drivers/video/mt9m114.c - third_party/github/zephyrproject-rtos/zephyr - Git at Google

 /*
  * Copyright (c) 2019, Linaro Limited
  *
  * SPDX-License-Identifier: Apache-2.0
  */

 #define DT_DRV_COMPAT aptina_mt9m114
 #include <zephyr/kernel.h>
 #include <zephyr/device.h>

 #include <zephyr/sys/byteorder.h>

 #include <zephyr/drivers/video.h>
 #include <zephyr/drivers/i2c.h>

 #define LOG_LEVEL CONFIG_LOG_DEFAULT_LEVEL
 #include <zephyr/logging/log.h>
 LOG_MODULE_REGISTER(mt9m114);

 #define MT9M114_CHIP_ID_VAL				0x2481

 /* Sysctl registers */
 #define MT9M114_CHIP_ID					0x0000
 #define MT9M114_COMMAND_REGISTER			0x0080
 #define MT9M114_COMMAND_REGISTER_APPLY_PATCH		(1 << 0)
 #define MT9M114_COMMAND_REGISTER_SET_STATE		(1 << 1)
 #define MT9M114_COMMAND_REGISTER_REFRESH		(1 << 2)
 #define MT9M114_COMMAND_REGISTER_WAIT_FOR_EVENT		(1 << 3)
 #define MT9M114_COMMAND_REGISTER_OK			(1 << 15)
 #define MT9M114_PAD_CONTROL				0x0032
 #define MT9M114_RST_AND_MISC_CONTROL			0x001A

 /* Camera Control registers */
 #define MT9M114_CAM_OUTPUT_FORMAT			0xc86c

 /* System Manager registers */
 #define MT9M114_SYSMGR_NEXT_STATE			0xdc00
 #define MT9M114_SYSMGR_CURRENT_STATE			0xdc01
 #define MT9M114_SYSMGR_CMD_STATUS			0xdc02

 /* System States */
 #define MT9M114_SYS_STATE_ENTER_CONFIG_CHANGE		0x28
 #define MT9M114_SYS_STATE_STREAMING			0x31
 #define MT9M114_SYS_STATE_START_STREAMING		0x34
 #define MT9M114_SYS_STATE_ENTER_SUSPEND			0x40
 #define MT9M114_SYS_STATE_SUSPENDED			0x41
 #define MT9M114_SYS_STATE_ENTER_STANDBY			0x50
 #define MT9M114_SYS_STATE_STANDBY			0x52
 #define MT9M114_SYS_STATE_LEAVE_STANDBY			0x54

 struct mt9m114_config {
 	struct i2c_dt_spec i2c;
 };

 struct mt9m114_data {
 	struct video_format fmt;
 };

 struct mt9m114_reg {
 	uint16_t addr;
 	uint16_t value_size;
 	uint32_t value;
 };

 static struct mt9m114_reg mt9m114_vga_24mhz_pll[] = {
 	{ 0x98E,  2, 0x1000	},
 	{ 0xC97E, 2, 0x01	}, /* cam_sysctl_pll_enable = 1 */
 	{ 0xC980, 2, 0x0120	}, /* cam_sysctl_pll_divider_m_n = 288 */
 	{ 0xC982, 2, 0x0700	}, /* cam_sysctl_pll_divider_p = 1792 */
 	{ 0xC984, 2, 0x8000	}, /* cam_port_output_control = 32776 */
 	{ 0xC800, 2, 0x0000	}, /* cam_sensor_cfg_y_addr_start = 0 */
 	{ 0xC802, 2, 0x0000	}, /* cam_sensor_cfg_x_addr_start = 0 */
 	{ 0xC804, 2, 0x03CD	}, /* cam_sensor_cfg_y_addr_end = 973 */
 	{ 0xC806, 2, 0x050D	}, /* cam_sensor_cfg_x_addr_end = 1293 */
 	{ 0xC808, 4, 0x2DC6C00	}, /* cam_sensor_cfg_pixclk = 48000000 */
 	{ 0xC80C, 2, 0x0001	}, /* cam_sensor_cfg_row_speed = 1 */
 	{ 0xC80E, 2, 0x00DB	}, /* cam_sensor_cfg_fine_integ_min = 219 */
 	{ 0xC810, 2, 0x07C2	}, /* cam_sensor_cfg_fine_integ_max = 1986 */
 	{ 0xC812, 2, 0x02FE	}, /* cam_sensor_cfg_frame_length_lines = 766 */
 	{ 0xC814, 2, 0x0845	}, /* cam_sensor_cfg_line_length_pck = 2117 */
 	{ 0xC816, 2, 0x0060	}, /* cam_sensor_cfg_fine_correction = 96 */
 	{ 0xC818, 2, 0x01E3	}, /* cam_sensor_cfg_cpipe_last_row = 483 */
 	{ 0xC826, 2, 0x0020	}, /* cam_sensor_cfg_reg_0_data = 32 */
 	{ 0xC834, 2, 0x0110	}, /* cam_sensor_control_read_mode = 272 */
 	{ 0xC854, 2, 0x0000	}, /* cam_crop_window_xoffset = 0 */
 	{ 0xC856, 2, 0x0000	}, /* cam_crop_window_yoffset = 0 */
 	{ 0xC858, 2, 0x0280	}, /* cam_crop_window_width = 640 */
 	{ 0xC85A, 2, 0x01E0	}, /* cam_crop_window_height = 480 */
 	{ 0xC85C, 1, 0x03	}, /* cam_crop_cropmode = 3 */
 	{ 0xC868, 2, 0x0280	}, /* cam_output_width = 640 */
 	{ 0xC86A, 2, 0x01E0	}, /* cam_output_height = 480 */
 	{ 0xC878, 1, 0x00	}, /* cam_aet_aemode = 0 */
 	{ 0xC88C, 2, 0x1D9A	}, /* cam_aet_max_frame_rate = 7578 */
 	{ 0xC914, 2, 0x0000	}, /* cam_stat_awb_clip_window_xstart = 0 */
 	{ 0xC88E, 2, 0x1D9A	}, /* cam_aet_min_frame_rate = 7578 */
 	{ 0xC916, 2, 0x0000	}, /* cam_stat_awb_clip_window_ystart = 0 */
 	{ 0xC918, 2, 0x027F	}, /* cam_stat_awb_clip_window_xend = 639 */
 	{ 0xC91A, 2, 0x01DF	}, /* cam_stat_awb_clip_window_yend = 479 */
 	{ 0xC91C, 2, 0x0000	}, /* cam_stat_ae_initial_window_xstart = 0 */
 	{ 0xC91E, 2, 0x0000	}, /* cam_stat_ae_initial_window_ystart = 0 */
 	{ 0xC920, 2, 0x007F	}, /* cam_stat_ae_initial_window_xend = 127 */
 	{ 0xC922, 2, 0x005F	}, /* cam_stat_ae_initial_window_yend = 95 */
 	{ /* NULL terminated */ }
 };

 static inline int i2c_burst_read16_dt(const struct i2c_dt_spec *spec,
 				   uint16_t start_addr, uint8_t *buf, uint32_t num_bytes)
 {
 	uint8_t addr_buffer[2];

 	addr_buffer[1] = start_addr & 0xFF;
 	addr_buffer[0] = start_addr >> 8;
 	return i2c_write_read_dt(spec, addr_buffer, sizeof(addr_buffer), buf, num_bytes);
 }

 static inline int i2c_burst_write16_dt(const struct i2c_dt_spec *spec,
 				    uint16_t start_addr, const uint8_t *buf,
 				    uint32_t num_bytes)
 {
 	uint8_t addr_buffer[2];
 	struct i2c_msg msg[2];

 	addr_buffer[1] = start_addr & 0xFF;
 	addr_buffer[0] = start_addr >> 8;
 	msg[0].buf = addr_buffer;
 	msg[0].len = 2U;
 	msg[0].flags = I2C_MSG_WRITE;

 	msg[1].buf = (uint8_t *)buf;
 	msg[1].len = num_bytes;
 	msg[1].flags = I2C_MSG_WRITE | I2C_MSG_STOP;

 	return i2c_transfer_dt(spec, msg, 2);
 }

 static int mt9m114_write_reg(const struct device *dev, uint16_t reg_addr,
 			     uint8_t reg_size,
 			     void *value)
 {
 	const struct mt9m114_config *cfg = dev->config;

 	switch (reg_size) {
 	case 2:
 		*(uint16_t *)value = sys_cpu_to_be16(*(uint16_t *)value);
 		break;
 	case 4:
 		*(uint16_t *)value = sys_cpu_to_be32(*(uint16_t *)value);
 		break;
 	case 1:
 		break;
 	default:
 		return -ENOTSUP;
 	}

 	return i2c_burst_write16_dt(&cfg->i2c, reg_addr, value, reg_size);
 }

 static int mt9m114_read_reg(const struct device *dev, uint16_t reg_addr,
 			    uint8_t reg_size,
 			    void *value)
 {
 	const struct mt9m114_config *cfg = dev->config;
 	int err;

 	if (reg_size > 4) {
 		return -ENOTSUP;
 	}

 	err = i2c_burst_read16_dt(&cfg->i2c, reg_addr, value, reg_size);
 	if (err) {
 		return err;
 	}

 	switch (reg_size) {
 	case 2:
 		*(uint16_t *)value = sys_be16_to_cpu(*(uint16_t *)value);
 		break;
 	case 4:
 		*(uint32_t *)value = sys_be32_to_cpu(*(uint32_t *)value);
 		break;
 	case 1:
 		break;
 	default:
 		return -ENOTSUP;
 	}

 	return 0;
 }

 static int mt9m114_write_all(const struct device *dev,
 			     struct mt9m114_reg *reg)
 {
 	int i = 0;

 	while (reg[i].value_size) {
 		int err;

 		err = mt9m114_write_reg(dev, reg[i].addr, reg[i].value_size,
 					&reg[i].value);
 		if (err) {
 			return err;
 		}

 		i++;
 	}

 	return 0;
 }

 static int mt9m114_set_state(const struct device *dev, uint8_t state)
 {
 	uint16_t val;
 	int err;

 	/* Set next state. */
 	mt9m114_write_reg(dev, MT9M114_SYSMGR_NEXT_STATE, 1, &state);

 	/* Check that the FW is ready to accept a new command. */
 	while (1) {
 		err = mt9m114_read_reg(dev, MT9M114_COMMAND_REGISTER, 2, &val);
 		if (err) {
 			return err;
 		}

 		if (!(val & MT9M114_COMMAND_REGISTER_SET_STATE)) {
 			break;
 		}

 		k_sleep(K_MSEC(1));
 	}

 	/* Issue the Set State command. */
 	val = MT9M114_COMMAND_REGISTER_SET_STATE | MT9M114_COMMAND_REGISTER_OK;
 	mt9m114_write_reg(dev, MT9M114_COMMAND_REGISTER, 2, &val);

 	/* Wait for the FW to complete the command. */
 	while (1) {
 		err = mt9m114_read_reg(dev, MT9M114_COMMAND_REGISTER, 2, &val);
 		if (err) {
 			return err;
 		}

 		if (!(val & MT9M114_COMMAND_REGISTER_SET_STATE)) {
 			break;
 		}

 		k_sleep(K_MSEC(1));
 	}

 	/* Check the 'OK' bit to see if the command was successful. */
 	err = mt9m114_read_reg(dev, MT9M114_COMMAND_REGISTER, 2, &val);
 	if (err || !(val & MT9M114_COMMAND_REGISTER_OK)) {
 		return -EIO;
 	}

 	return 0;
 }

 static int mt9m114_set_fmt(const struct device *dev,
 			   enum video_endpoint_id ep,
 			   struct video_format *fmt)
 {
 	struct mt9m114_data *drv_data = dev->data;
 	uint16_t output_format;
 	int ret;

 	/* we only support one format for now (VGA RGB565) */
 	if (fmt->pixelformat != VIDEO_PIX_FMT_RGB565 || fmt->height != 480 ||
 	    fmt->width != 640) {
 		return -ENOTSUP;
 	}

 	if (!memcmp(&drv_data->fmt, fmt, sizeof(drv_data->fmt))) {
 		/* nothing to do */
 		return 0;
 	}

 	drv_data->fmt = *fmt;

 	/* Configure Sensor */
 	ret = mt9m114_write_all(dev, mt9m114_vga_24mhz_pll);
 	if (ret) {
 		LOG_ERR("Unable to write mt9m114 config");
 		return ret;
 	}

 	/* Set output format */
 	output_format = ((1U << 8U) | (1U << 1U)); /* RGB565 */
 	ret = mt9m114_write_reg(dev, MT9M114_CAM_OUTPUT_FORMAT,
 				sizeof(output_format), &output_format);
 	if (ret) {
 		LOG_ERR("Unable to set output format");
 		return ret;
 	}

 	/* Apply Config */
 	mt9m114_set_state(dev, MT9M114_SYS_STATE_ENTER_CONFIG_CHANGE);

 	return 0;
 }

 static int mt9m114_get_fmt(const struct device *dev,
 			   enum video_endpoint_id ep,
 			   struct video_format *fmt)
 {
 	struct mt9m114_data *drv_data = dev->data;

 	*fmt = drv_data->fmt;

 	return 0;
 }

 static int mt9m114_stream_start(const struct device *dev)
 {
 	return mt9m114_set_state(dev, MT9M114_SYS_STATE_START_STREAMING);
 }

 static int mt9m114_stream_stop(const struct device *dev)
 {
 	return mt9m114_set_state(dev, MT9M114_SYS_STATE_ENTER_SUSPEND);
 }

 static const struct video_format_cap fmts[] = {
 	{
 		.pixelformat = VIDEO_PIX_FMT_RGB565,
 		.width_min = 640,
 		.width_max = 640,
 		.height_min = 480,
 		.height_max = 480,
 		.width_step = 0,
 		.height_step = 0,
 	},
 	{ 0 }
 };

 static int mt9m114_get_caps(const struct device *dev,
 			    enum video_endpoint_id ep,
 			    struct video_caps *caps)
 {
 	caps->format_caps = fmts;
 	return 0;
 }

 static const struct video_driver_api mt9m114_driver_api = {
 	.set_format = mt9m114_set_fmt,
 	.get_format = mt9m114_get_fmt,
 	.get_caps = mt9m114_get_caps,
 	.stream_start = mt9m114_stream_start,
 	.stream_stop = mt9m114_stream_stop,
 };

 static int mt9m114_init(const struct device *dev)
 {
 	struct video_format fmt;
 	uint16_t val;
 	int ret;

 	/* no power control, wait for camera ready */
 	k_sleep(K_MSEC(100));

 	ret = mt9m114_read_reg(dev, MT9M114_CHIP_ID, sizeof(val), &val);
 	if (ret) {
 		LOG_ERR("Unable to read chip ID");
 		return -ENODEV;
 	}

 	if (val != MT9M114_CHIP_ID_VAL) {
 		LOG_ERR("Wrong ID: %04x (exp %04x)", val, MT9M114_CHIP_ID_VAL);
 		return -ENODEV;
 	}

 	/* set default/init format VGA RGB565 */
 	fmt.pixelformat = VIDEO_PIX_FMT_RGB565;
 	fmt.width = 640;
 	fmt.height = 480;
 	fmt.pitch = 640 * 2;

 	ret = mt9m114_set_fmt(dev, VIDEO_EP_OUT, &fmt);
 	if (ret) {
 		LOG_ERR("Unable to configure default format");
 		return -EIO;
 	}

 	/* Suspend any stream */
 	mt9m114_set_state(dev, MT9M114_SYS_STATE_ENTER_SUSPEND);

 	return 0;
 }

 #if 1 /* Unique Instance */

 static const struct mt9m114_config mt9m114_cfg_0 = {
 	.i2c = I2C_DT_SPEC_INST_GET(0),
 };

 static struct mt9m114_data mt9m114_data_0;

 static int mt9m114_init_0(const struct device *dev)
 {
 	const struct mt9m114_config *cfg = dev->config;

 	if (!device_is_ready(cfg->i2c.bus)) {
 		LOG_ERR("Bus device is not ready");
 		return -ENODEV;
 	}

 	return mt9m114_init(dev);
 }

 DEVICE_DT_INST_DEFINE(0, &mt9m114_init_0, NULL,
 		    &mt9m114_data_0, &mt9m114_cfg_0,
 		    POST_KERNEL, CONFIG_KERNEL_INIT_PRIORITY_DEVICE,
 		    &mt9m114_driver_api);
 #endif
	/*
	* Copyright (c) 2019, Linaro Limited
	*
	* SPDX-License-Identifier: Apache-2.0
	*/

	#define DT_DRV_COMPAT aptina_mt9m114
	#include <zephyr/kernel.h>
	#include <zephyr/device.h>

	#include <zephyr/sys/byteorder.h>

	#include <zephyr/drivers/video.h>
	#include <zephyr/drivers/i2c.h>

	#define LOG_LEVEL CONFIG_LOG_DEFAULT_LEVEL
	#include <zephyr/logging/log.h>
	LOG_MODULE_REGISTER(mt9m114);

	#define MT9M114_CHIP_ID_VAL 0x2481

	/* Sysctl registers */
	#define MT9M114_CHIP_ID 0x0000
	#define MT9M114_COMMAND_REGISTER 0x0080
	#define MT9M114_COMMAND_REGISTER_APPLY_PATCH (1 << 0)
	#define MT9M114_COMMAND_REGISTER_SET_STATE (1 << 1)
	#define MT9M114_COMMAND_REGISTER_REFRESH (1 << 2)
	#define MT9M114_COMMAND_REGISTER_WAIT_FOR_EVENT (1 << 3)
	#define MT9M114_COMMAND_REGISTER_OK (1 << 15)
	#define MT9M114_PAD_CONTROL 0x0032
	#define MT9M114_RST_AND_MISC_CONTROL 0x001A

	/* Camera Control registers */
	#define MT9M114_CAM_OUTPUT_FORMAT 0xc86c

	/* System Manager registers */
	#define MT9M114_SYSMGR_NEXT_STATE 0xdc00
	#define MT9M114_SYSMGR_CURRENT_STATE 0xdc01
	#define MT9M114_SYSMGR_CMD_STATUS 0xdc02

	/* System States */
	#define MT9M114_SYS_STATE_ENTER_CONFIG_CHANGE 0x28
	#define MT9M114_SYS_STATE_STREAMING 0x31
	#define MT9M114_SYS_STATE_START_STREAMING 0x34
	#define MT9M114_SYS_STATE_ENTER_SUSPEND 0x40
	#define MT9M114_SYS_STATE_SUSPENDED 0x41
	#define MT9M114_SYS_STATE_ENTER_STANDBY 0x50
	#define MT9M114_SYS_STATE_STANDBY 0x52
	#define MT9M114_SYS_STATE_LEAVE_STANDBY 0x54

	struct mt9m114_config {
	struct i2c_dt_spec i2c;
	};

	struct mt9m114_data {
	struct video_format fmt;
	};

	struct mt9m114_reg {
	uint16_t addr;
	uint16_t value_size;
	uint32_t value;
	};

	static struct mt9m114_reg mt9m114_vga_24mhz_pll[] = {
	{ 0x98E, 2, 0x1000 },
	{ 0xC97E, 2, 0x01 }, /* cam_sysctl_pll_enable = 1 */
	{ 0xC980, 2, 0x0120 }, /* cam_sysctl_pll_divider_m_n = 288 */
	{ 0xC982, 2, 0x0700 }, /* cam_sysctl_pll_divider_p = 1792 */
	{ 0xC984, 2, 0x8000 }, /* cam_port_output_control = 32776 */
	{ 0xC800, 2, 0x0000 }, /* cam_sensor_cfg_y_addr_start = 0 */
	{ 0xC802, 2, 0x0000 }, /* cam_sensor_cfg_x_addr_start = 0 */
	{ 0xC804, 2, 0x03CD }, /* cam_sensor_cfg_y_addr_end = 973 */
	{ 0xC806, 2, 0x050D }, /* cam_sensor_cfg_x_addr_end = 1293 */
	{ 0xC808, 4, 0x2DC6C00 }, /* cam_sensor_cfg_pixclk = 48000000 */
	{ 0xC80C, 2, 0x0001 }, /* cam_sensor_cfg_row_speed = 1 */
	{ 0xC80E, 2, 0x00DB }, /* cam_sensor_cfg_fine_integ_min = 219 */
	{ 0xC810, 2, 0x07C2 }, /* cam_sensor_cfg_fine_integ_max = 1986 */
	{ 0xC812, 2, 0x02FE }, /* cam_sensor_cfg_frame_length_lines = 766 */
	{ 0xC814, 2, 0x0845 }, /* cam_sensor_cfg_line_length_pck = 2117 */
	{ 0xC816, 2, 0x0060 }, /* cam_sensor_cfg_fine_correction = 96 */
	{ 0xC818, 2, 0x01E3 }, /* cam_sensor_cfg_cpipe_last_row = 483 */
	{ 0xC826, 2, 0x0020 }, /* cam_sensor_cfg_reg_0_data = 32 */
	{ 0xC834, 2, 0x0110 }, /* cam_sensor_control_read_mode = 272 */
	{ 0xC854, 2, 0x0000 }, /* cam_crop_window_xoffset = 0 */
	{ 0xC856, 2, 0x0000 }, /* cam_crop_window_yoffset = 0 */
	{ 0xC858, 2, 0x0280 }, /* cam_crop_window_width = 640 */
	{ 0xC85A, 2, 0x01E0 }, /* cam_crop_window_height = 480 */
	{ 0xC85C, 1, 0x03 }, /* cam_crop_cropmode = 3 */
	{ 0xC868, 2, 0x0280 }, /* cam_output_width = 640 */
	{ 0xC86A, 2, 0x01E0 }, /* cam_output_height = 480 */
	{ 0xC878, 1, 0x00 }, /* cam_aet_aemode = 0 */
	{ 0xC88C, 2, 0x1D9A }, /* cam_aet_max_frame_rate = 7578 */
	{ 0xC914, 2, 0x0000 }, /* cam_stat_awb_clip_window_xstart = 0 */
	{ 0xC88E, 2, 0x1D9A }, /* cam_aet_min_frame_rate = 7578 */
	{ 0xC916, 2, 0x0000 }, /* cam_stat_awb_clip_window_ystart = 0 */
	{ 0xC918, 2, 0x027F }, /* cam_stat_awb_clip_window_xend = 639 */
	{ 0xC91A, 2, 0x01DF }, /* cam_stat_awb_clip_window_yend = 479 */
	{ 0xC91C, 2, 0x0000 }, /* cam_stat_ae_initial_window_xstart = 0 */
	{ 0xC91E, 2, 0x0000 }, /* cam_stat_ae_initial_window_ystart = 0 */
	{ 0xC920, 2, 0x007F }, /* cam_stat_ae_initial_window_xend = 127 */
	{ 0xC922, 2, 0x005F }, /* cam_stat_ae_initial_window_yend = 95 */
	{ /* NULL terminated */ }
	};

	static inline int i2c_burst_read16_dt(const struct i2c_dt_spec *spec,
	uint16_t start_addr, uint8_t *buf, uint32_t num_bytes)
	{
	uint8_t addr_buffer[2];

	addr_buffer[1] = start_addr & 0xFF;
	addr_buffer[0] = start_addr >> 8;
	return i2c_write_read_dt(spec, addr_buffer, sizeof(addr_buffer), buf, num_bytes);
	}

	static inline int i2c_burst_write16_dt(const struct i2c_dt_spec *spec,
	uint16_t start_addr, const uint8_t *buf,
	uint32_t num_bytes)
	{
	uint8_t addr_buffer[2];
	struct i2c_msg msg[2];

	addr_buffer[1] = start_addr & 0xFF;
	addr_buffer[0] = start_addr >> 8;
	msg[0].buf = addr_buffer;
	msg[0].len = 2U;
	msg[0].flags = I2C_MSG_WRITE;

	msg[1].buf = (uint8_t *)buf;
	msg[1].len = num_bytes;
	msg[1].flags = I2C_MSG_WRITE \| I2C_MSG_STOP;

	return i2c_transfer_dt(spec, msg, 2);
	}

	static int mt9m114_write_reg(const struct device *dev, uint16_t reg_addr,
	uint8_t reg_size,
	void *value)
	{
	const struct mt9m114_config *cfg = dev->config;

	switch (reg_size) {
	case 2:
	(uint16_t )value = sys_cpu_to_be16((uint16_t )value);
	break;
	case 4:
	(uint16_t )value = sys_cpu_to_be32((uint16_t )value);
	break;
	case 1:
	break;
	default:
	return -ENOTSUP;
	}

	return i2c_burst_write16_dt(&cfg->i2c, reg_addr, value, reg_size);
	}

	static int mt9m114_read_reg(const struct device *dev, uint16_t reg_addr,
	uint8_t reg_size,
	void *value)
	{
	const struct mt9m114_config *cfg = dev->config;
	int err;

	if (reg_size > 4) {
	return -ENOTSUP;
	}

	err = i2c_burst_read16_dt(&cfg->i2c, reg_addr, value, reg_size);
	if (err) {
	return err;
	}

	switch (reg_size) {
	case 2:
	(uint16_t )value = sys_be16_to_cpu((uint16_t )value);
	break;
	case 4:
	(uint32_t )value = sys_be32_to_cpu((uint32_t )value);
	break;
	case 1:
	break;
	default:
	return -ENOTSUP;
	}

	return 0;
	}

	static int mt9m114_write_all(const struct device *dev,
	struct mt9m114_reg *reg)
	{
	int i = 0;

	while (reg[i].value_size) {
	int err;

	err = mt9m114_write_reg(dev, reg[i].addr, reg[i].value_size,
	&reg[i].value);
	if (err) {
	return err;
	}

	i++;
	}

	return 0;
	}

	static int mt9m114_set_state(const struct device *dev, uint8_t state)
	{
	uint16_t val;
	int err;

	/* Set next state. */
	mt9m114_write_reg(dev, MT9M114_SYSMGR_NEXT_STATE, 1, &state);

	/* Check that the FW is ready to accept a new command. */
	while (1) {
	err = mt9m114_read_reg(dev, MT9M114_COMMAND_REGISTER, 2, &val);
	if (err) {
	return err;
	}

	if (!(val & MT9M114_COMMAND_REGISTER_SET_STATE)) {
	break;
	}

	k_sleep(K_MSEC(1));
	}

	/* Issue the Set State command. */
	val = MT9M114_COMMAND_REGISTER_SET_STATE \| MT9M114_COMMAND_REGISTER_OK;
	mt9m114_write_reg(dev, MT9M114_COMMAND_REGISTER, 2, &val);

	/* Wait for the FW to complete the command. */
	while (1) {
	err = mt9m114_read_reg(dev, MT9M114_COMMAND_REGISTER, 2, &val);
	if (err) {
	return err;
	}

	if (!(val & MT9M114_COMMAND_REGISTER_SET_STATE)) {
	break;
	}

	k_sleep(K_MSEC(1));
	}

	/* Check the 'OK' bit to see if the command was successful. */
	err = mt9m114_read_reg(dev, MT9M114_COMMAND_REGISTER, 2, &val);
	if (err \|\| !(val & MT9M114_COMMAND_REGISTER_OK)) {
	return -EIO;
	}

	return 0;
	}

	static int mt9m114_set_fmt(const struct device *dev,
	enum video_endpoint_id ep,
	struct video_format *fmt)
	{
	struct mt9m114_data *drv_data = dev->data;
	uint16_t output_format;
	int ret;

	/* we only support one format for now (VGA RGB565) */
	if (fmt->pixelformat != VIDEO_PIX_FMT_RGB565 \|\| fmt->height != 480 \|\|
	fmt->width != 640) {
	return -ENOTSUP;
	}

	if (!memcmp(&drv_data->fmt, fmt, sizeof(drv_data->fmt))) {
	/* nothing to do */
	return 0;
	}

	drv_data->fmt = *fmt;

	/* Configure Sensor */
	ret = mt9m114_write_all(dev, mt9m114_vga_24mhz_pll);
	if (ret) {
	LOG_ERR("Unable to write mt9m114 config");
	return ret;
	}

	/* Set output format */
	output_format = ((1U << 8U) \| (1U << 1U)); /* RGB565 */
	ret = mt9m114_write_reg(dev, MT9M114_CAM_OUTPUT_FORMAT,
	sizeof(output_format), &output_format);
	if (ret) {
	LOG_ERR("Unable to set output format");
	return ret;
	}

	/* Apply Config */
	mt9m114_set_state(dev, MT9M114_SYS_STATE_ENTER_CONFIG_CHANGE);

	return 0;
	}

	static int mt9m114_get_fmt(const struct device *dev,
	enum video_endpoint_id ep,
	struct video_format *fmt)
	{
	struct mt9m114_data *drv_data = dev->data;

	*fmt = drv_data->fmt;

	return 0;
	}

	static int mt9m114_stream_start(const struct device *dev)
	{
	return mt9m114_set_state(dev, MT9M114_SYS_STATE_START_STREAMING);
	}

	static int mt9m114_stream_stop(const struct device *dev)
	{
	return mt9m114_set_state(dev, MT9M114_SYS_STATE_ENTER_SUSPEND);
	}

	static const struct video_format_cap fmts[] = {
	{
	.pixelformat = VIDEO_PIX_FMT_RGB565,
	.width_min = 640,
	.width_max = 640,
	.height_min = 480,
	.height_max = 480,
	.width_step = 0,
	.height_step = 0,
	},
	{ 0 }
	};

	static int mt9m114_get_caps(const struct device *dev,
	enum video_endpoint_id ep,
	struct video_caps *caps)
	{
	caps->format_caps = fmts;
	return 0;
	}

	static const struct video_driver_api mt9m114_driver_api = {
	.set_format = mt9m114_set_fmt,
	.get_format = mt9m114_get_fmt,
	.get_caps = mt9m114_get_caps,
	.stream_start = mt9m114_stream_start,
	.stream_stop = mt9m114_stream_stop,
	};

	static int mt9m114_init(const struct device *dev)
	{
	struct video_format fmt;
	uint16_t val;
	int ret;

	/* no power control, wait for camera ready */
	k_sleep(K_MSEC(100));

	ret = mt9m114_read_reg(dev, MT9M114_CHIP_ID, sizeof(val), &val);
	if (ret) {
	LOG_ERR("Unable to read chip ID");
	return -ENODEV;
	}

	if (val != MT9M114_CHIP_ID_VAL) {
	LOG_ERR("Wrong ID: %04x (exp %04x)", val, MT9M114_CHIP_ID_VAL);
	return -ENODEV;
	}

	/* set default/init format VGA RGB565 */
	fmt.pixelformat = VIDEO_PIX_FMT_RGB565;
	fmt.width = 640;
	fmt.height = 480;
	fmt.pitch = 640 * 2;

	ret = mt9m114_set_fmt(dev, VIDEO_EP_OUT, &fmt);
	if (ret) {
	LOG_ERR("Unable to configure default format");
	return -EIO;
	}

	/* Suspend any stream */
	mt9m114_set_state(dev, MT9M114_SYS_STATE_ENTER_SUSPEND);

	return 0;
	}

	#if 1 /* Unique Instance */

	static const struct mt9m114_config mt9m114_cfg_0 = {
	.i2c = I2C_DT_SPEC_INST_GET(0),
	};

	static struct mt9m114_data mt9m114_data_0;

	static int mt9m114_init_0(const struct device *dev)
	{
	const struct mt9m114_config *cfg = dev->config;

	if (!device_is_ready(cfg->i2c.bus)) {
	LOG_ERR("Bus device is not ready");
	return -ENODEV;
	}

	return mt9m114_init(dev);
	}

	DEVICE_DT_INST_DEFINE(0, &mt9m114_init_0, NULL,
	&mt9m114_data_0, &mt9m114_cfg_0,
	POST_KERNEL, CONFIG_KERNEL_INIT_PRIORITY_DEVICE,
	&mt9m114_driver_api);
	#endif