RE: [PATCH v1 2/2] drm/virtio: Add the hotplug_mode_update property for rescanning of modes

["Kasireddy, Vivek" <vivek.kasireddy@xxxxxxxxx>]

Hi Gerd,

> 
> On Thu, Nov 17, 2022 at 05:30:54PM -0800, Vivek Kasireddy wrote:
> > Setting this property will allow the userspace to look for new modes or
> > position info when a hotplug event occurs.
> 
> This works just fine for modes today.
> 
> I assume this is this need to have userspace also check for position
> info updates added by patch #1)?
[Kasireddy, Vivek] Yes, that is exactly the reason why this property is needed. In 
other words, Mutter does not seem to look at suggested_x/y values (or position info)
if hotplug_mode_property is not there. Here is the relevant piece of code in Mutter:

static gboolean
meta_monitor_normal_get_suggested_position (MetaMonitor *monitor,
                                            int         *x,
                                            int         *y)
{
  const MetaOutputInfo *output_info =
    meta_monitor_get_main_output_info (monitor);

  if (!output_info->hotplug_mode_update)
    return FALSE;

  if (output_info->suggested_x < 0 && output_info->suggested_y < 0)
    return FALSE;

  if (x)
    *x = output_info->suggested_x;

  if (y)
    *y = output_info->suggested_y;


Thanks,
Vivek

> 
> take care,
>   Gerd