[PATCH v2 16/17] drm: Nuke mode->private_flags

[abhinavk at codeaurora.org]

Hi Ville

Thanks for the patch.

Our understanding of private_flags was that we can use it within our 
drivers to handle vendor specific features.
Hence we do have several features in our downstream drivers as well as 
some planned work based on this.

This was the only method to pass around and consume the driver only 
information which we have been using.

In the current qualcomm upstream display drivers, the only usage of the 
mode->private_flags is what you have removed in 
https://patchwork.kernel.org/patch/11473497/.

However, for other projects which do not use upstream drivers yet, we 
have several features already which are using the mode->private_flags.

We do have a plan to remove the usage of mode->private_flags for those 
drivers as well but its not ready yet.

These downstream drivers still use the upstream drm files for 
compilation.

So how it works is we use all the headers under include/drm and also the 
files under drivers/gpu/drm as-it-is from upstream but maintain our 
drivers on top of this.

Removing this will result in compilation failures for us in the near 
term.

Can we keep this one as-it-is and when our changes are ready to post it 
upstream we shall remove private_flags from the drm_modes.h

Thanks

Abhinav

On 2020-04-03 13:40, Ville Syrjala wrote:
> From: Ville Syrjälä <ville.syrjala at linux.intel.com>
> 
> The last two uses of mode->private_flags (in i915 and gma500)
> are now gone. So let's remove mode->private_flags entirely.
> 
> CC: Sam Ravnborg <sam at ravnborg.org>
> Cc: Daniel Vetter <daniel.vetter at ffwll.ch>
> Cc: Emil Velikov <emil.l.velikov at gmail.com>
> Signed-off-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
> ---
>  include/drm/drm_modes.h | 10 ----------
>  1 file changed, 10 deletions(-)
> 
> diff --git a/include/drm/drm_modes.h b/include/drm/drm_modes.h
> index 47d62b9d8d20..1e97138a9b8c 100644
> --- a/include/drm/drm_modes.h
> +++ b/include/drm/drm_modes.h
> @@ -348,16 +348,6 @@ struct drm_display_mode {
>  	 */
>  	u8 type;
> 
> -	/**
> -	 * @private_flags:
> -	 *
> -	 * Driver private flags. private_flags can only be used for mode
> -	 * objects passed to drivers in modeset operations. It shouldn't be 
> used
> -	 * by atomic drivers since they can store any additional data by
> -	 * subclassing state structures.
> -	 */
> -	u8 private_flags;
> -
>  	/**
>  	 * @head:
>  	 *