Add a helper for skipping the HDMI VSDB audio latency fields. There's a functional change for HDMI VSDB blocks that do not respect the spec: "I_Latency_Fields_Present shall be zero if Latency_Fields_Present is zero". We assume this to hold when skipping the latency fields, and ignore non-zero I_Latency_Fields_Present if Latency_Fields_Present is zero.
Cc: Ville Syrjälä <[email protected]> Signed-off-by: Jani Nikula <[email protected]> --- drivers/gpu/drm/drm_edid.c | 18 +++++++++++------- 1 file changed, 11 insertions(+), 7 deletions(-) diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c index 847076b29594..93067b8dd9f6 100644 --- a/drivers/gpu/drm/drm_edid.c +++ b/drivers/gpu/drm/drm_edid.c @@ -4695,6 +4695,16 @@ static bool hdmi_vsdb_i_latency_present(const u8 *db) return hdmi_vsdb_latency_present(db) && db[8] & BIT(6); } +static int hdmi_vsdb_latency_length(const u8 *db) +{ + if (hdmi_vsdb_i_latency_present(db)) + return 4; + else if (hdmi_vsdb_latency_present(db)) + return 2; + else + return 0; +} + /* * do_hdmi_vsdb_modes - Parse the HDMI Vendor Specific data block * @connector: connector corresponding to the HDMI sink @@ -4720,13 +4730,7 @@ do_hdmi_vsdb_modes(struct drm_connector *connector, const u8 *db, u8 len) if (!(db[8] & (1 << 5))) goto out; - /* Latency_Fields_Present */ - if (db[8] & (1 << 7)) - offset += 2; - - /* I_Latency_Fields_Present */ - if (db[8] & (1 << 6)) - offset += 2; + offset += hdmi_vsdb_latency_length(db); /* the declared length is not long enough for the 2 first bytes * of additional video format capabilities */ -- 2.34.1
