Re: [PATCH v7] media: i2c: add lt6911uxe hdmi bridge driver

["Yan, Dongcheng" <dongcheng.yan@intel.com>]

Hi Sakari,

On 3/7/2025 6:55 PM, Sakari Ailus wrote:
> Hi Dongcheng,
> 
> On Fri, Mar 07, 2025 at 06:00:56PM +0800, Yan, Dongcheng wrote:
>>>> +		/* MIPI Clock Rate = ByteClock × 4, defined in lt6911uxe spec */
>>>
>>> What does the byte clock actually signify? Bytes per second on CSI-2?
>>>
>>
>> This is more like a DSI related calculation, I think lontium uses the
>> expression related to HDMI and DSI in the video field.
>> dsi_clk = Bitclk / 2 = Byteclk * 4, dsi_clk is mipi clk, which is used
>> as link_freq.
>> Here Bitclk = HTS * VTS * fps * bpp / lanes.
> 
> The PHY for CSI-2 and DSI is the same, so the same formula is applicable.
> The chip is HDMI/CSI-2 (isn'it it?), so I wonder how DSI is related to
> this. How many HDMI lanes are in use?
> 

My expression misunderstood you. I am just explaining why ByteClock is
used here to name. Yes, ByteClock is Bytes per second on CSI-2, and
because CSI-2 uses DDR(Double Data Rate), here link_freq = bitclk / 2 =
ByteClock * 4.

Thanks,
Dongcheng