[v5 03/13] drm: Parse Colorimetry data block from EDID

[Sharma, Shashank]

> -----Original Message-----
> From: Shankar, Uma
> Sent: Monday, March 11, 2019 9:28 AM
> To: intel-gfx at lists.freedesktop.org; dri-devel at lists.freedesktop.org
> Cc: Lankhorst, Maarten <maarten.lankhorst at intel.com>; Syrjala, Ville
> <ville.syrjala at intel.com>; Sharma, Shashank <shashank.sharma at intel.com>;
> emil.l.velikov at gmail.com; brian.starkey at arm.com; Liviu.Dudau at arm.com; Shankar,
> Uma <uma.shankar at intel.com>
> Subject: [v5 03/13] drm: Parse Colorimetry data block from EDID
> 
> CEA 861.3 spec adds colorimetry data block for HDMI.
> Parsing the block to get the colorimetry data from panel.
> 
> v2: Rebase
> 
> v3: No Change
> 
> v4: Addressed Shashank's review comments. Updated colorimetry field to 16 bit as
> DCI-P3 got added in CEA 861-G spec, as pointed out by Shashank.
> 
> Signed-off-by: Uma Shankar <uma.shankar at intel.com>
> ---
>  drivers/gpu/drm/drm_edid.c  | 26 ++++++++++++++++++++++++++
> include/drm/drm_connector.h |  3 +++
>  2 files changed, 29 insertions(+)
> 
> diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c index
> c5a81b8..0470845 100644
> --- a/drivers/gpu/drm/drm_edid.c
> +++ b/drivers/gpu/drm/drm_edid.c
> @@ -2834,6 +2834,7 @@ static int drm_cvt_modes(struct drm_connector
> *connector,
>  #define VIDEO_BLOCK     0x02
>  #define VENDOR_BLOCK    0x03
>  #define SPEAKER_BLOCK	0x04
> +#define COLORIMETRY_DATA_BLOCK		0x5
>  #define HDR_STATIC_METADATA_BLOCK	0x6
>  #define USE_EXTENDED_TAG 0x07
>  #define EXT_VIDEO_CAPABILITY_BLOCK 0x00 @@ -3823,6 +3824,29 @@ static
> void fixup_detailed_cea_mode_clock(struct drm_display_mode *mode)
>  	mode->clock = clock;
>  }
> 
> +static bool cea_db_is_hdmi_colorimetry_data_block(const u8 *db) {
Same comment for the opening brace above ? 
> +	if (cea_db_tag(db) != USE_EXTENDED_TAG)
> +		return false;
> +
> +	if (db[1] != COLORIMETRY_DATA_BLOCK)
Space before '!' ? 
> +		return false;
> +
> +	return true;
> +}
> +
> +static void
> +drm_parse_colorimetry_data_block(struct drm_connector *connector, const
> +u8 *db) {
> +	struct drm_hdmi_info *info = &connector->display_info.hdmi;
> +	uint16_t len;
> +
> +	len = cea_db_payload_len_ext(db);
> +	/* As per CEA 861-G spec */
> +	info->colorimetry = ((db[3] & (0x1 << 7)) << 1) | db[2]; }
This means we are setting the 15th bit for DCI-P3 then there is a gap of 7 bits, and then there are other bits. Do we want to make DCI-P3 as bit 8 ? Anyways this can be differed for a discussion later. 
> +
> +
>  static bool cea_db_is_hdmi_hdr_metadata_block(const u8 *db)  {
>  	if (cea_db_tag(db) != USE_EXTENDED_TAG) @@ -4495,6 +4519,8 @@ static
> void drm_parse_cea_ext(struct drm_connector *connector,
>  			drm_parse_vcdb(connector, db);
>  		if (cea_db_is_hdmi_hdr_metadata_block(db))
>  			drm_parse_hdr_metadata_block(connector, db);
> +		if (cea_db_is_hdmi_colorimetry_data_block(db))
> +			drm_parse_colorimetry_data_block(connector, db);
>  	}
>  }
> 
> diff --git a/include/drm/drm_connector.h b/include/drm/drm_connector.h index
> 29388bd..94f926e 100644
> --- a/include/drm/drm_connector.h
> +++ b/include/drm/drm_connector.h
> @@ -206,6 +206,9 @@ struct drm_hdmi_info {
> 
>  	/** @y420_dc_modes: bitmap of deep color support index */
>  	u8 y420_dc_modes;
> +
> +	/* @colorimetry: bitmap of supported colorimetry modes */
> +	u16 colorimetry;
- Shashank
>  };
> 
>  /**
> --
> 1.9.1