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From: Julien Massot <julien.massot@collabora.com>
To: linux-media@vger.kernel.org
Cc: devicetree@vger.kernel.org,
	kernel@collabora.com,
	linux-kernel@vger.kernel.org,
	mchehab@kernel.org,
	robh+dt@kernel.org,
	krzysztof.kozlowski+dt@linaro.org,
	conor+dt@kernel.org,
	sakari.ailus@iki.fi,
	Julien Massot <julien.massot@collabora.com>
Subject: [PATCH v5 4/4] media: i2c: add MAX96714 driver
Date: Wed, 13 Mar 2024 10:49:22 +0100
Message-ID: <20240313094922.311743-5-julien.massot@collabora.com>
In-Reply-To: <20240313094922.311743-1-julien.massot@collabora.com>
References: <20240313094922.311743-1-julien.massot@collabora.com>
Precedence: bulk
MIME-Version: 1.0
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This driver handles the MAX96714 deserializer in tunnel mode.
The CSI output will replicate all the CSI traffic forwarded by
the remote serializer.

Signed-off-by: Julien Massot <julien.massot@collabora.com>
---
Change since v4:
 - make the driver compatible with MAX96714 instead of MAX96714F
 - Add the device id for the MAX96714

Change since v3:
 - Maintainers: align to the new binding path
 - Kconfig: better describe the symbol
 - Aligned the macro
 - Store the v4l2_mbus_config_mipi_csi2 structure instead of the full endpoint in the driver private structure
 - moved ret variables declaration at last
 - Removed extra new lines
 - Return the v4l2_subdev_set_routing_with_fmt result in _max96714_set_routing
 - Use v4l2_subdev_s_stream_helper instead of the custom max96714_s_stream function
 - Removed unnecessary check 'if (priv->tx_link_freq < 0)' in create_subdev since dt is already validated in max96714_parse_dt_txport
 - Use div_u64 to fix compilation on 32 bits platforms
 - Specify D-PHY for fwnode endpoint parsing since the MAX96714 only supports D-PHY
 - Simplify parse_dt function by parsing first the tx_port so that we no longer have to call fwnode_handle_put(priv->rxport.source.ep_fwnode);
 - Do not initialize regmap twice
 - Use unsigned int instead of u8

Change since v2:
 - Use CCI helpers instead of recoding register access
 - add missing bitfield header
 - Add pattern generator so the deserializer can be tested without a serializer/sensor
---
 MAINTAINERS                  |    7 +
 drivers/media/i2c/Kconfig    |   14 +
 drivers/media/i2c/Makefile   |    1 +
 drivers/media/i2c/max96714.c | 1029 ++++++++++++++++++++++++++++++++++
 4 files changed, 1051 insertions(+)
 create mode 100644 drivers/media/i2c/max96714.c

diff --git a/MAINTAINERS b/MAINTAINERS
index c97445b2483b..236267cc7d12 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -13181,6 +13181,13 @@ S:	Maintained
 F:	Documentation/devicetree/bindings/media/i2c/maxim,max96712.yaml
 F:	drivers/staging/media/max96712/max96712.c
 
+MAX96714 GMSL2 DESERIALIZER DRIVER
+M:	Julien Massot <julien.massot@collabora.com>
+L:	linux-media@vger.kernel.org
+S:	Maintained
+F:	Documentation/devicetree/bindings/media/i2c/maxim,max96714.yaml
+F:	drivers/media/i2c/max96714.c
+
 MAX96717 GMSL2 SERIALIZER DRIVER
 M:	Julien Massot <julien.massot@collabora.com>
 L:	linux-media@vger.kernel.org
diff --git a/drivers/media/i2c/Kconfig b/drivers/media/i2c/Kconfig
index 1a99396edbcf..64fc4c1c1fc1 100644
--- a/drivers/media/i2c/Kconfig
+++ b/drivers/media/i2c/Kconfig
@@ -1573,6 +1573,20 @@ config VIDEO_DS90UB960
 	  Device driver for the Texas Instruments DS90UB960
 	  FPD-Link III Deserializer and DS90UB9702 FPD-Link IV Deserializer.
 
+config VIDEO_MAX96714
+	tristate "Maxim MAX96714 GMSL2 deserializer"
+	depends on OF && I2C && VIDEO_DEV
+	select I2C_MUX
+	select GPIOLIB
+	select V4L2_CCI_I2C
+	help
+	  Device driver for the Maxim MAX96714 GMSL2 Deserializer.
+	  MAX96714 deserializers convert a GMSL2 input to MIPI CSI-2
+	  output.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called max96714.
+
 config VIDEO_MAX96717
 	tristate "Maxim MAX96717 GMSL2 Serializer support"
 	depends on OF && I2C && VIDEO_DEV && COMMON_CLK
diff --git a/drivers/media/i2c/Makefile b/drivers/media/i2c/Makefile
index 9e007116f929..7c794441eaff 100644
--- a/drivers/media/i2c/Makefile
+++ b/drivers/media/i2c/Makefile
@@ -64,6 +64,7 @@ obj-$(CONFIG_VIDEO_LM3646) += lm3646.o
 obj-$(CONFIG_VIDEO_M52790) += m52790.o
 obj-$(CONFIG_VIDEO_MAX9271_LIB) += max9271.o
 obj-$(CONFIG_VIDEO_MAX9286) += max9286.o
+obj-$(CONFIG_VIDEO_MAX96714) += max96714.o
 obj-$(CONFIG_VIDEO_MAX96717) += max96717.o
 obj-$(CONFIG_VIDEO_ML86V7667) += ml86v7667.o
 obj-$(CONFIG_VIDEO_MSP3400) += msp3400.o
diff --git a/drivers/media/i2c/max96714.c b/drivers/media/i2c/max96714.c
new file mode 100644
index 000000000000..32c1dc6b81a0
--- /dev/null
+++ b/drivers/media/i2c/max96714.c
@@ -0,0 +1,1029 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Maxim GMSL2 Deserializer Driver
+ *
+ * Copyright (C) 2024 Collabora Ltd.
+ */
+
+#include <linux/bitfield.h>
+#include <linux/bitops.h>
+#include <linux/fwnode.h>
+#include <linux/gpio/consumer.h>
+#include <linux/i2c.h>
+#include <linux/i2c-mux.h>
+#include <linux/module.h>
+#include <linux/regmap.h>
+#include <linux/regulator/consumer.h>
+
+#include <media/v4l2-cci.h>
+#include <media/v4l2-ctrls.h>
+#include <media/v4l2-fwnode.h>
+#include <media/v4l2-subdev.h>
+
+#define MAX96714_DEVICE_ID  0xc9
+#define MAX96714F_DEVICE_ID 0xca
+#define MAX96714_NPORTS     2
+#define MAX96714_PAD_SINK   0
+#define MAX96714_PAD_SOURCE 1
+
+/* DEV */
+#define MAX96714_REG13                 CCI_REG8(0x0d)
+#define MAX96714_DEV_REV               CCI_REG8(0x0e)
+#define MAX96714_DEV_REV_MASK          GENMASK(3, 0)
+#define MAX96714_LINK_LOCK             CCI_REG8(0x13)
+#define MAX96714_LINK_LOCK_BIT         BIT(3)
+#define MAX96714_IO_CHK0               CCI_REG8(0x38)
+#define MAX96714_PATTERN_CLK_FREQ      GENMASK(1, 0)
+/* VID_RX */
+#define MAX96714_VIDEO_RX8             CCI_REG8(0x11a)
+#define MAX96714_VID_LOCK              BIT(6)
+
+/* VRX_PATGEN_0 */
+#define MAX96714_PATGEN_0              CCI_REG8(0x240)
+#define MAX96714_PATGEN_1              CCI_REG8(0x241)
+#define MAX96714_PATGEN_MODE           GENMASK(5, 4)
+#define MAX96714_PATGEN_VS_DLY         CCI_REG24(0x242)
+#define MAX96714_PATGEN_VS_HIGH        CCI_REG24(0x245)
+#define MAX96714_PATGEN_VS_LOW         CCI_REG24(0x248)
+#define MAX96714_PATGEN_V2H            CCI_REG24(0x24b)
+#define MAX96714_PATGEN_HS_HIGH        CCI_REG16(0x24e)
+#define MAX96714_PATGEN_HS_LOW         CCI_REG16(0x250)
+#define MAX96714_PATGEN_HS_CNT         CCI_REG16(0x252)
+#define MAX96714_PATGEN_V2D            CCI_REG24(0x254)
+#define MAX96714_PATGEN_DE_HIGH        CCI_REG16(0x257)
+#define MAX96714_PATGEN_DE_LOW         CCI_REG16(0x259)
+#define MAX96714_PATGEN_DE_CNT         CCI_REG16(0x25B)
+#define MAX96714_PATGEN_GRAD_INC       CCI_REG8(0x25d)
+#define MAX96714_PATGEN_CHKB_COLOR_A   CCI_REG24(0x25E)
+#define MAX96714_PATGEN_CHKB_COLOR_B   CCI_REG24(0x261)
+#define MAX96714_PATGEN_CHKB_RPT_CNT_A CCI_REG8(0x264)
+#define MAX96714_PATGEN_CHKB_RPT_CNT_B CCI_REG8(0x265)
+#define MAX96714_PATGEN_CHKB_ALT       CCI_REG8(0x266)
+/* BACKTOP */
+#define MAX96714_BACKTOP25             CCI_REG8(0x320)
+#define CSI_DPLL_FREQ_MASK             GENMASK(4, 0)
+
+/* MIPI_PHY */
+#define MAX96714_MIPI_PHY0             CCI_REG8(0x330)
+#define MAX96714_FORCE_CSI_OUT         BIT(7)
+#define MAX96714_MIPI_STDBY_N          CCI_REG8(0x332)
+#define MAX96714_MIPI_STDBY_MASK       GENMASK(5, 4)
+#define MAX96714_MIPI_LANE_MAP         CCI_REG8(0x333)
+#define MAX96714_MIPI_POLARITY         CCI_REG8(0x335)
+#define MAX96714_MIPI_POLARITY_MASK    GENMASK(5, 0)
+
+/* MIPI_TX */
+#define MAX96714_MIPI_LANE_CNT         CCI_REG8(0x44a)
+#define MAX96714_CSI2_LANE_CNT_MASK    GENMASK(7, 6)
+#define MAX96714_MIPI_TX52             CCI_REG8(0x474)
+#define MAX96714_TUN_EN                BIT(0)
+
+#define MHZ(v) ((u32)((v)  * 1000000U))
+
+enum max96714_vpg_mode {
+	MAX96714_VPG_DISABLED = 0,
+	MAX96714_VPG_CHECKERBOARD = 1,
+	MAX96714_VPG_GRADIENT = 2,
+};
+
+struct max96714_rxport {
+	struct {
+		struct v4l2_subdev   *sd;
+		u16                  pad;
+		struct fwnode_handle *ep_fwnode;
+	} source;
+	struct regulator	     *poc;
+};
+
+struct max96714_txport {
+	struct v4l2_fwnode_endpoint vep;
+};
+
+struct max96714_priv {
+	struct i2c_client                 *client;
+	struct regmap                     *regmap;
+	struct gpio_desc                  *pd_gpio;
+	struct max96714_rxport            rxport;
+	struct i2c_mux_core               *mux;
+	u64                               enabled_source_streams;
+	struct v4l2_subdev		  sd;
+	struct media_pad		  pads[MAX96714_NPORTS];
+	struct v4l2_mbus_config_mipi_csi2 mipi_csi2;
+	struct v4l2_ctrl_handler          ctrl_handler;
+	struct v4l2_async_notifier        notifier;
+	s64                               tx_link_freq;
+	enum max96714_vpg_mode            pattern;
+};
+
+static inline struct max96714_priv *sd_to_max96714(struct v4l2_subdev *sd)
+{
+	return container_of(sd, struct max96714_priv, sd);
+}
+
+static int max96714_enable_tx_port(struct max96714_priv *priv)
+{
+	return cci_update_bits(priv->regmap, MAX96714_MIPI_STDBY_N,
+			       MAX96714_MIPI_STDBY_MASK,
+			       MAX96714_MIPI_STDBY_MASK, NULL);
+}
+
+static int max96714_disable_tx_port(struct max96714_priv *priv)
+{
+	return cci_update_bits(priv->regmap, MAX96714_MIPI_STDBY_N,
+			       MAX96714_MIPI_STDBY_MASK, 0, NULL);
+}
+
+static bool max96714_tx_port_enabled(struct max96714_priv *priv)
+{
+	u64 val;
+
+	cci_read(priv->regmap, MAX96714_MIPI_STDBY_N, &val, NULL);
+
+	return val & MAX96714_MIPI_STDBY_MASK;
+}
+
+static int max96714_apply_patgen_timing(struct max96714_priv *priv,
+					struct v4l2_subdev_state *state)
+{
+	struct v4l2_mbus_framefmt *fmt =
+		v4l2_subdev_state_get_format(state, MAX96714_PAD_SOURCE);
+	const u32 h_active = fmt->width;
+	const u32 h_fp = 88;
+	const u32 h_sw = 44;
+	const u32 h_bp = 148;
+	u32 h_tot;
+
+	const u32 v_active = fmt->height;
+	const u32 v_fp = 4;
+	const u32 v_sw = 5;
+	const u32 v_bp = 36;
+	u32 v_tot;
+	int ret = 0;
+
+	h_tot = h_active + h_fp + h_sw + h_bp;
+	v_tot = v_active + v_fp + v_sw + v_bp;
+
+	/* 75 Mhz pixel clock */
+	cci_update_bits(priv->regmap, MAX96714_IO_CHK0,
+			MAX96714_PATTERN_CLK_FREQ, 1, &ret);
+
+	dev_info(&priv->client->dev, "height: %d width: %d\n", fmt->height,
+		 fmt->width);
+
+	cci_write(priv->regmap, MAX96714_PATGEN_VS_DLY, 0, &ret);
+	cci_write(priv->regmap, MAX96714_PATGEN_VS_HIGH, v_sw * h_tot, &ret);
+	cci_write(priv->regmap, MAX96714_PATGEN_VS_LOW,
+		  (v_active + v_fp + v_bp) * h_tot, &ret);
+	cci_write(priv->regmap, MAX96714_PATGEN_HS_HIGH, h_sw, &ret);
+	cci_write(priv->regmap, MAX96714_PATGEN_HS_LOW, h_active + h_fp + h_bp,
+		  &ret);
+	cci_write(priv->regmap, MAX96714_PATGEN_V2D,
+		  h_tot * (v_sw + v_bp) + (h_sw + h_bp), &ret);
+	cci_write(priv->regmap, MAX96714_PATGEN_HS_CNT, v_tot, &ret);
+	cci_write(priv->regmap, MAX96714_PATGEN_DE_HIGH, h_active, &ret);
+	cci_write(priv->regmap, MAX96714_PATGEN_DE_LOW, h_fp + h_sw + h_bp,
+		  &ret);
+	cci_write(priv->regmap, MAX96714_PATGEN_DE_CNT, v_active, &ret);
+	/* B G R */
+	cci_write(priv->regmap, MAX96714_PATGEN_CHKB_COLOR_A, 0xfecc00, &ret);
+	/* B G R */
+	cci_write(priv->regmap, MAX96714_PATGEN_CHKB_COLOR_B, 0x006aa7, &ret);
+	cci_write(priv->regmap, MAX96714_PATGEN_CHKB_RPT_CNT_A, 0x3c, &ret);
+	cci_write(priv->regmap, MAX96714_PATGEN_CHKB_RPT_CNT_B, 0x3c, &ret);
+	cci_write(priv->regmap, MAX96714_PATGEN_CHKB_ALT, 0x3c, &ret);
+	cci_write(priv->regmap, MAX96714_PATGEN_GRAD_INC, 0x10, &ret);
+
+	return ret;
+}
+
+static int max96714_apply_patgen(struct max96714_priv *priv,
+				 struct v4l2_subdev_state *state)
+{
+	unsigned int val;
+	int ret = 0;
+
+	if (priv->pattern)
+		ret = max96714_apply_patgen_timing(priv, state);
+
+	cci_write(priv->regmap, MAX96714_PATGEN_0, priv->pattern ? 0xfb : 0,
+		  &ret);
+
+	val = FIELD_PREP(MAX96714_PATGEN_MODE, priv->pattern);
+	cci_update_bits(priv->regmap, MAX96714_PATGEN_1, MAX96714_PATGEN_MODE,
+			val, &ret);
+	return ret;
+}
+
+static int max96714_s_ctrl(struct v4l2_ctrl *ctrl)
+{
+	struct max96714_priv *priv =
+		container_of(ctrl->handler, struct max96714_priv, ctrl_handler);
+	int ret;
+
+	switch (ctrl->id) {
+	case V4L2_CID_TEST_PATTERN:
+		priv->pattern = ctrl->val;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	ret = cci_update_bits(priv->regmap, MAX96714_MIPI_PHY0,
+			      MAX96714_FORCE_CSI_OUT,
+			      priv->pattern ? MAX96714_FORCE_CSI_OUT : 0, NULL);
+
+	/* Pattern generator doesn't work with tunnel mode */
+	return cci_update_bits(priv->regmap, MAX96714_MIPI_TX52,
+			       MAX96714_TUN_EN,
+			       priv->pattern ? 0 : MAX96714_TUN_EN, &ret);
+}
+
+static const char * const max96714_test_pattern[] = {
+	"Disabled",
+	"Checkerboard",
+	"Gradient"
+};
+
+static const struct v4l2_ctrl_ops max96714_ctrl_ops = {
+	.s_ctrl = max96714_s_ctrl,
+};
+
+static int max96714_enable_streams(struct v4l2_subdev *sd,
+				   struct v4l2_subdev_state *state,
+				   u32 source_pad, u64 streams_mask)
+{
+	struct max96714_priv *priv = sd_to_max96714(sd);
+	u64 sink_streams;
+	int ret;
+
+	if (!priv->enabled_source_streams)
+		max96714_enable_tx_port(priv);
+
+	ret = max96714_apply_patgen(priv, state);
+	if (ret)
+		goto err;
+
+	if (!priv->pattern) {
+		if (!priv->rxport.source.sd) {
+			ret = -ENODEV;
+			goto err;
+		}
+
+		sink_streams =
+			v4l2_subdev_state_xlate_streams(state,
+							MAX96714_PAD_SOURCE,
+							MAX96714_PAD_SINK,
+							&streams_mask);
+
+		ret = v4l2_subdev_enable_streams(priv->rxport.source.sd,
+						 priv->rxport.source.pad,
+						 sink_streams);
+		if (ret)
+			goto err;
+	}
+
+	priv->enabled_source_streams |= streams_mask;
+
+	return 0;
+
+err:
+	if (!priv->enabled_source_streams)
+		max96714_disable_tx_port(priv);
+
+	return ret;
+}
+
+static int max96714_disable_streams(struct v4l2_subdev *sd,
+				    struct v4l2_subdev_state *state,
+				    u32 source_pad, u64 streams_mask)
+{
+	struct max96714_priv *priv = sd_to_max96714(sd);
+	u64 sink_streams;
+	int ret;
+
+	if (!priv->pattern && priv->rxport.source.sd) {
+		sink_streams =
+			v4l2_subdev_state_xlate_streams(state,
+							MAX96714_PAD_SOURCE,
+							MAX96714_PAD_SINK,
+							&streams_mask);
+
+		ret = v4l2_subdev_disable_streams(priv->rxport.source.sd,
+						  priv->rxport.source.pad,
+						  sink_streams);
+		if (ret)
+			return ret;
+	}
+
+	priv->enabled_source_streams &= ~streams_mask;
+
+	if (!priv->enabled_source_streams)
+		max96714_disable_tx_port(priv);
+
+	return 0;
+}
+
+static int max96714_set_fmt(struct v4l2_subdev *sd,
+			    struct v4l2_subdev_state *state,
+			    struct v4l2_subdev_format *format)
+{
+	struct max96714_priv *priv = sd_to_max96714(sd);
+	struct v4l2_mbus_framefmt *fmt;
+
+	if (format->which == V4L2_SUBDEV_FORMAT_ACTIVE &&
+	    priv->enabled_source_streams)
+		return -EBUSY;
+
+	/* No transcoding, source and sink formats must match. */
+	if (format->pad == MAX96714_PAD_SOURCE)
+		return v4l2_subdev_get_fmt(sd, state, format);
+
+	fmt = v4l2_subdev_state_get_format(state, format->pad, format->stream);
+	if (!fmt)
+		return -EINVAL;
+
+	*fmt = format->format;
+
+	fmt = v4l2_subdev_state_get_opposite_stream_format(state, format->pad,
+							   format->stream);
+	if (!fmt)
+		return -EINVAL;
+
+	*fmt = format->format;
+
+	return 0;
+}
+
+static int _max96714_set_routing(struct v4l2_subdev *sd,
+				 struct v4l2_subdev_state *state,
+				 enum v4l2_subdev_format_whence which,
+				 struct v4l2_subdev_krouting *routing)
+{
+	static const struct v4l2_mbus_framefmt format = {
+		.width = 1280,
+		.height = 1080,
+		.code = MEDIA_BUS_FMT_Y8_1X8,
+		.field = V4L2_FIELD_NONE,
+	};
+	int ret;
+
+	/*
+	 * Note: we can only support up to V4L2_FRAME_DESC_ENTRY_MAX, until
+	 * frame desc is made dynamically allocated.
+	 */
+	if (routing->num_routes > V4L2_FRAME_DESC_ENTRY_MAX)
+		return -EINVAL;
+
+	ret = v4l2_subdev_routing_validate(sd, routing,
+					   V4L2_SUBDEV_ROUTING_ONLY_1_TO_1);
+	if (ret)
+		return ret;
+
+	return v4l2_subdev_set_routing_with_fmt(sd, state, routing, &format);
+}
+
+static int max96714_set_routing(struct v4l2_subdev *sd,
+				struct v4l2_subdev_state *state,
+				enum v4l2_subdev_format_whence which,
+				struct v4l2_subdev_krouting *routing)
+{
+	struct max96714_priv *priv = sd_to_max96714(sd);
+
+	if (which == V4L2_SUBDEV_FORMAT_ACTIVE && priv->enabled_source_streams)
+		return -EBUSY;
+
+	return _max96714_set_routing(sd, state, which, routing);
+}
+
+static int max96714_init_state(struct v4l2_subdev *sd,
+			       struct v4l2_subdev_state *state)
+{
+	struct v4l2_subdev_route routes[] = {
+		{
+			.sink_pad = MAX96714_PAD_SINK,
+			.sink_stream = 0,
+			.source_pad = MAX96714_PAD_SOURCE,
+			.source_stream = 0,
+			.flags = V4L2_SUBDEV_ROUTE_FL_ACTIVE,
+		}
+	};
+	struct v4l2_subdev_krouting routing = {
+		.num_routes = ARRAY_SIZE(routes),
+		.routes = routes,
+	};
+
+	return _max96714_set_routing(sd, state, V4L2_SUBDEV_FORMAT_ACTIVE,
+				     &routing);
+}
+
+static const struct v4l2_subdev_pad_ops max96714_pad_ops = {
+	.enable_streams = max96714_enable_streams,
+	.disable_streams = max96714_disable_streams,
+
+	.set_routing = max96714_set_routing,
+	.get_fmt = v4l2_subdev_get_fmt,
+	.set_fmt = max96714_set_fmt,
+};
+
+static bool max96714_link_locked(struct max96714_priv *priv)
+{
+	u64 val = 0;
+
+	cci_read(priv->regmap, MAX96714_LINK_LOCK, &val, NULL);
+
+	return val & MAX96714_LINK_LOCK_BIT;
+}
+
+static void max96714_link_status(struct max96714_priv *priv)
+{
+	struct device *dev = &priv->client->dev;
+
+	dev_info(dev, "Link locked:%d\n", max96714_link_locked(priv));
+}
+
+static bool max96714_pipe_locked(struct max96714_priv *priv)
+{
+	u64 val;
+
+	cci_read(priv->regmap, MAX96714_VIDEO_RX8, &val, NULL);
+
+	return val & MAX96714_VID_LOCK;
+}
+
+static void max96714_pipe_status(struct max96714_priv *priv)
+{
+	struct device *dev = &priv->client->dev;
+
+	dev_info(dev, "Pipe vidlock:%d\n", max96714_pipe_locked(priv));
+}
+
+static void max96714_csi_status(struct max96714_priv *priv)
+{
+	struct device *dev = &priv->client->dev;
+	u64 freq = 0;
+
+	cci_read(priv->regmap, MAX96714_BACKTOP25, &freq, NULL);
+	freq = FIELD_GET(CSI_DPLL_FREQ_MASK, freq);
+
+	dev_info(dev, "CSI controller DPLL freq:%u00MHz CSIPHY enabled:%d\n",
+		 (u8)freq, max96714_tx_port_enabled(priv));
+}
+
+static int max96714_log_status(struct v4l2_subdev *sd)
+{
+	struct max96714_priv *priv = sd_to_max96714(sd);
+	struct device *dev = &priv->client->dev;
+
+	dev_info(dev, "Deserializer: max96714\n");
+
+	max96714_link_status(priv);
+	max96714_pipe_status(priv);
+	max96714_csi_status(priv);
+
+	return 0;
+}
+
+static const struct v4l2_subdev_core_ops max96714_subdev_core_ops = {
+	.log_status = max96714_log_status,
+};
+
+static const struct v4l2_subdev_video_ops max96714_video_ops = {
+	.s_stream	= v4l2_subdev_s_stream_helper,
+};
+
+static const struct v4l2_subdev_internal_ops max96714_internal_ops = {
+	.init_state = max96714_init_state,
+};
+
+static const struct v4l2_subdev_ops max96714_subdev_ops = {
+	.video = &max96714_video_ops,
+	.core = &max96714_subdev_core_ops,
+	.pad = &max96714_pad_ops,
+};
+
+static const struct media_entity_operations max96714_entity_ops = {
+	.link_validate = v4l2_subdev_link_validate,
+};
+
+static int max96714_notify_bound(struct v4l2_async_notifier *notifier,
+				 struct v4l2_subdev *subdev,
+				 struct v4l2_async_connection *asd)
+{
+	struct max96714_priv *priv = sd_to_max96714(notifier->sd);
+	struct device *dev = &priv->client->dev;
+	int ret;
+
+	ret = media_entity_get_fwnode_pad(&subdev->entity,
+					  priv->rxport.source.ep_fwnode,
+					  MEDIA_PAD_FL_SOURCE);
+	if (ret < 0) {
+		dev_err(dev, "Failed to find pad for %s\n", subdev->name);
+		return ret;
+	}
+
+	priv->rxport.source.sd = subdev;
+	priv->rxport.source.pad = ret;
+
+	ret = media_create_pad_link(&priv->rxport.source.sd->entity,
+				    priv->rxport.source.pad, &priv->sd.entity,
+				    MAX96714_PAD_SINK,
+				    MEDIA_LNK_FL_ENABLED |
+				    MEDIA_LNK_FL_IMMUTABLE);
+	if (ret) {
+		dev_err(dev, "Unable to link %s:%u -> %s:%u\n",
+			priv->rxport.source.sd->name, priv->rxport.source.pad,
+			priv->sd.name, MAX96714_PAD_SINK);
+		return ret;
+	}
+
+	return 0;
+}
+
+static const struct v4l2_async_notifier_operations max96714_notify_ops = {
+	.bound = max96714_notify_bound,
+};
+
+static int max96714_v4l2_notifier_register(struct max96714_priv *priv)
+{
+	struct device *dev = &priv->client->dev;
+	struct max96714_rxport *rxport = &priv->rxport;
+	struct v4l2_async_connection *asd;
+	int ret;
+
+	if (!rxport->source.ep_fwnode)
+		return 0;
+
+	v4l2_async_subdev_nf_init(&priv->notifier, &priv->sd);
+
+	asd = v4l2_async_nf_add_fwnode(&priv->notifier,
+				       rxport->source.ep_fwnode,
+				       struct v4l2_async_connection);
+	if (IS_ERR(asd)) {
+		dev_err(dev, "Failed to add subdev: %pe", asd);
+		v4l2_async_nf_cleanup(&priv->notifier);
+		return PTR_ERR(asd);
+	}
+
+	priv->notifier.ops = &max96714_notify_ops;
+
+	ret = v4l2_async_nf_register(&priv->notifier);
+	if (ret) {
+		dev_err(dev, "Failed to register subdev_notifier");
+		v4l2_async_nf_cleanup(&priv->notifier);
+		return ret;
+	}
+
+	return 0;
+}
+
+static void max96714_v4l2_notifier_unregister(struct max96714_priv *priv)
+{
+	v4l2_async_nf_unregister(&priv->notifier);
+	v4l2_async_nf_cleanup(&priv->notifier);
+}
+
+static int max96714_create_subdev(struct max96714_priv *priv)
+{
+	struct device *dev = &priv->client->dev;
+	int ret;
+
+	v4l2_i2c_subdev_init(&priv->sd, priv->client, &max96714_subdev_ops);
+	priv->sd.internal_ops = &max96714_internal_ops;
+
+	v4l2_ctrl_handler_init(&priv->ctrl_handler, 1);
+	priv->sd.ctrl_handler = &priv->ctrl_handler;
+
+	v4l2_ctrl_new_int_menu(&priv->ctrl_handler, NULL, V4L2_CID_LINK_FREQ,
+			       0, 0, &priv->tx_link_freq);
+	if (priv->ctrl_handler.error) {
+		ret = priv->ctrl_handler.error;
+		goto err_free_ctrl;
+	}
+
+	v4l2_ctrl_new_std_menu_items(&priv->ctrl_handler,
+				     &max96714_ctrl_ops,
+				     V4L2_CID_TEST_PATTERN,
+				     ARRAY_SIZE(max96714_test_pattern) - 1,
+				     0, 0, max96714_test_pattern);
+	if (priv->ctrl_handler.error) {
+		ret = priv->ctrl_handler.error;
+		goto err_free_ctrl;
+	}
+
+	priv->sd.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE | V4L2_SUBDEV_FL_STREAMS;
+	priv->sd.entity.function = MEDIA_ENT_F_VID_IF_BRIDGE;
+	priv->sd.entity.ops = &max96714_entity_ops;
+
+	priv->pads[MAX96714_PAD_SINK].flags = MEDIA_PAD_FL_SINK;
+	priv->pads[MAX96714_PAD_SOURCE].flags = MEDIA_PAD_FL_SOURCE;
+
+	ret = media_entity_pads_init(&priv->sd.entity,
+				     MAX96714_NPORTS,
+				     priv->pads);
+	if (ret)
+		goto err_free_ctrl;
+
+	priv->sd.state_lock = priv->sd.ctrl_handler->lock;
+
+	ret = v4l2_subdev_init_finalize(&priv->sd);
+	if (ret)
+		goto err_entity_cleanup;
+
+	ret = max96714_v4l2_notifier_register(priv);
+	if (ret) {
+		dev_err(dev, "v4l2 subdev notifier register failed: %d\n", ret);
+		goto err_subdev_cleanup;
+	}
+
+	ret = v4l2_async_register_subdev(&priv->sd);
+	if (ret) {
+		dev_err(dev, "v4l2_async_register_subdev error: %d\n", ret);
+		goto err_unreg_notif;
+	}
+
+	return 0;
+
+err_unreg_notif:
+	max96714_v4l2_notifier_unregister(priv);
+err_subdev_cleanup:
+	v4l2_subdev_cleanup(&priv->sd);
+err_entity_cleanup:
+	media_entity_cleanup(&priv->sd.entity);
+err_free_ctrl:
+	v4l2_ctrl_handler_free(&priv->ctrl_handler);
+
+	return ret;
+};
+
+static void max96714_destroy_subdev(struct max96714_priv *priv)
+{
+	max96714_v4l2_notifier_unregister(priv);
+	v4l2_async_unregister_subdev(&priv->sd);
+
+	v4l2_subdev_cleanup(&priv->sd);
+
+	media_entity_cleanup(&priv->sd.entity);
+	v4l2_ctrl_handler_free(&priv->ctrl_handler);
+}
+
+static int max96714_i2c_mux_select(struct i2c_mux_core *mux, u32 chan)
+{
+	return 0;
+}
+
+static int max96714_i2c_mux_init(struct max96714_priv *priv)
+{
+	priv->mux = i2c_mux_alloc(priv->client->adapter, &priv->client->dev,
+				  1, 0, I2C_MUX_LOCKED | I2C_MUX_GATE,
+				  max96714_i2c_mux_select, NULL);
+	if (!priv->mux)
+		return -ENOMEM;
+
+	return i2c_mux_add_adapter(priv->mux, 0, 0, 0);
+}
+
+static int max96714_init_tx_port(struct max96714_priv *priv)
+{
+	struct v4l2_mbus_config_mipi_csi2 *mipi;
+	unsigned long lanes_used = 0;
+	unsigned int val, lane;
+	int ret;
+
+	ret = max96714_disable_tx_port(priv);
+
+	mipi = &priv->mipi_csi2;
+	val = div_u64(priv->tx_link_freq * 2, MHZ(100));
+
+	cci_update_bits(priv->regmap, MAX96714_BACKTOP25,
+			CSI_DPLL_FREQ_MASK, val, &ret);
+
+	val = FIELD_PREP(MAX96714_CSI2_LANE_CNT_MASK, mipi->num_data_lanes - 1);
+	cci_update_bits(priv->regmap, MAX96714_MIPI_LANE_CNT,
+			MAX96714_CSI2_LANE_CNT_MASK, val, &ret);
+
+	/* lanes polarity */
+	val = 0;
+	for (lane = 0; lane < mipi->num_data_lanes + 1; lane++) {
+		if (!mipi->lane_polarities[lane])
+			continue;
+		if (lane == 0)
+			/* clock lane */
+			val |= BIT(5);
+		else if (lane < 3)
+			/* Lane D0 and D1 */
+			val |= BIT(lane - 1);
+		else
+			/* D2 and D3 */
+			val |= BIT(lane);
+	}
+
+	cci_update_bits(priv->regmap, MAX96714_MIPI_POLARITY,
+			MAX96714_MIPI_POLARITY_MASK, val, &ret);
+
+	/* lanes mapping */
+	val = 0;
+	for (lane = 0; lane < mipi->num_data_lanes; lane++) {
+		val |= (mipi->data_lanes[lane] - 1) << (lane * 2);
+		lanes_used |= BIT(mipi->data_lanes[lane] - 1);
+	}
+
+	/* Unused lanes need to be mapped as well to not have
+	 * the same lanes mapped twice.
+	 */
+	for (; lane < 4; lane++) {
+		unsigned int idx = find_first_zero_bit(&lanes_used, 4);
+
+		val |= idx << (lane * 2);
+		lanes_used |= BIT(idx);
+	}
+
+	return cci_write(priv->regmap, MAX96714_MIPI_LANE_MAP, val, &ret);
+}
+
+static int max96714_rxport_enable_poc(struct max96714_priv *priv)
+{
+	struct max96714_rxport *rxport = &priv->rxport;
+
+	if (!rxport->poc)
+		return 0;
+
+	return regulator_enable(rxport->poc);
+}
+
+static int max96714_rxport_disable_poc(struct max96714_priv *priv)
+{
+	struct max96714_rxport *rxport = &priv->rxport;
+
+	if (!rxport->poc)
+		return 0;
+
+	return regulator_disable(rxport->poc);
+}
+
+static int max96714_parse_dt_txport(struct max96714_priv *priv)
+{
+	struct device *dev = &priv->client->dev;
+	struct v4l2_fwnode_endpoint vep = {
+		.bus_type = V4L2_MBUS_CSI2_DPHY
+	};
+	struct fwnode_handle *ep_fwnode;
+	u32 num_data_lanes;
+	int ret;
+
+	ep_fwnode = fwnode_graph_get_endpoint_by_id(dev_fwnode(dev),
+						    MAX96714_PAD_SOURCE, 0, 0);
+	if (!ep_fwnode)
+		return -EINVAL;
+
+	ret = v4l2_fwnode_endpoint_alloc_parse(ep_fwnode, &vep);
+	fwnode_handle_put(ep_fwnode);
+	if (ret) {
+		dev_err(dev, "tx: failed to parse endpoint data\n");
+		return -EINVAL;
+	}
+
+	if (vep.nr_of_link_frequencies != 1) {
+		ret = -EINVAL;
+		goto err_free_vep;
+	}
+
+	priv->tx_link_freq = vep.link_frequencies[0];
+	/* Min 50MHz, Max 1250MHz, 50MHz step */
+	if (priv->tx_link_freq < MHZ(50) || priv->tx_link_freq > MHZ(1250) ||
+	    (u32)priv->tx_link_freq % MHZ(50)) {
+		dev_err(dev, "tx: invalid link frequency\n");
+		ret = -EINVAL;
+		goto err_free_vep;
+	}
+
+	num_data_lanes = vep.bus.mipi_csi2.num_data_lanes;
+	if (num_data_lanes < 1 || num_data_lanes > 4) {
+		dev_err(dev,
+			"tx: invalid number of data lanes must be 1 to 4\n");
+		ret = -EINVAL;
+		goto err_free_vep;
+	}
+
+	memcpy(&priv->mipi_csi2, &vep.bus.mipi_csi2, sizeof(priv->mipi_csi2));
+
+err_free_vep:
+	v4l2_fwnode_endpoint_free(&vep);
+
+	return ret;
+};
+
+static int max96714_parse_dt_rxport(struct max96714_priv *priv)
+{
+	static const char *poc_name = "port0-poc";
+	struct max96714_rxport *rxport = &priv->rxport;
+	struct device *dev = &priv->client->dev;
+	struct fwnode_handle *ep_fwnode;
+	int ret;
+
+	ep_fwnode = fwnode_graph_get_endpoint_by_id(dev_fwnode(dev),
+						    MAX96714_PAD_SINK, 0, 0);
+	if (!ep_fwnode)
+		return -ENOENT;
+
+	rxport->source.ep_fwnode = fwnode_graph_get_remote_endpoint(ep_fwnode);
+	fwnode_handle_put(ep_fwnode);
+
+	if (!rxport->source.ep_fwnode) {
+		dev_err(dev, "rx: no remote endpoint\n");
+		return -EINVAL;
+	}
+
+	rxport->poc = devm_regulator_get_optional(dev, poc_name);
+	if (IS_ERR(rxport->poc)) {
+		ret = PTR_ERR(rxport->poc);
+		if (ret == -ENODEV) {
+			rxport->poc = NULL;
+		} else {
+			dev_err(dev, "rx: failed to get POC supply: %d\n", ret);
+			goto err_put_source_ep_fwnode;
+		}
+	}
+
+	return 0;
+
+err_put_source_ep_fwnode:
+	fwnode_handle_put(rxport->source.ep_fwnode);
+	return ret;
+}
+
+static int max96714_parse_dt(struct max96714_priv *priv)
+{
+	int ret;
+
+	ret = max96714_parse_dt_txport(priv);
+	if (ret)
+		return ret;
+
+	ret = max96714_parse_dt_rxport(priv);
+	/* The deserializer can create a test pattern even if the
+	 * rx port is not connected to a serializer.
+	 */
+	if (ret && ret == -ENOENT)
+		ret = 0;
+
+	return ret;
+}
+
+static int max96714_enable_core_hw(struct max96714_priv *priv)
+{
+	struct device *dev = &priv->client->dev;
+	u64 val;
+	int ret;
+
+	if (priv->pd_gpio) {
+		/* wait min 2 ms for reset to complete */
+		gpiod_set_value_cansleep(priv->pd_gpio, 1);
+		fsleep(2000);
+		gpiod_set_value_cansleep(priv->pd_gpio, 0);
+		/* wait min 2 ms for power up to finish */
+		fsleep(2000);
+	}
+
+	ret = cci_read(priv->regmap, MAX96714_REG13, &val, NULL);
+	if (ret) {
+		dev_err_probe(dev, ret, "Cannot read first register, abort\n");
+		goto err_pd_gpio;
+	}
+
+	if (val != MAX96714_DEVICE_ID && val != MAX96714F_DEVICE_ID) {
+		dev_err(dev, "Unsupported device id expected %x got %x\n",
+			MAX96714F_DEVICE_ID, (u8)val);
+		ret = -EOPNOTSUPP;
+		goto err_pd_gpio;
+	}
+
+	ret = cci_read(priv->regmap, MAX96714_DEV_REV, &val, NULL);
+	if (ret)
+		goto err_pd_gpio;
+
+	dev_dbg(dev, "Found %x (rev %lx)\n", MAX96714F_DEVICE_ID,
+		(u8)val & MAX96714_DEV_REV_MASK);
+
+	ret = cci_read(priv->regmap, MAX96714_MIPI_TX52, &val, NULL);
+	if (ret)
+		goto err_pd_gpio;
+
+	if (!(val & MAX96714_TUN_EN)) {
+		dev_err(dev, "Only supporting tunnel mode");
+		ret = -EOPNOTSUPP;
+		goto err_pd_gpio;
+	}
+
+	return 0;
+
+err_pd_gpio:
+	gpiod_set_value_cansleep(priv->pd_gpio, 1);
+	return ret;
+}
+
+static void max96714_disable_core_hw(struct max96714_priv *priv)
+{
+	gpiod_set_value_cansleep(priv->pd_gpio, 1);
+}
+
+static int max96714_get_hw_resources(struct max96714_priv *priv)
+{
+	struct device *dev = &priv->client->dev;
+
+	priv->regmap = devm_cci_regmap_init_i2c(priv->client, 16);
+	if (IS_ERR(priv->regmap))
+		return PTR_ERR(priv->regmap);
+
+	priv->pd_gpio =
+		devm_gpiod_get_optional(dev, "powerdown", GPIOD_OUT_HIGH);
+	if (IS_ERR(priv->pd_gpio))
+		return dev_err_probe(dev, PTR_ERR(priv->pd_gpio),
+				     "Cannot get powerdown GPIO\n");
+	return 0;
+}
+
+static int max96714_probe(struct i2c_client *client)
+{
+	struct device *dev = &client->dev;
+	struct max96714_priv *priv;
+	int ret;
+
+	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	priv->client = client;
+
+	ret = max96714_get_hw_resources(priv);
+	if (ret)
+		return ret;
+
+	ret = max96714_enable_core_hw(priv);
+	if (ret)
+		return ret;
+
+	ret = max96714_parse_dt(priv);
+	if (ret)
+		goto err_disable_core_hw;
+
+	max96714_init_tx_port(priv);
+
+	ret = max96714_rxport_enable_poc(priv);
+	if (ret)
+		goto err_free_ports;
+
+	ret = max96714_i2c_mux_init(priv);
+	if (ret)
+		goto err_disable_poc;
+
+	ret = max96714_create_subdev(priv);
+	if (ret)
+		goto err_del_mux;
+
+	return 0;
+
+err_del_mux:
+	i2c_mux_del_adapters(priv->mux);
+err_disable_poc:
+	max96714_rxport_disable_poc(priv);
+err_free_ports:
+	fwnode_handle_put(priv->rxport.source.ep_fwnode);
+err_disable_core_hw:
+	max96714_disable_core_hw(priv);
+
+	return ret;
+}
+
+static void max96714_remove(struct i2c_client *client)
+{
+	struct v4l2_subdev *sd = i2c_get_clientdata(client);
+	struct max96714_priv *priv = sd_to_max96714(sd);
+
+	max96714_destroy_subdev(priv);
+	i2c_mux_del_adapters(priv->mux);
+	max96714_rxport_disable_poc(priv);
+	fwnode_handle_put(priv->rxport.source.ep_fwnode);
+	max96714_disable_core_hw(priv);
+	gpiod_set_value_cansleep(priv->pd_gpio, 1);
+}
+
+static const struct of_device_id max96714_of_ids[] = {
+	{ .compatible = "maxim,max96714" },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, max96714_of_ids);
+
+static struct i2c_driver max96714_i2c_driver = {
+	.driver	= {
+		.name		= "max96714",
+		.of_match_table	= max96714_of_ids,
+	},
+	.probe		= max96714_probe,
+	.remove		= max96714_remove,
+};
+
+module_i2c_driver(max96714_i2c_driver);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Maxim Integrated GMSL2 Deserializers Driver");
+MODULE_AUTHOR("Julien Massot <julien.massot@collabora.com>");
-- 
2.44.0