Re: Suggestion regarding x8 gang mode device tree changes

[Sowjanya Komatineni <skomatineni@nvidia.com>]

On 10/29/20 8:36 AM, Sowjanya Komatineni wrote:
>
> On 10/29/20 7:50 AM, Sakari Ailus wrote:
>> Hi Sowjanya,
>>
>> On Wed, Oct 28, 2020 at 06:48:59PM -0700, Sowjanya Komatineni wrote:
>>> Hi Sakari,
>>>
>>> Missed to add you to below patch series for HDMI2CSI bridge support
>>>
>>> https://patchwork.kernel.org/project/linux-media/cover/1603768763-25590-1-git-send-email-skomatineni@nvidia.com/ 
>>>
>>>
>>> Patch-10 of this series is for x8 capture from HDMI2CSI bridge.
>>>
>>> Would like to get your suggestion on x8 gang/combined ports capture
>>> implementation.
>> The majority of CSI-2 receiver devices support partitioning the lanes 
>> among
>> different PHYs in various ways. They do support usually up to four 
>> lanes,
>> but adding four more lanes is not a reason for making the API different.
>>
>> So instead, you should implement this as a single port that simply has 8
>> lanes.
>>
> Thanks Sakari for your reply.
>
> current v2 series treats as 8 lanes. You mean to not expose 2nd port 
> in device tree as VI/CSI side takes care of 2nd port as combined to 
> treat as 8 lane?

AS csi2 bus type supports max 4 data lanes with endpoint parse API.

Currently with x8 as single port, I am using bus-width with bus type as 
parallel in device tree and when using x4 using data-lanes with csi2 bus 
type and driver gets lanes based on either of this from DT.

Instead should we update endpoint parse API for max up to 8 lanes for 
data-lanes?

>
> Thanks
>
> Sowjanya
>