Re: [PATCH v2 5/6] media: i2c: imx290: Add configurable link frequency and pixel rate

[Sakari Ailus]

Hi Manivannan,

On Thu, Dec 19, 2019 at 11:52:21PM +0530, Manivannan Sadhasivam wrote:
> IMX290 operates with multiple link frequency and pixel rate combinations.
> The initial driver used a single setting for both but since we now have
> the lane count support in place, let's add configurable link frequency
> and pixel rate.
> 
> Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx>
> ---
>  drivers/media/i2c/imx290.c | 155 +++++++++++++++++++++----------------
>  1 file changed, 89 insertions(+), 66 deletions(-)
> 
> diff --git a/drivers/media/i2c/imx290.c b/drivers/media/i2c/imx290.c
> index a1974340e6fa..52f1e470b507 100644
> --- a/drivers/media/i2c/imx290.c
> +++ b/drivers/media/i2c/imx290.c
> @@ -45,8 +45,6 @@
>  #define IMX290_HMAX_2_720 0x19C8
>  #define IMX290_HMAX_4_720 0x0CE4
>  
> -#define IMX290_DEFAULT_LINK_FREQ 445500000
> -
>  static const char * const imx290_supply_name[] = {
>  	"vdda",
>  	"vddd",
> @@ -63,8 +61,6 @@ struct imx290_regval {
>  struct imx290_mode {
>  	u32 width;
>  	u32 height;
> -	u32 pixel_rate;
> -	u32 link_freq_index;
>  
>  	const struct imx290_regval *data;
>  	u32 data_size;
> @@ -281,7 +277,10 @@ static const struct imx290_regval imx290_12bit_settings[] = {
>  
>  /* supported link frequencies */
>  static const s64 imx290_link_freq[] = {
> -	IMX290_DEFAULT_LINK_FREQ,
> +	891000000, /* 1920x1080 -  2 lane */
> +	445500000, /* 1920x1080 -  4 lane */
> +	594000000, /* 1280x720  -  2 lane */
> +	297000000, /* 1280x720  -  4 lane */

Please use different arrays for different lane configurations. That makes
this a lot cleaner.

This patch should precede the one adding support for 12 bpp.

>  };
>  
>  /* Mode configs */
> @@ -291,16 +290,12 @@ static const struct imx290_mode imx290_modes[] = {
>  		.height = 1080,
>  		.data = imx290_1080p_settings,
>  		.data_size = ARRAY_SIZE(imx290_1080p_settings),
> -		.pixel_rate = 178200000,
> -		.link_freq_index = 0,
>  	},
>  	{
>  		.width = 1280,
>  		.height = 720,
>  		.data = imx290_720p_settings,
>  		.data_size = ARRAY_SIZE(imx290_720p_settings),
> -		.pixel_rate = 178200000,
> -		.link_freq_index = 0,
>  	},
>  };
>  
> @@ -509,6 +504,73 @@ static int imx290_get_fmt(struct v4l2_subdev *sd,
>  	return 0;
>  }
>  
> +static s64 imx290_get_link_freq_index(struct imx290 *imx290)
> +{
> +	const struct imx290_mode *cur_mode = imx290->current_mode;
> +	u8 index;
> +
> +	if (cur_mode->width == 1920)
> +		index = imx290->nlanes / 4;
> +	else
> +		index = (imx290->nlanes / 4) + 2;
> +
> +	return index;
> +}
> +
> +static s64 imx290_get_link_freq(struct imx290 *imx290)
> +{
> +	u8 index = imx290_get_link_freq_index(imx290);
> +
> +	return imx290_link_freq[index];
> +}
> +
> +static u64 imx290_calc_pixel_rate(struct imx290 *imx290)
> +{
> +	s64 link_freq = imx290_get_link_freq(imx290);
> +	u8 nlanes = imx290->nlanes;
> +
> +	/* pixel rate = link_freq * 2 * nr_of_lanes / bits_per_sample */
> +	return (link_freq * 2 * nlanes / imx290->bpp);
> +}
> +
> +static int imx290_write_current_format(struct imx290 *imx290,
> +				       struct v4l2_mbus_framefmt *format)
> +{
> +	int ret;
> +
> +	switch (format->code) {
> +	case MEDIA_BUS_FMT_SRGGB10_1X10:
> +		ret = imx290_set_register_array(imx290, imx290_10bit_settings,
> +						ARRAY_SIZE(
> +							imx290_10bit_settings));
> +		if (ret < 0) {
> +			dev_err(imx290->dev, "Could not set format registers\n");
> +			return ret;
> +		}
> +
> +		imx290->bpp = 10;
> +
> +		break;
> +	case MEDIA_BUS_FMT_SRGGB12_1X12:
> +		ret = imx290_set_register_array(imx290, imx290_12bit_settings,
> +						ARRAY_SIZE(
> +							imx290_12bit_settings));
> +		if (ret < 0) {
> +			dev_err(imx290->dev, "Could not set format registers\n");
> +			return ret;
> +		}
> +
> +		imx290->bpp = 12;
> +
> +		break;
> +	default:
> +		dev_err(imx290->dev, "Unknown pixel format\n");
> +		return -EINVAL;
> +	}
> +
> +	return 0;
> +}
> +
>  static int imx290_set_fmt(struct v4l2_subdev *sd,
>  			  struct v4l2_subdev_pad_config *cfg,
>  		      struct v4l2_subdev_format *fmt)
> @@ -517,6 +579,7 @@ static int imx290_set_fmt(struct v4l2_subdev *sd,
>  	const struct imx290_mode *mode;
>  	struct v4l2_mbus_framefmt *format;
>  	unsigned int i;
> +	int ret = 0;
>  
>  	mutex_lock(&imx290->lock);
>  
> @@ -542,17 +605,27 @@ static int imx290_set_fmt(struct v4l2_subdev *sd,
>  		format = v4l2_subdev_get_try_format(sd, cfg, fmt->pad);
>  	} else {
>  		format = &imx290->current_format;
> -		__v4l2_ctrl_s_ctrl(imx290->link_freq, mode->link_freq_index);
> -		__v4l2_ctrl_s_ctrl_int64(imx290->pixel_rate, mode->pixel_rate);
> -
>  		imx290->current_mode = mode;
> +
> +		/* Set current frame format */
> +		ret = imx290_write_current_format(imx290, &fmt->format);
> +		if (ret < 0) {
> +			dev_err(imx290->dev, "Could not set frame format\n");
> +			goto err_out;
> +		}
> +
> +		__v4l2_ctrl_s_ctrl(imx290->link_freq,
> +				   imx290_get_link_freq_index(imx290));
> +		__v4l2_ctrl_s_ctrl_int64(imx290->pixel_rate,
> +					 imx290_calc_pixel_rate(imx290));
>  	}
>  
>  	*format = fmt->format;
>  
> +err_out:
>  	mutex_unlock(&imx290->lock);
>  
> -	return 0;
> +	return ret;
>  }
>  
>  static int imx290_entity_init_cfg(struct v4l2_subdev *subdev,
> @@ -569,44 +642,6 @@ static int imx290_entity_init_cfg(struct v4l2_subdev *subdev,
>  	return 0;
>  }
>  
> -static int imx290_write_current_format(struct imx290 *imx290,
> -				       struct v4l2_mbus_framefmt *format)
> -{
> -	int ret;
> -
> -	switch (format->code) {
> -	case MEDIA_BUS_FMT_SRGGB10_1X10:
> -		ret = imx290_set_register_array(imx290, imx290_10bit_settings,
> -						ARRAY_SIZE(
> -							imx290_10bit_settings));
> -		if (ret < 0) {
> -			dev_err(imx290->dev, "Could not set format registers\n");
> -			return ret;
> -		}
> -
> -		imx290->bpp = 10;
> -
> -		break;
> -	case MEDIA_BUS_FMT_SRGGB12_1X12:
> -		ret = imx290_set_register_array(imx290, imx290_12bit_settings,
> -						ARRAY_SIZE(
> -							imx290_12bit_settings));
> -		if (ret < 0) {
> -			dev_err(imx290->dev, "Could not set format registers\n");
> -			return ret;
> -		}
> -
> -		imx290->bpp = 12;
> -
> -		break;
> -	default:
> -		dev_err(imx290->dev, "Unknown pixel format\n");
> -		return -EINVAL;
> -	}
> -
> -	return 0;
> -}
> -
>  static int imx290_set_hmax(struct imx290 *imx290, u32 val)
>  {
>  	int ret;
> @@ -640,13 +675,6 @@ static int imx290_start_streaming(struct imx290 *imx290)
>  		return ret;
>  	}
>  
> -	/* Set current frame format */
> -	ret = imx290_write_current_format(imx290, &imx290->current_format);
> -	if (ret < 0) {
> -		dev_err(imx290->dev, "Could not set frame format\n");
> -		return ret;
> -	}
> -
>  	/* Apply default values of current mode */
>  	ret = imx290_set_register_array(imx290, imx290->current_mode->data,
>  					imx290->current_mode->data_size);
> @@ -904,12 +932,6 @@ static int imx290_probe(struct i2c_client *client)
>  		goto free_err;
>  	}
>  
> -	if (imx290->ep.link_frequencies[0] != IMX290_DEFAULT_LINK_FREQ) {
> -		dev_err(dev, "Unsupported link frequency\n");
> -		ret = -EINVAL;
> -		goto free_err;
> -	}
> -
>  	/* Only CSI2 is supported for now */
>  	if (imx290->ep.bus_type != V4L2_MBUS_CSI2_DPHY) {
>  		dev_err(dev, "Unsupported bus type, should be CSI2\n");
> @@ -976,14 +998,15 @@ static int imx290_probe(struct i2c_client *client)
>  				       &imx290_ctrl_ops,
>  				       V4L2_CID_LINK_FREQ,
>  				       ARRAY_SIZE(imx290_link_freq) - 1,
> -				       0, imx290_link_freq);
> +				       (imx290->nlanes / 4),
> +				       imx290_link_freq);
>  	if (imx290->link_freq)
>  		imx290->link_freq->flags |= V4L2_CTRL_FLAG_READ_ONLY;
>  
>  	imx290->pixel_rate = v4l2_ctrl_new_std(&imx290->ctrls, &imx290_ctrl_ops,
>  					       V4L2_CID_PIXEL_RATE, 1,
>  					       INT_MAX, 1,
> -					       imx290_modes[0].pixel_rate);
> +					       imx290_calc_pixel_rate(imx290));
>  
>  	v4l2_ctrl_new_std_menu_items(&imx290->ctrls, &imx290_ctrl_ops,
>  				     V4L2_CID_TEST_PATTERN,

-- 
Regards,

Sakari Ailus