Re: [PATCH v9 20/23] drm/rockchip: Make VOP driver optional

On Wed, Mar 30, 2022 at 08:50:09PM +0800, Andy Yan wrote:

Hi Sascha:

On 3/30/22 14:39, Sascha Hauer wrote:

quoted

Hi Andy,

On Tue, Mar 29, 2022 at 07:56:27PM +0800, Andy Yan wrote:

quoted

Hi Sascha:

On 3/28/22 23:11, Sascha Hauer wrote:

quoted

With upcoming VOP2 support VOP won't be the only choice anymore, so make
the VOP driver optional.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
---
   drivers/gpu/drm/rockchip/Kconfig            | 8 ++++++++
   drivers/gpu/drm/rockchip/Makefile           | 3 ++-
   drivers/gpu/drm/rockchip/rockchip_drm_drv.c | 2 +-
   3 files changed, 11 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/rockchip/Kconfig b/drivers/gpu/drm/rockchip/Kconfig
index fa5cfda4e90e3..7d22e2997a571 100644
--- a/drivers/gpu/drm/rockchip/Kconfig
+++ b/drivers/gpu/drm/rockchip/Kconfig

@@ -23,8 +23,16 @@ config DRM_ROCKCHIP
   if DRM_ROCKCHIP
+config ROCKCHIP_VOP
+	bool "Rockchip VOP driver"
+	default y
+	help
+	  This selects support for the VOP driver. You should enable it
+	  on all older SoCs up to RK3399.

That reminds me that I wanted to rephrase this. Will change in next
round.

quoted

quoted

+
   config ROCKCHIP_ANALOGIX_DP
   	bool "Rockchip specific extensions for Analogix DP driver"
+	depends on ROCKCHIP_VOP

Aanlogix dp is also on vop2 base soc such as  rk356x and rk3588.

BTW I just looked at the downstream driver. Here we have the same
situation that the analogix dp driver calls rockchip_drm_wait_vact_end()
which is implemented in the VOP driver, so when the analogix dp driver
is actually used on a VOP2 SoC then it is either used in a way that
rockchip_drm_wait_vact_end() will never be called or it explodes in all
colours.

quoted

I added the dependency because analogix_dp-rockchip.c calls
rockchip_drm_wait_vact_end() which is implemented in the VOP driver,
so this driver currenty can't work with the VOP2 driver and can't
be linked without the VOP driver being present.
I'll add a few words to the commit message.

Maybe a better direction is move rockchip_drm_wait_vact_end from the VOP
driver to rockchip_drm_drv.c

I am not sure if that's really worth it. Yes, the direction might be the
right one, but I would really prefer when somebody does the change who
can test and confirm that the analogix dp really works with VOP2 in the
end.

Sascha

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