[PATCH 1/2] drm/edid: add #defines and helpers for ELD

[Rodrigo Vivi]

On Tue, Oct 28, 2014 at 7:20 AM, Jani Nikula <jani.nikula at intel.com> wrote:
> In the interest of reducing magic numbers and having to cross check with
> the specs all the time.
>
> Signed-off-by: Jani Nikula <jani.nikula at intel.com>
> ---
>  include/drm/drm_edid.h | 102 +++++++++++++++++++++++++++++++++++++++++++++++++
>  1 file changed, 102 insertions(+)
>
> diff --git a/include/drm/drm_edid.h b/include/drm/drm_edid.h
> index b96031d947a0..c2f1bfa22010 100644
> --- a/include/drm/drm_edid.h
> +++ b/include/drm/drm_edid.h
> @@ -207,6 +207,61 @@ struct detailed_timing {
>  #define DRM_EDID_HDMI_DC_30               (1 << 4)
>  #define DRM_EDID_HDMI_DC_Y444             (1 << 3)
>
> +/* ELD Header Block */
> +#define DRM_ELD_HEADER_BLOCK_SIZE      4
> +
> +#define DRM_ELD_VER                    0
> +# define DRM_ELD_VER_SHIFT             3
> +# define DRM_ELD_VER_MASK              (0x1f << 3)
> +
> +#define DRM_ELD_BASELINE_ELD_LEN       2       /* in dwords! */
> +
> +/* ELD Baseline Block for ELD_Ver == 2 */
> +#define DRM_ELD_CEA_EDID_VER_MNL       4
Oh, this VER_MNL name confused me a lot during review.... confusing
with MNN_SHIFT.
But since I don't have a better suggestions nevermind ;)

> +# define DRM_ELD_CEA_EDID_VER_SHIFT    5
> +# define DRM_ELD_CEA_EDID_VER_MASK     (7 << 5)
> +# define DRM_ELD_CEA_EDID_VER_NONE     (0 << 5)
> +# define DRM_ELD_CEA_EDID_VER_CEA861   (1 << 5)
> +# define DRM_ELD_CEA_EDID_VER_CEA861A  (2 << 5)
> +# define DRM_ELD_CEA_EDID_VER_CEA861BCD        (3 << 5)
> +# define DRM_ELD_MNL_SHIFT             0
> +# define DRM_ELD_MNL_MASK              (0x1f << 0)
> +
> +#define DRM_ELD_SAD_COUNT_CONN_TYPE    5
> +# define DRM_ELD_SAD_COUNT_SHIFT       4
> +# define DRM_ELD_SAD_COUNT_MASK                (0xf << 4)
> +# define DRM_ELD_CONN_TYPE_SHIFT       2
> +# define DRM_ELD_CONN_TYPE_MASK                (3 << 2)
> +# define DRM_ELD_CONN_TYPE_HDMI                (0 << 2)
> +# define DRM_ELD_CONN_TYPE_DP          (1 << 2)
> +# define DRM_ELD_SUPPORTS_AI           (1 << 1)
> +# define DRM_ELD_SUPPORTS_HDCP         (1 << 0)
> +
> +#define DRM_ELD_AUD_SYNCH_DELAY                6       /* in units of 2 ms */
> +# define DRM_ELD_AUD_SYNCH_DELAY_MAX   0xfa    /* 500 ms */
> +
> +#define DRM_ELD_SPEAKER                        7
> +# define DRM_ELD_SPEAKER_RLRC          (1 << 6)
> +# define DRM_ELD_SPEAKER_FLRC          (1 << 5)
> +# define DRM_ELD_SPEAKER_RC            (1 << 4)
> +# define DRM_ELD_SPEAKER_RLR           (1 << 3)
> +# define DRM_ELD_SPEAKER_FC            (1 << 2)
> +# define DRM_ELD_SPEAKER_LFE           (1 << 1)
> +# define DRM_ELD_SPEAKER_FLR           (1 << 0)
> +
> +#define DRM_ELD_PORT_ID                        8       /* offsets 8..15 inclusive */
> +# define DRM_ELD_PORT_ID_LEN           8
> +
> +#define DRM_ELD_MANUFACTURER_NAME0     16
> +#define DRM_ELD_MANUFACTURER_NAME1     17
> +
> +#define DRM_ELD_PRODUCT_CODE0          18
> +#define DRM_ELD_PRODUCT_CODE1          19
> +
> +#define DRM_ELD_MONITOR_NAME_STRING    20      /* offsets 20..(20+mnl-1) inclusive */
> +
> +#define DRM_ELD_CEA_SAD(mnl, sad)      (20 + (mnl) + 3 * (sad))
> +
>  struct edid {
>         u8 header[8];
>         /* Vendor & product info */
> @@ -279,4 +334,51 @@ int
>  drm_hdmi_vendor_infoframe_from_display_mode(struct hdmi_vendor_infoframe *frame,
>                                             const struct drm_display_mode *mode);
>
> +/**
> + * drm_eld_mnl - Get ELD monitor name length in bytes.
> + * @eld: pointer to an eld memory structure with mnl set
> + */
> +static inline int drm_eld_mnl(const uint8_t *eld)
> +{
> +       return (eld[DRM_ELD_CEA_EDID_VER_MNL] & DRM_ELD_MNL_MASK) >> DRM_ELD_MNL_SHIFT;
> +}
> +
> +/**
> + * drm_eld_sad_count - Get ELD SAD count.
> + * @eld: pointer to an eld memory structure with sad_count set
> + */
> +static inline int drm_eld_sad_count(const uint8_t *eld)
> +{
> +       return (eld[DRM_ELD_SAD_COUNT_CONN_TYPE] & DRM_ELD_SAD_COUNT_MASK) >>
> +               DRM_ELD_SAD_COUNT_SHIFT;
> +}
> +
> +/**
> + * drm_eld_calc_baseline_block_size - Calculate baseline block size in bytes
> + * @eld: pointer to an eld memory structure with mnl and sad_count set
> + *
> + * This is a helper for determining the payload size of the baseline block, in
> + * bytes, for e.g. setting the Baseline_ELD_Len field in the ELD header block.
> + */
> +static inline int drm_eld_calc_baseline_block_size(const uint8_t *eld)
> +{
> +       return DRM_ELD_MONITOR_NAME_STRING - DRM_ELD_HEADER_BLOCK_SIZE +
> +               drm_eld_mnl(eld) + drm_eld_sad_count(eld) * 3;
> +}
> +
> +/**
> + * drm_eld_size - Get ELD size in bytes
> + * @eld: pointer to a complete eld memory structure
> + *
> + * The returned value does not include the vendor block. It's vendor specific,
> + * and comprises of the remaining bytes in the ELD memory buffer after
> + * drm_eld_size() bytes of header and baseline block.
> + *
> + * The returned value is guaranteed to be a multiple of 4.
> + */
> +static inline int drm_eld_size(const uint8_t *eld)
> +{
> +       return DRM_ELD_HEADER_BLOCK_SIZE + eld[DRM_ELD_BASELINE_ELD_LEN] * 4;
> +}
> +
>  #endif /* __DRM_EDID_H__ */
> --
> 2.1.1
>

Reviewed-by: Rodrigo Vivi <rodrigo.vivi at intel.com>

-- 
Rodrigo Vivi
Blog: http://blog.vivi.eng.br