[v3] media: i2c: add lt6911uxe hdmi bridge driver

Lontium LT9611UXE is a HDMI to MIPI CSI-2 bridge,
It supports modes up to 4k60fps, switches current mode when
plugging HDMI or changing the source active signal mode.

Signed-off-by: Dongcheng Yan <dongcheng.yan@intel.com>
---
v1 -> v2: replaced mutex with state_lock
v2 -> v3: fixed some pm_runtime err handlings

---
 drivers/media/i2c/Kconfig     |  12 +
 drivers/media/i2c/Makefile    |   1 +
 drivers/media/i2c/lt6911uxe.c | 627 ++++++++++++++++++++++++++++++++++
 3 files changed, 640 insertions(+)
 create mode 100644 drivers/media/i2c/lt6911uxe.c


base-commit: 2f87d0916ce0d2925cedbc9e8f5d6291ba2ac7b2

Hi Dongcheng,

Since this is an HDMI receiver, you need to implement the DV Timings API.

drivers/media/i2c/tc358743.c is a good example of this.

The LINK_FREQ/PIXEL_RATE controls do not apply to HDMI receivers, instead
the dv timings pad ops must be used.

I'm also missing EDID support.

So this needs quite a bit more work, I'm afraid.

How are you testing this device? Connected to a Raspberry Pi or something like that?

Regards,

	Hans

On 17/10/2024 05:08, Dongcheng Yan wrote:
> Lontium LT9611UXE is a HDMI to MIPI CSI-2 bridge,
> It supports modes up to 4k60fps, switches current mode when
> plugging HDMI or changing the source active signal mode.
> 
> Signed-off-by: Dongcheng Yan <dongcheng.yan@intel.com>
> ---
> v1 -> v2: replaced mutex with state_lock
> v2 -> v3: fixed some pm_runtime err handlings
> 
> ---
>  drivers/media/i2c/Kconfig     |  12 +
>  drivers/media/i2c/Makefile    |   1 +
>  drivers/media/i2c/lt6911uxe.c | 627 ++++++++++++++++++++++++++++++++++
>  3 files changed, 640 insertions(+)
>  create mode 100644 drivers/media/i2c/lt6911uxe.c
> 
> diff --git a/drivers/media/i2c/Kconfig b/drivers/media/i2c/Kconfig
> index 8ba096b8ebca..fbe3d0fe4ce6 100644
> --- a/drivers/media/i2c/Kconfig
> +++ b/drivers/media/i2c/Kconfig
> @@ -1526,6 +1526,18 @@ config VIDEO_I2C
>  	  To compile this driver as a module, choose M here: the
>  	  module will be called video-i2c
>  
> +config VIDEO_LT6911UXE
> +        tristate "Lontium LT6911UXE decoder"
> +        depends on ACPI && VIDEO_DEV
> +        select V4L2_FWNODE
> +        select V4L2_CCI_I2C
> +        help
> +          This is a Video4Linux2 sensor-level driver for the Lontium
> +          LT6911UXE HDMI to MIPI CSI-2 bridge.
> +
> +          To compile this driver as a module, choose M here: the
> +          module will be called lt6911uxe.
> +
>  config VIDEO_M52790
>  	tristate "Mitsubishi M52790 A/V switch"
>  	depends on VIDEO_DEV && I2C
> diff --git a/drivers/media/i2c/Makefile b/drivers/media/i2c/Makefile
> index fbb988bd067a..6c23a4463527 100644
> --- a/drivers/media/i2c/Makefile
> +++ b/drivers/media/i2c/Makefile
> @@ -64,6 +64,7 @@ obj-$(CONFIG_VIDEO_ISL7998X) += isl7998x.o
>  obj-$(CONFIG_VIDEO_KS0127) += ks0127.o
>  obj-$(CONFIG_VIDEO_LM3560) += lm3560.o
>  obj-$(CONFIG_VIDEO_LM3646) += lm3646.o
> +obj-$(CONFIG_VIDEO_LT6911UXE) += lt6911uxe.o
>  obj-$(CONFIG_VIDEO_M52790) += m52790.o
>  obj-$(CONFIG_VIDEO_MAX9271_LIB) += max9271.o
>  obj-$(CONFIG_VIDEO_MAX9286) += max9286.o
> diff --git a/drivers/media/i2c/lt6911uxe.c b/drivers/media/i2c/lt6911uxe.c
> new file mode 100644
> index 000000000000..61115b2bb92f
> --- /dev/null
> +++ b/drivers/media/i2c/lt6911uxe.c
> @@ -0,0 +1,627 @@
> +// SPDX-License-Identifier: GPL-2.0
> +// Copyright (c) 2023 - 2024 Intel Corporation.
> +
> +#include <linux/acpi.h>
> +#include <linux/delay.h>
> +#include <linux/gpio/consumer.h>
> +#include <linux/i2c.h>
> +#include <linux/interrupt.h>
> +#include <linux/module.h>
> +#include <linux/pm_runtime.h>
> +#include <linux/regmap.h>
> +#include <media/v4l2-cci.h>
> +#include <media/v4l2-ctrls.h>
> +#include <media/v4l2-device.h>
> +#include <media/v4l2-event.h>
> +#include <media/v4l2-fwnode.h>
> +
> +#define LT6911UXE_CHIP_ID		0x2102
> +#define REG_CHIP_ID			CCI_REG16(0xe100)
> +
> +#define REG_ENABLE_I2C			CCI_REG8(0xe0ee)
> +#define REG_PIX_CLK			CCI_REG24(0xe085)
> +#define REG_BYTE_CLK			CCI_REG24(0xe092)
> +#define REG_H_TOTAL			CCI_REG16(0xe088)
> +#define REG_V_TOTAL			CCI_REG16(0xe08a)
> +#define REG_HALF_H_ACTIVE		CCI_REG16(0xe08c)
> +#define REG_V_ACTIVE			CCI_REG16(0xe08e)
> +#define REG_MIPI_FORMAT			CCI_REG8(0xe096)
> +#define REG_MIPI_TX_CTRL		CCI_REG8(0xe0b0)
> +
> +/* Interrupts */
> +#define REG_INT_HDMI			CCI_REG8(0xe084)
> +#define INT_VIDEO_DISAPPEAR		0x0
> +#define INT_VIDEO_READY			0x1
> +
> +#define LT6911UXE_DEFAULT_WIDTH		3840
> +#define LT6911UXE_DEFAULT_HEIGHT	2160
> +#define LT6911UXE_DEFAULT_LANES		4
> +#define LT6911UXE_DEFAULT_FPS		30
> +#define LT6911UXE_MAX_LINK_FREQ		297000000
> +#define LT9611_PAGE_CONTROL		0xff
> +#define YUV422_8_BIT			0x7
> +
> +static const struct regmap_range_cfg lt9611uxe_ranges[] = {
> +	{
> +		.name = "register_range",
> +		.range_min =  0,
> +		.range_max = 0xffff,
> +		.selector_reg = LT9611_PAGE_CONTROL,
> +		.selector_mask = 0xff,
> +		.selector_shift = 0,
> +		.window_start = 0,
> +		.window_len = 0x100,
> +	},
> +};
> +
> +static const struct regmap_config lt9611uxe_regmap_config = {
> +	.reg_bits = 8,
> +	.val_bits = 8,
> +	.max_register = 0xffff,
> +	.ranges = lt9611uxe_ranges,
> +	.num_ranges = ARRAY_SIZE(lt9611uxe_ranges),
> +};
> +
> +struct lt6911uxe_mode {
> +	u32 width;
> +	u32 height;
> +	u32 code;
> +	u32 fps;
> +	u32 lanes;
> +	s64 link_freq;
> +};
> +
> +struct lt6911uxe {
> +	struct v4l2_subdev sd;
> +	struct media_pad pad;
> +	struct v4l2_ctrl_handler ctrl_handler;
> +	struct v4l2_ctrl *pixel_rate;
> +	struct v4l2_ctrl *link_freq;
> +
> +	struct lt6911uxe_mode cur_mode;
> +	struct regmap *regmap;
> +	struct gpio_desc *reset_gpio;
> +	struct gpio_desc *irq_gpio;
> +};
> +
> +static const struct v4l2_event lt6911uxe_ev_source_change = {
> +	.type = V4L2_EVENT_SOURCE_CHANGE,
> +	.u.src_change.changes = V4L2_EVENT_SRC_CH_RESOLUTION,
> +};
> +
> +static const struct v4l2_event lt6911uxe_ev_stream_end = {
> +	.type = V4L2_EVENT_EOS,
> +};
> +
> +static inline struct lt6911uxe *to_lt6911uxe(struct v4l2_subdev *sd)
> +{
> +	return container_of(sd, struct lt6911uxe, sd);
> +}
> +
> +static const struct lt6911uxe_mode default_mode = {
> +	.width = LT6911UXE_DEFAULT_WIDTH,
> +	.height = LT6911UXE_DEFAULT_HEIGHT,
> +	.code = MEDIA_BUS_FMT_UYVY8_1X16,
> +	.fps = LT6911UXE_DEFAULT_FPS,
> +	.lanes = LT6911UXE_DEFAULT_LANES,
> +	.link_freq = LT6911UXE_MAX_LINK_FREQ,
> +};
> +
> +static s64 get_pixel_rate(struct lt6911uxe *lt6911uxe)
> +{
> +	s64 pixel_rate;
> +
> +	pixel_rate = (s64)lt6911uxe->cur_mode.width *
> +		     lt6911uxe->cur_mode.height *
> +		     lt6911uxe->cur_mode.fps * 16;
> +	do_div(pixel_rate, lt6911uxe->cur_mode.lanes);
> +
> +	return pixel_rate;
> +}
> +
> +static int lt6911uxe_status_update(struct lt6911uxe *lt6911uxe)
> +{
> +	struct i2c_client *client = v4l2_get_subdevdata(&lt6911uxe->sd);
> +	u64 int_event;
> +	u64 byte_clk, pixel_clk, fps, format;
> +	u64 htotal, vtotal, half_width, height;
> +	int ret = 0;
> +
> +	/* Read interrupt event */
> +	cci_read(lt6911uxe->regmap, REG_INT_HDMI, &int_event, &ret);
> +	if (ret)
> +		return dev_err_probe(&client->dev, ret,
> +				     "failed to read interrupt event\n");
> +
> +	switch (int_event) {
> +	case INT_VIDEO_READY:
> +		cci_read(lt6911uxe->regmap, REG_BYTE_CLK, &byte_clk, &ret);
> +		byte_clk *= 1000;
> +		cci_read(lt6911uxe->regmap, REG_PIX_CLK, &pixel_clk, &ret);
> +		pixel_clk *= 1000;
> +
> +		if (ret || byte_clk == 0 || pixel_clk == 0) {
> +			dev_err(&client->dev,
> +				"invalid ByteClock or PixelClock\n");
> +			return -EINVAL;
> +		}
> +
> +		cci_read(lt6911uxe->regmap, REG_H_TOTAL, &htotal, &ret);
> +		cci_read(lt6911uxe->regmap, REG_V_TOTAL, &vtotal, &ret);
> +		if (ret || htotal == 0 || vtotal == 0) {
> +			dev_err(&client->dev, "invalid htotal or vtotal\n");
> +			return -EINVAL;
> +		}
> +
> +		fps = div_u64(pixel_clk, htotal * vtotal);
> +		if (fps > 60) {
> +			dev_err(&client->dev,
> +				"max fps is 60, current fps: %llu\n", fps);
> +			return -EINVAL;
> +		}
> +
> +		cci_read(lt6911uxe->regmap, REG_HALF_H_ACTIVE,
> +			 &half_width, &ret);
> +		cci_read(lt6911uxe->regmap, REG_V_ACTIVE, &height, &ret);
> +		if (ret || half_width == 0 || half_width * 2 > 3840 ||
> +		    height == 0 || height > 2160) {
> +			dev_err(&client->dev, "invalid width or height\n");
> +			return -EINVAL;
> +		}
> +
> +		/*
> +		 * Get MIPI format, YUV422_8_BIT is expected in lt6911uxe
> +		 */
> +		cci_read(lt6911uxe->regmap, REG_MIPI_FORMAT, &format, &ret);
> +		if (format != YUV422_8_BIT) {
> +			dev_err(&client->dev, "invalid MIPI format\n");
> +			return -EINVAL;
> +		}
> +
> +		lt6911uxe->cur_mode.height = height;
> +		lt6911uxe->cur_mode.width = half_width * 2;
> +		lt6911uxe->cur_mode.fps = fps;
> +		/* MIPI Clock Rate = ByteClock × 4, defined in lt6911uxe spec */
> +		lt6911uxe->cur_mode.link_freq = byte_clk * 4;
> +		v4l2_subdev_notify_event(&lt6911uxe->sd,
> +					 &lt6911uxe_ev_source_change);
> +		break;
> +
> +	case INT_VIDEO_DISAPPEAR:
> +		cci_write(lt6911uxe->regmap, REG_MIPI_TX_CTRL, 0x0, NULL);
> +		lt6911uxe->cur_mode.height = 0;
> +		lt6911uxe->cur_mode.width = 0;
> +		lt6911uxe->cur_mode.fps = 0;
> +		lt6911uxe->cur_mode.link_freq = 0;
> +		v4l2_subdev_notify_event(&lt6911uxe->sd,
> +					 &lt6911uxe_ev_stream_end);
> +		break;
> +
> +	default:
> +		return  -ENOLINK;
> +	}
> +
> +	return ret;
> +}
> +
> +static int lt6911uxe_init_controls(struct lt6911uxe *lt6911uxe)
> +{
> +	struct v4l2_ctrl_handler *ctrl_hdlr;
> +	s64 pixel_rate;
> +	int ret;
> +
> +	ctrl_hdlr = &lt6911uxe->ctrl_handler;
> +	ret = v4l2_ctrl_handler_init(ctrl_hdlr, 8);
> +	if (ret)
> +		return ret;
> +
> +	lt6911uxe->link_freq = v4l2_ctrl_new_std(ctrl_hdlr, NULL,
> +						 V4L2_CID_CUR_LINK_FREQ, 0,
> +						 LT6911UXE_MAX_LINK_FREQ, 1,
> +						 lt6911uxe->cur_mode.link_freq);
> +
> +	pixel_rate = get_pixel_rate(lt6911uxe);
> +	lt6911uxe->pixel_rate = v4l2_ctrl_new_std(ctrl_hdlr, NULL,
> +						  V4L2_CID_PIXEL_RATE,
> +						  pixel_rate, pixel_rate, 1,
> +						  pixel_rate);
> +
> +	if (ctrl_hdlr->error) {
> +		ret = ctrl_hdlr->error;
> +		goto hdlr_free;
> +	}
> +	lt6911uxe->sd.ctrl_handler = ctrl_hdlr;
> +
> +	return 0;
> +
> +hdlr_free:
> +	v4l2_ctrl_handler_free(ctrl_hdlr);
> +	return ret;
> +}
> +
> +static void lt6911uxe_update_pad_format(const struct lt6911uxe_mode *mode,
> +					struct v4l2_mbus_framefmt *fmt)
> +{
> +	fmt->width = mode->width;
> +	fmt->height = mode->height;
> +	fmt->code = mode->code;
> +	fmt->field = V4L2_FIELD_NONE;
> +}
> +
> +static int lt6911uxe_enable_streams(struct v4l2_subdev *sd,
> +				    struct v4l2_subdev_state *state,
> +				    u32 pad, u64 streams_mask)
> +{
> +	struct i2c_client *client = v4l2_get_subdevdata(sd);
> +	struct lt6911uxe *lt6911uxe = to_lt6911uxe(sd);
> +	int ret;
> +
> +	ret = pm_runtime_resume_and_get(&client->dev);
> +	if (ret < 0)
> +		return ret;
> +
> +	cci_write(lt6911uxe->regmap, REG_MIPI_TX_CTRL, 0x1, &ret);
> +	if (ret) {
> +		dev_err(&client->dev, "failed to start stream: %d\n", ret);
> +		goto err_rpm_put;
> +	}
> +
> +	return 0;
> +
> +err_rpm_put:
> +	pm_runtime_put(&client->dev);
> +	return ret;
> +}
> +
> +static int lt6911uxe_disable_streams(struct v4l2_subdev *sd,
> +				     struct v4l2_subdev_state *state,
> +				     u32 pad, u64 streams_mask)
> +{
> +	struct lt6911uxe *lt6911uxe = to_lt6911uxe(sd);
> +	struct i2c_client *client = v4l2_get_subdevdata(&lt6911uxe->sd);
> +	int ret;
> +
> +	ret = cci_write(lt6911uxe->regmap, REG_MIPI_TX_CTRL, 0x0, NULL);
> +	if (ret)
> +		dev_err(&client->dev, "failed to stop stream: %d\n", ret);
> +
> +	pm_runtime_put(&client->dev);
> +	return 0;
> +}
> +
> +static int lt6911uxe_set_format(struct v4l2_subdev *sd,
> +				struct v4l2_subdev_state *sd_state,
> +				struct v4l2_subdev_format *fmt)
> +{
> +	struct lt6911uxe *lt6911uxe = to_lt6911uxe(sd);
> +	u64 pixel_rate, link_freq;
> +
> +	lt6911uxe_update_pad_format(&lt6911uxe->cur_mode, &fmt->format);
> +	*v4l2_subdev_state_get_format(sd_state, fmt->pad) = fmt->format;
> +	if (fmt->which == V4L2_SUBDEV_FORMAT_TRY)
> +		return 0;
> +
> +	pixel_rate = get_pixel_rate(lt6911uxe);
> +	__v4l2_ctrl_modify_range(lt6911uxe->pixel_rate, pixel_rate,
> +				 pixel_rate, 1, pixel_rate);
> +
> +	link_freq = lt6911uxe->cur_mode.link_freq;
> +	__v4l2_ctrl_modify_range(lt6911uxe->link_freq, link_freq,
> +				 link_freq, 1, link_freq);
> +
> +	return 0;
> +}
> +
> +static int lt6911uxe_enum_mbus_code(struct v4l2_subdev *sd,
> +				    struct v4l2_subdev_state *sd_state,
> +				    struct v4l2_subdev_mbus_code_enum *code)
> +{
> +	struct lt6911uxe *lt6911uxe = to_lt6911uxe(sd);
> +
> +	if (code->index)
> +		return -EINVAL;
> +
> +	code->code = lt6911uxe->cur_mode.code;
> +
> +	return 0;
> +}
> +
> +static int lt6911uxe_enum_frame_size(struct v4l2_subdev *sd,
> +				     struct v4l2_subdev_state *sd_state,
> +				     struct v4l2_subdev_frame_size_enum *fse)
> +{
> +	struct lt6911uxe *lt6911uxe = to_lt6911uxe(sd);
> +
> +	if (fse->index != 0)
> +		return -EINVAL;
> +
> +	if (fse->code != MEDIA_BUS_FMT_UYVY8_1X16)
> +		return -EINVAL;
> +
> +	fse->min_width = lt6911uxe->cur_mode.width;
> +	fse->max_width = fse->min_width;
> +	fse->min_height = lt6911uxe->cur_mode.height;
> +	fse->max_height = fse->min_height;
> +
> +	return 0;
> +}
> +
> +static int lt6911uxe_enum_frame_interval(struct v4l2_subdev *sd,
> +		struct v4l2_subdev_state *sd_state,
> +		struct v4l2_subdev_frame_interval_enum *fie)
> +{
> +	struct lt6911uxe *lt6911uxe = to_lt6911uxe(sd);
> +
> +	if (fie->index != 0)
> +		return -EINVAL;
> +
> +	fie->interval.numerator = 1;
> +	fie->interval.denominator = lt6911uxe->cur_mode.fps;
> +
> +	return 0;
> +}
> +
> +static int lt6911uxe_init_state(struct v4l2_subdev *sd,
> +				struct v4l2_subdev_state *sd_state)
> +{
> +	struct v4l2_subdev_format fmt = {
> +		.which = V4L2_SUBDEV_FORMAT_TRY,
> +		.pad = 0,
> +		.format = {
> +			.code = MEDIA_BUS_FMT_UYVY8_1X16,
> +			.width = LT6911UXE_DEFAULT_WIDTH,
> +			.height = LT6911UXE_DEFAULT_HEIGHT,
> +		},
> +	};
> +
> +	return lt6911uxe_set_format(sd, sd_state, &fmt);
> +}
> +
> +static const struct v4l2_subdev_video_ops lt6911uxe_video_ops = {
> +	.s_stream = v4l2_subdev_s_stream_helper,
> +};
> +
> +static const struct v4l2_subdev_pad_ops lt6911uxe_pad_ops = {
> +	.set_fmt = lt6911uxe_set_format,
> +	.get_fmt = v4l2_subdev_get_fmt,
> +	.enable_streams = lt6911uxe_enable_streams,
> +	.disable_streams = lt6911uxe_disable_streams,
> +	.enum_mbus_code = lt6911uxe_enum_mbus_code,
> +	.enum_frame_size = lt6911uxe_enum_frame_size,
> +	.enum_frame_interval = lt6911uxe_enum_frame_interval,
> +};
> +
> +static const struct v4l2_subdev_core_ops lt6911uxe_subdev_core_ops = {
> +	.subscribe_event = v4l2_ctrl_subdev_subscribe_event,
> +	.unsubscribe_event = v4l2_event_subdev_unsubscribe,
> +};
> +
> +static const struct v4l2_subdev_ops lt6911uxe_subdev_ops = {
> +	.core = &lt6911uxe_subdev_core_ops,
> +	.video = &lt6911uxe_video_ops,
> +	.pad = &lt6911uxe_pad_ops,
> +};
> +
> +static const struct media_entity_operations lt6911uxe_subdev_entity_ops = {
> +	.link_validate = v4l2_subdev_link_validate,
> +};
> +
> +static const struct v4l2_subdev_internal_ops lt6911uxe_internal_ops = {
> +	.init_state = lt6911uxe_init_state,
> +};
> +
> +static int lt6911uxe_fwnode_parse(struct lt6911uxe *lt6911uxe,
> +				  struct device *dev)
> +{
> +	struct fwnode_handle *endpoint;
> +	struct v4l2_fwnode_endpoint bus_cfg = {
> +		.bus_type = V4L2_MBUS_CSI2_DPHY,
> +	};
> +	int ret;
> +
> +	endpoint = fwnode_graph_get_endpoint_by_id(dev_fwnode(dev), 0, 0,
> +						   FWNODE_GRAPH_ENDPOINT_NEXT);
> +	if (!endpoint)
> +		return dev_err_probe(dev, -EPROBE_DEFER,
> +				     "endpoint node not found\n");
> +
> +	ret = v4l2_fwnode_endpoint_parse(endpoint, &bus_cfg);
> +	fwnode_handle_put(endpoint);
> +	if (ret) {
> +		dev_err(dev, "failed to parse endpoint node: %d\n", ret);
> +		goto out_err;
> +	}
> +
> +	/*
> +	 * Check the number of MIPI CSI2 data lanes,
> +	 * lt6911uxe only support 4 lanes.
> +	 */
> +	if (bus_cfg.bus.mipi_csi2.num_data_lanes != LT6911UXE_DEFAULT_LANES) {
> +		dev_err(dev, "only 4 data lanes are currently supported\n");
> +		goto out_err;
> +	}
> +
> +	return 0;
> +
> +out_err:
> +	v4l2_fwnode_endpoint_free(&bus_cfg);
> +	return ret;
> +}
> +
> +static int lt6911uxe_identify_module(struct lt6911uxe *lt6911uxe,
> +				     struct device *dev)
> +{
> +	u64 val;
> +	int ret = 0;
> +
> +	/* Chip ID should be confirmed when the I2C slave is active */
> +	cci_write(lt6911uxe->regmap, REG_ENABLE_I2C, 0x1, &ret);
> +	cci_read(lt6911uxe->regmap, REG_CHIP_ID, &val, &ret);
> +	cci_write(lt6911uxe->regmap, REG_ENABLE_I2C, 0x0, &ret);
> +	if (ret)
> +		return dev_err_probe(dev, ret, "fail to read chip id\n");
> +
> +	if (val != LT6911UXE_CHIP_ID) {
> +		return dev_err_probe(dev, -ENXIO, "chip id mismatch: %x!=%x\n",
> +				     LT6911UXE_CHIP_ID, (u16)val);
> +	}
> +
> +	return 0;
> +}
> +
> +static irqreturn_t lt6911uxe_threaded_irq_fn(int irq, void *dev_id)
> +{
> +	struct v4l2_subdev *sd = dev_id;
> +	struct lt6911uxe *lt6911uxe = to_lt6911uxe(sd);
> +	struct v4l2_subdev_state *state;
> +
> +	state = v4l2_subdev_lock_and_get_active_state(sd);
> +	lt6911uxe_status_update(lt6911uxe);
> +	v4l2_subdev_unlock_state(state);
> +
> +	return IRQ_HANDLED;
> +}
> +
> +static void lt6911uxe_remove(struct i2c_client *client)
> +{
> +	struct v4l2_subdev *sd = i2c_get_clientdata(client);
> +	struct lt6911uxe *lt6911uxe = to_lt6911uxe(sd);
> +
> +	free_irq(gpiod_to_irq(lt6911uxe->irq_gpio), lt6911uxe);
> +	v4l2_async_unregister_subdev(sd);
> +	v4l2_subdev_cleanup(sd);
> +	media_entity_cleanup(&sd->entity);
> +	v4l2_ctrl_handler_free(&lt6911uxe->ctrl_handler);
> +	pm_runtime_disable(&client->dev);
> +	pm_runtime_set_suspended(&client->dev);
> +}
> +
> +static int lt6911uxe_probe(struct i2c_client *client)
> +{
> +	struct lt6911uxe *lt6911uxe;
> +	struct device *dev = &client->dev;
> +	u64 irq_pin_flags;
> +	int ret;
> +
> +	lt6911uxe = devm_kzalloc(dev, sizeof(*lt6911uxe), GFP_KERNEL);
> +	if (!lt6911uxe)
> +		return -ENOMEM;
> +
> +	/* define default mode: 4k@60fps, changed when interrupt occurs. */
> +	lt6911uxe->cur_mode = default_mode;
> +
> +	lt6911uxe->regmap = devm_regmap_init_i2c(client,
> +						 &lt9611uxe_regmap_config);
> +	if (IS_ERR(lt6911uxe->regmap))
> +		return dev_err_probe(dev, PTR_ERR(lt6911uxe->regmap),
> +				     "failed to init CCI\n");
> +
> +	v4l2_i2c_subdev_init(&lt6911uxe->sd, client, &lt6911uxe_subdev_ops);
> +
> +	lt6911uxe->reset_gpio = devm_gpiod_get(dev, "reset", GPIOD_IN);
> +	if (IS_ERR(lt6911uxe->reset_gpio))
> +		return dev_err_probe(dev, PTR_ERR(lt6911uxe->reset_gpio),
> +				     "failed to get reset gpio\n");
> +
> +	lt6911uxe->irq_gpio = devm_gpiod_get(dev, "readystat", GPIOD_IN);
> +	if (IS_ERR(lt6911uxe->irq_gpio))
> +		return dev_err_probe(dev, PTR_ERR(lt6911uxe->irq_gpio),
> +				     "failed to get ready_stat gpio\n");
> +
> +	ret = lt6911uxe_fwnode_parse(lt6911uxe, dev);
> +	if (ret)
> +		return ret;
> +
> +	usleep_range(10000, 10500);
> +
> +	ret = lt6911uxe_identify_module(lt6911uxe, dev);
> +	if (ret)
> +		return dev_err_probe(dev, ret, "failed to find chip\n");
> +
> +	ret = lt6911uxe_init_controls(lt6911uxe);
> +	if (ret)
> +		return dev_err_probe(dev, ret, "failed to init control\n");
> +
> +	lt6911uxe->sd.dev = dev;
> +	lt6911uxe->sd.internal_ops = &lt6911uxe_internal_ops;
> +	lt6911uxe->sd.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE |
> +			       V4L2_SUBDEV_FL_HAS_EVENTS;
> +	lt6911uxe->sd.entity.ops = &lt6911uxe_subdev_entity_ops;
> +	lt6911uxe->sd.entity.function = MEDIA_ENT_F_VID_IF_BRIDGE;
> +	lt6911uxe->pad.flags = MEDIA_PAD_FL_SOURCE;
> +	ret = media_entity_pads_init(&lt6911uxe->sd.entity, 1, &lt6911uxe->pad);
> +	if (ret) {
> +		dev_err(dev, "failed to init entity pads: %d\n", ret);
> +		goto v4l2_ctrl_handler_free;
> +	}
> +
> +	/*
> +	 * Device is already turned on by i2c-core with ACPI domain PM.
> +	 * Enable runtime PM and turn off the device.
> +	 */
> +	pm_runtime_set_active(dev);
> +	pm_runtime_enable(dev);
> +	pm_runtime_idle(dev);
> +
> +	ret = v4l2_subdev_init_finalize(&lt6911uxe->sd);
> +	if (ret) {
> +		dev_err(dev, "failed to init v4l2 subdev: %d\n", ret);
> +		goto media_entity_cleanup;
> +	}
> +
> +	/* Setting irq */
> +	irq_pin_flags = IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING |
> +			IRQF_ONESHOT;
> +
> +	ret = request_threaded_irq(gpiod_to_irq(lt6911uxe->irq_gpio), NULL,
> +				   lt6911uxe_threaded_irq_fn,
> +				   irq_pin_flags, NULL, lt6911uxe);
> +	if (ret) {
> +		dev_err(dev, "failed to request IRQ: %d\n", ret);
> +		goto subdev_cleanup;
> +	}
> +
> +	ret = v4l2_async_register_subdev_sensor(&lt6911uxe->sd);
> +	if (ret) {
> +		dev_err(dev, "failed to register V4L2 subdev: %d\n", ret);
> +		goto free_irq;
> +	}
> +
> +	return 0;
> +
> +free_irq:
> +	free_irq(gpiod_to_irq(lt6911uxe->irq_gpio), lt6911uxe);
> +
> +subdev_cleanup:
> +	v4l2_subdev_cleanup(&lt6911uxe->sd);
> +
> +media_entity_cleanup:
> +	pm_runtime_disable(dev);
> +	pm_runtime_set_suspended(dev);
> +	media_entity_cleanup(&lt6911uxe->sd.entity);
> +
> +v4l2_ctrl_handler_free:
> +	v4l2_ctrl_handler_free(lt6911uxe->sd.ctrl_handler);
> +	return ret;
> +}
> +
> +static const struct acpi_device_id lt6911uxe_acpi_ids[] = {
> +	{ "INTC10C5" },
> +	{}
> +};
> +MODULE_DEVICE_TABLE(acpi, lt6911uxe_acpi_ids);
> +
> +static struct i2c_driver lt6911uxe_i2c_driver = {
> +	.driver = {
> +		.name = "lt6911uxe",
> +		.acpi_match_table = ACPI_PTR(lt6911uxe_acpi_ids),
> +	},
> +	.probe = lt6911uxe_probe,
> +	.remove = lt6911uxe_remove,
> +};
> +
> +module_i2c_driver(lt6911uxe_i2c_driver);
> +
> +MODULE_AUTHOR("Yan Dongcheng <dongcheng.yan@intel.com>");
> +MODULE_DESCRIPTION("Lontium lt6911uxe HDMI to MIPI Bridge Driver");
> +MODULE_LICENSE("GPL");
> 
> base-commit: 2f87d0916ce0d2925cedbc9e8f5d6291ba2ac7b2

Hi Hans,

On Wed, Oct 23, 2024 at 02:28:02PM +0200, Hans Verkuil wrote:
> Hi Dongcheng,
> 
> Since this is an HDMI receiver, you need to implement the DV Timings API.

"Must"? Why?

I don't know the tc358743 driver but it'd unlikely to work with current
CSI-2 RX drivers. They expect the LINK_FREQ control for instance, not the
DV timing API.
<URL:https://hverkuil.home.xs4all.nl/spec/driver-api/tx-rx.html#transmitter-receiver>

On 25/10/2024 06:06, Yan, Dongcheng wrote:
> Hi Hans,
> 
> On 10/23/2024 8:28 PM, Hans Verkuil wrote:
>> Hi Dongcheng,
>>
>> Since this is an HDMI receiver, you need to implement the DV Timings API.
>>
>> drivers/media/i2c/tc358743.c is a good example of this.
>>
>> The LINK_FREQ/PIXEL_RATE controls do not apply to HDMI receivers, instead
>> the dv timings pad ops must be used.
> 
> 
> This is a HDMI to CSI2 bridge, more like a CSI-2 receiver rather than an HDMI receiver.
> 
> I will implement DV timing API and refer to tc358743, thx for your suggestion.
> 
> But LINK_FREQ/PIXEL_RATE is still needed in MIPI config programing. Do you think so?

The other HDMI to CSI bridges do not need this, take a look how the  tc358743
driver handles it.

> 
>> I'm also missing EDID support.
> 
> 
> Since it is a MIPI CSI-2 receiver, I don't know EDID before, I think you may have
> 
> misunderstood LT6911UXE, it does not need this support in my sight.

Yes, it does. I think it comes with a default EDID, but you want to be able to change
it. Often the EDID capabilities are not only defined by the capabilities of the
receiver, but also by the capabilities of the device as a whole. E.g., does the
video pipeline support interlaced formats or not?

So for a proper driver you need to support it. I worked with this bridge myself and
I know there is documentation on how to read/write the EDID.

Regards,

	Hans

> 
> 
>> So this needs quite a bit more work, I'm afraid.
>>
>> How are you testing this device? Connected to a Raspberry Pi or something like that?
> 
> 
> Yes, I used it in my poject based on IPU6 which is an ISP engine, this driver has been applied in many products.
> 
> IPU6 driver is also upstreamed and you can find it in "/drivers/media/pci/intel/ipu6/".
> 
> 
> Thanks,
> 
> Dongcheng
> 
>> Regards,
>>
>> 	Hans
>>
>> On 17/10/2024 05:08, Dongcheng Yan wrote:
>>> Lontium LT9611UXE is a HDMI to MIPI CSI-2 bridge,
>>> It supports modes up to 4k60fps, switches current mode when
>>> plugging HDMI or changing the source active signal mode.
>>>
>>> Signed-off-by: Dongcheng Yan <dongcheng.yan@intel.com>
>>> ---
>>> v1 -> v2: replaced mutex with state_lock
>>> v2 -> v3: fixed some pm_runtime err handlings
>>>
>>> ---
>>>  drivers/media/i2c/Kconfig     |  12 +
>>>  drivers/media/i2c/Makefile    |   1 +
>>>  drivers/media/i2c/lt6911uxe.c | 627 ++++++++++++++++++++++++++++++++++
>>>  3 files changed, 640 insertions(+)
>>>  create mode 100644 drivers/media/i2c/lt6911uxe.c
>>>
>>> diff --git a/drivers/media/i2c/Kconfig b/drivers/media/i2c/Kconfig
>>> index 8ba096b8ebca..fbe3d0fe4ce6 100644
>>> --- a/drivers/media/i2c/Kconfig
>>> +++ b/drivers/media/i2c/Kconfig
>>> @@ -1526,6 +1526,18 @@ config VIDEO_I2C
>>>  	  To compile this driver as a module, choose M here: the
>>>  	  module will be called video-i2c
>>>  
>>> +config VIDEO_LT6911UXE
>>> +        tristate "Lontium LT6911UXE decoder"
>>> +        depends on ACPI && VIDEO_DEV
>>> +        select V4L2_FWNODE
>>> +        select V4L2_CCI_I2C
>>> +        help
>>> +          This is a Video4Linux2 sensor-level driver for the Lontium
>>> +          LT6911UXE HDMI to MIPI CSI-2 bridge.
>>> +
>>> +          To compile this driver as a module, choose M here: the
>>> +          module will be called lt6911uxe.
>>> +
>>>  config VIDEO_M52790
>>>  	tristate "Mitsubishi M52790 A/V switch"
>>>  	depends on VIDEO_DEV && I2C
>>> diff --git a/drivers/media/i2c/Makefile b/drivers/media/i2c/Makefile
>>> index fbb988bd067a..6c23a4463527 100644
>>> --- a/drivers/media/i2c/Makefile
>>> +++ b/drivers/media/i2c/Makefile
>>> @@ -64,6 +64,7 @@ obj-$(CONFIG_VIDEO_ISL7998X) += isl7998x.o
>>>  obj-$(CONFIG_VIDEO_KS0127) += ks0127.o
>>>  obj-$(CONFIG_VIDEO_LM3560) += lm3560.o
>>>  obj-$(CONFIG_VIDEO_LM3646) += lm3646.o
>>> +obj-$(CONFIG_VIDEO_LT6911UXE) += lt6911uxe.o
>>>  obj-$(CONFIG_VIDEO_M52790) += m52790.o
>>>  obj-$(CONFIG_VIDEO_MAX9271_LIB) += max9271.o
>>>  obj-$(CONFIG_VIDEO_MAX9286) += max9286.o
>>> diff --git a/drivers/media/i2c/lt6911uxe.c b/drivers/media/i2c/lt6911uxe.c
>>> new file mode 100644
>>> index 000000000000..61115b2bb92f
>>> --- /dev/null
>>> +++ b/drivers/media/i2c/lt6911uxe.c
>>> @@ -0,0 +1,627 @@
>>> +// SPDX-License-Identifier: GPL-2.0
>>> +// Copyright (c) 2023 - 2024 Intel Corporation.
>>> +
>>> +#include <linux/acpi.h>
>>> +#include <linux/delay.h>
>>> +#include <linux/gpio/consumer.h>
>>> +#include <linux/i2c.h>
>>> +#include <linux/interrupt.h>
>>> +#include <linux/module.h>
>>> +#include <linux/pm_runtime.h>
>>> +#include <linux/regmap.h>
>>> +#include <media/v4l2-cci.h>
>>> +#include <media/v4l2-ctrls.h>
>>> +#include <media/v4l2-device.h>
>>> +#include <media/v4l2-event.h>
>>> +#include <media/v4l2-fwnode.h>
>>> +
>>> +#define LT6911UXE_CHIP_ID		0x2102
>>> +#define REG_CHIP_ID			CCI_REG16(0xe100)
>>> +
>>> +#define REG_ENABLE_I2C			CCI_REG8(0xe0ee)
>>> +#define REG_PIX_CLK			CCI_REG24(0xe085)
>>> +#define REG_BYTE_CLK			CCI_REG24(0xe092)
>>> +#define REG_H_TOTAL			CCI_REG16(0xe088)
>>> +#define REG_V_TOTAL			CCI_REG16(0xe08a)
>>> +#define REG_HALF_H_ACTIVE		CCI_REG16(0xe08c)
>>> +#define REG_V_ACTIVE			CCI_REG16(0xe08e)
>>> +#define REG_MIPI_FORMAT			CCI_REG8(0xe096)
>>> +#define REG_MIPI_TX_CTRL		CCI_REG8(0xe0b0)
>>> +
>>> +/* Interrupts */
>>> +#define REG_INT_HDMI			CCI_REG8(0xe084)
>>> +#define INT_VIDEO_DISAPPEAR		0x0
>>> +#define INT_VIDEO_READY			0x1
>>> +
>>> +#define LT6911UXE_DEFAULT_WIDTH		3840
>>> +#define LT6911UXE_DEFAULT_HEIGHT	2160
>>> +#define LT6911UXE_DEFAULT_LANES		4
>>> +#define LT6911UXE_DEFAULT_FPS		30
>>> +#define LT6911UXE_MAX_LINK_FREQ		297000000
>>> +#define LT9611_PAGE_CONTROL		0xff
>>> +#define YUV422_8_BIT			0x7
>>> +
>>> +static const struct regmap_range_cfg lt9611uxe_ranges[] = {
>>> +	{
>>> +		.name = "register_range",
>>> +		.range_min =  0,
>>> +		.range_max = 0xffff,
>>> +		.selector_reg = LT9611_PAGE_CONTROL,
>>> +		.selector_mask = 0xff,
>>> +		.selector_shift = 0,
>>> +		.window_start = 0,
>>> +		.window_len = 0x100,
>>> +	},
>>> +};
>>> +
>>> +static const struct regmap_config lt9611uxe_regmap_config = {
>>> +	.reg_bits = 8,
>>> +	.val_bits = 8,
>>> +	.max_register = 0xffff,
>>> +	.ranges = lt9611uxe_ranges,
>>> +	.num_ranges = ARRAY_SIZE(lt9611uxe_ranges),
>>> +};
>>> +
>>> +struct lt6911uxe_mode {
>>> +	u32 width;
>>> +	u32 height;
>>> +	u32 code;
>>> +	u32 fps;
>>> +	u32 lanes;
>>> +	s64 link_freq;
>>> +};
>>> +
>>> +struct lt6911uxe {
>>> +	struct v4l2_subdev sd;
>>> +	struct media_pad pad;
>>> +	struct v4l2_ctrl_handler ctrl_handler;
>>> +	struct v4l2_ctrl *pixel_rate;
>>> +	struct v4l2_ctrl *link_freq;
>>> +
>>> +	struct lt6911uxe_mode cur_mode;
>>> +	struct regmap *regmap;
>>> +	struct gpio_desc *reset_gpio;
>>> +	struct gpio_desc *irq_gpio;
>>> +};
>>> +
>>> +static const struct v4l2_event lt6911uxe_ev_source_change = {
>>> +	.type = V4L2_EVENT_SOURCE_CHANGE,
>>> +	.u.src_change.changes = V4L2_EVENT_SRC_CH_RESOLUTION,
>>> +};
>>> +
>>> +static const struct v4l2_event lt6911uxe_ev_stream_end = {
>>> +	.type = V4L2_EVENT_EOS,
>>> +};
>>> +
>>> +static inline struct lt6911uxe *to_lt6911uxe(struct v4l2_subdev *sd)
>>> +{
>>> +	return container_of(sd, struct lt6911uxe, sd);
>>> +}
>>> +
>>> +static const struct lt6911uxe_mode default_mode = {
>>> +	.width = LT6911UXE_DEFAULT_WIDTH,
>>> +	.height = LT6911UXE_DEFAULT_HEIGHT,
>>> +	.code = MEDIA_BUS_FMT_UYVY8_1X16,
>>> +	.fps = LT6911UXE_DEFAULT_FPS,
>>> +	.lanes = LT6911UXE_DEFAULT_LANES,
>>> +	.link_freq = LT6911UXE_MAX_LINK_FREQ,
>>> +};
>>> +
>>> +static s64 get_pixel_rate(struct lt6911uxe *lt6911uxe)
>>> +{
>>> +	s64 pixel_rate;
>>> +
>>> +	pixel_rate = (s64)lt6911uxe->cur_mode.width *
>>> +		     lt6911uxe->cur_mode.height *
>>> +		     lt6911uxe->cur_mode.fps * 16;
>>> +	do_div(pixel_rate, lt6911uxe->cur_mode.lanes);
>>> +
>>> +	return pixel_rate;
>>> +}
>>> +
>>> +static int lt6911uxe_status_update(struct lt6911uxe *lt6911uxe)
>>> +{
>>> +	struct i2c_client *client = v4l2_get_subdevdata(&lt6911uxe->sd);
>>> +	u64 int_event;
>>> +	u64 byte_clk, pixel_clk, fps, format;
>>> +	u64 htotal, vtotal, half_width, height;
>>> +	int ret = 0;
>>> +
>>> +	/* Read interrupt event */
>>> +	cci_read(lt6911uxe->regmap, REG_INT_HDMI, &int_event, &ret);
>>> +	if (ret)
>>> +		return dev_err_probe(&client->dev, ret,
>>> +				     "failed to read interrupt event\n");
>>> +
>>> +	switch (int_event) {
>>> +	case INT_VIDEO_READY:
>>> +		cci_read(lt6911uxe->regmap, REG_BYTE_CLK, &byte_clk, &ret);
>>> +		byte_clk *= 1000;
>>> +		cci_read(lt6911uxe->regmap, REG_PIX_CLK, &pixel_clk, &ret);
>>> +		pixel_clk *= 1000;
>>> +
>>> +		if (ret || byte_clk == 0 || pixel_clk == 0) {
>>> +			dev_err(&client->dev,
>>> +				"invalid ByteClock or PixelClock\n");
>>> +			return -EINVAL;
>>> +		}
>>> +
>>> +		cci_read(lt6911uxe->regmap, REG_H_TOTAL, &htotal, &ret);
>>> +		cci_read(lt6911uxe->regmap, REG_V_TOTAL, &vtotal, &ret);
>>> +		if (ret || htotal == 0 || vtotal == 0) {
>>> +			dev_err(&client->dev, "invalid htotal or vtotal\n");
>>> +			return -EINVAL;
>>> +		}
>>> +
>>> +		fps = div_u64(pixel_clk, htotal * vtotal);
>>> +		if (fps > 60) {
>>> +			dev_err(&client->dev,
>>> +				"max fps is 60, current fps: %llu\n", fps);
>>> +			return -EINVAL;
>>> +		}
>>> +
>>> +		cci_read(lt6911uxe->regmap, REG_HALF_H_ACTIVE,
>>> +			 &half_width, &ret);
>>> +		cci_read(lt6911uxe->regmap, REG_V_ACTIVE, &height, &ret);
>>> +		if (ret || half_width == 0 || half_width * 2 > 3840 ||
>>> +		    height == 0 || height > 2160) {
>>> +			dev_err(&client->dev, "invalid width or height\n");
>>> +			return -EINVAL;
>>> +		}
>>> +
>>> +		/*
>>> +		 * Get MIPI format, YUV422_8_BIT is expected in lt6911uxe
>>> +		 */
>>> +		cci_read(lt6911uxe->regmap, REG_MIPI_FORMAT, &format, &ret);
>>> +		if (format != YUV422_8_BIT) {
>>> +			dev_err(&client->dev, "invalid MIPI format\n");
>>> +			return -EINVAL;
>>> +		}
>>> +
>>> +		lt6911uxe->cur_mode.height = height;
>>> +		lt6911uxe->cur_mode.width = half_width * 2;
>>> +		lt6911uxe->cur_mode.fps = fps;
>>> +		/* MIPI Clock Rate = ByteClock × 4, defined in lt6911uxe spec */
>>> +		lt6911uxe->cur_mode.link_freq = byte_clk * 4;
>>> +		v4l2_subdev_notify_event(&lt6911uxe->sd,
>>> +					 &lt6911uxe_ev_source_change);
>>> +		break;
>>> +
>>> +	case INT_VIDEO_DISAPPEAR:
>>> +		cci_write(lt6911uxe->regmap, REG_MIPI_TX_CTRL, 0x0, NULL);
>>> +		lt6911uxe->cur_mode.height = 0;
>>> +		lt6911uxe->cur_mode.width = 0;
>>> +		lt6911uxe->cur_mode.fps = 0;
>>> +		lt6911uxe->cur_mode.link_freq = 0;
>>> +		v4l2_subdev_notify_event(&lt6911uxe->sd,
>>> +					 &lt6911uxe_ev_stream_end);
>>> +		break;
>>> +
>>> +	default:
>>> +		return  -ENOLINK;
>>> +	}
>>> +
>>> +	return ret;
>>> +}
>>> +
>>> +static int lt6911uxe_init_controls(struct lt6911uxe *lt6911uxe)
>>> +{
>>> +	struct v4l2_ctrl_handler *ctrl_hdlr;
>>> +	s64 pixel_rate;
>>> +	int ret;
>>> +
>>> +	ctrl_hdlr = &lt6911uxe->ctrl_handler;
>>> +	ret = v4l2_ctrl_handler_init(ctrl_hdlr, 8);
>>> +	if (ret)
>>> +		return ret;
>>> +
>>> +	lt6911uxe->link_freq = v4l2_ctrl_new_std(ctrl_hdlr, NULL,
>>> +						 V4L2_CID_CUR_LINK_FREQ, 0,
>>> +						 LT6911UXE_MAX_LINK_FREQ, 1,
>>> +						 lt6911uxe->cur_mode.link_freq);
>>> +
>>> +	pixel_rate = get_pixel_rate(lt6911uxe);
>>> +	lt6911uxe->pixel_rate = v4l2_ctrl_new_std(ctrl_hdlr, NULL,
>>> +						  V4L2_CID_PIXEL_RATE,
>>> +						  pixel_rate, pixel_rate, 1,
>>> +						  pixel_rate);
>>> +
>>> +	if (ctrl_hdlr->error) {
>>> +		ret = ctrl_hdlr->error;
>>> +		goto hdlr_free;
>>> +	}
>>> +	lt6911uxe->sd.ctrl_handler = ctrl_hdlr;
>>> +
>>> +	return 0;
>>> +
>>> +hdlr_free:
>>> +	v4l2_ctrl_handler_free(ctrl_hdlr);
>>> +	return ret;
>>> +}
>>> +
>>> +static void lt6911uxe_update_pad_format(const struct lt6911uxe_mode *mode,
>>> +					struct v4l2_mbus_framefmt *fmt)
>>> +{
>>> +	fmt->width = mode->width;
>>> +	fmt->height = mode->height;
>>> +	fmt->code = mode->code;
>>> +	fmt->field = V4L2_FIELD_NONE;
>>> +}
>>> +
>>> +static int lt6911uxe_enable_streams(struct v4l2_subdev *sd,
>>> +				    struct v4l2_subdev_state *state,
>>> +				    u32 pad, u64 streams_mask)
>>> +{
>>> +	struct i2c_client *client = v4l2_get_subdevdata(sd);
>>> +	struct lt6911uxe *lt6911uxe = to_lt6911uxe(sd);
>>> +	int ret;
>>> +
>>> +	ret = pm_runtime_resume_and_get(&client->dev);
>>> +	if (ret < 0)
>>> +		return ret;
>>> +
>>> +	cci_write(lt6911uxe->regmap, REG_MIPI_TX_CTRL, 0x1, &ret);
>>> +	if (ret) {
>>> +		dev_err(&client->dev, "failed to start stream: %d\n", ret);
>>> +		goto err_rpm_put;
>>> +	}
>>> +
>>> +	return 0;
>>> +
>>> +err_rpm_put:
>>> +	pm_runtime_put(&client->dev);
>>> +	return ret;
>>> +}
>>> +
>>> +static int lt6911uxe_disable_streams(struct v4l2_subdev *sd,
>>> +				     struct v4l2_subdev_state *state,
>>> +				     u32 pad, u64 streams_mask)
>>> +{
>>> +	struct lt6911uxe *lt6911uxe = to_lt6911uxe(sd);
>>> +	struct i2c_client *client = v4l2_get_subdevdata(&lt6911uxe->sd);
>>> +	int ret;
>>> +
>>> +	ret = cci_write(lt6911uxe->regmap, REG_MIPI_TX_CTRL, 0x0, NULL);
>>> +	if (ret)
>>> +		dev_err(&client->dev, "failed to stop stream: %d\n", ret);
>>> +
>>> +	pm_runtime_put(&client->dev);
>>> +	return 0;
>>> +}
>>> +
>>> +static int lt6911uxe_set_format(struct v4l2_subdev *sd,
>>> +				struct v4l2_subdev_state *sd_state,
>>> +				struct v4l2_subdev_format *fmt)
>>> +{
>>> +	struct lt6911uxe *lt6911uxe = to_lt6911uxe(sd);
>>> +	u64 pixel_rate, link_freq;
>>> +
>>> +	lt6911uxe_update_pad_format(&lt6911uxe->cur_mode, &fmt->format);
>>> +	*v4l2_subdev_state_get_format(sd_state, fmt->pad) = fmt->format;
>>> +	if (fmt->which == V4L2_SUBDEV_FORMAT_TRY)
>>> +		return 0;
>>> +
>>> +	pixel_rate = get_pixel_rate(lt6911uxe);
>>> +	__v4l2_ctrl_modify_range(lt6911uxe->pixel_rate, pixel_rate,
>>> +				 pixel_rate, 1, pixel_rate);
>>> +
>>> +	link_freq = lt6911uxe->cur_mode.link_freq;
>>> +	__v4l2_ctrl_modify_range(lt6911uxe->link_freq, link_freq,
>>> +				 link_freq, 1, link_freq);
>>> +
>>> +	return 0;
>>> +}
>>> +
>>> +static int lt6911uxe_enum_mbus_code(struct v4l2_subdev *sd,
>>> +				    struct v4l2_subdev_state *sd_state,
>>> +				    struct v4l2_subdev_mbus_code_enum *code)
>>> +{
>>> +	struct lt6911uxe *lt6911uxe = to_lt6911uxe(sd);
>>> +
>>> +	if (code->index)
>>> +		return -EINVAL;
>>> +
>>> +	code->code = lt6911uxe->cur_mode.code;
>>> +
>>> +	return 0;
>>> +}
>>> +
>>> +static int lt6911uxe_enum_frame_size(struct v4l2_subdev *sd,
>>> +				     struct v4l2_subdev_state *sd_state,
>>> +				     struct v4l2_subdev_frame_size_enum *fse)
>>> +{
>>> +	struct lt6911uxe *lt6911uxe = to_lt6911uxe(sd);
>>> +
>>> +	if (fse->index != 0)
>>> +		return -EINVAL;
>>> +
>>> +	if (fse->code != MEDIA_BUS_FMT_UYVY8_1X16)
>>> +		return -EINVAL;
>>> +
>>> +	fse->min_width = lt6911uxe->cur_mode.width;
>>> +	fse->max_width = fse->min_width;
>>> +	fse->min_height = lt6911uxe->cur_mode.height;
>>> +	fse->max_height = fse->min_height;
>>> +
>>> +	return 0;
>>> +}
>>> +
>>> +static int lt6911uxe_enum_frame_interval(struct v4l2_subdev *sd,
>>> +		struct v4l2_subdev_state *sd_state,
>>> +		struct v4l2_subdev_frame_interval_enum *fie)
>>> +{
>>> +	struct lt6911uxe *lt6911uxe = to_lt6911uxe(sd);
>>> +
>>> +	if (fie->index != 0)
>>> +		return -EINVAL;
>>> +
>>> +	fie->interval.numerator = 1;
>>> +	fie->interval.denominator = lt6911uxe->cur_mode.fps;
>>> +
>>> +	return 0;
>>> +}
>>> +
>>> +static int lt6911uxe_init_state(struct v4l2_subdev *sd,
>>> +				struct v4l2_subdev_state *sd_state)
>>> +{
>>> +	struct v4l2_subdev_format fmt = {
>>> +		.which = V4L2_SUBDEV_FORMAT_TRY,
>>> +		.pad = 0,
>>> +		.format = {
>>> +			.code = MEDIA_BUS_FMT_UYVY8_1X16,
>>> +			.width = LT6911UXE_DEFAULT_WIDTH,
>>> +			.height = LT6911UXE_DEFAULT_HEIGHT,
>>> +		},
>>> +	};
>>> +
>>> +	return lt6911uxe_set_format(sd, sd_state, &fmt);
>>> +}
>>> +
>>> +static const struct v4l2_subdev_video_ops lt6911uxe_video_ops = {
>>> +	.s_stream = v4l2_subdev_s_stream_helper,
>>> +};
>>> +
>>> +static const struct v4l2_subdev_pad_ops lt6911uxe_pad_ops = {
>>> +	.set_fmt = lt6911uxe_set_format,
>>> +	.get_fmt = v4l2_subdev_get_fmt,
>>> +	.enable_streams = lt6911uxe_enable_streams,
>>> +	.disable_streams = lt6911uxe_disable_streams,
>>> +	.enum_mbus_code = lt6911uxe_enum_mbus_code,
>>> +	.enum_frame_size = lt6911uxe_enum_frame_size,
>>> +	.enum_frame_interval = lt6911uxe_enum_frame_interval,
>>> +};
>>> +
>>> +static const struct v4l2_subdev_core_ops lt6911uxe_subdev_core_ops = {
>>> +	.subscribe_event = v4l2_ctrl_subdev_subscribe_event,
>>> +	.unsubscribe_event = v4l2_event_subdev_unsubscribe,
>>> +};
>>> +
>>> +static const struct v4l2_subdev_ops lt6911uxe_subdev_ops = {
>>> +	.core = &lt6911uxe_subdev_core_ops,
>>> +	.video = &lt6911uxe_video_ops,
>>> +	.pad = &lt6911uxe_pad_ops,
>>> +};
>>> +
>>> +static const struct media_entity_operations lt6911uxe_subdev_entity_ops = {
>>> +	.link_validate = v4l2_subdev_link_validate,
>>> +};
>>> +
>>> +static const struct v4l2_subdev_internal_ops lt6911uxe_internal_ops = {
>>> +	.init_state = lt6911uxe_init_state,
>>> +};
>>> +
>>> +static int lt6911uxe_fwnode_parse(struct lt6911uxe *lt6911uxe,
>>> +				  struct device *dev)
>>> +{
>>> +	struct fwnode_handle *endpoint;
>>> +	struct v4l2_fwnode_endpoint bus_cfg = {
>>> +		.bus_type = V4L2_MBUS_CSI2_DPHY,
>>> +	};
>>> +	int ret;
>>> +
>>> +	endpoint = fwnode_graph_get_endpoint_by_id(dev_fwnode(dev), 0, 0,
>>> +						   FWNODE_GRAPH_ENDPOINT_NEXT);
>>> +	if (!endpoint)
>>> +		return dev_err_probe(dev, -EPROBE_DEFER,
>>> +				     "endpoint node not found\n");
>>> +
>>> +	ret = v4l2_fwnode_endpoint_parse(endpoint, &bus_cfg);
>>> +	fwnode_handle_put(endpoint);
>>> +	if (ret) {
>>> +		dev_err(dev, "failed to parse endpoint node: %d\n", ret);
>>> +		goto out_err;
>>> +	}
>>> +
>>> +	/*
>>> +	 * Check the number of MIPI CSI2 data lanes,
>>> +	 * lt6911uxe only support 4 lanes.
>>> +	 */
>>> +	if (bus_cfg.bus.mipi_csi2.num_data_lanes != LT6911UXE_DEFAULT_LANES) {
>>> +		dev_err(dev, "only 4 data lanes are currently supported\n");
>>> +		goto out_err;
>>> +	}
>>> +
>>> +	return 0;
>>> +
>>> +out_err:
>>> +	v4l2_fwnode_endpoint_free(&bus_cfg);
>>> +	return ret;
>>> +}
>>> +
>>> +static int lt6911uxe_identify_module(struct lt6911uxe *lt6911uxe,
>>> +				     struct device *dev)
>>> +{
>>> +	u64 val;
>>> +	int ret = 0;
>>> +
>>> +	/* Chip ID should be confirmed when the I2C slave is active */
>>> +	cci_write(lt6911uxe->regmap, REG_ENABLE_I2C, 0x1, &ret);
>>> +	cci_read(lt6911uxe->regmap, REG_CHIP_ID, &val, &ret);
>>> +	cci_write(lt6911uxe->regmap, REG_ENABLE_I2C, 0x0, &ret);
>>> +	if (ret)
>>> +		return dev_err_probe(dev, ret, "fail to read chip id\n");
>>> +
>>> +	if (val != LT6911UXE_CHIP_ID) {
>>> +		return dev_err_probe(dev, -ENXIO, "chip id mismatch: %x!=%x\n",
>>> +				     LT6911UXE_CHIP_ID, (u16)val);
>>> +	}
>>> +
>>> +	return 0;
>>> +}
>>> +
>>> +static irqreturn_t lt6911uxe_threaded_irq_fn(int irq, void *dev_id)
>>> +{
>>> +	struct v4l2_subdev *sd = dev_id;
>>> +	struct lt6911uxe *lt6911uxe = to_lt6911uxe(sd);
>>> +	struct v4l2_subdev_state *state;
>>> +
>>> +	state = v4l2_subdev_lock_and_get_active_state(sd);
>>> +	lt6911uxe_status_update(lt6911uxe);
>>> +	v4l2_subdev_unlock_state(state);
>>> +
>>> +	return IRQ_HANDLED;
>>> +}
>>> +
>>> +static void lt6911uxe_remove(struct i2c_client *client)
>>> +{
>>> +	struct v4l2_subdev *sd = i2c_get_clientdata(client);
>>> +	struct lt6911uxe *lt6911uxe = to_lt6911uxe(sd);
>>> +
>>> +	free_irq(gpiod_to_irq(lt6911uxe->irq_gpio), lt6911uxe);
>>> +	v4l2_async_unregister_subdev(sd);
>>> +	v4l2_subdev_cleanup(sd);
>>> +	media_entity_cleanup(&sd->entity);
>>> +	v4l2_ctrl_handler_free(&lt6911uxe->ctrl_handler);
>>> +	pm_runtime_disable(&client->dev);
>>> +	pm_runtime_set_suspended(&client->dev);
>>> +}
>>> +
>>> +static int lt6911uxe_probe(struct i2c_client *client)
>>> +{
>>> +	struct lt6911uxe *lt6911uxe;
>>> +	struct device *dev = &client->dev;
>>> +	u64 irq_pin_flags;
>>> +	int ret;
>>> +
>>> +	lt6911uxe = devm_kzalloc(dev, sizeof(*lt6911uxe), GFP_KERNEL);
>>> +	if (!lt6911uxe)
>>> +		return -ENOMEM;
>>> +
>>> +	/* define default mode: 4k@60fps, changed when interrupt occurs. */
>>> +	lt6911uxe->cur_mode = default_mode;
>>> +
>>> +	lt6911uxe->regmap = devm_regmap_init_i2c(client,
>>> +						 &lt9611uxe_regmap_config);
>>> +	if (IS_ERR(lt6911uxe->regmap))
>>> +		return dev_err_probe(dev, PTR_ERR(lt6911uxe->regmap),
>>> +				     "failed to init CCI\n");
>>> +
>>> +	v4l2_i2c_subdev_init(&lt6911uxe->sd, client, &lt6911uxe_subdev_ops);
>>> +
>>> +	lt6911uxe->reset_gpio = devm_gpiod_get(dev, "reset", GPIOD_IN);
>>> +	if (IS_ERR(lt6911uxe->reset_gpio))
>>> +		return dev_err_probe(dev, PTR_ERR(lt6911uxe->reset_gpio),
>>> +				     "failed to get reset gpio\n");
>>> +
>>> +	lt6911uxe->irq_gpio = devm_gpiod_get(dev, "readystat", GPIOD_IN);
>>> +	if (IS_ERR(lt6911uxe->irq_gpio))
>>> +		return dev_err_probe(dev, PTR_ERR(lt6911uxe->irq_gpio),
>>> +				     "failed to get ready_stat gpio\n");
>>> +
>>> +	ret = lt6911uxe_fwnode_parse(lt6911uxe, dev);
>>> +	if (ret)
>>> +		return ret;
>>> +
>>> +	usleep_range(10000, 10500);
>>> +
>>> +	ret = lt6911uxe_identify_module(lt6911uxe, dev);
>>> +	if (ret)
>>> +		return dev_err_probe(dev, ret, "failed to find chip\n");
>>> +
>>> +	ret = lt6911uxe_init_controls(lt6911uxe);
>>> +	if (ret)
>>> +		return dev_err_probe(dev, ret, "failed to init control\n");
>>> +
>>> +	lt6911uxe->sd.dev = dev;
>>> +	lt6911uxe->sd.internal_ops = &lt6911uxe_internal_ops;
>>> +	lt6911uxe->sd.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE |
>>> +			       V4L2_SUBDEV_FL_HAS_EVENTS;
>>> +	lt6911uxe->sd.entity.ops = &lt6911uxe_subdev_entity_ops;
>>> +	lt6911uxe->sd.entity.function = MEDIA_ENT_F_VID_IF_BRIDGE;
>>> +	lt6911uxe->pad.flags = MEDIA_PAD_FL_SOURCE;
>>> +	ret = media_entity_pads_init(&lt6911uxe->sd.entity, 1, &lt6911uxe->pad);
>>> +	if (ret) {
>>> +		dev_err(dev, "failed to init entity pads: %d\n", ret);
>>> +		goto v4l2_ctrl_handler_free;
>>> +	}
>>> +
>>> +	/*
>>> +	 * Device is already turned on by i2c-core with ACPI domain PM.
>>> +	 * Enable runtime PM and turn off the device.
>>> +	 */
>>> +	pm_runtime_set_active(dev);
>>> +	pm_runtime_enable(dev);
>>> +	pm_runtime_idle(dev);
>>> +
>>> +	ret = v4l2_subdev_init_finalize(&lt6911uxe->sd);
>>> +	if (ret) {
>>> +		dev_err(dev, "failed to init v4l2 subdev: %d\n", ret);
>>> +		goto media_entity_cleanup;
>>> +	}
>>> +
>>> +	/* Setting irq */
>>> +	irq_pin_flags = IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING |
>>> +			IRQF_ONESHOT;
>>> +
>>> +	ret = request_threaded_irq(gpiod_to_irq(lt6911uxe->irq_gpio), NULL,
>>> +				   lt6911uxe_threaded_irq_fn,
>>> +				   irq_pin_flags, NULL, lt6911uxe);
>>> +	if (ret) {
>>> +		dev_err(dev, "failed to request IRQ: %d\n", ret);
>>> +		goto subdev_cleanup;
>>> +	}
>>> +
>>> +	ret = v4l2_async_register_subdev_sensor(&lt6911uxe->sd);
>>> +	if (ret) {
>>> +		dev_err(dev, "failed to register V4L2 subdev: %d\n", ret);
>>> +		goto free_irq;
>>> +	}
>>> +
>>> +	return 0;
>>> +
>>> +free_irq:
>>> +	free_irq(gpiod_to_irq(lt6911uxe->irq_gpio), lt6911uxe);
>>> +
>>> +subdev_cleanup:
>>> +	v4l2_subdev_cleanup(&lt6911uxe->sd);
>>> +
>>> +media_entity_cleanup:
>>> +	pm_runtime_disable(dev);
>>> +	pm_runtime_set_suspended(dev);
>>> +	media_entity_cleanup(&lt6911uxe->sd.entity);
>>> +
>>> +v4l2_ctrl_handler_free:
>>> +	v4l2_ctrl_handler_free(lt6911uxe->sd.ctrl_handler);
>>> +	return ret;
>>> +}
>>> +
>>> +static const struct acpi_device_id lt6911uxe_acpi_ids[] = {
>>> +	{ "INTC10C5" },
>>> +	{}
>>> +};
>>> +MODULE_DEVICE_TABLE(acpi, lt6911uxe_acpi_ids);
>>> +
>>> +static struct i2c_driver lt6911uxe_i2c_driver = {
>>> +	.driver = {
>>> +		.name = "lt6911uxe",
>>> +		.acpi_match_table = ACPI_PTR(lt6911uxe_acpi_ids),
>>> +	},
>>> +	.probe = lt6911uxe_probe,
>>> +	.remove = lt6911uxe_remove,
>>> +};
>>> +
>>> +module_i2c_driver(lt6911uxe_i2c_driver);
>>> +
>>> +MODULE_AUTHOR("Yan Dongcheng <dongcheng.yan@intel.com>");
>>> +MODULE_DESCRIPTION("Lontium lt6911uxe HDMI to MIPI Bridge Driver");
>>> +MODULE_LICENSE("GPL");
>>>
>>> base-commit: 2f87d0916ce0d2925cedbc9e8f5d6291ba2ac7b2

On 25/10/2024 08:49, Sakari Ailus wrote:
> Hi Hans,
> 
> On Wed, Oct 23, 2024 at 02:28:02PM +0200, Hans Verkuil wrote:
>> Hi Dongcheng,
>>
>> Since this is an HDMI receiver, you need to implement the DV Timings API.
> 
> "Must"? Why?

The DV Timings API is used to deal with the HDMI interface part.

> 
> I don't know the tc358743 driver but it'd unlikely to work with current
> CSI-2 RX drivers. They expect the LINK_FREQ control for instance, not the
> DV timing API.
> <URL:https://hverkuil.home.xs4all.nl/spec/driver-api/tx-rx.html#transmitter-receiver>
> 

The tc358743 predates these controls. It just uses get_mbus_config. The CSI
configuration is defined in the dts:

Documentation/devicetree/bindings/media/i2c/tc358743.txt

It is fine to add support for these controls, but the DV Timings API to deal
with the HDMI interface is required for HDMI receivers.

The CSI lanes/frequencies are typically fixed for HDMI receivers (i.e. they
don't change if the resolution changes).

Regards,

	Hans