Hi Kenneth,

> -----Original Message-----
> From: Kenneth Sloat <[email protected]>
> Sent: Thursday, August 20, 2020 2:18 PM
> To: Hyun Kwon <[email protected]>; [email protected]
> Cc: Michal Simek <[email protected]>; [email protected]; linux-
> [email protected]; [email protected];
> [email protected]; [email protected];
> [email protected]
> Subject: dt-bindings: display: xlnx: mixer: Inconsistent pixel format 
> terminology
> in dt docs
> 
> Hello,
> 
> The Xilinx Video mixer IP uses the DRM fourcc string as a device tree binding 
> in
> order to describe the format for a specific DRM layer/plane. Currently, in the
> device tree doc in
> "Documentation/devicetree/bindings/dma/xilinx/xilinx_frmbuf.txt" there is a 
> list
> called "VIDEO FORMATS" with a table containing "Mixer IP Format" and
> associated "Driver supported Format String" (fourcc). In general, this table 
> is not
> helpful, because "Mixer IP Format" does not match the Xilinx IP datasheet
> terminology for formats but rather some other commonly used nomenclature.
> This is also inconsistent from other Xilinx dts binding docs which specify the
> actual correct IP name and at times list other format nomenclature where
> helpful (i.e. xilinx_frmbuf.txt)
> 
> My suggestion is to remove the current "Mixer IP Format" strings in the doc 
> and
> replace them with the actual IP names in the datasheet (which also match those
> used in Xilinx's Vivado FPGA tool). Otherwise, the programmer must cross
> reference other dts documentation or the code in order to figure these out. I 
> am
> happy to provide a patch for this but wanted to throw out the suggestion 
> first.

I agree. The bindings should be in sync with datasheet and not rely on
software definitions. Since the driver is only in Xilinx vendor tree,
please send directly to [email protected].

Thanks!

-hyun

> 
> Thanks
> 
> Sincerely,
> Ken Sloat

Reply via email to