video/hdmi: Add common TMDS character rate constants

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@kernel.org>
Reviewed-by: Heiko Stuebner <heiko@sntech.de>
Reviewed-by: Neil Armstrong <neil.armstrong@linaro.org>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
Reviewed-by: Maxime Ripard <mripard@kernel.org>
Link: https://patch.msgid.link/20260520144424.1633354-2-javierm@redhat.com
Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
This commit is contained in:
Javier Martinez Canillas 2026-05-20 16:43:37 +02:00
parent 9392e7340b
commit 988369959e
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@ -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