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From:   Jack Zhu <jack.zhu@starfivetech.com>
To:     Mauro Carvalho Chehab <mchehab@kernel.org>,
        Maxime Ripard <mripard@kernel.org>,
        Rob Herring <robh+dt@kernel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
        Robert Foss <rfoss@kernel.org>,
        "Todor Tomov" <todor.too@gmail.com>,
        Philipp Zabel <p.zabel@pengutronix.de>,
        "Laurent Pinchart" <laurent.pinchart@ideasonboard.com>,
        Ezequiel Garcia <ezequiel@vanguardiasur.com.ar>,
        Hans Verkuil <hverkuil-cisco@xs4all.nl>,
        Eugen Hristev <eugen.hristev@collabora.com>
CC:     <linux-media@vger.kernel.org>, <devicetree@vger.kernel.org>,
        <linux-kernel@vger.kernel.org>, <jack.zhu@starfivetech.com>,
        <changhuang.liang@starfivetech.com>
Subject: [PATCH v3 6/9] media: cadence: Add operation on reset
Date:   Fri, 31 Mar 2023 20:18:23 +0800
Message-ID: <20230331121826.96973-7-jack.zhu@starfivetech.com>
In-Reply-To: <20230331121826.96973-1-jack.zhu@starfivetech.com>
References: <20230331121826.96973-1-jack.zhu@starfivetech.com>
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Precedence: bulk

Add operation on reset for Cadence MIPI-CSI2 RX Controller.

Signed-off-by: Jack Zhu <jack.zhu@starfivetech.com>
---
 drivers/media/platform/cadence/cdns-csi2rx.c | 30 ++++++++++++++++++++
 1 file changed, 30 insertions(+)

diff --git a/drivers/media/platform/cadence/cdns-csi2rx.c b/drivers/media/platform/cadence/cdns-csi2rx.c
index cc3ebb0d96f6..a1555cedb349 100644
--- a/drivers/media/platform/cadence/cdns-csi2rx.c
+++ b/drivers/media/platform/cadence/cdns-csi2rx.c
@@ -13,6 +13,7 @@
 #include <linux/of_graph.h>
 #include <linux/phy/phy.h>
 #include <linux/platform_device.h>
+#include <linux/reset.h>
 #include <linux/slab.h>
 
 #include <media/v4l2-ctrls.h>
@@ -68,6 +69,9 @@ struct csi2rx_priv {
 	struct clk			*sys_clk;
 	struct clk			*p_clk;
 	struct clk			*pixel_clk[CSI2RX_STREAMS_MAX];
+	struct reset_control		*sys_rst;
+	struct reset_control		*p_rst;
+	struct reset_control		*pixel_rst[CSI2RX_STREAMS_MAX];
 	struct phy			*dphy;
 
 	u8				lanes[CSI2RX_LANES_MAX];
@@ -112,6 +116,7 @@ static int csi2rx_start(struct csi2rx_priv *csi2rx)
 	if (ret)
 		return ret;
 
+	reset_control_deassert(csi2rx->p_rst);
 	csi2rx_reset(csi2rx);
 
 	reg = csi2rx->num_lanes << 8;
@@ -154,6 +159,8 @@ static int csi2rx_start(struct csi2rx_priv *csi2rx)
 		if (ret)
 			goto err_disable_pixclk;
 
+		reset_control_deassert(csi2rx->pixel_rst[i]);
+
 		writel(CSI2RX_STREAM_CFG_FIFO_MODE_LARGE_BUF,
 		       csi2rx->base + CSI2RX_STREAM_CFG_REG(i));
 
@@ -169,6 +176,7 @@ static int csi2rx_start(struct csi2rx_priv *csi2rx)
 	if (ret)
 		goto err_disable_pixclk;
 
+	reset_control_deassert(csi2rx->sys_rst);
 	clk_disable_unprepare(csi2rx->p_clk);
 
 	return 0;
@@ -188,14 +196,17 @@ static void csi2rx_stop(struct csi2rx_priv *csi2rx)
 	unsigned int i;
 
 	clk_prepare_enable(csi2rx->p_clk);
+	reset_control_assert(csi2rx->sys_rst);
 	clk_disable_unprepare(csi2rx->sys_clk);
 
 	for (i = 0; i < csi2rx->max_streams; i++) {
 		writel(0, csi2rx->base + CSI2RX_STREAM_CTRL_REG(i));
 
+		reset_control_assert(csi2rx->pixel_rst[i]);
 		clk_disable_unprepare(csi2rx->pixel_clk[i]);
 	}
 
+	reset_control_assert(csi2rx->p_rst);
 	clk_disable_unprepare(csi2rx->p_clk);
 
 	if (v4l2_subdev_call(csi2rx->source_subdev, video, s_stream, false))
@@ -299,6 +310,17 @@ static int csi2rx_get_resources(struct csi2rx_priv *csi2rx,
 		return PTR_ERR(csi2rx->p_clk);
 	}
 
+	csi2rx->sys_rst =
+		devm_reset_control_get_optional_exclusive(&pdev->dev,
+							  "sys_rst");
+	if (IS_ERR(csi2rx->sys_rst))
+		return PTR_ERR(csi2rx->sys_rst);
+
+	csi2rx->p_rst =
+		devm_reset_control_get_optional_exclusive(&pdev->dev, "p_rst");
+	if (IS_ERR(csi2rx->p_rst))
+		return PTR_ERR(csi2rx->p_rst);
+
 	csi2rx->dphy = devm_phy_optional_get(&pdev->dev, "dphy");
 	if (IS_ERR(csi2rx->dphy)) {
 		dev_err(&pdev->dev, "Couldn't get external D-PHY\n");
@@ -350,6 +372,7 @@ static int csi2rx_get_resources(struct csi2rx_priv *csi2rx,
 
 	for (i = 0; i < csi2rx->max_streams; i++) {
 		char clk_name[16];
+		char rst_name[16];
 
 		snprintf(clk_name, sizeof(clk_name), "pixel_if%u_clk", i);
 		csi2rx->pixel_clk[i] = devm_clk_get(&pdev->dev, clk_name);
@@ -357,6 +380,13 @@ static int csi2rx_get_resources(struct csi2rx_priv *csi2rx,
 			dev_err(&pdev->dev, "Couldn't get clock %s\n", clk_name);
 			return PTR_ERR(csi2rx->pixel_clk[i]);
 		}
+
+		snprintf(rst_name, sizeof(rst_name), "pixel_if%u_rst", i);
+		csi2rx->pixel_rst[i] =
+			devm_reset_control_get_optional_exclusive(&pdev->dev,
+								  rst_name);
+		if (IS_ERR(csi2rx->pixel_rst[i]))
+			return PTR_ERR(csi2rx->pixel_rst[i]);
 	}
 
 	return 0;
-- 
2.34.1