video: exynos_dp: adjust voltage swing and pre-emphasis during Link Training

This patch adds adjustement for voltage swing and pre-emphasis during
Link Training procedure. According to the DP specification, unless all
the LANEx_CR_DONE bits are set, the transmitter must read
the ADJUST_REQUEST_LANEx_x, increase the voltage swing according to
the request, and update the TRAINING_LANEx_SET bytes to match the new
voltage swing setting.

Refer to the DP specification v1.1a, Section 3.5.1.3 Link Training.
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Florian Tobias Schandinat <FlorianSchandinat@gmx.de>

drivers/video/exynos/exynos_dp_core.h

@@ -144,7 +144,7 @@ void exynos_dp_disable_scrambling(struct exynos_dp_device *dp);
 #define DPCD_ADDR_TRAINING_PATTERN_SET		0x0102
 #define DPCD_ADDR_TRAINING_LANE0_SET		0x0103
 #define DPCD_ADDR_LANE0_1_STATUS		0x0202
-#define DPCD_ADDR_LANE_ALIGN__STATUS_UPDATED	0x0204
+#define DPCD_ADDR_LANE_ALIGN_STATUS_UPDATED	0x0204
 #define DPCD_ADDR_ADJUST_REQUEST_LANE0_1	0x0206
 #define DPCD_ADDR_ADJUST_REQUEST_LANE2_3	0x0207
 #define DPCD_ADDR_TEST_REQUEST			0x0218