Hi Uma,
On Wed, Mar 20, 2019 at 04:18:16PM +0530, Uma Shankar wrote:
> CEA 861.3 spec adds colorimetry data block for HDMI.
> Parsing the block to get the colorimetry data from
> panel.
>
While code which parses these parts (patches 2 and 3) out of EDID
could be useful - it doesn't seem to actually be used anywhere in the
kernel (sorry if I missed it), and I'm not sure it will/can be unless
we expose more properties.
The discussion last time leant towards a more useful/generic userspace
library for EDID parsing, so perhaps patches 2 and 3 should be
dropped.
Did you have an intended use for them in the kernel?
Thanks,
-Brian
> 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.
>
> v5: Fixed checkpatch warnings with --strict option.
>
> Signed-off-by: Uma Shankar <uma.shankar@xxxxxxxxx>
> Reviewed-by: Shashank Sharma <shashank.sharma@xxxxxxxxx>
> ---
> drivers/gpu/drm/drm_edid.c | 25 +++++++++++++++++++++++++
> include/drm/drm_connector.h | 3 +++
> 2 files changed, 28 insertions(+)
>
> diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c
> index fd8a621a..676569b 100644
> --- a/drivers/gpu/drm/drm_edid.c
> +++ b/drivers/gpu/drm/drm_edid.c
> @@ -2840,6 +2840,7 @@ 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
> @@ -3829,6 +3830,28 @@ 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)
> +{
> + if (cea_db_tag(db) != USE_EXTENDED_TAG)
> + return false;
> +
> + if (db[1] != COLORIMETRY_DATA_BLOCK)
> + 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;
> + u16 len;
> +
> + len = cea_db_payload_len_ext(db);
> + /* As per CEA 861-G spec */
> + info->colorimetry = ((db[3] & (0x1 << 7)) << 1) | db[2];
> +}
> +
> static bool cea_db_is_hdmi_hdr_metadata_block(const u8 *db)
> {
> if (cea_db_tag(db) != USE_EXTENDED_TAG)
> @@ -4498,6 +4521,8 @@ 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;
> };
>
> /**
> --
> 1.9.1
>
_______________________________________________
Intel-gfx mailing list
Intel-gfx@xxxxxxxxxxxxxxxxxxxxx
https://lists.freedesktop.org/mailman/listinfo/intel-gfx
