0025-drm-tilcdc-fixup-mode-to-workaound-sync-for-tda998x.patch

From be17ff54f95af15fe293ed8a1c512a5dc652d7cc Mon Sep 17 00:00:00 2001
From: Cody Lacey <clacey@ti.com>
Date: Fri, 9 Aug 2013 14:07:01 -0500
Subject: [PATCH 25/27] drm/tilcdc fixup mode to workaound sync for tda998x

Add a fixup function that will flip the hsync priority and
add a hskew value that is used to shift the tda998x to the
right by a variable number of pixels depending on the mode.
This works around an issue with the sync timings that tilcdc
is outputing.
Created by: Darren Etheridge <detheridge@ti.com>
---
 drivers/gpu/drm/tilcdc/tilcdc_slave.c | 20 +++++++++++++++++++-
 1 file changed, 19 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/tilcdc/tilcdc_slave.c b/drivers/gpu/drm/tilcdc/tilcdc_slave.c
index 667540c..8d72c4d 100644
--- a/drivers/gpu/drm/tilcdc/tilcdc_slave.c
+++ b/drivers/gpu/drm/tilcdc/tilcdc_slave.c
@@ -65,13 +65,31 @@ static void slave_encoder_prepare(struct drm_encoder *encoder)
 	tilcdc_crtc_set_panel_info(encoder->crtc, slave_encoder->mod->info);
 }
 
+static bool slave_encoder_fixup(struct drm_encoder *encoder,
+		const struct drm_display_mode *mode,
+		struct drm_display_mode *adjusted_mode)
+{
+	adjusted_mode->hskew = mode->hsync_end - mode->hsync_start;
+	adjusted_mode->flags |= DRM_MODE_FLAG_HSKEW;
+
+	if (mode->flags & DRM_MODE_FLAG_NHSYNC) {
+		adjusted_mode->flags |= DRM_MODE_FLAG_PHSYNC;
+		adjusted_mode->flags &= ~DRM_MODE_FLAG_NHSYNC;
+	} else {
+		adjusted_mode->flags |= DRM_MODE_FLAG_NHSYNC;
+		adjusted_mode->flags &= ~DRM_MODE_FLAG_PHSYNC;
+	}
+
+	return drm_i2c_encoder_mode_fixup(encoder, mode, adjusted_mode);
+}
+
 static const struct drm_encoder_funcs slave_encoder_funcs = {
 		.destroy        = slave_encoder_destroy,
 };
 
 static const struct drm_encoder_helper_funcs slave_encoder_helper_funcs = {
 		.dpms           = drm_i2c_encoder_dpms,
-		.mode_fixup     = drm_i2c_encoder_mode_fixup,
+		.mode_fixup     = slave_encoder_fixup,
 		.prepare        = slave_encoder_prepare,
 		.commit         = drm_i2c_encoder_commit,
 		.mode_set       = drm_i2c_encoder_mode_set,
-- 
1.8.2.1