Re: [PATCH v2 1/8] video/hdmi: Add common TMDS character rate constants

[Javier Martinez Canillas]

Javier Martinez Canillas <javierm@xxxxxxxxxx> writes:

[adding the dri-devel ML since patman didn't include it for this patch]

> Several DRM drivers already define their own constants for minimum and
> maximum TMDS character rates.
>
> By defining common rate constants in a shared header, drivers can just use
> them instead of having driver local define macros or use magic numbers.
>
> The values defined in the <linux/hdmi.h> header correspond to maximum TMDS
> character rates defined by each HDMI specification version:
>
>   - HDMI_TMDS_CHAR_RATE_MIN_HZ:     25 MHz (minimum for all versions)
>   - HDMI_1_0_TMDS_CHAR_RATE_MAX_HZ: 165 MHz (HDMI 1.0 maximum)
>   - HDMI_1_3_TMDS_CHAR_RATE_MAX_HZ: 340 MHz (HDMI 1.3 maximum)
>   - HDMI_2_0_TMDS_CHAR_RATE_MAX_HZ: 600 MHz (HDMI 2.0 maximum)
>
> Suggested-by: Maxime Ripard <mripard@xxxxxxxxxx>
> Signed-off-by: Javier Martinez Canillas <javierm@xxxxxxxxxx>
> Reviewed-by: Heiko Stuebner <heiko@xxxxxxxxx>
> ---
>
> Changes in v2:
> - Change naming convention to HDMI_$SPEC_TMDS_CHAR_RATE_MAX_HZ (Maxime).
> - Define the constants in <linux/hdmi.h> (Dmitry).
>
>  include/linux/hdmi.h | 6 ++++++
>  1 file changed, 6 insertions(+)
>
> diff --git a/include/linux/hdmi.h b/include/linux/hdmi.h
> index 96bda41d9148..8dab78e1f61b 100644
> --- a/include/linux/hdmi.h
> +++ b/include/linux/hdmi.h
> @@ -50,6 +50,12 @@ enum hdmi_infoframe_type {
>  	HDMI_INFOFRAME_TYPE_DRM = 0x87,
>  };
>  
> +/* HDMI spec maximum TMDS character rates, in Hz */
> +#define HDMI_TMDS_CHAR_RATE_MIN_HZ         25000000
> +#define HDMI_1_0_TMDS_CHAR_RATE_MAX_HZ    165000000
> +#define HDMI_1_3_TMDS_CHAR_RATE_MAX_HZ    340000000
> +#define HDMI_2_0_TMDS_CHAR_RATE_MAX_HZ    600000000
> +
>  #define HDMI_IEEE_OUI 0x000c03
>  #define HDMI_FORUM_IEEE_OUI 0xc45dd8
>  #define HDMI_INFOFRAME_HEADER_SIZE  4
> -- 
> 2.54.0
>

-- 
Best regards,

Javier Martinez Canillas
Core Platforms
Red Hat