Hi Marek,
> 
> I don't have 4 lanes waveshare panel on my hands. Have you tested with the 4-lane panel already?
Yes, the 13.3" DSI panel is 4-lane 
https://www.waveshare.com/13.3inch-dsi-lcd.htm , I have it connected to 
Retronix Sparrow Hawk board which has 4-lane port.

See also this patch I submitted, that is the DT binding for it:

[PATCH 2/2] arm64: dts: renesas: sparrow-hawk: Add overlay for WaveShare 
Display 13.3"