Hi,
On 23/02/2022 19:02, Kieran Bingham wrote:
Quoting Laurent Pinchart (2022-02-23 16:25:28)
Hello,
On Wed, Feb 23, 2022 at 04:17:22PM +0000, Kieran Bingham wrote:
Quoting Laurent Pinchart (2021-12-29 23:44:29)
On Sat, Dec 25, 2021 at 09:31:51AM +0300, Nikita Yushchenko wrote:
Hotplug events reported by bridge drivers over drm_bridge_hpd_notify()
get ignored unless somebody calls drm_bridge_hpd_enable(). When the
connector for the bridge is bridge_connector, such a call is done from
drm_bridge_connector_enable_hpd().
However drm_bridge_connector_enable_hpd() is never called on init paths,
documentation suggests that it is intended for suspend/resume paths.
Hmmmm... I'm in two minds about this. The problem description is
correct, but I wonder if HPD should be enabled unconditionally here, or
if this should be left to display drivers to control.
drivers/gpu/drm/imx/dcss/dcss-kms.c enables HPD manually at init time,
other drivers don't.
It feels like this should be under control of the display controller
driver, but I can't think of a use case for not enabling HPD at init
time. Any second opinion from anyone ?
This patch solves an issue I have where I have recently enabled HPD on
the SN65DSI86, but without this, I do not get calls to my .hpd_enable or
.hpd_disable hooks that I have added to the ti_sn_bridge_funcs.
So it needs to be enabled somewhere, and this seems reasonable to me?
It's not directly related to the display controller - as it's a factor
of the bridge?
On Falcon-V3U with HPD additions to SN65DSI86:
Tested-by: Kieran Bingham <kieran.bingham+renesas@xxxxxxxxxxxxxxxx>
If you think this is right, then
Reviewed-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>
I do, and at the very least it works for me, and fixes Nikita's issue so
to me that's enough for:
So who disables the HPD now?
Is the drm_bridge_connector_enable_hpd &
drm_bridge_connector_disable_hpd documentation now wrong as they talk
about suspend/resume handlers?
Tomi
