On Wed, Mar 30, 2016 at 01:32:04PM -0700, Guenter Roeck wrote:

Hi,

On Mon, Feb 15, 2016 at 07:09:36PM +0800, Yakir Yang wrote:

quoted

Split the dp core driver from exynos directory to bridge directory,
and rename the core driver to analogix_dp_*, rename the platform
code to exynos_dp.

Beside the new analogix_dp driver would export six hooks.
"analogix_dp_bind()" and "analogix_dp_unbind()"
"analogix_dp_suspned()" and "analogix_dp_resume()"
"analogix_dp_detect()" and "analogix_dp_get_modes()"

The bind/unbind symbols is used for analogix platform driver to connect
with analogix_dp core driver. And the detect/get_modes is used for analogix
platform driver to init the connector.

They reason why connector need register in helper driver is rockchip drm
haven't implement the atomic API, but Exynos drm have implement it, so
there would need two different connector helper functions, that's why we
leave the connector register in helper driver.

Signed-off-by: Yakir Yang <redacted>

[ ... ]

quoted

diff --git a/drivers/gpu/drm/bridge/analogix/Makefile b/drivers/gpu/drm/bridge/analogix/Makefile
new file mode 100644
index 0000000..9107b86
--- /dev/null
+++ b/drivers/gpu/drm/bridge/analogix/Makefile

@@ -0,0 +1 @@
+obj-$(CONFIG_DRM_ANALOGIX_DP) += analogix_dp_core.o analogix_dp_reg.o

This results in the following build errors if DRM_ANALOGIX_DP
is configured as module.

ERROR: "analogix_dp_start_video" [drivers/gpu/drm/bridge/analogix/analogix_dp_core.ko] undefined!
ERROR: "analogix_dp_get_lane0_link_training" [drivers/gpu/drm/bridge/analogix/analogix_dp_core.ko] undefined!
ERROR: "analogix_dp_get_lane1_link_training" [drivers/gpu/drm/bridge/analogix/analogix_dp_core.ko] undefined!
ERROR: "analogix_dp_get_lane2_link_training" [drivers/gpu/drm/bridge/analogix/analogix_dp_core.ko] undefined!
ERROR: "analogix_dp_get_lane3_link_training" [drivers/gpu/drm/bridge/analogix/analogix_dp_core.ko] undefined!
ERROR: "analogix_dp_get_lane_count" [drivers/gpu/drm/bridge/analogix/analogix_dp_core.ko] undefined!
ERROR: "analogix_dp_get_link_bandwidth" [drivers/gpu/drm/bridge/analogix/analogix_dp_core.ko] undefined!

[ and so on ]

Ugh... most of these functions shouldn't be there in the first place. We
have helpers in the core that already do this. Most of the functionality
is duplicated in this driver.

I realize that this is a problem that existed in the Exynos DP driver,
but somebody really ought to rewrite those parts to make use of the DRM
DP helpers.

Thierry
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