From 205b6dd5b7990d06d681ebda890a7c119236e8f4 Mon Sep 17 00:00:00 2001
From: Pratyush Yadav
Date: Fri, 23 Feb 2024 13:53:01 +0530
Subject: [PATCH] media: cadence: csi2rx: configure DPHY before starting source
stream
[ Upstream commit fd64dda48f7e3f67ada1e1fe47e784ab350da72e ]
When the source device is operating above 1.5 Gbps per lane, it needs to
send the Skew Calibration Sequence before sending any HS data. If the
DPHY is initialized after the source stream is started, then it might
miss the sequence and not be able to receive data properly. Move the
start of source subdev to the end of the sequence to make sure
everything is ready to receive data before the source starts streaming.
Signed-off-by: Pratyush Yadav
Fixes: 3295cf1241d3 ("media: cadence: Add support for external dphy")
Tested-by: Julien Massot
Tested-by: Changhuang Liang
Reviewed-by: Julien Massot
Reviewed-by: Changhuang Liang
Signed-off-by: Jai Luthra
Signed-off-by: Sakari Ailus
Signed-off-by: Hans Verkuil
Signed-off-by: Sasha Levin
---
drivers/media/platform/cadence/cdns-csi2rx.c | 26 +++++++++++---------
1 file changed, 14 insertions(+), 12 deletions(-)
diff --git a/drivers/media/platform/cadence/cdns-csi2rx.c b/drivers/media/platform/cadence/cdns-csi2rx.c
index f2ce458ebb1d..2d803cf31e9d 100644
--- a/drivers/media/platform/cadence/cdns-csi2rx.c
+++ b/drivers/media/platform/cadence/cdns-csi2rx.c
@@ -164,10 +164,6 @@ static int csi2rx_start(struct csi2rx_priv *csi2rx)
writel(reg, csi2rx->base + CSI2RX_STATIC_CFG_REG);
- ret = v4l2_subdev_call(csi2rx->source_subdev, video, s_stream, true);
- if (ret)
- goto err_disable_pclk;
-
/* Enable DPHY clk and data lanes. */
if (csi2rx->dphy) {
reg = CSI2RX_DPHY_CL_EN | CSI2RX_DPHY_CL_RST;
@@ -177,6 +173,13 @@ static int csi2rx_start(struct csi2rx_priv *csi2rx)
}
writel(reg, csi2rx->base + CSI2RX_DPHY_LANE_CTRL_REG);
+
+ ret = csi2rx_configure_ext_dphy(csi2rx);
+ if (ret) {
+ dev_err(csi2rx->dev,
+ "Failed to configure external DPHY: %d\n", ret);
+ goto err_disable_pclk;
+ }
}
/*
@@ -213,14 +216,9 @@ static int csi2rx_start(struct csi2rx_priv *csi2rx)
reset_control_deassert(csi2rx->sys_rst);
- if (csi2rx->dphy) {
- ret = csi2rx_configure_ext_dphy(csi2rx);
- if (ret) {
- dev_err(csi2rx->dev,
- "Failed to configure external DPHY: %d\n", ret);
- goto err_disable_sysclk;
- }
- }
+ ret = v4l2_subdev_call(csi2rx->source_subdev, video, s_stream, true);
+ if (ret)
+ goto err_disable_sysclk;
clk_disable_unprepare(csi2rx->p_clk);
@@ -234,6 +232,10 @@ err_disable_pixclk:
clk_disable_unprepare(csi2rx->pixel_clk[i - 1]);
}
+ if (csi2rx->dphy) {
+ writel(0, csi2rx->base + CSI2RX_DPHY_LANE_CTRL_REG);
+ phy_power_off(csi2rx->dphy);
+ }
err_disable_pclk:
clk_disable_unprepare(csi2rx->p_clk);