lkml.org 
[lkml]   [2023]   [Feb]   [14]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
Date
SubjectRe: [PATCH v1 RFC] video/hdmi: Fix HDMI_VENDOR_INFOFRAME_SIZE
On Mon, Feb 13, 2023 at 12:11 PM Ville Syrjälä
<ville.syrjala@linux.intel.com> wrote:
[...]
> > One could use HDMI_VENDOR_INFOFRAME_SIZE with this as well:
> > u8 buffer[HDMI_INFOFRAME_SIZE(VENDOR)];
> > But it would only result in an 8 byte wide buffer.
> > Nobody uses it like this yet.
>
> Not sure that would make any sense since a vendor
> specific infoframe has no defined size until you
> figure out which vendor defined it (via the OUI).
My understanding is that all of the existing HDMI vendor infoframe
code is built for HDMI_IEEE_OUI.

> I suppose the current value of 4 is also a bit nonsense
> as well then, becasue that is a legal value for the
> HDMI 1.4 vendor specific infoframe, but might not be
> valid for any other infoframe.
>
> We should perhaps just get rid of HDMI_VENDOR_INFOFRAME_SIZE
> entirely.
My thought was to make it the correct size for
drm_hdmi_vendor_infoframe_from_display_mode(). Then developers using
this "common" vendor infoframe don't have to worry much.
If there's another vendor infoframe implementation (which I'm not
aware of, but it may exist - since as you point out: it's vendor
specific) then the driver code shouldn't use
drm_hdmi_vendor_infoframe_from_display_mode() but rather implement
something custom. At that point the person implementing that will also
need to know their specific infoframe maximum size.


Best regards,
Martin

\
 
 \ /
  Last update: 2023-03-27 00:23    [W:0.053 / U:0.188 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site