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* [PATCH v2] drm/bridge: anx7625: Tune K value for IVO panel
@ 2021-08-06 10:09 Xin Ji
  0 siblings, 0 replies; 3+ messages in thread
From: Xin Ji @ 2021-08-06 10:09 UTC (permalink / raw)
  To: Robert Foss, Nicolas Boichat, Andrzej Hajda
  Cc: Neil Armstrong, Laurent Pinchart, Jonas Karlman, Dan Carpenter,
	David Airlie, Daniel Vetter, Boris Brezillon, Sam Ravnborg,
	Hsin-Yi Wang, Torsten Duwe, Vasily Khoruzhick, Marek Szyprowski,
	Bernie Liang, Qilin Wen, dri-devel, linux-kernel, devel

IVO panel require less input video clock variation than video clock
variation in DP CTS spec.

This patch decreases the K value of ANX7625 which will shrink eDP Tx
video clock variation to meet IVO panel's requirement.

Acked-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Xin Ji <xji@analogixsemi.com>
---
 drivers/gpu/drm/bridge/analogix/anx7625.c | 24 ++++++++++++++++++++---
 drivers/gpu/drm/bridge/analogix/anx7625.h |  4 +++-
 2 files changed, 24 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/bridge/analogix/anx7625.c b/drivers/gpu/drm/bridge/analogix/anx7625.c
index a3d82377066b..9b9e3984dd38 100644
--- a/drivers/gpu/drm/bridge/analogix/anx7625.c
+++ b/drivers/gpu/drm/bridge/analogix/anx7625.c
@@ -384,6 +384,25 @@ static int anx7625_odfc_config(struct anx7625_data *ctx,
 	return ret;
 }
 
+/*
+ * The MIPI source video data exist large variation (e.g. 59Hz ~ 61Hz),
+ * anx7625 defined K ratio for matching MIPI input video clock and
+ * DP output video clock. Increase K value can match bigger video data
+ * variation. IVO panel has small variation than DP CTS spec, need
+ * decrease the K value.
+ */
+static int anx7625_set_k_value(struct anx7625_data *ctx)
+{
+	struct edid *edid = (struct edid *)ctx->slimport_edid_p.edid_raw_data;
+
+	if (edid->mfg_id[0] == IVO_MID0 && edid->mfg_id[1] == IVO_MID1)
+		return anx7625_reg_write(ctx, ctx->i2c.rx_p1_client,
+					 MIPI_DIGITAL_ADJ_1, 0x3B);
+
+	return anx7625_reg_write(ctx, ctx->i2c.rx_p1_client,
+				 MIPI_DIGITAL_ADJ_1, 0x3D);
+}
+
 static int anx7625_dsi_video_timing_config(struct anx7625_data *ctx)
 {
 	struct device *dev = &ctx->client->dev;
@@ -470,9 +489,8 @@ static int anx7625_dsi_video_timing_config(struct anx7625_data *ctx)
 			MIPI_PLL_N_NUM_15_8, (n >> 8) & 0xff);
 	ret |= anx7625_reg_write(ctx, ctx->i2c.rx_p1_client, MIPI_PLL_N_NUM_7_0,
 			(n & 0xff));
-	/* Diff */
-	ret |= anx7625_reg_write(ctx, ctx->i2c.rx_p1_client,
-			MIPI_DIGITAL_ADJ_1, 0x3D);
+
+	anx7625_set_k_value(ctx);
 
 	ret |= anx7625_odfc_config(ctx, post_divider - 1);
 
diff --git a/drivers/gpu/drm/bridge/analogix/anx7625.h b/drivers/gpu/drm/bridge/analogix/anx7625.h
index 034c3840028f..6dcf64c703f9 100644
--- a/drivers/gpu/drm/bridge/analogix/anx7625.h
+++ b/drivers/gpu/drm/bridge/analogix/anx7625.h
@@ -210,7 +210,9 @@
 #define  MIPI_VIDEO_STABLE_CNT           0x0A
 
 #define  MIPI_LANE_CTRL_10               0x0F
-#define  MIPI_DIGITAL_ADJ_1   0x1B
+#define  MIPI_DIGITAL_ADJ_1     0x1B
+#define  IVO_MID0               0x26
+#define  IVO_MID1               0xCF
 
 #define  MIPI_PLL_M_NUM_23_16   0x1E
 #define  MIPI_PLL_M_NUM_15_8    0x1F
-- 
2.25.1


^ permalink raw reply related	[flat|nested] 3+ messages in thread
* Re: [PATCH v2] drm/bridge: anx7625: Tune K value for IVO panel
  2021-08-06 10:44 Xin Ji
@ 2021-08-06 11:00 ` Robert Foss
  0 siblings, 0 replies; 3+ messages in thread
From: Robert Foss @ 2021-08-06 11:00 UTC (permalink / raw)
  To: Xin Ji
  Cc: Nicolas Boichat, Andrzej Hajda, Neil Armstrong, Laurent Pinchart,
	Jonas Karlman, Dan Carpenter, David Airlie, Daniel Vetter,
	Boris Brezillon, Sam Ravnborg, Hsin-Yi Wang, Torsten Duwe,
	Vasily Khoruzhick, Marek Szyprowski, Bernie Liang, Qilin Wen,
	dri-devel, linux-kernel, devel

Applied to drm-misc-next

^ permalink raw reply	[flat|nested] 3+ messages in thread
* [PATCH v2] drm/bridge: anx7625: Tune K value for IVO panel
@ 2021-08-06 10:44 Xin Ji
  2021-08-06 11:00 ` Robert Foss
  0 siblings, 1 reply; 3+ messages in thread
From: Xin Ji @ 2021-08-06 10:44 UTC (permalink / raw)
  To: robert.foss, drinkcat, a.hajda
  Cc: narmstrong, Laurent.pinchart, jonas, dan.carpenter, airlied,
	daniel, boris.brezillon, sam, hsinyi, duwe, anarsoul,
	m.szyprowski, bliang, qwen, dri-devel, linux-kernel, devel,
	Xin Ji

IVO panel require less input video clock variation than video clock
variation in DP CTS spec.

This patch decreases the K value of ANX7625 which will shrink eDP Tx
video clock variation to meet IVO panel's requirement.

Acked-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Xin Ji <xji@analogixsemi.com>
---
 drivers/gpu/drm/bridge/analogix/anx7625.c | 24 ++++++++++++++++++++---
 drivers/gpu/drm/bridge/analogix/anx7625.h |  4 +++-
 2 files changed, 24 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/bridge/analogix/anx7625.c b/drivers/gpu/drm/bridge/analogix/anx7625.c
index a3d82377066b..9b9e3984dd38 100644
--- a/drivers/gpu/drm/bridge/analogix/anx7625.c
+++ b/drivers/gpu/drm/bridge/analogix/anx7625.c
@@ -384,6 +384,25 @@ static int anx7625_odfc_config(struct anx7625_data *ctx,
 	return ret;
 }
 
+/*
+ * The MIPI source video data exist large variation (e.g. 59Hz ~ 61Hz),
+ * anx7625 defined K ratio for matching MIPI input video clock and
+ * DP output video clock. Increase K value can match bigger video data
+ * variation. IVO panel has small variation than DP CTS spec, need
+ * decrease the K value.
+ */
+static int anx7625_set_k_value(struct anx7625_data *ctx)
+{
+	struct edid *edid = (struct edid *)ctx->slimport_edid_p.edid_raw_data;
+
+	if (edid->mfg_id[0] == IVO_MID0 && edid->mfg_id[1] == IVO_MID1)
+		return anx7625_reg_write(ctx, ctx->i2c.rx_p1_client,
+					 MIPI_DIGITAL_ADJ_1, 0x3B);
+
+	return anx7625_reg_write(ctx, ctx->i2c.rx_p1_client,
+				 MIPI_DIGITAL_ADJ_1, 0x3D);
+}
+
 static int anx7625_dsi_video_timing_config(struct anx7625_data *ctx)
 {
 	struct device *dev = &ctx->client->dev;
@@ -470,9 +489,8 @@ static int anx7625_dsi_video_timing_config(struct anx7625_data *ctx)
 			MIPI_PLL_N_NUM_15_8, (n >> 8) & 0xff);
 	ret |= anx7625_reg_write(ctx, ctx->i2c.rx_p1_client, MIPI_PLL_N_NUM_7_0,
 			(n & 0xff));
-	/* Diff */
-	ret |= anx7625_reg_write(ctx, ctx->i2c.rx_p1_client,
-			MIPI_DIGITAL_ADJ_1, 0x3D);
+
+	anx7625_set_k_value(ctx);
 
 	ret |= anx7625_odfc_config(ctx, post_divider - 1);
 
diff --git a/drivers/gpu/drm/bridge/analogix/anx7625.h b/drivers/gpu/drm/bridge/analogix/anx7625.h
index 034c3840028f..6dcf64c703f9 100644
--- a/drivers/gpu/drm/bridge/analogix/anx7625.h
+++ b/drivers/gpu/drm/bridge/analogix/anx7625.h
@@ -210,7 +210,9 @@
 #define  MIPI_VIDEO_STABLE_CNT           0x0A
 
 #define  MIPI_LANE_CTRL_10               0x0F
-#define  MIPI_DIGITAL_ADJ_1   0x1B
+#define  MIPI_DIGITAL_ADJ_1     0x1B
+#define  IVO_MID0               0x26
+#define  IVO_MID1               0xCF
 
 #define  MIPI_PLL_M_NUM_23_16   0x1E
 #define  MIPI_PLL_M_NUM_15_8    0x1F
-- 
2.25.1


^ permalink raw reply related	[flat|nested] 3+ messages in thread
end of thread, other threads:[~2021-08-06 11:00 UTC | newest]

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2021-08-06 10:09 [PATCH v2] drm/bridge: anx7625: Tune K value for IVO panel Xin Ji
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2021-08-06 11:00 ` Robert Foss

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