Re: [PATCH 2/2] media: video-i2c: add Melexis MLX90640 thermal camera support

[Hans Verkuil <hverkuil@xs4all.nl>]

On 11/01/2018 05:15 AM, Matt Ranostay wrote:
> Add initial support for MLX90640 thermal cameras which output an 32x24
> greyscale pixel image along with 2 rows of coefficent data.
> 
> Because of this the data outputed is really 32x26 and needs the two rows
> removed after using the coefficent information to generate processed
> images in userspace.
> 
> Signed-off-by: Matt Ranostay <matt.ranostay@konsulko.com>
> ---
>  drivers/media/i2c/Kconfig     |   1 +
>  drivers/media/i2c/video-i2c.c | 110 +++++++++++++++++++++++++++++++++-
>  2 files changed, 110 insertions(+), 1 deletion(-)



> 
> diff --git a/drivers/media/i2c/Kconfig b/drivers/media/i2c/Kconfig
> index 704af210e270..4bfb2c66d192 100644
> --- a/drivers/media/i2c/Kconfig
> +++ b/drivers/media/i2c/Kconfig
> @@ -1085,6 +1085,7 @@ config VIDEO_I2C
>  	  Enable the I2C transport video support which supports the
>  	  following:
>  	   * Panasonic AMG88xx Grid-Eye Sensors
> +	   * Melexis MLX90640 Thermal Cameras
>  
>  	  To compile this driver as a module, choose M here: the
>  	  module will be called video-i2c
> diff --git a/drivers/media/i2c/video-i2c.c b/drivers/media/i2c/video-i2c.c
> index 6d3b6df0b634..38ade8cb7656 100644
> --- a/drivers/media/i2c/video-i2c.c
> +++ b/drivers/media/i2c/video-i2c.c
> @@ -6,6 +6,7 @@
>   *
>   * Supported:
>   * - Panasonic AMG88xx Grid-Eye Sensors
> + * - Melexis MLX90640 Thermal Cameras
>   */
>  
>  #include <linux/delay.h>
> @@ -18,6 +19,7 @@
>  #include <linux/mutex.h>
>  #include <linux/of_device.h>
>  #include <linux/pm_runtime.h>
> +#include <linux/nvmem-provider.h>
>  #include <linux/regmap.h>
>  #include <linux/sched.h>
>  #include <linux/slab.h>
> @@ -66,12 +68,26 @@ static const struct v4l2_frmsize_discrete amg88xx_size = {
>  	.height = 8,
>  };
>  
> +static const struct v4l2_fmtdesc mlx90640_format = {
> +	.pixelformat = V4L2_PIX_FMT_Y16_BE,
> +};
> +
> +static const struct v4l2_frmsize_discrete mlx90640_size = {
> +	.width = 32,
> +	.height = 26, /* 24 lines of pixel data + 2 lines of processing data */
> +};
> +
>  static const struct regmap_config amg88xx_regmap_config = {
>  	.reg_bits = 8,
>  	.val_bits = 8,
>  	.max_register = 0xff
>  };
>  
> +static const struct regmap_config mlx90640_regmap_config = {
> +	.reg_bits = 16,
> +	.val_bits = 16,
> +};
> +
>  struct video_i2c_chip {
>  	/* video dimensions */
>  	const struct v4l2_fmtdesc *format;
> @@ -88,6 +104,7 @@ struct video_i2c_chip {
>  	unsigned int bpp;
>  
>  	const struct regmap_config *regmap_config;
> +	struct nvmem_config *nvmem_config;
>  
>  	/* setup function */
>  	int (*setup)(struct video_i2c_data *data);
> @@ -102,6 +119,22 @@ struct video_i2c_chip {
>  	int (*hwmon_init)(struct video_i2c_data *data);
>  };
>  
> +static int mlx90640_nvram_read(void *priv, unsigned int offset, void *val,
> +			     size_t bytes)
> +{
> +	struct video_i2c_data *data = priv;
> +
> +	return regmap_bulk_read(data->regmap, 0x2400 + offset, val, bytes);
> +}
> +
> +static struct nvmem_config mlx90640_nvram_config = {
> +	.name = "mlx90640_nvram",
> +	.word_size = 2,
> +	.stride = 1,
> +	.size = 1664,
> +	.reg_read = mlx90640_nvram_read,
> +};
> +
>  /* Power control register */
>  #define AMG88XX_REG_PCTL	0x00
>  #define AMG88XX_PCTL_NORMAL		0x00
> @@ -122,12 +155,23 @@ struct video_i2c_chip {
>  /* Temperature register */
>  #define AMG88XX_REG_T01L	0x80
>  
> +/* Control register */
> +#define MLX90640_REG_CTL1		0x800d
> +#define MLX90640_REG_CTL1_MASK		0x0380
> +#define MLX90640_REG_CTL1_MASK_SHIFT	7
> +
>  static int amg88xx_xfer(struct video_i2c_data *data, char *buf)
>  {
>  	return regmap_bulk_read(data->regmap, AMG88XX_REG_T01L, buf,
>  				data->chip->buffer_size);
>  }
>  
> +static int mlx90640_xfer(struct video_i2c_data *data, char *buf)
> +{
> +	return regmap_bulk_read(data->regmap, 0x400, buf,
> +				data->chip->buffer_size);
> +}
> +
>  static int amg88xx_setup(struct video_i2c_data *data)
>  {
>  	unsigned int mask = AMG88XX_FPSC_1FPS;
> @@ -141,6 +185,27 @@ static int amg88xx_setup(struct video_i2c_data *data)
>  	return regmap_update_bits(data->regmap, AMG88XX_REG_FPSC, mask, val);
>  }
>  
> +static int mlx90640_setup(struct video_i2c_data *data)
> +{
> +	unsigned int n, idx;
> +
> +	for (n = 0; n < data->chip->num_frame_intervals - 1; n++) {
> +		if (data->frame_interval.numerator
> +				!= data->chip->frame_intervals[n].numerator)
> +			continue;
> +
> +		if (data->frame_interval.denominator
> +				== data->chip->frame_intervals[n].denominator)
> +			break;
> +	}
> +
> +	idx = data->chip->num_frame_intervals - n - 1;
> +
> +	return regmap_update_bits(data->regmap, MLX90640_REG_CTL1,
> +				  MLX90640_REG_CTL1_MASK,
> +				  idx << MLX90640_REG_CTL1_MASK_SHIFT);
> +}
> +
>  static int amg88xx_set_power_on(struct video_i2c_data *data)
>  {
>  	int ret;
> @@ -274,13 +339,27 @@ static int amg88xx_hwmon_init(struct video_i2c_data *data)
>  #define	amg88xx_hwmon_init	NULL
>  #endif
>  
> -#define AMG88XX		0
> +enum {
> +	AMG88XX,
> +	MLX90640,
> +};
>  
>  static const struct v4l2_fract amg88xx_frame_intervals[] = {
>  	{ 1, 10 },
>  	{ 1, 1 },
>  };
>  
> +static const struct v4l2_fract mlx90640_frame_intervals[] = {
> +	{ 1, 64 },
> +	{ 1, 32 },
> +	{ 1, 16 },
> +	{ 1, 8 },
> +	{ 1, 4 },
> +	{ 1, 2 },
> +	{ 1, 1 },
> +	{ 2, 1 },
> +};
> +
>  static const struct video_i2c_chip video_i2c_chip[] = {
>  	[AMG88XX] = {
>  		.size		= &amg88xx_size,
> @@ -295,6 +374,18 @@ static const struct video_i2c_chip video_i2c_chip[] = {
>  		.set_power	= amg88xx_set_power,
>  		.hwmon_init	= amg88xx_hwmon_init,
>  	},
> +	[MLX90640] = {
> +		.size		= &mlx90640_size,
> +		.format		= &mlx90640_format,
> +		.frame_intervals	= mlx90640_frame_intervals,
> +		.num_frame_intervals	= ARRAY_SIZE(mlx90640_frame_intervals),
> +		.buffer_size	= 1664,
> +		.bpp		= 16,
> +		.regmap_config	= &mlx90640_regmap_config,
> +		.nvmem_config	= &mlx90640_nvram_config,
> +		.setup		= mlx90640_setup,
> +		.xfer		= mlx90640_xfer,
> +	},
>  };
>  
>  static const struct v4l2_file_operations video_i2c_fops = {
> @@ -756,6 +847,21 @@ static int video_i2c_probe(struct i2c_client *client,
>  		}
>  	}
>  
> +	if (data->chip->nvmem_config) {
> +		struct nvmem_config *config = data->chip->nvmem_config;
> +		struct nvmem_device *device;
> +
> +		config->priv = data;
> +		config->dev = &client->dev;
> +
> +		device = devm_nvmem_register(&client->dev, config);
> +
> +		if (IS_ERR(device)) {
> +			dev_warn(&client->dev,
> +				 "failed to register nvmem device\n");
> +		}
> +	}
> +
>  	ret = video_register_device(&data->vdev, VFL_TYPE_GRABBER, -1);
>  	if (ret < 0)
>  		goto error_pm_disable;
> @@ -834,12 +940,14 @@ static const struct dev_pm_ops video_i2c_pm_ops = {
>  
>  static const struct i2c_device_id video_i2c_id_table[] = {
>  	{ "amg88xx", AMG88XX },
> +	{ "mlx90640", MLX90640 },
>  	{}
>  };
>  MODULE_DEVICE_TABLE(i2c, video_i2c_id_table);
>  
>  static const struct of_device_id video_i2c_of_match[] = {
>  	{ .compatible = "panasonic,amg88xx", .data = &video_i2c_chip[AMG88XX] },
> +	{ .compatible = "melexis,mlx90640", .data = &video_i2c_chip[MLX90640] },

Missing documentation for melexis,mlx90640 in bindings:

WARNING: DT compatible string "melexis,mlx90640" appears un-documented -- check ./Documentation/devicetree/bindings/

Regards,

	Hans

>  	{}
>  };
>  MODULE_DEVICE_TABLE(of, video_i2c_of_match);
>