From a8947838596a7c8cbcd6cd955c1bc3da56a15152 Mon Sep 17 00:00:00 2001
From: Xin Ji <xji@analogixsemi.com>
Date: Fri, 6 Aug 2021 18:44:07 +0800
Subject: drm/bridge: anx7625: Tune K value for IVO panel
Git-commit: 7d066dc73929d5b14501a47ae9cad4f49fe22abc
Patch-mainline: v5.15-rc1
References: jsc#PED-1166 jsc#PED-1168 jsc#PED-1170 jsc#PED-1218 jsc#PED-1220 jsc#PED-1222 jsc#PED-1223 jsc#PED-1225
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>
Signed-off-by: Robert Foss <robert.foss@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20210806104407.2208538-1-xji@analogixsemi.com
Acked-by: Patrik Jakobsson <pjakobsson@suse.de>
---
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 920824d8df2f..14d73fb1dd15 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
--
2.38.1